net/phonet/pn_dev.c - fp2-dev/kernel/msm - Gitiles

 /*
  * File: pn_dev.c
  *
  * Phonet network device
  *
  * Copyright (C) 2008 Nokia Corporation.
  *
  * Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
  * Original author: Sakari Ailus <sakari.ailus@nokia.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * version 2 as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  * 02110-1301 USA
  */

 #include <linux/kernel.h>
 #include <linux/net.h>
 #include <linux/slab.h>
 #include <linux/netdevice.h>
 #include <linux/phonet.h>
 #include <linux/proc_fs.h>
 #include <linux/if_arp.h>
 #include <net/sock.h>
 #include <net/netns/generic.h>
 #include <net/phonet/pn_dev.h>

 struct phonet_routes {
 	struct mutex		lock;
 	struct net_device	*table[64];
 };

 struct phonet_net {
 	struct phonet_device_list pndevs;
 	struct phonet_routes routes;
 };

 int phonet_net_id __read_mostly;

 static struct phonet_net *phonet_pernet(struct net *net)
 {
 	BUG_ON(!net);

 	return net_generic(net, phonet_net_id);
 }

 struct phonet_device_list *phonet_device_list(struct net *net)
 {
 	struct phonet_net *pnn = phonet_pernet(net);
 	return &pnn->pndevs;
 }

 /* Allocate new Phonet device. */
 static struct phonet_device *__phonet_device_alloc(struct net_device *dev)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
 	struct phonet_device *pnd = kmalloc(sizeof(*pnd), GFP_ATOMIC);
 	if (pnd == NULL)
 		return NULL;
 	pnd->netdev = dev;
 	bitmap_zero(pnd->addrs, 64);

 	BUG_ON(!mutex_is_locked(&pndevs->lock));
 	list_add_rcu(&pnd->list, &pndevs->list);
 	return pnd;
 }

 static struct phonet_device *__phonet_get(struct net_device *dev)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
 	struct phonet_device *pnd;

 	BUG_ON(!mutex_is_locked(&pndevs->lock));
 	list_for_each_entry(pnd, &pndevs->list, list) {
 		if (pnd->netdev == dev)
 			return pnd;
 	}
 	return NULL;
 }

 static struct phonet_device *__phonet_get_rcu(struct net_device *dev)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
 	struct phonet_device *pnd;

 	list_for_each_entry_rcu(pnd, &pndevs->list, list) {
 		if (pnd->netdev == dev)
 			return pnd;
 	}
 	return NULL;
 }

 static void phonet_device_destroy(struct net_device *dev)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
 	struct phonet_device *pnd;

 	ASSERT_RTNL();

 	mutex_lock(&pndevs->lock);
 	pnd = __phonet_get(dev);
 	if (pnd)
 		list_del_rcu(&pnd->list);
 	mutex_unlock(&pndevs->lock);

 	if (pnd) {
 		u8 addr;

 		for_each_set_bit(addr, pnd->addrs, 64)
 			phonet_address_notify(RTM_DELADDR, dev, addr);
 		kfree(pnd);
 	}
 }

 struct net_device *phonet_device_get(struct net *net)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(net);
 	struct phonet_device *pnd;
 	struct net_device *dev = NULL;

 	rcu_read_lock();
 	list_for_each_entry_rcu(pnd, &pndevs->list, list) {
 		dev = pnd->netdev;
 		BUG_ON(!dev);

 		if ((dev->reg_state == NETREG_REGISTERED) &&
 			((pnd->netdev->flags & IFF_UP)) == IFF_UP)
 			break;
 		dev = NULL;
 	}
 	if (dev)
 		dev_hold(dev);
 	rcu_read_unlock();
 	return dev;
 }

 int phonet_address_add(struct net_device *dev, u8 addr)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
 	struct phonet_device *pnd;
 	int err = 0;

 	mutex_lock(&pndevs->lock);
 	/* Find or create Phonet-specific device data */
 	pnd = __phonet_get(dev);
 	if (pnd == NULL)
 		pnd = __phonet_device_alloc(dev);
 	if (unlikely(pnd == NULL))
 		err = -ENOMEM;
 	else if (test_and_set_bit(addr >> 2, pnd->addrs))
 		err = -EEXIST;
 	mutex_unlock(&pndevs->lock);
 	return err;
 }

 static void phonet_device_rcu_free(struct rcu_head *head)
 {
 	struct phonet_device *pnd;

 	pnd = container_of(head, struct phonet_device, rcu);
 	kfree(pnd);
 }

 int phonet_address_del(struct net_device *dev, u8 addr)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
 	struct phonet_device *pnd;
 	int err = 0;

 	mutex_lock(&pndevs->lock);
 	pnd = __phonet_get(dev);
 	if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs)) {
 		err = -EADDRNOTAVAIL;
 		pnd = NULL;
 	} else if (bitmap_empty(pnd->addrs, 64))
 		list_del_rcu(&pnd->list);
 	else
 		pnd = NULL;
 	mutex_unlock(&pndevs->lock);

 	if (pnd)
 		call_rcu(&pnd->rcu, phonet_device_rcu_free);

 	return err;
 }

 /* Gets a source address toward a destination, through a interface. */
 u8 phonet_address_get(struct net_device *dev, u8 daddr)
 {
 	struct phonet_device *pnd;
 	u8 saddr;

 	rcu_read_lock();
 	pnd = __phonet_get_rcu(dev);
 	if (pnd) {
 		BUG_ON(bitmap_empty(pnd->addrs, 64));

 		/* Use same source address as destination, if possible */
 		if (test_bit(daddr >> 2, pnd->addrs))
 			saddr = daddr;
 		else
 			saddr = find_first_bit(pnd->addrs, 64) << 2;
 	} else
 		saddr = PN_NO_ADDR;
 	rcu_read_unlock();

 	if (saddr == PN_NO_ADDR) {
 		/* Fallback to another device */
 		struct net_device *def_dev;

 		def_dev = phonet_device_get(dev_net(dev));
 		if (def_dev) {
 			if (def_dev != dev)
 				saddr = phonet_address_get(def_dev, daddr);
 			dev_put(def_dev);
 		}
 	}
 	return saddr;
 }

 int phonet_address_lookup(struct net *net, u8 addr)
 {
 	struct phonet_device_list *pndevs = phonet_device_list(net);
 	struct phonet_device *pnd;
 	int err = -EADDRNOTAVAIL;

 	rcu_read_lock();
 	list_for_each_entry_rcu(pnd, &pndevs->list, list) {
 		/* Don't allow unregistering devices! */
 		if ((pnd->netdev->reg_state != NETREG_REGISTERED) ||
 				((pnd->netdev->flags & IFF_UP)) != IFF_UP)
 			continue;

 		if (test_bit(addr >> 2, pnd->addrs)) {
 			err = 0;
 			goto found;
 		}
 	}
 found:
 	rcu_read_unlock();
 	return err;
 }

 /* automatically configure a Phonet device, if supported */
 static int phonet_device_autoconf(struct net_device *dev)
 {
 	struct if_phonet_req req;
 	int ret;

 	if (!dev->netdev_ops->ndo_do_ioctl)
 		return -EOPNOTSUPP;

 	ret = dev->netdev_ops->ndo_do_ioctl(dev, (struct ifreq *)&req,
 						SIOCPNGAUTOCONF);
 	if (ret < 0)
 		return ret;

 	ASSERT_RTNL();
 	ret = phonet_address_add(dev, req.ifr_phonet_autoconf.device);
 	if (ret)
 		return ret;
 	phonet_address_notify(RTM_NEWADDR, dev,
 				req.ifr_phonet_autoconf.device);
 	return 0;
 }

 static void phonet_route_autodel(struct net_device *dev)
 {
 	struct phonet_net *pnn = phonet_pernet(dev_net(dev));
 	unsigned i;
 	DECLARE_BITMAP(deleted, 64);

 	/* Remove left-over Phonet routes */
 	bitmap_zero(deleted, 64);
 	mutex_lock(&pnn->routes.lock);
 	for (i = 0; i < 64; i++)
 		if (dev == pnn->routes.table[i]) {
 			rcu_assign_pointer(pnn->routes.table[i], NULL);
 			set_bit(i, deleted);
 		}
 	mutex_unlock(&pnn->routes.lock);

 	if (bitmap_empty(deleted, 64))
 		return; /* short-circuit RCU */
 	synchronize_rcu();
 	for_each_set_bit(i, deleted, 64) {
 		rtm_phonet_notify(RTM_DELROUTE, dev, i);
 		dev_put(dev);
 	}
 }

 /* notify Phonet of device events */
 static int phonet_device_notify(struct notifier_block *me, unsigned long what,
 				void *arg)
 {
 	struct net_device *dev = arg;

 	switch (what) {
 	case NETDEV_REGISTER:
 		if (dev->type == ARPHRD_PHONET)
 			phonet_device_autoconf(dev);
 		break;
 	case NETDEV_UNREGISTER:
 		phonet_device_destroy(dev);
 		phonet_route_autodel(dev);
 		break;
 	}
 	return 0;

 }

 static struct notifier_block phonet_device_notifier = {
 	.notifier_call = phonet_device_notify,
 	.priority = 0,
 };

 /* Per-namespace Phonet devices handling */
 static int __net_init phonet_init_net(struct net *net)
 {
 	struct phonet_net *pnn = phonet_pernet(net);

 	if (!proc_net_fops_create(net, "phonet", 0, &pn_sock_seq_fops))
 		return -ENOMEM;

 	INIT_LIST_HEAD(&pnn->pndevs.list);
 	mutex_init(&pnn->pndevs.lock);
 	mutex_init(&pnn->routes.lock);
 	return 0;
 }

 static void __net_exit phonet_exit_net(struct net *net)
 {
 	struct phonet_net *pnn = phonet_pernet(net);
 	struct net_device *dev;
 	unsigned i;

 	rtnl_lock();
 	for_each_netdev(net, dev)
 		phonet_device_destroy(dev);

 	for (i = 0; i < 64; i++) {
 		dev = pnn->routes.table[i];
 		if (dev) {
 			rtm_phonet_notify(RTM_DELROUTE, dev, i);
 			dev_put(dev);
 		}
 	}
 	rtnl_unlock();

 	proc_net_remove(net, "phonet");
 }

 static struct pernet_operations phonet_net_ops = {
 	.init = phonet_init_net,
 	.exit = phonet_exit_net,
 	.id   = &phonet_net_id,
 	.size = sizeof(struct phonet_net),
 };

 /* Initialize Phonet devices list */
 int __init phonet_device_init(void)
 {
 	int err = register_pernet_device(&phonet_net_ops);
 	if (err)
 		return err;

 	proc_net_fops_create(&init_net, "pnresource", 0, &pn_res_seq_fops);
 	register_netdevice_notifier(&phonet_device_notifier);
 	err = phonet_netlink_register();
 	if (err)
 		phonet_device_exit();
 	return err;
 }

 void phonet_device_exit(void)
 {
 	rtnl_unregister_all(PF_PHONET);
 	unregister_netdevice_notifier(&phonet_device_notifier);
 	unregister_pernet_device(&phonet_net_ops);
 	proc_net_remove(&init_net, "pnresource");
 }

 int phonet_route_add(struct net_device *dev, u8 daddr)
 {
 	struct phonet_net *pnn = phonet_pernet(dev_net(dev));
 	struct phonet_routes *routes = &pnn->routes;
 	int err = -EEXIST;

 	daddr = daddr >> 2;
 	mutex_lock(&routes->lock);
 	if (routes->table[daddr] == NULL) {
 		rcu_assign_pointer(routes->table[daddr], dev);
 		dev_hold(dev);
 		err = 0;
 	}
 	mutex_unlock(&routes->lock);
 	return err;
 }

 int phonet_route_del(struct net_device *dev, u8 daddr)
 {
 	struct phonet_net *pnn = phonet_pernet(dev_net(dev));
 	struct phonet_routes *routes = &pnn->routes;

 	daddr = daddr >> 2;
 	mutex_lock(&routes->lock);
 	if (dev == routes->table[daddr])
 		rcu_assign_pointer(routes->table[daddr], NULL);
 	else
 		dev = NULL;
 	mutex_unlock(&routes->lock);

 	if (!dev)
 		return -ENOENT;
 	synchronize_rcu();
 	dev_put(dev);
 	return 0;
 }

 struct net_device *phonet_route_get(struct net *net, u8 daddr)
 {
 	struct phonet_net *pnn = phonet_pernet(net);
 	struct phonet_routes *routes = &pnn->routes;
 	struct net_device *dev;

 	ASSERT_RTNL(); /* no need to hold the device */

 	daddr >>= 2;
 	rcu_read_lock();
 	dev = rcu_dereference(routes->table[daddr]);
 	rcu_read_unlock();
 	return dev;
 }

 struct net_device *phonet_route_output(struct net *net, u8 daddr)
 {
 	struct phonet_net *pnn = phonet_pernet(net);
 	struct phonet_routes *routes = &pnn->routes;
 	struct net_device *dev;

 	daddr >>= 2;
 	rcu_read_lock();
 	dev = rcu_dereference(routes->table[daddr]);
 	if (dev)
 		dev_hold(dev);
 	rcu_read_unlock();

 	if (!dev)
 		dev = phonet_device_get(net); /* Default route */
 	return dev;
 }
	/*
	* File: pn_dev.c
	*
	* Phonet network device
	*
	* Copyright (C) 2008 Nokia Corporation.
	*
	* Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
	* Original author: Sakari Ailus <sakari.ailus@nokia.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* version 2 as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
	* 02110-1301 USA
	*/

	#include <linux/kernel.h>
	#include <linux/net.h>
	#include <linux/slab.h>
	#include <linux/netdevice.h>
	#include <linux/phonet.h>
	#include <linux/proc_fs.h>
	#include <linux/if_arp.h>
	#include <net/sock.h>
	#include <net/netns/generic.h>
	#include <net/phonet/pn_dev.h>

	struct phonet_routes {
	struct mutex lock;
	struct net_device *table[64];
	};

	struct phonet_net {
	struct phonet_device_list pndevs;
	struct phonet_routes routes;
	};

	int phonet_net_id __read_mostly;

	static struct phonet_net phonet_pernet(struct net net)
	{
	BUG_ON(!net);

	return net_generic(net, phonet_net_id);
	}

	struct phonet_device_list phonet_device_list(struct net net)
	{
	struct phonet_net *pnn = phonet_pernet(net);
	return &pnn->pndevs;
	}

	/* Allocate new Phonet device. */
	static struct phonet_device __phonet_device_alloc(struct net_device dev)
	{
	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
	struct phonet_device pnd = kmalloc(sizeof(pnd), GFP_ATOMIC);
	if (pnd == NULL)
	return NULL;
	pnd->netdev = dev;
	bitmap_zero(pnd->addrs, 64);

	BUG_ON(!mutex_is_locked(&pndevs->lock));
	list_add_rcu(&pnd->list, &pndevs->list);
	return pnd;
	}

	static struct phonet_device __phonet_get(struct net_device dev)
	{
	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
	struct phonet_device *pnd;

	BUG_ON(!mutex_is_locked(&pndevs->lock));
	list_for_each_entry(pnd, &pndevs->list, list) {
	if (pnd->netdev == dev)
	return pnd;
	}
	return NULL;
	}

	static struct phonet_device __phonet_get_rcu(struct net_device dev)
	{
	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
	struct phonet_device *pnd;

	list_for_each_entry_rcu(pnd, &pndevs->list, list) {
	if (pnd->netdev == dev)
	return pnd;
	}
	return NULL;
	}

	static void phonet_device_destroy(struct net_device *dev)
	{
	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
	struct phonet_device *pnd;

	ASSERT_RTNL();

	mutex_lock(&pndevs->lock);
	pnd = __phonet_get(dev);
	if (pnd)
	list_del_rcu(&pnd->list);
	mutex_unlock(&pndevs->lock);

	if (pnd) {
	u8 addr;

	for_each_set_bit(addr, pnd->addrs, 64)
	phonet_address_notify(RTM_DELADDR, dev, addr);
	kfree(pnd);
	}
	}

	struct net_device phonet_device_get(struct net net)
	{
	struct phonet_device_list *pndevs = phonet_device_list(net);
	struct phonet_device *pnd;
	struct net_device *dev = NULL;

	rcu_read_lock();
	list_for_each_entry_rcu(pnd, &pndevs->list, list) {
	dev = pnd->netdev;
	BUG_ON(!dev);

	if ((dev->reg_state == NETREG_REGISTERED) &&
	((pnd->netdev->flags & IFF_UP)) == IFF_UP)
	break;
	dev = NULL;
	}
	if (dev)
	dev_hold(dev);
	rcu_read_unlock();
	return dev;
	}

	int phonet_address_add(struct net_device *dev, u8 addr)
	{
	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
	struct phonet_device *pnd;
	int err = 0;

	mutex_lock(&pndevs->lock);
	/* Find or create Phonet-specific device data */
	pnd = __phonet_get(dev);
	if (pnd == NULL)
	pnd = __phonet_device_alloc(dev);
	if (unlikely(pnd == NULL))
	err = -ENOMEM;
	else if (test_and_set_bit(addr >> 2, pnd->addrs))
	err = -EEXIST;
	mutex_unlock(&pndevs->lock);
	return err;
	}

	static void phonet_device_rcu_free(struct rcu_head *head)
	{
	struct phonet_device *pnd;

	pnd = container_of(head, struct phonet_device, rcu);
	kfree(pnd);
	}

	int phonet_address_del(struct net_device *dev, u8 addr)
	{
	struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
	struct phonet_device *pnd;
	int err = 0;

	mutex_lock(&pndevs->lock);
	pnd = __phonet_get(dev);
	if (!pnd \|\| !test_and_clear_bit(addr >> 2, pnd->addrs)) {
	err = -EADDRNOTAVAIL;
	pnd = NULL;
	} else if (bitmap_empty(pnd->addrs, 64))
	list_del_rcu(&pnd->list);
	else
	pnd = NULL;
	mutex_unlock(&pndevs->lock);

	if (pnd)
	call_rcu(&pnd->rcu, phonet_device_rcu_free);

	return err;
	}

	/* Gets a source address toward a destination, through a interface. */
	u8 phonet_address_get(struct net_device *dev, u8 daddr)
	{
	struct phonet_device *pnd;
	u8 saddr;

	rcu_read_lock();
	pnd = __phonet_get_rcu(dev);
	if (pnd) {
	BUG_ON(bitmap_empty(pnd->addrs, 64));

	/* Use same source address as destination, if possible */
	if (test_bit(daddr >> 2, pnd->addrs))
	saddr = daddr;
	else
	saddr = find_first_bit(pnd->addrs, 64) << 2;
	} else
	saddr = PN_NO_ADDR;
	rcu_read_unlock();

	if (saddr == PN_NO_ADDR) {
	/* Fallback to another device */
	struct net_device *def_dev;

	def_dev = phonet_device_get(dev_net(dev));
	if (def_dev) {
	if (def_dev != dev)
	saddr = phonet_address_get(def_dev, daddr);
	dev_put(def_dev);
	}
	}
	return saddr;
	}

	int phonet_address_lookup(struct net *net, u8 addr)
	{
	struct phonet_device_list *pndevs = phonet_device_list(net);
	struct phonet_device *pnd;
	int err = -EADDRNOTAVAIL;

	rcu_read_lock();
	list_for_each_entry_rcu(pnd, &pndevs->list, list) {
	/* Don't allow unregistering devices! */
	if ((pnd->netdev->reg_state != NETREG_REGISTERED) \|\|
	((pnd->netdev->flags & IFF_UP)) != IFF_UP)
	continue;

	if (test_bit(addr >> 2, pnd->addrs)) {
	err = 0;
	goto found;
	}
	}
	found:
	rcu_read_unlock();
	return err;
	}

	/* automatically configure a Phonet device, if supported */
	static int phonet_device_autoconf(struct net_device *dev)
	{
	struct if_phonet_req req;
	int ret;

	if (!dev->netdev_ops->ndo_do_ioctl)
	return -EOPNOTSUPP;

	ret = dev->netdev_ops->ndo_do_ioctl(dev, (struct ifreq *)&req,
	SIOCPNGAUTOCONF);
	if (ret < 0)
	return ret;

	ASSERT_RTNL();
	ret = phonet_address_add(dev, req.ifr_phonet_autoconf.device);
	if (ret)
	return ret;
	phonet_address_notify(RTM_NEWADDR, dev,
	req.ifr_phonet_autoconf.device);
	return 0;
	}

	static void phonet_route_autodel(struct net_device *dev)
	{
	struct phonet_net *pnn = phonet_pernet(dev_net(dev));
	unsigned i;
	DECLARE_BITMAP(deleted, 64);

	/* Remove left-over Phonet routes */
	bitmap_zero(deleted, 64);
	mutex_lock(&pnn->routes.lock);
	for (i = 0; i < 64; i++)
	if (dev == pnn->routes.table[i]) {
	rcu_assign_pointer(pnn->routes.table[i], NULL);
	set_bit(i, deleted);
	}
	mutex_unlock(&pnn->routes.lock);

	if (bitmap_empty(deleted, 64))
	return; /* short-circuit RCU */
	synchronize_rcu();
	for_each_set_bit(i, deleted, 64) {
	rtm_phonet_notify(RTM_DELROUTE, dev, i);
	dev_put(dev);
	}
	}

	/* notify Phonet of device events */
	static int phonet_device_notify(struct notifier_block *me, unsigned long what,
	void *arg)
	{
	struct net_device *dev = arg;

	switch (what) {
	case NETDEV_REGISTER:
	if (dev->type == ARPHRD_PHONET)
	phonet_device_autoconf(dev);
	break;
	case NETDEV_UNREGISTER:
	phonet_device_destroy(dev);
	phonet_route_autodel(dev);
	break;
	}
	return 0;

	}

	static struct notifier_block phonet_device_notifier = {
	.notifier_call = phonet_device_notify,
	.priority = 0,
	};

	/* Per-namespace Phonet devices handling */
	static int __net_init phonet_init_net(struct net *net)
	{
	struct phonet_net *pnn = phonet_pernet(net);

	if (!proc_net_fops_create(net, "phonet", 0, &pn_sock_seq_fops))
	return -ENOMEM;

	INIT_LIST_HEAD(&pnn->pndevs.list);
	mutex_init(&pnn->pndevs.lock);
	mutex_init(&pnn->routes.lock);
	return 0;
	}

	static void __net_exit phonet_exit_net(struct net *net)
	{
	struct phonet_net *pnn = phonet_pernet(net);
	struct net_device *dev;
	unsigned i;

	rtnl_lock();
	for_each_netdev(net, dev)
	phonet_device_destroy(dev);

	for (i = 0; i < 64; i++) {
	dev = pnn->routes.table[i];
	if (dev) {
	rtm_phonet_notify(RTM_DELROUTE, dev, i);
	dev_put(dev);
	}
	}
	rtnl_unlock();

	proc_net_remove(net, "phonet");
	}

	static struct pernet_operations phonet_net_ops = {
	.init = phonet_init_net,
	.exit = phonet_exit_net,
	.id = &phonet_net_id,
	.size = sizeof(struct phonet_net),
	};

	/* Initialize Phonet devices list */
	int __init phonet_device_init(void)
	{
	int err = register_pernet_device(&phonet_net_ops);
	if (err)
	return err;

	proc_net_fops_create(&init_net, "pnresource", 0, &pn_res_seq_fops);
	register_netdevice_notifier(&phonet_device_notifier);
	err = phonet_netlink_register();
	if (err)
	phonet_device_exit();
	return err;
	}

	void phonet_device_exit(void)
	{
	rtnl_unregister_all(PF_PHONET);
	unregister_netdevice_notifier(&phonet_device_notifier);
	unregister_pernet_device(&phonet_net_ops);
	proc_net_remove(&init_net, "pnresource");
	}

	int phonet_route_add(struct net_device *dev, u8 daddr)
	{
	struct phonet_net *pnn = phonet_pernet(dev_net(dev));
	struct phonet_routes *routes = &pnn->routes;
	int err = -EEXIST;

	daddr = daddr >> 2;
	mutex_lock(&routes->lock);
	if (routes->table[daddr] == NULL) {
	rcu_assign_pointer(routes->table[daddr], dev);
	dev_hold(dev);
	err = 0;
	}
	mutex_unlock(&routes->lock);
	return err;
	}

	int phonet_route_del(struct net_device *dev, u8 daddr)
	{
	struct phonet_net *pnn = phonet_pernet(dev_net(dev));
	struct phonet_routes *routes = &pnn->routes;

	daddr = daddr >> 2;
	mutex_lock(&routes->lock);
	if (dev == routes->table[daddr])
	rcu_assign_pointer(routes->table[daddr], NULL);
	else
	dev = NULL;
	mutex_unlock(&routes->lock);

	if (!dev)
	return -ENOENT;
	synchronize_rcu();
	dev_put(dev);
	return 0;
	}

	struct net_device phonet_route_get(struct net net, u8 daddr)
	{
	struct phonet_net *pnn = phonet_pernet(net);
	struct phonet_routes *routes = &pnn->routes;
	struct net_device *dev;

	ASSERT_RTNL(); /* no need to hold the device */

	daddr >>= 2;
	rcu_read_lock();
	dev = rcu_dereference(routes->table[daddr]);
	rcu_read_unlock();
	return dev;
	}

	struct net_device phonet_route_output(struct net net, u8 daddr)
	{
	struct phonet_net *pnn = phonet_pernet(net);
	struct phonet_routes *routes = &pnn->routes;
	struct net_device *dev;

	daddr >>= 2;
	rcu_read_lock();
	dev = rcu_dereference(routes->table[daddr]);
	if (dev)
	dev_hold(dev);
	rcu_read_unlock();

	if (!dev)
	dev = phonet_device_get(net); /* Default route */
	return dev;
	}