macvlan: advertise link netns via netlink

Assign rtnl_link_ops->get_link_net() callback so that IFLA_LINK_NETNSID is
added to rtnetlink messages.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 612e073..1df38bd 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1471,11 +1471,17 @@
 };
 EXPORT_SYMBOL_GPL(macvlan_link_register);
 
+static struct net *macvlan_get_link_net(const struct net_device *dev)
+{
+	return dev_net(macvlan_dev_real_dev(dev));
+}
+
 static struct rtnl_link_ops macvlan_link_ops = {
 	.kind		= "macvlan",
 	.setup		= macvlan_setup,
 	.newlink	= macvlan_newlink,
 	.dellink	= macvlan_dellink,
+	.get_link_net	= macvlan_get_link_net,
 };
 
 static int macvlan_device_event(struct notifier_block *unused,