net/batman-adv/originator.c

   1 /* Copyright (C) 2009-2012 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 "originator.h"
  22 #include "hash.h"
  23 #include "translation-table.h"
  24 #include "routing.h"
  25 #include "gateway_client.h"
  26 #include "hard-interface.h"
  27 #include "unicast.h"
  28 #include "soft-interface.h"
  29 #include "bridge_loop_avoidance.h"
  30
  31 static void batadv_purge_orig(struct work_struct *work);
  32
  33 static void batadv_start_purge_timer(struct batadv_priv *bat_priv)
  34 {
  35         INIT_DELAYED_WORK(&bat_priv->orig_work, batadv_purge_orig);
  36         queue_delayed_work(batadv_event_workqueue,
  37                            &bat_priv->orig_work, msecs_to_jiffies(1000));
  38 }
  39
  40 /* returns 1 if they are the same originator */
  41 static int batadv_compare_orig(const struct hlist_node *node, const void *data2)
  42 {
  43         const void *data1 = container_of(node, struct batadv_orig_node,
  44                                          hash_entry);
  45
  46         return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
  47 }
  48
  49 int batadv_originator_init(struct batadv_priv *bat_priv)
  50 {
  51         if (bat_priv->orig_hash)
  52                 return 0;
  53
  54         bat_priv->orig_hash = batadv_hash_new(1024);
  55
  56         if (!bat_priv->orig_hash)
  57                 goto err;
  58
  59         batadv_start_purge_timer(bat_priv);
  60         return 0;
  61
  62 err:
  63         return -ENOMEM;
  64 }
  65
  66 void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node)
  67 {
  68         if (atomic_dec_and_test(&neigh_node->refcount))
  69                 kfree_rcu(neigh_node, rcu);
  70 }
  71
  72 /* increases the refcounter of a found router */
  73 struct batadv_neigh_node *
  74 batadv_orig_node_get_router(struct batadv_orig_node *orig_node)
  75 {
  76         struct batadv_neigh_node *router;
  77
  78         rcu_read_lock();
  79         router = rcu_dereference(orig_node->router);
  80
  81         if (router && !atomic_inc_not_zero(&router->refcount))
  82                 router = NULL;
  83
  84         rcu_read_unlock();
  85         return router;
  86 }
  87
  88 struct batadv_neigh_node *
  89 batadv_neigh_node_new(struct batadv_hard_iface *hard_iface,
  90                       const uint8_t *neigh_addr, uint32_t seqno)
  91 {
  92         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
  93         struct batadv_neigh_node *neigh_node;
  94
  95         neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC);
  96         if (!neigh_node)
  97                 goto out;
  98
  99         INIT_HLIST_NODE(&neigh_node->list);
 100
 101         memcpy(neigh_node->addr, neigh_addr, ETH_ALEN);
 102         spin_lock_init(&neigh_node->lq_update_lock);
 103
 104         /* extra reference for return */
 105         atomic_set(&neigh_node->refcount, 2);
 106
 107         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 108                    "Creating new neighbor %pM, initial seqno %d\n",
 109                    neigh_addr, seqno);
 110
 111 out:
 112         return neigh_node;
 113 }
 114
 115 static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
 116 {
 117         struct hlist_node *node, *node_tmp;
 118         struct batadv_neigh_node *neigh_node, *tmp_neigh_node;
 119         struct batadv_orig_node *orig_node;
 120
 121         orig_node = container_of(rcu, struct batadv_orig_node, rcu);
 122
 123         spin_lock_bh(&orig_node->neigh_list_lock);
 124
 125         /* for all bonding members ... */
 126         list_for_each_entry_safe(neigh_node, tmp_neigh_node,
 127                                  &orig_node->bond_list, bonding_list) {
 128                 list_del_rcu(&neigh_node->bonding_list);
 129                 batadv_neigh_node_free_ref(neigh_node);
 130         }
 131
 132         /* for all neighbors towards this originator ... */
 133         hlist_for_each_entry_safe(neigh_node, node, node_tmp,
 134                                   &orig_node->neigh_list, list) {
 135                 hlist_del_rcu(&neigh_node->list);
 136                 batadv_neigh_node_free_ref(neigh_node);
 137         }
 138
 139         spin_unlock_bh(&orig_node->neigh_list_lock);
 140
 141         batadv_frag_list_free(&orig_node->frag_list);
 142         batadv_tt_global_del_orig(orig_node->bat_priv, orig_node,
 143                                   "originator timed out");
 144
 145         kfree(orig_node->tt_buff);
 146         kfree(orig_node->bcast_own);
 147         kfree(orig_node->bcast_own_sum);
 148         kfree(orig_node);
 149 }
 150
 151 void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node)
 152 {
 153         if (atomic_dec_and_test(&orig_node->refcount))
 154                 call_rcu(&orig_node->rcu, batadv_orig_node_free_rcu);
 155 }
 156
 157 void batadv_originator_free(struct batadv_priv *bat_priv)
 158 {
 159         struct batadv_hashtable *hash = bat_priv->orig_hash;
 160         struct hlist_node *node, *node_tmp;
 161         struct hlist_head *head;
 162         spinlock_t *list_lock; /* spinlock to protect write access */
 163         struct batadv_orig_node *orig_node;
 164         uint32_t i;
 165
 166         if (!hash)
 167                 return;
 168
 169         cancel_delayed_work_sync(&bat_priv->orig_work);
 170
 171         bat_priv->orig_hash = NULL;
 172
 173         for (i = 0; i < hash->size; i++) {
 174                 head = &hash->table[i];
 175                 list_lock = &hash->list_locks[i];
 176
 177                 spin_lock_bh(list_lock);
 178                 hlist_for_each_entry_safe(orig_node, node, node_tmp,
 179                                           head, hash_entry) {
 180
 181                         hlist_del_rcu(node);
 182                         batadv_orig_node_free_ref(orig_node);
 183                 }
 184                 spin_unlock_bh(list_lock);
 185         }
 186
 187         batadv_hash_destroy(hash);
 188 }
 189
 190 /* this function finds or creates an originator entry for the given
 191  * address if it does not exits
 192  */
 193 struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv,
 194                                               const uint8_t *addr)
 195 {
 196         struct batadv_orig_node *orig_node;
 197         int size;
 198         int hash_added;
 199         unsigned long reset_time;
 200
 201         orig_node = batadv_orig_hash_find(bat_priv, addr);
 202         if (orig_node)
 203                 return orig_node;
 204
 205         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 206                    "Creating new originator: %pM\n", addr);
 207
 208         orig_node = kzalloc(sizeof(*orig_node), GFP_ATOMIC);
 209         if (!orig_node)
 210                 return NULL;
 211
 212         INIT_HLIST_HEAD(&orig_node->neigh_list);
 213         INIT_LIST_HEAD(&orig_node->bond_list);
 214         spin_lock_init(&orig_node->ogm_cnt_lock);
 215         spin_lock_init(&orig_node->bcast_seqno_lock);
 216         spin_lock_init(&orig_node->neigh_list_lock);
 217         spin_lock_init(&orig_node->tt_buff_lock);
 218
 219         /* extra reference for return */
 220         atomic_set(&orig_node->refcount, 2);
 221
 222         orig_node->tt_initialised = false;
 223         orig_node->tt_poss_change = false;
 224         orig_node->bat_priv = bat_priv;
 225         memcpy(orig_node->orig, addr, ETH_ALEN);
 226         orig_node->router = NULL;
 227         orig_node->tt_crc = 0;
 228         atomic_set(&orig_node->last_ttvn, 0);
 229         orig_node->tt_buff = NULL;
 230         orig_node->tt_buff_len = 0;
 231         atomic_set(&orig_node->tt_size, 0);
 232         reset_time = jiffies - 1 - msecs_to_jiffies(BATADV_RESET_PROTECTION_MS);
 233         orig_node->bcast_seqno_reset = reset_time;
 234         orig_node->batman_seqno_reset = reset_time;
 235
 236         atomic_set(&orig_node->bond_candidates, 0);
 237
 238         size = bat_priv->num_ifaces * sizeof(unsigned long) * BATADV_NUM_WORDS;
 239
 240         orig_node->bcast_own = kzalloc(size, GFP_ATOMIC);
 241         if (!orig_node->bcast_own)
 242                 goto free_orig_node;
 243
 244         size = bat_priv->num_ifaces * sizeof(uint8_t);
 245         orig_node->bcast_own_sum = kzalloc(size, GFP_ATOMIC);
 246
 247         INIT_LIST_HEAD(&orig_node->frag_list);
 248         orig_node->last_frag_packet = 0;
 249
 250         if (!orig_node->bcast_own_sum)
 251                 goto free_bcast_own;
 252
 253         hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
 254                                      batadv_choose_orig, orig_node,
 255                                      &orig_node->hash_entry);
 256         if (hash_added != 0)
 257                 goto free_bcast_own_sum;
 258
 259         return orig_node;
 260 free_bcast_own_sum:
 261         kfree(orig_node->bcast_own_sum);
 262 free_bcast_own:
 263         kfree(orig_node->bcast_own);
 264 free_orig_node:
 265         kfree(orig_node);
 266         return NULL;
 267 }
 268
 269 static bool
 270 batadv_purge_orig_neighbors(struct batadv_priv *bat_priv,
 271                             struct batadv_orig_node *orig_node,
 272                             struct batadv_neigh_node **best_neigh_node)
 273 {
 274         struct hlist_node *node, *node_tmp;
 275         struct batadv_neigh_node *neigh_node;
 276         bool neigh_purged = false;
 277         unsigned long last_seen;
 278         struct batadv_hard_iface *if_incoming;
 279
 280         *best_neigh_node = NULL;
 281
 282         spin_lock_bh(&orig_node->neigh_list_lock);
 283
 284         /* for all neighbors towards this originator ... */
 285         hlist_for_each_entry_safe(neigh_node, node, node_tmp,
 286                                   &orig_node->neigh_list, list) {
 287
 288                 last_seen = neigh_node->last_seen;
 289                 if_incoming = neigh_node->if_incoming;
 290
 291                 if ((batadv_has_timed_out(last_seen, BATADV_PURGE_TIMEOUT)) ||
 292                     (if_incoming->if_status == BATADV_IF_INACTIVE) ||
 293                     (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
 294                     (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED)) {
 295
 296                         if ((if_incoming->if_status == BATADV_IF_INACTIVE) ||
 297                             (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
 298                             (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED))
 299                                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 300                                            "neighbor purge: originator %pM, neighbor: %pM, iface: %s\n",
 301                                            orig_node->orig, neigh_node->addr,
 302                                            if_incoming->net_dev->name);
 303                         else
 304                                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 305                                            "neighbor timeout: originator %pM, neighbor: %pM, last_seen: %u\n",
 306                                            orig_node->orig, neigh_node->addr,
 307                                            jiffies_to_msecs(last_seen));
 308
 309                         neigh_purged = true;
 310
 311                         hlist_del_rcu(&neigh_node->list);
 312                         batadv_bonding_candidate_del(orig_node, neigh_node);
 313                         batadv_neigh_node_free_ref(neigh_node);
 314                 } else {
 315                         if ((!*best_neigh_node) ||
 316                             (neigh_node->tq_avg > (*best_neigh_node)->tq_avg))
 317                                 *best_neigh_node = neigh_node;
 318                 }
 319         }
 320
 321         spin_unlock_bh(&orig_node->neigh_list_lock);
 322         return neigh_purged;
 323 }
 324
 325 static bool batadv_purge_orig_node(struct batadv_priv *bat_priv,
 326                                    struct batadv_orig_node *orig_node)
 327 {
 328         struct batadv_neigh_node *best_neigh_node;
 329
 330         if (batadv_has_timed_out(orig_node->last_seen,
 331                                  2 * BATADV_PURGE_TIMEOUT)) {
 332                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 333                            "Originator timeout: originator %pM, last_seen %u\n",
 334                            orig_node->orig,
 335                            jiffies_to_msecs(orig_node->last_seen));
 336                 return true;
 337         } else {
 338                 if (batadv_purge_orig_neighbors(bat_priv, orig_node,
 339                                                 &best_neigh_node))
 340                         batadv_update_route(bat_priv, orig_node,
 341                                             best_neigh_node);
 342         }
 343
 344         return false;
 345 }
 346
 347 static void _batadv_purge_orig(struct batadv_priv *bat_priv)
 348 {
 349         struct batadv_hashtable *hash = bat_priv->orig_hash;
 350         struct hlist_node *node, *node_tmp;
 351         struct hlist_head *head;
 352         spinlock_t *list_lock; /* spinlock to protect write access */
 353         struct batadv_orig_node *orig_node;
 354         uint32_t i;
 355
 356         if (!hash)
 357                 return;
 358
 359         /* for all origins... */
 360         for (i = 0; i < hash->size; i++) {
 361                 head = &hash->table[i];
 362                 list_lock = &hash->list_locks[i];
 363
 364                 spin_lock_bh(list_lock);
 365                 hlist_for_each_entry_safe(orig_node, node, node_tmp,
 366                                           head, hash_entry) {
 367                         if (batadv_purge_orig_node(bat_priv, orig_node)) {
 368                                 if (orig_node->gw_flags)
 369                                         batadv_gw_node_delete(bat_priv,
 370                                                               orig_node);
 371                                 hlist_del_rcu(node);
 372                                 batadv_orig_node_free_ref(orig_node);
 373                                 continue;
 374                         }
 375
 376                         if (batadv_has_timed_out(orig_node->last_frag_packet,
 377                                                  BATADV_FRAG_TIMEOUT))
 378                                 batadv_frag_list_free(&orig_node->frag_list);
 379                 }
 380                 spin_unlock_bh(list_lock);
 381         }
 382
 383         batadv_gw_node_purge(bat_priv);
 384         batadv_gw_election(bat_priv);
 385 }
 386
 387 static void batadv_purge_orig(struct work_struct *work)
 388 {
 389         struct delayed_work *delayed_work;
 390         struct batadv_priv *bat_priv;
 391
 392         delayed_work = container_of(work, struct delayed_work, work);
 393         bat_priv = container_of(delayed_work, struct batadv_priv, orig_work);
 394         _batadv_purge_orig(bat_priv);
 395         batadv_start_purge_timer(bat_priv);
 396 }
 397
 398 void batadv_purge_orig_ref(struct batadv_priv *bat_priv)
 399 {
 400         _batadv_purge_orig(bat_priv);
 401 }
 402
 403 int batadv_orig_seq_print_text(struct seq_file *seq, void *offset)
 404 {
 405         struct net_device *net_dev = (struct net_device *)seq->private;
 406         struct batadv_priv *bat_priv = netdev_priv(net_dev);
 407         struct batadv_hashtable *hash = bat_priv->orig_hash;
 408         struct hlist_node *node, *node_tmp;
 409         struct hlist_head *head;
 410         struct batadv_hard_iface *primary_if;
 411         struct batadv_orig_node *orig_node;
 412         struct batadv_neigh_node *neigh_node, *neigh_node_tmp;
 413         int batman_count = 0;
 414         int last_seen_secs;
 415         int last_seen_msecs;
 416         unsigned long last_seen_jiffies;
 417         uint32_t i;
 418         int ret = 0;
 419
 420         primary_if = batadv_primary_if_get_selected(bat_priv);
 421
 422         if (!primary_if) {
 423                 ret = seq_printf(seq,
 424                                  "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
 425                                  net_dev->name);
 426                 goto out;
 427         }
 428
 429         if (primary_if->if_status != BATADV_IF_ACTIVE) {
 430                 ret = seq_printf(seq,
 431                                  "BATMAN mesh %s disabled - primary interface not active\n",
 432                                  net_dev->name);
 433                 goto out;
 434         }
 435
 436         seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
 437                    BATADV_SOURCE_VERSION, primary_if->net_dev->name,
 438                    primary_if->net_dev->dev_addr, net_dev->name);
 439         seq_printf(seq, "  %-15s %s (%s/%i) %17s [%10s]: %20s ...\n",
 440                    "Originator", "last-seen", "#", BATADV_TQ_MAX_VALUE,
 441                    "Nexthop", "outgoingIF", "Potential nexthops");
 442
 443         for (i = 0; i < hash->size; i++) {
 444                 head = &hash->table[i];
 445
 446                 rcu_read_lock();
 447                 hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
 448                         neigh_node = batadv_orig_node_get_router(orig_node);
 449                         if (!neigh_node)
 450                                 continue;
 451
 452                         if (neigh_node->tq_avg == 0)
 453                                 goto next;
 454
 455                         last_seen_jiffies = jiffies - orig_node->last_seen;
 456                         last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
 457                         last_seen_secs = last_seen_msecs / 1000;
 458                         last_seen_msecs = last_seen_msecs % 1000;
 459
 460                         seq_printf(seq, "%pM %4i.%03is   (%3i) %pM [%10s]:",
 461                                    orig_node->orig, last_seen_secs,
 462                                    last_seen_msecs, neigh_node->tq_avg,
 463                                    neigh_node->addr,
 464                                    neigh_node->if_incoming->net_dev->name);
 465
 466                         hlist_for_each_entry_rcu(neigh_node_tmp, node_tmp,
 467                                                  &orig_node->neigh_list, list) {
 468                                 seq_printf(seq, " %pM (%3i)",
 469                                            neigh_node_tmp->addr,
 470                                            neigh_node_tmp->tq_avg);
 471                         }
 472
 473                         seq_printf(seq, "\n");
 474                         batman_count++;
 475
 476 next:
 477                         batadv_neigh_node_free_ref(neigh_node);
 478                 }
 479                 rcu_read_unlock();
 480         }
 481
 482         if (batman_count == 0)
 483                 seq_printf(seq, "No batman nodes in range ...\n");
 484
 485 out:
 486         if (primary_if)
 487                 batadv_hardif_free_ref(primary_if);
 488         return ret;
 489 }
 490
 491 static int batadv_orig_node_add_if(struct batadv_orig_node *orig_node,
 492                                    int max_if_num)
 493 {
 494         void *data_ptr;
 495         size_t data_size, old_size;
 496
 497         data_size = max_if_num * sizeof(unsigned long) * BATADV_NUM_WORDS;
 498         old_size = (max_if_num - 1) * sizeof(unsigned long) * BATADV_NUM_WORDS;
 499         data_ptr = kmalloc(data_size, GFP_ATOMIC);
 500         if (!data_ptr)
 501                 return -ENOMEM;
 502
 503         memcpy(data_ptr, orig_node->bcast_own, old_size);
 504         kfree(orig_node->bcast_own);
 505         orig_node->bcast_own = data_ptr;
 506
 507         data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
 508         if (!data_ptr)
 509                 return -ENOMEM;
 510
 511         memcpy(data_ptr, orig_node->bcast_own_sum,
 512                (max_if_num - 1) * sizeof(uint8_t));
 513         kfree(orig_node->bcast_own_sum);
 514         orig_node->bcast_own_sum = data_ptr;
 515
 516         return 0;
 517 }
 518
 519 int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface,
 520                             int max_if_num)
 521 {
 522         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 523         struct batadv_hashtable *hash = bat_priv->orig_hash;
 524         struct hlist_node *node;
 525         struct hlist_head *head;
 526         struct batadv_orig_node *orig_node;
 527         uint32_t i;
 528         int ret;
 529
 530         /* resize all orig nodes because orig_node->bcast_own(_sum) depend on
 531          * if_num
 532          */
 533         for (i = 0; i < hash->size; i++) {
 534                 head = &hash->table[i];
 535
 536                 rcu_read_lock();
 537                 hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
 538                         spin_lock_bh(&orig_node->ogm_cnt_lock);
 539                         ret = batadv_orig_node_add_if(orig_node, max_if_num);
 540                         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 541
 542                         if (ret == -ENOMEM)
 543                                 goto err;
 544                 }
 545                 rcu_read_unlock();
 546         }
 547
 548         return 0;
 549
 550 err:
 551         rcu_read_unlock();
 552         return -ENOMEM;
 553 }
 554
 555 static int batadv_orig_node_del_if(struct batadv_orig_node *orig_node,
 556                                    int max_if_num, int del_if_num)
 557 {
 558         void *data_ptr = NULL;
 559         int chunk_size;
 560
 561         /* last interface was removed */
 562         if (max_if_num == 0)
 563                 goto free_bcast_own;
 564
 565         chunk_size = sizeof(unsigned long) * BATADV_NUM_WORDS;
 566         data_ptr = kmalloc(max_if_num * chunk_size, GFP_ATOMIC);
 567         if (!data_ptr)
 568                 return -ENOMEM;
 569
 570         /* copy first part */
 571         memcpy(data_ptr, orig_node->bcast_own, del_if_num * chunk_size);
 572
 573         /* copy second part */
 574         memcpy((char *)data_ptr + del_if_num * chunk_size,
 575                orig_node->bcast_own + ((del_if_num + 1) * chunk_size),
 576                (max_if_num - del_if_num) * chunk_size);
 577
 578 free_bcast_own:
 579         kfree(orig_node->bcast_own);
 580         orig_node->bcast_own = data_ptr;
 581
 582         if (max_if_num == 0)
 583                 goto free_own_sum;
 584
 585         data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
 586         if (!data_ptr)
 587                 return -ENOMEM;
 588
 589         memcpy(data_ptr, orig_node->bcast_own_sum,
 590                del_if_num * sizeof(uint8_t));
 591
 592         memcpy((char *)data_ptr + del_if_num * sizeof(uint8_t),
 593                orig_node->bcast_own_sum + ((del_if_num + 1) * sizeof(uint8_t)),
 594                (max_if_num - del_if_num) * sizeof(uint8_t));
 595
 596 free_own_sum:
 597         kfree(orig_node->bcast_own_sum);
 598         orig_node->bcast_own_sum = data_ptr;
 599
 600         return 0;
 601 }
 602
 603 int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface,
 604                             int max_if_num)
 605 {
 606         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 607         struct batadv_hashtable *hash = bat_priv->orig_hash;
 608         struct hlist_node *node;
 609         struct hlist_head *head;
 610         struct batadv_hard_iface *hard_iface_tmp;
 611         struct batadv_orig_node *orig_node;
 612         uint32_t i;
 613         int ret;
 614
 615         /* resize all orig nodes because orig_node->bcast_own(_sum) depend on
 616          * if_num
 617          */
 618         for (i = 0; i < hash->size; i++) {
 619                 head = &hash->table[i];
 620
 621                 rcu_read_lock();
 622                 hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
 623                         spin_lock_bh(&orig_node->ogm_cnt_lock);
 624                         ret = batadv_orig_node_del_if(orig_node, max_if_num,
 625                                                       hard_iface->if_num);
 626                         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 627
 628                         if (ret == -ENOMEM)
 629                                 goto err;
 630                 }
 631                 rcu_read_unlock();
 632         }
 633
 634         /* renumber remaining batman interfaces _inside_ of orig_hash_lock */
 635         rcu_read_lock();
 636         list_for_each_entry_rcu(hard_iface_tmp, &batadv_hardif_list, list) {
 637                 if (hard_iface_tmp->if_status == BATADV_IF_NOT_IN_USE)
 638                         continue;
 639
 640                 if (hard_iface == hard_iface_tmp)
 641                         continue;
 642
 643                 if (hard_iface->soft_iface != hard_iface_tmp->soft_iface)
 644                         continue;
 645
 646                 if (hard_iface_tmp->if_num > hard_iface->if_num)
 647                         hard_iface_tmp->if_num--;
 648         }
 649         rcu_read_unlock();
 650
 651         hard_iface->if_num = -1;
 652         return 0;
 653
 654 err:
 655         rcu_read_unlock();
 656         return -ENOMEM;
 657 }