static void
bch2_btree_insert_keys_interior(struct btree_update *as,
				struct btree_trans *trans,
				struct btree_path *path,
				struct btree *b,
				struct keylist *keys)
static void
bch2_btree_insert_keys_interior(struct btree_update *as,
				struct btree_trans *trans,
				struct btree_path *path,
				struct btree *b,
				struct btree_node_iter node_iter,
				struct keylist *keys)