Merge tag 'fixes-3.10-3' of git://git.infradead.org/users/jcooper/linux into fixes
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / batman-adv / originator.c
1 /* Copyright (C) 2009-2013 B.A.T.M.A.N. contributors:
2 *
3 * Marek Lindner, Simon Wunderlich
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of version 2 of the GNU General Public
7 * License as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA
18 */
19
20 #include "main.h"
21 #include "distributed-arp-table.h"
22 #include "originator.h"
23 #include "hash.h"
24 #include "translation-table.h"
25 #include "routing.h"
26 #include "gateway_client.h"
27 #include "hard-interface.h"
28 #include "unicast.h"
29 #include "soft-interface.h"
30 #include "bridge_loop_avoidance.h"
31 #include "network-coding.h"
32
33 /* hash class keys */
34 static struct lock_class_key batadv_orig_hash_lock_class_key;
35
36 static void batadv_purge_orig(struct work_struct *work);
37
38 /* returns 1 if they are the same originator */
39 static int batadv_compare_orig(const struct hlist_node *node, const void *data2)
40 {
41 const void *data1 = container_of(node, struct batadv_orig_node,
42 hash_entry);
43
44 return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
45 }
46
47 int batadv_originator_init(struct batadv_priv *bat_priv)
48 {
49 if (bat_priv->orig_hash)
50 return 0;
51
52 bat_priv->orig_hash = batadv_hash_new(1024);
53
54 if (!bat_priv->orig_hash)
55 goto err;
56
57 batadv_hash_set_lock_class(bat_priv->orig_hash,
58 &batadv_orig_hash_lock_class_key);
59
60 INIT_DELAYED_WORK(&bat_priv->orig_work, batadv_purge_orig);
61 queue_delayed_work(batadv_event_workqueue,
62 &bat_priv->orig_work,
63 msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));
64
65 return 0;
66
67 err:
68 return -ENOMEM;
69 }
70
71 void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node)
72 {
73 if (atomic_dec_and_test(&neigh_node->refcount))
74 kfree_rcu(neigh_node, rcu);
75 }
76
77 /* increases the refcounter of a found router */
78 struct batadv_neigh_node *
79 batadv_orig_node_get_router(struct batadv_orig_node *orig_node)
80 {
81 struct batadv_neigh_node *router;
82
83 rcu_read_lock();
84 router = rcu_dereference(orig_node->router);
85
86 if (router && !atomic_inc_not_zero(&router->refcount))
87 router = NULL;
88
89 rcu_read_unlock();
90 return router;
91 }
92
93 struct batadv_neigh_node *
94 batadv_neigh_node_new(struct batadv_hard_iface *hard_iface,
95 const uint8_t *neigh_addr, uint32_t seqno)
96 {
97 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
98 struct batadv_neigh_node *neigh_node;
99
100 neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC);
101 if (!neigh_node)
102 goto out;
103
104 INIT_HLIST_NODE(&neigh_node->list);
105
106 memcpy(neigh_node->addr, neigh_addr, ETH_ALEN);
107 spin_lock_init(&neigh_node->lq_update_lock);
108
109 /* extra reference for return */
110 atomic_set(&neigh_node->refcount, 2);
111
112 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
113 "Creating new neighbor %pM, initial seqno %d\n",
114 neigh_addr, seqno);
115
116 out:
117 return neigh_node;
118 }
119
120 static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
121 {
122 struct hlist_node *node_tmp;
123 struct batadv_neigh_node *neigh_node, *tmp_neigh_node;
124 struct batadv_orig_node *orig_node;
125
126 orig_node = container_of(rcu, struct batadv_orig_node, rcu);
127
128 spin_lock_bh(&orig_node->neigh_list_lock);
129
130 /* for all bonding members ... */
131 list_for_each_entry_safe(neigh_node, tmp_neigh_node,
132 &orig_node->bond_list, bonding_list) {
133 list_del_rcu(&neigh_node->bonding_list);
134 batadv_neigh_node_free_ref(neigh_node);
135 }
136
137 /* for all neighbors towards this originator ... */
138 hlist_for_each_entry_safe(neigh_node, node_tmp,
139 &orig_node->neigh_list, list) {
140 hlist_del_rcu(&neigh_node->list);
141 batadv_neigh_node_free_ref(neigh_node);
142 }
143
144 spin_unlock_bh(&orig_node->neigh_list_lock);
145
146 /* Free nc_nodes */
147 batadv_nc_purge_orig(orig_node->bat_priv, orig_node, NULL);
148
149 batadv_frag_list_free(&orig_node->frag_list);
150 batadv_tt_global_del_orig(orig_node->bat_priv, orig_node,
151 "originator timed out");
152
153 kfree(orig_node->tt_buff);
154 kfree(orig_node->bcast_own);
155 kfree(orig_node->bcast_own_sum);
156 kfree(orig_node);
157 }
158
159 /**
160 * batadv_orig_node_free_ref - decrement the orig node refcounter and possibly
161 * schedule an rcu callback for freeing it
162 * @orig_node: the orig node to free
163 */
164 void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node)
165 {
166 if (atomic_dec_and_test(&orig_node->refcount))
167 call_rcu(&orig_node->rcu, batadv_orig_node_free_rcu);
168 }
169
170 /**
171 * batadv_orig_node_free_ref_now - decrement the orig node refcounter and
172 * possibly free it (without rcu callback)
173 * @orig_node: the orig node to free
174 */
175 void batadv_orig_node_free_ref_now(struct batadv_orig_node *orig_node)
176 {
177 if (atomic_dec_and_test(&orig_node->refcount))
178 batadv_orig_node_free_rcu(&orig_node->rcu);
179 }
180
181 void batadv_originator_free(struct batadv_priv *bat_priv)
182 {
183 struct batadv_hashtable *hash = bat_priv->orig_hash;
184 struct hlist_node *node_tmp;
185 struct hlist_head *head;
186 spinlock_t *list_lock; /* spinlock to protect write access */
187 struct batadv_orig_node *orig_node;
188 uint32_t i;
189
190 if (!hash)
191 return;
192
193 cancel_delayed_work_sync(&bat_priv->orig_work);
194
195 bat_priv->orig_hash = NULL;
196
197 for (i = 0; i < hash->size; i++) {
198 head = &hash->table[i];
199 list_lock = &hash->list_locks[i];
200
201 spin_lock_bh(list_lock);
202 hlist_for_each_entry_safe(orig_node, node_tmp,
203 head, hash_entry) {
204 hlist_del_rcu(&orig_node->hash_entry);
205 batadv_orig_node_free_ref(orig_node);
206 }
207 spin_unlock_bh(list_lock);
208 }
209
210 batadv_hash_destroy(hash);
211 }
212
213 /* this function finds or creates an originator entry for the given
214 * address if it does not exits
215 */
216 struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv,
217 const uint8_t *addr)
218 {
219 struct batadv_orig_node *orig_node;
220 int size;
221 int hash_added;
222 unsigned long reset_time;
223
224 orig_node = batadv_orig_hash_find(bat_priv, addr);
225 if (orig_node)
226 return orig_node;
227
228 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
229 "Creating new originator: %pM\n", addr);
230
231 orig_node = kzalloc(sizeof(*orig_node), GFP_ATOMIC);
232 if (!orig_node)
233 return NULL;
234
235 INIT_HLIST_HEAD(&orig_node->neigh_list);
236 INIT_LIST_HEAD(&orig_node->bond_list);
237 spin_lock_init(&orig_node->ogm_cnt_lock);
238 spin_lock_init(&orig_node->bcast_seqno_lock);
239 spin_lock_init(&orig_node->neigh_list_lock);
240 spin_lock_init(&orig_node->tt_buff_lock);
241
242 batadv_nc_init_orig(orig_node);
243
244 /* extra reference for return */
245 atomic_set(&orig_node->refcount, 2);
246
247 orig_node->tt_initialised = false;
248 orig_node->bat_priv = bat_priv;
249 memcpy(orig_node->orig, addr, ETH_ALEN);
250 batadv_dat_init_orig_node_addr(orig_node);
251 orig_node->router = NULL;
252 orig_node->tt_crc = 0;
253 atomic_set(&orig_node->last_ttvn, 0);
254 orig_node->tt_buff = NULL;
255 orig_node->tt_buff_len = 0;
256 atomic_set(&orig_node->tt_size, 0);
257 reset_time = jiffies - 1 - msecs_to_jiffies(BATADV_RESET_PROTECTION_MS);
258 orig_node->bcast_seqno_reset = reset_time;
259 orig_node->batman_seqno_reset = reset_time;
260
261 atomic_set(&orig_node->bond_candidates, 0);
262
263 size = bat_priv->num_ifaces * sizeof(unsigned long) * BATADV_NUM_WORDS;
264
265 orig_node->bcast_own = kzalloc(size, GFP_ATOMIC);
266 if (!orig_node->bcast_own)
267 goto free_orig_node;
268
269 size = bat_priv->num_ifaces * sizeof(uint8_t);
270 orig_node->bcast_own_sum = kzalloc(size, GFP_ATOMIC);
271
272 INIT_LIST_HEAD(&orig_node->frag_list);
273 orig_node->last_frag_packet = 0;
274
275 if (!orig_node->bcast_own_sum)
276 goto free_bcast_own;
277
278 hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
279 batadv_choose_orig, orig_node,
280 &orig_node->hash_entry);
281 if (hash_added != 0)
282 goto free_bcast_own_sum;
283
284 return orig_node;
285 free_bcast_own_sum:
286 kfree(orig_node->bcast_own_sum);
287 free_bcast_own:
288 kfree(orig_node->bcast_own);
289 free_orig_node:
290 kfree(orig_node);
291 return NULL;
292 }
293
294 static bool
295 batadv_purge_orig_neighbors(struct batadv_priv *bat_priv,
296 struct batadv_orig_node *orig_node,
297 struct batadv_neigh_node **best_neigh_node)
298 {
299 struct hlist_node *node_tmp;
300 struct batadv_neigh_node *neigh_node;
301 bool neigh_purged = false;
302 unsigned long last_seen;
303 struct batadv_hard_iface *if_incoming;
304
305 *best_neigh_node = NULL;
306
307 spin_lock_bh(&orig_node->neigh_list_lock);
308
309 /* for all neighbors towards this originator ... */
310 hlist_for_each_entry_safe(neigh_node, node_tmp,
311 &orig_node->neigh_list, list) {
312 last_seen = neigh_node->last_seen;
313 if_incoming = neigh_node->if_incoming;
314
315 if ((batadv_has_timed_out(last_seen, BATADV_PURGE_TIMEOUT)) ||
316 (if_incoming->if_status == BATADV_IF_INACTIVE) ||
317 (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
318 (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED)) {
319 if ((if_incoming->if_status == BATADV_IF_INACTIVE) ||
320 (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
321 (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED))
322 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
323 "neighbor purge: originator %pM, neighbor: %pM, iface: %s\n",
324 orig_node->orig, neigh_node->addr,
325 if_incoming->net_dev->name);
326 else
327 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
328 "neighbor timeout: originator %pM, neighbor: %pM, last_seen: %u\n",
329 orig_node->orig, neigh_node->addr,
330 jiffies_to_msecs(last_seen));
331
332 neigh_purged = true;
333
334 hlist_del_rcu(&neigh_node->list);
335 batadv_bonding_candidate_del(orig_node, neigh_node);
336 batadv_neigh_node_free_ref(neigh_node);
337 } else {
338 if ((!*best_neigh_node) ||
339 (neigh_node->tq_avg > (*best_neigh_node)->tq_avg))
340 *best_neigh_node = neigh_node;
341 }
342 }
343
344 spin_unlock_bh(&orig_node->neigh_list_lock);
345 return neigh_purged;
346 }
347
348 static bool batadv_purge_orig_node(struct batadv_priv *bat_priv,
349 struct batadv_orig_node *orig_node)
350 {
351 struct batadv_neigh_node *best_neigh_node;
352
353 if (batadv_has_timed_out(orig_node->last_seen,
354 2 * BATADV_PURGE_TIMEOUT)) {
355 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
356 "Originator timeout: originator %pM, last_seen %u\n",
357 orig_node->orig,
358 jiffies_to_msecs(orig_node->last_seen));
359 return true;
360 } else {
361 if (batadv_purge_orig_neighbors(bat_priv, orig_node,
362 &best_neigh_node))
363 batadv_update_route(bat_priv, orig_node,
364 best_neigh_node);
365 }
366
367 return false;
368 }
369
370 static void _batadv_purge_orig(struct batadv_priv *bat_priv)
371 {
372 struct batadv_hashtable *hash = bat_priv->orig_hash;
373 struct hlist_node *node_tmp;
374 struct hlist_head *head;
375 spinlock_t *list_lock; /* spinlock to protect write access */
376 struct batadv_orig_node *orig_node;
377 uint32_t i;
378
379 if (!hash)
380 return;
381
382 /* for all origins... */
383 for (i = 0; i < hash->size; i++) {
384 head = &hash->table[i];
385 list_lock = &hash->list_locks[i];
386
387 spin_lock_bh(list_lock);
388 hlist_for_each_entry_safe(orig_node, node_tmp,
389 head, hash_entry) {
390 if (batadv_purge_orig_node(bat_priv, orig_node)) {
391 if (orig_node->gw_flags)
392 batadv_gw_node_delete(bat_priv,
393 orig_node);
394 hlist_del_rcu(&orig_node->hash_entry);
395 batadv_orig_node_free_ref(orig_node);
396 continue;
397 }
398
399 if (batadv_has_timed_out(orig_node->last_frag_packet,
400 BATADV_FRAG_TIMEOUT))
401 batadv_frag_list_free(&orig_node->frag_list);
402 }
403 spin_unlock_bh(list_lock);
404 }
405
406 batadv_gw_node_purge(bat_priv);
407 batadv_gw_election(bat_priv);
408 }
409
410 static void batadv_purge_orig(struct work_struct *work)
411 {
412 struct delayed_work *delayed_work;
413 struct batadv_priv *bat_priv;
414
415 delayed_work = container_of(work, struct delayed_work, work);
416 bat_priv = container_of(delayed_work, struct batadv_priv, orig_work);
417 _batadv_purge_orig(bat_priv);
418 queue_delayed_work(batadv_event_workqueue,
419 &bat_priv->orig_work,
420 msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));
421 }
422
423 void batadv_purge_orig_ref(struct batadv_priv *bat_priv)
424 {
425 _batadv_purge_orig(bat_priv);
426 }
427
428 int batadv_orig_seq_print_text(struct seq_file *seq, void *offset)
429 {
430 struct net_device *net_dev = (struct net_device *)seq->private;
431 struct batadv_priv *bat_priv = netdev_priv(net_dev);
432 struct batadv_hashtable *hash = bat_priv->orig_hash;
433 struct hlist_head *head;
434 struct batadv_hard_iface *primary_if;
435 struct batadv_orig_node *orig_node;
436 struct batadv_neigh_node *neigh_node, *neigh_node_tmp;
437 int batman_count = 0;
438 int last_seen_secs;
439 int last_seen_msecs;
440 unsigned long last_seen_jiffies;
441 uint32_t i;
442
443 primary_if = batadv_seq_print_text_primary_if_get(seq);
444 if (!primary_if)
445 goto out;
446
447 seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
448 BATADV_SOURCE_VERSION, primary_if->net_dev->name,
449 primary_if->net_dev->dev_addr, net_dev->name);
450 seq_printf(seq, " %-15s %s (%s/%i) %17s [%10s]: %20s ...\n",
451 "Originator", "last-seen", "#", BATADV_TQ_MAX_VALUE,
452 "Nexthop", "outgoingIF", "Potential nexthops");
453
454 for (i = 0; i < hash->size; i++) {
455 head = &hash->table[i];
456
457 rcu_read_lock();
458 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
459 neigh_node = batadv_orig_node_get_router(orig_node);
460 if (!neigh_node)
461 continue;
462
463 if (neigh_node->tq_avg == 0)
464 goto next;
465
466 last_seen_jiffies = jiffies - orig_node->last_seen;
467 last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
468 last_seen_secs = last_seen_msecs / 1000;
469 last_seen_msecs = last_seen_msecs % 1000;
470
471 seq_printf(seq, "%pM %4i.%03is (%3i) %pM [%10s]:",
472 orig_node->orig, last_seen_secs,
473 last_seen_msecs, neigh_node->tq_avg,
474 neigh_node->addr,
475 neigh_node->if_incoming->net_dev->name);
476
477 hlist_for_each_entry_rcu(neigh_node_tmp,
478 &orig_node->neigh_list, list) {
479 seq_printf(seq, " %pM (%3i)",
480 neigh_node_tmp->addr,
481 neigh_node_tmp->tq_avg);
482 }
483
484 seq_puts(seq, "\n");
485 batman_count++;
486
487 next:
488 batadv_neigh_node_free_ref(neigh_node);
489 }
490 rcu_read_unlock();
491 }
492
493 if (batman_count == 0)
494 seq_puts(seq, "No batman nodes in range ...\n");
495
496 out:
497 if (primary_if)
498 batadv_hardif_free_ref(primary_if);
499 return 0;
500 }
501
502 static int batadv_orig_node_add_if(struct batadv_orig_node *orig_node,
503 int max_if_num)
504 {
505 void *data_ptr;
506 size_t data_size, old_size;
507
508 data_size = max_if_num * sizeof(unsigned long) * BATADV_NUM_WORDS;
509 old_size = (max_if_num - 1) * sizeof(unsigned long) * BATADV_NUM_WORDS;
510 data_ptr = kmalloc(data_size, GFP_ATOMIC);
511 if (!data_ptr)
512 return -ENOMEM;
513
514 memcpy(data_ptr, orig_node->bcast_own, old_size);
515 kfree(orig_node->bcast_own);
516 orig_node->bcast_own = data_ptr;
517
518 data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
519 if (!data_ptr)
520 return -ENOMEM;
521
522 memcpy(data_ptr, orig_node->bcast_own_sum,
523 (max_if_num - 1) * sizeof(uint8_t));
524 kfree(orig_node->bcast_own_sum);
525 orig_node->bcast_own_sum = data_ptr;
526
527 return 0;
528 }
529
530 int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface,
531 int max_if_num)
532 {
533 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
534 struct batadv_hashtable *hash = bat_priv->orig_hash;
535 struct hlist_head *head;
536 struct batadv_orig_node *orig_node;
537 uint32_t i;
538 int ret;
539
540 /* resize all orig nodes because orig_node->bcast_own(_sum) depend on
541 * if_num
542 */
543 for (i = 0; i < hash->size; i++) {
544 head = &hash->table[i];
545
546 rcu_read_lock();
547 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
548 spin_lock_bh(&orig_node->ogm_cnt_lock);
549 ret = batadv_orig_node_add_if(orig_node, max_if_num);
550 spin_unlock_bh(&orig_node->ogm_cnt_lock);
551
552 if (ret == -ENOMEM)
553 goto err;
554 }
555 rcu_read_unlock();
556 }
557
558 return 0;
559
560 err:
561 rcu_read_unlock();
562 return -ENOMEM;
563 }
564
565 static int batadv_orig_node_del_if(struct batadv_orig_node *orig_node,
566 int max_if_num, int del_if_num)
567 {
568 void *data_ptr = NULL;
569 int chunk_size;
570
571 /* last interface was removed */
572 if (max_if_num == 0)
573 goto free_bcast_own;
574
575 chunk_size = sizeof(unsigned long) * BATADV_NUM_WORDS;
576 data_ptr = kmalloc(max_if_num * chunk_size, GFP_ATOMIC);
577 if (!data_ptr)
578 return -ENOMEM;
579
580 /* copy first part */
581 memcpy(data_ptr, orig_node->bcast_own, del_if_num * chunk_size);
582
583 /* copy second part */
584 memcpy((char *)data_ptr + del_if_num * chunk_size,
585 orig_node->bcast_own + ((del_if_num + 1) * chunk_size),
586 (max_if_num - del_if_num) * chunk_size);
587
588 free_bcast_own:
589 kfree(orig_node->bcast_own);
590 orig_node->bcast_own = data_ptr;
591
592 if (max_if_num == 0)
593 goto free_own_sum;
594
595 data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
596 if (!data_ptr)
597 return -ENOMEM;
598
599 memcpy(data_ptr, orig_node->bcast_own_sum,
600 del_if_num * sizeof(uint8_t));
601
602 memcpy((char *)data_ptr + del_if_num * sizeof(uint8_t),
603 orig_node->bcast_own_sum + ((del_if_num + 1) * sizeof(uint8_t)),
604 (max_if_num - del_if_num) * sizeof(uint8_t));
605
606 free_own_sum:
607 kfree(orig_node->bcast_own_sum);
608 orig_node->bcast_own_sum = data_ptr;
609
610 return 0;
611 }
612
613 int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface,
614 int max_if_num)
615 {
616 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
617 struct batadv_hashtable *hash = bat_priv->orig_hash;
618 struct hlist_head *head;
619 struct batadv_hard_iface *hard_iface_tmp;
620 struct batadv_orig_node *orig_node;
621 uint32_t i;
622 int ret;
623
624 /* resize all orig nodes because orig_node->bcast_own(_sum) depend on
625 * if_num
626 */
627 for (i = 0; i < hash->size; i++) {
628 head = &hash->table[i];
629
630 rcu_read_lock();
631 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
632 spin_lock_bh(&orig_node->ogm_cnt_lock);
633 ret = batadv_orig_node_del_if(orig_node, max_if_num,
634 hard_iface->if_num);
635 spin_unlock_bh(&orig_node->ogm_cnt_lock);
636
637 if (ret == -ENOMEM)
638 goto err;
639 }
640 rcu_read_unlock();
641 }
642
643 /* renumber remaining batman interfaces _inside_ of orig_hash_lock */
644 rcu_read_lock();
645 list_for_each_entry_rcu(hard_iface_tmp, &batadv_hardif_list, list) {
646 if (hard_iface_tmp->if_status == BATADV_IF_NOT_IN_USE)
647 continue;
648
649 if (hard_iface == hard_iface_tmp)
650 continue;
651
652 if (hard_iface->soft_iface != hard_iface_tmp->soft_iface)
653 continue;
654
655 if (hard_iface_tmp->if_num > hard_iface->if_num)
656 hard_iface_tmp->if_num--;
657 }
658 rcu_read_unlock();
659
660 hard_iface->if_num = -1;
661 return 0;
662
663 err:
664 rcu_read_unlock();
665 return -ENOMEM;
666 }