From df5d5489aed7ae9de007776e19350bd5aebbfea2 Mon Sep 17 00:00:00 2001 From: Zhihao Cheng Date: Mon, 11 Nov 2024 17:08:12 +0800 Subject: ubifs-utils: libubifs: Support some file operations Add some file operations, such as ubifs_lookup, ubifs_mkdir, etc., this is a preparation for recovering disconnected files or root dir in fsck. File writing operations are based on the journal subsystem, generated dirty data depends on a new commit in subsequent steps to update disk content. Signed-off-by: Zhihao Cheng Signed-off-by: David Oberhollenzer --- ubifs-utils/libubifs/dir.c | 359 +++++++++++++++++++++++++++++++++++++++++ ubifs-utils/libubifs/journal.c | 194 ++++++++++++++++++++++ ubifs-utils/libubifs/misc.h | 9 ++ ubifs-utils/libubifs/ubifs.h | 45 ++++++ 4 files changed, 607 insertions(+) (limited to 'ubifs-utils/libubifs') diff --git a/ubifs-utils/libubifs/dir.c b/ubifs-utils/libubifs/dir.c index 9d5f644..89f77eb 100644 --- a/ubifs-utils/libubifs/dir.c +++ b/ubifs-utils/libubifs/dir.c @@ -28,4 +28,363 @@ * write it, but just marks it as dirty. */ +#include + +#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/journal.c b/ubifs-utils/libubifs/journal.c index d3fdb76..e78ea14 100644 --- a/ubifs-utils/libubifs/journal.c +++ b/ubifs-utils/libubifs/journal.c @@ -47,9 +47,11 @@ */ #include "bitops.h" +#include "kmem.h" #include "ubifs.h" #include "defs.h" #include "debug.h" +#include "key.h" #include "misc.h" /** @@ -437,3 +439,195 @@ static void set_dent_cookie(struct ubifs_info *c, struct ubifs_dent_node *dent) 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/misc.h b/ubifs-utils/libubifs/misc.h index 4b71806..1b4404f 100644 --- a/ubifs-utils/libubifs/misc.h +++ b/ubifs-utils/libubifs/misc.h @@ -69,6 +69,15 @@ ubifs_tnc_find_child(struct ubifs_znode *znode, int start) 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 diff --git a/ubifs-utils/libubifs/ubifs.h b/ubifs-utils/libubifs/ubifs.h index a4b05a6..0908a22 100644 --- a/ubifs-utils/libubifs/ubifs.h +++ b/ubifs-utils/libubifs/ubifs.h @@ -261,8 +261,37 @@ struct ubifs_gced_idx_leb { 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 @@ -275,6 +304,7 @@ struct ubifs_gced_idx_leb { * @data: inode's data */ struct ubifs_inode { + struct inode vfs_inode; unsigned long long creat_sqnum; unsigned int xattr_size; unsigned int xattr_cnt; @@ -1640,6 +1670,10 @@ 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); @@ -1823,6 +1857,17 @@ 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); -- cgit v1.2.3