From 3b9d4ed26680771295d904a6b83e88e620780893 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sat, 25 Apr 2009 22:54:04 -0400 Subject: ext4: Replace lock/unlock_super() with an explicit lock for the orphan list Use a separate lock to protect the orphan list, so we can stop overloading the use of lock_super(). Signed-off-by: "Theodore Ts'o" --- fs/ext4/namei.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) (limited to 'fs/ext4/namei.c') diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 22098e1cd08..8018e49a728 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1997,7 +1997,7 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode) if (!ext4_handle_valid(handle)) return 0; - lock_super(sb); + mutex_lock(&EXT4_SB(sb)->s_orphan_lock); if (!list_empty(&EXT4_I(inode)->i_orphan)) goto out_unlock; @@ -2006,9 +2006,13 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode) /* @@@ FIXME: Observation from aviro: * I think I can trigger J_ASSERT in ext4_orphan_add(). We block - * here (on lock_super()), so race with ext4_link() which might bump + * here (on s_orphan_lock), so race with ext4_link() which might bump * ->i_nlink. For, say it, character device. Not a regular file, * not a directory, not a symlink and ->i_nlink > 0. + * + * tytso, 4/25/2009: I'm not sure how that could happen; + * shouldn't the fs core protect us from these sort of + * unlink()/link() races? */ J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); @@ -2045,7 +2049,7 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode) jbd_debug(4, "orphan inode %lu will point to %d\n", inode->i_ino, NEXT_ORPHAN(inode)); out_unlock: - unlock_super(sb); + mutex_unlock(&EXT4_SB(sb)->s_orphan_lock); ext4_std_error(inode->i_sb, err); return err; } @@ -2066,11 +2070,9 @@ int ext4_orphan_del(handle_t *handle, struct inode *inode) if (!ext4_handle_valid(handle)) return 0; - lock_super(inode->i_sb); - if (list_empty(&ei->i_orphan)) { - unlock_super(inode->i_sb); - return 0; - } + mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock); + if (list_empty(&ei->i_orphan)) + goto out; ino_next = NEXT_ORPHAN(inode); prev = ei->i_orphan.prev; @@ -2120,7 +2122,7 @@ int ext4_orphan_del(handle_t *handle, struct inode *inode) out_err: ext4_std_error(inode->i_sb, err); out: - unlock_super(inode->i_sb); + mutex_unlock(&EXT4_SB(inode->i_sb)->s_orphan_lock); return err; out_brelse: -- cgit v1.2.3