batman-adv: make struct batadv_orig_node algorithm agnostic
[cascardo/linux.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 "soft-interface.h"
29 #include "bridge_loop_avoidance.h"
30 #include "network-coding.h"
31 #include "fragmentation.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 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 /**
48  * batadv_orig_node_vlan_get - get an orig_node_vlan object
49  * @orig_node: the originator serving the VLAN
50  * @vid: the VLAN identifier
51  *
52  * Returns the vlan object identified by vid and belonging to orig_node or NULL
53  * if it does not exist.
54  */
55 struct batadv_orig_node_vlan *
56 batadv_orig_node_vlan_get(struct batadv_orig_node *orig_node,
57                           unsigned short vid)
58 {
59         struct batadv_orig_node_vlan *vlan = NULL, *tmp;
60
61         rcu_read_lock();
62         list_for_each_entry_rcu(tmp, &orig_node->vlan_list, list) {
63                 if (tmp->vid != vid)
64                         continue;
65
66                 if (!atomic_inc_not_zero(&tmp->refcount))
67                         continue;
68
69                 vlan = tmp;
70
71                 break;
72         }
73         rcu_read_unlock();
74
75         return vlan;
76 }
77
78 /**
79  * batadv_orig_node_vlan_new - search and possibly create an orig_node_vlan
80  *  object
81  * @orig_node: the originator serving the VLAN
82  * @vid: the VLAN identifier
83  *
84  * Returns NULL in case of failure or the vlan object identified by vid and
85  * belonging to orig_node otherwise. The object is created and added to the list
86  * if it does not exist.
87  *
88  * The object is returned with refcounter increased by 1.
89  */
90 struct batadv_orig_node_vlan *
91 batadv_orig_node_vlan_new(struct batadv_orig_node *orig_node,
92                           unsigned short vid)
93 {
94         struct batadv_orig_node_vlan *vlan;
95
96         spin_lock_bh(&orig_node->vlan_list_lock);
97
98         /* first look if an object for this vid already exists */
99         vlan = batadv_orig_node_vlan_get(orig_node, vid);
100         if (vlan)
101                 goto out;
102
103         vlan = kzalloc(sizeof(*vlan), GFP_ATOMIC);
104         if (!vlan)
105                 goto out;
106
107         atomic_set(&vlan->refcount, 2);
108         vlan->vid = vid;
109
110         list_add_rcu(&vlan->list, &orig_node->vlan_list);
111
112 out:
113         spin_unlock_bh(&orig_node->vlan_list_lock);
114
115         return vlan;
116 }
117
118 /**
119  * batadv_orig_node_vlan_free_ref - decrement the refcounter and possibly free
120  *  the originator-vlan object
121  * @orig_vlan: the originator-vlan object to release
122  */
123 void batadv_orig_node_vlan_free_ref(struct batadv_orig_node_vlan *orig_vlan)
124 {
125         if (atomic_dec_and_test(&orig_vlan->refcount))
126                 kfree_rcu(orig_vlan, rcu);
127 }
128
129 int batadv_originator_init(struct batadv_priv *bat_priv)
130 {
131         if (bat_priv->orig_hash)
132                 return 0;
133
134         bat_priv->orig_hash = batadv_hash_new(1024);
135
136         if (!bat_priv->orig_hash)
137                 goto err;
138
139         batadv_hash_set_lock_class(bat_priv->orig_hash,
140                                    &batadv_orig_hash_lock_class_key);
141
142         INIT_DELAYED_WORK(&bat_priv->orig_work, batadv_purge_orig);
143         queue_delayed_work(batadv_event_workqueue,
144                            &bat_priv->orig_work,
145                            msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));
146
147         return 0;
148
149 err:
150         return -ENOMEM;
151 }
152
153 void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node)
154 {
155         if (atomic_dec_and_test(&neigh_node->refcount))
156                 kfree_rcu(neigh_node, rcu);
157 }
158
159 /* increases the refcounter of a found router */
160 struct batadv_neigh_node *
161 batadv_orig_node_get_router(struct batadv_orig_node *orig_node)
162 {
163         struct batadv_neigh_node *router;
164
165         rcu_read_lock();
166         router = rcu_dereference(orig_node->router);
167
168         if (router && !atomic_inc_not_zero(&router->refcount))
169                 router = NULL;
170
171         rcu_read_unlock();
172         return router;
173 }
174
175 /**
176  * batadv_neigh_node_new - create and init a new neigh_node object
177  * @hard_iface: the interface where the neighbour is connected to
178  * @neigh_addr: the mac address of the neighbour interface
179  * @orig_node: originator object representing the neighbour
180  *
181  * Allocates a new neigh_node object and initialises all the generic fields.
182  * Returns the new object or NULL on failure.
183  */
184 struct batadv_neigh_node *
185 batadv_neigh_node_new(struct batadv_hard_iface *hard_iface,
186                       const uint8_t *neigh_addr,
187                       struct batadv_orig_node *orig_node)
188 {
189         struct batadv_neigh_node *neigh_node;
190
191         neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC);
192         if (!neigh_node)
193                 goto out;
194
195         INIT_HLIST_NODE(&neigh_node->list);
196
197         memcpy(neigh_node->addr, neigh_addr, ETH_ALEN);
198         neigh_node->if_incoming = hard_iface;
199         neigh_node->orig_node = orig_node;
200
201         INIT_LIST_HEAD(&neigh_node->bonding_list);
202
203         /* extra reference for return */
204         atomic_set(&neigh_node->refcount, 2);
205
206 out:
207         return neigh_node;
208 }
209
210 static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
211 {
212         struct hlist_node *node_tmp;
213         struct batadv_neigh_node *neigh_node, *tmp_neigh_node;
214         struct batadv_orig_node *orig_node;
215
216         orig_node = container_of(rcu, struct batadv_orig_node, rcu);
217
218         spin_lock_bh(&orig_node->neigh_list_lock);
219
220         /* for all bonding members ... */
221         list_for_each_entry_safe(neigh_node, tmp_neigh_node,
222                                  &orig_node->bond_list, bonding_list) {
223                 list_del_rcu(&neigh_node->bonding_list);
224                 batadv_neigh_node_free_ref(neigh_node);
225         }
226
227         /* for all neighbors towards this originator ... */
228         hlist_for_each_entry_safe(neigh_node, node_tmp,
229                                   &orig_node->neigh_list, list) {
230                 hlist_del_rcu(&neigh_node->list);
231                 batadv_neigh_node_free_ref(neigh_node);
232         }
233
234         spin_unlock_bh(&orig_node->neigh_list_lock);
235
236         /* Free nc_nodes */
237         batadv_nc_purge_orig(orig_node->bat_priv, orig_node, NULL);
238
239         batadv_frag_purge_orig(orig_node, NULL);
240
241         batadv_tt_global_del_orig(orig_node->bat_priv, orig_node, -1,
242                                   "originator timed out");
243
244         kfree(orig_node->tt_buff);
245         kfree(orig_node->bat_iv.bcast_own);
246         kfree(orig_node->bat_iv.bcast_own_sum);
247         kfree(orig_node);
248 }
249
250 /**
251  * batadv_orig_node_free_ref - decrement the orig node refcounter and possibly
252  * schedule an rcu callback for freeing it
253  * @orig_node: the orig node to free
254  */
255 void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node)
256 {
257         if (atomic_dec_and_test(&orig_node->refcount))
258                 call_rcu(&orig_node->rcu, batadv_orig_node_free_rcu);
259 }
260
261 /**
262  * batadv_orig_node_free_ref_now - decrement the orig node refcounter and
263  * possibly free it (without rcu callback)
264  * @orig_node: the orig node to free
265  */
266 void batadv_orig_node_free_ref_now(struct batadv_orig_node *orig_node)
267 {
268         if (atomic_dec_and_test(&orig_node->refcount))
269                 batadv_orig_node_free_rcu(&orig_node->rcu);
270 }
271
272 void batadv_originator_free(struct batadv_priv *bat_priv)
273 {
274         struct batadv_hashtable *hash = bat_priv->orig_hash;
275         struct hlist_node *node_tmp;
276         struct hlist_head *head;
277         spinlock_t *list_lock; /* spinlock to protect write access */
278         struct batadv_orig_node *orig_node;
279         uint32_t i;
280
281         if (!hash)
282                 return;
283
284         cancel_delayed_work_sync(&bat_priv->orig_work);
285
286         bat_priv->orig_hash = NULL;
287
288         for (i = 0; i < hash->size; i++) {
289                 head = &hash->table[i];
290                 list_lock = &hash->list_locks[i];
291
292                 spin_lock_bh(list_lock);
293                 hlist_for_each_entry_safe(orig_node, node_tmp,
294                                           head, hash_entry) {
295                         hlist_del_rcu(&orig_node->hash_entry);
296                         batadv_orig_node_free_ref(orig_node);
297                 }
298                 spin_unlock_bh(list_lock);
299         }
300
301         batadv_hash_destroy(hash);
302 }
303
304 /**
305  * batadv_orig_node_new - creates a new orig_node
306  * @bat_priv: the bat priv with all the soft interface information
307  * @addr: the mac address of the originator
308  *
309  * Creates a new originator object and initialise all the generic fields.
310  * The new object is not added to the originator list.
311  * Returns the newly created object or NULL on failure.
312  */
313 struct batadv_orig_node *batadv_orig_node_new(struct batadv_priv *bat_priv,
314                                               const uint8_t *addr)
315 {
316         struct batadv_orig_node *orig_node;
317         struct batadv_orig_node_vlan *vlan;
318         unsigned long reset_time;
319         int i;
320
321         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
322                    "Creating new originator: %pM\n", addr);
323
324         orig_node = kzalloc(sizeof(*orig_node), GFP_ATOMIC);
325         if (!orig_node)
326                 return NULL;
327
328         INIT_HLIST_HEAD(&orig_node->neigh_list);
329         INIT_LIST_HEAD(&orig_node->bond_list);
330         INIT_LIST_HEAD(&orig_node->vlan_list);
331         spin_lock_init(&orig_node->bcast_seqno_lock);
332         spin_lock_init(&orig_node->neigh_list_lock);
333         spin_lock_init(&orig_node->tt_buff_lock);
334         spin_lock_init(&orig_node->tt_lock);
335         spin_lock_init(&orig_node->vlan_list_lock);
336
337         batadv_nc_init_orig(orig_node);
338
339         /* extra reference for return */
340         atomic_set(&orig_node->refcount, 2);
341
342         orig_node->tt_initialised = false;
343         orig_node->bat_priv = bat_priv;
344         memcpy(orig_node->orig, addr, ETH_ALEN);
345         batadv_dat_init_orig_node_addr(orig_node);
346         orig_node->router = NULL;
347         atomic_set(&orig_node->last_ttvn, 0);
348         orig_node->tt_buff = NULL;
349         orig_node->tt_buff_len = 0;
350         reset_time = jiffies - 1 - msecs_to_jiffies(BATADV_RESET_PROTECTION_MS);
351         orig_node->bcast_seqno_reset = reset_time;
352         orig_node->batman_seqno_reset = reset_time;
353
354         atomic_set(&orig_node->bond_candidates, 0);
355
356         /* create a vlan object for the "untagged" LAN */
357         vlan = batadv_orig_node_vlan_new(orig_node, BATADV_NO_FLAGS);
358         if (!vlan)
359                 goto free_orig_node;
360         /* batadv_orig_node_vlan_new() increases the refcounter.
361          * Immediately release vlan since it is not needed anymore in this
362          * context
363          */
364         batadv_orig_node_vlan_free_ref(vlan);
365
366         for (i = 0; i < BATADV_FRAG_BUFFER_COUNT; i++) {
367                 INIT_HLIST_HEAD(&orig_node->fragments[i].head);
368                 spin_lock_init(&orig_node->fragments[i].lock);
369                 orig_node->fragments[i].size = 0;
370         }
371
372         return orig_node;
373 free_orig_node:
374         kfree(orig_node);
375         return NULL;
376 }
377
378 static bool
379 batadv_purge_orig_neighbors(struct batadv_priv *bat_priv,
380                             struct batadv_orig_node *orig_node,
381                             struct batadv_neigh_node **best_neigh_node)
382 {
383         struct hlist_node *node_tmp;
384         struct batadv_neigh_node *neigh_node;
385         bool neigh_purged = false;
386         unsigned long last_seen;
387         struct batadv_hard_iface *if_incoming;
388         uint8_t best_metric = 0;
389
390         *best_neigh_node = NULL;
391
392         spin_lock_bh(&orig_node->neigh_list_lock);
393
394         /* for all neighbors towards this originator ... */
395         hlist_for_each_entry_safe(neigh_node, node_tmp,
396                                   &orig_node->neigh_list, list) {
397                 last_seen = neigh_node->last_seen;
398                 if_incoming = neigh_node->if_incoming;
399
400                 if ((batadv_has_timed_out(last_seen, BATADV_PURGE_TIMEOUT)) ||
401                     (if_incoming->if_status == BATADV_IF_INACTIVE) ||
402                     (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
403                     (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED)) {
404                         if ((if_incoming->if_status == BATADV_IF_INACTIVE) ||
405                             (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
406                             (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED))
407                                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
408                                            "neighbor purge: originator %pM, neighbor: %pM, iface: %s\n",
409                                            orig_node->orig, neigh_node->addr,
410                                            if_incoming->net_dev->name);
411                         else
412                                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
413                                            "neighbor timeout: originator %pM, neighbor: %pM, last_seen: %u\n",
414                                            orig_node->orig, neigh_node->addr,
415                                            jiffies_to_msecs(last_seen));
416
417                         neigh_purged = true;
418
419                         hlist_del_rcu(&neigh_node->list);
420                         batadv_bonding_candidate_del(orig_node, neigh_node);
421                         batadv_neigh_node_free_ref(neigh_node);
422                 } else {
423                         if ((!*best_neigh_node) ||
424                             (neigh_node->bat_iv.tq_avg > best_metric)) {
425                                 *best_neigh_node = neigh_node;
426                                 best_metric = neigh_node->bat_iv.tq_avg;
427                         }
428                 }
429         }
430
431         spin_unlock_bh(&orig_node->neigh_list_lock);
432         return neigh_purged;
433 }
434
435 static bool batadv_purge_orig_node(struct batadv_priv *bat_priv,
436                                    struct batadv_orig_node *orig_node)
437 {
438         struct batadv_neigh_node *best_neigh_node;
439
440         if (batadv_has_timed_out(orig_node->last_seen,
441                                  2 * BATADV_PURGE_TIMEOUT)) {
442                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
443                            "Originator timeout: originator %pM, last_seen %u\n",
444                            orig_node->orig,
445                            jiffies_to_msecs(orig_node->last_seen));
446                 return true;
447         } else {
448                 if (batadv_purge_orig_neighbors(bat_priv, orig_node,
449                                                 &best_neigh_node))
450                         batadv_update_route(bat_priv, orig_node,
451                                             best_neigh_node);
452         }
453
454         return false;
455 }
456
457 static void _batadv_purge_orig(struct batadv_priv *bat_priv)
458 {
459         struct batadv_hashtable *hash = bat_priv->orig_hash;
460         struct hlist_node *node_tmp;
461         struct hlist_head *head;
462         spinlock_t *list_lock; /* spinlock to protect write access */
463         struct batadv_orig_node *orig_node;
464         uint32_t i;
465
466         if (!hash)
467                 return;
468
469         /* for all origins... */
470         for (i = 0; i < hash->size; i++) {
471                 head = &hash->table[i];
472                 list_lock = &hash->list_locks[i];
473
474                 spin_lock_bh(list_lock);
475                 hlist_for_each_entry_safe(orig_node, node_tmp,
476                                           head, hash_entry) {
477                         if (batadv_purge_orig_node(bat_priv, orig_node)) {
478                                 batadv_gw_node_delete(bat_priv, orig_node);
479                                 hlist_del_rcu(&orig_node->hash_entry);
480                                 batadv_orig_node_free_ref(orig_node);
481                                 continue;
482                         }
483
484                         batadv_frag_purge_orig(orig_node,
485                                                batadv_frag_check_entry);
486                 }
487                 spin_unlock_bh(list_lock);
488         }
489
490         batadv_gw_node_purge(bat_priv);
491         batadv_gw_election(bat_priv);
492 }
493
494 static void batadv_purge_orig(struct work_struct *work)
495 {
496         struct delayed_work *delayed_work;
497         struct batadv_priv *bat_priv;
498
499         delayed_work = container_of(work, struct delayed_work, work);
500         bat_priv = container_of(delayed_work, struct batadv_priv, orig_work);
501         _batadv_purge_orig(bat_priv);
502         queue_delayed_work(batadv_event_workqueue,
503                            &bat_priv->orig_work,
504                            msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));
505 }
506
507 void batadv_purge_orig_ref(struct batadv_priv *bat_priv)
508 {
509         _batadv_purge_orig(bat_priv);
510 }
511
512 int batadv_orig_seq_print_text(struct seq_file *seq, void *offset)
513 {
514         struct net_device *net_dev = (struct net_device *)seq->private;
515         struct batadv_priv *bat_priv = netdev_priv(net_dev);
516         struct batadv_hashtable *hash = bat_priv->orig_hash;
517         struct hlist_head *head;
518         struct batadv_hard_iface *primary_if;
519         struct batadv_orig_node *orig_node;
520         struct batadv_neigh_node *neigh_node, *neigh_node_tmp;
521         int batman_count = 0;
522         int last_seen_secs;
523         int last_seen_msecs;
524         unsigned long last_seen_jiffies;
525         uint32_t i;
526
527         primary_if = batadv_seq_print_text_primary_if_get(seq);
528         if (!primary_if)
529                 goto out;
530
531         seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
532                    BATADV_SOURCE_VERSION, primary_if->net_dev->name,
533                    primary_if->net_dev->dev_addr, net_dev->name);
534         seq_printf(seq, "  %-15s %s (%s/%i) %17s [%10s]: %20s ...\n",
535                    "Originator", "last-seen", "#", BATADV_TQ_MAX_VALUE,
536                    "Nexthop", "outgoingIF", "Potential nexthops");
537
538         for (i = 0; i < hash->size; i++) {
539                 head = &hash->table[i];
540
541                 rcu_read_lock();
542                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
543                         neigh_node = batadv_orig_node_get_router(orig_node);
544                         if (!neigh_node)
545                                 continue;
546
547                         if (neigh_node->bat_iv.tq_avg == 0)
548                                 goto next;
549
550                         last_seen_jiffies = jiffies - orig_node->last_seen;
551                         last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
552                         last_seen_secs = last_seen_msecs / 1000;
553                         last_seen_msecs = last_seen_msecs % 1000;
554
555                         seq_printf(seq, "%pM %4i.%03is   (%3i) %pM [%10s]:",
556                                    orig_node->orig, last_seen_secs,
557                                    last_seen_msecs, neigh_node->bat_iv.tq_avg,
558                                    neigh_node->addr,
559                                    neigh_node->if_incoming->net_dev->name);
560
561                         hlist_for_each_entry_rcu(neigh_node_tmp,
562                                                  &orig_node->neigh_list, list) {
563                                 seq_printf(seq, " %pM (%3i)",
564                                            neigh_node_tmp->addr,
565                                            neigh_node_tmp->bat_iv.tq_avg);
566                         }
567
568                         seq_puts(seq, "\n");
569                         batman_count++;
570
571 next:
572                         batadv_neigh_node_free_ref(neigh_node);
573                 }
574                 rcu_read_unlock();
575         }
576
577         if (batman_count == 0)
578                 seq_puts(seq, "No batman nodes in range ...\n");
579
580 out:
581         if (primary_if)
582                 batadv_hardif_free_ref(primary_if);
583         return 0;
584 }
585
586 static int batadv_orig_node_add_if(struct batadv_orig_node *orig_node,
587                                    int max_if_num)
588 {
589         void *data_ptr;
590         size_t data_size, old_size;
591
592         data_size = max_if_num * sizeof(unsigned long) * BATADV_NUM_WORDS;
593         old_size = (max_if_num - 1) * sizeof(unsigned long) * BATADV_NUM_WORDS;
594         data_ptr = kmalloc(data_size, GFP_ATOMIC);
595         if (!data_ptr)
596                 return -ENOMEM;
597
598         memcpy(data_ptr, orig_node->bat_iv.bcast_own, old_size);
599         kfree(orig_node->bat_iv.bcast_own);
600         orig_node->bat_iv.bcast_own = data_ptr;
601
602         data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
603         if (!data_ptr)
604                 return -ENOMEM;
605
606         memcpy(data_ptr, orig_node->bat_iv.bcast_own_sum,
607                (max_if_num - 1) * sizeof(uint8_t));
608         kfree(orig_node->bat_iv.bcast_own_sum);
609         orig_node->bat_iv.bcast_own_sum = data_ptr;
610
611         return 0;
612 }
613
614 int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface,
615                             int max_if_num)
616 {
617         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
618         struct batadv_hashtable *hash = bat_priv->orig_hash;
619         struct hlist_head *head;
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->bat_iv.ogm_cnt_lock);
633                         ret = batadv_orig_node_add_if(orig_node, max_if_num);
634                         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
635
636                         if (ret == -ENOMEM)
637                                 goto err;
638                 }
639                 rcu_read_unlock();
640         }
641
642         return 0;
643
644 err:
645         rcu_read_unlock();
646         return -ENOMEM;
647 }
648
649 static int batadv_orig_node_del_if(struct batadv_orig_node *orig_node,
650                                    int max_if_num, int del_if_num)
651 {
652         int chunk_size, if_offset;
653         void *data_ptr = NULL;
654
655         /* last interface was removed */
656         if (max_if_num == 0)
657                 goto free_bcast_own;
658
659         chunk_size = sizeof(unsigned long) * BATADV_NUM_WORDS;
660         data_ptr = kmalloc(max_if_num * chunk_size, GFP_ATOMIC);
661         if (!data_ptr)
662                 return -ENOMEM;
663
664         /* copy first part */
665         memcpy(data_ptr, orig_node->bat_iv.bcast_own, del_if_num * chunk_size);
666
667         /* copy second part */
668         memcpy((char *)data_ptr + del_if_num * chunk_size,
669                orig_node->bat_iv.bcast_own + ((del_if_num + 1) * chunk_size),
670                (max_if_num - del_if_num) * chunk_size);
671
672 free_bcast_own:
673         kfree(orig_node->bat_iv.bcast_own);
674         orig_node->bat_iv.bcast_own = data_ptr;
675
676         if (max_if_num == 0)
677                 goto free_own_sum;
678
679         data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
680         if (!data_ptr)
681                 return -ENOMEM;
682
683         memcpy(data_ptr, orig_node->bat_iv.bcast_own_sum,
684                del_if_num * sizeof(uint8_t));
685
686         if_offset = (del_if_num + 1) * sizeof(uint8_t);
687         memcpy((char *)data_ptr + del_if_num * sizeof(uint8_t),
688                orig_node->bat_iv.bcast_own_sum + if_offset,
689                (max_if_num - del_if_num) * sizeof(uint8_t));
690
691 free_own_sum:
692         kfree(orig_node->bat_iv.bcast_own_sum);
693         orig_node->bat_iv.bcast_own_sum = data_ptr;
694
695         return 0;
696 }
697
698 int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface,
699                             int max_if_num)
700 {
701         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
702         struct batadv_hashtable *hash = bat_priv->orig_hash;
703         struct hlist_head *head;
704         struct batadv_hard_iface *hard_iface_tmp;
705         struct batadv_orig_node *orig_node;
706         uint32_t i;
707         int ret;
708
709         /* resize all orig nodes because orig_node->bcast_own(_sum) depend on
710          * if_num
711          */
712         for (i = 0; i < hash->size; i++) {
713                 head = &hash->table[i];
714
715                 rcu_read_lock();
716                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
717                         spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
718                         ret = batadv_orig_node_del_if(orig_node, max_if_num,
719                                                       hard_iface->if_num);
720                         spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
721
722                         if (ret == -ENOMEM)
723                                 goto err;
724                 }
725                 rcu_read_unlock();
726         }
727
728         /* renumber remaining batman interfaces _inside_ of orig_hash_lock */
729         rcu_read_lock();
730         list_for_each_entry_rcu(hard_iface_tmp, &batadv_hardif_list, list) {
731                 if (hard_iface_tmp->if_status == BATADV_IF_NOT_IN_USE)
732                         continue;
733
734                 if (hard_iface == hard_iface_tmp)
735                         continue;
736
737                 if (hard_iface->soft_iface != hard_iface_tmp->soft_iface)
738                         continue;
739
740                 if (hard_iface_tmp->if_num > hard_iface->if_num)
741                         hard_iface_tmp->if_num--;
742         }
743         rcu_read_unlock();
744
745         hard_iface->if_num = -1;
746         return 0;
747
748 err:
749         rcu_read_unlock();
750         return -ENOMEM;
751 }