[PATCH v3 3/4] nvmet-tcp: support IPv6 traffic class

[Geliang Tang]

From: Geliang Tang <tanggeliang at kylinos.cn>

Currently, nvmet-tcp only applies the received IPv4 TOS value when setting
up a queue socket, but does not handle the IPv6 traffic class.

Extend the queue socket setup to handle AF_INET6 sockets. Obtain the
traffic class from the IPv6 socket's rcv_flowinfo and apply it through
IPV6_TCLASS using do_sock_setsockopt().

Signed-off-by: Geliang Tang <tanggeliang at kylinos.cn>
---
 drivers/nvme/target/tcp.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index e64592b79257..d34249cf3756 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -1735,6 +1735,20 @@ static void nvmet_tcp_sock_set_tos(struct sock *sk)
 				   KERNEL_SOCKPTR(&tos), sizeof(tos));
 }
 
+static void nvmet_tcp_sock_set_tclass(struct sock *sk)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	if (sk->sk_family == AF_INET6) {
+		u8 tclass = ip6_tclass(inet6_sk(sk)->rcv_flowinfo);
+
+		if (tclass > 0)
+			do_sock_setsockopt(sk->sk_socket, false, SOL_IPV6,
+					   IPV6_TCLASS, KERNEL_SOCKPTR(&tclass),
+					   sizeof(tclass));
+	}
+#endif
+}
+
 static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue)
 {
 	struct socket *sock = queue->sock;
@@ -1762,6 +1776,7 @@ static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue)
 
 	/* Set socket type of service */
 	nvmet_tcp_sock_set_tos(sock->sk);
+	nvmet_tcp_sock_set_tclass(sock->sk);
 
 	ret = 0;
 	write_lock_bh(&sock->sk->sk_callback_lock);
-- 
2.53.0