Fix btrfs_inc_ref to add backref hints

	}

	return btrfs_inc_extent_ref(trans, root, root->node->start,

				    root->node->len, owner_objectid,

				    generation, 0, 0);

				    generation, key_objectid, level);

}

int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,

			}

		} else {

			bytenr = btrfs_node_blockptr(buf, i);

			btrfs_node_key_to_cpu(buf, &key, i);

			ret = btrfs_inc_extent_ref(trans, root, bytenr,

					   btrfs_level_size(root, level - 1),

					   root->root_key.objectid,

					   trans->transid, 0, 0);

					   trans->transid, key.objectid,

					   level - 1);

			if (ret) {

				faili = i;

				goto fail;