net: push loops and nb calls into helper functions

Push iterations over net namespaces and netdevices from
register_netdevice_notifier() and unregister_netdevice_notifier()
into helper functions. Along with that introduce continue_reverse macros
to make the code a bit nicer allowing to get rid of "last" marks.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 61 insertions, 28 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 7a456c6a7ad8..a8b70cb6c732 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1725,6 +1725,62 @@ static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
 	return nb->notifier_call(nb, val, &info);
 }
 
+static int call_netdevice_register_notifiers(struct notifier_block *nb,
+					     struct net_device *dev)
+{
+	int err;
+
+	err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
+	err = notifier_to_errno(err);
+	if (err)
+		return err;
+
+	if (!(dev->flags & IFF_UP))
+		return 0;
+
+	call_netdevice_notifier(nb, NETDEV_UP, dev);
+	return 0;
+}
+
+static void call_netdevice_unregister_notifiers(struct notifier_block *nb,
+						struct net_device *dev)
+{
+	if (dev->flags & IFF_UP) {
+		call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
+					dev);
+		call_netdevice_notifier(nb, NETDEV_DOWN, dev);
+	}
+	call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
+}
+
+static int call_netdevice_register_net_notifiers(struct notifier_block *nb,
+						 struct net *net)
+{
+	struct net_device *dev;
+	int err;
+
+	for_each_netdev(net, dev) {
+		err = call_netdevice_register_notifiers(nb, dev);
+		if (err)
+			goto rollback;
+	}
+	return 0;
+
+rollback:
+	for_each_netdev_continue_reverse(net, dev)
+		call_netdevice_unregister_notifiers(nb, dev);
+	return err;
+}
+
+static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb,
+						    struct net *net)
+{
+	struct net_device *dev;
+
+	for_each_netdev(net, dev)
+		call_netdevice_unregister_notifiers(nb, dev);
+}
+
 static int dev_boot_phase = 1;
 
 /**
@@ -1743,8 +1799,6 @@ static int dev_boot_phase = 1;
 
 int register_netdevice_notifier(struct notifier_block *nb)
 {
-	struct net_device *dev;
-	struct net_device *last;
 	struct net *net;
 	int err;
 
@@ -1757,17 +1811,9 @@ int register_netdevice_notifier(struct notifier_block *nb)
 	if (dev_boot_phase)
 		goto unlock;
 	for_each_net(net) {
-		for_each_netdev(net, dev) {
-			err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
-			err = notifier_to_errno(err);
-			if (err)
-				goto rollback;
-
-			if (!(dev->flags & IFF_UP))
-				continue;
-
-			call_netdevice_notifier(nb, NETDEV_UP, dev);
-		}
+		err = call_netdevice_register_net_notifiers(nb, net);
+		if (err)
+			goto rollback;
 	}
 
 unlock:
@@ -1776,22 +1822,9 @@ unlock:
 	return err;
 
 rollback:
-	last = dev;
-	for_each_net(net) {
-		for_each_netdev(net, dev) {
-			if (dev == last)
-				goto outroll;
-
-			if (dev->flags & IFF_UP) {
-				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
-							dev);
-				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
-			}
-			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
-		}
-	}
+	for_each_net_continue_reverse(net)
+		call_netdevice_unregister_net_notifiers(nb, net);
 
-outroll:
 	raw_notifier_chain_unregister(&netdev_chain, nb);
 	goto unlock;
 }