btrfs: assert extent map tree lock in add_extent_mapping

As add_extent_mapping is called from several functions, let's add the
lock annotation. The tree is going to be modified so it must be the
exclusive lock.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 9558d79..9d30acc 100644 (file)
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -384,6 +384,8 @@ int add_extent_mapping(struct extent_map_tree *tree,
 {
        int ret = 0;
 
+       lockdep_assert_held_write(&tree->lock);
+
        ret = tree_insert(&tree->map, em);
        if (ret)
                goto out;