[deliverable/linux.git] / drivers / net / veth.c

/*
 *  drivers/net/veth.c
 *
 *  Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc
 *
 * Author: Pavel Emelianov <xemul@openvz.org>
 * Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com>
 *
 */

#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/ethtool.h>
#include <linux/etherdevice.h>

#include <net/dst.h>
#include <net/xfrm.h>
#include <net/veth.h>

#define DRV_NAME	"veth"
#define DRV_VERSION	"1.0"

struct veth_net_stats {
	unsigned long	rx_packets;
	unsigned long	tx_packets;
	unsigned long	rx_bytes;
	unsigned long	tx_bytes;
	unsigned long	tx_dropped;
};

struct veth_priv {
	struct net_device *peer;
	struct net_device *dev;
	struct list_head list;
	struct veth_net_stats *stats;
	unsigned ip_summed;
};

static LIST_HEAD(veth_list);

/*
 * ethtool interface
 */

static struct {
	const char string[ETH_GSTRING_LEN];
} ethtool_stats_keys[] = {
	{ "peer_ifindex" },
};

static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
	cmd->supported		= 0;
	cmd->advertising	= 0;
	cmd->speed		= SPEED_10000;
	cmd->duplex		= DUPLEX_FULL;
	cmd->port		= PORT_TP;
	cmd->phy_address	= 0;
	cmd->transceiver	= XCVR_INTERNAL;
	cmd->autoneg		= AUTONEG_DISABLE;
	cmd->maxtxpkt		= 0;
	cmd->maxrxpkt		= 0;
	return 0;
}

static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
{
	strcpy(info->driver, DRV_NAME);
	strcpy(info->version, DRV_VERSION);
	strcpy(info->fw_version, "N/A");
}

static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
{
	switch(stringset) {
	case ETH_SS_STATS:
		memcpy(buf, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
		break;
	}
}

static int veth_get_sset_count(struct net_device *dev, int sset)
{
	switch (sset) {
	case ETH_SS_STATS:
		return ARRAY_SIZE(ethtool_stats_keys);
	default:
		return -EOPNOTSUPP;
	}
}

static void veth_get_ethtool_stats(struct net_device *dev,
		struct ethtool_stats *stats, u64 *data)
{
	struct veth_priv *priv;

	priv = netdev_priv(dev);
	data[0] = priv->peer->ifindex;
}

static u32 veth_get_rx_csum(struct net_device *dev)
{
	struct veth_priv *priv;

	priv = netdev_priv(dev);
	return priv->ip_summed == CHECKSUM_UNNECESSARY;
}

static int veth_set_rx_csum(struct net_device *dev, u32 data)
{
	struct veth_priv *priv;

	priv = netdev_priv(dev);
	priv->ip_summed = data ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
	return 0;
}

static u32 veth_get_tx_csum(struct net_device *dev)
{
	return (dev->features & NETIF_F_NO_CSUM) != 0;
}

static int veth_set_tx_csum(struct net_device *dev, u32 data)
{
	if (data)
		dev->features |= NETIF_F_NO_CSUM;
	else
		dev->features &= ~NETIF_F_NO_CSUM;
	return 0;
}

static struct ethtool_ops veth_ethtool_ops = {
	.get_settings		= veth_get_settings,
	.get_drvinfo		= veth_get_drvinfo,
	.get_link		= ethtool_op_get_link,
	.get_rx_csum		= veth_get_rx_csum,
	.set_rx_csum		= veth_set_rx_csum,
	.get_tx_csum		= veth_get_tx_csum,
	.set_tx_csum		= veth_set_tx_csum,
	.get_sg			= ethtool_op_get_sg,
	.set_sg			= ethtool_op_set_sg,
	.get_strings		= veth_get_strings,
	.get_sset_count		= veth_get_sset_count,
	.get_ethtool_stats	= veth_get_ethtool_stats,
};

/*
 * xmit
 */

static int veth_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct net_device *rcv = NULL;
	struct veth_priv *priv, *rcv_priv;
	struct veth_net_stats *stats;
	int length, cpu;

	skb_orphan(skb);

	priv = netdev_priv(dev);
	rcv = priv->peer;
	rcv_priv = netdev_priv(rcv);

	cpu = smp_processor_id();
	stats = per_cpu_ptr(priv->stats, cpu);

	if (!(rcv->flags & IFF_UP))
		goto outf;

	skb->pkt_type = PACKET_HOST;
	skb->protocol = eth_type_trans(skb, rcv);
	if (dev->features & NETIF_F_NO_CSUM)
		skb->ip_summed = rcv_priv->ip_summed;

	dst_release(skb->dst);
	skb->dst = NULL;
	skb->mark = 0;
	secpath_reset(skb);
	nf_reset(skb);

	length = skb->len;

	stats->tx_bytes += length;
	stats->tx_packets++;

	stats = per_cpu_ptr(rcv_priv->stats, cpu);
	stats->rx_bytes += length;
	stats->rx_packets++;

	netif_rx(skb);
	return 0;

outf:
	kfree_skb(skb);
	stats->tx_dropped++;
	return 0;
}

/*
 * general routines
 */

static struct net_device_stats *veth_get_stats(struct net_device *dev)
{
	struct veth_priv *priv;
	struct net_device_stats *dev_stats;
	int cpu;
	struct veth_net_stats *stats;

	priv = netdev_priv(dev);
	dev_stats = &dev->stats;

	dev_stats->rx_packets = 0;
	dev_stats->tx_packets = 0;
	dev_stats->rx_bytes = 0;
	dev_stats->tx_bytes = 0;
	dev_stats->tx_dropped = 0;

	for_each_online_cpu(cpu) {
		stats = per_cpu_ptr(priv->stats, cpu);

		dev_stats->rx_packets += stats->rx_packets;
		dev_stats->tx_packets += stats->tx_packets;
		dev_stats->rx_bytes += stats->rx_bytes;
		dev_stats->tx_bytes += stats->tx_bytes;
		dev_stats->tx_dropped += stats->tx_dropped;
	}

	return dev_stats;
}

static int veth_open(struct net_device *dev)
{
	struct veth_priv *priv;

	priv = netdev_priv(dev);
	if (priv->peer == NULL)
		return -ENOTCONN;

	if (priv->peer->flags & IFF_UP) {
		netif_carrier_on(dev);
		netif_carrier_on(priv->peer);
	}
	return 0;
}

static int veth_close(struct net_device *dev)
{
	struct veth_priv *priv;

	if (netif_carrier_ok(dev)) {
		priv = netdev_priv(dev);
		netif_carrier_off(dev);
		netif_carrier_off(priv->peer);
	}
	return 0;
}

static int veth_dev_init(struct net_device *dev)
{
	struct veth_net_stats *stats;
	struct veth_priv *priv;

	stats = alloc_percpu(struct veth_net_stats);
	if (stats == NULL)
		return -ENOMEM;

	priv = netdev_priv(dev);
	priv->stats = stats;
	return 0;
}

static void veth_dev_free(struct net_device *dev)
{
	struct veth_priv *priv;

	priv = netdev_priv(dev);
	free_percpu(priv->stats);
	free_netdev(dev);
}

static void veth_setup(struct net_device *dev)
{
	ether_setup(dev);

	dev->hard_start_xmit = veth_xmit;
	dev->get_stats = veth_get_stats;
	dev->open = veth_open;
	dev->stop = veth_close;
	dev->ethtool_ops = &veth_ethtool_ops;
	dev->features |= NETIF_F_LLTX;
	dev->init = veth_dev_init;
	dev->destructor = veth_dev_free;
}

/*
 * netlink interface
 */

static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
{
	if (tb[IFLA_ADDRESS]) {
		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
			return -EINVAL;
		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
			return -EADDRNOTAVAIL;
	}
	return 0;
}

static struct rtnl_link_ops veth_link_ops;

static int veth_newlink(struct net_device *dev,
			 struct nlattr *tb[], struct nlattr *data[])
{
	int err;
	struct net_device *peer;
	struct veth_priv *priv;
	char ifname[IFNAMSIZ];
	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;

	/*
	 * create and register peer first
	 *
	 * struct ifinfomsg is at the head of VETH_INFO_PEER, but we
	 * skip it since no info from it is useful yet
	 */

	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
		struct nlattr *nla_peer;

		nla_peer = data[VETH_INFO_PEER];
		err = nla_parse(peer_tb, IFLA_MAX,
				nla_data(nla_peer) + sizeof(struct ifinfomsg),
				nla_len(nla_peer) - sizeof(struct ifinfomsg),
				ifla_policy);
		if (err < 0)
			return err;

		err = veth_validate(peer_tb, NULL);
		if (err < 0)
			return err;

		tbp = peer_tb;
	} else
		tbp = tb;

	if (tbp[IFLA_IFNAME])
		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
	else
		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");

	peer = rtnl_create_link(dev->nd_net, ifname, &veth_link_ops, tbp);
	if (IS_ERR(peer))
		return PTR_ERR(peer);

	if (tbp[IFLA_ADDRESS] == NULL)
		random_ether_addr(peer->dev_addr);

	err = register_netdevice(peer);
	if (err < 0)
		goto err_register_peer;

	netif_carrier_off(peer);

	/*
	 * register dev last
	 *
	 * note, that since we've registered new device the dev's name
	 * should be re-allocated
	 */

	if (tb[IFLA_ADDRESS] == NULL)
		random_ether_addr(dev->dev_addr);

	if (tb[IFLA_IFNAME])
		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
	else
		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");

	if (strchr(dev->name, '%')) {
		err = dev_alloc_name(dev, dev->name);
		if (err < 0)
			goto err_alloc_name;
	}

	err = register_netdevice(dev);
	if (err < 0)
		goto err_register_dev;

	netif_carrier_off(dev);

	/*
	 * tie the deviced together
	 */

	priv = netdev_priv(dev);
	priv->dev = dev;
	priv->peer = peer;
	list_add(&priv->list, &veth_list);

	priv = netdev_priv(peer);
	priv->dev = peer;
	priv->peer = dev;
	INIT_LIST_HEAD(&priv->list);
	return 0;

err_register_dev:
	/* nothing to do */
err_alloc_name:
	unregister_netdevice(peer);
	return err;

err_register_peer:
	free_netdev(peer);
	return err;
}

static void veth_dellink(struct net_device *dev)
{
	struct veth_priv *priv;
	struct net_device *peer;

	priv = netdev_priv(dev);
	peer = priv->peer;

	if (!list_empty(&priv->list))
		list_del(&priv->list);

	priv = netdev_priv(peer);
	if (!list_empty(&priv->list))
		list_del(&priv->list);

	unregister_netdevice(dev);
	unregister_netdevice(peer);
}

static const struct nla_policy veth_policy[VETH_INFO_MAX + 1];

static struct rtnl_link_ops veth_link_ops = {
	.kind		= DRV_NAME,
	.priv_size	= sizeof(struct veth_priv),
	.setup		= veth_setup,
	.validate	= veth_validate,
	.newlink	= veth_newlink,
	.dellink	= veth_dellink,
	.policy		= veth_policy,
	.maxtype	= VETH_INFO_MAX,
};

/*
 * init/fini
 */

static __init int veth_init(void)
{
	return rtnl_link_register(&veth_link_ops);
}

static __exit void veth_exit(void)
{
	struct veth_priv *priv, *next;

	rtnl_lock();
	/*
	 * cannot trust __rtnl_link_unregister() to unregister all
	 * devices, as each ->dellink call will remove two devices
	 * from the list at once.
	 */
	list_for_each_entry_safe(priv, next, &veth_list, list)
		veth_dellink(priv->dev);

	__rtnl_link_unregister(&veth_link_ops);
	rtnl_unlock();
}

module_init(veth_init);
module_exit(veth_exit);

MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS_RTNL_LINK(DRV_NAME);
Commit	Line	Data
e314dbdc PE	1	/*
	2	* drivers/net/veth.c
	3	*
	4	* Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc
	5	*
	6	* Author: Pavel Emelianov <xemul@openvz.org>
	7	* Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com>
	8	*
	9	*/
	10
	11	#include <linux/list.h>
	12	#include <linux/netdevice.h>
	13	#include <linux/ethtool.h>
	14	#include <linux/etherdevice.h>
	15
	16	#include <net/dst.h>
	17	#include <net/xfrm.h>
	18	#include <net/veth.h>
	19
	20	#define DRV_NAME "veth"
	21	#define DRV_VERSION "1.0"
	22
	23	struct veth_net_stats {
	24	unsigned long rx_packets;
	25	unsigned long tx_packets;
	26	unsigned long rx_bytes;
	27	unsigned long tx_bytes;
	28	unsigned long tx_dropped;
	29	};
	30
	31	struct veth_priv {
	32	struct net_device *peer;
	33	struct net_device *dev;
	34	struct list_head list;
	35	struct veth_net_stats *stats;
	36	unsigned ip_summed;
	37	};
	38
	39	static LIST_HEAD(veth_list);
	40
	41	/*
	42	* ethtool interface
	43	*/
	44
	45	static struct {
	46	const char string[ETH_GSTRING_LEN];
	47	} ethtool_stats_keys[] = {
	48	{ "peer_ifindex" },
	49	};
	50
	51	static int veth_get_settings(struct net_device dev, struct ethtool_cmd cmd)
	52	{
	53	cmd->supported = 0;
	54	cmd->advertising = 0;
	55	cmd->speed = SPEED_10000;
	56	cmd->duplex = DUPLEX_FULL;
	57	cmd->port = PORT_TP;
	58	cmd->phy_address = 0;
	59	cmd->transceiver = XCVR_INTERNAL;
	60	cmd->autoneg = AUTONEG_DISABLE;
	61	cmd->maxtxpkt = 0;
	62	cmd->maxrxpkt = 0;
	63	return 0;
	64	}
65
66	static void veth_get_drvinfo(struct net_device dev, struct ethtool_drvinfo info)
67	{
68	strcpy(info->driver, DRV_NAME);
69	strcpy(info->version, DRV_VERSION);
70	strcpy(info->fw_version, "N/A");
71	}
72
73	static void veth_get_strings(struct net_device dev, u32 stringset, u8 buf)
74	{
75	switch(stringset) {
76	case ETH_SS_STATS:
77	memcpy(buf, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
78	break;
79	}
80	}
81
b9f2c044	82	static int veth_get_sset_count(struct net_device *dev, int sset)
e314dbdc	83	{
b9f2c044 JG	84	switch (sset) {
	85	case ETH_SS_STATS:
	86	return ARRAY_SIZE(ethtool_stats_keys);
	87	default:
	88	return -EOPNOTSUPP;
	89	}
e314dbdc PE	90	}
	91
	92	static void veth_get_ethtool_stats(struct net_device *dev,
	93	struct ethtool_stats stats, u64 data)
	94	{
	95	struct veth_priv *priv;
	96
	97	priv = netdev_priv(dev);
	98	data[0] = priv->peer->ifindex;
	99	}
	100
	101	static u32 veth_get_rx_csum(struct net_device *dev)
	102	{
	103	struct veth_priv *priv;
	104
	105	priv = netdev_priv(dev);
	106	return priv->ip_summed == CHECKSUM_UNNECESSARY;
	107	}
	108
	109	static int veth_set_rx_csum(struct net_device *dev, u32 data)
	110	{
	111	struct veth_priv *priv;
	112
	113	priv = netdev_priv(dev);
	114	priv->ip_summed = data ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
	115	return 0;
	116	}
	117
	118	static u32 veth_get_tx_csum(struct net_device *dev)
	119	{
	120	return (dev->features & NETIF_F_NO_CSUM) != 0;
	121	}
	122
	123	static int veth_set_tx_csum(struct net_device *dev, u32 data)
	124	{
	125	if (data)
	126	dev->features \|= NETIF_F_NO_CSUM;
	127	else
	128	dev->features &= ~NETIF_F_NO_CSUM;
	129	return 0;
	130	}
	131
	132	static struct ethtool_ops veth_ethtool_ops = {
	133	.get_settings = veth_get_settings,
	134	.get_drvinfo = veth_get_drvinfo,
	135	.get_link = ethtool_op_get_link,
	136	.get_rx_csum = veth_get_rx_csum,
	137	.set_rx_csum = veth_set_rx_csum,
	138	.get_tx_csum = veth_get_tx_csum,
	139	.set_tx_csum = veth_set_tx_csum,
	140	.get_sg = ethtool_op_get_sg,
	141	.set_sg = ethtool_op_set_sg,
	142	.get_strings = veth_get_strings,
b9f2c044	143	.get_sset_count = veth_get_sset_count,
e314dbdc PE	144	.get_ethtool_stats = veth_get_ethtool_stats,
	145	};
	146
	147	/*
	148	* xmit
	149	*/
	150
	151	static int veth_xmit(struct sk_buff skb, struct net_device dev)
	152	{
	153	struct net_device *rcv = NULL;
	154	struct veth_priv priv, rcv_priv;
	155	struct veth_net_stats *stats;
	156	int length, cpu;
	157
	158	skb_orphan(skb);
	159
	160	priv = netdev_priv(dev);
	161	rcv = priv->peer;
	162	rcv_priv = netdev_priv(rcv);
	163
	164	cpu = smp_processor_id();
	165	stats = per_cpu_ptr(priv->stats, cpu);
	166
	167	if (!(rcv->flags & IFF_UP))
	168	goto outf;
	169
	170	skb->pkt_type = PACKET_HOST;
	171	skb->protocol = eth_type_trans(skb, rcv);
	172	if (dev->features & NETIF_F_NO_CSUM)
	173	skb->ip_summed = rcv_priv->ip_summed;
	174
	175	dst_release(skb->dst);
	176	skb->dst = NULL;
	177	skb->mark = 0;
	178	secpath_reset(skb);
	179	nf_reset(skb);
	180
	181	length = skb->len;
	182
	183	stats->tx_bytes += length;
	184	stats->tx_packets++;
	185
	186	stats = per_cpu_ptr(rcv_priv->stats, cpu);
	187	stats->rx_bytes += length;
	188	stats->rx_packets++;
	189
	190	netif_rx(skb);
	191	return 0;
	192
	193	outf:
	194	kfree_skb(skb);
	195	stats->tx_dropped++;
	196	return 0;
	197	}
	198
	199	/*
	200	* general routines
	201	*/
	202
	203	static struct net_device_stats veth_get_stats(struct net_device dev)
	204	{
	205	struct veth_priv *priv;
	206	struct net_device_stats *dev_stats;
	207	int cpu;
208	struct veth_net_stats *stats;
209
210	priv = netdev_priv(dev);
211	dev_stats = &dev->stats;
212
213	dev_stats->rx_packets = 0;
214	dev_stats->tx_packets = 0;
215	dev_stats->rx_bytes = 0;
216	dev_stats->tx_bytes = 0;
217	dev_stats->tx_dropped = 0;
218
219	for_each_online_cpu(cpu) {
220	stats = per_cpu_ptr(priv->stats, cpu);
221
222	dev_stats->rx_packets += stats->rx_packets;
223	dev_stats->tx_packets += stats->tx_packets;
224	dev_stats->rx_bytes += stats->rx_bytes;
225	dev_stats->tx_bytes += stats->tx_bytes;
226	dev_stats->tx_dropped += stats->tx_dropped;
227	}
228
229	return dev_stats;
230	}
231
232	static int veth_open(struct net_device *dev)
233	{
234	struct veth_priv *priv;
235
236	priv = netdev_priv(dev);
237	if (priv->peer == NULL)
238	return -ENOTCONN;
239
240	if (priv->peer->flags & IFF_UP) {
241	netif_carrier_on(dev);
242	netif_carrier_on(priv->peer);
243	}
244	return 0;
245	}
246
247	static int veth_close(struct net_device *dev)
248	{
249	struct veth_priv *priv;
250
251	if (netif_carrier_ok(dev)) {
252	priv = netdev_priv(dev);
253	netif_carrier_off(dev);
254	netif_carrier_off(priv->peer);
255	}
256	return 0;
257	}
258
259	static int veth_dev_init(struct net_device *dev)
260	{
261	struct veth_net_stats *stats;
262	struct veth_priv *priv;
263
264	stats = alloc_percpu(struct veth_net_stats);
265	if (stats == NULL)
266	return -ENOMEM;
267
268	priv = netdev_priv(dev);
269	priv->stats = stats;
270	return 0;
271	}
272
273	static void veth_dev_free(struct net_device *dev)
274	{
275	struct veth_priv *priv;
276
277	priv = netdev_priv(dev);
278	free_percpu(priv->stats);
279	free_netdev(dev);
280	}
281
282	static void veth_setup(struct net_device *dev)
283	{
284	ether_setup(dev);
285
286	dev->hard_start_xmit = veth_xmit;
287	dev->get_stats = veth_get_stats;
288	dev->open = veth_open;
289	dev->stop = veth_close;
290	dev->ethtool_ops = &veth_ethtool_ops;
291	dev->features \|= NETIF_F_LLTX;
292	dev->init = veth_dev_init;
293	dev->destructor = veth_dev_free;
294	}
295
296	/*
297	* netlink interface
298	*/
299
300	static int veth_validate(struct nlattr tb[], struct nlattr data[])
301	{
302	if (tb[IFLA_ADDRESS]) {
303	if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
304	return -EINVAL;
305	if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
306	return -EADDRNOTAVAIL;
307	}
308	return 0;
309	}
310
311	static struct rtnl_link_ops veth_link_ops;
312
313	static int veth_newlink(struct net_device *dev,
314	struct nlattr tb[], struct nlattr data[])
315	{
316	int err;
317	struct net_device *peer;
318	struct veth_priv *priv;
319	char ifname[IFNAMSIZ];
320	struct nlattr peer_tb[IFLA_MAX + 1], *tbp;
321
322	/*
323	* create and register peer first
324	*
325	* struct ifinfomsg is at the head of VETH_INFO_PEER, but we
326	* skip it since no info from it is useful yet
327	*/
328
329	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
330	struct nlattr *nla_peer;
331
332	nla_peer = data[VETH_INFO_PEER];
333	err = nla_parse(peer_tb, IFLA_MAX,
334	nla_data(nla_peer) + sizeof(struct ifinfomsg),
335	nla_len(nla_peer) - sizeof(struct ifinfomsg),
336	ifla_policy);
337	if (err < 0)
338	return err;
339
340	err = veth_validate(peer_tb, NULL);
341	if (err < 0)
342	return err;
343
344	tbp = peer_tb;
345	} else
346	tbp = tb;
347
348	if (tbp[IFLA_IFNAME])
349	nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
350	else
351	snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
352
881d966b	353	peer = rtnl_create_link(dev->nd_net, ifname, &veth_link_ops, tbp);
e314dbdc PE	354	if (IS_ERR(peer))
	355	return PTR_ERR(peer);
	356
	357	if (tbp[IFLA_ADDRESS] == NULL)
	358	random_ether_addr(peer->dev_addr);
	359
	360	err = register_netdevice(peer);
	361	if (err < 0)
	362	goto err_register_peer;
	363
	364	netif_carrier_off(peer);
	365
	366	/*
	367	* register dev last
	368	*
	369	* note, that since we've registered new device the dev's name
	370	* should be re-allocated
	371	*/
	372
	373	if (tb[IFLA_ADDRESS] == NULL)
	374	random_ether_addr(dev->dev_addr);
	375
	376	if (tb[IFLA_IFNAME])
	377	nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
	378	else
	379	snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
	380
	381	if (strchr(dev->name, '%')) {
	382	err = dev_alloc_name(dev, dev->name);
	383	if (err < 0)
	384	goto err_alloc_name;
	385	}
	386
	387	err = register_netdevice(dev);
	388	if (err < 0)
	389	goto err_register_dev;
	390
	391	netif_carrier_off(dev);
	392
	393	/*
	394	* tie the deviced together
	395	*/
	396
	397	priv = netdev_priv(dev);
	398	priv->dev = dev;
	399	priv->peer = peer;
	400	list_add(&priv->list, &veth_list);
	401
	402	priv = netdev_priv(peer);
	403	priv->dev = peer;
	404	priv->peer = dev;
	405	INIT_LIST_HEAD(&priv->list);
	406	return 0;
	407
	408	err_register_dev:
	409	/* nothing to do */
	410	err_alloc_name:
	411	unregister_netdevice(peer);
	412	return err;
	413
	414	err_register_peer:
	415	free_netdev(peer);
	416	return err;
	417	}
418
419	static void veth_dellink(struct net_device *dev)
420	{
421	struct veth_priv *priv;
422	struct net_device *peer;
423
424	priv = netdev_priv(dev);
425	peer = priv->peer;
426
427	if (!list_empty(&priv->list))
428	list_del(&priv->list);
429
430	priv = netdev_priv(peer);
431	if (!list_empty(&priv->list))
432	list_del(&priv->list);
433
434	unregister_netdevice(dev);
435	unregister_netdevice(peer);
436	}
437
438	static const struct nla_policy veth_policy[VETH_INFO_MAX + 1];
439
440	static struct rtnl_link_ops veth_link_ops = {
441	.kind = DRV_NAME,
442	.priv_size = sizeof(struct veth_priv),
443	.setup = veth_setup,
444	.validate = veth_validate,
445	.newlink = veth_newlink,
446	.dellink = veth_dellink,
447	.policy = veth_policy,
448	.maxtype = VETH_INFO_MAX,
449	};
450
451	/*
452	* init/fini
453	*/
454
455	static __init int veth_init(void)
456	{
457	return rtnl_link_register(&veth_link_ops);
458	}
459
460	static __exit void veth_exit(void)
461	{
462	struct veth_priv priv, next;
463
464	rtnl_lock();
465	/*
466	* cannot trust __rtnl_link_unregister() to unregister all
467	* devices, as each ->dellink call will remove two devices
468	* from the list at once.
469	*/
470	list_for_each_entry_safe(priv, next, &veth_list, list)
471	veth_dellink(priv->dev);
472
473	__rtnl_link_unregister(&veth_link_ops);
474	rtnl_unlock();
475	}
476
477	module_init(veth_init);
478	module_exit(veth_exit);
479
480	MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
481	MODULE_LICENSE("GPL v2");
482	MODULE_ALIAS_RTNL_LINK(DRV_NAME);