mac802154: add ifname change notifier

This patch adds a netdev notifier for interface renaming. We have a name
attribute inside of subif data struct. This is needed to have always the
actual netdev name in sdata name attribute.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

net/mac802154/ieee802154_i.h

@@ -169,6 +169,9 @@ void mac802154_get_table(struct net_device *dev,
 			 struct ieee802154_llsec_table **t);
 void mac802154_unlock_table(struct net_device *dev);
 
+/* interface handling */
+int ieee802154_iface_init(void);
+void ieee802154_iface_exit(void);
 struct net_device *
 mac802154_add_iface(struct wpan_phy *phy, const char *name, int type);
 void ieee802154_if_remove(struct ieee802154_sub_if_data *sdata);

net/mac802154/iface.c

@@ -548,3 +548,38 @@ void ieee802154_remove_interfaces(struct ieee802154_local *local)
 	}
 	mutex_unlock(&local->iflist_mtx);
 }
+
+static int netdev_notify(struct notifier_block *nb,
+			 unsigned long state, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct ieee802154_sub_if_data *sdata;
+
+	if (state != NETDEV_CHANGENAME)
+		return NOTIFY_DONE;
+
+	if (!dev->ieee802154_ptr || !dev->ieee802154_ptr->wpan_phy)
+		return NOTIFY_DONE;
+
+	if (dev->ieee802154_ptr->wpan_phy->privid != mac802154_wpan_phy_privid)
+		return NOTIFY_DONE;
+
+	sdata = IEEE802154_DEV_TO_SUB_IF(dev);
+	memcpy(sdata->name, dev->name, IFNAMSIZ);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block mac802154_netdev_notifier = {
+	.notifier_call = netdev_notify,
+};
+
+int ieee802154_iface_init(void)
+{
+	return register_netdevice_notifier(&mac802154_netdev_notifier);
+}
+
+void ieee802154_iface_exit(void)
+{
+	unregister_netdevice_notifier(&mac802154_netdev_notifier);
+}

net/mac802154/main.c

@@ -182,5 +182,20 @@ void ieee802154_unregister_hw(struct ieee802154_hw *hw)
 }
 EXPORT_SYMBOL(ieee802154_unregister_hw);
 
+static int __init ieee802154_init(void)
+{
+	return ieee802154_iface_init();
+}
+
+static void __exit ieee802154_exit(void)
+{
+	ieee802154_iface_exit();
+
+	rcu_barrier();
+}
+
+subsys_initcall(ieee802154_init);
+module_exit(ieee802154_exit);
+
 MODULE_DESCRIPTION("IEEE 802.15.4 subsystem");
 MODULE_LICENSE("GPL v2");