6lowpan: add lowpan dev register helpers

This patch introduces register and unregister functionality for lowpan
interfaces. While register a lowpan interface there are several things
which need to be initialize by the 6lowpan subsystem. Upcoming
functionality need to register/unregister per interface components e.g.
debugfs entry.
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

include/net/6lowpan.h

@@ -185,7 +185,12 @@ static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data,
 	*hc_ptr += len;
 }
 
-void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype);
+int lowpan_register_netdevice(struct net_device *dev,
+			      enum lowpan_lltypes lltype);
+int lowpan_register_netdev(struct net_device *dev,
+			   enum lowpan_lltypes lltype);
+void lowpan_unregister_netdevice(struct net_device *dev);
+void lowpan_unregister_netdev(struct net_device *dev);
 
 /**
  * lowpan_header_decompress - replace 6LoWPAN header with IPv6 header

net/6lowpan/core.c

@@ -15,7 +15,8 @@
 
 #include <net/6lowpan.h>
 
-void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype)
+int lowpan_register_netdevice(struct net_device *dev,
+			      enum lowpan_lltypes lltype)
 {
 	dev->addr_len = EUI64_ADDR_LEN;
 	dev->type = ARPHRD_6LOWPAN;
@@ -23,8 +24,36 @@ void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype)
 	dev->priv_flags |= IFF_NO_QUEUE;
 
 	lowpan_priv(dev)->lltype = lltype;
+
+	return register_netdevice(dev);
+}
+EXPORT_SYMBOL(lowpan_register_netdevice);
+
+int lowpan_register_netdev(struct net_device *dev,
+			   enum lowpan_lltypes lltype)
+{
+	int ret;
+
+	rtnl_lock();
+	ret = lowpan_register_netdevice(dev, lltype);
+	rtnl_unlock();
+	return ret;
+}
+EXPORT_SYMBOL(lowpan_register_netdev);
+
+void lowpan_unregister_netdevice(struct net_device *dev)
+{
+	unregister_netdevice(dev);
+}
+EXPORT_SYMBOL(lowpan_unregister_netdevice);
+
+void lowpan_unregister_netdev(struct net_device *dev)
+{
+	rtnl_lock();
+	lowpan_unregister_netdevice(dev);
+	rtnl_unlock();
 }
-EXPORT_SYMBOL(lowpan_netdev_setup);
+EXPORT_SYMBOL(lowpan_unregister_netdev);
 
 static int __init lowpan_module_init(void)
 {

net/bluetooth/6lowpan.c

@@ -825,9 +825,7 @@ static int setup_netdev(struct l2cap_chan *chan, struct lowpan_dev **dev)
 	list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
 	spin_unlock(&devices_lock);
 
-	lowpan_netdev_setup(netdev, LOWPAN_LLTYPE_BTLE);
-
-	err = register_netdev(netdev);
+	err = lowpan_register_netdev(netdev, LOWPAN_LLTYPE_BTLE);
 	if (err < 0) {
 		BT_INFO("register_netdev failed %d", err);
 		spin_lock(&devices_lock);
@@ -890,7 +888,7 @@ static void delete_netdev(struct work_struct *work)
 	struct lowpan_dev *entry = container_of(work, struct lowpan_dev,
 						delete_netdev);
 
-	unregister_netdev(entry->netdev);
+	lowpan_unregister_netdev(entry->netdev);
 
 	/* The entry pointer is deleted by the netdev destructor. */
 }
@@ -1348,7 +1346,7 @@ static void disconnect_devices(void)
 		ifdown(entry->netdev);
 		BT_DBG("Unregistering netdev %s %p",
 		       entry->netdev->name, entry->netdev);
-		unregister_netdev(entry->netdev);
+		lowpan_unregister_netdev(entry->netdev);
 		kfree(entry);
 	}
 }

net/ieee802154/6lowpan/core.c

@@ -161,9 +161,7 @@ static int lowpan_newlink(struct net *src_net, struct net_device *ldev,
 				wdev->needed_headroom;
 	ldev->needed_tailroom = wdev->needed_tailroom;
 
-	lowpan_netdev_setup(ldev, LOWPAN_LLTYPE_IEEE802154);
-
-	ret = register_netdevice(ldev);
+	ret = lowpan_register_netdevice(ldev, LOWPAN_LLTYPE_IEEE802154);
 	if (ret < 0) {
 		dev_put(wdev);
 		return ret;
@@ -180,7 +178,7 @@ static void lowpan_dellink(struct net_device *ldev, struct list_head *head)
 	ASSERT_RTNL();
 
 	wdev->ieee802154_ptr->lowpan_dev = NULL;
-	unregister_netdevice(ldev);
+	lowpan_unregister_netdevice(ldev);
 	dev_put(wdev);
 }