net: introduce default neigh_construct/destroy ndo calls for L2 upper devices

L2 upper device needs to propagate neigh_construct/destroy calls down to
lower devices. Do this by defining default ndo functions and use them in
team, bond, bridge and vlan.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev.c b/net/core/dev.c
index a4f3b0a..b92d63b 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6087,6 +6087,50 @@
 }
 EXPORT_SYMBOL(netdev_lower_state_changed);
 
+int netdev_default_l2upper_neigh_construct(struct net_device *dev,
+					   struct neighbour *n)
+{
+	struct net_device *lower_dev, *stop_dev;
+	struct list_head *iter;
+	int err;
+
+	netdev_for_each_lower_dev(dev, lower_dev, iter) {
+		if (!lower_dev->netdev_ops->ndo_neigh_construct)
+			continue;
+		err = lower_dev->netdev_ops->ndo_neigh_construct(lower_dev, n);
+		if (err) {
+			stop_dev = lower_dev;
+			goto rollback;
+		}
+	}
+	return 0;
+
+rollback:
+	netdev_for_each_lower_dev(dev, lower_dev, iter) {
+		if (lower_dev == stop_dev)
+			break;
+		if (!lower_dev->netdev_ops->ndo_neigh_destroy)
+			continue;
+		lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n);
+	}
+	return err;
+}
+EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_construct);
+
+void netdev_default_l2upper_neigh_destroy(struct net_device *dev,
+					  struct neighbour *n)
+{
+	struct net_device *lower_dev;
+	struct list_head *iter;
+
+	netdev_for_each_lower_dev(dev, lower_dev, iter) {
+		if (!lower_dev->netdev_ops->ndo_neigh_destroy)
+			continue;
+		lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n);
+	}
+}
+EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_destroy);
+
 static void dev_change_rx_flags(struct net_device *dev, int flags)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;