[PATCH 08/17] nvme-tcp: fixup MSG_SENDPAGE_NOTLAST

[Hannes Reinecke]

We can only set MSG_SENDPAGE_NOTLAST when sending the command PDU if the
actual data is transferred via sendpage(), too.
If we use sendmsg() to transfer the data we end up with a TX stall on TLS
as it implements different code paths for sendmsg() and sendpage().
So check in nvme_tcp_try_send_pdu() if inline data is present and revert
to sendmsg if the inline data cannot be sent via sendpage().

Signed-off-by: Hannes Reinecke <hare at suse.de>
---
 drivers/nvme/host/tcp.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 273c1f2760a4..9ecd7db2cd98 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -995,9 +995,11 @@ static int nvme_tcp_try_send_data(struct nvme_tcp_request *req)
 		if (last && !queue->data_digest && !nvme_tcp_queue_more(queue))
 			flags |= MSG_EOR;
 		else
-			flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
+			flags |= MSG_MORE;
 
 		if (sendpage_ok(page)) {
+			if (flags & MSG_MORE)
+				flags |= MSG_SENDPAGE_NOTLAST;
 			ret = kernel_sendpage(queue->sock, page, offset, len,
 					flags);
 		} else {
@@ -1049,15 +1051,23 @@ static int nvme_tcp_try_send_cmd_pdu(struct nvme_tcp_request *req)
 	int ret;
 
 	if (inline_data || nvme_tcp_queue_more(queue))
-		flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
+		flags |= MSG_MORE;
 	else
 		flags |= MSG_EOR;
 
 	if (queue->hdr_digest && !req->offset)
 		nvme_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu));
 
-	ret = kernel_sendpage(queue->sock, virt_to_page(pdu),
-			offset_in_page(pdu) + req->offset, len,  flags);
+	if (!inline_data || sendpage_ok(nvme_tcp_req_cur_page(req))) {
+		if (flags & MSG_MORE)
+			flags |= MSG_SENDPAGE_NOTLAST;
+		ret = kernel_sendpage(queue->sock, virt_to_page(pdu),
+				offset_in_page(pdu) + req->offset, len,  flags);
+	} else {
+		ret = sock_no_sendpage(queue->sock, virt_to_page(pdu),
+				offset_in_page(pdu) + req->offset,
+				len, flags);
+	}
 	if (unlikely(ret <= 0))
 		return ret;
 
-- 
2.35.3