diff options
Diffstat (limited to 'fs/ubifs/dir.c')
-rw-r--r-- | fs/ubifs/dir.c | 120 |
1 files changed, 101 insertions, 19 deletions
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 8460f481eeb9..e0282534f170 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -301,8 +301,8 @@ out_budg: return err; } -static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry, - umode_t mode) +static int do_tmpfile(struct inode *dir, struct dentry *dentry, + umode_t mode, struct inode **whiteout) { struct inode *inode; struct ubifs_info *c = dir->i_sb->s_fs_info; @@ -336,14 +336,27 @@ static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry, } ui = ubifs_inode(inode); + if (whiteout) { + init_special_inode(inode, inode->i_mode, WHITEOUT_DEV); + ubifs_assert(inode->i_op == &ubifs_file_inode_operations); + } + err = ubifs_init_security(dir, inode, &dentry->d_name); if (err) goto out_inode; mutex_lock(&ui->ui_mutex); insert_inode_hash(inode); - d_tmpfile(dentry, inode); + + if (whiteout) { + mark_inode_dirty(inode); + drop_nlink(inode); + *whiteout = inode; + } else { + d_tmpfile(dentry, inode); + } ubifs_assert(ui->dirty); + instantiated = 1; mutex_unlock(&ui->ui_mutex); @@ -371,6 +384,12 @@ out_budg: return err; } +static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry, + umode_t mode) +{ + return do_tmpfile(dir, dentry, mode, NULL); +} + /** * vfs_dent_type - get VFS directory entry type. * @type: UBIFS directory entry type @@ -997,37 +1016,43 @@ out_budg: } /** - * lock_3_inodes - a wrapper for locking three UBIFS inodes. + * lock_4_inodes - a wrapper for locking three UBIFS inodes. * @inode1: first inode * @inode2: second inode * @inode3: third inode + * @inode4: fouth inode * * This function is used for 'ubifs_rename()' and @inode1 may be the same as - * @inode2 whereas @inode3 may be %NULL. + * @inode2 whereas @inode3 and @inode4 may be %NULL. * * We do not implement any tricks to guarantee strict lock ordering, because * VFS has already done it for us on the @i_mutex. So this is just a simple * wrapper function. */ -static void lock_3_inodes(struct inode *inode1, struct inode *inode2, - struct inode *inode3) +static void lock_4_inodes(struct inode *inode1, struct inode *inode2, + struct inode *inode3, struct inode *inode4) { mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1); if (inode2 != inode1) mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2); if (inode3) mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3); + if (inode4) + mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4); } /** - * unlock_3_inodes - a wrapper for unlocking three UBIFS inodes for rename. + * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename. * @inode1: first inode * @inode2: second inode * @inode3: third inode + * @inode4: fouth inode */ -static void unlock_3_inodes(struct inode *inode1, struct inode *inode2, - struct inode *inode3) +static void unlock_4_inodes(struct inode *inode1, struct inode *inode2, + struct inode *inode3, struct inode *inode4) { + if (inode4) + mutex_unlock(&ubifs_inode(inode4)->ui_mutex); if (inode3) mutex_unlock(&ubifs_inode(inode3)->ui_mutex); if (inode1 != inode2) @@ -1036,12 +1061,15 @@ static void unlock_3_inodes(struct inode *inode1, struct inode *inode2, } static int ubifs_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) { struct ubifs_info *c = old_dir->i_sb->s_fs_info; struct inode *old_inode = d_inode(old_dentry); struct inode *new_inode = d_inode(new_dentry); + struct inode *whiteout = NULL; struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode); + struct ubifs_inode *whiteout_ui = NULL; int err, release, sync = 0, move = (new_dir != old_dir); int is_dir = S_ISDIR(old_inode->i_mode); int unlink = !!new_inode; @@ -1063,15 +1091,18 @@ static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry, * separately. */ - dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu", + dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x", old_dentry, old_inode->i_ino, old_dir->i_ino, - new_dentry, new_dir->i_ino); + new_dentry, new_dir->i_ino, flags); + + if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT)) + return -EINVAL; + ubifs_assert(inode_is_locked(old_dir)); ubifs_assert(inode_is_locked(new_dir)); if (unlink) ubifs_assert(inode_is_locked(new_inode)); - if (unlink && is_dir) { err = check_dir_empty(c, new_inode); if (err) @@ -1087,7 +1118,32 @@ static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry, return err; } - lock_3_inodes(old_dir, new_dir, new_inode); + if (flags & RENAME_WHITEOUT) { + union ubifs_dev_desc *dev = NULL; + + dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS); + if (!dev) { + ubifs_release_budget(c, &req); + ubifs_release_budget(c, &ino_req); + return -ENOMEM; + } + + err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout); + if (err) { + ubifs_release_budget(c, &req); + ubifs_release_budget(c, &ino_req); + kfree(dev); + return err; + } + + whiteout->i_state |= I_LINKABLE; + whiteout_ui = ubifs_inode(whiteout); + whiteout_ui->data = dev; + whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0)); + ubifs_assert(!whiteout_ui->dirty); + } + + lock_4_inodes(old_dir, new_dir, new_inode, whiteout); /* * Like most other Unix systems, set the @i_ctime for inodes on a @@ -1157,12 +1213,34 @@ static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry, if (unlink && IS_SYNC(new_inode)) sync = 1; } - err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry, + + if (whiteout) { + struct ubifs_budget_req wht_req = { .dirtied_ino = 1, + .dirtied_ino_d = \ + ALIGN(ubifs_inode(whiteout)->data_len, 8) }; + + err = ubifs_budget_space(c, &wht_req); + if (err) { + ubifs_release_budget(c, &req); + ubifs_release_budget(c, &ino_req); + kfree(whiteout_ui->data); + whiteout_ui->data_len = 0; + iput(whiteout); + return err; + } + + inc_nlink(whiteout); + mark_inode_dirty(whiteout); + whiteout->i_state &= ~I_LINKABLE; + iput(whiteout); + } + + err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry, whiteout, sync); if (err) goto out_cancel; - unlock_3_inodes(old_dir, new_dir, new_inode); + unlock_4_inodes(old_dir, new_dir, new_inode, whiteout); ubifs_release_budget(c, &req); mutex_lock(&old_inode_ui->ui_mutex); @@ -1195,7 +1273,11 @@ out_cancel: inc_nlink(old_dir); } } - unlock_3_inodes(old_dir, new_dir, new_inode); + if (whiteout) { + drop_nlink(whiteout); + iput(whiteout); + } + unlock_4_inodes(old_dir, new_dir, new_inode, whiteout); ubifs_release_budget(c, &ino_req); ubifs_release_budget(c, &req); return err; @@ -1249,7 +1331,7 @@ const struct inode_operations ubifs_dir_inode_operations = { .mkdir = ubifs_mkdir, .rmdir = ubifs_rmdir, .mknod = ubifs_mknod, - .rename = ubifs_rename, + .rename2 = ubifs_rename, .setattr = ubifs_setattr, .getattr = ubifs_getattr, .setxattr = generic_setxattr, |