net: add a list_head parameter to dellink() method

Adding a list_head parameter to rtnl_link_ops->dellink() methods
allow us to queue devices on a list, in order to dismantle
them all at once.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 52ea418..391a62c 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -248,7 +248,7 @@
 int __rtnl_link_register(struct rtnl_link_ops *ops)
 {
 	if (!ops->dellink)
-		ops->dellink = unregister_netdevice;
+		ops->dellink = unregister_netdevice_queue;
 
 	list_add_tail(&ops->list, &link_ops);
 	return 0;
@@ -277,13 +277,13 @@
 static void __rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
 {
 	struct net_device *dev;
-restart:
+	LIST_HEAD(list_kill);
+
 	for_each_netdev(net, dev) {
-		if (dev->rtnl_link_ops == ops) {
-			ops->dellink(dev);
-			goto restart;
-		}
+		if (dev->rtnl_link_ops == ops)
+			ops->dellink(dev, &list_kill);
 	}
+	unregister_netdevice_many(&list_kill);
 }
 
 void rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
@@ -972,7 +972,7 @@
 	if (!ops)
 		return -EOPNOTSUPP;
 
-	ops->dellink(dev);
+	ops->dellink(dev, NULL);
 	return 0;
 }