From: David Howells Date: Sat, 28 Oct 2006 17:38:46 +0000 (-0700) Subject: [PATCH] VFS: Fix an error in unused dentry counting X-Git-Tag: v3.12-rc1~32144^2~7^2~29 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f87135762de4328c6f17897e803e6909bc056feb;p=kernel%2Fkernel-generic.git [PATCH] VFS: Fix an error in unused dentry counting With Vasily Averin Fix an error in unused dentry counting in shrink_dcache_for_umount_subtree() in which the count is modified without the dcache_lock held. Signed-off-by: David Howells Cc: Vasily Averin Cc: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/dcache.c b/fs/dcache.c index a5b76b6..fd4a428 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -557,6 +557,7 @@ repeat: static void shrink_dcache_for_umount_subtree(struct dentry *dentry) { struct dentry *parent; + unsigned detached = 0; BUG_ON(!IS_ROOT(dentry)); @@ -621,7 +622,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) atomic_dec(&parent->d_count); list_del(&dentry->d_u.d_child); - dentry_stat.nr_dentry--; /* For d_free, below */ + detached++; inode = dentry->d_inode; if (inode) { @@ -639,7 +640,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) * otherwise we ascend to the parent and move to the * next sibling if there is one */ if (!parent) - return; + goto out; dentry = parent; @@ -648,6 +649,11 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) dentry = list_entry(dentry->d_subdirs.next, struct dentry, d_u.d_child); } +out: + /* several dentries were freed, need to correct nr_dentry */ + spin_lock(&dcache_lock); + dentry_stat.nr_dentry -= detached; + spin_unlock(&dcache_lock); } /*