summaryrefslogtreecommitdiff
path: root/net/batman-adv/originator.c
blob: 8d1b16eb12d13974ad6cba87c360c0aef5a450a3 (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
/* Copyright (C) 2009-2013 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 */

#include "main.h"
#include "distributed-arp-table.h"
#include "originator.h"
#include "hash.h"
#include "translation-table.h"
#include "routing.h"
#include "gateway_client.h"
#include "hard-interface.h"
#include "soft-interface.h"
#include "bridge_loop_avoidance.h"
#include "network-coding.h"
#include "fragmentation.h"

/* hash class keys */
static struct lock_class_key batadv_orig_hash_lock_class_key;

static void batadv_purge_orig(struct work_struct *work);

/* returns 1 if they are the same originator */
int batadv_compare_orig(const struct hlist_node *node, const void *data2)
{
	const void *data1 = container_of(node, struct batadv_orig_node,
					 hash_entry);

	return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
}

/**
 * batadv_orig_node_vlan_get - get an orig_node_vlan object
 * @orig_node: the originator serving the VLAN
 * @vid: the VLAN identifier
 *
 * Returns the vlan object identified by vid and belonging to orig_node or NULL
 * if it does not exist.
 */
struct batadv_orig_node_vlan *
batadv_orig_node_vlan_get(struct batadv_orig_node *orig_node,
			  unsigned short vid)
{
	struct batadv_orig_node_vlan *vlan = NULL, *tmp;

	rcu_read_lock();
	list_for_each_entry_rcu(tmp, &orig_node->vlan_list, list) {
		if (tmp->vid != vid)
			continue;

		if (!atomic_inc_not_zero(&tmp->refcount))
			continue;

		vlan = tmp;

		break;
	}
	rcu_read_unlock();

	return vlan;
}

/**
 * batadv_orig_node_vlan_new - search and possibly create an orig_node_vlan
 *  object
 * @orig_node: the originator serving the VLAN
 * @vid: the VLAN identifier
 *
 * Returns NULL in case of failure or the vlan object identified by vid and
 * belonging to orig_node otherwise. The object is created and added to the list
 * if it does not exist.
 *
 * The object is returned with refcounter increased by 1.
 */
struct batadv_orig_node_vlan *
batadv_orig_node_vlan_new(struct batadv_orig_node *orig_node,
			  unsigned short vid)
{
	struct batadv_orig_node_vlan *vlan;

	spin_lock_bh(&orig_node->vlan_list_lock);

	/* first look if an object for this vid already exists */
	vlan = batadv_orig_node_vlan_get(orig_node, vid);
	if (vlan)
		goto out;

	vlan = kzalloc(sizeof(*vlan), GFP_ATOMIC);
	if (!vlan)
		goto out;

	atomic_set(&vlan->refcount, 2);
	vlan->vid = vid;

	list_add_rcu(&vlan->list, &orig_node->vlan_list);

out:
	spin_unlock_bh(&orig_node->vlan_list_lock);

	return vlan;
}

/**
 * batadv_orig_node_vlan_free_ref - decrement the refcounter and possibly free
 *  the originator-vlan object
 * @orig_vlan: the originator-vlan object to release
 */
void batadv_orig_node_vlan_free_ref(struct batadv_orig_node_vlan *orig_vlan)
{
	if (atomic_dec_and_test(&orig_vlan->refcount))
		kfree_rcu(orig_vlan, rcu);
}

int batadv_originator_init(struct batadv_priv *bat_priv)
{
	if (bat_priv->orig_hash)
		return 0;

	bat_priv->orig_hash = batadv_hash_new(1024);

	if (!bat_priv->orig_hash)
		goto err;

	batadv_hash_set_lock_class(bat_priv->orig_hash,
				   &batadv_orig_hash_lock_class_key);

	INIT_DELAYED_WORK(&bat_priv->orig_work, batadv_purge_orig);
	queue_delayed_work(batadv_event_workqueue,
			   &bat_priv->orig_work,
			   msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));

	return 0;

err:
	return -ENOMEM;
}

void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node)
{
	if (atomic_dec_and_test(&neigh_node->refcount))
		kfree_rcu(neigh_node, rcu);
}

/* increases the refcounter of a found router */
struct batadv_neigh_node *
batadv_orig_node_get_router(struct batadv_orig_node *orig_node)
{
	struct batadv_neigh_node *router;

	rcu_read_lock();
	router = rcu_dereference(orig_node->router);

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

	rcu_read_unlock();
	return router;
}

/**
 * batadv_neigh_node_new - create and init a new neigh_node object
 * @hard_iface: the interface where the neighbour is connected to
 * @neigh_addr: the mac address of the neighbour interface
 * @orig_node: originator object representing the neighbour
 *
 * Allocates a new neigh_node object and initialises all the generic fields.
 * Returns the new object or NULL on failure.
 */
struct batadv_neigh_node *
batadv_neigh_node_new(struct batadv_hard_iface *hard_iface,
		      const uint8_t *neigh_addr,
		      struct batadv_orig_node *orig_node)
{
	struct batadv_neigh_node *neigh_node;

	neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC);
	if (!neigh_node)
		goto out;

	INIT_HLIST_NODE(&neigh_node->list);

	memcpy(neigh_node->addr, neigh_addr, ETH_ALEN);
	neigh_node->if_incoming = hard_iface;
	neigh_node->orig_node = orig_node;

	INIT_LIST_HEAD(&neigh_node->bonding_list);

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

out:
	return neigh_node;
}

static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
{
	struct hlist_node *node_tmp;
	struct batadv_neigh_node *neigh_node, *tmp_neigh_node;
	struct batadv_orig_node *orig_node;

	orig_node = container_of(rcu, struct batadv_orig_node, rcu);

	spin_lock_bh(&orig_node->neigh_list_lock);

	/* for all bonding members ... */
	list_for_each_entry_safe(neigh_node, tmp_neigh_node,
				 &orig_node->bond_list, bonding_list) {
		list_del_rcu(&neigh_node->bonding_list);
		batadv_neigh_node_free_ref(neigh_node);
	}

	/* for all neighbors towards this originator ... */
	hlist_for_each_entry_safe(neigh_node, node_tmp,
				  &orig_node->neigh_list, list) {
		hlist_del_rcu(&neigh_node->list);
		batadv_neigh_node_free_ref(neigh_node);
	}

	spin_unlock_bh(&orig_node->neigh_list_lock);

	/* Free nc_nodes */
	batadv_nc_purge_orig(orig_node->bat_priv, orig_node, NULL);

	batadv_frag_purge_orig(orig_node, NULL);

	batadv_tt_global_del_orig(orig_node->bat_priv, orig_node, -1,
				  "originator timed out");

	kfree(orig_node->tt_buff);
	kfree(orig_node->bat_iv.bcast_own);
	kfree(orig_node->bat_iv.bcast_own_sum);
	kfree(orig_node);
}

/**
 * batadv_orig_node_free_ref - decrement the orig node refcounter and possibly
 * schedule an rcu callback for freeing it
 * @orig_node: the orig node to free
 */
void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node)
{
	if (atomic_dec_and_test(&orig_node->refcount))
		call_rcu(&orig_node->rcu, batadv_orig_node_free_rcu);
}

/**
 * batadv_orig_node_free_ref_now - decrement the orig node refcounter and
 * possibly free it (without rcu callback)
 * @orig_node: the orig node to free
 */
void batadv_orig_node_free_ref_now(struct batadv_orig_node *orig_node)
{
	if (atomic_dec_and_test(&orig_node->refcount))
		batadv_orig_node_free_rcu(&orig_node->rcu);
}

void batadv_originator_free(struct batadv_priv *bat_priv)
{
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	struct hlist_node *node_tmp;
	struct hlist_head *head;
	spinlock_t *list_lock; /* spinlock to protect write access */
	struct batadv_orig_node *orig_node;
	uint32_t i;

	if (!hash)
		return;

	cancel_delayed_work_sync(&bat_priv->orig_work);

	bat_priv->orig_hash = NULL;

	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];
		list_lock = &hash->list_locks[i];

		spin_lock_bh(list_lock);
		hlist_for_each_entry_safe(orig_node, node_tmp,
					  head, hash_entry) {
			hlist_del_rcu(&orig_node->hash_entry);
			batadv_orig_node_free_ref(orig_node);
		}
		spin_unlock_bh(list_lock);
	}

	batadv_hash_destroy(hash);
}

/**
 * batadv_orig_node_new - creates a new orig_node
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the mac address of the originator
 *
 * Creates a new originator object and initialise all the generic fields.
 * The new object is not added to the originator list.
 * Returns the newly created object or NULL on failure.
 */
struct batadv_orig_node *batadv_orig_node_new(struct batadv_priv *bat_priv,
					      const uint8_t *addr)
{
	struct batadv_orig_node *orig_node;
	struct batadv_orig_node_vlan *vlan;
	unsigned long reset_time;
	int i;

	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
		   "Creating new originator: %pM\n", addr);

	orig_node = kzalloc(sizeof(*orig_node), GFP_ATOMIC);
	if (!orig_node)
		return NULL;

	INIT_HLIST_HEAD(&orig_node->neigh_list);
	INIT_LIST_HEAD(&orig_node->bond_list);
	INIT_LIST_HEAD(&orig_node->vlan_list);
	spin_lock_init(&orig_node->bcast_seqno_lock);
	spin_lock_init(&orig_node->neigh_list_lock);
	spin_lock_init(&orig_node->tt_buff_lock);
	spin_lock_init(&orig_node->tt_lock);
	spin_lock_init(&orig_node->vlan_list_lock);

	batadv_nc_init_orig(orig_node);

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

	orig_node->tt_initialised = false;
	orig_node->bat_priv = bat_priv;
	memcpy(orig_node->orig, addr, ETH_ALEN);
	batadv_dat_init_orig_node_addr(orig_node);
	orig_node->router = NULL;
	atomic_set(&orig_node->last_ttvn, 0);
	orig_node->tt_buff = NULL;
	orig_node->tt_buff_len = 0;
	reset_time = jiffies - 1 - msecs_to_jiffies(BATADV_RESET_PROTECTION_MS);
	orig_node->bcast_seqno_reset = reset_time;
	orig_node->batman_seqno_reset = reset_time;

	atomic_set(&orig_node->bond_candidates, 0);

	/* create a vlan object for the "untagged" LAN */
	vlan = batadv_orig_node_vlan_new(orig_node, BATADV_NO_FLAGS);
	if (!vlan)
		goto free_orig_node;
	/* batadv_orig_node_vlan_new() increases the refcounter.
	 * Immediately release vlan since it is not needed anymore in this
	 * context
	 */
	batadv_orig_node_vlan_free_ref(vlan);

	for (i = 0; i < BATADV_FRAG_BUFFER_COUNT; i++) {
		INIT_HLIST_HEAD(&orig_node->fragments[i].head);
		spin_lock_init(&orig_node->fragments[i].lock);
		orig_node->fragments[i].size = 0;
	}

	return orig_node;
free_orig_node:
	kfree(orig_node);
	return NULL;
}

static bool
batadv_purge_orig_neighbors(struct batadv_priv *bat_priv,
			    struct batadv_orig_node *orig_node,
			    struct batadv_neigh_node **best_neigh_node)
{
	struct hlist_node *node_tmp;
	struct batadv_neigh_node *neigh_node;
	bool neigh_purged = false;
	unsigned long last_seen;
	struct batadv_hard_iface *if_incoming;
	uint8_t best_metric = 0;

	*best_neigh_node = NULL;

	spin_lock_bh(&orig_node->neigh_list_lock);

	/* for all neighbors towards this originator ... */
	hlist_for_each_entry_safe(neigh_node, node_tmp,
				  &orig_node->neigh_list, list) {
		last_seen = neigh_node->last_seen;
		if_incoming = neigh_node->if_incoming;

		if ((batadv_has_timed_out(last_seen, BATADV_PURGE_TIMEOUT)) ||
		    (if_incoming->if_status == BATADV_IF_INACTIVE) ||
		    (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
		    (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED)) {
			if ((if_incoming->if_status == BATADV_IF_INACTIVE) ||
			    (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
			    (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED))
				batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
					   "neighbor purge: originator %pM, neighbor: %pM, iface: %s\n",
					   orig_node->orig, neigh_node->addr,
					   if_incoming->net_dev->name);
			else
				batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
					   "neighbor timeout: originator %pM, neighbor: %pM, last_seen: %u\n",
					   orig_node->orig, neigh_node->addr,
					   jiffies_to_msecs(last_seen));

			neigh_purged = true;

			hlist_del_rcu(&neigh_node->list);
			batadv_bonding_candidate_del(orig_node, neigh_node);
			batadv_neigh_node_free_ref(neigh_node);
		} else {
			if ((!*best_neigh_node) ||
			    (neigh_node->bat_iv.tq_avg > best_metric)) {
				*best_neigh_node = neigh_node;
				best_metric = neigh_node->bat_iv.tq_avg;
			}
		}
	}

	spin_unlock_bh(&orig_node->neigh_list_lock);
	return neigh_purged;
}

static bool batadv_purge_orig_node(struct batadv_priv *bat_priv,
				   struct batadv_orig_node *orig_node)
{
	struct batadv_neigh_node *best_neigh_node;

	if (batadv_has_timed_out(orig_node->last_seen,
				 2 * BATADV_PURGE_TIMEOUT)) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Originator timeout: originator %pM, last_seen %u\n",
			   orig_node->orig,
			   jiffies_to_msecs(orig_node->last_seen));
		return true;
	} else {
		if (batadv_purge_orig_neighbors(bat_priv, orig_node,
						&best_neigh_node))
			batadv_update_route(bat_priv, orig_node,
					    best_neigh_node);
	}

	return false;
}

static void _batadv_purge_orig(struct batadv_priv *bat_priv)
{
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	struct hlist_node *node_tmp;
	struct hlist_head *head;
	spinlock_t *list_lock; /* spinlock to protect write access */
	struct batadv_orig_node *orig_node;
	uint32_t i;

	if (!hash)
		return;

	/* for all origins... */
	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];
		list_lock = &hash->list_locks[i];

		spin_lock_bh(list_lock);
		hlist_for_each_entry_safe(orig_node, node_tmp,
					  head, hash_entry) {
			if (batadv_purge_orig_node(bat_priv, orig_node)) {
				batadv_gw_node_delete(bat_priv, orig_node);
				hlist_del_rcu(&orig_node->hash_entry);
				batadv_orig_node_free_ref(orig_node);
				continue;
			}

			batadv_frag_purge_orig(orig_node,
					       batadv_frag_check_entry);
		}
		spin_unlock_bh(list_lock);
	}

	batadv_gw_node_purge(bat_priv);
	batadv_gw_election(bat_priv);
}

static void batadv_purge_orig(struct work_struct *work)
{
	struct delayed_work *delayed_work;
	struct batadv_priv *bat_priv;

	delayed_work = container_of(work, struct delayed_work, work);
	bat_priv = container_of(delayed_work, struct batadv_priv, orig_work);
	_batadv_purge_orig(bat_priv);
	queue_delayed_work(batadv_event_workqueue,
			   &bat_priv->orig_work,
			   msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));
}

void batadv_purge_orig_ref(struct batadv_priv *bat_priv)
{
	_batadv_purge_orig(bat_priv);
}

int batadv_orig_seq_print_text(struct seq_file *seq, void *offset)
{
	struct net_device *net_dev = (struct net_device *)seq->private;
	struct batadv_priv *bat_priv = netdev_priv(net_dev);
	struct batadv_hard_iface *primary_if;

	primary_if = batadv_seq_print_text_primary_if_get(seq);
	if (!primary_if)
		return 0;

	seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s %s)]\n",
		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
		   primary_if->net_dev->dev_addr, net_dev->name,
		   bat_priv->bat_algo_ops->name);

	batadv_hardif_free_ref(primary_if);

	if (!bat_priv->bat_algo_ops->bat_orig_print) {
		seq_puts(seq,
			 "No printing function for this routing protocol\n");
		return 0;
	}

	bat_priv->bat_algo_ops->bat_orig_print(bat_priv, seq);

	return 0;
}

static int batadv_orig_node_add_if(struct batadv_orig_node *orig_node,
				   int max_if_num)
{
	void *data_ptr;
	size_t data_size, old_size;

	data_size = max_if_num * sizeof(unsigned long) * BATADV_NUM_WORDS;
	old_size = (max_if_num - 1) * sizeof(unsigned long) * BATADV_NUM_WORDS;
	data_ptr = kmalloc(data_size, GFP_ATOMIC);
	if (!data_ptr)
		return -ENOMEM;

	memcpy(data_ptr, orig_node->bat_iv.bcast_own, old_size);
	kfree(orig_node->bat_iv.bcast_own);
	orig_node->bat_iv.bcast_own = data_ptr;

	data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
	if (!data_ptr)
		return -ENOMEM;

	memcpy(data_ptr, orig_node->bat_iv.bcast_own_sum,
	       (max_if_num - 1) * sizeof(uint8_t));
	kfree(orig_node->bat_iv.bcast_own_sum);
	orig_node->bat_iv.bcast_own_sum = data_ptr;

	return 0;
}

int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface,
			    int max_if_num)
{
	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	struct hlist_head *head;
	struct batadv_orig_node *orig_node;
	uint32_t i;
	int ret;

	/* resize all orig nodes because orig_node->bcast_own(_sum) depend on
	 * if_num
	 */
	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
			spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
			ret = batadv_orig_node_add_if(orig_node, max_if_num);
			spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);

			if (ret == -ENOMEM)
				goto err;
		}
		rcu_read_unlock();
	}

	return 0;

err:
	rcu_read_unlock();
	return -ENOMEM;
}

static int batadv_orig_node_del_if(struct batadv_orig_node *orig_node,
				   int max_if_num, int del_if_num)
{
	int chunk_size, if_offset;
	void *data_ptr = NULL;

	/* last interface was removed */
	if (max_if_num == 0)
		goto free_bcast_own;

	chunk_size = sizeof(unsigned long) * BATADV_NUM_WORDS;
	data_ptr = kmalloc(max_if_num * chunk_size, GFP_ATOMIC);
	if (!data_ptr)
		return -ENOMEM;

	/* copy first part */
	memcpy(data_ptr, orig_node->bat_iv.bcast_own, del_if_num * chunk_size);

	/* copy second part */
	memcpy((char *)data_ptr + del_if_num * chunk_size,
	       orig_node->bat_iv.bcast_own + ((del_if_num + 1) * chunk_size),
	       (max_if_num - del_if_num) * chunk_size);

free_bcast_own:
	kfree(orig_node->bat_iv.bcast_own);
	orig_node->bat_iv.bcast_own = data_ptr;

	if (max_if_num == 0)
		goto free_own_sum;

	data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
	if (!data_ptr)
		return -ENOMEM;

	memcpy(data_ptr, orig_node->bat_iv.bcast_own_sum,
	       del_if_num * sizeof(uint8_t));

	if_offset = (del_if_num + 1) * sizeof(uint8_t);
	memcpy((char *)data_ptr + del_if_num * sizeof(uint8_t),
	       orig_node->bat_iv.bcast_own_sum + if_offset,
	       (max_if_num - del_if_num) * sizeof(uint8_t));

free_own_sum:
	kfree(orig_node->bat_iv.bcast_own_sum);
	orig_node->bat_iv.bcast_own_sum = data_ptr;

	return 0;
}

int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface,
			    int max_if_num)
{
	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	struct hlist_head *head;
	struct batadv_hard_iface *hard_iface_tmp;
	struct batadv_orig_node *orig_node;
	uint32_t i;
	int ret;

	/* resize all orig nodes because orig_node->bcast_own(_sum) depend on
	 * if_num
	 */
	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
			spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
			ret = batadv_orig_node_del_if(orig_node, max_if_num,
						      hard_iface->if_num);
			spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);

			if (ret == -ENOMEM)
				goto err;
		}
		rcu_read_unlock();
	}

	/* renumber remaining batman interfaces _inside_ of orig_hash_lock */
	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface_tmp, &batadv_hardif_list, list) {
		if (hard_iface_tmp->if_status == BATADV_IF_NOT_IN_USE)
			continue;

		if (hard_iface == hard_iface_tmp)
			continue;

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

		if (hard_iface_tmp->if_num > hard_iface->if_num)
			hard_iface_tmp->if_num--;
	}
	rcu_read_unlock();

	hard_iface->if_num = -1;
	return 0;

err:
	rcu_read_unlock();
	return -ENOMEM;
}