IORING_MSG_RING_FLAGS_PASS
if (!(msg->flags & IORING_MSG_RING_FLAGS_PASS))
if (msg->src_fd || msg->flags & ~IORING_MSG_RING_FLAGS_PASS)
if (!(msg->flags & IORING_MSG_RING_FLAGS_PASS) && msg->dst_fd)
IORING_MSG_RING_FLAGS_PASS)