[RTNL]: Introduce the rtnl_kill_links helper.

This one is responsible for calling ->dellink on each net
device found in net to help with vlan net_exit hook in the
nearest future.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 22 insertions, 8 deletions

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 793863e09c69..3c1895e54b7f 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -74,6 +74,7 @@ struct rtnl_link_ops {
 
 extern int      __rtnl_link_register(struct rtnl_link_ops *ops);
 extern void     __rtnl_link_unregister(struct rtnl_link_ops *ops);
+extern void     rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops);
 
 extern int      rtnl_link_register(struct rtnl_link_ops *ops);
 extern void     rtnl_link_unregister(struct rtnl_link_ops *ops);
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index edc6dbfe48f2..bc39e417694a 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -269,6 +269,26 @@ int rtnl_link_register(struct rtnl_link_ops *ops)
 
 EXPORT_SYMBOL_GPL(rtnl_link_register);
 
+static void __rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
+{
+        struct net_device *dev;
+restart:
+        for_each_netdev(net, dev) {
+                if (dev->rtnl_link_ops == ops) {
+                        ops->dellink(dev);
+                        goto restart;
+                }
+        }
+}
+
+void rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
+{
+        rtnl_lock();
+        __rtnl_kill_links(net, ops);
+        rtnl_unlock();
+}
+EXPORT_SYMBOL_GPL(rtnl_kill_links);
+
 /**
  * __rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.
  * @ops: struct rtnl_link_ops * to unregister
@@ -277,17 +297,10 @@ EXPORT_SYMBOL_GPL(rtnl_link_register);
  */
 void __rtnl_link_unregister(struct rtnl_link_ops *ops)
 {
-        struct net_device *dev;
         struct net *net;
 
         for_each_net(net) {
-restart:
-                for_each_netdev(net, dev) {
-                        if (dev->rtnl_link_ops == ops) {
-                                ops->dellink(dev);
-                                goto restart;
-                        }
-                }
+                __rtnl_kill_links(net, ops);
         }
         list_del(&ops->list);
 }