Merge tag 'for-6.5/io_uring-2023-06-23' of git://git.kernel.dk/linux

Pull io_uring updates from Jens Axboe:
 "Nothing major in this release, just a bunch of cleanups and some
  optimizations around networking mostly.

   - clean up file request flags handling (Christoph)

   - clean up request freeing and CQ locking (Pavel)

   - support for using pre-registering the io_uring fd at setup time
     (Josh)

   - Add support for user allocated ring memory, rather than having the
     kernel allocate it. Mostly for packing rings into a huge page (me)

   - avoid an unnecessary double retry on receive (me)

   - maintain ordering for task_work, which also improves performance
     (me)

   - misc cleanups/fixes (Pavel, me)"

* tag 'for-6.5/io_uring-2023-06-23' of git://git.kernel.dk/linux: (39 commits)
  io_uring: merge conditional unlock flush helpers
  io_uring: make io_cq_unlock_post static
  io_uring: inline __io_cq_unlock
  io_uring: fix acquire/release annotations
  io_uring: kill io_cq_unlock()
  io_uring: remove IOU_F_TWQ_FORCE_NORMAL
  io_uring: don't batch task put on reqs free
  io_uring: move io_clean_op()
  io_uring: inline io_dismantle_req()
  io_uring: remove io_free_req_tw
  io_uring: open code io_put_req_find_next
  io_uring: add helpers to decode the fixed file file_ptr
  io_uring: use io_file_from_index in io_msg_grab_file
  io_uring: use io_file_from_index in __io_sync_cancel
  io_uring: return REQ_F_ flags from io_file_get_flags
  io_uring: remove io_req_ffs_set
  io_uring: remove a confusing comment above io_file_get_flags
  io_uring: remove the mode variable in io_file_get_flags
  io_uring: remove __io_file_supports_nowait
  io_uring: wait interruptibly for request completions on exit
  ...

1 files changed, 32 insertions, 26 deletions

diff --git a/io_uring/net.c b/io_uring/net.c
index c8a4b2ac00f7..a8e303796f16 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -624,9 +624,15 @@ static inline void io_recv_prep_retry(struct io_kiocb *req)
  * again (for multishot).
  */
 static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
-				  unsigned int cflags, bool mshot_finished,
+				  struct msghdr *msg, bool mshot_finished,
 				  unsigned issue_flags)
 {
+	unsigned int cflags;
+
+	cflags = io_put_kbuf(req, issue_flags);
+	if (msg->msg_inq && msg->msg_inq != -1U)
+		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
+
 	if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
 		io_req_set_res(req, *ret, cflags);
 		*ret = IOU_OK;
@@ -634,10 +640,18 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
 	}
 
 	if (!mshot_finished) {
-		if (io_aux_cqe(req->ctx, issue_flags & IO_URING_F_COMPLETE_DEFER,
-			       req->cqe.user_data, *ret, cflags | IORING_CQE_F_MORE, true)) {
+		if (io_aux_cqe(req, issue_flags & IO_URING_F_COMPLETE_DEFER,
+			       *ret, cflags | IORING_CQE_F_MORE, true)) {
 			io_recv_prep_retry(req);
-			return false;
+			/* Known not-empty or unknown state, retry */
+			if (cflags & IORING_CQE_F_SOCK_NONEMPTY ||
+			    msg->msg_inq == -1U)
+				return false;
+			if (issue_flags & IO_URING_F_MULTISHOT)
+				*ret = IOU_ISSUE_SKIP_COMPLETE;
+			else
+				*ret = -EAGAIN;
+			return true;
 		}
 		/* Otherwise stop multishot but use the current result. */
 	}
@@ -740,7 +754,6 @@ int io_recvmsg(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 ret, min_ret = 0;
 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
@@ -791,6 +804,7 @@ retry_multishot:
 		flags |= MSG_DONTWAIT;
 
 	kmsg->msg.msg_get_inq = 1;
+	kmsg->msg.msg_inq = -1U;
 	if (req->flags & REQ_F_APOLL_MULTISHOT) {
 		ret = io_recvmsg_multishot(sock, sr, kmsg, flags,
 					   &mshot_finished);
@@ -831,11 +845,7 @@ retry_multishot:
 	else
 		io_kbuf_recycle(req, issue_flags);
 
-	cflags = io_put_kbuf(req, issue_flags);
-	if (kmsg->msg.msg_inq)
-		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
-
-	if (!io_recv_finish(req, &ret, cflags, mshot_finished, issue_flags))
+	if (!io_recv_finish(req, &ret, &kmsg->msg, mshot_finished, issue_flags))
 		goto retry_multishot;
 
 	if (mshot_finished) {
@@ -854,7 +864,6 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags)
 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
 	struct msghdr msg;
 	struct socket *sock;
-	unsigned int cflags;
 	unsigned flags;
 	int ret, min_ret = 0;
 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
@@ -871,6 +880,14 @@ int io_recv(struct io_kiocb *req, unsigned int issue_flags)
 	if (unlikely(!sock))
 		return -ENOTSOCK;
 
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_control = NULL;
+	msg.msg_get_inq = 1;
+	msg.msg_controllen = 0;
+	msg.msg_iocb = NULL;
+	msg.msg_ubuf = NULL;
+
 retry_multishot:
 	if (io_do_buffer_select(req)) {
 		void __user *buf;
@@ -885,14 +902,8 @@ retry_multishot:
 	if (unlikely(ret))
 		goto out_free;
 
-	msg.msg_name = NULL;
-	msg.msg_namelen = 0;
-	msg.msg_control = NULL;
-	msg.msg_get_inq = 1;
+	msg.msg_inq = -1U;
 	msg.msg_flags = 0;
-	msg.msg_controllen = 0;
-	msg.msg_iocb = NULL;
-	msg.msg_ubuf = NULL;
 
 	flags = sr->msg_flags;
 	if (force_nonblock)
@@ -932,11 +943,7 @@ out_free:
 	else
 		io_kbuf_recycle(req, issue_flags);
 
-	cflags = io_put_kbuf(req, issue_flags);
-	if (msg.msg_inq)
-		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
-
-	if (!io_recv_finish(req, &ret, cflags, ret <= 0, issue_flags))
+	if (!io_recv_finish(req, &ret, &msg, ret <= 0, issue_flags))
 		goto retry_multishot;
 
 	return ret;
@@ -1308,7 +1315,6 @@ int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 
 int io_accept(struct io_kiocb *req, unsigned int issue_flags)
 {
-	struct io_ring_ctx *ctx = req->ctx;
 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
 	unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
@@ -1358,8 +1364,8 @@ retry:
 
 	if (ret < 0)
 		return ret;
-	if (io_aux_cqe(ctx, issue_flags & IO_URING_F_COMPLETE_DEFER,
-		       req->cqe.user_data, ret, IORING_CQE_F_MORE, true))
+	if (io_aux_cqe(req, issue_flags & IO_URING_F_COMPLETE_DEFER, ret,
+		       IORING_CQE_F_MORE, true))
 		goto retry;
 
 	return -ECANCELED;