From f87135762de4328c6f17897e803e6909bc056feb Mon Sep 17 00:00:00 2001 From: David Howells Date: Sat, 28 Oct 2006 10:38:46 -0700 Subject: [PATCH] [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 --- fs/dcache.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index a5b76b647c6..fd4a428998e 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); } /*