diff options
Diffstat (limited to 'ubifs-utils/libubifs')
29 files changed, 25760 insertions, 0 deletions
diff --git a/ubifs-utils/libubifs/README b/ubifs-utils/libubifs/README new file mode 100644 index 0000000..dd9322a --- /dev/null +++ b/ubifs-utils/libubifs/README @@ -0,0 +1,30 @@ +UBIFS Library (Imported from linux kernel 6.13-rc7 aa22f4da2a46) + +* ubifs.h is a selection of definitions from fs/ubifs/ubifs.h from the linux kernel. +* key.h is copied from fs/ubifs/key.h from the linux kernel. +* ubifs-media.h is copied from fs/ubifs/ubifs-media.h from the linux kernel. +* find.c is copied from fs/ubifs/find.c from the linux kernel. +* scan.c is copied from fs/ubifs/scan.c from the linux kernel. +* gc.c is copied from fs/ubifs/gc.c from the linux kernel. +* log.c is copied from fs/ubifs/log.c from the linux kernel, and amended. +* tnc_commit.c is copied from fs/ubifs/tnc_commit.c from the linux kernel, and amended. +* master.c is copied from fs/ubifs/master.c from the linux kernel, and amended. +* recovery.c is copied from fs/ubifs/recovery.c from the linux kernel, and amended. +* lpt.c is a selection of functions copied from fs/ubifs/lpt.c from the linux kernel, and amended. +* auth.c is a selection of functions copied from fs/ubifs/auth.c from the linux kernel, and amended. +* budget.c is a selection of functions copied from fs/ubifs/budget.c from the linux kernel, and amended. +* commit.c is a selection of functions copied from fs/ubifs/commit.c from the linux kernel, and amended. +* debug.c is a selection of functions copied from fs/ubifs/debug.c from the linux kernel, and amended. +* debug.h is a selection of functions copied from fs/ubifs/debug.h from the linux kernel, and amended. +* io.c is a selection of functions copied from fs/ubifs/io.c from the linux kernel, and amended. +* lprops.c is a selection of functions copied from fs/ubifs/lprops.c from the linux kernel, and amended. +* lpt_commit.c is a selection of functions copied from fs/ubifs/lpt_commit.c from the linux kernel, and amended. +* misc.h is a selection of functions copied from fs/ubifs/misc.h from the linux kernel, and amended. +* orphan.c is a selection of functions copied from fs/ubifs/orphan.c from the linux kernel, and amended. +* replay.c is a selection of functions copied from fs/ubifs/replay.c from the linux kernel, and amended. +* sb.c is a selection of functions copied from fs/ubifs/sb.c from the linux kernel, and amended. +* super.c is a selection of functions copied from fs/ubifs/super.c from the linux kernel, and amended. +* tnc.c is a selection of functions copied from fs/ubifs/tnc.c from the linux kernel, and amended. +* tnc_misc.c is a selection of functions copied from fs/ubifs/tnc_misc.c from the linux kernel, and amended. +* journal.c is a selection of functions copied from fs/ubifs/journal.c from the linux kernel, and amended. +* dir.c is a selection of functions copied from fs/ubifs/dir.c from the linux kernel, and amended. diff --git a/ubifs-utils/libubifs/auth.c b/ubifs-utils/libubifs/auth.c new file mode 100644 index 0000000..fab1dba --- /dev/null +++ b/ubifs-utils/libubifs/auth.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This file is part of UBIFS. + * + * Copyright (C) 2018 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de> + */ + +/* + * This file implements various helper functions for UBIFS authentication support + */ + +#include "linux_err.h" +#include "ubifs.h" +#include "sign.h" +#include "defs.h" + +int ubifs_shash_init(const struct ubifs_info *c, + __unused struct shash_desc *desc) +{ + if (ubifs_authenticated(c)) + return hash_digest_init(); + else + return 0; +} + +int ubifs_shash_update(const struct ubifs_info *c, + __unused struct shash_desc *desc, + const void *buf, unsigned int len) +{ + int err = 0; + + if (ubifs_authenticated(c)) { + err = hash_digest_update(buf, len); + if (err < 0) + return err; + } + + return 0; +} + +int ubifs_shash_final(const struct ubifs_info *c, + __unused struct shash_desc *desc, u8 *out) +{ + return ubifs_authenticated(c) ? hash_digest_final(out) : 0; +} + +struct shash_desc *ubifs_hash_get_desc(const struct ubifs_info *c) +{ + int err; + + err = ubifs_shash_init(c, NULL); + if (err) + return ERR_PTR(err); + + return NULL; +} + +/** + * ubifs_node_calc_hash - calculate the hash of a UBIFS node + * @c: UBIFS file-system description object + * @node: the node to calculate a hash for + * @hash: the returned hash + * + * Returns 0 for success or a negative error code otherwise. + */ +int __ubifs_node_calc_hash(__unused const struct ubifs_info *c, + const void *node, u8 *hash) +{ + const struct ubifs_ch *ch = node; + + return hash_digest(node, le32_to_cpu(ch->len), hash); +} + +/** + * ubifs_master_node_calc_hash - calculate the hash of a UBIFS master node + * @node: the node to calculate a hash for + * @hash: the returned hash + */ +int ubifs_master_node_calc_hash(const struct ubifs_info *c, const void *node, + uint8_t *hash) +{ + if (!ubifs_authenticated(c)) + return 0; + + return hash_digest(node + sizeof(struct ubifs_ch), + UBIFS_MST_NODE_SZ - sizeof(struct ubifs_ch), hash); +} + +int ubifs_sign_superblock_node(struct ubifs_info *c, void *node) +{ + int err, len; + struct ubifs_sig_node *sig = node + UBIFS_SB_NODE_SZ; + + if (!ubifs_authenticated(c)) + return 0; + + err = hash_sign_node(c->auth_key_filename, c->auth_cert_filename, node, + &len, sig + 1); + if (err) + return err; + + sig->type = UBIFS_SIGNATURE_TYPE_PKCS7; + sig->len = cpu_to_le32(len); + sig->ch.node_type = UBIFS_SIG_NODE; + + return 0; +} + +/** + * ubifs_bad_hash - Report hash mismatches + * @c: UBIFS file-system description object + * @node: the node + * @hash: the expected hash + * @lnum: the LEB @node was read from + * @offs: offset in LEB @node was read from + * + * This function reports a hash mismatch when a node has a different hash than + * expected. + */ +void ubifs_bad_hash(const struct ubifs_info *c, const void *node, const u8 *hash, + int lnum, int offs) +{ + int len = min(c->hash_len, 20); + int cropped = len != c->hash_len; + const char *cont = cropped ? "..." : ""; + + u8 calc[UBIFS_HASH_ARR_SZ]; + + __ubifs_node_calc_hash(c, node, calc); + + ubifs_err(c, "hash mismatch on node at LEB %d:%d", lnum, offs); + ubifs_err(c, "hash expected: %*ph%s", len, hash, cont); + ubifs_err(c, "hash calculated: %*ph%s", len, calc, cont); +} + +/** + * ubifs_init_authentication - initialize UBIFS authentication support + * @c: UBIFS file-system description object + * + * This function returns 0 for success or a negative error code otherwise. + */ +int ubifs_init_authentication(struct ubifs_info *c) +{ + int err, hash_len, hash_algo; + + if (!c->auth_key_filename && !c->auth_cert_filename && !c->hash_algo_name) + return 0; + + if (!c->auth_key_filename) { + ubifs_err(c, "authentication key not given (--auth-key)"); + return -EINVAL; + } + + if (!c->hash_algo_name) { + ubifs_err(c, "Hash algorithm not given (--hash-algo)"); + return -EINVAL; + } + + err = init_authentication(c->hash_algo_name, &hash_len, &hash_algo); + if (err) { + ubifs_err(c, "Init authentication failed"); + return err; + } + + c->hash_len = hash_len; + c->hash_algo = hash_algo; + c->authenticated = 1; + + return 0; +} + +void __ubifs_exit_authentication(__unused struct ubifs_info *c) +{ + exit_authentication(); +} diff --git a/ubifs-utils/libubifs/budget.c b/ubifs-utils/libubifs/budget.c new file mode 100644 index 0000000..5550c9a --- /dev/null +++ b/ubifs-utils/libubifs/budget.c @@ -0,0 +1,595 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the budgeting sub-system which is responsible for UBIFS + * space management. + * + * Factors such as compression, wasted space at the ends of LEBs, space in other + * journal heads, the effect of updates on the index, and so on, make it + * impossible to accurately predict the amount of space needed. Consequently + * approximations are used. + */ + +#include "bitops.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "misc.h" + +/* + * When pessimistic budget calculations say that there is no enough space, + * UBIFS starts writing back dirty inodes and pages, doing garbage collection, + * or committing. The below constant defines maximum number of times UBIFS + * repeats the operations. + */ +#define MAX_MKSPC_RETRIES 3 + +/** + * run_gc - run garbage collector. + * @c: UBIFS file-system description object + * + * This function runs garbage collector to make some more free space. Returns + * zero if a free LEB has been produced, %-EAGAIN if commit is required, and a + * negative error code in case of failure. + */ +static int run_gc(struct ubifs_info *c) +{ + int lnum; + + /* Make some free space by garbage-collecting dirty space */ + down_read(&c->commit_sem); + lnum = ubifs_garbage_collect(c, 1); + up_read(&c->commit_sem); + if (lnum < 0) + return lnum; + + /* GC freed one LEB, return it to lprops */ + dbg_budg("GC freed LEB %d", lnum); + return ubifs_return_leb(c, lnum); +} + +/** + * make_free_space - make more free space on the file-system. + * @c: UBIFS file-system description object + * + * This function is called when an operation cannot be budgeted because there + * is supposedly no free space. But in most cases there is some free space: + * o budgeting is pessimistic, so it always budgets more than it is actually + * needed, so shrinking the liability is one way to make free space - the + * cached data will take less space then it was budgeted for; + * o GC may turn some dark space into free space (budgeting treats dark space + * as not available); + * o commit may free some LEB, i.e., turn freeable LEBs into free LEBs. + * + * So this function tries to do the above. Returns %-EAGAIN if some free space + * was presumably made and the caller has to re-try budgeting the operation. + * Returns %-ENOSPC if it couldn't do more free space, and other negative error + * codes on failures. + */ +static int make_free_space(struct ubifs_info *c) +{ + int err, retries = 0; + + do { + dbg_budg("Run GC"); + err = run_gc(c); + if (!err) + return -EAGAIN; + + if (err != -EAGAIN && err != -ENOSPC) + /* Some real error happened */ + return err; + + dbg_budg("Run commit (retries %d)", retries); + err = ubifs_run_commit(c); + if (err) + return err; + } while (retries++ < MAX_MKSPC_RETRIES); + + return -ENOSPC; +} + +/** + * ubifs_calc_min_idx_lebs - calculate amount of LEBs for the index. + * @c: UBIFS file-system description object + * + * This function calculates and returns the number of LEBs which should be kept + * for index usage. + */ +int ubifs_calc_min_idx_lebs(struct ubifs_info *c) +{ + int idx_lebs; + long long idx_size; + + idx_size = c->bi.old_idx_sz + c->bi.idx_growth + c->bi.uncommitted_idx; + /* And make sure we have thrice the index size of space reserved */ + idx_size += idx_size << 1; + /* + * We do not maintain 'old_idx_size' as 'old_idx_lebs'/'old_idx_bytes' + * pair, nor similarly the two variables for the new index size, so we + * have to do this costly 64-bit division on fast-path. + */ + idx_lebs = div_u64(idx_size + c->idx_leb_size - 1, c->idx_leb_size); + /* + * The index head is not available for the in-the-gaps method, so add an + * extra LEB to compensate. + */ + idx_lebs += 1; + if (idx_lebs < MIN_INDEX_LEBS) + idx_lebs = MIN_INDEX_LEBS; + return idx_lebs; +} + +/** + * ubifs_calc_available - calculate available FS space. + * @c: UBIFS file-system description object + * @min_idx_lebs: minimum number of LEBs reserved for the index + * + * This function calculates and returns amount of FS space available for use. + */ +long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs) +{ + int subtract_lebs; + long long available; + + available = c->main_bytes - c->lst.total_used; + + /* + * Now 'available' contains theoretically available flash space + * assuming there is no index, so we have to subtract the space which + * is reserved for the index. + */ + subtract_lebs = min_idx_lebs; + + /* Take into account that GC reserves one LEB for its own needs */ + subtract_lebs += 1; + + /* + * Since different write types go to different heads, we should + * reserve one leb for each head. + */ + subtract_lebs += c->jhead_cnt; + + /* We also reserve one LEB for deletions, which bypass budgeting */ + subtract_lebs += 1; + + available -= (long long)subtract_lebs * c->leb_size; + + /* Subtract the dead space which is not available for use */ + available -= c->lst.total_dead; + + /* + * Subtract dark space, which might or might not be usable - it depends + * on the data which we have on the media and which will be written. If + * this is a lot of uncompressed or not-compressible data, the dark + * space cannot be used. + */ + available -= c->lst.total_dark; + + /* + * However, there is more dark space. The index may be bigger than + * @min_idx_lebs. Those extra LEBs are assumed to be available, but + * their dark space is not included in total_dark, so it is subtracted + * here. + */ + if (c->lst.idx_lebs > min_idx_lebs) { + subtract_lebs = c->lst.idx_lebs - min_idx_lebs; + available -= subtract_lebs * c->dark_wm; + } + + /* The calculations are rough and may end up with a negative number */ + return available > 0 ? available : 0; +} + +/** + * can_use_rp - check whether the user is allowed to use reserved pool. + * @c: UBIFS file-system description object + * + * UBIFS has so-called "reserved pool" which is flash space reserved + * for the superuser and for uses whose UID/GID is recorded in UBIFS superblock. + * This function checks whether current user is allowed to use reserved pool. + * Returns %1 current user is allowed to use reserved pool and %0 otherwise. + */ +static int can_use_rp(__unused struct ubifs_info *c) +{ + /* Fsck can always use reserved pool. */ + return c->program_type == FSCK_PROGRAM_TYPE; +} + +/** + * do_budget_space - reserve flash space for index and data growth. + * @c: UBIFS file-system description object + * + * This function makes sure UBIFS has enough free LEBs for index growth and + * data. + * + * When budgeting index space, UBIFS reserves thrice as many LEBs as the index + * would take if it was consolidated and written to the flash. This guarantees + * that the "in-the-gaps" commit method always succeeds and UBIFS will always + * be able to commit dirty index. So this function basically adds amount of + * budgeted index space to the size of the current index, multiplies this by 3, + * and makes sure this does not exceed the amount of free LEBs. + * + * Notes about @c->bi.min_idx_lebs and @c->lst.idx_lebs variables: + * o @c->lst.idx_lebs is the number of LEBs the index currently uses. It might + * be large, because UBIFS does not do any index consolidation as long as + * there is free space. IOW, the index may take a lot of LEBs, but the LEBs + * will contain a lot of dirt. + * o @c->bi.min_idx_lebs is the number of LEBS the index presumably takes. IOW, + * the index may be consolidated to take up to @c->bi.min_idx_lebs LEBs. + * + * This function returns zero in case of success, and %-ENOSPC in case of + * failure. + */ +static int do_budget_space(struct ubifs_info *c) +{ + long long outstanding, available; + int lebs, rsvd_idx_lebs, min_idx_lebs; + + /* First budget index space */ + min_idx_lebs = ubifs_calc_min_idx_lebs(c); + + /* Now 'min_idx_lebs' contains number of LEBs to reserve */ + if (min_idx_lebs > c->lst.idx_lebs) + rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs; + else + rsvd_idx_lebs = 0; + + /* + * The number of LEBs that are available to be used by the index is: + * + * @c->lst.empty_lebs + @c->freeable_cnt + @c->idx_gc_cnt - + * @c->lst.taken_empty_lebs + * + * @c->lst.empty_lebs are available because they are empty. + * @c->freeable_cnt are available because they contain only free and + * dirty space, @c->idx_gc_cnt are available because they are index + * LEBs that have been garbage collected and are awaiting the commit + * before they can be used. And the in-the-gaps method will grab these + * if it needs them. @c->lst.taken_empty_lebs are empty LEBs that have + * already been allocated for some purpose. + * + * Note, @c->idx_gc_cnt is included to both @c->lst.empty_lebs (because + * these LEBs are empty) and to @c->lst.taken_empty_lebs (because they + * are taken until after the commit). + * + * Note, @c->lst.taken_empty_lebs may temporarily be higher by one + * because of the way we serialize LEB allocations and budgeting. See a + * comment in 'ubifs_find_free_space()'. + */ + lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt - + c->lst.taken_empty_lebs; + if (unlikely(rsvd_idx_lebs > lebs)) { + dbg_budg("out of indexing space: min_idx_lebs %d (old %d), rsvd_idx_lebs %d", + min_idx_lebs, c->bi.min_idx_lebs, rsvd_idx_lebs); + return -ENOSPC; + } + + available = ubifs_calc_available(c, min_idx_lebs); + outstanding = c->bi.data_growth + c->bi.dd_growth; + + if (unlikely(available < outstanding)) { + dbg_budg("out of data space: available %lld, outstanding %lld", + available, outstanding); + return -ENOSPC; + } + + if (available - outstanding <= c->rp_size && !can_use_rp(c)) + return -ENOSPC; + + c->bi.min_idx_lebs = min_idx_lebs; + return 0; +} + +/** + * calc_idx_growth - calculate approximate index growth from budgeting request. + * @c: UBIFS file-system description object + * @req: budgeting request + * + * For now we assume each new node adds one znode. But this is rather poor + * approximation, though. + */ +static int calc_idx_growth(const struct ubifs_info *c, + const struct ubifs_budget_req *req) +{ + int znodes; + + znodes = req->new_ino + (req->new_page << UBIFS_BLOCKS_PER_PAGE_SHIFT) + + req->new_dent; + return znodes * c->max_idx_node_sz; +} + +/** + * calc_data_growth - calculate approximate amount of new data from budgeting + * request. + * @c: UBIFS file-system description object + * @req: budgeting request + */ +static int calc_data_growth(const struct ubifs_info *c, + const struct ubifs_budget_req *req) +{ + int data_growth; + + data_growth = req->new_ino ? c->bi.inode_budget : 0; + if (req->new_page) + data_growth += c->bi.page_budget; + if (req->new_dent) + data_growth += c->bi.dent_budget; + data_growth += req->new_ino_d; + return data_growth; +} + +/** + * calc_dd_growth - calculate approximate amount of data which makes other data + * dirty from budgeting request. + * @c: UBIFS file-system description object + * @req: budgeting request + */ +static int calc_dd_growth(const struct ubifs_info *c, + const struct ubifs_budget_req *req) +{ + int dd_growth; + + dd_growth = req->dirtied_page ? c->bi.page_budget : 0; + + if (req->dirtied_ino) + dd_growth += c->bi.inode_budget * req->dirtied_ino; + if (req->mod_dent) + dd_growth += c->bi.dent_budget; + dd_growth += req->dirtied_ino_d; + return dd_growth; +} + +/** + * ubifs_budget_space - ensure there is enough space to complete an operation. + * @c: UBIFS file-system description object + * @req: budget request + * + * This function allocates budget for an operation. It uses pessimistic + * approximation of how much flash space the operation needs. The goal of this + * function is to make sure UBIFS always has flash space to flush all dirty + * pages, dirty inodes, and dirty znodes (liability). This function may force + * commit, garbage-collection or write-back. Returns zero in case of success, + * %-ENOSPC if there is no free space and other negative error codes in case of + * failures. + */ +int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req) +{ + int err, idx_growth, data_growth, dd_growth, retried = 0; + + ubifs_assert(c, req->new_page <= 1); + ubifs_assert(c, req->dirtied_page <= 1); + ubifs_assert(c, req->new_dent <= 1); + ubifs_assert(c, req->mod_dent <= 1); + ubifs_assert(c, req->new_ino <= 1); + ubifs_assert(c, req->new_ino_d <= UBIFS_MAX_INO_DATA); + ubifs_assert(c, req->dirtied_ino <= 4); + ubifs_assert(c, req->dirtied_ino_d <= UBIFS_MAX_INO_DATA * 4); + ubifs_assert(c, !(req->new_ino_d & 7)); + ubifs_assert(c, !(req->dirtied_ino_d & 7)); + + data_growth = calc_data_growth(c, req); + dd_growth = calc_dd_growth(c, req); + if (!data_growth && !dd_growth) + return 0; + idx_growth = calc_idx_growth(c, req); + +again: + spin_lock(&c->space_lock); + ubifs_assert(c, c->bi.idx_growth >= 0); + ubifs_assert(c, c->bi.data_growth >= 0); + ubifs_assert(c, c->bi.dd_growth >= 0); + + if (unlikely(c->bi.nospace) && (c->bi.nospace_rp || !can_use_rp(c))) { + dbg_budg("no space"); + spin_unlock(&c->space_lock); + return -ENOSPC; + } + + c->bi.idx_growth += idx_growth; + c->bi.data_growth += data_growth; + c->bi.dd_growth += dd_growth; + + err = do_budget_space(c); + if (likely(!err)) { + req->idx_growth = idx_growth; + req->data_growth = data_growth; + req->dd_growth = dd_growth; + spin_unlock(&c->space_lock); + return 0; + } + + /* Restore the old values */ + c->bi.idx_growth -= idx_growth; + c->bi.data_growth -= data_growth; + c->bi.dd_growth -= dd_growth; + spin_unlock(&c->space_lock); + + if (req->fast) { + dbg_budg("no space for fast budgeting"); + return err; + } + + err = make_free_space(c); + cond_resched(); + if (err == -EAGAIN) { + dbg_budg("try again"); + goto again; + } else if (err == -ENOSPC) { + if (!retried) { + retried = 1; + dbg_budg("-ENOSPC, but anyway try once again"); + goto again; + } + dbg_budg("FS is full, -ENOSPC"); + c->bi.nospace = 1; + if (can_use_rp(c) || c->rp_size == 0) + c->bi.nospace_rp = 1; + smp_wmb(); + } else + ubifs_err(c, "cannot budget space, error %d", err); + return err; +} + +/** + * ubifs_release_budget - release budgeted free space. + * @c: UBIFS file-system description object + * @req: budget request + * + * This function releases the space budgeted by 'ubifs_budget_space()'. Note, + * since the index changes (which were budgeted for in @req->idx_growth) will + * only be written to the media on commit, this function moves the index budget + * from @c->bi.idx_growth to @c->bi.uncommitted_idx. The latter will be zeroed + * by the commit operation. + */ +void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req) +{ + ubifs_assert(c, req->new_page <= 1); + ubifs_assert(c, req->dirtied_page <= 1); + ubifs_assert(c, req->new_dent <= 1); + ubifs_assert(c, req->mod_dent <= 1); + ubifs_assert(c, req->new_ino <= 1); + ubifs_assert(c, req->new_ino_d <= UBIFS_MAX_INO_DATA); + ubifs_assert(c, req->dirtied_ino <= 4); + ubifs_assert(c, req->dirtied_ino_d <= UBIFS_MAX_INO_DATA * 4); + ubifs_assert(c, !(req->new_ino_d & 7)); + ubifs_assert(c, !(req->dirtied_ino_d & 7)); + if (!req->recalculate) { + ubifs_assert(c, req->idx_growth >= 0); + ubifs_assert(c, req->data_growth >= 0); + ubifs_assert(c, req->dd_growth >= 0); + } + + if (req->recalculate) { + req->data_growth = calc_data_growth(c, req); + req->dd_growth = calc_dd_growth(c, req); + req->idx_growth = calc_idx_growth(c, req); + } + + if (!req->data_growth && !req->dd_growth) + return; + + c->bi.nospace = c->bi.nospace_rp = 0; + smp_wmb(); + + spin_lock(&c->space_lock); + c->bi.idx_growth -= req->idx_growth; + c->bi.uncommitted_idx += req->idx_growth; + c->bi.data_growth -= req->data_growth; + c->bi.dd_growth -= req->dd_growth; + c->bi.min_idx_lebs = ubifs_calc_min_idx_lebs(c); + + ubifs_assert(c, c->bi.idx_growth >= 0); + ubifs_assert(c, c->bi.data_growth >= 0); + ubifs_assert(c, c->bi.dd_growth >= 0); + ubifs_assert(c, c->bi.min_idx_lebs < c->main_lebs); + ubifs_assert(c, !(c->bi.idx_growth & 7)); + ubifs_assert(c, !(c->bi.data_growth & 7)); + ubifs_assert(c, !(c->bi.dd_growth & 7)); + spin_unlock(&c->space_lock); +} + +/** + * ubifs_reported_space - calculate reported free space. + * @c: the UBIFS file-system description object + * @free: amount of free space + * + * This function calculates amount of free space which will be reported to + * user-space. User-space application tend to expect that if the file-system + * (e.g., via the 'statfs()' call) reports that it has N bytes available, they + * are able to write a file of size N. UBIFS attaches node headers to each data + * node and it has to write indexing nodes as well. This introduces additional + * overhead, and UBIFS has to report slightly less free space to meet the above + * expectations. + * + * This function assumes free space is made up of uncompressed data nodes and + * full index nodes (one per data node, tripled because we always allow enough + * space to write the index thrice). + * + * Note, the calculation is pessimistic, which means that most of the time + * UBIFS reports less space than it actually has. + */ +long long ubifs_reported_space(const struct ubifs_info *c, long long free) +{ + int divisor, factor, f; + + /* + * Reported space size is @free * X, where X is UBIFS block size + * divided by UBIFS block size + all overhead one data block + * introduces. The overhead is the node header + indexing overhead. + * + * Indexing overhead calculations are based on the following formula: + * I = N/(f - 1) + 1, where I - number of indexing nodes, N - number + * of data nodes, f - fanout. Because effective UBIFS fanout is twice + * as less than maximum fanout, we assume that each data node + * introduces 3 * @c->max_idx_node_sz / (@c->fanout/2 - 1) bytes. + * Note, the multiplier 3 is because UBIFS reserves thrice as more space + * for the index. + */ + f = c->fanout > 3 ? c->fanout >> 1 : 2; + factor = UBIFS_BLOCK_SIZE; + divisor = UBIFS_MAX_DATA_NODE_SZ; + divisor += (c->max_idx_node_sz * 3) / (f - 1); + free *= factor; + return div_u64(free, divisor); +} + +/** + * ubifs_get_free_space_nolock - return amount of free space. + * @c: UBIFS file-system description object + * + * This function calculates amount of free space to report to user-space. + * + * Because UBIFS may introduce substantial overhead (the index, node headers, + * alignment, wastage at the end of LEBs, etc), it cannot report real amount of + * free flash space it has (well, because not all dirty space is reclaimable, + * UBIFS does not actually know the real amount). If UBIFS did so, it would + * bread user expectations about what free space is. Users seem to accustomed + * to assume that if the file-system reports N bytes of free space, they would + * be able to fit a file of N bytes to the FS. This almost works for + * traditional file-systems, because they have way less overhead than UBIFS. + * So, to keep users happy, UBIFS tries to take the overhead into account. + */ +long long ubifs_get_free_space_nolock(struct ubifs_info *c) +{ + int rsvd_idx_lebs, lebs; + long long available, outstanding, free; + + ubifs_assert(c, c->bi.min_idx_lebs == ubifs_calc_min_idx_lebs(c)); + outstanding = c->bi.data_growth + c->bi.dd_growth; + available = ubifs_calc_available(c, c->bi.min_idx_lebs); + + /* + * When reporting free space to user-space, UBIFS guarantees that it is + * possible to write a file of free space size. This means that for + * empty LEBs we may use more precise calculations than + * 'ubifs_calc_available()' is using. Namely, we know that in empty + * LEBs we would waste only @c->leb_overhead bytes, not @c->dark_wm. + * Thus, amend the available space. + * + * Note, the calculations below are similar to what we have in + * 'do_budget_space()', so refer there for comments. + */ + if (c->bi.min_idx_lebs > c->lst.idx_lebs) + rsvd_idx_lebs = c->bi.min_idx_lebs - c->lst.idx_lebs; + else + rsvd_idx_lebs = 0; + lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt - + c->lst.taken_empty_lebs; + lebs -= rsvd_idx_lebs; + available += lebs * (c->dark_wm - c->leb_overhead); + + if (available > outstanding) + free = ubifs_reported_space(c, available - outstanding); + else + free = 0; + return free; +} diff --git a/ubifs-utils/libubifs/commit.c b/ubifs-utils/libubifs/commit.c new file mode 100644 index 0000000..f3b6113 --- /dev/null +++ b/ubifs-utils/libubifs/commit.c @@ -0,0 +1,383 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements functions that manage the running of the commit process. + * Each affected module has its own functions to accomplish their part in the + * commit and those functions are called here. + * + * The commit is the process whereby all updates to the index and LEB properties + * are written out together and the journal becomes empty. This keeps the + * file system consistent - at all times the state can be recreated by reading + * the index and LEB properties and then replaying the journal. + * + * The commit is split into two parts named "commit start" and "commit end". + * During commit start, the commit process has exclusive access to the journal + * by holding the commit semaphore down for writing. As few I/O operations as + * possible are performed during commit start, instead the nodes that are to be + * written are merely identified. During commit end, the commit semaphore is no + * longer held and the journal is again in operation, allowing users to continue + * to use the file system while the bulk of the commit I/O is performed. The + * purpose of this two-step approach is to prevent the commit from causing any + * latency blips. Note that in any case, the commit does not prevent lookups + * (as permitted by the TNC mutex), or access to VFS data structures e.g. page + * cache. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "debug.h" +#include "defs.h" +#include "misc.h" + +/* + * nothing_to_commit - check if there is nothing to commit. + * @c: UBIFS file-system description object + * + * This is a helper function which checks if there is anything to commit. It is + * used as an optimization to avoid starting the commit if it is not really + * necessary. Indeed, the commit operation always assumes flash I/O (e.g., + * writing the commit start node to the log), and it is better to avoid doing + * this unnecessarily. E.g., 'ubifs_sync_fs()' runs the commit, but if there is + * nothing to commit, it is more optimal to avoid any flash I/O. + * + * This function has to be called with @c->commit_sem locked for writing - + * this function does not take LPT/TNC locks because the @c->commit_sem + * guarantees that we have exclusive access to the TNC and LPT data structures. + * + * This function returns %1 if there is nothing to commit and %0 otherwise. + */ +static int nothing_to_commit(struct ubifs_info *c) +{ + /* + * During mounting or remounting from R/O mode to R/W mode we may + * commit for various recovery-related reasons. + */ + if (c->mounting || c->remounting_rw) + return 0; + + /* + * If the root TNC node is dirty, we definitely have something to + * commit. + */ + if (c->zroot.znode && ubifs_zn_dirty(c->zroot.znode)) + return 0; + + /* + * Increasing @c->dirty_pn_cnt/@c->dirty_nn_cnt and marking + * nnodes/pnodes as dirty in run_gc() could race with following + * checking, which leads inconsistent states between @c->nroot + * and @c->dirty_pn_cnt/@c->dirty_nn_cnt, holding @c->lp_mutex + * to avoid that. + */ + mutex_lock(&c->lp_mutex); + /* + * Even though the TNC is clean, the LPT tree may have dirty nodes. For + * example, this may happen if the budgeting subsystem invoked GC to + * make some free space, and the GC found an LEB with only dirty and + * free space. In this case GC would just change the lprops of this + * LEB (by turning all space into free space) and unmap it. + */ + if (c->nroot && test_bit(DIRTY_CNODE, &c->nroot->flags)) { + mutex_unlock(&c->lp_mutex); + return 0; + } + + ubifs_assert(c, atomic_long_read(&c->dirty_zn_cnt) == 0); + ubifs_assert(c, c->dirty_pn_cnt == 0); + ubifs_assert(c, c->dirty_nn_cnt == 0); + mutex_unlock(&c->lp_mutex); + + return 1; +} + +/** + * do_commit - commit the journal. + * @c: UBIFS file-system description object + * + * This function implements UBIFS commit. It has to be called with commit lock + * locked. Returns zero in case of success and a negative error code in case of + * failure. + */ +static int do_commit(struct ubifs_info *c) +{ + int err, new_ltail_lnum, old_ltail_lnum, i; + struct ubifs_zbranch zroot; + struct ubifs_lp_stats lst; + + dbg_cmt("start"); + ubifs_assert(c, !c->ro_media && !c->ro_mount); + + if (c->ro_error) { + err = -EROFS; + goto out_up; + } + + if (nothing_to_commit(c)) { + up_write(&c->commit_sem); + err = 0; + goto out_cancel; + } + + /* Sync all write buffers (necessary for recovery) */ + for (i = 0; i < c->jhead_cnt; i++) { + err = ubifs_wbuf_sync(&c->jheads[i].wbuf); + if (err) + goto out_up; + } + + c->cmt_no += 1; + err = ubifs_gc_start_commit(c); + if (err) + goto out_up; + err = dbg_check_lprops(c); + if (err) + goto out_up; + err = ubifs_log_start_commit(c, &new_ltail_lnum); + if (err) + goto out_up; + err = ubifs_tnc_start_commit(c, &zroot); + if (err) + goto out_up; + err = ubifs_lpt_start_commit(c); + if (err) + goto out_up; + err = ubifs_orphan_start_commit(c); + if (err) + goto out_up; + + ubifs_get_lp_stats(c, &lst); + + up_write(&c->commit_sem); + + err = ubifs_tnc_end_commit(c); + if (err) + goto out; + err = ubifs_lpt_end_commit(c); + if (err) + goto out; + err = ubifs_orphan_end_commit(c); + if (err) + goto out; + err = dbg_check_old_index(c, &zroot); + if (err) + goto out; + + c->mst_node->cmt_no = cpu_to_le64(c->cmt_no); + c->mst_node->log_lnum = cpu_to_le32(new_ltail_lnum); + c->mst_node->root_lnum = cpu_to_le32(zroot.lnum); + c->mst_node->root_offs = cpu_to_le32(zroot.offs); + c->mst_node->root_len = cpu_to_le32(zroot.len); + c->mst_node->ihead_lnum = cpu_to_le32(c->ihead_lnum); + c->mst_node->ihead_offs = cpu_to_le32(c->ihead_offs); + c->mst_node->index_size = cpu_to_le64(c->bi.old_idx_sz); + c->mst_node->lpt_lnum = cpu_to_le32(c->lpt_lnum); + c->mst_node->lpt_offs = cpu_to_le32(c->lpt_offs); + c->mst_node->nhead_lnum = cpu_to_le32(c->nhead_lnum); + c->mst_node->nhead_offs = cpu_to_le32(c->nhead_offs); + c->mst_node->ltab_lnum = cpu_to_le32(c->ltab_lnum); + c->mst_node->ltab_offs = cpu_to_le32(c->ltab_offs); + c->mst_node->lsave_lnum = cpu_to_le32(c->lsave_lnum); + c->mst_node->lsave_offs = cpu_to_le32(c->lsave_offs); + c->mst_node->lscan_lnum = cpu_to_le32(c->lscan_lnum); + c->mst_node->empty_lebs = cpu_to_le32(lst.empty_lebs); + c->mst_node->idx_lebs = cpu_to_le32(lst.idx_lebs); + c->mst_node->total_free = cpu_to_le64(lst.total_free); + c->mst_node->total_dirty = cpu_to_le64(lst.total_dirty); + c->mst_node->total_used = cpu_to_le64(lst.total_used); + c->mst_node->total_dead = cpu_to_le64(lst.total_dead); + c->mst_node->total_dark = cpu_to_le64(lst.total_dark); + if (c->no_orphs) + c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS); + else + c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_NO_ORPHS); + + old_ltail_lnum = c->ltail_lnum; + err = ubifs_log_end_commit(c, new_ltail_lnum); + if (err) + goto out; + + err = ubifs_log_post_commit(c, old_ltail_lnum); + if (err) + goto out; + err = ubifs_gc_end_commit(c); + if (err) + goto out; + err = ubifs_lpt_post_commit(c); + if (err) + goto out; + +out_cancel: + spin_lock(&c->cs_lock); + c->cmt_state = COMMIT_RESTING; + dbg_cmt("commit end"); + spin_unlock(&c->cs_lock); + return 0; + +out_up: + up_write(&c->commit_sem); +out: + ubifs_err(c, "commit failed, error %d", err); + spin_lock(&c->cs_lock); + c->cmt_state = COMMIT_BROKEN; + spin_unlock(&c->cs_lock); + ubifs_ro_mode(c, err); + return err; +} + +/** + * ubifs_commit_required - set commit state to "required". + * @c: UBIFS file-system description object + * + * This function is called if a commit is required but cannot be done from the + * calling function, so it is just flagged instead. + */ +void ubifs_commit_required(struct ubifs_info *c) +{ + spin_lock(&c->cs_lock); + switch (c->cmt_state) { + case COMMIT_RESTING: + case COMMIT_BACKGROUND: + dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state), + dbg_cstate(COMMIT_REQUIRED)); + c->cmt_state = COMMIT_REQUIRED; + break; + case COMMIT_RUNNING_BACKGROUND: + dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state), + dbg_cstate(COMMIT_RUNNING_REQUIRED)); + c->cmt_state = COMMIT_RUNNING_REQUIRED; + break; + case COMMIT_REQUIRED: + case COMMIT_RUNNING_REQUIRED: + case COMMIT_BROKEN: + break; + } + spin_unlock(&c->cs_lock); +} + +/** + * ubifs_request_bg_commit - notify the background thread to do a commit. + * @c: UBIFS file-system description object + * + * This function is called if the journal is full enough to make a commit + * worthwhile, so background thread is kicked to start it. + */ +void ubifs_request_bg_commit(__unused struct ubifs_info *c) +{ +} + +/** + * wait_for_commit - wait for commit. + * @c: UBIFS file-system description object + * + * This function sleeps until the commit operation is no longer running. + */ +static int wait_for_commit(struct ubifs_info *c) +{ + /* + * All commit operations are executed in synchronization context, + * so it is impossible that more than one threads doing commit. + */ + ubifs_assert(c, 0); + return 0; +} + +/** + * ubifs_run_commit - run or wait for commit. + * @c: UBIFS file-system description object + * + * This function runs commit and returns zero in case of success and a negative + * error code in case of failure. + */ +int ubifs_run_commit(struct ubifs_info *c) +{ + int err = 0; + + spin_lock(&c->cs_lock); + if (c->cmt_state == COMMIT_BROKEN) { + err = -EROFS; + goto out; + } + + if (c->cmt_state == COMMIT_RUNNING_BACKGROUND) + /* + * We set the commit state to 'running required' to indicate + * that we want it to complete as quickly as possible. + */ + c->cmt_state = COMMIT_RUNNING_REQUIRED; + + if (c->cmt_state == COMMIT_RUNNING_REQUIRED) { + spin_unlock(&c->cs_lock); + return wait_for_commit(c); + } + spin_unlock(&c->cs_lock); + + /* Ok, the commit is indeed needed */ + + down_write(&c->commit_sem); + spin_lock(&c->cs_lock); + /* + * Since we unlocked 'c->cs_lock', the state may have changed, so + * re-check it. + */ + if (c->cmt_state == COMMIT_BROKEN) { + err = -EROFS; + goto out_cmt_unlock; + } + + if (c->cmt_state == COMMIT_RUNNING_BACKGROUND) + c->cmt_state = COMMIT_RUNNING_REQUIRED; + + if (c->cmt_state == COMMIT_RUNNING_REQUIRED) { + up_write(&c->commit_sem); + spin_unlock(&c->cs_lock); + return wait_for_commit(c); + } + c->cmt_state = COMMIT_RUNNING_REQUIRED; + spin_unlock(&c->cs_lock); + + err = do_commit(c); + return err; + +out_cmt_unlock: + up_write(&c->commit_sem); +out: + spin_unlock(&c->cs_lock); + return err; +} + +/** + * ubifs_gc_should_commit - determine if it is time for GC to run commit. + * @c: UBIFS file-system description object + * + * This function is called by garbage collection to determine if commit should + * be run. If commit state is @COMMIT_BACKGROUND, which means that the journal + * is full enough to start commit, this function returns true. It is not + * absolutely necessary to commit yet, but it feels like this should be better + * then to keep doing GC. This function returns %1 if GC has to initiate commit + * and %0 if not. + */ +int ubifs_gc_should_commit(struct ubifs_info *c) +{ + int ret = 0; + + spin_lock(&c->cs_lock); + if (c->cmt_state == COMMIT_BACKGROUND) { + dbg_cmt("commit required now"); + c->cmt_state = COMMIT_REQUIRED; + } else + dbg_cmt("commit not requested"); + if (c->cmt_state == COMMIT_REQUIRED) + ret = 1; + spin_unlock(&c->cs_lock); + return ret; +} diff --git a/ubifs-utils/libubifs/debug.c b/ubifs-utils/libubifs/debug.c new file mode 100644 index 0000000..836cbc7 --- /dev/null +++ b/ubifs-utils/libubifs/debug.c @@ -0,0 +1,1033 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements most of the debugging stuff which is compiled in only + * when it is enabled. But some debugging check functions are implemented in + * corresponding subsystem, just because they are closely related and utilize + * various local functions of those subsystems. + */ + +#include <stdio.h> +#include <unistd.h> + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +static DEFINE_SPINLOCK(dbg_lock); + +static const char *get_key_fmt(int fmt) +{ + switch (fmt) { + case UBIFS_SIMPLE_KEY_FMT: + return "simple"; + default: + return "unknown/invalid format"; + } +} + +static const char *get_key_hash(int hash) +{ + switch (hash) { + case UBIFS_KEY_HASH_R5: + return "R5"; + case UBIFS_KEY_HASH_TEST: + return "test"; + default: + return "unknown/invalid name hash"; + } +} + +const char *ubifs_get_key_name(int type) +{ + switch (type) { + case UBIFS_INO_KEY: + return "inode"; + case UBIFS_DENT_KEY: + return "direntry"; + case UBIFS_XENT_KEY: + return "xentry"; + case UBIFS_DATA_KEY: + return "data"; + case UBIFS_TRUN_KEY: + return "truncate"; + default: + return "unknown/invalid key"; + } +} + +const char *ubifs_get_type_name(int type) +{ + switch (type) { + case UBIFS_ITYPE_REG: + return "file"; + case UBIFS_ITYPE_DIR: + return "dir"; + case UBIFS_ITYPE_LNK: + return "symlink"; + case UBIFS_ITYPE_BLK: + return "blkdev"; + case UBIFS_ITYPE_CHR: + return "char dev"; + case UBIFS_ITYPE_FIFO: + return "fifo"; + case UBIFS_ITYPE_SOCK: + return "socket"; + default: + return "unknown/invalid type"; + } +} + +const char *dbg_snprintf_key(const struct ubifs_info *c, + const union ubifs_key *key, char *buffer, int len) +{ + char *p = buffer; + int type = key_type(c, key); + + if (c->key_fmt == UBIFS_SIMPLE_KEY_FMT) { + switch (type) { + case UBIFS_INO_KEY: + len -= snprintf(p, len, "(%lu, %s)", + (unsigned long)key_inum(c, key), + ubifs_get_key_name(type)); + break; + case UBIFS_DENT_KEY: + case UBIFS_XENT_KEY: + len -= snprintf(p, len, "(%lu, %s, %#08x)", + (unsigned long)key_inum(c, key), + ubifs_get_key_name(type), + key_hash(c, key)); + break; + case UBIFS_DATA_KEY: + len -= snprintf(p, len, "(%lu, %s, %u)", + (unsigned long)key_inum(c, key), + ubifs_get_key_name(type), + key_block(c, key)); + break; + case UBIFS_TRUN_KEY: + len -= snprintf(p, len, "(%lu, %s)", + (unsigned long)key_inum(c, key), + ubifs_get_key_name(type)); + break; + default: + len -= snprintf(p, len, "(bad key type: %#08x, %#08x)", + key->u32[0], key->u32[1]); + } + } else + len -= snprintf(p, len, "bad key format %d", c->key_fmt); + ubifs_assert(c, len > 0); + return p; +} + +const char *dbg_ntype(int type) +{ + switch (type) { + case UBIFS_PAD_NODE: + return "padding node"; + case UBIFS_SB_NODE: + return "superblock node"; + case UBIFS_MST_NODE: + return "master node"; + case UBIFS_REF_NODE: + return "reference node"; + case UBIFS_INO_NODE: + return "inode node"; + case UBIFS_DENT_NODE: + return "direntry node"; + case UBIFS_XENT_NODE: + return "xentry node"; + case UBIFS_DATA_NODE: + return "data node"; + case UBIFS_TRUN_NODE: + return "truncate node"; + case UBIFS_IDX_NODE: + return "indexing node"; + case UBIFS_CS_NODE: + return "commit start node"; + case UBIFS_ORPH_NODE: + return "orphan node"; + case UBIFS_AUTH_NODE: + return "auth node"; + default: + return "unknown node"; + } +} + +static const char *dbg_gtype(int type) +{ + switch (type) { + case UBIFS_NO_NODE_GROUP: + return "no node group"; + case UBIFS_IN_NODE_GROUP: + return "in node group"; + case UBIFS_LAST_OF_NODE_GROUP: + return "last of node group"; + default: + return "unknown"; + } +} + +const char *dbg_cstate(int cmt_state) +{ + switch (cmt_state) { + case COMMIT_RESTING: + return "commit resting"; + case COMMIT_BACKGROUND: + return "background commit requested"; + case COMMIT_REQUIRED: + return "commit required"; + case COMMIT_RUNNING_BACKGROUND: + return "BACKGROUND commit running"; + case COMMIT_RUNNING_REQUIRED: + return "commit running and required"; + case COMMIT_BROKEN: + return "broken commit"; + default: + return "unknown commit state"; + } +} + +const char *dbg_jhead(int jhead) +{ + switch (jhead) { + case GCHD: + return "0 (GC)"; + case BASEHD: + return "1 (base)"; + case DATAHD: + return "2 (data)"; + default: + return "unknown journal head"; + } +} + +static void dump_ch(const struct ubifs_ch *ch) +{ + pr_err("\tmagic %#x\n", le32_to_cpu(ch->magic)); + pr_err("\tcrc %#x\n", le32_to_cpu(ch->crc)); + pr_err("\tnode_type %d (%s)\n", ch->node_type, + dbg_ntype(ch->node_type)); + pr_err("\tgroup_type %d (%s)\n", ch->group_type, + dbg_gtype(ch->group_type)); + pr_err("\tsqnum %llu\n", + (unsigned long long)le64_to_cpu(ch->sqnum)); + pr_err("\tlen %u\n", le32_to_cpu(ch->len)); +} + +void ubifs_dump_node(const struct ubifs_info *c, const void *node, int node_len) +{ + int i, n, type, safe_len, max_node_len, min_node_len; + union ubifs_key key; + const struct ubifs_ch *ch = node; + char key_buf[DBG_KEY_BUF_LEN]; + + /* If the magic is incorrect, just hexdump the first bytes */ + if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) { + pr_err("Not a node, first %zu bytes:", UBIFS_CH_SZ); + print_hex_dump("", DUMP_PREFIX_OFFSET, 32, 1, + (void *)node, UBIFS_CH_SZ, 1); + return; + } + + /* Skip dumping unknown type node */ + type = ch->node_type; + if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) { + pr_err("node type %d was not recognized\n", type); + return; + } + + spin_lock(&dbg_lock); + dump_ch(node); + + if (c->ranges[type].max_len == 0) { + max_node_len = min_node_len = c->ranges[type].len; + } else { + max_node_len = c->ranges[type].max_len; + min_node_len = c->ranges[type].min_len; + } + safe_len = le32_to_cpu(ch->len); + safe_len = safe_len > 0 ? safe_len : 0; + safe_len = min3(safe_len, max_node_len, node_len); + if (safe_len < min_node_len) { + pr_err("node len(%d) is too short for %s, left %d bytes:\n", + safe_len, dbg_ntype(type), + safe_len > UBIFS_CH_SZ ? + safe_len - (int)UBIFS_CH_SZ : 0); + if (safe_len > UBIFS_CH_SZ) + print_hex_dump("", DUMP_PREFIX_OFFSET, 32, 1, + (void *)node + UBIFS_CH_SZ, + safe_len - UBIFS_CH_SZ, 0); + goto out_unlock; + } + if (safe_len != le32_to_cpu(ch->len)) + pr_err("\ttruncated node length %d\n", safe_len); + + switch (type) { + case UBIFS_PAD_NODE: + { + const struct ubifs_pad_node *pad = node; + + pr_err("\tpad_len %u\n", le32_to_cpu(pad->pad_len)); + break; + } + case UBIFS_SB_NODE: + { + const struct ubifs_sb_node *sup = node; + unsigned int sup_flags = le32_to_cpu(sup->flags); + + pr_err("\tkey_hash %d (%s)\n", + (int)sup->key_hash, get_key_hash(sup->key_hash)); + pr_err("\tkey_fmt %d (%s)\n", + (int)sup->key_fmt, get_key_fmt(sup->key_fmt)); + pr_err("\tflags %#x\n", sup_flags); + pr_err("\tbig_lpt %u\n", + !!(sup_flags & UBIFS_FLG_BIGLPT)); + pr_err("\tspace_fixup %u\n", + !!(sup_flags & UBIFS_FLG_SPACE_FIXUP)); + pr_err("\tmin_io_size %u\n", le32_to_cpu(sup->min_io_size)); + pr_err("\tleb_size %u\n", le32_to_cpu(sup->leb_size)); + pr_err("\tleb_cnt %u\n", le32_to_cpu(sup->leb_cnt)); + pr_err("\tmax_leb_cnt %u\n", le32_to_cpu(sup->max_leb_cnt)); + pr_err("\tmax_bud_bytes %llu\n", + (unsigned long long)le64_to_cpu(sup->max_bud_bytes)); + pr_err("\tlog_lebs %u\n", le32_to_cpu(sup->log_lebs)); + pr_err("\tlpt_lebs %u\n", le32_to_cpu(sup->lpt_lebs)); + pr_err("\torph_lebs %u\n", le32_to_cpu(sup->orph_lebs)); + pr_err("\tjhead_cnt %u\n", le32_to_cpu(sup->jhead_cnt)); + pr_err("\tfanout %u\n", le32_to_cpu(sup->fanout)); + pr_err("\tlsave_cnt %u\n", le32_to_cpu(sup->lsave_cnt)); + pr_err("\tdefault_compr %u\n", + (int)le16_to_cpu(sup->default_compr)); + pr_err("\trp_size %llu\n", + (unsigned long long)le64_to_cpu(sup->rp_size)); + pr_err("\trp_uid %u\n", le32_to_cpu(sup->rp_uid)); + pr_err("\trp_gid %u\n", le32_to_cpu(sup->rp_gid)); + pr_err("\tfmt_version %u\n", le32_to_cpu(sup->fmt_version)); + pr_err("\ttime_gran %u\n", le32_to_cpu(sup->time_gran)); + pr_err("\tUUID %pUB\n", sup->uuid); + break; + } + case UBIFS_MST_NODE: + { + const struct ubifs_mst_node *mst = node; + + pr_err("\thighest_inum %llu\n", + (unsigned long long)le64_to_cpu(mst->highest_inum)); + pr_err("\tcommit number %llu\n", + (unsigned long long)le64_to_cpu(mst->cmt_no)); + pr_err("\tflags %#x\n", le32_to_cpu(mst->flags)); + pr_err("\tlog_lnum %u\n", le32_to_cpu(mst->log_lnum)); + pr_err("\troot_lnum %u\n", le32_to_cpu(mst->root_lnum)); + pr_err("\troot_offs %u\n", le32_to_cpu(mst->root_offs)); + pr_err("\troot_len %u\n", le32_to_cpu(mst->root_len)); + pr_err("\tgc_lnum %u\n", le32_to_cpu(mst->gc_lnum)); + pr_err("\tihead_lnum %u\n", le32_to_cpu(mst->ihead_lnum)); + pr_err("\tihead_offs %u\n", le32_to_cpu(mst->ihead_offs)); + pr_err("\tindex_size %llu\n", + (unsigned long long)le64_to_cpu(mst->index_size)); + pr_err("\tlpt_lnum %u\n", le32_to_cpu(mst->lpt_lnum)); + pr_err("\tlpt_offs %u\n", le32_to_cpu(mst->lpt_offs)); + pr_err("\tnhead_lnum %u\n", le32_to_cpu(mst->nhead_lnum)); + pr_err("\tnhead_offs %u\n", le32_to_cpu(mst->nhead_offs)); + pr_err("\tltab_lnum %u\n", le32_to_cpu(mst->ltab_lnum)); + pr_err("\tltab_offs %u\n", le32_to_cpu(mst->ltab_offs)); + pr_err("\tlsave_lnum %u\n", le32_to_cpu(mst->lsave_lnum)); + pr_err("\tlsave_offs %u\n", le32_to_cpu(mst->lsave_offs)); + pr_err("\tlscan_lnum %u\n", le32_to_cpu(mst->lscan_lnum)); + pr_err("\tleb_cnt %u\n", le32_to_cpu(mst->leb_cnt)); + pr_err("\tempty_lebs %u\n", le32_to_cpu(mst->empty_lebs)); + pr_err("\tidx_lebs %u\n", le32_to_cpu(mst->idx_lebs)); + pr_err("\ttotal_free %llu\n", + (unsigned long long)le64_to_cpu(mst->total_free)); + pr_err("\ttotal_dirty %llu\n", + (unsigned long long)le64_to_cpu(mst->total_dirty)); + pr_err("\ttotal_used %llu\n", + (unsigned long long)le64_to_cpu(mst->total_used)); + pr_err("\ttotal_dead %llu\n", + (unsigned long long)le64_to_cpu(mst->total_dead)); + pr_err("\ttotal_dark %llu\n", + (unsigned long long)le64_to_cpu(mst->total_dark)); + break; + } + case UBIFS_REF_NODE: + { + const struct ubifs_ref_node *ref = node; + + pr_err("\tlnum %u\n", le32_to_cpu(ref->lnum)); + pr_err("\toffs %u\n", le32_to_cpu(ref->offs)); + pr_err("\tjhead %u\n", le32_to_cpu(ref->jhead)); + break; + } + case UBIFS_INO_NODE: + { + const struct ubifs_ino_node *ino = node; + + key_read(c, &ino->key, &key); + pr_err("\tkey %s\n", + dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN)); + pr_err("\tcreat_sqnum %llu\n", + (unsigned long long)le64_to_cpu(ino->creat_sqnum)); + pr_err("\tsize %llu\n", + (unsigned long long)le64_to_cpu(ino->size)); + pr_err("\tnlink %u\n", le32_to_cpu(ino->nlink)); + pr_err("\tatime %lld.%u\n", + (long long)le64_to_cpu(ino->atime_sec), + le32_to_cpu(ino->atime_nsec)); + pr_err("\tmtime %lld.%u\n", + (long long)le64_to_cpu(ino->mtime_sec), + le32_to_cpu(ino->mtime_nsec)); + pr_err("\tctime %lld.%u\n", + (long long)le64_to_cpu(ino->ctime_sec), + le32_to_cpu(ino->ctime_nsec)); + pr_err("\tuid %u\n", le32_to_cpu(ino->uid)); + pr_err("\tgid %u\n", le32_to_cpu(ino->gid)); + pr_err("\tmode %u\n", le32_to_cpu(ino->mode)); + pr_err("\tflags %#x\n", le32_to_cpu(ino->flags)); + pr_err("\txattr_cnt %u\n", le32_to_cpu(ino->xattr_cnt)); + pr_err("\txattr_size %u\n", le32_to_cpu(ino->xattr_size)); + pr_err("\txattr_names %u\n", le32_to_cpu(ino->xattr_names)); + pr_err("\tcompr_type %#x\n", + (int)le16_to_cpu(ino->compr_type)); + pr_err("\tdata len %u\n", le32_to_cpu(ino->data_len)); + break; + } + case UBIFS_DENT_NODE: + case UBIFS_XENT_NODE: + { + const struct ubifs_dent_node *dent = node; + int nlen = le16_to_cpu(dent->nlen); + + key_read(c, &dent->key, &key); + pr_err("\tkey %s\n", + dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN)); + pr_err("\tinum %llu\n", + (unsigned long long)le64_to_cpu(dent->inum)); + pr_err("\ttype %d\n", (int)dent->type); + pr_err("\tnlen %d\n", nlen); + pr_err("\tname "); + + if (nlen > UBIFS_MAX_NLEN || + nlen > safe_len - UBIFS_DENT_NODE_SZ) + pr_err("(bad name length, not printing, bad or corrupted node)"); + else { + for (i = 0; i < nlen && dent->name[i]; i++) + pr_cont("%c", isprint(dent->name[i]) ? + dent->name[i] : '?'); + } + pr_cont("\n"); + + break; + } + case UBIFS_DATA_NODE: + { + const struct ubifs_data_node *dn = node; + + key_read(c, &dn->key, &key); + pr_err("\tkey %s\n", + dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN)); + pr_err("\tsize %u\n", le32_to_cpu(dn->size)); + pr_err("\tcompr_typ %d\n", + (int)le16_to_cpu(dn->compr_type)); + pr_err("\tdata size %u\n", + le32_to_cpu(ch->len) - (unsigned int)UBIFS_DATA_NODE_SZ); + pr_err("\tdata (length = %d):\n", + safe_len - (int)UBIFS_DATA_NODE_SZ); + print_hex_dump("\t", DUMP_PREFIX_OFFSET, 32, 1, + (void *)&dn->data, + safe_len - (int)UBIFS_DATA_NODE_SZ, 0); + break; + } + case UBIFS_TRUN_NODE: + { + const struct ubifs_trun_node *trun = node; + + pr_err("\tinum %u\n", le32_to_cpu(trun->inum)); + pr_err("\told_size %llu\n", + (unsigned long long)le64_to_cpu(trun->old_size)); + pr_err("\tnew_size %llu\n", + (unsigned long long)le64_to_cpu(trun->new_size)); + break; + } + case UBIFS_IDX_NODE: + { + const struct ubifs_idx_node *idx = node; + int max_child_cnt = (safe_len - UBIFS_IDX_NODE_SZ) / + (ubifs_idx_node_sz(c, 1) - + UBIFS_IDX_NODE_SZ); + + n = min_t(int, le16_to_cpu(idx->child_cnt), max_child_cnt); + pr_err("\tchild_cnt %d\n", (int)le16_to_cpu(idx->child_cnt)); + pr_err("\tlevel %d\n", (int)le16_to_cpu(idx->level)); + pr_err("\tBranches:\n"); + + for (i = 0; i < n && i < c->fanout; i++) { + const struct ubifs_branch *br; + + br = ubifs_idx_branch(c, idx, i); + key_read(c, &br->key, &key); + pr_err("\t%d: LEB %d:%d len %d key %s\n", + i, le32_to_cpu(br->lnum), le32_to_cpu(br->offs), + le32_to_cpu(br->len), + dbg_snprintf_key(c, &key, key_buf, + DBG_KEY_BUF_LEN)); + } + break; + } + case UBIFS_CS_NODE: + break; + case UBIFS_ORPH_NODE: + { + const struct ubifs_orph_node *orph = node; + + pr_err("\tcommit number %llu\n", + (unsigned long long) + le64_to_cpu(orph->cmt_no) & LLONG_MAX); + pr_err("\tlast node flag %llu\n", + (unsigned long long)(le64_to_cpu(orph->cmt_no)) >> 63); + n = (safe_len - UBIFS_ORPH_NODE_SZ) >> 3; + pr_err("\t%d orphan inode numbers:\n", n); + for (i = 0; i < n; i++) + pr_err("\t ino %llu\n", + (unsigned long long)le64_to_cpu(orph->inos[i])); + break; + } + case UBIFS_AUTH_NODE: + { + break; + } + default: + pr_err("node type %d was not recognized\n", type); + } + +out_unlock: + spin_unlock(&dbg_lock); +} + +void ubifs_dump_lstats(const struct ubifs_lp_stats *lst) +{ + spin_lock(&dbg_lock); + pr_err("(pid %d) Lprops statistics: empty_lebs %d, idx_lebs %d\n", + getpid(), lst->empty_lebs, lst->idx_lebs); + pr_err("\ttaken_empty_lebs %d, total_free %lld, total_dirty %lld\n", + lst->taken_empty_lebs, lst->total_free, lst->total_dirty); + pr_err("\ttotal_used %lld, total_dark %lld, total_dead %lld\n", + lst->total_used, lst->total_dark, lst->total_dead); + spin_unlock(&dbg_lock); +} + +void ubifs_dump_budg(struct ubifs_info *c, const struct ubifs_budg_info *bi) +{ + int i; + struct rb_node *rb; + struct ubifs_bud *bud; + struct ubifs_gced_idx_leb *idx_gc; + long long available, outstanding, free; + + spin_lock(&c->space_lock); + spin_lock(&dbg_lock); + pr_err("(pid %d) Budgeting info: data budget sum %lld, total budget sum %lld\n", + getpid(), bi->data_growth + bi->dd_growth, + bi->data_growth + bi->dd_growth + bi->idx_growth); + pr_err("\tbudg_data_growth %lld, budg_dd_growth %lld, budg_idx_growth %lld\n", + bi->data_growth, bi->dd_growth, bi->idx_growth); + pr_err("\tmin_idx_lebs %d, old_idx_sz %llu, uncommitted_idx %lld\n", + bi->min_idx_lebs, bi->old_idx_sz, bi->uncommitted_idx); + pr_err("\tpage_budget %d, inode_budget %d, dent_budget %d\n", + bi->page_budget, bi->inode_budget, bi->dent_budget); + pr_err("\tnospace %u, nospace_rp %u\n", bi->nospace, bi->nospace_rp); + pr_err("\tdark_wm %d, dead_wm %d, max_idx_node_sz %d\n", + c->dark_wm, c->dead_wm, c->max_idx_node_sz); + + if (bi != &c->bi) + /* + * If we are dumping saved budgeting data, do not print + * additional information which is about the current state, not + * the old one which corresponded to the saved budgeting data. + */ + goto out_unlock; + + pr_err("\tfreeable_cnt %d, calc_idx_sz %lld, idx_gc_cnt %d\n", + c->freeable_cnt, c->calc_idx_sz, c->idx_gc_cnt); + pr_err("\tdirty_pg_cnt %ld, dirty_zn_cnt %ld, clean_zn_cnt %ld\n", + atomic_long_read(&c->dirty_pg_cnt), + atomic_long_read(&c->dirty_zn_cnt), + atomic_long_read(&c->clean_zn_cnt)); + pr_err("\tgc_lnum %d, ihead_lnum %d\n", c->gc_lnum, c->ihead_lnum); + + /* If we are in R/O mode, journal heads do not exist */ + if (c->jheads) + for (i = 0; i < c->jhead_cnt; i++) + pr_err("\tjhead %s\t LEB %d\n", + dbg_jhead(c->jheads[i].wbuf.jhead), + c->jheads[i].wbuf.lnum); + for (rb = rb_first(&c->buds); rb; rb = rb_next(rb)) { + bud = rb_entry(rb, struct ubifs_bud, rb); + pr_err("\tbud LEB %d\n", bud->lnum); + } + list_for_each_entry(bud, &c->old_buds, list) + pr_err("\told bud LEB %d\n", bud->lnum); + list_for_each_entry(idx_gc, &c->idx_gc, list) + pr_err("\tGC'ed idx LEB %d unmap %d\n", + idx_gc->lnum, idx_gc->unmap); + pr_err("\tcommit state %d\n", c->cmt_state); + + /* Print budgeting predictions */ + available = ubifs_calc_available(c, c->bi.min_idx_lebs); + outstanding = c->bi.data_growth + c->bi.dd_growth; + free = ubifs_get_free_space_nolock(c); + pr_err("Budgeting predictions:\n"); + pr_err("\tavailable: %lld, outstanding %lld, free %lld\n", + available, outstanding, free); +out_unlock: + spin_unlock(&dbg_lock); + spin_unlock(&c->space_lock); +} + +void ubifs_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp) +{ + int i, spc, dark = 0, dead = 0; + struct rb_node *rb; + struct ubifs_bud *bud; + + spc = lp->free + lp->dirty; + if (spc < c->dead_wm) + dead = spc; + else + dark = ubifs_calc_dark(c, spc); + + if (lp->flags & LPROPS_INDEX) + pr_err("LEB %-7d free %-8d dirty %-8d used %-8d free + dirty %-8d flags %#x (", + lp->lnum, lp->free, lp->dirty, c->leb_size - spc, spc, + lp->flags); + else + pr_err("LEB %-7d free %-8d dirty %-8d used %-8d free + dirty %-8d dark %-4d dead %-4d nodes fit %-3d flags %#-4x (", + lp->lnum, lp->free, lp->dirty, c->leb_size - spc, spc, + dark, dead, (int)(spc / UBIFS_MAX_NODE_SZ), lp->flags); + + if (lp->flags & LPROPS_TAKEN) { + if (lp->flags & LPROPS_INDEX) + pr_cont("index, taken"); + else + pr_cont("taken"); + } else { + const char *s; + + if (lp->flags & LPROPS_INDEX) { + switch (lp->flags & LPROPS_CAT_MASK) { + case LPROPS_DIRTY_IDX: + s = "dirty index"; + break; + case LPROPS_FRDI_IDX: + s = "freeable index"; + break; + default: + s = "index"; + } + } else { + switch (lp->flags & LPROPS_CAT_MASK) { + case LPROPS_UNCAT: + s = "not categorized"; + break; + case LPROPS_DIRTY: + s = "dirty"; + break; + case LPROPS_FREE: + s = "free"; + break; + case LPROPS_EMPTY: + s = "empty"; + break; + case LPROPS_FREEABLE: + s = "freeable"; + break; + default: + s = NULL; + break; + } + } + pr_cont("%s", s); + } + + for (rb = rb_first((struct rb_root *)&c->buds); rb; rb = rb_next(rb)) { + bud = rb_entry(rb, struct ubifs_bud, rb); + if (bud->lnum == lp->lnum) { + int head = 0; + for (i = 0; i < c->jhead_cnt; i++) { + /* + * Note, if we are in R/O mode or in the middle + * of mounting/re-mounting, the write-buffers do + * not exist. + */ + if (c->jheads && + lp->lnum == c->jheads[i].wbuf.lnum) { + pr_cont(", jhead %s", dbg_jhead(i)); + head = 1; + } + } + if (!head) + pr_cont(", bud of jhead %s", + dbg_jhead(bud->jhead)); + } + } + if (lp->lnum == c->gc_lnum) + pr_cont(", GC LEB"); + pr_cont(")\n"); +} + +void ubifs_dump_lprops(struct ubifs_info *c) +{ + int lnum, err; + struct ubifs_lprops lp; + struct ubifs_lp_stats lst; + + pr_err("(pid %d) start dumping LEB properties\n", getpid()); + ubifs_get_lp_stats(c, &lst); + ubifs_dump_lstats(&lst); + + for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) { + err = ubifs_read_one_lp(c, lnum, &lp); + if (err) { + ubifs_err(c, "cannot read lprops for LEB %d", lnum); + continue; + } + + ubifs_dump_lprop(c, &lp); + } + pr_err("(pid %d) finish dumping LEB properties\n", getpid()); +} + +void ubifs_dump_lpt_info(struct ubifs_info *c) +{ + int i; + + spin_lock(&dbg_lock); + pr_err("(pid %d) dumping LPT information\n", getpid()); + pr_err("\tlpt_sz: %lld\n", c->lpt_sz); + pr_err("\tpnode_sz: %d\n", c->pnode_sz); + pr_err("\tnnode_sz: %d\n", c->nnode_sz); + pr_err("\tltab_sz: %d\n", c->ltab_sz); + pr_err("\tlsave_sz: %d\n", c->lsave_sz); + pr_err("\tbig_lpt: %u\n", c->big_lpt); + pr_err("\tlpt_hght: %d\n", c->lpt_hght); + pr_err("\tpnode_cnt: %d\n", c->pnode_cnt); + pr_err("\tnnode_cnt: %d\n", c->nnode_cnt); + pr_err("\tdirty_pn_cnt: %d\n", c->dirty_pn_cnt); + pr_err("\tdirty_nn_cnt: %d\n", c->dirty_nn_cnt); + pr_err("\tlsave_cnt: %d\n", c->lsave_cnt); + pr_err("\tspace_bits: %d\n", c->space_bits); + pr_err("\tlpt_lnum_bits: %d\n", c->lpt_lnum_bits); + pr_err("\tlpt_offs_bits: %d\n", c->lpt_offs_bits); + pr_err("\tlpt_spc_bits: %d\n", c->lpt_spc_bits); + pr_err("\tpcnt_bits: %d\n", c->pcnt_bits); + pr_err("\tlnum_bits: %d\n", c->lnum_bits); + pr_err("\tLPT root is at %d:%d\n", c->lpt_lnum, c->lpt_offs); + pr_err("\tLPT head is at %d:%d\n", + c->nhead_lnum, c->nhead_offs); + pr_err("\tLPT ltab is at %d:%d\n", c->ltab_lnum, c->ltab_offs); + if (c->big_lpt) + pr_err("\tLPT lsave is at %d:%d\n", + c->lsave_lnum, c->lsave_offs); + for (i = 0; i < c->lpt_lebs; i++) + pr_err("\tLPT LEB %d free %d dirty %d tgc %d cmt %d\n", + i + c->lpt_first, c->ltab[i].free, c->ltab[i].dirty, + c->ltab[i].tgc, c->ltab[i].cmt); + spin_unlock(&dbg_lock); +} + +void ubifs_dump_leb(const struct ubifs_info *c, int lnum) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + void *buf; + + pr_err("(pid %d) start dumping LEB %d\n", getpid(), lnum); + + buf = __vmalloc(c->leb_size, GFP_NOFS); + if (!buf) { + ubifs_err(c, "cannot allocate memory for dumping LEB %d", lnum); + return; + } + + sleb = ubifs_scan(c, lnum, 0, buf, 0); + if (IS_ERR(sleb)) { + ubifs_err(c, "scan error %d", (int)PTR_ERR(sleb)); + goto out; + } + + pr_err("LEB %d has %d nodes ending at %d\n", lnum, + sleb->nodes_cnt, sleb->endpt); + + list_for_each_entry(snod, &sleb->nodes, list) { + cond_resched(); + pr_err("Dumping node at LEB %d:%d len %d\n", lnum, + snod->offs, snod->len); + ubifs_dump_node(c, snod->node, c->leb_size - snod->offs); + } + + pr_err("(pid %d) finish dumping LEB %d\n", getpid(), lnum); + ubifs_scan_destroy(sleb); + +out: + vfree(buf); + return; +} + +void ubifs_dump_znode(const struct ubifs_info *c, + const struct ubifs_znode *znode) +{ + int n; + const struct ubifs_zbranch *zbr; + char key_buf[DBG_KEY_BUF_LEN]; + + spin_lock(&dbg_lock); + if (znode->parent) + zbr = &znode->parent->zbranch[znode->iip]; + else + zbr = &c->zroot; + + pr_err("znode %p, LEB %d:%d len %d parent %p iip %d level %d child_cnt %d flags %lx\n", + znode, zbr->lnum, zbr->offs, zbr->len, znode->parent, znode->iip, + znode->level, znode->child_cnt, znode->flags); + + if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) { + spin_unlock(&dbg_lock); + return; + } + + pr_err("zbranches:\n"); + for (n = 0; n < znode->child_cnt; n++) { + zbr = &znode->zbranch[n]; + if (znode->level > 0) + pr_err("\t%d: znode %p LEB %d:%d len %d key %s\n", + n, zbr->znode, zbr->lnum, zbr->offs, zbr->len, + dbg_snprintf_key(c, &zbr->key, key_buf, + DBG_KEY_BUF_LEN)); + else + pr_err("\t%d: LNC %p LEB %d:%d len %d key %s\n", + n, zbr->znode, zbr->lnum, zbr->offs, zbr->len, + dbg_snprintf_key(c, &zbr->key, key_buf, + DBG_KEY_BUF_LEN)); + } + spin_unlock(&dbg_lock); +} + +void ubifs_dump_heap(__unused struct ubifs_info *c, struct ubifs_lpt_heap *heap, + int cat) +{ + int i; + + pr_err("(pid %d) start dumping heap cat %d (%d elements)\n", + getpid(), cat, heap->cnt); + for (i = 0; i < heap->cnt; i++) { + struct ubifs_lprops *lprops = heap->arr[i]; + + pr_err("\t%d. LEB %d hpos %d free %d dirty %d flags %d\n", + i, lprops->lnum, lprops->hpos, lprops->free, + lprops->dirty, lprops->flags); + } + pr_err("(pid %d) finish dumping heap\n", getpid()); +} + +void ubifs_dump_pnode(__unused struct ubifs_info *c, struct ubifs_pnode *pnode, + struct ubifs_nnode *parent, int iip) +{ + int i; + + pr_err("(pid %d) dumping pnode:\n", getpid()); + pr_err("\taddress %zx parent %zx cnext %zx\n", + (size_t)pnode, (size_t)parent, (size_t)pnode->cnext); + pr_err("\tflags %lu iip %d level %d num %d\n", + pnode->flags, iip, pnode->level, pnode->num); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_lprops *lp = &pnode->lprops[i]; + + pr_err("\t%d: free %d dirty %d flags %d lnum %d\n", + i, lp->free, lp->dirty, lp->flags, lp->lnum); + } +} + +/** + * dbg_walk_index - walk the on-flash index. + * @c: UBIFS file-system description object + * @leaf_cb: called for each leaf node + * @znode_cb: called for each indexing node + * @priv: private data which is passed to callbacks + * + * This function walks the UBIFS index and calls the @leaf_cb for each leaf + * node and @znode_cb for each indexing node. Returns zero in case of success + * and a negative error code in case of failure. + * + * It would be better if this function removed every znode it pulled to into + * the TNC, so that the behavior more closely matched the non-debugging + * behavior. + */ +int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb, + dbg_znode_callback znode_cb, void *priv) +{ + int err; + struct ubifs_zbranch *zbr; + struct ubifs_znode *znode, *child; + + mutex_lock(&c->tnc_mutex); + /* If the root indexing node is not in TNC - pull it */ + if (!c->zroot.znode) { + c->zroot.znode = ubifs_load_znode(c, &c->zroot, NULL, 0); + if (IS_ERR(c->zroot.znode)) { + err = PTR_ERR(c->zroot.znode); + c->zroot.znode = NULL; + goto out_unlock; + } + } + + /* + * We are going to traverse the indexing tree in the postorder manner. + * Go down and find the leftmost indexing node where we are going to + * start from. + */ + znode = c->zroot.znode; + while (znode->level > 0) { + zbr = &znode->zbranch[0]; + child = zbr->znode; + if (!child) { + child = ubifs_load_znode(c, zbr, znode, 0); + if (IS_ERR(child)) { + err = PTR_ERR(child); + goto out_unlock; + } + } + + znode = child; + } + + /* Iterate over all indexing nodes */ + while (1) { + int idx; + + cond_resched(); + + if (znode_cb) { + err = znode_cb(c, znode, priv); + if (err) { + ubifs_err(c, "znode checking function returned error %d", + err); + ubifs_dump_znode(c, znode); + goto out_dump; + } + } + if (leaf_cb && znode->level == 0) { + for (idx = 0; idx < znode->child_cnt; idx++) { + zbr = &znode->zbranch[idx]; + err = leaf_cb(c, zbr, priv); + if (err) { + ubifs_err(c, "leaf checking function returned error %d, for leaf at LEB %d:%d", + err, zbr->lnum, zbr->offs); + goto out_dump; + } + } + } + + if (!znode->parent) + break; + + idx = znode->iip + 1; + znode = znode->parent; + if (idx < znode->child_cnt) { + /* Switch to the next index in the parent */ + zbr = &znode->zbranch[idx]; + child = zbr->znode; + if (!child) { + child = ubifs_load_znode(c, zbr, znode, idx); + if (IS_ERR(child)) { + err = PTR_ERR(child); + goto out_unlock; + } + zbr->znode = child; + } + znode = child; + } else + /* + * This is the last child, switch to the parent and + * continue. + */ + continue; + + /* Go to the lowest leftmost znode in the new sub-tree */ + while (znode->level > 0) { + zbr = &znode->zbranch[0]; + child = zbr->znode; + if (!child) { + child = ubifs_load_znode(c, zbr, znode, 0); + if (IS_ERR(child)) { + err = PTR_ERR(child); + goto out_unlock; + } + zbr->znode = child; + } + znode = child; + } + } + + mutex_unlock(&c->tnc_mutex); + return 0; + +out_dump: + if (znode->parent) + zbr = &znode->parent->zbranch[znode->iip]; + else + zbr = &c->zroot; + ubifs_msg(c, "dump of znode at LEB %d:%d", zbr->lnum, zbr->offs); + ubifs_dump_znode(c, znode); +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * add_size - add znode size to partially calculated index size. + * @c: UBIFS file-system description object + * @znode: znode to add size for + * @priv: partially calculated index size + * + * This is a helper function for 'dbg_check_idx_size()' which is called for + * every indexing node and adds its size to the 'long long' variable pointed to + * by @priv. + */ +int add_size(struct ubifs_info *c, struct ubifs_znode *znode, void *priv) +{ + long long *idx_size = priv; + int add; + + add = ubifs_idx_node_sz(c, znode->child_cnt); + add = ALIGN(add, 8); + *idx_size += add; + return 0; +} + +void ubifs_assert_failed(struct ubifs_info *c, const char *expr, + const char *file, int line) +{ + ubifs_err(c, "UBIFS assert failed: %s, in %s:%u", expr, file, line); + + /* + * Different from linux kernel. + * Invoke callback function if there is one, otherwise make filesystem + * readonly when assertion is failed. + */ + if (c->assert_failed_cb) + c->assert_failed_cb(c); + else + ubifs_ro_mode(c, -EINVAL); +} diff --git a/ubifs-utils/libubifs/debug.h b/ubifs-utils/libubifs/debug.h new file mode 100644 index 0000000..c4aa59d --- /dev/null +++ b/ubifs-utils/libubifs/debug.h @@ -0,0 +1,172 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +#ifndef __UBIFS_DEBUG_H__ +#define __UBIFS_DEBUG_H__ + +/* Checking helper functions */ +typedef int (*dbg_leaf_callback)(struct ubifs_info *c, + struct ubifs_zbranch *zbr, void *priv); +typedef int (*dbg_znode_callback)(struct ubifs_info *c, + struct ubifs_znode *znode, void *priv); + +void ubifs_assert_failed(struct ubifs_info *c, const char *expr, + const char *file, int line); + +#define ubifs_assert(c, expr) do { \ + if (unlikely(!(expr))) { \ + ubifs_assert_failed((struct ubifs_info *)c, #expr, __FILE__, \ + __LINE__); \ + } \ +} while (0) + +#define ubifs_assert_cmt_locked(c) do { \ + if (unlikely(down_write_trylock(&(c)->commit_sem))) { \ + up_write(&(c)->commit_sem); \ + ubifs_err(c, "commit lock is not locked!\n"); \ + ubifs_assert(c, 0); \ + } \ +} while (0) + +#define ubifs_dbg_msg(type, fmt, ...) \ + pr_debug("UBIFS DBG " type " " fmt "\n", ##__VA_ARGS__) + +#define DBG_KEY_BUF_LEN 48 +#define ubifs_dbg_msg_key(type, key, fmt, ...) do { \ + char __tmp_key_buf[DBG_KEY_BUF_LEN]; \ + pr_debug("UBIFS DBG " type " " fmt "%s\n", ##__VA_ARGS__, \ + dbg_snprintf_key(c, key, __tmp_key_buf, DBG_KEY_BUF_LEN)); \ +} while (0) + +/* General messages */ +#define dbg_gen(fmt, ...) ubifs_dbg_msg("gen", fmt, ##__VA_ARGS__) +/* Additional journal messages */ +#define dbg_jnl(fmt, ...) ubifs_dbg_msg("jnl", fmt, ##__VA_ARGS__) +#define dbg_jnlk(key, fmt, ...) \ + ubifs_dbg_msg_key("jnl", key, fmt, ##__VA_ARGS__) +/* Additional TNC messages */ +#define dbg_tnc(fmt, ...) ubifs_dbg_msg("tnc", fmt, ##__VA_ARGS__) +#define dbg_tnck(key, fmt, ...) \ + ubifs_dbg_msg_key("tnc", key, fmt, ##__VA_ARGS__) +/* Additional lprops messages */ +#define dbg_lp(fmt, ...) ubifs_dbg_msg("lp", fmt, ##__VA_ARGS__) +/* Additional LEB find messages */ +#define dbg_find(fmt, ...) ubifs_dbg_msg("find", fmt, ##__VA_ARGS__) +/* Additional mount messages */ +#define dbg_mnt(fmt, ...) ubifs_dbg_msg("mnt", fmt, ##__VA_ARGS__) +#define dbg_mntk(key, fmt, ...) \ + ubifs_dbg_msg_key("mnt", key, fmt, ##__VA_ARGS__) +/* Additional I/O messages */ +#define dbg_io(fmt, ...) ubifs_dbg_msg("io", fmt, ##__VA_ARGS__) +/* Additional commit messages */ +#define dbg_cmt(fmt, ...) ubifs_dbg_msg("cmt", fmt, ##__VA_ARGS__) +/* Additional budgeting messages */ +#define dbg_budg(fmt, ...) ubifs_dbg_msg("budg", fmt, ##__VA_ARGS__) +/* Additional log messages */ +#define dbg_log(fmt, ...) ubifs_dbg_msg("log", fmt, ##__VA_ARGS__) +/* Additional gc messages */ +#define dbg_gc(fmt, ...) ubifs_dbg_msg("gc", fmt, ##__VA_ARGS__) +/* Additional scan messages */ +#define dbg_scan(fmt, ...) ubifs_dbg_msg("scan", fmt, ##__VA_ARGS__) +/* Additional recovery messages */ +#define dbg_rcvry(fmt, ...) ubifs_dbg_msg("rcvry", fmt, ##__VA_ARGS__) +/* Additional fsck messages */ +#define dbg_fsck(fmt, ...) ubifs_dbg_msg("fsck", fmt, ##__VA_ARGS__) + +static inline int dbg_is_chk_index(__unused const struct ubifs_info *c) +{ return 0; } + +/* Dump functions */ +const char *ubifs_get_key_name(int type); +const char *ubifs_get_type_name(int type); +const char *dbg_ntype(int type); +const char *dbg_cstate(int cmt_state); +const char *dbg_jhead(int jhead); +const char *dbg_get_key_dump(const struct ubifs_info *c, + const union ubifs_key *key); +const char *dbg_snprintf_key(const struct ubifs_info *c, + const union ubifs_key *key, char *buffer, int len); +void ubifs_dump_node(const struct ubifs_info *c, const void *node, + int node_len); +void ubifs_dump_lstats(const struct ubifs_lp_stats *lst); +void ubifs_dump_budg(struct ubifs_info *c, const struct ubifs_budg_info *bi); +void ubifs_dump_lprop(const struct ubifs_info *c, + const struct ubifs_lprops *lp); +void ubifs_dump_lprops(struct ubifs_info *c); +void ubifs_dump_lpt_info(struct ubifs_info *c); +void ubifs_dump_leb(const struct ubifs_info *c, int lnum); +void ubifs_dump_znode(const struct ubifs_info *c, + const struct ubifs_znode *znode); +void ubifs_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, + int cat); +void ubifs_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode, + struct ubifs_nnode *parent, int iip); +void ubifs_dump_index(struct ubifs_info *c); +void ubifs_dump_lpt_lebs(const struct ubifs_info *c); + +int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb, + dbg_znode_callback znode_cb, void *priv); +int add_size(struct ubifs_info *c, struct ubifs_znode *znode, void *priv); + +/* Checking functions */ +static inline void dbg_save_space_info(__unused struct ubifs_info *c) {} +static inline int dbg_check_space_info(__unused struct ubifs_info *c) +{ return 0; } +static inline int dbg_check_lprops(__unused struct ubifs_info *c) { return 0; } +static inline int dbg_old_index_check_init(__unused struct ubifs_info *c, + __unused struct ubifs_zbranch *zroot) +{ return 0; } +static inline int dbg_check_old_index(__unused struct ubifs_info *c, + __unused struct ubifs_zbranch *zroot) +{ return 0; } +static inline int dbg_check_cats(__unused struct ubifs_info *c) { return 0; } +static inline int dbg_check_ltab(__unused struct ubifs_info *c) { return 0; } +static inline int dbg_chk_lpt_free_spc(__unused struct ubifs_info *c) +{ return 0; } +static inline int dbg_chk_lpt_sz(__unused struct ubifs_info *c, + __unused int action, __unused int len) +{ return 0; } +static inline int dbg_check_tnc(__unused struct ubifs_info *c, + __unused int extra) { return 0; } +static inline int dbg_check_idx_size(__unused struct ubifs_info *c, + __unused long long idx_size) { return 0; } +static inline int dbg_check_filesystem(__unused struct ubifs_info *c) +{ return 0; } +static inline void dbg_check_heap(__unused struct ubifs_info *c, + __unused struct ubifs_lpt_heap *heap, + __unused int cat, + __unused int add_pos) {} +static inline int dbg_check_lpt_nodes(__unused struct ubifs_info *c, + __unused struct ubifs_cnode *cnode, + __unused int row, + __unused int col) { return 0; } +static inline int dbg_check_data_nodes_order(__unused struct ubifs_info *c, + __unused struct list_head *head) +{ return 0; } +static inline int dbg_check_nondata_nodes_order(__unused struct ubifs_info *c, + __unused struct list_head *head) +{ return 0; } +static inline int dbg_leb_write(__unused struct ubifs_info *c, + __unused int lnum, __unused const void *buf, + __unused int offs, __unused int len) +{ return 0; } +static inline int dbg_leb_change(__unused struct ubifs_info *c, + __unused int lnum, __unused const void *buf, + __unused int len) { return 0; } +static inline int dbg_leb_unmap(__unused struct ubifs_info *c, + __unused int lnum) { return 0; } +static inline int dbg_leb_map(__unused struct ubifs_info *c, __unused int lnum) +{ return 0; } + +extern void print_hex_dump(const char *prefix_str, + int prefix_type, int rowsize, int groupsize, + const void *buf, size_t len, bool ascii); + +#endif /* !__UBIFS_DEBUG_H__ */ diff --git a/ubifs-utils/libubifs/dir.c b/ubifs-utils/libubifs/dir.c new file mode 100644 index 0000000..89f77eb --- /dev/null +++ b/ubifs-utils/libubifs/dir.c @@ -0,0 +1,390 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * Copyright (C) 2006, 2007 University of Szeged, Hungary + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + * Zoltan Sogor + */ + +/* + * This file implements directory operations. + * + * All FS operations in this file allocate budget before writing anything to the + * media. If they fail to allocate it, the error is returned. The only + * exceptions are 'ubifs_unlink()' and 'ubifs_rmdir()' which keep working even + * if they unable to allocate the budget, because deletion %-ENOSPC failure is + * not what users are usually ready to get. UBIFS budgeting subsystem has some + * space reserved for these purposes. + * + * All operations in this file write all inodes which they change straight + * away, instead of marking them dirty. For example, 'ubifs_link()' changes + * @i_size of the parent inode and writes the parent inode together with the + * target inode. This was done to simplify file-system recovery which would + * otherwise be very difficult to do. The only exception is rename which marks + * the re-named inode dirty (because its @i_ctime is updated) but does not + * write it, but just marks it as dirty. + */ + +#include <sys/stat.h> + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/** + * inherit_flags - inherit flags of the parent inode. + * @c: UBIFS file-system description object + * @dir: parent inode + * @mode: new inode mode flags + * + * This is a helper function for 'ubifs_new_inode()' which inherits flag of the + * parent directory inode @dir. UBIFS inodes inherit the following flags: + * o %UBIFS_COMPR_FL, which is useful to switch compression on/of on + * sub-directory basis; + * o %UBIFS_SYNC_FL - useful for the same reasons; + * o %UBIFS_DIRSYNC_FL - similar, but relevant only to directories. + * + * This function returns the inherited flags. + */ +static int inherit_flags(struct ubifs_info *c, const struct inode *dir, + unsigned int mode) +{ + int flags; + const struct ubifs_inode *ui = ubifs_inode(dir); + + ubifs_assert(c, S_ISDIR(dir->mode)); + + flags = ui->flags & (UBIFS_COMPR_FL | UBIFS_SYNC_FL | UBIFS_DIRSYNC_FL); + if (!S_ISDIR(mode)) + /* The "DIRSYNC" flag only applies to directories */ + flags &= ~UBIFS_DIRSYNC_FL; + return flags; +} + +/** + * ubifs_new_inode - allocate new UBIFS inode object. + * @c: UBIFS file-system description object + * @dir: parent inode + * @mode: inode mode flags + * + * This function finds an unused inode number, allocates new ubifs inode and + * initializes it. Returns new ubifs inode in case of success and an error code + * in case of failure. + */ +static struct ubifs_inode *ubifs_new_inode(struct ubifs_info *c, + const struct inode *dir, + unsigned int mode) +{ + int err; + time_t now = time(NULL); + struct ubifs_inode *ui; + struct inode *inode; + + ui = kzalloc(sizeof(struct ubifs_inode), GFP_KERNEL); + if (!ui) + return ERR_PTR(-ENOMEM); + + inode = &ui->vfs_inode; + inode->atime_sec = inode->ctime_sec = inode->mtime_sec = now; + inode->nlink = 1; + inode->mode = mode; + if (dir) { + /* Create non root dir. */ + inode->uid = dir->uid; + inode->gid = dir->gid; + if ((dir->mode & S_ISGID) && S_ISDIR(mode)) + inode->mode |= S_ISGID; + ui->flags = inherit_flags(c, dir, mode); + } + if (S_ISDIR(mode)) + ui->ui_size = UBIFS_INO_NODE_SZ; + if (S_ISREG(mode)) + ui->compr_type = c->default_compr; + else + ui->compr_type = UBIFS_COMPR_NONE; + + if (dir) { + spin_lock(&c->cnt_lock); + /* Inode number overflow is currently not supported */ + if (c->highest_inum >= INUM_WARN_WATERMARK) { + if (c->highest_inum >= INUM_WATERMARK) { + spin_unlock(&c->cnt_lock); + ubifs_err(c, "out of inode numbers"); + err = -EINVAL; + goto out; + } + ubifs_warn(c, "running out of inode numbers (current %lu, max %u)", + (unsigned long)c->highest_inum, INUM_WATERMARK); + } + inode->inum = ++c->highest_inum; + } else { + /* Create root dir. */ + inode->inum = UBIFS_ROOT_INO; + } + /* + * The creation sequence number remains with this inode for its + * lifetime. All nodes for this inode have a greater sequence number, + * and so it is possible to distinguish obsolete nodes belonging to a + * previous incarnation of the same inode number - for example, for the + * purpose of rebuilding the index. + */ + ui->creat_sqnum = ++c->max_sqnum; + spin_unlock(&c->cnt_lock); + + return ui; + +out: + kfree(ui); + return ERR_PTR(err); +} + +/** + * ubifs_lookup_by_inum - look up the UBIFS inode according to inode number. + * @c: UBIFS file-system description object + * @inum: inode number + * + * This function looks up the UBIFS inode according to a given inode number. + * Returns zero in case of success and an error code in case of failure. + */ +struct ubifs_inode *ubifs_lookup_by_inum(struct ubifs_info *c, ino_t inum) +{ + int err; + union ubifs_key key; + struct inode *inode; + struct ubifs_inode *ui; + struct ubifs_ino_node *ino = NULL; + + ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS); + if (!ino) + return ERR_PTR(-ENOMEM); + + ui = kzalloc(sizeof(struct ubifs_inode), GFP_KERNEL); + if (!ui) { + err = -ENOMEM; + goto out; + } + + inode = &ui->vfs_inode; + ino_key_init(c, &key, inum); + err = ubifs_tnc_lookup(c, &key, ino); + if (err) { + kfree(ui); + ubifs_assert(c, !get_failure_reason_callback(c)); + goto out; + } + + inode = &ui->vfs_inode; + inode->inum = inum; + inode->uid = le32_to_cpu(ino->uid); + inode->gid = le32_to_cpu(ino->gid); + inode->mode = le32_to_cpu(ino->mode); + inode->nlink = le32_to_cpu(ino->nlink); + inode->atime_sec = le64_to_cpu(ino->atime_sec); + inode->ctime_sec = le64_to_cpu(ino->ctime_sec); + inode->mtime_sec = le64_to_cpu(ino->mtime_sec); + inode->atime_nsec = le32_to_cpu(ino->atime_nsec); + inode->ctime_nsec = le32_to_cpu(ino->ctime_nsec); + inode->mtime_nsec = le32_to_cpu(ino->mtime_nsec); + ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum); + ui->xattr_size = le32_to_cpu(ino->xattr_size); + ui->xattr_cnt = le32_to_cpu(ino->xattr_cnt); + ui->xattr_names = le32_to_cpu(ino->xattr_names); + ui->compr_type = le16_to_cpu(ino->compr_type); + ui->ui_size = le64_to_cpu(ino->size); + ui->flags = le32_to_cpu(ino->flags); + ui->data_len = le32_to_cpu(ino->data_len); + +out: + kfree(ino); + return err ? ERR_PTR(err) : ui; +} + +struct ubifs_inode *ubifs_lookup(struct ubifs_info *c, + struct ubifs_inode *dir_ui, + const struct fscrypt_name *nm) +{ + int err; + ino_t inum; + union ubifs_key key; + struct ubifs_dent_node *dent; + + if (fname_len(nm) > UBIFS_MAX_NLEN) + return ERR_PTR(-ENAMETOOLONG); + + dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS); + if (!dent) + return ERR_PTR(-ENOMEM); + + dent_key_init(c, &key, dir_ui->vfs_inode.inum, nm); + err = ubifs_tnc_lookup_nm(c, &key, dent, nm); + if (err) { + kfree(dent); + ubifs_assert(c, !get_failure_reason_callback(c)); + return ERR_PTR(err); + } + inum = le64_to_cpu(dent->inum); + kfree(dent); + + return ubifs_lookup_by_inum(c, inum); +} + +int ubifs_mkdir(struct ubifs_info *c, struct ubifs_inode *dir_ui, + const struct fscrypt_name *nm, unsigned int mode) +{ + struct ubifs_inode *ui; + struct inode *inode, *dir = &dir_ui->vfs_inode; + int err, sz_change; + struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1, + .dirtied_ino = 1}; + /* + * Budget request settings: new inode, new direntry and changing parent + * directory inode. + */ + dbg_gen("dent '%s', mode %#hx in dir ino %lu", + fname_name(nm), mode, dir->inum); + + /* New dir is not allowed to be created under an encrypted directory. */ + ubifs_assert(c, !(dir_ui->flags & UBIFS_CRYPT_FL)); + + err = ubifs_budget_space(c, &req); + if (err) + return err; + + sz_change = CALC_DENT_SIZE(fname_len(nm)); + + ui = ubifs_new_inode(c, dir, S_IFDIR | mode); + if (IS_ERR(ui)) { + err = PTR_ERR(ui); + goto out_budg; + } + + inode = &ui->vfs_inode; + inode->nlink++; + dir->nlink++; + dir_ui->ui_size += sz_change; + dir->ctime_sec = dir->mtime_sec = inode->ctime_sec; + err = ubifs_jnl_update_file(c, dir_ui, nm, ui); + if (err) { + ubifs_err(c, "cannot create directory, error %d", err); + goto out_cancel; + } + + kfree(ui); + ubifs_release_budget(c, &req); + return 0; + +out_cancel: + dir_ui->ui_size -= sz_change; + dir->nlink--; + kfree(ui); +out_budg: + ubifs_release_budget(c, &req); + return err; +} + +/** + * ubifs_link_recovery - link a disconnected file into the target directory. + * @c: UBIFS file-system description object + * @dir_ui: target directory + * @ui: the UBIFS inode of disconnected file + * @nm: directory entry name + * + * This function links the inode of disconnected file to a directory entry name + * under the target directory. Returns zero in case of success and an error code + * in case of failure. + */ +int ubifs_link_recovery(struct ubifs_info *c, struct ubifs_inode *dir_ui, + struct ubifs_inode *ui, const struct fscrypt_name *nm) +{ + struct inode *inode = &ui->vfs_inode, *dir = &dir_ui->vfs_inode; + int err, sz_change; + struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2, + .dirtied_ino_d = ALIGN(ui->data_len, 8) }; + time_t now = time(NULL); + + /* + * Budget request settings: new direntry, changing the target inode, + * changing the parent inode. + */ + dbg_gen("dent '%s' to ino %lu (nlink %d) in dir ino %lu", + fname_name(nm), inode->inum, inode->nlink, dir->inum); + + /* New dir is not allowed to be created under an encrypted directory. */ + ubifs_assert(c, !(dir_ui->flags & UBIFS_CRYPT_FL)); + + sz_change = CALC_DENT_SIZE(fname_len(nm)); + + err = ubifs_budget_space(c, &req); + if (err) + return err; + + inode->ctime_sec = now; + dir_ui->ui_size += sz_change; + dir->ctime_sec = dir->mtime_sec = now; + err = ubifs_jnl_update_file(c, dir_ui, nm, ui); + if (err) + goto out_cancel; + + ubifs_release_budget(c, &req); + return 0; + +out_cancel: + dir_ui->ui_size -= sz_change; + ubifs_release_budget(c, &req); + return err; +} + +/** + * ubifs_create_root - create the root inode. + * @c: UBIFS file-system description object + * + * This function creates a new inode for the root directory. Returns zero in + * case of success and an error code in case of failure. + */ +int ubifs_create_root(struct ubifs_info *c) +{ + int err; + struct inode *inode; + struct ubifs_budget_req req = { .new_ino = 1 }; + struct ubifs_inode *ui; + + /* Budget request settings: new inode. */ + dbg_gen("create root dir"); + + err = ubifs_budget_space(c, &req); + if (err) + return err; + + ui = ubifs_new_inode(c, NULL, S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO); + if (IS_ERR(ui)) { + err = PTR_ERR(ui); + goto out_budg; + } + + inode = &ui->vfs_inode; + inode->nlink = 2; + ui->ui_size = UBIFS_INO_NODE_SZ; + ui->flags = UBIFS_COMPR_FL; + err = ubifs_jnl_update_file(c, NULL, NULL, ui); + if (err) + goto out_ui; + + kfree(ui); + ubifs_release_budget(c, &req); + return 0; + +out_ui: + kfree(ui); +out_budg: + ubifs_release_budget(c, &req); + ubifs_err(c, "cannot create root dir, error %d", err); + return err; +} diff --git a/ubifs-utils/libubifs/find.c b/ubifs-utils/libubifs/find.c new file mode 100644 index 0000000..364252e --- /dev/null +++ b/ubifs-utils/libubifs/find.c @@ -0,0 +1,970 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file contains functions for finding LEBs for various purposes e.g. + * garbage collection. In general, lprops category heaps and lists are used + * for fast access, falling back on scanning the LPT as a last resort. + */ + +#include <sys/types.h> + +#include "linux_err.h" +#include "bitops.h" +#include "sort.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "misc.h" + +/** + * struct scan_data - data provided to scan callback functions + * @min_space: minimum number of bytes for which to scan + * @pick_free: whether it is OK to scan for empty LEBs + * @lnum: LEB number found is returned here + * @exclude_index: whether to exclude index LEBs + */ +struct scan_data { + int min_space; + int pick_free; + int lnum; + int exclude_index; +}; + +/** + * valuable - determine whether LEB properties are valuable. + * @c: the UBIFS file-system description object + * @lprops: LEB properties + * + * This function return %1 if the LEB properties should be added to the LEB + * properties tree in memory. Otherwise %0 is returned. + */ +static int valuable(struct ubifs_info *c, const struct ubifs_lprops *lprops) +{ + int n, cat = lprops->flags & LPROPS_CAT_MASK; + struct ubifs_lpt_heap *heap; + + switch (cat) { + case LPROPS_DIRTY: + case LPROPS_DIRTY_IDX: + case LPROPS_FREE: + heap = &c->lpt_heap[cat - 1]; + if (heap->cnt < heap->max_cnt) + return 1; + if (lprops->free + lprops->dirty >= c->dark_wm) + return 1; + return 0; + case LPROPS_EMPTY: + n = c->lst.empty_lebs + c->freeable_cnt - + c->lst.taken_empty_lebs; + if (n < c->lsave_cnt) + return 1; + return 0; + case LPROPS_FREEABLE: + return 1; + case LPROPS_FRDI_IDX: + return 1; + } + return 0; +} + +/** + * scan_for_dirty_cb - dirty space scan callback. + * @c: the UBIFS file-system description object + * @lprops: LEB properties to scan + * @in_tree: whether the LEB properties are in main memory + * @arg: information passed to and from the caller of the scan + * + * This function returns a code that indicates whether the scan should continue + * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree + * in main memory (%LPT_SCAN_ADD), or whether the scan should stop + * (%LPT_SCAN_STOP). + */ +static int scan_for_dirty_cb(struct ubifs_info *c, + const struct ubifs_lprops *lprops, int in_tree, + void *arg) +{ + struct scan_data *data = arg; + int ret = LPT_SCAN_CONTINUE; + + /* Exclude LEBs that are currently in use */ + if (lprops->flags & LPROPS_TAKEN) + return LPT_SCAN_CONTINUE; + /* Determine whether to add these LEB properties to the tree */ + if (!in_tree && valuable(c, lprops)) + ret |= LPT_SCAN_ADD; + /* Exclude LEBs with too little space */ + if (lprops->free + lprops->dirty < data->min_space) + return ret; + /* If specified, exclude index LEBs */ + if (data->exclude_index && lprops->flags & LPROPS_INDEX) + return ret; + /* If specified, exclude empty or freeable LEBs */ + if (lprops->free + lprops->dirty == c->leb_size) { + if (!data->pick_free) + return ret; + /* Exclude LEBs with too little dirty space (unless it is empty) */ + } else if (lprops->dirty < c->dead_wm) + return ret; + /* Finally we found space */ + data->lnum = lprops->lnum; + return LPT_SCAN_ADD | LPT_SCAN_STOP; +} + +/** + * scan_for_dirty - find a data LEB with free space. + * @c: the UBIFS file-system description object + * @min_space: minimum amount free plus dirty space the returned LEB has to + * have + * @pick_free: if it is OK to return a free or freeable LEB + * @exclude_index: whether to exclude index LEBs + * + * This function returns a pointer to the LEB properties found or a negative + * error code. + */ +static const struct ubifs_lprops *scan_for_dirty(struct ubifs_info *c, + int min_space, int pick_free, + int exclude_index) +{ + const struct ubifs_lprops *lprops; + struct ubifs_lpt_heap *heap; + struct scan_data data; + int err, i; + + /* There may be an LEB with enough dirty space on the free heap */ + heap = &c->lpt_heap[LPROPS_FREE - 1]; + for (i = 0; i < heap->cnt; i++) { + lprops = heap->arr[i]; + if (lprops->free + lprops->dirty < min_space) + continue; + if (lprops->dirty < c->dead_wm) + continue; + return lprops; + } + /* + * A LEB may have fallen off of the bottom of the dirty heap, and ended + * up as uncategorized even though it has enough dirty space for us now, + * so check the uncategorized list. N.B. neither empty nor freeable LEBs + * can end up as uncategorized because they are kept on lists not + * finite-sized heaps. + */ + list_for_each_entry(lprops, &c->uncat_list, list) { + if (lprops->flags & LPROPS_TAKEN) + continue; + if (lprops->free + lprops->dirty < min_space) + continue; + if (exclude_index && (lprops->flags & LPROPS_INDEX)) + continue; + if (lprops->dirty < c->dead_wm) + continue; + return lprops; + } + /* We have looked everywhere in main memory, now scan the flash */ + if (c->pnodes_have >= c->pnode_cnt) + /* All pnodes are in memory, so skip scan */ + return ERR_PTR(-ENOSPC); + data.min_space = min_space; + data.pick_free = pick_free; + data.lnum = -1; + data.exclude_index = exclude_index; + err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum, scan_for_dirty_cb, + &data); + if (err) + return ERR_PTR(err); + ubifs_assert(c, data.lnum >= c->main_first && data.lnum < c->leb_cnt); + c->lscan_lnum = data.lnum; + lprops = ubifs_lpt_lookup_dirty(c, data.lnum); + if (IS_ERR(lprops)) + return lprops; + ubifs_assert(c, lprops->lnum == data.lnum); + ubifs_assert(c, lprops->free + lprops->dirty >= min_space); + ubifs_assert(c, lprops->dirty >= c->dead_wm || + (pick_free && + lprops->free + lprops->dirty == c->leb_size)); + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, !exclude_index || !(lprops->flags & LPROPS_INDEX)); + return lprops; +} + +/** + * ubifs_find_dirty_leb - find a dirty LEB for the Garbage Collector. + * @c: the UBIFS file-system description object + * @ret_lp: LEB properties are returned here on exit + * @min_space: minimum amount free plus dirty space the returned LEB has to + * have + * @pick_free: controls whether it is OK to pick empty or index LEBs + * + * This function tries to find a dirty logical eraseblock which has at least + * @min_space free and dirty space. It prefers to take an LEB from the dirty or + * dirty index heap, and it falls-back to LPT scanning if the heaps are empty + * or do not have an LEB which satisfies the @min_space criteria. + * + * Note, LEBs which have less than dead watermark of free + dirty space are + * never picked by this function. + * + * The additional @pick_free argument controls if this function has to return a + * free or freeable LEB if one is present. For example, GC must to set it to %1, + * when called from the journal space reservation function, because the + * appearance of free space may coincide with the loss of enough dirty space + * for GC to succeed anyway. + * + * In contrast, if the Garbage Collector is called from budgeting, it should + * just make free space, not return LEBs which are already free or freeable. + * + * In addition @pick_free is set to %2 by the recovery process in order to + * recover gc_lnum in which case an index LEB must not be returned. + * + * This function returns zero and the LEB properties of found dirty LEB in case + * of success, %-ENOSPC if no dirty LEB was found and a negative error code in + * case of other failures. The returned LEB is marked as "taken". + */ +int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp, + int min_space, int pick_free) +{ + int err = 0, sum, exclude_index = pick_free == 2 ? 1 : 0; + const struct ubifs_lprops *lp = NULL, *idx_lp = NULL; + struct ubifs_lpt_heap *heap, *idx_heap; + + ubifs_get_lprops(c); + + if (pick_free) { + int lebs, rsvd_idx_lebs = 0; + + spin_lock(&c->space_lock); + lebs = c->lst.empty_lebs + c->idx_gc_cnt; + lebs += c->freeable_cnt - c->lst.taken_empty_lebs; + + /* + * Note, the index may consume more LEBs than have been reserved + * for it. It is OK because it might be consolidated by GC. + * But if the index takes fewer LEBs than it is reserved for it, + * this function must avoid picking those reserved LEBs. + */ + if (c->bi.min_idx_lebs >= c->lst.idx_lebs) { + rsvd_idx_lebs = c->bi.min_idx_lebs - c->lst.idx_lebs; + exclude_index = 1; + } + spin_unlock(&c->space_lock); + + /* Check if there are enough free LEBs for the index */ + if (rsvd_idx_lebs < lebs) { + /* OK, try to find an empty LEB */ + lp = ubifs_fast_find_empty(c); + if (lp) + goto found; + + /* Or a freeable LEB */ + lp = ubifs_fast_find_freeable(c); + if (lp) + goto found; + } else + /* + * We cannot pick free/freeable LEBs in the below code. + */ + pick_free = 0; + } else { + spin_lock(&c->space_lock); + exclude_index = (c->bi.min_idx_lebs >= c->lst.idx_lebs); + spin_unlock(&c->space_lock); + } + + /* Look on the dirty and dirty index heaps */ + heap = &c->lpt_heap[LPROPS_DIRTY - 1]; + idx_heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1]; + + if (idx_heap->cnt && !exclude_index) { + idx_lp = idx_heap->arr[0]; + sum = idx_lp->free + idx_lp->dirty; + /* + * Since we reserve thrice as much space for the index than it + * actually takes, it does not make sense to pick indexing LEBs + * with less than, say, half LEB of dirty space. May be half is + * not the optimal boundary - this should be tested and + * checked. This boundary should determine how much we use + * in-the-gaps to consolidate the index comparing to how much + * we use garbage collector to consolidate it. The "half" + * criteria just feels to be fine. + */ + if (sum < min_space || sum < c->half_leb_size) + idx_lp = NULL; + } + + if (heap->cnt) { + lp = heap->arr[0]; + if (lp->dirty + lp->free < min_space) + lp = NULL; + } + + /* Pick the LEB with most space */ + if (idx_lp && lp) { + if (idx_lp->free + idx_lp->dirty >= lp->free + lp->dirty) + lp = idx_lp; + } else if (idx_lp && !lp) + lp = idx_lp; + + if (lp) { + ubifs_assert(c, lp->free + lp->dirty >= c->dead_wm); + goto found; + } + + /* Did not find a dirty LEB on the dirty heaps, have to scan */ + dbg_find("scanning LPT for a dirty LEB"); + lp = scan_for_dirty(c, min_space, pick_free, exclude_index); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + ubifs_assert(c, lp->dirty >= c->dead_wm || + (pick_free && lp->free + lp->dirty == c->leb_size)); + +found: + dbg_find("found LEB %d, free %d, dirty %d, flags %#x", + lp->lnum, lp->free, lp->dirty, lp->flags); + + lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC, + lp->flags | LPROPS_TAKEN, 0); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + memcpy(ret_lp, lp, sizeof(struct ubifs_lprops)); + +out: + ubifs_release_lprops(c); + return err; +} + +/** + * scan_for_free_cb - free space scan callback. + * @c: the UBIFS file-system description object + * @lprops: LEB properties to scan + * @in_tree: whether the LEB properties are in main memory + * @arg: information passed to and from the caller of the scan + * + * This function returns a code that indicates whether the scan should continue + * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree + * in main memory (%LPT_SCAN_ADD), or whether the scan should stop + * (%LPT_SCAN_STOP). + */ +static int scan_for_free_cb(struct ubifs_info *c, + const struct ubifs_lprops *lprops, int in_tree, + void *arg) +{ + struct scan_data *data = arg; + int ret = LPT_SCAN_CONTINUE; + + /* Exclude LEBs that are currently in use */ + if (lprops->flags & LPROPS_TAKEN) + return LPT_SCAN_CONTINUE; + /* Determine whether to add these LEB properties to the tree */ + if (!in_tree && valuable(c, lprops)) + ret |= LPT_SCAN_ADD; + /* Exclude index LEBs */ + if (lprops->flags & LPROPS_INDEX) + return ret; + /* Exclude LEBs with too little space */ + if (lprops->free < data->min_space) + return ret; + /* If specified, exclude empty LEBs */ + if (!data->pick_free && lprops->free == c->leb_size) + return ret; + /* + * LEBs that have only free and dirty space must not be allocated + * because they may have been unmapped already or they may have data + * that is obsolete only because of nodes that are still sitting in a + * wbuf. + */ + if (lprops->free + lprops->dirty == c->leb_size && lprops->dirty > 0) + return ret; + /* Finally we found space */ + data->lnum = lprops->lnum; + return LPT_SCAN_ADD | LPT_SCAN_STOP; +} + +/** + * do_find_free_space - find a data LEB with free space. + * @c: the UBIFS file-system description object + * @min_space: minimum amount of free space required + * @pick_free: whether it is OK to scan for empty LEBs + * @squeeze: whether to try to find space in a non-empty LEB first + * + * This function returns a pointer to the LEB properties found or a negative + * error code. + */ +static +const struct ubifs_lprops *do_find_free_space(struct ubifs_info *c, + int min_space, int pick_free, + int squeeze) +{ + const struct ubifs_lprops *lprops; + struct ubifs_lpt_heap *heap; + struct scan_data data; + int err, i; + + if (squeeze) { + lprops = ubifs_fast_find_free(c); + if (lprops && lprops->free >= min_space) + return lprops; + } + if (pick_free) { + lprops = ubifs_fast_find_empty(c); + if (lprops) + return lprops; + } + if (!squeeze) { + lprops = ubifs_fast_find_free(c); + if (lprops && lprops->free >= min_space) + return lprops; + } + /* There may be an LEB with enough free space on the dirty heap */ + heap = &c->lpt_heap[LPROPS_DIRTY - 1]; + for (i = 0; i < heap->cnt; i++) { + lprops = heap->arr[i]; + if (lprops->free >= min_space) + return lprops; + } + /* + * A LEB may have fallen off of the bottom of the free heap, and ended + * up as uncategorized even though it has enough free space for us now, + * so check the uncategorized list. N.B. neither empty nor freeable LEBs + * can end up as uncategorized because they are kept on lists not + * finite-sized heaps. + */ + list_for_each_entry(lprops, &c->uncat_list, list) { + if (lprops->flags & LPROPS_TAKEN) + continue; + if (lprops->flags & LPROPS_INDEX) + continue; + if (lprops->free >= min_space) + return lprops; + } + /* We have looked everywhere in main memory, now scan the flash */ + if (c->pnodes_have >= c->pnode_cnt) + /* All pnodes are in memory, so skip scan */ + return ERR_PTR(-ENOSPC); + data.min_space = min_space; + data.pick_free = pick_free; + data.lnum = -1; + err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum, + scan_for_free_cb, + &data); + if (err) + return ERR_PTR(err); + ubifs_assert(c, data.lnum >= c->main_first && data.lnum < c->leb_cnt); + c->lscan_lnum = data.lnum; + lprops = ubifs_lpt_lookup_dirty(c, data.lnum); + if (IS_ERR(lprops)) + return lprops; + ubifs_assert(c, lprops->lnum == data.lnum); + ubifs_assert(c, lprops->free >= min_space); + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, !(lprops->flags & LPROPS_INDEX)); + return lprops; +} + +/** + * ubifs_find_free_space - find a data LEB with free space. + * @c: the UBIFS file-system description object + * @min_space: minimum amount of required free space + * @offs: contains offset of where free space starts on exit + * @squeeze: whether to try to find space in a non-empty LEB first + * + * This function looks for an LEB with at least @min_space bytes of free space. + * It tries to find an empty LEB if possible. If no empty LEBs are available, + * this function searches for a non-empty data LEB. The returned LEB is marked + * as "taken". + * + * This function returns found LEB number in case of success, %-ENOSPC if it + * failed to find a LEB with @min_space bytes of free space and other a negative + * error codes in case of failure. + */ +int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *offs, + int squeeze) +{ + const struct ubifs_lprops *lprops; + int lebs, rsvd_idx_lebs, pick_free = 0, err, lnum, flags; + + dbg_find("min_space %d", min_space); + ubifs_get_lprops(c); + + /* Check if there are enough empty LEBs for commit */ + spin_lock(&c->space_lock); + if (c->bi.min_idx_lebs > c->lst.idx_lebs) + rsvd_idx_lebs = c->bi.min_idx_lebs - c->lst.idx_lebs; + else + rsvd_idx_lebs = 0; + lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt - + c->lst.taken_empty_lebs; + if (rsvd_idx_lebs < lebs) + /* + * OK to allocate an empty LEB, but we still don't want to go + * looking for one if there aren't any. + */ + if (c->lst.empty_lebs - c->lst.taken_empty_lebs > 0) { + pick_free = 1; + /* + * Because we release the space lock, we must account + * for this allocation here. After the LEB properties + * flags have been updated, we subtract one. Note, the + * result of this is that lprops also decreases + * @taken_empty_lebs in 'ubifs_change_lp()', so it is + * off by one for a short period of time which may + * introduce a small disturbance to budgeting + * calculations, but this is harmless because at the + * worst case this would make the budgeting subsystem + * be more pessimistic than needed. + * + * Fundamentally, this is about serialization of the + * budgeting and lprops subsystems. We could make the + * @space_lock a mutex and avoid dropping it before + * calling 'ubifs_change_lp()', but mutex is more + * heavy-weight, and we want budgeting to be as fast as + * possible. + */ + c->lst.taken_empty_lebs += 1; + } + spin_unlock(&c->space_lock); + + lprops = do_find_free_space(c, min_space, pick_free, squeeze); + if (IS_ERR(lprops)) { + err = PTR_ERR(lprops); + goto out; + } + + lnum = lprops->lnum; + flags = lprops->flags | LPROPS_TAKEN; + + lprops = ubifs_change_lp(c, lprops, LPROPS_NC, LPROPS_NC, flags, 0); + if (IS_ERR(lprops)) { + err = PTR_ERR(lprops); + goto out; + } + + if (pick_free) { + spin_lock(&c->space_lock); + c->lst.taken_empty_lebs -= 1; + spin_unlock(&c->space_lock); + } + + *offs = c->leb_size - lprops->free; + ubifs_release_lprops(c); + + if (*offs == 0) { + /* + * Ensure that empty LEBs have been unmapped. They may not have + * been, for example, because of an unclean unmount. Also + * LEBs that were freeable LEBs (free + dirty == leb_size) will + * not have been unmapped. + */ + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + + dbg_find("found LEB %d, free %d", lnum, c->leb_size - *offs); + ubifs_assert(c, *offs <= c->leb_size - min_space); + return lnum; + +out: + if (pick_free) { + spin_lock(&c->space_lock); + c->lst.taken_empty_lebs -= 1; + spin_unlock(&c->space_lock); + } + ubifs_release_lprops(c); + return err; +} + +/** + * scan_for_idx_cb - callback used by the scan for a free LEB for the index. + * @c: the UBIFS file-system description object + * @lprops: LEB properties to scan + * @in_tree: whether the LEB properties are in main memory + * @arg: information passed to and from the caller of the scan + * + * This function returns a code that indicates whether the scan should continue + * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree + * in main memory (%LPT_SCAN_ADD), or whether the scan should stop + * (%LPT_SCAN_STOP). + */ +static int scan_for_idx_cb(struct ubifs_info *c, + const struct ubifs_lprops *lprops, int in_tree, + void *arg) +{ + struct scan_data *data = arg; + int ret = LPT_SCAN_CONTINUE; + + /* Exclude LEBs that are currently in use */ + if (lprops->flags & LPROPS_TAKEN) + return LPT_SCAN_CONTINUE; + /* Determine whether to add these LEB properties to the tree */ + if (!in_tree && valuable(c, lprops)) + ret |= LPT_SCAN_ADD; + /* Exclude index LEBS */ + if (lprops->flags & LPROPS_INDEX) + return ret; + /* Exclude LEBs that cannot be made empty */ + if (lprops->free + lprops->dirty != c->leb_size) + return ret; + /* + * We are allocating for the index so it is safe to allocate LEBs with + * only free and dirty space, because write buffers are sync'd at commit + * start. + */ + data->lnum = lprops->lnum; + return LPT_SCAN_ADD | LPT_SCAN_STOP; +} + +/** + * scan_for_leb_for_idx - scan for a free LEB for the index. + * @c: the UBIFS file-system description object + */ +static const struct ubifs_lprops *scan_for_leb_for_idx(struct ubifs_info *c) +{ + const struct ubifs_lprops *lprops; + struct scan_data data; + int err; + + data.lnum = -1; + err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum, scan_for_idx_cb, + &data); + if (err) + return ERR_PTR(err); + ubifs_assert(c, data.lnum >= c->main_first && data.lnum < c->leb_cnt); + c->lscan_lnum = data.lnum; + lprops = ubifs_lpt_lookup_dirty(c, data.lnum); + if (IS_ERR(lprops)) + return lprops; + ubifs_assert(c, lprops->lnum == data.lnum); + ubifs_assert(c, lprops->free + lprops->dirty == c->leb_size); + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, !(lprops->flags & LPROPS_INDEX)); + return lprops; +} + +/** + * ubifs_find_free_leb_for_idx - find a free LEB for the index. + * @c: the UBIFS file-system description object + * + * This function looks for a free LEB and returns that LEB number. The returned + * LEB is marked as "taken", "index". + * + * Only empty LEBs are allocated. This is for two reasons. First, the commit + * calculates the number of LEBs to allocate based on the assumption that they + * will be empty. Secondly, free space at the end of an index LEB is not + * guaranteed to be empty because it may have been used by the in-the-gaps + * method prior to an unclean unmount. + * + * If no LEB is found %-ENOSPC is returned. For other failures another negative + * error code is returned. + */ +int ubifs_find_free_leb_for_idx(struct ubifs_info *c) +{ + const struct ubifs_lprops *lprops; + int lnum = -1, err, flags; + + ubifs_get_lprops(c); + + lprops = ubifs_fast_find_empty(c); + if (!lprops) { + lprops = ubifs_fast_find_freeable(c); + if (!lprops) { + /* + * The first condition means the following: go scan the + * LPT if there are uncategorized lprops, which means + * there may be freeable LEBs there (UBIFS does not + * store the information about freeable LEBs in the + * master node). + */ + if (c->in_a_category_cnt != c->main_lebs || + c->lst.empty_lebs - c->lst.taken_empty_lebs > 0) { + ubifs_assert(c, c->freeable_cnt == 0); + lprops = scan_for_leb_for_idx(c); + if (IS_ERR(lprops)) { + err = PTR_ERR(lprops); + goto out; + } + } + } + } + + if (!lprops) { + err = -ENOSPC; + goto out; + } + + lnum = lprops->lnum; + + dbg_find("found LEB %d, free %d, dirty %d, flags %#x", + lnum, lprops->free, lprops->dirty, lprops->flags); + + flags = lprops->flags | LPROPS_TAKEN | LPROPS_INDEX; + lprops = ubifs_change_lp(c, lprops, c->leb_size, 0, flags, 0); + if (IS_ERR(lprops)) { + err = PTR_ERR(lprops); + goto out; + } + + ubifs_release_lprops(c); + + /* + * Ensure that empty LEBs have been unmapped. They may not have been, + * for example, because of an unclean unmount. Also LEBs that were + * freeable LEBs (free + dirty == leb_size) will not have been unmapped. + */ + err = ubifs_leb_unmap(c, lnum); + if (err) { + ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0, + LPROPS_TAKEN | LPROPS_INDEX, 0); + return err; + } + + return lnum; + +out: + ubifs_release_lprops(c); + return err; +} + +static int cmp_dirty_idx(const void *a, const void *b) +{ + const struct ubifs_lprops *lpa = *(const struct ubifs_lprops **)a; + const struct ubifs_lprops *lpb = *(const struct ubifs_lprops **)b; + + return lpa->dirty + lpa->free - lpb->dirty - lpb->free; +} + +/** + * ubifs_save_dirty_idx_lnums - save an array of the most dirty index LEB nos. + * @c: the UBIFS file-system description object + * + * This function is called each commit to create an array of LEB numbers of + * dirty index LEBs sorted in order of dirty and free space. This is used by + * the in-the-gaps method of TNC commit. + */ +int ubifs_save_dirty_idx_lnums(struct ubifs_info *c) +{ + int i; + + ubifs_get_lprops(c); + /* Copy the LPROPS_DIRTY_IDX heap */ + c->dirty_idx.cnt = c->lpt_heap[LPROPS_DIRTY_IDX - 1].cnt; + memcpy(c->dirty_idx.arr, c->lpt_heap[LPROPS_DIRTY_IDX - 1].arr, + sizeof(void *) * c->dirty_idx.cnt); + /* Sort it so that the dirtiest is now at the end */ + sort(c->dirty_idx.arr, c->dirty_idx.cnt, sizeof(void *), + cmp_dirty_idx, NULL); + dbg_find("found %d dirty index LEBs", c->dirty_idx.cnt); + if (c->dirty_idx.cnt) + dbg_find("dirtiest index LEB is %d with dirty %d and free %d", + c->dirty_idx.arr[c->dirty_idx.cnt - 1]->lnum, + c->dirty_idx.arr[c->dirty_idx.cnt - 1]->dirty, + c->dirty_idx.arr[c->dirty_idx.cnt - 1]->free); + /* Replace the lprops pointers with LEB numbers */ + for (i = 0; i < c->dirty_idx.cnt; i++) + c->dirty_idx.arr[i] = (void *)(size_t)c->dirty_idx.arr[i]->lnum; + ubifs_release_lprops(c); + return 0; +} + +/** + * scan_dirty_idx_cb - callback used by the scan for a dirty index LEB. + * @c: the UBIFS file-system description object + * @lprops: LEB properties to scan + * @in_tree: whether the LEB properties are in main memory + * @arg: information passed to and from the caller of the scan + * + * This function returns a code that indicates whether the scan should continue + * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree + * in main memory (%LPT_SCAN_ADD), or whether the scan should stop + * (%LPT_SCAN_STOP). + */ +static int scan_dirty_idx_cb(struct ubifs_info *c, + const struct ubifs_lprops *lprops, int in_tree, + void *arg) +{ + struct scan_data *data = arg; + int ret = LPT_SCAN_CONTINUE; + + /* Exclude LEBs that are currently in use */ + if (lprops->flags & LPROPS_TAKEN) + return LPT_SCAN_CONTINUE; + /* Determine whether to add these LEB properties to the tree */ + if (!in_tree && valuable(c, lprops)) + ret |= LPT_SCAN_ADD; + /* Exclude non-index LEBs */ + if (!(lprops->flags & LPROPS_INDEX)) + return ret; + /* Exclude LEBs with too little space */ + if (lprops->free + lprops->dirty < c->min_idx_node_sz) + return ret; + /* Finally we found space */ + data->lnum = lprops->lnum; + return LPT_SCAN_ADD | LPT_SCAN_STOP; +} + +/** + * find_dirty_idx_leb - find a dirty index LEB. + * @c: the UBIFS file-system description object + * + * This function returns LEB number upon success and a negative error code upon + * failure. In particular, -ENOSPC is returned if a dirty index LEB is not + * found. + * + * Note that this function scans the entire LPT but it is called very rarely. + */ +static int find_dirty_idx_leb(struct ubifs_info *c) +{ + const struct ubifs_lprops *lprops; + struct ubifs_lpt_heap *heap; + struct scan_data data; + int err, i, ret; + + /* Check all structures in memory first */ + data.lnum = -1; + heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1]; + for (i = 0; i < heap->cnt; i++) { + lprops = heap->arr[i]; + ret = scan_dirty_idx_cb(c, lprops, 1, &data); + if (ret & LPT_SCAN_STOP) + goto found; + } + list_for_each_entry(lprops, &c->frdi_idx_list, list) { + ret = scan_dirty_idx_cb(c, lprops, 1, &data); + if (ret & LPT_SCAN_STOP) + goto found; + } + list_for_each_entry(lprops, &c->uncat_list, list) { + ret = scan_dirty_idx_cb(c, lprops, 1, &data); + if (ret & LPT_SCAN_STOP) + goto found; + } + if (c->pnodes_have >= c->pnode_cnt) + /* All pnodes are in memory, so skip scan */ + return -ENOSPC; + err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum, scan_dirty_idx_cb, + &data); + if (err) + return err; +found: + ubifs_assert(c, data.lnum >= c->main_first && data.lnum < c->leb_cnt); + c->lscan_lnum = data.lnum; + lprops = ubifs_lpt_lookup_dirty(c, data.lnum); + if (IS_ERR(lprops)) + return PTR_ERR(lprops); + ubifs_assert(c, lprops->lnum == data.lnum); + ubifs_assert(c, lprops->free + lprops->dirty >= c->min_idx_node_sz); + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, (lprops->flags & LPROPS_INDEX)); + + dbg_find("found dirty LEB %d, free %d, dirty %d, flags %#x", + lprops->lnum, lprops->free, lprops->dirty, lprops->flags); + + lprops = ubifs_change_lp(c, lprops, LPROPS_NC, LPROPS_NC, + lprops->flags | LPROPS_TAKEN, 0); + if (IS_ERR(lprops)) + return PTR_ERR(lprops); + + return lprops->lnum; +} + +/** + * get_idx_gc_leb - try to get a LEB number from trivial GC. + * @c: the UBIFS file-system description object + */ +static int get_idx_gc_leb(struct ubifs_info *c) +{ + const struct ubifs_lprops *lp; + int err, lnum; + + err = ubifs_get_idx_gc_leb(c); + if (err < 0) + return err; + lnum = err; + /* + * The LEB was due to be unmapped after the commit but + * it is needed now for this commit. + */ + lp = ubifs_lpt_lookup_dirty(c, lnum); + if (IS_ERR(lp)) + return PTR_ERR(lp); + lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC, + lp->flags | LPROPS_INDEX, -1); + if (IS_ERR(lp)) + return PTR_ERR(lp); + dbg_find("LEB %d, dirty %d and free %d flags %#x", + lp->lnum, lp->dirty, lp->free, lp->flags); + return lnum; +} + +/** + * find_dirtiest_idx_leb - find dirtiest index LEB from dirtiest array. + * @c: the UBIFS file-system description object + */ +static int find_dirtiest_idx_leb(struct ubifs_info *c) +{ + const struct ubifs_lprops *lp; + int lnum; + + while (1) { + if (!c->dirty_idx.cnt) + return -ENOSPC; + /* The lprops pointers were replaced by LEB numbers */ + lnum = (size_t)c->dirty_idx.arr[--c->dirty_idx.cnt]; + lp = ubifs_lpt_lookup(c, lnum); + if (IS_ERR(lp)) + return PTR_ERR(lp); + if ((lp->flags & LPROPS_TAKEN) || !(lp->flags & LPROPS_INDEX)) + continue; + lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC, + lp->flags | LPROPS_TAKEN, 0); + if (IS_ERR(lp)) + return PTR_ERR(lp); + break; + } + dbg_find("LEB %d, dirty %d and free %d flags %#x", lp->lnum, lp->dirty, + lp->free, lp->flags); + ubifs_assert(c, lp->flags & LPROPS_TAKEN); + ubifs_assert(c, lp->flags & LPROPS_INDEX); + return lnum; +} + +/** + * ubifs_find_dirty_idx_leb - try to find dirtiest index LEB as at last commit. + * @c: the UBIFS file-system description object + * + * This function attempts to find an untaken index LEB with the most free and + * dirty space that can be used without overwriting index nodes that were in the + * last index committed. + */ +int ubifs_find_dirty_idx_leb(struct ubifs_info *c) +{ + int err; + + ubifs_get_lprops(c); + + /* + * We made an array of the dirtiest index LEB numbers as at the start of + * last commit. Try that array first. + */ + err = find_dirtiest_idx_leb(c); + + /* Next try scanning the entire LPT */ + if (err == -ENOSPC) + err = find_dirty_idx_leb(c); + + /* Finally take any index LEBs awaiting trivial GC */ + if (err == -ENOSPC) + err = get_idx_gc_leb(c); + + ubifs_release_lprops(c); + return err; +} diff --git a/ubifs-utils/libubifs/gc.c b/ubifs-utils/libubifs/gc.c new file mode 100644 index 0000000..c359535 --- /dev/null +++ b/ubifs-utils/libubifs/gc.c @@ -0,0 +1,1021 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements garbage collection. The procedure for garbage collection + * is different depending on whether a LEB as an index LEB (contains index + * nodes) or not. For non-index LEBs, garbage collection finds a LEB which + * contains a lot of dirty space (obsolete nodes), and copies the non-obsolete + * nodes to the journal, at which point the garbage-collected LEB is free to be + * reused. For index LEBs, garbage collection marks the non-obsolete index nodes + * dirty in the TNC, and after the next commit, the garbage-collected LEB is + * to be reused. Garbage collection will cause the number of dirty index nodes + * to grow, however sufficient space is reserved for the index to ensure the + * commit will never run out of space. + * + * Notes about dead watermark. At current UBIFS implementation we assume that + * LEBs which have less than @c->dead_wm bytes of free + dirty space are full + * and not worth garbage-collecting. The dead watermark is one min. I/O unit + * size, or min. UBIFS node size, depending on what is greater. Indeed, UBIFS + * Garbage Collector has to synchronize the GC head's write buffer before + * returning, so this is about wasting one min. I/O unit. However, UBIFS GC can + * actually reclaim even very small pieces of dirty space by garbage collecting + * enough dirty LEBs, but we do not bother doing this at this implementation. + * + * Notes about dark watermark. The results of GC work depends on how big are + * the UBIFS nodes GC deals with. Large nodes make GC waste more space. Indeed, + * if GC move data from LEB A to LEB B and nodes in LEB A are large, GC would + * have to waste large pieces of free space at the end of LEB B, because nodes + * from LEB A would not fit. And the worst situation is when all nodes are of + * maximum size. So dark watermark is the amount of free + dirty space in LEB + * which are guaranteed to be reclaimable. If LEB has less space, the GC might + * be unable to reclaim it. So, LEBs with free + dirty greater than dark + * watermark are "good" LEBs from GC's point of view. The other LEBs are not so + * good, and GC takes extra care when moving them. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/* + * GC may need to move more than one LEB to make progress. The below constants + * define "soft" and "hard" limits on the number of LEBs the garbage collector + * may move. + */ +#define SOFT_LEBS_LIMIT 4 +#define HARD_LEBS_LIMIT 32 + +/** + * switch_gc_head - switch the garbage collection journal head. + * @c: UBIFS file-system description object + * + * This function switch the GC head to the next LEB which is reserved in + * @c->gc_lnum. Returns %0 in case of success, %-EAGAIN if commit is required, + * and other negative error code in case of failures. + */ +static int switch_gc_head(struct ubifs_info *c) +{ + int err, gc_lnum = c->gc_lnum; + struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf; + + ubifs_assert(c, gc_lnum != -1); + dbg_gc("switch GC head from LEB %d:%d to LEB %d (waste %d bytes)", + wbuf->lnum, wbuf->offs + wbuf->used, gc_lnum, + c->leb_size - wbuf->offs - wbuf->used); + + err = ubifs_wbuf_sync_nolock(wbuf); + if (err) + return err; + + /* + * The GC write-buffer was synchronized, we may safely unmap + * 'c->gc_lnum'. + */ + err = ubifs_leb_unmap(c, gc_lnum); + if (err) + return err; + + err = ubifs_add_bud_to_log(c, GCHD, gc_lnum, 0); + if (err) + return err; + + c->gc_lnum = -1; + err = ubifs_wbuf_seek_nolock(wbuf, gc_lnum, 0); + return err; +} + +/** + * data_nodes_cmp - compare 2 data nodes. + * @priv: UBIFS file-system description object + * @a: first data node + * @b: second data node + * + * This function compares data nodes @a and @b. Returns %1 if @a has greater + * inode or block number, and %-1 otherwise. + */ +static int data_nodes_cmp(void *priv, const struct list_head *a, + const struct list_head *b) +{ + ino_t inuma, inumb; + struct ubifs_info *c = priv; + struct ubifs_scan_node *sa, *sb; + + cond_resched(); + if (a == b) + return 0; + + sa = list_entry(a, struct ubifs_scan_node, list); + sb = list_entry(b, struct ubifs_scan_node, list); + + ubifs_assert(c, key_type(c, &sa->key) == UBIFS_DATA_KEY); + ubifs_assert(c, key_type(c, &sb->key) == UBIFS_DATA_KEY); + ubifs_assert(c, sa->type == UBIFS_DATA_NODE); + ubifs_assert(c, sb->type == UBIFS_DATA_NODE); + + inuma = key_inum(c, &sa->key); + inumb = key_inum(c, &sb->key); + + if (inuma == inumb) { + unsigned int blka = key_block(c, &sa->key); + unsigned int blkb = key_block(c, &sb->key); + + if (blka <= blkb) + return -1; + } else if (inuma <= inumb) + return -1; + + return 1; +} + +/* + * nondata_nodes_cmp - compare 2 non-data nodes. + * @priv: UBIFS file-system description object + * @a: first node + * @a: second node + * + * This function compares nodes @a and @b. It makes sure that inode nodes go + * first and sorted by length in descending order. Directory entry nodes go + * after inode nodes and are sorted in ascending hash valuer order. + */ +static int nondata_nodes_cmp(void *priv, const struct list_head *a, + const struct list_head *b) +{ + ino_t inuma, inumb; + struct ubifs_info *c = priv; + struct ubifs_scan_node *sa, *sb; + + cond_resched(); + if (a == b) + return 0; + + sa = list_entry(a, struct ubifs_scan_node, list); + sb = list_entry(b, struct ubifs_scan_node, list); + + ubifs_assert(c, key_type(c, &sa->key) != UBIFS_DATA_KEY && + key_type(c, &sb->key) != UBIFS_DATA_KEY); + ubifs_assert(c, sa->type != UBIFS_DATA_NODE && + sb->type != UBIFS_DATA_NODE); + + /* Inodes go before directory entries */ + if (sa->type == UBIFS_INO_NODE) { + if (sb->type == UBIFS_INO_NODE) + return sb->len - sa->len; + return -1; + } + if (sb->type == UBIFS_INO_NODE) + return 1; + + ubifs_assert(c, key_type(c, &sa->key) == UBIFS_DENT_KEY || + key_type(c, &sa->key) == UBIFS_XENT_KEY); + ubifs_assert(c, key_type(c, &sb->key) == UBIFS_DENT_KEY || + key_type(c, &sb->key) == UBIFS_XENT_KEY); + ubifs_assert(c, sa->type == UBIFS_DENT_NODE || + sa->type == UBIFS_XENT_NODE); + ubifs_assert(c, sb->type == UBIFS_DENT_NODE || + sb->type == UBIFS_XENT_NODE); + + inuma = key_inum(c, &sa->key); + inumb = key_inum(c, &sb->key); + + if (inuma == inumb) { + uint32_t hasha = key_hash(c, &sa->key); + uint32_t hashb = key_hash(c, &sb->key); + + if (hasha <= hashb) + return -1; + } else if (inuma <= inumb) + return -1; + + return 1; +} + +/** + * sort_nodes - sort nodes for GC. + * @c: UBIFS file-system description object + * @sleb: describes nodes to sort and contains the result on exit + * @nondata: contains non-data nodes on exit + * @min: minimum node size is returned here + * + * This function sorts the list of inodes to garbage collect. First of all, it + * kills obsolete nodes and separates data and non-data nodes to the + * @sleb->nodes and @nondata lists correspondingly. + * + * Data nodes are then sorted in block number order - this is important for + * bulk-read; data nodes with lower inode number go before data nodes with + * higher inode number, and data nodes with lower block number go before data + * nodes with higher block number; + * + * Non-data nodes are sorted as follows. + * o First go inode nodes - they are sorted in descending length order. + * o Then go directory entry nodes - they are sorted in hash order, which + * should supposedly optimize 'readdir()'. Direntry nodes with lower parent + * inode number go before direntry nodes with higher parent inode number, + * and direntry nodes with lower name hash values go before direntry nodes + * with higher name hash values. + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int sort_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb, + struct list_head *nondata, int *min) +{ + int err; + struct ubifs_scan_node *snod, *tmp; + + *min = INT_MAX; + + /* Separate data nodes and non-data nodes */ + list_for_each_entry_safe(snod, tmp, &sleb->nodes, list) { + ubifs_assert(c, snod->type == UBIFS_INO_NODE || + snod->type == UBIFS_DATA_NODE || + snod->type == UBIFS_DENT_NODE || + snod->type == UBIFS_XENT_NODE || + snod->type == UBIFS_TRUN_NODE || + snod->type == UBIFS_AUTH_NODE); + + if (snod->type != UBIFS_INO_NODE && + snod->type != UBIFS_DATA_NODE && + snod->type != UBIFS_DENT_NODE && + snod->type != UBIFS_XENT_NODE) { + /* Probably truncation node, zap it */ + list_del(&snod->list); + kfree(snod); + continue; + } + + ubifs_assert(c, key_type(c, &snod->key) == UBIFS_DATA_KEY || + key_type(c, &snod->key) == UBIFS_INO_KEY || + key_type(c, &snod->key) == UBIFS_DENT_KEY || + key_type(c, &snod->key) == UBIFS_XENT_KEY); + + err = ubifs_tnc_has_node(c, &snod->key, 0, sleb->lnum, + snod->offs, 0); + if (err < 0) + return err; + + if (!err) { + /* The node is obsolete, remove it from the list */ + list_del(&snod->list); + kfree(snod); + continue; + } + + if (snod->len < *min) + *min = snod->len; + + if (key_type(c, &snod->key) != UBIFS_DATA_KEY) + list_move_tail(&snod->list, nondata); + } + + /* Sort data and non-data nodes */ + list_sort(c, &sleb->nodes, &data_nodes_cmp); + list_sort(c, nondata, &nondata_nodes_cmp); + + err = dbg_check_data_nodes_order(c, &sleb->nodes); + if (err) + return err; + err = dbg_check_nondata_nodes_order(c, nondata); + if (err) + return err; + return 0; +} + +/** + * move_node - move a node. + * @c: UBIFS file-system description object + * @sleb: describes the LEB to move nodes from + * @snod: the mode to move + * @wbuf: write-buffer to move node to + * + * This function moves node @snod to @wbuf, changes TNC correspondingly, and + * destroys @snod. Returns zero in case of success and a negative error code in + * case of failure. + */ +static int move_node(struct ubifs_info *c, struct ubifs_scan_leb *sleb, + struct ubifs_scan_node *snod, struct ubifs_wbuf *wbuf) +{ + int err, new_lnum = wbuf->lnum, new_offs = wbuf->offs + wbuf->used; + + cond_resched(); + err = ubifs_wbuf_write_nolock(wbuf, snod->node, snod->len); + if (err) + return err; + + err = ubifs_tnc_replace(c, &snod->key, sleb->lnum, + snod->offs, new_lnum, new_offs, + snod->len); + list_del(&snod->list); + kfree(snod); + return err; +} + +/** + * move_nodes - move nodes. + * @c: UBIFS file-system description object + * @sleb: describes the LEB to move nodes from + * + * This function moves valid nodes from data LEB described by @sleb to the GC + * journal head. This function returns zero in case of success, %-EAGAIN if + * commit is required, and other negative error codes in case of other + * failures. + */ +static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb) +{ + int err, min; + LIST_HEAD(nondata); + struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf; + + if (wbuf->lnum == -1) { + /* + * The GC journal head is not set, because it is the first GC + * invocation since mount. + */ + err = switch_gc_head(c); + if (err) + return err; + } + + err = sort_nodes(c, sleb, &nondata, &min); + if (err) + goto out; + + /* Write nodes to their new location. Use the first-fit strategy */ + while (1) { + int avail, moved = 0; + struct ubifs_scan_node *snod, *tmp; + + /* Move data nodes */ + list_for_each_entry_safe(snod, tmp, &sleb->nodes, list) { + avail = c->leb_size - wbuf->offs - wbuf->used - + ubifs_auth_node_sz(c); + if (snod->len > avail) + /* + * Do not skip data nodes in order to optimize + * bulk-read. + */ + break; + + err = ubifs_shash_update(c, c->jheads[GCHD].log_hash, + snod->node, snod->len); + if (err) + goto out; + + err = move_node(c, sleb, snod, wbuf); + if (err) + goto out; + moved = 1; + } + + /* Move non-data nodes */ + list_for_each_entry_safe(snod, tmp, &nondata, list) { + avail = c->leb_size - wbuf->offs - wbuf->used - + ubifs_auth_node_sz(c); + if (avail < min) + break; + + if (snod->len > avail) { + /* + * Keep going only if this is an inode with + * some data. Otherwise stop and switch the GC + * head. IOW, we assume that data-less inode + * nodes and direntry nodes are roughly of the + * same size. + */ + if (key_type(c, &snod->key) == UBIFS_DENT_KEY || + snod->len == UBIFS_INO_NODE_SZ) + break; + continue; + } + + err = ubifs_shash_update(c, c->jheads[GCHD].log_hash, + snod->node, snod->len); + if (err) + goto out; + + err = move_node(c, sleb, snod, wbuf); + if (err) + goto out; + moved = 1; + } + + if (ubifs_authenticated(c) && moved) { + struct ubifs_auth_node *auth; + + auth = kmalloc(ubifs_auth_node_sz(c), GFP_NOFS); + if (!auth) { + err = -ENOMEM; + goto out; + } + + err = ubifs_prepare_auth_node(c, auth, + c->jheads[GCHD].log_hash); + if (err) { + kfree(auth); + goto out; + } + + err = ubifs_wbuf_write_nolock(wbuf, auth, + ubifs_auth_node_sz(c)); + if (err) { + kfree(auth); + goto out; + } + + ubifs_add_dirt(c, wbuf->lnum, ubifs_auth_node_sz(c)); + } + + if (list_empty(&sleb->nodes) && list_empty(&nondata)) + break; + + /* + * Waste the rest of the space in the LEB and switch to the + * next LEB. + */ + err = switch_gc_head(c); + if (err) + goto out; + } + + return 0; + +out: + list_splice_tail(&nondata, &sleb->nodes); + return err; +} + +/** + * gc_sync_wbufs - sync write-buffers for GC. + * @c: UBIFS file-system description object + * + * We must guarantee that obsoleting nodes are on flash. Unfortunately they may + * be in a write-buffer instead. That is, a node could be written to a + * write-buffer, obsoleting another node in a LEB that is GC'd. If that LEB is + * erased before the write-buffer is sync'd and then there is an unclean + * unmount, then an existing node is lost. To avoid this, we sync all + * write-buffers. + * + * This function returns %0 on success or a negative error code on failure. + */ +static int gc_sync_wbufs(struct ubifs_info *c) +{ + int err, i; + + for (i = 0; i < c->jhead_cnt; i++) { + if (i == GCHD) + continue; + err = ubifs_wbuf_sync(&c->jheads[i].wbuf); + if (err) + return err; + } + return 0; +} + +/** + * ubifs_garbage_collect_leb - garbage-collect a logical eraseblock. + * @c: UBIFS file-system description object + * @lp: describes the LEB to garbage collect + * + * This function garbage-collects an LEB and returns one of the @LEB_FREED, + * @LEB_RETAINED, etc positive codes in case of success, %-EAGAIN if commit is + * required, and other negative error codes in case of failures. + */ +int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf; + int err = 0, lnum = lp->lnum; + + ubifs_assert(c, c->gc_lnum != -1 || wbuf->offs + wbuf->used == 0 || + c->need_recovery); + ubifs_assert(c, c->gc_lnum != lnum); + ubifs_assert(c, wbuf->lnum != lnum); + + if (lp->free + lp->dirty == c->leb_size) { + /* Special case - a free LEB */ + dbg_gc("LEB %d is free, return it", lp->lnum); + ubifs_assert(c, !(lp->flags & LPROPS_INDEX)); + + if (lp->free != c->leb_size) { + /* + * Write buffers must be sync'd before unmapping + * freeable LEBs, because one of them may contain data + * which obsoletes something in 'lp->lnum'. + */ + err = gc_sync_wbufs(c); + if (err) + return err; + err = ubifs_change_one_lp(c, lp->lnum, c->leb_size, + 0, 0, 0, 0); + if (err) + return err; + } + err = ubifs_leb_unmap(c, lp->lnum); + if (err) + return err; + + if (c->gc_lnum == -1) { + c->gc_lnum = lnum; + return LEB_RETAINED; + } + + return LEB_FREED; + } + + /* + * We scan the entire LEB even though we only really need to scan up to + * (c->leb_size - lp->free). + */ + sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + + ubifs_assert(c, !list_empty(&sleb->nodes)); + snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list); + + if (snod->type == UBIFS_IDX_NODE) { + struct ubifs_gced_idx_leb *idx_gc; + + dbg_gc("indexing LEB %d (free %d, dirty %d)", + lnum, lp->free, lp->dirty); + list_for_each_entry(snod, &sleb->nodes, list) { + struct ubifs_idx_node *idx = snod->node; + int level = le16_to_cpu(idx->level); + + ubifs_assert(c, snod->type == UBIFS_IDX_NODE); + key_read(c, ubifs_idx_key(c, idx), &snod->key); + err = ubifs_dirty_idx_node(c, &snod->key, level, lnum, + snod->offs); + if (err) + goto out; + } + + idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS); + if (!idx_gc) { + err = -ENOMEM; + goto out; + } + + idx_gc->lnum = lnum; + idx_gc->unmap = 0; + list_add(&idx_gc->list, &c->idx_gc); + + /* + * Don't release the LEB until after the next commit, because + * it may contain data which is needed for recovery. So + * although we freed this LEB, it will become usable only after + * the commit. + */ + err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0, + LPROPS_INDEX, 1); + if (err) + goto out; + err = LEB_FREED_IDX; + } else { + dbg_gc("data LEB %d (free %d, dirty %d)", + lnum, lp->free, lp->dirty); + + err = move_nodes(c, sleb); + if (err) + goto out_inc_seq; + + err = gc_sync_wbufs(c); + if (err) + goto out_inc_seq; + + err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0, 0, 0); + if (err) + goto out_inc_seq; + + /* Allow for races with TNC */ + c->gced_lnum = lnum; + smp_wmb(); + c->gc_seq += 1; + smp_wmb(); + + if (c->gc_lnum == -1) { + c->gc_lnum = lnum; + err = LEB_RETAINED; + } else { + err = ubifs_wbuf_sync_nolock(wbuf); + if (err) + goto out; + + err = ubifs_leb_unmap(c, lnum); + if (err) + goto out; + + err = LEB_FREED; + } + } + +out: + ubifs_scan_destroy(sleb); + return err; + +out_inc_seq: + /* We may have moved at least some nodes so allow for races with TNC */ + c->gced_lnum = lnum; + smp_wmb(); + c->gc_seq += 1; + smp_wmb(); + goto out; +} + +/** + * ubifs_garbage_collect - UBIFS garbage collector. + * @c: UBIFS file-system description object + * @anyway: do GC even if there are free LEBs + * + * This function does out-of-place garbage collection. The return codes are: + * o positive LEB number if the LEB has been freed and may be used; + * o %-EAGAIN if the caller has to run commit; + * o %-ENOSPC if GC failed to make any progress; + * o other negative error codes in case of other errors. + * + * Garbage collector writes data to the journal when GC'ing data LEBs, and just + * marking indexing nodes dirty when GC'ing indexing LEBs. Thus, at some point + * commit may be required. But commit cannot be run from inside GC, because the + * caller might be holding the commit lock, so %-EAGAIN is returned instead; + * And this error code means that the caller has to run commit, and re-run GC + * if there is still no free space. + * + * There are many reasons why this function may return %-EAGAIN: + * o the log is full and there is no space to write an LEB reference for + * @c->gc_lnum; + * o the journal is too large and exceeds size limitations; + * o GC moved indexing LEBs, but they can be used only after the commit; + * o the shrinker fails to find clean znodes to free and requests the commit; + * o etc. + * + * Note, if the file-system is close to be full, this function may return + * %-EAGAIN infinitely, so the caller has to limit amount of re-invocations of + * the function. E.g., this happens if the limits on the journal size are too + * tough and GC writes too much to the journal before an LEB is freed. This + * might also mean that the journal is too large, and the TNC becomes to big, + * so that the shrinker is constantly called, finds not clean znodes to free, + * and requests commit. Well, this may also happen if the journal is all right, + * but another kernel process consumes too much memory. Anyway, infinite + * %-EAGAIN may happen, but in some extreme/misconfiguration cases. + */ +int ubifs_garbage_collect(struct ubifs_info *c, int anyway) +{ + int i, err, ret, min_space = c->dead_wm; + struct ubifs_lprops lp; + struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf; + + ubifs_assert_cmt_locked(c); + ubifs_assert(c, !c->ro_media && !c->ro_mount); + + if (ubifs_gc_should_commit(c)) + return -EAGAIN; + + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + + if (c->ro_error) { + ret = -EROFS; + goto out_unlock; + } + + /* We expect the write-buffer to be empty on entry */ + ubifs_assert(c, !wbuf->used); + + for (i = 0; ; i++) { + int space_before, space_after; + + /* Maybe continue after find and break before find */ + lp.lnum = -1; + + cond_resched(); + + /* Give the commit an opportunity to run */ + if (ubifs_gc_should_commit(c)) { + ret = -EAGAIN; + break; + } + + if (i > SOFT_LEBS_LIMIT && !list_empty(&c->idx_gc)) { + /* + * We've done enough iterations. Indexing LEBs were + * moved and will be available after the commit. + */ + dbg_gc("soft limit, some index LEBs GC'ed, -EAGAIN"); + ubifs_commit_required(c); + ret = -EAGAIN; + break; + } + + if (i > HARD_LEBS_LIMIT) { + /* + * We've moved too many LEBs and have not made + * progress, give up. + */ + dbg_gc("hard limit, -ENOSPC"); + ret = -ENOSPC; + break; + } + + /* + * Empty and freeable LEBs can turn up while we waited for + * the wbuf lock, or while we have been running GC. In that + * case, we should just return one of those instead of + * continuing to GC dirty LEBs. Hence we request + * 'ubifs_find_dirty_leb()' to return an empty LEB if it can. + */ + ret = ubifs_find_dirty_leb(c, &lp, min_space, anyway ? 0 : 1); + if (ret) { + if (ret == -ENOSPC) + dbg_gc("no more dirty LEBs"); + break; + } + + dbg_gc("found LEB %d: free %d, dirty %d, sum %d (min. space %d)", + lp.lnum, lp.free, lp.dirty, lp.free + lp.dirty, + min_space); + + space_before = c->leb_size - wbuf->offs - wbuf->used; + if (wbuf->lnum == -1) + space_before = 0; + + ret = ubifs_garbage_collect_leb(c, &lp); + if (ret < 0) { + if (ret == -EAGAIN) { + /* + * This is not error, so we have to return the + * LEB to lprops. But if 'ubifs_return_leb()' + * fails, its failure code is propagated to the + * caller instead of the original '-EAGAIN'. + */ + err = ubifs_return_leb(c, lp.lnum); + if (err) { + ret = err; + /* + * An LEB may always be "taken", + * so setting ubifs to read-only, + * and then executing sync wbuf will + * return -EROFS and enter the "out" + * error branch. + */ + ubifs_ro_mode(c, ret); + } + /* Maybe double return LEB if goto out */ + lp.lnum = -1; + break; + } + goto out; + } + + if (ret == LEB_FREED) { + /* An LEB has been freed and is ready for use */ + dbg_gc("LEB %d freed, return", lp.lnum); + ret = lp.lnum; + break; + } + + if (ret == LEB_FREED_IDX) { + /* + * This was an indexing LEB and it cannot be + * immediately used. And instead of requesting the + * commit straight away, we try to garbage collect some + * more. + */ + dbg_gc("indexing LEB %d freed, continue", lp.lnum); + continue; + } + + ubifs_assert(c, ret == LEB_RETAINED); + space_after = c->leb_size - wbuf->offs - wbuf->used; + dbg_gc("LEB %d retained, freed %d bytes", lp.lnum, + space_after - space_before); + + if (space_after > space_before) { + /* GC makes progress, keep working */ + min_space >>= 1; + if (min_space < c->dead_wm) + min_space = c->dead_wm; + continue; + } + + dbg_gc("did not make progress"); + + /* + * GC moved an LEB bud have not done any progress. This means + * that the previous GC head LEB contained too few free space + * and the LEB which was GC'ed contained only large nodes which + * did not fit that space. + * + * We can do 2 things: + * 1. pick another LEB in a hope it'll contain a small node + * which will fit the space we have at the end of current GC + * head LEB, but there is no guarantee, so we try this out + * unless we have already been working for too long; + * 2. request an LEB with more dirty space, which will force + * 'ubifs_find_dirty_leb()' to start scanning the lprops + * table, instead of just picking one from the heap + * (previously it already picked the dirtiest LEB). + */ + if (i < SOFT_LEBS_LIMIT) { + dbg_gc("try again"); + continue; + } + + min_space <<= 1; + if (min_space > c->dark_wm) + min_space = c->dark_wm; + dbg_gc("set min. space to %d", min_space); + } + + if (ret == -ENOSPC && !list_empty(&c->idx_gc)) { + dbg_gc("no space, some index LEBs GC'ed, -EAGAIN"); + ubifs_commit_required(c); + ret = -EAGAIN; + } + + err = ubifs_wbuf_sync_nolock(wbuf); + if (!err) + err = ubifs_leb_unmap(c, c->gc_lnum); + if (err) { + ret = err; + goto out; + } +out_unlock: + mutex_unlock(&wbuf->io_mutex); + return ret; + +out: + ubifs_assert(c, ret < 0); + ubifs_assert(c, ret != -ENOSPC && ret != -EAGAIN); + ubifs_wbuf_sync_nolock(wbuf); + ubifs_ro_mode(c, ret); + mutex_unlock(&wbuf->io_mutex); + if (lp.lnum != -1) + ubifs_return_leb(c, lp.lnum); + return ret; +} + +/** + * ubifs_gc_start_commit - garbage collection at start of commit. + * @c: UBIFS file-system description object + * + * If a LEB has only dirty and free space, then we may safely unmap it and make + * it free. Note, we cannot do this with indexing LEBs because dirty space may + * correspond index nodes that are required for recovery. In that case, the + * LEB cannot be unmapped until after the next commit. + * + * This function returns %0 upon success and a negative error code upon failure. + */ +int ubifs_gc_start_commit(struct ubifs_info *c) +{ + struct ubifs_gced_idx_leb *idx_gc; + const struct ubifs_lprops *lp; + int err = 0, flags; + + ubifs_get_lprops(c); + + /* + * Unmap (non-index) freeable LEBs. Note that recovery requires that all + * wbufs are sync'd before this, which is done in 'do_commit()'. + */ + while (1) { + lp = ubifs_fast_find_freeable(c); + if (!lp) + break; + ubifs_assert(c, !(lp->flags & LPROPS_TAKEN)); + ubifs_assert(c, !(lp->flags & LPROPS_INDEX)); + err = ubifs_leb_unmap(c, lp->lnum); + if (err) + goto out; + lp = ubifs_change_lp(c, lp, c->leb_size, 0, lp->flags, 0); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + ubifs_assert(c, !(lp->flags & LPROPS_TAKEN)); + ubifs_assert(c, !(lp->flags & LPROPS_INDEX)); + } + + /* Mark GC'd index LEBs OK to unmap after this commit finishes */ + list_for_each_entry(idx_gc, &c->idx_gc, list) + idx_gc->unmap = 1; + + /* Record index freeable LEBs for unmapping after commit */ + while (1) { + lp = ubifs_fast_find_frdi_idx(c); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + if (!lp) + break; + idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS); + if (!idx_gc) { + err = -ENOMEM; + goto out; + } + ubifs_assert(c, !(lp->flags & LPROPS_TAKEN)); + ubifs_assert(c, lp->flags & LPROPS_INDEX); + /* Don't release the LEB until after the next commit */ + flags = (lp->flags | LPROPS_TAKEN) ^ LPROPS_INDEX; + lp = ubifs_change_lp(c, lp, c->leb_size, 0, flags, 1); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + kfree(idx_gc); + goto out; + } + ubifs_assert(c, lp->flags & LPROPS_TAKEN); + ubifs_assert(c, !(lp->flags & LPROPS_INDEX)); + idx_gc->lnum = lp->lnum; + idx_gc->unmap = 1; + list_add(&idx_gc->list, &c->idx_gc); + } +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_gc_end_commit - garbage collection at end of commit. + * @c: UBIFS file-system description object + * + * This function completes out-of-place garbage collection of index LEBs. + */ +int ubifs_gc_end_commit(struct ubifs_info *c) +{ + struct ubifs_gced_idx_leb *idx_gc, *tmp; + struct ubifs_wbuf *wbuf; + int err = 0; + + wbuf = &c->jheads[GCHD].wbuf; + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + list_for_each_entry_safe(idx_gc, tmp, &c->idx_gc, list) + if (idx_gc->unmap) { + dbg_gc("LEB %d", idx_gc->lnum); + err = ubifs_leb_unmap(c, idx_gc->lnum); + if (err) + goto out; + err = ubifs_change_one_lp(c, idx_gc->lnum, LPROPS_NC, + LPROPS_NC, 0, LPROPS_TAKEN, -1); + if (err) + goto out; + list_del(&idx_gc->list); + kfree(idx_gc); + } +out: + mutex_unlock(&wbuf->io_mutex); + return err; +} + +/** + * ubifs_destroy_idx_gc - destroy idx_gc list. + * @c: UBIFS file-system description object + * + * This function destroys the @c->idx_gc list. It is called when unmounting + * so locks are not needed. Returns zero in case of success and a negative + * error code in case of failure. + */ +void ubifs_destroy_idx_gc(struct ubifs_info *c) +{ + while (!list_empty(&c->idx_gc)) { + struct ubifs_gced_idx_leb *idx_gc; + + idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb, + list); + c->idx_gc_cnt -= 1; + list_del(&idx_gc->list); + kfree(idx_gc); + } +} + +/** + * ubifs_get_idx_gc_leb - get a LEB from GC'd index LEB list. + * @c: UBIFS file-system description object + * + * Called during start commit so locks are not needed. + */ +int ubifs_get_idx_gc_leb(struct ubifs_info *c) +{ + struct ubifs_gced_idx_leb *idx_gc; + int lnum; + + if (list_empty(&c->idx_gc)) + return -ENOSPC; + idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb, list); + lnum = idx_gc->lnum; + /* c->idx_gc_cnt is updated by the caller when lprops are updated */ + list_del(&idx_gc->list); + kfree(idx_gc); + return lnum; +} diff --git a/ubifs-utils/libubifs/io.c b/ubifs-utils/libubifs/io.c new file mode 100644 index 0000000..b6fb331 --- /dev/null +++ b/ubifs-utils/libubifs/io.c @@ -0,0 +1,1088 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * Copyright (C) 2006, 2007 University of Szeged, Hungary + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + * Zoltan Sogor + */ + +/* + * This file implements UBIFS I/O subsystem which provides various I/O-related + * helper functions (reading/writing/checking/validating nodes) and implements + * write-buffering support. Write buffers help to save space which otherwise + * would have been wasted for padding to the nearest minimal I/O unit boundary. + * Instead, data first goes to the write-buffer and is flushed when the + * buffer is full or when it is not used for some time (by timer). This is + * similar to the mechanism is used by JFFS2. + * + * UBIFS distinguishes between minimum write size (@c->min_io_size) and maximum + * write size (@c->max_write_size). The latter is the maximum amount of bytes + * the underlying flash is able to program at a time, and writing in + * @c->max_write_size units should presumably be faster. Obviously, + * @c->min_io_size <= @c->max_write_size. Write-buffers are of + * @c->max_write_size bytes in size for maximum performance. However, when a + * write-buffer is flushed, only the portion of it (aligned to @c->min_io_size + * boundary) which contains data is written, not the whole write-buffer, + * because this is more space-efficient. + * + * This optimization adds few complications to the code. Indeed, on the one + * hand, we want to write in optimal @c->max_write_size bytes chunks, which + * also means aligning writes at the @c->max_write_size bytes offsets. On the + * other hand, we do not want to waste space when synchronizing the write + * buffer, so during synchronization we writes in smaller chunks. And this makes + * the next write offset to be not aligned to @c->max_write_size bytes. So the + * have to make sure that the write-buffer offset (@wbuf->offs) becomes aligned + * to @c->max_write_size bytes again. We do this by temporarily shrinking + * write-buffer size (@wbuf->size). + * + * Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by + * mutexes defined inside these objects. Since sometimes upper-level code + * has to lock the write-buffer (e.g. journal space reservation code), many + * functions related to write-buffers have "nolock" suffix which means that the + * caller has to lock the write-buffer before calling this function. + * + * UBIFS stores nodes at 64 bit-aligned addresses. If the node length is not + * aligned, UBIFS starts the next node from the aligned address, and the padded + * bytes may contain any rubbish. In other words, UBIFS does not put padding + * bytes in those small gaps. Common headers of nodes store real node lengths, + * not aligned lengths. Indexing nodes also store real lengths in branches. + * + * UBIFS uses padding when it pads to the next min. I/O unit. In this case it + * uses padding nodes or padding bytes, if the padding node does not fit. + * + * All UBIFS nodes are protected by CRC checksums and UBIFS checks CRC when + * they are read from the flash media. + */ + +#include "kmem.h" +#include "crc32.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" + +/** + * ubifs_ro_mode - switch UBIFS to read read-only mode. + * @c: UBIFS file-system description object + * @err: error code which is the reason of switching to R/O mode + */ +void ubifs_ro_mode(struct ubifs_info *c, int err) +{ + if (!c->ro_error) { + c->ro_error = 1; + c->no_chk_data_crc = 0; + ubifs_warn(c, "switched to read-only mode, error %d", err); + dump_stack(); + } +} + +/* + * Below are simple wrappers over UBI I/O functions which include some + * additional checks and UBIFS debugging stuff. See corresponding UBI function + * for more information. + */ + +int ubifs_leb_read(const struct ubifs_info *c, int lnum, void *buf, int offs, + int len, int even_ebadmsg) +{ + int err = 0; + off_t pos = (off_t)lnum * c->leb_size + offs; + + if (!len) + return 0; + + /* + * The %-EBADMSG may be ignored in some case, the buf may not be filled + * with data in some buggy mtd drivers. So we'd better to reset the buf + * content before reading. + */ + memset(buf, 0, len); + if (lseek(c->dev_fd, pos, SEEK_SET) != pos) { + err = -errno; + goto out; + } + + if (read(c->dev_fd, buf, len) != len) + err = -errno; +out: + /* + * In case of %-EBADMSG print the error message only if the + * @even_ebadmsg is true. + */ + if (err && (err != -EBADMSG || even_ebadmsg)) { + ubifs_err(c, "reading %d bytes from LEB %d:%d failed, error %d", + len, lnum, offs, err); + dump_stack(); + } + return err; +} + +int ubifs_leb_write(struct ubifs_info *c, int lnum, const void *buf, int offs, + int len) +{ + int err = 0; + off_t pos = (off_t)lnum * c->leb_size + offs; + + ubifs_assert(c, !c->ro_media && !c->ro_mount); + if (c->ro_error) + return -EROFS; + if (!c->libubi) { + err = -ENODEV; + goto out; + } + + if (!len) + return 0; + + if (lseek(c->dev_fd, pos, SEEK_SET) != pos) { + err = -errno; + goto out; + } + if (write(c->dev_fd, buf, len) != len) + err = -errno; +out: + if (err) { + ubifs_err(c, "writing %d bytes to LEB %d:%d failed, error %d", + len, lnum, offs, err); + ubifs_ro_mode(c, err); + dump_stack(); + } + return err; +} + +int ubifs_leb_change(struct ubifs_info *c, int lnum, const void *buf, int len) +{ + int err = 0; + off_t pos = (off_t)lnum * c->leb_size; + + ubifs_assert(c, !c->ro_media && !c->ro_mount); + if (c->ro_error) + return -EROFS; + if (c->libubi) { + err = ubi_leb_change_start(c->libubi, c->dev_fd, lnum, len); + if (err) { + ubifs_err(c, "ubi_leb_change_start failed"); + err = -errno; + goto out; + } + } + + if (!len) + return 0; + + if (lseek(c->dev_fd, pos, SEEK_SET) != pos) { + err = -errno; + goto out; + } + if (write(c->dev_fd, buf, len) != len) + err = -errno; +out: + if (err) { + ubifs_err(c, "changing %d bytes in LEB %d failed, error %d", + len, lnum, err); + ubifs_ro_mode(c, err); + dump_stack(); + } + return err; +} + +int ubifs_leb_unmap(struct ubifs_info *c, int lnum) +{ + int err = 0; + + ubifs_assert(c, !c->ro_media && !c->ro_mount); + if (c->ro_error) + return -EROFS; + if (!c->libubi) + return -ENODEV; + if (ubi_leb_unmap(c->dev_fd, lnum)) + err = -errno; + if (err) { + ubifs_err(c, "unmap LEB %d failed, error %d", lnum, err); + ubifs_ro_mode(c, err); + dump_stack(); + } + return err; +} + +int ubifs_leb_map(struct ubifs_info *c, int lnum) +{ + int err = 0; + + ubifs_assert(c, !c->ro_media && !c->ro_mount); + if (c->ro_error) + return -EROFS; + if (!c->libubi) + return -ENODEV; + if (ubi_leb_map(c->dev_fd, lnum)) + err = -errno; + if (err) { + ubifs_err(c, "mapping LEB %d failed, error %d", lnum, err); + ubifs_ro_mode(c, err); + dump_stack(); + } + return err; +} + +int ubifs_is_mapped(const struct ubifs_info *c, int lnum) +{ + int err = 0; + + if (!c->libubi) + return -ENODEV; + if (ubi_is_mapped(c->dev_fd, lnum)) + err = -errno; + if (err < 0) { + ubifs_err(c, "ubi_is_mapped failed for LEB %d, error %d", + lnum, err); + dump_stack(); + } + return err; +} + +/** + * ubifs_check_node - check node. + * @c: UBIFS file-system description object + * @buf: node to check + * @len: node length + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * @quiet: print no messages + * @must_chk_crc: indicates whether to always check the CRC + * + * This function checks node magic number and CRC checksum. This function also + * validates node length to prevent UBIFS from becoming crazy when an attacker + * feeds it a file-system image with incorrect nodes. For example, too large + * node length in the common header could cause UBIFS to read memory outside of + * allocated buffer when checking the CRC checksum. + * + * This function may skip data nodes CRC checking if @c->no_chk_data_crc is + * true, which is controlled by corresponding UBIFS mount option. However, if + * @must_chk_crc is true, then @c->no_chk_data_crc is ignored and CRC is + * checked. Similarly, if @c->mounting or @c->remounting_rw is true (we are + * mounting or re-mounting to R/W mode), @c->no_chk_data_crc is ignored and CRC + * is checked. This is because during mounting or re-mounting from R/O mode to + * R/W mode we may read journal nodes (when replying the journal or doing the + * recovery) and the journal nodes may potentially be corrupted, so checking is + * required. + * + * This function returns zero in case of success and %-EUCLEAN in case of bad + * CRC or magic. + */ +int ubifs_check_node(const struct ubifs_info *c, const void *buf, int len, + int lnum, int offs, int quiet, int must_chk_crc) +{ + int err = -EINVAL, type, node_len; + uint32_t crc, node_crc, magic; + const struct ubifs_ch *ch = buf; + + ubifs_assert(c, lnum >= 0 && lnum < c->leb_cnt && offs >= 0); + ubifs_assert(c, !(offs & 7) && offs < c->leb_size); + + magic = le32_to_cpu(ch->magic); + if (magic != UBIFS_NODE_MAGIC) { + if (!quiet) + ubifs_err(c, "bad magic %#08x, expected %#08x", + magic, UBIFS_NODE_MAGIC); + err = -EUCLEAN; + goto out; + } + + type = ch->node_type; + if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) { + if (!quiet) + ubifs_err(c, "bad node type %d", type); + goto out; + } + + node_len = le32_to_cpu(ch->len); + if (node_len + offs > c->leb_size) + goto out_len; + + if (c->ranges[type].max_len == 0) { + if (node_len != c->ranges[type].len) + goto out_len; + } else if (node_len < c->ranges[type].min_len || + node_len > c->ranges[type].max_len) + goto out_len; + + if (!must_chk_crc && type == UBIFS_DATA_NODE && !c->mounting && + !c->remounting_rw && c->no_chk_data_crc) + return 0; + + crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8); + node_crc = le32_to_cpu(ch->crc); + if (crc != node_crc) { + if (!quiet) + ubifs_err(c, "bad CRC: calculated %#08x, read %#08x", + crc, node_crc); + err = -EUCLEAN; + goto out; + } + + return 0; + +out_len: + if (!quiet) + ubifs_err(c, "bad node length %d", node_len); +out: + if (!quiet) { + ubifs_err(c, "bad node at LEB %d:%d", lnum, offs); + ubifs_dump_node(c, buf, len); + dump_stack(); + } + return err; +} + +/** + * ubifs_pad - pad flash space. + * @c: UBIFS file-system description object + * @buf: buffer to put padding to + * @pad: how many bytes to pad + * + * The flash media obliges us to write only in chunks of %c->min_io_size and + * when we have to write less data we add padding node to the write-buffer and + * pad it to the next minimal I/O unit's boundary. Padding nodes help when the + * media is being scanned. If the amount of wasted space is not enough to fit a + * padding node which takes %UBIFS_PAD_NODE_SZ bytes, we write padding bytes + * pattern (%UBIFS_PADDING_BYTE). + * + * Padding nodes are also used to fill gaps when the "commit-in-gaps" method is + * used. + */ +void ubifs_pad(const struct ubifs_info *c, void *buf, int pad) +{ + uint32_t crc; + + ubifs_assert(c, pad >= 0); + + if (pad >= UBIFS_PAD_NODE_SZ) { + struct ubifs_ch *ch = buf; + struct ubifs_pad_node *pad_node = buf; + + ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC); + ch->node_type = UBIFS_PAD_NODE; + ch->group_type = UBIFS_NO_NODE_GROUP; + ch->padding[0] = ch->padding[1] = 0; + ch->sqnum = 0; + ch->len = cpu_to_le32(UBIFS_PAD_NODE_SZ); + pad -= UBIFS_PAD_NODE_SZ; + pad_node->pad_len = cpu_to_le32(pad); + crc = crc32(UBIFS_CRC32_INIT, buf + 8, UBIFS_PAD_NODE_SZ - 8); + ch->crc = cpu_to_le32(crc); + memset(buf + UBIFS_PAD_NODE_SZ, 0, pad); + } else if (pad > 0) + /* Too little space, padding node won't fit */ + memset(buf, UBIFS_PADDING_BYTE, pad); +} + +/** + * next_sqnum - get next sequence number. + * @c: UBIFS file-system description object + */ +static unsigned long long next_sqnum(struct ubifs_info *c) +{ + unsigned long long sqnum; + + spin_lock(&c->cnt_lock); + sqnum = ++c->max_sqnum; + spin_unlock(&c->cnt_lock); + + if (unlikely(sqnum >= SQNUM_WARN_WATERMARK)) { + if (sqnum >= SQNUM_WATERMARK) { + ubifs_err(c, "sequence number overflow %llu, end of life", + sqnum); + ubifs_ro_mode(c, -EINVAL); + } + ubifs_warn(c, "running out of sequence numbers, end of life soon"); + } + + return sqnum; +} + +void ubifs_init_node(struct ubifs_info *c, void *node, int len, int pad) +{ + struct ubifs_ch *ch = node; + unsigned long long sqnum = next_sqnum(c); + + ubifs_assert(c, len >= UBIFS_CH_SZ); + + ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC); + ch->len = cpu_to_le32(len); + ch->group_type = UBIFS_NO_NODE_GROUP; + ch->sqnum = cpu_to_le64(sqnum); + ch->padding[0] = ch->padding[1] = 0; + + if (pad) { + len = ALIGN(len, 8); + pad = ALIGN(len, c->min_io_size) - len; + ubifs_pad(c, node + len, pad); + } +} + +void ubifs_crc_node(__unused struct ubifs_info *c, void *node, int len) +{ + struct ubifs_ch *ch = node; + uint32_t crc; + + crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8); + ch->crc = cpu_to_le32(crc); +} + +/** + * ubifs_prepare_node_hmac - prepare node to be written to flash. + * @c: UBIFS file-system description object + * @node: the node to pad + * @len: node length + * @hmac_offs: offset of the HMAC in the node + * @pad: if the buffer has to be padded + * + * This function prepares node at @node to be written to the media - it + * calculates node CRC, fills the common header, and adds proper padding up to + * the next minimum I/O unit if @pad is not zero. if @hmac_offs is positive then + * a HMAC is inserted into the node at the given offset. + * + * This function returns 0 for success or a negative error code otherwise. + */ +int ubifs_prepare_node_hmac(struct ubifs_info *c, void *node, int len, + int hmac_offs, int pad) +{ + int err; + + ubifs_init_node(c, node, len, pad); + + if (hmac_offs > 0) { + err = ubifs_node_insert_hmac(c, node, len, hmac_offs); + if (err) + return err; + } + + ubifs_crc_node(c, node, len); + + return 0; +} + +/** + * ubifs_prepare_node - prepare node to be written to flash. + * @c: UBIFS file-system description object + * @node: the node to pad + * @len: node length + * @pad: if the buffer has to be padded + * + * This function prepares node at @node to be written to the media - it + * calculates node CRC, fills the common header, and adds proper padding up to + * the next minimum I/O unit if @pad is not zero. + */ +void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad) +{ + /* + * Deliberately ignore return value since this function can only fail + * when a hmac offset is given. + */ + ubifs_prepare_node_hmac(c, node, len, 0, pad); +} + +/** + * ubifs_prep_grp_node - prepare node of a group to be written to flash. + * @c: UBIFS file-system description object + * @node: the node to pad + * @len: node length + * @last: indicates the last node of the group + * + * This function prepares node at @node to be written to the media - it + * calculates node CRC and fills the common header. + */ +void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last) +{ + uint32_t crc; + struct ubifs_ch *ch = node; + unsigned long long sqnum = next_sqnum(c); + + ubifs_assert(c, len >= UBIFS_CH_SZ); + + ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC); + ch->len = cpu_to_le32(len); + if (last) + ch->group_type = UBIFS_LAST_OF_NODE_GROUP; + else + ch->group_type = UBIFS_IN_NODE_GROUP; + ch->sqnum = cpu_to_le64(sqnum); + ch->padding[0] = ch->padding[1] = 0; + crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8); + ch->crc = cpu_to_le32(crc); +} + +/** + * ubifs_wbuf_sync_nolock - synchronize write-buffer. + * @wbuf: write-buffer to synchronize + * + * This function synchronizes write-buffer @buf and returns zero in case of + * success or a negative error code in case of failure. + * + * Note, although write-buffers are of @c->max_write_size, this function does + * not necessarily writes all @c->max_write_size bytes to the flash. Instead, + * if the write-buffer is only partially filled with data, only the used part + * of the write-buffer (aligned on @c->min_io_size boundary) is synchronized. + * This way we waste less space. + */ +int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf) +{ + struct ubifs_info *c = wbuf->c; + int err, dirt, sync_len; + + if (!wbuf->used || wbuf->lnum == -1) + /* Write-buffer is empty or not seeked */ + return 0; + + dbg_io("LEB %d:%d, %d bytes, jhead %s", + wbuf->lnum, wbuf->offs, wbuf->used, dbg_jhead(wbuf->jhead)); + ubifs_assert(c, !(wbuf->avail & 7)); + ubifs_assert(c, wbuf->offs + wbuf->size <= c->leb_size); + ubifs_assert(c, wbuf->size >= c->min_io_size); + ubifs_assert(c, wbuf->size <= c->max_write_size); + ubifs_assert(c, wbuf->size % c->min_io_size == 0); + ubifs_assert(c, !c->ro_media && !c->ro_mount); + if (c->leb_size - wbuf->offs >= c->max_write_size) + ubifs_assert(c, !((wbuf->offs + wbuf->size) % c->max_write_size)); + + if (c->ro_error) + return -EROFS; + + /* + * Do not write whole write buffer but write only the minimum necessary + * amount of min. I/O units. + */ + sync_len = ALIGN(wbuf->used, c->min_io_size); + dirt = sync_len - wbuf->used; + if (dirt) + ubifs_pad(c, wbuf->buf + wbuf->used, dirt); + err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, wbuf->offs, sync_len); + if (err) + return err; + + spin_lock(&wbuf->lock); + wbuf->offs += sync_len; + /* + * Now @wbuf->offs is not necessarily aligned to @c->max_write_size. + * But our goal is to optimize writes and make sure we write in + * @c->max_write_size chunks and to @c->max_write_size-aligned offset. + * Thus, if @wbuf->offs is not aligned to @c->max_write_size now, make + * sure that @wbuf->offs + @wbuf->size is aligned to + * @c->max_write_size. This way we make sure that after next + * write-buffer flush we are again at the optimal offset (aligned to + * @c->max_write_size). + */ + if (c->leb_size - wbuf->offs < c->max_write_size) + wbuf->size = c->leb_size - wbuf->offs; + else if (wbuf->offs & (c->max_write_size - 1)) + wbuf->size = ALIGN(wbuf->offs, c->max_write_size) - wbuf->offs; + else + wbuf->size = c->max_write_size; + wbuf->avail = wbuf->size; + wbuf->used = 0; + wbuf->next_ino = 0; + spin_unlock(&wbuf->lock); + + if (wbuf->sync_callback) + err = wbuf->sync_callback(c, wbuf->lnum, + c->leb_size - wbuf->offs, dirt); + return err; +} + +/** + * ubifs_wbuf_seek_nolock - seek write-buffer. + * @wbuf: write-buffer + * @lnum: logical eraseblock number to seek to + * @offs: logical eraseblock offset to seek to + * + * This function targets the write-buffer to logical eraseblock @lnum:@offs. + * The write-buffer has to be empty. Returns zero in case of success and a + * negative error code in case of failure. + */ +int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs) +{ + const struct ubifs_info *c = wbuf->c; + + dbg_io("LEB %d:%d, jhead %s", lnum, offs, dbg_jhead(wbuf->jhead)); + ubifs_assert(c, lnum >= 0 && lnum < c->leb_cnt); + ubifs_assert(c, offs >= 0 && offs <= c->leb_size); + ubifs_assert(c, offs % c->min_io_size == 0 && !(offs & 7)); + ubifs_assert(c, lnum != wbuf->lnum); + ubifs_assert(c, wbuf->used == 0); + + spin_lock(&wbuf->lock); + wbuf->lnum = lnum; + wbuf->offs = offs; + if (c->leb_size - wbuf->offs < c->max_write_size) + wbuf->size = c->leb_size - wbuf->offs; + else if (wbuf->offs & (c->max_write_size - 1)) + wbuf->size = ALIGN(wbuf->offs, c->max_write_size) - wbuf->offs; + else + wbuf->size = c->max_write_size; + wbuf->avail = wbuf->size; + wbuf->used = 0; + spin_unlock(&wbuf->lock); + + return 0; +} + +/** + * ubifs_wbuf_write_nolock - write data to flash via write-buffer. + * @wbuf: write-buffer + * @buf: node to write + * @len: node length + * + * This function writes data to flash via write-buffer @wbuf. This means that + * the last piece of the node won't reach the flash media immediately if it + * does not take whole max. write unit (@c->max_write_size). Instead, the node + * will sit in RAM until the write-buffer is synchronized (e.g., by timer, or + * because more data are appended to the write-buffer). + * + * This function returns zero in case of success and a negative error code in + * case of failure. If the node cannot be written because there is no more + * space in this logical eraseblock, %-ENOSPC is returned. + */ +int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len) +{ + struct ubifs_info *c = wbuf->c; + int err, n, written = 0, aligned_len = ALIGN(len, 8); + + dbg_io("%d bytes (%s) to jhead %s wbuf at LEB %d:%d", len, + dbg_ntype(((struct ubifs_ch *)buf)->node_type), + dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs + wbuf->used); + ubifs_assert(c, len > 0 && wbuf->lnum >= 0 && wbuf->lnum < c->leb_cnt); + ubifs_assert(c, wbuf->offs >= 0 && wbuf->offs % c->min_io_size == 0); + ubifs_assert(c, !(wbuf->offs & 7) && wbuf->offs <= c->leb_size); + ubifs_assert(c, wbuf->avail > 0 && wbuf->avail <= wbuf->size); + ubifs_assert(c, wbuf->size >= c->min_io_size); + ubifs_assert(c, wbuf->size <= c->max_write_size); + ubifs_assert(c, wbuf->size % c->min_io_size == 0); + ubifs_assert(c, mutex_is_locked(&wbuf->io_mutex)); + ubifs_assert(c, !c->ro_media && !c->ro_mount); + ubifs_assert(c, !c->space_fixup); + if (c->leb_size - wbuf->offs >= c->max_write_size) + ubifs_assert(c, !((wbuf->offs + wbuf->size) % c->max_write_size)); + + if (c->leb_size - wbuf->offs - wbuf->used < aligned_len) { + err = -ENOSPC; + goto out; + } + + if (c->ro_error) + return -EROFS; + + if (aligned_len <= wbuf->avail) { + /* + * The node is not very large and fits entirely within + * write-buffer. + */ + memcpy(wbuf->buf + wbuf->used, buf, len); + if (aligned_len > len) { + ubifs_assert(c, aligned_len - len < 8); + ubifs_pad(c, wbuf->buf + wbuf->used + len, aligned_len - len); + } + + if (aligned_len == wbuf->avail) { + dbg_io("flush jhead %s wbuf to LEB %d:%d", + dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs); + err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, + wbuf->offs, wbuf->size); + if (err) + goto out; + + spin_lock(&wbuf->lock); + wbuf->offs += wbuf->size; + if (c->leb_size - wbuf->offs >= c->max_write_size) + wbuf->size = c->max_write_size; + else + wbuf->size = c->leb_size - wbuf->offs; + wbuf->avail = wbuf->size; + wbuf->used = 0; + wbuf->next_ino = 0; + spin_unlock(&wbuf->lock); + } else { + spin_lock(&wbuf->lock); + wbuf->avail -= aligned_len; + wbuf->used += aligned_len; + spin_unlock(&wbuf->lock); + } + + goto exit; + } + + if (wbuf->used) { + /* + * The node is large enough and does not fit entirely within + * current available space. We have to fill and flush + * write-buffer and switch to the next max. write unit. + */ + dbg_io("flush jhead %s wbuf to LEB %d:%d", + dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs); + memcpy(wbuf->buf + wbuf->used, buf, wbuf->avail); + err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, wbuf->offs, + wbuf->size); + if (err) + goto out; + + wbuf->offs += wbuf->size; + len -= wbuf->avail; + aligned_len -= wbuf->avail; + written += wbuf->avail; + } else if (wbuf->offs & (c->max_write_size - 1)) { + /* + * The write-buffer offset is not aligned to + * @c->max_write_size and @wbuf->size is less than + * @c->max_write_size. Write @wbuf->size bytes to make sure the + * following writes are done in optimal @c->max_write_size + * chunks. + */ + dbg_io("write %d bytes to LEB %d:%d", + wbuf->size, wbuf->lnum, wbuf->offs); + err = ubifs_leb_write(c, wbuf->lnum, buf, wbuf->offs, + wbuf->size); + if (err) + goto out; + + wbuf->offs += wbuf->size; + len -= wbuf->size; + aligned_len -= wbuf->size; + written += wbuf->size; + } + + /* + * The remaining data may take more whole max. write units, so write the + * remains multiple to max. write unit size directly to the flash media. + * We align node length to 8-byte boundary because we anyway flash wbuf + * if the remaining space is less than 8 bytes. + */ + n = aligned_len >> c->max_write_shift; + if (n) { + int m = n - 1; + + dbg_io("write %d bytes to LEB %d:%d", n, wbuf->lnum, + wbuf->offs); + + if (m) { + /* '(n-1)<<c->max_write_shift < len' is always true. */ + m <<= c->max_write_shift; + err = ubifs_leb_write(c, wbuf->lnum, buf + written, + wbuf->offs, m); + if (err) + goto out; + wbuf->offs += m; + aligned_len -= m; + len -= m; + written += m; + } + + /* + * The non-written len of buf may be less than 'n' because + * parameter 'len' is not 8 bytes aligned, so here we read + * min(len, n) bytes from buf. + */ + n = 1 << c->max_write_shift; + memcpy(wbuf->buf, buf + written, min(len, n)); + if (n > len) { + ubifs_assert(c, n - len < 8); + ubifs_pad(c, wbuf->buf + len, n - len); + } + + err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, wbuf->offs, n); + if (err) + goto out; + wbuf->offs += n; + aligned_len -= n; + len -= min(len, n); + written += n; + } + + spin_lock(&wbuf->lock); + if (aligned_len) { + /* + * And now we have what's left and what does not take whole + * max. write unit, so write it to the write-buffer and we are + * done. + */ + memcpy(wbuf->buf, buf + written, len); + if (aligned_len > len) { + ubifs_assert(c, aligned_len - len < 8); + ubifs_pad(c, wbuf->buf + len, aligned_len - len); + } + } + + if (c->leb_size - wbuf->offs >= c->max_write_size) + wbuf->size = c->max_write_size; + else + wbuf->size = c->leb_size - wbuf->offs; + wbuf->avail = wbuf->size - aligned_len; + wbuf->used = aligned_len; + wbuf->next_ino = 0; + spin_unlock(&wbuf->lock); + +exit: + if (wbuf->sync_callback) { + int free = c->leb_size - wbuf->offs - wbuf->used; + + err = wbuf->sync_callback(c, wbuf->lnum, free, 0); + if (err) + goto out; + } + + return 0; + +out: + ubifs_err(c, "cannot write %d bytes to LEB %d:%d, error %d", + len, wbuf->lnum, wbuf->offs, err); + ubifs_dump_node(c, buf, written + len); + dump_stack(); + ubifs_dump_leb(c, wbuf->lnum); + return err; +} + +/** + * ubifs_write_node_hmac - write node to the media. + * @c: UBIFS file-system description object + * @buf: the node to write + * @len: node length + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * @hmac_offs: offset of the HMAC within the node + * + * This function automatically fills node magic number, assigns sequence + * number, and calculates node CRC checksum. The length of the @buf buffer has + * to be aligned to the minimal I/O unit size. This function automatically + * appends padding node and padding bytes if needed. Returns zero in case of + * success and a negative error code in case of failure. + */ +int ubifs_write_node_hmac(struct ubifs_info *c, void *buf, int len, int lnum, + int offs, int hmac_offs) +{ + int err, buf_len = ALIGN(len, c->min_io_size); + + dbg_io("LEB %d:%d, %s, length %d (aligned %d)", + lnum, offs, dbg_ntype(((struct ubifs_ch *)buf)->node_type), len, + buf_len); + ubifs_assert(c, lnum >= 0 && lnum < c->leb_cnt && offs >= 0); + ubifs_assert(c, offs % c->min_io_size == 0 && offs < c->leb_size); + ubifs_assert(c, !c->ro_media && !c->ro_mount); + ubifs_assert(c, !c->space_fixup); + + if (c->ro_error) + return -EROFS; + + err = ubifs_prepare_node_hmac(c, buf, len, hmac_offs, 1); + if (err) + return err; + + err = ubifs_leb_write(c, lnum, buf, offs, buf_len); + if (err) + ubifs_dump_node(c, buf, len); + + return err; +} + +/** + * ubifs_write_node - write node to the media. + * @c: UBIFS file-system description object + * @buf: the node to write + * @len: node length + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * + * This function automatically fills node magic number, assigns sequence + * number, and calculates node CRC checksum. The length of the @buf buffer has + * to be aligned to the minimal I/O unit size. This function automatically + * appends padding node and padding bytes if needed. Returns zero in case of + * success and a negative error code in case of failure. + */ +int ubifs_write_node(struct ubifs_info *c, void *buf, int len, int lnum, + int offs) +{ + return ubifs_write_node_hmac(c, buf, len, lnum, offs, -1); +} + +/** + * ubifs_read_node_wbuf - read node from the media or write-buffer. + * @wbuf: wbuf to check for un-written data + * @buf: buffer to read to + * @type: node type + * @len: node length + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * + * This function reads a node of known type and length, checks it and stores + * in @buf. If the node partially or fully sits in the write-buffer, this + * function takes data from the buffer, otherwise it reads the flash media. + * Returns zero in case of success, %-EUCLEAN if CRC mismatched and a negative + * error code in case of failure. + */ +int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len, + int lnum, int offs) +{ + const struct ubifs_info *c = wbuf->c; + int err, rlen, overlap; + struct ubifs_ch *ch = buf; + + dbg_io("LEB %d:%d, %s, length %d, jhead %s", lnum, offs, + dbg_ntype(type), len, dbg_jhead(wbuf->jhead)); + ubifs_assert(c, wbuf && lnum >= 0 && lnum < c->leb_cnt && offs >= 0); + ubifs_assert(c, !(offs & 7) && offs < c->leb_size); + ubifs_assert(c, type >= 0 && type < UBIFS_NODE_TYPES_CNT); + + spin_lock(&wbuf->lock); + overlap = (lnum == wbuf->lnum && offs + len > wbuf->offs); + if (!overlap) { + /* We may safely unlock the write-buffer and read the data */ + spin_unlock(&wbuf->lock); + return ubifs_read_node(c, buf, type, len, lnum, offs); + } + + /* Don't read under wbuf */ + rlen = wbuf->offs - offs; + if (rlen < 0) + rlen = 0; + + /* Copy the rest from the write-buffer */ + memcpy(buf + rlen, wbuf->buf + offs + rlen - wbuf->offs, len - rlen); + spin_unlock(&wbuf->lock); + + if (rlen > 0) { + /* Read everything that goes before write-buffer */ + err = ubifs_leb_read(c, lnum, buf, offs, rlen, 0); + if (err && err != -EBADMSG) + return err; + } + + if (type != ch->node_type) { + ubifs_err(c, "bad node type (%d but expected %d)", + ch->node_type, type); + goto out; + } + + err = ubifs_check_node(c, buf, len, lnum, offs, 0, 0); + if (err) { + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "expected node type %d", type); + return err; + } + + rlen = le32_to_cpu(ch->len); + if (rlen != len) { + ubifs_err(c, "bad node length %d, expected %d", rlen, len); + goto out; + } + + return 0; + +out: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "bad node at LEB %d:%d", lnum, offs); + ubifs_dump_node(c, buf, len); + dump_stack(); + return -EINVAL; +} + +/** + * ubifs_read_node - read node. + * @c: UBIFS file-system description object + * @buf: buffer to read to + * @type: node type + * @len: node length (not aligned) + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * + * This function reads a node of known type and length, checks it and + * stores in @buf. Returns zero in case of success, %-EUCLEAN if CRC mismatched + * and a negative error code in case of failure. + */ +int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len, + int lnum, int offs) +{ + int err, l; + struct ubifs_ch *ch = buf; + + dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len); + ubifs_assert(c, lnum >= 0 && lnum < c->leb_cnt && offs >= 0); + ubifs_assert(c, len >= UBIFS_CH_SZ && offs + len <= c->leb_size); + ubifs_assert(c, !(offs & 7) && offs < c->leb_size); + ubifs_assert(c, type >= 0 && type < UBIFS_NODE_TYPES_CNT); + + err = ubifs_leb_read(c, lnum, buf, offs, len, 0); + if (err && err != -EBADMSG) + return err; + + if (type != ch->node_type) { + ubifs_err(c, "bad node type (%d but expected %d)", + ch->node_type, type); + goto out; + } + + err = ubifs_check_node(c, buf, len, lnum, offs, 0, 0); + if (err) { + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "expected node type %d", type); + return err; + } + + l = le32_to_cpu(ch->len); + if (l != len) { + ubifs_err(c, "bad node length %d, expected %d", l, len); + goto out; + } + + return 0; + +out: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "bad node at LEB %d:%d, LEB mapping status %d", lnum, + offs, ubi_is_mapped(c->dev_fd, lnum)); + ubifs_dump_node(c, buf, len); + dump_stack(); + return -EINVAL; +} + +/** + * ubifs_wbuf_init - initialize write-buffer. + * @c: UBIFS file-system description object + * @wbuf: write-buffer to initialize + * + * This function initializes write-buffer. Returns zero in case of success + * %-ENOMEM in case of failure. + */ +int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf) +{ + size_t size; + + wbuf->buf = kmalloc(c->max_write_size, GFP_KERNEL); + if (!wbuf->buf) + return -ENOMEM; + + size = (c->max_write_size / UBIFS_CH_SZ + 1) * sizeof(ino_t); + wbuf->inodes = kmalloc(size, GFP_KERNEL); + if (!wbuf->inodes) { + kfree(wbuf->buf); + wbuf->buf = NULL; + return -ENOMEM; + } + + wbuf->used = 0; + wbuf->lnum = wbuf->offs = -1; + /* + * Different from linux kernel, there is no way to get leb_start in + * userspace, set write-buffer size as @c->max_write_size directly. + * Since wbuf->lnum is initialized as -1, wbuf->size will always be + * reset in ubifs_wbuf_seek_nolock, it won't be any problems. + */ + size = c->max_write_size; + wbuf->avail = wbuf->size = size; + wbuf->sync_callback = NULL; + mutex_init(&wbuf->io_mutex); + spin_lock_init(&wbuf->lock); + wbuf->c = c; + wbuf->next_ino = 0; + + return 0; +} diff --git a/ubifs-utils/libubifs/journal.c b/ubifs-utils/libubifs/journal.c new file mode 100644 index 0000000..45d82fd --- /dev/null +++ b/ubifs-utils/libubifs/journal.c @@ -0,0 +1,634 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements UBIFS journal. + * + * The journal consists of 2 parts - the log and bud LEBs. The log has fixed + * length and position, while a bud logical eraseblock is any LEB in the main + * area. Buds contain file system data - data nodes, inode nodes, etc. The log + * contains only references to buds and some other stuff like commit + * start node. The idea is that when we commit the journal, we do + * not copy the data, the buds just become indexed. Since after the commit the + * nodes in bud eraseblocks become leaf nodes of the file system index tree, we + * use term "bud". Analogy is obvious, bud eraseblocks contain nodes which will + * become leafs in the future. + * + * The journal is multi-headed because we want to write data to the journal as + * optimally as possible. It is nice to have nodes belonging to the same inode + * in one LEB, so we may write data owned by different inodes to different + * journal heads, although at present only one data head is used. + * + * For recovery reasons, the base head contains all inode nodes, all directory + * entry nodes and all truncate nodes. This means that the other heads contain + * only data nodes. + * + * Bud LEBs may be half-indexed. For example, if the bud was not full at the + * time of commit, the bud is retained to continue to be used in the journal, + * even though the "front" of the LEB is now indexed. In that case, the log + * reference contains the offset where the bud starts for the purposes of the + * journal. + * + * The journal size has to be limited, because the larger is the journal, the + * longer it takes to mount UBIFS (scanning the journal) and the more memory it + * takes (indexing in the TNC). + * + * All the journal write operations like 'ubifs_jnl_update()' here, which write + * multiple UBIFS nodes to the journal at one go, are atomic with respect to + * unclean reboots. Should the unclean reboot happen, the recovery code drops + * all the nodes. + */ + +#include <sys/stat.h> +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/** + * zero_ino_node_unused - zero out unused fields of an on-flash inode node. + * @ino: the inode to zero out + */ +static inline void zero_ino_node_unused(struct ubifs_ino_node *ino) +{ + memset(ino->padding1, 0, 4); + memset(ino->padding2, 0, 26); +} + +/** + * zero_dent_node_unused - zero out unused fields of an on-flash directory + * entry node. + * @dent: the directory entry to zero out + */ +static inline void zero_dent_node_unused(struct ubifs_dent_node *dent) +{ + dent->padding1 = 0; +} + +static void ubifs_add_auth_dirt(struct ubifs_info *c, int lnum) +{ + if (ubifs_authenticated(c)) + ubifs_add_dirt(c, lnum, ubifs_auth_node_sz(c)); +} + +/** + * reserve_space - reserve space in the journal. + * @c: UBIFS file-system description object + * @jhead: journal head number + * @len: node length + * + * This function reserves space in journal head @head. If the reservation + * succeeded, the journal head stays locked and later has to be unlocked using + * 'release_head()'. Returns zero in case of success, %-EAGAIN if commit has to + * be done, and other negative error codes in case of other failures. + */ +static int reserve_space(struct ubifs_info *c, int jhead, int len) +{ + int err = 0, err1, retries = 0, avail, lnum, offs, squeeze; + struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf; + + /* + * Typically, the base head has smaller nodes written to it, so it is + * better to try to allocate space at the ends of eraseblocks. This is + * what the squeeze parameter does. + */ + ubifs_assert(c, !c->ro_media && !c->ro_mount); + squeeze = (jhead == BASEHD); +again: + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + + if (c->ro_error) { + err = -EROFS; + goto out_unlock; + } + + avail = c->leb_size - wbuf->offs - wbuf->used; + if (wbuf->lnum != -1 && avail >= len) + return 0; + + /* + * Write buffer wasn't seek'ed or there is no enough space - look for an + * LEB with some empty space. + */ + lnum = ubifs_find_free_space(c, len, &offs, squeeze); + if (lnum >= 0) + goto out; + + err = lnum; + if (err != -ENOSPC) + goto out_unlock; + + /* + * No free space, we have to run garbage collector to make + * some. But the write-buffer mutex has to be unlocked because + * GC also takes it. + */ + dbg_jnl("no free space in jhead %s, run GC", dbg_jhead(jhead)); + mutex_unlock(&wbuf->io_mutex); + + lnum = ubifs_garbage_collect(c, 0); + if (lnum < 0) { + err = lnum; + if (err != -ENOSPC) + return err; + + /* + * GC could not make a free LEB. But someone else may + * have allocated new bud for this journal head, + * because we dropped @wbuf->io_mutex, so try once + * again. + */ + dbg_jnl("GC couldn't make a free LEB for jhead %s", + dbg_jhead(jhead)); + if (retries++ < 2) { + dbg_jnl("retry (%d)", retries); + goto again; + } + + dbg_jnl("return -ENOSPC"); + return err; + } + + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + dbg_jnl("got LEB %d for jhead %s", lnum, dbg_jhead(jhead)); + avail = c->leb_size - wbuf->offs - wbuf->used; + + if (wbuf->lnum != -1 && avail >= len) { + /* + * Someone else has switched the journal head and we have + * enough space now. This happens when more than one process is + * trying to write to the same journal head at the same time. + */ + dbg_jnl("return LEB %d back, already have LEB %d:%d", + lnum, wbuf->lnum, wbuf->offs + wbuf->used); + err = ubifs_return_leb(c, lnum); + if (err) + goto out_unlock; + return 0; + } + + offs = 0; + +out: + /* + * Make sure we synchronize the write-buffer before we add the new bud + * to the log. Otherwise we may have a power cut after the log + * reference node for the last bud (@lnum) is written but before the + * write-buffer data are written to the next-to-last bud + * (@wbuf->lnum). And the effect would be that the recovery would see + * that there is corruption in the next-to-last bud. + */ + err = ubifs_wbuf_sync_nolock(wbuf); + if (err) + goto out_return; + err = ubifs_add_bud_to_log(c, jhead, lnum, offs); + if (err) + goto out_return; + err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs); + if (err) + goto out_unlock; + + return 0; + +out_unlock: + mutex_unlock(&wbuf->io_mutex); + return err; + +out_return: + /* An error occurred and the LEB has to be returned to lprops */ + ubifs_assert(c, err < 0); + err1 = ubifs_return_leb(c, lnum); + if (err1 && err == -EAGAIN) + /* + * Return original error code only if it is not %-EAGAIN, + * which is not really an error. Otherwise, return the error + * code of 'ubifs_return_leb()'. + */ + err = err1; + mutex_unlock(&wbuf->io_mutex); + return err; +} + +static int ubifs_hash_nodes(struct ubifs_info *c, void *node, + int len, struct shash_desc *hash) +{ + int auth_node_size = ubifs_auth_node_sz(c); + int err; + + while (1) { + const struct ubifs_ch *ch = node; + int nodelen = le32_to_cpu(ch->len); + + ubifs_assert(c, len >= auth_node_size); + + if (len == auth_node_size) + break; + + ubifs_assert(c, len > nodelen); + ubifs_assert(c, ch->magic == cpu_to_le32(UBIFS_NODE_MAGIC)); + + err = ubifs_shash_update(c, hash, (void *)node, nodelen); + if (err) + return err; + + node += ALIGN(nodelen, 8); + len -= ALIGN(nodelen, 8); + } + + return ubifs_prepare_auth_node(c, node, hash); +} + +/** + * write_head - write data to a journal head. + * @c: UBIFS file-system description object + * @jhead: journal head + * @buf: buffer to write + * @len: length to write + * @lnum: LEB number written is returned here + * @offs: offset written is returned here + * @sync: non-zero if the write-buffer has to by synchronized + * + * This function writes data to the reserved space of journal head @jhead. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +static int write_head(struct ubifs_info *c, int jhead, void *buf, int len, + int *lnum, int *offs, int sync) +{ + int err; + struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf; + + ubifs_assert(c, jhead != GCHD); + + *lnum = c->jheads[jhead].wbuf.lnum; + *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used; + dbg_jnl("jhead %s, LEB %d:%d, len %d", + dbg_jhead(jhead), *lnum, *offs, len); + + if (ubifs_authenticated(c)) { + err = ubifs_hash_nodes(c, buf, len, c->jheads[jhead].log_hash); + if (err) + return err; + } + + err = ubifs_wbuf_write_nolock(wbuf, buf, len); + if (err) + return err; + if (sync) + err = ubifs_wbuf_sync_nolock(wbuf); + return err; +} + +/** + * make_reservation - reserve journal space. + * @c: UBIFS file-system description object + * @jhead: journal head + * @len: how many bytes to reserve + * + * This function makes space reservation in journal head @jhead. The function + * takes the commit lock and locks the journal head, and the caller has to + * unlock the head and finish the reservation with 'finish_reservation()'. + * Returns zero in case of success and a negative error code in case of + * failure. + * + * Note, the journal head may be unlocked as soon as the data is written, while + * the commit lock has to be released after the data has been added to the + * TNC. + */ +static int make_reservation(struct ubifs_info *c, int jhead, int len) +{ + int err, cmt_retries = 0, nospc_retries = 0; + +again: + down_read(&c->commit_sem); + err = reserve_space(c, jhead, len); + if (!err) + /* c->commit_sem will get released via finish_reservation(). */ + return 0; + up_read(&c->commit_sem); + + if (err == -ENOSPC) { + /* + * GC could not make any progress. We should try to commit + * once because it could make some dirty space and GC would + * make progress, so make the error -EAGAIN so that the below + * will commit and re-try. + */ + if (nospc_retries++ < 2) { + dbg_jnl("no space, retry"); + err = -EAGAIN; + } + + /* + * This means that the budgeting is incorrect. We always have + * to be able to write to the media, because all operations are + * budgeted. Deletions are not budgeted, though, but we reserve + * an extra LEB for them. + */ + } + + if (err != -EAGAIN) + goto out; + + /* + * -EAGAIN means that the journal is full or too large, or the above + * code wants to do one commit. Do this and re-try. + */ + if (cmt_retries > 128) { + /* + * This should not happen unless the journal size limitations + * are too tough. + */ + ubifs_err(c, "stuck in space allocation"); + err = -ENOSPC; + goto out; + } else if (cmt_retries > 32) + ubifs_warn(c, "too many space allocation re-tries (%d)", + cmt_retries); + + dbg_jnl("-EAGAIN, commit and retry (retried %d times)", + cmt_retries); + cmt_retries += 1; + + err = ubifs_run_commit(c); + if (err) + return err; + goto again; + +out: + ubifs_err(c, "cannot reserve %d bytes in jhead %d, error %d", + len, jhead, err); + if (err == -ENOSPC) { + /* This are some budgeting problems, print useful information */ + down_write(&c->commit_sem); + dump_stack(); + ubifs_dump_budg(c, &c->bi); + ubifs_dump_lprops(c); + cmt_retries = dbg_check_lprops(c); + up_write(&c->commit_sem); + } + return err; +} + +/** + * release_head - release a journal head. + * @c: UBIFS file-system description object + * @jhead: journal head + * + * This function releases journal head @jhead which was locked by + * the 'make_reservation()' function. It has to be called after each successful + * 'make_reservation()' invocation. + */ +static inline void release_head(struct ubifs_info *c, int jhead) +{ + mutex_unlock(&c->jheads[jhead].wbuf.io_mutex); +} + +/** + * finish_reservation - finish a reservation. + * @c: UBIFS file-system description object + * + * This function finishes journal space reservation. It must be called after + * 'make_reservation()'. + */ +static void finish_reservation(struct ubifs_info *c) +{ + up_read(&c->commit_sem); +} + +/** + * ubifs_get_dent_type - translate VFS inode mode to UBIFS directory entry type. + * @mode: inode mode + */ +int ubifs_get_dent_type(int mode) +{ + switch (mode & S_IFMT) { + case S_IFREG: + return UBIFS_ITYPE_REG; + case S_IFDIR: + return UBIFS_ITYPE_DIR; + case S_IFLNK: + return UBIFS_ITYPE_LNK; + case S_IFBLK: + return UBIFS_ITYPE_BLK; + case S_IFCHR: + return UBIFS_ITYPE_CHR; + case S_IFIFO: + return UBIFS_ITYPE_FIFO; + case S_IFSOCK: + return UBIFS_ITYPE_SOCK; + default: + BUG(); + } + return 0; +} + +static void set_dent_cookie(struct ubifs_info *c, struct ubifs_dent_node *dent) +{ + if (c->double_hash) + dent->cookie = (__force __le32) get_random_u32(); + else + dent->cookie = 0; +} + +/** + * pack_inode - pack an ubifs inode node. + * @c: UBIFS file-system description object + * @ino: buffer in which to pack inode node + * @ui: ubifs inode to pack + * @last: indicates the last node of the group + */ +static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino, + const struct ubifs_inode *ui, int last) +{ + const struct inode *inode = &ui->vfs_inode; + int data_len = 0, last_reference = !inode->nlink; + + ino->ch.node_type = UBIFS_INO_NODE; + ino_key_init_flash(c, &ino->key, inode->inum); + ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum); + ino->atime_sec = cpu_to_le64(inode->atime_sec); + ino->atime_nsec = cpu_to_le32(inode->atime_nsec); + ino->ctime_sec = cpu_to_le64(inode->ctime_sec); + ino->ctime_nsec = cpu_to_le32(inode->ctime_nsec); + ino->mtime_sec = cpu_to_le64(inode->mtime_sec); + ino->mtime_nsec = cpu_to_le32(inode->mtime_nsec); + ino->uid = cpu_to_le32(inode->uid); + ino->gid = cpu_to_le32(inode->gid); + ino->mode = cpu_to_le32(inode->mode); + ino->flags = cpu_to_le32(ui->flags); + ino->size = cpu_to_le64(ui->ui_size); + ino->nlink = cpu_to_le32(inode->nlink); + ino->compr_type = cpu_to_le16(ui->compr_type); + ino->data_len = cpu_to_le32(ui->data_len); + ino->xattr_cnt = cpu_to_le32(ui->xattr_cnt); + ino->xattr_size = cpu_to_le32(ui->xattr_size); + ino->xattr_names = cpu_to_le32(ui->xattr_names); + zero_ino_node_unused(ino); + + /* + * Drop the attached data if this is a deletion inode, the data is not + * needed anymore. + */ + if (!last_reference) { + memcpy(ino->data, ui->data, ui->data_len); + data_len = ui->data_len; + } + + ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last); +} + +/** + * ubifs_jnl_update_file - update file. + * @c: UBIFS file-system description object + * @dir_ui: parent ubifs inode + * @nm: directory entry name + * @ui: ubifs inode to update + * + * This function updates an file by writing a directory entry node, the inode + * node itself, and the parent directory inode node to the journal. If the + * @dir_ui and @nm are NULL, only update @ui. + * + * Returns zero on success. In case of failure, a negative error code is + * returned. + */ +int ubifs_jnl_update_file(struct ubifs_info *c, + const struct ubifs_inode *dir_ui, + const struct fscrypt_name *nm, + const struct ubifs_inode *ui) +{ + const struct inode *dir = NULL, *inode = &ui->vfs_inode; + int err, dlen, ilen, len, lnum, ino_offs, dent_offs, dir_ilen; + int aligned_dlen, aligned_ilen; + struct ubifs_dent_node *dent; + struct ubifs_ino_node *ino; + union ubifs_key dent_key, ino_key; + u8 hash_dent[UBIFS_HASH_ARR_SZ]; + u8 hash_ino[UBIFS_HASH_ARR_SZ]; + u8 hash_ino_dir[UBIFS_HASH_ARR_SZ]; + + ubifs_assert(c, (!nm && !dir_ui) || (nm && dir_ui)); + ubifs_assert(c, inode->nlink != 0); + + ilen = UBIFS_INO_NODE_SZ + ui->data_len; + + if (nm) + dlen = UBIFS_DENT_NODE_SZ + fname_len(nm) + 1; + else + dlen = 0; + + if (dir_ui) { + dir = &dir_ui->vfs_inode; + ubifs_assert(c, dir->nlink != 0); + dir_ilen = UBIFS_INO_NODE_SZ + dir_ui->data_len; + } else + dir_ilen = 0; + + aligned_dlen = ALIGN(dlen, 8); + aligned_ilen = ALIGN(ilen, 8); + len = aligned_dlen + aligned_ilen + dir_ilen; + if (ubifs_authenticated(c)) + len += ALIGN(dir_ilen, 8) + ubifs_auth_node_sz(c); + + dent = kzalloc(len, GFP_NOFS); + if (!dent) + return -ENOMEM; + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, BASEHD, len); + if (err) + goto out_free; + + if (nm) { + dent->ch.node_type = UBIFS_DENT_NODE; + dent_key_init(c, &dent_key, dir->inum, nm); + + key_write(c, &dent_key, dent->key); + dent->inum = cpu_to_le64(inode->inum); + dent->type = ubifs_get_dent_type(inode->mode); + dent->nlen = cpu_to_le16(fname_len(nm)); + memcpy(dent->name, fname_name(nm), fname_len(nm)); + dent->name[fname_len(nm)] = '\0'; + set_dent_cookie(c, dent); + + zero_dent_node_unused(dent); + ubifs_prep_grp_node(c, dent, dlen, 0); + err = ubifs_node_calc_hash(c, dent, hash_dent); + if (err) + goto out_release; + } + + ino = (void *)dent + aligned_dlen; + pack_inode(c, ino, ui, dir_ui == NULL ? 1 : 0); + err = ubifs_node_calc_hash(c, ino, hash_ino); + if (err) + goto out_release; + + if (dir_ui) { + ino = (void *)ino + aligned_ilen; + pack_inode(c, ino, dir_ui, 1); + err = ubifs_node_calc_hash(c, ino, hash_ino_dir); + if (err) + goto out_release; + } + + err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, 0); + if (err) + goto out_release; + release_head(c, BASEHD); + kfree(dent); + ubifs_add_auth_dirt(c, lnum); + + if (nm) { + err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, + hash_dent, nm); + if (err) { + ubifs_assert(c, !get_failure_reason_callback(c)); + goto out_ro; + } + } + + ino_key_init(c, &ino_key, inode->inum); + ino_offs = dent_offs + aligned_dlen; + err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen, hash_ino); + if (err) { + ubifs_assert(c, !get_failure_reason_callback(c)); + goto out_ro; + } + + if (dir_ui) { + ino_key_init(c, &ino_key, dir->inum); + ino_offs += aligned_ilen; + err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, dir_ilen, + hash_ino_dir); + if (err) { + ubifs_assert(c, !get_failure_reason_callback(c)); + goto out_ro; + } + } + + finish_reservation(c); + return 0; + +out_free: + kfree(dent); + return err; + +out_release: + release_head(c, BASEHD); + kfree(dent); +out_ro: + ubifs_ro_mode(c, err); + finish_reservation(c); + return err; +} diff --git a/ubifs-utils/libubifs/key.h b/ubifs-utils/libubifs/key.h new file mode 100644 index 0000000..0a35c6b --- /dev/null +++ b/ubifs-utils/libubifs/key.h @@ -0,0 +1,492 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This header contains various key-related definitions and helper function. + * UBIFS allows several key schemes, so we access key fields only via these + * helpers. At the moment only one key scheme is supported. + * + * Simple key scheme + * ~~~~~~~~~~~~~~~~~ + * + * Keys are 64-bits long. First 32-bits are inode number (parent inode number + * in case of direntry key). Next 3 bits are node type. The last 29 bits are + * 4KiB offset in case of inode node, and direntry hash in case of a direntry + * node. We use "r5" hash borrowed from reiserfs. + */ + +/* + * Lot's of the key helpers require a struct ubifs_info *c as the first parameter. + * But we are not using it at all currently. That's designed for future extensions of + * different c->key_format. But right now, there is only one key type, UBIFS_SIMPLE_KEY_FMT. + */ + +#ifndef __UBIFS_KEY_H__ +#define __UBIFS_KEY_H__ + +/** + * key_mask_hash - mask a valid hash value. + * @val: value to be masked + * + * We use hash values as offset in directories, so values %0 and %1 are + * reserved for "." and "..". %2 is reserved for "end of readdir" marker. This + * function makes sure the reserved values are not used. + */ +static inline uint32_t key_mask_hash(uint32_t hash) +{ + hash &= UBIFS_S_KEY_HASH_MASK; + if (unlikely(hash <= 2)) + hash += 3; + return hash; +} + +/** + * key_r5_hash - R5 hash function (borrowed from reiserfs). + * @s: direntry name + * @len: name length + */ +static inline uint32_t key_r5_hash(const char *s, int len) +{ + uint32_t a = 0; + const signed char *str = (const signed char *)s; + + while (len--) { + a += *str << 4; + a += *str >> 4; + a *= 11; + str++; + } + + return key_mask_hash(a); +} + +/** + * key_test_hash - testing hash function. + * @str: direntry name + * @len: name length + */ +static inline uint32_t key_test_hash(const char *str, int len) +{ + uint32_t a = 0; + + len = min_t(uint32_t, len, 4); + memcpy(&a, str, len); + return key_mask_hash(a); +} + +/** + * ino_key_init - initialize inode key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + */ +static inline void ino_key_init(__unused const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * ino_key_init_flash - initialize on-flash inode key. + * @c: UBIFS file-system description object + * @k: key to initialize + * @inum: inode number + */ +static inline void ino_key_init_flash(__unused const struct ubifs_info *c, + void *k, ino_t inum) +{ + union ubifs_key *key = k; + + key->j32[0] = cpu_to_le32(inum); + key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS); + memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8); +} + +/** + * lowest_ino_key - get the lowest possible inode key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + */ +static inline void lowest_ino_key(__unused const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = 0; +} + +/** + * highest_ino_key - get the highest possible inode key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + */ +static inline void highest_ino_key(__unused const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = 0xffffffff; +} + +/** + * dent_key_init - initialize directory entry key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: parent inode number + * @nm: direntry name and length. Not a string when encrypted! + */ +static inline void dent_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + const struct fscrypt_name *nm) +{ + uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm)); + + ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->u32[0] = inum; + key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS); +} + +/** + * dent_key_init_hash - initialize directory entry key without re-calculating + * hash function. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: parent inode number + * @hash: direntry name hash + */ +static inline void dent_key_init_hash(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + uint32_t hash) +{ + ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->u32[0] = inum; + key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS); +} + +/** + * xent_key_init - initialize extended attribute entry key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: host inode number + * @nm: extended attribute entry name and length + */ +static inline void xent_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + const struct fscrypt_name *nm) +{ + uint32_t hash = c->key_hash(fname_name(nm), fname_len(nm)); + + ubifs_assert(c, !(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->u32[0] = inum; + key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS); +} + +/** + * lowest_xent_key - get the lowest possible extended attribute entry key. + * @c: UBIFS file-system description object + * @key: where to store the lowest key + * @inum: host inode number + */ +static inline void lowest_xent_key(__unused const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS; +} + +/** + * data_key_init - initialize data key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + * @block: block number + */ +static inline void data_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + unsigned int block) +{ + ubifs_assert(c, !(block & ~UBIFS_S_KEY_BLOCK_MASK)); + key->u32[0] = inum; + key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS); +} + +/** + * highest_data_key - get the highest possible data key for an inode. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + */ +static inline void highest_data_key(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + data_key_init(c, key, inum, UBIFS_S_KEY_BLOCK_MASK); +} + +/** + * trun_key_init - initialize truncation node key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + * + * Note, UBIFS does not have truncation keys on the media and this function is + * only used for purposes of replay. + */ +static inline void trun_key_init(__unused const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * invalid_key_init - initialize invalid node key. + * @c: UBIFS file-system description object + * @key: key to initialize + * + * This is a helper function which marks a @key object as invalid. + */ +static inline void invalid_key_init(__unused const struct ubifs_info *c, + union ubifs_key *key) +{ + key->u32[0] = 0xDEADBEAF; + key->u32[1] = UBIFS_INVALID_KEY; +} + +/** + * key_type - get key type. + * @c: UBIFS file-system description object + * @key: key to get type of + */ +static inline int key_type(__unused const struct ubifs_info *c, + const union ubifs_key *key) +{ + return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * key_type_flash - get type of a on-flash formatted key. + * @c: UBIFS file-system description object + * @k: key to get type of + */ +static inline int key_type_flash(__unused const struct ubifs_info *c, + const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * key_inum - fetch inode number from key. + * @c: UBIFS file-system description object + * @k: key to fetch inode number from + */ +static inline ino_t key_inum(__unused const struct ubifs_info *c, const void *k) +{ + const union ubifs_key *key = k; + + return key->u32[0]; +} + +/** + * key_inum_flash - fetch inode number from an on-flash formatted key. + * @c: UBIFS file-system description object + * @k: key to fetch inode number from + */ +static inline ino_t key_inum_flash(__unused const struct ubifs_info *c, + const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[0]); +} + +/** + * key_hash - get directory entry hash. + * @c: UBIFS file-system description object + * @key: the key to get hash from + */ +static inline uint32_t key_hash(__unused const struct ubifs_info *c, + const union ubifs_key *key) +{ + return key->u32[1] & UBIFS_S_KEY_HASH_MASK; +} + +/** + * key_hash_flash - get directory entry hash from an on-flash formatted key. + * @c: UBIFS file-system description object + * @k: the key to get hash from + */ +static inline uint32_t key_hash_flash(__unused const struct ubifs_info *c, + const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK; +} + +/** + * key_block - get data block number. + * @c: UBIFS file-system description object + * @key: the key to get the block number from + */ +static inline unsigned int key_block(__unused const struct ubifs_info *c, + const union ubifs_key *key) +{ + return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK; +} + +/** + * key_block_flash - get data block number from an on-flash formatted key. + * @c: UBIFS file-system description object + * @k: the key to get the block number from + */ +static inline unsigned int key_block_flash(__unused const struct ubifs_info *c, + const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK; +} + +/** + * key_read - transform a key to in-memory format. + * @c: UBIFS file-system description object + * @from: the key to transform + * @to: the key to store the result + */ +static inline void key_read(__unused const struct ubifs_info *c, + const void *from, union ubifs_key *to) +{ + const union ubifs_key *f = from; + + to->u32[0] = le32_to_cpu(f->j32[0]); + to->u32[1] = le32_to_cpu(f->j32[1]); +} + +/** + * key_write - transform a key from in-memory format. + * @c: UBIFS file-system description object + * @from: the key to transform + * @to: the key to store the result + */ +static inline void key_write(__unused const struct ubifs_info *c, + const union ubifs_key *from, void *to) +{ + union ubifs_key *t = to; + + t->j32[0] = cpu_to_le32(from->u32[0]); + t->j32[1] = cpu_to_le32(from->u32[1]); + memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8); +} + +/** + * key_write_idx - transform a key from in-memory format for the index. + * @c: UBIFS file-system description object + * @from: the key to transform + * @to: the key to store the result + */ +static inline void key_write_idx(__unused const struct ubifs_info *c, + const union ubifs_key *from, void *to) +{ + union ubifs_key *t = to; + + t->j32[0] = cpu_to_le32(from->u32[0]); + t->j32[1] = cpu_to_le32(from->u32[1]); +} + +/** + * key_copy - copy a key. + * @c: UBIFS file-system description object + * @from: the key to copy from + * @to: the key to copy to + */ +static inline void key_copy(__unused const struct ubifs_info *c, + const union ubifs_key *from, union ubifs_key *to) +{ + to->u64[0] = from->u64[0]; +} + +/** + * keys_cmp - compare keys. + * @c: UBIFS file-system description object + * @key1: the first key to compare + * @key2: the second key to compare + * + * This function compares 2 keys and returns %-1 if @key1 is less than + * @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2. + */ +static inline int keys_cmp(__unused const struct ubifs_info *c, + const union ubifs_key *key1, + const union ubifs_key *key2) +{ + if (key1->u32[0] < key2->u32[0]) + return -1; + if (key1->u32[0] > key2->u32[0]) + return 1; + if (key1->u32[1] < key2->u32[1]) + return -1; + if (key1->u32[1] > key2->u32[1]) + return 1; + + return 0; +} + +/** + * keys_eq - determine if keys are equivalent. + * @c: UBIFS file-system description object + * @key1: the first key to compare + * @key2: the second key to compare + * + * This function compares 2 keys and returns %1 if @key1 is equal to @key2 and + * %0 if not. + */ +static inline int keys_eq(__unused const struct ubifs_info *c, + const union ubifs_key *key1, + const union ubifs_key *key2) +{ + if (key1->u32[0] != key2->u32[0]) + return 0; + if (key1->u32[1] != key2->u32[1]) + return 0; + return 1; +} + +/** + * is_hash_key - is a key vulnerable to hash collisions. + * @c: UBIFS file-system description object + * @key: key + * + * This function returns %1 if @key is a hashed key or %0 otherwise. + */ +static inline int is_hash_key(const struct ubifs_info *c, + const union ubifs_key *key) +{ + int type = key_type(c, key); + + return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY; +} + +/** + * key_max_inode_size - get maximum file size allowed by current key format. + * @c: UBIFS file-system description object + */ +static inline unsigned long long key_max_inode_size(const struct ubifs_info *c) +{ + switch (c->key_fmt) { + case UBIFS_SIMPLE_KEY_FMT: + return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE; + default: + return 0; + } +} + +#endif /* !__UBIFS_KEY_H__ */ diff --git a/ubifs-utils/libubifs/log.c b/ubifs-utils/libubifs/log.c new file mode 100644 index 0000000..c3dfd98 --- /dev/null +++ b/ubifs-utils/libubifs/log.c @@ -0,0 +1,750 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file is a part of UBIFS journal implementation and contains various + * functions which manipulate the log. The log is a fixed area on the flash + * which does not contain any data but refers to buds. The log is a part of the + * journal. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "misc.h" + +static int dbg_check_bud_bytes(struct ubifs_info *c); + +/** + * ubifs_search_bud - search bud LEB. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number to search + * + * This function searches bud LEB @lnum. Returns bud description object in case + * of success and %NULL if there is no bud with this LEB number. + */ +struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum) +{ + struct rb_node *p; + struct ubifs_bud *bud; + + spin_lock(&c->buds_lock); + p = c->buds.rb_node; + while (p) { + bud = rb_entry(p, struct ubifs_bud, rb); + if (lnum < bud->lnum) + p = p->rb_left; + else if (lnum > bud->lnum) + p = p->rb_right; + else { + spin_unlock(&c->buds_lock); + return bud; + } + } + spin_unlock(&c->buds_lock); + return NULL; +} + +/** + * ubifs_get_wbuf - get the wbuf associated with a LEB, if there is one. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number to search + * + * This functions returns the wbuf for @lnum or %NULL if there is not one. + */ +struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum) +{ + struct rb_node *p; + struct ubifs_bud *bud; + int jhead; + + if (!c->jheads) + return NULL; + + spin_lock(&c->buds_lock); + p = c->buds.rb_node; + while (p) { + bud = rb_entry(p, struct ubifs_bud, rb); + if (lnum < bud->lnum) + p = p->rb_left; + else if (lnum > bud->lnum) + p = p->rb_right; + else { + jhead = bud->jhead; + spin_unlock(&c->buds_lock); + return &c->jheads[jhead].wbuf; + } + } + spin_unlock(&c->buds_lock); + return NULL; +} + +/** + * empty_log_bytes - calculate amount of empty space in the log. + * @c: UBIFS file-system description object + */ +static inline long long empty_log_bytes(const struct ubifs_info *c) +{ + long long h, t; + + h = (long long)c->lhead_lnum * c->leb_size + c->lhead_offs; + t = (long long)c->ltail_lnum * c->leb_size; + + if (h > t) + return c->log_bytes - h + t; + else if (h != t) + return t - h; + else if (c->lhead_lnum != c->ltail_lnum) + return 0; + else + return c->log_bytes; +} + +/** + * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list. + * @c: UBIFS file-system description object + * @bud: the bud to add + */ +void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud) +{ + struct rb_node **p, *parent = NULL; + struct ubifs_bud *b; + struct ubifs_jhead *jhead; + + spin_lock(&c->buds_lock); + p = &c->buds.rb_node; + while (*p) { + parent = *p; + b = rb_entry(parent, struct ubifs_bud, rb); + ubifs_assert(c, bud->lnum != b->lnum); + if (bud->lnum < b->lnum) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + rb_link_node(&bud->rb, parent, p); + rb_insert_color(&bud->rb, &c->buds); + if (c->jheads) { + jhead = &c->jheads[bud->jhead]; + list_add_tail(&bud->list, &jhead->buds_list); + } else + ubifs_assert(c, c->replaying && c->ro_mount); + + /* + * Note, although this is a new bud, we anyway account this space now, + * before any data has been written to it, because this is about to + * guarantee fixed mount time, and this bud will anyway be read and + * scanned. + */ + c->bud_bytes += c->leb_size - bud->start; + + dbg_log("LEB %d:%d, jhead %s, bud_bytes %lld", bud->lnum, + bud->start, dbg_jhead(bud->jhead), c->bud_bytes); + spin_unlock(&c->buds_lock); +} + +/** + * ubifs_add_bud_to_log - add a new bud to the log. + * @c: UBIFS file-system description object + * @jhead: journal head the bud belongs to + * @lnum: LEB number of the bud + * @offs: starting offset of the bud + * + * This function writes a reference node for the new bud LEB @lnum to the log, + * and adds it to the buds trees. It also makes sure that log size does not + * exceed the 'c->max_bud_bytes' limit. Returns zero in case of success, + * %-EAGAIN if commit is required, and a negative error code in case of + * failure. + */ +int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs) +{ + int err; + struct ubifs_bud *bud; + struct ubifs_ref_node *ref; + + bud = kmalloc(sizeof(struct ubifs_bud), GFP_NOFS); + if (!bud) + return -ENOMEM; + ref = kzalloc(c->ref_node_alsz, GFP_NOFS); + if (!ref) { + kfree(bud); + return -ENOMEM; + } + + mutex_lock(&c->log_mutex); + ubifs_assert(c, !c->ro_media && !c->ro_mount); + if (c->ro_error) { + err = -EROFS; + goto out_unlock; + } + + /* Make sure we have enough space in the log */ + if (empty_log_bytes(c) - c->ref_node_alsz < c->min_log_bytes) { + dbg_log("not enough log space - %lld, required %d", + empty_log_bytes(c), c->min_log_bytes); + ubifs_commit_required(c); + err = -EAGAIN; + goto out_unlock; + } + + /* + * Make sure the amount of space in buds will not exceed the + * 'c->max_bud_bytes' limit, because we want to guarantee mount time + * limits. + * + * It is not necessary to hold @c->buds_lock when reading @c->bud_bytes + * because we are holding @c->log_mutex. All @c->bud_bytes take place + * when both @c->log_mutex and @c->bud_bytes are locked. + */ + if (c->bud_bytes + c->leb_size - offs > c->max_bud_bytes) { + dbg_log("bud bytes %lld (%lld max), require commit", + c->bud_bytes, c->max_bud_bytes); + ubifs_commit_required(c); + err = -EAGAIN; + goto out_unlock; + } + + /* + * If the journal is full enough - start background commit. Note, it is + * OK to read 'c->cmt_state' without spinlock because integer reads + * are atomic in the kernel. + */ + if (c->bud_bytes >= c->bg_bud_bytes && + c->cmt_state == COMMIT_RESTING) { + dbg_log("bud bytes %lld (%lld max), initiate BG commit", + c->bud_bytes, c->max_bud_bytes); + ubifs_request_bg_commit(c); + } + + bud->lnum = lnum; + bud->start = offs; + bud->jhead = jhead; + bud->log_hash = NULL; + + ref->ch.node_type = UBIFS_REF_NODE; + ref->lnum = cpu_to_le32(bud->lnum); + ref->offs = cpu_to_le32(bud->start); + ref->jhead = cpu_to_le32(jhead); + + if (c->lhead_offs > c->leb_size - c->ref_node_alsz) { + c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); + ubifs_assert(c, c->lhead_lnum != c->ltail_lnum); + c->lhead_offs = 0; + } + + if (c->lhead_offs == 0) { + /* Must ensure next log LEB has been unmapped */ + err = ubifs_leb_unmap(c, c->lhead_lnum); + if (err) + goto out_unlock; + } + + if (bud->start == 0) { + /* + * Before writing the LEB reference which refers an empty LEB + * to the log, we have to make sure it is mapped, because + * otherwise we'd risk to refer an LEB with garbage in case of + * an unclean reboot, because the target LEB might have been + * unmapped, but not yet physically erased. + */ + err = ubifs_leb_map(c, bud->lnum); + if (err) + goto out_unlock; + } + + dbg_log("write ref LEB %d:%d", + c->lhead_lnum, c->lhead_offs); + err = ubifs_write_node(c, ref, UBIFS_REF_NODE_SZ, c->lhead_lnum, + c->lhead_offs); + if (err) + goto out_unlock; + + err = ubifs_shash_update(c, c->log_hash, ref, UBIFS_REF_NODE_SZ); + if (err) + goto out_unlock; + + err = ubifs_shash_copy_state(c, c->log_hash, c->jheads[jhead].log_hash); + if (err) + goto out_unlock; + + c->lhead_offs += c->ref_node_alsz; + + ubifs_add_bud(c, bud); + + mutex_unlock(&c->log_mutex); + kfree(ref); + return 0; + +out_unlock: + mutex_unlock(&c->log_mutex); + kfree(ref); + kfree(bud); + return err; +} + +/** + * remove_buds - remove used buds. + * @c: UBIFS file-system description object + * + * This function removes use buds from the buds tree. It does not remove the + * buds which are pointed to by journal heads. + */ +static void remove_buds(struct ubifs_info *c) +{ + struct rb_node *p; + + ubifs_assert(c, list_empty(&c->old_buds)); + c->cmt_bud_bytes = 0; + spin_lock(&c->buds_lock); + p = rb_first(&c->buds); + while (p) { + struct rb_node *p1 = p; + struct ubifs_bud *bud; + struct ubifs_wbuf *wbuf; + + p = rb_next(p); + bud = rb_entry(p1, struct ubifs_bud, rb); + wbuf = &c->jheads[bud->jhead].wbuf; + + if (wbuf->lnum == bud->lnum) { + /* + * Do not remove buds which are pointed to by journal + * heads (non-closed buds). + */ + c->cmt_bud_bytes += wbuf->offs - bud->start; + dbg_log("preserve %d:%d, jhead %s, bud bytes %d, cmt_bud_bytes %lld", + bud->lnum, bud->start, dbg_jhead(bud->jhead), + wbuf->offs - bud->start, c->cmt_bud_bytes); + bud->start = wbuf->offs; + } else { + c->cmt_bud_bytes += c->leb_size - bud->start; + dbg_log("remove %d:%d, jhead %s, bud bytes %d, cmt_bud_bytes %lld", + bud->lnum, bud->start, dbg_jhead(bud->jhead), + c->leb_size - bud->start, c->cmt_bud_bytes); + rb_erase(p1, &c->buds); + /* + * If the commit does not finish, the recovery will need + * to replay the journal, in which case the old buds + * must be unchanged. Do not release them until post + * commit i.e. do not allow them to be garbage + * collected. + */ + list_move(&bud->list, &c->old_buds); + } + } + spin_unlock(&c->buds_lock); +} + +/** + * ubifs_log_start_commit - start commit. + * @c: UBIFS file-system description object + * @ltail_lnum: return new log tail LEB number + * + * The commit operation starts with writing "commit start" node to the log and + * reference nodes for all journal heads which will define new journal after + * the commit has been finished. The commit start and reference nodes are + * written in one go to the nearest empty log LEB (hence, when commit is + * finished UBIFS may safely unmap all the previous log LEBs). This function + * returns zero in case of success and a negative error code in case of + * failure. + */ +int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum) +{ + void *buf; + struct ubifs_cs_node *cs; + struct ubifs_ref_node *ref; + int err, i, max_len, len; + + err = dbg_check_bud_bytes(c); + if (err) + return err; + + max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ; + max_len = ALIGN(max_len, c->min_io_size); + buf = cs = kmalloc(max_len, GFP_NOFS); + if (!buf) + return -ENOMEM; + + cs->ch.node_type = UBIFS_CS_NODE; + cs->cmt_no = cpu_to_le64(c->cmt_no); + ubifs_prepare_node(c, cs, UBIFS_CS_NODE_SZ, 0); + + err = ubifs_shash_init(c, c->log_hash); + if (err) + goto out; + + err = ubifs_shash_update(c, c->log_hash, cs, UBIFS_CS_NODE_SZ); + if (err < 0) + goto out; + + /* + * Note, we do not lock 'c->log_mutex' because this is the commit start + * phase and we are exclusively using the log. And we do not lock + * write-buffer because nobody can write to the file-system at this + * phase. + */ + + len = UBIFS_CS_NODE_SZ; + for (i = 0; i < c->jhead_cnt; i++) { + int lnum = c->jheads[i].wbuf.lnum; + int offs = c->jheads[i].wbuf.offs; + + if (lnum == -1 || offs == c->leb_size) + continue; + + dbg_log("add ref to LEB %d:%d for jhead %s", + lnum, offs, dbg_jhead(i)); + ref = buf + len; + ref->ch.node_type = UBIFS_REF_NODE; + ref->lnum = cpu_to_le32(lnum); + ref->offs = cpu_to_le32(offs); + ref->jhead = cpu_to_le32(i); + + ubifs_prepare_node(c, ref, UBIFS_REF_NODE_SZ, 0); + len += UBIFS_REF_NODE_SZ; + + err = ubifs_shash_update(c, c->log_hash, ref, + UBIFS_REF_NODE_SZ); + if (err) + goto out; + ubifs_shash_copy_state(c, c->log_hash, c->jheads[i].log_hash); + } + + ubifs_pad(c, buf + len, ALIGN(len, c->min_io_size) - len); + + /* Switch to the next log LEB */ + if (c->lhead_offs) { + c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); + ubifs_assert(c, c->lhead_lnum != c->ltail_lnum); + c->lhead_offs = 0; + } + + /* Must ensure next LEB has been unmapped */ + err = ubifs_leb_unmap(c, c->lhead_lnum); + if (err) + goto out; + + len = ALIGN(len, c->min_io_size); + dbg_log("writing commit start at LEB %d:0, len %d", c->lhead_lnum, len); + err = ubifs_leb_write(c, c->lhead_lnum, cs, 0, len); + if (err) + goto out; + + *ltail_lnum = c->lhead_lnum; + + c->lhead_offs += len; + ubifs_assert(c, c->lhead_offs < c->leb_size); + + remove_buds(c); + + /* + * We have started the commit and now users may use the rest of the log + * for new writes. + */ + c->min_log_bytes = 0; + +out: + kfree(buf); + return err; +} + +/** + * ubifs_log_end_commit - end commit. + * @c: UBIFS file-system description object + * @ltail_lnum: new log tail LEB number + * + * This function is called on when the commit operation was finished. It + * moves log tail to new position and updates the master node so that it stores + * the new log tail LEB number. Returns zero in case of success and a negative + * error code in case of failure. + */ +int ubifs_log_end_commit(struct ubifs_info *c, int ltail_lnum) +{ + int err; + + /* + * At this phase we have to lock 'c->log_mutex' because UBIFS allows FS + * writes during commit. Its only short "commit" start phase when + * writers are blocked. + */ + mutex_lock(&c->log_mutex); + + dbg_log("old tail was LEB %d:0, new tail is LEB %d:0", + c->ltail_lnum, ltail_lnum); + + c->ltail_lnum = ltail_lnum; + /* + * The commit is finished and from now on it must be guaranteed that + * there is always enough space for the next commit. + */ + c->min_log_bytes = c->leb_size; + + spin_lock(&c->buds_lock); + c->bud_bytes -= c->cmt_bud_bytes; + spin_unlock(&c->buds_lock); + + err = dbg_check_bud_bytes(c); + if (err) + goto out; + + err = ubifs_write_master(c); + +out: + mutex_unlock(&c->log_mutex); + return err; +} + +/** + * ubifs_log_post_commit - things to do after commit is completed. + * @c: UBIFS file-system description object + * @old_ltail_lnum: old log tail LEB number + * + * Release buds only after commit is completed, because they must be unchanged + * if recovery is needed. + * + * Unmap log LEBs only after commit is completed, because they may be needed for + * recovery. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum) +{ + int lnum, err = 0; + + while (!list_empty(&c->old_buds)) { + struct ubifs_bud *bud; + + bud = list_entry(c->old_buds.next, struct ubifs_bud, list); + err = ubifs_return_leb(c, bud->lnum); + if (err) + return err; + list_del(&bud->list); + kfree(bud->log_hash); + kfree(bud); + } + mutex_lock(&c->log_mutex); + for (lnum = old_ltail_lnum; lnum != c->ltail_lnum; + lnum = ubifs_next_log_lnum(c, lnum)) { + dbg_log("unmap log LEB %d", lnum); + err = ubifs_leb_unmap(c, lnum); + if (err) + goto out; + } +out: + mutex_unlock(&c->log_mutex); + return err; +} + +/** + * struct done_ref - references that have been done. + * @rb: rb-tree node + * @lnum: LEB number + */ +struct done_ref { + struct rb_node rb; + int lnum; +}; + +/** + * done_already - determine if a reference has been done already. + * @done_tree: rb-tree to store references that have been done + * @lnum: LEB number of reference + * + * This function returns %1 if the reference has been done, %0 if not, otherwise + * a negative error code is returned. + */ +static int done_already(struct rb_root *done_tree, int lnum) +{ + struct rb_node **p = &done_tree->rb_node, *parent = NULL; + struct done_ref *dr; + + while (*p) { + parent = *p; + dr = rb_entry(parent, struct done_ref, rb); + if (lnum < dr->lnum) + p = &(*p)->rb_left; + else if (lnum > dr->lnum) + p = &(*p)->rb_right; + else + return 1; + } + + dr = kzalloc(sizeof(struct done_ref), GFP_NOFS); + if (!dr) + return -ENOMEM; + + dr->lnum = lnum; + + rb_link_node(&dr->rb, parent, p); + rb_insert_color(&dr->rb, done_tree); + + return 0; +} + +/** + * destroy_done_tree - destroy the done tree. + * @done_tree: done tree to destroy + */ +static void destroy_done_tree(struct rb_root *done_tree) +{ + struct done_ref *dr, *n; + + rbtree_postorder_for_each_entry_safe(dr, n, done_tree, rb) + kfree(dr); +} + +/** + * add_node - add a node to the consolidated log. + * @c: UBIFS file-system description object + * @buf: buffer to which to add + * @lnum: LEB number to which to write is passed and returned here + * @offs: offset to where to write is passed and returned here + * @node: node to add + * + * This function returns %0 on success and a negative error code on failure. + */ +static int add_node(struct ubifs_info *c, void *buf, int *lnum, int *offs, + void *node) +{ + struct ubifs_ch *ch = node; + int len = le32_to_cpu(ch->len), remains = c->leb_size - *offs; + + if (len > remains) { + int sz = ALIGN(*offs, c->min_io_size), err; + + ubifs_pad(c, buf + *offs, sz - *offs); + err = ubifs_leb_change(c, *lnum, buf, sz); + if (err) + return err; + *lnum = ubifs_next_log_lnum(c, *lnum); + *offs = 0; + } + memcpy(buf + *offs, node, len); + *offs += ALIGN(len, 8); + return 0; +} + +/** + * ubifs_consolidate_log - consolidate the log. + * @c: UBIFS file-system description object + * + * Repeated failed commits could cause the log to be full, but at least 1 LEB is + * needed for commit. This function rewrites the reference nodes in the log + * omitting duplicates, and failed CS nodes, and leaving no gaps. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_consolidate_log(struct ubifs_info *c) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + struct rb_root done_tree = RB_ROOT; + int lnum, err, first = 1, write_lnum, offs = 0; + void *buf; + + dbg_rcvry("log tail LEB %d, log head LEB %d", c->ltail_lnum, + c->lhead_lnum); + buf = vmalloc(c->leb_size); + if (!buf) + return -ENOMEM; + lnum = c->ltail_lnum; + write_lnum = lnum; + while (1) { + sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0); + if (IS_ERR(sleb)) { + err = PTR_ERR(sleb); + goto out_free; + } + list_for_each_entry(snod, &sleb->nodes, list) { + switch (snod->type) { + case UBIFS_REF_NODE: { + struct ubifs_ref_node *ref = snod->node; + int ref_lnum = le32_to_cpu(ref->lnum); + + err = done_already(&done_tree, ref_lnum); + if (err < 0) + goto out_scan; + if (err != 1) { + err = add_node(c, buf, &write_lnum, + &offs, snod->node); + if (err) + goto out_scan; + } + break; + } + case UBIFS_CS_NODE: + if (!first) + break; + err = add_node(c, buf, &write_lnum, &offs, + snod->node); + if (err) + goto out_scan; + first = 0; + break; + } + } + ubifs_scan_destroy(sleb); + if (lnum == c->lhead_lnum) + break; + lnum = ubifs_next_log_lnum(c, lnum); + } + if (offs) { + int sz = ALIGN(offs, c->min_io_size); + + ubifs_pad(c, buf + offs, sz - offs); + err = ubifs_leb_change(c, write_lnum, buf, sz); + if (err) + goto out_free; + offs = ALIGN(offs, c->min_io_size); + } + destroy_done_tree(&done_tree); + vfree(buf); + if (write_lnum == c->lhead_lnum) { + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "log is too full"); + return -EINVAL; + } + /* Unmap remaining LEBs */ + lnum = write_lnum; + do { + lnum = ubifs_next_log_lnum(c, lnum); + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } while (lnum != c->lhead_lnum); + c->lhead_lnum = write_lnum; + c->lhead_offs = offs; + dbg_rcvry("new log head at %d:%d", c->lhead_lnum, c->lhead_offs); + return 0; + +out_scan: + ubifs_scan_destroy(sleb); +out_free: + destroy_done_tree(&done_tree); + vfree(buf); + return err; +} + +/** + * dbg_check_bud_bytes - make sure bud bytes calculation are all right. + * @c: UBIFS file-system description object + * + * This function makes sure the amount of flash space used by closed buds + * ('c->bud_bytes' is correct). Returns zero in case of success and %-EINVAL in + * case of failure. + */ +static int dbg_check_bud_bytes(__unused struct ubifs_info *c) +{ + return 0; +} diff --git a/ubifs-utils/libubifs/lprops.c b/ubifs-utils/libubifs/lprops.c new file mode 100644 index 0000000..a7a2305 --- /dev/null +++ b/ubifs-utils/libubifs/lprops.c @@ -0,0 +1,864 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the functions that access LEB properties and their + * categories. LEBs are categorized based on the needs of UBIFS, and the + * categories are stored as either heaps or lists to provide a fast way of + * finding a LEB in a particular category. For example, UBIFS may need to find + * an empty LEB for the journal, or a very dirty LEB for garbage collection. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "misc.h" + +/** + * get_heap_comp_val - get the LEB properties value for heap comparisons. + * @lprops: LEB properties + * @cat: LEB category + */ +static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat) +{ + switch (cat) { + case LPROPS_FREE: + return lprops->free; + case LPROPS_DIRTY_IDX: + return lprops->free + lprops->dirty; + default: + return lprops->dirty; + } +} + +/** + * move_up_lpt_heap - move a new heap entry up as far as possible. + * @c: UBIFS file-system description object + * @heap: LEB category heap + * @lprops: LEB properties to move + * @cat: LEB category + * + * New entries to a heap are added at the bottom and then moved up until the + * parent's value is greater. In the case of LPT's category heaps, the value + * is either the amount of free space or the amount of dirty space, depending + * on the category. + */ +static void move_up_lpt_heap(__unused struct ubifs_info *c, + struct ubifs_lpt_heap *heap, + struct ubifs_lprops *lprops, int cat) +{ + int val1, val2, hpos; + + hpos = lprops->hpos; + if (!hpos) + return; /* Already top of the heap */ + val1 = get_heap_comp_val(lprops, cat); + /* Compare to parent and, if greater, move up the heap */ + do { + int ppos = (hpos - 1) / 2; + + val2 = get_heap_comp_val(heap->arr[ppos], cat); + if (val2 >= val1) + return; + /* Greater than parent so move up */ + heap->arr[ppos]->hpos = hpos; + heap->arr[hpos] = heap->arr[ppos]; + heap->arr[ppos] = lprops; + lprops->hpos = ppos; + hpos = ppos; + } while (hpos); +} + +/** + * adjust_lpt_heap - move a changed heap entry up or down the heap. + * @c: UBIFS file-system description object + * @heap: LEB category heap + * @lprops: LEB properties to move + * @hpos: heap position of @lprops + * @cat: LEB category + * + * Changed entries in a heap are moved up or down until the parent's value is + * greater. In the case of LPT's category heaps, the value is either the amount + * of free space or the amount of dirty space, depending on the category. + */ +static void adjust_lpt_heap(__unused struct ubifs_info *c, + struct ubifs_lpt_heap *heap, + struct ubifs_lprops *lprops, int hpos, int cat) +{ + int val1, val2, val3, cpos; + + val1 = get_heap_comp_val(lprops, cat); + /* Compare to parent and, if greater than parent, move up the heap */ + if (hpos) { + int ppos = (hpos - 1) / 2; + + val2 = get_heap_comp_val(heap->arr[ppos], cat); + if (val1 > val2) { + /* Greater than parent so move up */ + while (1) { + heap->arr[ppos]->hpos = hpos; + heap->arr[hpos] = heap->arr[ppos]; + heap->arr[ppos] = lprops; + lprops->hpos = ppos; + hpos = ppos; + if (!hpos) + return; + ppos = (hpos - 1) / 2; + val2 = get_heap_comp_val(heap->arr[ppos], cat); + if (val1 <= val2) + return; + /* Still greater than parent so keep going */ + } + } + } + + /* Not greater than parent, so compare to children */ + while (1) { + /* Compare to left child */ + cpos = hpos * 2 + 1; + if (cpos >= heap->cnt) + return; + val2 = get_heap_comp_val(heap->arr[cpos], cat); + if (val1 < val2) { + /* Less than left child, so promote biggest child */ + if (cpos + 1 < heap->cnt) { + val3 = get_heap_comp_val(heap->arr[cpos + 1], + cat); + if (val3 > val2) + cpos += 1; /* Right child is bigger */ + } + heap->arr[cpos]->hpos = hpos; + heap->arr[hpos] = heap->arr[cpos]; + heap->arr[cpos] = lprops; + lprops->hpos = cpos; + hpos = cpos; + continue; + } + /* Compare to right child */ + cpos += 1; + if (cpos >= heap->cnt) + return; + val3 = get_heap_comp_val(heap->arr[cpos], cat); + if (val1 < val3) { + /* Less than right child, so promote right child */ + heap->arr[cpos]->hpos = hpos; + heap->arr[hpos] = heap->arr[cpos]; + heap->arr[cpos] = lprops; + lprops->hpos = cpos; + hpos = cpos; + continue; + } + return; + } +} + +/** + * add_to_lpt_heap - add LEB properties to a LEB category heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to add + * @cat: LEB category + * + * This function returns %1 if @lprops is added to the heap for LEB category + * @cat, otherwise %0 is returned because the heap is full. + */ +static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops, + int cat) +{ + struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1]; + + if (heap->cnt >= heap->max_cnt) { + const int b = LPT_HEAP_SZ / 2 - 1; + int cpos, val1, val2; + + /* Compare to some other LEB on the bottom of heap */ + /* Pick a position kind of randomly */ + cpos = (((size_t)lprops >> 4) & b) + b; + ubifs_assert(c, cpos >= b); + ubifs_assert(c, cpos < LPT_HEAP_SZ); + ubifs_assert(c, cpos < heap->cnt); + + val1 = get_heap_comp_val(lprops, cat); + val2 = get_heap_comp_val(heap->arr[cpos], cat); + if (val1 > val2) { + struct ubifs_lprops *lp; + + lp = heap->arr[cpos]; + lp->flags &= ~LPROPS_CAT_MASK; + lp->flags |= LPROPS_UNCAT; + list_add(&lp->list, &c->uncat_list); + lprops->hpos = cpos; + heap->arr[cpos] = lprops; + move_up_lpt_heap(c, heap, lprops, cat); + return 1; /* Added to heap */ + } + return 0; /* Not added to heap */ + } else { + lprops->hpos = heap->cnt++; + heap->arr[lprops->hpos] = lprops; + move_up_lpt_heap(c, heap, lprops, cat); + return 1; /* Added to heap */ + } +} + +/** + * remove_from_lpt_heap - remove LEB properties from a LEB category heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to remove + * @cat: LEB category + */ +static void remove_from_lpt_heap(struct ubifs_info *c, + struct ubifs_lprops *lprops, int cat) +{ + struct ubifs_lpt_heap *heap; + int hpos = lprops->hpos; + + heap = &c->lpt_heap[cat - 1]; + ubifs_assert(c, hpos >= 0 && hpos < heap->cnt); + ubifs_assert(c, heap->arr[hpos] == lprops); + heap->cnt -= 1; + if (hpos < heap->cnt) { + heap->arr[hpos] = heap->arr[heap->cnt]; + heap->arr[hpos]->hpos = hpos; + adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat); + } +} + +/** + * lpt_heap_replace - replace lprops in a category heap. + * @c: UBIFS file-system description object + * @new_lprops: LEB properties with which to replace + * @cat: LEB category + * + * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode) + * and the lprops that the pnode contains. When that happens, references in + * the category heaps to those lprops must be updated to point to the new + * lprops. This function does that. + */ +static void lpt_heap_replace(struct ubifs_info *c, + struct ubifs_lprops *new_lprops, int cat) +{ + struct ubifs_lpt_heap *heap; + int hpos = new_lprops->hpos; + + heap = &c->lpt_heap[cat - 1]; + heap->arr[hpos] = new_lprops; +} + +/** + * ubifs_add_to_cat - add LEB properties to a category list or heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to add + * @cat: LEB category to which to add + * + * LEB properties are categorized to enable fast find operations. + */ +void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops, + int cat) +{ + switch (cat) { + case LPROPS_DIRTY: + case LPROPS_DIRTY_IDX: + case LPROPS_FREE: + if (add_to_lpt_heap(c, lprops, cat)) + break; + /* No more room on heap so make it un-categorized */ + cat = LPROPS_UNCAT; + fallthrough; + case LPROPS_UNCAT: + list_add(&lprops->list, &c->uncat_list); + break; + case LPROPS_EMPTY: + list_add(&lprops->list, &c->empty_list); + break; + case LPROPS_FREEABLE: + list_add(&lprops->list, &c->freeable_list); + c->freeable_cnt += 1; + break; + case LPROPS_FRDI_IDX: + list_add(&lprops->list, &c->frdi_idx_list); + break; + default: + ubifs_assert(c, 0); + } + + lprops->flags &= ~LPROPS_CAT_MASK; + lprops->flags |= cat; + c->in_a_category_cnt += 1; + ubifs_assert(c, c->in_a_category_cnt <= c->main_lebs); +} + +/** + * ubifs_remove_from_cat - remove LEB properties from a category list or heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to remove + * @cat: LEB category from which to remove + * + * LEB properties are categorized to enable fast find operations. + */ +static void ubifs_remove_from_cat(struct ubifs_info *c, + struct ubifs_lprops *lprops, int cat) +{ + switch (cat) { + case LPROPS_DIRTY: + case LPROPS_DIRTY_IDX: + case LPROPS_FREE: + remove_from_lpt_heap(c, lprops, cat); + break; + case LPROPS_FREEABLE: + c->freeable_cnt -= 1; + ubifs_assert(c, c->freeable_cnt >= 0); + fallthrough; + case LPROPS_UNCAT: + case LPROPS_EMPTY: + case LPROPS_FRDI_IDX: + ubifs_assert(c, !list_empty(&lprops->list)); + list_del(&lprops->list); + break; + default: + ubifs_assert(c, 0); + } + + c->in_a_category_cnt -= 1; + ubifs_assert(c, c->in_a_category_cnt >= 0); +} + +/** + * ubifs_replace_cat - replace lprops in a category list or heap. + * @c: UBIFS file-system description object + * @old_lprops: LEB properties to replace + * @new_lprops: LEB properties with which to replace + * + * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode) + * and the lprops that the pnode contains. When that happens, references in + * category lists and heaps must be replaced. This function does that. + */ +void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops, + struct ubifs_lprops *new_lprops) +{ + int cat; + + cat = new_lprops->flags & LPROPS_CAT_MASK; + switch (cat) { + case LPROPS_DIRTY: + case LPROPS_DIRTY_IDX: + case LPROPS_FREE: + lpt_heap_replace(c, new_lprops, cat); + break; + case LPROPS_UNCAT: + case LPROPS_EMPTY: + case LPROPS_FREEABLE: + case LPROPS_FRDI_IDX: + list_replace(&old_lprops->list, &new_lprops->list); + break; + default: + ubifs_assert(c, 0); + } +} + +/** + * ubifs_ensure_cat - ensure LEB properties are categorized. + * @c: UBIFS file-system description object + * @lprops: LEB properties + * + * A LEB may have fallen off of the bottom of a heap, and ended up as + * un-categorized even though it has enough space for us now. If that is the + * case this function will put the LEB back onto a heap. + */ +void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops) +{ + int cat = lprops->flags & LPROPS_CAT_MASK; + + if (cat != LPROPS_UNCAT) + return; + cat = ubifs_categorize_lprops(c, lprops); + if (cat == LPROPS_UNCAT) + return; + ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT); + ubifs_add_to_cat(c, lprops, cat); +} + +/** + * ubifs_categorize_lprops - categorize LEB properties. + * @c: UBIFS file-system description object + * @lprops: LEB properties to categorize + * + * LEB properties are categorized to enable fast find operations. This function + * returns the LEB category to which the LEB properties belong. Note however + * that if the LEB category is stored as a heap and the heap is full, the + * LEB properties may have their category changed to %LPROPS_UNCAT. + */ +int ubifs_categorize_lprops(const struct ubifs_info *c, + const struct ubifs_lprops *lprops) +{ + if (lprops->flags & LPROPS_TAKEN) + return LPROPS_UNCAT; + + if (lprops->free == c->leb_size) { + ubifs_assert(c, !(lprops->flags & LPROPS_INDEX)); + return LPROPS_EMPTY; + } + + if (lprops->free + lprops->dirty == c->leb_size) { + if (lprops->flags & LPROPS_INDEX) + return LPROPS_FRDI_IDX; + else + return LPROPS_FREEABLE; + } + + if (lprops->flags & LPROPS_INDEX) { + if (lprops->dirty + lprops->free >= c->min_idx_node_sz) + return LPROPS_DIRTY_IDX; + } else { + if (lprops->dirty >= c->dead_wm && + lprops->dirty > lprops->free) + return LPROPS_DIRTY; + if (lprops->free > 0) + return LPROPS_FREE; + } + + return LPROPS_UNCAT; +} + +/** + * change_category - change LEB properties category. + * @c: UBIFS file-system description object + * @lprops: LEB properties to re-categorize + * + * LEB properties are categorized to enable fast find operations. When the LEB + * properties change they must be re-categorized. + */ +static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops) +{ + int old_cat = lprops->flags & LPROPS_CAT_MASK; + int new_cat = ubifs_categorize_lprops(c, lprops); + + if (old_cat == new_cat) { + struct ubifs_lpt_heap *heap; + + /* lprops on a heap now must be moved up or down */ + if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT) + return; /* Not on a heap */ + heap = &c->lpt_heap[new_cat - 1]; + adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat); + } else { + ubifs_remove_from_cat(c, lprops, old_cat); + ubifs_add_to_cat(c, lprops, new_cat); + } +} + +/** + * ubifs_calc_dark - calculate LEB dark space size. + * @c: the UBIFS file-system description object + * @spc: amount of free and dirty space in the LEB + * + * This function calculates and returns amount of dark space in an LEB which + * has @spc bytes of free and dirty space. + * + * UBIFS is trying to account the space which might not be usable, and this + * space is called "dark space". For example, if an LEB has only %512 free + * bytes, it is dark space, because it cannot fit a large data node. + */ +int ubifs_calc_dark(const struct ubifs_info *c, int spc) +{ + ubifs_assert(c, !(spc & 7)); + + if (spc < c->dark_wm) + return spc; + + /* + * If we have slightly more space then the dark space watermark, we can + * anyway safely assume it we'll be able to write a node of the + * smallest size there. + */ + if (spc - c->dark_wm < MIN_WRITE_SZ) + return spc - MIN_WRITE_SZ; + + return c->dark_wm; +} + +/** + * is_lprops_dirty - determine if LEB properties are dirty. + * @c: the UBIFS file-system description object + * @lprops: LEB properties to test + */ +static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops) +{ + struct ubifs_pnode *pnode; + int pos; + + pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1); + pnode = (struct ubifs_pnode *)container_of(lprops - pos, + struct ubifs_pnode, + lprops[0]); + return !test_bit(COW_CNODE, &pnode->flags) && + test_bit(DIRTY_CNODE, &pnode->flags); +} + +/** + * ubifs_change_lp - change LEB properties. + * @c: the UBIFS file-system description object + * @lp: LEB properties to change + * @free: new free space amount + * @dirty: new dirty space amount + * @flags: new flags + * @idx_gc_cnt: change to the count of @idx_gc list + * + * This function changes LEB properties (@free, @dirty or @flag). However, the + * property which has the %LPROPS_NC value is not changed. Returns a pointer to + * the updated LEB properties on success and a negative error code on failure. + * + * Note, the LEB properties may have had to be copied (due to COW) and + * consequently the pointer returned may not be the same as the pointer + * passed. + */ +const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c, + const struct ubifs_lprops *lp, + int free, int dirty, int flags, + int idx_gc_cnt) +{ + /* + * This is the only function that is allowed to change lprops, so we + * discard the "const" qualifier. + */ + struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp; + + dbg_lp("LEB %d, free %d, dirty %d, flags %d", + lprops->lnum, free, dirty, flags); + + ubifs_assert(c, mutex_is_locked(&c->lp_mutex)); + ubifs_assert(c, c->lst.empty_lebs >= 0 && + c->lst.empty_lebs <= c->main_lebs); + ubifs_assert(c, c->freeable_cnt >= 0); + ubifs_assert(c, c->freeable_cnt <= c->main_lebs); + ubifs_assert(c, c->lst.taken_empty_lebs >= 0); + ubifs_assert(c, c->lst.taken_empty_lebs <= c->lst.empty_lebs); + ubifs_assert(c, !(c->lst.total_free & 7) && !(c->lst.total_dirty & 7)); + ubifs_assert(c, !(c->lst.total_dead & 7) && !(c->lst.total_dark & 7)); + ubifs_assert(c, !(c->lst.total_used & 7)); + ubifs_assert(c, free == LPROPS_NC || free >= 0); + ubifs_assert(c, dirty == LPROPS_NC || dirty >= 0); + + if (!is_lprops_dirty(c, lprops)) { + lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum); + if (IS_ERR(lprops)) + return lprops; + } else + ubifs_assert(c, lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum)); + + ubifs_assert(c, !(lprops->free & 7) && !(lprops->dirty & 7)); + + spin_lock(&c->space_lock); + if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size) + c->lst.taken_empty_lebs -= 1; + + if (!(lprops->flags & LPROPS_INDEX)) { + int old_spc; + + old_spc = lprops->free + lprops->dirty; + if (old_spc < c->dead_wm) + c->lst.total_dead -= old_spc; + else + c->lst.total_dark -= ubifs_calc_dark(c, old_spc); + + c->lst.total_used -= c->leb_size - old_spc; + } + + if (free != LPROPS_NC) { + free = ALIGN(free, 8); + c->lst.total_free += free - lprops->free; + + /* Increase or decrease empty LEBs counter if needed */ + if (free == c->leb_size) { + if (lprops->free != c->leb_size) + c->lst.empty_lebs += 1; + } else if (lprops->free == c->leb_size) + c->lst.empty_lebs -= 1; + lprops->free = free; + } + + if (dirty != LPROPS_NC) { + dirty = ALIGN(dirty, 8); + c->lst.total_dirty += dirty - lprops->dirty; + lprops->dirty = dirty; + } + + if (flags != LPROPS_NC) { + /* Take care about indexing LEBs counter if needed */ + if ((lprops->flags & LPROPS_INDEX)) { + if (!(flags & LPROPS_INDEX)) + c->lst.idx_lebs -= 1; + } else if (flags & LPROPS_INDEX) + c->lst.idx_lebs += 1; + lprops->flags = flags; + } + + if (!(lprops->flags & LPROPS_INDEX)) { + int new_spc; + + new_spc = lprops->free + lprops->dirty; + if (new_spc < c->dead_wm) + c->lst.total_dead += new_spc; + else + c->lst.total_dark += ubifs_calc_dark(c, new_spc); + + c->lst.total_used += c->leb_size - new_spc; + } + + if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size) + c->lst.taken_empty_lebs += 1; + + change_category(c, lprops); + c->idx_gc_cnt += idx_gc_cnt; + spin_unlock(&c->space_lock); + return lprops; +} + +/** + * ubifs_get_lp_stats - get lprops statistics. + * @c: UBIFS file-system description object + * @lst: return statistics + */ +void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst) +{ + spin_lock(&c->space_lock); + memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats)); + spin_unlock(&c->space_lock); +} + +/** + * ubifs_change_one_lp - change LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to change properties for + * @free: amount of free space + * @dirty: amount of dirty space + * @flags_set: flags to set + * @flags_clean: flags to clean + * @idx_gc_cnt: change to the count of idx_gc list + * + * This function changes properties of LEB @lnum. It is a helper wrapper over + * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the + * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and + * a negative error code in case of failure. + */ +int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean, int idx_gc_cnt) +{ + int err = 0, flags; + const struct ubifs_lprops *lp; + + if (!test_lpt_valid_callback(c, lnum, LPROPS_NC, LPROPS_NC, LPROPS_NC, + LPROPS_NC)) + return 0; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) && + can_ignore_failure_callback(c, FR_LPT_CORRUPTED)) + err = 0; + goto out; + } + + if (!test_lpt_valid_callback(c, lnum, lp->free, lp->dirty, free, dirty)) + goto out; + + flags = (lp->flags | flags_set) & ~flags_clean; + lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt); + if (IS_ERR(lp)) + err = PTR_ERR(lp); + +out: + ubifs_release_lprops(c); + if (err) + ubifs_err(c, "cannot change properties of LEB %d, error %d", + lnum, err); + return err; +} + +/** + * ubifs_update_one_lp - update LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to change properties for + * @free: amount of free space + * @dirty: amount of dirty space to add + * @flags_set: flags to set + * @flags_clean: flags to clean + * + * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to + * current dirty space, not substitutes it. + */ +int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean) +{ + int err = 0, flags; + const struct ubifs_lprops *lp; + + if (!test_lpt_valid_callback(c, lnum, LPROPS_NC, LPROPS_NC, LPROPS_NC, + LPROPS_NC)) + return 0; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) && + can_ignore_failure_callback(c, FR_LPT_CORRUPTED)) + err = 0; + goto out; + } + + if (!test_lpt_valid_callback(c, lnum, lp->free, lp->dirty, free, + lp->dirty + dirty)) + goto out; + + flags = (lp->flags | flags_set) & ~flags_clean; + lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0); + if (IS_ERR(lp)) + err = PTR_ERR(lp); + +out: + ubifs_release_lprops(c); + if (err) + ubifs_err(c, "cannot update properties of LEB %d, error %d", + lnum, err); + return err; +} + +/** + * ubifs_read_one_lp - read LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to read properties for + * @lp: where to store read properties + * + * This helper function reads properties of a LEB @lnum and stores them in @lp. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp) +{ + int err = 0; + const struct ubifs_lprops *lpp; + + ubifs_get_lprops(c); + + lpp = ubifs_lpt_lookup(c, lnum); + if (IS_ERR(lpp)) { + err = PTR_ERR(lpp); + ubifs_err(c, "cannot read properties of LEB %d, error %d", + lnum, err); + goto out; + } + + memcpy(lp, lpp, sizeof(struct ubifs_lprops)); + +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_fast_find_free - try to find a LEB with free space quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for a LEB with free space or %NULL if + * the function is unable to find a LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + struct ubifs_lpt_heap *heap; + + ubifs_assert(c, mutex_is_locked(&c->lp_mutex)); + + heap = &c->lpt_heap[LPROPS_FREE - 1]; + if (heap->cnt == 0) + return NULL; + + lprops = heap->arr[0]; + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, !(lprops->flags & LPROPS_INDEX)); + return lprops; +} + +/** + * ubifs_fast_find_empty - try to find an empty LEB quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for an empty LEB or %NULL if the + * function is unable to find an empty LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + + ubifs_assert(c, mutex_is_locked(&c->lp_mutex)); + + if (list_empty(&c->empty_list)) + return NULL; + + lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list); + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, !(lprops->flags & LPROPS_INDEX)); + ubifs_assert(c, lprops->free == c->leb_size); + return lprops; +} + +/** + * ubifs_fast_find_freeable - try to find a freeable LEB quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for a freeable LEB or %NULL if the + * function is unable to find a freeable LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + + ubifs_assert(c, mutex_is_locked(&c->lp_mutex)); + + if (list_empty(&c->freeable_list)) + return NULL; + + lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list); + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, !(lprops->flags & LPROPS_INDEX)); + ubifs_assert(c, lprops->free + lprops->dirty == c->leb_size); + ubifs_assert(c, c->freeable_cnt > 0); + return lprops; +} + +/** + * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for a freeable index LEB or %NULL if the + * function is unable to find a freeable index LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + + ubifs_assert(c, mutex_is_locked(&c->lp_mutex)); + + if (list_empty(&c->frdi_idx_list)) + return NULL; + + lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list); + ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(c, (lprops->flags & LPROPS_INDEX)); + ubifs_assert(c, lprops->free + lprops->dirty == c->leb_size); + return lprops; +} diff --git a/ubifs-utils/libubifs/lpt.c b/ubifs-utils/libubifs/lpt.c new file mode 100644 index 0000000..f2f2727 --- /dev/null +++ b/ubifs-utils/libubifs/lpt.c @@ -0,0 +1,2338 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the LEB properties tree (LPT) area. The LPT area + * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and + * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits + * between the log and the orphan area. + * + * The LPT area is like a miniature self-contained file system. It is required + * that it never runs out of space, is fast to access and update, and scales + * logarithmically. The LEB properties tree is implemented as a wandering tree + * much like the TNC, and the LPT area has its own garbage collection. + * + * The LPT has two slightly different forms called the "small model" and the + * "big model". The small model is used when the entire LEB properties table + * can be written into a single eraseblock. In that case, garbage collection + * consists of just writing the whole table, which therefore makes all other + * eraseblocks reusable. In the case of the big model, dirty eraseblocks are + * selected for garbage collection, which consists of marking the clean nodes in + * that LEB as dirty, and then only the dirty nodes are written out. Also, in + * the case of the big model, a table of LEB numbers is saved so that the entire + * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first + * mounted. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "crc16.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" + +/** + * do_calc_lpt_geom - calculate sizes for the LPT area. + * @c: the UBIFS file-system description object + * + * Calculate the sizes of LPT bit fields, nodes, and tree, based on the + * properties of the flash and whether LPT is "big" (c->big_lpt). + */ +static void do_calc_lpt_geom(struct ubifs_info *c) +{ + int i, n, bits, per_leb_wastage, max_pnode_cnt; + long long sz, tot_wastage; + + if (c->program_type != MKFS_PROGRAM_TYPE) { + n = c->main_lebs + c->max_leb_cnt - c->leb_cnt; + max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT); + } else { + /* + * Different from linux kernel. + * + * We change it, because 'c->leb_cnt' is not initialized in + * mkfs.ubifs when do_calc_lpt_geom() is invoked, 'c->main_lebs' + * is calculated by 'c->max_leb_cnt', so the 'c->lpt_hght' + * should be calculated by 'c->main_lebs'. + */ + max_pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); + } + + c->lpt_hght = 1; + n = UBIFS_LPT_FANOUT; + while (n < max_pnode_cnt) { + c->lpt_hght += 1; + n <<= UBIFS_LPT_FANOUT_SHIFT; + } + + c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); + + n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT); + c->nnode_cnt = n; + for (i = 1; i < c->lpt_hght; i++) { + n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT); + c->nnode_cnt += n; + } + + c->space_bits = fls(c->leb_size) - 3; + c->lpt_lnum_bits = fls(c->lpt_lebs); + c->lpt_offs_bits = fls(c->leb_size - 1); + c->lpt_spc_bits = fls(c->leb_size); + + n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT); + c->pcnt_bits = fls(n - 1); + + c->lnum_bits = fls(c->max_leb_cnt - 1); + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + (c->big_lpt ? c->pcnt_bits : 0) + + (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT; + c->pnode_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + (c->big_lpt ? c->pcnt_bits : 0) + + (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT; + c->nnode_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + c->lpt_lebs * c->lpt_spc_bits * 2; + c->ltab_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + c->lnum_bits * c->lsave_cnt; + c->lsave_sz = (bits + 7) / 8; + + /* Calculate the minimum LPT size */ + c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz; + c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz; + c->lpt_sz += c->ltab_sz; + if (c->big_lpt) + c->lpt_sz += c->lsave_sz; + + /* Add wastage */ + sz = c->lpt_sz; + per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz); + sz += per_leb_wastage; + tot_wastage = per_leb_wastage; + while (sz > c->leb_size) { + sz += per_leb_wastage; + sz -= c->leb_size; + tot_wastage += per_leb_wastage; + } + tot_wastage += ALIGN(sz, c->min_io_size) - sz; + c->lpt_sz += tot_wastage; +} + +/** + * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area. + * @c: the UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_calc_lpt_geom(struct ubifs_info *c) +{ + int lebs_needed; + long long sz; + + do_calc_lpt_geom(c); + + /* Verify that lpt_lebs is big enough */ + sz = c->lpt_sz * 2; /* Must have at least 2 times the size */ + lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size); + if (lebs_needed > c->lpt_lebs) { + ubifs_err(c, "too few LPT LEBs"); + return -EINVAL; + } + + /* Verify that ltab fits in a single LEB (since ltab is a single node */ + if (c->ltab_sz > c->leb_size) { + ubifs_err(c, "LPT ltab too big"); + return -EINVAL; + } + + c->check_lpt_free = c->big_lpt; + return 0; +} + +/** + * ubifs_calc_dflt_lpt_geom - calculate default LPT geometry. + * @c: the UBIFS file-system description object + * @main_lebs: number of main area LEBs is passed and returned here + * @big_lpt: whether the LPT area is "big" is returned here + * + * The size of the LPT area depends on parameters that themselves are dependent + * on the size of the LPT area. This function, successively recalculates the LPT + * area geometry until the parameters and resultant geometry are consistent. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs, int *big_lpt) +{ + int i, lebs_needed; + long long sz; + + /* Start by assuming the minimum number of LPT LEBs */ + c->lpt_lebs = UBIFS_MIN_LPT_LEBS; + c->main_lebs = *main_lebs - c->lpt_lebs; + if (c->main_lebs <= 0) + return -EINVAL; + + /* And assume we will use the small LPT model */ + c->big_lpt = 0; + + /* + * Calculate the geometry based on assumptions above and then see if it + * makes sense + */ + do_calc_lpt_geom(c); + + /* Small LPT model must have lpt_sz < leb_size */ + if (c->lpt_sz > c->leb_size) { + /* Nope, so try again using big LPT model */ + c->big_lpt = 1; + do_calc_lpt_geom(c); + } + + /* Now check there are enough LPT LEBs */ + for (i = 0; i < 64 ; i++) { + sz = c->lpt_sz * 4; /* Allow 4 times the size */ + lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size); + if (lebs_needed > c->lpt_lebs) { + /* Not enough LPT LEBs so try again with more */ + c->lpt_lebs = lebs_needed; + c->main_lebs = *main_lebs - c->lpt_lebs; + if (c->main_lebs <= 0) + return -EINVAL; + do_calc_lpt_geom(c); + continue; + } + if (c->ltab_sz > c->leb_size) { + ubifs_err(c, "LPT ltab too big"); + return -EINVAL; + } + *main_lebs = c->main_lebs; + *big_lpt = c->big_lpt; + return 0; + } + return -EINVAL; +} + +/** + * pack_bits - pack bit fields end-to-end. + * @c: UBIFS file-system description object + * @addr: address at which to pack (passed and next address returned) + * @pos: bit position at which to pack (passed and next position returned) + * @val: value to pack + * @nrbits: number of bits of value to pack (1-32) + */ +static void pack_bits(const struct ubifs_info *c, uint8_t **addr, int *pos, uint32_t val, int nrbits) +{ + uint8_t *p = *addr; + int b = *pos; + + ubifs_assert(c, nrbits > 0); + ubifs_assert(c, nrbits <= 32); + ubifs_assert(c, *pos >= 0); + ubifs_assert(c, *pos < 8); + ubifs_assert(c, (val >> nrbits) == 0 || nrbits == 32); + if (b) { + *p |= ((uint8_t)val) << b; + nrbits += b; + if (nrbits > 8) { + *++p = (uint8_t)(val >>= (8 - b)); + if (nrbits > 16) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 24) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 32) + *++p = (uint8_t)(val >>= 8); + } + } + } + } else { + *p = (uint8_t)val; + if (nrbits > 8) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 16) { + *++p = (uint8_t)(val >>= 8); + if (nrbits > 24) + *++p = (uint8_t)(val >>= 8); + } + } + } + b = nrbits & 7; + if (b == 0) + p++; + *addr = p; + *pos = b; +} + +/** + * ubifs_unpack_bits - unpack bit fields. + * @c: UBIFS file-system description object + * @addr: address at which to unpack (passed and next address returned) + * @pos: bit position at which to unpack (passed and next position returned) + * @nrbits: number of bits of value to unpack (1-32) + * + * This functions returns the value unpacked. + */ +uint32_t ubifs_unpack_bits(const struct ubifs_info *c, uint8_t **addr, int *pos, int nrbits) +{ + const int k = 32 - nrbits; + uint8_t *p = *addr; + int b = *pos; + uint32_t val = 0; + const int bytes = (nrbits + b + 7) >> 3; + + ubifs_assert(c, nrbits > 0); + ubifs_assert(c, nrbits <= 32); + ubifs_assert(c, *pos >= 0); + ubifs_assert(c, *pos < 8); + if (b) { + switch (bytes) { + case 2: + val = p[1]; + break; + case 3: + val = p[1] | ((uint32_t)p[2] << 8); + break; + case 4: + val = p[1] | ((uint32_t)p[2] << 8) | + ((uint32_t)p[3] << 16); + break; + case 5: + val = p[1] | ((uint32_t)p[2] << 8) | + ((uint32_t)p[3] << 16) | + ((uint32_t)p[4] << 24); + } + val <<= (8 - b); + val |= *p >> b; + nrbits += b; + } else { + switch (bytes) { + case 1: + val = p[0]; + break; + case 2: + val = p[0] | ((uint32_t)p[1] << 8); + break; + case 3: + val = p[0] | ((uint32_t)p[1] << 8) | + ((uint32_t)p[2] << 16); + break; + case 4: + val = p[0] | ((uint32_t)p[1] << 8) | + ((uint32_t)p[2] << 16) | + ((uint32_t)p[3] << 24); + break; + } + } + val <<= k; + val >>= k; + b = nrbits & 7; + p += nrbits >> 3; + *addr = p; + *pos = b; + ubifs_assert(c, (val >> nrbits) == 0 || nrbits - b == 32); + return val; +} + +/** + * ubifs_pack_pnode - pack all the bit fields of a pnode. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @pnode: pnode to pack + */ +void ubifs_pack_pnode(struct ubifs_info *c, void *buf, + struct ubifs_pnode *pnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(c, &addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS); + if (c->big_lpt) + pack_bits(c, &addr, &pos, pnode->num, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + pack_bits(c, &addr, &pos, pnode->lprops[i].free >> 3, + c->space_bits); + pack_bits(c, &addr, &pos, pnode->lprops[i].dirty >> 3, + c->space_bits); + if (pnode->lprops[i].flags & LPROPS_INDEX) + pack_bits(c, &addr, &pos, 1, 1); + else + pack_bits(c, &addr, &pos, 0, 1); + } + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->pnode_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(c, &addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_pack_nnode - pack all the bit fields of a nnode. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @nnode: nnode to pack + */ +void ubifs_pack_nnode(struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(c, &addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS); + if (c->big_lpt) + pack_bits(c, &addr, &pos, nnode->num, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum = nnode->nbranch[i].lnum; + + if (lnum == 0) + lnum = c->lpt_last + 1; + pack_bits(c, &addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits); + pack_bits(c, &addr, &pos, nnode->nbranch[i].offs, + c->lpt_offs_bits); + } + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->nnode_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(c, &addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_pack_ltab - pack the LPT's own lprops table. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @ltab: LPT's own lprops table to pack + */ +void ubifs_pack_ltab(struct ubifs_info *c, void *buf, + struct ubifs_lpt_lprops *ltab) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(c, &addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS); + for (i = 0; i < c->lpt_lebs; i++) { + pack_bits(c, &addr, &pos, ltab[i].free, c->lpt_spc_bits); + pack_bits(c, &addr, &pos, ltab[i].dirty, c->lpt_spc_bits); + } + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->ltab_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(c, &addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_pack_lsave - pack the LPT's save table. + * @c: UBIFS file-system description object + * @buf: buffer into which to pack + * @lsave: LPT's save table to pack + */ +void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0; + uint16_t crc; + + pack_bits(c, &addr, &pos, UBIFS_LPT_LSAVE, UBIFS_LPT_TYPE_BITS); + for (i = 0; i < c->lsave_cnt; i++) + pack_bits(c, &addr, &pos, lsave[i], c->lnum_bits); + crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + c->lsave_sz - UBIFS_LPT_CRC_BYTES); + addr = buf; + pos = 0; + pack_bits(c, &addr, &pos, crc, UBIFS_LPT_CRC_BITS); +} + +/** + * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @lnum: LEB number to which to add dirty space + * @dirty: amount of dirty space to add + */ +void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty) +{ + if (!dirty || !lnum) + return; + dbg_lp("LEB %d add %d to %d", + lnum, dirty, c->ltab[lnum - c->lpt_first].dirty); + ubifs_assert(c, lnum >= c->lpt_first && lnum <= c->lpt_last); + c->ltab[lnum - c->lpt_first].dirty += dirty; +} + +/** + * set_ltab - set LPT LEB properties. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @free: amount of free space + * @dirty: amount of dirty space + */ +static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty) +{ + dbg_lp("LEB %d free %d dirty %d to %d %d", + lnum, c->ltab[lnum - c->lpt_first].free, + c->ltab[lnum - c->lpt_first].dirty, free, dirty); + ubifs_assert(c, lnum >= c->lpt_first && lnum <= c->lpt_last); + c->ltab[lnum - c->lpt_first].free = free; + c->ltab[lnum - c->lpt_first].dirty = dirty; +} + +/** + * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @nnode: nnode for which to add dirt + */ +void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode) +{ + struct ubifs_nnode *np = nnode->parent; + + if (np) + ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum, + c->nnode_sz); + else { + ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz); + if (!(c->lpt_drty_flgs & LTAB_DIRTY)) { + c->lpt_drty_flgs |= LTAB_DIRTY; + ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz); + } + } +} + +/** + * add_pnode_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @pnode: pnode for which to add dirt + */ +static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum, + c->pnode_sz); +} + +/** + * ubifs_calc_nnode_num - calculate nnode number. + * @row: the row in the tree (root is zero) + * @col: the column in the row (leftmost is zero) + * + * The nnode number is a number that uniquely identifies a nnode and can be used + * easily to traverse the tree from the root to that nnode. + * + * This function calculates and returns the nnode number for the nnode at @row + * and @col. + */ +int ubifs_calc_nnode_num(int row, int col) +{ + int num, bits; + + num = 1; + while (row--) { + bits = (col & (UBIFS_LPT_FANOUT - 1)); + col >>= UBIFS_LPT_FANOUT_SHIFT; + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= bits; + } + return num; +} + +/** + * calc_nnode_num_from_parent - calculate nnode number. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * The nnode number is a number that uniquely identifies a nnode and can be used + * easily to traverse the tree from the root to that nnode. + * + * This function calculates and returns the nnode number based on the parent's + * nnode number and the index in parent. + */ +static int calc_nnode_num_from_parent(const struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + int num, shft; + + if (!parent) + return 1; + shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT; + num = parent->num ^ (1 << shft); + num |= (UBIFS_LPT_FANOUT + iip) << shft; + return num; +} + +/** + * calc_pnode_num_from_parent - calculate pnode number. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * The pnode number is a number that uniquely identifies a pnode and can be used + * easily to traverse the tree from the root to that pnode. + * + * This function calculates and returns the pnode number based on the parent's + * nnode number and the index in parent. + */ +static int calc_pnode_num_from_parent(const struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0; + + for (i = 0; i < n; i++) { + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= pnum & (UBIFS_LPT_FANOUT - 1); + pnum >>= UBIFS_LPT_FANOUT_SHIFT; + } + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= iip; + return num; +} + +/** + * ubifs_create_lpt - create lpt acccording to lprops array. + * @c: UBIFS file-system description object + * @lps: array of logical eraseblock properties + * @lp_cnt: the length of @lps + * @hash: hash of the LPT is returned here + * @free_ltab: %true means to release c->ltab after creating lpt + * + * This function creates lpt, the pnode will be initialized based on + * corresponding elements in @lps. If there are no corresponding lprops + * (eg. @lp_cnt is smaller than @c->main_lebs), the LEB property is set + * as free state. + */ +int ubifs_create_lpt(struct ubifs_info *c, struct ubifs_lprops *lps, int lp_cnt, + u8 *hash, bool free_ltab) +{ + int lnum, err = 0, i, j, cnt, len, alen, row; + int blnum, boffs, bsz, bcnt; + struct ubifs_pnode *pnode = NULL; + struct ubifs_nnode *nnode = NULL; + void *buf = NULL, *p; + struct ubifs_lpt_lprops *ltab = NULL; + int *lsave = NULL; + struct shash_desc *desc; + + desc = ubifs_hash_get_desc(c); + if (IS_ERR(desc)) + return PTR_ERR(desc); + + lsave = kmalloc_array(c->lsave_cnt, sizeof(int), GFP_KERNEL); + pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL); + nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL); + buf = vmalloc(c->leb_size); + ltab = vmalloc(array_size(sizeof(struct ubifs_lpt_lprops), + c->lpt_lebs)); + if (!pnode || !nnode || !buf || !ltab || !lsave) { + err = -ENOMEM; + goto out; + } + + ubifs_assert(c, !c->ltab); + c->ltab = ltab; /* Needed by set_ltab */ + + /* Initialize LPT's own lprops */ + for (i = 0; i < c->lpt_lebs; i++) { + ltab[i].free = c->leb_size; + ltab[i].dirty = 0; + ltab[i].tgc = 0; + ltab[i].cmt = 0; + } + + lnum = c->lpt_first; + p = buf; + len = 0; + /* + * Different from linux kernel. The number of leaf nodes (pnodes) should + * be calculated by the number of current main LEBs. The 'c->pnode_cnt' + * may not be equal to 'DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT)' in + * mkfs when 'c->leb_cnt != c->max_leb_cnt' is true. + */ + cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); + + /* + * To calculate the internal node branches, we keep information about + * the level below. + */ + blnum = lnum; /* LEB number of level below */ + boffs = 0; /* Offset of level below */ + bcnt = cnt; /* Number of nodes in level below */ + bsz = c->pnode_sz; /* Size of nodes in level below */ + + /* Add all pnodes */ + for (i = 0; i < cnt; i++) { + if (len + c->pnode_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + /* + * Different from linux kernel. + * The mkfs may partially write data into a certain LEB + * of file image, the left unwritten area in the LEB + * should be filled with '0xFF'. + */ + if (c->libubi) { + memset(p, 0xff, alen - len); + err = ubifs_leb_change(c, lnum++, buf, alen); + } else { + memset(p, 0xff, c->leb_size - len); + err = ubifs_leb_change(c, lnum++, buf, c->leb_size); + } + if (err) + goto out; + p = buf; + len = 0; + } + /* Fill in the pnode */ + for (j = 0; j < UBIFS_LPT_FANOUT; j++) { + int k = (i << UBIFS_LPT_FANOUT_SHIFT) + j; + + if (k < lp_cnt) { + pnode->lprops[j].free = lps[k].free; + pnode->lprops[j].dirty = lps[k].dirty; + pnode->lprops[j].flags = lps[k].flags; + } else { + pnode->lprops[j].free = c->leb_size; + pnode->lprops[j].dirty = 0; + pnode->lprops[j].flags = 0; + } + } + ubifs_pack_pnode(c, p, pnode); + err = ubifs_shash_update(c, desc, p, c->pnode_sz); + if (err) + goto out; + + p += c->pnode_sz; + len += c->pnode_sz; + /* + * pnodes are simply numbered left to right starting at zero, + * which means the pnode number can be used easily to traverse + * down the tree to the corresponding pnode. + */ + pnode->num += 1; + } + + /* + * Different from linux kernel. The 'c->lpt_hght' is calculated by the + * 'c->max_leb_cnt', according to the implementation of function + * ubifs_pnode_lookup(), there are at least 'c->lpt_hght' cnodes should + * be created, otherwise the LPT looking up could be failed after + * mouting. + */ + row = c->lpt_hght - 1; + /* Add all nnodes, one level at a time */ + while (1) { + /* Number of internal nodes (nnodes) at next level */ + cnt = DIV_ROUND_UP(cnt, UBIFS_LPT_FANOUT); + if (cnt == 0) + cnt = 1; + for (i = 0; i < cnt; i++) { + if (len + c->nnode_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, + alen - len); + /* + * Different from linux kernel. + * The mkfs may partially write data into a certain LEB + * of file image, the left unwritten area in the LEB + * should be filled with '0xFF'. + */ + if (c->libubi) { + memset(p, 0xff, alen - len); + err = ubifs_leb_change(c, lnum++, buf, alen); + } else { + memset(p, 0xff, c->leb_size - len); + err = ubifs_leb_change(c, lnum++, buf, c->leb_size); + } + if (err) + goto out; + p = buf; + len = 0; + } + /* Only 1 nnode at this level, so it is the root */ + if (row == 0) { + c->lpt_lnum = lnum; + c->lpt_offs = len; + } + /* Set branches to the level below */ + for (j = 0; j < UBIFS_LPT_FANOUT; j++) { + if (bcnt) { + if (boffs + bsz > c->leb_size) { + blnum += 1; + boffs = 0; + } + nnode->nbranch[j].lnum = blnum; + nnode->nbranch[j].offs = boffs; + boffs += bsz; + bcnt--; + } else { + nnode->nbranch[j].lnum = 0; + nnode->nbranch[j].offs = 0; + } + } + nnode->num = ubifs_calc_nnode_num(row, i); + ubifs_pack_nnode(c, p, nnode); + p += c->nnode_sz; + len += c->nnode_sz; + } + /* Row zero is the top row */ + if (row == 0) + break; + /* Update the information about the level below */ + bcnt = cnt; + bsz = c->nnode_sz; + row -= 1; + } + + if (c->big_lpt) { + /* Need to add LPT's save table */ + if (len + c->lsave_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + /* + * Different from linux kernel. + * The mkfs may partially write data into a certain LEB + * of file image, the left unwritten area in the LEB + * should be filled with '0xFF'. + */ + if (c->libubi) { + memset(p, 0xff, alen - len); + err = ubifs_leb_change(c, lnum++, buf, alen); + } else { + memset(p, 0xff, c->leb_size - len); + err = ubifs_leb_change(c, lnum++, buf, c->leb_size); + } + if (err) + goto out; + p = buf; + len = 0; + } + + c->lsave_lnum = lnum; + c->lsave_offs = len; + + for (i = 0; i < c->lsave_cnt && i < c->main_lebs; i++) + lsave[i] = c->main_first + i; + for (; i < c->lsave_cnt; i++) + lsave[i] = c->main_first; + + ubifs_pack_lsave(c, p, lsave); + p += c->lsave_sz; + len += c->lsave_sz; + } + + /* Need to add LPT's own LEB properties table */ + if (len + c->ltab_sz > c->leb_size) { + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + /* + * Different from linux kernel. + * The mkfs may partially write data into a certain LEB + * of file image, the left unwritten area in the LEB + * should be filled with '0xFF'. + */ + if (c->libubi) { + memset(p, 0xff, alen - len); + err = ubifs_leb_change(c, lnum++, buf, alen); + } else { + memset(p, 0xff, c->leb_size - len); + err = ubifs_leb_change(c, lnum++, buf, c->leb_size); + } + if (err) + goto out; + p = buf; + len = 0; + } + + c->ltab_lnum = lnum; + c->ltab_offs = len; + + /* Update ltab before packing it */ + len += c->ltab_sz; + alen = ALIGN(len, c->min_io_size); + set_ltab(c, lnum, c->leb_size - alen, alen - len); + + ubifs_pack_ltab(c, p, ltab); + p += c->ltab_sz; + + /* Write remaining buffer */ + /* + * Different from linux kernel. + * The mkfs may partially write data into a certain LEB + * of file image, the left unwritten area in the LEB + * should be filled with '0xFF'. + */ + if (c->libubi) { + memset(p, 0xff, alen - len); + err = ubifs_leb_change(c, lnum, buf, alen); + } else { + memset(p, 0xff, c->leb_size - len); + err = ubifs_leb_change(c, lnum, buf, c->leb_size); + } + if (err) + goto out; + + if (c->big_lpt && c->lsave) + memcpy(c->lsave, lsave, c->lsave_cnt * sizeof(int)); + + err = ubifs_shash_final(c, desc, hash); + if (err) + goto out; + + c->nhead_lnum = lnum; + c->nhead_offs = ALIGN(len, c->min_io_size); + + dbg_lp("space_bits %d", c->space_bits); + dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits); + dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits); + dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits); + dbg_lp("pcnt_bits %d", c->pcnt_bits); + dbg_lp("lnum_bits %d", c->lnum_bits); + dbg_lp("pnode_sz %d", c->pnode_sz); + dbg_lp("nnode_sz %d", c->nnode_sz); + dbg_lp("ltab_sz %d", c->ltab_sz); + dbg_lp("lsave_sz %d", c->lsave_sz); + dbg_lp("lsave_cnt %d", c->lsave_cnt); + dbg_lp("lpt_hght %d", c->lpt_hght); + dbg_lp("big_lpt %u", c->big_lpt); + dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs); + dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs); + dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs); + if (c->big_lpt) + dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs); +out: + if (free_ltab || err) { + c->ltab = NULL; + vfree(ltab); + } + kfree(desc); + kfree(lsave); + vfree(buf); + kfree(nnode); + kfree(pnode); + return err; +} + +/** + * update_cats - add LEB properties of a pnode to LEB category lists and heaps. + * @c: UBIFS file-system description object + * @pnode: pnode + * + * When a pnode is loaded into memory, the LEB properties it contains are added, + * by this function, to the LEB category lists and heaps. + */ +static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + int i; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK; + int lnum = pnode->lprops[i].lnum; + + if (!lnum) + return; + ubifs_add_to_cat(c, &pnode->lprops[i], cat); + } +} + +/** + * replace_cats - add LEB properties of a pnode to LEB category lists and heaps. + * @c: UBIFS file-system description object + * @old_pnode: pnode copied + * @new_pnode: pnode copy + * + * During commit it is sometimes necessary to copy a pnode + * (see dirty_cow_pnode). When that happens, references in + * category lists and heaps must be replaced. This function does that. + */ +static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode, + struct ubifs_pnode *new_pnode) +{ + int i; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (!new_pnode->lprops[i].lnum) + return; + ubifs_replace_cat(c, &old_pnode->lprops[i], + &new_pnode->lprops[i]); + } +} + +/** + * check_lpt_crc - check LPT node crc is correct. + * @c: UBIFS file-system description object + * @buf: buffer containing node + * @len: length of node + * + * This function returns %0 on success and a negative error code on failure. + */ +static int check_lpt_crc(const struct ubifs_info *c, void *buf, int len) +{ + int pos = 0; + uint8_t *addr = buf; + uint16_t crc, calc_crc; + + crc = ubifs_unpack_bits(c, &addr, &pos, UBIFS_LPT_CRC_BITS); + calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + len - UBIFS_LPT_CRC_BYTES); + if (crc != calc_crc) { + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + ubifs_err(c, "invalid crc in LPT node: crc %hx calc %hx", + crc, calc_crc); + dump_stack(); + return -EINVAL; + } + return 0; +} + +/** + * check_lpt_type - check LPT node type is correct. + * @c: UBIFS file-system description object + * @addr: address of type bit field is passed and returned updated here + * @pos: position of type bit field is passed and returned updated here + * @type: expected type + * + * This function returns %0 on success and a negative error code on failure. + */ +static int check_lpt_type(const struct ubifs_info *c, uint8_t **addr, + int *pos, int type) +{ + int node_type; + + node_type = ubifs_unpack_bits(c, addr, pos, UBIFS_LPT_TYPE_BITS); + if (node_type != type) { + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + ubifs_err(c, "invalid type (%d) in LPT node type %d", + node_type, type); + dump_stack(); + return -EINVAL; + } + return 0; +} + +/** + * unpack_pnode - unpack a pnode. + * @c: UBIFS file-system description object + * @buf: buffer containing packed pnode to unpack + * @pnode: pnode structure to fill + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_pnode(const struct ubifs_info *c, void *buf, + struct ubifs_pnode *pnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_PNODE); + if (err) + return err; + if (c->big_lpt) + pnode->num = ubifs_unpack_bits(c, &addr, &pos, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_lprops * const lprops = &pnode->lprops[i]; + + lprops->free = ubifs_unpack_bits(c, &addr, &pos, c->space_bits); + lprops->free <<= 3; + lprops->dirty = ubifs_unpack_bits(c, &addr, &pos, c->space_bits); + lprops->dirty <<= 3; + + if (ubifs_unpack_bits(c, &addr, &pos, 1)) + lprops->flags = LPROPS_INDEX; + else + lprops->flags = 0; + lprops->flags |= ubifs_categorize_lprops(c, lprops); + } + err = check_lpt_crc(c, buf, c->pnode_sz); + return err; +} + +/** + * ubifs_unpack_nnode - unpack a nnode. + * @c: UBIFS file-system description object + * @buf: buffer containing packed nnode to unpack + * @nnode: nnode structure to fill + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_NNODE); + if (err) + return err; + if (c->big_lpt) + nnode->num = ubifs_unpack_bits(c, &addr, &pos, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum; + + lnum = ubifs_unpack_bits(c, &addr, &pos, c->lpt_lnum_bits) + + c->lpt_first; + if (lnum == c->lpt_last + 1) + lnum = 0; + nnode->nbranch[i].lnum = lnum; + nnode->nbranch[i].offs = ubifs_unpack_bits(c, &addr, &pos, + c->lpt_offs_bits); + } + err = check_lpt_crc(c, buf, c->nnode_sz); + return err; +} + +/** + * unpack_ltab - unpack the LPT's own lprops table. + * @c: UBIFS file-system description object + * @buf: buffer from which to unpack + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_ltab(const struct ubifs_info *c, void *buf) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_LTAB); + if (err) + return err; + for (i = 0; i < c->lpt_lebs; i++) { + int free = ubifs_unpack_bits(c, &addr, &pos, c->lpt_spc_bits); + int dirty = ubifs_unpack_bits(c, &addr, &pos, c->lpt_spc_bits); + + if (free < 0 || free > c->leb_size || dirty < 0 || + dirty > c->leb_size || free + dirty > c->leb_size) { + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + return -EINVAL; + } + + c->ltab[i].free = free; + c->ltab[i].dirty = dirty; + c->ltab[i].tgc = 0; + c->ltab[i].cmt = 0; + } + err = check_lpt_crc(c, buf, c->ltab_sz); + return err; +} + +/** + * unpack_lsave - unpack the LPT's save table. + * @c: UBIFS file-system description object + * @buf: buffer from which to unpack + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_lsave(const struct ubifs_info *c, void *buf) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_LSAVE); + if (err) + return err; + for (i = 0; i < c->lsave_cnt; i++) { + int lnum = ubifs_unpack_bits(c, &addr, &pos, c->lnum_bits); + + if (lnum < c->main_first || lnum >= c->leb_cnt) { + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + return -EINVAL; + } + c->lsave[i] = lnum; + } + err = check_lpt_crc(c, buf, c->lsave_sz); + return err; +} + +/** + * validate_nnode - validate a nnode. + * @c: UBIFS file-system description object + * @nnode: nnode to validate + * @parent: parent nnode (or NULL for the root nnode) + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int validate_nnode(const struct ubifs_info *c, struct ubifs_nnode *nnode, + struct ubifs_nnode *parent, int iip) +{ + int i, lvl, max_offs; + + if (c->big_lpt) { + int num = calc_nnode_num_from_parent(c, parent, iip); + + if (nnode->num != num) + goto out_invalid; + } + lvl = parent ? parent->level - 1 : c->lpt_hght; + if (lvl < 1) + goto out_invalid; + if (lvl == 1) + max_offs = c->leb_size - c->pnode_sz; + else + max_offs = c->leb_size - c->nnode_sz; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum = nnode->nbranch[i].lnum; + int offs = nnode->nbranch[i].offs; + + if (lnum == 0) { + if (offs != 0) + goto out_invalid; + continue; + } + if (lnum < c->lpt_first || lnum > c->lpt_last) + goto out_invalid; + if (offs < 0 || offs > max_offs) + goto out_invalid; + } + return 0; + +out_invalid: + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + return -EINVAL; +} + +/** + * validate_pnode - validate a pnode. + * @c: UBIFS file-system description object + * @pnode: pnode to validate + * @parent: parent nnode + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int validate_pnode(const struct ubifs_info *c, struct ubifs_pnode *pnode, + struct ubifs_nnode *parent, int iip) +{ + int i; + + if (c->big_lpt) { + int num = calc_pnode_num_from_parent(c, parent, iip); + + if (pnode->num != num) + goto out_invalid; + } + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int free = pnode->lprops[i].free; + int dirty = pnode->lprops[i].dirty; + + if (free < 0 || free > c->leb_size || free % c->min_io_size || + (free & 7)) + goto out_invalid; + if (dirty < 0 || dirty > c->leb_size || (dirty & 7)) + goto out_invalid; + if (dirty + free > c->leb_size) + goto out_invalid; + } + return 0; + +out_invalid: + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + return -EINVAL; +} + +/** + * set_pnode_lnum - set LEB numbers on a pnode. + * @c: UBIFS file-system description object + * @pnode: pnode to update + * + * This function calculates the LEB numbers for the LEB properties it contains + * based on the pnode number. + */ +static void set_pnode_lnum(const struct ubifs_info *c, + struct ubifs_pnode *pnode) +{ + int i, lnum; + + lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (lnum >= c->leb_cnt) + return; + pnode->lprops[i].lnum = lnum++; + } +} + +/** + * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory. + * @c: UBIFS file-system description object + * @parent: parent nnode (or NULL for the root) + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch = NULL; + struct ubifs_nnode *nnode = NULL; + void *buf = c->lpt_nod_buf; + int err, lnum, offs; + + if (parent) { + branch = &parent->nbranch[iip]; + lnum = branch->lnum; + offs = branch->offs; + } else { + lnum = c->lpt_lnum; + offs = c->lpt_offs; + } + nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS); + if (!nnode) { + err = -ENOMEM; + goto out; + } + if (lnum == 0) { + /* + * This nnode was not written which just means that the LEB + * properties in the subtree below it describe empty LEBs. We + * make the nnode as though we had read it, which in fact means + * doing almost nothing. + */ + if (c->big_lpt) + nnode->num = calc_nnode_num_from_parent(c, parent, iip); + } else { + err = ubifs_leb_read(c, lnum, buf, offs, c->nnode_sz, 1); + if (err) { + if (err == -EBADMSG) + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + goto out; + } + err = ubifs_unpack_nnode(c, buf, nnode); + if (err) + goto out; + } + err = validate_nnode(c, nnode, parent, iip); + if (err) + goto out; + if (!c->big_lpt) + nnode->num = calc_nnode_num_from_parent(c, parent, iip); + if (parent) { + branch->nnode = nnode; + nnode->level = parent->level - 1; + } else { + c->nroot = nnode; + nnode->level = c->lpt_hght; + } + nnode->parent = parent; + nnode->iip = iip; + return 0; + +out: + ubifs_err(c, "error %d reading nnode at %d:%d", err, lnum, offs); + dump_stack(); + kfree(nnode); + return err; +} + +/** + * read_pnode - read a pnode from flash and link it to the tree in memory. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_pnode *pnode = NULL; + void *buf = c->lpt_nod_buf; + int err, lnum, offs; + + branch = &parent->nbranch[iip]; + lnum = branch->lnum; + offs = branch->offs; + pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS); + if (!pnode) + return -ENOMEM; + + if (lnum == 0) { + /* + * This pnode was not written which just means that the LEB + * properties in it describe empty LEBs. We make the pnode as + * though we had read it. + */ + int i; + + if (c->big_lpt) + pnode->num = calc_pnode_num_from_parent(c, parent, iip); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_lprops * const lprops = &pnode->lprops[i]; + + lprops->free = c->leb_size; + lprops->flags = ubifs_categorize_lprops(c, lprops); + } + } else { + err = ubifs_leb_read(c, lnum, buf, offs, c->pnode_sz, 1); + if (err) { + if (err == -EBADMSG) + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + goto out; + } + err = unpack_pnode(c, buf, pnode); + if (err) + goto out; + } + err = validate_pnode(c, pnode, parent, iip); + if (err) + goto out; + if (!c->big_lpt) + pnode->num = calc_pnode_num_from_parent(c, parent, iip); + branch->pnode = pnode; + pnode->parent = parent; + pnode->iip = iip; + set_pnode_lnum(c, pnode); + c->pnodes_have += 1; + return 0; + +out: + ubifs_err(c, "error %d reading pnode at %d:%d", err, lnum, offs); + ubifs_dump_pnode(c, pnode, parent, iip); + dump_stack(); + ubifs_err(c, "calc num: %d", calc_pnode_num_from_parent(c, parent, iip)); + kfree(pnode); + return err; +} + +/** + * read_ltab - read LPT's own lprops table. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int read_ltab(struct ubifs_info *c) +{ + int err; + void *buf; + + buf = vmalloc(c->ltab_sz); + if (!buf) + return -ENOMEM; + err = ubifs_leb_read(c, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz, 1); + if (err) { + if (err == -EBADMSG) + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + goto out; + } + err = unpack_ltab(c, buf); +out: + vfree(buf); + return err; +} + +/** + * read_lsave - read LPT's save table. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int read_lsave(struct ubifs_info *c) +{ + int err, i; + void *buf; + + buf = vmalloc(c->lsave_sz); + if (!buf) + return -ENOMEM; + err = ubifs_leb_read(c, c->lsave_lnum, buf, c->lsave_offs, + c->lsave_sz, 1); + if (err) { + if (err == -EBADMSG) + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + goto out; + } + err = unpack_lsave(c, buf); + if (err) + goto out; + for (i = 0; i < c->lsave_cnt; i++) { + int lnum = c->lsave[i]; + struct ubifs_lprops *lprops; + + /* + * Due to automatic resizing, the values in the lsave table + * could be beyond the volume size - just ignore them. + */ + if (lnum >= c->leb_cnt) + continue; + lprops = ubifs_lpt_lookup(c, lnum); + if (IS_ERR(lprops)) { + err = PTR_ERR(lprops); + goto out; + } + } +out: + vfree(buf); + return err; +} + +/** + * ubifs_get_nnode - get a nnode. + * @c: UBIFS file-system description object + * @parent: parent nnode (or NULL for the root) + * @iip: index in parent + * + * This function returns a pointer to the nnode on success or a negative error + * code on failure. + */ +struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_nnode *nnode; + int err; + + branch = &parent->nbranch[iip]; + nnode = branch->nnode; + if (nnode) + return nnode; + err = ubifs_read_nnode(c, parent, iip); + if (err) + return ERR_PTR(err); + return branch->nnode; +} + +/** + * ubifs_get_pnode - get a pnode. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * This function returns a pointer to the pnode on success or a negative error + * code on failure. + */ +struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_pnode *pnode; + int err; + + branch = &parent->nbranch[iip]; + pnode = branch->pnode; + if (pnode) + return pnode; + err = read_pnode(c, parent, iip); + if (err) + return ERR_PTR(err); + update_cats(c, branch->pnode); + return branch->pnode; +} + +/** + * ubifs_pnode_lookup - lookup a pnode in the LPT. + * @c: UBIFS file-system description object + * @i: pnode number (0 to (main_lebs - 1) / UBIFS_LPT_FANOUT) + * + * This function returns a pointer to the pnode on success or a negative + * error code on failure. + */ +struct ubifs_pnode *ubifs_pnode_lookup(struct ubifs_info *c, int i) +{ + int err, h, iip, shft; + struct ubifs_nnode *nnode; + + if (!c->nroot) { + err = ubifs_read_nnode(c, NULL, 0); + if (err) + return ERR_PTR(err); + } + i <<= UBIFS_LPT_FANOUT_SHIFT; + nnode = c->nroot; + shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; + for (h = 1; h < c->lpt_hght; h++) { + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + shft -= UBIFS_LPT_FANOUT_SHIFT; + nnode = ubifs_get_nnode(c, nnode, iip); + if (IS_ERR(nnode)) + return ERR_CAST(nnode); + } + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + return ubifs_get_pnode(c, nnode, iip); +} + +/** + * ubifs_lpt_lookup - lookup LEB properties in the LPT. + * @c: UBIFS file-system description object + * @lnum: LEB number to lookup + * + * This function returns a pointer to the LEB properties on success or a + * negative error code on failure. + */ +struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum) +{ + int i, iip; + struct ubifs_pnode *pnode; + + i = lnum - c->main_first; + pnode = ubifs_pnode_lookup(c, i >> UBIFS_LPT_FANOUT_SHIFT); + if (IS_ERR(pnode)) + return ERR_CAST(pnode); + iip = (i & (UBIFS_LPT_FANOUT - 1)); + dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum, + pnode->lprops[iip].free, pnode->lprops[iip].dirty, + pnode->lprops[iip].flags); + return &pnode->lprops[iip]; +} + +/** + * dirty_cow_nnode - ensure a nnode is not being committed. + * @c: UBIFS file-system description object + * @nnode: nnode to check + * + * Returns dirtied nnode on success or negative error code on failure. + */ +static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c, + struct ubifs_nnode *nnode) +{ + struct ubifs_nnode *n; + int i; + + if (!test_bit(COW_CNODE, &nnode->flags)) { + /* nnode is not being committed */ + if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) { + c->dirty_nn_cnt += 1; + ubifs_add_nnode_dirt(c, nnode); + } + return nnode; + } + + /* nnode is being committed, so copy it */ + n = kmemdup(nnode, sizeof(struct ubifs_nnode), GFP_NOFS); + if (unlikely(!n)) + return ERR_PTR(-ENOMEM); + + n->cnext = NULL; + __set_bit(DIRTY_CNODE, &n->flags); + __clear_bit(COW_CNODE, &n->flags); + + /* The children now have new parent */ + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_nbranch *branch = &n->nbranch[i]; + + if (branch->cnode) + branch->cnode->parent = n; + } + + ubifs_assert(c, !test_bit(OBSOLETE_CNODE, &nnode->flags)); + __set_bit(OBSOLETE_CNODE, &nnode->flags); + + c->dirty_nn_cnt += 1; + ubifs_add_nnode_dirt(c, nnode); + if (nnode->parent) + nnode->parent->nbranch[n->iip].nnode = n; + else + c->nroot = n; + return n; +} + +/** + * dirty_cow_pnode - ensure a pnode is not being committed. + * @c: UBIFS file-system description object + * @pnode: pnode to check + * + * Returns dirtied pnode on success or negative error code on failure. + */ +static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c, + struct ubifs_pnode *pnode) +{ + struct ubifs_pnode *p; + + if (!test_bit(COW_CNODE, &pnode->flags)) { + /* pnode is not being committed */ + if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) { + c->dirty_pn_cnt += 1; + add_pnode_dirt(c, pnode); + } + return pnode; + } + + /* pnode is being committed, so copy it */ + p = kmemdup(pnode, sizeof(struct ubifs_pnode), GFP_NOFS); + if (unlikely(!p)) + return ERR_PTR(-ENOMEM); + + p->cnext = NULL; + __set_bit(DIRTY_CNODE, &p->flags); + __clear_bit(COW_CNODE, &p->flags); + replace_cats(c, pnode, p); + + ubifs_assert(c, !test_bit(OBSOLETE_CNODE, &pnode->flags)); + __set_bit(OBSOLETE_CNODE, &pnode->flags); + + c->dirty_pn_cnt += 1; + add_pnode_dirt(c, pnode); + pnode->parent->nbranch[p->iip].pnode = p; + return p; +} + +/** + * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT. + * @c: UBIFS file-system description object + * @lnum: LEB number to lookup + * + * This function returns a pointer to the LEB properties on success or a + * negative error code on failure. + */ +struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum) +{ + int err, i, h, iip, shft; + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + + if (!c->nroot) { + err = ubifs_read_nnode(c, NULL, 0); + if (err) + return ERR_PTR(err); + } + nnode = c->nroot; + nnode = dirty_cow_nnode(c, nnode); + if (IS_ERR(nnode)) + return ERR_CAST(nnode); + i = lnum - c->main_first; + shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; + for (h = 1; h < c->lpt_hght; h++) { + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + shft -= UBIFS_LPT_FANOUT_SHIFT; + nnode = ubifs_get_nnode(c, nnode, iip); + if (IS_ERR(nnode)) + return ERR_CAST(nnode); + nnode = dirty_cow_nnode(c, nnode); + if (IS_ERR(nnode)) + return ERR_CAST(nnode); + } + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + pnode = ubifs_get_pnode(c, nnode, iip); + if (IS_ERR(pnode)) + return ERR_CAST(pnode); + pnode = dirty_cow_pnode(c, pnode); + if (IS_ERR(pnode)) + return ERR_CAST(pnode); + iip = (i & (UBIFS_LPT_FANOUT - 1)); + dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum, + pnode->lprops[iip].free, pnode->lprops[iip].dirty, + pnode->lprops[iip].flags); + ubifs_assert(c, test_bit(DIRTY_CNODE, &pnode->flags)); + return &pnode->lprops[iip]; +} + +/** + * ubifs_lpt_calc_hash - Calculate hash of the LPT pnodes + * @c: UBIFS file-system description object + * @hash: the returned hash of the LPT pnodes + * + * This function iterates over the LPT pnodes and creates a hash over them. + * Returns 0 for success or a negative error code otherwise. + */ +int ubifs_lpt_calc_hash(struct ubifs_info *c, u8 *hash) +{ + struct ubifs_nnode *nnode, *nn; + struct ubifs_cnode *cnode; + struct shash_desc *desc; + int iip = 0, i; + int bufsiz = max_t(int, c->nnode_sz, c->pnode_sz); + void *buf; + int err; + + if (!ubifs_authenticated(c)) + return 0; + + if (!c->nroot) { + err = ubifs_read_nnode(c, NULL, 0); + if (err) + return err; + } + + desc = ubifs_hash_get_desc(c); + if (IS_ERR(desc)) + return PTR_ERR(desc); + + buf = kmalloc(bufsiz, GFP_NOFS); + if (!buf) { + err = -ENOMEM; + goto out; + } + + cnode = (struct ubifs_cnode *)c->nroot; + + while (cnode) { + nnode = cnode->parent; + nn = (struct ubifs_nnode *)cnode; + if (cnode->level > 1) { + while (iip < UBIFS_LPT_FANOUT) { + if (nn->nbranch[iip].lnum == 0) { + /* Go right */ + iip++; + continue; + } + + nnode = ubifs_get_nnode(c, nn, iip); + if (IS_ERR(nnode)) { + err = PTR_ERR(nnode); + goto out; + } + + /* Go down */ + iip = 0; + cnode = (struct ubifs_cnode *)nnode; + break; + } + if (iip < UBIFS_LPT_FANOUT) + continue; + } else { + struct ubifs_pnode *pnode; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (nn->nbranch[i].lnum == 0) + continue; + pnode = ubifs_get_pnode(c, nn, i); + if (IS_ERR(pnode)) { + err = PTR_ERR(pnode); + goto out; + } + + ubifs_pack_pnode(c, buf, pnode); + err = ubifs_shash_update(c, desc, buf, + c->pnode_sz); + if (err) + goto out; + } + } + /* Go up and to the right */ + iip = cnode->iip + 1; + cnode = (struct ubifs_cnode *)nnode; + } + + err = ubifs_shash_final(c, desc, hash); +out: + kfree(desc); + kfree(buf); + + return err; +} + +/** + * lpt_check_hash - check the hash of the LPT. + * @c: UBIFS file-system description object + * + * This function calculates a hash over all pnodes in the LPT and compares it with + * the hash stored in the master node. Returns %0 on success and a negative error + * code on failure. + */ +static int lpt_check_hash(struct ubifs_info *c) +{ + int err; + u8 hash[UBIFS_HASH_ARR_SZ]; + + if (!ubifs_authenticated(c)) + return 0; + + err = ubifs_lpt_calc_hash(c, hash); + if (err) + return err; + + if (ubifs_check_hash(c, c->mst_node->hash_lpt, hash)) { + err = -EPERM; + ubifs_err(c, "Failed to authenticate LPT"); + } else { + err = 0; + } + + return err; +} + +/** + * lpt_init_rd - initialize the LPT for reading. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int lpt_init_rd(struct ubifs_info *c) +{ + int err, i; + + c->ltab = vmalloc(array_size(sizeof(struct ubifs_lpt_lprops), + c->lpt_lebs)); + if (!c->ltab) + return -ENOMEM; + + i = max_t(int, c->nnode_sz, c->pnode_sz); + c->lpt_nod_buf = kmalloc(i, GFP_KERNEL); + if (!c->lpt_nod_buf) + return -ENOMEM; + + for (i = 0; i < LPROPS_HEAP_CNT; i++) { + c->lpt_heap[i].arr = kmalloc_array(LPT_HEAP_SZ, + sizeof(void *), + GFP_KERNEL); + if (!c->lpt_heap[i].arr) + return -ENOMEM; + c->lpt_heap[i].cnt = 0; + c->lpt_heap[i].max_cnt = LPT_HEAP_SZ; + } + + c->dirty_idx.arr = kmalloc_array(LPT_HEAP_SZ, sizeof(void *), + GFP_KERNEL); + if (!c->dirty_idx.arr) + return -ENOMEM; + c->dirty_idx.cnt = 0; + c->dirty_idx.max_cnt = LPT_HEAP_SZ; + + err = read_ltab(c); + if (err) { + if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) && + can_ignore_failure_callback(c, FR_LPT_CORRUPTED)) + err = 0; + else + return err; + } + + err = lpt_check_hash(c); + if (err) + return err; + + dbg_lp("space_bits %d", c->space_bits); + dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits); + dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits); + dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits); + dbg_lp("pcnt_bits %d", c->pcnt_bits); + dbg_lp("lnum_bits %d", c->lnum_bits); + dbg_lp("pnode_sz %d", c->pnode_sz); + dbg_lp("nnode_sz %d", c->nnode_sz); + dbg_lp("ltab_sz %d", c->ltab_sz); + dbg_lp("lsave_sz %d", c->lsave_sz); + dbg_lp("lsave_cnt %d", c->lsave_cnt); + dbg_lp("lpt_hght %d", c->lpt_hght); + dbg_lp("big_lpt %u", c->big_lpt); + dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs); + dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs); + dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs); + if (c->big_lpt) + dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs); + + return 0; +} + +/** + * lpt_init_wr - initialize the LPT for writing. + * @c: UBIFS file-system description object + * + * 'lpt_init_rd()' must have been called already. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int lpt_init_wr(struct ubifs_info *c) +{ + int err, i; + + c->ltab_cmt = vmalloc(array_size(sizeof(struct ubifs_lpt_lprops), + c->lpt_lebs)); + if (!c->ltab_cmt) + return -ENOMEM; + + c->lpt_buf = vmalloc(c->leb_size); + if (!c->lpt_buf) + return -ENOMEM; + + if (c->big_lpt) { + c->lsave = kmalloc_array(c->lsave_cnt, sizeof(int), GFP_NOFS); + if (!c->lsave) + return -ENOMEM; + err = read_lsave(c); + if (err) { + if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) && + can_ignore_failure_callback(c, FR_LPT_CORRUPTED)) + err = 0; + else + return err; + } + } + + for (i = 0; i < c->lpt_lebs; i++) + if (c->ltab[i].free == c->leb_size) { + err = ubifs_leb_unmap(c, i + c->lpt_first); + if (err) + return err; + } + + return 0; +} + +/** + * ubifs_lpt_init - initialize the LPT. + * @c: UBIFS file-system description object + * @rd: whether to initialize lpt for reading + * @wr: whether to initialize lpt for writing + * + * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true + * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is + * true. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr) +{ + int err; + + if (rd) { + err = lpt_init_rd(c); + if (err) + goto out_err; + } + + if (wr) { + err = lpt_init_wr(c); + if (err) + goto out_err; + } + + return 0; + +out_err: + if (wr) + ubifs_lpt_free(c, 1); + if (rd) + ubifs_lpt_free(c, 0); + return err; +} + +/** + * struct lpt_scan_node - somewhere to put nodes while we scan LPT. + * @nnode: where to keep a nnode + * @pnode: where to keep a pnode + * @cnode: where to keep a cnode + * @in_tree: is the node in the tree in memory + * @ptr: union of node pointers + * @ptr.nnode: pointer to the nnode (if it is an nnode) which may be here or in + * the tree + * @ptr.pnode: ditto for pnode + * @ptr.cnode: ditto for cnode + */ +struct lpt_scan_node { + union { + struct ubifs_nnode nnode; + struct ubifs_pnode pnode; + struct ubifs_cnode cnode; + }; + int in_tree; + union { + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + struct ubifs_cnode *cnode; + } ptr; +}; + +/** + * scan_get_nnode - for the scan, get a nnode from either the tree or flash. + * @c: the UBIFS file-system description object + * @path: where to put the nnode + * @parent: parent of the nnode + * @iip: index in parent of the nnode + * + * This function returns a pointer to the nnode on success or a negative error + * code on failure. + */ +static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c, + struct lpt_scan_node *path, + struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_nnode *nnode; + void *buf = c->lpt_nod_buf; + int err; + + branch = &parent->nbranch[iip]; + nnode = branch->nnode; + if (nnode) { + path->in_tree = 1; + path->ptr.nnode = nnode; + return nnode; + } + nnode = &path->nnode; + path->in_tree = 0; + path->ptr.nnode = nnode; + memset(nnode, 0, sizeof(struct ubifs_nnode)); + if (branch->lnum == 0) { + /* + * This nnode was not written which just means that the LEB + * properties in the subtree below it describe empty LEBs. We + * make the nnode as though we had read it, which in fact means + * doing almost nothing. + */ + if (c->big_lpt) + nnode->num = calc_nnode_num_from_parent(c, parent, iip); + } else { + err = ubifs_leb_read(c, branch->lnum, buf, branch->offs, + c->nnode_sz, 1); + if (err) { + if (err == -EBADMSG) + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + return ERR_PTR(err); + } + err = ubifs_unpack_nnode(c, buf, nnode); + if (err) + return ERR_PTR(err); + } + err = validate_nnode(c, nnode, parent, iip); + if (err) + return ERR_PTR(err); + if (!c->big_lpt) + nnode->num = calc_nnode_num_from_parent(c, parent, iip); + nnode->level = parent->level - 1; + nnode->parent = parent; + nnode->iip = iip; + return nnode; +} + +/** + * scan_get_pnode - for the scan, get a pnode from either the tree or flash. + * @c: the UBIFS file-system description object + * @path: where to put the pnode + * @parent: parent of the pnode + * @iip: index in parent of the pnode + * + * This function returns a pointer to the pnode on success or a negative error + * code on failure. + */ +static struct ubifs_pnode *scan_get_pnode(struct ubifs_info *c, + struct lpt_scan_node *path, + struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_pnode *pnode; + void *buf = c->lpt_nod_buf; + int err; + + branch = &parent->nbranch[iip]; + pnode = branch->pnode; + if (pnode) { + path->in_tree = 1; + path->ptr.pnode = pnode; + return pnode; + } + pnode = &path->pnode; + path->in_tree = 0; + path->ptr.pnode = pnode; + memset(pnode, 0, sizeof(struct ubifs_pnode)); + if (branch->lnum == 0) { + /* + * This pnode was not written which just means that the LEB + * properties in it describe empty LEBs. We make the pnode as + * though we had read it. + */ + int i; + + if (c->big_lpt) + pnode->num = calc_pnode_num_from_parent(c, parent, iip); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_lprops * const lprops = &pnode->lprops[i]; + + lprops->free = c->leb_size; + lprops->flags = ubifs_categorize_lprops(c, lprops); + } + } else { + ubifs_assert(c, branch->lnum >= c->lpt_first && + branch->lnum <= c->lpt_last); + ubifs_assert(c, branch->offs >= 0 && branch->offs < c->leb_size); + err = ubifs_leb_read(c, branch->lnum, buf, branch->offs, + c->pnode_sz, 1); + if (err) { + if (err == -EBADMSG) + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + return ERR_PTR(err); + } + err = unpack_pnode(c, buf, pnode); + if (err) + return ERR_PTR(err); + } + err = validate_pnode(c, pnode, parent, iip); + if (err) + return ERR_PTR(err); + if (!c->big_lpt) + pnode->num = calc_pnode_num_from_parent(c, parent, iip); + pnode->parent = parent; + pnode->iip = iip; + set_pnode_lnum(c, pnode); + return pnode; +} + +/** + * ubifs_lpt_scan_nolock - scan the LPT. + * @c: the UBIFS file-system description object + * @start_lnum: LEB number from which to start scanning + * @end_lnum: LEB number at which to stop scanning + * @scan_cb: callback function called for each lprops + * @data: data to be passed to the callback function + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum, + ubifs_lpt_scan_callback scan_cb, void *data) +{ + int err = 0, i, h, iip, shft; + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + struct lpt_scan_node *path; + + if (start_lnum == -1) { + start_lnum = end_lnum + 1; + if (start_lnum >= c->leb_cnt) + start_lnum = c->main_first; + } + + ubifs_assert(c, start_lnum >= c->main_first && start_lnum < c->leb_cnt); + ubifs_assert(c, end_lnum >= c->main_first && end_lnum < c->leb_cnt); + + if (!c->nroot) { + err = ubifs_read_nnode(c, NULL, 0); + if (err) + return err; + } + + path = kmalloc_array(c->lpt_hght + 1, sizeof(struct lpt_scan_node), + GFP_NOFS); + if (!path) + return -ENOMEM; + + path[0].ptr.nnode = c->nroot; + path[0].in_tree = 1; +again: + /* Descend to the pnode containing start_lnum */ + nnode = c->nroot; + i = start_lnum - c->main_first; + shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; + for (h = 1; h < c->lpt_hght; h++) { + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + shft -= UBIFS_LPT_FANOUT_SHIFT; + nnode = scan_get_nnode(c, path + h, nnode, iip); + if (IS_ERR(nnode)) { + err = PTR_ERR(nnode); + goto out; + } + } + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + pnode = scan_get_pnode(c, path + h, nnode, iip); + if (IS_ERR(pnode)) { + err = PTR_ERR(pnode); + goto out; + } + iip = (i & (UBIFS_LPT_FANOUT - 1)); + + /* Loop for each lprops */ + while (1) { + struct ubifs_lprops *lprops = &pnode->lprops[iip]; + int ret, lnum = lprops->lnum; + + ret = scan_cb(c, lprops, path[h].in_tree, data); + if (ret < 0) { + err = ret; + goto out; + } + if (ret & LPT_SCAN_ADD) { + /* Add all the nodes in path to the tree in memory */ + for (h = 1; h < c->lpt_hght; h++) { + const size_t sz = sizeof(struct ubifs_nnode); + struct ubifs_nnode *parent; + + if (path[h].in_tree) + continue; + nnode = kmemdup(&path[h].nnode, sz, GFP_NOFS); + if (!nnode) { + err = -ENOMEM; + goto out; + } + parent = nnode->parent; + parent->nbranch[nnode->iip].nnode = nnode; + path[h].ptr.nnode = nnode; + path[h].in_tree = 1; + path[h + 1].cnode.parent = nnode; + } + if (path[h].in_tree) + ubifs_ensure_cat(c, lprops); + else { + const size_t sz = sizeof(struct ubifs_pnode); + struct ubifs_nnode *parent; + + pnode = kmemdup(&path[h].pnode, sz, GFP_NOFS); + if (!pnode) { + err = -ENOMEM; + goto out; + } + parent = pnode->parent; + parent->nbranch[pnode->iip].pnode = pnode; + path[h].ptr.pnode = pnode; + path[h].in_tree = 1; + update_cats(c, pnode); + c->pnodes_have += 1; + } + err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *) + c->nroot, 0, 0); + if (err) + goto out; + err = dbg_check_cats(c); + if (err) + goto out; + } + if (ret & LPT_SCAN_STOP) { + err = 0; + break; + } + /* Get the next lprops */ + if (lnum == end_lnum) { + /* + * We got to the end without finding what we were + * looking for + */ + err = -ENOSPC; + goto out; + } + if (lnum + 1 >= c->leb_cnt) { + /* Wrap-around to the beginning */ + start_lnum = c->main_first; + goto again; + } + if (iip + 1 < UBIFS_LPT_FANOUT) { + /* Next lprops is in the same pnode */ + iip += 1; + continue; + } + /* We need to get the next pnode. Go up until we can go right */ + iip = pnode->iip; + while (1) { + h -= 1; + ubifs_assert(c, h >= 0); + nnode = path[h].ptr.nnode; + if (iip + 1 < UBIFS_LPT_FANOUT) + break; + iip = nnode->iip; + } + /* Go right */ + iip += 1; + /* Descend to the pnode */ + h += 1; + for (; h < c->lpt_hght; h++) { + nnode = scan_get_nnode(c, path + h, nnode, iip); + if (IS_ERR(nnode)) { + err = PTR_ERR(nnode); + goto out; + } + iip = 0; + } + pnode = scan_get_pnode(c, path + h, nnode, iip); + if (IS_ERR(pnode)) { + err = PTR_ERR(pnode); + goto out; + } + iip = 0; + } +out: + kfree(path); + return err; +} diff --git a/ubifs-utils/libubifs/lpt_commit.c b/ubifs-utils/libubifs/lpt_commit.c new file mode 100644 index 0000000..79f7b14 --- /dev/null +++ b/ubifs-utils/libubifs/lpt_commit.c @@ -0,0 +1,1812 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements commit-related functionality of the LEB properties + * subsystem. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "crc16.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "misc.h" + +static int dbg_populate_lsave(struct ubifs_info *c); + +/** + * first_dirty_cnode - find first dirty cnode. + * @c: UBIFS file-system description object + * @nnode: nnode at which to start + * + * This function returns the first dirty cnode or %NULL if there is not one. + */ +static struct ubifs_cnode *first_dirty_cnode(const struct ubifs_info *c, struct ubifs_nnode *nnode) +{ + ubifs_assert(c, nnode); + while (1) { + int i, cont = 0; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_cnode *cnode; + + cnode = nnode->nbranch[i].cnode; + if (cnode && + test_bit(DIRTY_CNODE, &cnode->flags)) { + if (cnode->level == 0) + return cnode; + nnode = (struct ubifs_nnode *)cnode; + cont = 1; + break; + } + } + if (!cont) + return (struct ubifs_cnode *)nnode; + } +} + +/** + * next_dirty_cnode - find next dirty cnode. + * @c: UBIFS file-system description object + * @cnode: cnode from which to begin searching + * + * This function returns the next dirty cnode or %NULL if there is not one. + */ +static struct ubifs_cnode *next_dirty_cnode(const struct ubifs_info *c, struct ubifs_cnode *cnode) +{ + struct ubifs_nnode *nnode; + int i; + + ubifs_assert(c, cnode); + nnode = cnode->parent; + if (!nnode) + return NULL; + for (i = cnode->iip + 1; i < UBIFS_LPT_FANOUT; i++) { + cnode = nnode->nbranch[i].cnode; + if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) { + if (cnode->level == 0) + return cnode; /* cnode is a pnode */ + /* cnode is a nnode */ + return first_dirty_cnode(c, (struct ubifs_nnode *)cnode); + } + } + return (struct ubifs_cnode *)nnode; +} + +/** + * get_cnodes_to_commit - create list of dirty cnodes to commit. + * @c: UBIFS file-system description object + * + * This function returns the number of cnodes to commit. + */ +static int get_cnodes_to_commit(struct ubifs_info *c) +{ + struct ubifs_cnode *cnode, *cnext; + int cnt = 0; + + if (!c->nroot) + return 0; + + if (!test_bit(DIRTY_CNODE, &c->nroot->flags)) + return 0; + + c->lpt_cnext = first_dirty_cnode(c, c->nroot); + cnode = c->lpt_cnext; + if (!cnode) + return 0; + cnt += 1; + while (1) { + ubifs_assert(c, !test_bit(COW_CNODE, &cnode->flags)); + __set_bit(COW_CNODE, &cnode->flags); + cnext = next_dirty_cnode(c, cnode); + if (!cnext) { + cnode->cnext = c->lpt_cnext; + break; + } + cnode->cnext = cnext; + cnode = cnext; + cnt += 1; + } + dbg_cmt("committing %d cnodes", cnt); + dbg_lp("committing %d cnodes", cnt); + ubifs_assert(c, cnt == c->dirty_nn_cnt + c->dirty_pn_cnt); + return cnt; +} + +/** + * upd_ltab - update LPT LEB properties. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @free: amount of free space + * @dirty: amount of dirty space to add + */ +static void upd_ltab(struct ubifs_info *c, int lnum, int free, int dirty) +{ + dbg_lp("LEB %d free %d dirty %d to %d +%d", + lnum, c->ltab[lnum - c->lpt_first].free, + c->ltab[lnum - c->lpt_first].dirty, free, dirty); + ubifs_assert(c, lnum >= c->lpt_first && lnum <= c->lpt_last); + c->ltab[lnum - c->lpt_first].free = free; + c->ltab[lnum - c->lpt_first].dirty += dirty; +} + +/** + * alloc_lpt_leb - allocate an LPT LEB that is empty. + * @c: UBIFS file-system description object + * @lnum: LEB number is passed and returned here + * + * This function finds the next empty LEB in the ltab starting from @lnum. If a + * an empty LEB is found it is returned in @lnum and the function returns %0. + * Otherwise the function returns -ENOSPC. Note however, that LPT is designed + * never to run out of space. + */ +static int alloc_lpt_leb(struct ubifs_info *c, int *lnum) +{ + int i, n; + + n = *lnum - c->lpt_first + 1; + for (i = n; i < c->lpt_lebs; i++) { + if (c->ltab[i].tgc || c->ltab[i].cmt) + continue; + if (c->ltab[i].free == c->leb_size) { + c->ltab[i].cmt = 1; + *lnum = i + c->lpt_first; + return 0; + } + } + + for (i = 0; i < n; i++) { + if (c->ltab[i].tgc || c->ltab[i].cmt) + continue; + if (c->ltab[i].free == c->leb_size) { + c->ltab[i].cmt = 1; + *lnum = i + c->lpt_first; + return 0; + } + } + return -ENOSPC; +} + +/** + * layout_cnodes - layout cnodes for commit. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int layout_cnodes(struct ubifs_info *c) +{ + int lnum, offs, len, alen, done_lsave, done_ltab, err; + struct ubifs_cnode *cnode; + + err = dbg_chk_lpt_sz(c, 0, 0); + if (err) + return err; + cnode = c->lpt_cnext; + if (!cnode) + return 0; + lnum = c->nhead_lnum; + offs = c->nhead_offs; + /* Try to place lsave and ltab nicely */ + done_lsave = !c->big_lpt; + done_ltab = 0; + if (!done_lsave && offs + c->lsave_sz <= c->leb_size) { + done_lsave = 1; + c->lsave_lnum = lnum; + c->lsave_offs = offs; + offs += c->lsave_sz; + dbg_chk_lpt_sz(c, 1, c->lsave_sz); + } + + if (offs + c->ltab_sz <= c->leb_size) { + done_ltab = 1; + c->ltab_lnum = lnum; + c->ltab_offs = offs; + offs += c->ltab_sz; + dbg_chk_lpt_sz(c, 1, c->ltab_sz); + } + + do { + if (cnode->level) { + len = c->nnode_sz; + c->dirty_nn_cnt -= 1; + } else { + len = c->pnode_sz; + c->dirty_pn_cnt -= 1; + } + while (offs + len > c->leb_size) { + alen = ALIGN(offs, c->min_io_size); + upd_ltab(c, lnum, c->leb_size - alen, alen - offs); + dbg_chk_lpt_sz(c, 2, c->leb_size - offs); + err = alloc_lpt_leb(c, &lnum); + if (err) + goto no_space; + offs = 0; + ubifs_assert(c, lnum >= c->lpt_first && + lnum <= c->lpt_last); + /* Try to place lsave and ltab nicely */ + if (!done_lsave) { + done_lsave = 1; + c->lsave_lnum = lnum; + c->lsave_offs = offs; + offs += c->lsave_sz; + dbg_chk_lpt_sz(c, 1, c->lsave_sz); + continue; + } + if (!done_ltab) { + done_ltab = 1; + c->ltab_lnum = lnum; + c->ltab_offs = offs; + offs += c->ltab_sz; + dbg_chk_lpt_sz(c, 1, c->ltab_sz); + continue; + } + break; + } + if (cnode->parent) { + cnode->parent->nbranch[cnode->iip].lnum = lnum; + cnode->parent->nbranch[cnode->iip].offs = offs; + } else { + c->lpt_lnum = lnum; + c->lpt_offs = offs; + } + offs += len; + dbg_chk_lpt_sz(c, 1, len); + cnode = cnode->cnext; + } while (cnode && cnode != c->lpt_cnext); + + /* Make sure to place LPT's save table */ + if (!done_lsave) { + if (offs + c->lsave_sz > c->leb_size) { + alen = ALIGN(offs, c->min_io_size); + upd_ltab(c, lnum, c->leb_size - alen, alen - offs); + dbg_chk_lpt_sz(c, 2, c->leb_size - offs); + err = alloc_lpt_leb(c, &lnum); + if (err) + goto no_space; + offs = 0; + ubifs_assert(c, lnum >= c->lpt_first && + lnum <= c->lpt_last); + } + done_lsave = 1; + c->lsave_lnum = lnum; + c->lsave_offs = offs; + offs += c->lsave_sz; + dbg_chk_lpt_sz(c, 1, c->lsave_sz); + } + + /* Make sure to place LPT's own lprops table */ + if (!done_ltab) { + if (offs + c->ltab_sz > c->leb_size) { + alen = ALIGN(offs, c->min_io_size); + upd_ltab(c, lnum, c->leb_size - alen, alen - offs); + dbg_chk_lpt_sz(c, 2, c->leb_size - offs); + err = alloc_lpt_leb(c, &lnum); + if (err) + goto no_space; + offs = 0; + ubifs_assert(c, lnum >= c->lpt_first && + lnum <= c->lpt_last); + } + c->ltab_lnum = lnum; + c->ltab_offs = offs; + offs += c->ltab_sz; + dbg_chk_lpt_sz(c, 1, c->ltab_sz); + } + + alen = ALIGN(offs, c->min_io_size); + upd_ltab(c, lnum, c->leb_size - alen, alen - offs); + dbg_chk_lpt_sz(c, 4, alen - offs); + err = dbg_chk_lpt_sz(c, 3, alen); + if (err) + return err; + return 0; + +no_space: + ubifs_err(c, "LPT out of space at LEB %d:%d needing %d, done_ltab %d, done_lsave %d", + lnum, offs, len, done_ltab, done_lsave); + ubifs_dump_lpt_info(c); + ubifs_dump_lpt_lebs(c); + dump_stack(); + return err; +} + +/** + * realloc_lpt_leb - allocate an LPT LEB that is empty. + * @c: UBIFS file-system description object + * @lnum: LEB number is passed and returned here + * + * This function duplicates exactly the results of the function alloc_lpt_leb. + * It is used during end commit to reallocate the same LEB numbers that were + * allocated by alloc_lpt_leb during start commit. + * + * This function finds the next LEB that was allocated by the alloc_lpt_leb + * function starting from @lnum. If a LEB is found it is returned in @lnum and + * the function returns %0. Otherwise the function returns -ENOSPC. + * Note however, that LPT is designed never to run out of space. + */ +static int realloc_lpt_leb(struct ubifs_info *c, int *lnum) +{ + int i, n; + + n = *lnum - c->lpt_first + 1; + for (i = n; i < c->lpt_lebs; i++) + if (c->ltab[i].cmt) { + c->ltab[i].cmt = 0; + *lnum = i + c->lpt_first; + return 0; + } + + for (i = 0; i < n; i++) + if (c->ltab[i].cmt) { + c->ltab[i].cmt = 0; + *lnum = i + c->lpt_first; + return 0; + } + return -ENOSPC; +} + +/** + * write_cnodes - write cnodes for commit. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int write_cnodes(struct ubifs_info *c) +{ + int lnum, offs, len, from, err, wlen, alen, done_ltab, done_lsave; + struct ubifs_cnode *cnode; + void *buf = c->lpt_buf; + + cnode = c->lpt_cnext; + if (!cnode) + return 0; + lnum = c->nhead_lnum; + offs = c->nhead_offs; + from = offs; + /* Ensure empty LEB is unmapped */ + if (offs == 0) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + /* Try to place lsave and ltab nicely */ + done_lsave = !c->big_lpt; + done_ltab = 0; + if (!done_lsave && offs + c->lsave_sz <= c->leb_size) { + done_lsave = 1; + ubifs_pack_lsave(c, buf + offs, c->lsave); + offs += c->lsave_sz; + dbg_chk_lpt_sz(c, 1, c->lsave_sz); + } + + if (offs + c->ltab_sz <= c->leb_size) { + done_ltab = 1; + ubifs_pack_ltab(c, buf + offs, c->ltab_cmt); + offs += c->ltab_sz; + dbg_chk_lpt_sz(c, 1, c->ltab_sz); + } + + /* Loop for each cnode */ + do { + if (cnode->level) + len = c->nnode_sz; + else + len = c->pnode_sz; + while (offs + len > c->leb_size) { + wlen = offs - from; + if (wlen) { + alen = ALIGN(wlen, c->min_io_size); + memset(buf + offs, 0xff, alen - wlen); + err = ubifs_leb_write(c, lnum, buf + from, from, + alen); + if (err) + return err; + } + dbg_chk_lpt_sz(c, 2, c->leb_size - offs); + err = realloc_lpt_leb(c, &lnum); + if (err) + goto no_space; + offs = from = 0; + ubifs_assert(c, lnum >= c->lpt_first && + lnum <= c->lpt_last); + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + /* Try to place lsave and ltab nicely */ + if (!done_lsave) { + done_lsave = 1; + ubifs_pack_lsave(c, buf + offs, c->lsave); + offs += c->lsave_sz; + dbg_chk_lpt_sz(c, 1, c->lsave_sz); + continue; + } + if (!done_ltab) { + done_ltab = 1; + ubifs_pack_ltab(c, buf + offs, c->ltab_cmt); + offs += c->ltab_sz; + dbg_chk_lpt_sz(c, 1, c->ltab_sz); + continue; + } + break; + } + if (cnode->level) + ubifs_pack_nnode(c, buf + offs, + (struct ubifs_nnode *)cnode); + else + ubifs_pack_pnode(c, buf + offs, + (struct ubifs_pnode *)cnode); + /* + * The reason for the barriers is the same as in case of TNC. + * See comment in 'write_index()'. 'dirty_cow_nnode()' and + * 'dirty_cow_pnode()' are the functions for which this is + * important. + */ + clear_bit(DIRTY_CNODE, &cnode->flags); + smp_mb__before_atomic(); + clear_bit(COW_CNODE, &cnode->flags); + smp_mb__after_atomic(); + offs += len; + dbg_chk_lpt_sz(c, 1, len); + cnode = cnode->cnext; + } while (cnode && cnode != c->lpt_cnext); + + /* Make sure to place LPT's save table */ + if (!done_lsave) { + if (offs + c->lsave_sz > c->leb_size) { + wlen = offs - from; + alen = ALIGN(wlen, c->min_io_size); + memset(buf + offs, 0xff, alen - wlen); + err = ubifs_leb_write(c, lnum, buf + from, from, alen); + if (err) + return err; + dbg_chk_lpt_sz(c, 2, c->leb_size - offs); + err = realloc_lpt_leb(c, &lnum); + if (err) + goto no_space; + offs = from = 0; + ubifs_assert(c, lnum >= c->lpt_first && + lnum <= c->lpt_last); + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + done_lsave = 1; + ubifs_pack_lsave(c, buf + offs, c->lsave); + offs += c->lsave_sz; + dbg_chk_lpt_sz(c, 1, c->lsave_sz); + } + + /* Make sure to place LPT's own lprops table */ + if (!done_ltab) { + if (offs + c->ltab_sz > c->leb_size) { + wlen = offs - from; + alen = ALIGN(wlen, c->min_io_size); + memset(buf + offs, 0xff, alen - wlen); + err = ubifs_leb_write(c, lnum, buf + from, from, alen); + if (err) + return err; + dbg_chk_lpt_sz(c, 2, c->leb_size - offs); + err = realloc_lpt_leb(c, &lnum); + if (err) + goto no_space; + offs = from = 0; + ubifs_assert(c, lnum >= c->lpt_first && + lnum <= c->lpt_last); + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + ubifs_pack_ltab(c, buf + offs, c->ltab_cmt); + offs += c->ltab_sz; + dbg_chk_lpt_sz(c, 1, c->ltab_sz); + } + + /* Write remaining data in buffer */ + wlen = offs - from; + alen = ALIGN(wlen, c->min_io_size); + memset(buf + offs, 0xff, alen - wlen); + err = ubifs_leb_write(c, lnum, buf + from, from, alen); + if (err) + return err; + + dbg_chk_lpt_sz(c, 4, alen - wlen); + err = dbg_chk_lpt_sz(c, 3, ALIGN(offs, c->min_io_size)); + if (err) + return err; + + c->nhead_lnum = lnum; + c->nhead_offs = ALIGN(offs, c->min_io_size); + + dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs); + dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs); + dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs); + if (c->big_lpt) + dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs); + + return 0; + +no_space: + ubifs_err(c, "LPT out of space mismatch at LEB %d:%d needing %d, done_ltab %d, done_lsave %d", + lnum, offs, len, done_ltab, done_lsave); + ubifs_dump_lpt_info(c); + ubifs_dump_lpt_lebs(c); + dump_stack(); + return err; +} + +/** + * ubifs_find_next_pnode - find next pnode. + * @c: UBIFS file-system description object + * @pnode: pnode + * + * This function returns the next pnode or %NULL if there are no more pnodes. + * Note that pnodes that have never been written (lnum == 0) are skipped. + */ +struct ubifs_pnode *ubifs_find_next_pnode(struct ubifs_info *c, + struct ubifs_pnode *pnode) +{ + struct ubifs_nnode *nnode; + int iip; + + /* Try to go right */ + nnode = pnode->parent; + for (iip = pnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) { + if (nnode->nbranch[iip].lnum) + return ubifs_get_pnode(c, nnode, iip); + } + + /* Go up while can't go right */ + do { + iip = nnode->iip + 1; + nnode = nnode->parent; + if (!nnode) + return NULL; + for (; iip < UBIFS_LPT_FANOUT; iip++) { + if (nnode->nbranch[iip].lnum) + break; + } + } while (iip >= UBIFS_LPT_FANOUT); + + /* Go right */ + nnode = ubifs_get_nnode(c, nnode, iip); + if (IS_ERR(nnode)) + return ERR_CAST(nnode); + + /* Go down to level 1 */ + while (nnode->level > 1) { + for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) { + if (nnode->nbranch[iip].lnum) + break; + } + if (iip >= UBIFS_LPT_FANOUT) { + /* + * Should not happen, but we need to keep going + * if it does. + */ + iip = 0; + } + nnode = ubifs_get_nnode(c, nnode, iip); + if (IS_ERR(nnode)) + return ERR_CAST(nnode); + } + + for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) + if (nnode->nbranch[iip].lnum) + break; + if (iip >= UBIFS_LPT_FANOUT) + /* Should not happen, but we need to keep going if it does */ + iip = 0; + return ubifs_get_pnode(c, nnode, iip); +} + +/** + * add_pnode_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @pnode: pnode for which to add dirt + */ +static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum, + c->pnode_sz); +} + +/** + * ubifs_make_nnode_dirty - mark a nnode dirty. + * @c: UBIFS file-system description object + * @nnode: nnode to mark dirty + */ +void ubifs_make_nnode_dirty(struct ubifs_info *c, struct ubifs_nnode *nnode) +{ + while (nnode) { + if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) { + c->dirty_nn_cnt += 1; + ubifs_add_nnode_dirt(c, nnode); + nnode = nnode->parent; + } else + break; + } +} + +/** + * ubifs_make_pnode_dirty - mark a pnode dirty. + * @c: UBIFS file-system description object + * @pnode: pnode to mark dirty + */ +void ubifs_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + /* Assumes cnext list is empty i.e. not called during commit */ + if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) { + c->dirty_pn_cnt += 1; + add_pnode_dirt(c, pnode); + /* Mark parent and ancestors dirty too */ + ubifs_make_nnode_dirty(c, pnode->parent); + } +} + +/** + * make_tree_dirty - mark the entire LEB properties tree dirty. + * @c: UBIFS file-system description object + * + * This function is used by the "small" LPT model to cause the entire LEB + * properties tree to be written. The "small" LPT model does not use LPT + * garbage collection because it is more efficient to write the entire tree + * (because it is small). + * + * This function returns %0 on success and a negative error code on failure. + */ +static int make_tree_dirty(struct ubifs_info *c) +{ + struct ubifs_pnode *pnode; + + pnode = ubifs_pnode_lookup(c, 0); + if (IS_ERR(pnode)) + return PTR_ERR(pnode); + + while (pnode) { + ubifs_make_pnode_dirty(c, pnode); + pnode = ubifs_find_next_pnode(c, pnode); + if (IS_ERR(pnode)) + return PTR_ERR(pnode); + } + return 0; +} + +/** + * need_write_all - determine if the LPT area is running out of free space. + * @c: UBIFS file-system description object + * + * This function returns %1 if the LPT area is running out of free space and %0 + * if it is not. + */ +static int need_write_all(struct ubifs_info *c) +{ + long long free = 0; + int i; + + for (i = 0; i < c->lpt_lebs; i++) { + if (i + c->lpt_first == c->nhead_lnum) + free += c->leb_size - c->nhead_offs; + else if (c->ltab[i].free == c->leb_size) + free += c->leb_size; + else if (c->ltab[i].free + c->ltab[i].dirty == c->leb_size) + free += c->leb_size; + } + /* Less than twice the size left */ + if (free <= c->lpt_sz * 2) + return 1; + return 0; +} + +/** + * lpt_tgc_start - start trivial garbage collection of LPT LEBs. + * @c: UBIFS file-system description object + * + * LPT trivial garbage collection is where a LPT LEB contains only dirty and + * free space and so may be reused as soon as the next commit is completed. + * This function is called during start commit to mark LPT LEBs for trivial GC. + */ +static void lpt_tgc_start(struct ubifs_info *c) +{ + int i; + + for (i = 0; i < c->lpt_lebs; i++) { + if (i + c->lpt_first == c->nhead_lnum) + continue; + if (c->ltab[i].dirty > 0 && + c->ltab[i].free + c->ltab[i].dirty == c->leb_size) { + c->ltab[i].tgc = 1; + c->ltab[i].free = c->leb_size; + c->ltab[i].dirty = 0; + dbg_lp("LEB %d", i + c->lpt_first); + } + } +} + +/** + * lpt_tgc_end - end trivial garbage collection of LPT LEBs. + * @c: UBIFS file-system description object + * + * LPT trivial garbage collection is where a LPT LEB contains only dirty and + * free space and so may be reused as soon as the next commit is completed. + * This function is called after the commit is completed (master node has been + * written) and un-maps LPT LEBs that were marked for trivial GC. + */ +static int lpt_tgc_end(struct ubifs_info *c) +{ + int i, err; + + for (i = 0; i < c->lpt_lebs; i++) + if (c->ltab[i].tgc) { + err = ubifs_leb_unmap(c, i + c->lpt_first); + if (err) + return err; + c->ltab[i].tgc = 0; + dbg_lp("LEB %d", i + c->lpt_first); + } + return 0; +} + +/** + * populate_lsave - fill the lsave array with important LEB numbers. + * @c: the UBIFS file-system description object + * + * This function is only called for the "big" model. It records a small number + * of LEB numbers of important LEBs. Important LEBs are ones that are (from + * most important to least important): empty, freeable, freeable index, dirty + * index, dirty or free. Upon mount, we read this list of LEB numbers and bring + * their pnodes into memory. That will stop us from having to scan the LPT + * straight away. For the "small" model we assume that scanning the LPT is no + * big deal. + */ +static void populate_lsave(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + struct ubifs_lpt_heap *heap; + int i, cnt = 0; + + ubifs_assert(c, c->big_lpt); + if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) { + c->lpt_drty_flgs |= LSAVE_DIRTY; + ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz); + } + + if (dbg_populate_lsave(c)) + return; + + list_for_each_entry(lprops, &c->empty_list, list) { + c->lsave[cnt++] = lprops->lnum; + if (cnt >= c->lsave_cnt) + return; + } + list_for_each_entry(lprops, &c->freeable_list, list) { + c->lsave[cnt++] = lprops->lnum; + if (cnt >= c->lsave_cnt) + return; + } + list_for_each_entry(lprops, &c->frdi_idx_list, list) { + c->lsave[cnt++] = lprops->lnum; + if (cnt >= c->lsave_cnt) + return; + } + heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1]; + for (i = 0; i < heap->cnt; i++) { + c->lsave[cnt++] = heap->arr[i]->lnum; + if (cnt >= c->lsave_cnt) + return; + } + heap = &c->lpt_heap[LPROPS_DIRTY - 1]; + for (i = 0; i < heap->cnt; i++) { + c->lsave[cnt++] = heap->arr[i]->lnum; + if (cnt >= c->lsave_cnt) + return; + } + heap = &c->lpt_heap[LPROPS_FREE - 1]; + for (i = 0; i < heap->cnt; i++) { + c->lsave[cnt++] = heap->arr[i]->lnum; + if (cnt >= c->lsave_cnt) + return; + } + /* Fill it up completely */ + while (cnt < c->lsave_cnt) + c->lsave[cnt++] = c->main_first; +} + +/** + * nnode_lookup - lookup a nnode in the LPT. + * @c: UBIFS file-system description object + * @i: nnode number + * + * This function returns a pointer to the nnode on success or a negative + * error code on failure. + */ +static struct ubifs_nnode *nnode_lookup(struct ubifs_info *c, int i) +{ + int err, iip; + struct ubifs_nnode *nnode; + + if (!c->nroot) { + err = ubifs_read_nnode(c, NULL, 0); + if (err) + return ERR_PTR(err); + } + nnode = c->nroot; + while (1) { + iip = i & (UBIFS_LPT_FANOUT - 1); + i >>= UBIFS_LPT_FANOUT_SHIFT; + if (!i) + break; + nnode = ubifs_get_nnode(c, nnode, iip); + if (IS_ERR(nnode)) + return nnode; + } + return nnode; +} + +/** + * make_nnode_dirty - find a nnode and, if found, make it dirty. + * @c: UBIFS file-system description object + * @node_num: nnode number of nnode to make dirty + * @lnum: LEB number where nnode was written + * @offs: offset where nnode was written + * + * This function is used by LPT garbage collection. LPT garbage collection is + * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection + * simply involves marking all the nodes in the LEB being garbage-collected as + * dirty. The dirty nodes are written next commit, after which the LEB is free + * to be reused. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int make_nnode_dirty(struct ubifs_info *c, int node_num, int lnum, + int offs) +{ + struct ubifs_nnode *nnode; + + nnode = nnode_lookup(c, node_num); + if (IS_ERR(nnode)) + return PTR_ERR(nnode); + if (nnode->parent) { + struct ubifs_nbranch *branch; + + branch = &nnode->parent->nbranch[nnode->iip]; + if (branch->lnum != lnum || branch->offs != offs) + return 0; /* nnode is obsolete */ + } else if (c->lpt_lnum != lnum || c->lpt_offs != offs) + return 0; /* nnode is obsolete */ + /* Assumes cnext list is empty i.e. not called during commit */ + ubifs_make_nnode_dirty(c, nnode); + return 0; +} + +/** + * make_pnode_dirty - find a pnode and, if found, make it dirty. + * @c: UBIFS file-system description object + * @node_num: pnode number of pnode to make dirty + * @lnum: LEB number where pnode was written + * @offs: offset where pnode was written + * + * This function is used by LPT garbage collection. LPT garbage collection is + * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection + * simply involves marking all the nodes in the LEB being garbage-collected as + * dirty. The dirty nodes are written next commit, after which the LEB is free + * to be reused. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int make_pnode_dirty(struct ubifs_info *c, int node_num, int lnum, + int offs) +{ + struct ubifs_pnode *pnode; + struct ubifs_nbranch *branch; + + pnode = ubifs_pnode_lookup(c, node_num); + if (IS_ERR(pnode)) + return PTR_ERR(pnode); + branch = &pnode->parent->nbranch[pnode->iip]; + if (branch->lnum != lnum || branch->offs != offs) + return 0; + ubifs_make_pnode_dirty(c, pnode); + return 0; +} + +/** + * make_ltab_dirty - make ltab node dirty. + * @c: UBIFS file-system description object + * @lnum: LEB number where ltab was written + * @offs: offset where ltab was written + * + * This function is used by LPT garbage collection. LPT garbage collection is + * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection + * simply involves marking all the nodes in the LEB being garbage-collected as + * dirty. The dirty nodes are written next commit, after which the LEB is free + * to be reused. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int make_ltab_dirty(struct ubifs_info *c, int lnum, int offs) +{ + if (lnum != c->ltab_lnum || offs != c->ltab_offs) + return 0; /* This ltab node is obsolete */ + if (!(c->lpt_drty_flgs & LTAB_DIRTY)) { + c->lpt_drty_flgs |= LTAB_DIRTY; + ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz); + } + return 0; +} + +/** + * make_lsave_dirty - make lsave node dirty. + * @c: UBIFS file-system description object + * @lnum: LEB number where lsave was written + * @offs: offset where lsave was written + * + * This function is used by LPT garbage collection. LPT garbage collection is + * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection + * simply involves marking all the nodes in the LEB being garbage-collected as + * dirty. The dirty nodes are written next commit, after which the LEB is free + * to be reused. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int make_lsave_dirty(struct ubifs_info *c, int lnum, int offs) +{ + if (lnum != c->lsave_lnum || offs != c->lsave_offs) + return 0; /* This lsave node is obsolete */ + if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) { + c->lpt_drty_flgs |= LSAVE_DIRTY; + ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz); + } + return 0; +} + +/** + * make_node_dirty - make node dirty. + * @c: UBIFS file-system description object + * @node_type: LPT node type + * @node_num: node number + * @lnum: LEB number where node was written + * @offs: offset where node was written + * + * This function is used by LPT garbage collection. LPT garbage collection is + * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection + * simply involves marking all the nodes in the LEB being garbage-collected as + * dirty. The dirty nodes are written next commit, after which the LEB is free + * to be reused. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num, + int lnum, int offs) +{ + switch (node_type) { + case UBIFS_LPT_NNODE: + return make_nnode_dirty(c, node_num, lnum, offs); + case UBIFS_LPT_PNODE: + return make_pnode_dirty(c, node_num, lnum, offs); + case UBIFS_LPT_LTAB: + return make_ltab_dirty(c, lnum, offs); + case UBIFS_LPT_LSAVE: + return make_lsave_dirty(c, lnum, offs); + } + return -EINVAL; +} + +/** + * get_lpt_node_len - return the length of a node based on its type. + * @c: UBIFS file-system description object + * @node_type: LPT node type + */ +static int get_lpt_node_len(const struct ubifs_info *c, int node_type) +{ + switch (node_type) { + case UBIFS_LPT_NNODE: + return c->nnode_sz; + case UBIFS_LPT_PNODE: + return c->pnode_sz; + case UBIFS_LPT_LTAB: + return c->ltab_sz; + case UBIFS_LPT_LSAVE: + return c->lsave_sz; + } + return 0; +} + +/** + * get_pad_len - return the length of padding in a buffer. + * @c: UBIFS file-system description object + * @buf: buffer + * @len: length of buffer + */ +static int get_pad_len(const struct ubifs_info *c, __unused uint8_t *buf, + int len) +{ + int offs, pad_len; + + if (c->min_io_size == 1) + return 0; + offs = c->leb_size - len; + pad_len = ALIGN(offs, c->min_io_size) - offs; + return pad_len; +} + +/** + * get_lpt_node_type - return type (and node number) of a node in a buffer. + * @c: UBIFS file-system description object + * @buf: buffer + * @node_num: node number is returned here + */ +static int get_lpt_node_type(const struct ubifs_info *c, uint8_t *buf, + int *node_num) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int pos = 0, node_type; + + node_type = ubifs_unpack_bits(c, &addr, &pos, UBIFS_LPT_TYPE_BITS); + *node_num = ubifs_unpack_bits(c, &addr, &pos, c->pcnt_bits); + return node_type; +} + +/** + * is_a_node - determine if a buffer contains a node. + * @c: UBIFS file-system description object + * @buf: buffer + * @len: length of buffer + * + * This function returns %1 if the buffer contains a node or %0 if it does not. + */ +static int is_a_node(const struct ubifs_info *c, uint8_t *buf, int len) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int pos = 0, node_type, node_len; + uint16_t crc, calc_crc; + + if (len < UBIFS_LPT_CRC_BYTES + (UBIFS_LPT_TYPE_BITS + 7) / 8) + return 0; + node_type = ubifs_unpack_bits(c, &addr, &pos, UBIFS_LPT_TYPE_BITS); + if (node_type == UBIFS_LPT_NOT_A_NODE) + return 0; + node_len = get_lpt_node_len(c, node_type); + if (!node_len || node_len > len) + return 0; + pos = 0; + addr = buf; + crc = ubifs_unpack_bits(c, &addr, &pos, UBIFS_LPT_CRC_BITS); + calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + node_len - UBIFS_LPT_CRC_BYTES); + if (crc != calc_crc) + return 0; + return 1; +} + +/** + * lpt_gc_lnum - garbage collect a LPT LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number to garbage collect + * + * LPT garbage collection is used only for the "big" LPT model + * (c->big_lpt == 1). Garbage collection simply involves marking all the nodes + * in the LEB being garbage-collected as dirty. The dirty nodes are written + * next commit, after which the LEB is free to be reused. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int lpt_gc_lnum(struct ubifs_info *c, int lnum) +{ + int err, len = c->leb_size, node_type, node_num, node_len, offs; + void *buf = c->lpt_buf; + + dbg_lp("LEB %d", lnum); + + err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1); + if (err) + return err; + + while (1) { + if (!is_a_node(c, buf, len)) { + int pad_len; + + pad_len = get_pad_len(c, buf, len); + if (pad_len) { + buf += pad_len; + len -= pad_len; + continue; + } + return 0; + } + node_type = get_lpt_node_type(c, buf, &node_num); + node_len = get_lpt_node_len(c, node_type); + offs = c->leb_size - len; + ubifs_assert(c, node_len != 0); + mutex_lock(&c->lp_mutex); + err = make_node_dirty(c, node_type, node_num, lnum, offs); + mutex_unlock(&c->lp_mutex); + if (err) + return err; + buf += node_len; + len -= node_len; + } + return 0; +} + +/** + * lpt_gc - LPT garbage collection. + * @c: UBIFS file-system description object + * + * Select a LPT LEB for LPT garbage collection and call 'lpt_gc_lnum()'. + * Returns %0 on success and a negative error code on failure. + */ +static int lpt_gc(struct ubifs_info *c) +{ + int i, lnum = -1, dirty = 0; + + mutex_lock(&c->lp_mutex); + for (i = 0; i < c->lpt_lebs; i++) { + ubifs_assert(c, !c->ltab[i].tgc); + if (i + c->lpt_first == c->nhead_lnum || + c->ltab[i].free + c->ltab[i].dirty == c->leb_size) + continue; + if (c->ltab[i].dirty > dirty) { + dirty = c->ltab[i].dirty; + lnum = i + c->lpt_first; + } + } + mutex_unlock(&c->lp_mutex); + if (lnum == -1) + return -ENOSPC; + return lpt_gc_lnum(c, lnum); +} + +/** + * ubifs_lpt_start_commit - UBIFS commit starts. + * @c: the UBIFS file-system description object + * + * This function has to be called when UBIFS starts the commit operation. + * This function "freezes" all currently dirty LEB properties and does not + * change them anymore. Further changes are saved and tracked separately + * because they are not part of this commit. This function returns zero in case + * of success and a negative error code in case of failure. + */ +int ubifs_lpt_start_commit(struct ubifs_info *c) +{ + int err, cnt; + + dbg_lp(""); + + mutex_lock(&c->lp_mutex); + err = dbg_chk_lpt_free_spc(c); + if (err) + goto out; + err = dbg_check_ltab(c); + if (err) + goto out; + + if (c->check_lpt_free) { + /* + * We ensure there is enough free space in + * ubifs_lpt_post_commit() by marking nodes dirty. That + * information is lost when we unmount, so we also need + * to check free space once after mounting also. + */ + c->check_lpt_free = 0; + while (need_write_all(c)) { + mutex_unlock(&c->lp_mutex); + err = lpt_gc(c); + if (err) + return err; + mutex_lock(&c->lp_mutex); + } + } + + lpt_tgc_start(c); + + if (!c->dirty_pn_cnt) { + dbg_cmt("no cnodes to commit"); + err = 0; + goto out; + } + + if (!c->big_lpt && need_write_all(c)) { + /* If needed, write everything */ + err = make_tree_dirty(c); + if (err) + goto out; + lpt_tgc_start(c); + } + + if (c->big_lpt) + populate_lsave(c); + + cnt = get_cnodes_to_commit(c); + ubifs_assert(c, cnt != 0); + + err = layout_cnodes(c); + if (err) + goto out; + + err = ubifs_lpt_calc_hash(c, c->mst_node->hash_lpt); + if (err) + goto out; + + /* Copy the LPT's own lprops for end commit to write */ + memcpy(c->ltab_cmt, c->ltab, + sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs); + c->lpt_drty_flgs &= ~(LTAB_DIRTY | LSAVE_DIRTY); + +out: + mutex_unlock(&c->lp_mutex); + return err; +} + +/** + * free_obsolete_cnodes - free obsolete cnodes for commit end. + * @c: UBIFS file-system description object + */ +static void free_obsolete_cnodes(struct ubifs_info *c) +{ + struct ubifs_cnode *cnode, *cnext; + + cnext = c->lpt_cnext; + if (!cnext) + return; + do { + cnode = cnext; + cnext = cnode->cnext; + if (test_bit(OBSOLETE_CNODE, &cnode->flags)) + kfree(cnode); + else + cnode->cnext = NULL; + } while (cnext != c->lpt_cnext); + c->lpt_cnext = NULL; +} + +/** + * ubifs_lpt_end_commit - finish the commit operation. + * @c: the UBIFS file-system description object + * + * This function has to be called when the commit operation finishes. It + * flushes the changes which were "frozen" by 'ubifs_lprops_start_commit()' to + * the media. Returns zero in case of success and a negative error code in case + * of failure. + */ +int ubifs_lpt_end_commit(struct ubifs_info *c) +{ + int err; + + dbg_lp(""); + + if (!c->lpt_cnext) + return 0; + + err = write_cnodes(c); + if (err) + return err; + + mutex_lock(&c->lp_mutex); + free_obsolete_cnodes(c); + mutex_unlock(&c->lp_mutex); + + return 0; +} + +/** + * ubifs_lpt_post_commit - post commit LPT trivial GC and LPT GC. + * @c: UBIFS file-system description object + * + * LPT trivial GC is completed after a commit. Also LPT GC is done after a + * commit for the "big" LPT model. + */ +int ubifs_lpt_post_commit(struct ubifs_info *c) +{ + int err; + + mutex_lock(&c->lp_mutex); + err = lpt_tgc_end(c); + if (err) + goto out; + if (c->big_lpt) + while (need_write_all(c)) { + mutex_unlock(&c->lp_mutex); + err = lpt_gc(c); + if (err) + return err; + mutex_lock(&c->lp_mutex); + } +out: + mutex_unlock(&c->lp_mutex); + return err; +} + +/** + * first_nnode - find the first nnode in memory. + * @c: UBIFS file-system description object + * @hght: height of tree where nnode found is returned here + * + * This function returns a pointer to the nnode found or %NULL if no nnode is + * found. This function is a helper to 'ubifs_lpt_free()'. + */ +static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght) +{ + struct ubifs_nnode *nnode; + int h, i, found; + + nnode = c->nroot; + *hght = 0; + if (!nnode) + return NULL; + for (h = 1; h < c->lpt_hght; h++) { + found = 0; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (nnode->nbranch[i].nnode) { + found = 1; + nnode = nnode->nbranch[i].nnode; + *hght = h; + break; + } + } + if (!found) + break; + } + return nnode; +} + +/** + * next_nnode - find the next nnode in memory. + * @c: UBIFS file-system description object + * @nnode: nnode from which to start. + * @hght: height of tree where nnode is, is passed and returned here + * + * This function returns a pointer to the nnode found or %NULL if no nnode is + * found. This function is a helper to 'ubifs_lpt_free()'. + */ +static struct ubifs_nnode *next_nnode(struct ubifs_info *c, + struct ubifs_nnode *nnode, int *hght) +{ + struct ubifs_nnode *parent; + int iip, h, i, found; + + parent = nnode->parent; + if (!parent) + return NULL; + if (nnode->iip == UBIFS_LPT_FANOUT - 1) { + *hght -= 1; + return parent; + } + for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) { + nnode = parent->nbranch[iip].nnode; + if (nnode) + break; + } + if (!nnode) { + *hght -= 1; + return parent; + } + for (h = *hght + 1; h < c->lpt_hght; h++) { + found = 0; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (nnode->nbranch[i].nnode) { + found = 1; + nnode = nnode->nbranch[i].nnode; + *hght = h; + break; + } + } + if (!found) + break; + } + return nnode; +} + +/** + * ubifs_free_lpt_nodes - free pnodes/nnodes in LPT. + * @c: UBIFS file-system description object + */ +void ubifs_free_lpt_nodes(struct ubifs_info *c) +{ + int i, hght; + struct ubifs_nnode *nnode; + + nnode = first_nnode(c, &hght); + while (nnode) { + for (i = 0; i < UBIFS_LPT_FANOUT; i++) + kfree(nnode->nbranch[i].nnode); + nnode = next_nnode(c, nnode, &hght); + } + + kfree(c->nroot); + c->nroot = NULL; +} + +/** + * ubifs_lpt_free - free resources owned by the LPT. + * @c: UBIFS file-system description object + * @wr_only: free only resources used for writing + */ +void ubifs_lpt_free(struct ubifs_info *c, int wr_only) +{ + int i; + + /* Free write-only things first */ + + free_obsolete_cnodes(c); /* Leftover from a failed commit */ + + vfree(c->ltab_cmt); + c->ltab_cmt = NULL; + vfree(c->lpt_buf); + c->lpt_buf = NULL; + kfree(c->lsave); + c->lsave = NULL; + + if (wr_only) + return; + + /* Now free the rest */ + + ubifs_free_lpt_nodes(c); + for (i = 0; i < LPROPS_HEAP_CNT; i++) + kfree(c->lpt_heap[i].arr); + kfree(c->dirty_idx.arr); + vfree(c->ltab); + c->ltab = NULL; + kfree(c->lpt_nod_buf); +} + +/* + * Everything below is related to debugging. + */ + +/** + * dbg_is_all_ff - determine if a buffer contains only 0xFF bytes. + * @buf: buffer + * @len: buffer length + */ +static int dbg_is_all_ff(uint8_t *buf, int len) +{ + int i; + + for (i = 0; i < len; i++) + if (buf[i] != 0xff) + return 0; + return 1; +} + +/** + * dbg_is_nnode_dirty - determine if a nnode is dirty. + * @c: the UBIFS file-system description object + * @lnum: LEB number where nnode was written + * @offs: offset where nnode was written + */ +static int dbg_is_nnode_dirty(struct ubifs_info *c, int lnum, int offs) +{ + struct ubifs_nnode *nnode; + int hght; + + /* Entire tree is in memory so first_nnode / next_nnode are OK */ + nnode = first_nnode(c, &hght); + for (; nnode; nnode = next_nnode(c, nnode, &hght)) { + struct ubifs_nbranch *branch; + + cond_resched(); + if (nnode->parent) { + branch = &nnode->parent->nbranch[nnode->iip]; + if (branch->lnum != lnum || branch->offs != offs) + continue; + if (test_bit(DIRTY_CNODE, &nnode->flags)) + return 1; + return 0; + } else { + if (c->lpt_lnum != lnum || c->lpt_offs != offs) + continue; + if (test_bit(DIRTY_CNODE, &nnode->flags)) + return 1; + return 0; + } + } + return 1; +} + +/** + * dbg_is_pnode_dirty - determine if a pnode is dirty. + * @c: the UBIFS file-system description object + * @lnum: LEB number where pnode was written + * @offs: offset where pnode was written + */ +static int dbg_is_pnode_dirty(struct ubifs_info *c, int lnum, int offs) +{ + int i, cnt; + + cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); + for (i = 0; i < cnt; i++) { + struct ubifs_pnode *pnode; + struct ubifs_nbranch *branch; + + cond_resched(); + pnode = ubifs_pnode_lookup(c, i); + if (IS_ERR(pnode)) + return PTR_ERR(pnode); + branch = &pnode->parent->nbranch[pnode->iip]; + if (branch->lnum != lnum || branch->offs != offs) + continue; + if (test_bit(DIRTY_CNODE, &pnode->flags)) + return 1; + return 0; + } + return 1; +} + +/** + * dbg_is_ltab_dirty - determine if a ltab node is dirty. + * @c: the UBIFS file-system description object + * @lnum: LEB number where ltab node was written + * @offs: offset where ltab node was written + */ +static int dbg_is_ltab_dirty(struct ubifs_info *c, int lnum, int offs) +{ + if (lnum != c->ltab_lnum || offs != c->ltab_offs) + return 1; + return (c->lpt_drty_flgs & LTAB_DIRTY) != 0; +} + +/** + * dbg_is_lsave_dirty - determine if a lsave node is dirty. + * @c: the UBIFS file-system description object + * @lnum: LEB number where lsave node was written + * @offs: offset where lsave node was written + */ +static int dbg_is_lsave_dirty(struct ubifs_info *c, int lnum, int offs) +{ + if (lnum != c->lsave_lnum || offs != c->lsave_offs) + return 1; + return (c->lpt_drty_flgs & LSAVE_DIRTY) != 0; +} + +/** + * dbg_is_node_dirty - determine if a node is dirty. + * @c: the UBIFS file-system description object + * @node_type: node type + * @lnum: LEB number where node was written + * @offs: offset where node was written + */ +static int dbg_is_node_dirty(struct ubifs_info *c, int node_type, int lnum, + int offs) +{ + switch (node_type) { + case UBIFS_LPT_NNODE: + return dbg_is_nnode_dirty(c, lnum, offs); + case UBIFS_LPT_PNODE: + return dbg_is_pnode_dirty(c, lnum, offs); + case UBIFS_LPT_LTAB: + return dbg_is_ltab_dirty(c, lnum, offs); + case UBIFS_LPT_LSAVE: + return dbg_is_lsave_dirty(c, lnum, offs); + } + return 1; +} + +/** + * dbg_check_ltab_lnum - check the ltab for a LPT LEB number. + * @c: the UBIFS file-system description object + * @lnum: LEB number where node was written + * + * This function returns %0 on success and a negative error code on failure. + */ +int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum) +{ + int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len; + int ret; + void *buf, *p; + + buf = p = __vmalloc(c->leb_size, GFP_NOFS); + if (!buf) { + ubifs_err(c, "cannot allocate memory for ltab checking"); + return -ENOMEM; + } + + dbg_lp("LEB %d", lnum); + + err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1); + if (err) { + if (err == -EBADMSG) + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + goto out; + } + + while (1) { + if (!is_a_node(c, p, len)) { + int i, pad_len; + + pad_len = get_pad_len(c, p, len); + if (pad_len) { + p += pad_len; + len -= pad_len; + dirty += pad_len; + continue; + } + if (!dbg_is_all_ff(p, len)) { + set_failure_reason_callback(c, FR_LPT_CORRUPTED); + ubifs_err(c, "invalid empty space in LEB %d at %d", + lnum, c->leb_size - len); + err = -EINVAL; + goto out; + } + i = lnum - c->lpt_first; + if (len != c->ltab[i].free) { + ubifs_err(c, "invalid free space in LEB %d (free %d, expected %d)", + lnum, c->ltab[i].free, len); + err = -EINVAL; + if (handle_failure_callback(c, FR_H_LTAB_INCORRECT, NULL)) { + c->ltab[i].free = len; + err = 0; + } + } + if (dirty != c->ltab[i].dirty) { + ubifs_err(c, "invalid dirty space in LEB %d (dirty %d, expected %d)", + lnum, c->ltab[i].dirty, dirty); + err = -EINVAL; + if (handle_failure_callback(c, FR_H_LTAB_INCORRECT, NULL)) { + c->ltab[i].dirty = dirty; + err = 0; + } + } + goto out; + } + node_type = get_lpt_node_type(c, p, &node_num); + node_len = get_lpt_node_len(c, node_type); + ret = dbg_is_node_dirty(c, node_type, lnum, c->leb_size - len); + if (ret == 1) + dirty += node_len; + p += node_len; + len -= node_len; + } + +out: + vfree(buf); + return err; +} + +/** + * dump_lpt_leb - dump an LPT LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number to dump + * + * This function dumps an LEB from LPT area. Nodes in this area are very + * different to nodes in the main area (e.g., they do not have common headers, + * they do not have 8-byte alignments, etc), so we have a separate function to + * dump LPT area LEBs. Note, LPT has to be locked by the caller. + */ +static void dump_lpt_leb(const struct ubifs_info *c, int lnum) +{ + int err, len = c->leb_size, node_type, node_num, node_len, offs; + void *buf, *p; + + pr_err("(pid %d) start dumping LEB %d\n", getpid(), lnum); + buf = p = __vmalloc(c->leb_size, GFP_NOFS); + if (!buf) { + ubifs_err(c, "cannot allocate memory to dump LPT"); + return; + } + + err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1); + if (err) + goto out; + + while (1) { + offs = c->leb_size - len; + if (!is_a_node(c, p, len)) { + int pad_len; + + pad_len = get_pad_len(c, p, len); + if (pad_len) { + pr_err("LEB %d:%d, pad %d bytes\n", + lnum, offs, pad_len); + p += pad_len; + len -= pad_len; + continue; + } + if (len) + pr_err("LEB %d:%d, free %d bytes\n", + lnum, offs, len); + break; + } + + node_type = get_lpt_node_type(c, p, &node_num); + switch (node_type) { + case UBIFS_LPT_PNODE: + { + node_len = c->pnode_sz; + if (c->big_lpt) + pr_err("LEB %d:%d, pnode num %d\n", + lnum, offs, node_num); + else + pr_err("LEB %d:%d, pnode\n", lnum, offs); + break; + } + case UBIFS_LPT_NNODE: + { + int i; + struct ubifs_nnode nnode; + + node_len = c->nnode_sz; + if (c->big_lpt) + pr_err("LEB %d:%d, nnode num %d, ", + lnum, offs, node_num); + else + pr_err("LEB %d:%d, nnode, ", + lnum, offs); + err = ubifs_unpack_nnode(c, p, &nnode); + if (err) { + pr_err("failed to unpack_node, error %d\n", + err); + break; + } + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + pr_cont("%d:%d", nnode.nbranch[i].lnum, + nnode.nbranch[i].offs); + if (i != UBIFS_LPT_FANOUT - 1) + pr_cont(", "); + } + pr_cont("\n"); + break; + } + case UBIFS_LPT_LTAB: + node_len = c->ltab_sz; + pr_err("LEB %d:%d, ltab\n", lnum, offs); + break; + case UBIFS_LPT_LSAVE: + node_len = c->lsave_sz; + pr_err("LEB %d:%d, lsave len\n", lnum, offs); + break; + default: + ubifs_err(c, "LPT node type %d not recognized", node_type); + goto out; + } + + p += node_len; + len -= node_len; + } + + pr_err("(pid %d) finish dumping LEB %d\n", getpid(), lnum); +out: + vfree(buf); + return; +} + +/** + * ubifs_dump_lpt_lebs - dump LPT lebs. + * @c: UBIFS file-system description object + * + * This function dumps all LPT LEBs. The caller has to make sure the LPT is + * locked. + */ +void ubifs_dump_lpt_lebs(const struct ubifs_info *c) +{ + int i; + + pr_err("(pid %d) start dumping all LPT LEBs\n", getpid()); + for (i = 0; i < c->lpt_lebs; i++) + dump_lpt_leb(c, i + c->lpt_first); + pr_err("(pid %d) finish dumping all LPT LEBs\n", getpid()); +} + +/** + * dbg_populate_lsave - debugging version of 'populate_lsave()' + * @c: UBIFS file-system description object + * + * This is a debugging version for 'populate_lsave()' which populates lsave + * with random LEBs instead of useful LEBs, which is good for test coverage. + * Returns zero if lsave has not been populated (this debugging feature is + * disabled) an non-zero if lsave has been populated. + */ +static int dbg_populate_lsave(__unused struct ubifs_info *c) +{ + return 0; +} diff --git a/ubifs-utils/libubifs/master.c b/ubifs-utils/libubifs/master.c new file mode 100644 index 0000000..54d2a78 --- /dev/null +++ b/ubifs-utils/libubifs/master.c @@ -0,0 +1,489 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* This file implements reading and writing the master node */ + +#include "linux_err.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" + +/** + * ubifs_compare_master_node - compare two UBIFS master nodes + * @c: UBIFS file-system description object + * @m1: the first node + * @m2: the second node + * + * This function compares two UBIFS master nodes. Returns 0 if they are equal + * and nonzero if not. + */ +int ubifs_compare_master_node(__unused struct ubifs_info *c, void *m1, void *m2) +{ + int ret; + int behind; + int hmac_offs = offsetof(struct ubifs_mst_node, hmac); + + /* + * Do not compare the common node header since the sequence number and + * hence the CRC are different. + */ + ret = memcmp(m1 + UBIFS_CH_SZ, m2 + UBIFS_CH_SZ, + hmac_offs - UBIFS_CH_SZ); + if (ret) + return ret; + + /* + * Do not compare the embedded HMAC as well which also must be different + * due to the different common node header. + */ + behind = hmac_offs + UBIFS_MAX_HMAC_LEN; + + if (UBIFS_MST_NODE_SZ > behind) + return memcmp(m1 + behind, m2 + behind, UBIFS_MST_NODE_SZ - behind); + + return 0; +} + +/* mst_node_check_hash - Check hash of a master node + * @c: UBIFS file-system description object + * @mst: The master node + * @expected: The expected hash of the master node + * + * This checks the hash of a master node against a given expected hash. + * Note that we have two master nodes on a UBIFS image which have different + * sequence numbers and consequently different CRCs. To be able to match + * both master nodes we exclude the common node header containing the sequence + * number and CRC from the hash. + * + * Returns 0 if the hashes are equal, a negative error code otherwise. + */ +static int mst_node_check_hash(__unused const struct ubifs_info *c, + __unused const struct ubifs_mst_node *mst, + __unused const u8 *expected) +{ + // To be implemented + return 0; +} + +/** + * scan_for_master - search the valid master node. + * @c: UBIFS file-system description object + * + * This function scans the master node LEBs and search for the latest master + * node. Returns zero in case of success, %-EUCLEAN if there master area is + * corrupted and requires recovery, and a negative error code in case of + * failure. + */ +static int scan_for_master(struct ubifs_info *c) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + int lnum, offs = 0, nodes_cnt, err; + + lnum = UBIFS_MST_LNUM; + + sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + nodes_cnt = sleb->nodes_cnt; + if (nodes_cnt > 0) { + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, + list); + if (snod->type != UBIFS_MST_NODE) + goto out_dump; + memcpy(c->mst_node, snod->node, snod->len); + offs = snod->offs; + } + ubifs_scan_destroy(sleb); + + lnum += 1; + + sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + if (sleb->nodes_cnt != nodes_cnt) + goto out; + if (!sleb->nodes_cnt) + goto out; + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list); + if (snod->type != UBIFS_MST_NODE) + goto out_dump; + if (snod->offs != offs) + goto out; + if (ubifs_compare_master_node(c, c->mst_node, snod->node)) + goto out; + + c->mst_offs = offs; + ubifs_scan_destroy(sleb); + + if (!ubifs_authenticated(c)) + return 0; + + if (ubifs_hmac_zero(c, c->mst_node->hmac)) { + err = mst_node_check_hash(c, c->mst_node, + c->sup_node->hash_mst); + if (err) + ubifs_err(c, "Failed to verify master node hash"); + } else { + err = ubifs_node_verify_hmac(c, c->mst_node, + sizeof(struct ubifs_mst_node), + offsetof(struct ubifs_mst_node, hmac)); + if (err) + ubifs_err(c, "Failed to verify master node HMAC"); + } + + if (err) + return -EPERM; + + return 0; + +out: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_scan_destroy(sleb); + return -EUCLEAN; + +out_dump: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "unexpected node type %d master LEB %d:%d", + snod->type, lnum, snod->offs); + ubifs_scan_destroy(sleb); + return -EINVAL; +} + +/** + * validate_master - validate master node. + * @c: UBIFS file-system description object + * + * This function validates data which was read from master node. Returns zero + * if the data is all right and %-EINVAL if not. + */ +static int validate_master(const struct ubifs_info *c) +{ + unsigned int reason = FR_DATA_CORRUPTED; + long long main_sz; + int err; + + if (c->max_sqnum >= SQNUM_WATERMARK) { + err = 1; + goto out; + } + + if (c->cmt_no >= c->max_sqnum) { + err = 2; + goto out; + } + + if (c->highest_inum >= INUM_WATERMARK) { + err = 3; + goto out; + } + + if (c->lhead_lnum < UBIFS_LOG_LNUM || + c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs || + c->lhead_offs < 0 || c->lhead_offs >= c->leb_size || + c->lhead_offs & (c->min_io_size - 1)) { + err = 4; + goto out; + } + + if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first || + c->zroot.offs >= c->leb_size || c->zroot.offs & 7) { + err = 5; + goto out; + } + + if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len || + c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) { + err = 6; + goto out; + } + + if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) { + err = 7; + goto out; + } + + if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first || + c->ihead_offs % c->min_io_size || c->ihead_offs < 0 || + c->ihead_offs > c->leb_size || c->ihead_offs & 7) { + err = 8; + goto out; + } + + main_sz = (long long)c->main_lebs * c->leb_size; + if (c->bi.old_idx_sz & 7 || c->bi.old_idx_sz >= main_sz) { + err = 9; + goto out; + } + + if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last || + c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) { + err = 10; + goto out; + } + + if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last || + c->nhead_offs < 0 || c->nhead_offs % c->min_io_size || + c->nhead_offs > c->leb_size) { + err = 11; + goto out; + } + + if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last || + c->ltab_offs < 0 || + c->ltab_offs + c->ltab_sz > c->leb_size) { + err = 12; + goto out; + } + + if (c->big_lpt && (c->lsave_lnum < c->lpt_first || + c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 || + c->lsave_offs + c->lsave_sz > c->leb_size)) { + err = 13; + goto out; + } + + if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) { + err = 14; + goto out; + } + + if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) { + reason = FR_LPT_INCORRECT; + err = 15; + goto out; + } + + if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) { + reason = FR_LPT_INCORRECT; + err = 16; + goto out; + } + + if (c->lst.total_free < 0 || c->lst.total_free > main_sz || + c->lst.total_free & 7) { + reason = FR_LPT_INCORRECT; + err = 17; + goto out; + } + + if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) { + reason = FR_LPT_INCORRECT; + err = 18; + goto out; + } + + if (c->lst.total_used < 0 || (c->lst.total_used & 7)) { + reason = FR_LPT_INCORRECT; + err = 19; + goto out; + } + + if (c->lst.total_free + c->lst.total_dirty + + c->lst.total_used > main_sz) { + reason = FR_LPT_INCORRECT; + err = 20; + goto out; + } + + if (c->lst.total_dead + c->lst.total_dark + + c->lst.total_used + c->bi.old_idx_sz > main_sz) { + reason = FR_LPT_INCORRECT; + err = 21; + goto out; + } + + if (c->lst.total_dead < 0 || + c->lst.total_dead > c->lst.total_free + c->lst.total_dirty || + c->lst.total_dead & 7) { + reason = FR_LPT_INCORRECT; + err = 22; + goto out; + } + + if (c->lst.total_dark < 0 || + c->lst.total_dark > c->lst.total_free + c->lst.total_dirty || + c->lst.total_dark & 7) { + reason = FR_LPT_INCORRECT; + err = 23; + goto out; + } + + return 0; + +out: + set_failure_reason_callback(c, reason); + ubifs_err(c, "bad master node at offset %d error %d", c->mst_offs, err); + ubifs_dump_node(c, c->mst_node, c->mst_node_alsz); + err = -EINVAL; + if (can_ignore_failure_callback(c, reason)) { + clear_failure_reason_callback(c); + err = 0; + } + return err; +} + +/** + * ubifs_read_master - read master node. + * @c: UBIFS file-system description object + * + * This function finds and reads the master node during file-system mount. If + * the flash is empty, it creates default master node as well. Returns zero in + * case of success and a negative error code in case of failure. + */ +int ubifs_read_master(struct ubifs_info *c) +{ + int err, old_leb_cnt; + + c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL); + if (!c->mst_node) + return -ENOMEM; + + err = scan_for_master(c); + if (err) { + if (err == -EUCLEAN) { + clear_failure_reason_callback(c); + err = ubifs_recover_master_node(c); + } + if (err) + /* + * Note, we do not free 'c->mst_node' here because the + * unmount routine will take care of this. + */ + return err; + } + + /* Make sure that the recovery flag is clear */ + c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY); + + c->max_sqnum = le64_to_cpu(c->mst_node->ch.sqnum); + c->highest_inum = le64_to_cpu(c->mst_node->highest_inum); + c->cmt_no = le64_to_cpu(c->mst_node->cmt_no); + c->zroot.lnum = le32_to_cpu(c->mst_node->root_lnum); + c->zroot.offs = le32_to_cpu(c->mst_node->root_offs); + c->zroot.len = le32_to_cpu(c->mst_node->root_len); + c->lhead_lnum = le32_to_cpu(c->mst_node->log_lnum); + c->gc_lnum = le32_to_cpu(c->mst_node->gc_lnum); + c->ihead_lnum = le32_to_cpu(c->mst_node->ihead_lnum); + c->ihead_offs = le32_to_cpu(c->mst_node->ihead_offs); + c->bi.old_idx_sz = le64_to_cpu(c->mst_node->index_size); + c->lpt_lnum = le32_to_cpu(c->mst_node->lpt_lnum); + c->lpt_offs = le32_to_cpu(c->mst_node->lpt_offs); + c->nhead_lnum = le32_to_cpu(c->mst_node->nhead_lnum); + c->nhead_offs = le32_to_cpu(c->mst_node->nhead_offs); + c->ltab_lnum = le32_to_cpu(c->mst_node->ltab_lnum); + c->ltab_offs = le32_to_cpu(c->mst_node->ltab_offs); + c->lsave_lnum = le32_to_cpu(c->mst_node->lsave_lnum); + c->lsave_offs = le32_to_cpu(c->mst_node->lsave_offs); + c->lscan_lnum = le32_to_cpu(c->mst_node->lscan_lnum); + c->lst.empty_lebs = le32_to_cpu(c->mst_node->empty_lebs); + c->lst.idx_lebs = le32_to_cpu(c->mst_node->idx_lebs); + old_leb_cnt = le32_to_cpu(c->mst_node->leb_cnt); + c->lst.total_free = le64_to_cpu(c->mst_node->total_free); + c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty); + c->lst.total_used = le64_to_cpu(c->mst_node->total_used); + c->lst.total_dead = le64_to_cpu(c->mst_node->total_dead); + c->lst.total_dark = le64_to_cpu(c->mst_node->total_dark); + + ubifs_copy_hash(c, c->mst_node->hash_root_idx, c->zroot.hash); + + c->calc_idx_sz = c->bi.old_idx_sz; + + if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS)) + c->no_orphs = 1; + + if (old_leb_cnt != c->leb_cnt) { + /* The file system has been resized */ + int growth = c->leb_cnt - old_leb_cnt; + + if (c->leb_cnt < old_leb_cnt || + c->leb_cnt < UBIFS_MIN_LEB_CNT) { + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "bad leb_cnt on master node"); + ubifs_dump_node(c, c->mst_node, c->mst_node_alsz); + return -EINVAL; + } + + dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs", + old_leb_cnt, c->leb_cnt); + c->lst.empty_lebs += growth; + c->lst.total_free += growth * (long long)c->leb_size; + c->lst.total_dark += growth * (long long)c->dark_wm; + + /* + * Reflect changes back onto the master node. N.B. the master + * node gets written immediately whenever mounting (or + * remounting) in read-write mode, so we do not need to write it + * here. + */ + c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt); + c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs); + c->mst_node->total_free = cpu_to_le64(c->lst.total_free); + c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark); + } + + err = validate_master(c); + if (err) + return err; + + err = dbg_old_index_check_init(c, &c->zroot); + + return err; +} + +/** + * ubifs_write_master - write master node. + * @c: UBIFS file-system description object + * + * This function writes the master node. Returns zero in case of success and a + * negative error code in case of failure. The master node is written twice to + * enable recovery. + */ +int ubifs_write_master(struct ubifs_info *c) +{ + int err, lnum, offs, len; + + ubifs_assert(c, !c->ro_media && !c->ro_mount); + if (c->ro_error) + return -EROFS; + + lnum = UBIFS_MST_LNUM; + offs = c->mst_offs + c->mst_node_alsz; + len = UBIFS_MST_NODE_SZ; + + if (offs + UBIFS_MST_NODE_SZ > c->leb_size) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + offs = 0; + } + + c->mst_offs = offs; + c->mst_node->highest_inum = cpu_to_le64(c->highest_inum); + + ubifs_copy_hash(c, c->zroot.hash, c->mst_node->hash_root_idx); + err = ubifs_write_node_hmac(c, c->mst_node, len, lnum, offs, + offsetof(struct ubifs_mst_node, hmac)); + if (err) + return err; + + lnum += 1; + + if (offs == 0) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + err = ubifs_write_node_hmac(c, c->mst_node, len, lnum, offs, + offsetof(struct ubifs_mst_node, hmac)); + + return err; +} diff --git a/ubifs-utils/libubifs/misc.h b/ubifs-utils/libubifs/misc.h new file mode 100644 index 0000000..1b4404f --- /dev/null +++ b/ubifs-utils/libubifs/misc.h @@ -0,0 +1,225 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file contains miscellaneous helper functions. + */ + +#ifndef __UBIFS_MISC_H__ +#define __UBIFS_MISC_H__ + +/** + * ubifs_zn_dirty - check if znode is dirty. + * @znode: znode to check + * + * This helper function returns %1 if @znode is dirty and %0 otherwise. + */ +static inline int ubifs_zn_dirty(const struct ubifs_znode *znode) +{ + return !!test_bit(DIRTY_ZNODE, &znode->flags); +} + +/** + * ubifs_zn_obsolete - check if znode is obsolete. + * @znode: znode to check + * + * This helper function returns %1 if @znode is obsolete and %0 otherwise. + */ +static inline int ubifs_zn_obsolete(const struct ubifs_znode *znode) +{ + return !!test_bit(OBSOLETE_ZNODE, &znode->flags); +} + +/** + * ubifs_zn_cow - check if znode has to be copied on write. + * @znode: znode to check + * + * This helper function returns %1 if @znode is has COW flag set and %0 + * otherwise. + */ +static inline int ubifs_zn_cow(const struct ubifs_znode *znode) +{ + return !!test_bit(COW_ZNODE, &znode->flags); +} + +/** + * ubifs_tnc_find_child - find next child in znode. + * @znode: znode to search at + * @start: the zbranch index to start at + * + * This helper function looks for znode child starting at index @start. Returns + * the child or %NULL if no children were found. + */ +static inline struct ubifs_znode * +ubifs_tnc_find_child(struct ubifs_znode *znode, int start) +{ + while (start < znode->child_cnt) { + if (znode->zbranch[start].znode) + return znode->zbranch[start].znode; + start += 1; + } + + return NULL; +} + +/** + * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object. + * @inode: the VFS 'struct inode' pointer + */ +static inline struct ubifs_inode *ubifs_inode(const struct inode *inode) +{ + return container_of(inode, struct ubifs_inode, vfs_inode); +} + +/** + * ubifs_wbuf_sync - synchronize write-buffer. + * @wbuf: write-buffer to synchronize + * + * This is the same as 'ubifs_wbuf_sync_nolock()' but it does not assume + * that the write-buffer is already locked. + */ +static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf) +{ + int err; + + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + err = ubifs_wbuf_sync_nolock(wbuf); + mutex_unlock(&wbuf->io_mutex); + return err; +} + +/** + * ubifs_add_dirt - add dirty space to LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to add dirty space for + * @dirty: dirty space to add + * + * This is a helper function which increased amount of dirty LEB space. Returns + * zero in case of success and a negative error code in case of failure. + */ +static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty) +{ + return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0); +} + +/** + * ubifs_return_leb - return LEB to lprops. + * @c: the UBIFS file-system description object + * @lnum: LEB to return + * + * This helper function cleans the "taken" flag of a logical eraseblock in the + * lprops. Returns zero in case of success and a negative error code in case of + * failure. + */ +static inline int ubifs_return_leb(struct ubifs_info *c, int lnum) +{ + return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0, + LPROPS_TAKEN, 0); +} + +/** + * ubifs_idx_node_sz - return index node size. + * @c: the UBIFS file-system description object + * @child_cnt: number of children of this index node + */ +static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt) +{ + return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len + c->hash_len) + * child_cnt; +} + +/** + * ubifs_idx_branch - return pointer to an index branch. + * @c: the UBIFS file-system description object + * @idx: index node + * @bnum: branch number + */ +static inline +struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c, + const struct ubifs_idx_node *idx, + int bnum) +{ + return (struct ubifs_branch *)((void *)idx->branches + + (UBIFS_BRANCH_SZ + c->key_len + c->hash_len) * bnum); +} + +/** + * ubifs_idx_key - return pointer to an index key. + * @c: the UBIFS file-system description object + * @idx: index node + */ +static inline void *ubifs_idx_key(__unused const struct ubifs_info *c, + const struct ubifs_idx_node *idx) +{ + return (void *)((struct ubifs_branch *)idx->branches)->key; +} + +/** + * ubifs_tnc_lookup - look up a file-system node. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * + * This function look up and reads node with key @key. The caller has to make + * sure the @node buffer is large enough to fit the node. Returns zero in case + * of success, %-ENOENT if the node was not found, and a negative error code in + * case of failure. + */ +static inline int ubifs_tnc_lookup(struct ubifs_info *c, + const union ubifs_key *key, void *node) +{ + return ubifs_tnc_locate(c, key, node, NULL, NULL); +} + +/** + * ubifs_get_lprops - get reference to LEB properties. + * @c: the UBIFS file-system description object + * + * This function locks lprops. Lprops have to be unlocked by + * 'ubifs_release_lprops()'. + */ +static inline void ubifs_get_lprops(struct ubifs_info *c) +{ + mutex_lock(&c->lp_mutex); +} + +/** + * ubifs_release_lprops - release lprops lock. + * @c: the UBIFS file-system description object + * + * This function has to be called after each 'ubifs_get_lprops()' call to + * unlock lprops. + */ +static inline void ubifs_release_lprops(struct ubifs_info *c) +{ + ubifs_assert(c, mutex_is_locked(&c->lp_mutex)); + ubifs_assert(c, c->lst.empty_lebs >= 0 && + c->lst.empty_lebs <= c->main_lebs); + mutex_unlock(&c->lp_mutex); +} + +/** + * ubifs_next_log_lnum - switch to the next log LEB. + * @c: UBIFS file-system description object + * @lnum: current log LEB + * + * This helper function returns the log LEB number which goes next after LEB + * 'lnum'. + */ +static inline int ubifs_next_log_lnum(const struct ubifs_info *c, int lnum) +{ + lnum += 1; + if (lnum > c->log_last) + lnum = UBIFS_LOG_LNUM; + + return lnum; +} + +#endif /* __UBIFS_MISC_H__ */ diff --git a/ubifs-utils/libubifs/orphan.c b/ubifs-utils/libubifs/orphan.c new file mode 100644 index 0000000..baa4db7 --- /dev/null +++ b/ubifs-utils/libubifs/orphan.c @@ -0,0 +1,644 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Author: Adrian Hunter + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/* + * An orphan is an inode number whose inode node has been committed to the index + * with a link count of zero. That happens when an open file is deleted + * (unlinked) and then a commit is run. In the normal course of events the inode + * would be deleted when the file is closed. However in the case of an unclean + * unmount, orphans need to be accounted for. After an unclean unmount, the + * orphans' inodes must be deleted which means either scanning the entire index + * looking for them, or keeping a list on flash somewhere. This unit implements + * the latter approach. + * + * The orphan area is a fixed number of LEBs situated between the LPT area and + * the main area. The number of orphan area LEBs is specified when the file + * system is created. The minimum number is 1. The size of the orphan area + * should be so that it can hold the maximum number of orphans that are expected + * to ever exist at one time. + * + * The number of orphans that can fit in a LEB is: + * + * (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64) + * + * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough. + * + * Orphans are accumulated in a rb-tree. When an inode's link count drops to + * zero, the inode number is added to the rb-tree. It is removed from the tree + * when the inode is deleted. Any new orphans that are in the orphan tree when + * the commit is run, are written to the orphan area in 1 or more orphan nodes. + * If the orphan area is full, it is consolidated to make space. There is + * always enough space because validation prevents the user from creating more + * than the maximum number of orphans allowed. + */ + +static int dbg_check_orphans(struct ubifs_info *c); + +/** + * ubifs_orphan_start_commit - start commit of orphans. + * @c: UBIFS file-system description object + * + * Start commit of orphans. + */ +int ubifs_orphan_start_commit(struct ubifs_info *c) +{ + struct ubifs_orphan *orphan, **last; + + spin_lock(&c->orphan_lock); + last = &c->orph_cnext; + list_for_each_entry(orphan, &c->orph_new, new_list) { + ubifs_assert(c, orphan->new); + ubifs_assert(c, !orphan->cmt); + orphan->new = 0; + orphan->cmt = 1; + *last = orphan; + last = &orphan->cnext; + } + *last = NULL; + c->cmt_orphans = c->new_orphans; + c->new_orphans = 0; + dbg_cmt("%d orphans to commit", c->cmt_orphans); + INIT_LIST_HEAD(&c->orph_new); + if (c->tot_orphans == 0) + c->no_orphs = 1; + else + c->no_orphs = 0; + spin_unlock(&c->orphan_lock); + return 0; +} + +/** + * avail_orphs - calculate available space. + * @c: UBIFS file-system description object + * + * This function returns the number of orphans that can be written in the + * available space. + */ +static int avail_orphs(struct ubifs_info *c) +{ + int avail_lebs, avail, gap; + + avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1; + avail = avail_lebs * + ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)); + gap = c->leb_size - c->ohead_offs; + if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64)) + avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64); + return avail; +} + +/** + * tot_avail_orphs - calculate total space. + * @c: UBIFS file-system description object + * + * This function returns the number of orphans that can be written in half + * the total space. That leaves half the space for adding new orphans. + */ +static int tot_avail_orphs(struct ubifs_info *c) +{ + int avail_lebs, avail; + + avail_lebs = c->orph_lebs; + avail = avail_lebs * + ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)); + return avail / 2; +} + +/** + * do_write_orph_node - write a node to the orphan head. + * @c: UBIFS file-system description object + * @len: length of node + * @atomic: write atomically + * + * This function writes a node to the orphan head from the orphan buffer. If + * %atomic is not zero, then the write is done atomically. On success, %0 is + * returned, otherwise a negative error code is returned. + */ +static int do_write_orph_node(struct ubifs_info *c, int len, int atomic) +{ + int err = 0; + + if (atomic) { + ubifs_assert(c, c->ohead_offs == 0); + ubifs_prepare_node(c, c->orph_buf, len, 1); + len = ALIGN(len, c->min_io_size); + err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len); + } else { + if (c->ohead_offs == 0) { + /* Ensure LEB has been unmapped */ + err = ubifs_leb_unmap(c, c->ohead_lnum); + if (err) + return err; + } + err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum, + c->ohead_offs); + } + return err; +} + +/** + * write_orph_node - write an orphan node. + * @c: UBIFS file-system description object + * @atomic: write atomically + * + * This function builds an orphan node from the cnext list and writes it to the + * orphan head. On success, %0 is returned, otherwise a negative error code + * is returned. + */ +static int write_orph_node(struct ubifs_info *c, int atomic) +{ + struct ubifs_orphan *orphan, *cnext; + struct ubifs_orph_node *orph; + int gap, err, len, cnt, i; + + ubifs_assert(c, c->cmt_orphans > 0); + gap = c->leb_size - c->ohead_offs; + if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) { + c->ohead_lnum += 1; + c->ohead_offs = 0; + gap = c->leb_size; + if (c->ohead_lnum > c->orph_last) { + /* + * We limit the number of orphans so that this should + * never happen. + */ + ubifs_err(c, "out of space in orphan area"); + return -EINVAL; + } + } + cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64); + if (cnt > c->cmt_orphans) + cnt = c->cmt_orphans; + len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64); + ubifs_assert(c, c->orph_buf); + orph = c->orph_buf; + orph->ch.node_type = UBIFS_ORPH_NODE; + spin_lock(&c->orphan_lock); + cnext = c->orph_cnext; + for (i = 0; i < cnt; i++) { + orphan = cnext; + ubifs_assert(c, orphan->cmt); + orph->inos[i] = cpu_to_le64(orphan->inum); + orphan->cmt = 0; + cnext = orphan->cnext; + orphan->cnext = NULL; + } + c->orph_cnext = cnext; + c->cmt_orphans -= cnt; + spin_unlock(&c->orphan_lock); + if (c->cmt_orphans) + orph->cmt_no = cpu_to_le64(c->cmt_no); + else + /* Mark the last node of the commit */ + orph->cmt_no = cpu_to_le64((c->cmt_no) | (1ULL << 63)); + ubifs_assert(c, c->ohead_offs + len <= c->leb_size); + ubifs_assert(c, c->ohead_lnum >= c->orph_first); + ubifs_assert(c, c->ohead_lnum <= c->orph_last); + err = do_write_orph_node(c, len, atomic); + c->ohead_offs += ALIGN(len, c->min_io_size); + c->ohead_offs = ALIGN(c->ohead_offs, 8); + return err; +} + +/** + * write_orph_nodes - write orphan nodes until there are no more to commit. + * @c: UBIFS file-system description object + * @atomic: write atomically + * + * This function writes orphan nodes for all the orphans to commit. On success, + * %0 is returned, otherwise a negative error code is returned. + */ +static int write_orph_nodes(struct ubifs_info *c, int atomic) +{ + int err; + + while (c->cmt_orphans > 0) { + err = write_orph_node(c, atomic); + if (err) + return err; + } + if (atomic) { + int lnum; + + /* Unmap any unused LEBs after consolidation */ + for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + } + return 0; +} + +/** + * consolidate - consolidate the orphan area. + * @c: UBIFS file-system description object + * + * This function enables consolidation by putting all the orphans into the list + * to commit. The list is in the order that the orphans were added, and the + * LEBs are written atomically in order, so at no time can orphans be lost by + * an unclean unmount. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int consolidate(struct ubifs_info *c) +{ + int tot_avail = tot_avail_orphs(c), err = 0; + + spin_lock(&c->orphan_lock); + dbg_cmt("there is space for %d orphans and there are %d", + tot_avail, c->tot_orphans); + if (c->tot_orphans - c->new_orphans <= tot_avail) { + struct ubifs_orphan *orphan, **last; + int cnt = 0; + + /* Change the cnext list to include all non-new orphans */ + last = &c->orph_cnext; + list_for_each_entry(orphan, &c->orph_list, list) { + if (orphan->new) + continue; + orphan->cmt = 1; + *last = orphan; + last = &orphan->cnext; + cnt += 1; + } + *last = NULL; + ubifs_assert(c, cnt == c->tot_orphans - c->new_orphans); + c->cmt_orphans = cnt; + c->ohead_lnum = c->orph_first; + c->ohead_offs = 0; + } else { + /* + * We limit the number of orphans so that this should + * never happen. + */ + ubifs_err(c, "out of space in orphan area"); + err = -EINVAL; + } + spin_unlock(&c->orphan_lock); + return err; +} + +/** + * commit_orphans - commit orphans. + * @c: UBIFS file-system description object + * + * This function commits orphans to flash. On success, %0 is returned, + * otherwise a negative error code is returned. + */ +static int commit_orphans(struct ubifs_info *c) +{ + int avail, atomic = 0, err; + + ubifs_assert(c, c->cmt_orphans > 0); + avail = avail_orphs(c); + if (avail < c->cmt_orphans) { + /* Not enough space to write new orphans, so consolidate */ + err = consolidate(c); + if (err) + return err; + atomic = 1; + } + err = write_orph_nodes(c, atomic); + return err; +} + +/** + * erase_deleted - erase the orphans marked for deletion. + * @c: UBIFS file-system description object + * + * During commit, the orphans being committed cannot be deleted, so they are + * marked for deletion and deleted by this function. Also, the recovery + * adds killed orphans to the deletion list, and therefore they are deleted + * here too. + */ +static void erase_deleted(struct ubifs_info *c) +{ + struct ubifs_orphan *orphan, *dnext; + + spin_lock(&c->orphan_lock); + dnext = c->orph_dnext; + while (dnext) { + orphan = dnext; + dnext = orphan->dnext; + ubifs_assert(c, !orphan->new); + ubifs_assert(c, orphan->del); + list_del(&orphan->list); + c->tot_orphans -= 1; + dbg_gen("deleting orphan ino %lu", (unsigned long)orphan->inum); + kfree(orphan); + } + c->orph_dnext = NULL; + spin_unlock(&c->orphan_lock); +} + +/** + * ubifs_orphan_end_commit - end commit of orphans. + * @c: UBIFS file-system description object + * + * End commit of orphans. + */ +int ubifs_orphan_end_commit(struct ubifs_info *c) +{ + int err; + + if (c->cmt_orphans != 0) { + err = commit_orphans(c); + if (err) + return err; + } + erase_deleted(c); + err = dbg_check_orphans(c); + return err; +} + +/** + * ubifs_clear_orphans - erase all LEBs used for orphans. + * @c: UBIFS file-system description object + * + * If recovery is not required, then the orphans from the previous session + * are not needed. This function locates the LEBs used to record + * orphans, and un-maps them. + */ +int ubifs_clear_orphans(struct ubifs_info *c) +{ + int lnum, err; + + for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + c->ohead_lnum = c->orph_first; + c->ohead_offs = 0; + return 0; +} + +/** + * do_kill_orphans - remove orphan inodes from the index. + * @c: UBIFS file-system description object + * @sleb: scanned LEB + * @last_cmt_no: cmt_no of last orphan node read is passed and returned here + * @outofdate: whether the LEB is out of date is returned here + * @last_flagged: whether the end orphan node is encountered + * + * This function is a helper to the 'kill_orphans()' function. It goes through + * every orphan node in a LEB and for every inode number recorded, removes + * all keys for that inode from the TNC. + */ +static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb, + unsigned long long *last_cmt_no, int *outofdate, + int *last_flagged) +{ + struct ubifs_scan_node *snod; + struct ubifs_orph_node *orph; + struct ubifs_ino_node *ino = NULL; + unsigned long long cmt_no; + ino_t inum; + int i, n, err, first = 1; + + ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS); + if (!ino) + return -ENOMEM; + + list_for_each_entry(snod, &sleb->nodes, list) { + if (snod->type != UBIFS_ORPH_NODE) { + ubifs_err(c, "invalid node type %d in orphan area at %d:%d", + snod->type, sleb->lnum, snod->offs); + ubifs_dump_node(c, snod->node, + c->leb_size - snod->offs); + err = -EINVAL; + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + goto out_free; + } + + orph = snod->node; + + /* Check commit number */ + cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX; + /* + * The commit number on the master node may be less, because + * of a failed commit. If there are several failed commits in a + * row, the commit number written on orphan nodes will continue + * to increase (because the commit number is adjusted here) even + * though the commit number on the master node stays the same + * because the master node has not been re-written. + */ + if (cmt_no > c->cmt_no) + c->cmt_no = cmt_no; + if (cmt_no < *last_cmt_no && *last_flagged) { + /* + * The last orphan node had a higher commit number and + * was flagged as the last written for that commit + * number. That makes this orphan node, out of date. + */ + if (!first) { + ubifs_err(c, "out of order commit number %llu in orphan node at %d:%d", + cmt_no, sleb->lnum, snod->offs); + ubifs_dump_node(c, snod->node, + c->leb_size - snod->offs); + err = -EINVAL; + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + goto out_free; + } + dbg_rcvry("out of date LEB %d", sleb->lnum); + *outofdate = 1; + err = 0; + goto out_free; + } + + if (first) + first = 0; + + n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3; + for (i = 0; i < n; i++) { + union ubifs_key key; + + inum = le64_to_cpu(orph->inos[i]); + + ino_key_init(c, &key, inum); + err = ubifs_tnc_lookup(c, &key, ino); + if (err && err != -ENOENT) { + unsigned int reason; + + reason = get_failure_reason_callback(c); + if (reason & FR_DATA_CORRUPTED) { + test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED); + if (handle_failure_callback(c, FR_H_TNC_DATA_CORRUPTED, NULL)) { + /* Leave the inode to be deleted by subsequent steps */ + continue; + } + } + goto out_free; + } + + /* + * Check whether an inode can really get deleted. + * linkat() with O_TMPFILE allows rebirth of an inode. + */ + if (err == 0 && ino->nlink == 0) { + dbg_rcvry("deleting orphaned inode %lu", + (unsigned long)inum); + + err = ubifs_tnc_remove_ino(c, inum); + if (err) { + if (c->program_type == FSCK_PROGRAM_TYPE) + goto out_free; + goto out_ro; + } + } + } + + *last_cmt_no = cmt_no; + if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) { + dbg_rcvry("last orph node for commit %llu at %d:%d", + cmt_no, sleb->lnum, snod->offs); + *last_flagged = 1; + } else + *last_flagged = 0; + } + + err = 0; +out_free: + kfree(ino); + return err; + +out_ro: + ubifs_ro_mode(c, err); + kfree(ino); + return err; +} + +/** + * kill_orphans - remove all orphan inodes from the index. + * @c: UBIFS file-system description object + * + * If recovery is required, then orphan inodes recorded during the previous + * session (which ended with an unclean unmount) must be deleted from the index. + * This is done by updating the TNC, but since the index is not updated until + * the next commit, the LEBs where the orphan information is recorded are not + * erased until the next commit. + */ +static int kill_orphans(struct ubifs_info *c) +{ + unsigned long long last_cmt_no = 0; + int lnum, err = 0, outofdate = 0, last_flagged = 0; + + c->ohead_lnum = c->orph_first; + c->ohead_offs = 0; + /* Check no-orphans flag and skip this if no orphans */ + if (c->no_orphs) { + dbg_rcvry("no orphans"); + return 0; + } + /* + * Orph nodes always start at c->orph_first and are written to each + * successive LEB in turn. Generally unused LEBs will have been unmapped + * but may contain out of date orphan nodes if the unmap didn't go + * through. In addition, the last orphan node written for each commit is + * marked (top bit of orph->cmt_no is set to 1). It is possible that + * there are orphan nodes from the next commit (i.e. the commit did not + * complete successfully). In that case, no orphans will have been lost + * due to the way that orphans are written, and any orphans added will + * be valid orphans anyway and so can be deleted. + */ + for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { + struct ubifs_scan_leb *sleb; + + dbg_rcvry("LEB %d", lnum); + sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1); + if (IS_ERR(sleb)) { + if (PTR_ERR(sleb) == -EUCLEAN) { + clear_failure_reason_callback(c); + sleb = ubifs_recover_leb(c, lnum, 0, + c->sbuf, -1); + } + if (IS_ERR(sleb)) { + if (test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED) && + handle_failure_callback(c, FR_H_ORPHAN_CORRUPTED, &lnum)) { + /* Skip the orphan LEB. */ + continue; + } + err = PTR_ERR(sleb); + break; + } + } + err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate, + &last_flagged); + if (err) { + unsigned int reason = get_failure_reason_callback(c); + + if (reason & FR_DATA_CORRUPTED) { + test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED); + if (handle_failure_callback(c, FR_H_ORPHAN_CORRUPTED, &lnum)) { + err = 0; + /* Skip the orphan LEB. */ + ubifs_scan_destroy(sleb); + continue; + } + } + ubifs_scan_destroy(sleb); + break; + } + if (outofdate) { + ubifs_scan_destroy(sleb); + break; + } + if (sleb->endpt) { + c->ohead_lnum = lnum; + c->ohead_offs = sleb->endpt; + } + ubifs_scan_destroy(sleb); + } + return err; +} + +/** + * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them. + * @c: UBIFS file-system description object + * @unclean: indicates recovery from unclean unmount + * @read_only: indicates read only mount + * + * This function is called when mounting to erase orphans from the previous + * session. If UBIFS was not unmounted cleanly, then the inodes recorded as + * orphans are deleted. + */ +int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only) +{ + int err = 0; + + c->max_orphans = tot_avail_orphs(c); + + if (!read_only) { + c->orph_buf = vmalloc(c->leb_size); + if (!c->orph_buf) + return -ENOMEM; + } + + if (unclean) + err = kill_orphans(c); + else if (!read_only) + err = ubifs_clear_orphans(c); + + return err; +} + +static int dbg_check_orphans(__unused struct ubifs_info *c) +{ + return 0; +} diff --git a/ubifs-utils/libubifs/recovery.c b/ubifs-utils/libubifs/recovery.c new file mode 100644 index 0000000..905e164 --- /dev/null +++ b/ubifs-utils/libubifs/recovery.c @@ -0,0 +1,1404 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements functions needed to recover from unclean un-mounts. + * When UBIFS is mounted, it checks a flag on the master node to determine if + * an un-mount was completed successfully. If not, the process of mounting + * incorporates additional checking and fixing of on-flash data structures. + * UBIFS always cleans away all remnants of an unclean un-mount, so that + * errors do not accumulate. However UBIFS defers recovery if it is mounted + * read-only, and the flash is not modified in that case. + * + * The general UBIFS approach to the recovery is that it recovers from + * corruptions which could be caused by power cuts, but it refuses to recover + * from corruption caused by other reasons. And UBIFS tries to distinguish + * between these 2 reasons of corruptions and silently recover in the former + * case and loudly complain in the latter case. + * + * UBIFS writes only to erased LEBs, so it writes only to the flash space + * containing only 0xFFs. UBIFS also always writes strictly from the beginning + * of the LEB to the end. And UBIFS assumes that the underlying flash media + * writes in @c->max_write_size bytes at a time. + * + * Hence, if UBIFS finds a corrupted node at offset X, it expects only the min. + * I/O unit corresponding to offset X to contain corrupted data, all the + * following min. I/O units have to contain empty space (all 0xFFs). If this is + * not true, the corruption cannot be the result of a power cut, and UBIFS + * refuses to mount. + */ + +#include <sys/types.h> + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "crc32.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/** + * is_empty - determine whether a buffer is empty (contains all 0xff). + * @buf: buffer to clean + * @len: length of buffer + * + * This function returns %1 if the buffer is empty (contains all 0xff) otherwise + * %0 is returned. + */ +static int is_empty(void *buf, int len) +{ + uint8_t *p = buf; + int i; + + for (i = 0; i < len; i++) + if (*p++ != 0xff) + return 0; + return 1; +} + +/** + * first_non_ff - find offset of the first non-0xff byte. + * @buf: buffer to search in + * @len: length of buffer + * + * This function returns offset of the first non-0xff byte in @buf or %-1 if + * the buffer contains only 0xff bytes. + */ +static int first_non_ff(void *buf, int len) +{ + uint8_t *p = buf; + int i; + + for (i = 0; i < len; i++) + if (*p++ != 0xff) + return i; + return -1; +} + +/** + * get_master_node - get the last valid master node allowing for corruption. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @pbuf: buffer containing the LEB read, is returned here + * @mst: master node, if found, is returned here + * @cor: corruption, if found, is returned here + * + * This function allocates a buffer, reads the LEB into it, and finds and + * returns the last valid master node allowing for one area of corruption. + * The corrupt area, if there is one, must be consistent with the assumption + * that it is the result of an unclean unmount while the master node was being + * written. Under those circumstances, it is valid to use the previously written + * master node. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf, + struct ubifs_mst_node **mst, void **cor) +{ + const int sz = c->mst_node_alsz; + int err, offs, len; + void *sbuf, *buf; + + sbuf = vmalloc(c->leb_size); + if (!sbuf) + return -ENOMEM; + + err = ubifs_leb_read(c, lnum, sbuf, 0, c->leb_size, 0); + if (err && err != -EBADMSG) + goto out_free; + + /* Find the first position that is definitely not a node */ + offs = 0; + buf = sbuf; + len = c->leb_size; + while (offs + UBIFS_MST_NODE_SZ <= c->leb_size) { + struct ubifs_ch *ch = buf; + + if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) + break; + offs += sz; + buf += sz; + len -= sz; + } + /* See if there was a valid master node before that */ + if (offs) { + int ret; + + offs -= sz; + buf -= sz; + len += sz; + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1); + if (ret != SCANNED_A_NODE && offs) { + /* Could have been corruption so check one place back */ + offs -= sz; + buf -= sz; + len += sz; + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1); + if (ret != SCANNED_A_NODE) + /* + * We accept only one area of corruption because + * we are assuming that it was caused while + * trying to write a master node. + */ + goto out_err; + } + if (ret == SCANNED_A_NODE) { + struct ubifs_ch *ch = buf; + + if (ch->node_type != UBIFS_MST_NODE) + goto out_err; + dbg_rcvry("found a master node at %d:%d", lnum, offs); + *mst = buf; + offs += sz; + buf += sz; + len -= sz; + } + } + /* Check for corruption */ + if (offs < c->leb_size) { + if (!is_empty(buf, min_t(int, len, sz))) { + *cor = buf; + dbg_rcvry("found corruption at %d:%d", lnum, offs); + } + offs += sz; + buf += sz; + len -= sz; + } + /* Check remaining empty space */ + if (offs < c->leb_size) + if (!is_empty(buf, len)) + goto out_err; + *pbuf = sbuf; + return 0; + +out_err: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + err = -EINVAL; +out_free: + vfree(sbuf); + *mst = NULL; + *cor = NULL; + return err; +} + +/** + * write_rcvrd_mst_node - write recovered master node. + * @c: UBIFS file-system description object + * @mst: master node + * + * This function returns %0 on success and a negative error code on failure. + */ +static int write_rcvrd_mst_node(struct ubifs_info *c, + struct ubifs_mst_node *mst) +{ + int err = 0, lnum = UBIFS_MST_LNUM, sz = c->mst_node_alsz; + __le32 save_flags; + + dbg_rcvry("recovery"); + + save_flags = mst->flags; + mst->flags |= cpu_to_le32(UBIFS_MST_RCVRY); + + err = ubifs_prepare_node_hmac(c, mst, UBIFS_MST_NODE_SZ, + offsetof(struct ubifs_mst_node, hmac), 1); + if (err) + goto out; + err = ubifs_leb_change(c, lnum, mst, sz); + if (err) + goto out; + err = ubifs_leb_change(c, lnum + 1, mst, sz); + if (err) + goto out; +out: + mst->flags = save_flags; + return err; +} + +/** + * ubifs_recover_master_node - recover the master node. + * @c: UBIFS file-system description object + * + * This function recovers the master node from corruption that may occur due to + * an unclean unmount. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_master_node(struct ubifs_info *c) +{ + void *buf1 = NULL, *buf2 = NULL, *cor1 = NULL, *cor2 = NULL; + struct ubifs_mst_node *mst1 = NULL, *mst2 = NULL, *mst; + const int sz = c->mst_node_alsz; + int err, offs1, offs2; + + dbg_rcvry("recovery"); + + err = get_master_node(c, UBIFS_MST_LNUM, &buf1, &mst1, &cor1); + if (err) + goto out_free; + + err = get_master_node(c, UBIFS_MST_LNUM + 1, &buf2, &mst2, &cor2); + if (err) + goto out_free; + + if (mst1) { + offs1 = (void *)mst1 - buf1; + if ((le32_to_cpu(mst1->flags) & UBIFS_MST_RCVRY) && + (offs1 == 0 && !cor1)) { + /* + * mst1 was written by recovery at offset 0 with no + * corruption. + */ + dbg_rcvry("recovery recovery"); + mst = mst1; + } else if (mst2) { + offs2 = (void *)mst2 - buf2; + if (offs1 == offs2) { + /* Same offset, so must be the same */ + if (ubifs_compare_master_node(c, mst1, mst2)) + goto out_err; + mst = mst1; + } else if (offs2 + sz == offs1) { + /* 1st LEB was written, 2nd was not */ + if (cor1) + goto out_err; + mst = mst1; + } else if (offs1 == 0 && + c->leb_size - offs2 - sz < sz) { + /* 1st LEB was unmapped and written, 2nd not */ + if (cor1) + goto out_err; + mst = mst1; + } else + goto out_err; + } else { + /* + * 2nd LEB was unmapped and about to be written, so + * there must be only one master node in the first LEB + * and no corruption. + */ + if (offs1 != 0 || cor1) + goto out_err; + mst = mst1; + } + } else { + if (!mst2) + goto out_err; + /* + * 1st LEB was unmapped and about to be written, so there must + * be no room left in 2nd LEB. + */ + offs2 = (void *)mst2 - buf2; + if (offs2 + sz + sz <= c->leb_size) + goto out_err; + mst = mst2; + } + + ubifs_msg(c, "recovered master node from LEB %d", + (mst == mst1 ? UBIFS_MST_LNUM : UBIFS_MST_LNUM + 1)); + + memcpy(c->mst_node, mst, UBIFS_MST_NODE_SZ); + + if (c->ro_mount) { + /* Read-only mode. Keep a copy for switching to rw mode */ + c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL); + if (!c->rcvrd_mst_node) { + err = -ENOMEM; + goto out_free; + } + memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ); + + /* + * We had to recover the master node, which means there was an + * unclean reboot. However, it is possible that the master node + * is clean at this point, i.e., %UBIFS_MST_DIRTY is not set. + * E.g., consider the following chain of events: + * + * 1. UBIFS was cleanly unmounted, so the master node is clean + * 2. UBIFS is being mounted R/W and starts changing the master + * node in the first (%UBIFS_MST_LNUM). A power cut happens, + * so this LEB ends up with some amount of garbage at the + * end. + * 3. UBIFS is being mounted R/O. We reach this place and + * recover the master node from the second LEB + * (%UBIFS_MST_LNUM + 1). But we cannot update the media + * because we are being mounted R/O. We have to defer the + * operation. + * 4. However, this master node (@c->mst_node) is marked as + * clean (since the step 1). And if we just return, the + * mount code will be confused and won't recover the master + * node when it is re-mounter R/W later. + * + * Thus, to force the recovery by marking the master node as + * dirty. + */ + c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY); + } else { + /* Write the recovered master node */ + c->max_sqnum = le64_to_cpu(mst->ch.sqnum) - 1; + err = write_rcvrd_mst_node(c, c->mst_node); + if (err) + goto out_free; + } + + vfree(buf2); + vfree(buf1); + + return 0; + +out_err: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + err = -EINVAL; +out_free: + ubifs_err(c, "failed to recover master node"); + if (mst1) { + ubifs_err(c, "dumping first master node"); + ubifs_dump_node(c, mst1, c->leb_size - ((void *)mst1 - buf1)); + } + if (mst2) { + ubifs_err(c, "dumping second master node"); + ubifs_dump_node(c, mst2, c->leb_size - ((void *)mst2 - buf2)); + } + vfree(buf2); + vfree(buf1); + return err; +} + +/** + * is_last_write - determine if an offset was in the last write to a LEB. + * @c: UBIFS file-system description object + * @buf: buffer to check + * @offs: offset to check + * + * This function returns %1 if @offs was in the last write to the LEB whose data + * is in @buf, otherwise %0 is returned. The determination is made by checking + * for subsequent empty space starting from the next @c->max_write_size + * boundary. + */ +static int is_last_write(const struct ubifs_info *c, void *buf, int offs) +{ + int empty_offs, check_len; + uint8_t *p; + + /* + * Round up to the next @c->max_write_size boundary i.e. @offs is in + * the last wbuf written. After that should be empty space. + */ + empty_offs = ALIGN(offs + 1, c->max_write_size); + check_len = c->leb_size - empty_offs; + p = buf + empty_offs - offs; + return is_empty(p, check_len); +} + +/** + * clean_buf - clean the data from an LEB sitting in a buffer. + * @c: UBIFS file-system description object + * @buf: buffer to clean + * @lnum: LEB number to clean + * @offs: offset from which to clean + * @len: length of buffer + * + * This function pads up to the next min_io_size boundary (if there is one) and + * sets empty space to all 0xff. @buf, @offs and @len are updated to the next + * @c->min_io_size boundary. + */ +static void clean_buf(const struct ubifs_info *c, void **buf, int lnum, + int *offs, int *len) +{ + int empty_offs, pad_len; + + dbg_rcvry("cleaning corruption at %d:%d", lnum, *offs); + + ubifs_assert(c, !(*offs & 7)); + empty_offs = ALIGN(*offs, c->min_io_size); + pad_len = empty_offs - *offs; + ubifs_pad(c, *buf, pad_len); + *offs += pad_len; + *buf += pad_len; + *len -= pad_len; + memset(*buf, 0xff, c->leb_size - empty_offs); +} + +/** + * no_more_nodes - determine if there are no more nodes in a buffer. + * @c: UBIFS file-system description object + * @buf: buffer to check + * @len: length of buffer + * @lnum: LEB number of the LEB from which @buf was read + * @offs: offset from which @buf was read + * + * This function ensures that the corrupted node at @offs is the last thing + * written to a LEB. This function returns %1 if more data is not found and + * %0 if more data is found. + */ +static int no_more_nodes(const struct ubifs_info *c, void *buf, int len, + int lnum, int offs) +{ + struct ubifs_ch *ch = buf; + int skip, dlen = le32_to_cpu(ch->len); + + /* Check for empty space after the corrupt node's common header */ + skip = ALIGN(offs + UBIFS_CH_SZ, c->max_write_size) - offs; + if (is_empty(buf + skip, len - skip)) + return 1; + /* + * The area after the common header size is not empty, so the common + * header must be intact. Check it. + */ + if (ubifs_check_node(c, buf, len, lnum, offs, 1, 0) != -EUCLEAN) { + dbg_rcvry("unexpected bad common header at %d:%d", lnum, offs); + return 0; + } + /* Now we know the corrupt node's length we can skip over it */ + skip = ALIGN(offs + dlen, c->max_write_size) - offs; + /* After which there should be empty space */ + if (is_empty(buf + skip, len - skip)) + return 1; + dbg_rcvry("unexpected data at %d:%d", lnum, offs + skip); + return 0; +} + +/** + * fix_unclean_leb - fix an unclean LEB. + * @c: UBIFS file-system description object + * @sleb: scanned LEB information + * @start: offset where scan started + */ +static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb, + int start) +{ + int lnum = sleb->lnum, endpt = start; + + /* Get the end offset of the last node we are keeping */ + if (!list_empty(&sleb->nodes)) { + struct ubifs_scan_node *snod; + + snod = list_entry(sleb->nodes.prev, + struct ubifs_scan_node, list); + endpt = snod->offs + snod->len; + } + + if (c->ro_mount && !c->remounting_rw) { + /* Add to recovery list */ + struct ubifs_unclean_leb *ucleb; + + dbg_rcvry("need to fix LEB %d start %d endpt %d", + lnum, start, sleb->endpt); + ucleb = kzalloc(sizeof(struct ubifs_unclean_leb), GFP_NOFS); + if (!ucleb) + return -ENOMEM; + ucleb->lnum = lnum; + ucleb->endpt = endpt; + list_add_tail(&ucleb->list, &c->unclean_leb_list); + } else { + /* Write the fixed LEB back to flash */ + int err; + + dbg_rcvry("fixing LEB %d start %d endpt %d", + lnum, start, sleb->endpt); + if (endpt == 0) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } else { + int len = ALIGN(endpt, c->min_io_size); + + if (start) { + err = ubifs_leb_read(c, lnum, sleb->buf, 0, + start, 1); + if (err && err != -EBADMSG) + return err; + } + /* Pad to min_io_size */ + if (len > endpt) { + int pad_len = len - ALIGN(endpt, 8); + + if (pad_len > 0) { + void *buf = sleb->buf + len - pad_len; + + ubifs_pad(c, buf, pad_len); + } + } + err = ubifs_leb_change(c, lnum, sleb->buf, len); + if (err) + return err; + } + } + return 0; +} + +/** + * drop_last_group - drop the last group of nodes. + * @sleb: scanned LEB information + * @offs: offset of dropped nodes is returned here + * + * This is a helper function for 'ubifs_recover_leb()' which drops the last + * group of nodes of the scanned LEB. + */ +static void drop_last_group(struct ubifs_scan_leb *sleb, int *offs) +{ + while (!list_empty(&sleb->nodes)) { + struct ubifs_scan_node *snod; + struct ubifs_ch *ch; + + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, + list); + ch = snod->node; + if (ch->group_type != UBIFS_IN_NODE_GROUP) + break; + + dbg_rcvry("dropping grouped node at %d:%d", + sleb->lnum, snod->offs); + *offs = snod->offs; + list_del(&snod->list); + kfree(snod); + sleb->nodes_cnt -= 1; + } +} + +/** + * drop_last_node - drop the last node. + * @sleb: scanned LEB information + * @offs: offset of dropped nodes is returned here + * + * This is a helper function for 'ubifs_recover_leb()' which drops the last + * node of the scanned LEB. + */ +static void drop_last_node(struct ubifs_scan_leb *sleb, int *offs) +{ + struct ubifs_scan_node *snod; + + if (!list_empty(&sleb->nodes)) { + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, + list); + + dbg_rcvry("dropping last node at %d:%d", + sleb->lnum, snod->offs); + *offs = snod->offs; + list_del(&snod->list); + kfree(snod); + sleb->nodes_cnt -= 1; + } +} + +/** + * ubifs_recover_leb - scan and recover a LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @offs: offset + * @sbuf: LEB-sized buffer to use + * @jhead: journal head number this LEB belongs to (%-1 if the LEB does not + * belong to any journal head) + * + * This function does a scan of a LEB, but caters for errors that might have + * been caused by the unclean unmount from which we are attempting to recover. + * Returns the scanned information on success and a negative error code on + * failure. + */ +struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf, int jhead) +{ + int ret = 0, err, len = c->leb_size - offs, start = offs, min_io_unit; + int grouped = jhead == -1 ? 0 : c->jheads[jhead].grouped; + struct ubifs_scan_leb *sleb; + void *buf = sbuf + offs; + + dbg_rcvry("%d:%d, jhead %d, grouped %d", lnum, offs, jhead, grouped); + + sleb = ubifs_start_scan(c, lnum, offs, sbuf); + if (IS_ERR(sleb)) + return sleb; + + ubifs_assert(c, len >= 8); + while (len >= 8) { + dbg_scan("look at LEB %d:%d (%d bytes left)", + lnum, offs, len); + + cond_resched(); + + /* + * Scan quietly until there is an error from which we cannot + * recover + */ + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1); + if (ret == SCANNED_A_NODE) { + /* A valid node, and not a padding node */ + struct ubifs_ch *ch = buf; + int node_len; + + err = ubifs_add_snod(c, sleb, buf, offs); + if (err) + goto error; + node_len = ALIGN(le32_to_cpu(ch->len), 8); + offs += node_len; + buf += node_len; + len -= node_len; + } else if (ret > 0) { + /* Padding bytes or a valid padding node */ + offs += ret; + buf += ret; + len -= ret; + } else if (ret == SCANNED_EMPTY_SPACE || + ret == SCANNED_GARBAGE || + ret == SCANNED_A_BAD_PAD_NODE || + ret == SCANNED_A_CORRUPT_NODE) { + dbg_rcvry("found corruption (%d) at %d:%d", + ret, lnum, offs); + break; + } else { + ubifs_err(c, "unexpected return value %d", ret); + err = -EINVAL; + goto error; + } + } + + if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE) { + if (!is_last_write(c, buf, offs)) + goto corrupted_rescan; + } else if (ret == SCANNED_A_CORRUPT_NODE) { + if (!no_more_nodes(c, buf, len, lnum, offs)) + goto corrupted_rescan; + } else if (!is_empty(buf, len)) { + if (!is_last_write(c, buf, offs)) { + int corruption = first_non_ff(buf, len); + + /* + * See header comment for this file for more + * explanations about the reasons we have this check. + */ + ubifs_err(c, "corrupt empty space LEB %d:%d, corruption starts at %d", + lnum, offs, corruption); + /* Make sure we dump interesting non-0xFF data */ + offs += corruption; + buf += corruption; + goto corrupted; + } + } + + min_io_unit = round_down(offs, c->min_io_size); + if (grouped) + /* + * If nodes are grouped, always drop the incomplete group at + * the end. + */ + drop_last_group(sleb, &offs); + + if (jhead == GCHD) { + /* + * If this LEB belongs to the GC head then while we are in the + * middle of the same min. I/O unit keep dropping nodes. So + * basically, what we want is to make sure that the last min. + * I/O unit where we saw the corruption is dropped completely + * with all the uncorrupted nodes which may possibly sit there. + * + * In other words, let's name the min. I/O unit where the + * corruption starts B, and the previous min. I/O unit A. The + * below code tries to deal with a situation when half of B + * contains valid nodes or the end of a valid node, and the + * second half of B contains corrupted data or garbage. This + * means that UBIFS had been writing to B just before the power + * cut happened. I do not know how realistic is this scenario + * that half of the min. I/O unit had been written successfully + * and the other half not, but this is possible in our 'failure + * mode emulation' infrastructure at least. + * + * So what is the problem, why we need to drop those nodes? Why + * can't we just clean-up the second half of B by putting a + * padding node there? We can, and this works fine with one + * exception which was reproduced with power cut emulation + * testing and happens extremely rarely. + * + * Imagine the file-system is full, we run GC which starts + * moving valid nodes from LEB X to LEB Y (obviously, LEB Y is + * the current GC head LEB). The @c->gc_lnum is -1, which means + * that GC will retain LEB X and will try to continue. Imagine + * that LEB X is currently the dirtiest LEB, and the amount of + * used space in LEB Y is exactly the same as amount of free + * space in LEB X. + * + * And a power cut happens when nodes are moved from LEB X to + * LEB Y. We are here trying to recover LEB Y which is the GC + * head LEB. We find the min. I/O unit B as described above. + * Then we clean-up LEB Y by padding min. I/O unit. And later + * 'ubifs_rcvry_gc_commit()' function fails, because it cannot + * find a dirty LEB which could be GC'd into LEB Y! Even LEB X + * does not match because the amount of valid nodes there does + * not fit the free space in LEB Y any more! And this is + * because of the padding node which we added to LEB Y. The + * user-visible effect of this which I once observed and + * analysed is that we cannot mount the file-system with + * -ENOSPC error. + * + * So obviously, to make sure that situation does not happen we + * should free min. I/O unit B in LEB Y completely and the last + * used min. I/O unit in LEB Y should be A. This is basically + * what the below code tries to do. + */ + while (offs > min_io_unit) + drop_last_node(sleb, &offs); + } + + buf = sbuf + offs; + len = c->leb_size - offs; + + clean_buf(c, &buf, lnum, &offs, &len); + ubifs_end_scan(c, sleb, lnum, offs); + + err = fix_unclean_leb(c, sleb, start); + if (err) + goto error; + + return sleb; + +corrupted_rescan: + /* Re-scan the corrupted data with verbose messages */ + ubifs_err(c, "corruption %d", ret); + ubifs_scan_a_node(c, buf, len, lnum, offs, 0); +corrupted: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_scanned_corruption(c, lnum, offs, buf); + err = -EUCLEAN; +error: + ubifs_err(c, "LEB %d scanning failed", lnum); + ubifs_scan_destroy(sleb); + return ERR_PTR(err); +} + +/** + * get_cs_sqnum - get commit start sequence number. + * @c: UBIFS file-system description object + * @lnum: LEB number of commit start node + * @offs: offset of commit start node + * @cs_sqnum: commit start sequence number is returned here + * + * This function returns %0 on success and a negative error code on failure. + */ +static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs, + unsigned long long *cs_sqnum) +{ + struct ubifs_cs_node *cs_node = NULL; + int err, ret; + + dbg_rcvry("at %d:%d", lnum, offs); + cs_node = kmalloc(UBIFS_CS_NODE_SZ, GFP_KERNEL); + if (!cs_node) + return -ENOMEM; + if (c->leb_size - offs < UBIFS_CS_NODE_SZ) + goto out_err; + err = ubifs_leb_read(c, lnum, (void *)cs_node, offs, + UBIFS_CS_NODE_SZ, 0); + if (err && err != -EBADMSG) + goto out_free; + ret = ubifs_scan_a_node(c, cs_node, UBIFS_CS_NODE_SZ, lnum, offs, 0); + if (ret != SCANNED_A_NODE) { + ubifs_err(c, "Not a valid node"); + goto out_err; + } + if (cs_node->ch.node_type != UBIFS_CS_NODE) { + ubifs_err(c, "Not a CS node, type is %d", cs_node->ch.node_type); + goto out_err; + } + if (le64_to_cpu(cs_node->cmt_no) != c->cmt_no) { + ubifs_err(c, "CS node cmt_no %llu != current cmt_no %llu", + (unsigned long long)le64_to_cpu(cs_node->cmt_no), + c->cmt_no); + goto out_err; + } + *cs_sqnum = le64_to_cpu(cs_node->ch.sqnum); + dbg_rcvry("commit start sqnum %llu", *cs_sqnum); + kfree(cs_node); + return 0; + +out_err: + err = -EINVAL; + set_failure_reason_callback(c, FR_DATA_CORRUPTED); +out_free: + ubifs_err(c, "failed to get CS sqnum"); + kfree(cs_node); + return err; +} + +/** + * ubifs_recover_log_leb - scan and recover a log LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @offs: offset + * @sbuf: LEB-sized buffer to use + * + * This function does a scan of a LEB, but caters for errors that might have + * been caused by unclean reboots from which we are attempting to recover + * (assume that only the last log LEB can be corrupted by an unclean reboot). + * + * This function returns %0 on success and a negative error code on failure. + */ +struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf) +{ + struct ubifs_scan_leb *sleb; + int next_lnum; + + dbg_rcvry("LEB %d", lnum); + next_lnum = lnum + 1; + if (next_lnum >= UBIFS_LOG_LNUM + c->log_lebs) + next_lnum = UBIFS_LOG_LNUM; + if (next_lnum != c->ltail_lnum) { + /* + * We can only recover at the end of the log, so check that the + * next log LEB is empty or out of date. + */ + sleb = ubifs_scan(c, next_lnum, 0, sbuf, 0); + if (IS_ERR(sleb)) + return sleb; + if (sleb->nodes_cnt) { + struct ubifs_scan_node *snod; + unsigned long long cs_sqnum = c->cs_sqnum; + + snod = list_entry(sleb->nodes.next, + struct ubifs_scan_node, list); + if (cs_sqnum == 0) { + int err; + + err = get_cs_sqnum(c, lnum, offs, &cs_sqnum); + if (err) { + ubifs_scan_destroy(sleb); + return ERR_PTR(err); + } + } + if (snod->sqnum > cs_sqnum) { + ubifs_err(c, "unrecoverable log corruption in LEB %d", + lnum); + ubifs_scan_destroy(sleb); + return ERR_PTR(-EUCLEAN); + } + } + ubifs_scan_destroy(sleb); + } + return ubifs_recover_leb(c, lnum, offs, sbuf, -1); +} + +/** + * recover_head - recover a head. + * @c: UBIFS file-system description object + * @lnum: LEB number of head to recover + * @offs: offset of head to recover + * @sbuf: LEB-sized buffer to use + * + * This function ensures that there is no data on the flash at a head location. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int recover_head(struct ubifs_info *c, int lnum, int offs, void *sbuf) +{ + int len = c->max_write_size, err; + + if (offs + len > c->leb_size) + len = c->leb_size - offs; + + if (!len) + return 0; + + /* Read at the head location and check it is empty flash */ + err = ubifs_leb_read(c, lnum, sbuf, offs, len, 1); + if (err || !is_empty(sbuf, len)) { + dbg_rcvry("cleaning head at %d:%d", lnum, offs); + if (offs == 0) + return ubifs_leb_unmap(c, lnum); + err = ubifs_leb_read(c, lnum, sbuf, 0, offs, 1); + if (err && err != -EBADMSG) + return err; + return ubifs_leb_change(c, lnum, sbuf, offs); + } + + return 0; +} + +/** + * ubifs_recover_inl_heads - recover index and LPT heads. + * @c: UBIFS file-system description object + * @sbuf: LEB-sized buffer to use + * + * This function ensures that there is no data on the flash at the index and + * LPT head locations. + * + * This deals with the recovery of a half-completed journal commit. UBIFS is + * careful never to overwrite the last version of the index or the LPT. Because + * the index and LPT are wandering trees, data from a half-completed commit will + * not be referenced anywhere in UBIFS. The data will be either in LEBs that are + * assumed to be empty and will be unmapped anyway before use, or in the index + * and LPT heads. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_inl_heads(struct ubifs_info *c, void *sbuf) +{ + int err; + + ubifs_assert(c, !c->ro_mount || c->remounting_rw); + + dbg_rcvry("checking index head at %d:%d", c->ihead_lnum, c->ihead_offs); + err = recover_head(c, c->ihead_lnum, c->ihead_offs, sbuf); + if (err) + return err; + + dbg_rcvry("checking LPT head at %d:%d", c->nhead_lnum, c->nhead_offs); + + return recover_head(c, c->nhead_lnum, c->nhead_offs, sbuf); +} + +/** + * grab_empty_leb - grab an empty LEB to use as GC LEB and run commit. + * @c: UBIFS file-system description object + * + * This is a helper function for 'ubifs_rcvry_gc_commit()' which grabs an empty + * LEB to be used as GC LEB (@c->gc_lnum), and then runs the commit. Returns + * zero in case of success and a negative error code in case of failure. + */ +static int grab_empty_leb(struct ubifs_info *c) +{ + int lnum, err; + + /* + * Note, it is very important to first search for an empty LEB and then + * run the commit, not vice-versa. The reason is that there might be + * only one empty LEB at the moment, the one which has been the + * @c->gc_lnum just before the power cut happened. During the regular + * UBIFS operation (not now) @c->gc_lnum is marked as "taken", so no + * one but GC can grab it. But at this moment this single empty LEB is + * not marked as taken, so if we run commit - what happens? Right, the + * commit will grab it and write the index there. Remember that the + * index always expands as long as there is free space, and it only + * starts consolidating when we run out of space. + * + * IOW, if we run commit now, we might not be able to find a free LEB + * after this. + */ + lnum = ubifs_find_free_leb_for_idx(c); + if (lnum < 0) { + ubifs_err(c, "could not find an empty LEB"); + ubifs_dump_lprops(c); + ubifs_dump_budg(c, &c->bi); + return lnum; + } + + /* Reset the index flag */ + err = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0, + LPROPS_INDEX, 0); + if (err) + return err; + + c->gc_lnum = lnum; + dbg_rcvry("found empty LEB %d, run commit", lnum); + + return ubifs_run_commit(c); +} + +/** + * ubifs_rcvry_gc_commit - recover the GC LEB number and run the commit. + * @c: UBIFS file-system description object + * + * Out-of-place garbage collection requires always one empty LEB with which to + * start garbage collection. The LEB number is recorded in c->gc_lnum and is + * written to the master node on unmounting. In the case of an unclean unmount + * the value of gc_lnum recorded in the master node is out of date and cannot + * be used. Instead, recovery must allocate an empty LEB for this purpose. + * However, there may not be enough empty space, in which case it must be + * possible to GC the dirtiest LEB into the GC head LEB. + * + * This function also runs the commit which causes the TNC updates from + * size-recovery and orphans to be written to the flash. That is important to + * ensure correct replay order for subsequent mounts. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_rcvry_gc_commit(struct ubifs_info *c) +{ + struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf; + struct ubifs_lprops lp; + int err; + + dbg_rcvry("GC head LEB %d, offs %d", wbuf->lnum, wbuf->offs); + + c->gc_lnum = -1; + if (wbuf->lnum == -1 || wbuf->offs == c->leb_size) + return grab_empty_leb(c); + + err = ubifs_find_dirty_leb(c, &lp, wbuf->offs, 2); + if (err) { + if (err != -ENOSPC) + return err; + + dbg_rcvry("could not find a dirty LEB"); + return grab_empty_leb(c); + } + + ubifs_assert(c, !(lp.flags & LPROPS_INDEX)); + ubifs_assert(c, lp.free + lp.dirty >= wbuf->offs); + + /* + * We run the commit before garbage collection otherwise subsequent + * mounts will see the GC and orphan deletion in a different order. + */ + dbg_rcvry("committing"); + err = ubifs_run_commit(c); + if (err) + return err; + + dbg_rcvry("GC'ing LEB %d", lp.lnum); + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + err = ubifs_garbage_collect_leb(c, &lp); + if (err >= 0) { + int err2 = ubifs_wbuf_sync_nolock(wbuf); + + if (err2) + err = err2; + } + mutex_unlock(&wbuf->io_mutex); + if (err < 0) { + ubifs_err(c, "GC failed, error %d", err); + if (err == -EAGAIN) + err = -EINVAL; + return err; + } + + ubifs_assert(c, err == LEB_RETAINED); + if (err != LEB_RETAINED) + return -EINVAL; + + err = ubifs_leb_unmap(c, c->gc_lnum); + if (err) + return err; + + dbg_rcvry("allocated LEB %d for GC", lp.lnum); + return 0; +} + +/** + * add_ino - add an entry to the size tree. + * @c: UBIFS file-system description object + * @inum: inode number + * @i_size: size on inode + * @d_size: maximum size based on data nodes + * @exists: indicates whether the inode exists + */ +static int add_ino(struct ubifs_info *c, ino_t inum, loff_t i_size, + loff_t d_size, int exists) +{ + struct rb_node **p = &c->size_tree.rb_node, *parent = NULL; + struct size_entry *e; + + while (*p) { + parent = *p; + e = rb_entry(parent, struct size_entry, rb); + if (inum < e->inum) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + e = kzalloc(sizeof(struct size_entry), GFP_KERNEL); + if (!e) + return -ENOMEM; + + e->inum = inum; + e->i_size = i_size; + e->d_size = d_size; + e->exists = exists; + + rb_link_node(&e->rb, parent, p); + rb_insert_color(&e->rb, &c->size_tree); + + return 0; +} + +/** + * find_ino - find an entry on the size tree. + * @c: UBIFS file-system description object + * @inum: inode number + */ +static struct size_entry *find_ino(struct ubifs_info *c, ino_t inum) +{ + struct rb_node *p = c->size_tree.rb_node; + struct size_entry *e; + + while (p) { + e = rb_entry(p, struct size_entry, rb); + if (inum < e->inum) + p = p->rb_left; + else if (inum > e->inum) + p = p->rb_right; + else + return e; + } + return NULL; +} + +/** + * remove_ino - remove an entry from the size tree. + * @c: UBIFS file-system description object + * @inum: inode number + */ +static void remove_ino(struct ubifs_info *c, ino_t inum) +{ + struct size_entry *e = find_ino(c, inum); + + if (!e) + return; + rb_erase(&e->rb, &c->size_tree); + kfree(e); +} + +/** + * ubifs_destroy_size_tree - free resources related to the size tree. + * @c: UBIFS file-system description object + */ +void ubifs_destroy_size_tree(struct ubifs_info *c) +{ + struct size_entry *e, *n; + + rbtree_postorder_for_each_entry_safe(e, n, &c->size_tree, rb) { + kfree(e); + } + + c->size_tree = RB_ROOT; +} + +/** + * ubifs_recover_size_accum - accumulate inode sizes for recovery. + * @c: UBIFS file-system description object + * @key: node key + * @deletion: node is for a deletion + * @new_size: inode size + * + * This function has two purposes: + * 1) to ensure there are no data nodes that fall outside the inode size + * 2) to ensure there are no data nodes for inodes that do not exist + * To accomplish those purposes, a rb-tree is constructed containing an entry + * for each inode number in the journal that has not been deleted, and recording + * the size from the inode node, the maximum size of any data node (also altered + * by truncations) and a flag indicating a inode number for which no inode node + * was present in the journal. + * + * Note that there is still the possibility that there are data nodes that have + * been committed that are beyond the inode size, however the only way to find + * them would be to scan the entire index. Alternatively, some provision could + * be made to record the size of inodes at the start of commit, which would seem + * very cumbersome for a scenario that is quite unlikely and the only negative + * consequence of which is wasted space. + * + * This functions returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key, + int deletion, loff_t new_size) +{ + ino_t inum = key_inum(c, key); + struct size_entry *e; + int err; + + switch (key_type(c, key)) { + case UBIFS_INO_KEY: + if (deletion) + remove_ino(c, inum); + else { + e = find_ino(c, inum); + if (e) { + e->i_size = new_size; + e->exists = 1; + } else { + err = add_ino(c, inum, new_size, 0, 1); + if (err) + return err; + } + } + break; + case UBIFS_DATA_KEY: + e = find_ino(c, inum); + if (e) { + if (new_size > e->d_size) + e->d_size = new_size; + } else { + err = add_ino(c, inum, 0, new_size, 0); + if (err) + return err; + } + break; + case UBIFS_TRUN_KEY: + e = find_ino(c, inum); + if (e) + e->d_size = new_size; + break; + } + return 0; +} + +/** + * fix_size_in_place - fix inode size in place on flash. + * @c: UBIFS file-system description object + * @e: inode size information for recovery + */ +static int fix_size_in_place(struct ubifs_info *c, struct size_entry *e) +{ + struct ubifs_ino_node *ino = c->sbuf; + unsigned char *p; + union ubifs_key key; + int err, lnum, offs, len; + loff_t i_size; + uint32_t crc; + + /* Locate the inode node LEB number and offset */ + ino_key_init(c, &key, e->inum); + err = ubifs_tnc_locate(c, &key, ino, &lnum, &offs); + if (err) { + unsigned int reason = get_failure_reason_callback(c); + + if (reason & FR_DATA_CORRUPTED) { + test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED); + if (handle_failure_callback(c, FR_H_TNC_DATA_CORRUPTED, NULL)) { + /* Leave the inode to be deleted by subsequent steps */ + return 0; + } + } + goto out; + } + /* + * If the size recorded on the inode node is greater than the size that + * was calculated from nodes in the journal then don't change the inode. + */ + i_size = le64_to_cpu(ino->size); + if (i_size >= e->d_size) + return 0; + /* Read the LEB */ + err = ubifs_leb_read(c, lnum, c->sbuf, 0, c->leb_size, 1); + if (err && err != -EBADMSG) + goto out; + /* Change the size field and recalculate the CRC */ + ino = c->sbuf + offs; + ino->size = cpu_to_le64(e->d_size); + len = le32_to_cpu(ino->ch.len); + crc = crc32(UBIFS_CRC32_INIT, (void *)ino + 8, len - 8); + ino->ch.crc = cpu_to_le32(crc); + /* Work out where data in the LEB ends and free space begins */ + p = c->sbuf; + len = c->leb_size - 1; + while (p[len] == 0xff) + len -= 1; + len = ALIGN(len + 1, c->min_io_size); + /* Atomically write the fixed LEB back again */ + err = ubifs_leb_change(c, lnum, c->sbuf, len); + if (err) + goto out; + dbg_rcvry("inode %lu at %d:%d size %lld -> %lld", + (unsigned long)e->inum, lnum, offs, (long long)i_size, + (long long)e->d_size); + return 0; + +out: + ubifs_warn(c, "inode %lu failed to fix size %lld -> %lld error %d", + (unsigned long)e->inum, (long long)e->i_size, + (long long)e->d_size, err); + return err; +} + +/** + * inode_fix_size - fix inode size + * @c: UBIFS file-system description object + * @e: inode size information for recovery + */ +static int inode_fix_size(struct ubifs_info *c, __unused struct size_entry *e) +{ + /* Don't remove entry, keep it in the size tree. */ + /* Remove this assertion after supporting authentication. */ + ubifs_assert(c, c->ro_mount); + return 0; +} + +/** + * ubifs_recover_size - recover inode size. + * @c: UBIFS file-system description object + * @in_place: If true, do a in-place size fixup + * + * This function attempts to fix inode size discrepancies identified by the + * 'ubifs_recover_size_accum()' function. + * + * This functions returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_size(struct ubifs_info *c, bool in_place) +{ + struct rb_node *this = rb_first(&c->size_tree); + + while (this) { + struct size_entry *e; + int err; + + e = rb_entry(this, struct size_entry, rb); + + this = rb_next(this); + + if (!e->exists) { + union ubifs_key key; + + ino_key_init(c, &key, e->inum); + err = ubifs_tnc_lookup(c, &key, c->sbuf); + if (err && err != -ENOENT) { + unsigned int reason; + + reason = get_failure_reason_callback(c); + if (reason & FR_DATA_CORRUPTED) { + test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED); + if (handle_failure_callback(c, FR_H_TNC_DATA_CORRUPTED, NULL)) { + /* Leave the inode to be deleted by subsequent steps */ + goto delete_entry; + } + } + return err; + } + if (err == -ENOENT) { + /* Remove data nodes that have no inode */ + dbg_rcvry("removing ino %lu", + (unsigned long)e->inum); + err = ubifs_tnc_remove_ino(c, e->inum); + if (err) + return err; + } else { + struct ubifs_ino_node *ino = c->sbuf; + + e->exists = 1; + e->i_size = le64_to_cpu(ino->size); + } + } + + if (e->exists && e->i_size < e->d_size) { + ubifs_assert(c, !(c->ro_mount && in_place)); + + /* + * We found data that is outside the found inode size, + * fixup the inode size + */ + + if (in_place) { + err = fix_size_in_place(c, e); + if (err) + return err; + } else { + err = inode_fix_size(c, e); + if (err) + return err; + continue; + } + } + +delete_entry: + rb_erase(&e->rb, &c->size_tree); + kfree(e); + } + + return 0; +} diff --git a/ubifs-utils/libubifs/replay.c b/ubifs-utils/libubifs/replay.c new file mode 100644 index 0000000..9d61133 --- /dev/null +++ b/ubifs-utils/libubifs/replay.c @@ -0,0 +1,1230 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file contains journal replay code. It runs when the file-system is being + * mounted and requires no locking. + * + * The larger is the journal, the longer it takes to scan it, so the longer it + * takes to mount UBIFS. This is why the journal has limited size which may be + * changed depending on the system requirements. But a larger journal gives + * faster I/O speed because it writes the index less frequently. So this is a + * trade-off. Also, the journal is indexed by the in-memory index (TNC), so the + * larger is the journal, the more memory its index may consume. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/** + * struct replay_entry - replay list entry. + * @lnum: logical eraseblock number of the node + * @offs: node offset + * @len: node length + * @hash: node hash + * @deletion: non-zero if this entry corresponds to a node deletion + * @sqnum: node sequence number + * @list: links the replay list + * @key: node key + * @nm: directory entry name + * @old_size: truncation old size + * @new_size: truncation new size + * + * The replay process first scans all buds and builds the replay list, then + * sorts the replay list in nodes sequence number order, and then inserts all + * the replay entries to the TNC. + */ +struct replay_entry { + int lnum; + int offs; + int len; + u8 hash[UBIFS_HASH_ARR_SZ]; + unsigned int deletion:1; + unsigned long long sqnum; + struct list_head list; + union ubifs_key key; + union { + struct fscrypt_name nm; + struct { + loff_t old_size; + loff_t new_size; + }; + }; +}; + +/** + * struct bud_entry - entry in the list of buds to replay. + * @list: next bud in the list + * @bud: bud description object + * @sqnum: reference node sequence number + * @free: free bytes in the bud + * @dirty: dirty bytes in the bud + */ +struct bud_entry { + struct list_head list; + struct ubifs_bud *bud; + unsigned long long sqnum; + int free; + int dirty; +}; + +/** + * set_bud_lprops - set free and dirty space used by a bud. + * @c: UBIFS file-system description object + * @b: bud entry which describes the bud + * + * This function makes sure the LEB properties of bud @b are set correctly + * after the replay. Returns zero in case of success and a negative error code + * in case of failure. + */ +static int set_bud_lprops(struct ubifs_info *c, struct bud_entry *b) +{ + const struct ubifs_lprops *lp; + int err = 0, dirty; + + if (!test_lpt_valid_callback(c, b->bud->lnum, LPROPS_NC, LPROPS_NC, + LPROPS_NC, LPROPS_NC)) + return 0; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, b->bud->lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) && + can_ignore_failure_callback(c, FR_LPT_CORRUPTED)) + err = 0; + goto out; + } + + dirty = lp->dirty; + if (b->bud->start == 0 && (lp->free != c->leb_size || lp->dirty != 0)) { + /* + * The LEB was added to the journal with a starting offset of + * zero which means the LEB must have been empty. The LEB + * property values should be @lp->free == @c->leb_size and + * @lp->dirty == 0, but that is not the case. The reason is that + * the LEB had been garbage collected before it became the bud, + * and there was no commit in between. The garbage collector + * resets the free and dirty space without recording it + * anywhere except lprops, so if there was no commit then + * lprops does not have that information. + * + * We do not need to adjust free space because the scan has told + * us the exact value which is recorded in the replay entry as + * @b->free. + * + * However we do need to subtract from the dirty space the + * amount of space that the garbage collector reclaimed, which + * is the whole LEB minus the amount of space that was free. + */ + dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum, + lp->free, lp->dirty); + dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", b->bud->lnum, + lp->free, lp->dirty); + dirty -= c->leb_size - lp->free; + /* + * If the replay order was perfect the dirty space would now be + * zero. The order is not perfect because the journal heads + * race with each other. This is not a problem but is does mean + * that the dirty space may temporarily exceed c->leb_size + * during the replay. + */ + if (dirty != 0) + dbg_mnt("LEB %d lp: %d free %d dirty replay: %d free %d dirty", + b->bud->lnum, lp->free, lp->dirty, b->free, + b->dirty); + } + if (!test_lpt_valid_callback(c, b->bud->lnum, lp->free, lp->dirty, + b->free, dirty + b->dirty)) + goto out; + + lp = ubifs_change_lp(c, lp, b->free, dirty + b->dirty, + lp->flags | LPROPS_TAKEN, 0); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + /* Make sure the journal head points to the latest bud */ + err = ubifs_wbuf_seek_nolock(&c->jheads[b->bud->jhead].wbuf, + b->bud->lnum, c->leb_size - b->free); + +out: + ubifs_release_lprops(c); + return err; +} + +/** + * set_buds_lprops - set free and dirty space for all replayed buds. + * @c: UBIFS file-system description object + * + * This function sets LEB properties for all replayed buds. Returns zero in + * case of success and a negative error code in case of failure. + */ +static int set_buds_lprops(struct ubifs_info *c) +{ + struct bud_entry *b; + int err; + + list_for_each_entry(b, &c->replay_buds, list) { + err = set_bud_lprops(c, b); + if (err) + return err; + } + + return 0; +} + +/** + * trun_remove_range - apply a replay entry for a truncation to the TNC. + * @c: UBIFS file-system description object + * @r: replay entry of truncation + */ +static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r) +{ + unsigned min_blk, max_blk; + union ubifs_key min_key, max_key; + ino_t ino; + + min_blk = r->new_size / UBIFS_BLOCK_SIZE; + if (r->new_size & (UBIFS_BLOCK_SIZE - 1)) + min_blk += 1; + + max_blk = r->old_size / UBIFS_BLOCK_SIZE; + if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0) + max_blk -= 1; + + ino = key_inum(c, &r->key); + + data_key_init(c, &min_key, ino, min_blk); + data_key_init(c, &max_key, ino, max_blk); + + return ubifs_tnc_remove_range(c, &min_key, &max_key); +} + +/** + * inode_still_linked - check whether inode in question will be re-linked. + * @c: UBIFS file-system description object + * @rino: replay entry to test + * + * O_TMPFILE files can be re-linked, this means link count goes from 0 to 1. + * This case needs special care, otherwise all references to the inode will + * be removed upon the first replay entry of an inode with link count 0 + * is found. + */ +static bool inode_still_linked(struct ubifs_info *c, struct replay_entry *rino) +{ + struct replay_entry *r; + + ubifs_assert(c, rino->deletion); + ubifs_assert(c, key_type(c, &rino->key) == UBIFS_INO_KEY); + + /* + * Find the most recent entry for the inode behind @rino and check + * whether it is a deletion. + */ + list_for_each_entry_reverse(r, &c->replay_list, list) { + ubifs_assert(c, r->sqnum >= rino->sqnum); + if (key_inum(c, &r->key) == key_inum(c, &rino->key) && + key_type(c, &r->key) == UBIFS_INO_KEY) + return r->deletion == 0; + + } + + ubifs_assert(c, 0); + return false; +} + +/** + * apply_replay_entry - apply a replay entry to the TNC. + * @c: UBIFS file-system description object + * @r: replay entry to apply + * + * Apply a replay entry to the TNC. + */ +static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r) +{ + int err; + + dbg_mntk(&r->key, "LEB %d:%d len %d deletion %d sqnum %llu key ", + r->lnum, r->offs, r->len, r->deletion, r->sqnum); + + if (is_hash_key(c, &r->key)) { + if (r->deletion) + err = ubifs_tnc_remove_nm(c, &r->key, &r->nm); + else + err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs, + r->len, r->hash, &r->nm); + } else { + if (r->deletion) + switch (key_type(c, &r->key)) { + case UBIFS_INO_KEY: + { + ino_t inum = key_inum(c, &r->key); + + if (inode_still_linked(c, r)) { + err = 0; + break; + } + + err = ubifs_tnc_remove_ino(c, inum); + break; + } + case UBIFS_TRUN_KEY: + err = trun_remove_range(c, r); + break; + default: + err = ubifs_tnc_remove(c, &r->key); + break; + } + else + err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs, + r->len, r->hash); + if (err) + return err; + + if (c->need_recovery) + err = ubifs_recover_size_accum(c, &r->key, r->deletion, + r->new_size); + } + + return err; +} + +/** + * replay_entries_cmp - compare 2 replay entries. + * @priv: UBIFS file-system description object + * @a: first replay entry + * @b: second replay entry + * + * This is a comparios function for 'list_sort()' which compares 2 replay + * entries @a and @b by comparing their sequence number. Returns %1 if @a has + * greater sequence number and %-1 otherwise. + */ +static int replay_entries_cmp(void *priv, const struct list_head *a, + const struct list_head *b) +{ + struct ubifs_info *c = priv; + struct replay_entry *ra, *rb; + + cond_resched(); + if (a == b) + return 0; + + ra = list_entry(a, struct replay_entry, list); + rb = list_entry(b, struct replay_entry, list); + ubifs_assert(c, ra->sqnum != rb->sqnum); + if (ra->sqnum > rb->sqnum) + return 1; + return -1; +} + +/** + * apply_replay_list - apply the replay list to the TNC. + * @c: UBIFS file-system description object + * + * Apply all entries in the replay list to the TNC. Returns zero in case of + * success and a negative error code in case of failure. + */ +static int apply_replay_list(struct ubifs_info *c) +{ + struct replay_entry *r; + int err; + + list_sort(c, &c->replay_list, &replay_entries_cmp); + + list_for_each_entry(r, &c->replay_list, list) { + cond_resched(); + + err = apply_replay_entry(c, r); + if (err) + return err; + } + + return 0; +} + +/** + * destroy_replay_list - destroy the replay. + * @c: UBIFS file-system description object + * + * Destroy the replay list. + */ +static void destroy_replay_list(struct ubifs_info *c) +{ + struct replay_entry *r, *tmp; + + list_for_each_entry_safe(r, tmp, &c->replay_list, list) { + if (is_hash_key(c, &r->key)) + kfree(fname_name(&r->nm)); + list_del(&r->list); + kfree(r); + } +} + +/** + * insert_node - insert a node to the replay list + * @c: UBIFS file-system description object + * @lnum: node logical eraseblock number + * @offs: node offset + * @len: node length + * @key: node key + * @sqnum: sequence number + * @deletion: non-zero if this is a deletion + * @used: number of bytes in use in a LEB + * @old_size: truncation old size + * @new_size: truncation new size + * + * This function inserts a scanned non-direntry node to the replay list. The + * replay list contains @struct replay_entry elements, and we sort this list in + * sequence number order before applying it. The replay list is applied at the + * very end of the replay process. Since the list is sorted in sequence number + * order, the older modifications are applied first. This function returns zero + * in case of success and a negative error code in case of failure. + */ +static int insert_node(struct ubifs_info *c, int lnum, int offs, int len, + const u8 *hash, union ubifs_key *key, + unsigned long long sqnum, int deletion, int *used, + loff_t old_size, loff_t new_size) +{ + struct replay_entry *r; + + dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs); + + if (key_inum(c, key) >= c->highest_inum) + c->highest_inum = key_inum(c, key); + + r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL); + if (!r) + return -ENOMEM; + + if (!deletion) + *used += ALIGN(len, 8); + r->lnum = lnum; + r->offs = offs; + r->len = len; + ubifs_copy_hash(c, hash, r->hash); + r->deletion = !!deletion; + r->sqnum = sqnum; + key_copy(c, key, &r->key); + r->old_size = old_size; + r->new_size = new_size; + + list_add_tail(&r->list, &c->replay_list); + return 0; +} + +/** + * insert_dent - insert a directory entry node into the replay list. + * @c: UBIFS file-system description object + * @lnum: node logical eraseblock number + * @offs: node offset + * @len: node length + * @key: node key + * @name: directory entry name + * @nlen: directory entry name length + * @sqnum: sequence number + * @deletion: non-zero if this is a deletion + * @used: number of bytes in use in a LEB + * + * This function inserts a scanned directory entry node or an extended + * attribute entry to the replay list. Returns zero in case of success and a + * negative error code in case of failure. + */ +static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len, + const u8 *hash, union ubifs_key *key, + const char *name, int nlen, unsigned long long sqnum, + int deletion, int *used) +{ + struct replay_entry *r; + char *nbuf; + + dbg_mntk(key, "add LEB %d:%d, key ", lnum, offs); + if (key_inum(c, key) >= c->highest_inum) + c->highest_inum = key_inum(c, key); + + r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL); + if (!r) + return -ENOMEM; + + nbuf = kmalloc(nlen + 1, GFP_KERNEL); + if (!nbuf) { + kfree(r); + return -ENOMEM; + } + + if (!deletion) + *used += ALIGN(len, 8); + r->lnum = lnum; + r->offs = offs; + r->len = len; + ubifs_copy_hash(c, hash, r->hash); + r->deletion = !!deletion; + r->sqnum = sqnum; + key_copy(c, key, &r->key); + fname_len(&r->nm) = nlen; + memcpy(nbuf, name, nlen); + nbuf[nlen] = '\0'; + fname_name(&r->nm) = nbuf; + + list_add_tail(&r->list, &c->replay_list); + return 0; +} + +/** + * ubifs_validate_entry - validate directory or extended attribute entry node. + * @c: UBIFS file-system description object + * @dent: the node to validate + * + * This function validates directory or extended attribute entry node @dent. + * Returns zero if the node is all right and a %-EINVAL if not. + */ +int ubifs_validate_entry(struct ubifs_info *c, + const struct ubifs_dent_node *dent) +{ + int key_type = key_type_flash(c, dent->key); + int nlen = le16_to_cpu(dent->nlen); + + if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 || + dent->type >= UBIFS_ITYPES_CNT || + nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 || + (key_type == UBIFS_XENT_KEY && + strnlen((const char *)dent->name, nlen) != nlen) || + le64_to_cpu(dent->inum) > MAX_INUM) { + ubifs_err(c, "bad %s node", key_type == UBIFS_DENT_KEY ? + "directory entry" : "extended attribute entry"); + return -EINVAL; + } + + if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) { + ubifs_err(c, "bad key type %d", key_type); + return -EINVAL; + } + + return 0; +} + +/** + * is_last_bud - check if the bud is the last in the journal head. + * @c: UBIFS file-system description object + * @bud: bud description object + * + * This function checks if bud @bud is the last bud in its journal head. This + * information is then used by 'replay_bud()' to decide whether the bud can + * have corruptions or not. Indeed, only last buds can be corrupted by power + * cuts. Returns %1 if this is the last bud, and %0 if not. + */ +static int is_last_bud(struct ubifs_info *c, struct ubifs_bud *bud) +{ + struct ubifs_jhead *jh = &c->jheads[bud->jhead]; + struct ubifs_bud *next; + uint32_t data; + int err; + + if (list_is_last(&bud->list, &jh->buds_list)) + return 1; + + /* + * The following is a quirk to make sure we work correctly with UBIFS + * images used with older UBIFS. + * + * Normally, the last bud will be the last in the journal head's list + * of bud. However, there is one exception if the UBIFS image belongs + * to older UBIFS. This is fairly unlikely: one would need to use old + * UBIFS, then have a power cut exactly at the right point, and then + * try to mount this image with new UBIFS. + * + * The exception is: it is possible to have 2 buds A and B, A goes + * before B, and B is the last, bud B is contains no data, and bud A is + * corrupted at the end. The reason is that in older versions when the + * journal code switched the next bud (from A to B), it first added a + * log reference node for the new bud (B), and only after this it + * synchronized the write-buffer of current bud (A). But later this was + * changed and UBIFS started to always synchronize the write-buffer of + * the bud (A) before writing the log reference for the new bud (B). + * + * But because older UBIFS always synchronized A's write-buffer before + * writing to B, we can recognize this exceptional situation but + * checking the contents of bud B - if it is empty, then A can be + * treated as the last and we can recover it. + * + * TODO: remove this piece of code in a couple of years (today it is + * 16.05.2011). + */ + next = list_entry(bud->list.next, struct ubifs_bud, list); + if (!list_is_last(&next->list, &jh->buds_list)) + return 0; + + err = ubifs_leb_read(c, next->lnum, (char *)&data, next->start, 4, 1); + if (err) + return 0; + + return data == 0xFFFFFFFF; +} + +/** + * authenticate_sleb - authenticate one scan LEB + * @c: UBIFS file-system description object + * @sleb: the scan LEB to authenticate + * @log_hash: + * @is_last: if true, this is the last LEB + * + * This function iterates over the buds of a single LEB authenticating all buds + * with the authentication nodes on this LEB. Authentication nodes are written + * after some buds and contain a HMAC covering the authentication node itself + * and the buds between the last authentication node and the current + * authentication node. It can happen that the last buds cannot be authenticated + * because a powercut happened when some nodes were written but not the + * corresponding authentication node. This function returns the number of nodes + * that could be authenticated or a negative error code. + */ +static int authenticate_sleb(struct ubifs_info *c, struct ubifs_scan_leb *sleb, + __unused struct shash_desc *log_hash, + __unused int is_last) +{ + if (!ubifs_authenticated(c)) + return sleb->nodes_cnt; + + // To be implemented + return -EINVAL; +} + +/** + * replay_bud - replay a bud logical eraseblock. + * @c: UBIFS file-system description object + * @b: bud entry which describes the bud + * + * This function replays bud @bud, recovers it if needed, and adds all nodes + * from this bud to the replay list. Returns zero in case of success and a + * negative error code in case of failure. + */ +static int replay_bud(struct ubifs_info *c, struct bud_entry *b) +{ + int is_last = is_last_bud(c, b->bud); + int err = 0, used = 0, lnum = b->bud->lnum, offs = b->bud->start; + int n_nodes, n = 0; + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + + dbg_mnt("replay bud LEB %d, head %d, offs %d, is_last %d", + lnum, b->bud->jhead, offs, is_last); + + if (c->need_recovery && is_last) + /* + * Recover only last LEBs in the journal heads, because power + * cuts may cause corruptions only in these LEBs, because only + * these LEBs could possibly be written to at the power cut + * time. + */ + sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, b->bud->jhead); + else + sleb = ubifs_scan(c, lnum, offs, c->sbuf, 0); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + + n_nodes = authenticate_sleb(c, sleb, b->bud->log_hash, is_last); + if (n_nodes < 0) { + err = n_nodes; + goto out; + } + + ubifs_shash_copy_state(c, b->bud->log_hash, + c->jheads[b->bud->jhead].log_hash); + + /* + * The bud does not have to start from offset zero - the beginning of + * the 'lnum' LEB may contain previously committed data. One of the + * things we have to do in replay is to correctly update lprops with + * newer information about this LEB. + * + * At this point lprops thinks that this LEB has 'c->leb_size - offs' + * bytes of free space because it only contain information about + * committed data. + * + * But we know that real amount of free space is 'c->leb_size - + * sleb->endpt', and the space in the 'lnum' LEB between 'offs' and + * 'sleb->endpt' is used by bud data. We have to correctly calculate + * how much of these data are dirty and update lprops with this + * information. + * + * The dirt in that LEB region is comprised of padding nodes, deletion + * nodes, truncation nodes and nodes which are obsoleted by subsequent + * nodes in this LEB. So instead of calculating clean space, we + * calculate used space ('used' variable). + */ + + list_for_each_entry(snod, &sleb->nodes, list) { + u8 hash[UBIFS_HASH_ARR_SZ]; + int deletion = 0; + + cond_resched(); + + if (snod->sqnum >= SQNUM_WATERMARK) { + ubifs_err(c, "file system's life ended"); + goto out_dump; + } + + ubifs_node_calc_hash(c, snod->node, hash); + + if (snod->sqnum > c->max_sqnum) + c->max_sqnum = snod->sqnum; + + switch (snod->type) { + case UBIFS_INO_NODE: + { + struct ubifs_ino_node *ino = snod->node; + loff_t new_size = le64_to_cpu(ino->size); + + if (le32_to_cpu(ino->nlink) == 0) + deletion = 1; + err = insert_node(c, lnum, snod->offs, snod->len, hash, + &snod->key, snod->sqnum, deletion, + &used, 0, new_size); + break; + } + case UBIFS_DATA_NODE: + { + struct ubifs_data_node *dn = snod->node; + loff_t new_size = le32_to_cpu(dn->size) + + key_block(c, &snod->key) * + UBIFS_BLOCK_SIZE; + + err = insert_node(c, lnum, snod->offs, snod->len, hash, + &snod->key, snod->sqnum, deletion, + &used, 0, new_size); + break; + } + case UBIFS_DENT_NODE: + case UBIFS_XENT_NODE: + { + struct ubifs_dent_node *dent = snod->node; + + err = ubifs_validate_entry(c, dent); + if (err) + goto out_dump; + + err = insert_dent(c, lnum, snod->offs, snod->len, hash, + &snod->key, (const char *)dent->name, + le16_to_cpu(dent->nlen), snod->sqnum, + !le64_to_cpu(dent->inum), &used); + break; + } + case UBIFS_TRUN_NODE: + { + struct ubifs_trun_node *trun = snod->node; + loff_t old_size = le64_to_cpu(trun->old_size); + loff_t new_size = le64_to_cpu(trun->new_size); + union ubifs_key key; + + /* Validate truncation node */ + if (old_size < 0 || old_size > c->max_inode_sz || + new_size < 0 || new_size > c->max_inode_sz || + old_size <= new_size) { + ubifs_err(c, "bad truncation node"); + goto out_dump; + } + + /* + * Create a fake truncation key just to use the same + * functions which expect nodes to have keys. + */ + trun_key_init(c, &key, le32_to_cpu(trun->inum)); + err = insert_node(c, lnum, snod->offs, snod->len, hash, + &key, snod->sqnum, 1, &used, + old_size, new_size); + break; + } + case UBIFS_AUTH_NODE: + break; + default: + ubifs_err(c, "unexpected node type %d in bud LEB %d:%d", + snod->type, lnum, snod->offs); + err = -EINVAL; + goto out_dump; + } + if (err) + goto out; + + n++; + if (n == n_nodes) + break; + } + + ubifs_assert(c, ubifs_search_bud(c, lnum)); + ubifs_assert(c, sleb->endpt - offs >= used); + ubifs_assert(c, sleb->endpt % c->min_io_size == 0); + + b->dirty = sleb->endpt - offs - used; + b->free = c->leb_size - sleb->endpt; + dbg_mnt("bud LEB %d replied: dirty %d, free %d", + lnum, b->dirty, b->free); + +out: + ubifs_scan_destroy(sleb); + return err; + +out_dump: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "bad node is at LEB %d:%d", lnum, snod->offs); + ubifs_dump_node(c, snod->node, c->leb_size - snod->offs); + ubifs_scan_destroy(sleb); + return -EINVAL; +} + +/** + * replay_buds - replay all buds. + * @c: UBIFS file-system description object + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int replay_buds(struct ubifs_info *c) +{ + struct bud_entry *b, *tmp_b; + int err; + unsigned long long prev_sqnum = 0; + + list_for_each_entry_safe(b, tmp_b, &c->replay_buds, list) { + err = replay_bud(c, b); + if (err) { + if (test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED) && + handle_failure_callback(c, FR_H_BUD_CORRUPTED, b->bud)) { + /* Set %FR_LPT_INCORRECT for lpt status. */ + set_lpt_invalid_callback(c, FR_LPT_INCORRECT); + /* Skip replaying the bud LEB. */ + list_del(&b->list); + kfree(b); + continue; + } + return err; + } + + ubifs_assert(c, b->sqnum > prev_sqnum); + prev_sqnum = b->sqnum; + } + + return 0; +} + +/** + * destroy_bud_list - destroy the list of buds to replay. + * @c: UBIFS file-system description object + */ +static void destroy_bud_list(struct ubifs_info *c) +{ + struct bud_entry *b; + + while (!list_empty(&c->replay_buds)) { + b = list_entry(c->replay_buds.next, struct bud_entry, list); + list_del(&b->list); + kfree(b); + } +} + +/** + * add_replay_bud - add a bud to the list of buds to replay. + * @c: UBIFS file-system description object + * @lnum: bud logical eraseblock number to replay + * @offs: bud start offset + * @jhead: journal head to which this bud belongs + * @sqnum: reference node sequence number + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead, + unsigned long long sqnum) +{ + struct ubifs_bud *bud; + struct bud_entry *b; + int err; + + dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead); + + bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL); + if (!bud) + return -ENOMEM; + + b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL); + if (!b) { + err = -ENOMEM; + goto out; + } + + bud->lnum = lnum; + bud->start = offs; + bud->jhead = jhead; + bud->log_hash = ubifs_hash_get_desc(c); + if (IS_ERR(bud->log_hash)) { + err = PTR_ERR(bud->log_hash); + goto out; + } + + ubifs_shash_copy_state(c, c->log_hash, bud->log_hash); + + ubifs_add_bud(c, bud); + + b->bud = bud; + b->sqnum = sqnum; + list_add_tail(&b->list, &c->replay_buds); + + return 0; +out: + kfree(bud); + kfree(b); + + return err; +} + +/** + * validate_ref - validate a reference node. + * @c: UBIFS file-system description object + * @ref: the reference node to validate + * + * This function returns %1 if a bud reference already exists for the LEB. %0 is + * returned if the reference node is new, otherwise %-EINVAL is returned if + * validation failed. + */ +static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref) +{ + struct ubifs_bud *bud; + int lnum = le32_to_cpu(ref->lnum); + unsigned int offs = le32_to_cpu(ref->offs); + unsigned int jhead = le32_to_cpu(ref->jhead); + + /* + * ref->offs may point to the end of LEB when the journal head points + * to the end of LEB and we write reference node for it during commit. + * So this is why we require 'offs > c->leb_size'. + */ + if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt || + lnum < c->main_first || offs > c->leb_size || + offs & (c->min_io_size - 1)) + return -EINVAL; + + /* Make sure we have not already looked at this bud */ + bud = ubifs_search_bud(c, lnum); + if (bud) { + if (bud->jhead == jhead && bud->start <= offs) + return 1; + ubifs_err(c, "bud at LEB %d:%d was already referred", lnum, offs); + return -EINVAL; + } + + return 0; +} + +/** + * replay_log_leb - replay a log logical eraseblock. + * @c: UBIFS file-system description object + * @lnum: log logical eraseblock to replay + * @offs: offset to start replaying from + * @sbuf: scan buffer + * + * This function replays a log LEB and returns zero in case of success, %1 if + * this is the last LEB in the log, and a negative error code in case of + * failure. + */ +static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf) +{ + int err; + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + const struct ubifs_cs_node *node; + + dbg_mnt("replay log LEB %d:%d", lnum, offs); + sleb = ubifs_scan(c, lnum, offs, sbuf, c->need_recovery); + if (IS_ERR(sleb)) { + if (PTR_ERR(sleb) != -EUCLEAN || !c->need_recovery) + return PTR_ERR(sleb); + clear_failure_reason_callback(c); + /* + * Note, the below function will recover this log LEB only if + * it is the last, because unclean reboots can possibly corrupt + * only the tail of the log. + */ + sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + } + + if (sleb->nodes_cnt == 0) { + err = 1; + goto out; + } + + node = sleb->buf; + snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list); + if (c->cs_sqnum == 0) { + /* + * This is the first log LEB we are looking at, make sure that + * the first node is a commit start node. Also record its + * sequence number so that UBIFS can determine where the log + * ends, because all nodes which were have higher sequence + * numbers. + */ + if (snod->type != UBIFS_CS_NODE) { + ubifs_err(c, "first log node at LEB %d:%d is not CS node", + lnum, offs); + goto out_dump; + } + if (le64_to_cpu(node->cmt_no) != c->cmt_no) { + ubifs_err(c, "first CS node at LEB %d:%d has wrong commit number %llu expected %llu", + lnum, offs, + (unsigned long long)le64_to_cpu(node->cmt_no), + c->cmt_no); + goto out_dump; + } + + c->cs_sqnum = le64_to_cpu(node->ch.sqnum); + dbg_mnt("commit start sqnum %llu", c->cs_sqnum); + + err = ubifs_shash_init(c, c->log_hash); + if (err) + goto out; + + err = ubifs_shash_update(c, c->log_hash, node, UBIFS_CS_NODE_SZ); + if (err < 0) + goto out; + } + + if (snod->sqnum < c->cs_sqnum) { + /* + * This means that we reached end of log and now + * look to the older log data, which was already + * committed but the eraseblock was not erased (UBIFS + * only un-maps it). So this basically means we have to + * exit with "end of log" code. + */ + err = 1; + goto out; + } + + /* Make sure the first node sits at offset zero of the LEB */ + if (snod->offs != 0) { + ubifs_err(c, "first node is not at zero offset"); + goto out_dump; + } + + list_for_each_entry(snod, &sleb->nodes, list) { + cond_resched(); + + if (snod->sqnum >= SQNUM_WATERMARK) { + ubifs_err(c, "file system's life ended"); + goto out_dump; + } + + if (snod->sqnum < c->cs_sqnum) { + ubifs_err(c, "bad sqnum %llu, commit sqnum %llu", + snod->sqnum, c->cs_sqnum); + goto out_dump; + } + + if (snod->sqnum > c->max_sqnum) + c->max_sqnum = snod->sqnum; + + switch (snod->type) { + case UBIFS_REF_NODE: { + const struct ubifs_ref_node *ref = snod->node; + + err = validate_ref(c, ref); + if (err == 1) + break; /* Already have this bud */ + if (err) + goto out_dump; + + err = ubifs_shash_update(c, c->log_hash, ref, + UBIFS_REF_NODE_SZ); + if (err) + goto out; + + err = add_replay_bud(c, le32_to_cpu(ref->lnum), + le32_to_cpu(ref->offs), + le32_to_cpu(ref->jhead), + snod->sqnum); + if (err) + goto out; + + break; + } + case UBIFS_CS_NODE: + /* Make sure it sits at the beginning of LEB */ + if (snod->offs != 0) { + ubifs_err(c, "unexpected node in log"); + goto out_dump; + } + break; + default: + ubifs_err(c, "unexpected node in log"); + goto out_dump; + } + } + + if (sleb->endpt || c->lhead_offs >= c->leb_size) { + c->lhead_lnum = lnum; + c->lhead_offs = sleb->endpt; + } + + err = !sleb->endpt; +out: + ubifs_scan_destroy(sleb); + return err; + +out_dump: + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "log error detected while replaying the log at LEB %d:%d", + lnum, offs + snod->offs); + ubifs_dump_node(c, snod->node, c->leb_size - snod->offs); + ubifs_scan_destroy(sleb); + return -EINVAL; +} + +/** + * take_ihead - update the status of the index head in lprops to 'taken'. + * @c: UBIFS file-system description object + * + * This function returns the amount of free space in the index head LEB or a + * negative error code. + */ +int take_ihead(struct ubifs_info *c) +{ + const struct ubifs_lprops *lp; + int err, free; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) && + can_ignore_failure_callback(c, FR_LPT_CORRUPTED)) + err = 0; + goto out; + } + + free = lp->free; + + if (!test_lpt_valid_callback(c, c->ihead_lnum, LPROPS_NC, LPROPS_NC, + LPROPS_NC, LPROPS_NC)) { + err = free; + goto out; + } + + lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC, + lp->flags | LPROPS_TAKEN, 0); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + err = free; +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_replay_journal - replay journal. + * @c: UBIFS file-system description object + * + * This function scans the journal, replays and cleans it up. It makes sure all + * memory data structures related to uncommitted journal are built (dirty TNC + * tree, tree of buds, modified lprops, etc). + */ +int ubifs_replay_journal(struct ubifs_info *c) +{ + int err, lnum, free; + + BUILD_BUG_ON(UBIFS_TRUN_KEY > 5); + + /* Update the status of the index head in lprops to 'taken' */ + free = take_ihead(c); + if (free < 0) + return free; /* Error code */ + + if (c->program_type != FSCK_PROGRAM_TYPE) { + /* + * Skip index head checking for fsck, it is hard to check it + * caused by possible corrupted/incorrect lpt, tnc updating + * will report error code if index tree is really corrupted. + */ + if (c->ihead_offs != c->leb_size - free) { + ubifs_err(c, "bad index head LEB %d:%d", c->ihead_lnum, + c->ihead_offs); + return -EINVAL; + } + } + + dbg_mnt("start replaying the journal"); + c->replaying = 1; + lnum = c->ltail_lnum = c->lhead_lnum; + + do { + err = replay_log_leb(c, lnum, 0, c->sbuf); + if (err == 1) { + if (lnum != c->lhead_lnum) + /* We hit the end of the log */ + break; + + /* + * The head of the log must always start with the + * "commit start" node on a properly formatted UBIFS. + * But we found no nodes at all, which means that + * something went wrong and we cannot proceed mounting + * the file-system. + */ + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "no UBIFS nodes found at the log head LEB %d:%d, possibly corrupted", + lnum, 0); + err = -EINVAL; + } + if (err) + goto out; + lnum = ubifs_next_log_lnum(c, lnum); + } while (lnum != c->ltail_lnum); + + err = replay_buds(c); + if (err) + goto out; + + err = apply_replay_list(c); + if (err) + goto out; + + err = set_buds_lprops(c); + if (err) + goto out; + + /* + * UBIFS budgeting calculations use @c->bi.uncommitted_idx variable + * to roughly estimate index growth. Things like @c->bi.min_idx_lebs + * depend on it. This means we have to initialize it to make sure + * budgeting works properly. + */ + c->bi.uncommitted_idx = atomic_long_read(&c->dirty_zn_cnt); + c->bi.uncommitted_idx *= c->max_idx_node_sz; + + ubifs_assert(c, c->bud_bytes <= c->max_bud_bytes || c->need_recovery); + dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, highest_inum %lu", + c->lhead_lnum, c->lhead_offs, c->max_sqnum, + (unsigned long)c->highest_inum); +out: + destroy_replay_list(c); + destroy_bud_list(c); + c->replaying = 0; + return err; +} diff --git a/ubifs-utils/libubifs/sb.c b/ubifs-utils/libubifs/sb.c new file mode 100644 index 0000000..2147280 --- /dev/null +++ b/ubifs-utils/libubifs/sb.c @@ -0,0 +1,512 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements UBIFS superblock. The superblock is stored at the first + * LEB of the volume and is never changed by UBIFS. Only user-space tools may + * change it. The superblock node mostly contains geometry information. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/* Default number of LEB numbers in LPT's save table */ +#define DEFAULT_LSAVE_CNT 256 + +/** + * validate_sb - validate superblock node. + * @c: UBIFS file-system description object + * @sup: superblock node + * + * This function validates superblock node @sup. Since most of data was read + * from the superblock and stored in @c, the function validates fields in @c + * instead. Returns zero in case of success and %-EINVAL in case of validation + * failure. + */ +static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup) +{ + long long max_bytes; + int err = 1, min_leb_cnt; + + if (!c->key_hash) { + err = 2; + goto failed; + } + + if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) { + err = 3; + goto failed; + } + + if (le32_to_cpu(sup->min_io_size) != c->min_io_size) { + ubifs_err(c, "min. I/O unit mismatch: %d in superblock, %d real", + le32_to_cpu(sup->min_io_size), c->min_io_size); + goto failed; + } + + if (le32_to_cpu(sup->leb_size) != c->leb_size) { + ubifs_err(c, "LEB size mismatch: %d in superblock, %d real", + le32_to_cpu(sup->leb_size), c->leb_size); + goto failed; + } + + if (c->log_lebs < UBIFS_MIN_LOG_LEBS || + c->lpt_lebs < UBIFS_MIN_LPT_LEBS || + c->orph_lebs < UBIFS_MIN_ORPH_LEBS || + c->main_lebs < UBIFS_MIN_MAIN_LEBS) { + err = 4; + goto failed; + } + + /* + * Calculate minimum allowed amount of main area LEBs. This is very + * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we + * have just read from the superblock. + */ + min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs; + min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6; + + if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.rsvd_lebs) { + ubifs_err(c, "bad LEB count: %d in superblock, %d on UBI volume, %d minimum required", + c->leb_cnt, c->vi.rsvd_lebs, min_leb_cnt); + goto failed; + } + + if (c->max_leb_cnt < c->leb_cnt) { + ubifs_err(c, "max. LEB count %d less than LEB count %d", + c->max_leb_cnt, c->leb_cnt); + goto failed; + } + + if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) { + ubifs_err(c, "too few main LEBs count %d, must be at least %d", + c->main_lebs, UBIFS_MIN_MAIN_LEBS); + goto failed; + } + + max_bytes = (long long)c->leb_size * UBIFS_MIN_BUD_LEBS; + if (c->max_bud_bytes < max_bytes) { + ubifs_err(c, "too small journal (%lld bytes), must be at least %lld bytes", + c->max_bud_bytes, max_bytes); + goto failed; + } + + max_bytes = (long long)c->leb_size * c->main_lebs; + if (c->max_bud_bytes > max_bytes) { + ubifs_err(c, "too large journal size (%lld bytes), only %lld bytes available in the main area", + c->max_bud_bytes, max_bytes); + goto failed; + } + + if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 || + c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) { + err = 9; + goto failed; + } + + if (c->fanout < UBIFS_MIN_FANOUT || + ubifs_idx_node_sz(c, c->fanout) > c->leb_size) { + err = 10; + goto failed; + } + + if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT && + c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - + c->log_lebs - c->lpt_lebs - c->orph_lebs)) { + err = 11; + goto failed; + } + + if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs + + c->orph_lebs + c->main_lebs != c->leb_cnt) { + err = 12; + goto failed; + } + + if (c->default_compr >= UBIFS_COMPR_TYPES_CNT) { + err = 13; + goto failed; + } + + if (c->rp_size < 0 || max_bytes < c->rp_size) { + err = 14; + goto failed; + } + + if (le32_to_cpu(sup->time_gran) > 1000000000 || + le32_to_cpu(sup->time_gran) < 1) { + err = 15; + goto failed; + } + + if (!c->double_hash && c->fmt_version >= 5) { + err = 16; + goto failed; + } + + if (c->encrypted && c->fmt_version < 5) { + err = 17; + goto failed; + } + + return 0; + +failed: + ubifs_err(c, "bad superblock, error %d", err); + ubifs_dump_node(c, sup, ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size)); + return -EINVAL; +} + +/** + * ubifs_read_sb_node - read superblock node. + * @c: UBIFS file-system description object + * + * This function returns a pointer to the superblock node or a negative error + * code. Note, the user of this function is responsible of kfree()'ing the + * returned superblock buffer. + */ +static struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c) +{ + struct ubifs_sb_node *sup; + int err; + + sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS); + if (!sup) + return ERR_PTR(-ENOMEM); + + err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ, + UBIFS_SB_LNUM, 0); + if (err) { + kfree(sup); + return ERR_PTR(err); + } + + return sup; +} + +static int authenticate_sb_node(__unused struct ubifs_info *c, + const struct ubifs_sb_node *sup) +{ + unsigned int sup_flags = le32_to_cpu(sup->flags); + int authenticated = !!(sup_flags & UBIFS_FLG_AUTHENTICATION); + + if (authenticated) { + // To be implemented + ubifs_err(c, "not support authentication"); + return -EOPNOTSUPP; + } + + return 0; +} + +/** + * ubifs_write_sb_node - write superblock node. + * @c: UBIFS file-system description object + * @sup: superblock node read with 'ubifs_read_sb_node()' + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup) +{ + int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); + int err; + + err = ubifs_prepare_node_hmac(c, sup, UBIFS_SB_NODE_SZ, + offsetof(struct ubifs_sb_node, hmac), 1); + if (err) + return err; + + return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len); +} + +/** + * ubifs_read_superblock - read superblock. + * @c: UBIFS file-system description object + * + * This function finds, reads and checks the superblock. If an empty UBI volume + * is being mounted, this function creates default superblock. Returns zero in + * case of success, and a negative error code in case of failure. + */ +int ubifs_read_superblock(struct ubifs_info *c) +{ + int err, sup_flags; + struct ubifs_sb_node *sup; + + sup = ubifs_read_sb_node(c); + if (IS_ERR(sup)) + return PTR_ERR(sup); + + c->sup_node = sup; + + c->fmt_version = le32_to_cpu(sup->fmt_version); + c->ro_compat_version = le32_to_cpu(sup->ro_compat_version); + + /* + * The software supports all previous versions but not future versions, + * due to the unavailability of time-travelling equipment. + */ + if (c->fmt_version > UBIFS_FORMAT_VERSION) { + ubifs_assert(c, !c->ro_media || c->ro_mount); + if (!c->ro_mount || + c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) { + ubifs_err(c, "on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d", + c->fmt_version, c->ro_compat_version, + UBIFS_FORMAT_VERSION, + UBIFS_RO_COMPAT_VERSION); + if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) { + ubifs_msg(c, "only R/O mounting is possible"); + err = -EROFS; + } else + err = -EINVAL; + goto out; + } + } + + if (c->fmt_version < 3) { + ubifs_err(c, "on-flash format version %d is not supported", + c->fmt_version); + err = -EINVAL; + goto out; + } + + switch (sup->key_hash) { + case UBIFS_KEY_HASH_R5: + c->key_hash = key_r5_hash; + c->key_hash_type = UBIFS_KEY_HASH_R5; + break; + + case UBIFS_KEY_HASH_TEST: + c->key_hash = key_test_hash; + c->key_hash_type = UBIFS_KEY_HASH_TEST; + break; + } + + c->key_fmt = sup->key_fmt; + + switch (c->key_fmt) { + case UBIFS_SIMPLE_KEY_FMT: + c->key_len = UBIFS_SK_LEN; + break; + default: + ubifs_err(c, "unsupported key format"); + err = -EINVAL; + goto out; + } + + c->leb_cnt = le32_to_cpu(sup->leb_cnt); + c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt); + c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes); + c->log_lebs = le32_to_cpu(sup->log_lebs); + c->lpt_lebs = le32_to_cpu(sup->lpt_lebs); + c->orph_lebs = le32_to_cpu(sup->orph_lebs); + c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT; + c->fanout = le32_to_cpu(sup->fanout); + c->lsave_cnt = le32_to_cpu(sup->lsave_cnt); + c->rp_size = le64_to_cpu(sup->rp_size); + sup_flags = le32_to_cpu(sup->flags); + c->default_compr = le16_to_cpu(sup->default_compr); + + c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT); + c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP); + c->double_hash = !!(sup_flags & UBIFS_FLG_DOUBLE_HASH); + c->encrypted = !!(sup_flags & UBIFS_FLG_ENCRYPTION); + + err = authenticate_sb_node(c, sup); + if (err) + goto out; + + if ((sup_flags & ~UBIFS_FLG_MASK) != 0) { + ubifs_err(c, "Unknown feature flags found: %#x", + sup_flags & ~UBIFS_FLG_MASK); + err = -EINVAL; + goto out; + } + + /* Automatically increase file system size to the maximum size */ + if (c->leb_cnt < c->vi.rsvd_lebs && c->leb_cnt < c->max_leb_cnt) { + int old_leb_cnt = c->leb_cnt; + + c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.rsvd_lebs); + sup->leb_cnt = cpu_to_le32(c->leb_cnt); + + c->superblock_need_write = 1; + + dbg_mnt("Auto resizing from %d LEBs to %d LEBs", + old_leb_cnt, c->leb_cnt); + } + + c->log_bytes = (long long)c->log_lebs * c->leb_size; + c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1; + c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs; + c->lpt_last = c->lpt_first + c->lpt_lebs - 1; + c->orph_first = c->lpt_last + 1; + c->orph_last = c->orph_first + c->orph_lebs - 1; + c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS; + c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs; + c->main_first = c->leb_cnt - c->main_lebs; + + err = validate_sb(c, sup); +out: + if (err) + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + return err; +} + +/** + * fixup_leb - fixup/unmap an LEB containing free space. + * @c: UBIFS file-system description object + * @lnum: the LEB number to fix up + * @len: number of used bytes in LEB (starting at offset 0) + * + * This function reads the contents of the given LEB number @lnum, then fixes + * it up, so that empty min. I/O units in the end of LEB are actually erased on + * flash (rather than being just all-0xff real data). If the LEB is completely + * empty, it is simply unmapped. + */ +static int fixup_leb(struct ubifs_info *c, int lnum, int len) +{ + int err; + + ubifs_assert(c, len >= 0); + ubifs_assert(c, len % c->min_io_size == 0); + ubifs_assert(c, len < c->leb_size); + + if (len == 0) { + dbg_mnt("unmap empty LEB %d", lnum); + return ubifs_leb_unmap(c, lnum); + } + + dbg_mnt("fixup LEB %d, data len %d", lnum, len); + err = ubifs_leb_read(c, lnum, c->sbuf, 0, len, 1); + if (err && err != -EBADMSG) + return err; + + return ubifs_leb_change(c, lnum, c->sbuf, len); +} + +/** + * fixup_free_space - find & remap all LEBs containing free space. + * @c: UBIFS file-system description object + * + * This function walks through all LEBs in the filesystem and fiexes up those + * containing free/empty space. + */ +static int fixup_free_space(struct ubifs_info *c) +{ + int lnum, err = 0; + struct ubifs_lprops *lprops; + + ubifs_get_lprops(c); + + /* Fixup LEBs in the master area */ + for (lnum = UBIFS_MST_LNUM; lnum < UBIFS_LOG_LNUM; lnum++) { + err = fixup_leb(c, lnum, c->mst_offs + c->mst_node_alsz); + if (err) + goto out; + } + + /* Unmap unused log LEBs */ + lnum = ubifs_next_log_lnum(c, c->lhead_lnum); + while (lnum != c->ltail_lnum) { + err = fixup_leb(c, lnum, 0); + if (err) + goto out; + lnum = ubifs_next_log_lnum(c, lnum); + } + + /* + * Fixup the log head which contains the only a CS node at the + * beginning. + */ + err = fixup_leb(c, c->lhead_lnum, + ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size)); + if (err) + goto out; + + /* Fixup LEBs in the LPT area */ + for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) { + int free = c->ltab[lnum - c->lpt_first].free; + + if (free > 0) { + err = fixup_leb(c, lnum, c->leb_size - free); + if (err) + goto out; + } + } + + /* Unmap LEBs in the orphans area */ + for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { + err = fixup_leb(c, lnum, 0); + if (err) + goto out; + } + + /* Fixup LEBs in the main area */ + for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) { + lprops = ubifs_lpt_lookup(c, lnum); + if (IS_ERR(lprops)) { + err = PTR_ERR(lprops); + goto out; + } + + if (lprops->free > 0) { + err = fixup_leb(c, lnum, c->leb_size - lprops->free); + if (err) + goto out; + } + } + +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_fixup_free_space - find & fix all LEBs with free space. + * @c: UBIFS file-system description object + * + * This function fixes up LEBs containing free space on first mount, if the + * appropriate flag was set when the FS was created. Each LEB with one or more + * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure + * the free space is actually erased. E.g., this is necessary for some NAND + * chips, since the free space may have been programmed like real "0xff" data + * (generating a non-0xff ECC), causing future writes to the not-really-erased + * NAND pages to behave badly. After the space is fixed up, the superblock flag + * is cleared, so that this is skipped for all future mounts. + */ +int ubifs_fixup_free_space(struct ubifs_info *c) +{ + int err; + struct ubifs_sb_node *sup = c->sup_node; + + ubifs_assert(c, c->space_fixup); + ubifs_assert(c, !c->ro_mount); + + ubifs_msg(c, "start fixing up free space"); + + err = fixup_free_space(c); + if (err) + return err; + + /* Free-space fixup is no longer required */ + c->space_fixup = 0; + sup->flags &= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP); + + c->superblock_need_write = 1; + + ubifs_msg(c, "free space fixup complete"); + return err; +} diff --git a/ubifs-utils/libubifs/scan.c b/ubifs-utils/libubifs/scan.c new file mode 100644 index 0000000..e9581a6 --- /dev/null +++ b/ubifs-utils/libubifs/scan.c @@ -0,0 +1,372 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the scan which is a general-purpose function for + * determining what nodes are in an eraseblock. The scan is used to replay the + * journal, to do garbage collection. for the TNC in-the-gaps method, and by + * debugging functions. + */ + +#include "linux_err.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" + +/** + * scan_padding_bytes - scan for padding bytes. + * @buf: buffer to scan + * @len: length of buffer + * + * This function returns the number of padding bytes on success and + * %SCANNED_GARBAGE on failure. + */ +static int scan_padding_bytes(void *buf, int len) +{ + int pad_len = 0, max_pad_len = min_t(int, UBIFS_PAD_NODE_SZ, len); + uint8_t *p = buf; + + dbg_scan("not a node"); + + while (pad_len < max_pad_len && *p++ == UBIFS_PADDING_BYTE) + pad_len += 1; + + if (!pad_len || (pad_len & 7)) + return SCANNED_GARBAGE; + + dbg_scan("%d padding bytes", pad_len); + + return pad_len; +} + +/** + * ubifs_scan_a_node - scan for a node or padding. + * @c: UBIFS file-system description object + * @buf: buffer to scan + * @len: length of buffer + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * @quiet: print no messages + * + * This function returns a scanning code to indicate what was scanned. + */ +int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum, + int offs, int quiet) +{ + struct ubifs_ch *ch = buf; + uint32_t magic; + + magic = le32_to_cpu(ch->magic); + + if (magic == 0xFFFFFFFF) { + dbg_scan("hit empty space at LEB %d:%d", lnum, offs); + return SCANNED_EMPTY_SPACE; + } + + if (magic != UBIFS_NODE_MAGIC) + return scan_padding_bytes(buf, len); + + if (len < UBIFS_CH_SZ) + return SCANNED_GARBAGE; + + dbg_scan("scanning %s at LEB %d:%d", + dbg_ntype(ch->node_type), lnum, offs); + + if (ubifs_check_node(c, buf, len, lnum, offs, quiet, 1)) + return SCANNED_A_CORRUPT_NODE; + + if (ch->node_type == UBIFS_PAD_NODE) { + struct ubifs_pad_node *pad = buf; + int pad_len = le32_to_cpu(pad->pad_len); + int node_len = le32_to_cpu(ch->len); + + /* Validate the padding node */ + if (pad_len < 0 || + offs + node_len + pad_len > c->leb_size) { + if (!quiet) { + ubifs_err(c, "bad pad node at LEB %d:%d", + lnum, offs); + ubifs_dump_node(c, pad, len); + } + return SCANNED_A_BAD_PAD_NODE; + } + + /* Make the node pads to 8-byte boundary */ + if ((node_len + pad_len) & 7) { + if (!quiet) + ubifs_err(c, "bad padding length %d - %d", + offs, offs + node_len + pad_len); + return SCANNED_A_BAD_PAD_NODE; + } + + dbg_scan("%d bytes padded at LEB %d:%d, offset now %d", pad_len, + lnum, offs, ALIGN(offs + node_len + pad_len, 8)); + + return node_len + pad_len; + } + + return SCANNED_A_NODE; +} + +/** + * ubifs_start_scan - create LEB scanning information at start of scan. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number + * @offs: offset to start at (usually zero) + * @sbuf: scan buffer (must be c->leb_size) + * + * This function returns the scanned information on success and a negative error + * code on failure. + */ +struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf) +{ + struct ubifs_scan_leb *sleb; + int err; + + dbg_scan("scan LEB %d:%d", lnum, offs); + + sleb = kzalloc(sizeof(struct ubifs_scan_leb), GFP_NOFS); + if (!sleb) + return ERR_PTR(-ENOMEM); + + sleb->lnum = lnum; + INIT_LIST_HEAD(&sleb->nodes); + sleb->buf = sbuf; + + err = ubifs_leb_read(c, lnum, sbuf + offs, offs, c->leb_size - offs, 0); + if (err && err != -EBADMSG) { + ubifs_err(c, "cannot read %d bytes from LEB %d:%d, error %d", + c->leb_size - offs, lnum, offs, err); + kfree(sleb); + return ERR_PTR(err); + } + + /* + * Note, we ignore integrity errors (EBASMSG) because all the nodes are + * protected by CRC checksums. + */ + return sleb; +} + +/** + * ubifs_end_scan - update LEB scanning information at end of scan. + * @c: UBIFS file-system description object + * @sleb: scanning information + * @lnum: logical eraseblock number + * @offs: offset to start at (usually zero) + */ +void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + int lnum, int offs) +{ + dbg_scan("stop scanning LEB %d at offset %d", lnum, offs); + ubifs_assert(c, offs % c->min_io_size == 0); + + sleb->endpt = ALIGN(offs, c->min_io_size); +} + +/** + * ubifs_add_snod - add a scanned node to LEB scanning information. + * @c: UBIFS file-system description object + * @sleb: scanning information + * @buf: buffer containing node + * @offs: offset of node on flash + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + void *buf, int offs) +{ + struct ubifs_ch *ch = buf; + struct ubifs_ino_node *ino = buf; + struct ubifs_scan_node *snod; + + snod = kmalloc(sizeof(struct ubifs_scan_node), GFP_NOFS); + if (!snod) + return -ENOMEM; + + snod->sqnum = le64_to_cpu(ch->sqnum); + snod->type = ch->node_type; + snod->offs = offs; + snod->len = le32_to_cpu(ch->len); + snod->node = buf; + + switch (ch->node_type) { + case UBIFS_INO_NODE: + case UBIFS_DENT_NODE: + case UBIFS_XENT_NODE: + case UBIFS_DATA_NODE: + /* + * The key is in the same place in all keyed + * nodes. + */ + key_read(c, &ino->key, &snod->key); + break; + default: + invalid_key_init(c, &snod->key); + break; + } + list_add_tail(&snod->list, &sleb->nodes); + sleb->nodes_cnt += 1; + return 0; +} + +/** + * ubifs_scanned_corruption - print information after UBIFS scanned corruption. + * @c: UBIFS file-system description object + * @lnum: LEB number of corruption + * @offs: offset of corruption + * @buf: buffer containing corruption + */ +void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs, + void *buf) +{ + int len; + + ubifs_err(c, "corruption at LEB %d:%d", lnum, offs); + len = c->leb_size - offs; + if (len > 8192) + len = 8192; + ubifs_err(c, "first %d bytes from LEB %d:%d", len, lnum, offs); + print_hex_dump("", DUMP_PREFIX_OFFSET, 32, 4, buf, len, 1); +} + +/** + * ubifs_scan - scan a logical eraseblock. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number + * @offs: offset to start at (usually zero) + * @sbuf: scan buffer (must be of @c->leb_size bytes in size) + * @quiet: print no messages + * + * This function scans LEB number @lnum and returns complete information about + * its contents. Returns the scanned information in case of success and, + * %-EUCLEAN if the LEB neads recovery, and other negative error codes in case + * of failure. + * + * If @quiet is non-zero, this function does not print large and scary + * error messages and flash dumps in case of errors. + */ +struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf, int quiet) +{ + void *buf = sbuf + offs; + int err, len = c->leb_size - offs; + struct ubifs_scan_leb *sleb; + + sleb = ubifs_start_scan(c, lnum, offs, sbuf); + if (IS_ERR(sleb)) + return sleb; + + while (len >= 8) { + struct ubifs_ch *ch = buf; + int node_len, ret; + + dbg_scan("look at LEB %d:%d (%d bytes left)", + lnum, offs, len); + + cond_resched(); + + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet); + if (ret > 0) { + /* Padding bytes or a valid padding node */ + offs += ret; + buf += ret; + len -= ret; + continue; + } + + if (ret == SCANNED_EMPTY_SPACE) + /* Empty space is checked later */ + break; + + switch (ret) { + case SCANNED_GARBAGE: + ubifs_err(c, "garbage"); + goto corrupted; + case SCANNED_A_NODE: + break; + case SCANNED_A_CORRUPT_NODE: + case SCANNED_A_BAD_PAD_NODE: + ubifs_err(c, "bad node"); + goto corrupted; + default: + ubifs_err(c, "unknown"); + err = -EINVAL; + goto error; + } + + err = ubifs_add_snod(c, sleb, buf, offs); + if (err) + goto error; + + node_len = ALIGN(le32_to_cpu(ch->len), 8); + offs += node_len; + buf += node_len; + len -= node_len; + } + + if (offs % c->min_io_size) { + if (!quiet) + ubifs_err(c, "empty space starts at non-aligned offset %d", + offs); + goto corrupted; + } + + ubifs_end_scan(c, sleb, lnum, offs); + + for (; len > 4; offs += 4, buf = buf + 4, len -= 4) + if (*(uint32_t *)buf != 0xffffffff) + break; + for (; len; offs++, buf++, len--) + if (*(uint8_t *)buf != 0xff) { + if (!quiet) + ubifs_err(c, "corrupt empty space at LEB %d:%d", + lnum, offs); + goto corrupted; + } + + return sleb; + +corrupted: + if (!quiet) { + ubifs_scanned_corruption(c, lnum, offs, buf); + ubifs_err(c, "LEB %d scanning failed", lnum); + } + err = -EUCLEAN; + ubifs_scan_destroy(sleb); + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + return ERR_PTR(err); + +error: + ubifs_err(c, "LEB %d scanning failed, error %d", lnum, err); + ubifs_scan_destroy(sleb); + return ERR_PTR(err); +} + +/** + * ubifs_scan_destroy - destroy LEB scanning information. + * @sleb: scanning information to free + */ +void ubifs_scan_destroy(struct ubifs_scan_leb *sleb) +{ + struct ubifs_scan_node *node; + struct list_head *head; + + head = &sleb->nodes; + while (!list_empty(head)) { + node = list_entry(head->next, struct ubifs_scan_node, list); + list_del(&node->list); + kfree(node); + } + kfree(sleb); +} diff --git a/ubifs-utils/libubifs/super.c b/ubifs-utils/libubifs/super.c new file mode 100644 index 0000000..559623f --- /dev/null +++ b/ubifs-utils/libubifs/super.c @@ -0,0 +1,702 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements UBIFS initialization and VFS superblock operations. Some + * initialization stuff which is rather large and complex is placed at + * corresponding subsystems, but most of it is here. + */ + +#include <stdio.h> +#include <unistd.h> +#include <sys/stat.h> +#include <sys/types.h> + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +atomic_long_t ubifs_clean_zn_cnt; +static const int default_debug_level = WARN_LEVEL; + +/** + * open_ubi - open the libubi. + * @c: the UBIFS file-system description object + * @node: name of the UBI volume character device to fetch information about + * + * This function opens libubi, and initialize device & volume information + * according to @node. Returns %0 in case of success and %-1 in case of failure. + */ +int open_ubi(struct ubifs_info *c, const char *node) +{ + struct stat st; + + if (stat(node, &st)) + return -1; + + if (!S_ISCHR(st.st_mode)) { + errno = ENODEV; + return -1; + } + + c->libubi = libubi_open(); + if (!c->libubi) + return -1; + if (ubi_get_vol_info(c->libubi, node, &c->vi)) + goto out_err; + if (ubi_get_dev_info1(c->libubi, c->vi.dev_num, &c->di)) + goto out_err; + + return 0; + +out_err: + close_ubi(c); + return -1; +} + +void close_ubi(struct ubifs_info *c) +{ + if (c->libubi) { + libubi_close(c->libubi); + c->libubi = NULL; + } +} + +/** + * open_target - open the output target. + * @c: the UBIFS file-system description object + * + * Open the output target. The target can be an UBI volume + * or a file. + * + * Returns %0 in case of success and a negative error code in case of failure. + */ +int open_target(struct ubifs_info *c) +{ + if (c->libubi) { + c->dev_fd = open(c->dev_name, O_RDWR | O_EXCL); + + if (c->dev_fd == -1) { + ubifs_err(c, "cannot open the UBI volume. %s", + strerror(errno)); + return -errno; + } + if (ubi_set_property(c->dev_fd, UBI_VOL_PROP_DIRECT_WRITE, 1)) { + close(c->dev_fd); + ubifs_err(c, "ubi_set_property(set direct_write) failed. %s", + strerror(errno)); + return -errno; + } + } else { + c->dev_fd = open(c->dev_name, O_CREAT | O_RDWR | O_TRUNC, + S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH); + if (c->dev_fd == -1) { + ubifs_err(c, "cannot create output file. %s", + strerror(errno)); + return -errno; + } + } + return 0; +} + +/** + * close_target - close the output target. + * @c: the UBIFS file-system description object + * + * Close the output target. If the target was an UBI + * volume, also close libubi. + * + * Returns %0 in case of success and a negative error code in case of failure. + */ +int close_target(struct ubifs_info *c) +{ + if (c->dev_fd >= 0) { + if (c->libubi && ubi_set_property(c->dev_fd, UBI_VOL_PROP_DIRECT_WRITE, 0)) { + ubifs_err(c, "ubi_set_property(clear direct_write) failed. %s", + strerror(errno)); + return -errno; + } + if (close(c->dev_fd) == -1) { + ubifs_err(c, "cannot close the target. %s", + strerror(errno)); + return -errno; + } + } + return 0; +} + +/** + * ubifs_open_volume - open UBI volume. + * @c: the UBIFS file-system description object + * @volume_name: the UBI volume name + * + * Open ubi volume. This function is implemented by open_ubi + open_target. + * + * Returns %0 in case of success and a negative error code in case of failure. + */ +int ubifs_open_volume(struct ubifs_info *c, const char *volume_name) +{ + int err; + + err = open_ubi(c, volume_name); + if (err) { + ubifs_err(c, "cannot open libubi. %s", strerror(errno)); + return err; + } + + err = open_target(c); + if (err) + close_ubi(c); + + return err; +} + +/** + * ubifs_close_volume - close UBI volume. + * @c: the UBIFS file-system description object + * + * Close ubi volume. This function is implemented by close_target + close_ubi. + * + * Returns %0 in case of success and a negative error code in case of failure. + */ +int ubifs_close_volume(struct ubifs_info *c) +{ + int err; + + err = close_target(c); + if (err) + return err; + + close_ubi(c); + + return 0; +} + +/** + * check_volume_empty - check if the UBI volume is empty. + * @c: the UBIFS file-system description object + * + * This function checks if the UBI volume is empty by looking if its LEBs are + * mapped or not. + * + * Returns %0 in case of success, %1 is the volume is not empty, + * and a negative error code in case of failure. + */ +int check_volume_empty(struct ubifs_info *c) +{ + int lnum, err; + + for (lnum = 0; lnum < c->vi.rsvd_lebs; lnum++) { + err = ubi_is_mapped(c->dev_fd, lnum); + if (err < 0) + return err; + if (err == 1) + return 1; + } + return 0; +} + +void init_ubifs_info(struct ubifs_info *c, int program_type) +{ + spin_lock_init(&c->cnt_lock); + spin_lock_init(&c->cs_lock); + spin_lock_init(&c->buds_lock); + spin_lock_init(&c->space_lock); + spin_lock_init(&c->orphan_lock); + init_rwsem(&c->commit_sem); + mutex_init(&c->lp_mutex); + mutex_init(&c->tnc_mutex); + mutex_init(&c->log_mutex); + c->buds = RB_ROOT; + c->old_idx = RB_ROOT; + c->size_tree = RB_ROOT; + c->orph_tree = RB_ROOT; + INIT_LIST_HEAD(&c->idx_gc); + INIT_LIST_HEAD(&c->replay_list); + INIT_LIST_HEAD(&c->replay_buds); + INIT_LIST_HEAD(&c->uncat_list); + INIT_LIST_HEAD(&c->empty_list); + INIT_LIST_HEAD(&c->freeable_list); + INIT_LIST_HEAD(&c->frdi_idx_list); + INIT_LIST_HEAD(&c->unclean_leb_list); + INIT_LIST_HEAD(&c->old_buds); + INIT_LIST_HEAD(&c->orph_list); + INIT_LIST_HEAD(&c->orph_new); + c->no_chk_data_crc = 1; + + c->highest_inum = UBIFS_FIRST_INO; + c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM; + + c->program_type = program_type; + switch (c->program_type) { + case MKFS_PROGRAM_TYPE: + c->program_name = MKFS_PROGRAM_NAME; + break; + case FSCK_PROGRAM_TYPE: + c->program_name = FSCK_PROGRAM_NAME; + /* Always check crc for data node. */ + c->no_chk_data_crc = 0; + break; + default: + assert(0); + break; + } + c->dev_fd = -1; + c->debug_level = default_debug_level; +} + +/** + * init_constants_early - initialize UBIFS constants. + * @c: UBIFS file-system description object + * + * This function initialize UBIFS constants which do not need the superblock to + * be read. It also checks that the UBI volume satisfies basic UBIFS + * requirements. Returns zero in case of success and a negative error code in + * case of failure. + */ +int init_constants_early(struct ubifs_info *c) +{ +#define NOR_MAX_WRITESZ 64 + if (c->vi.corrupted) { + ubifs_warn(c, "UBI volume is corrupted - read-only mode"); + c->ro_media = 1; + } + + if (c->vi.type == UBI_STATIC_VOLUME) { + ubifs_msg(c, "static UBI volume - read-only mode"); + c->ro_media = 1; + } + + c->max_inode_sz = key_max_inode_size(c); + c->leb_cnt = c->vi.rsvd_lebs; + c->leb_size = c->vi.leb_size; + c->half_leb_size = c->leb_size / 2; + c->min_io_size = c->di.min_io_size; + c->min_io_shift = fls(c->min_io_size) - 1; + if (c->min_io_size == 1) + /* + * Different from linux kernel, the max write size of nor flash + * is not exposed in sysfs, just reset @c->max_write_size. + */ + c->max_write_size = NOR_MAX_WRITESZ; + else + c->max_write_size = c->di.min_io_size; + c->max_write_shift = fls(c->max_write_size) - 1; + + if (c->leb_size < UBIFS_MIN_LEB_SZ) { + ubifs_err(c, "too small LEBs (%d bytes), min. is %d bytes", + c->leb_size, UBIFS_MIN_LEB_SZ); + return -EINVAL; + } + + if (c->leb_cnt < UBIFS_MIN_LEB_CNT) { + ubifs_err(c, "too few LEBs (%d), min. is %d", + c->leb_cnt, UBIFS_MIN_LEB_CNT); + return -EINVAL; + } + + if (!is_power_of_2(c->min_io_size)) { + ubifs_err(c, "bad min. I/O size %d", c->min_io_size); + return -EINVAL; + } + + /* + * Maximum write size has to be greater or equivalent to min. I/O + * size, and be multiple of min. I/O size. + */ + if (c->max_write_size < c->min_io_size || + c->max_write_size % c->min_io_size || + !is_power_of_2(c->max_write_size)) { + ubifs_err(c, "bad write buffer size %d for %d min. I/O unit", + c->max_write_size, c->min_io_size); + return -EINVAL; + } + + /* + * UBIFS aligns all node to 8-byte boundary, so to make function in + * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is + * less than 8. + */ + if (c->min_io_size < 8) { + c->min_io_size = 8; + c->min_io_shift = 3; + if (c->max_write_size < c->min_io_size) { + c->max_write_size = c->min_io_size; + c->max_write_shift = c->min_io_shift; + } + } + + c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size); + c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size); + + /* + * Initialize node length ranges which are mostly needed for node + * length validation. + */ + c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ; + c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ; + c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ; + c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ; + c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ; + c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ; + c->ranges[UBIFS_AUTH_NODE].min_len = UBIFS_AUTH_NODE_SZ; + c->ranges[UBIFS_AUTH_NODE].max_len = UBIFS_AUTH_NODE_SZ + + UBIFS_MAX_HMAC_LEN; + c->ranges[UBIFS_SIG_NODE].min_len = UBIFS_SIG_NODE_SZ; + c->ranges[UBIFS_SIG_NODE].max_len = c->leb_size - UBIFS_SB_NODE_SZ; + + c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ; + c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ; + c->ranges[UBIFS_ORPH_NODE].min_len = + UBIFS_ORPH_NODE_SZ + sizeof(__le64); + c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size; + c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ; + c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ; + c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ; + c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ; + c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ; + c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ; + /* + * Minimum indexing node size is amended later when superblock is + * read and the key length is known. + */ + c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ; + /* + * Maximum indexing node size is amended later when superblock is + * read and the fanout is known. + */ + c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX; + + /* + * Initialize dead and dark LEB space watermarks. See gc.c for comments + * about these values. + */ + c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size); + c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size); + + /* + * Calculate how many bytes would be wasted at the end of LEB if it was + * fully filled with data nodes of maximum size. This is used in + * calculations when reporting free space. + */ + c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ; + + /* Log is ready, preserve one LEB for commits. */ + c->min_log_bytes = c->leb_size; + + return 0; +} + +/** + * bud_wbuf_callback - bud LEB write-buffer synchronization call-back. + * @c: UBIFS file-system description object + * @lnum: LEB the write-buffer was synchronized to + * @free: how many free bytes left in this LEB + * @pad: how many bytes were padded + * + * This is a callback function which is called by the I/O unit when the + * write-buffer is synchronized. We need this to correctly maintain space + * accounting in bud logical eraseblocks. This function returns zero in case of + * success and a negative error code in case of failure. + * + * This function actually belongs to the journal, but we keep it here because + * we want to keep it static. + */ +static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad) +{ + return ubifs_update_one_lp(c, lnum, free, pad, 0, 0); +} + +/* + * init_constants_sb - initialize UBIFS constants. + * @c: UBIFS file-system description object + * + * This is a helper function which initializes various UBIFS constants after + * the superblock has been read. It also checks various UBIFS parameters and + * makes sure they are all right. Returns zero in case of success and a + * negative error code in case of failure. + */ +int init_constants_sb(struct ubifs_info *c) +{ + int tmp, err; + long long tmp64; + + c->main_bytes = (long long)c->main_lebs * c->leb_size; + c->max_znode_sz = sizeof(struct ubifs_znode) + + c->fanout * sizeof(struct ubifs_zbranch); + + tmp = ubifs_idx_node_sz(c, 1); + c->ranges[UBIFS_IDX_NODE].min_len = tmp; + c->min_idx_node_sz = ALIGN(tmp, 8); + + tmp = ubifs_idx_node_sz(c, c->fanout); + c->ranges[UBIFS_IDX_NODE].max_len = tmp; + c->max_idx_node_sz = ALIGN(tmp, 8); + + /* Make sure LEB size is large enough to fit full commit */ + tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt; + tmp = ALIGN(tmp, c->min_io_size); + if (tmp > c->leb_size) { + ubifs_err(c, "too small LEB size %d, at least %d needed", + c->leb_size, tmp); + return -EINVAL; + } + + /* + * Make sure that the log is large enough to fit reference nodes for + * all buds plus one reserved LEB. + */ + tmp64 = c->max_bud_bytes + c->leb_size - 1; + c->max_bud_cnt = div_u64(tmp64, c->leb_size); + tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1); + tmp /= c->leb_size; + tmp += 1; + if (c->log_lebs < tmp) { + ubifs_err(c, "too small log %d LEBs, required min. %d LEBs", + c->log_lebs, tmp); + return -EINVAL; + } + + /* + * When budgeting we assume worst-case scenarios when the pages are not + * be compressed and direntries are of the maximum size. + * + * Note, data, which may be stored in inodes is budgeted separately, so + * it is not included into 'c->bi.inode_budget'. + */ + c->bi.page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE; + c->bi.inode_budget = UBIFS_INO_NODE_SZ; + c->bi.dent_budget = UBIFS_MAX_DENT_NODE_SZ; + + /* + * When the amount of flash space used by buds becomes + * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit. + * The writers are unblocked when the commit is finished. To avoid + * writers to be blocked UBIFS initiates background commit in advance, + * when number of bud bytes becomes above the limit defined below. + */ + c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4; + + /* + * Ensure minimum journal size. All the bytes in the journal heads are + * considered to be used, when calculating the current journal usage. + * Consequently, if the journal is too small, UBIFS will treat it as + * always full. + */ + tmp64 = (long long)(c->jhead_cnt + 1) * c->leb_size + 1; + if (c->bg_bud_bytes < tmp64) + c->bg_bud_bytes = tmp64; + if (c->max_bud_bytes < tmp64 + c->leb_size) + c->max_bud_bytes = tmp64 + c->leb_size; + + err = ubifs_calc_lpt_geom(c); + if (err) + return err; + + /* Initialize effective LEB size used in budgeting calculations */ + c->idx_leb_size = c->leb_size - c->max_idx_node_sz; + return 0; +} + +/* + * init_constants_master - initialize UBIFS constants. + * @c: UBIFS file-system description object + * + * This is a helper function which initializes various UBIFS constants after + * the master node has been read. It also checks various UBIFS parameters and + * makes sure they are all right. + */ +void init_constants_master(struct ubifs_info *c) +{ + c->bi.min_idx_lebs = ubifs_calc_min_idx_lebs(c); +} + +/** + * take_gc_lnum - reserve GC LEB. + * @c: UBIFS file-system description object + * + * This function ensures that the LEB reserved for garbage collection is marked + * as "taken" in lprops. We also have to set free space to LEB size and dirty + * space to zero, because lprops may contain out-of-date information if the + * file-system was un-mounted before it has been committed. This function + * returns zero in case of success and a negative error code in case of + * failure. + */ +int take_gc_lnum(struct ubifs_info *c) +{ + int err; + + if (c->gc_lnum == -1) { + ubifs_err(c, "no LEB for GC"); + return -EINVAL; + } + + /* And we have to tell lprops that this LEB is taken */ + err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0, + LPROPS_TAKEN, 0, 0); + return err; +} + +/** + * alloc_wbufs - allocate write-buffers. + * @c: UBIFS file-system description object + * + * This helper function allocates and initializes UBIFS write-buffers. Returns + * zero in case of success and %-ENOMEM in case of failure. + */ +int alloc_wbufs(struct ubifs_info *c) +{ + int i, err; + + c->jheads = kcalloc(c->jhead_cnt, sizeof(struct ubifs_jhead), + GFP_KERNEL); + if (!c->jheads) + return -ENOMEM; + + /* Initialize journal heads */ + for (i = 0; i < c->jhead_cnt; i++) { + INIT_LIST_HEAD(&c->jheads[i].buds_list); + err = ubifs_wbuf_init(c, &c->jheads[i].wbuf); + if (err) + goto out_wbuf; + + c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback; + c->jheads[i].wbuf.jhead = i; + c->jheads[i].grouped = 1; + c->jheads[i].log_hash = ubifs_hash_get_desc(c); + if (IS_ERR(c->jheads[i].log_hash)) { + err = PTR_ERR(c->jheads[i].log_hash); + goto out_log_hash; + } + } + + /* + * Garbage Collector head does not need to be synchronized by timer. + * Also GC head nodes are not grouped. + */ + c->jheads[GCHD].grouped = 0; + + return 0; + +out_log_hash: + kfree(c->jheads[i].wbuf.buf); + kfree(c->jheads[i].wbuf.inodes); + +out_wbuf: + while (i--) { + kfree(c->jheads[i].wbuf.buf); + kfree(c->jheads[i].wbuf.inodes); + kfree(c->jheads[i].log_hash); + } + kfree(c->jheads); + c->jheads = NULL; + + return err; +} + +/** + * free_wbufs - free write-buffers. + * @c: UBIFS file-system description object + */ +void free_wbufs(struct ubifs_info *c) +{ + int i; + + if (c->jheads) { + for (i = 0; i < c->jhead_cnt; i++) { + kfree(c->jheads[i].wbuf.buf); + kfree(c->jheads[i].wbuf.inodes); + kfree(c->jheads[i].log_hash); + } + kfree(c->jheads); + c->jheads = NULL; + } +} + +/** + * free_orphans - free orphans. + * @c: UBIFS file-system description object + */ +void free_orphans(struct ubifs_info *c) +{ + struct ubifs_orphan *orph; + + while (c->orph_dnext) { + orph = c->orph_dnext; + c->orph_dnext = orph->dnext; + list_del(&orph->list); + kfree(orph); + } + + while (!list_empty(&c->orph_list)) { + orph = list_entry(c->orph_list.next, struct ubifs_orphan, list); + list_del(&orph->list); + kfree(orph); + ubifs_err(c, "orphan list not empty at unmount"); + } + + vfree(c->orph_buf); + c->orph_buf = NULL; +} + +/** + * free_buds - free per-bud objects. + * @c: UBIFS file-system description object + * @delete_from_list: whether to delete the bud from list + */ +void free_buds(struct ubifs_info *c, bool delete_from_list) +{ + struct ubifs_bud *bud, *n; + + rbtree_postorder_for_each_entry_safe(bud, n, &c->buds, rb) { + if (delete_from_list) + list_del(&bud->list); + kfree(bud->log_hash); + kfree(bud); + } + + c->buds = RB_ROOT; +} + +/** + * destroy_journal - destroy journal data structures. + * @c: UBIFS file-system description object + * + * This function destroys journal data structures including those that may have + * been created by recovery functions. + */ +void destroy_journal(struct ubifs_info *c) +{ + while (!list_empty(&c->unclean_leb_list)) { + struct ubifs_unclean_leb *ucleb; + + ucleb = list_entry(c->unclean_leb_list.next, + struct ubifs_unclean_leb, list); + list_del(&ucleb->list); + kfree(ucleb); + } + while (!list_empty(&c->old_buds)) { + struct ubifs_bud *bud; + + bud = list_entry(c->old_buds.next, struct ubifs_bud, list); + list_del(&bud->list); + kfree(bud->log_hash); + kfree(bud); + } + ubifs_destroy_idx_gc(c); + ubifs_destroy_size_tree(c); + ubifs_tnc_close(c); + free_buds(c, false); +} diff --git a/ubifs-utils/libubifs/tnc.c b/ubifs-utils/libubifs/tnc.c new file mode 100644 index 0000000..9277062 --- /dev/null +++ b/ubifs-utils/libubifs/tnc.c @@ -0,0 +1,3070 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements TNC (Tree Node Cache) which caches indexing nodes of + * the UBIFS B-tree. + * + * At the moment the locking rules of the TNC tree are quite simple and + * straightforward. We just have a mutex and lock it when we traverse the + * tree. If a znode is not in memory, we read it from flash while still having + * the mutex locked. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "crc32.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +static int try_read_node(const struct ubifs_info *c, void *buf, int type, + struct ubifs_zbranch *zbr); +static int fallible_read_node(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_zbranch *zbr, void *node); + +/* + * Returned codes of 'matches_name()' and 'fallible_matches_name()' functions. + * @NAME_LESS: name corresponding to the first argument is less than second + * @NAME_MATCHES: names match + * @NAME_GREATER: name corresponding to the second argument is greater than + * first + * @NOT_ON_MEDIA: node referred by zbranch does not exist on the media + * + * These constants were introduce to improve readability. + */ +enum { + NAME_LESS = 0, + NAME_MATCHES = 1, + NAME_GREATER = 2, + NOT_ON_MEDIA = 3, +}; + +static void do_insert_old_idx(struct ubifs_info *c, + struct ubifs_old_idx *old_idx) +{ + struct ubifs_old_idx *o; + struct rb_node **p, *parent = NULL; + + p = &c->old_idx.rb_node; + while (*p) { + parent = *p; + o = rb_entry(parent, struct ubifs_old_idx, rb); + if (old_idx->lnum < o->lnum) + p = &(*p)->rb_left; + else if (old_idx->lnum > o->lnum) + p = &(*p)->rb_right; + else if (old_idx->offs < o->offs) + p = &(*p)->rb_left; + else if (old_idx->offs > o->offs) + p = &(*p)->rb_right; + else { + ubifs_err(c, "old idx added twice!"); + kfree(old_idx); + return; + } + } + rb_link_node(&old_idx->rb, parent, p); + rb_insert_color(&old_idx->rb, &c->old_idx); +} + +/** + * insert_old_idx - record an index node obsoleted since the last commit start. + * @c: UBIFS file-system description object + * @lnum: LEB number of obsoleted index node + * @offs: offset of obsoleted index node + * + * Returns %0 on success, and a negative error code on failure. + * + * For recovery, there must always be a complete intact version of the index on + * flash at all times. That is called the "old index". It is the index as at the + * time of the last successful commit. Many of the index nodes in the old index + * may be dirty, but they must not be erased until the next successful commit + * (at which point that index becomes the old index). + * + * That means that the garbage collection and the in-the-gaps method of + * committing must be able to determine if an index node is in the old index. + * Most of the old index nodes can be found by looking up the TNC using the + * 'lookup_znode()' function. However, some of the old index nodes may have + * been deleted from the current index or may have been changed so much that + * they cannot be easily found. In those cases, an entry is added to an RB-tree. + * That is what this function does. The RB-tree is ordered by LEB number and + * offset because they uniquely identify the old index node. + */ +static int insert_old_idx(struct ubifs_info *c, int lnum, int offs) +{ + struct ubifs_old_idx *old_idx; + + old_idx = kmalloc(sizeof(struct ubifs_old_idx), GFP_NOFS); + if (unlikely(!old_idx)) + return -ENOMEM; + old_idx->lnum = lnum; + old_idx->offs = offs; + do_insert_old_idx(c, old_idx); + + return 0; +} + +/** + * insert_old_idx_znode - record a znode obsoleted since last commit start. + * @c: UBIFS file-system description object + * @znode: znode of obsoleted index node + * + * Returns %0 on success, and a negative error code on failure. + */ +int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode) +{ + if (znode->parent) { + struct ubifs_zbranch *zbr; + + zbr = &znode->parent->zbranch[znode->iip]; + if (zbr->len) + return insert_old_idx(c, zbr->lnum, zbr->offs); + } else + if (c->zroot.len) + return insert_old_idx(c, c->zroot.lnum, + c->zroot.offs); + return 0; +} + +/** + * ins_clr_old_idx_znode - record a znode obsoleted since last commit start. + * @c: UBIFS file-system description object + * @znode: znode of obsoleted index node + * + * Returns %0 on success, and a negative error code on failure. + */ +static int ins_clr_old_idx_znode(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + int err; + + if (znode->parent) { + struct ubifs_zbranch *zbr; + + zbr = &znode->parent->zbranch[znode->iip]; + if (zbr->len) { + err = insert_old_idx(c, zbr->lnum, zbr->offs); + if (err) + return err; + zbr->lnum = 0; + zbr->offs = 0; + zbr->len = 0; + } + } else + if (c->zroot.len) { + err = insert_old_idx(c, c->zroot.lnum, c->zroot.offs); + if (err) + return err; + c->zroot.lnum = 0; + c->zroot.offs = 0; + c->zroot.len = 0; + } + return 0; +} + +/** + * destroy_old_idx - destroy the old_idx RB-tree. + * @c: UBIFS file-system description object + * + * During start commit, the old_idx RB-tree is used to avoid overwriting index + * nodes that were in the index last commit but have since been deleted. This + * is necessary for recovery i.e. the old index must be kept intact until the + * new index is successfully written. The old-idx RB-tree is used for the + * in-the-gaps method of writing index nodes and is destroyed every commit. + */ +void destroy_old_idx(struct ubifs_info *c) +{ + struct ubifs_old_idx *old_idx, *n; + + rbtree_postorder_for_each_entry_safe(old_idx, n, &c->old_idx, rb) + kfree(old_idx); + + c->old_idx = RB_ROOT; +} + +/** + * copy_znode - copy a dirty znode. + * @c: UBIFS file-system description object + * @znode: znode to copy + * + * A dirty znode being committed may not be changed, so it is copied. + */ +static struct ubifs_znode *copy_znode(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + struct ubifs_znode *zn; + + zn = kmemdup(znode, c->max_znode_sz, GFP_NOFS); + if (unlikely(!zn)) + return ERR_PTR(-ENOMEM); + + zn->cnext = NULL; + __set_bit(DIRTY_ZNODE, &zn->flags); + __clear_bit(COW_ZNODE, &zn->flags); + + return zn; +} + +/** + * add_idx_dirt - add dirt due to a dirty znode. + * @c: UBIFS file-system description object + * @lnum: LEB number of index node + * @dirt: size of index node + * + * This function updates lprops dirty space and the new size of the index. + */ +static int add_idx_dirt(struct ubifs_info *c, int lnum, int dirt) +{ + c->calc_idx_sz -= ALIGN(dirt, 8); + return ubifs_add_dirt(c, lnum, dirt); +} + +/** + * replace_znode - replace old znode with new znode. + * @c: UBIFS file-system description object + * @new_zn: new znode + * @old_zn: old znode + * @zbr: the branch of parent znode + * + * Replace old znode with new znode in TNC. + */ +static void replace_znode(struct ubifs_info *c, struct ubifs_znode *new_zn, + struct ubifs_znode *old_zn, struct ubifs_zbranch *zbr) +{ + ubifs_assert(c, !ubifs_zn_obsolete(old_zn)); + __set_bit(OBSOLETE_ZNODE, &old_zn->flags); + + if (old_zn->level != 0) { + int i; + const int n = new_zn->child_cnt; + + /* The children now have new parent */ + for (i = 0; i < n; i++) { + struct ubifs_zbranch *child = &new_zn->zbranch[i]; + + if (child->znode) + child->znode->parent = new_zn; + } + } + + zbr->znode = new_zn; + zbr->lnum = 0; + zbr->offs = 0; + zbr->len = 0; + + atomic_long_inc(&c->dirty_zn_cnt); +} + +/** + * dirty_cow_znode - ensure a znode is not being committed. + * @c: UBIFS file-system description object + * @zbr: branch of znode to check + * + * Returns dirtied znode on success or negative error code on failure. + */ +static struct ubifs_znode *dirty_cow_znode(struct ubifs_info *c, + struct ubifs_zbranch *zbr) +{ + struct ubifs_znode *znode = zbr->znode; + struct ubifs_znode *zn; + int err; + + if (!ubifs_zn_cow(znode)) { + /* znode is not being committed */ + if (!test_and_set_bit(DIRTY_ZNODE, &znode->flags)) { + atomic_long_inc(&c->dirty_zn_cnt); + atomic_long_dec(&c->clean_zn_cnt); + atomic_long_dec(&ubifs_clean_zn_cnt); + err = add_idx_dirt(c, zbr->lnum, zbr->len); + if (unlikely(err)) + return ERR_PTR(err); + } + return znode; + } + + zn = copy_znode(c, znode); + if (IS_ERR(zn)) + return zn; + + if (zbr->len) { + struct ubifs_old_idx *old_idx; + + old_idx = kmalloc(sizeof(struct ubifs_old_idx), GFP_NOFS); + if (unlikely(!old_idx)) { + err = -ENOMEM; + goto out; + } + old_idx->lnum = zbr->lnum; + old_idx->offs = zbr->offs; + + err = add_idx_dirt(c, zbr->lnum, zbr->len); + if (err) { + kfree(old_idx); + goto out; + } + + do_insert_old_idx(c, old_idx); + } + + replace_znode(c, zn, znode, zbr); + + return zn; + +out: + kfree(zn); + return ERR_PTR(err); +} + +/** + * lnc_add - add a leaf node to the leaf node cache. + * @c: UBIFS file-system description object + * @zbr: zbranch of leaf node + * @node: leaf node + * + * Leaf nodes are non-index nodes directory entry nodes or data nodes. The + * purpose of the leaf node cache is to save re-reading the same leaf node over + * and over again. Most things are cached by VFS, however the file system must + * cache directory entries for readdir and for resolving hash collisions. The + * present implementation of the leaf node cache is extremely simple, and + * allows for error returns that are not used but that may be needed if a more + * complex implementation is created. + * + * Note, this function does not add the @node object to LNC directly, but + * allocates a copy of the object and adds the copy to LNC. The reason for this + * is that @node has been allocated outside of the TNC subsystem and will be + * used with @c->tnc_mutex unlock upon return from the TNC subsystem. But LNC + * may be changed at any time, e.g. freed by the shrinker. + */ +static int lnc_add(struct ubifs_info *c, struct ubifs_zbranch *zbr, + const void *node) +{ + int err; + void *lnc_node; + const struct ubifs_dent_node *dent = node; + + ubifs_assert(c, !zbr->leaf); + ubifs_assert(c, zbr->len != 0); + ubifs_assert(c, is_hash_key(c, &zbr->key)); + + err = ubifs_validate_entry(c, dent); + if (err) { + dump_stack(); + ubifs_dump_node(c, dent, zbr->len); + return err; + } + + lnc_node = kmemdup(node, zbr->len, GFP_NOFS); + if (!lnc_node) + /* We don't have to have the cache, so no error */ + return 0; + + zbr->leaf = lnc_node; + return 0; +} + + /** + * lnc_add_directly - add a leaf node to the leaf-node-cache. + * @c: UBIFS file-system description object + * @zbr: zbranch of leaf node + * @node: leaf node + * + * This function is similar to 'lnc_add()', but it does not create a copy of + * @node but inserts @node to TNC directly. + */ +static int lnc_add_directly(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node) +{ + int err; + + ubifs_assert(c, !zbr->leaf); + ubifs_assert(c, zbr->len != 0); + + err = ubifs_validate_entry(c, node); + if (err) { + dump_stack(); + ubifs_dump_node(c, node, zbr->len); + return err; + } + + zbr->leaf = node; + return 0; +} + +/** + * lnc_free - remove a leaf node from the leaf node cache. + * @zbr: zbranch of leaf node + */ +static void lnc_free(struct ubifs_zbranch *zbr) +{ + if (!zbr->leaf) + return; + kfree(zbr->leaf); + zbr->leaf = NULL; +} + +/** + * tnc_read_hashed_node - read a "hashed" leaf node. + * @c: UBIFS file-system description object + * @zbr: key and position of the node + * @node: node is returned here + * + * This function reads a "hashed" node defined by @zbr from the leaf node cache + * (in it is there) or from the hash media, in which case the node is also + * added to LNC. Returns zero in case of success or a negative error + * code in case of failure. + */ +static int tnc_read_hashed_node(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node) +{ + int err; + + ubifs_assert(c, is_hash_key(c, &zbr->key)); + + if (zbr->leaf) { + /* Read from the leaf node cache */ + ubifs_assert(c, zbr->len != 0); + memcpy(node, zbr->leaf, zbr->len); + return 0; + } + + if (c->replaying) { + err = fallible_read_node(c, &zbr->key, zbr, node); + /* + * When the node was not found, return -ENOENT, 0 otherwise. + * Negative return codes stay as-is. + */ + if (err == 0) + err = -ENOENT; + else if (err == 1) + err = 0; + } else { + err = ubifs_tnc_read_node(c, zbr, node); + } + if (err) + return err; + + /* Add the node to the leaf node cache */ + err = lnc_add(c, zbr, node); + return err; +} + +/** + * try_read_node - read a node if it is a node. + * @c: UBIFS file-system description object + * @buf: buffer to read to + * @type: node type + * @zbr: the zbranch describing the node to read + * + * This function tries to read a node of known type and length, checks it and + * stores it in @buf. This function returns %1 if a node is present and %0 if + * a node is not present. A negative error code is returned for I/O errors. + * This function performs that same function as ubifs_read_node except that + * it does not require that there is actually a node present and instead + * the return code indicates if a node was read. + * + * Note, this function does not check CRC of data nodes if @c->no_chk_data_crc + * is true (it is controlled by corresponding mount option). However, if + * @c->mounting or @c->remounting_rw is true (we are mounting or re-mounting to + * R/W mode), @c->no_chk_data_crc is ignored and CRC is checked. This is + * because during mounting or re-mounting from R/O mode to R/W mode we may read + * journal nodes (when replying the journal or doing the recovery) and the + * journal nodes may potentially be corrupted, so checking is required. + */ +static int try_read_node(const struct ubifs_info *c, void *buf, int type, + struct ubifs_zbranch *zbr) +{ + int len = zbr->len; + int lnum = zbr->lnum; + int offs = zbr->offs; + int err, node_len; + struct ubifs_ch *ch = buf; + uint32_t crc, node_crc; + + dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len); + + err = ubifs_leb_read(c, lnum, buf, offs, len, 1); + if (err && err != -EBADMSG) { + ubifs_err(c, "cannot read node type %d from LEB %d:%d, error %d", + type, lnum, offs, err); + return err; + } + + if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) + return 0; + + if (ch->node_type != type) + return 0; + + node_len = le32_to_cpu(ch->len); + if (node_len != len) + return 0; + + if (type != UBIFS_DATA_NODE || !c->no_chk_data_crc || c->mounting || + c->remounting_rw) { + crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8); + node_crc = le32_to_cpu(ch->crc); + if (crc != node_crc) + return 0; + } + + err = ubifs_node_check_hash(c, buf, zbr->hash); + if (err) { + ubifs_bad_hash(c, buf, zbr->hash, lnum, offs); + return 0; + } + + return 1; +} + +/** + * fallible_read_node - try to read a leaf node. + * @c: UBIFS file-system description object + * @key: key of node to read + * @zbr: position of node + * @node: node returned + * + * This function tries to read a node and returns %1 if the node is read, %0 + * if the node is not present, and a negative error code in the case of error. + */ +static int fallible_read_node(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_zbranch *zbr, void *node) +{ + int ret; + + dbg_tnck(key, "LEB %d:%d, key ", zbr->lnum, zbr->offs); + + ret = try_read_node(c, node, key_type(c, key), zbr); + if (ret == 1) { + union ubifs_key node_key; + struct ubifs_dent_node *dent = node; + + /* All nodes have key in the same place */ + key_read(c, &dent->key, &node_key); + if (keys_cmp(c, key, &node_key) != 0) + ret = 0; + } + if (ret == 0 && c->replaying) + dbg_mntk(key, "dangling branch LEB %d:%d len %d, key ", + zbr->lnum, zbr->offs, zbr->len); + return ret; +} + +/** + * matches_name - determine if a direntry or xattr entry matches a given name. + * @c: UBIFS file-system description object + * @zbr: zbranch of dent + * @nm: name to match + * + * This function checks if xentry/direntry referred by zbranch @zbr matches name + * @nm. Returns %NAME_MATCHES if it does, %NAME_LESS if the name referred by + * @zbr is less than @nm, and %NAME_GREATER if it is greater than @nm. In case + * of failure, a negative error code is returned. + */ +static int matches_name(struct ubifs_info *c, struct ubifs_zbranch *zbr, + const struct fscrypt_name *nm) +{ + struct ubifs_dent_node *dent; + int nlen, err; + + /* If possible, match against the dent in the leaf node cache */ + if (!zbr->leaf) { + dent = kmalloc(zbr->len, GFP_NOFS); + if (!dent) + return -ENOMEM; + + err = ubifs_tnc_read_node(c, zbr, dent); + if (err) + goto out_free; + + /* Add the node to the leaf node cache */ + err = lnc_add_directly(c, zbr, dent); + if (err) + goto out_free; + } else + dent = zbr->leaf; + + nlen = le16_to_cpu(dent->nlen); + err = memcmp(dent->name, fname_name(nm), min_t(int, nlen, fname_len(nm))); + if (err == 0) { + if (nlen == fname_len(nm)) + return NAME_MATCHES; + else if (nlen < fname_len(nm)) + return NAME_LESS; + else + return NAME_GREATER; + } else if (err < 0) + return NAME_LESS; + else + return NAME_GREATER; + +out_free: + kfree(dent); + return err; +} + +/** + * get_znode - get a TNC znode that may not be loaded yet. + * @c: UBIFS file-system description object + * @znode: parent znode + * @n: znode branch slot number + * + * This function returns the znode or a negative error code. + */ +static struct ubifs_znode *get_znode(struct ubifs_info *c, + struct ubifs_znode *znode, int n) +{ + struct ubifs_zbranch *zbr; + + zbr = &znode->zbranch[n]; + if (zbr->znode) + znode = zbr->znode; + else + znode = ubifs_load_znode(c, zbr, znode, n); + return znode; +} + +/** + * tnc_next - find next TNC entry. + * @c: UBIFS file-system description object + * @zn: znode is passed and returned here + * @n: znode branch slot number is passed and returned here + * + * This function returns %0 if the next TNC entry is found, %-ENOENT if there is + * no next entry, or a negative error code otherwise. + */ +static int tnc_next(struct ubifs_info *c, struct ubifs_znode **zn, int *n) +{ + struct ubifs_znode *znode = *zn; + int nn = *n; + + nn += 1; + if (nn < znode->child_cnt) { + *n = nn; + return 0; + } + while (1) { + struct ubifs_znode *zp; + + zp = znode->parent; + if (!zp) + return -ENOENT; + nn = znode->iip + 1; + znode = zp; + if (nn < znode->child_cnt) { + znode = get_znode(c, znode, nn); + if (IS_ERR(znode)) + return PTR_ERR(znode); + while (znode->level != 0) { + znode = get_znode(c, znode, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + nn = 0; + break; + } + } + *zn = znode; + *n = nn; + return 0; +} + +/** + * tnc_prev - find previous TNC entry. + * @c: UBIFS file-system description object + * @zn: znode is returned here + * @n: znode branch slot number is passed and returned here + * + * This function returns %0 if the previous TNC entry is found, %-ENOENT if + * there is no next entry, or a negative error code otherwise. + */ +static int tnc_prev(struct ubifs_info *c, struct ubifs_znode **zn, int *n) +{ + struct ubifs_znode *znode = *zn; + int nn = *n; + + if (nn > 0) { + *n = nn - 1; + return 0; + } + while (1) { + struct ubifs_znode *zp; + + zp = znode->parent; + if (!zp) + return -ENOENT; + nn = znode->iip - 1; + znode = zp; + if (nn >= 0) { + znode = get_znode(c, znode, nn); + if (IS_ERR(znode)) + return PTR_ERR(znode); + while (znode->level != 0) { + nn = znode->child_cnt - 1; + znode = get_znode(c, znode, nn); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + nn = znode->child_cnt - 1; + break; + } + } + *zn = znode; + *n = nn; + return 0; +} + +/** + * resolve_collision - resolve a collision. + * @c: UBIFS file-system description object + * @key: key of a directory or extended attribute entry + * @zn: znode is returned here + * @n: zbranch number is passed and returned here + * @nm: name of the entry + * + * This function is called for "hashed" keys to make sure that the found key + * really corresponds to the looked up node (directory or extended attribute + * entry). It returns %1 and sets @zn and @n if the collision is resolved. + * %0 is returned if @nm is not found and @zn and @n are set to the previous + * entry, i.e. to the entry after which @nm could follow if it were in TNC. + * This means that @n may be set to %-1 if the leftmost key in @zn is the + * previous one. A negative error code is returned on failures. + */ +static int resolve_collision(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n, + const struct fscrypt_name *nm) +{ + int err; + + err = matches_name(c, &(*zn)->zbranch[*n], nm); + if (unlikely(err < 0)) + return err; + if (err == NAME_MATCHES) + return 1; + + if (err == NAME_GREATER) { + /* Look left */ + while (1) { + err = tnc_prev(c, zn, n); + if (err == -ENOENT) { + ubifs_assert(c, *n == 0); + *n = -1; + return 0; + } + if (err < 0) + return err; + if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) { + /* + * We have found the branch after which we would + * like to insert, but inserting in this znode + * may still be wrong. Consider the following 3 + * znodes, in the case where we are resolving a + * collision with Key2. + * + * znode zp + * ---------------------- + * level 1 | Key0 | Key1 | + * ----------------------- + * | | + * znode za | | znode zb + * ------------ ------------ + * level 0 | Key0 | | Key2 | + * ------------ ------------ + * + * The lookup finds Key2 in znode zb. Lets say + * there is no match and the name is greater so + * we look left. When we find Key0, we end up + * here. If we return now, we will insert into + * znode za at slot n = 1. But that is invalid + * according to the parent's keys. Key2 must + * be inserted into znode zb. + * + * Note, this problem is not relevant for the + * case when we go right, because + * 'tnc_insert()' would correct the parent key. + */ + if (*n == (*zn)->child_cnt - 1) { + err = tnc_next(c, zn, n); + if (err) { + /* Should be impossible */ + ubifs_assert(c, 0); + if (err == -ENOENT) + err = -EINVAL; + return err; + } + ubifs_assert(c, *n == 0); + *n = -1; + } + return 0; + } + err = matches_name(c, &(*zn)->zbranch[*n], nm); + if (err < 0) + return err; + if (err == NAME_LESS) + return 0; + if (err == NAME_MATCHES) + return 1; + ubifs_assert(c, err == NAME_GREATER); + } + } else { + int nn = *n; + struct ubifs_znode *znode = *zn; + + /* Look right */ + while (1) { + err = tnc_next(c, &znode, &nn); + if (err == -ENOENT) + return 0; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + return 0; + err = matches_name(c, &znode->zbranch[nn], nm); + if (err < 0) + return err; + if (err == NAME_GREATER) + return 0; + *zn = znode; + *n = nn; + if (err == NAME_MATCHES) + return 1; + ubifs_assert(c, err == NAME_LESS); + } + } +} + +/** + * fallible_matches_name - determine if a dent matches a given name. + * @c: UBIFS file-system description object + * @zbr: zbranch of dent + * @nm: name to match + * + * This is a "fallible" version of 'matches_name()' function which does not + * panic if the direntry/xentry referred by @zbr does not exist on the media. + * + * This function checks if xentry/direntry referred by zbranch @zbr matches name + * @nm. Returns %NAME_MATCHES it does, %NAME_LESS if the name referred by @zbr + * is less than @nm, %NAME_GREATER if it is greater than @nm, and @NOT_ON_MEDIA + * if xentry/direntry referred by @zbr does not exist on the media. A negative + * error code is returned in case of failure. + */ +static int fallible_matches_name(struct ubifs_info *c, + struct ubifs_zbranch *zbr, + const struct fscrypt_name *nm) +{ + struct ubifs_dent_node *dent; + int nlen, err; + + /* If possible, match against the dent in the leaf node cache */ + if (!zbr->leaf) { + dent = kmalloc(zbr->len, GFP_NOFS); + if (!dent) + return -ENOMEM; + + err = fallible_read_node(c, &zbr->key, zbr, dent); + if (err < 0) + goto out_free; + if (err == 0) { + /* The node was not present */ + err = NOT_ON_MEDIA; + goto out_free; + } + ubifs_assert(c, err == 1); + + err = lnc_add_directly(c, zbr, dent); + if (err) + goto out_free; + } else + dent = zbr->leaf; + + nlen = le16_to_cpu(dent->nlen); + err = memcmp(dent->name, fname_name(nm), min_t(int, nlen, fname_len(nm))); + if (err == 0) { + if (nlen == fname_len(nm)) + return NAME_MATCHES; + else if (nlen < fname_len(nm)) + return NAME_LESS; + else + return NAME_GREATER; + } else if (err < 0) + return NAME_LESS; + else + return NAME_GREATER; + +out_free: + kfree(dent); + return err; +} + +/** + * fallible_resolve_collision - resolve a collision even if nodes are missing. + * @c: UBIFS file-system description object + * @key: key + * @zn: znode is returned here + * @n: branch number is passed and returned here + * @nm: name of directory entry + * @adding: indicates caller is adding a key to the TNC + * + * This is a "fallible" version of the 'resolve_collision()' function which + * does not panic if one of the nodes referred to by TNC does not exist on the + * media. This may happen when replaying the journal if a deleted node was + * Garbage-collected and the commit was not done. A branch that refers to a node + * that is not present is called a dangling branch. The following are the return + * codes for this function: + * o if @nm was found, %1 is returned and @zn and @n are set to the found + * branch; + * o if we are @adding and @nm was not found, %0 is returned; + * o if we are not @adding and @nm was not found, but a dangling branch was + * found, then %1 is returned and @zn and @n are set to the dangling branch; + * o a negative error code is returned in case of failure. + */ +static int fallible_resolve_collision(struct ubifs_info *c, + const union ubifs_key *key, + struct ubifs_znode **zn, int *n, + const struct fscrypt_name *nm, + int adding) +{ + struct ubifs_znode *o_znode = NULL, *znode = *zn; + int err, cmp, o_n = 0, unsure = 0, nn = *n; + + cmp = fallible_matches_name(c, &znode->zbranch[nn], nm); + if (unlikely(cmp < 0)) + return cmp; + if (cmp == NAME_MATCHES) + return 1; + if (cmp == NOT_ON_MEDIA) { + o_znode = znode; + o_n = nn; + /* + * We are unlucky and hit a dangling branch straight away. + * Now we do not really know where to go to find the needed + * branch - to the left or to the right. Well, let's try left. + */ + unsure = 1; + } else if (!adding) + unsure = 1; /* Remove a dangling branch wherever it is */ + + if (cmp == NAME_GREATER || unsure) { + /* Look left */ + while (1) { + err = tnc_prev(c, zn, n); + if (err == -ENOENT) { + ubifs_assert(c, *n == 0); + *n = -1; + break; + } + if (err < 0) + return err; + if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) { + /* See comments in 'resolve_collision()' */ + if (*n == (*zn)->child_cnt - 1) { + err = tnc_next(c, zn, n); + if (err) { + /* Should be impossible */ + ubifs_assert(c, 0); + if (err == -ENOENT) + err = -EINVAL; + return err; + } + ubifs_assert(c, *n == 0); + *n = -1; + } + break; + } + err = fallible_matches_name(c, &(*zn)->zbranch[*n], nm); + if (err < 0) + return err; + if (err == NAME_MATCHES) + return 1; + if (err == NOT_ON_MEDIA) { + o_znode = *zn; + o_n = *n; + continue; + } + if (!adding) + continue; + if (err == NAME_LESS) + break; + else + unsure = 0; + } + } + + if (cmp == NAME_LESS || unsure) { + /* Look right */ + *zn = znode; + *n = nn; + while (1) { + err = tnc_next(c, &znode, &nn); + if (err == -ENOENT) + break; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + break; + err = fallible_matches_name(c, &znode->zbranch[nn], nm); + if (err < 0) + return err; + if (err == NAME_GREATER) + break; + *zn = znode; + *n = nn; + if (err == NAME_MATCHES) + return 1; + if (err == NOT_ON_MEDIA) { + o_znode = znode; + o_n = nn; + } + } + } + + /* Never match a dangling branch when adding */ + if (adding || !o_znode) + return 0; + + dbg_mntk(key, "dangling match LEB %d:%d len %d key ", + o_znode->zbranch[o_n].lnum, o_znode->zbranch[o_n].offs, + o_znode->zbranch[o_n].len); + *zn = o_znode; + *n = o_n; + return 1; +} + +/** + * matches_position - determine if a zbranch matches a given position. + * @zbr: zbranch of dent + * @lnum: LEB number of dent to match + * @offs: offset of dent to match + * + * This function returns %1 if @lnum:@offs matches, and %0 otherwise. + */ +static int matches_position(struct ubifs_zbranch *zbr, int lnum, int offs) +{ + if (zbr->lnum == lnum && zbr->offs == offs) + return 1; + else + return 0; +} + +/** + * resolve_collision_directly - resolve a collision directly. + * @c: UBIFS file-system description object + * @key: key of directory entry + * @zn: znode is passed and returned here + * @n: zbranch number is passed and returned here + * @lnum: LEB number of dent node to match + * @offs: offset of dent node to match + * + * This function is used for "hashed" keys to make sure the found directory or + * extended attribute entry node is what was looked for. It is used when the + * flash address of the right node is known (@lnum:@offs) which makes it much + * easier to resolve collisions (no need to read entries and match full + * names). This function returns %1 and sets @zn and @n if the collision is + * resolved, %0 if @lnum:@offs is not found and @zn and @n are set to the + * previous directory entry. Otherwise a negative error code is returned. + */ +static int resolve_collision_directly(struct ubifs_info *c, + const union ubifs_key *key, + struct ubifs_znode **zn, int *n, + int lnum, int offs) +{ + struct ubifs_znode *znode; + int nn, err; + + znode = *zn; + nn = *n; + if (matches_position(&znode->zbranch[nn], lnum, offs)) + return 1; + + /* Look left */ + while (1) { + err = tnc_prev(c, &znode, &nn); + if (err == -ENOENT) + break; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + break; + if (matches_position(&znode->zbranch[nn], lnum, offs)) { + *zn = znode; + *n = nn; + return 1; + } + } + + /* Look right */ + znode = *zn; + nn = *n; + while (1) { + err = tnc_next(c, &znode, &nn); + if (err == -ENOENT) + return 0; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + return 0; + *zn = znode; + *n = nn; + if (matches_position(&znode->zbranch[nn], lnum, offs)) + return 1; + } +} + +/** + * dirty_cow_bottom_up - dirty a znode and its ancestors. + * @c: UBIFS file-system description object + * @znode: znode to dirty + * + * If we do not have a unique key that resides in a znode, then we cannot + * dirty that znode from the top down (i.e. by using lookup_level0_dirty) + * This function records the path back to the last dirty ancestor, and then + * dirties the znodes on that path. + */ +static struct ubifs_znode *dirty_cow_bottom_up(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + struct ubifs_znode *zp; + int *path = c->bottom_up_buf, p = 0; + + ubifs_assert(c, c->zroot.znode); + ubifs_assert(c, znode); + if (c->zroot.znode->level > BOTTOM_UP_HEIGHT) { + kfree(c->bottom_up_buf); + c->bottom_up_buf = kmalloc_array(c->zroot.znode->level, + sizeof(int), + GFP_NOFS); + if (!c->bottom_up_buf) + return ERR_PTR(-ENOMEM); + path = c->bottom_up_buf; + } + if (c->zroot.znode->level) { + /* Go up until parent is dirty */ + while (1) { + int n; + + zp = znode->parent; + if (!zp) + break; + n = znode->iip; + ubifs_assert(c, p < c->zroot.znode->level); + path[p++] = n; + if (!zp->cnext && ubifs_zn_dirty(znode)) + break; + znode = zp; + } + } + + /* Come back down, dirtying as we go */ + while (1) { + struct ubifs_zbranch *zbr; + + zp = znode->parent; + if (zp) { + ubifs_assert(c, path[p - 1] >= 0); + ubifs_assert(c, path[p - 1] < zp->child_cnt); + zbr = &zp->zbranch[path[--p]]; + znode = dirty_cow_znode(c, zbr); + } else { + ubifs_assert(c, znode == c->zroot.znode); + znode = dirty_cow_znode(c, &c->zroot); + } + if (IS_ERR(znode) || !p) + break; + ubifs_assert(c, path[p - 1] >= 0); + ubifs_assert(c, path[p - 1] < znode->child_cnt); + znode = znode->zbranch[path[p - 1]].znode; + } + + return znode; +} + +/** + * ubifs_lookup_level0 - search for zero-level znode. + * @c: UBIFS file-system description object + * @key: key to lookup + * @zn: znode is returned here + * @n: znode branch slot number is returned here + * + * This function looks up the TNC tree and search for zero-level znode which + * refers key @key. The found zero-level znode is returned in @zn. There are 3 + * cases: + * o exact match, i.e. the found zero-level znode contains key @key, then %1 + * is returned and slot number of the matched branch is stored in @n; + * o not exact match, which means that zero-level znode does not contain + * @key, then %0 is returned and slot number of the closest branch or %-1 + * is stored in @n; In this case calling tnc_next() is mandatory. + * o @key is so small that it is even less than the lowest key of the + * leftmost zero-level node, then %0 is returned and %0 is stored in @n. + * + * Note, when the TNC tree is traversed, some znodes may be absent, then this + * function reads corresponding indexing nodes and inserts them to TNC. In + * case of failure, a negative error code is returned. + */ +int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n) +{ + int err, exact; + struct ubifs_znode *znode; + time64_t time = ktime_get_seconds(); + + dbg_tnck(key, "search key "); + ubifs_assert(c, key_type(c, key) < UBIFS_INVALID_KEY); + + znode = c->zroot.znode; + if (unlikely(!znode)) { + znode = ubifs_load_znode(c, &c->zroot, NULL, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + znode->time = time; + + while (1) { + struct ubifs_zbranch *zbr; + + exact = ubifs_search_zbranch(c, znode, key, n); + + if (znode->level == 0) + break; + + if (*n < 0) + *n = 0; + zbr = &znode->zbranch[*n]; + + if (zbr->znode) { + znode->time = time; + znode = zbr->znode; + continue; + } + + /* znode is not in TNC cache, load it from the media */ + znode = ubifs_load_znode(c, zbr, znode, *n); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + *zn = znode; + if (exact || !is_hash_key(c, key) || *n != -1) { + dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n); + return exact; + } + + /* + * Here is a tricky place. We have not found the key and this is a + * "hashed" key, which may collide. The rest of the code deals with + * situations like this: + * + * | 3 | 5 | + * / \ + * | 3 | 5 | | 6 | 7 | (x) + * + * Or more a complex example: + * + * | 1 | 5 | + * / \ + * | 1 | 3 | | 5 | 8 | + * \ / + * | 5 | 5 | | 6 | 7 | (x) + * + * In the examples, if we are looking for key "5", we may reach nodes + * marked with "(x)". In this case what we have do is to look at the + * left and see if there is "5" key there. If there is, we have to + * return it. + * + * Note, this whole situation is possible because we allow to have + * elements which are equivalent to the next key in the parent in the + * children of current znode. For example, this happens if we split a + * znode like this: | 3 | 5 | 5 | 6 | 7 |, which results in something + * like this: + * | 3 | 5 | + * / \ + * | 3 | 5 | | 5 | 6 | 7 | + * ^ + * And this becomes what is at the first "picture" after key "5" marked + * with "^" is removed. What could be done is we could prohibit + * splitting in the middle of the colliding sequence. Also, when + * removing the leftmost key, we would have to correct the key of the + * parent node, which would introduce additional complications. Namely, + * if we changed the leftmost key of the parent znode, the garbage + * collector would be unable to find it (GC is doing this when GC'ing + * indexing LEBs). Although we already have an additional RB-tree where + * we save such changed znodes (see 'ins_clr_old_idx_znode()') until + * after the commit. But anyway, this does not look easy to implement + * so we did not try this. + */ + err = tnc_prev(c, &znode, n); + if (err == -ENOENT) { + dbg_tnc("found 0, lvl %d, n -1", znode->level); + *n = -1; + return 0; + } + if (unlikely(err < 0)) + return err; + if (keys_cmp(c, key, &znode->zbranch[*n].key)) { + dbg_tnc("found 0, lvl %d, n -1", znode->level); + *n = -1; + return 0; + } + + dbg_tnc("found 1, lvl %d, n %d", znode->level, *n); + *zn = znode; + return 1; +} + +/** + * lookup_level0_dirty - search for zero-level znode dirtying. + * @c: UBIFS file-system description object + * @key: key to lookup + * @zn: znode is returned here + * @n: znode branch slot number is returned here + * + * This function looks up the TNC tree and search for zero-level znode which + * refers key @key. The found zero-level znode is returned in @zn. There are 3 + * cases: + * o exact match, i.e. the found zero-level znode contains key @key, then %1 + * is returned and slot number of the matched branch is stored in @n; + * o not exact match, which means that zero-level znode does not contain @key + * then %0 is returned and slot number of the closed branch is stored in + * @n; + * o @key is so small that it is even less than the lowest key of the + * leftmost zero-level node, then %0 is returned and %-1 is stored in @n. + * + * Additionally all znodes in the path from the root to the located zero-level + * znode are marked as dirty. + * + * Note, when the TNC tree is traversed, some znodes may be absent, then this + * function reads corresponding indexing nodes and inserts them to TNC. In + * case of failure, a negative error code is returned. + */ +static int lookup_level0_dirty(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n) +{ + int err, exact; + struct ubifs_znode *znode; + time64_t time = ktime_get_seconds(); + + dbg_tnck(key, "search and dirty key "); + + znode = c->zroot.znode; + if (unlikely(!znode)) { + znode = ubifs_load_znode(c, &c->zroot, NULL, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + znode = dirty_cow_znode(c, &c->zroot); + if (IS_ERR(znode)) + return PTR_ERR(znode); + + znode->time = time; + + while (1) { + struct ubifs_zbranch *zbr; + + exact = ubifs_search_zbranch(c, znode, key, n); + + if (znode->level == 0) + break; + + if (*n < 0) + *n = 0; + zbr = &znode->zbranch[*n]; + + if (zbr->znode) { + znode->time = time; + znode = dirty_cow_znode(c, zbr); + if (IS_ERR(znode)) + return PTR_ERR(znode); + continue; + } + + /* znode is not in TNC cache, load it from the media */ + znode = ubifs_load_znode(c, zbr, znode, *n); + if (IS_ERR(znode)) + return PTR_ERR(znode); + znode = dirty_cow_znode(c, zbr); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + *zn = znode; + if (exact || !is_hash_key(c, key) || *n != -1) { + dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n); + return exact; + } + + /* + * See huge comment at 'lookup_level0_dirty()' what is the rest of the + * code. + */ + err = tnc_prev(c, &znode, n); + if (err == -ENOENT) { + *n = -1; + dbg_tnc("found 0, lvl %d, n -1", znode->level); + return 0; + } + if (unlikely(err < 0)) + return err; + if (keys_cmp(c, key, &znode->zbranch[*n].key)) { + *n = -1; + dbg_tnc("found 0, lvl %d, n -1", znode->level); + return 0; + } + + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + dbg_tnc("found 1, lvl %d, n %d", znode->level, *n); + *zn = znode; + return 1; +} + +/** + * ubifs_tnc_locate - look up a file-system node and return it and its location. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * @lnum: LEB number is returned here + * @offs: offset is returned here + * + * This function looks up and reads node with key @key. The caller has to make + * sure the @node buffer is large enough to fit the node. Returns zero in case + * of success, %-ENOENT if the node was not found, and a negative error code in + * case of failure. The node location can be returned in @lnum and @offs. + */ +int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key, + void *node, int *lnum, int *offs) +{ + int found, n, err; + struct ubifs_znode *znode; + struct ubifs_zbranch *zt; + + mutex_lock(&c->tnc_mutex); + found = ubifs_lookup_level0(c, key, &znode, &n); + if (!found) { + err = -ENOENT; + goto out; + } else if (found < 0) { + err = found; + goto out; + } + zt = &znode->zbranch[n]; + if (lnum) { + *lnum = zt->lnum; + *offs = zt->offs; + } + if (is_hash_key(c, key)) { + /* + * In this case the leaf node cache gets used, so we pass the + * address of the zbranch and keep the mutex locked + */ + err = tnc_read_hashed_node(c, zt, node); + goto out; + } + err = ubifs_tnc_read_node(c, zt, node); + +out: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * do_lookup_nm- look up a "hashed" node. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * @nm: node name + * + * This function looks up and reads a node which contains name hash in the key. + * Since the hash may have collisions, there may be many nodes with the same + * key, so we have to sequentially look to all of them until the needed one is + * found. This function returns zero in case of success, %-ENOENT if the node + * was not found, and a negative error code in case of failure. + */ +static int do_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, + void *node, const struct fscrypt_name *nm) +{ + int found, n, err; + struct ubifs_znode *znode; + + dbg_tnck(key, "key "); + mutex_lock(&c->tnc_mutex); + found = ubifs_lookup_level0(c, key, &znode, &n); + if (!found) { + err = -ENOENT; + goto out_unlock; + } else if (found < 0) { + err = found; + goto out_unlock; + } + + ubifs_assert(c, n >= 0); + + err = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n); + if (unlikely(err < 0)) + goto out_unlock; + if (err == 0) { + err = -ENOENT; + goto out_unlock; + } + + err = tnc_read_hashed_node(c, &znode->zbranch[n], node); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_lookup_nm - look up a "hashed" node. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * @nm: node name + * + * This function looks up and reads a node which contains name hash in the key. + * Since the hash may have collisions, there may be many nodes with the same + * key, so we have to sequentially look to all of them until the needed one is + * found. This function returns zero in case of success, %-ENOENT if the node + * was not found, and a negative error code in case of failure. + */ +int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, + void *node, const struct fscrypt_name *nm) +{ + int err, len; + const struct ubifs_dent_node *dent = node; + + /* + * We assume that in most of the cases there are no name collisions and + * 'ubifs_tnc_lookup()' returns us the right direntry. + */ + err = ubifs_tnc_lookup(c, key, node); + if (err) + return err; + + len = le16_to_cpu(dent->nlen); + if (fname_len(nm) == len && !memcmp(dent->name, fname_name(nm), len)) + return 0; + + /* + * Unluckily, there are hash collisions and we have to iterate over + * them look at each direntry with colliding name hash sequentially. + */ + + return do_lookup_nm(c, key, node, nm); +} + +/** + * correct_parent_keys - correct parent znodes' keys. + * @c: UBIFS file-system description object + * @znode: znode to correct parent znodes for + * + * This is a helper function for 'tnc_insert()'. When the key of the leftmost + * zbranch changes, keys of parent znodes have to be corrected. This helper + * function is called in such situations and corrects the keys if needed. + */ +static void correct_parent_keys(const struct ubifs_info *c, + struct ubifs_znode *znode) +{ + union ubifs_key *key, *key1; + + ubifs_assert(c, znode->parent); + ubifs_assert(c, znode->iip == 0); + + key = &znode->zbranch[0].key; + key1 = &znode->parent->zbranch[0].key; + + while (keys_cmp(c, key, key1) < 0) { + key_copy(c, key, key1); + znode = znode->parent; + znode->alt = 1; + if (!znode->parent || znode->iip) + break; + key1 = &znode->parent->zbranch[0].key; + } +} + +/** + * insert_zbranch - insert a zbranch into a znode. + * @c: UBIFS file-system description object + * @znode: znode into which to insert + * @zbr: zbranch to insert + * @n: slot number to insert to + * + * This is a helper function for 'tnc_insert()'. UBIFS does not allow "gaps" in + * znode's array of zbranches and keeps zbranches consolidated, so when a new + * zbranch has to be inserted to the @znode->zbranches[]' array at the @n-th + * slot, zbranches starting from @n have to be moved right. + */ +static void insert_zbranch(struct ubifs_info *c, struct ubifs_znode *znode, + const struct ubifs_zbranch *zbr, int n) +{ + int i; + + ubifs_assert(c, ubifs_zn_dirty(znode)); + + if (znode->level) { + for (i = znode->child_cnt; i > n; i--) { + znode->zbranch[i] = znode->zbranch[i - 1]; + if (znode->zbranch[i].znode) + znode->zbranch[i].znode->iip = i; + } + if (zbr->znode) + zbr->znode->iip = n; + } else + for (i = znode->child_cnt; i > n; i--) + znode->zbranch[i] = znode->zbranch[i - 1]; + + znode->zbranch[n] = *zbr; + znode->child_cnt += 1; + + /* + * After inserting at slot zero, the lower bound of the key range of + * this znode may have changed. If this znode is subsequently split + * then the upper bound of the key range may change, and furthermore + * it could change to be lower than the original lower bound. If that + * happens, then it will no longer be possible to find this znode in the + * TNC using the key from the index node on flash. That is bad because + * if it is not found, we will assume it is obsolete and may overwrite + * it. Then if there is an unclean unmount, we will start using the + * old index which will be broken. + * + * So we first mark znodes that have insertions at slot zero, and then + * if they are split we add their lnum/offs to the old_idx tree. + */ + if (n == 0) + znode->alt = 1; +} + +/** + * tnc_insert - insert a node into TNC. + * @c: UBIFS file-system description object + * @znode: znode to insert into + * @zbr: branch to insert + * @n: slot number to insert new zbranch to + * + * This function inserts a new node described by @zbr into znode @znode. If + * znode does not have a free slot for new zbranch, it is split. Parent znodes + * are splat as well if needed. Returns zero in case of success or a negative + * error code in case of failure. + */ +static int tnc_insert(struct ubifs_info *c, struct ubifs_znode *znode, + struct ubifs_zbranch *zbr, int n) +{ + struct ubifs_znode *zn, *zi, *zp; + int i, keep, move, appending = 0; + union ubifs_key *key = &zbr->key, *key1; + + ubifs_assert(c, n >= 0 && n <= c->fanout); + + /* Implement naive insert for now */ +again: + zp = znode->parent; + if (znode->child_cnt < c->fanout) { + ubifs_assert(c, n != c->fanout); + dbg_tnck(key, "inserted at %d level %d, key ", n, znode->level); + + insert_zbranch(c, znode, zbr, n); + + /* Ensure parent's key is correct */ + if (n == 0 && zp && znode->iip == 0) + correct_parent_keys(c, znode); + + return 0; + } + + /* + * Unfortunately, @znode does not have more empty slots and we have to + * split it. + */ + dbg_tnck(key, "splitting level %d, key ", znode->level); + + if (znode->alt) + /* + * We can no longer be sure of finding this znode by key, so we + * record it in the old_idx tree. + */ + ins_clr_old_idx_znode(c, znode); + + zn = kzalloc(c->max_znode_sz, GFP_NOFS); + if (!zn) + return -ENOMEM; + zn->parent = zp; + zn->level = znode->level; + + /* Decide where to split */ + if (znode->level == 0 && key_type(c, key) == UBIFS_DATA_KEY) { + /* Try not to split consecutive data keys */ + if (n == c->fanout) { + key1 = &znode->zbranch[n - 1].key; + if (key_inum(c, key1) == key_inum(c, key) && + key_type(c, key1) == UBIFS_DATA_KEY) + appending = 1; + } else + goto check_split; + } else if (appending && n != c->fanout) { + /* Try not to split consecutive data keys */ + appending = 0; +check_split: + if (n >= (c->fanout + 1) / 2) { + key1 = &znode->zbranch[0].key; + if (key_inum(c, key1) == key_inum(c, key) && + key_type(c, key1) == UBIFS_DATA_KEY) { + key1 = &znode->zbranch[n].key; + if (key_inum(c, key1) != key_inum(c, key) || + key_type(c, key1) != UBIFS_DATA_KEY) { + keep = n; + move = c->fanout - keep; + zi = znode; + goto do_split; + } + } + } + } + + if (appending) { + keep = c->fanout; + move = 0; + } else { + keep = (c->fanout + 1) / 2; + move = c->fanout - keep; + } + + /* + * Although we don't at present, we could look at the neighbors and see + * if we can move some zbranches there. + */ + + if (n < keep) { + /* Insert into existing znode */ + zi = znode; + move += 1; + keep -= 1; + } else { + /* Insert into new znode */ + zi = zn; + n -= keep; + /* Re-parent */ + if (zn->level != 0) + zbr->znode->parent = zn; + } + +do_split: + + __set_bit(DIRTY_ZNODE, &zn->flags); + atomic_long_inc(&c->dirty_zn_cnt); + + zn->child_cnt = move; + znode->child_cnt = keep; + + dbg_tnc("moving %d, keeping %d", move, keep); + + /* Move zbranch */ + for (i = 0; i < move; i++) { + zn->zbranch[i] = znode->zbranch[keep + i]; + /* Re-parent */ + if (zn->level != 0) + if (zn->zbranch[i].znode) { + zn->zbranch[i].znode->parent = zn; + zn->zbranch[i].znode->iip = i; + } + } + + /* Insert new key and branch */ + dbg_tnck(key, "inserting at %d level %d, key ", n, zn->level); + + insert_zbranch(c, zi, zbr, n); + + /* Insert new znode (produced by spitting) into the parent */ + if (zp) { + if (n == 0 && zi == znode && znode->iip == 0) + correct_parent_keys(c, znode); + + /* Locate insertion point */ + n = znode->iip + 1; + + /* Tail recursion */ + zbr->key = zn->zbranch[0].key; + zbr->znode = zn; + zbr->lnum = 0; + zbr->offs = 0; + zbr->len = 0; + znode = zp; + + goto again; + } + + /* We have to split root znode */ + dbg_tnc("creating new zroot at level %d", znode->level + 1); + + zi = kzalloc(c->max_znode_sz, GFP_NOFS); + if (!zi) + return -ENOMEM; + + zi->child_cnt = 2; + zi->level = znode->level + 1; + + __set_bit(DIRTY_ZNODE, &zi->flags); + atomic_long_inc(&c->dirty_zn_cnt); + + zi->zbranch[0].key = znode->zbranch[0].key; + zi->zbranch[0].znode = znode; + zi->zbranch[0].lnum = c->zroot.lnum; + zi->zbranch[0].offs = c->zroot.offs; + zi->zbranch[0].len = c->zroot.len; + zi->zbranch[1].key = zn->zbranch[0].key; + zi->zbranch[1].znode = zn; + + c->zroot.lnum = 0; + c->zroot.offs = 0; + c->zroot.len = 0; + c->zroot.znode = zi; + + zn->parent = zi; + zn->iip = 1; + znode->parent = zi; + znode->iip = 0; + + return 0; +} + +/** + * ubifs_tnc_add - add a node to TNC. + * @c: UBIFS file-system description object + * @key: key to add + * @lnum: LEB number of node + * @offs: node offset + * @len: node length + * @hash: The hash over the node + * + * This function adds a node with key @key to TNC. The node may be new or it may + * obsolete some existing one. Returns %0 on success or negative error code on + * failure. + */ +int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum, + int offs, int len, const u8 *hash) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnck(key, "%d:%d, len %d, key ", lnum, offs, len); + found = lookup_level0_dirty(c, key, &znode, &n); + if (!found) { + struct ubifs_zbranch zbr; + + zbr.znode = NULL; + zbr.lnum = lnum; + zbr.offs = offs; + zbr.len = len; + ubifs_copy_hash(c, hash, zbr.hash); + key_copy(c, key, &zbr.key); + err = tnc_insert(c, znode, &zbr, n + 1); + } else if (found == 1) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + ubifs_copy_hash(c, hash, zbr->hash); + } else + err = found; + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + + return err; +} + +/** + * ubifs_tnc_replace - replace a node in the TNC only if the old node is found. + * @c: UBIFS file-system description object + * @key: key to add + * @old_lnum: LEB number of old node + * @old_offs: old node offset + * @lnum: LEB number of node + * @offs: node offset + * @len: node length + * + * This function replaces a node with key @key in the TNC only if the old node + * is found. This function is called by garbage collection when node are moved. + * Returns %0 on success or negative error code on failure. + */ +int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key, + int old_lnum, int old_offs, int lnum, int offs, int len) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnck(key, "old LEB %d:%d, new LEB %d:%d, len %d, key ", old_lnum, + old_offs, lnum, offs, len); + found = lookup_level0_dirty(c, key, &znode, &n); + if (found < 0) { + err = found; + goto out_unlock; + } + + if (found == 1) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + found = 0; + if (zbr->lnum == old_lnum && zbr->offs == old_offs) { + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + if (err) + goto out_unlock; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + found = 1; + } else if (is_hash_key(c, key)) { + found = resolve_collision_directly(c, key, &znode, &n, + old_lnum, old_offs); + dbg_tnc("rc returned %d, znode %p, n %d, LEB %d:%d", + found, znode, n, old_lnum, old_offs); + if (found < 0) { + err = found; + goto out_unlock; + } + + if (found) { + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + zbr = &znode->zbranch[n]; + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, + zbr->len); + if (err) + goto out_unlock; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + } + } + } + + if (!found) + err = ubifs_add_dirt(c, lnum, len); + + if (!err) + err = dbg_check_tnc(c, 0); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_add_nm - add a "hashed" node to TNC. + * @c: UBIFS file-system description object + * @key: key to add + * @lnum: LEB number of node + * @offs: node offset + * @len: node length + * @hash: The hash over the node + * @nm: node name + * + * This is the same as 'ubifs_tnc_add()' but it should be used with keys which + * may have collisions, like directory entry keys. + */ +int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key, + int lnum, int offs, int len, const u8 *hash, + const struct fscrypt_name *nm) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnck(key, "LEB %d:%d, key ", lnum, offs); + found = lookup_level0_dirty(c, key, &znode, &n); + if (found < 0) { + err = found; + goto out_unlock; + } + + if (found == 1) { + if (c->replaying) + found = fallible_resolve_collision(c, key, &znode, &n, + nm, 1); + else + found = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", found, znode, n); + if (found < 0) { + err = found; + goto out_unlock; + } + + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + + if (found == 1) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + ubifs_copy_hash(c, hash, zbr->hash); + goto out_unlock; + } + } + + if (!found) { + struct ubifs_zbranch zbr; + + zbr.znode = NULL; + zbr.lnum = lnum; + zbr.offs = offs; + zbr.len = len; + ubifs_copy_hash(c, hash, zbr.hash); + key_copy(c, key, &zbr.key); + err = tnc_insert(c, znode, &zbr, n + 1); + if (err) + goto out_unlock; + if (c->replaying) { + /* + * We did not find it in the index so there may be a + * dangling branch still in the index. So we remove it + * by passing 'ubifs_tnc_remove_nm()' the same key but + * an unmatchable name. + */ + struct fscrypt_name noname = { .disk_name = { .name = "", .len = 1 } }; + + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + if (err) + return err; + return ubifs_tnc_remove_nm(c, key, &noname); + } + } + +out_unlock: + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * tnc_delete - delete a znode form TNC. + * @c: UBIFS file-system description object + * @znode: znode to delete from + * @n: zbranch slot number to delete + * + * This function deletes a leaf node from @n-th slot of @znode. Returns zero in + * case of success and a negative error code in case of failure. + */ +static int tnc_delete(struct ubifs_info *c, struct ubifs_znode *znode, int n) +{ + struct ubifs_zbranch *zbr; + struct ubifs_znode *zp; + int i, err; + + /* Delete without merge for now */ + ubifs_assert(c, znode->level == 0); + ubifs_assert(c, n >= 0 && n < c->fanout); + dbg_tnck(&znode->zbranch[n].key, "deleting key "); + + zbr = &znode->zbranch[n]; + lnc_free(zbr); + + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + if (err) { + ubifs_dump_znode(c, znode); + return err; + } + + /* We do not "gap" zbranch slots */ + for (i = n; i < znode->child_cnt - 1; i++) + znode->zbranch[i] = znode->zbranch[i + 1]; + znode->child_cnt -= 1; + + if (znode->child_cnt > 0) + return 0; + + /* Different with linux kernel, TNC could become empty. */ + if (!znode->parent) + return 0; + + /* + * This was the last zbranch, we have to delete this znode from the + * parent. + */ + + do { + ubifs_assert(c, !ubifs_zn_obsolete(znode)); + ubifs_assert(c, ubifs_zn_dirty(znode)); + + zp = znode->parent; + n = znode->iip; + + atomic_long_dec(&c->dirty_zn_cnt); + + err = insert_old_idx_znode(c, znode); + if (err) + return err; + + if (znode->cnext) { + __set_bit(OBSOLETE_ZNODE, &znode->flags); + atomic_long_inc(&c->clean_zn_cnt); + atomic_long_inc(&ubifs_clean_zn_cnt); + } else + kfree(znode); + znode = zp; + } while (znode->child_cnt == 1); /* while removing last child */ + + /* Remove from znode, entry n - 1 */ + znode->child_cnt -= 1; + ubifs_assert(c, znode->level != 0); + for (i = n; i < znode->child_cnt; i++) { + znode->zbranch[i] = znode->zbranch[i + 1]; + if (znode->zbranch[i].znode) + znode->zbranch[i].znode->iip = i; + } + + /* + * If this is the root and it has only 1 child then + * collapse the tree. + */ + if (!znode->parent) { + while (znode->child_cnt == 1 && znode->level != 0) { + zp = znode; + zbr = &znode->zbranch[0]; + znode = get_znode(c, znode, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + znode = dirty_cow_znode(c, zbr); + if (IS_ERR(znode)) + return PTR_ERR(znode); + znode->parent = NULL; + znode->iip = 0; + if (c->zroot.len) { + err = insert_old_idx(c, c->zroot.lnum, + c->zroot.offs); + if (err) + return err; + } + c->zroot.lnum = zbr->lnum; + c->zroot.offs = zbr->offs; + c->zroot.len = zbr->len; + c->zroot.znode = znode; + ubifs_assert(c, !ubifs_zn_obsolete(zp)); + ubifs_assert(c, ubifs_zn_dirty(zp)); + atomic_long_dec(&c->dirty_zn_cnt); + + if (zp->cnext) { + __set_bit(OBSOLETE_ZNODE, &zp->flags); + atomic_long_inc(&c->clean_zn_cnt); + atomic_long_inc(&ubifs_clean_zn_cnt); + } else + kfree(zp); + } + } + + return 0; +} + +/** + * ubifs_tnc_remove - remove an index entry of a node. + * @c: UBIFS file-system description object + * @key: key of node + * + * Returns %0 on success or negative error code on failure. + */ +int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnck(key, "key "); + found = lookup_level0_dirty(c, key, &znode, &n); + if (found < 0) { + err = found; + goto out_unlock; + } + if (found == 1) + err = tnc_delete(c, znode, n); + if (!err) + err = dbg_check_tnc(c, 0); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_remove_nm - remove an index entry for a "hashed" node. + * @c: UBIFS file-system description object + * @key: key of node + * @nm: directory entry name + * + * Returns %0 on success or negative error code on failure. + */ +int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key, + const struct fscrypt_name *nm) +{ + int n, err; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnck(key, "key "); + err = lookup_level0_dirty(c, key, &znode, &n); + if (err < 0) + goto out_unlock; + + if (err) { + if (c->replaying) + err = fallible_resolve_collision(c, key, &znode, &n, + nm, 0); + else + err = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n); + if (err < 0) + goto out_unlock; + if (err) { + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + err = tnc_delete(c, znode, n); + } + } + +out_unlock: + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * key_in_range - determine if a key falls within a range of keys. + * @c: UBIFS file-system description object + * @key: key to check + * @from_key: lowest key in range + * @to_key: highest key in range + * + * This function returns %1 if the key is in range and %0 otherwise. + */ +static int key_in_range(struct ubifs_info *c, union ubifs_key *key, + union ubifs_key *from_key, union ubifs_key *to_key) +{ + if (keys_cmp(c, key, from_key) < 0) + return 0; + if (keys_cmp(c, key, to_key) > 0) + return 0; + return 1; +} + +/** + * ubifs_tnc_remove_range - remove index entries in range. + * @c: UBIFS file-system description object + * @from_key: lowest key to remove + * @to_key: highest key to remove + * + * This function removes index entries starting at @from_key and ending at + * @to_key. This function returns zero in case of success and a negative error + * code in case of failure. + */ +int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key, + union ubifs_key *to_key) +{ + int i, n, k, err = 0; + struct ubifs_znode *znode; + union ubifs_key *key; + + mutex_lock(&c->tnc_mutex); + while (1) { + /* Find first level 0 znode that contains keys to remove */ + err = ubifs_lookup_level0(c, from_key, &znode, &n); + if (err < 0) + goto out_unlock; + + if (err) + key = from_key; + else { + err = tnc_next(c, &znode, &n); + if (err == -ENOENT) { + err = 0; + goto out_unlock; + } + if (err < 0) + goto out_unlock; + key = &znode->zbranch[n].key; + if (!key_in_range(c, key, from_key, to_key)) { + err = 0; + goto out_unlock; + } + } + + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + + /* Remove all keys in range except the first */ + for (i = n + 1, k = 0; i < znode->child_cnt; i++, k++) { + key = &znode->zbranch[i].key; + if (!key_in_range(c, key, from_key, to_key)) + break; + lnc_free(&znode->zbranch[i]); + err = ubifs_add_dirt(c, znode->zbranch[i].lnum, + znode->zbranch[i].len); + if (err) { + ubifs_dump_znode(c, znode); + goto out_unlock; + } + dbg_tnck(key, "removing key "); + } + if (k) { + for (i = n + 1 + k; i < znode->child_cnt; i++) + znode->zbranch[i - k] = znode->zbranch[i]; + znode->child_cnt -= k; + } + + /* Now delete the first */ + err = tnc_delete(c, znode, n); + if (err) + goto out_unlock; + } + +out_unlock: + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_remove_ino - remove an inode from TNC. + * @c: UBIFS file-system description object + * @inum: inode number to remove + * + * This function remove inode @inum and all the extended attributes associated + * with the anode from TNC and returns zero in case of success or a negative + * error code in case of failure. + */ +int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum) +{ + union ubifs_key key1, key2; + struct ubifs_dent_node *xent, *pxent = NULL; + struct fscrypt_name nm = {0}; + + dbg_tnc("ino %lu", (unsigned long)inum); + + /* + * Walk all extended attribute entries and remove them together with + * corresponding extended attribute inodes. + */ + lowest_xent_key(c, &key1, inum); + while (1) { + ino_t xattr_inum; + int err; + + xent = ubifs_tnc_next_ent(c, &key1, &nm); + if (IS_ERR(xent)) { + unsigned int reason; + + err = PTR_ERR(xent); + if (err == -ENOENT) + break; + + reason = get_failure_reason_callback(c); + if (reason & FR_DATA_CORRUPTED) { + test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED); + if (handle_failure_callback(c, FR_H_TNC_DATA_CORRUPTED, NULL)) { + /* Set %FR_LPT_INCORRECT for lpt status. */ + set_lpt_invalid_callback(c, FR_LPT_INCORRECT); + /* Leave xattrs to be deleted by subsequent steps */ + break; + } + } + kfree(pxent); + return err; + } + + xattr_inum = le64_to_cpu(xent->inum); + dbg_tnc("xent '%s', ino %lu", xent->name, + (unsigned long)xattr_inum); + + fname_name(&nm) = (const char *)xent->name; + fname_len(&nm) = le16_to_cpu(xent->nlen); + err = ubifs_tnc_remove_nm(c, &key1, &nm); + if (err) { + kfree(pxent); + kfree(xent); + return err; + } + + lowest_ino_key(c, &key1, xattr_inum); + highest_ino_key(c, &key2, xattr_inum); + err = ubifs_tnc_remove_range(c, &key1, &key2); + if (err) { + kfree(pxent); + kfree(xent); + return err; + } + + kfree(pxent); + pxent = xent; + key_read(c, &xent->key, &key1); + } + + kfree(pxent); + lowest_ino_key(c, &key1, inum); + highest_ino_key(c, &key2, inum); + + return ubifs_tnc_remove_range(c, &key1, &key2); +} + +/** + * ubifs_tnc_remove_node - remove an index entry of a node by given position. + * @c: UBIFS file-system description object + * @key: key of node + * @lnum: LEB number of node + * @offs: node offset + * + * Returns %0 on success or negative error code on failure. + */ +int ubifs_tnc_remove_node(struct ubifs_info *c, const union ubifs_key *key, + int lnum, int offs) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnck(key, "pos %d:%d, key ", lnum, offs); + found = lookup_level0_dirty(c, key, &znode, &n); + if (found < 0) { + err = found; + goto out_unlock; + } + if (found == 1) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + if (zbr->lnum == lnum && zbr->offs == offs) { + err = tnc_delete(c, znode, n); + } else if (is_hash_key(c, key)) { + found = resolve_collision_directly(c, key, &znode, &n, + lnum, offs); + if (found < 0) { + err = found; + goto out_unlock; + } + + if (found) { + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + err = tnc_delete(c, znode, n); + } else { + goto not_found; + } + } else { + goto not_found; + } + } else { +not_found: + /* Impossible, the node has been found before being deleted. */ + ubifs_assert(c, 0); + } + if (!err) + err = dbg_check_tnc(c, 0); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_next_ent - walk directory or extended attribute entries. + * @c: UBIFS file-system description object + * @key: key of last entry + * @nm: name of last entry found or %NULL + * + * This function finds and reads the next directory or extended attribute entry + * after the given key (@key) if there is one. @nm is used to resolve + * collisions. + * + * If the name of the current entry is not known and only the key is known, + * @nm->name has to be %NULL. In this case the semantics of this function is a + * little bit different and it returns the entry corresponding to this key, not + * the next one. If the key was not found, the closest "right" entry is + * returned. + * + * If the fist entry has to be found, @key has to contain the lowest possible + * key value for this inode and @name has to be %NULL. + * + * This function returns the found directory or extended attribute entry node + * in case of success, %-ENOENT is returned if no entry was found, and a + * negative error code is returned in case of failure. + */ +struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c, + union ubifs_key *key, + const struct fscrypt_name *nm) +{ + int n, err, type = key_type(c, key); + struct ubifs_znode *znode; + struct ubifs_dent_node *dent; + struct ubifs_zbranch *zbr; + union ubifs_key *dkey; + + dbg_tnck(key, "key "); + ubifs_assert(c, is_hash_key(c, key)); + + mutex_lock(&c->tnc_mutex); + err = ubifs_lookup_level0(c, key, &znode, &n); + if (unlikely(err < 0)) + goto out_unlock; + + if (fname_len(nm) > 0) { + if (err) { + /* Handle collisions */ + if (c->replaying) + err = fallible_resolve_collision(c, key, &znode, &n, + nm, 0); + else + err = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", + err, znode, n); + if (unlikely(err < 0)) + goto out_unlock; + } + + /* Now find next entry */ + err = tnc_next(c, &znode, &n); + if (unlikely(err)) + goto out_unlock; + } else { + /* + * The full name of the entry was not given, in which case the + * behavior of this function is a little different and it + * returns current entry, not the next one. + */ + if (!err) { + /* + * However, the given key does not exist in the TNC + * tree and @znode/@n variables contain the closest + * "preceding" element. Switch to the next one. + */ + err = tnc_next(c, &znode, &n); + if (err) + goto out_unlock; + } + } + + zbr = &znode->zbranch[n]; + dent = kmalloc(zbr->len, GFP_NOFS); + if (unlikely(!dent)) { + err = -ENOMEM; + goto out_unlock; + } + + /* + * The above 'tnc_next()' call could lead us to the next inode, check + * this. + */ + dkey = &zbr->key; + if (key_inum(c, dkey) != key_inum(c, key) || + key_type(c, dkey) != type) { + err = -ENOENT; + goto out_free; + } + + err = tnc_read_hashed_node(c, zbr, dent); + if (unlikely(err)) + goto out_free; + + mutex_unlock(&c->tnc_mutex); + return dent; + +out_free: + kfree(dent); +out_unlock: + mutex_unlock(&c->tnc_mutex); + return ERR_PTR(err); +} + +/** + * tnc_destroy_cnext - destroy left-over obsolete znodes from a failed commit. + * @c: UBIFS file-system description object + * + * Destroy left-over obsolete znodes from a failed commit. + */ +static void tnc_destroy_cnext(struct ubifs_info *c) +{ + struct ubifs_znode *cnext; + + if (!c->cnext) + return; + ubifs_assert(c, c->cmt_state == COMMIT_BROKEN); + cnext = c->cnext; + do { + struct ubifs_znode *znode = cnext; + + cnext = cnext->cnext; + if (ubifs_zn_obsolete(znode)) + kfree(znode); + else if (!ubifs_zn_cow(znode)) { + /* + * Don't forget to update clean znode count after + * committing failed, because ubifs will check this + * count while closing tnc. Non-obsolete znode could + * be re-dirtied during committing process, so dirty + * flag is untrustable. The flag 'COW_ZNODE' is set + * for each dirty znode before committing, and it is + * cleared as long as the znode become clean, so we + * can statistic clean znode count according to this + * flag. + */ + atomic_long_inc(&c->clean_zn_cnt); + atomic_long_inc(&ubifs_clean_zn_cnt); + } + } while (cnext && cnext != c->cnext); +} + +/** + * ubifs_tnc_close - close TNC subsystem and free all related resources. + * @c: UBIFS file-system description object + */ +void ubifs_tnc_close(struct ubifs_info *c) +{ + tnc_destroy_cnext(c); + ubifs_destroy_tnc_tree(c); + kfree(c->gap_lebs); + kfree(c->ilebs); + destroy_old_idx(c); +} + +/** + * left_znode - get the znode to the left. + * @c: UBIFS file-system description object + * @znode: znode + * + * This function returns a pointer to the znode to the left of @znode or NULL if + * there is not one. A negative error code is returned on failure. + */ +static struct ubifs_znode *left_znode(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + int level = znode->level; + + while (1) { + int n = znode->iip - 1; + + /* Go up until we can go left */ + znode = znode->parent; + if (!znode) + return NULL; + if (n >= 0) { + /* Now go down the rightmost branch to 'level' */ + znode = get_znode(c, znode, n); + if (IS_ERR(znode)) + return znode; + while (znode->level != level) { + n = znode->child_cnt - 1; + znode = get_znode(c, znode, n); + if (IS_ERR(znode)) + return znode; + } + break; + } + } + return znode; +} + +/** + * right_znode - get the znode to the right. + * @c: UBIFS file-system description object + * @znode: znode + * + * This function returns a pointer to the znode to the right of @znode or NULL + * if there is not one. A negative error code is returned on failure. + */ +static struct ubifs_znode *right_znode(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + int level = znode->level; + + while (1) { + int n = znode->iip + 1; + + /* Go up until we can go right */ + znode = znode->parent; + if (!znode) + return NULL; + if (n < znode->child_cnt) { + /* Now go down the leftmost branch to 'level' */ + znode = get_znode(c, znode, n); + if (IS_ERR(znode)) + return znode; + while (znode->level != level) { + znode = get_znode(c, znode, 0); + if (IS_ERR(znode)) + return znode; + } + break; + } + } + return znode; +} + +/** + * lookup_znode - find a particular indexing node from TNC. + * @c: UBIFS file-system description object + * @key: index node key to lookup + * @level: index node level + * @lnum: index node LEB number + * @offs: index node offset + * + * This function searches an indexing node by its first key @key and its + * address @lnum:@offs. It looks up the indexing tree by pulling all indexing + * nodes it traverses to TNC. This function is called for indexing nodes which + * were found on the media by scanning, for example when garbage-collecting or + * when doing in-the-gaps commit. This means that the indexing node which is + * looked for does not have to have exactly the same leftmost key @key, because + * the leftmost key may have been changed, in which case TNC will contain a + * dirty znode which still refers the same @lnum:@offs. This function is clever + * enough to recognize such indexing nodes. + * + * Note, if a znode was deleted or changed too much, then this function will + * not find it. For situations like this UBIFS has the old index RB-tree + * (indexed by @lnum:@offs). + * + * This function returns a pointer to the znode found or %NULL if it is not + * found. A negative error code is returned on failure. + */ +static struct ubifs_znode *lookup_znode(struct ubifs_info *c, + union ubifs_key *key, int level, + int lnum, int offs) +{ + struct ubifs_znode *znode, *zn; + int n, nn; + + ubifs_assert(c, key_type(c, key) < UBIFS_INVALID_KEY); + + /* + * The arguments have probably been read off flash, so don't assume + * they are valid. + */ + if (level < 0) + return ERR_PTR(-EINVAL); + + /* Get the root znode */ + znode = c->zroot.znode; + if (!znode) { + znode = ubifs_load_znode(c, &c->zroot, NULL, 0); + if (IS_ERR(znode)) + return znode; + } + /* Check if it is the one we are looking for */ + if (c->zroot.lnum == lnum && c->zroot.offs == offs) + return znode; + /* Descend to the parent level i.e. (level + 1) */ + if (level >= znode->level) + return NULL; + while (1) { + ubifs_search_zbranch(c, znode, key, &n); + if (n < 0) { + /* + * We reached a znode where the leftmost key is greater + * than the key we are searching for. This is the same + * situation as the one described in a huge comment at + * the end of the 'ubifs_lookup_level0()' function. And + * for exactly the same reasons we have to try to look + * left before giving up. + */ + znode = left_znode(c, znode); + if (!znode) + return NULL; + if (IS_ERR(znode)) + return znode; + ubifs_search_zbranch(c, znode, key, &n); + ubifs_assert(c, n >= 0); + } + if (znode->level == level + 1) + break; + znode = get_znode(c, znode, n); + if (IS_ERR(znode)) + return znode; + } + /* Check if the child is the one we are looking for */ + if (znode->zbranch[n].lnum == lnum && znode->zbranch[n].offs == offs) + return get_znode(c, znode, n); + /* If the key is unique, there is nowhere else to look */ + if (!is_hash_key(c, key)) + return NULL; + /* + * The key is not unique and so may be also in the znodes to either + * side. + */ + zn = znode; + nn = n; + /* Look left */ + while (1) { + /* Move one branch to the left */ + if (n) + n -= 1; + else { + znode = left_znode(c, znode); + if (!znode) + break; + if (IS_ERR(znode)) + return znode; + n = znode->child_cnt - 1; + } + /* Check it */ + if (znode->zbranch[n].lnum == lnum && + znode->zbranch[n].offs == offs) + return get_znode(c, znode, n); + /* Stop if the key is less than the one we are looking for */ + if (keys_cmp(c, &znode->zbranch[n].key, key) < 0) + break; + } + /* Back to the middle */ + znode = zn; + n = nn; + /* Look right */ + while (1) { + /* Move one branch to the right */ + if (++n >= znode->child_cnt) { + znode = right_znode(c, znode); + if (!znode) + break; + if (IS_ERR(znode)) + return znode; + n = 0; + } + /* Check it */ + if (znode->zbranch[n].lnum == lnum && + znode->zbranch[n].offs == offs) + return get_znode(c, znode, n); + /* Stop if the key is greater than the one we are looking for */ + if (keys_cmp(c, &znode->zbranch[n].key, key) > 0) + break; + } + return NULL; +} + +/** + * is_idx_node_in_tnc - determine if an index node is in the TNC. + * @c: UBIFS file-system description object + * @key: key of index node + * @level: index node level + * @lnum: LEB number of index node + * @offs: offset of index node + * + * This function returns %0 if the index node is not referred to in the TNC, %1 + * if the index node is referred to in the TNC and the corresponding znode is + * dirty, %2 if an index node is referred to in the TNC and the corresponding + * znode is clean, and a negative error code in case of failure. + * + * Note, the @key argument has to be the key of the first child. Also note, + * this function relies on the fact that 0:0 is never a valid LEB number and + * offset for a main-area node. + */ +int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs) +{ + struct ubifs_znode *znode; + + znode = lookup_znode(c, key, level, lnum, offs); + if (!znode) + return 0; + if (IS_ERR(znode)) + return PTR_ERR(znode); + + return ubifs_zn_dirty(znode) ? 1 : 2; +} + +/** + * is_leaf_node_in_tnc - determine if a non-indexing not is in the TNC. + * @c: UBIFS file-system description object + * @key: node key + * @lnum: node LEB number + * @offs: node offset + * + * This function returns %1 if the node is referred to in the TNC, %0 if it is + * not, and a negative error code in case of failure. + * + * Note, this function relies on the fact that 0:0 is never a valid LEB number + * and offset for a main-area node. + */ +static int is_leaf_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, + int lnum, int offs) +{ + struct ubifs_zbranch *zbr; + struct ubifs_znode *znode, *zn; + int n, found, err, nn; + const int unique = !is_hash_key(c, key); + + found = ubifs_lookup_level0(c, key, &znode, &n); + if (found < 0) + return found; /* Error code */ + if (!found) + return 0; + zbr = &znode->zbranch[n]; + if (lnum == zbr->lnum && offs == zbr->offs) + return 1; /* Found it */ + if (unique) + return 0; + /* + * Because the key is not unique, we have to look left + * and right as well + */ + zn = znode; + nn = n; + /* Look left */ + while (1) { + err = tnc_prev(c, &znode, &n); + if (err == -ENOENT) + break; + if (err) + return err; + if (keys_cmp(c, key, &znode->zbranch[n].key)) + break; + zbr = &znode->zbranch[n]; + if (lnum == zbr->lnum && offs == zbr->offs) + return 1; /* Found it */ + } + /* Look right */ + znode = zn; + n = nn; + while (1) { + err = tnc_next(c, &znode, &n); + if (err) { + if (err == -ENOENT) + return 0; + return err; + } + if (keys_cmp(c, key, &znode->zbranch[n].key)) + break; + zbr = &znode->zbranch[n]; + if (lnum == zbr->lnum && offs == zbr->offs) + return 1; /* Found it */ + } + return 0; +} + +/** + * ubifs_tnc_has_node - determine whether a node is in the TNC. + * @c: UBIFS file-system description object + * @key: node key + * @level: index node level (if it is an index node) + * @lnum: node LEB number + * @offs: node offset + * @is_idx: non-zero if the node is an index node + * + * This function returns %1 if the node is in the TNC, %0 if it is not, and a + * negative error code in case of failure. For index nodes, @key has to be the + * key of the first child. An index node is considered to be in the TNC only if + * the corresponding znode is clean or has not been loaded. + */ +int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs, int is_idx) +{ + int err; + + mutex_lock(&c->tnc_mutex); + if (is_idx) { + err = is_idx_node_in_tnc(c, key, level, lnum, offs); + if (err < 0) + goto out_unlock; + if (err == 1) + /* The index node was found but it was dirty */ + err = 0; + else if (err == 2) + /* The index node was found and it was clean */ + err = 1; + else + BUG_ON(err != 0); + } else + err = is_leaf_node_in_tnc(c, key, lnum, offs); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_dirty_idx_node - dirty an index node. + * @c: UBIFS file-system description object + * @key: index node key + * @level: index node level + * @lnum: index node LEB number + * @offs: index node offset + * + * This function loads and dirties an index node so that it can be garbage + * collected. The @key argument has to be the key of the first child. This + * function relies on the fact that 0:0 is never a valid LEB number and offset + * for a main-area node. Returns %0 on success and a negative error code on + * failure. + */ +int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs) +{ + struct ubifs_znode *znode; + int err = 0; + + mutex_lock(&c->tnc_mutex); + znode = lookup_znode(c, key, level, lnum, offs); + if (!znode) + goto out_unlock; + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} diff --git a/ubifs-utils/libubifs/tnc_commit.c b/ubifs-utils/libubifs/tnc_commit.c new file mode 100644 index 0000000..66922d4 --- /dev/null +++ b/ubifs-utils/libubifs/tnc_commit.c @@ -0,0 +1,1119 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* This file implements TNC functions for committing */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/** + * make_idx_node - make an index node for fill-the-gaps method of TNC commit. + * @c: UBIFS file-system description object + * @idx: buffer in which to place new index node + * @znode: znode from which to make new index node + * @lnum: LEB number where new index node will be written + * @offs: offset where new index node will be written + * @len: length of new index node + */ +static int make_idx_node(struct ubifs_info *c, struct ubifs_idx_node *idx, + struct ubifs_znode *znode, int lnum, int offs, int len) +{ + struct ubifs_znode *zp; + u8 hash[UBIFS_HASH_ARR_SZ]; + int i, err; + + /* Make index node */ + idx->ch.node_type = UBIFS_IDX_NODE; + idx->child_cnt = cpu_to_le16(znode->child_cnt); + idx->level = cpu_to_le16(znode->level); + for (i = 0; i < znode->child_cnt; i++) { + struct ubifs_branch *br = ubifs_idx_branch(c, idx, i); + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + key_write_idx(c, &zbr->key, &br->key); + br->lnum = cpu_to_le32(zbr->lnum); + br->offs = cpu_to_le32(zbr->offs); + br->len = cpu_to_le32(zbr->len); + ubifs_copy_hash(c, zbr->hash, ubifs_branch_hash(c, br)); + if (!zbr->lnum || !zbr->len) { + ubifs_err(c, "bad ref in znode"); + ubifs_dump_znode(c, znode); + if (zbr->znode) + ubifs_dump_znode(c, zbr->znode); + + return -EINVAL; + } + } + ubifs_prepare_node(c, idx, len, 0); + ubifs_node_calc_hash(c, idx, hash); + + znode->lnum = lnum; + znode->offs = offs; + znode->len = len; + + err = insert_old_idx_znode(c, znode); + + /* Update the parent */ + zp = znode->parent; + if (zp) { + struct ubifs_zbranch *zbr; + + zbr = &zp->zbranch[znode->iip]; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + ubifs_copy_hash(c, hash, zbr->hash); + } else { + c->zroot.lnum = lnum; + c->zroot.offs = offs; + c->zroot.len = len; + ubifs_copy_hash(c, hash, c->zroot.hash); + } + c->calc_idx_sz += ALIGN(len, 8); + + atomic_long_dec(&c->dirty_zn_cnt); + + ubifs_assert(c, ubifs_zn_dirty(znode)); + ubifs_assert(c, ubifs_zn_cow(znode)); + + /* + * Note, unlike 'write_index()' we do not add memory barriers here + * because this function is called with @c->tnc_mutex locked. + */ + __clear_bit(DIRTY_ZNODE, &znode->flags); + __clear_bit(COW_ZNODE, &znode->flags); + + return err; +} + +/** + * fill_gap - make index nodes in gaps in dirty index LEBs. + * @c: UBIFS file-system description object + * @lnum: LEB number that gap appears in + * @gap_start: offset of start of gap + * @gap_end: offset of end of gap + * @dirt: adds dirty space to this + * + * This function returns the number of index nodes written into the gap. + */ +static int fill_gap(struct ubifs_info *c, int lnum, int gap_start, int gap_end, + int *dirt) +{ + int len, gap_remains, gap_pos, written, pad_len; + + ubifs_assert(c, (gap_start & 7) == 0); + ubifs_assert(c, (gap_end & 7) == 0); + ubifs_assert(c, gap_end >= gap_start); + + gap_remains = gap_end - gap_start; + if (!gap_remains) + return 0; + gap_pos = gap_start; + written = 0; + while (c->enext) { + len = ubifs_idx_node_sz(c, c->enext->child_cnt); + if (len < gap_remains) { + struct ubifs_znode *znode = c->enext; + const int alen = ALIGN(len, 8); + int err; + + ubifs_assert(c, alen <= gap_remains); + err = make_idx_node(c, c->ileb_buf + gap_pos, znode, + lnum, gap_pos, len); + if (err) + return err; + gap_remains -= alen; + gap_pos += alen; + c->enext = znode->cnext; + if (c->enext == c->cnext) + c->enext = NULL; + written += 1; + } else + break; + } + if (gap_end == c->leb_size) { + c->ileb_len = ALIGN(gap_pos, c->min_io_size); + /* Pad to end of min_io_size */ + pad_len = c->ileb_len - gap_pos; + } else + /* Pad to end of gap */ + pad_len = gap_remains; + dbg_gc("LEB %d:%d to %d len %d nodes written %d wasted bytes %d", + lnum, gap_start, gap_end, gap_end - gap_start, written, pad_len); + ubifs_pad(c, c->ileb_buf + gap_pos, pad_len); + *dirt += pad_len; + return written; +} + +/** + * find_old_idx - find an index node obsoleted since the last commit start. + * @c: UBIFS file-system description object + * @lnum: LEB number of obsoleted index node + * @offs: offset of obsoleted index node + * + * Returns %1 if found and %0 otherwise. + */ +static int find_old_idx(struct ubifs_info *c, int lnum, int offs) +{ + struct ubifs_old_idx *o; + struct rb_node *p; + + p = c->old_idx.rb_node; + while (p) { + o = rb_entry(p, struct ubifs_old_idx, rb); + if (lnum < o->lnum) + p = p->rb_left; + else if (lnum > o->lnum) + p = p->rb_right; + else if (offs < o->offs) + p = p->rb_left; + else if (offs > o->offs) + p = p->rb_right; + else + return 1; + } + return 0; +} + +/** + * is_idx_node_in_use - determine if an index node can be overwritten. + * @c: UBIFS file-system description object + * @key: key of index node + * @level: index node level + * @lnum: LEB number of index node + * @offs: offset of index node + * + * If @key / @lnum / @offs identify an index node that was not part of the old + * index, then this function returns %0 (obsolete). Else if the index node was + * part of the old index but is now dirty %1 is returned, else if it is clean %2 + * is returned. A negative error code is returned on failure. + */ +static int is_idx_node_in_use(struct ubifs_info *c, union ubifs_key *key, + int level, int lnum, int offs) +{ + int ret; + + ret = is_idx_node_in_tnc(c, key, level, lnum, offs); + if (ret < 0) + return ret; /* Error code */ + if (ret == 0) + if (find_old_idx(c, lnum, offs)) + return 1; + return ret; +} + +/** + * layout_leb_in_gaps - layout index nodes using in-the-gaps method. + * @c: UBIFS file-system description object + * @p: return LEB number in @c->gap_lebs[p] + * + * This function lays out new index nodes for dirty znodes using in-the-gaps + * method of TNC commit. + * This function merely puts the next znode into the next gap, making no attempt + * to try to maximise the number of znodes that fit. + * This function returns the number of index nodes written into the gaps, or a + * negative error code on failure. + */ +static int layout_leb_in_gaps(struct ubifs_info *c, int p) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + int lnum, dirt = 0, gap_start, gap_end, err, written, tot_written; + + tot_written = 0; + /* Get an index LEB with lots of obsolete index nodes */ + lnum = ubifs_find_dirty_idx_leb(c); + if (lnum < 0) + /* + * There also may be dirt in the index head that could be + * filled, however we do not check there at present. + */ + return lnum; /* Error code */ + c->gap_lebs[p] = lnum; + dbg_gc("LEB %d", lnum); + /* + * Scan the index LEB. We use the generic scan for this even though + * it is more comprehensive and less efficient than is needed for this + * purpose. + */ + sleb = ubifs_scan(c, lnum, 0, c->ileb_buf, 0); + c->ileb_len = 0; + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + gap_start = 0; + list_for_each_entry(snod, &sleb->nodes, list) { + struct ubifs_idx_node *idx; + int in_use, level; + + ubifs_assert(c, snod->type == UBIFS_IDX_NODE); + idx = snod->node; + key_read(c, ubifs_idx_key(c, idx), &snod->key); + level = le16_to_cpu(idx->level); + /* Determine if the index node is in use (not obsolete) */ + in_use = is_idx_node_in_use(c, &snod->key, level, lnum, + snod->offs); + if (in_use < 0) { + ubifs_scan_destroy(sleb); + return in_use; /* Error code */ + } + if (in_use) { + if (in_use == 1) + dirt += ALIGN(snod->len, 8); + /* + * The obsolete index nodes form gaps that can be + * overwritten. This gap has ended because we have + * found an index node that is still in use + * i.e. not obsolete + */ + gap_end = snod->offs; + /* Try to fill gap */ + written = fill_gap(c, lnum, gap_start, gap_end, &dirt); + if (written < 0) { + ubifs_scan_destroy(sleb); + return written; /* Error code */ + } + tot_written += written; + gap_start = ALIGN(snod->offs + snod->len, 8); + } + } + ubifs_scan_destroy(sleb); + c->ileb_len = c->leb_size; + gap_end = c->leb_size; + /* Try to fill gap */ + written = fill_gap(c, lnum, gap_start, gap_end, &dirt); + if (written < 0) + return written; /* Error code */ + tot_written += written; + if (tot_written == 0) { + struct ubifs_lprops lp; + + dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written); + err = ubifs_read_one_lp(c, lnum, &lp); + if (err) + return err; + if (lp.free == c->leb_size) { + /* + * We must have snatched this LEB from the idx_gc list + * so we need to correct the free and dirty space. + */ + err = ubifs_change_one_lp(c, lnum, + c->leb_size - c->ileb_len, + dirt, 0, 0, 0); + if (err) + return err; + } + return 0; + } + err = ubifs_change_one_lp(c, lnum, c->leb_size - c->ileb_len, dirt, + 0, 0, 0); + if (err) + return err; + err = ubifs_leb_change(c, lnum, c->ileb_buf, c->ileb_len); + if (err) + return err; + dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written); + return tot_written; +} + +/** + * get_leb_cnt - calculate the number of empty LEBs needed to commit. + * @c: UBIFS file-system description object + * @cnt: number of znodes to commit + * + * This function returns the number of empty LEBs needed to commit @cnt znodes + * to the current index head. The number is not exact and may be more than + * needed. + */ +static int get_leb_cnt(struct ubifs_info *c, int cnt) +{ + int d; + + /* Assume maximum index node size (i.e. overestimate space needed) */ + cnt -= (c->leb_size - c->ihead_offs) / c->max_idx_node_sz; + if (cnt < 0) + cnt = 0; + d = c->leb_size / c->max_idx_node_sz; + return DIV_ROUND_UP(cnt, d); +} + +/** + * layout_in_gaps - in-the-gaps method of committing TNC. + * @c: UBIFS file-system description object + * @cnt: number of dirty znodes to commit. + * + * This function lays out new index nodes for dirty znodes using in-the-gaps + * method of TNC commit. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int layout_in_gaps(struct ubifs_info *c, int cnt) +{ + int err, leb_needed_cnt, written, p = 0, old_idx_lebs, *gap_lebs; + + dbg_gc("%d znodes to write", cnt); + + c->gap_lebs = kmalloc_array(c->lst.idx_lebs + 1, sizeof(int), + GFP_NOFS); + if (!c->gap_lebs) + return -ENOMEM; + + old_idx_lebs = c->lst.idx_lebs; + do { + ubifs_assert(c, p < c->lst.idx_lebs); + written = layout_leb_in_gaps(c, p); + if (written < 0) { + err = written; + if (err != -ENOSPC) { + kfree(c->gap_lebs); + c->gap_lebs = NULL; + return err; + } + if (!dbg_is_chk_index(c)) { + /* + * Do not print scary warnings if the debugging + * option which forces in-the-gaps is enabled. + */ + ubifs_warn(c, "out of space"); + ubifs_dump_budg(c, &c->bi); + ubifs_dump_lprops(c); + } + /* Try to commit anyway */ + break; + } + p++; + cnt -= written; + leb_needed_cnt = get_leb_cnt(c, cnt); + dbg_gc("%d znodes remaining, need %d LEBs, have %d", cnt, + leb_needed_cnt, c->ileb_cnt); + /* + * Dynamically change the size of @c->gap_lebs to prevent + * oob, because @c->lst.idx_lebs could be increased by + * function @get_idx_gc_leb (called by layout_leb_in_gaps-> + * ubifs_find_dirty_idx_leb) during loop. Only enlarge + * @c->gap_lebs when needed. + * + */ + if (leb_needed_cnt > c->ileb_cnt && p >= old_idx_lebs && + old_idx_lebs < c->lst.idx_lebs) { + old_idx_lebs = c->lst.idx_lebs; + gap_lebs = krealloc(c->gap_lebs, sizeof(int) * + (old_idx_lebs + 1), GFP_NOFS); + if (!gap_lebs) { + kfree(c->gap_lebs); + c->gap_lebs = NULL; + return -ENOMEM; + } + c->gap_lebs = gap_lebs; + } + } while (leb_needed_cnt > c->ileb_cnt); + + c->gap_lebs[p] = -1; + return 0; +} + +/** + * layout_in_empty_space - layout index nodes in empty space. + * @c: UBIFS file-system description object + * + * This function lays out new index nodes for dirty znodes using empty LEBs. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int layout_in_empty_space(struct ubifs_info *c) +{ + struct ubifs_znode *znode, *cnext, *zp; + int lnum, offs, len, next_len, buf_len, buf_offs, used, avail; + int wlen, blen, err; + + cnext = c->enext; + if (!cnext) + return 0; + + lnum = c->ihead_lnum; + buf_offs = c->ihead_offs; + + buf_len = ubifs_idx_node_sz(c, c->fanout); + buf_len = ALIGN(buf_len, c->min_io_size); + used = 0; + avail = buf_len; + + /* Ensure there is enough room for first write */ + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + if (buf_offs + next_len > c->leb_size) + lnum = -1; + + while (1) { + znode = cnext; + + len = ubifs_idx_node_sz(c, znode->child_cnt); + + /* Determine the index node position */ + if (lnum == -1) { + if (c->ileb_nxt >= c->ileb_cnt) { + ubifs_err(c, "out of space"); + return -ENOSPC; + } + lnum = c->ilebs[c->ileb_nxt++]; + buf_offs = 0; + used = 0; + avail = buf_len; + } + + offs = buf_offs + used; + + znode->lnum = lnum; + znode->offs = offs; + znode->len = len; + + /* Update the parent */ + zp = znode->parent; + if (zp) { + struct ubifs_zbranch *zbr; + int i; + + i = znode->iip; + zbr = &zp->zbranch[i]; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + } else { + c->zroot.lnum = lnum; + c->zroot.offs = offs; + c->zroot.len = len; + } + c->calc_idx_sz += ALIGN(len, 8); + + /* + * Once lprops is updated, we can decrease the dirty znode count + * but it is easier to just do it here. + */ + atomic_long_dec(&c->dirty_zn_cnt); + + /* + * Calculate the next index node length to see if there is + * enough room for it + */ + cnext = znode->cnext; + if (cnext == c->cnext) + next_len = 0; + else + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + + /* Update buffer positions */ + wlen = used + len; + used += ALIGN(len, 8); + avail -= ALIGN(len, 8); + + if (next_len != 0 && + buf_offs + used + next_len <= c->leb_size && + avail > 0) + continue; + + if (avail <= 0 && next_len && + buf_offs + used + next_len <= c->leb_size) + blen = buf_len; + else + blen = ALIGN(wlen, c->min_io_size); + + /* The buffer is full or there are no more znodes to do */ + buf_offs += blen; + if (next_len) { + if (buf_offs + next_len > c->leb_size) { + err = ubifs_update_one_lp(c, lnum, + c->leb_size - buf_offs, blen - used, + 0, 0); + if (err) + return err; + lnum = -1; + } + used -= blen; + if (used < 0) + used = 0; + avail = buf_len - used; + continue; + } + err = ubifs_update_one_lp(c, lnum, c->leb_size - buf_offs, + blen - used, 0, 0); + if (err) + return err; + break; + } + + c->new_ihead_lnum = lnum; + c->new_ihead_offs = buf_offs; + + return 0; +} + +/** + * layout_commit - determine positions of index nodes to commit. + * @c: UBIFS file-system description object + * @no_space: indicates that insufficient empty LEBs were allocated + * @cnt: number of znodes to commit + * + * Calculate and update the positions of index nodes to commit. If there were + * an insufficient number of empty LEBs allocated, then index nodes are placed + * into the gaps created by obsolete index nodes in non-empty index LEBs. For + * this purpose, an obsolete index node is one that was not in the index as at + * the end of the last commit. To write "in-the-gaps" requires that those index + * LEBs are updated atomically in-place. + */ +static int layout_commit(struct ubifs_info *c, int no_space, int cnt) +{ + int err; + + if (no_space) { + err = layout_in_gaps(c, cnt); + if (err) + return err; + } + err = layout_in_empty_space(c); + return err; +} + +/** + * find_first_dirty - find first dirty znode. + * @znode: znode to begin searching from + */ +static struct ubifs_znode *find_first_dirty(struct ubifs_znode *znode) +{ + int i, cont; + + if (!znode) + return NULL; + + while (1) { + if (znode->level == 0) { + if (ubifs_zn_dirty(znode)) + return znode; + return NULL; + } + cont = 0; + for (i = 0; i < znode->child_cnt; i++) { + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + if (zbr->znode && ubifs_zn_dirty(zbr->znode)) { + znode = zbr->znode; + cont = 1; + break; + } + } + if (!cont) { + if (ubifs_zn_dirty(znode)) + return znode; + return NULL; + } + } +} + +/** + * find_next_dirty - find next dirty znode. + * @znode: znode to begin searching from + */ +static struct ubifs_znode *find_next_dirty(struct ubifs_znode *znode) +{ + int n = znode->iip + 1; + + znode = znode->parent; + if (!znode) + return NULL; + for (; n < znode->child_cnt; n++) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + if (zbr->znode && ubifs_zn_dirty(zbr->znode)) + return find_first_dirty(zbr->znode); + } + return znode; +} + +/** + * get_znodes_to_commit - create list of dirty znodes to commit. + * @c: UBIFS file-system description object + * + * This function returns the number of znodes to commit. + */ +static int get_znodes_to_commit(struct ubifs_info *c) +{ + struct ubifs_znode *znode, *cnext; + int cnt = 0; + + c->cnext = find_first_dirty(c->zroot.znode); + znode = c->enext = c->cnext; + if (!znode) { + dbg_cmt("no znodes to commit"); + return 0; + } + cnt += 1; + while (1) { + ubifs_assert(c, !ubifs_zn_cow(znode)); + __set_bit(COW_ZNODE, &znode->flags); + znode->alt = 0; + cnext = find_next_dirty(znode); + if (!cnext) { + ubifs_assert(c, !znode->parent); + znode->cparent = NULL; + znode->cnext = c->cnext; + break; + } + znode->cparent = znode->parent; + znode->ciip = znode->iip; + znode->cnext = cnext; + znode = cnext; + cnt += 1; + } + dbg_cmt("committing %d znodes", cnt); + ubifs_assert(c, cnt == atomic_long_read(&c->dirty_zn_cnt)); + return cnt; +} + +/** + * alloc_idx_lebs - allocate empty LEBs to be used to commit. + * @c: UBIFS file-system description object + * @cnt: number of znodes to commit + * + * This function returns %-ENOSPC if it cannot allocate a sufficient number of + * empty LEBs. %0 is returned on success, otherwise a negative error code + * is returned. + */ +static int alloc_idx_lebs(struct ubifs_info *c, int cnt) +{ + int i, leb_cnt, lnum; + + c->ileb_cnt = 0; + c->ileb_nxt = 0; + leb_cnt = get_leb_cnt(c, cnt); + dbg_cmt("need about %d empty LEBS for TNC commit", leb_cnt); + if (!leb_cnt) + return 0; + c->ilebs = kmalloc_array(leb_cnt, sizeof(int), GFP_NOFS); + if (!c->ilebs) + return -ENOMEM; + for (i = 0; i < leb_cnt; i++) { + lnum = ubifs_find_free_leb_for_idx(c); + if (lnum < 0) + return lnum; + c->ilebs[c->ileb_cnt++] = lnum; + dbg_cmt("LEB %d", lnum); + } + if (dbg_is_chk_index(c)) + return -ENOSPC; + return 0; +} + +/** + * free_unused_idx_lebs - free unused LEBs that were allocated for the commit. + * @c: UBIFS file-system description object + * + * It is possible that we allocate more empty LEBs for the commit than we need. + * This functions frees the surplus. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int free_unused_idx_lebs(struct ubifs_info *c) +{ + int i, err = 0, lnum, er; + + for (i = c->ileb_nxt; i < c->ileb_cnt; i++) { + lnum = c->ilebs[i]; + dbg_cmt("LEB %d", lnum); + er = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0, + LPROPS_INDEX | LPROPS_TAKEN, 0); + if (!err) + err = er; + } + return err; +} + +/** + * free_idx_lebs - free unused LEBs after commit end. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int free_idx_lebs(struct ubifs_info *c) +{ + int err; + + err = free_unused_idx_lebs(c); + kfree(c->ilebs); + c->ilebs = NULL; + return err; +} + +/** + * ubifs_tnc_start_commit - start TNC commit. + * @c: UBIFS file-system description object + * @zroot: new index root position is returned here + * + * This function prepares the list of indexing nodes to commit and lays out + * their positions on flash. If there is not enough free space it uses the + * in-gap commit method. Returns zero in case of success and a negative error + * code in case of failure. + */ +int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot) +{ + int err = 0, cnt; + + mutex_lock(&c->tnc_mutex); + err = dbg_check_tnc(c, 1); + if (err) + goto out; + cnt = get_znodes_to_commit(c); + if (cnt != 0) { + int no_space = 0; + + err = alloc_idx_lebs(c, cnt); + if (err == -ENOSPC) + no_space = 1; + else if (err) + goto out_free; + err = layout_commit(c, no_space, cnt); + if (err) + goto out_free; + ubifs_assert(c, atomic_long_read(&c->dirty_zn_cnt) == 0); + err = free_unused_idx_lebs(c); + if (err) + goto out; + } + destroy_old_idx(c); + memcpy(zroot, &c->zroot, sizeof(struct ubifs_zbranch)); + + err = ubifs_save_dirty_idx_lnums(c); + if (err) + goto out; + + spin_lock(&c->space_lock); + /* + * Although we have not finished committing yet, update size of the + * committed index ('c->bi.old_idx_sz') and zero out the index growth + * budget. It is OK to do this now, because we've reserved all the + * space which is needed to commit the index, and it is save for the + * budgeting subsystem to assume the index is already committed, + * even though it is not. + */ + ubifs_assert(c, c->bi.min_idx_lebs == ubifs_calc_min_idx_lebs(c)); + c->bi.old_idx_sz = c->calc_idx_sz; + c->bi.uncommitted_idx = 0; + c->bi.min_idx_lebs = ubifs_calc_min_idx_lebs(c); + spin_unlock(&c->space_lock); + mutex_unlock(&c->tnc_mutex); + + dbg_cmt("number of index LEBs %d", c->lst.idx_lebs); + dbg_cmt("size of index %llu", c->calc_idx_sz); + return err; + +out_free: + free_idx_lebs(c); +out: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * write_index - write index nodes. + * @c: UBIFS file-system description object + * + * This function writes the index nodes whose positions were laid out in the + * layout_in_empty_space function. + */ +static int write_index(struct ubifs_info *c) +{ + struct ubifs_idx_node *idx; + struct ubifs_znode *znode, *cnext; + int i, lnum, offs, len, next_len, buf_len, buf_offs, used; + int avail, wlen, err, lnum_pos = 0, blen, nxt_offs; + + cnext = c->enext; + if (!cnext) + return 0; + + /* + * Always write index nodes to the index head so that index nodes and + * other types of nodes are never mixed in the same erase block. + */ + lnum = c->ihead_lnum; + buf_offs = c->ihead_offs; + + /* Allocate commit buffer */ + buf_len = ALIGN(c->max_idx_node_sz, c->min_io_size); + used = 0; + avail = buf_len; + + /* Ensure there is enough room for first write */ + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + if (buf_offs + next_len > c->leb_size) { + err = ubifs_update_one_lp(c, lnum, LPROPS_NC, 0, 0, + LPROPS_TAKEN); + if (err) + return err; + lnum = -1; + } + + while (1) { + u8 hash[UBIFS_HASH_ARR_SZ]; + + cond_resched(); + + znode = cnext; + idx = c->cbuf + used; + + /* Make index node */ + idx->ch.node_type = UBIFS_IDX_NODE; + idx->child_cnt = cpu_to_le16(znode->child_cnt); + idx->level = cpu_to_le16(znode->level); + for (i = 0; i < znode->child_cnt; i++) { + struct ubifs_branch *br = ubifs_idx_branch(c, idx, i); + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + key_write_idx(c, &zbr->key, &br->key); + br->lnum = cpu_to_le32(zbr->lnum); + br->offs = cpu_to_le32(zbr->offs); + br->len = cpu_to_le32(zbr->len); + ubifs_copy_hash(c, zbr->hash, ubifs_branch_hash(c, br)); + if (!zbr->lnum || !zbr->len) { + ubifs_err(c, "bad ref in znode"); + ubifs_dump_znode(c, znode); + if (zbr->znode) + ubifs_dump_znode(c, zbr->znode); + + return -EINVAL; + } + } + len = ubifs_idx_node_sz(c, znode->child_cnt); + ubifs_prepare_node(c, idx, len, 0); + ubifs_node_calc_hash(c, idx, hash); + + mutex_lock(&c->tnc_mutex); + + if (znode->cparent) + ubifs_copy_hash(c, hash, + znode->cparent->zbranch[znode->ciip].hash); + + if (znode->parent) { + if (!ubifs_zn_obsolete(znode)) + ubifs_copy_hash(c, hash, + znode->parent->zbranch[znode->iip].hash); + } else { + ubifs_copy_hash(c, hash, c->zroot.hash); + } + + mutex_unlock(&c->tnc_mutex); + + /* Determine the index node position */ + if (lnum == -1) { + lnum = c->ilebs[lnum_pos++]; + buf_offs = 0; + used = 0; + avail = buf_len; + } + offs = buf_offs + used; + + if (lnum != znode->lnum || offs != znode->offs || + len != znode->len) { + ubifs_err(c, "inconsistent znode posn"); + return -EINVAL; + } + + /* Grab some stuff from znode while we still can */ + cnext = znode->cnext; + + ubifs_assert(c, ubifs_zn_dirty(znode)); + ubifs_assert(c, ubifs_zn_cow(znode)); + + /* + * It is important that other threads should see %DIRTY_ZNODE + * flag cleared before %COW_ZNODE. Specifically, it matters in + * the 'dirty_cow_znode()' function. This is the reason for the + * first barrier. Also, we want the bit changes to be seen to + * other threads ASAP, to avoid unnecessary copying, which is + * the reason for the second barrier. + */ + clear_bit(DIRTY_ZNODE, &znode->flags); + smp_mb__before_atomic(); + clear_bit(COW_ZNODE, &znode->flags); + smp_mb__after_atomic(); + + /* + * We have marked the znode as clean but have not updated the + * @c->clean_zn_cnt counter. If this znode becomes dirty again + * before 'free_obsolete_znodes()' is called, then + * @c->clean_zn_cnt will be decremented before it gets + * incremented (resulting in 2 decrements for the same znode). + * This means that @c->clean_zn_cnt may become negative for a + * while. + * + * Q: why we cannot increment @c->clean_zn_cnt? + * A: because we do not have the @c->tnc_mutex locked, and the + * following code would be racy and buggy: + * + * if (!ubifs_zn_obsolete(znode)) { + * atomic_long_inc(&c->clean_zn_cnt); + * atomic_long_inc(&ubifs_clean_zn_cnt); + * } + * + * Thus, we just delay the @c->clean_zn_cnt update until we + * have the mutex locked. + */ + + /* Do not access znode from this point on */ + + /* Update buffer positions */ + wlen = used + len; + used += ALIGN(len, 8); + avail -= ALIGN(len, 8); + + /* + * Calculate the next index node length to see if there is + * enough room for it + */ + if (cnext == c->cnext) + next_len = 0; + else + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + + nxt_offs = buf_offs + used + next_len; + if (next_len && nxt_offs <= c->leb_size) { + if (avail > 0) + continue; + else + blen = buf_len; + } else { + wlen = ALIGN(wlen, 8); + blen = ALIGN(wlen, c->min_io_size); + ubifs_pad(c, c->cbuf + wlen, blen - wlen); + } + + /* The buffer is full or there are no more znodes to do */ + err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs, blen); + if (err) + return err; + buf_offs += blen; + if (next_len) { + if (nxt_offs > c->leb_size) { + err = ubifs_update_one_lp(c, lnum, LPROPS_NC, 0, + 0, LPROPS_TAKEN); + if (err) + return err; + lnum = -1; + } + used -= blen; + if (used < 0) + used = 0; + avail = buf_len - used; + memmove(c->cbuf, c->cbuf + blen, used); + continue; + } + break; + } + + if (lnum != c->new_ihead_lnum || + buf_offs != c->new_ihead_offs) { + ubifs_err(c, "inconsistent ihead"); + return -EINVAL; + } + + c->ihead_lnum = lnum; + c->ihead_offs = buf_offs; + + return 0; +} + +/** + * free_obsolete_znodes - free obsolete znodes. + * @c: UBIFS file-system description object + * + * At the end of commit end, obsolete znodes are freed. + */ +static void free_obsolete_znodes(struct ubifs_info *c) +{ + struct ubifs_znode *znode, *cnext; + + cnext = c->cnext; + do { + znode = cnext; + cnext = znode->cnext; + if (ubifs_zn_obsolete(znode)) + kfree(znode); + else { + znode->cnext = NULL; + atomic_long_inc(&c->clean_zn_cnt); + atomic_long_inc(&ubifs_clean_zn_cnt); + } + } while (cnext != c->cnext); +} + +/** + * return_gap_lebs - return LEBs used by the in-gap commit method. + * @c: UBIFS file-system description object + * + * This function clears the "taken" flag for the LEBs which were used by the + * "commit in-the-gaps" method. + */ +static int return_gap_lebs(struct ubifs_info *c) +{ + int *p, err; + + if (!c->gap_lebs) + return 0; + + dbg_cmt(""); + for (p = c->gap_lebs; *p != -1; p++) { + err = ubifs_change_one_lp(c, *p, LPROPS_NC, LPROPS_NC, 0, + LPROPS_TAKEN, 0); + if (err) + return err; + } + + kfree(c->gap_lebs); + c->gap_lebs = NULL; + return 0; +} + +/** + * ubifs_tnc_end_commit - update the TNC for commit end. + * @c: UBIFS file-system description object + * + * Write the dirty znodes. + */ +int ubifs_tnc_end_commit(struct ubifs_info *c) +{ + int err; + + if (!c->cnext) + return 0; + + err = return_gap_lebs(c); + if (err) + return err; + + err = write_index(c); + if (err) + return err; + + mutex_lock(&c->tnc_mutex); + + dbg_cmt("TNC height is %d", c->zroot.znode->level + 1); + + free_obsolete_znodes(c); + + c->cnext = NULL; + kfree(c->ilebs); + c->ilebs = NULL; + + mutex_unlock(&c->tnc_mutex); + + return 0; +} diff --git a/ubifs-utils/libubifs/tnc_misc.c b/ubifs-utils/libubifs/tnc_misc.c new file mode 100644 index 0000000..0ffb434 --- /dev/null +++ b/ubifs-utils/libubifs/tnc_misc.c @@ -0,0 +1,452 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file contains miscelanious TNC-related functions shared betweend + * different files. This file does not form any logically separate TNC + * sub-system. The file was created because there is a lot of TNC code and + * putting it all in one file would make that file too big and unreadable. + */ + +#include "linux_err.h" +#include "bitops.h" +#include "kmem.h" +#include "ubifs.h" +#include "defs.h" +#include "debug.h" +#include "key.h" +#include "misc.h" + +/** + * ubifs_search_zbranch - search znode branch. + * @c: UBIFS file-system description object + * @znode: znode to search in + * @key: key to search for + * @n: znode branch slot number is returned here + * + * This is a helper function which search branch with key @key in @znode using + * binary search. The result of the search may be: + * o exact match, then %1 is returned, and the slot number of the branch is + * stored in @n; + * o no exact match, then %0 is returned and the slot number of the left + * closest branch is returned in @n; the slot if all keys in this znode are + * greater than @key, then %-1 is returned in @n. + */ +int ubifs_search_zbranch(const struct ubifs_info *c, + const struct ubifs_znode *znode, + const union ubifs_key *key, int *n) +{ + int beg = 0, end = znode->child_cnt, mid; + int cmp; + const struct ubifs_zbranch *zbr = &znode->zbranch[0]; + + if (!end) { + /* Different with linux kernel, TNC could become empty. */ + *n = -1; + return 0; + } + + ubifs_assert(c, end > beg); + + while (end > beg) { + mid = (beg + end) >> 1; + cmp = keys_cmp(c, key, &zbr[mid].key); + if (cmp > 0) + beg = mid + 1; + else if (cmp < 0) + end = mid; + else { + *n = mid; + return 1; + } + } + + *n = end - 1; + + /* The insert point is after *n */ + ubifs_assert(c, *n >= -1 && *n < znode->child_cnt); + if (*n == -1) + ubifs_assert(c, keys_cmp(c, key, &zbr[0].key) < 0); + else + ubifs_assert(c, keys_cmp(c, key, &zbr[*n].key) > 0); + if (*n + 1 < znode->child_cnt) + ubifs_assert(c, keys_cmp(c, key, &zbr[*n + 1].key) < 0); + + return 0; +} + +/** + * ubifs_tnc_postorder_first - find first znode to do postorder tree traversal. + * @znode: znode to start at (root of the sub-tree to traverse) + * + * Find the lowest leftmost znode in a subtree of the TNC tree. The LNC is + * ignored. + */ +struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode) +{ + if (unlikely(!znode)) + return NULL; + + while (znode->level > 0) { + struct ubifs_znode *child; + + child = ubifs_tnc_find_child(znode, 0); + if (!child) + return znode; + znode = child; + } + + return znode; +} + +/** + * ubifs_tnc_postorder_next - next TNC tree element in postorder traversal. + * @c: UBIFS file-system description object + * @znode: previous znode + * + * This function implements postorder TNC traversal. The LNC is ignored. + * Returns the next element or %NULL if @znode is already the last one. + */ +struct ubifs_znode *ubifs_tnc_postorder_next(const struct ubifs_info *c, + struct ubifs_znode *znode) +{ + struct ubifs_znode *zn; + + ubifs_assert(c, znode); + if (unlikely(!znode->parent)) + return NULL; + + /* Switch to the next index in the parent */ + zn = ubifs_tnc_find_child(znode->parent, znode->iip + 1); + if (!zn) + /* This is in fact the last child, return parent */ + return znode->parent; + + /* Go to the first znode in this new subtree */ + return ubifs_tnc_postorder_first(zn); +} + +/** + * ubifs_destroy_tnc_subtree - destroy all znodes connected to a subtree. + * @c: UBIFS file-system description object + * @znode: znode defining subtree to destroy + * + * This function destroys subtree of the TNC tree. Returns number of clean + * znodes in the subtree. + */ +long ubifs_destroy_tnc_subtree(const struct ubifs_info *c, + struct ubifs_znode *znode) +{ + struct ubifs_znode *zn = ubifs_tnc_postorder_first(znode); + long clean_freed = 0; + int n; + + ubifs_assert(c, zn); + while (1) { + for (n = 0; n < zn->child_cnt; n++) { + if (!zn->zbranch[n].znode) + continue; + + if (zn->level > 0 && + !ubifs_zn_dirty(zn->zbranch[n].znode)) + clean_freed += 1; + + cond_resched(); + kfree(zn->zbranch[n].znode); + } + + if (zn == znode) { + if (!ubifs_zn_dirty(zn)) + clean_freed += 1; + kfree(zn); + return clean_freed; + } + + zn = ubifs_tnc_postorder_next(c, zn); + } +} + +/** + * ubifs_destroy_tnc_tree - destroy all znodes connected to the TNC tree. + * @c: UBIFS file-system description object + * + * This function destroys the whole TNC tree and updates clean global znode + * count. + */ +void ubifs_destroy_tnc_tree(struct ubifs_info *c) +{ + long n, freed; + + if (!c->zroot.znode) + return; + + n = atomic_long_read(&c->clean_zn_cnt); + freed = ubifs_destroy_tnc_subtree(c, c->zroot.znode); + ubifs_assert(c, freed == n); + atomic_long_sub(n, &ubifs_clean_zn_cnt); + + c->zroot.znode = NULL; +} + +/** + * read_znode - read an indexing node from flash and fill znode. + * @c: UBIFS file-system description object + * @zzbr: the zbranch describing the node to read + * @znode: znode to read to + * + * This function reads an indexing node from the flash media and fills znode + * with the read data. Returns zero in case of success and a negative error + * code in case of failure. The read indexing node is validated and if anything + * is wrong with it, this function prints complaint messages and returns + * %-EINVAL. + */ +static int read_znode(struct ubifs_info *c, struct ubifs_zbranch *zzbr, + struct ubifs_znode *znode) +{ + int lnum = zzbr->lnum; + int offs = zzbr->offs; + int len = zzbr->len; + int i, err, type, cmp; + struct ubifs_idx_node *idx; + + idx = kmalloc(c->max_idx_node_sz, GFP_NOFS); + if (!idx) + return -ENOMEM; + + err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs); + if (err < 0) { + if (test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED)) + set_failure_reason_callback(c, FR_TNC_CORRUPTED); + kfree(idx); + return err; + } + + err = ubifs_node_check_hash(c, idx, zzbr->hash); + if (err) { + ubifs_bad_hash(c, idx, zzbr->hash, lnum, offs); + kfree(idx); + return err; + } + + znode->child_cnt = le16_to_cpu(idx->child_cnt); + znode->level = le16_to_cpu(idx->level); + + dbg_tnc("LEB %d:%d, level %d, %d branch", + lnum, offs, znode->level, znode->child_cnt); + + if (znode->child_cnt > c->fanout || znode->level > UBIFS_MAX_LEVELS) { + ubifs_err(c, "current fanout %d, branch count %d", + c->fanout, znode->child_cnt); + ubifs_err(c, "max levels %d, znode level %d", + UBIFS_MAX_LEVELS, znode->level); + err = 1; + goto out_dump; + } + + for (i = 0; i < znode->child_cnt; i++) { + struct ubifs_branch *br = ubifs_idx_branch(c, idx, i); + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + key_read(c, &br->key, &zbr->key); + zbr->lnum = le32_to_cpu(br->lnum); + zbr->offs = le32_to_cpu(br->offs); + zbr->len = le32_to_cpu(br->len); + ubifs_copy_hash(c, ubifs_branch_hash(c, br), zbr->hash); + zbr->znode = NULL; + + /* Validate branch */ + + if (zbr->lnum < c->main_first || + zbr->lnum >= c->leb_cnt || zbr->offs < 0 || + zbr->offs + zbr->len > c->leb_size || zbr->offs & 7) { + ubifs_err(c, "bad branch %d", i); + err = 2; + goto out_dump; + } + + switch (key_type(c, &zbr->key)) { + case UBIFS_INO_KEY: + case UBIFS_DATA_KEY: + case UBIFS_DENT_KEY: + case UBIFS_XENT_KEY: + break; + default: + ubifs_err(c, "bad key type at slot %d: %d", + i, key_type(c, &zbr->key)); + err = 3; + goto out_dump; + } + + if (znode->level) + type = UBIFS_IDX_NODE; + else + type = key_type(c, &zbr->key); + + if (c->ranges[type].max_len == 0) { + if (zbr->len != c->ranges[type].len) { + ubifs_err(c, "bad target node (type %d) length (%d)", + type, zbr->len); + ubifs_err(c, "have to be %d", c->ranges[type].len); + err = 4; + goto out_dump; + } + } else if (zbr->len < c->ranges[type].min_len || + zbr->len > c->ranges[type].max_len) { + ubifs_err(c, "bad target node (type %d) length (%d)", + type, zbr->len); + ubifs_err(c, "have to be in range of %d-%d", + c->ranges[type].min_len, + c->ranges[type].max_len); + err = 5; + goto out_dump; + } + } + + /* + * Ensure that the next key is greater or equivalent to the + * previous one. + */ + for (i = 0; i < znode->child_cnt - 1; i++) { + const union ubifs_key *key1, *key2; + + key1 = &znode->zbranch[i].key; + key2 = &znode->zbranch[i + 1].key; + + cmp = keys_cmp(c, key1, key2); + if (cmp > 0) { + ubifs_err(c, "bad key order (keys %d and %d)", i, i + 1); + err = 6; + goto out_dump; + } else if (cmp == 0 && !is_hash_key(c, key1)) { + /* These can only be keys with colliding hash */ + ubifs_err(c, "keys %d and %d are not hashed but equivalent", + i, i + 1); + err = 7; + goto out_dump; + } + } + + kfree(idx); + return 0; + +out_dump: + set_failure_reason_callback(c, FR_TNC_CORRUPTED); + ubifs_err(c, "bad indexing node at LEB %d:%d, error %d", lnum, offs, err); + ubifs_dump_node(c, idx, c->max_idx_node_sz); + kfree(idx); + return -EINVAL; +} + +/** + * ubifs_load_znode - load znode to TNC cache. + * @c: UBIFS file-system description object + * @zbr: znode branch + * @parent: znode's parent + * @iip: index in parent + * + * This function loads znode pointed to by @zbr into the TNC cache and + * returns pointer to it in case of success and a negative error code in case + * of failure. + */ +struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c, + struct ubifs_zbranch *zbr, + struct ubifs_znode *parent, int iip) +{ + int err; + struct ubifs_znode *znode; + + ubifs_assert(c, !zbr->znode); + /* + * A slab cache is not presently used for znodes because the znode size + * depends on the fanout which is stored in the superblock. + */ + znode = kzalloc(c->max_znode_sz, GFP_NOFS); + if (!znode) + return ERR_PTR(-ENOMEM); + + err = read_znode(c, zbr, znode); + if (err) + goto out; + + atomic_long_inc(&c->clean_zn_cnt); + + /* + * Increment the global clean znode counter as well. It is OK that + * global and per-FS clean znode counters may be inconsistent for some + * short time (because we might be preempted at this point), the global + * one is only used in shrinker. + */ + atomic_long_inc(&ubifs_clean_zn_cnt); + + zbr->znode = znode; + znode->parent = parent; + znode->time = ktime_get_seconds(); + znode->iip = iip; + + return znode; + +out: + kfree(znode); + return ERR_PTR(err); +} + +/** + * ubifs_tnc_read_node - read a leaf node from the flash media. + * @c: UBIFS file-system description object + * @zbr: key and position of the node + * @node: node is returned here + * + * This function reads a node defined by @zbr from the flash media. Returns + * zero in case of success or a negative error code in case of failure. + */ +int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node) +{ + union ubifs_key key1, *key = &zbr->key; + int err, type = key_type(c, key); + struct ubifs_wbuf *wbuf; + + /* + * 'zbr' has to point to on-flash node. The node may sit in a bud and + * may even be in a write buffer, so we have to take care about this. + */ + wbuf = ubifs_get_wbuf(c, zbr->lnum); + if (wbuf) + err = ubifs_read_node_wbuf(wbuf, node, type, zbr->len, + zbr->lnum, zbr->offs); + else + err = ubifs_read_node(c, node, type, zbr->len, zbr->lnum, + zbr->offs); + + if (err) { + dbg_tnck(key, "key "); + return err; + } + + /* Make sure the key of the read node is correct */ + key_read(c, node + UBIFS_KEY_OFFSET, &key1); + if (!keys_eq(c, key, &key1)) { + set_failure_reason_callback(c, FR_DATA_CORRUPTED); + ubifs_err(c, "bad key in node at LEB %d:%d", + zbr->lnum, zbr->offs); + dbg_tnck(key, "looked for key "); + dbg_tnck(&key1, "but found node's key "); + ubifs_dump_node(c, node, zbr->len); + return -EINVAL; + } + + err = ubifs_node_check_hash(c, node, zbr->hash); + if (err) { + ubifs_bad_hash(c, node, zbr->hash, zbr->lnum, zbr->offs); + return err; + } + + return 0; +} diff --git a/ubifs-utils/libubifs/ubifs-media.h b/ubifs-utils/libubifs/ubifs-media.h new file mode 100644 index 0000000..f1e3a14 --- /dev/null +++ b/ubifs-utils/libubifs/ubifs-media.h @@ -0,0 +1,869 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file describes UBIFS on-flash format and contains definitions of all the + * relevant data structures and constants. + * + * All UBIFS on-flash objects are stored in the form of nodes. All nodes start + * with the UBIFS node magic number and have the same common header. Nodes + * always sit at 8-byte aligned positions on the media and node header sizes are + * also 8-byte aligned (except for the indexing node and the padding node). + */ + +#ifndef __UBIFS_MEDIA_H__ +#define __UBIFS_MEDIA_H__ + +#include <asm/byteorder.h> + +/* UBIFS node magic number (must not have the padding byte first or last) */ +#define UBIFS_NODE_MAGIC 0x06101831 + +/* + * UBIFS on-flash format version. This version is increased when the on-flash + * format is changing. If this happens, UBIFS is will support older versions as + * well. But older UBIFS code will not support newer formats. Format changes + * will be rare and only when absolutely necessary, e.g. to fix a bug or to add + * a new feature. + * + * UBIFS went into mainline kernel with format version 4. The older formats + * were development formats. + */ +#define UBIFS_FORMAT_VERSION 5 + +/* + * Read-only compatibility version. If the UBIFS format is changed, older UBIFS + * implementations will not be able to mount newer formats in read-write mode. + * However, depending on the change, it may be possible to mount newer formats + * in R/O mode. This is indicated by the R/O compatibility version which is + * stored in the super-block. + * + * This is needed to support boot-loaders which only need R/O mounting. With + * this flag it is possible to do UBIFS format changes without a need to update + * boot-loaders. + */ +#define UBIFS_RO_COMPAT_VERSION 0 + +/* Minimum logical eraseblock size in bytes */ +#define UBIFS_MIN_LEB_SZ (15*1024) + +/* Initial CRC32 value used when calculating CRC checksums */ +#define UBIFS_CRC32_INIT 0xFFFFFFFFU + +/* + * UBIFS does not try to compress data if its length is less than the below + * constant. + */ +#define UBIFS_MIN_COMPR_LEN 128 + +/* + * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes + * shorter than uncompressed data length, UBIFS prefers to leave this data + * node uncompress, because it'll be read faster. + */ +#define UBIFS_MIN_COMPRESS_DIFF 64 + +/* Root inode number */ +#define UBIFS_ROOT_INO 1 + +/* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */ +#define UBIFS_FIRST_INO 64 + +/* + * Maximum file name and extended attribute length (must be a multiple of 8, + * minus 1). + */ +#define UBIFS_MAX_NLEN 255 + +/* Maximum number of data journal heads */ +#define UBIFS_MAX_JHEADS 1 + +/* + * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system, + * which means that it does not treat the underlying media as consisting of + * blocks like in case of hard drives. Do not be confused. UBIFS block is just + * the maximum amount of data which one data node can have or which can be + * attached to an inode node. + */ +#define UBIFS_BLOCK_SIZE 4096 +#define UBIFS_BLOCK_SHIFT 12 + +/* UBIFS padding byte pattern (must not be first or last byte of node magic) */ +#define UBIFS_PADDING_BYTE 0xCE + +/* Maximum possible key length */ +#define UBIFS_MAX_KEY_LEN 16 + +/* Key length ("simple" format) */ +#define UBIFS_SK_LEN 8 + +/* Minimum index tree fanout */ +#define UBIFS_MIN_FANOUT 3 + +/* Maximum number of levels in UBIFS indexing B-tree */ +#define UBIFS_MAX_LEVELS 512 + +/* Maximum amount of data attached to an inode in bytes */ +#define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE + +/* LEB Properties Tree fanout (must be power of 2) and fanout shift */ +#define UBIFS_LPT_FANOUT 4 +#define UBIFS_LPT_FANOUT_SHIFT 2 + +/* LEB Properties Tree bit field sizes */ +#define UBIFS_LPT_CRC_BITS 16 +#define UBIFS_LPT_CRC_BYTES 2 +#define UBIFS_LPT_TYPE_BITS 4 + +/* The key is always at the same position in all keyed nodes */ +#define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key) + +/* Garbage collector journal head number */ +#define UBIFS_GC_HEAD 0 +/* Base journal head number */ +#define UBIFS_BASE_HEAD 1 +/* Data journal head number */ +#define UBIFS_DATA_HEAD 2 + +/* + * LEB Properties Tree node types. + * + * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties) + * UBIFS_LPT_NNODE: LPT internal node + * UBIFS_LPT_LTAB: LPT's own lprops table + * UBIFS_LPT_LSAVE: LPT's save table (big model only) + * UBIFS_LPT_NODE_CNT: count of LPT node types + * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type + */ +enum { + UBIFS_LPT_PNODE, + UBIFS_LPT_NNODE, + UBIFS_LPT_LTAB, + UBIFS_LPT_LSAVE, + UBIFS_LPT_NODE_CNT, + UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1, +}; + +/* + * UBIFS inode types. + * + * UBIFS_ITYPE_REG: regular file + * UBIFS_ITYPE_DIR: directory + * UBIFS_ITYPE_LNK: soft link + * UBIFS_ITYPE_BLK: block device node + * UBIFS_ITYPE_CHR: character device node + * UBIFS_ITYPE_FIFO: fifo + * UBIFS_ITYPE_SOCK: socket + * UBIFS_ITYPES_CNT: count of supported file types + */ +enum { + UBIFS_ITYPE_REG, + UBIFS_ITYPE_DIR, + UBIFS_ITYPE_LNK, + UBIFS_ITYPE_BLK, + UBIFS_ITYPE_CHR, + UBIFS_ITYPE_FIFO, + UBIFS_ITYPE_SOCK, + UBIFS_ITYPES_CNT, +}; + +/* + * Supported key hash functions. + * + * UBIFS_KEY_HASH_R5: R5 hash + * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name + */ +enum { + UBIFS_KEY_HASH_R5, + UBIFS_KEY_HASH_TEST, +}; + +/* + * Supported key formats. + * + * UBIFS_SIMPLE_KEY_FMT: simple key format + */ +enum { + UBIFS_SIMPLE_KEY_FMT, +}; + +/* + * The simple key format uses 29 bits for storing UBIFS block number and hash + * value. + */ +#define UBIFS_S_KEY_BLOCK_BITS 29 +#define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF +#define UBIFS_S_KEY_HASH_BITS UBIFS_S_KEY_BLOCK_BITS +#define UBIFS_S_KEY_HASH_MASK UBIFS_S_KEY_BLOCK_MASK + +/* + * Key types. + * + * UBIFS_INO_KEY: inode node key + * UBIFS_DATA_KEY: data node key + * UBIFS_DENT_KEY: directory entry node key + * UBIFS_XENT_KEY: extended attribute entry key + * UBIFS_KEY_TYPES_CNT: number of supported key types + */ +enum { + UBIFS_INO_KEY, + UBIFS_DATA_KEY, + UBIFS_DENT_KEY, + UBIFS_XENT_KEY, + UBIFS_KEY_TYPES_CNT, +}; + +/* Count of LEBs reserved for the superblock area */ +#define UBIFS_SB_LEBS 1 +/* Count of LEBs reserved for the master area */ +#define UBIFS_MST_LEBS 2 + +/* First LEB of the superblock area */ +#define UBIFS_SB_LNUM 0 +/* First LEB of the master area */ +#define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS) +/* First LEB of the log area */ +#define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS) + +/* + * The below constants define the absolute minimum values for various UBIFS + * media areas. Many of them actually depend of flash geometry and the FS + * configuration (number of journal heads, orphan LEBs, etc). This means that + * the smallest volume size which can be used for UBIFS cannot be pre-defined + * by these constants. The file-system that meets the below limitation will not + * necessarily mount. UBIFS does run-time calculations and validates the FS + * size. + */ + +/* Minimum number of logical eraseblocks in the log */ +#define UBIFS_MIN_LOG_LEBS 2 +/* Minimum number of bud logical eraseblocks (one for each head) */ +#define UBIFS_MIN_BUD_LEBS 3 +/* Minimum number of journal logical eraseblocks */ +#define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS) +/* Minimum number of LPT area logical eraseblocks */ +#define UBIFS_MIN_LPT_LEBS 2 +/* Minimum number of orphan area logical eraseblocks */ +#define UBIFS_MIN_ORPH_LEBS 1 +/* + * Minimum number of main area logical eraseblocks (buds, 3 for the index, 1 + * for GC, 1 for deletions, and at least 1 for committed data). + */ +#define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 6) + +/* Minimum number of logical eraseblocks */ +#define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \ + UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \ + UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS) + +/* Node sizes (N.B. these are guaranteed to be multiples of 8) */ +#define UBIFS_CH_SZ sizeof(struct ubifs_ch) +#define UBIFS_INO_NODE_SZ sizeof(struct ubifs_ino_node) +#define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node) +#define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node) +#define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node) +#define UBIFS_PAD_NODE_SZ sizeof(struct ubifs_pad_node) +#define UBIFS_SB_NODE_SZ sizeof(struct ubifs_sb_node) +#define UBIFS_MST_NODE_SZ sizeof(struct ubifs_mst_node) +#define UBIFS_REF_NODE_SZ sizeof(struct ubifs_ref_node) +#define UBIFS_IDX_NODE_SZ sizeof(struct ubifs_idx_node) +#define UBIFS_CS_NODE_SZ sizeof(struct ubifs_cs_node) +#define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node) +#define UBIFS_AUTH_NODE_SZ sizeof(struct ubifs_auth_node) +#define UBIFS_SIG_NODE_SZ sizeof(struct ubifs_sig_node) + +/* Extended attribute entry nodes are identical to directory entry nodes */ +#define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ +/* Only this does not have to be multiple of 8 bytes */ +#define UBIFS_BRANCH_SZ sizeof(struct ubifs_branch) + +/* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */ +#define UBIFS_MAX_DATA_NODE_SZ (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE) +#define UBIFS_MAX_INO_NODE_SZ (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA) +#define UBIFS_MAX_DENT_NODE_SZ (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1) +#define UBIFS_MAX_XENT_NODE_SZ UBIFS_MAX_DENT_NODE_SZ + +/* The largest UBIFS node */ +#define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ + +/* The maxmimum size of a hash, enough for sha512 */ +#define UBIFS_MAX_HASH_LEN 64 + +/* The maxmimum size of a hmac, enough for hmac(sha512) */ +#define UBIFS_MAX_HMAC_LEN 64 + +/* + * xattr name of UBIFS encryption context, we don't use a prefix + * nor a long name to not waste space on the flash. + */ +#define UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT "c" + +/* Type field in ubifs_sig_node */ +#define UBIFS_SIGNATURE_TYPE_PKCS7 1 + +/* + * On-flash inode flags. + * + * UBIFS_COMPR_FL: use compression for this inode + * UBIFS_SYNC_FL: I/O on this inode has to be synchronous + * UBIFS_IMMUTABLE_FL: inode is immutable + * UBIFS_APPEND_FL: writes to the inode may only append data + * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous + * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value + * UBIFS_CRYPT_FL: use encryption for this inode + * + * Note, these are on-flash flags which correspond to ioctl flags + * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not + * have to be the same. + */ +enum { + UBIFS_COMPR_FL = 0x01, + UBIFS_SYNC_FL = 0x02, + UBIFS_IMMUTABLE_FL = 0x04, + UBIFS_APPEND_FL = 0x08, + UBIFS_DIRSYNC_FL = 0x10, + UBIFS_XATTR_FL = 0x20, + UBIFS_CRYPT_FL = 0x40, +}; + +/* Inode flag bits used by UBIFS */ +#define UBIFS_FL_MASK 0x0000001F + +/* + * UBIFS compression algorithms. + * + * UBIFS_COMPR_NONE: no compression + * UBIFS_COMPR_LZO: LZO compression + * UBIFS_COMPR_ZLIB: ZLIB compression + * UBIFS_COMPR_ZSTD: ZSTD compression + * UBIFS_COMPR_TYPES_CNT: count of supported compression types + */ +enum { + UBIFS_COMPR_NONE, + UBIFS_COMPR_LZO, + UBIFS_COMPR_ZLIB, + UBIFS_COMPR_ZSTD, + UBIFS_COMPR_TYPES_CNT, +}; + +/* + * UBIFS node types. + * + * UBIFS_INO_NODE: inode node + * UBIFS_DATA_NODE: data node + * UBIFS_DENT_NODE: directory entry node + * UBIFS_XENT_NODE: extended attribute node + * UBIFS_TRUN_NODE: truncation node + * UBIFS_PAD_NODE: padding node + * UBIFS_SB_NODE: superblock node + * UBIFS_MST_NODE: master node + * UBIFS_REF_NODE: LEB reference node + * UBIFS_IDX_NODE: index node + * UBIFS_CS_NODE: commit start node + * UBIFS_ORPH_NODE: orphan node + * UBIFS_AUTH_NODE: authentication node + * UBIFS_SIG_NODE: signature node + * UBIFS_NODE_TYPES_CNT: count of supported node types + * + * Note, we index arrays by these numbers, so keep them low and contiguous. + * Node type constants for inodes, direntries and so on have to be the same as + * corresponding key type constants. + */ +enum { + UBIFS_INO_NODE, + UBIFS_DATA_NODE, + UBIFS_DENT_NODE, + UBIFS_XENT_NODE, + UBIFS_TRUN_NODE, + UBIFS_PAD_NODE, + UBIFS_SB_NODE, + UBIFS_MST_NODE, + UBIFS_REF_NODE, + UBIFS_IDX_NODE, + UBIFS_CS_NODE, + UBIFS_ORPH_NODE, + UBIFS_AUTH_NODE, + UBIFS_SIG_NODE, + UBIFS_NODE_TYPES_CNT, +}; + +/* + * Master node flags. + * + * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty + * UBIFS_MST_NO_ORPHS: no orphan inodes present + * UBIFS_MST_RCVRY: written by recovery + */ +enum { + UBIFS_MST_DIRTY = 1, + UBIFS_MST_NO_ORPHS = 2, + UBIFS_MST_RCVRY = 4, +}; + +/* + * Node group type (used by recovery to recover whole group or none). + * + * UBIFS_NO_NODE_GROUP: this node is not part of a group + * UBIFS_IN_NODE_GROUP: this node is a part of a group + * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group + */ +enum { + UBIFS_NO_NODE_GROUP = 0, + UBIFS_IN_NODE_GROUP, + UBIFS_LAST_OF_NODE_GROUP, +}; + +/* + * Superblock flags. + * + * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set + * UBIFS_FLG_SPACE_FIXUP: first-mount "fixup" of free space within LEBs needed + * UBIFS_FLG_DOUBLE_HASH: store a 32bit cookie in directory entry nodes to + * support 64bit cookies for lookups by hash + * UBIFS_FLG_ENCRYPTION: this filesystem contains encrypted files + * UBIFS_FLG_AUTHENTICATION: this filesystem contains hashes for authentication + */ +enum { + UBIFS_FLG_BIGLPT = 0x02, + UBIFS_FLG_SPACE_FIXUP = 0x04, + UBIFS_FLG_DOUBLE_HASH = 0x08, + UBIFS_FLG_ENCRYPTION = 0x10, + UBIFS_FLG_AUTHENTICATION = 0x20, +}; + +#define UBIFS_FLG_MASK (UBIFS_FLG_BIGLPT | UBIFS_FLG_SPACE_FIXUP | \ + UBIFS_FLG_DOUBLE_HASH | UBIFS_FLG_ENCRYPTION | \ + UBIFS_FLG_AUTHENTICATION) + +/** + * struct ubifs_ch - common header node. + * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC) + * @crc: CRC-32 checksum of the node header + * @sqnum: sequence number + * @len: full node length + * @node_type: node type + * @group_type: node group type + * @padding: reserved for future, zeroes + * + * Every UBIFS node starts with this common part. If the node has a key, the + * key always goes next. + */ +struct ubifs_ch { + __le32 magic; + __le32 crc; + __le64 sqnum; + __le32 len; + __u8 node_type; + __u8 group_type; + __u8 padding[2]; +} __attribute__ ((packed)); + +/** + * union ubifs_dev_desc - device node descriptor. + * @new: new type device descriptor + * @huge: huge type device descriptor + * + * This data structure describes major/minor numbers of a device node. In an + * inode is a device node then its data contains an object of this type. UBIFS + * uses standard Linux "new" and "huge" device node encodings. + */ +union ubifs_dev_desc { + __le32 new; + __le64 huge; +} __attribute__ ((packed)); + +/** + * struct ubifs_ino_node - inode node. + * @ch: common header + * @key: node key + * @creat_sqnum: sequence number at time of creation + * @size: inode size in bytes (amount of uncompressed data) + * @atime_sec: access time seconds + * @ctime_sec: creation time seconds + * @mtime_sec: modification time seconds + * @atime_nsec: access time nanoseconds + * @ctime_nsec: creation time nanoseconds + * @mtime_nsec: modification time nanoseconds + * @nlink: number of hard links + * @uid: owner ID + * @gid: group ID + * @mode: access flags + * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc) + * @data_len: inode data length + * @xattr_cnt: count of extended attributes this inode has + * @xattr_size: summarized size of all extended attributes in bytes + * @padding1: reserved for future, zeroes + * @xattr_names: sum of lengths of all extended attribute names belonging to + * this inode + * @compr_type: compression type used for this inode + * @padding2: reserved for future, zeroes + * @data: data attached to the inode + * + * Note, even though inode compression type is defined by @compr_type, some + * nodes of this inode may be compressed with different compressor - this + * happens if compression type is changed while the inode already has data + * nodes. But @compr_type will be use for further writes to the inode. + * + * Note, do not forget to amend 'zero_ino_node_unused()' function when changing + * the padding fields. + */ +struct ubifs_ino_node { + struct ubifs_ch ch; + __u8 key[UBIFS_MAX_KEY_LEN]; + __le64 creat_sqnum; + __le64 size; + __le64 atime_sec; + __le64 ctime_sec; + __le64 mtime_sec; + __le32 atime_nsec; + __le32 ctime_nsec; + __le32 mtime_nsec; + __le32 nlink; + __le32 uid; + __le32 gid; + __le32 mode; + __le32 flags; + __le32 data_len; + __le32 xattr_cnt; + __le32 xattr_size; + __u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */ + __le32 xattr_names; + __le16 compr_type; + __u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */ + __u8 data[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_dent_node - directory entry node. + * @ch: common header + * @key: node key + * @inum: target inode number + * @padding1: reserved for future, zeroes + * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc) + * @nlen: name length + * @cookie: A 32bits random number, used to construct a 64bits + * identifier. + * @name: zero-terminated name + * + * Note, do not forget to amend 'zero_dent_node_unused()' function when + * changing the padding fields. + */ +struct ubifs_dent_node { + struct ubifs_ch ch; + __u8 key[UBIFS_MAX_KEY_LEN]; + __le64 inum; + __u8 padding1; + __u8 type; + __le16 nlen; + __le32 cookie; + __u8 name[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_data_node - data node. + * @ch: common header + * @key: node key + * @size: uncompressed data size in bytes + * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc) + * @compr_size: compressed data size in bytes, only valid when data is encrypted + * @data: data + * + */ +struct ubifs_data_node { + struct ubifs_ch ch; + __u8 key[UBIFS_MAX_KEY_LEN]; + __le32 size; + __le16 compr_type; + __le16 compr_size; + __u8 data[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_trun_node - truncation node. + * @ch: common header + * @inum: truncated inode number + * @padding: reserved for future, zeroes + * @old_size: size before truncation + * @new_size: size after truncation + * + * This node exists only in the journal and never goes to the main area. Note, + * do not forget to amend 'zero_trun_node_unused()' function when changing the + * padding fields. + */ +struct ubifs_trun_node { + struct ubifs_ch ch; + __le32 inum; + __u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */ + __le64 old_size; + __le64 new_size; +} __attribute__ ((packed)); + +/** + * struct ubifs_pad_node - padding node. + * @ch: common header + * @pad_len: how many bytes after this node are unused (because padded) + * @padding: reserved for future, zeroes + */ +struct ubifs_pad_node { + struct ubifs_ch ch; + __le32 pad_len; +} __attribute__ ((packed)); + +/** + * struct ubifs_sb_node - superblock node. + * @ch: common header + * @padding: reserved for future, zeroes + * @key_hash: type of hash function used in keys + * @key_fmt: format of the key + * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc) + * @min_io_size: minimal input/output unit size + * @leb_size: logical eraseblock size in bytes + * @leb_cnt: count of LEBs used by file-system + * @max_leb_cnt: maximum count of LEBs used by file-system + * @max_bud_bytes: maximum amount of data stored in buds + * @log_lebs: log size in logical eraseblocks + * @lpt_lebs: number of LEBs used for lprops table + * @orph_lebs: number of LEBs used for recording orphans + * @jhead_cnt: count of journal heads + * @fanout: tree fanout (max. number of links per indexing node) + * @lsave_cnt: number of LEB numbers in LPT's save table + * @fmt_version: UBIFS on-flash format version + * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc) + * @padding1: reserved for future, zeroes + * @rp_uid: reserve pool UID + * @rp_gid: reserve pool GID + * @rp_size: size of the reserved pool in bytes + * @padding2: reserved for future, zeroes + * @time_gran: time granularity in nanoseconds + * @uuid: UUID generated when the file system image was created + * @ro_compat_version: UBIFS R/O compatibility version + * @hmac: HMAC to authenticate the superblock node + * @hmac_wkm: HMAC of a well known message (the string "UBIFS") as a convenience + * to the user to check if the correct key is passed. + * @hash_algo: The hash algo used for this filesystem (one of enum hash_algo) + * @hash_mst: hash of the master node, only valid for signed images in which the + * master node does not contain a hmac + */ +struct ubifs_sb_node { + struct ubifs_ch ch; + __u8 padding[2]; + __u8 key_hash; + __u8 key_fmt; + __le32 flags; + __le32 min_io_size; + __le32 leb_size; + __le32 leb_cnt; + __le32 max_leb_cnt; + __le64 max_bud_bytes; + __le32 log_lebs; + __le32 lpt_lebs; + __le32 orph_lebs; + __le32 jhead_cnt; + __le32 fanout; + __le32 lsave_cnt; + __le32 fmt_version; + __le16 default_compr; + __u8 padding1[2]; + __le32 rp_uid; + __le32 rp_gid; + __le64 rp_size; + __le32 time_gran; + __u8 uuid[16]; + __le32 ro_compat_version; + __u8 hmac[UBIFS_MAX_HMAC_LEN]; + __u8 hmac_wkm[UBIFS_MAX_HMAC_LEN]; + __le16 hash_algo; + __u8 hash_mst[UBIFS_MAX_HASH_LEN]; + __u8 padding2[3774]; +} __attribute__ ((packed)); + +/** + * struct ubifs_mst_node - master node. + * @ch: common header + * @highest_inum: highest inode number in the committed index + * @cmt_no: commit number + * @flags: various flags (%UBIFS_MST_DIRTY, etc) + * @log_lnum: start of the log + * @root_lnum: LEB number of the root indexing node + * @root_offs: offset within @root_lnum + * @root_len: root indexing node length + * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was + * not reserved and should be reserved on mount) + * @ihead_lnum: LEB number of index head + * @ihead_offs: offset of index head + * @index_size: size of index on flash + * @total_free: total free space in bytes + * @total_dirty: total dirty space in bytes + * @total_used: total used space in bytes (includes only data LEBs) + * @total_dead: total dead space in bytes (includes only data LEBs) + * @total_dark: total dark space in bytes (includes only data LEBs) + * @lpt_lnum: LEB number of LPT root nnode + * @lpt_offs: offset of LPT root nnode + * @nhead_lnum: LEB number of LPT head + * @nhead_offs: offset of LPT head + * @ltab_lnum: LEB number of LPT's own lprops table + * @ltab_offs: offset of LPT's own lprops table + * @lsave_lnum: LEB number of LPT's save table (big model only) + * @lsave_offs: offset of LPT's save table (big model only) + * @lscan_lnum: LEB number of last LPT scan + * @empty_lebs: number of empty logical eraseblocks + * @idx_lebs: number of indexing logical eraseblocks + * @leb_cnt: count of LEBs used by file-system + * @hash_root_idx: the hash of the root index node + * @hash_lpt: the hash of the LPT + * @hmac: HMAC to authenticate the master node + * @padding: reserved for future, zeroes + */ +struct ubifs_mst_node { + struct ubifs_ch ch; + __le64 highest_inum; + __le64 cmt_no; + __le32 flags; + __le32 log_lnum; + __le32 root_lnum; + __le32 root_offs; + __le32 root_len; + __le32 gc_lnum; + __le32 ihead_lnum; + __le32 ihead_offs; + __le64 index_size; + __le64 total_free; + __le64 total_dirty; + __le64 total_used; + __le64 total_dead; + __le64 total_dark; + __le32 lpt_lnum; + __le32 lpt_offs; + __le32 nhead_lnum; + __le32 nhead_offs; + __le32 ltab_lnum; + __le32 ltab_offs; + __le32 lsave_lnum; + __le32 lsave_offs; + __le32 lscan_lnum; + __le32 empty_lebs; + __le32 idx_lebs; + __le32 leb_cnt; + __u8 hash_root_idx[UBIFS_MAX_HASH_LEN]; + __u8 hash_lpt[UBIFS_MAX_HASH_LEN]; + __u8 hmac[UBIFS_MAX_HMAC_LEN]; + __u8 padding[152]; +} __attribute__ ((packed)); + +/** + * struct ubifs_ref_node - logical eraseblock reference node. + * @ch: common header + * @lnum: the referred logical eraseblock number + * @offs: start offset in the referred LEB + * @jhead: journal head number + * @padding: reserved for future, zeroes + */ +struct ubifs_ref_node { + struct ubifs_ch ch; + __le32 lnum; + __le32 offs; + __le32 jhead; + __u8 padding[28]; +} __attribute__ ((packed)); + +/** + * struct ubifs_auth_node - node for authenticating other nodes + * @ch: common header + * @hmac: The HMAC + */ +struct ubifs_auth_node { + struct ubifs_ch ch; + __u8 hmac[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_sig_node - node for signing other nodes + * @ch: common header + * @type: type of the signature, currently only UBIFS_SIGNATURE_TYPE_PKCS7 + * supported + * @len: The length of the signature data + * @padding: reserved for future, zeroes + * @sig: The signature data + */ +struct ubifs_sig_node { + struct ubifs_ch ch; + __le32 type; + __le32 len; + __u8 padding[32]; + __u8 sig[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_branch - key/reference/length branch + * @lnum: LEB number of the target node + * @offs: offset within @lnum + * @len: target node length + * @key: key + * + * In an authenticated UBIFS we have the hash of the referenced node after @key. + * This can't be added to the struct type definition because @key is a + * dynamically sized element already. + */ +struct ubifs_branch { + __le32 lnum; + __le32 offs; + __le32 len; + __u8 key[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_idx_node - indexing node. + * @ch: common header + * @child_cnt: number of child index nodes + * @level: tree level + * @branches: LEB number / offset / length / key branches + */ +struct ubifs_idx_node { + struct ubifs_ch ch; + __le16 child_cnt; + __le16 level; + __u8 branches[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_cs_node - commit start node. + * @ch: common header + * @cmt_no: commit number + */ +struct ubifs_cs_node { + struct ubifs_ch ch; + __le64 cmt_no; +} __attribute__ ((packed)); + +/** + * struct ubifs_orph_node - orphan node. + * @ch: common header + * @cmt_no: commit number (also top bit is set on the last node of the commit) + * @inos: inode numbers of orphans + */ +struct ubifs_orph_node { + struct ubifs_ch ch; + __le64 cmt_no; + __le64 inos[]; +} __attribute__ ((packed)); + +#endif /* __UBIFS_MEDIA_H__ */ diff --git a/ubifs-utils/libubifs/ubifs.h b/ubifs-utils/libubifs/ubifs.h new file mode 100644 index 0000000..1c7bc7b --- /dev/null +++ b/ubifs-utils/libubifs/ubifs.h @@ -0,0 +1,1925 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +#ifndef __UBIFS_H__ +#define __UBIFS_H__ + +#include <fcntl.h> +#include <string.h> + +#include "linux_types.h" +#include "list.h" +#include "rbtree.h" +#include "spinlock.h" +#include "mutex.h" +#include "rwsem.h" +#include "atomic.h" +#include "libubi.h" +#include "ubifs-media.h" + +/* Number of UBIFS blocks per VFS page */ +#define UBIFS_BLOCKS_PER_PAGE (PAGE_SIZE / UBIFS_BLOCK_SIZE) +#define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_SHIFT - UBIFS_BLOCK_SHIFT) + +/* "File system end of life" sequence number watermark */ +#define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL +#define SQNUM_WATERMARK 0xFFFFFFFFFF000000ULL + +/* + * Minimum amount of LEBs reserved for the index. At present the index needs at + * least 2 LEBs: one for the index head and one for in-the-gaps method (which + * currently does not cater for the index head and so excludes it from + * consideration). + */ +#define MIN_INDEX_LEBS 2 + +/* Maximum logical eraseblock size in bytes */ +#define UBIFS_MAX_LEB_SZ (2*1024*1024) + +/* Minimum amount of data UBIFS writes to the flash */ +#define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8) + +/* + * Currently we do not support inode number overlapping and re-using, so this + * watermark defines dangerous inode number level. This should be fixed later, + * although it is difficult to exceed current limit. Another option is to use + * 64-bit inode numbers, but this means more overhead. + */ +#define INUM_WARN_WATERMARK 0xFFF00000 +#define INUM_WATERMARK 0xFFFFFF00 + +/* Maximum number of entries in each LPT (LEB category) heap */ +#define LPT_HEAP_SZ 256 + +/* Maximum possible inode number (only 32-bit inodes are supported now) */ +#define MAX_INUM 0xFFFFFFFF + +/* Number of non-data journal heads */ +#define NONDATA_JHEADS_CNT 2 + +/* Shorter names for journal head numbers for internal usage */ +#define GCHD UBIFS_GC_HEAD +#define BASEHD UBIFS_BASE_HEAD +#define DATAHD UBIFS_DATA_HEAD + +/* 'No change' value for 'ubifs_change_lp()' */ +#define LPROPS_NC 0x80000001 + +/* + * There is no notion of truncation key because truncation nodes do not exist + * in TNC. However, when replaying, it is handy to introduce fake "truncation" + * keys for truncation nodes because the code becomes simpler. So we define + * %UBIFS_TRUN_KEY type. + * + * But otherwise, out of the journal reply scope, the truncation keys are + * invalid. + */ +#define UBIFS_TRUN_KEY UBIFS_KEY_TYPES_CNT +#define UBIFS_INVALID_KEY UBIFS_KEY_TYPES_CNT + +/* + * How much a directory entry/extended attribute entry adds to the parent/host + * inode. + */ +#define CALC_DENT_SIZE(name_len) ALIGN(UBIFS_DENT_NODE_SZ + (name_len) + 1, 8) + +/* How much an extended attribute adds to the host inode */ +#define CALC_XATTR_BYTES(data_len) ALIGN(UBIFS_INO_NODE_SZ + (data_len) + 1, 8) + +/* Maximum expected tree height for use by bottom_up_buf */ +#define BOTTOM_UP_HEIGHT 64 + +#define UBIFS_HASH_ARR_SZ UBIFS_MAX_HASH_LEN +#define UBIFS_HMAC_ARR_SZ UBIFS_MAX_HMAC_LEN + +/* + * Znode flags (actually, bit numbers which store the flags). + * + * DIRTY_ZNODE: znode is dirty + * COW_ZNODE: znode is being committed and a new instance of this znode has to + * be created before changing this znode + * OBSOLETE_ZNODE: znode is obsolete, which means it was deleted, but it is + * still in the commit list and the ongoing commit operation + * will commit it, and delete this znode after it is done + */ +enum { + DIRTY_ZNODE = 0, + COW_ZNODE = 1, + OBSOLETE_ZNODE = 2, +}; + +/* + * Commit states. + * + * COMMIT_RESTING: commit is not wanted + * COMMIT_BACKGROUND: background commit has been requested + * COMMIT_REQUIRED: commit is required + * COMMIT_RUNNING_BACKGROUND: background commit is running + * COMMIT_RUNNING_REQUIRED: commit is running and it is required + * COMMIT_BROKEN: commit failed + */ +enum { + COMMIT_RESTING = 0, + COMMIT_BACKGROUND, + COMMIT_REQUIRED, + COMMIT_RUNNING_BACKGROUND, + COMMIT_RUNNING_REQUIRED, + COMMIT_BROKEN, +}; + +/* + * 'ubifs_scan_a_node()' return values. + * + * SCANNED_GARBAGE: scanned garbage + * SCANNED_EMPTY_SPACE: scanned empty space + * SCANNED_A_NODE: scanned a valid node + * SCANNED_A_CORRUPT_NODE: scanned a corrupted node + * SCANNED_A_BAD_PAD_NODE: scanned a padding node with invalid pad length + * + * Greater than zero means: 'scanned that number of padding bytes' + */ +enum { + SCANNED_GARBAGE = 0, + SCANNED_EMPTY_SPACE = -1, + SCANNED_A_NODE = -2, + SCANNED_A_CORRUPT_NODE = -3, + SCANNED_A_BAD_PAD_NODE = -4, +}; + +/* + * LPT cnode flag bits. + * + * DIRTY_CNODE: cnode is dirty + * OBSOLETE_CNODE: cnode is being committed and has been copied (or deleted), + * so it can (and must) be freed when the commit is finished + * COW_CNODE: cnode is being committed and must be copied before writing + */ +enum { + DIRTY_CNODE = 0, + OBSOLETE_CNODE = 1, + COW_CNODE = 2, +}; + +/* + * Dirty flag bits (lpt_drty_flgs) for LPT special nodes. + * + * LTAB_DIRTY: ltab node is dirty + * LSAVE_DIRTY: lsave node is dirty + */ +enum { + LTAB_DIRTY = 1, + LSAVE_DIRTY = 2, +}; + +/* + * Return codes used by the garbage collector. + * @LEB_FREED: the logical eraseblock was freed and is ready to use + * @LEB_FREED_IDX: indexing LEB was freed and can be used only after the commit + * @LEB_RETAINED: the logical eraseblock was freed and retained for GC purposes + */ +enum { + LEB_FREED, + LEB_FREED_IDX, + LEB_RETAINED, +}; + +/** + * struct ubifs_old_idx - index node obsoleted since last commit start. + * @rb: rb-tree node + * @lnum: LEB number of obsoleted index node + * @offs: offset of obsoleted index node + */ +struct ubifs_old_idx { + struct rb_node rb; + int lnum; + int offs; +}; + +/* The below union makes it easier to deal with keys */ +union ubifs_key { + uint8_t u8[UBIFS_SK_LEN]; + uint32_t u32[UBIFS_SK_LEN/4]; + uint64_t u64[UBIFS_SK_LEN/8]; + __le32 j32[UBIFS_SK_LEN/4]; +}; + +/** + * struct ubifs_scan_node - UBIFS scanned node information. + * @list: list of scanned nodes + * @key: key of node scanned (if it has one) + * @sqnum: sequence number + * @type: type of node scanned + * @offs: offset with LEB of node scanned + * @len: length of node scanned + * @node: raw node + */ +struct ubifs_scan_node { + struct list_head list; + union ubifs_key key; + unsigned long long sqnum; + int type; + int offs; + int len; + void *node; +}; + +/** + * struct ubifs_scan_leb - UBIFS scanned LEB information. + * @lnum: logical eraseblock number + * @nodes_cnt: number of nodes scanned + * @nodes: list of struct ubifs_scan_node + * @endpt: end point (and therefore the start of empty space) + * @buf: buffer containing entire LEB scanned + */ +struct ubifs_scan_leb { + int lnum; + int nodes_cnt; + struct list_head nodes; + int endpt; + void *buf; +}; + +/** + * struct ubifs_gced_idx_leb - garbage-collected indexing LEB. + * @list: list + * @lnum: LEB number + * @unmap: OK to unmap this LEB + * + * This data structure is used to temporary store garbage-collected indexing + * LEBs - they are not released immediately, but only after the next commit. + * This is needed to guarantee recoverability. + */ +struct ubifs_gced_idx_leb { + struct list_head list; + int lnum; + int unmap; +}; + +/** + * struct inode - inode description. + * @uid: owner ID + * @gid: group ID + * @mode: access flags + * @nlink: number of hard links + * @inum: inode number + * @atime_sec: access time seconds + * @ctime_sec: creation time seconds + * @mtime_sec: modification time seconds + * @atime_nsec: access time nanoseconds + * @ctime_nsec: creation time nanoseconds + * @mtime_nsec: modification time nanoseconds + */ +struct inode { + unsigned int uid; + unsigned int gid; + unsigned int mode; + unsigned int nlink; + ino_t inum; + unsigned long long atime_sec; + unsigned long long ctime_sec; + unsigned long long mtime_sec; + unsigned int atime_nsec; + unsigned int ctime_nsec; + unsigned int mtime_nsec; +}; + +/** + * struct ubifs_inode - UBIFS in-memory inode description. + * @vfs_inode: VFS inode description object + * @creat_sqnum: sequence number at time of creation + * @xattr_size: summarized size of all extended attributes in bytes + * @xattr_cnt: count of extended attributes this inode has + * @xattr_names: sum of lengths of all extended attribute names belonging to + * this inode + * @ui_size: inode size used by UBIFS when writing to flash + * @flags: inode flags (@UBIFS_COMPR_FL, etc) + * @compr_type: default compression type used for this inode + * @data_len: length of the data attached to the inode + * @data: inode's data + */ +struct ubifs_inode { + struct inode vfs_inode; + unsigned long long creat_sqnum; + unsigned int xattr_size; + unsigned int xattr_cnt; + unsigned int xattr_names; + unsigned int compr_type:2; + loff_t ui_size; + int flags; + int data_len; + void *data; +}; + +/** + * struct ubifs_unclean_leb - records a LEB recovered under read-only mode. + * @list: list + * @lnum: LEB number of recovered LEB + * @endpt: offset where recovery ended + * + * This structure records a LEB identified during recovery that needs to be + * cleaned but was not because UBIFS was mounted read-only. The information + * is used to clean the LEB when remounting to read-write mode. + */ +struct ubifs_unclean_leb { + struct list_head list; + int lnum; + int endpt; +}; + +/* + * LEB properties flags. + * + * LPROPS_UNCAT: not categorized + * LPROPS_DIRTY: dirty > free, dirty >= @c->dead_wm, not index + * LPROPS_DIRTY_IDX: dirty + free > @c->min_idx_node_sze and index + * LPROPS_FREE: free > 0, dirty < @c->dead_wm, not empty, not index + * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs + * LPROPS_EMPTY: LEB is empty, not taken + * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken + * LPROPS_FRDI_IDX: free + dirty == leb_size and index, may be taken + * LPROPS_CAT_MASK: mask for the LEB categories above + * LPROPS_TAKEN: LEB was taken (this flag is not saved on the media) + * LPROPS_INDEX: LEB contains indexing nodes (this flag also exists on flash) + */ +enum { + LPROPS_UNCAT = 0, + LPROPS_DIRTY = 1, + LPROPS_DIRTY_IDX = 2, + LPROPS_FREE = 3, + LPROPS_HEAP_CNT = 3, + LPROPS_EMPTY = 4, + LPROPS_FREEABLE = 5, + LPROPS_FRDI_IDX = 6, + LPROPS_CAT_MASK = 15, + LPROPS_TAKEN = 16, + LPROPS_INDEX = 32, +}; + +/** + * struct ubifs_lprops - logical eraseblock properties. + * @free: amount of free space in bytes + * @dirty: amount of dirty space in bytes + * @flags: LEB properties flags (see above) + * @lnum: LEB number + * @end: the end postition of LEB calculated by the last node + * @used: amount of used space in bytes + * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE) + * @hpos: heap position in heap of same-category lprops (other categories) + */ +struct ubifs_lprops { + int free; + int dirty; + int flags; + int lnum; + int end; + int used; + union { + struct list_head list; + int hpos; + }; +}; + +/** + * struct ubifs_lpt_lprops - LPT logical eraseblock properties. + * @free: amount of free space in bytes + * @dirty: amount of dirty space in bytes + * @tgc: trivial GC flag (1 => unmap after commit end) + * @cmt: commit flag (1 => reserved for commit) + */ +struct ubifs_lpt_lprops { + int free; + int dirty; + unsigned tgc:1; + unsigned cmt:1; +}; + +/** + * struct ubifs_lp_stats - statistics of eraseblocks in the main area. + * @empty_lebs: number of empty LEBs + * @taken_empty_lebs: number of taken LEBs + * @idx_lebs: number of indexing LEBs + * @total_free: total free space in bytes (includes all LEBs) + * @total_dirty: total dirty space in bytes (includes all LEBs) + * @total_used: total used space in bytes (does not include index LEBs) + * @total_dead: total dead space in bytes (does not include index LEBs) + * @total_dark: total dark space in bytes (does not include index LEBs) + * + * The @taken_empty_lebs field counts the LEBs that are in the transient state + * of having been "taken" for use but not yet written to. @taken_empty_lebs is + * needed to account correctly for @gc_lnum, otherwise @empty_lebs could be + * used by itself (in which case 'unused_lebs' would be a better name). In the + * case of @gc_lnum, it is "taken" at mount time or whenever a LEB is retained + * by GC, but unlike other empty LEBs that are "taken", it may not be written + * straight away (i.e. before the next commit start or unmount), so either + * @gc_lnum must be specially accounted for, or the current approach followed + * i.e. count it under @taken_empty_lebs. + * + * @empty_lebs includes @taken_empty_lebs. + * + * @total_used, @total_dead and @total_dark fields do not account indexing + * LEBs. + */ +struct ubifs_lp_stats { + int empty_lebs; + int taken_empty_lebs; + int idx_lebs; + long long total_free; + long long total_dirty; + long long total_used; + long long total_dead; + long long total_dark; +}; + +struct ubifs_nnode; + +/** + * struct ubifs_cnode - LEB Properties Tree common node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (zero for pnodes, greater than zero for nnodes) + * @num: node number + */ +struct ubifs_cnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; +}; + +/** + * struct ubifs_pnode - LEB Properties Tree leaf node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (always zero for pnodes) + * @num: node number + * @lprops: LEB properties array + */ +struct ubifs_pnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; + struct ubifs_lprops lprops[UBIFS_LPT_FANOUT]; +}; + +/** + * struct ubifs_nbranch - LEB Properties Tree internal node branch. + * @lnum: LEB number of child + * @offs: offset of child + * @nnode: nnode child + * @pnode: pnode child + * @cnode: cnode child + */ +struct ubifs_nbranch { + int lnum; + int offs; + union { + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + struct ubifs_cnode *cnode; + }; +}; + +/** + * struct ubifs_nnode - LEB Properties Tree internal node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (always greater than zero for nnodes) + * @num: node number + * @nbranch: branches to child nodes + */ +struct ubifs_nnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; + struct ubifs_nbranch nbranch[UBIFS_LPT_FANOUT]; +}; + +/** + * struct ubifs_lpt_heap - heap of categorized lprops. + * @arr: heap array + * @cnt: number in heap + * @max_cnt: maximum number allowed in heap + * + * There are %LPROPS_HEAP_CNT heaps. + */ +struct ubifs_lpt_heap { + struct ubifs_lprops **arr; + int cnt; + int max_cnt; +}; + +/* + * Return codes for LPT scan callback function. + * + * LPT_SCAN_CONTINUE: continue scanning + * LPT_SCAN_ADD: add the LEB properties scanned to the tree in memory + * LPT_SCAN_STOP: stop scanning + */ +enum { + LPT_SCAN_CONTINUE = 0, + LPT_SCAN_ADD = 1, + LPT_SCAN_STOP = 2, +}; + +struct ubifs_info; + +/* Callback used by the 'ubifs_lpt_scan_nolock()' function */ +typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c, + const struct ubifs_lprops *lprops, + int in_tree, void *data); + +/** + * struct ubifs_wbuf - UBIFS write-buffer. + * @c: UBIFS file-system description object + * @buf: write-buffer (of min. flash I/O unit size) + * @lnum: logical eraseblock number the write-buffer points to + * @offs: write-buffer offset in this logical eraseblock + * @avail: number of bytes available in the write-buffer + * @used: number of used bytes in the write-buffer + * @size: write-buffer size (in [@c->min_io_size, @c->max_write_size] range) + * @jhead: journal head the mutex belongs to (note, needed only to shut lockdep + * up by 'mutex_lock_nested()). + * @sync_callback: write-buffer synchronization callback + * @io_mutex: serializes write-buffer I/O + * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes + * fields + * @next_ino: points to the next position of the following inode number + * @inodes: stores the inode numbers of the nodes which are in wbuf + * + * The write-buffer synchronization callback is called when the write-buffer is + * synchronized in order to notify how much space was wasted due to + * write-buffer padding and how much free space is left in the LEB. + * + * Note: the fields @buf, @lnum, @offs, @avail and @used can be read under + * spin-lock or mutex because they are written under both mutex and spin-lock. + * @buf is appended to under mutex but overwritten under both mutex and + * spin-lock. Thus the data between @buf and @buf + @used can be read under + * spinlock. + */ +struct ubifs_wbuf { + struct ubifs_info *c; + void *buf; + int lnum; + int offs; + int avail; + int used; + int size; + int jhead; + int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad); + struct mutex io_mutex; + spinlock_t lock; + int next_ino; + ino_t *inodes; +}; + +/** + * struct ubifs_bud - bud logical eraseblock. + * @lnum: logical eraseblock number + * @start: where the (uncommitted) bud data starts + * @jhead: journal head number this bud belongs to + * @list: link in the list buds belonging to the same journal head + * @rb: link in the tree of all buds + * @log_hash: the log hash from the commit start node up to this bud + */ +struct ubifs_bud { + int lnum; + int start; + int jhead; + struct list_head list; + struct rb_node rb; + struct shash_desc *log_hash; +}; + +/** + * struct ubifs_jhead - journal head. + * @wbuf: head's write-buffer + * @buds_list: list of bud LEBs belonging to this journal head + * @grouped: non-zero if UBIFS groups nodes when writing to this journal head + * @log_hash: the log hash from the commit start node up to this journal head + * + * Note, the @buds list is protected by the @c->buds_lock. + */ +struct ubifs_jhead { + struct ubifs_wbuf wbuf; + struct list_head buds_list; + unsigned int grouped:1; + struct shash_desc *log_hash; +}; + +/** + * struct ubifs_zbranch - key/coordinate/length branch stored in znodes. + * @key: key + * @znode: znode address in memory + * @lnum: LEB number of the target node (indexing node or data node) + * @offs: target node offset within @lnum + * @len: target node length + * @hash: the hash of the target node + */ +struct ubifs_zbranch { + union ubifs_key key; + union { + struct ubifs_znode *znode; + void *leaf; + }; + int lnum; + int offs; + int len; + u8 hash[UBIFS_HASH_ARR_SZ]; +}; + +/** + * struct ubifs_znode - in-memory representation of an indexing node. + * @parent: parent znode or NULL if it is the root + * @cnext: next znode to commit + * @cparent: parent node for this commit + * @ciip: index in cparent's zbranch array + * @flags: znode flags (%DIRTY_ZNODE, %COW_ZNODE or %OBSOLETE_ZNODE) + * @time: last access time (seconds) + * @level: level of the entry in the TNC tree + * @child_cnt: count of child znodes + * @iip: index in parent's zbranch array + * @alt: lower bound of key range has altered i.e. child inserted at slot 0 + * @lnum: LEB number of the corresponding indexing node + * @offs: offset of the corresponding indexing node + * @len: length of the corresponding indexing node + * @zbranch: array of znode branches (@c->fanout elements) + * + * Note! The @lnum, @offs, and @len fields are not really needed - we have them + * only for internal consistency check. They could be removed to save some RAM. + */ +struct ubifs_znode { + struct ubifs_znode *parent; + struct ubifs_znode *cnext; + struct ubifs_znode *cparent; + int ciip; + unsigned long flags; + time64_t time; + int level; + int child_cnt; + int iip; + int alt; + int lnum; + int offs; + int len; + struct ubifs_zbranch zbranch[]; +}; + +/** + * struct ubifs_node_range - node length range description data structure. + * @len: fixed node length + * @min_len: minimum possible node length + * @max_len: maximum possible node length + * + * If @max_len is %0, the node has fixed length @len. + */ +struct ubifs_node_range { + union { + int len; + int min_len; + }; + int max_len; +}; + +/** + * struct ubifs_budget_req - budget requirements of an operation. + * + * @fast: non-zero if the budgeting should try to acquire budget quickly and + * should not try to call write-back + * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields + * have to be re-calculated + * @new_page: non-zero if the operation adds a new page + * @dirtied_page: non-zero if the operation makes a page dirty + * @new_dent: non-zero if the operation adds a new directory entry + * @mod_dent: non-zero if the operation removes or modifies an existing + * directory entry + * @new_ino: non-zero if the operation adds a new inode + * @new_ino_d: how much data newly created inode contains + * @dirtied_ino: how many inodes the operation makes dirty + * @dirtied_ino_d: how much data dirtied inode contains + * @idx_growth: how much the index will supposedly grow + * @data_growth: how much new data the operation will supposedly add + * @dd_growth: how much data that makes other data dirty the operation will + * supposedly add + * + * @idx_growth, @data_growth and @dd_growth are not used in budget request. The + * budgeting subsystem caches index and data growth values there to avoid + * re-calculating them when the budget is released. However, if @idx_growth is + * %-1, it is calculated by the release function using other fields. + * + * An inode may contain 4KiB of data at max., thus the widths of @new_ino_d + * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made + * dirty by the re-name operation. + * + * Note, UBIFS aligns node lengths to 8-bytes boundary, so the requester has to + * make sure the amount of inode data which contribute to @new_ino_d and + * @dirtied_ino_d fields are aligned. + */ +struct ubifs_budget_req { + unsigned int fast:1; + unsigned int recalculate:1; +#ifndef UBIFS_DEBUG + unsigned int new_page:1; + unsigned int dirtied_page:1; + unsigned int new_dent:1; + unsigned int mod_dent:1; + unsigned int new_ino:1; + unsigned int new_ino_d:13; + unsigned int dirtied_ino:4; + unsigned int dirtied_ino_d:15; +#else + /* Not bit-fields to check for overflows */ + unsigned int new_page; + unsigned int dirtied_page; + unsigned int new_dent; + unsigned int mod_dent; + unsigned int new_ino; + unsigned int new_ino_d; + unsigned int dirtied_ino; + unsigned int dirtied_ino_d; +#endif + int idx_growth; + int data_growth; + int dd_growth; +}; + +/** + * struct ubifs_orphan - stores the inode number of an orphan. + * @rb: rb-tree node of rb-tree of orphans sorted by inode number + * @list: list head of list of orphans in order added + * @new_list: list head of list of orphans added since the last commit + * @cnext: next orphan to commit + * @dnext: next orphan to delete + * @inum: inode number + * @new: %1 => added since the last commit, otherwise %0 + * @cmt: %1 => commit pending, otherwise %0 + * @del: %1 => delete pending, otherwise %0 + */ +struct ubifs_orphan { + struct rb_node rb; + struct list_head list; + struct list_head new_list; + struct ubifs_orphan *cnext; + struct ubifs_orphan *dnext; + ino_t inum; + unsigned new:1; + unsigned cmt:1; + unsigned del:1; +}; + +/** + * struct ubifs_budg_info - UBIFS budgeting information. + * @idx_growth: amount of bytes budgeted for index growth + * @data_growth: amount of bytes budgeted for cached data + * @dd_growth: amount of bytes budgeted for cached data that will make + * other data dirty + * @uncommitted_idx: amount of bytes were budgeted for growth of the index, but + * which still have to be taken into account because the index + * has not been committed so far + * @old_idx_sz: size of index on flash + * @min_idx_lebs: minimum number of LEBs required for the index + * @nospace: non-zero if the file-system does not have flash space (used as + * optimization) + * @nospace_rp: the same as @nospace, but additionally means that even reserved + * pool is full + * @page_budget: budget for a page (constant, never changed after mount) + * @inode_budget: budget for an inode (constant, never changed after mount) + * @dent_budget: budget for a directory entry (constant, never changed after + * mount) + */ +struct ubifs_budg_info { + long long idx_growth; + long long data_growth; + long long dd_growth; + long long uncommitted_idx; + unsigned long long old_idx_sz; + int min_idx_lebs; + unsigned int nospace:1; + unsigned int nospace_rp:1; + int page_budget; + int inode_budget; + int dent_budget; +}; + +/** + * struct ubifs_info - UBIFS file-system description data structure + * (per-superblock). + * + * @sup_node: The super block node as read from the device + * + * @highest_inum: highest used inode number + * @max_sqnum: current global sequence number + * @cmt_no: commit number of the last successfully completed commit, protected + * by @commit_sem + * @cnt_lock: protects @highest_inum and @max_sqnum counters + * @fmt_version: UBIFS on-flash format version + * @ro_compat_version: R/O compatibility version + * + * @debug_level: level of debug messages, 0 - none, 1 - error message, + * 2 - warning message, 3 - notice message, 4 - debug message + * @program_type: used to identify the type of current program + * @program_name: program name + * @dev_name: device name + * @dev_fd: opening handler for an UBI volume or an image file + * @libubi: opening handler for libubi + * + * @lhead_lnum: log head logical eraseblock number + * @lhead_offs: log head offset + * @ltail_lnum: log tail logical eraseblock number (offset is always 0) + * @log_mutex: protects the log, @lhead_lnum, @lhead_offs, @ltail_lnum, and + * @bud_bytes + * @min_log_bytes: minimum required number of bytes in the log + * @cmt_bud_bytes: used during commit to temporarily amount of bytes in + * committed buds + * + * @buds: tree of all buds indexed by bud LEB number + * @bud_bytes: how many bytes of flash is used by buds + * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud + * lists + * @jhead_cnt: count of journal heads + * @jheads: journal heads (head zero is base head) + * @max_bud_bytes: maximum number of bytes allowed in buds + * @bg_bud_bytes: number of bud bytes when background commit is initiated + * @old_buds: buds to be released after commit ends + * @max_bud_cnt: maximum number of buds + * + * @commit_sem: synchronizes committer with other processes + * @cmt_state: commit state + * @cs_lock: commit state lock + * + * @big_lpt: flag that LPT is too big to write whole during commit + * @space_fixup: flag indicating that free space in LEBs needs to be cleaned up + * @double_hash: flag indicating that we can do lookups by hash + * @encrypted: flag indicating that this file system contains encrypted files + * @no_chk_data_crc: do not check CRCs when reading data nodes (except during + * recovery) + * @authenticated: flag indigating the FS is mounted in authenticated mode + * @superblock_need_write: flag indicating that we need to write superblock node + * + * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and + * @calc_idx_sz + * @zroot: zbranch which points to the root index node and znode + * @cnext: next znode to commit + * @enext: next znode to commit to empty space + * @gap_lebs: array of LEBs used by the in-gaps commit method + * @cbuf: commit buffer + * @ileb_buf: buffer for commit in-the-gaps method + * @ileb_len: length of data in ileb_buf + * @ihead_lnum: LEB number of index head + * @ihead_offs: offset of index head + * @ilebs: pre-allocated index LEBs + * @ileb_cnt: number of pre-allocated index LEBs + * @ileb_nxt: next pre-allocated index LEBs + * @old_idx: tree of index nodes obsoleted since the last commit start + * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c + * + * @mst_node: master node + * @mst_offs: offset of valid master node + * + * @log_lebs: number of logical eraseblocks in the log + * @log_bytes: log size in bytes + * @log_last: last LEB of the log + * @lpt_lebs: number of LEBs used for lprops table + * @lpt_first: first LEB of the lprops table area + * @lpt_last: last LEB of the lprops table area + * @orph_lebs: number of LEBs used for the orphan area + * @orph_first: first LEB of the orphan area + * @orph_last: last LEB of the orphan area + * @main_lebs: count of LEBs in the main area + * @main_first: first LEB of the main area + * @main_bytes: main area size in bytes + * @default_compr: default compression type + * @favor_lzo: favor LZO compression method + * @favor_percent: lzo vs. zlib threshold used in case favor LZO + * + * @key_hash_type: type of the key hash + * @key_hash: direntry key hash function + * @key_fmt: key format + * @key_len: key length + * @fanout: fanout of the index tree (number of links per indexing node) + * + * @min_io_size: minimal input/output unit size + * @min_io_shift: number of bits in @min_io_size minus one + * @max_write_size: maximum amount of bytes the underlying flash can write at a + * time (MTD write buffer size) + * @max_write_shift: number of bits in @max_write_size minus one + * @leb_size: logical eraseblock size in bytes + * @half_leb_size: half LEB size + * @idx_leb_size: how many bytes of an LEB are effectively available when it is + * used to store indexing nodes (@leb_size - @max_idx_node_sz) + * @leb_cnt: count of logical eraseblocks + * @max_leb_cnt: maximum count of logical eraseblocks + * @ro_media: the underlying UBI volume is read-only + * @ro_mount: the file-system was mounted as read-only + * @ro_error: UBIFS switched to R/O mode because an error happened + * + * @dirty_pg_cnt: number of dirty pages (not used) + * @dirty_zn_cnt: number of dirty znodes + * @clean_zn_cnt: number of clean znodes + * + * @space_lock: protects @bi and @lst + * @lst: lprops statistics + * @bi: budgeting information + * @calc_idx_sz: temporary variable which is used to calculate new index size + * (contains accurate new index size at end of TNC commit start) + * + * @ref_node_alsz: size of the LEB reference node aligned to the min. flash + * I/O unit + * @mst_node_alsz: master node aligned size + * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary + * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary + * @max_inode_sz: maximum possible inode size in bytes + * @max_znode_sz: size of znode in bytes + * + * @leb_overhead: how many bytes are wasted in an LEB when it is filled with + * data nodes of maximum size - used in free space reporting + * @dead_wm: LEB dead space watermark + * @dark_wm: LEB dark space watermark + * + * @ranges: UBIFS node length ranges + * @di: UBI device information + * @vi: UBI volume information + * + * @orph_tree: rb-tree of orphan inode numbers + * @orph_list: list of orphan inode numbers in order added + * @orph_new: list of orphan inode numbers added since last commit + * @orph_cnext: next orphan to commit + * @orph_dnext: next orphan to delete + * @orphan_lock: lock for orph_tree and orph_new + * @orph_buf: buffer for orphan nodes + * @new_orphans: number of orphans since last commit + * @cmt_orphans: number of orphans being committed + * @tot_orphans: number of orphans in the rb_tree + * @max_orphans: maximum number of orphans allowed + * @ohead_lnum: orphan head LEB number + * @ohead_offs: orphan head offset + * @no_orphs: non-zero if there are no orphans + * + * @gc_lnum: LEB number used for garbage collection + * @sbuf: a buffer of LEB size used by GC and replay for scanning + * @idx_gc: list of index LEBs that have been garbage collected + * @idx_gc_cnt: number of elements on the idx_gc list + * @gc_seq: incremented for every non-index LEB garbage collected + * @gced_lnum: last non-index LEB that was garbage collected + * + * @space_bits: number of bits needed to record free or dirty space + * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT + * @lpt_offs_bits: number of bits needed to record an offset in the LPT + * @lpt_spc_bits: number of bits needed to space in the LPT + * @pcnt_bits: number of bits needed to record pnode or nnode number + * @lnum_bits: number of bits needed to record LEB number + * @nnode_sz: size of on-flash nnode + * @pnode_sz: size of on-flash pnode + * @ltab_sz: size of on-flash LPT lprops table + * @lsave_sz: size of on-flash LPT save table + * @pnode_cnt: number of pnodes + * @nnode_cnt: number of nnodes + * @lpt_hght: height of the LPT + * @pnodes_have: number of pnodes in memory + * + * @lp_mutex: protects lprops table and all the other lprops-related fields + * @lpt_lnum: LEB number of the root nnode of the LPT + * @lpt_offs: offset of the root nnode of the LPT + * @nhead_lnum: LEB number of LPT head + * @nhead_offs: offset of LPT head + * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab + * @dirty_nn_cnt: number of dirty nnodes + * @dirty_pn_cnt: number of dirty pnodes + * @check_lpt_free: flag that indicates LPT GC may be needed + * @lpt_sz: LPT size + * @lpt_nod_buf: buffer for an on-flash nnode or pnode + * @lpt_buf: buffer of LEB size used by LPT + * @nroot: address in memory of the root nnode of the LPT + * @lpt_cnext: next LPT node to commit + * @lpt_heap: array of heaps of categorized lprops + * @dirty_idx: a (reverse sorted) copy of the LPROPS_DIRTY_IDX heap as at + * previous commit start + * @uncat_list: list of un-categorized LEBs + * @empty_list: list of empty LEBs + * @freeable_list: list of freeable non-index LEBs (free + dirty == @leb_size) + * @frdi_idx_list: list of freeable index LEBs (free + dirty == @leb_size) + * @freeable_cnt: number of freeable LEBs in @freeable_list + * @in_a_category_cnt: count of lprops which are in a certain category, which + * basically meants that they were loaded from the flash + * + * @ltab_lnum: LEB number of LPT's own lprops table + * @ltab_offs: offset of LPT's own lprops table + * @lpt: lprops table + * @ltab: LPT's own lprops table + * @ltab_cmt: LPT's own lprops table (commit copy) + * @lsave_cnt: number of LEB numbers in LPT's save table + * @lsave_lnum: LEB number of LPT's save table + * @lsave_offs: offset of LPT's save table + * @lsave: LPT's save table + * @lscan_lnum: LEB number of last LPT scan + * + * @rp_size: reserved pool size + * + * @hash_algo_name: the name of the hashing algorithm to use + * @hash_algo: The hash algo number (from include/linux/hash_info.h) + * @auth_key_filename: authentication key file name + * @x509_filename: x509 certificate file name for authentication + * @hash_len: the length of the hash + * @root_idx_hash: The hash of the root index node + * @lpt_hash: The hash of the LPT + * @mst_hash: The hash of the master node + * @log_hash: the log hash from the commit start node up to the latest reference + * node. + * + * @need_recovery: %1 if the file-system needs recovery + * @replaying: %1 during journal replay + * @mounting: %1 while mounting + * @remounting_rw: %1 while re-mounting from R/O mode to R/W mode + * @replay_list: temporary list used during journal replay + * @replay_buds: list of buds to replay + * @cs_sqnum: sequence number of first node in the log (commit start node) + * @unclean_leb_list: LEBs to recover when re-mounting R/O mounted FS to R/W + * mode + * @rcvrd_mst_node: recovered master node to write when re-mounting R/O mounted + * FS to R/W mode + * @size_tree: inode size information for recovery + * + * @new_ihead_lnum: used by debugging to check @c->ihead_lnum + * @new_ihead_offs: used by debugging to check @c->ihead_offs + * + * @private: private information related to specific situation, eg. fsck. + * @assert_failed_cb: callback function to handle assertion failure + * @set_failure_reason_cb: record reasons while certain failure happens + * @get_failure_reason_cb: get failure reasons + * @clear_failure_reason_cb: callback function to clear the error which is + * caused by reading corrupted data or invalid lpt + * @test_and_clear_failure_reason_cb: callback function to check and clear the + * error which is caused by reading corrupted + * data or invalid lpt + * @set_lpt_invalid_cb: callback function to set the invalid lpt status + * @test_lpt_valid_cb: callback function to check whether lpt is corrupted or + * incorrect, should be called before updating lpt + * @can_ignore_failure_cb: callback function to decide whether the failure + * can be ignored + * @handle_failure_cb: callback function to decide whether the failure can be + * handled + */ +struct ubifs_info { + struct ubifs_sb_node *sup_node; + + ino_t highest_inum; + unsigned long long max_sqnum; + unsigned long long cmt_no; + spinlock_t cnt_lock; + int fmt_version; + int ro_compat_version; + + int debug_level; + int program_type; + const char *program_name; + char *dev_name; + int dev_fd; + libubi_t libubi; + + int lhead_lnum; + int lhead_offs; + int ltail_lnum; + struct mutex log_mutex; + int min_log_bytes; + long long cmt_bud_bytes; + + struct rb_root buds; + long long bud_bytes; + spinlock_t buds_lock; + int jhead_cnt; + struct ubifs_jhead *jheads; + long long max_bud_bytes; + long long bg_bud_bytes; + struct list_head old_buds; + int max_bud_cnt; + + struct rw_semaphore commit_sem; + int cmt_state; + spinlock_t cs_lock; + + unsigned int big_lpt:1; + unsigned int space_fixup:1; + unsigned int double_hash:1; + unsigned int encrypted:1; + unsigned int no_chk_data_crc:1; + unsigned int authenticated:1; + unsigned int superblock_need_write:1; + + struct mutex tnc_mutex; + struct ubifs_zbranch zroot; + struct ubifs_znode *cnext; + struct ubifs_znode *enext; + int *gap_lebs; + void *cbuf; + void *ileb_buf; + int ileb_len; + int ihead_lnum; + int ihead_offs; + int *ilebs; + int ileb_cnt; + int ileb_nxt; + struct rb_root old_idx; + int *bottom_up_buf; + + struct ubifs_mst_node *mst_node; + int mst_offs; + + int log_lebs; + long long log_bytes; + int log_last; + int lpt_lebs; + int lpt_first; + int lpt_last; + int orph_lebs; + int orph_first; + int orph_last; + int main_lebs; + int main_first; + long long main_bytes; + int default_compr; + int favor_lzo; + int favor_percent; + + uint8_t key_hash_type; + uint32_t (*key_hash)(const char *str, int len); + int key_fmt; + int key_len; + int fanout; + + int min_io_size; + int min_io_shift; + int max_write_size; + int max_write_shift; + int leb_size; + int half_leb_size; + int idx_leb_size; + int leb_cnt; + int max_leb_cnt; + unsigned int ro_media:1; + unsigned int ro_mount:1; + unsigned int ro_error:1; + + atomic_long_t dirty_pg_cnt; + atomic_long_t dirty_zn_cnt; + atomic_long_t clean_zn_cnt; + + spinlock_t space_lock; + struct ubifs_lp_stats lst; + struct ubifs_budg_info bi; + unsigned long long calc_idx_sz; + + int ref_node_alsz; + int mst_node_alsz; + int min_idx_node_sz; + int max_idx_node_sz; + long long max_inode_sz; + int max_znode_sz; + + int leb_overhead; + int dead_wm; + int dark_wm; + + struct ubifs_node_range ranges[UBIFS_NODE_TYPES_CNT]; + struct ubi_dev_info di; + struct ubi_vol_info vi; + + struct rb_root orph_tree; + struct list_head orph_list; + struct list_head orph_new; + struct ubifs_orphan *orph_cnext; + struct ubifs_orphan *orph_dnext; + spinlock_t orphan_lock; + void *orph_buf; + int new_orphans; + int cmt_orphans; + int tot_orphans; + int max_orphans; + int ohead_lnum; + int ohead_offs; + int no_orphs; + + int gc_lnum; + void *sbuf; + struct list_head idx_gc; + int idx_gc_cnt; + int gc_seq; + int gced_lnum; + + int space_bits; + int lpt_lnum_bits; + int lpt_offs_bits; + int lpt_spc_bits; + int pcnt_bits; + int lnum_bits; + int nnode_sz; + int pnode_sz; + int ltab_sz; + int lsave_sz; + int pnode_cnt; + int nnode_cnt; + int lpt_hght; + int pnodes_have; + + struct mutex lp_mutex; + int lpt_lnum; + int lpt_offs; + int nhead_lnum; + int nhead_offs; + int lpt_drty_flgs; + int dirty_nn_cnt; + int dirty_pn_cnt; + int check_lpt_free; + long long lpt_sz; + void *lpt_nod_buf; + void *lpt_buf; + struct ubifs_nnode *nroot; + struct ubifs_cnode *lpt_cnext; + struct ubifs_lpt_heap lpt_heap[LPROPS_HEAP_CNT]; + struct ubifs_lpt_heap dirty_idx; + struct list_head uncat_list; + struct list_head empty_list; + struct list_head freeable_list; + struct list_head frdi_idx_list; + int freeable_cnt; + int in_a_category_cnt; + + int ltab_lnum; + int ltab_offs; + struct ubifs_lprops *lpt; + struct ubifs_lpt_lprops *ltab; + struct ubifs_lpt_lprops *ltab_cmt; + int lsave_cnt; + int lsave_lnum; + int lsave_offs; + int *lsave; + int lscan_lnum; + + long long rp_size; + + char *hash_algo_name; + int hash_algo; + char *auth_key_filename; + char *auth_cert_filename; + int hash_len; + uint8_t root_idx_hash[UBIFS_MAX_HASH_LEN]; + uint8_t lpt_hash[UBIFS_MAX_HASH_LEN]; + uint8_t mst_hash[UBIFS_MAX_HASH_LEN]; + + struct shash_desc *log_hash; + + unsigned int need_recovery:1; + unsigned int replaying:1; + unsigned int mounting:1; + unsigned int remounting_rw:1; + struct list_head replay_list; + struct list_head replay_buds; + unsigned long long cs_sqnum; + struct list_head unclean_leb_list; + struct ubifs_mst_node *rcvrd_mst_node; + struct rb_root size_tree; + + int new_ihead_lnum; + int new_ihead_offs; + + void *private; + void (*assert_failed_cb)(const struct ubifs_info *c); + void (*set_failure_reason_cb)(const struct ubifs_info *c, + unsigned int reason); + unsigned int (*get_failure_reason_cb)(const struct ubifs_info *c); + void (*clear_failure_reason_cb)(const struct ubifs_info *c); + bool (*test_and_clear_failure_reason_cb)(const struct ubifs_info *c, + unsigned int reason); + void (*set_lpt_invalid_cb)(const struct ubifs_info *c, + unsigned int reason); + bool (*test_lpt_valid_cb)(const struct ubifs_info *c, int lnum, + int old_free, int old_dirty, + int free, int dirty); + bool (*can_ignore_failure_cb)(const struct ubifs_info *c, + unsigned int reason); + bool (*handle_failure_cb)(const struct ubifs_info *c, + unsigned int reason, void *priv); +}; + +extern atomic_long_t ubifs_clean_zn_cnt; + +/* auth.c */ +static inline int ubifs_authenticated(const struct ubifs_info *c) +{ + return c->authenticated; +} + +/** + * struct size_entry - inode size information for recovery. + * @rb: link in the RB-tree of sizes + * @inum: inode number + * @i_size: size on inode + * @d_size: maximum size based on data nodes + * @exists: indicates whether the inode exists + */ +struct size_entry { + struct rb_node rb; + ino_t inum; + loff_t i_size; + loff_t d_size; + int exists; +}; + +#ifdef WITH_CRYPTO +int ubifs_init_authentication(struct ubifs_info *c); +int ubifs_shash_init(const struct ubifs_info *c, struct shash_desc *desc); +int ubifs_shash_update(const struct ubifs_info *c, struct shash_desc *desc, + const void *buf, unsigned int len); +int ubifs_shash_final(const struct ubifs_info *c, struct shash_desc *desc, + u8 *out); +struct shash_desc *ubifs_hash_get_desc(const struct ubifs_info *c); +int __ubifs_node_calc_hash(const struct ubifs_info *c, const void *buf, + u8 *hash); +int ubifs_master_node_calc_hash(const struct ubifs_info *c, const void *node, + uint8_t *hash); +int ubifs_sign_superblock_node(struct ubifs_info *c, void *node); +void ubifs_bad_hash(const struct ubifs_info *c, const void *node, + const u8 *hash, int lnum, int offs); +void __ubifs_exit_authentication(struct ubifs_info *c); +#else +static inline int ubifs_init_authentication(__unused struct ubifs_info *c) +{ return 0; } +static inline int ubifs_shash_init(__unused const struct ubifs_info *c, + __unused struct shash_desc *desc) +{ return 0; } +static inline int ubifs_shash_update(__unused const struct ubifs_info *c, + __unused struct shash_desc *desc, + __unused const void *buf, + __unused unsigned int len) { return 0; } +static inline int ubifs_shash_final(__unused const struct ubifs_info *c, + __unused struct shash_desc *desc, + __unused u8 *out) { return 0; } +static inline struct shash_desc * +ubifs_hash_get_desc(__unused const struct ubifs_info *c) { return NULL; } +static inline int __ubifs_node_calc_hash(__unused const struct ubifs_info *c, + __unused const void *buf, + __unused u8 *hash) { return 0; } +static inline int +ubifs_master_node_calc_hash(__unused const struct ubifs_info *c, + __unused const void *node, __unused uint8_t *hash) +{ return 0; } +static inline int ubifs_sign_superblock_node(__unused struct ubifs_info *c, + __unused void *node) +{ return 0; } +static inline void ubifs_bad_hash(__unused const struct ubifs_info *c, + __unused const void *node, + __unused const u8 *hash, __unused int lnum, + __unused int offs) {} +static inline void __ubifs_exit_authentication(__unused struct ubifs_info *c) {} +#endif + +static inline int ubifs_prepare_auth_node(__unused struct ubifs_info *c, + __unused void *node, + __unused struct shash_desc *inhash) +{ + // To be implemented + return 0; +} + +static inline int +ubifs_node_calc_hash(const struct ubifs_info *c, const void *buf, u8 *hash) +{ + if (ubifs_authenticated(c)) + return __ubifs_node_calc_hash(c, buf, hash); + else + return 0; +} + +static inline int +ubifs_node_check_hash(__unused const struct ubifs_info *c, + __unused const void *buf, __unused const u8 *expected) +{ + // To be implemented + return 0; +} + +/** + * ubifs_check_hash - compare two hashes + * @c: UBIFS file-system description object + * @expected: first hash + * @got: second hash + * + * Compare two hashes @expected and @got. Returns 0 when they are equal, a + * negative error code otherwise. + */ +static inline int +ubifs_check_hash(__unused const struct ubifs_info *c, + __unused const u8 *expected, __unused const u8 *got) +{ + // To be implemented + return 0; +} + +/** + * ubifs_check_hmac - compare two HMACs + * @c: UBIFS file-system description object + * @expected: first HMAC + * @got: second HMAC + * + * Compare two hashes @expected and @got. Returns 0 when they are equal, a + * negative error code otherwise. + */ +static inline int +ubifs_check_hmac(__unused const struct ubifs_info *c, + __unused const u8 *expected, __unused const u8 *got) +{ + // To be implemented + return 0; +} + +/** + * ubifs_branch_hash - returns a pointer to the hash of a branch + * @c: UBIFS file-system description object + * @br: branch to get the hash from + * + * This returns a pointer to the hash of a branch. Since the key already is a + * dynamically sized object we cannot use a struct member here. + */ +static inline u8 * +ubifs_branch_hash(struct ubifs_info *c, struct ubifs_branch *br) +{ + return (void *)br + sizeof(*br) + c->key_len; +} + +/** + * ubifs_copy_hash - copy a hash + * @c: UBIFS file-system description object + * @from: source hash + * @to: destination hash + * + * With authentication this copies a hash, otherwise does nothing. + */ +static inline void +ubifs_copy_hash(const struct ubifs_info *c, const u8 *from, u8 *to) +{ + if (ubifs_authenticated(c)) + memcpy(to, from, c->hash_len); +} + +static inline int +ubifs_node_insert_hmac(__unused const struct ubifs_info *c, __unused void *buf, + __unused int len, __unused int ofs_hmac) +{ + // To be implemented + return 0; +} + +static inline int +ubifs_node_verify_hmac(__unused const struct ubifs_info *c, + __unused const void *buf, __unused int len, + __unused int ofs_hmac) +{ + // To be implemented + return 0; +} + +/** + * ubifs_auth_node_sz - returns the size of an authentication node + * @c: UBIFS file-system description object + * + * This function returns the size of an authentication node which can + * be 0 for unauthenticated filesystems or the real size of an auth node + * authentication is enabled. + */ +static inline int +ubifs_auth_node_sz(__unused const struct ubifs_info *c) +{ + // To be implemented + return 0; +} + +static inline bool +ubifs_hmac_zero(__unused struct ubifs_info *c, __unused const u8 *hmac) +{ + // To be implemented + return true; +} + +static inline int +ubifs_shash_copy_state(__unused const struct ubifs_info *c, + __unused struct shash_desc *src, + __unused struct shash_desc *target) +{ + // To be implemented + return 0; +} + +static inline void ubifs_exit_authentication(struct ubifs_info *c) +{ + if (ubifs_authenticated(c)) + __ubifs_exit_authentication(c); +} + +/* io.c */ +void ubifs_ro_mode(struct ubifs_info *c, int err); +int ubifs_leb_read(const struct ubifs_info *c, int lnum, void *buf, int offs, + int len, int even_ebadmsg); +int ubifs_leb_write(struct ubifs_info *c, int lnum, const void *buf, int offs, + int len); +int ubifs_leb_change(struct ubifs_info *c, int lnum, const void *buf, int len); +int ubifs_leb_unmap(struct ubifs_info *c, int lnum); +int ubifs_leb_map(struct ubifs_info *c, int lnum); +int ubifs_is_mapped(const struct ubifs_info *c, int lnum); +int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len); +int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs); +int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf); +int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len, + int lnum, int offs); +int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len, + int lnum, int offs); +int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum, + int offs); +int ubifs_write_node_hmac(struct ubifs_info *c, void *buf, int len, int lnum, + int offs, int hmac_offs); +int ubifs_check_node(const struct ubifs_info *c, const void *buf, int len, + int lnum, int offs, int quiet, int must_chk_crc); +void ubifs_init_node(struct ubifs_info *c, void *buf, int len, int pad); +void ubifs_crc_node(struct ubifs_info *c, void *buf, int len); +void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad); +int ubifs_prepare_node_hmac(struct ubifs_info *c, void *node, int len, + int hmac_offs, int pad); +void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last); +int ubifs_io_init(struct ubifs_info *c); +void ubifs_pad(const struct ubifs_info *c, void *buf, int pad); +int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf); + +/* scan.c */ +struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf, int quiet); +void ubifs_scan_destroy(struct ubifs_scan_leb *sleb); +int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum, + int offs, int quiet); +struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf); +void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + int lnum, int offs); +int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + void *buf, int offs); +void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs, + void *buf); + +/* Failure reasons which are checked by fsck. */ +enum { + FR_DATA_CORRUPTED = 1, /* Data is corrupted(master/log/orphan/main) */ + FR_TNC_CORRUPTED = 2, /* TNC is corrupted */ + FR_LPT_CORRUPTED = 4, /* LPT is corrupted */ + FR_LPT_INCORRECT = 8 /* Space statistics are wrong */ +}; +/* Partial failure reasons in common libs, which are handled by fsck. */ +enum { + FR_H_BUD_CORRUPTED = 0, /* Bud LEB is corrupted */ + FR_H_TNC_DATA_CORRUPTED, /* Data searched from TNC is corrupted */ + FR_H_ORPHAN_CORRUPTED, /* Orphan LEB is corrupted */ + FR_H_LTAB_INCORRECT, /* Lprops table is incorrect */ +}; +/* Callback functions for failure(which can be handled by fsck) happens. */ +static inline void set_failure_reason_callback(const struct ubifs_info *c, + unsigned int reason) +{ + if (c->set_failure_reason_cb) + c->set_failure_reason_cb(c, reason); +} +static inline unsigned int get_failure_reason_callback( + const struct ubifs_info *c) +{ + if (c->get_failure_reason_cb) + return c->get_failure_reason_cb(c); + + return 0; +} +static inline void clear_failure_reason_callback(const struct ubifs_info *c) +{ + if (c->clear_failure_reason_cb) + c->clear_failure_reason_cb(c); +} +static inline bool test_and_clear_failure_reason_callback( + const struct ubifs_info *c, + unsigned int reason) +{ + if (c->test_and_clear_failure_reason_cb) + return c->test_and_clear_failure_reason_cb(c, reason); + + return false; +} +static inline void set_lpt_invalid_callback(const struct ubifs_info *c, + unsigned int reason) +{ + if (c->set_lpt_invalid_cb) + c->set_lpt_invalid_cb(c, reason); +} +static inline bool test_lpt_valid_callback(const struct ubifs_info *c, int lnum, + int old_free, int old_dirty, + int free, int dirty) +{ + if (c->test_lpt_valid_cb) + return c->test_lpt_valid_cb(c, lnum, + old_free, old_dirty, free, dirty); + + return false; +} +static inline bool can_ignore_failure_callback(const struct ubifs_info *c, + unsigned int reason) +{ + if (c->can_ignore_failure_cb) + return c->can_ignore_failure_cb(c, reason); + + return false; +} +static inline bool handle_failure_callback(const struct ubifs_info *c, + unsigned int reason, void *priv) +{ + if (c->handle_failure_cb) + return c->handle_failure_cb(c, reason, priv); + + return false; +} + +/* log.c */ +void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud); +void ubifs_create_buds_lists(struct ubifs_info *c); +int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs); +struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum); +struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum); +int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum); +int ubifs_log_end_commit(struct ubifs_info *c, int new_ltail_lnum); +int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum); +int ubifs_consolidate_log(struct ubifs_info *c); + +/* journal.c */ +int ubifs_get_dent_type(int mode); +int ubifs_jnl_update_file(struct ubifs_info *c, + const struct ubifs_inode *dir_ui, + const struct fscrypt_name *nm, + const struct ubifs_inode *ui); + +/* budget.c */ +int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req); +void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req); +long long ubifs_get_free_space_nolock(struct ubifs_info *c); +int ubifs_calc_min_idx_lebs(struct ubifs_info *c); +long long ubifs_reported_space(const struct ubifs_info *c, long long free); +long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs); + +/* find.c */ +int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *offs, + int squeeze); +int ubifs_find_free_leb_for_idx(struct ubifs_info *c); +int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp, + int min_space, int pick_free); +int ubifs_find_dirty_idx_leb(struct ubifs_info *c); +int ubifs_save_dirty_idx_lnums(struct ubifs_info *c); + +/* tnc.c */ +int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n); +int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, + void *node, const struct fscrypt_name *nm); +int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key, + void *node, int *lnum, int *offs); +int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum, + int offs, int len, const u8 *hash); +int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key, + int old_lnum, int old_offs, int lnum, int offs, int len); +int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key, + int lnum, int offs, int len, const u8 *hash, + const struct fscrypt_name *nm); +int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key); +int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key, + const struct fscrypt_name *nm); +int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key, + union ubifs_key *to_key); +int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum); +int ubifs_tnc_remove_node(struct ubifs_info *c, const union ubifs_key *key, + int lnum, int offs); +struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c, + union ubifs_key *key, + const struct fscrypt_name *nm); +void ubifs_tnc_close(struct ubifs_info *c); +int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs, int is_idx); +int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs); +/* Shared by tnc.c for tnc_commit.c */ +void destroy_old_idx(struct ubifs_info *c); +int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs); +int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode); + +/* tnc_misc.c */ +int ubifs_search_zbranch(const struct ubifs_info *c, + const struct ubifs_znode *znode, + const union ubifs_key *key, int *n); +struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode); +struct ubifs_znode *ubifs_tnc_postorder_next(const struct ubifs_info *c, + struct ubifs_znode *znode); +long ubifs_destroy_tnc_subtree(const struct ubifs_info *c, + struct ubifs_znode *zr); +void ubifs_destroy_tnc_tree(struct ubifs_info *c); +struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c, + struct ubifs_zbranch *zbr, + struct ubifs_znode *parent, int iip); +int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node); + +/* tnc_commit.c */ +int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot); +int ubifs_tnc_end_commit(struct ubifs_info *c); + +/* commit.c */ +void ubifs_commit_required(struct ubifs_info *c); +void ubifs_request_bg_commit(struct ubifs_info *c); +int ubifs_run_commit(struct ubifs_info *c); +void ubifs_recovery_commit(struct ubifs_info *c); +int ubifs_gc_should_commit(struct ubifs_info *c); +void ubifs_wait_for_commit(struct ubifs_info *c); + +/* master.c */ +int ubifs_compare_master_node(struct ubifs_info *c, void *m1, void *m2); +int ubifs_read_master(struct ubifs_info *c); +int ubifs_write_master(struct ubifs_info *c); + +/* sb.c */ +int ubifs_read_superblock(struct ubifs_info *c); +int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup); +int ubifs_fixup_free_space(struct ubifs_info *c); + +/* replay.c */ +int ubifs_validate_entry(struct ubifs_info *c, + const struct ubifs_dent_node *dent); +int take_ihead(struct ubifs_info *c); +int ubifs_replay_journal(struct ubifs_info *c); + +/* gc.c */ +int ubifs_garbage_collect(struct ubifs_info *c, int anyway); +int ubifs_gc_start_commit(struct ubifs_info *c); +int ubifs_gc_end_commit(struct ubifs_info *c); +void ubifs_destroy_idx_gc(struct ubifs_info *c); +int ubifs_get_idx_gc_leb(struct ubifs_info *c); +int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp); + +/* orphan.c */ +int ubifs_orphan_start_commit(struct ubifs_info *c); +int ubifs_orphan_end_commit(struct ubifs_info *c); +int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only); +int ubifs_clear_orphans(struct ubifs_info *c); + +/* lpt.c */ +int ubifs_calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs, int *big_lpt); +int ubifs_calc_lpt_geom(struct ubifs_info *c); +int ubifs_create_lpt(struct ubifs_info *c, struct ubifs_lprops *lps, int lp_cnt, + u8 *hash, bool free_ltab); +int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr); +struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum); +struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum); +int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum, + ubifs_lpt_scan_callback scan_cb, void *data); + +/* Shared by lpt.c for lpt_commit.c */ +void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave); +void ubifs_pack_ltab(struct ubifs_info *c, void *buf, + struct ubifs_lpt_lprops *ltab); +void ubifs_pack_pnode(struct ubifs_info *c, void *buf, + struct ubifs_pnode *pnode); +void ubifs_pack_nnode(struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode); +struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip); +struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip); +struct ubifs_pnode *ubifs_pnode_lookup(struct ubifs_info *c, int i); +int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip); +void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty); +void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode); +uint32_t ubifs_unpack_bits(const struct ubifs_info *c, uint8_t **addr, int *pos, int nrbits); +int ubifs_calc_nnode_num(int row, int col); +struct ubifs_nnode *ubifs_first_nnode(struct ubifs_info *c, int *hght); +/* Needed only in debugging code in lpt_commit.c */ +int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode); +int ubifs_lpt_calc_hash(struct ubifs_info *c, u8 *hash); + +/* lpt_commit.c */ +struct ubifs_pnode *ubifs_find_next_pnode(struct ubifs_info *c, + struct ubifs_pnode *pnode); +void ubifs_make_nnode_dirty(struct ubifs_info *c, struct ubifs_nnode *nnode); +void ubifs_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode); +int ubifs_lpt_start_commit(struct ubifs_info *c); +int ubifs_lpt_end_commit(struct ubifs_info *c); +int ubifs_lpt_post_commit(struct ubifs_info *c); +void ubifs_free_lpt_nodes(struct ubifs_info *c); +void ubifs_lpt_free(struct ubifs_info *c, int wr_only); +int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum); + +/* lprops.c */ +const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c, + const struct ubifs_lprops *lp, + int free, int dirty, int flags, + int idx_gc_cnt); +void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst); +void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops, + int cat); +void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops, + struct ubifs_lprops *new_lprops); +void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops); +int ubifs_categorize_lprops(const struct ubifs_info *c, + const struct ubifs_lprops *lprops); +int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean, int idx_gc_cnt); +int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean); +int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp); +const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c); +const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c); +const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c); +const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c); +int ubifs_calc_dark(const struct ubifs_info *c, int spc); + +/* dir.c */ +struct ubifs_inode *ubifs_lookup_by_inum(struct ubifs_info *c, ino_t inum); +struct ubifs_inode *ubifs_lookup(struct ubifs_info *c, + struct ubifs_inode *dir_ui, + const struct fscrypt_name *nm); +int ubifs_mkdir(struct ubifs_info *c, struct ubifs_inode *dir_ui, + const struct fscrypt_name *nm, unsigned int mode); +int ubifs_link_recovery(struct ubifs_info *c, struct ubifs_inode *dir_ui, + struct ubifs_inode *ui, const struct fscrypt_name *nm); +int ubifs_create_root(struct ubifs_info *c); + +/* super.c */ +int open_ubi(struct ubifs_info *c, const char *node); +void close_ubi(struct ubifs_info *c); +int open_target(struct ubifs_info *c); +int close_target(struct ubifs_info *c); +int ubifs_open_volume(struct ubifs_info *c, const char *volume_name); +int ubifs_close_volume(struct ubifs_info *c); +int check_volume_empty(struct ubifs_info *c); +void init_ubifs_info(struct ubifs_info *c, int program_type); +int init_constants_early(struct ubifs_info *c); +int init_constants_sb(struct ubifs_info *c); +void init_constants_master(struct ubifs_info *c); +int take_gc_lnum(struct ubifs_info *c); +int alloc_wbufs(struct ubifs_info *c); +void free_wbufs(struct ubifs_info *c); +void free_orphans(struct ubifs_info *c); +void free_buds(struct ubifs_info *c, bool delete_from_list); +void destroy_journal(struct ubifs_info *c); + +/* recovery.c */ +int ubifs_recover_master_node(struct ubifs_info *c); +struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf, int jhead); +struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf); +int ubifs_recover_inl_heads(struct ubifs_info *c, void *sbuf); +int ubifs_rcvry_gc_commit(struct ubifs_info *c); +int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key, + int deletion, loff_t new_size); +int ubifs_recover_size(struct ubifs_info *c, bool in_place); +void ubifs_destroy_size_tree(struct ubifs_info *c); + +/* Normal UBIFS messages */ +enum { ERR_LEVEL = 1, WARN_LEVEL, INFO_LEVEL, DEBUG_LEVEL }; +#define ubifs_msg(c, fmt, ...) do { \ + if (c->debug_level >= INFO_LEVEL) \ + printf("<INFO> %s[%d] (%s): %s: " fmt "\n", \ + c->program_name, getpid(), \ + c->dev_name, __FUNCTION__, ##__VA_ARGS__); \ +} while (0) +#define ubifs_warn(c, fmt, ...) do { \ + if (c->debug_level >= WARN_LEVEL) \ + printf("<WARN> %s[%d] (%s): %s: " fmt "\n", \ + c->program_name, getpid(), \ + c->dev_name, __FUNCTION__, ##__VA_ARGS__); \ +} while (0) +#define ubifs_err(c, fmt, ...) do { \ + if (c->debug_level >= ERR_LEVEL) \ + printf("<ERROR> %s[%d] (%s): %s: " fmt "\n", \ + c->program_name, getpid(), \ + c->dev_name, __FUNCTION__, ##__VA_ARGS__); \ +} while (0) + +#endif /* !__UBIFS_H__ */ |