net/batman-adv/send.c

   1 /*
   2  * Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  *
  20  */
  21
  22 #include "main.h"
  23 #include "send.h"
  24 #include "routing.h"
  25 #include "translation-table.h"
  26 #include "soft-interface.h"
  27 #include "hard-interface.h"
  28 #include "vis.h"
  29 #include "aggregation.h"
  30 #include "gateway_common.h"
  31 #include "originator.h"
  32
  33 static void send_outstanding_bcast_packet(struct work_struct *work);
  34
  35 /* apply hop penalty for a normal link */
  36 static uint8_t hop_penalty(uint8_t tq, const struct bat_priv *bat_priv)
  37 {
  38         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
  39         return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
  40 }
  41
  42 /* when do we schedule our own packet to be sent */
  43 static unsigned long own_send_time(const struct bat_priv *bat_priv)
  44 {
  45         return jiffies + msecs_to_jiffies(
  46                    atomic_read(&bat_priv->orig_interval) -
  47                    JITTER + (random32() % 2*JITTER));
  48 }
  49
  50 /* when do we schedule a forwarded packet to be sent */
  51 static unsigned long forward_send_time(void)
  52 {
  53         return jiffies + msecs_to_jiffies(random32() % (JITTER/2));
  54 }
  55
  56 /* send out an already prepared packet to the given address via the
  57  * specified batman interface */
  58 int send_skb_packet(struct sk_buff *skb, struct hard_iface *hard_iface,
  59                     const uint8_t *dst_addr)
  60 {
  61         struct ethhdr *ethhdr;
  62
  63         if (hard_iface->if_status != IF_ACTIVE)
  64                 goto send_skb_err;
  65
  66         if (unlikely(!hard_iface->net_dev))
  67                 goto send_skb_err;
  68
  69         if (!(hard_iface->net_dev->flags & IFF_UP)) {
  70                 pr_warning("Interface %s is not up - can't send packet via "
  71                            "that interface!\n", hard_iface->net_dev->name);
  72                 goto send_skb_err;
  73         }
  74
  75         /* push to the ethernet header. */
  76         if (my_skb_head_push(skb, sizeof(*ethhdr)) < 0)
  77                 goto send_skb_err;
  78
  79         skb_reset_mac_header(skb);
  80
  81         ethhdr = (struct ethhdr *) skb_mac_header(skb);
  82         memcpy(ethhdr->h_source, hard_iface->net_dev->dev_addr, ETH_ALEN);
  83         memcpy(ethhdr->h_dest, dst_addr, ETH_ALEN);
  84         ethhdr->h_proto = __constant_htons(ETH_P_BATMAN);
  85
  86         skb_set_network_header(skb, ETH_HLEN);
  87         skb->priority = TC_PRIO_CONTROL;
  88         skb->protocol = __constant_htons(ETH_P_BATMAN);
  89
  90         skb->dev = hard_iface->net_dev;
  91
  92         /* dev_queue_xmit() returns a negative result on error.  However on
  93          * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
  94          * (which is > 0). This will not be treated as an error. */
  95
  96         return dev_queue_xmit(skb);
  97 send_skb_err:
  98         kfree_skb(skb);
  99         return NET_XMIT_DROP;
 100 }
 101
 102 /* Send a packet to a given interface */
 103 static void send_packet_to_if(struct forw_packet *forw_packet,
 104                               struct hard_iface *hard_iface)
 105 {
 106         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 107         char *fwd_str;
 108         uint8_t packet_num;
 109         int16_t buff_pos;
 110         struct batman_packet *batman_packet;
 111         struct sk_buff *skb;
 112
 113         if (hard_iface->if_status != IF_ACTIVE)
 114                 return;
 115
 116         packet_num = 0;
 117         buff_pos = 0;
 118         batman_packet = (struct batman_packet *)forw_packet->skb->data;
 119
 120         /* adjust all flags and log packets */
 121         while (aggregated_packet(buff_pos,
 122                                  forw_packet->packet_len,
 123                                  batman_packet->tt_num_changes)) {
 124
 125                 /* we might have aggregated direct link packets with an
 126                  * ordinary base packet */
 127                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 128                     (forw_packet->if_incoming == hard_iface))
 129                         batman_packet->flags |= DIRECTLINK;
 130                 else
 131                         batman_packet->flags &= ~DIRECTLINK;
 132
 133                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 134                                                             "Sending own" :
 135                                                             "Forwarding"));
 136                 bat_dbg(DBG_BATMAN, bat_priv,
 137                         "%s %spacket (originator %pM, seqno %d, TQ %d, TTL %d,"
 138                         " IDF %s, hvn %d) on interface %s [%pM]\n",
 139                         fwd_str, (packet_num > 0 ? "aggregated " : ""),
 140                         batman_packet->orig, ntohl(batman_packet->seqno),
 141                         batman_packet->tq, batman_packet->ttl,
 142                         (batman_packet->flags & DIRECTLINK ?
 143                          "on" : "off"),
 144                         batman_packet->ttvn, hard_iface->net_dev->name,
 145                         hard_iface->net_dev->dev_addr);
 146
 147                 buff_pos += sizeof(*batman_packet) +
 148                         tt_len(batman_packet->tt_num_changes);
 149                 packet_num++;
 150                 batman_packet = (struct batman_packet *)
 151                         (forw_packet->skb->data + buff_pos);
 152         }
 153
 154         /* create clone because function is called more than once */
 155         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 156         if (skb)
 157                 send_skb_packet(skb, hard_iface, broadcast_addr);
 158 }
 159
 160 /* send a batman packet */
 161 static void send_packet(struct forw_packet *forw_packet)
 162 {
 163         struct hard_iface *hard_iface;
 164         struct net_device *soft_iface;
 165         struct bat_priv *bat_priv;
 166         struct batman_packet *batman_packet =
 167                 (struct batman_packet *)(forw_packet->skb->data);
 168         int directlink = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 169
 170         if (!forw_packet->if_incoming) {
 171                 pr_err("Error - can't forward packet: incoming iface not "
 172                        "specified\n");
 173                 return;
 174         }
 175
 176         soft_iface = forw_packet->if_incoming->soft_iface;
 177         bat_priv = netdev_priv(soft_iface);
 178
 179         if (forw_packet->if_incoming->if_status != IF_ACTIVE)
 180                 return;
 181
 182         /* multihomed peer assumed */
 183         /* non-primary OGMs are only broadcasted on their interface */
 184         if ((directlink && (batman_packet->ttl == 1)) ||
 185             (forw_packet->own && (forw_packet->if_incoming->if_num > 0))) {
 186
 187                 /* FIXME: what about aggregated packets ? */
 188                 bat_dbg(DBG_BATMAN, bat_priv,
 189                         "%s packet (originator %pM, seqno %d, TTL %d) "
 190                         "on interface %s [%pM]\n",
 191                         (forw_packet->own ? "Sending own" : "Forwarding"),
 192                         batman_packet->orig, ntohl(batman_packet->seqno),
 193                         batman_packet->ttl,
 194                         forw_packet->if_incoming->net_dev->name,
 195                         forw_packet->if_incoming->net_dev->dev_addr);
 196
 197                 /* skb is only used once and than forw_packet is free'd */
 198                 send_skb_packet(forw_packet->skb, forw_packet->if_incoming,
 199                                 broadcast_addr);
 200                 forw_packet->skb = NULL;
 201
 202                 return;
 203         }
 204
 205         /* broadcast on every interface */
 206         rcu_read_lock();
 207         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 208                 if (hard_iface->soft_iface != soft_iface)
 209                         continue;
 210
 211                 send_packet_to_if(forw_packet, hard_iface);
 212         }
 213         rcu_read_unlock();
 214 }
 215
 216 static void realloc_packet_buffer(struct hard_iface *hard_iface,
 217                                 int new_len)
 218 {
 219         unsigned char *new_buff;
 220         struct batman_packet *batman_packet;
 221
 222         new_buff = kmalloc(new_len, GFP_ATOMIC);
 223
 224         /* keep old buffer if kmalloc should fail */
 225         if (new_buff) {
 226                 memcpy(new_buff, hard_iface->packet_buff,
 227                        sizeof(*batman_packet));
 228
 229                 kfree(hard_iface->packet_buff);
 230                 hard_iface->packet_buff = new_buff;
 231                 hard_iface->packet_len = new_len;
 232         }
 233 }
 234
 235 /* when calling this function (hard_iface == primary_if) has to be true */
 236 static void prepare_packet_buffer(struct bat_priv *bat_priv,
 237                                   struct hard_iface *hard_iface)
 238 {
 239         int new_len;
 240         struct batman_packet *batman_packet;
 241
 242         new_len = BAT_PACKET_LEN +
 243                   tt_len((uint8_t)atomic_read(&bat_priv->tt_local_changes));
 244
 245         /* if we have too many changes for one packet don't send any
 246          * and wait for the tt table request which will be fragmented */
 247         if (new_len > hard_iface->soft_iface->mtu)
 248                 new_len = BAT_PACKET_LEN;
 249
 250         realloc_packet_buffer(hard_iface, new_len);
 251         batman_packet = (struct batman_packet *)hard_iface->packet_buff;
 252
 253         atomic_set(&bat_priv->tt_crc, tt_local_crc(bat_priv));
 254
 255         /* reset the sending counter */
 256         atomic_set(&bat_priv->tt_ogm_append_cnt, TT_OGM_APPEND_MAX);
 257
 258         batman_packet->tt_num_changes = tt_changes_fill_buffer(bat_priv,
 259                                 hard_iface->packet_buff + BAT_PACKET_LEN,
 260                                 hard_iface->packet_len - BAT_PACKET_LEN);
 261
 262 }
 263
 264 static void reset_packet_buffer(struct bat_priv *bat_priv,
 265         struct hard_iface *hard_iface)
 266 {
 267         struct batman_packet *batman_packet;
 268
 269         realloc_packet_buffer(hard_iface, BAT_PACKET_LEN);
 270
 271         batman_packet = (struct batman_packet *)hard_iface->packet_buff;
 272         batman_packet->tt_num_changes = 0;
 273 }
 274
 275 void schedule_own_packet(struct hard_iface *hard_iface)
 276 {
 277         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 278         struct hard_iface *primary_if;
 279         unsigned long send_time;
 280         struct batman_packet *batman_packet;
 281         int vis_server;
 282
 283         if ((hard_iface->if_status == IF_NOT_IN_USE) ||
 284             (hard_iface->if_status == IF_TO_BE_REMOVED))
 285                 return;
 286
 287         vis_server = atomic_read(&bat_priv->vis_mode);
 288         primary_if = primary_if_get_selected(bat_priv);
 289
 290         /**
 291          * the interface gets activated here to avoid race conditions between
 292          * the moment of activating the interface in
 293          * hardif_activate_interface() where the originator mac is set and
 294          * outdated packets (especially uninitialized mac addresses) in the
 295          * packet queue
 296          */
 297         if (hard_iface->if_status == IF_TO_BE_ACTIVATED)
 298                 hard_iface->if_status = IF_ACTIVE;
 299
 300         if (hard_iface == primary_if) {
 301                 /* if at least one change happened */
 302                 if (atomic_read(&bat_priv->tt_local_changes) > 0) {
 303                         prepare_packet_buffer(bat_priv, hard_iface);
 304                         /* Increment the TTVN only once per OGM interval */
 305                         atomic_inc(&bat_priv->ttvn);
 306                         bat_priv->tt_poss_change = false;
 307                 }
 308
 309                 /* if the changes have been sent enough times */
 310                 if (!atomic_dec_not_zero(&bat_priv->tt_ogm_append_cnt))
 311                         reset_packet_buffer(bat_priv, hard_iface);
 312         }
 313
 314         /**
 315          * NOTE: packet_buff might just have been re-allocated in
 316          * prepare_packet_buffer() or in reset_packet_buffer()
 317          */
 318         batman_packet = (struct batman_packet *)hard_iface->packet_buff;
 319
 320         /* change sequence number to network order */
 321         batman_packet->seqno =
 322                 htonl((uint32_t)atomic_read(&hard_iface->seqno));
 323
 324         batman_packet->ttvn = atomic_read(&bat_priv->ttvn);
 325         batman_packet->tt_crc = htons((uint16_t)atomic_read(&bat_priv->tt_crc));
 326
 327         if (vis_server == VIS_TYPE_SERVER_SYNC)
 328                 batman_packet->flags |= VIS_SERVER;
 329         else
 330                 batman_packet->flags &= ~VIS_SERVER;
 331
 332         if ((hard_iface == primary_if) &&
 333             (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
 334                 batman_packet->gw_flags =
 335                                 (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 336         else
 337                 batman_packet->gw_flags = NO_FLAGS;
 338
 339         atomic_inc(&hard_iface->seqno);
 340
 341         slide_own_bcast_window(hard_iface);
 342         send_time = own_send_time(bat_priv);
 343         add_bat_packet_to_list(bat_priv,
 344                                hard_iface->packet_buff,
 345                                hard_iface->packet_len,
 346                                hard_iface, 1, send_time);
 347
 348         if (primary_if)
 349                 hardif_free_ref(primary_if);
 350 }
 351
 352 void schedule_forward_packet(struct orig_node *orig_node,
 353                              const struct ethhdr *ethhdr,
 354                              struct batman_packet *batman_packet,
 355                              int directlink,
 356                              struct hard_iface *if_incoming)
 357 {
 358         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 359         struct neigh_node *router;
 360         uint8_t in_tq, in_ttl, tq_avg = 0;
 361         unsigned long send_time;
 362         uint8_t tt_num_changes;
 363
 364         if (batman_packet->ttl <= 1) {
 365                 bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
 366                 return;
 367         }
 368
 369         router = orig_node_get_router(orig_node);
 370
 371         in_tq = batman_packet->tq;
 372         in_ttl = batman_packet->ttl;
 373         tt_num_changes = batman_packet->tt_num_changes;
 374
 375         batman_packet->ttl--;
 376         memcpy(batman_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 377
 378         /* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
 379          * of our best tq value */
 380         if (router && router->tq_avg != 0) {
 381
 382                 /* rebroadcast ogm of best ranking neighbor as is */
 383                 if (!compare_eth(router->addr, ethhdr->h_source)) {
 384                         batman_packet->tq = router->tq_avg;
 385
 386                         if (router->last_ttl)
 387                                 batman_packet->ttl = router->last_ttl - 1;
 388                 }
 389
 390                 tq_avg = router->tq_avg;
 391         }
 392
 393         if (router)
 394                 neigh_node_free_ref(router);
 395
 396         /* apply hop penalty */
 397         batman_packet->tq = hop_penalty(batman_packet->tq, bat_priv);
 398
 399         bat_dbg(DBG_BATMAN, bat_priv,
 400                 "Forwarding packet: tq_orig: %i, tq_avg: %i, "
 401                 "tq_forw: %i, ttl_orig: %i, ttl_forw: %i\n",
 402                 in_tq, tq_avg, batman_packet->tq, in_ttl - 1,
 403                 batman_packet->ttl);
 404
 405         batman_packet->seqno = htonl(batman_packet->seqno);
 406         batman_packet->tt_crc = htons(batman_packet->tt_crc);
 407
 408         /* switch of primaries first hop flag when forwarding */
 409         batman_packet->flags &= ~PRIMARIES_FIRST_HOP;
 410         if (directlink)
 411                 batman_packet->flags |= DIRECTLINK;
 412         else
 413                 batman_packet->flags &= ~DIRECTLINK;
 414
 415         send_time = forward_send_time();
 416         add_bat_packet_to_list(bat_priv,
 417                                (unsigned char *)batman_packet,
 418                                sizeof(*batman_packet) + tt_len(tt_num_changes),
 419                                if_incoming, 0, send_time);
 420 }
 421
 422 static void forw_packet_free(struct forw_packet *forw_packet)
 423 {
 424         if (forw_packet->skb)
 425                 kfree_skb(forw_packet->skb);
 426         if (forw_packet->if_incoming)
 427                 hardif_free_ref(forw_packet->if_incoming);
 428         kfree(forw_packet);
 429 }
 430
 431 static void _add_bcast_packet_to_list(struct bat_priv *bat_priv,
 432                                       struct forw_packet *forw_packet,
 433                                       unsigned long send_time)
 434 {
 435         INIT_HLIST_NODE(&forw_packet->list);
 436
 437         /* add new packet to packet list */
 438         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 439         hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
 440         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 441
 442         /* start timer for this packet */
 443         INIT_DELAYED_WORK(&forw_packet->delayed_work,
 444                           send_outstanding_bcast_packet);
 445         queue_delayed_work(bat_event_workqueue, &forw_packet->delayed_work,
 446                            send_time);
 447 }
 448
 449 /* add a broadcast packet to the queue and setup timers. broadcast packets
 450  * are sent multiple times to increase probability for beeing received.
 451  *
 452  * This function returns NETDEV_TX_OK on success and NETDEV_TX_BUSY on
 453  * errors.
 454  *
 455  * The skb is not consumed, so the caller should make sure that the
 456  * skb is freed. */
 457 int add_bcast_packet_to_list(struct bat_priv *bat_priv,
 458                              const struct sk_buff *skb, unsigned long delay)
 459 {
 460         struct hard_iface *primary_if = NULL;
 461         struct forw_packet *forw_packet;
 462         struct bcast_packet *bcast_packet;
 463         struct sk_buff *newskb;
 464
 465         if (!atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
 466                 bat_dbg(DBG_BATMAN, bat_priv, "bcast packet queue full\n");
 467                 goto out;
 468         }
 469
 470         primary_if = primary_if_get_selected(bat_priv);
 471         if (!primary_if)
 472                 goto out_and_inc;
 473
 474         forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
 475
 476         if (!forw_packet)
 477                 goto out_and_inc;
 478
 479         newskb = skb_copy(skb, GFP_ATOMIC);
 480         if (!newskb)
 481                 goto packet_free;
 482
 483         /* as we have a copy now, it is safe to decrease the TTL */
 484         bcast_packet = (struct bcast_packet *)newskb->data;
 485         bcast_packet->ttl--;
 486
 487         skb_reset_mac_header(newskb);
 488
 489         forw_packet->skb = newskb;
 490         forw_packet->if_incoming = primary_if;
 491
 492         /* how often did we send the bcast packet ? */
 493         forw_packet->num_packets = 0;
 494
 495         _add_bcast_packet_to_list(bat_priv, forw_packet, delay);
 496         return NETDEV_TX_OK;
 497
 498 packet_free:
 499         kfree(forw_packet);
 500 out_and_inc:
 501         atomic_inc(&bat_priv->bcast_queue_left);
 502 out:
 503         if (primary_if)
 504                 hardif_free_ref(primary_if);
 505         return NETDEV_TX_BUSY;
 506 }
 507
 508 static void send_outstanding_bcast_packet(struct work_struct *work)
 509 {
 510         struct hard_iface *hard_iface;
 511         struct delayed_work *delayed_work =
 512                 container_of(work, struct delayed_work, work);
 513         struct forw_packet *forw_packet =
 514                 container_of(delayed_work, struct forw_packet, delayed_work);
 515         struct sk_buff *skb1;
 516         struct net_device *soft_iface = forw_packet->if_incoming->soft_iface;
 517         struct bat_priv *bat_priv = netdev_priv(soft_iface);
 518
 519         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 520         hlist_del(&forw_packet->list);
 521         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 522
 523         if (atomic_read(&bat_priv->mesh_state) == MESH_DEACTIVATING)
 524                 goto out;
 525
 526         /* rebroadcast packet */
 527         rcu_read_lock();
 528         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 529                 if (hard_iface->soft_iface != soft_iface)
 530                         continue;
 531
 532                 /* send a copy of the saved skb */
 533                 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
 534                 if (skb1)
 535                         send_skb_packet(skb1, hard_iface, broadcast_addr);
 536         }
 537         rcu_read_unlock();
 538
 539         forw_packet->num_packets++;
 540
 541         /* if we still have some more bcasts to send */
 542         if (forw_packet->num_packets < 3) {
 543                 _add_bcast_packet_to_list(bat_priv, forw_packet,
 544                                           ((5 * HZ) / 1000));
 545                 return;
 546         }
 547
 548 out:
 549         forw_packet_free(forw_packet);
 550         atomic_inc(&bat_priv->bcast_queue_left);
 551 }
 552
 553 void send_outstanding_bat_packet(struct work_struct *work)
 554 {
 555         struct delayed_work *delayed_work =
 556                 container_of(work, struct delayed_work, work);
 557         struct forw_packet *forw_packet =
 558                 container_of(delayed_work, struct forw_packet, delayed_work);
 559         struct bat_priv *bat_priv;
 560
 561         bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
 562         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 563         hlist_del(&forw_packet->list);
 564         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 565
 566         if (atomic_read(&bat_priv->mesh_state) == MESH_DEACTIVATING)
 567                 goto out;
 568
 569         send_packet(forw_packet);
 570
 571         /**
 572          * we have to have at least one packet in the queue
 573          * to determine the queues wake up time unless we are
 574          * shutting down
 575          */
 576         if (forw_packet->own)
 577                 schedule_own_packet(forw_packet->if_incoming);
 578
 579 out:
 580         /* don't count own packet */
 581         if (!forw_packet->own)
 582                 atomic_inc(&bat_priv->batman_queue_left);
 583
 584         forw_packet_free(forw_packet);
 585 }
 586
 587 void purge_outstanding_packets(struct bat_priv *bat_priv,
 588                                const struct hard_iface *hard_iface)
 589 {
 590         struct forw_packet *forw_packet;
 591         struct hlist_node *tmp_node, *safe_tmp_node;
 592         bool pending;
 593
 594         if (hard_iface)
 595                 bat_dbg(DBG_BATMAN, bat_priv,
 596                         "purge_outstanding_packets(): %s\n",
 597                         hard_iface->net_dev->name);
 598         else
 599                 bat_dbg(DBG_BATMAN, bat_priv,
 600                         "purge_outstanding_packets()\n");
 601
 602         /* free bcast list */
 603         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 604         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 605                                   &bat_priv->forw_bcast_list, list) {
 606
 607                 /**
 608                  * if purge_outstanding_packets() was called with an argmument
 609                  * we delete only packets belonging to the given interface
 610                  */
 611                 if ((hard_iface) &&
 612                     (forw_packet->if_incoming != hard_iface))
 613                         continue;
 614
 615                 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 616
 617                 /**
 618                  * send_outstanding_bcast_packet() will lock the list to
 619                  * delete the item from the list
 620                  */
 621                 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
 622                 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 623
 624                 if (pending) {
 625                         hlist_del(&forw_packet->list);
 626                         forw_packet_free(forw_packet);
 627                 }
 628         }
 629         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 630
 631         /* free batman packet list */
 632         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 633         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 634                                   &bat_priv->forw_bat_list, list) {
 635
 636                 /**
 637                  * if purge_outstanding_packets() was called with an argmument
 638                  * we delete only packets belonging to the given interface
 639                  */
 640                 if ((hard_iface) &&
 641                     (forw_packet->if_incoming != hard_iface))
 642                         continue;
 643
 644                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 645
 646                 /**
 647                  * send_outstanding_bat_packet() will lock the list to
 648                  * delete the item from the list
 649                  */
 650                 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
 651                 spin_lock_bh(&bat_priv->forw_bat_list_lock);
 652
 653                 if (pending) {
 654                         hlist_del(&forw_packet->list);
 655                         forw_packet_free(forw_packet);
 656                 }
 657         }
 658         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 659 }