xref: /openbmc/linux/drivers/net/ipvlan/ipvlan_main.c (revision 2eb3ed33e55d003d721d4d1a5e72fe323c12b4c0)
1 /* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.com>
2  *
3  * This program is free software; you can redistribute it and/or
4  * modify it under the terms of the GNU General Public License as
5  * published by the Free Software Foundation; either version 2 of
6  * the License, or (at your option) any later version.
7  *
8  */
9 
10 #include "ipvlan.h"
11 
12 static unsigned int ipvlan_netid __read_mostly;
13 
14 struct ipvlan_netns {
15 	unsigned int ipvl_nf_hook_refcnt;
16 };
17 
18 static const struct nf_hook_ops ipvl_nfops[] = {
19 	{
20 		.hook     = ipvlan_nf_input,
21 		.pf       = NFPROTO_IPV4,
22 		.hooknum  = NF_INET_LOCAL_IN,
23 		.priority = INT_MAX,
24 	},
25 	{
26 		.hook     = ipvlan_nf_input,
27 		.pf       = NFPROTO_IPV6,
28 		.hooknum  = NF_INET_LOCAL_IN,
29 		.priority = INT_MAX,
30 	},
31 };
32 
33 static const struct l3mdev_ops ipvl_l3mdev_ops = {
34 	.l3mdev_l3_rcv = ipvlan_l3_rcv,
35 };
36 
37 static void ipvlan_adjust_mtu(struct ipvl_dev *ipvlan, struct net_device *dev)
38 {
39 	ipvlan->dev->mtu = dev->mtu;
40 }
41 
42 static int ipvlan_register_nf_hook(struct net *net)
43 {
44 	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);
45 	int err = 0;
46 
47 	if (!vnet->ipvl_nf_hook_refcnt) {
48 		err = nf_register_net_hooks(net, ipvl_nfops,
49 					    ARRAY_SIZE(ipvl_nfops));
50 		if (!err)
51 			vnet->ipvl_nf_hook_refcnt = 1;
52 	} else {
53 		vnet->ipvl_nf_hook_refcnt++;
54 	}
55 
56 	return err;
57 }
58 
59 static void ipvlan_unregister_nf_hook(struct net *net)
60 {
61 	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);
62 
63 	if (WARN_ON(!vnet->ipvl_nf_hook_refcnt))
64 		return;
65 
66 	vnet->ipvl_nf_hook_refcnt--;
67 	if (!vnet->ipvl_nf_hook_refcnt)
68 		nf_unregister_net_hooks(net, ipvl_nfops,
69 					ARRAY_SIZE(ipvl_nfops));
70 }
71 
72 static int ipvlan_set_port_mode(struct ipvl_port *port, u16 nval)
73 {
74 	struct ipvl_dev *ipvlan;
75 	struct net_device *mdev = port->dev;
76 	int err = 0;
77 
78 	ASSERT_RTNL();
79 	if (port->mode != nval) {
80 		if (nval == IPVLAN_MODE_L3S) {
81 			/* New mode is L3S */
82 			err = ipvlan_register_nf_hook(read_pnet(&port->pnet));
83 			if (!err) {
84 				mdev->l3mdev_ops = &ipvl_l3mdev_ops;
85 				mdev->priv_flags |= IFF_L3MDEV_MASTER;
86 			} else
87 				return err;
88 		} else if (port->mode == IPVLAN_MODE_L3S) {
89 			/* Old mode was L3S */
90 			mdev->priv_flags &= ~IFF_L3MDEV_MASTER;
91 			ipvlan_unregister_nf_hook(read_pnet(&port->pnet));
92 			mdev->l3mdev_ops = NULL;
93 		}
94 		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
95 			if (nval == IPVLAN_MODE_L3 || nval == IPVLAN_MODE_L3S)
96 				ipvlan->dev->flags |= IFF_NOARP;
97 			else
98 				ipvlan->dev->flags &= ~IFF_NOARP;
99 		}
100 		port->mode = nval;
101 	}
102 	return err;
103 }
104 
105 static int ipvlan_port_create(struct net_device *dev)
106 {
107 	struct ipvl_port *port;
108 	int err, idx;
109 
110 	if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK) {
111 		netdev_err(dev, "Master is either lo or non-ether device\n");
112 		return -EINVAL;
113 	}
114 
115 	if (netdev_is_rx_handler_busy(dev)) {
116 		netdev_err(dev, "Device is already in use.\n");
117 		return -EBUSY;
118 	}
119 
120 	port = kzalloc(sizeof(struct ipvl_port), GFP_KERNEL);
121 	if (!port)
122 		return -ENOMEM;
123 
124 	write_pnet(&port->pnet, dev_net(dev));
125 	port->dev = dev;
126 	port->mode = IPVLAN_MODE_L3;
127 	INIT_LIST_HEAD(&port->ipvlans);
128 	for (idx = 0; idx < IPVLAN_HASH_SIZE; idx++)
129 		INIT_HLIST_HEAD(&port->hlhead[idx]);
130 
131 	skb_queue_head_init(&port->backlog);
132 	INIT_WORK(&port->wq, ipvlan_process_multicast);
133 	ida_init(&port->ida);
134 	port->dev_id_start = 1;
135 
136 	err = netdev_rx_handler_register(dev, ipvlan_handle_frame, port);
137 	if (err)
138 		goto err;
139 
140 	dev->priv_flags |= IFF_IPVLAN_MASTER;
141 	return 0;
142 
143 err:
144 	kfree(port);
145 	return err;
146 }
147 
148 static void ipvlan_port_destroy(struct net_device *dev)
149 {
150 	struct ipvl_port *port = ipvlan_port_get_rtnl(dev);
151 	struct sk_buff *skb;
152 
153 	dev->priv_flags &= ~IFF_IPVLAN_MASTER;
154 	if (port->mode == IPVLAN_MODE_L3S) {
155 		dev->priv_flags &= ~IFF_L3MDEV_MASTER;
156 		ipvlan_unregister_nf_hook(dev_net(dev));
157 		dev->l3mdev_ops = NULL;
158 	}
159 	netdev_rx_handler_unregister(dev);
160 	cancel_work_sync(&port->wq);
161 	while ((skb = __skb_dequeue(&port->backlog)) != NULL) {
162 		if (skb->dev)
163 			dev_put(skb->dev);
164 		kfree_skb(skb);
165 	}
166 	ida_destroy(&port->ida);
167 	kfree(port);
168 }
169 
170 #define IPVLAN_FEATURES \
171 	(NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
172 	 NETIF_F_GSO | NETIF_F_TSO | NETIF_F_GSO_ROBUST | \
173 	 NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \
174 	 NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_STAG_FILTER)
175 
176 #define IPVLAN_STATE_MASK \
177 	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
178 
179 static int ipvlan_init(struct net_device *dev)
180 {
181 	struct ipvl_dev *ipvlan = netdev_priv(dev);
182 	const struct net_device *phy_dev = ipvlan->phy_dev;
183 	struct ipvl_port *port = ipvlan->port;
184 
185 	dev->state = (dev->state & ~IPVLAN_STATE_MASK) |
186 		     (phy_dev->state & IPVLAN_STATE_MASK);
187 	dev->features = phy_dev->features & IPVLAN_FEATURES;
188 	dev->features |= NETIF_F_LLTX;
189 	dev->gso_max_size = phy_dev->gso_max_size;
190 	dev->gso_max_segs = phy_dev->gso_max_segs;
191 	dev->hard_header_len = phy_dev->hard_header_len;
192 
193 	netdev_lockdep_set_classes(dev);
194 
195 	ipvlan->pcpu_stats = netdev_alloc_pcpu_stats(struct ipvl_pcpu_stats);
196 	if (!ipvlan->pcpu_stats)
197 		return -ENOMEM;
198 
199 	port->count += 1;
200 
201 	return 0;
202 }
203 
204 static void ipvlan_uninit(struct net_device *dev)
205 {
206 	struct ipvl_dev *ipvlan = netdev_priv(dev);
207 	struct ipvl_port *port = ipvlan->port;
208 
209 	free_percpu(ipvlan->pcpu_stats);
210 
211 	port->count -= 1;
212 	if (!port->count)
213 		ipvlan_port_destroy(port->dev);
214 }
215 
216 static int ipvlan_open(struct net_device *dev)
217 {
218 	struct ipvl_dev *ipvlan = netdev_priv(dev);
219 	struct net_device *phy_dev = ipvlan->phy_dev;
220 	struct ipvl_addr *addr;
221 
222 	if (ipvlan->port->mode == IPVLAN_MODE_L3 ||
223 	    ipvlan->port->mode == IPVLAN_MODE_L3S)
224 		dev->flags |= IFF_NOARP;
225 	else
226 		dev->flags &= ~IFF_NOARP;
227 
228 	list_for_each_entry(addr, &ipvlan->addrs, anode)
229 		ipvlan_ht_addr_add(ipvlan, addr);
230 
231 	return dev_uc_add(phy_dev, phy_dev->dev_addr);
232 }
233 
234 static int ipvlan_stop(struct net_device *dev)
235 {
236 	struct ipvl_dev *ipvlan = netdev_priv(dev);
237 	struct net_device *phy_dev = ipvlan->phy_dev;
238 	struct ipvl_addr *addr;
239 
240 	dev_uc_unsync(phy_dev, dev);
241 	dev_mc_unsync(phy_dev, dev);
242 
243 	dev_uc_del(phy_dev, phy_dev->dev_addr);
244 
245 	list_for_each_entry(addr, &ipvlan->addrs, anode)
246 		ipvlan_ht_addr_del(addr);
247 
248 	return 0;
249 }
250 
251 static netdev_tx_t ipvlan_start_xmit(struct sk_buff *skb,
252 				     struct net_device *dev)
253 {
254 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
255 	int skblen = skb->len;
256 	int ret;
257 
258 	ret = ipvlan_queue_xmit(skb, dev);
259 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
260 		struct ipvl_pcpu_stats *pcptr;
261 
262 		pcptr = this_cpu_ptr(ipvlan->pcpu_stats);
263 
264 		u64_stats_update_begin(&pcptr->syncp);
265 		pcptr->tx_pkts++;
266 		pcptr->tx_bytes += skblen;
267 		u64_stats_update_end(&pcptr->syncp);
268 	} else {
269 		this_cpu_inc(ipvlan->pcpu_stats->tx_drps);
270 	}
271 	return ret;
272 }
273 
274 static netdev_features_t ipvlan_fix_features(struct net_device *dev,
275 					     netdev_features_t features)
276 {
277 	struct ipvl_dev *ipvlan = netdev_priv(dev);
278 
279 	return features & (ipvlan->sfeatures | ~IPVLAN_FEATURES);
280 }
281 
282 static void ipvlan_change_rx_flags(struct net_device *dev, int change)
283 {
284 	struct ipvl_dev *ipvlan = netdev_priv(dev);
285 	struct net_device *phy_dev = ipvlan->phy_dev;
286 
287 	if (change & IFF_ALLMULTI)
288 		dev_set_allmulti(phy_dev, dev->flags & IFF_ALLMULTI? 1 : -1);
289 }
290 
291 static void ipvlan_set_multicast_mac_filter(struct net_device *dev)
292 {
293 	struct ipvl_dev *ipvlan = netdev_priv(dev);
294 
295 	if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
296 		bitmap_fill(ipvlan->mac_filters, IPVLAN_MAC_FILTER_SIZE);
297 	} else {
298 		struct netdev_hw_addr *ha;
299 		DECLARE_BITMAP(mc_filters, IPVLAN_MAC_FILTER_SIZE);
300 
301 		bitmap_zero(mc_filters, IPVLAN_MAC_FILTER_SIZE);
302 		netdev_for_each_mc_addr(ha, dev)
303 			__set_bit(ipvlan_mac_hash(ha->addr), mc_filters);
304 
305 		/* Turn-on broadcast bit irrespective of address family,
306 		 * since broadcast is deferred to a work-queue, hence no
307 		 * impact on fast-path processing.
308 		 */
309 		__set_bit(ipvlan_mac_hash(dev->broadcast), mc_filters);
310 
311 		bitmap_copy(ipvlan->mac_filters, mc_filters,
312 			    IPVLAN_MAC_FILTER_SIZE);
313 	}
314 	dev_uc_sync(ipvlan->phy_dev, dev);
315 	dev_mc_sync(ipvlan->phy_dev, dev);
316 }
317 
318 static void ipvlan_get_stats64(struct net_device *dev,
319 			       struct rtnl_link_stats64 *s)
320 {
321 	struct ipvl_dev *ipvlan = netdev_priv(dev);
322 
323 	if (ipvlan->pcpu_stats) {
324 		struct ipvl_pcpu_stats *pcptr;
325 		u64 rx_pkts, rx_bytes, rx_mcast, tx_pkts, tx_bytes;
326 		u32 rx_errs = 0, tx_drps = 0;
327 		u32 strt;
328 		int idx;
329 
330 		for_each_possible_cpu(idx) {
331 			pcptr = per_cpu_ptr(ipvlan->pcpu_stats, idx);
332 			do {
333 				strt= u64_stats_fetch_begin_irq(&pcptr->syncp);
334 				rx_pkts = pcptr->rx_pkts;
335 				rx_bytes = pcptr->rx_bytes;
336 				rx_mcast = pcptr->rx_mcast;
337 				tx_pkts = pcptr->tx_pkts;
338 				tx_bytes = pcptr->tx_bytes;
339 			} while (u64_stats_fetch_retry_irq(&pcptr->syncp,
340 							   strt));
341 
342 			s->rx_packets += rx_pkts;
343 			s->rx_bytes += rx_bytes;
344 			s->multicast += rx_mcast;
345 			s->tx_packets += tx_pkts;
346 			s->tx_bytes += tx_bytes;
347 
348 			/* u32 values are updated without syncp protection. */
349 			rx_errs += pcptr->rx_errs;
350 			tx_drps += pcptr->tx_drps;
351 		}
352 		s->rx_errors = rx_errs;
353 		s->rx_dropped = rx_errs;
354 		s->tx_dropped = tx_drps;
355 	}
356 }
357 
358 static int ipvlan_vlan_rx_add_vid(struct net_device *dev, __be16 proto, u16 vid)
359 {
360 	struct ipvl_dev *ipvlan = netdev_priv(dev);
361 	struct net_device *phy_dev = ipvlan->phy_dev;
362 
363 	return vlan_vid_add(phy_dev, proto, vid);
364 }
365 
366 static int ipvlan_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
367 				   u16 vid)
368 {
369 	struct ipvl_dev *ipvlan = netdev_priv(dev);
370 	struct net_device *phy_dev = ipvlan->phy_dev;
371 
372 	vlan_vid_del(phy_dev, proto, vid);
373 	return 0;
374 }
375 
376 static int ipvlan_get_iflink(const struct net_device *dev)
377 {
378 	struct ipvl_dev *ipvlan = netdev_priv(dev);
379 
380 	return ipvlan->phy_dev->ifindex;
381 }
382 
383 static const struct net_device_ops ipvlan_netdev_ops = {
384 	.ndo_init		= ipvlan_init,
385 	.ndo_uninit		= ipvlan_uninit,
386 	.ndo_open		= ipvlan_open,
387 	.ndo_stop		= ipvlan_stop,
388 	.ndo_start_xmit		= ipvlan_start_xmit,
389 	.ndo_fix_features	= ipvlan_fix_features,
390 	.ndo_change_rx_flags	= ipvlan_change_rx_flags,
391 	.ndo_set_rx_mode	= ipvlan_set_multicast_mac_filter,
392 	.ndo_get_stats64	= ipvlan_get_stats64,
393 	.ndo_vlan_rx_add_vid	= ipvlan_vlan_rx_add_vid,
394 	.ndo_vlan_rx_kill_vid	= ipvlan_vlan_rx_kill_vid,
395 	.ndo_get_iflink		= ipvlan_get_iflink,
396 };
397 
398 static int ipvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
399 			      unsigned short type, const void *daddr,
400 			      const void *saddr, unsigned len)
401 {
402 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
403 	struct net_device *phy_dev = ipvlan->phy_dev;
404 
405 	/* TODO Probably use a different field than dev_addr so that the
406 	 * mac-address on the virtual device is portable and can be carried
407 	 * while the packets use the mac-addr on the physical device.
408 	 */
409 	return dev_hard_header(skb, phy_dev, type, daddr,
410 			       saddr ? : phy_dev->dev_addr, len);
411 }
412 
413 static const struct header_ops ipvlan_header_ops = {
414 	.create  	= ipvlan_hard_header,
415 	.parse		= eth_header_parse,
416 	.cache		= eth_header_cache,
417 	.cache_update	= eth_header_cache_update,
418 };
419 
420 static int ipvlan_ethtool_get_link_ksettings(struct net_device *dev,
421 					     struct ethtool_link_ksettings *cmd)
422 {
423 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
424 
425 	return __ethtool_get_link_ksettings(ipvlan->phy_dev, cmd);
426 }
427 
428 static void ipvlan_ethtool_get_drvinfo(struct net_device *dev,
429 				       struct ethtool_drvinfo *drvinfo)
430 {
431 	strlcpy(drvinfo->driver, IPVLAN_DRV, sizeof(drvinfo->driver));
432 	strlcpy(drvinfo->version, IPV_DRV_VER, sizeof(drvinfo->version));
433 }
434 
435 static u32 ipvlan_ethtool_get_msglevel(struct net_device *dev)
436 {
437 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
438 
439 	return ipvlan->msg_enable;
440 }
441 
442 static void ipvlan_ethtool_set_msglevel(struct net_device *dev, u32 value)
443 {
444 	struct ipvl_dev *ipvlan = netdev_priv(dev);
445 
446 	ipvlan->msg_enable = value;
447 }
448 
449 static const struct ethtool_ops ipvlan_ethtool_ops = {
450 	.get_link	= ethtool_op_get_link,
451 	.get_link_ksettings	= ipvlan_ethtool_get_link_ksettings,
452 	.get_drvinfo	= ipvlan_ethtool_get_drvinfo,
453 	.get_msglevel	= ipvlan_ethtool_get_msglevel,
454 	.set_msglevel	= ipvlan_ethtool_set_msglevel,
455 };
456 
457 static int ipvlan_nl_changelink(struct net_device *dev,
458 				struct nlattr *tb[], struct nlattr *data[],
459 				struct netlink_ext_ack *extack)
460 {
461 	struct ipvl_dev *ipvlan = netdev_priv(dev);
462 	struct ipvl_port *port = ipvlan_port_get_rtnl(ipvlan->phy_dev);
463 	int err = 0;
464 
465 	if (!data)
466 		return 0;
467 
468 	if (data[IFLA_IPVLAN_MODE]) {
469 		u16 nmode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
470 
471 		err = ipvlan_set_port_mode(port, nmode);
472 	}
473 
474 	if (!err && data[IFLA_IPVLAN_FLAGS]) {
475 		u16 flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
476 
477 		if (flags & IPVLAN_F_PRIVATE)
478 			ipvlan_mark_private(port);
479 		else
480 			ipvlan_clear_private(port);
481 
482 		if (flags & IPVLAN_F_VEPA)
483 			ipvlan_mark_vepa(port);
484 		else
485 			ipvlan_clear_vepa(port);
486 	}
487 
488 	return err;
489 }
490 
491 static size_t ipvlan_nl_getsize(const struct net_device *dev)
492 {
493 	return (0
494 		+ nla_total_size(2) /* IFLA_IPVLAN_MODE */
495 		+ nla_total_size(2) /* IFLA_IPVLAN_FLAGS */
496 		);
497 }
498 
499 static int ipvlan_nl_validate(struct nlattr *tb[], struct nlattr *data[],
500 			      struct netlink_ext_ack *extack)
501 {
502 	if (!data)
503 		return 0;
504 
505 	if (data[IFLA_IPVLAN_MODE]) {
506 		u16 mode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
507 
508 		if (mode < IPVLAN_MODE_L2 || mode >= IPVLAN_MODE_MAX)
509 			return -EINVAL;
510 	}
511 	if (data[IFLA_IPVLAN_FLAGS]) {
512 		u16 flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
513 
514 		/* Only two bits are used at this moment. */
515 		if (flags & ~(IPVLAN_F_PRIVATE | IPVLAN_F_VEPA))
516 			return -EINVAL;
517 		/* Also both flags can't be active at the same time. */
518 		if ((flags & (IPVLAN_F_PRIVATE | IPVLAN_F_VEPA)) ==
519 		    (IPVLAN_F_PRIVATE | IPVLAN_F_VEPA))
520 			return -EINVAL;
521 	}
522 
523 	return 0;
524 }
525 
526 static int ipvlan_nl_fillinfo(struct sk_buff *skb,
527 			      const struct net_device *dev)
528 {
529 	struct ipvl_dev *ipvlan = netdev_priv(dev);
530 	struct ipvl_port *port = ipvlan_port_get_rtnl(ipvlan->phy_dev);
531 	int ret = -EINVAL;
532 
533 	if (!port)
534 		goto err;
535 
536 	ret = -EMSGSIZE;
537 	if (nla_put_u16(skb, IFLA_IPVLAN_MODE, port->mode))
538 		goto err;
539 	if (nla_put_u16(skb, IFLA_IPVLAN_FLAGS, port->flags))
540 		goto err;
541 
542 	return 0;
543 
544 err:
545 	return ret;
546 }
547 
548 int ipvlan_link_new(struct net *src_net, struct net_device *dev,
549 		    struct nlattr *tb[], struct nlattr *data[],
550 		    struct netlink_ext_ack *extack)
551 {
552 	struct ipvl_dev *ipvlan = netdev_priv(dev);
553 	struct ipvl_port *port;
554 	struct net_device *phy_dev;
555 	int err;
556 	u16 mode = IPVLAN_MODE_L3;
557 	bool create = false;
558 
559 	if (!tb[IFLA_LINK])
560 		return -EINVAL;
561 
562 	phy_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
563 	if (!phy_dev)
564 		return -ENODEV;
565 
566 	if (netif_is_ipvlan(phy_dev)) {
567 		struct ipvl_dev *tmp = netdev_priv(phy_dev);
568 
569 		phy_dev = tmp->phy_dev;
570 	} else if (!netif_is_ipvlan_port(phy_dev)) {
571 		err = ipvlan_port_create(phy_dev);
572 		if (err < 0)
573 			return err;
574 		create = true;
575 	}
576 
577 	if (data && data[IFLA_IPVLAN_MODE])
578 		mode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
579 
580 	port = ipvlan_port_get_rtnl(phy_dev);
581 	ipvlan->phy_dev = phy_dev;
582 	ipvlan->dev = dev;
583 	ipvlan->port = port;
584 	ipvlan->sfeatures = IPVLAN_FEATURES;
585 	ipvlan_adjust_mtu(ipvlan, phy_dev);
586 	INIT_LIST_HEAD(&ipvlan->addrs);
587 
588 	/* Flags are per port and latest update overrides. User has
589 	 * to be consistent in setting it just like the mode attribute.
590 	 */
591 	if (data && data[IFLA_IPVLAN_FLAGS])
592 		ipvlan->port->flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
593 
594 	/* If the port-id base is at the MAX value, then wrap it around and
595 	 * begin from 0x1 again. This may be due to a busy system where lots
596 	 * of slaves are getting created and deleted.
597 	 */
598 	if (port->dev_id_start == 0xFFFE)
599 		port->dev_id_start = 0x1;
600 
601 	/* Since L2 address is shared among all IPvlan slaves including
602 	 * master, use unique 16 bit dev-ids to diffentiate among them.
603 	 * Assign IDs between 0x1 and 0xFFFE (used by the master) to each
604 	 * slave link [see addrconf_ifid_eui48()].
605 	 */
606 	err = ida_simple_get(&port->ida, port->dev_id_start, 0xFFFE,
607 			     GFP_KERNEL);
608 	if (err < 0)
609 		err = ida_simple_get(&port->ida, 0x1, port->dev_id_start,
610 				     GFP_KERNEL);
611 	if (err < 0)
612 		goto destroy_ipvlan_port;
613 	dev->dev_id = err;
614 	/* Increment id-base to the next slot for the future assignment */
615 	port->dev_id_start = err + 1;
616 
617 	/* TODO Probably put random address here to be presented to the
618 	 * world but keep using the physical-dev address for the outgoing
619 	 * packets.
620 	 */
621 	memcpy(dev->dev_addr, phy_dev->dev_addr, ETH_ALEN);
622 
623 	dev->priv_flags |= IFF_IPVLAN_SLAVE;
624 
625 	err = register_netdevice(dev);
626 	if (err < 0)
627 		goto remove_ida;
628 
629 	err = netdev_upper_dev_link(phy_dev, dev, extack);
630 	if (err) {
631 		goto unregister_netdev;
632 	}
633 	err = ipvlan_set_port_mode(port, mode);
634 	if (err) {
635 		goto unlink_netdev;
636 	}
637 
638 	list_add_tail_rcu(&ipvlan->pnode, &port->ipvlans);
639 	netif_stacked_transfer_operstate(phy_dev, dev);
640 	return 0;
641 
642 unlink_netdev:
643 	netdev_upper_dev_unlink(phy_dev, dev);
644 unregister_netdev:
645 	unregister_netdevice(dev);
646 remove_ida:
647 	ida_simple_remove(&port->ida, dev->dev_id);
648 destroy_ipvlan_port:
649 	if (create)
650 		ipvlan_port_destroy(phy_dev);
651 	return err;
652 }
653 EXPORT_SYMBOL_GPL(ipvlan_link_new);
654 
655 void ipvlan_link_delete(struct net_device *dev, struct list_head *head)
656 {
657 	struct ipvl_dev *ipvlan = netdev_priv(dev);
658 	struct ipvl_addr *addr, *next;
659 
660 	list_for_each_entry_safe(addr, next, &ipvlan->addrs, anode) {
661 		ipvlan_ht_addr_del(addr);
662 		list_del(&addr->anode);
663 		kfree_rcu(addr, rcu);
664 	}
665 
666 	ida_simple_remove(&ipvlan->port->ida, dev->dev_id);
667 	list_del_rcu(&ipvlan->pnode);
668 	unregister_netdevice_queue(dev, head);
669 	netdev_upper_dev_unlink(ipvlan->phy_dev, dev);
670 }
671 EXPORT_SYMBOL_GPL(ipvlan_link_delete);
672 
673 void ipvlan_link_setup(struct net_device *dev)
674 {
675 	ether_setup(dev);
676 
677 	dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
678 	dev->priv_flags |= IFF_UNICAST_FLT | IFF_NO_QUEUE;
679 	dev->netdev_ops = &ipvlan_netdev_ops;
680 	dev->needs_free_netdev = true;
681 	dev->header_ops = &ipvlan_header_ops;
682 	dev->ethtool_ops = &ipvlan_ethtool_ops;
683 }
684 EXPORT_SYMBOL_GPL(ipvlan_link_setup);
685 
686 static const struct nla_policy ipvlan_nl_policy[IFLA_IPVLAN_MAX + 1] =
687 {
688 	[IFLA_IPVLAN_MODE] = { .type = NLA_U16 },
689 	[IFLA_IPVLAN_FLAGS] = { .type = NLA_U16 },
690 };
691 
692 static struct rtnl_link_ops ipvlan_link_ops = {
693 	.kind		= "ipvlan",
694 	.priv_size	= sizeof(struct ipvl_dev),
695 
696 	.setup		= ipvlan_link_setup,
697 	.newlink	= ipvlan_link_new,
698 	.dellink	= ipvlan_link_delete,
699 };
700 
701 int ipvlan_link_register(struct rtnl_link_ops *ops)
702 {
703 	ops->get_size	= ipvlan_nl_getsize;
704 	ops->policy	= ipvlan_nl_policy;
705 	ops->validate	= ipvlan_nl_validate;
706 	ops->fill_info	= ipvlan_nl_fillinfo;
707 	ops->changelink = ipvlan_nl_changelink;
708 	ops->maxtype	= IFLA_IPVLAN_MAX;
709 	return rtnl_link_register(ops);
710 }
711 EXPORT_SYMBOL_GPL(ipvlan_link_register);
712 
713 static int ipvlan_device_event(struct notifier_block *unused,
714 			       unsigned long event, void *ptr)
715 {
716 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
717 	struct ipvl_dev *ipvlan, *next;
718 	struct ipvl_port *port;
719 	LIST_HEAD(lst_kill);
720 
721 	if (!netif_is_ipvlan_port(dev))
722 		return NOTIFY_DONE;
723 
724 	port = ipvlan_port_get_rtnl(dev);
725 
726 	switch (event) {
727 	case NETDEV_CHANGE:
728 		list_for_each_entry(ipvlan, &port->ipvlans, pnode)
729 			netif_stacked_transfer_operstate(ipvlan->phy_dev,
730 							 ipvlan->dev);
731 		break;
732 
733 	case NETDEV_REGISTER: {
734 		struct net *oldnet, *newnet = dev_net(dev);
735 		struct ipvlan_netns *old_vnet;
736 
737 		oldnet = read_pnet(&port->pnet);
738 		if (net_eq(newnet, oldnet))
739 			break;
740 
741 		write_pnet(&port->pnet, newnet);
742 
743 		old_vnet = net_generic(oldnet, ipvlan_netid);
744 		if (!old_vnet->ipvl_nf_hook_refcnt)
745 			break;
746 
747 		ipvlan_register_nf_hook(newnet);
748 		ipvlan_unregister_nf_hook(oldnet);
749 		break;
750 	}
751 	case NETDEV_UNREGISTER:
752 		if (dev->reg_state != NETREG_UNREGISTERING)
753 			break;
754 
755 		list_for_each_entry_safe(ipvlan, next, &port->ipvlans,
756 					 pnode)
757 			ipvlan->dev->rtnl_link_ops->dellink(ipvlan->dev,
758 							    &lst_kill);
759 		unregister_netdevice_many(&lst_kill);
760 		break;
761 
762 	case NETDEV_FEAT_CHANGE:
763 		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
764 			ipvlan->dev->features = dev->features & IPVLAN_FEATURES;
765 			ipvlan->dev->gso_max_size = dev->gso_max_size;
766 			ipvlan->dev->gso_max_segs = dev->gso_max_segs;
767 			netdev_features_change(ipvlan->dev);
768 		}
769 		break;
770 
771 	case NETDEV_CHANGEMTU:
772 		list_for_each_entry(ipvlan, &port->ipvlans, pnode)
773 			ipvlan_adjust_mtu(ipvlan, dev);
774 		break;
775 
776 	case NETDEV_CHANGEADDR:
777 		list_for_each_entry(ipvlan, &port->ipvlans, pnode)
778 			ether_addr_copy(ipvlan->dev->dev_addr, dev->dev_addr);
779 		break;
780 
781 	case NETDEV_PRE_TYPE_CHANGE:
782 		/* Forbid underlying device to change its type. */
783 		return NOTIFY_BAD;
784 	}
785 	return NOTIFY_DONE;
786 }
787 
788 static int ipvlan_add_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
789 {
790 	struct ipvl_addr *addr;
791 
792 	addr = kzalloc(sizeof(struct ipvl_addr), GFP_ATOMIC);
793 	if (!addr)
794 		return -ENOMEM;
795 
796 	addr->master = ipvlan;
797 	if (is_v6) {
798 		memcpy(&addr->ip6addr, iaddr, sizeof(struct in6_addr));
799 		addr->atype = IPVL_IPV6;
800 	} else {
801 		memcpy(&addr->ip4addr, iaddr, sizeof(struct in_addr));
802 		addr->atype = IPVL_IPV4;
803 	}
804 	list_add_tail(&addr->anode, &ipvlan->addrs);
805 
806 	/* If the interface is not up, the address will be added to the hash
807 	 * list by ipvlan_open.
808 	 */
809 	if (netif_running(ipvlan->dev))
810 		ipvlan_ht_addr_add(ipvlan, addr);
811 
812 	return 0;
813 }
814 
815 static void ipvlan_del_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
816 {
817 	struct ipvl_addr *addr;
818 
819 	addr = ipvlan_find_addr(ipvlan, iaddr, is_v6);
820 	if (!addr)
821 		return;
822 
823 	ipvlan_ht_addr_del(addr);
824 	list_del(&addr->anode);
825 	kfree_rcu(addr, rcu);
826 
827 	return;
828 }
829 
830 static int ipvlan_add_addr6(struct ipvl_dev *ipvlan, struct in6_addr *ip6_addr)
831 {
832 	if (ipvlan_addr_busy(ipvlan->port, ip6_addr, true)) {
833 		netif_err(ipvlan, ifup, ipvlan->dev,
834 			  "Failed to add IPv6=%pI6c addr for %s intf\n",
835 			  ip6_addr, ipvlan->dev->name);
836 		return -EINVAL;
837 	}
838 
839 	return ipvlan_add_addr(ipvlan, ip6_addr, true);
840 }
841 
842 static void ipvlan_del_addr6(struct ipvl_dev *ipvlan, struct in6_addr *ip6_addr)
843 {
844 	return ipvlan_del_addr(ipvlan, ip6_addr, true);
845 }
846 
847 static int ipvlan_addr6_event(struct notifier_block *unused,
848 			      unsigned long event, void *ptr)
849 {
850 	struct inet6_ifaddr *if6 = (struct inet6_ifaddr *)ptr;
851 	struct net_device *dev = (struct net_device *)if6->idev->dev;
852 	struct ipvl_dev *ipvlan = netdev_priv(dev);
853 
854 	if (!netif_is_ipvlan(dev))
855 		return NOTIFY_DONE;
856 
857 	if (!ipvlan || !ipvlan->port)
858 		return NOTIFY_DONE;
859 
860 	switch (event) {
861 	case NETDEV_UP:
862 		if (ipvlan_add_addr6(ipvlan, &if6->addr))
863 			return NOTIFY_BAD;
864 		break;
865 
866 	case NETDEV_DOWN:
867 		ipvlan_del_addr6(ipvlan, &if6->addr);
868 		break;
869 	}
870 
871 	return NOTIFY_OK;
872 }
873 
874 static int ipvlan_addr6_validator_event(struct notifier_block *unused,
875 					unsigned long event, void *ptr)
876 {
877 	struct in6_validator_info *i6vi = (struct in6_validator_info *)ptr;
878 	struct net_device *dev = (struct net_device *)i6vi->i6vi_dev->dev;
879 	struct ipvl_dev *ipvlan = netdev_priv(dev);
880 
881 	/* FIXME IPv6 autoconf calls us from bh without RTNL */
882 	if (in_softirq())
883 		return NOTIFY_DONE;
884 
885 	if (!netif_is_ipvlan(dev))
886 		return NOTIFY_DONE;
887 
888 	if (!ipvlan || !ipvlan->port)
889 		return NOTIFY_DONE;
890 
891 	switch (event) {
892 	case NETDEV_UP:
893 		if (ipvlan_addr_busy(ipvlan->port, &i6vi->i6vi_addr, true)) {
894 			NL_SET_ERR_MSG(i6vi->extack,
895 				       "Address already assigned to an ipvlan device");
896 			return notifier_from_errno(-EADDRINUSE);
897 		}
898 		break;
899 	}
900 
901 	return NOTIFY_OK;
902 }
903 
904 static int ipvlan_add_addr4(struct ipvl_dev *ipvlan, struct in_addr *ip4_addr)
905 {
906 	if (ipvlan_addr_busy(ipvlan->port, ip4_addr, false)) {
907 		netif_err(ipvlan, ifup, ipvlan->dev,
908 			  "Failed to add IPv4=%pI4 on %s intf.\n",
909 			  ip4_addr, ipvlan->dev->name);
910 		return -EINVAL;
911 	}
912 
913 	return ipvlan_add_addr(ipvlan, ip4_addr, false);
914 }
915 
916 static void ipvlan_del_addr4(struct ipvl_dev *ipvlan, struct in_addr *ip4_addr)
917 {
918 	return ipvlan_del_addr(ipvlan, ip4_addr, false);
919 }
920 
921 static int ipvlan_addr4_event(struct notifier_block *unused,
922 			      unsigned long event, void *ptr)
923 {
924 	struct in_ifaddr *if4 = (struct in_ifaddr *)ptr;
925 	struct net_device *dev = (struct net_device *)if4->ifa_dev->dev;
926 	struct ipvl_dev *ipvlan = netdev_priv(dev);
927 	struct in_addr ip4_addr;
928 
929 	if (!netif_is_ipvlan(dev))
930 		return NOTIFY_DONE;
931 
932 	if (!ipvlan || !ipvlan->port)
933 		return NOTIFY_DONE;
934 
935 	switch (event) {
936 	case NETDEV_UP:
937 		ip4_addr.s_addr = if4->ifa_address;
938 		if (ipvlan_add_addr4(ipvlan, &ip4_addr))
939 			return NOTIFY_BAD;
940 		break;
941 
942 	case NETDEV_DOWN:
943 		ip4_addr.s_addr = if4->ifa_address;
944 		ipvlan_del_addr4(ipvlan, &ip4_addr);
945 		break;
946 	}
947 
948 	return NOTIFY_OK;
949 }
950 
951 static int ipvlan_addr4_validator_event(struct notifier_block *unused,
952 					unsigned long event, void *ptr)
953 {
954 	struct in_validator_info *ivi = (struct in_validator_info *)ptr;
955 	struct net_device *dev = (struct net_device *)ivi->ivi_dev->dev;
956 	struct ipvl_dev *ipvlan = netdev_priv(dev);
957 
958 	if (!netif_is_ipvlan(dev))
959 		return NOTIFY_DONE;
960 
961 	if (!ipvlan || !ipvlan->port)
962 		return NOTIFY_DONE;
963 
964 	switch (event) {
965 	case NETDEV_UP:
966 		if (ipvlan_addr_busy(ipvlan->port, &ivi->ivi_addr, false)) {
967 			NL_SET_ERR_MSG(ivi->extack,
968 				       "Address already assigned to an ipvlan device");
969 			return notifier_from_errno(-EADDRINUSE);
970 		}
971 		break;
972 	}
973 
974 	return NOTIFY_OK;
975 }
976 
977 static struct notifier_block ipvlan_addr4_notifier_block __read_mostly = {
978 	.notifier_call = ipvlan_addr4_event,
979 };
980 
981 static struct notifier_block ipvlan_addr4_vtor_notifier_block __read_mostly = {
982 	.notifier_call = ipvlan_addr4_validator_event,
983 };
984 
985 static struct notifier_block ipvlan_notifier_block __read_mostly = {
986 	.notifier_call = ipvlan_device_event,
987 };
988 
989 static struct notifier_block ipvlan_addr6_notifier_block __read_mostly = {
990 	.notifier_call = ipvlan_addr6_event,
991 };
992 
993 static struct notifier_block ipvlan_addr6_vtor_notifier_block __read_mostly = {
994 	.notifier_call = ipvlan_addr6_validator_event,
995 };
996 
997 static void ipvlan_ns_exit(struct net *net)
998 {
999 	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);
1000 
1001 	if (WARN_ON_ONCE(vnet->ipvl_nf_hook_refcnt)) {
1002 		vnet->ipvl_nf_hook_refcnt = 0;
1003 		nf_unregister_net_hooks(net, ipvl_nfops,
1004 					ARRAY_SIZE(ipvl_nfops));
1005 	}
1006 }
1007 
1008 static struct pernet_operations ipvlan_net_ops = {
1009 	.id = &ipvlan_netid,
1010 	.size = sizeof(struct ipvlan_netns),
1011 	.exit = ipvlan_ns_exit,
1012 };
1013 
1014 static int __init ipvlan_init_module(void)
1015 {
1016 	int err;
1017 
1018 	ipvlan_init_secret();
1019 	register_netdevice_notifier(&ipvlan_notifier_block);
1020 	register_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1021 	register_inet6addr_validator_notifier(
1022 	    &ipvlan_addr6_vtor_notifier_block);
1023 	register_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1024 	register_inetaddr_validator_notifier(&ipvlan_addr4_vtor_notifier_block);
1025 
1026 	err = register_pernet_subsys(&ipvlan_net_ops);
1027 	if (err < 0)
1028 		goto error;
1029 
1030 	err = ipvlan_link_register(&ipvlan_link_ops);
1031 	if (err < 0) {
1032 		unregister_pernet_subsys(&ipvlan_net_ops);
1033 		goto error;
1034 	}
1035 
1036 	return 0;
1037 error:
1038 	unregister_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1039 	unregister_inetaddr_validator_notifier(
1040 	    &ipvlan_addr4_vtor_notifier_block);
1041 	unregister_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1042 	unregister_inet6addr_validator_notifier(
1043 	    &ipvlan_addr6_vtor_notifier_block);
1044 	unregister_netdevice_notifier(&ipvlan_notifier_block);
1045 	return err;
1046 }
1047 
1048 static void __exit ipvlan_cleanup_module(void)
1049 {
1050 	rtnl_link_unregister(&ipvlan_link_ops);
1051 	unregister_pernet_subsys(&ipvlan_net_ops);
1052 	unregister_netdevice_notifier(&ipvlan_notifier_block);
1053 	unregister_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1054 	unregister_inetaddr_validator_notifier(
1055 	    &ipvlan_addr4_vtor_notifier_block);
1056 	unregister_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1057 	unregister_inet6addr_validator_notifier(
1058 	    &ipvlan_addr6_vtor_notifier_block);
1059 }
1060 
1061 module_init(ipvlan_init_module);
1062 module_exit(ipvlan_cleanup_module);
1063 
1064 MODULE_LICENSE("GPL");
1065 MODULE_AUTHOR("Mahesh Bandewar <maheshb@google.com>");
1066 MODULE_DESCRIPTION("Driver for L3 (IPv6/IPv4) based VLANs");
1067 MODULE_ALIAS_RTNL_LINK("ipvlan");
1068