kernel/net/batman-adv/send.c

   1 /* Copyright (C) 2007-2014 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, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "main.h"
  19 #include "distributed-arp-table.h"
  20 #include "send.h"
  21 #include "routing.h"
  22 #include "translation-table.h"
  23 #include "soft-interface.h"
  24 #include "hard-interface.h"
  25 #include "gateway_common.h"
  26 #include "gateway_client.h"
  27 #include "originator.h"
  28 #include "network-coding.h"
  29 #include "fragmentation.h"
  30 #include "multicast.h"
  31
  32 static void batadv_send_outstanding_bcast_packet(struct work_struct *work);
  33
  34 /* send out an already prepared packet to the given address via the
  35  * specified batman interface
  36  */
  37 int batadv_send_skb_packet(struct sk_buff *skb,
  38                            struct batadv_hard_iface *hard_iface,
  39                            const uint8_t *dst_addr)
  40 {
  41         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
  42         struct ethhdr *ethhdr;
  43
  44         if (hard_iface->if_status != BATADV_IF_ACTIVE)
  45                 goto send_skb_err;
  46
  47         if (unlikely(!hard_iface->net_dev))
  48                 goto send_skb_err;
  49
  50         if (!(hard_iface->net_dev->flags & IFF_UP)) {
  51                 pr_warn("Interface %s is not up - can't send packet via that interface!\n",
  52                         hard_iface->net_dev->name);
  53                 goto send_skb_err;
  54         }
  55
  56         /* push to the ethernet header. */
  57         if (batadv_skb_head_push(skb, ETH_HLEN) < 0)
  58                 goto send_skb_err;
  59
  60         skb_reset_mac_header(skb);
  61
  62         ethhdr = eth_hdr(skb);
  63         ether_addr_copy(ethhdr->h_source, hard_iface->net_dev->dev_addr);
  64         ether_addr_copy(ethhdr->h_dest, dst_addr);
  65         ethhdr->h_proto = htons(ETH_P_BATMAN);
  66
  67         skb_set_network_header(skb, ETH_HLEN);
  68         skb->protocol = htons(ETH_P_BATMAN);
  69
  70         skb->dev = hard_iface->net_dev;
  71
  72         /* Save a clone of the skb to use when decoding coded packets */
  73         batadv_nc_skb_store_for_decoding(bat_priv, skb);
  74
  75         /* dev_queue_xmit() returns a negative result on error.  However on
  76          * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
  77          * (which is > 0). This will not be treated as an error.
  78          */
  79         return dev_queue_xmit(skb);
  80 send_skb_err:
  81         kfree_skb(skb);
  82         return NET_XMIT_DROP;
  83 }
  84
  85 /**
  86  * batadv_send_skb_to_orig - Lookup next-hop and transmit skb.
  87  * @skb: Packet to be transmitted.
  88  * @orig_node: Final destination of the packet.
  89  * @recv_if: Interface used when receiving the packet (can be NULL).
  90  *
  91  * Looks up the best next-hop towards the passed originator and passes the
  92  * skb on for preparation of MAC header. If the packet originated from this
  93  * host, NULL can be passed as recv_if and no interface alternating is
  94  * attempted.
  95  *
  96  * Returns NET_XMIT_SUCCESS on success, NET_XMIT_DROP on failure, or
  97  * NET_XMIT_POLICED if the skb is buffered for later transmit.
  98  */
  99 int batadv_send_skb_to_orig(struct sk_buff *skb,
 100                             struct batadv_orig_node *orig_node,
 101                             struct batadv_hard_iface *recv_if)
 102 {
 103         struct batadv_priv *bat_priv = orig_node->bat_priv;
 104         struct batadv_neigh_node *neigh_node;
 105         int ret = NET_XMIT_DROP;
 106
 107         /* batadv_find_router() increases neigh_nodes refcount if found. */
 108         neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
 109         if (!neigh_node)
 110                 goto out;
 111
 112         /* Check if the skb is too large to send in one piece and fragment
 113          * it if needed.
 114          */
 115         if (atomic_read(&bat_priv->fragmentation) &&
 116             skb->len > neigh_node->if_incoming->net_dev->mtu) {
 117                 /* Fragment and send packet. */
 118                 if (batadv_frag_send_packet(skb, orig_node, neigh_node))
 119                         ret = NET_XMIT_SUCCESS;
 120
 121                 goto out;
 122         }
 123
 124         /* try to network code the packet, if it is received on an interface
 125          * (i.e. being forwarded). If the packet originates from this node or if
 126          * network coding fails, then send the packet as usual.
 127          */
 128         if (recv_if && batadv_nc_skb_forward(skb, neigh_node)) {
 129                 ret = NET_XMIT_POLICED;
 130         } else {
 131                 batadv_send_skb_packet(skb, neigh_node->if_incoming,
 132                                        neigh_node->addr);
 133                 ret = NET_XMIT_SUCCESS;
 134         }
 135
 136 out:
 137         if (neigh_node)
 138                 batadv_neigh_node_free_ref(neigh_node);
 139
 140         return ret;
 141 }
 142
 143 /**
 144  * batadv_send_skb_push_fill_unicast - extend the buffer and initialize the
 145  *  common fields for unicast packets
 146  * @skb: the skb carrying the unicast header to initialize
 147  * @hdr_size: amount of bytes to push at the beginning of the skb
 148  * @orig_node: the destination node
 149  *
 150  * Returns false if the buffer extension was not possible or true otherwise.
 151  */
 152 static bool
 153 batadv_send_skb_push_fill_unicast(struct sk_buff *skb, int hdr_size,
 154                                   struct batadv_orig_node *orig_node)
 155 {
 156         struct batadv_unicast_packet *unicast_packet;
 157         uint8_t ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
 158
 159         if (batadv_skb_head_push(skb, hdr_size) < 0)
 160                 return false;
 161
 162         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 163         unicast_packet->version = BATADV_COMPAT_VERSION;
 164         /* batman packet type: unicast */
 165         unicast_packet->packet_type = BATADV_UNICAST;
 166         /* set unicast ttl */
 167         unicast_packet->ttl = BATADV_TTL;
 168         /* copy the destination for faster routing */
 169         ether_addr_copy(unicast_packet->dest, orig_node->orig);
 170         /* set the destination tt version number */
 171         unicast_packet->ttvn = ttvn;
 172
 173         return true;
 174 }
 175
 176 /**
 177  * batadv_send_skb_prepare_unicast - encapsulate an skb with a unicast header
 178  * @skb: the skb containing the payload to encapsulate
 179  * @orig_node: the destination node
 180  *
 181  * Returns false if the payload could not be encapsulated or true otherwise.
 182  */
 183 static bool batadv_send_skb_prepare_unicast(struct sk_buff *skb,
 184                                             struct batadv_orig_node *orig_node)
 185 {
 186         size_t uni_size = sizeof(struct batadv_unicast_packet);
 187
 188         return batadv_send_skb_push_fill_unicast(skb, uni_size, orig_node);
 189 }
 190
 191 /**
 192  * batadv_send_skb_prepare_unicast_4addr - encapsulate an skb with a
 193  *  unicast 4addr header
 194  * @bat_priv: the bat priv with all the soft interface information
 195  * @skb: the skb containing the payload to encapsulate
 196  * @orig_node: the destination node
 197  * @packet_subtype: the unicast 4addr packet subtype to use
 198  *
 199  * Returns false if the payload could not be encapsulated or true otherwise.
 200  */
 201 bool batadv_send_skb_prepare_unicast_4addr(struct batadv_priv *bat_priv,
 202                                            struct sk_buff *skb,
 203                                            struct batadv_orig_node *orig,
 204                                            int packet_subtype)
 205 {
 206         struct batadv_hard_iface *primary_if;
 207         struct batadv_unicast_4addr_packet *uc_4addr_packet;
 208         bool ret = false;
 209
 210         primary_if = batadv_primary_if_get_selected(bat_priv);
 211         if (!primary_if)
 212                 goto out;
 213
 214         /* Pull the header space and fill the unicast_packet substructure.
 215          * We can do that because the first member of the uc_4addr_packet
 216          * is of type struct unicast_packet
 217          */
 218         if (!batadv_send_skb_push_fill_unicast(skb, sizeof(*uc_4addr_packet),
 219                                                orig))
 220                 goto out;
 221
 222         uc_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
 223         uc_4addr_packet->u.packet_type = BATADV_UNICAST_4ADDR;
 224         ether_addr_copy(uc_4addr_packet->src, primary_if->net_dev->dev_addr);
 225         uc_4addr_packet->subtype = packet_subtype;
 226         uc_4addr_packet->reserved = 0;
 227
 228         ret = true;
 229 out:
 230         if (primary_if)
 231                 batadv_hardif_free_ref(primary_if);
 232         return ret;
 233 }
 234
 235 /**
 236  * batadv_send_skb_unicast - encapsulate and send an skb via unicast
 237  * @bat_priv: the bat priv with all the soft interface information
 238  * @skb: payload to send
 239  * @packet_type: the batman unicast packet type to use
 240  * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
 241  *  4addr packets)
 242  * @orig_node: the originator to send the packet to
 243  * @vid: the vid to be used to search the translation table
 244  *
 245  * Wrap the given skb into a batman-adv unicast or unicast-4addr header
 246  * depending on whether BATADV_UNICAST or BATADV_UNICAST_4ADDR was supplied
 247  * as packet_type. Then send this frame to the given orig_node and release a
 248  * reference to this orig_node.
 249  *
 250  * Returns NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
 251  */
 252 int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
 253                             struct sk_buff *skb, int packet_type,
 254                             int packet_subtype,
 255                             struct batadv_orig_node *orig_node,
 256                             unsigned short vid)
 257 {
 258         struct ethhdr *ethhdr;
 259         struct batadv_unicast_packet *unicast_packet;
 260         int ret = NET_XMIT_DROP;
 261
 262         if (!orig_node)
 263                 goto out;
 264
 265         switch (packet_type) {
 266         case BATADV_UNICAST:
 267                 if (!batadv_send_skb_prepare_unicast(skb, orig_node))
 268                         goto out;
 269                 break;
 270         case BATADV_UNICAST_4ADDR:
 271                 if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, skb,
 272                                                            orig_node,
 273                                                            packet_subtype))
 274                         goto out;
 275                 break;
 276         default:
 277                 /* this function supports UNICAST and UNICAST_4ADDR only. It
 278                  * should never be invoked with any other packet type
 279                  */
 280                 goto out;
 281         }
 282
 283         /* skb->data might have been reallocated by
 284          * batadv_send_skb_prepare_unicast{,_4addr}()
 285          */
 286         ethhdr = eth_hdr(skb);
 287         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 288
 289         /* inform the destination node that we are still missing a correct route
 290          * for this client. The destination will receive this packet and will
 291          * try to reroute it because the ttvn contained in the header is less
 292          * than the current one
 293          */
 294         if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest, vid))
 295                 unicast_packet->ttvn = unicast_packet->ttvn - 1;
 296
 297         if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
 298                 ret = NET_XMIT_SUCCESS;
 299
 300 out:
 301         if (orig_node)
 302                 batadv_orig_node_free_ref(orig_node);
 303         if (ret == NET_XMIT_DROP)
 304                 kfree_skb(skb);
 305         return ret;
 306 }
 307
 308 /**
 309  * batadv_send_skb_via_tt_generic - send an skb via TT lookup
 310  * @bat_priv: the bat priv with all the soft interface information
 311  * @skb: payload to send
 312  * @packet_type: the batman unicast packet type to use
 313  * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
 314  *  4addr packets)
 315  * @dst_hint: can be used to override the destination contained in the skb
 316  * @vid: the vid to be used to search the translation table
 317  *
 318  * Look up the recipient node for the destination address in the ethernet
 319  * header via the translation table. Wrap the given skb into a batman-adv
 320  * unicast or unicast-4addr header depending on whether BATADV_UNICAST or
 321  * BATADV_UNICAST_4ADDR was supplied as packet_type. Then send this frame
 322  * to the according destination node.
 323  *
 324  * Returns NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
 325  */
 326 int batadv_send_skb_via_tt_generic(struct batadv_priv *bat_priv,
 327                                    struct sk_buff *skb, int packet_type,
 328                                    int packet_subtype, uint8_t *dst_hint,
 329                                    unsigned short vid)
 330 {
 331         struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
 332         struct batadv_orig_node *orig_node;
 333         uint8_t *src, *dst;
 334
 335         src = ethhdr->h_source;
 336         dst = ethhdr->h_dest;
 337
 338         /* if we got an hint! let's send the packet to this client (if any) */
 339         if (dst_hint) {
 340                 src = NULL;
 341                 dst = dst_hint;
 342         }
 343         orig_node = batadv_transtable_search(bat_priv, src, dst, vid);
 344
 345         return batadv_send_skb_unicast(bat_priv, skb, packet_type,
 346                                        packet_subtype, orig_node, vid);
 347 }
 348
 349 /**
 350  * batadv_send_skb_via_gw - send an skb via gateway lookup
 351  * @bat_priv: the bat priv with all the soft interface information
 352  * @skb: payload to send
 353  * @vid: the vid to be used to search the translation table
 354  *
 355  * Look up the currently selected gateway. Wrap the given skb into a batman-adv
 356  * unicast header and send this frame to this gateway node.
 357  *
 358  * Returns NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
 359  */
 360 int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb,
 361                            unsigned short vid)
 362 {
 363         struct batadv_orig_node *orig_node;
 364
 365         orig_node = batadv_gw_get_selected_orig(bat_priv);
 366         return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST, 0,
 367                                        orig_node, vid);
 368 }
 369
 370 void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface)
 371 {
 372         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 373
 374         if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) ||
 375             (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
 376                 return;
 377
 378         /* the interface gets activated here to avoid race conditions between
 379          * the moment of activating the interface in
 380          * hardif_activate_interface() where the originator mac is set and
 381          * outdated packets (especially uninitialized mac addresses) in the
 382          * packet queue
 383          */
 384         if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
 385                 hard_iface->if_status = BATADV_IF_ACTIVE;
 386
 387         bat_priv->bat_algo_ops->bat_ogm_schedule(hard_iface);
 388 }
 389
 390 static void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
 391 {
 392         if (forw_packet->skb)
 393                 kfree_skb(forw_packet->skb);
 394         if (forw_packet->if_incoming)
 395                 batadv_hardif_free_ref(forw_packet->if_incoming);
 396         if (forw_packet->if_outgoing)
 397                 batadv_hardif_free_ref(forw_packet->if_outgoing);
 398         kfree(forw_packet);
 399 }
 400
 401 static void
 402 _batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 403                                  struct batadv_forw_packet *forw_packet,
 404                                  unsigned long send_time)
 405 {
 406         /* add new packet to packet list */
 407         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 408         hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
 409         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 410
 411         /* start timer for this packet */
 412         queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work,
 413                            send_time);
 414 }
 415
 416 /* add a broadcast packet to the queue and setup timers. broadcast packets
 417  * are sent multiple times to increase probability for being received.
 418  *
 419  * This function returns NETDEV_TX_OK on success and NETDEV_TX_BUSY on
 420  * errors.
 421  *
 422  * The skb is not consumed, so the caller should make sure that the
 423  * skb is freed.
 424  */
 425 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 426                                     const struct sk_buff *skb,
 427                                     unsigned long delay)
 428 {
 429         struct batadv_hard_iface *primary_if = NULL;
 430         struct batadv_forw_packet *forw_packet;
 431         struct batadv_bcast_packet *bcast_packet;
 432         struct sk_buff *newskb;
 433
 434         if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
 435                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 436                            "bcast packet queue full\n");
 437                 goto out;
 438         }
 439
 440         primary_if = batadv_primary_if_get_selected(bat_priv);
 441         if (!primary_if)
 442                 goto out_and_inc;
 443
 444         forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
 445
 446         if (!forw_packet)
 447                 goto out_and_inc;
 448
 449         newskb = skb_copy(skb, GFP_ATOMIC);
 450         if (!newskb)
 451                 goto packet_free;
 452
 453         /* as we have a copy now, it is safe to decrease the TTL */
 454         bcast_packet = (struct batadv_bcast_packet *)newskb->data;
 455         bcast_packet->ttl--;
 456
 457         skb_reset_mac_header(newskb);
 458
 459         forw_packet->skb = newskb;
 460         forw_packet->if_incoming = primary_if;
 461         forw_packet->if_outgoing = NULL;
 462
 463         /* how often did we send the bcast packet ? */
 464         forw_packet->num_packets = 0;
 465
 466         INIT_DELAYED_WORK(&forw_packet->delayed_work,
 467                           batadv_send_outstanding_bcast_packet);
 468
 469         _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
 470         return NETDEV_TX_OK;
 471
 472 packet_free:
 473         kfree(forw_packet);
 474 out_and_inc:
 475         atomic_inc(&bat_priv->bcast_queue_left);
 476 out:
 477         if (primary_if)
 478                 batadv_hardif_free_ref(primary_if);
 479         return NETDEV_TX_BUSY;
 480 }
 481
 482 static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
 483 {
 484         struct batadv_hard_iface *hard_iface;
 485         struct delayed_work *delayed_work;
 486         struct batadv_forw_packet *forw_packet;
 487         struct sk_buff *skb1;
 488         struct net_device *soft_iface;
 489         struct batadv_priv *bat_priv;
 490
 491         delayed_work = container_of(work, struct delayed_work, work);
 492         forw_packet = container_of(delayed_work, struct batadv_forw_packet,
 493                                    delayed_work);
 494         soft_iface = forw_packet->if_incoming->soft_iface;
 495         bat_priv = netdev_priv(soft_iface);
 496
 497         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 498         hlist_del(&forw_packet->list);
 499         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 500
 501         if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
 502                 goto out;
 503
 504         if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet))
 505                 goto out;
 506
 507         /* rebroadcast packet */
 508         rcu_read_lock();
 509         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 510                 if (hard_iface->soft_iface != soft_iface)
 511                         continue;
 512
 513                 if (forw_packet->num_packets >= hard_iface->num_bcasts)
 514                         continue;
 515
 516                 /* send a copy of the saved skb */
 517                 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
 518                 if (skb1)
 519                         batadv_send_skb_packet(skb1, hard_iface,
 520                                                batadv_broadcast_addr);
 521         }
 522         rcu_read_unlock();
 523
 524         forw_packet->num_packets++;
 525
 526         /* if we still have some more bcasts to send */
 527         if (forw_packet->num_packets < BATADV_NUM_BCASTS_MAX) {
 528                 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet,
 529                                                  msecs_to_jiffies(5));
 530                 return;
 531         }
 532
 533 out:
 534         batadv_forw_packet_free(forw_packet);
 535         atomic_inc(&bat_priv->bcast_queue_left);
 536 }
 537
 538 void batadv_send_outstanding_bat_ogm_packet(struct work_struct *work)
 539 {
 540         struct delayed_work *delayed_work;
 541         struct batadv_forw_packet *forw_packet;
 542         struct batadv_priv *bat_priv;
 543
 544         delayed_work = container_of(work, struct delayed_work, work);
 545         forw_packet = container_of(delayed_work, struct batadv_forw_packet,
 546                                    delayed_work);
 547         bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
 548         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 549         hlist_del(&forw_packet->list);
 550         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 551
 552         if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
 553                 goto out;
 554
 555         bat_priv->bat_algo_ops->bat_ogm_emit(forw_packet);
 556
 557         /* we have to have at least one packet in the queue to determine the
 558          * queues wake up time unless we are shutting down.
 559          *
 560          * only re-schedule if this is the "original" copy, e.g. the OGM of the
 561          * primary interface should only be rescheduled once per period, but
 562          * this function will be called for the forw_packet instances of the
 563          * other secondary interfaces as well.
 564          */
 565         if (forw_packet->own &&
 566             forw_packet->if_incoming == forw_packet->if_outgoing)
 567                 batadv_schedule_bat_ogm(forw_packet->if_incoming);
 568
 569 out:
 570         /* don't count own packet */
 571         if (!forw_packet->own)
 572                 atomic_inc(&bat_priv->batman_queue_left);
 573
 574         batadv_forw_packet_free(forw_packet);
 575 }
 576
 577 void
 578 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 579                                  const struct batadv_hard_iface *hard_iface)
 580 {
 581         struct batadv_forw_packet *forw_packet;
 582         struct hlist_node *safe_tmp_node;
 583         bool pending;
 584
 585         if (hard_iface)
 586                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 587                            "purge_outstanding_packets(): %s\n",
 588                            hard_iface->net_dev->name);
 589         else
 590                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 591                            "purge_outstanding_packets()\n");
 592
 593         /* free bcast list */
 594         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 595         hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
 596                                   &bat_priv->forw_bcast_list, list) {
 597                 /* if purge_outstanding_packets() was called with an argument
 598                  * we delete only packets belonging to the given interface
 599                  */
 600                 if ((hard_iface) &&
 601                     (forw_packet->if_incoming != hard_iface))
 602                         continue;
 603
 604                 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 605
 606                 /* batadv_send_outstanding_bcast_packet() will lock the list to
 607                  * delete the item from the list
 608                  */
 609                 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
 610                 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 611
 612                 if (pending) {
 613                         hlist_del(&forw_packet->list);
 614                         batadv_forw_packet_free(forw_packet);
 615                 }
 616         }
 617         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 618
 619         /* free batman packet list */
 620         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 621         hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
 622                                   &bat_priv->forw_bat_list, list) {
 623                 /* if purge_outstanding_packets() was called with an argument
 624                  * we delete only packets belonging to the given interface
 625                  */
 626                 if ((hard_iface) &&
 627                     (forw_packet->if_incoming != hard_iface) &&
 628                     (forw_packet->if_outgoing != hard_iface))
 629                         continue;
 630
 631                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 632
 633                 /* send_outstanding_bat_packet() will lock the list to
 634                  * delete the item from the list
 635                  */
 636                 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
 637                 spin_lock_bh(&bat_priv->forw_bat_list_lock);
 638
 639                 if (pending) {
 640                         hlist_del(&forw_packet->list);
 641                         batadv_forw_packet_free(forw_packet);
 642                 }
 643         }
 644         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 645 }