diff options
| -rw-r--r-- | ubifs-utils/libubifs/commit.c | 370 |
1 files changed, 10 insertions, 360 deletions
diff --git a/ubifs-utils/libubifs/commit.c b/ubifs-utils/libubifs/commit.c index 5b3a840..f3b6113 100644 --- a/ubifs-utils/libubifs/commit.c +++ b/ubifs-utils/libubifs/commit.c @@ -31,10 +31,13 @@ * cache. */ -#include <linux/freezer.h> -#include <linux/kthread.h> -#include <linux/slab.h> +#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. @@ -216,7 +219,6 @@ static int do_commit(struct ubifs_info *c) out_cancel: spin_lock(&c->cs_lock); c->cmt_state = COMMIT_RESTING; - wake_up(&c->cmt_wq); dbg_cmt("commit end"); spin_unlock(&c->cs_lock); return 0; @@ -227,107 +229,12 @@ out: ubifs_err(c, "commit failed, error %d", err); spin_lock(&c->cs_lock); c->cmt_state = COMMIT_BROKEN; - wake_up(&c->cmt_wq); spin_unlock(&c->cs_lock); ubifs_ro_mode(c, err); return err; } /** - * run_bg_commit - run background commit if it is needed. - * @c: UBIFS file-system description object - * - * This function runs background commit if it is needed. Returns zero in case - * of success and a negative error code in case of failure. - */ -static int run_bg_commit(struct ubifs_info *c) -{ - spin_lock(&c->cs_lock); - /* - * Run background commit only if background commit was requested or if - * commit is required. - */ - if (c->cmt_state != COMMIT_BACKGROUND && - c->cmt_state != COMMIT_REQUIRED) - goto out; - spin_unlock(&c->cs_lock); - - down_write(&c->commit_sem); - spin_lock(&c->cs_lock); - if (c->cmt_state == COMMIT_REQUIRED) - c->cmt_state = COMMIT_RUNNING_REQUIRED; - else if (c->cmt_state == COMMIT_BACKGROUND) - c->cmt_state = COMMIT_RUNNING_BACKGROUND; - else - goto out_cmt_unlock; - spin_unlock(&c->cs_lock); - - return do_commit(c); - -out_cmt_unlock: - up_write(&c->commit_sem); -out: - spin_unlock(&c->cs_lock); - return 0; -} - -/** - * ubifs_bg_thread - UBIFS background thread function. - * @info: points to the file-system description object - * - * This function implements various file-system background activities: - * o when a write-buffer timer expires it synchronizes the appropriate - * write-buffer; - * o when the journal is about to be full, it starts in-advance commit. - * - * Note, other stuff like background garbage collection may be added here in - * future. - */ -int ubifs_bg_thread(void *info) -{ - int err; - struct ubifs_info *c = info; - - ubifs_msg(c, "background thread \"%s\" started, PID %d", - c->bgt_name, current->pid); - set_freezable(); - - while (1) { - if (kthread_should_stop()) - break; - - if (try_to_freeze()) - continue; - - set_current_state(TASK_INTERRUPTIBLE); - /* Check if there is something to do */ - if (!c->need_bgt) { - /* - * Nothing prevents us from going sleep now and - * be never woken up and block the task which - * could wait in 'kthread_stop()' forever. - */ - if (kthread_should_stop()) - break; - schedule(); - continue; - } else - __set_current_state(TASK_RUNNING); - - c->need_bgt = 0; - err = ubifs_bg_wbufs_sync(c); - if (err) - ubifs_ro_mode(c, err); - - run_bg_commit(c); - cond_resched(); - } - - ubifs_msg(c, "background thread \"%s\" stops", c->bgt_name); - return 0; -} - -/** * ubifs_commit_required - set commit state to "required". * @c: UBIFS file-system description object * @@ -364,17 +271,8 @@ void ubifs_commit_required(struct ubifs_info *c) * 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(struct ubifs_info *c) +void ubifs_request_bg_commit(__unused struct ubifs_info *c) { - spin_lock(&c->cs_lock); - if (c->cmt_state == COMMIT_RESTING) { - dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state), - dbg_cstate(COMMIT_BACKGROUND)); - c->cmt_state = COMMIT_BACKGROUND; - spin_unlock(&c->cs_lock); - ubifs_wake_up_bgt(c); - } else - spin_unlock(&c->cs_lock); } /** @@ -385,18 +283,11 @@ void ubifs_request_bg_commit(struct ubifs_info *c) */ static int wait_for_commit(struct ubifs_info *c) { - dbg_cmt("pid %d goes sleep", current->pid); - /* - * The following sleeps if the condition is false, and will be woken - * when the commit ends. It is possible, although very unlikely, that we - * will wake up and see the subsequent commit running, rather than the - * one we were waiting for, and go back to sleep. However, we will be - * woken again, so there is no danger of sleeping forever. + * All commit operations are executed in synchronization context, + * so it is impossible that more than one threads doing commit. */ - wait_event(c->cmt_wq, c->cmt_state != COMMIT_RUNNING_BACKGROUND && - c->cmt_state != COMMIT_RUNNING_REQUIRED); - dbg_cmt("commit finished, pid %d woke up", current->pid); + ubifs_assert(c, 0); return 0; } @@ -490,244 +381,3 @@ int ubifs_gc_should_commit(struct ubifs_info *c) spin_unlock(&c->cs_lock); return ret; } - -/* - * Everything below is related to debugging. - */ - -/** - * struct idx_node - hold index nodes during index tree traversal. - * @list: list - * @iip: index in parent (slot number of this indexing node in the parent - * indexing node) - * @upper_key: all keys in this indexing node have to be less or equivalent to - * this key - * @idx: index node (8-byte aligned because all node structures must be 8-byte - * aligned) - */ -struct idx_node { - struct list_head list; - int iip; - union ubifs_key upper_key; - struct ubifs_idx_node idx __aligned(8); -}; - -/** - * dbg_old_index_check_init - get information for the next old index check. - * @c: UBIFS file-system description object - * @zroot: root of the index - * - * This function records information about the index that will be needed for the - * next old index check i.e. 'dbg_check_old_index()'. - * - * This function returns %0 on success and a negative error code on failure. - */ -int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot) -{ - struct ubifs_idx_node *idx; - int lnum, offs, len, err = 0; - struct ubifs_debug_info *d = c->dbg; - - d->old_zroot = *zroot; - lnum = d->old_zroot.lnum; - offs = d->old_zroot.offs; - len = d->old_zroot.len; - - 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) - goto out; - - d->old_zroot_level = le16_to_cpu(idx->level); - d->old_zroot_sqnum = le64_to_cpu(idx->ch.sqnum); -out: - kfree(idx); - return err; -} - -/** - * dbg_check_old_index - check the old copy of the index. - * @c: UBIFS file-system description object - * @zroot: root of the new index - * - * In order to be able to recover from an unclean unmount, a complete copy of - * the index must exist on flash. This is the "old" index. The commit process - * must write the "new" index to flash without overwriting or destroying any - * part of the old index. This function is run at commit end in order to check - * that the old index does indeed exist completely intact. - * - * This function returns %0 on success and a negative error code on failure. - */ -int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot) -{ - int lnum, offs, len, err = 0, last_level, child_cnt; - int first = 1, iip; - struct ubifs_debug_info *d = c->dbg; - union ubifs_key lower_key, upper_key, l_key, u_key; - unsigned long long last_sqnum; - struct ubifs_idx_node *idx; - struct list_head list; - struct idx_node *i; - size_t sz; - - if (!dbg_is_chk_index(c)) - return 0; - - INIT_LIST_HEAD(&list); - - sz = sizeof(struct idx_node) + ubifs_idx_node_sz(c, c->fanout) - - UBIFS_IDX_NODE_SZ; - - /* Start at the old zroot */ - lnum = d->old_zroot.lnum; - offs = d->old_zroot.offs; - len = d->old_zroot.len; - iip = 0; - - /* - * Traverse the index tree preorder depth-first i.e. do a node and then - * its subtrees from left to right. - */ - while (1) { - struct ubifs_branch *br; - - /* Get the next index node */ - i = kmalloc(sz, GFP_NOFS); - if (!i) { - err = -ENOMEM; - goto out_free; - } - i->iip = iip; - /* Keep the index nodes on our path in a linked list */ - list_add_tail(&i->list, &list); - /* Read the index node */ - idx = &i->idx; - err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs); - if (err) - goto out_free; - /* Validate index node */ - child_cnt = le16_to_cpu(idx->child_cnt); - if (child_cnt < 1 || child_cnt > c->fanout) { - err = 1; - goto out_dump; - } - if (first) { - first = 0; - /* Check root level and sqnum */ - if (le16_to_cpu(idx->level) != d->old_zroot_level) { - err = 2; - goto out_dump; - } - if (le64_to_cpu(idx->ch.sqnum) != d->old_zroot_sqnum) { - err = 3; - goto out_dump; - } - /* Set last values as though root had a parent */ - last_level = le16_to_cpu(idx->level) + 1; - last_sqnum = le64_to_cpu(idx->ch.sqnum) + 1; - key_read(c, ubifs_idx_key(c, idx), &lower_key); - highest_ino_key(c, &upper_key, INUM_WATERMARK); - } - key_copy(c, &upper_key, &i->upper_key); - if (le16_to_cpu(idx->level) != last_level - 1) { - err = 3; - goto out_dump; - } - /* - * The index is always written bottom up hence a child's sqnum - * is always less than the parents. - */ - if (le64_to_cpu(idx->ch.sqnum) >= last_sqnum) { - err = 4; - goto out_dump; - } - /* Check key range */ - key_read(c, ubifs_idx_key(c, idx), &l_key); - br = ubifs_idx_branch(c, idx, child_cnt - 1); - key_read(c, &br->key, &u_key); - if (keys_cmp(c, &lower_key, &l_key) > 0) { - err = 5; - goto out_dump; - } - if (keys_cmp(c, &upper_key, &u_key) < 0) { - err = 6; - goto out_dump; - } - if (keys_cmp(c, &upper_key, &u_key) == 0) - if (!is_hash_key(c, &u_key)) { - err = 7; - goto out_dump; - } - /* Go to next index node */ - if (le16_to_cpu(idx->level) == 0) { - /* At the bottom, so go up until can go right */ - while (1) { - /* Drop the bottom of the list */ - list_del(&i->list); - kfree(i); - /* No more list means we are done */ - if (list_empty(&list)) - goto out; - /* Look at the new bottom */ - i = list_entry(list.prev, struct idx_node, - list); - idx = &i->idx; - /* Can we go right */ - if (iip + 1 < le16_to_cpu(idx->child_cnt)) { - iip = iip + 1; - break; - } else - /* Nope, so go up again */ - iip = i->iip; - } - } else - /* Go down left */ - iip = 0; - /* - * We have the parent in 'idx' and now we set up for reading the - * child pointed to by slot 'iip'. - */ - last_level = le16_to_cpu(idx->level); - last_sqnum = le64_to_cpu(idx->ch.sqnum); - br = ubifs_idx_branch(c, idx, iip); - lnum = le32_to_cpu(br->lnum); - offs = le32_to_cpu(br->offs); - len = le32_to_cpu(br->len); - key_read(c, &br->key, &lower_key); - if (iip + 1 < le16_to_cpu(idx->child_cnt)) { - br = ubifs_idx_branch(c, idx, iip + 1); - key_read(c, &br->key, &upper_key); - } else - key_copy(c, &i->upper_key, &upper_key); - } -out: - err = dbg_old_index_check_init(c, zroot); - if (err) - goto out_free; - - return 0; - -out_dump: - ubifs_err(c, "dumping index node (iip=%d)", i->iip); - ubifs_dump_node(c, idx, ubifs_idx_node_sz(c, c->fanout)); - list_del(&i->list); - kfree(i); - if (!list_empty(&list)) { - i = list_entry(list.prev, struct idx_node, list); - ubifs_err(c, "dumping parent index node"); - ubifs_dump_node(c, &i->idx, ubifs_idx_node_sz(c, c->fanout)); - } -out_free: - while (!list_empty(&list)) { - i = list_entry(list.next, struct idx_node, list); - list_del(&i->list); - kfree(i); - } - ubifs_err(c, "failed, error %d", err); - if (err > 0) - err = -EINVAL; - return err; -} |