diff options
Diffstat (limited to 'fs/ext4/namei.c')
-rw-r--r-- | fs/ext4/namei.c | 480 |
1 files changed, 349 insertions, 131 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index d050e04..1cb84f7 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3000,6 +3000,154 @@ static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, return ext4_get_first_inline_block(inode, parent_de, retval); } +struct ext4_renament { + struct inode *dir; + struct dentry *dentry; + struct inode *inode; + bool is_dir; + int dir_nlink_delta; + + /* entry for "dentry" */ + struct buffer_head *bh; + struct ext4_dir_entry_2 *de; + int inlined; + + /* entry for ".." in inode if it's a directory */ + struct buffer_head *dir_bh; + struct ext4_dir_entry_2 *parent_de; + int dir_inlined; +}; + +static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) +{ + int retval; + + ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, + &retval, &ent->parent_de, + &ent->dir_inlined); + if (!ent->dir_bh) + return retval; + if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) + return -EIO; + BUFFER_TRACE(ent->dir_bh, "get_write_access"); + return ext4_journal_get_write_access(handle, ent->dir_bh); +} + +static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, + unsigned dir_ino) +{ + int retval; + + ent->parent_de->inode = cpu_to_le32(dir_ino); + BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); + if (!ent->dir_inlined) { + if (is_dx(ent->inode)) { + retval = ext4_handle_dirty_dx_node(handle, + ent->inode, + ent->dir_bh); + } else { + retval = ext4_handle_dirty_dirent_node(handle, + ent->inode, + ent->dir_bh); + } + } else { + retval = ext4_mark_inode_dirty(handle, ent->inode); + } + if (retval) { + ext4_std_error(ent->dir->i_sb, retval); + return retval; + } + return 0; +} + +static int ext4_setent(handle_t *handle, struct ext4_renament *ent, + unsigned ino, unsigned file_type) +{ + int retval; + + BUFFER_TRACE(ent->bh, "get write access"); + retval = ext4_journal_get_write_access(handle, ent->bh); + if (retval) + return retval; + ent->de->inode = cpu_to_le32(ino); + if (EXT4_HAS_INCOMPAT_FEATURE(ent->dir->i_sb, + EXT4_FEATURE_INCOMPAT_FILETYPE)) + ent->de->file_type = file_type; + ent->dir->i_version++; + ent->dir->i_ctime = ent->dir->i_mtime = + ext4_current_time(ent->dir); + ext4_mark_inode_dirty(handle, ent->dir); + BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); + if (!ent->inlined) { + retval = ext4_handle_dirty_dirent_node(handle, + ent->dir, ent->bh); + if (unlikely(retval)) { + ext4_std_error(ent->dir->i_sb, retval); + return retval; + } + } + brelse(ent->bh); + ent->bh = NULL; + + return 0; +} + +static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, + const struct qstr *d_name) +{ + int retval = -ENOENT; + struct buffer_head *bh; + struct ext4_dir_entry_2 *de; + + bh = ext4_find_entry(dir, d_name, &de, NULL); + if (bh) { + retval = ext4_delete_entry(handle, dir, de, bh); + brelse(bh); + } + return retval; +} + +static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent) +{ + int retval; + /* + * ent->de could have moved from under us during htree split, so make + * sure that we are deleting the right entry. We might also be pointing + * to a stale entry in the unused part of ent->bh so just checking inum + * and the name isn't enough. + */ + if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || + ent->de->name_len != ent->dentry->d_name.len || + strncmp(ent->de->name, ent->dentry->d_name.name, + ent->de->name_len)) { + retval = ext4_find_delete_entry(handle, ent->dir, + &ent->dentry->d_name); + } else { + retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); + if (retval == -ENOENT) { + retval = ext4_find_delete_entry(handle, ent->dir, + &ent->dentry->d_name); + } + } + + if (retval) { + ext4_warning(ent->dir->i_sb, + "Deleting old file (%lu), %d, error=%d", + ent->dir->i_ino, ent->dir->i_nlink, retval); + } +} + +static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) +{ + if (ent->dir_nlink_delta) { + if (ent->dir_nlink_delta == -1) + ext4_dec_count(handle, ent->dir); + else + ext4_inc_count(handle, ent->dir); + ext4_mark_inode_dirty(handle, ent->dir); + } +} + /* * Anybody can rename anything with this: the permission checks are left to the * higher-level routines. @@ -3012,198 +3160,267 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { handle_t *handle = NULL; - struct inode *old_inode, *new_inode; - struct buffer_head *old_bh, *new_bh, *dir_bh; - struct ext4_dir_entry_2 *old_de, *new_de; + struct ext4_renament old = { + .dir = old_dir, + .dentry = old_dentry, + .inode = old_dentry->d_inode, + }; + struct ext4_renament new = { + .dir = new_dir, + .dentry = new_dentry, + .inode = new_dentry->d_inode, + }; int retval; - int inlined = 0, new_inlined = 0; - struct ext4_dir_entry_2 *parent_de; - dquot_initialize(old_dir); - dquot_initialize(new_dir); - - old_bh = new_bh = dir_bh = NULL; + dquot_initialize(old.dir); + dquot_initialize(new.dir); /* Initialize quotas before so that eventual writes go * in separate transaction */ - if (new_dentry->d_inode) - dquot_initialize(new_dentry->d_inode); + if (new.inode) + dquot_initialize(new.inode); - old_bh = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de, NULL); + old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); /* * Check for inode number is _not_ due to possible IO errors. * We might rmdir the source, keep it as pwd of some process * and merrily kill the link to whatever was created under the * same name. Goodbye sticky bit ;-< */ - old_inode = old_dentry->d_inode; retval = -ENOENT; - if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino) + if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) goto end_rename; - new_inode = new_dentry->d_inode; - new_bh = ext4_find_entry(new_dir, &new_dentry->d_name, - &new_de, &new_inlined); - if (new_bh) { - if (!new_inode) { - brelse(new_bh); - new_bh = NULL; + new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, + &new.de, &new.inlined); + if (new.bh) { + if (!new.inode) { + brelse(new.bh); + new.bh = NULL; } } - if (new_inode && !test_opt(new_dir->i_sb, NO_AUTO_DA_ALLOC)) - ext4_alloc_da_blocks(old_inode); + if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) + ext4_alloc_da_blocks(old.inode); - handle = ext4_journal_start(old_dir, EXT4_HT_DIR, - (2 * EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) + + handle = ext4_journal_start(old.dir, EXT4_HT_DIR, + (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); if (IS_ERR(handle)) return PTR_ERR(handle); - if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) + if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) ext4_handle_sync(handle); - if (S_ISDIR(old_inode->i_mode)) { - if (new_inode) { + if (S_ISDIR(old.inode->i_mode)) { + if (new.inode) { retval = -ENOTEMPTY; - if (!empty_dir(new_inode)) + if (!empty_dir(new.inode)) + goto end_rename; + } else { + retval = -EMLINK; + if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) goto end_rename; } - retval = -EIO; - dir_bh = ext4_get_first_dir_block(handle, old_inode, - &retval, &parent_de, - &inlined); - if (!dir_bh) - goto end_rename; - if (le32_to_cpu(parent_de->inode) != old_dir->i_ino) - goto end_rename; - retval = -EMLINK; - if (!new_inode && new_dir != old_dir && - EXT4_DIR_LINK_MAX(new_dir)) - goto end_rename; - BUFFER_TRACE(dir_bh, "get_write_access"); - retval = ext4_journal_get_write_access(handle, dir_bh); + retval = ext4_rename_dir_prepare(handle, &old); if (retval) goto end_rename; } - if (!new_bh) { - retval = ext4_add_entry(handle, new_dentry, old_inode); + if (!new.bh) { + retval = ext4_add_entry(handle, new.dentry, old.inode); if (retval) goto end_rename; } else { - BUFFER_TRACE(new_bh, "get write access"); - retval = ext4_journal_get_write_access(handle, new_bh); + retval = ext4_setent(handle, &new, + old.inode->i_ino, old.de->file_type); if (retval) goto end_rename; - new_de->inode = cpu_to_le32(old_inode->i_ino); - if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb, - EXT4_FEATURE_INCOMPAT_FILETYPE)) - new_de->file_type = old_de->file_type; - new_dir->i_version++; - new_dir->i_ctime = new_dir->i_mtime = - ext4_current_time(new_dir); - ext4_mark_inode_dirty(handle, new_dir); - BUFFER_TRACE(new_bh, "call ext4_handle_dirty_metadata"); - if (!new_inlined) { - retval = ext4_handle_dirty_dirent_node(handle, - new_dir, new_bh); - if (unlikely(retval)) { - ext4_std_error(new_dir->i_sb, retval); - goto end_rename; - } - } - brelse(new_bh); - new_bh = NULL; } /* * Like most other Unix systems, set the ctime for inodes on a * rename. */ - old_inode->i_ctime = ext4_current_time(old_inode); - ext4_mark_inode_dirty(handle, old_inode); + old.inode->i_ctime = ext4_current_time(old.inode); + ext4_mark_inode_dirty(handle, old.inode); /* * ok, that's it */ - if (le32_to_cpu(old_de->inode) != old_inode->i_ino || - old_de->name_len != old_dentry->d_name.len || - strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) || - (retval = ext4_delete_entry(handle, old_dir, - old_de, old_bh)) == -ENOENT) { - /* old_de could have moved from under us during htree split, so - * make sure that we are deleting the right entry. We might - * also be pointing to a stale entry in the unused part of - * old_bh so just checking inum and the name isn't enough. */ - struct buffer_head *old_bh2; - struct ext4_dir_entry_2 *old_de2; - - old_bh2 = ext4_find_entry(old_dir, &old_dentry->d_name, - &old_de2, NULL); - if (old_bh2) { - retval = ext4_delete_entry(handle, old_dir, - old_de2, old_bh2); - brelse(old_bh2); - } + ext4_rename_delete(handle, &old); + + if (new.inode) { + ext4_dec_count(handle, new.inode); + new.inode->i_ctime = ext4_current_time(new.inode); } - if (retval) { - ext4_warning(old_dir->i_sb, - "Deleting old file (%lu), %d, error=%d", - old_dir->i_ino, old_dir->i_nlink, retval); - } - - if (new_inode) { - ext4_dec_count(handle, new_inode); - new_inode->i_ctime = ext4_current_time(new_inode); - } - old_dir->i_ctime = old_dir->i_mtime = ext4_current_time(old_dir); - ext4_update_dx_flag(old_dir); - if (dir_bh) { - parent_de->inode = cpu_to_le32(new_dir->i_ino); - BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata"); - if (!inlined) { - if (is_dx(old_inode)) { - retval = ext4_handle_dirty_dx_node(handle, - old_inode, - dir_bh); - } else { - retval = ext4_handle_dirty_dirent_node(handle, - old_inode, dir_bh); - } - } else { - retval = ext4_mark_inode_dirty(handle, old_inode); - } - if (retval) { - ext4_std_error(old_dir->i_sb, retval); + old.dir->i_ctime = old.dir->i_mtime = ext4_current_time(old.dir); + ext4_update_dx_flag(old.dir); + if (old.dir_bh) { + retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); + if (retval) goto end_rename; - } - ext4_dec_count(handle, old_dir); - if (new_inode) { + + ext4_dec_count(handle, old.dir); + if (new.inode) { /* checked empty_dir above, can't have another parent, * ext4_dec_count() won't work for many-linked dirs */ - clear_nlink(new_inode); + clear_nlink(new.inode); } else { - ext4_inc_count(handle, new_dir); - ext4_update_dx_flag(new_dir); - ext4_mark_inode_dirty(handle, new_dir); + ext4_inc_count(handle, new.dir); + ext4_update_dx_flag(new.dir); + ext4_mark_inode_dirty(handle, new.dir); } } - ext4_mark_inode_dirty(handle, old_dir); - if (new_inode) { - ext4_mark_inode_dirty(handle, new_inode); - if (!new_inode->i_nlink) - ext4_orphan_add(handle, new_inode); + ext4_mark_inode_dirty(handle, old.dir); + if (new.inode) { + ext4_mark_inode_dirty(handle, new.inode); + if (!new.inode->i_nlink) + ext4_orphan_add(handle, new.inode); } retval = 0; end_rename: - brelse(dir_bh); - brelse(old_bh); - brelse(new_bh); + brelse(old.dir_bh); + brelse(old.bh); + brelse(new.bh); if (handle) ext4_journal_stop(handle); return retval; } +static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + handle_t *handle = NULL; + struct ext4_renament old = { + .dir = old_dir, + .dentry = old_dentry, + .inode = old_dentry->d_inode, + }; + struct ext4_renament new = { + .dir = new_dir, + .dentry = new_dentry, + .inode = new_dentry->d_inode, + }; + u8 new_file_type; + int retval; + + dquot_initialize(old.dir); + dquot_initialize(new.dir); + + old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, + &old.de, &old.inlined); + /* + * Check for inode number is _not_ due to possible IO errors. + * We might rmdir the source, keep it as pwd of some process + * and merrily kill the link to whatever was created under the + * same name. Goodbye sticky bit ;-< + */ + retval = -ENOENT; + if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) + goto end_rename; + + new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, + &new.de, &new.inlined); + + /* RENAME_EXCHANGE case: old *and* new must both exist */ + if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) + goto end_rename; + + handle = ext4_journal_start(old.dir, EXT4_HT_DIR, + (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + + 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); + if (IS_ERR(handle)) + return PTR_ERR(handle); + + if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) + ext4_handle_sync(handle); + + if (S_ISDIR(old.inode->i_mode)) { + old.is_dir = true; + retval = ext4_rename_dir_prepare(handle, &old); + if (retval) + goto end_rename; + } + if (S_ISDIR(new.inode->i_mode)) { + new.is_dir = true; + retval = ext4_rename_dir_prepare(handle, &new); + if (retval) + goto end_rename; + } + + /* + * Other than the special case of overwriting a directory, parents' + * nlink only needs to be modified if this is a cross directory rename. + */ + if (old.dir != new.dir && old.is_dir != new.is_dir) { + old.dir_nlink_delta = old.is_dir ? -1 : 1; + new.dir_nlink_delta = -old.dir_nlink_delta; + retval = -EMLINK; + if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || + (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) + goto end_rename; + } + + new_file_type = new.de->file_type; + retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); + if (retval) + goto end_rename; + + retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); + if (retval) + goto end_rename; + + /* + * Like most other Unix systems, set the ctime for inodes on a + * rename. + */ + old.inode->i_ctime = ext4_current_time(old.inode); + new.inode->i_ctime = ext4_current_time(new.inode); + ext4_mark_inode_dirty(handle, old.inode); + ext4_mark_inode_dirty(handle, new.inode); + + if (old.dir_bh) { + retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); + if (retval) + goto end_rename; + } + if (new.dir_bh) { + retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); + if (retval) + goto end_rename; + } + ext4_update_dir_count(handle, &old); + ext4_update_dir_count(handle, &new); + retval = 0; + +end_rename: + brelse(old.dir_bh); + brelse(new.dir_bh); + brelse(old.bh); + brelse(new.bh); + if (handle) + ext4_journal_stop(handle); + return retval; +} + +static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags) +{ + if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) + return -EINVAL; + + if (flags & RENAME_EXCHANGE) { + return ext4_cross_rename(old_dir, old_dentry, + new_dir, new_dentry); + } + /* + * Existence checking was done by the VFS, otherwise "RENAME_NOREPLACE" + * is equivalent to regular rename. + */ + return ext4_rename(old_dir, old_dentry, new_dir, new_dentry); +} + /* * directories can handle most operations... */ @@ -3218,6 +3435,7 @@ const struct inode_operations ext4_dir_inode_operations = { .mknod = ext4_mknod, .tmpfile = ext4_tmpfile, .rename = ext4_rename, + .rename2 = ext4_rename2, .setattr = ext4_setattr, .setxattr = generic_setxattr, .getxattr = generic_getxattr, |