From: Bharata B Rao <[EMAIL PROTECTED]> Subject: ext3 whiteout support
Introduce whiteout support for ext3. Signed-off-by: Bharata B Rao <[EMAIL PROTECTED]> Signed-off-by: Jan Blunck <[EMAIL PROTECTED]> --- fs/ext3/dir.c | 2 - fs/ext3/namei.c | 62 ++++++++++++++++++++++++++++++++++++++++++++---- fs/ext3/super.c | 11 +++++++- include/linux/ext3_fs.h | 5 +++ 4 files changed, 72 insertions(+), 8 deletions(-) --- a/fs/ext3/dir.c +++ b/fs/ext3/dir.c @@ -29,7 +29,7 @@ #include <linux/rbtree.h> static unsigned char ext3_filetype_table[] = { - DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK + DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK, DT_WHT }; static int ext3_readdir(struct file *, void *, filldir_t); --- a/fs/ext3/namei.c +++ b/fs/ext3/namei.c @@ -1071,6 +1071,7 @@ static unsigned char ext3_type_by_mode[S [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO, [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK, [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK, + [S_IFWHT >> S_SHIFT] = EXT3_FT_WHT, }; static inline void ext3_set_de_type(struct super_block *sb, @@ -1786,7 +1787,7 @@ out_stop: /* * routine to check that the specified directory is empty (for rmdir) */ -static int empty_dir (struct inode * inode) +static int empty_dir (handle_t *handle, struct inode * inode) { unsigned long offset; struct buffer_head * bh; @@ -1848,8 +1849,28 @@ static int empty_dir (struct inode * ino continue; } if (le32_to_cpu(de->inode)) { - brelse (bh); - return 0; + /* If this is a whiteout, remove it */ + if (de->file_type == EXT3_FT_WHT) { + unsigned long ino = le32_to_cpu(de->inode); + struct inode *tmp_inode = iget(inode->i_sb, ino); + if (!tmp_inode) { + brelse (bh); + return 0; + } + + if (ext3_delete_entry(handle, inode, de, bh)) { + iput(tmp_inode); + brelse (bh); + return 0; + } + + tmp_inode->i_ctime = inode->i_ctime; + tmp_inode->i_nlink--; + iput(tmp_inode); + } else { + brelse (bh); + return 0; + } } offset += le16_to_cpu(de->rec_len); de = (struct ext3_dir_entry_2 *) @@ -2031,7 +2052,7 @@ static int ext3_rmdir (struct inode * di goto end_rmdir; retval = -ENOTEMPTY; - if (!empty_dir (inode)) + if (!empty_dir (handle, inode)) goto end_rmdir; retval = ext3_delete_entry(handle, dir, de, bh); @@ -2060,6 +2081,36 @@ end_rmdir: return retval; } +static int ext3_whiteout(struct inode *dir, struct dentry *dentry) +{ + struct inode * inode; + int err, retries = 0; + handle_t *handle; + +retry: + handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + + EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + + 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); + if (IS_ERR(handle)) + return PTR_ERR(handle); + + if (IS_DIRSYNC(dir)) + handle->h_sync = 1; + + inode = ext3_new_inode (handle, dir, S_IFWHT | S_IRUGO); + err = PTR_ERR(inode); + if (IS_ERR(inode)) + goto out_stop; + + err = ext3_add_nondir(handle, dentry, inode); + +out_stop: + ext3_journal_stop(handle); + if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) + goto retry; + return err; +} + static int ext3_unlink(struct inode * dir, struct dentry *dentry) { int retval; @@ -2261,7 +2312,7 @@ static int ext3_rename (struct inode * o if (S_ISDIR(old_inode->i_mode)) { if (new_inode) { retval = -ENOTEMPTY; - if (!empty_dir (new_inode)) + if (!empty_dir (handle, new_inode)) goto end_rename; } retval = -EIO; @@ -2377,6 +2428,7 @@ const struct inode_operations ext3_dir_i .mkdir = ext3_mkdir, .rmdir = ext3_rmdir, .mknod = ext3_mknod, + .whiteout = ext3_whiteout, .rename = ext3_rename, .setattr = ext3_setattr, #ifdef CONFIG_EXT3_FS_XATTR --- a/fs/ext3/super.c +++ b/fs/ext3/super.c @@ -1492,6 +1492,15 @@ static int ext3_fill_super (struct super sb->s_flags = (sb->s_flags & ~MS_POSIXACL) | ((sbi->s_mount_opt & EXT3_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0); + if ((sb->s_flags & MS_UNION) && !(sb->s_flags & MS_RDONLY)) { + if (!EXT3_HAS_INCOMPAT_FEATURE(sb, + EXT3_FEATURE_INCOMPAT_WHITEOUT)) { + sb->s_flags |= MS_RDONLY; + ext3_warning(sb, __FUNCTION__, + "no whiteout support, mounting filesystem read-only"); + } + } + if (le32_to_cpu(es->s_rev_level) == EXT3_GOOD_OLD_REV && (EXT3_HAS_COMPAT_FEATURE(sb, ~0U) || EXT3_HAS_RO_COMPAT_FEATURE(sb, ~0U) || @@ -2748,7 +2757,7 @@ static struct file_system_type ext3_fs_t .name = "ext3", .get_sb = ext3_get_sb, .kill_sb = kill_block_super, - .fs_flags = FS_REQUIRES_DEV, + .fs_flags = FS_REQUIRES_DEV | FS_WHT, }; static int __init init_ext3_fs(void) --- a/include/linux/ext3_fs.h +++ b/include/linux/ext3_fs.h @@ -63,6 +63,7 @@ #define EXT3_UNDEL_DIR_INO 6 /* Undelete directory inode */ #define EXT3_RESIZE_INO 7 /* Reserved group descriptors inode */ #define EXT3_JOURNAL_INO 8 /* Journal inode */ +#define EXT3_WHT_INO 9 /* Whiteout inode */ /* First non-reserved inode for old ext3 filesystems */ #define EXT3_GOOD_OLD_FIRST_INO 11 @@ -582,6 +583,7 @@ static inline int ext3_valid_inum(struct #define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */ #define EXT3_FEATURE_INCOMPAT_META_BG 0x0010 +#define EXT3_FEATURE_INCOMPAT_WHITEOUT 0x0020 #define EXT3_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR #define EXT3_FEATURE_INCOMPAT_SUPP (EXT3_FEATURE_INCOMPAT_FILETYPE| \ @@ -648,8 +650,9 @@ struct ext3_dir_entry_2 { #define EXT3_FT_FIFO 5 #define EXT3_FT_SOCK 6 #define EXT3_FT_SYMLINK 7 +#define EXT3_FT_WHT 8 -#define EXT3_FT_MAX 8 +#define EXT3_FT_MAX 9 /* * EXT3_DIR_PAD defines the directory entries boundaries - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html