diff options
Diffstat (limited to 'fs/ext4/namei.c')
| -rw-r--r-- | fs/ext4/namei.c | 95 |
1 files changed, 78 insertions, 17 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index adb559de23c1..123798c5ac31 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3148,6 +3148,39 @@ static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) } } +static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, + int credits, handle_t **h) +{ + struct inode *wh; + handle_t *handle; + int retries = 0; + + /* + * for inode block, sb block, group summaries, + * and inode bitmap + */ + credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + + EXT4_XATTR_TRANS_BLOCKS + 4); +retry: + wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, + &ent->dentry->d_name, 0, NULL, + EXT4_HT_DIR, credits); + + handle = ext4_journal_current_handle(); + if (IS_ERR(wh)) { + if (handle) + ext4_journal_stop(handle); + if (PTR_ERR(wh) == -ENOSPC && + ext4_should_retry_alloc(ent->dir->i_sb, &retries)) + goto retry; + } else { + *h = handle; + init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); + wh->i_op = &ext4_special_inode_operations; + } + return wh; +} + /* * Anybody can rename anything with this: the permission checks are left to the * higher-level routines. @@ -3157,7 +3190,8 @@ static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) * This comes from rename(const char *oldpath, const char *newpath) */ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry) + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags) { handle_t *handle = NULL; struct ext4_renament old = { @@ -3172,6 +3206,9 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, }; int force_reread; int retval; + struct inode *whiteout = NULL; + int credits; + u8 old_file_type; dquot_initialize(old.dir); dquot_initialize(new.dir); @@ -3210,11 +3247,17 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, 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) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); - if (IS_ERR(handle)) - return PTR_ERR(handle); + credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + + EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); + if (!(flags & RENAME_WHITEOUT)) { + handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); + if (IS_ERR(handle)) + return PTR_ERR(handle); + } else { + whiteout = ext4_whiteout_for_rename(&old, credits, &handle); + if (IS_ERR(whiteout)) + return PTR_ERR(whiteout); + } if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) ext4_handle_sync(handle); @@ -3242,13 +3285,26 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, */ force_reread = (new.dir->i_ino == old.dir->i_ino && ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); + + old_file_type = old.de->file_type; + if (whiteout) { + /* + * Do this before adding a new entry, so the old entry is sure + * to be still pointing to the valid old entry. + */ + retval = ext4_setent(handle, &old, whiteout->i_ino, + EXT4_FT_CHRDEV); + if (retval) + goto end_rename; + ext4_mark_inode_dirty(handle, whiteout); + } if (!new.bh) { retval = ext4_add_entry(handle, new.dentry, old.inode); if (retval) goto end_rename; } else { retval = ext4_setent(handle, &new, - old.inode->i_ino, old.de->file_type); + old.inode->i_ino, old_file_type); if (retval) goto end_rename; } @@ -3263,10 +3319,12 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, old.inode->i_ctime = ext4_current_time(old.inode); ext4_mark_inode_dirty(handle, old.inode); - /* - * ok, that's it - */ - ext4_rename_delete(handle, &old, force_reread); + if (!whiteout) { + /* + * ok, that's it + */ + ext4_rename_delete(handle, &old, force_reread); + } if (new.inode) { ext4_dec_count(handle, new.inode); @@ -3302,6 +3360,12 @@ end_rename: brelse(old.dir_bh); brelse(old.bh); brelse(new.bh); + if (whiteout) { + if (retval) + drop_nlink(whiteout); + unlock_new_inode(whiteout); + iput(whiteout); + } if (handle) ext4_journal_stop(handle); return retval; @@ -3434,18 +3498,15 @@ 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)) + if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 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); + + return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); } /* |