[PATCH 2/2] nvmet-tcp: add keep-alive

[zhenwei pi]

Add tcp keep-alive to detect dead connections for zero KATO case.

Signed-off-by: zhenwei pi <pizhenwei at bytedance.com>
---
 drivers/nvme/target/tcp.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index dc1f0f647189..58800e914e61 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -1714,6 +1714,30 @@ static void nvmet_tcp_disc_port_addr(struct nvmet_req *req,
 	}
 }
 
+static int nvmet_tcp_keep_alive(struct nvmet_req *req)
+{
+	struct nvmet_tcp_cmd *cmd = container_of(req, struct nvmet_tcp_cmd, req);
+	struct nvmet_tcp_queue *queue = cmd->queue;
+	struct socket *sock = queue->sock;
+	int ret;
+
+	/* TCP Keepalive options, max 5+1*3 = 8s */
+	sock_set_keepalive(sock->sk);
+	ret = tcp_sock_set_keepidle(sock->sk, 5);
+	if (ret)
+		return ret;
+
+	ret = tcp_sock_set_keepintvl(sock->sk, 1);
+	if (ret)
+		return ret;
+
+	ret = tcp_sock_set_keepcnt(sock->sk, 3);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 static const struct nvmet_fabrics_ops nvmet_tcp_ops = {
 	.owner			= THIS_MODULE,
 	.type			= NVMF_TRTYPE_TCP,
@@ -1724,6 +1748,7 @@ static const struct nvmet_fabrics_ops nvmet_tcp_ops = {
 	.delete_ctrl		= nvmet_tcp_delete_ctrl,
 	.install_queue		= nvmet_tcp_install_queue,
 	.disc_traddr		= nvmet_tcp_disc_port_addr,
+	.keep_alive		= nvmet_tcp_keep_alive,
 };
 
 static int __init nvmet_tcp_init(void)
-- 
2.11.0