[PATCH 7/8] io_uring/net: support multishot for sendmsg

Jens Axboe
2024-02-25T00:39:58Z

Same as the IORING_OP_SEND multishot mode. Needs further work, but it's
functional and can be tested.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
io_uring/net.c | 33 +++++++++++++++++++++++----------
1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/io_uring/net.c b/io_uring/net.c
index 8237ac5c957f..240b8eff1a78 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -494,7 +494,6 @@ int io_sendmsg(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 int cflags;
unsigned flags;
int min_ret = 0;
int ret;
@@ -517,6 +516,10 @@ int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
(sr->flags & IORING_RECVSEND_POLL_FIRST))
return io_setup_async_msg(req, kmsg, issue_flags);

+ if (!io_check_multishot(req, issue_flags))
+ return io_setup_async_msg(req, kmsg, issue_flags);
+
+retry_multishot:
if (io_do_buffer_select(req)) {
void __user *buf;
size_t len = sr->len;
@@ -537,8 +540,14 @@ int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);

if (ret < min_ret) {
- if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
- return io_setup_async_msg(req, kmsg, issue_flags);
+ if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK)) {
+ ret = io_setup_async_msg(req, kmsg, issue_flags);
+ if (ret == -EAGAIN && (issue_flags & IO_URING_F_MULTISHOT)) {
+ io_kbuf_recycle(req, issue_flags);
+ return IOU_ISSUE_SKIP_COMPLETE;
+ }
+ return ret;
+ }
if (ret > 0 && io_net_retry(sock, flags)) {
kmsg->msg.msg_controllen = 0;
kmsg->msg.msg_control = NULL;
@@ -550,18 +559,22 @@ int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
ret = -EINTR;
req_set_fail(req);
}
+ if (ret >= 0)
+ ret += sr->done_io;
+ else if (sr->done_io)
+ ret = sr->done_io;
+ else
+ io_kbuf_recycle(req, issue_flags);
+
+ if (!io_send_finish(req, &ret, &kmsg->msg, issue_flags))
+ goto retry_multishot;
+
/* fast path, check for non-NULL to avoid function call */
if (kmsg->free_iov)
kfree(kmsg->free_iov);
req->flags &= ~REQ_F_NEED_CLEANUP;
io_netmsg_recycle(req, issue_flags);
- if (ret >= 0)
- ret += sr->done_io;
- else if (sr->done_io)
- ret = sr->done_io;
- cflags = io_put_kbuf(req, issue_flags);
- io_req_set_res(req, ret, cflags);
- return IOU_OK;
+ return ret;
}

int io_send(struct io_kiocb *req, unsigned int issue_flags)
--
2.43.0