+int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags)
+{
+ struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
+ struct io_async_msghdr iomsg, *kmsg;
+ struct socket *sock;
+ unsigned flags;
+ int ret, min_ret = 0;
+
+ sock = sock_from_file(req->file);
+ if (unlikely(!sock))
+ return -ENOTSOCK;
+
+ if (req_has_async_data(req)) {
+ kmsg = req->async_data;
+ } else {
+ ret = io_sendmsg_copy_hdr(req, &iomsg);
+ if (ret)
+ return ret;
+ kmsg = &iomsg;
+ }
+
+ if (!(req->flags & REQ_F_POLLED) &&
+ (sr->flags & IORING_RECVSEND_POLL_FIRST))
+ return io_setup_async_msg(req, kmsg, issue_flags);
+
+ flags = sr->msg_flags | MSG_ZEROCOPY;
+ if (issue_flags & IO_URING_F_NONBLOCK)
+ flags |= MSG_DONTWAIT;
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+
+ kmsg->msg.msg_ubuf = &io_notif_to_data(sr->notif)->uarg;
+ kmsg->msg.sg_from_iter = io_sg_from_iter_iovec;
+ ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
+
+ if (unlikely(ret < min_ret)) {
+ if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
+ return io_setup_async_msg(req, kmsg, issue_flags);
+
+ if (ret > 0 && io_net_retry(sock, flags)) {
+ sr->done_io += ret;
+ req->flags |= REQ_F_PARTIAL_IO;
+ return io_setup_async_msg(req, kmsg, issue_flags);
+ }
+ if (ret == -ERESTARTSYS)
+ ret = -EINTR;
+ req_set_fail(req);
+ }
+ /* fast path, check for non-NULL to avoid function call */
+ if (kmsg->free_iov) {
+ kfree(kmsg->free_iov);
+ kmsg->free_iov = NULL;
+ }
+
+ io_netmsg_recycle(req, issue_flags);
+ if (ret >= 0)
+ ret += sr->done_io;
+ else if (sr->done_io)
+ ret = sr->done_io;
+
+ /*
+ * If we're in io-wq we can't rely on tw ordering guarantees, defer
+ * flushing notif to io_send_zc_cleanup()
+ */
+ if (!(issue_flags & IO_URING_F_UNLOCKED)) {
+ io_notif_flush(sr->notif);
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ }
+ io_req_set_res(req, ret, IORING_CQE_F_MORE);
+ return IOU_OK;
+}
+
+void io_sendrecv_fail(struct io_kiocb *req)
+{
+ struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
+
+ if (req->flags & REQ_F_PARTIAL_IO)
+ req->cqe.res = sr->done_io;
+
+ if ((req->flags & REQ_F_NEED_CLEANUP) &&
+ (req->opcode == IORING_OP_SEND_ZC || req->opcode == IORING_OP_SENDMSG_ZC))
+ req->cqe.flags |= IORING_CQE_F_MORE;
+}
+