diff options
| -rw-r--r-- | fs/ext4/namei.c | 60 | ||||
| -rw-r--r-- | include/linux/ext4_fs.h | 4 |
2 files changed, 49 insertions, 15 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 40106b7ea4b..da224974af7 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1629,6 +1629,35 @@ static int ext4_delete_entry (handle_t *handle, return -ENOENT; } +/* + * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2, + * since this indicates that nlinks count was previously 1. + */ +static void ext4_inc_count(handle_t *handle, struct inode *inode) +{ + inc_nlink(inode); + if (is_dx(inode) && inode->i_nlink > 1) { + /* limit is 16-bit i_links_count */ + if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) { + inode->i_nlink = 1; + EXT4_SET_RO_COMPAT_FEATURE(inode->i_sb, + EXT4_FEATURE_RO_COMPAT_DIR_NLINK); + } + } +} + +/* + * If a directory had nlink == 1, then we should let it be 1. This indicates + * directory has >EXT4_LINK_MAX subdirs. + */ +static void ext4_dec_count(handle_t *handle, struct inode *inode) +{ + drop_nlink(inode); + if (S_ISDIR(inode->i_mode) && inode->i_nlink == 0) + inc_nlink(inode); +} + + static int ext4_add_nondir(handle_t *handle, struct dentry *dentry, struct inode *inode) { @@ -1725,7 +1754,7 @@ static int ext4_mkdir(struct inode * dir, struct dentry * dentry, int mode) struct ext4_dir_entry_2 * de; int err, retries = 0; - if (dir->i_nlink >= EXT4_LINK_MAX) + if (EXT4_DIR_LINK_MAX(dir)) return -EMLINK; retry: @@ -1748,7 +1777,7 @@ retry: inode->i_size = EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize; dir_block = ext4_bread (handle, inode, 0, 1, &err); if (!dir_block) { - drop_nlink(inode); /* is this nlink == 0? */ + ext4_dec_count(handle, inode); /* is this nlink == 0? */ ext4_mark_inode_dirty(handle, inode); iput (inode); goto out_stop; @@ -1780,7 +1809,7 @@ retry: iput (inode); goto out_stop; } - inc_nlink(dir); + ext4_inc_count(handle, dir); ext4_update_dx_flag(dir); ext4_mark_inode_dirty(handle, dir); d_instantiate(dentry, inode); @@ -2045,9 +2074,9 @@ static int ext4_rmdir (struct inode * dir, struct dentry *dentry) retval = ext4_delete_entry(handle, dir, de, bh); if (retval) goto end_rmdir; - if (inode->i_nlink != 2) + if (!EXT4_DIR_LINK_EMPTY(inode)) ext4_warning (inode->i_sb, "ext4_rmdir", - "empty directory has nlink!=2 (%d)", + "empty directory has too many links (%d)", inode->i_nlink); inode->i_version++; clear_nlink(inode); @@ -2058,7 +2087,7 @@ static int ext4_rmdir (struct inode * dir, struct dentry *dentry) ext4_orphan_add(handle, inode); inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode); ext4_mark_inode_dirty(handle, inode); - drop_nlink(dir); + ext4_dec_count(handle, dir); ext4_update_dx_flag(dir); ext4_mark_inode_dirty(handle, dir); @@ -2109,7 +2138,7 @@ static int ext4_unlink(struct inode * dir, struct dentry *dentry) dir->i_ctime = dir->i_mtime = ext4_current_time(dir); ext4_update_dx_flag(dir); ext4_mark_inode_dirty(handle, dir); - drop_nlink(inode); + ext4_dec_count(handle, inode); if (!inode->i_nlink) ext4_orphan_add(handle, inode); inode->i_ctime = ext4_current_time(inode); @@ -2159,7 +2188,7 @@ retry: err = __page_symlink(inode, symname, l, mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS); if (err) { - drop_nlink(inode); + ext4_dec_count(handle, inode); ext4_mark_inode_dirty(handle, inode); iput (inode); goto out_stop; @@ -2185,8 +2214,9 @@ static int ext4_link (struct dentry * old_dentry, struct inode *inode = old_dentry->d_inode; int err, retries = 0; - if (inode->i_nlink >= EXT4_LINK_MAX) + if (EXT4_DIR_LINK_MAX(inode)) return -EMLINK; + /* * Return -ENOENT if we've raced with unlink and i_nlink is 0. Doing * otherwise has the potential to corrupt the orphan inode list. @@ -2204,7 +2234,7 @@ retry: handle->h_sync = 1; inode->i_ctime = ext4_current_time(inode); - inc_nlink(inode); + ext4_inc_count(handle, inode); atomic_inc(&inode->i_count); err = ext4_add_nondir(handle, dentry, inode); @@ -2337,7 +2367,7 @@ static int ext4_rename (struct inode * old_dir, struct dentry *old_dentry, } if (new_inode) { - drop_nlink(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); @@ -2348,11 +2378,13 @@ static int ext4_rename (struct inode * old_dir, struct dentry *old_dentry, PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino); BUFFER_TRACE(dir_bh, "call ext4_journal_dirty_metadata"); ext4_journal_dirty_metadata(handle, dir_bh); - drop_nlink(old_dir); + ext4_dec_count(handle, old_dir); if (new_inode) { - drop_nlink(new_inode); + /* checked empty_dir above, can't have another parent, + * ext3_dec_count() won't work for many-linked dirs */ + new_inode->i_nlink = 0; } else { - inc_nlink(new_dir); + ext4_inc_count(handle, new_dir); ext4_update_dx_flag(new_dir); ext4_mark_inode_dirty(handle, new_dir); } diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h index 52dcc24dd98..cdee7aaa57a 100644 --- a/include/linux/ext4_fs.h +++ b/include/linux/ext4_fs.h @@ -71,7 +71,7 @@ /* * Maximal count of links to a file */ -#define EXT4_LINK_MAX 32000 +#define EXT4_LINK_MAX 65000 /* * Macro-instructions used to manage several block sizes @@ -692,6 +692,7 @@ static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino) #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 +#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001 @@ -710,6 +711,7 @@ static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino) EXT4_FEATURE_INCOMPAT_64BIT) #define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \ EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \ + EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \ EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \ EXT4_FEATURE_RO_COMPAT_BTREE_DIR) |