net: add sock_set_priority

Add a helper to directly set the SO_PRIORITY sockopt from kernel space
without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index e080149..f308815 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -1448,12 +1448,8 @@ static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue)
 	 */
 	sock_no_linger(sock->sk);
 
-	if (so_priority > 0) {
-		ret = kernel_setsockopt(sock, SOL_SOCKET, SO_PRIORITY,
-				(char *)&so_priority, sizeof(so_priority));
-		if (ret)
-			return ret;
-	}
+	if (so_priority > 0)
+		sock_set_priority(sock->sk, so_priority);
 
 	/* Set socket type of service */
 	if (inet->rcv_tos > 0) {
@@ -1638,14 +1634,8 @@ static int nvmet_tcp_add_port(struct nvmet_port *nport)
 		goto err_sock;
 	}
 
-	if (so_priority > 0) {
-		ret = kernel_setsockopt(port->sock, SOL_SOCKET, SO_PRIORITY,
-				(char *)&so_priority, sizeof(so_priority));
-		if (ret) {
-			pr_err("failed to set SO_PRIORITY sock opt %d\n", ret);
-			goto err_sock;
-		}
-	}
+	if (so_priority > 0)
+		sock_set_priority(port->sock->sk, so_priority);
 
 	ret = kernel_bind(port->sock, (struct sockaddr *)&port->addr,
 			sizeof(port->addr));