infiniband: remove dev_base_lock use

dev_base_lock is the legacy way to lock the device list, and is planned
to disappear. (writers hold RTNL, readers hold RCU lock)

Convert rdma_translate_ip() and update_ipv6_gids() to RCU locking.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/infiniband/core/addr.c

@@ -130,8 +130,8 @@ int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 	case AF_INET6:
-		read_lock(&dev_base_lock);
-		for_each_netdev(&init_net, dev) {
+		rcu_read_lock();
+		for_each_netdev_rcu(&init_net, dev) {
 			if (ipv6_chk_addr(&init_net,
 					  &((struct sockaddr_in6 *) addr)->sin6_addr,
 					  dev, 1)) {
@@ -139,7 +139,7 @@ int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
 				break;
 			}
 		}
-		read_unlock(&dev_base_lock);
+		rcu_read_unlock();
 		break;
 #endif
 	}

drivers/infiniband/hw/mlx4/main.c

@@ -848,8 +848,8 @@ static int update_ipv6_gids(struct mlx4_ib_dev *dev, int port, int clear)
 		goto out;
 	}
 
-	read_lock(&dev_base_lock);
-	for_each_netdev(&init_net, tmp) {
+	rcu_read_lock();
+	for_each_netdev_rcu(&init_net, tmp) {
 		if (ndev && (tmp == ndev || rdma_vlan_dev_real_dev(tmp) == ndev)) {
 			gid.global.subnet_prefix = cpu_to_be64(0xfe80000000000000LL);
 			vid = rdma_vlan_dev_vlan_id(tmp);
@@ -884,7 +884,7 @@ static int update_ipv6_gids(struct mlx4_ib_dev *dev, int port, int clear)
 			}
 		}
 	}
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
 
 	for (i = 0; i < 128; ++i)
 		if (!hits[i]) {