From: Sagi Grimberg <sagi@grimberg.me>
Date: Mon, 18 May 2020 10:47:48 -0700
Subject: [PATCH] nvmet-tcp: move send/recv error handling in the send/recv
 methods instead of call-sites
Git-commit: 0236d3437909ff888e5c79228e2d5a851651c4c6
Patch-mainline: v5.8-rc1
References: jsc#SLE-15608

Have routines handle errors and just bail out of the poll loop.
This simplifies the code and will help as we may enhance the poll
loop logic and these are somewhat in the way.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/nvme/target/tcp.c | 43 ++++++++++++++++++++++++-------------------
 1 file changed, 24 insertions(+), 19 deletions(-)

diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index f8dd69f3b657..6f557db0320d 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -325,6 +325,14 @@ static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue)
 		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
 }
 
+static void nvmet_tcp_socket_error(struct nvmet_tcp_queue *queue, int status)
+{
+	if (status == -EPIPE || status == -ECONNRESET)
+		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
+	else
+		nvmet_tcp_fatal_error(queue);
+}
+
 static int nvmet_tcp_map_data(struct nvmet_tcp_cmd *cmd)
 {
 	struct nvme_sgl_desc *sgl = &cmd->req.cmd->common.dptr.sgl;
@@ -718,11 +726,15 @@ static int nvmet_tcp_try_send(struct nvmet_tcp_queue *queue,
 
 	for (i = 0; i < budget; i++) {
 		ret = nvmet_tcp_try_send_one(queue, i == budget - 1);
-		if (ret <= 0)
+		if (unlikely(ret < 0)) {
+			nvmet_tcp_socket_error(queue, ret);
+			goto done;
+		} else if (ret == 0) {
 			break;
+		}
 		(*sends)++;
 	}
-
+done:
 	return ret;
 }
 
@@ -1159,11 +1171,15 @@ static int nvmet_tcp_try_recv(struct nvmet_tcp_queue *queue,
 
 	for (i = 0; i < budget; i++) {
 		ret = nvmet_tcp_try_recv_one(queue);
-		if (ret <= 0)
+		if (unlikely(ret < 0)) {
+			nvmet_tcp_socket_error(queue, ret);
+			goto done;
+		} else if (ret == 0) {
 			break;
+		}
 		(*recvs)++;
 	}
-
+done:
 	return ret;
 }
 
@@ -1188,27 +1204,16 @@ static void nvmet_tcp_io_work(struct work_struct *w)
 		pending = false;
 
 		ret = nvmet_tcp_try_recv(queue, NVMET_TCP_RECV_BUDGET, &ops);
-		if (ret > 0) {
+		if (ret > 0)
 			pending = true;
-		} else if (ret < 0) {
-			if (ret == -EPIPE || ret == -ECONNRESET)
-				kernel_sock_shutdown(queue->sock, SHUT_RDWR);
-			else
-				nvmet_tcp_fatal_error(queue);
+		else if (ret < 0)
 			return;
-		}
 
 		ret = nvmet_tcp_try_send(queue, NVMET_TCP_SEND_BUDGET, &ops);
-		if (ret > 0) {
-			/* transmitted message/data */
+		if (ret > 0)
 			pending = true;
-		} else if (ret < 0) {
-			if (ret == -EPIPE || ret == -ECONNRESET)
-				kernel_sock_shutdown(queue->sock, SHUT_RDWR);
-			else
-				nvmet_tcp_fatal_error(queue);
+		else if (ret < 0)
 			return;
-		}
 
 	} while (pending && ops < NVMET_TCP_IO_WORK_BUDGET);
 
-- 
2.16.4