From 7297ce3d59449de49d3c9e1f64ae25488750a1fc Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@gmail.com>
Date: Tue, 23 Nov 2021 00:07:47 +0000
Subject: [PATCH] io_uring: improve send/recv error handling
Git-commit: 7297ce3d59449de49d3c9e1f64ae25488750a1fc
Patch-mainline: v5.17-rc1
References: bsc#1205205

Hide all error handling under common if block, removes two extra ifs on
the success path and keeps the handling more condensed.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5761545158a12968f3caf30f747eea65ed75dfc1.1637524285.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
---
 fs/io_uring.c | 55 +++++++++++++++++++++++++++++----------------------
 1 file changed, 31 insertions(+), 24 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 8b7b30835c72..7ef2d0c1296f 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -4788,17 +4788,18 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
 
 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
-	if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
-		return io_setup_async_msg(req, kmsg);
-	if (ret == -ERESTARTSYS)
-		ret = -EINTR;
 
+	if (ret < min_ret) {
+		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
+			return io_setup_async_msg(req, kmsg);
+		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);
 	req->flags &= ~REQ_F_NEED_CLEANUP;
-	if (ret < min_ret)
-		req_set_fail(req);
 	__io_req_complete(req, issue_flags, ret, 0);
 	return 0;
 }
@@ -4834,13 +4835,13 @@ static int io_send(struct io_kiocb *req, unsigned int issue_flags)
 
 	msg.msg_flags = flags;
 	ret = sock_sendmsg(sock, &msg);
-	if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
-		return -EAGAIN;
-	if (ret == -ERESTARTSYS)
-		ret = -EINTR;
-
-	if (ret < min_ret)
+	if (ret < min_ret) {
+		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
+			return -EAGAIN;
+		if (ret == -ERESTARTSYS)
+			ret = -EINTR;
 		req_set_fail(req);
+	}
 	__io_req_complete(req, issue_flags, ret, 0);
 	return 0;
 }
@@ -5017,10 +5018,15 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
 
 	ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
 					kmsg->uaddr, flags);
-	if (force_nonblock && ret == -EAGAIN)
-		return io_setup_async_msg(req, kmsg);
-	if (ret == -ERESTARTSYS)
-		ret = -EINTR;
+	if (ret < min_ret) {
+		if (ret == -EAGAIN && force_nonblock)
+			return io_setup_async_msg(req, kmsg);
+		if (ret == -ERESTARTSYS)
+			ret = -EINTR;
+		req_set_fail(req);
+	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
+		req_set_fail(req);
+	}
 
 	if (req->flags & REQ_F_BUFFER_SELECTED)
 		cflags = io_put_recv_kbuf(req);
@@ -5028,8 +5034,6 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
 	if (kmsg->free_iov)
 		kfree(kmsg->free_iov);
 	req->flags &= ~REQ_F_NEED_CLEANUP;
-	if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
-		req_set_fail(req);
 	__io_req_complete(req, issue_flags, ret, cflags);
 	return 0;
 }
@@ -5076,15 +5080,18 @@ static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
 		min_ret = iov_iter_count(&msg.msg_iter);
 
 	ret = sock_recvmsg(sock, &msg, flags);
-	if (force_nonblock && ret == -EAGAIN)
-		return -EAGAIN;
-	if (ret == -ERESTARTSYS)
-		ret = -EINTR;
 out_free:
+	if (ret < min_ret) {
+		if (ret == -EAGAIN && force_nonblock)
+			return -EAGAIN;
+		if (ret == -ERESTARTSYS)
+			ret = -EINTR;
+		req_set_fail(req);
+	} else if ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
+		req_set_fail(req);
+	}
 	if (req->flags & REQ_F_BUFFER_SELECTED)
 		cflags = io_put_recv_kbuf(req);
-	if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
-		req_set_fail(req);
 	__io_req_complete(req, issue_flags, ret, cflags);
 	return 0;
 }
-- 
2.35.3