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v3.1
  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/netdevice.h>
 12#include <linux/slab.h>
 13#include <linux/ethtool.h>
 14#include <linux/etherdevice.h>
 15#include <linux/u64_stats_sync.h>
 16
 
 17#include <net/dst.h>
 18#include <net/xfrm.h>
 19#include <linux/veth.h>
 
 20
 21#define DRV_NAME	"veth"
 22#define DRV_VERSION	"1.0"
 23
 24#define MIN_MTU 68		/* Min L3 MTU */
 25#define MAX_MTU 65535		/* Max L3 MTU (arbitrary) */
 26
 27struct veth_net_stats {
 28	u64			rx_packets;
 29	u64			tx_packets;
 30	u64			rx_bytes;
 31	u64			tx_bytes;
 32	u64			rx_dropped;
 33	struct u64_stats_sync	syncp;
 34};
 35
 36struct veth_priv {
 37	struct net_device *peer;
 38	struct veth_net_stats __percpu *stats;
 
 39};
 40
 41/*
 42 * ethtool interface
 43 */
 44
 45static struct {
 46	const char string[ETH_GSTRING_LEN];
 47} ethtool_stats_keys[] = {
 48	{ "peer_ifindex" },
 49};
 50
 51static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 52{
 53	cmd->supported		= 0;
 54	cmd->advertising	= 0;
 55	ethtool_cmd_speed_set(cmd, 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
 66static 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
 73static 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
 82static int veth_get_sset_count(struct net_device *dev, int sset)
 83{
 84	switch (sset) {
 85	case ETH_SS_STATS:
 86		return ARRAY_SIZE(ethtool_stats_keys);
 87	default:
 88		return -EOPNOTSUPP;
 89	}
 90}
 91
 92static 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
101static const struct ethtool_ops veth_ethtool_ops = {
102	.get_settings		= veth_get_settings,
103	.get_drvinfo		= veth_get_drvinfo,
104	.get_link		= ethtool_op_get_link,
105	.get_strings		= veth_get_strings,
106	.get_sset_count		= veth_get_sset_count,
107	.get_ethtool_stats	= veth_get_ethtool_stats,
108};
109
110/*
111 * xmit
112 */
113
114static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
115{
116	struct net_device *rcv = NULL;
117	struct veth_priv *priv, *rcv_priv;
118	struct veth_net_stats *stats, *rcv_stats;
119	int length;
120
121	priv = netdev_priv(dev);
122	rcv = priv->peer;
123	rcv_priv = netdev_priv(rcv);
124
125	stats = this_cpu_ptr(priv->stats);
126	rcv_stats = this_cpu_ptr(rcv_priv->stats);
127
128	/* don't change ip_summed == CHECKSUM_PARTIAL, as that
129	   will cause bad checksum on forwarded packets */
130	if (skb->ip_summed == CHECKSUM_NONE &&
131	    rcv->features & NETIF_F_RXCSUM)
132		skb->ip_summed = CHECKSUM_UNNECESSARY;
133
134	length = skb->len;
135	if (dev_forward_skb(rcv, skb) != NET_RX_SUCCESS)
136		goto rx_drop;
137
138	u64_stats_update_begin(&stats->syncp);
139	stats->tx_bytes += length;
140	stats->tx_packets++;
141	u64_stats_update_end(&stats->syncp);
142
143	u64_stats_update_begin(&rcv_stats->syncp);
144	rcv_stats->rx_bytes += length;
145	rcv_stats->rx_packets++;
146	u64_stats_update_end(&rcv_stats->syncp);
147
148	return NETDEV_TX_OK;
 
149
150rx_drop:
151	u64_stats_update_begin(&rcv_stats->syncp);
152	rcv_stats->rx_dropped++;
153	u64_stats_update_end(&rcv_stats->syncp);
 
 
 
 
 
154	return NETDEV_TX_OK;
155}
156
157/*
158 * general routines
159 */
160
161static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev,
162						  struct rtnl_link_stats64 *tot)
163{
164	struct veth_priv *priv = netdev_priv(dev);
165	int cpu;
166
 
 
167	for_each_possible_cpu(cpu) {
168		struct veth_net_stats *stats = per_cpu_ptr(priv->stats, cpu);
169		u64 rx_packets, rx_bytes, rx_dropped;
170		u64 tx_packets, tx_bytes;
171		unsigned int start;
172
173		do {
174			start = u64_stats_fetch_begin_bh(&stats->syncp);
175			rx_packets = stats->rx_packets;
176			tx_packets = stats->tx_packets;
177			rx_bytes = stats->rx_bytes;
178			tx_bytes = stats->tx_bytes;
179			rx_dropped = stats->rx_dropped;
180		} while (u64_stats_fetch_retry_bh(&stats->syncp, start));
181		tot->rx_packets += rx_packets;
182		tot->tx_packets += tx_packets;
183		tot->rx_bytes   += rx_bytes;
184		tot->tx_bytes   += tx_bytes;
185		tot->rx_dropped += rx_dropped;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
186	}
 
187
188	return tot;
189}
190
 
 
 
 
 
191static int veth_open(struct net_device *dev)
192{
193	struct veth_priv *priv;
 
194
195	priv = netdev_priv(dev);
196	if (priv->peer == NULL)
197		return -ENOTCONN;
198
199	if (priv->peer->flags & IFF_UP) {
200		netif_carrier_on(dev);
201		netif_carrier_on(priv->peer);
202	}
203	return 0;
204}
205
206static int veth_close(struct net_device *dev)
207{
208	struct veth_priv *priv = netdev_priv(dev);
 
209
210	netif_carrier_off(dev);
211	netif_carrier_off(priv->peer);
 
212
213	return 0;
214}
215
216static int is_valid_veth_mtu(int new_mtu)
217{
218	return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU;
219}
220
221static int veth_change_mtu(struct net_device *dev, int new_mtu)
222{
223	if (!is_valid_veth_mtu(new_mtu))
224		return -EINVAL;
225	dev->mtu = new_mtu;
226	return 0;
227}
228
229static int veth_dev_init(struct net_device *dev)
230{
231	struct veth_net_stats __percpu *stats;
232	struct veth_priv *priv;
233
234	stats = alloc_percpu(struct veth_net_stats);
235	if (stats == NULL)
236		return -ENOMEM;
237
238	priv = netdev_priv(dev);
239	priv->stats = stats;
240	return 0;
241}
242
243static void veth_dev_free(struct net_device *dev)
244{
245	struct veth_priv *priv;
246
247	priv = netdev_priv(dev);
248	free_percpu(priv->stats);
249	free_netdev(dev);
250}
251
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
252static const struct net_device_ops veth_netdev_ops = {
253	.ndo_init            = veth_dev_init,
254	.ndo_open            = veth_open,
255	.ndo_stop            = veth_close,
256	.ndo_start_xmit      = veth_xmit,
257	.ndo_change_mtu      = veth_change_mtu,
258	.ndo_get_stats64     = veth_get_stats64,
 
259	.ndo_set_mac_address = eth_mac_addr,
 
 
 
 
 
 
260};
261
 
 
 
 
 
 
 
262static void veth_setup(struct net_device *dev)
263{
264	ether_setup(dev);
265
266	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 
 
 
267
268	dev->netdev_ops = &veth_netdev_ops;
269	dev->ethtool_ops = &veth_ethtool_ops;
270	dev->features |= NETIF_F_LLTX;
 
 
 
 
 
 
271	dev->destructor = veth_dev_free;
272
273	dev->hw_features = NETIF_F_NO_CSUM | NETIF_F_SG | NETIF_F_RXCSUM;
 
274}
275
276/*
277 * netlink interface
278 */
279
280static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
281{
282	if (tb[IFLA_ADDRESS]) {
283		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
284			return -EINVAL;
285		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
286			return -EADDRNOTAVAIL;
287	}
288	if (tb[IFLA_MTU]) {
289		if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
290			return -EINVAL;
291	}
292	return 0;
293}
294
295static struct rtnl_link_ops veth_link_ops;
296
297static int veth_newlink(struct net *src_net, struct net_device *dev,
298			 struct nlattr *tb[], struct nlattr *data[])
299{
300	int err;
301	struct net_device *peer;
302	struct veth_priv *priv;
303	char ifname[IFNAMSIZ];
304	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
 
305	struct ifinfomsg *ifmp;
306	struct net *net;
307
308	/*
309	 * create and register peer first
310	 */
311	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
312		struct nlattr *nla_peer;
313
314		nla_peer = data[VETH_INFO_PEER];
315		ifmp = nla_data(nla_peer);
316		err = nla_parse(peer_tb, IFLA_MAX,
317				nla_data(nla_peer) + sizeof(struct ifinfomsg),
318				nla_len(nla_peer) - sizeof(struct ifinfomsg),
319				ifla_policy);
320		if (err < 0)
321			return err;
322
323		err = veth_validate(peer_tb, NULL);
324		if (err < 0)
325			return err;
326
327		tbp = peer_tb;
328	} else {
329		ifmp = NULL;
330		tbp = tb;
331	}
332
333	if (tbp[IFLA_IFNAME])
334		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
335	else
 
336		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
 
 
337
338	net = rtnl_link_get_net(src_net, tbp);
339	if (IS_ERR(net))
340		return PTR_ERR(net);
341
342	peer = rtnl_create_link(src_net, net, ifname, &veth_link_ops, tbp);
 
343	if (IS_ERR(peer)) {
344		put_net(net);
345		return PTR_ERR(peer);
346	}
347
348	if (tbp[IFLA_ADDRESS] == NULL)
349		random_ether_addr(peer->dev_addr);
 
 
 
350
351	err = register_netdevice(peer);
352	put_net(net);
353	net = NULL;
354	if (err < 0)
355		goto err_register_peer;
356
357	netif_carrier_off(peer);
358
359	err = rtnl_configure_link(peer, ifmp);
360	if (err < 0)
361		goto err_configure_peer;
362
363	/*
364	 * register dev last
365	 *
366	 * note, that since we've registered new device the dev's name
367	 * should be re-allocated
368	 */
369
370	if (tb[IFLA_ADDRESS] == NULL)
371		random_ether_addr(dev->dev_addr);
372
373	if (tb[IFLA_IFNAME])
374		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
375	else
376		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
377
378	if (strchr(dev->name, '%')) {
379		err = dev_alloc_name(dev, dev->name);
380		if (err < 0)
381			goto err_alloc_name;
382	}
383
384	err = register_netdevice(dev);
385	if (err < 0)
386		goto err_register_dev;
387
388	netif_carrier_off(dev);
389
390	/*
391	 * tie the deviced together
392	 */
393
394	priv = netdev_priv(dev);
395	priv->peer = peer;
396
397	priv = netdev_priv(peer);
398	priv->peer = dev;
399	return 0;
400
401err_register_dev:
402	/* nothing to do */
403err_alloc_name:
404err_configure_peer:
405	unregister_netdevice(peer);
406	return err;
407
408err_register_peer:
409	free_netdev(peer);
410	return err;
411}
412
413static void veth_dellink(struct net_device *dev, struct list_head *head)
414{
415	struct veth_priv *priv;
416	struct net_device *peer;
417
418	priv = netdev_priv(dev);
419	peer = priv->peer;
420
 
 
 
 
 
421	unregister_netdevice_queue(dev, head);
422	unregister_netdevice_queue(peer, head);
 
 
 
 
 
423}
424
425static const struct nla_policy veth_policy[VETH_INFO_MAX + 1];
 
 
 
 
 
 
 
 
 
 
426
427static struct rtnl_link_ops veth_link_ops = {
428	.kind		= DRV_NAME,
429	.priv_size	= sizeof(struct veth_priv),
430	.setup		= veth_setup,
431	.validate	= veth_validate,
432	.newlink	= veth_newlink,
433	.dellink	= veth_dellink,
434	.policy		= veth_policy,
435	.maxtype	= VETH_INFO_MAX,
 
436};
437
438/*
439 * init/fini
440 */
441
442static __init int veth_init(void)
443{
444	return rtnl_link_register(&veth_link_ops);
445}
446
447static __exit void veth_exit(void)
448{
449	rtnl_link_unregister(&veth_link_ops);
450}
451
452module_init(veth_init);
453module_exit(veth_exit);
454
455MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
456MODULE_LICENSE("GPL v2");
457MODULE_ALIAS_RTNL_LINK(DRV_NAME);
v4.6
  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/netdevice.h>
 12#include <linux/slab.h>
 13#include <linux/ethtool.h>
 14#include <linux/etherdevice.h>
 15#include <linux/u64_stats_sync.h>
 16
 17#include <net/rtnetlink.h>
 18#include <net/dst.h>
 19#include <net/xfrm.h>
 20#include <linux/veth.h>
 21#include <linux/module.h>
 22
 23#define DRV_NAME	"veth"
 24#define DRV_VERSION	"1.0"
 25
 26#define MIN_MTU 68		/* Min L3 MTU */
 27#define MAX_MTU 65535		/* Max L3 MTU (arbitrary) */
 28
 29struct pcpu_vstats {
 30	u64			packets;
 31	u64			bytes;
 
 
 
 32	struct u64_stats_sync	syncp;
 33};
 34
 35struct veth_priv {
 36	struct net_device __rcu	*peer;
 37	atomic64_t		dropped;
 38	unsigned		requested_headroom;
 39};
 40
 41/*
 42 * ethtool interface
 43 */
 44
 45static struct {
 46	const char string[ETH_GSTRING_LEN];
 47} ethtool_stats_keys[] = {
 48	{ "peer_ifindex" },
 49};
 50
 51static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 52{
 53	cmd->supported		= 0;
 54	cmd->advertising	= 0;
 55	ethtool_cmd_speed_set(cmd, 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
 66static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
 67{
 68	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
 69	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
 
 70}
 71
 72static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
 73{
 74	switch(stringset) {
 75	case ETH_SS_STATS:
 76		memcpy(buf, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
 77		break;
 78	}
 79}
 80
 81static int veth_get_sset_count(struct net_device *dev, int sset)
 82{
 83	switch (sset) {
 84	case ETH_SS_STATS:
 85		return ARRAY_SIZE(ethtool_stats_keys);
 86	default:
 87		return -EOPNOTSUPP;
 88	}
 89}
 90
 91static void veth_get_ethtool_stats(struct net_device *dev,
 92		struct ethtool_stats *stats, u64 *data)
 93{
 94	struct veth_priv *priv = netdev_priv(dev);
 95	struct net_device *peer = rtnl_dereference(priv->peer);
 96
 97	data[0] = peer ? peer->ifindex : 0;
 
 98}
 99
100static const struct ethtool_ops veth_ethtool_ops = {
101	.get_settings		= veth_get_settings,
102	.get_drvinfo		= veth_get_drvinfo,
103	.get_link		= ethtool_op_get_link,
104	.get_strings		= veth_get_strings,
105	.get_sset_count		= veth_get_sset_count,
106	.get_ethtool_stats	= veth_get_ethtool_stats,
107};
108
 
 
 
 
109static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
110{
111	struct veth_priv *priv = netdev_priv(dev);
112	struct net_device *rcv;
113	int length = skb->len;
 
 
 
 
 
 
 
 
114
115	rcu_read_lock();
116	rcv = rcu_dereference(priv->peer);
117	if (unlikely(!rcv)) {
118		kfree_skb(skb);
119		goto drop;
120	}
 
 
 
 
 
 
 
 
 
 
 
 
 
121
122	if (likely(dev_forward_skb(rcv, skb) == NET_RX_SUCCESS)) {
123		struct pcpu_vstats *stats = this_cpu_ptr(dev->vstats);
124
125		u64_stats_update_begin(&stats->syncp);
126		stats->bytes += length;
127		stats->packets++;
128		u64_stats_update_end(&stats->syncp);
129	} else {
130drop:
131		atomic64_inc(&priv->dropped);
132	}
133	rcu_read_unlock();
134	return NETDEV_TX_OK;
135}
136
137/*
138 * general routines
139 */
140
141static u64 veth_stats_one(struct pcpu_vstats *result, struct net_device *dev)
 
142{
143	struct veth_priv *priv = netdev_priv(dev);
144	int cpu;
145
146	result->packets = 0;
147	result->bytes = 0;
148	for_each_possible_cpu(cpu) {
149		struct pcpu_vstats *stats = per_cpu_ptr(dev->vstats, cpu);
150		u64 packets, bytes;
 
151		unsigned int start;
152
153		do {
154			start = u64_stats_fetch_begin_irq(&stats->syncp);
155			packets = stats->packets;
156			bytes = stats->bytes;
157		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
158		result->packets += packets;
159		result->bytes += bytes;
160	}
161	return atomic64_read(&priv->dropped);
162}
163
164static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev,
165						  struct rtnl_link_stats64 *tot)
166{
167	struct veth_priv *priv = netdev_priv(dev);
168	struct net_device *peer;
169	struct pcpu_vstats one;
170
171	tot->tx_dropped = veth_stats_one(&one, dev);
172	tot->tx_bytes = one.bytes;
173	tot->tx_packets = one.packets;
174
175	rcu_read_lock();
176	peer = rcu_dereference(priv->peer);
177	if (peer) {
178		tot->rx_dropped = veth_stats_one(&one, peer);
179		tot->rx_bytes = one.bytes;
180		tot->rx_packets = one.packets;
181	}
182	rcu_read_unlock();
183
184	return tot;
185}
186
187/* fake multicast ability */
188static void veth_set_multicast_list(struct net_device *dev)
189{
190}
191
192static int veth_open(struct net_device *dev)
193{
194	struct veth_priv *priv = netdev_priv(dev);
195	struct net_device *peer = rtnl_dereference(priv->peer);
196
197	if (!peer)
 
198		return -ENOTCONN;
199
200	if (peer->flags & IFF_UP) {
201		netif_carrier_on(dev);
202		netif_carrier_on(peer);
203	}
204	return 0;
205}
206
207static int veth_close(struct net_device *dev)
208{
209	struct veth_priv *priv = netdev_priv(dev);
210	struct net_device *peer = rtnl_dereference(priv->peer);
211
212	netif_carrier_off(dev);
213	if (peer)
214		netif_carrier_off(peer);
215
216	return 0;
217}
218
219static int is_valid_veth_mtu(int new_mtu)
220{
221	return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU;
222}
223
224static int veth_change_mtu(struct net_device *dev, int new_mtu)
225{
226	if (!is_valid_veth_mtu(new_mtu))
227		return -EINVAL;
228	dev->mtu = new_mtu;
229	return 0;
230}
231
232static int veth_dev_init(struct net_device *dev)
233{
234	dev->vstats = netdev_alloc_pcpu_stats(struct pcpu_vstats);
235	if (!dev->vstats)
 
 
 
236		return -ENOMEM;
 
 
 
237	return 0;
238}
239
240static void veth_dev_free(struct net_device *dev)
241{
242	free_percpu(dev->vstats);
 
 
 
243	free_netdev(dev);
244}
245
246#ifdef CONFIG_NET_POLL_CONTROLLER
247static void veth_poll_controller(struct net_device *dev)
248{
249	/* veth only receives frames when its peer sends one
250	 * Since it's a synchronous operation, we are guaranteed
251	 * never to have pending data when we poll for it so
252	 * there is nothing to do here.
253	 *
254	 * We need this though so netpoll recognizes us as an interface that
255	 * supports polling, which enables bridge devices in virt setups to
256	 * still use netconsole
257	 */
258}
259#endif	/* CONFIG_NET_POLL_CONTROLLER */
260
261static int veth_get_iflink(const struct net_device *dev)
262{
263	struct veth_priv *priv = netdev_priv(dev);
264	struct net_device *peer;
265	int iflink;
266
267	rcu_read_lock();
268	peer = rcu_dereference(priv->peer);
269	iflink = peer ? peer->ifindex : 0;
270	rcu_read_unlock();
271
272	return iflink;
273}
274
275static void veth_set_rx_headroom(struct net_device *dev, int new_hr)
276{
277	struct veth_priv *peer_priv, *priv = netdev_priv(dev);
278	struct net_device *peer;
279
280	if (new_hr < 0)
281		new_hr = 0;
282
283	rcu_read_lock();
284	peer = rcu_dereference(priv->peer);
285	if (unlikely(!peer))
286		goto out;
287
288	peer_priv = netdev_priv(peer);
289	priv->requested_headroom = new_hr;
290	new_hr = max(priv->requested_headroom, peer_priv->requested_headroom);
291	dev->needed_headroom = new_hr;
292	peer->needed_headroom = new_hr;
293
294out:
295	rcu_read_unlock();
296}
297
298static const struct net_device_ops veth_netdev_ops = {
299	.ndo_init            = veth_dev_init,
300	.ndo_open            = veth_open,
301	.ndo_stop            = veth_close,
302	.ndo_start_xmit      = veth_xmit,
303	.ndo_change_mtu      = veth_change_mtu,
304	.ndo_get_stats64     = veth_get_stats64,
305	.ndo_set_rx_mode     = veth_set_multicast_list,
306	.ndo_set_mac_address = eth_mac_addr,
307#ifdef CONFIG_NET_POLL_CONTROLLER
308	.ndo_poll_controller	= veth_poll_controller,
309#endif
310	.ndo_get_iflink		= veth_get_iflink,
311	.ndo_features_check	= passthru_features_check,
312	.ndo_set_rx_headroom	= veth_set_rx_headroom,
313};
314
315#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_ALL_TSO |    \
316		       NETIF_F_HW_CSUM | NETIF_F_RXCSUM | NETIF_F_HIGHDMA | \
317		       NETIF_F_GSO_GRE | NETIF_F_GSO_UDP_TUNNEL |	    \
318		       NETIF_F_GSO_IPIP | NETIF_F_GSO_SIT | NETIF_F_UFO	|   \
319		       NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
320		       NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
321
322static void veth_setup(struct net_device *dev)
323{
324	ether_setup(dev);
325
326	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
327	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
328	dev->priv_flags |= IFF_NO_QUEUE;
329	dev->priv_flags |= IFF_PHONY_HEADROOM;
330
331	dev->netdev_ops = &veth_netdev_ops;
332	dev->ethtool_ops = &veth_ethtool_ops;
333	dev->features |= NETIF_F_LLTX;
334	dev->features |= VETH_FEATURES;
335	dev->vlan_features = dev->features &
336			     ~(NETIF_F_HW_VLAN_CTAG_TX |
337			       NETIF_F_HW_VLAN_STAG_TX |
338			       NETIF_F_HW_VLAN_CTAG_RX |
339			       NETIF_F_HW_VLAN_STAG_RX);
340	dev->destructor = veth_dev_free;
341
342	dev->hw_features = VETH_FEATURES;
343	dev->hw_enc_features = VETH_FEATURES;
344}
345
346/*
347 * netlink interface
348 */
349
350static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
351{
352	if (tb[IFLA_ADDRESS]) {
353		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
354			return -EINVAL;
355		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
356			return -EADDRNOTAVAIL;
357	}
358	if (tb[IFLA_MTU]) {
359		if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
360			return -EINVAL;
361	}
362	return 0;
363}
364
365static struct rtnl_link_ops veth_link_ops;
366
367static int veth_newlink(struct net *src_net, struct net_device *dev,
368			 struct nlattr *tb[], struct nlattr *data[])
369{
370	int err;
371	struct net_device *peer;
372	struct veth_priv *priv;
373	char ifname[IFNAMSIZ];
374	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
375	unsigned char name_assign_type;
376	struct ifinfomsg *ifmp;
377	struct net *net;
378
379	/*
380	 * create and register peer first
381	 */
382	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
383		struct nlattr *nla_peer;
384
385		nla_peer = data[VETH_INFO_PEER];
386		ifmp = nla_data(nla_peer);
387		err = rtnl_nla_parse_ifla(peer_tb,
388					  nla_data(nla_peer) + sizeof(struct ifinfomsg),
389					  nla_len(nla_peer) - sizeof(struct ifinfomsg));
 
390		if (err < 0)
391			return err;
392
393		err = veth_validate(peer_tb, NULL);
394		if (err < 0)
395			return err;
396
397		tbp = peer_tb;
398	} else {
399		ifmp = NULL;
400		tbp = tb;
401	}
402
403	if (tbp[IFLA_IFNAME]) {
404		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
405		name_assign_type = NET_NAME_USER;
406	} else {
407		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
408		name_assign_type = NET_NAME_ENUM;
409	}
410
411	net = rtnl_link_get_net(src_net, tbp);
412	if (IS_ERR(net))
413		return PTR_ERR(net);
414
415	peer = rtnl_create_link(net, ifname, name_assign_type,
416				&veth_link_ops, tbp);
417	if (IS_ERR(peer)) {
418		put_net(net);
419		return PTR_ERR(peer);
420	}
421
422	if (tbp[IFLA_ADDRESS] == NULL)
423		eth_hw_addr_random(peer);
424
425	if (ifmp && (dev->ifindex != 0))
426		peer->ifindex = ifmp->ifi_index;
427
428	err = register_netdevice(peer);
429	put_net(net);
430	net = NULL;
431	if (err < 0)
432		goto err_register_peer;
433
434	netif_carrier_off(peer);
435
436	err = rtnl_configure_link(peer, ifmp);
437	if (err < 0)
438		goto err_configure_peer;
439
440	/*
441	 * register dev last
442	 *
443	 * note, that since we've registered new device the dev's name
444	 * should be re-allocated
445	 */
446
447	if (tb[IFLA_ADDRESS] == NULL)
448		eth_hw_addr_random(dev);
449
450	if (tb[IFLA_IFNAME])
451		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
452	else
453		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
454
 
 
 
 
 
 
455	err = register_netdevice(dev);
456	if (err < 0)
457		goto err_register_dev;
458
459	netif_carrier_off(dev);
460
461	/*
462	 * tie the deviced together
463	 */
464
465	priv = netdev_priv(dev);
466	rcu_assign_pointer(priv->peer, peer);
467
468	priv = netdev_priv(peer);
469	rcu_assign_pointer(priv->peer, dev);
470	return 0;
471
472err_register_dev:
473	/* nothing to do */
 
474err_configure_peer:
475	unregister_netdevice(peer);
476	return err;
477
478err_register_peer:
479	free_netdev(peer);
480	return err;
481}
482
483static void veth_dellink(struct net_device *dev, struct list_head *head)
484{
485	struct veth_priv *priv;
486	struct net_device *peer;
487
488	priv = netdev_priv(dev);
489	peer = rtnl_dereference(priv->peer);
490
491	/* Note : dellink() is called from default_device_exit_batch(),
492	 * before a rcu_synchronize() point. The devices are guaranteed
493	 * not being freed before one RCU grace period.
494	 */
495	RCU_INIT_POINTER(priv->peer, NULL);
496	unregister_netdevice_queue(dev, head);
497
498	if (peer) {
499		priv = netdev_priv(peer);
500		RCU_INIT_POINTER(priv->peer, NULL);
501		unregister_netdevice_queue(peer, head);
502	}
503}
504
505static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
506	[VETH_INFO_PEER]	= { .len = sizeof(struct ifinfomsg) },
507};
508
509static struct net *veth_get_link_net(const struct net_device *dev)
510{
511	struct veth_priv *priv = netdev_priv(dev);
512	struct net_device *peer = rtnl_dereference(priv->peer);
513
514	return peer ? dev_net(peer) : dev_net(dev);
515}
516
517static struct rtnl_link_ops veth_link_ops = {
518	.kind		= DRV_NAME,
519	.priv_size	= sizeof(struct veth_priv),
520	.setup		= veth_setup,
521	.validate	= veth_validate,
522	.newlink	= veth_newlink,
523	.dellink	= veth_dellink,
524	.policy		= veth_policy,
525	.maxtype	= VETH_INFO_MAX,
526	.get_link_net	= veth_get_link_net,
527};
528
529/*
530 * init/fini
531 */
532
533static __init int veth_init(void)
534{
535	return rtnl_link_register(&veth_link_ops);
536}
537
538static __exit void veth_exit(void)
539{
540	rtnl_link_unregister(&veth_link_ops);
541}
542
543module_init(veth_init);
544module_exit(veth_exit);
545
546MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
547MODULE_LICENSE("GPL v2");
548MODULE_ALIAS_RTNL_LINK(DRV_NAME);