468 	struct rb_node	*n;  in rb_first()  local
470 	n = root->rb_node;  in rb_first()
471 	if (!n)  in rb_first()
473 	while (n->rb_left)  in rb_first()
474 		n = n->rb_left;  in rb_first()
475 	return n;  in rb_first()
481 	struct rb_node	*n;  in rb_last()  local
483 	n = root->rb_node;  in rb_last()
484 	if (!n)  in rb_last()
486 	while (n->rb_right)  in rb_last()
487 		n = n->rb_right;  in rb_last()
488 	return n;  in rb_last()