summaryrefslogtreecommitdiffstats
path: root/net/batman-adv/hard-interface.c
blob: fbda6b54baffccf798375cb8add49bb179738386 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
/* Copyright (C) 2007-2014 B.A.T.M.A.N. contributors:
 *
 * Marek Lindner, Simon Wunderlich
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License 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, see <http://www.gnu.org/licenses/>.
 */

#include "main.h"
#include "distributed-arp-table.h"
#include "hard-interface.h"
#include "soft-interface.h"
#include "send.h"
#include "translation-table.h"
#include "routing.h"
#include "sysfs.h"
#include "debugfs.h"
#include "originator.h"
#include "hash.h"
#include "bridge_loop_avoidance.h"
#include "gateway_client.h"

#include <linux/if_arp.h>
#include <linux/if_ether.h>

void batadv_hardif_free_rcu(struct rcu_head *rcu)
{
	struct batadv_hard_iface *hard_iface;

	hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
	dev_put(hard_iface->net_dev);
	kfree(hard_iface);
}

struct batadv_hard_iface *
batadv_hardif_get_by_netdev(const struct net_device *net_dev)
{
	struct batadv_hard_iface *hard_iface;

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
		if (hard_iface->net_dev == net_dev &&
		    atomic_inc_not_zero(&hard_iface->refcount))
			goto out;
	}

	hard_iface = NULL;

out:
	rcu_read_unlock();
	return hard_iface;
}

/**
 * batadv_is_on_batman_iface - check if a device is a batman iface descendant
 * @net_dev: the device to check
 *
 * If the user creates any virtual device on top of a batman-adv interface, it
 * is important to prevent this new interface to be used to create a new mesh
 * network (this behaviour would lead to a batman-over-batman configuration).
 * This function recursively checks all the fathers of the device passed as
 * argument looking for a batman-adv soft interface.
 *
 * Returns true if the device is descendant of a batman-adv mesh interface (or
 * if it is a batman-adv interface itself), false otherwise
 */
static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
{
	struct net_device *parent_dev;
	bool ret;

	/* check if this is a batman-adv mesh interface */
	if (batadv_softif_is_valid(net_dev))
		return true;

	/* no more parents..stop recursion */
	if (net_dev->iflink == 0 || net_dev->iflink == net_dev->ifindex)
		return false;

	/* recurse over the parent device */
	parent_dev = __dev_get_by_index(&init_net, net_dev->iflink);
	/* if we got a NULL parent_dev there is something broken.. */
	if (WARN(!parent_dev, "Cannot find parent device"))
		return false;

	ret = batadv_is_on_batman_iface(parent_dev);

	return ret;
}

static int batadv_is_valid_iface(const struct net_device *net_dev)
{
	if (net_dev->flags & IFF_LOOPBACK)
		return 0;

	if (net_dev->type != ARPHRD_ETHER)
		return 0;

	if (net_dev->addr_len != ETH_ALEN)
		return 0;

	/* no batman over batman */
	if (batadv_is_on_batman_iface(net_dev))
		return 0;

	return 1;
}

/**
 * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
 *  interface
 * @net_device: the device to check
 *
 * Returns true if the net device is a 802.11 wireless device, false otherwise.
 */
bool batadv_is_wifi_netdev(struct net_device *net_device)
{
	if (!net_device)
		return false;

#ifdef CONFIG_WIRELESS_EXT
	/* pre-cfg80211 drivers have to implement WEXT, so it is possible to
	 * check for wireless_handlers != NULL
	 */
	if (net_device->wireless_handlers)
		return true;
#endif

	/* cfg80211 drivers have to set ieee80211_ptr */
	if (net_device->ieee80211_ptr)
		return true;

	return false;
}

static struct batadv_hard_iface *
batadv_hardif_get_active(const struct net_device *soft_iface)
{
	struct batadv_hard_iface *hard_iface;

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
		if (hard_iface->soft_iface != soft_iface)
			continue;

		if (hard_iface->if_status == BATADV_IF_ACTIVE &&
		    atomic_inc_not_zero(&hard_iface->refcount))
			goto out;
	}

	hard_iface = NULL;

out:
	rcu_read_unlock();
	return hard_iface;
}

static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
					  struct batadv_hard_iface *oldif)
{
	struct batadv_hard_iface *primary_if;

	primary_if = batadv_primary_if_get_selected(bat_priv);
	if (!primary_if)
		goto out;

	batadv_dat_init_own_addr(bat_priv, primary_if);
	batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
}

static void batadv_primary_if_select(struct batadv_priv *bat_priv,
				     struct batadv_hard_iface *new_hard_iface)
{
	struct batadv_hard_iface *curr_hard_iface;

	ASSERT_RTNL();

	if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
		new_hard_iface = NULL;

	curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
	rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);

	if (!new_hard_iface)
		goto out;

	bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
	batadv_primary_if_update_addr(bat_priv, curr_hard_iface);

out:
	if (curr_hard_iface)
		batadv_hardif_free_ref(curr_hard_iface);
}

static bool
batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
{
	if (hard_iface->net_dev->flags & IFF_UP)
		return true;

	return false;
}

static void batadv_check_known_mac_addr(const struct net_device *net_dev)
{
	const struct batadv_hard_iface *hard_iface;

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
		if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
		    (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
			continue;

		if (hard_iface->net_dev == net_dev)
			continue;

		if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
					net_dev->dev_addr))
			continue;

		pr_warn("The newly added mac address (%pM) already exists on: %s\n",
			net_dev->dev_addr, hard_iface->net_dev->name);
		pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
	}
	rcu_read_unlock();
}

int batadv_hardif_min_mtu(struct net_device *soft_iface)
{
	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
	const struct batadv_hard_iface *hard_iface;
	int min_mtu = INT_MAX;

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
		if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
		    (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
			continue;

		if (hard_iface->soft_iface != soft_iface)
			continue;

		min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
	}
	rcu_read_unlock();

	if (atomic_read(&bat_priv->fragmentation) == 0)
		goto out;

	/* with fragmentation enabled the maximum size of internally generated
	 * packets such as translation table exchanges or tvlv containers, etc
	 * has to be calculated
	 */
	min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
	min_mtu -= sizeof(struct batadv_frag_packet);
	min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;

out:
	/* report to the other components the maximum amount of bytes that
	 * batman-adv can send over the wire (without considering the payload
	 * overhead). For example, this value is used by TT to compute the
	 * maximum local table table size
	 */
	atomic_set(&bat_priv->packet_size_max, min_mtu);

	/* the real soft-interface MTU is computed by removing the payload
	 * overhead from the maximum amount of bytes that was just computed.
	 *
	 * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
	 */
	return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
}

/* adjusts the MTU if a new interface with a smaller MTU appeared. */
void batadv_update_min_mtu(struct net_device *soft_iface)
{
	soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);

	/* Check if the local translate table should be cleaned up to match a
	 * new (and smaller) MTU.
	 */
	batadv_tt_local_resize_to_mtu(soft_iface);
}

static void
batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
{
	struct batadv_priv *bat_priv;
	struct batadv_hard_iface *primary_if = NULL;

	if (hard_iface->if_status != BATADV_IF_INACTIVE)
		goto out;

	bat_priv = netdev_priv(hard_iface->soft_iface);

	bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
	hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;

	/* the first active interface becomes our primary interface or
	 * the next active interface after the old primary interface was removed
	 */
	primary_if = batadv_primary_if_get_selected(bat_priv);
	if (!primary_if)
		batadv_primary_if_select(bat_priv, hard_iface);

	batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
		    hard_iface->net_dev->name);

	batadv_update_min_mtu(hard_iface->soft_iface);

out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
}

static void
batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
{
	if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
	    (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
		return;

	hard_iface->if_status = BATADV_IF_INACTIVE;

	batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
		    hard_iface->net_dev->name);

	batadv_update_min_mtu(hard_iface->soft_iface);
}

/**
 * batadv_master_del_slave - remove hard_iface from the current master interface
 * @slave: the interface enslaved in another master
 * @master: the master from which slave has to be removed
 *
 * Invoke ndo_del_slave on master passing slave as argument. In this way slave
 * is free'd and master can correctly change its internal state.
 * Return 0 on success, a negative value representing the error otherwise
 */
static int batadv_master_del_slave(struct batadv_hard_iface *slave,
				   struct net_device *master)
{
	int ret;

	if (!master)
		return 0;

	ret = -EBUSY;
	if (master->netdev_ops->ndo_del_slave)
		ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);

	return ret;
}

int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
				   const char *iface_name)
{
	struct batadv_priv *bat_priv;
	struct net_device *soft_iface, *master;
	__be16 ethertype = htons(ETH_P_BATMAN);
	int max_header_len = batadv_max_header_len();
	int ret;

	if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
		goto out;

	if (!atomic_inc_not_zero(&hard_iface->refcount))
		goto out;

	soft_iface = dev_get_by_name(&init_net, iface_name);

	if (!soft_iface) {
		soft_iface = batadv_softif_create(iface_name);

		if (!soft_iface) {
			ret = -ENOMEM;
			goto err;
		}

		/* dev_get_by_name() increases the reference counter for us */
		dev_hold(soft_iface);
	}

	if (!batadv_softif_is_valid(soft_iface)) {
		pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
		       soft_iface->name);
		ret = -EINVAL;
		goto err_dev;
	}

	/* check if the interface is enslaved in another virtual one and
	 * in that case unlink it first
	 */
	master = netdev_master_upper_dev_get(hard_iface->net_dev);
	ret = batadv_master_del_slave(hard_iface, master);
	if (ret)
		goto err_dev;

	hard_iface->soft_iface = soft_iface;
	bat_priv = netdev_priv(hard_iface->soft_iface);

	ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
	if (ret)
		goto err_dev;

	ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
	if (ret < 0)
		goto err_upper;

	hard_iface->if_num = bat_priv->num_ifaces;
	bat_priv->num_ifaces++;
	hard_iface->if_status = BATADV_IF_INACTIVE;
	ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
	if (ret < 0) {
		bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
		bat_priv->num_ifaces--;
		hard_iface->if_status = BATADV_IF_NOT_IN_USE;
		goto err_upper;
	}

	hard_iface->batman_adv_ptype.type = ethertype;
	hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
	hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
	dev_add_pack(&hard_iface->batman_adv_ptype);

	batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
		    hard_iface->net_dev->name);

	if (atomic_read(&bat_priv->fragmentation) &&
	    hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
		batadv_info(hard_iface->soft_iface,
			    "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to %i would solve the problem.\n",
			    hard_iface->net_dev->name, hard_iface->net_dev->mtu,
			    ETH_DATA_LEN + max_header_len);

	if (!atomic_read(&bat_priv->fragmentation) &&
	    hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
		batadv_info(hard_iface->soft_iface,
			    "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. If you experience problems getting traffic through try increasing the MTU to %i.\n",
			    hard_iface->net_dev->name, hard_iface->net_dev->mtu,
			    ETH_DATA_LEN + max_header_len);

	if (batadv_hardif_is_iface_up(hard_iface))
		batadv_hardif_activate_interface(hard_iface);
	else
		batadv_err(hard_iface->soft_iface,
			   "Not using interface %s (retrying later): interface not active\n",
			   hard_iface->net_dev->name);

	/* begin scheduling originator messages on that interface */
	batadv_schedule_bat_ogm(hard_iface);

out:
	return 0;

err_upper:
	netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
err_dev:
	hard_iface->soft_iface = NULL;
	dev_put(soft_iface);
err:
	batadv_hardif_free_ref(hard_iface);
	return ret;
}

void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
				     enum batadv_hard_if_cleanup autodel)
{
	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	struct batadv_hard_iface *primary_if = NULL;

	if (hard_iface->if_status == BATADV_IF_ACTIVE)
		batadv_hardif_deactivate_interface(hard_iface);

	if (hard_iface->if_status != BATADV_IF_INACTIVE)
		goto out;

	batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
		    hard_iface->net_dev->name);
	dev_remove_pack(&hard_iface->batman_adv_ptype);

	bat_priv->num_ifaces--;
	batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);

	primary_if = batadv_primary_if_get_selected(bat_priv);
	if (hard_iface == primary_if) {
		struct batadv_hard_iface *new_if;

		new_if = batadv_hardif_get_active(hard_iface->soft_iface);
		batadv_primary_if_select(bat_priv, new_if);

		if (new_if)
			batadv_hardif_free_ref(new_if);
	}

	bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
	hard_iface->if_status = BATADV_IF_NOT_IN_USE;

	/* delete all references to this hard_iface */
	batadv_purge_orig_ref(bat_priv);
	batadv_purge_outstanding_packets(bat_priv, hard_iface);
	dev_put(hard_iface->soft_iface);

	/* nobody uses this interface anymore */
	if (!bat_priv->num_ifaces) {
		batadv_gw_check_client_stop(bat_priv);

		if (autodel == BATADV_IF_CLEANUP_AUTO)
			batadv_softif_destroy_sysfs(hard_iface->soft_iface);
	}

	netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
	hard_iface->soft_iface = NULL;
	batadv_hardif_free_ref(hard_iface);

out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
}

/**
 * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
 * @work: work queue item
 *
 * Free the parts of the hard interface which can not be removed under
 * rtnl lock (to prevent deadlock situations).
 */
static void batadv_hardif_remove_interface_finish(struct work_struct *work)
{
	struct batadv_hard_iface *hard_iface;

	hard_iface = container_of(work, struct batadv_hard_iface,
				  cleanup_work);

	batadv_debugfs_del_hardif(hard_iface);
	batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
	batadv_hardif_free_ref(hard_iface);
}

static struct batadv_hard_iface *
batadv_hardif_add_interface(struct net_device *net_dev)
{
	struct batadv_hard_iface *hard_iface;
	int ret;

	ASSERT_RTNL();

	ret = batadv_is_valid_iface(net_dev);
	if (ret != 1)
		goto out;

	dev_hold(net_dev);

	hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
	if (!hard_iface)
		goto release_dev;

	ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
	if (ret)
		goto free_if;

	hard_iface->if_num = -1;
	hard_iface->net_dev = net_dev;
	hard_iface->soft_iface = NULL;
	hard_iface->if_status = BATADV_IF_NOT_IN_USE;

	ret = batadv_debugfs_add_hardif(hard_iface);
	if (ret)
		goto free_sysfs;

	INIT_LIST_HEAD(&hard_iface->list);
	INIT_WORK(&hard_iface->cleanup_work,
		  batadv_hardif_remove_interface_finish);

	hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
	if (batadv_is_wifi_netdev(net_dev))
		hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;

	/* extra reference for return */
	atomic_set(&hard_iface->refcount, 2);

	batadv_check_known_mac_addr(hard_iface->net_dev);
	list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);

	return hard_iface;

free_sysfs:
	batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
free_if:
	kfree(hard_iface);
release_dev:
	dev_put(net_dev);
out:
	return NULL;
}

static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
{
	ASSERT_RTNL();

	/* first deactivate interface */
	if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
		batadv_hardif_disable_interface(hard_iface,
						BATADV_IF_CLEANUP_AUTO);

	if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
		return;

	hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
	queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
}

void batadv_hardif_remove_interfaces(void)
{
	struct batadv_hard_iface *hard_iface, *hard_iface_tmp;

	rtnl_lock();
	list_for_each_entry_safe(hard_iface, hard_iface_tmp,
				 &batadv_hardif_list, list) {
		list_del_rcu(&hard_iface->list);
		batadv_hardif_remove_interface(hard_iface);
	}
	rtnl_unlock();
}

static int batadv_hard_if_event(struct notifier_block *this,
				unsigned long event, void *ptr)
{
	struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
	struct batadv_hard_iface *hard_iface;
	struct batadv_hard_iface *primary_if = NULL;
	struct batadv_priv *bat_priv;

	if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
		batadv_sysfs_add_meshif(net_dev);
		bat_priv = netdev_priv(net_dev);
		batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
		return NOTIFY_DONE;
	}

	hard_iface = batadv_hardif_get_by_netdev(net_dev);
	if (!hard_iface && event == NETDEV_REGISTER)
		hard_iface = batadv_hardif_add_interface(net_dev);

	if (!hard_iface)
		goto out;

	switch (event) {
	case NETDEV_UP:
		batadv_hardif_activate_interface(hard_iface);
		break;
	case NETDEV_GOING_DOWN:
	case NETDEV_DOWN:
		batadv_hardif_deactivate_interface(hard_iface);
		break;
	case NETDEV_UNREGISTER:
		list_del_rcu(&hard_iface->list);

		batadv_hardif_remove_interface(hard_iface);
		break;
	case NETDEV_CHANGEMTU:
		if (hard_iface->soft_iface)
			batadv_update_min_mtu(hard_iface->soft_iface);
		break;
	case NETDEV_CHANGEADDR:
		if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
			goto hardif_put;

		batadv_check_known_mac_addr(hard_iface->net_dev);

		bat_priv = netdev_priv(hard_iface->soft_iface);
		bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);

		primary_if = batadv_primary_if_get_selected(bat_priv);
		if (!primary_if)
			goto hardif_put;

		if (hard_iface == primary_if)
			batadv_primary_if_update_addr(bat_priv, NULL);
		break;
	default:
		break;
	}

hardif_put:
	batadv_hardif_free_ref(hard_iface);
out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
	return NOTIFY_DONE;
}

struct notifier_block batadv_hard_if_notifier = {
	.notifier_call = batadv_hard_if_event,
};