btrfs: assert delayed refs lock is held at find_first_ref_head()

The delayed refs lock must be held when calling find_first_ref_head(), so
assert that it's being held.

Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 9f8853fb9fa6626766375250a5e95e698a9d389c..f74154c56432045a024f1186ac00e19d1001220f 100644 (file)
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -384,6 +384,8 @@ static struct btrfs_delayed_ref_head *find_first_ref_head(
        struct rb_node *n;
        struct btrfs_delayed_ref_head *entry;
 
+       lockdep_assert_held(&dr->lock);
+
        n = rb_first_cached(&dr->href_root);
        if (!n)
                return NULL;