io_uring/net: extract io_send_select_buffer()

Extract a helper out of io_send() for provided buffer selection to
improve readability as it has grown to take too many lines.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/26a769cdabd61af7f40c5d88a22469c5ad071796.1738087204.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: isilence

io_uring/net.c

@@ -566,6 +566,54 @@ int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
 	return IOU_OK;
 }
 
+static int io_send_select_buffer(struct io_kiocb *req, unsigned int issue_flags,
+				 struct io_async_msghdr *kmsg)
+{
+	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
+
+	int ret;
+	struct buf_sel_arg arg = {
+		.iovs = &kmsg->fast_iov,
+		.max_len = min_not_zero(sr->len, INT_MAX),
+		.nr_iovs = 1,
+	};
+
+	if (kmsg->free_iov) {
+		arg.nr_iovs = kmsg->free_iov_nr;
+		arg.iovs = kmsg->free_iov;
+		arg.mode = KBUF_MODE_FREE;
+	}
+
+	if (!(sr->flags & IORING_RECVSEND_BUNDLE))
+		arg.nr_iovs = 1;
+	else
+		arg.mode |= KBUF_MODE_EXPAND;
+
+	ret = io_buffers_select(req, &arg, issue_flags);
+	if (unlikely(ret < 0))
+		return ret;
+
+	if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) {
+		kmsg->free_iov_nr = ret;
+		kmsg->free_iov = arg.iovs;
+		req->flags |= REQ_F_NEED_CLEANUP;
+	}
+	sr->len = arg.out_len;
+
+	if (ret == 1) {
+		sr->buf = arg.iovs[0].iov_base;
+		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
+					&kmsg->msg.msg_iter);
+		if (unlikely(ret))
+			return ret;
+	} else {
+		iov_iter_init(&kmsg->msg.msg_iter, ITER_SOURCE,
+				arg.iovs, ret, arg.out_len);
+	}
+
+	return 0;
+}
+
 int io_send(struct io_kiocb *req, unsigned int issue_flags)
 {
 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
@@ -589,44 +637,9 @@ int io_send(struct io_kiocb *req, unsigned int issue_flags)
 
 retry_bundle:
 	if (io_do_buffer_select(req)) {
-		struct buf_sel_arg arg = {
-			.iovs = &kmsg->fast_iov,
-			.max_len = min_not_zero(sr->len, INT_MAX),
-			.nr_iovs = 1,
-		};
-
-		if (kmsg->free_iov) {
-			arg.nr_iovs = kmsg->free_iov_nr;
-			arg.iovs = kmsg->free_iov;
-			arg.mode = KBUF_MODE_FREE;
-		}
-
-		if (!(sr->flags & IORING_RECVSEND_BUNDLE))
-			arg.nr_iovs = 1;
-		else
-			arg.mode |= KBUF_MODE_EXPAND;
-
-		ret = io_buffers_select(req, &arg, issue_flags);
-		if (unlikely(ret < 0))
+		ret = io_send_select_buffer(req, issue_flags, kmsg);
+		if (ret)
 			return ret;
-
-		if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) {
-			kmsg->free_iov_nr = ret;
-			kmsg->free_iov = arg.iovs;
-			req->flags |= REQ_F_NEED_CLEANUP;
-		}
-		sr->len = arg.out_len;
-
-		if (ret == 1) {
-			sr->buf = arg.iovs[0].iov_base;
-			ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
-						&kmsg->msg.msg_iter);
-			if (unlikely(ret))
-				return ret;
-		} else {
-			iov_iter_init(&kmsg->msg.msg_iter, ITER_SOURCE,
-					arg.iovs, ret, arg.out_len);
-		}
 	}
 
 	/*