diff options
Diffstat (limited to 'fs/ubifs/journal.c')
| -rw-r--r-- | fs/ubifs/journal.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c index 6b27ddd2c484..8e07f132e024 100644 --- a/fs/ubifs/journal.c +++ b/fs/ubifs/journal.c @@ -908,6 +908,147 @@ int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode) } /** + * ubifs_jnl_xrename - cross rename two directory entries. + * @c: UBIFS file-system description object + * @fst_dir: parent inode of 1st directory entry to exchange + * @fst_dentry: 1st directory entry to exchange + * @snd_dir: parent inode of 2nd directory entry to exchange + * @snd_dentry: 2nd directory entry to exchange + * @sync: non-zero if the write-buffer has to be synchronized + * + * This function implements the cross rename operation which may involve + * writing 2 inodes and 2 directory entries. It marks the written inodes as clean + * and returns zero on success. In case of failure, a negative error code is + * returned. + */ +int ubifs_jnl_xrename(struct ubifs_info *c, const struct inode *fst_dir, + const struct dentry *fst_dentry, + const struct inode *snd_dir, + const struct dentry *snd_dentry, int sync) +{ + union ubifs_key key; + struct ubifs_dent_node *dent1, *dent2; + int err, dlen1, dlen2, lnum, offs, len, plen = UBIFS_INO_NODE_SZ; + int aligned_dlen1, aligned_dlen2; + int twoparents = (fst_dir != snd_dir); + const struct inode *fst_inode = d_inode(fst_dentry); + const struct inode *snd_inode = d_inode(snd_dentry); + void *p; + + dbg_jnl("dent '%pd' in dir ino %lu between dent '%pd' in dir ino %lu", + fst_dentry, fst_dir->i_ino, snd_dentry, snd_dir->i_ino); + + ubifs_assert(ubifs_inode(fst_dir)->data_len == 0); + ubifs_assert(ubifs_inode(snd_dir)->data_len == 0); + ubifs_assert(mutex_is_locked(&ubifs_inode(fst_dir)->ui_mutex)); + ubifs_assert(mutex_is_locked(&ubifs_inode(snd_dir)->ui_mutex)); + + dlen1 = UBIFS_DENT_NODE_SZ + snd_dentry->d_name.len + 1; + dlen2 = UBIFS_DENT_NODE_SZ + fst_dentry->d_name.len + 1; + aligned_dlen1 = ALIGN(dlen1, 8); + aligned_dlen2 = ALIGN(dlen2, 8); + + len = aligned_dlen1 + aligned_dlen2 + ALIGN(plen, 8); + if (twoparents) + len += plen; + + dent1 = kmalloc(len, GFP_NOFS); + if (!dent1) + return -ENOMEM; + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, BASEHD, len); + if (err) + goto out_free; + + /* Make new dent for 1st entry */ + dent1->ch.node_type = UBIFS_DENT_NODE; + dent_key_init_flash(c, &dent1->key, snd_dir->i_ino, &snd_dentry->d_name); + dent1->inum = cpu_to_le64(fst_inode->i_ino); + dent1->type = get_dent_type(fst_inode->i_mode); + dent1->nlen = cpu_to_le16(snd_dentry->d_name.len); + memcpy(dent1->name, snd_dentry->d_name.name, snd_dentry->d_name.len); + dent1->name[snd_dentry->d_name.len] = '\0'; + zero_dent_node_unused(dent1); + ubifs_prep_grp_node(c, dent1, dlen1, 0); + + /* Make new dent for 2nd entry */ + dent2 = (void *)dent1 + aligned_dlen1; + dent2->ch.node_type = UBIFS_DENT_NODE; + dent_key_init_flash(c, &dent2->key, fst_dir->i_ino, &fst_dentry->d_name); + dent2->inum = cpu_to_le64(snd_inode->i_ino); + dent2->type = get_dent_type(snd_inode->i_mode); + dent2->nlen = cpu_to_le16(fst_dentry->d_name.len); + memcpy(dent2->name, fst_dentry->d_name.name, fst_dentry->d_name.len); + dent2->name[fst_dentry->d_name.len] = '\0'; + zero_dent_node_unused(dent2); + ubifs_prep_grp_node(c, dent2, dlen2, 0); + + p = (void *)dent2 + aligned_dlen2; + if (!twoparents) + pack_inode(c, p, fst_dir, 1); + else { + pack_inode(c, p, fst_dir, 0); + p += ALIGN(plen, 8); + pack_inode(c, p, snd_dir, 1); + } + + err = write_head(c, BASEHD, dent1, len, &lnum, &offs, sync); + if (err) + goto out_release; + if (!sync) { + struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf; + + ubifs_wbuf_add_ino_nolock(wbuf, fst_dir->i_ino); + ubifs_wbuf_add_ino_nolock(wbuf, snd_dir->i_ino); + } + release_head(c, BASEHD); + + dent_key_init(c, &key, snd_dir->i_ino, &snd_dentry->d_name); + err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &snd_dentry->d_name); + if (err) + goto out_ro; + + offs += aligned_dlen1; + dent_key_init(c, &key, fst_dir->i_ino, &fst_dentry->d_name); + err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen2, &fst_dentry->d_name); + if (err) + goto out_ro; + + offs += aligned_dlen2; + + ino_key_init(c, &key, fst_dir->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs, plen); + if (err) + goto out_ro; + + if (twoparents) { + offs += ALIGN(plen, 8); + ino_key_init(c, &key, snd_dir->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs, plen); + if (err) + goto out_ro; + } + + finish_reservation(c); + + mark_inode_clean(c, ubifs_inode(fst_dir)); + if (twoparents) + mark_inode_clean(c, ubifs_inode(snd_dir)); + kfree(dent1); + return 0; + +out_release: + release_head(c, BASEHD); +out_ro: + ubifs_ro_mode(c, err); + finish_reservation(c); +out_free: + kfree(dent1); + return err; +} + +/** * ubifs_jnl_rename - rename a directory entry. * @c: UBIFS file-system description object * @old_dir: parent inode of directory entry to rename |