xref: /linux/net/batman-adv/send.c (revision 10accd2e6890b57db8e717e9aee91b791f90fe14)
1 /* Copyright (C) 2007-2016  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 "send.h"
19 #include "main.h"
20 
21 #include <linux/atomic.h>
22 #include <linux/byteorder/generic.h>
23 #include <linux/errno.h>
24 #include <linux/etherdevice.h>
25 #include <linux/fs.h>
26 #include <linux/if.h>
27 #include <linux/if_ether.h>
28 #include <linux/jiffies.h>
29 #include <linux/kernel.h>
30 #include <linux/kref.h>
31 #include <linux/list.h>
32 #include <linux/netdevice.h>
33 #include <linux/printk.h>
34 #include <linux/rculist.h>
35 #include <linux/rcupdate.h>
36 #include <linux/skbuff.h>
37 #include <linux/slab.h>
38 #include <linux/spinlock.h>
39 #include <linux/stddef.h>
40 #include <linux/workqueue.h>
41 
42 #include "distributed-arp-table.h"
43 #include "fragmentation.h"
44 #include "gateway_client.h"
45 #include "hard-interface.h"
46 #include "log.h"
47 #include "network-coding.h"
48 #include "originator.h"
49 #include "routing.h"
50 #include "soft-interface.h"
51 #include "translation-table.h"
52 
53 static void batadv_send_outstanding_bcast_packet(struct work_struct *work);
54 
55 /**
56  * batadv_send_skb_packet - send an already prepared packet
57  * @skb: the packet to send
58  * @hard_iface: the interface to use to send the broadcast packet
59  * @dst_addr: the payload destination
60  *
61  * Send out an already prepared packet to the given neighbor or broadcast it
62  * using the specified interface. Either hard_iface or neigh_node must be not
63  * NULL.
64  * If neigh_node is NULL, then the packet is broadcasted using hard_iface,
65  * otherwise it is sent as unicast to the given neighbor.
66  *
67  * Return: NET_TX_DROP in case of error or the result of dev_queue_xmit(skb)
68  * otherwise
69  */
70 int batadv_send_skb_packet(struct sk_buff *skb,
71 			   struct batadv_hard_iface *hard_iface,
72 			   const u8 *dst_addr)
73 {
74 	struct batadv_priv *bat_priv;
75 	struct ethhdr *ethhdr;
76 	int ret;
77 
78 	bat_priv = netdev_priv(hard_iface->soft_iface);
79 
80 	if (hard_iface->if_status != BATADV_IF_ACTIVE)
81 		goto send_skb_err;
82 
83 	if (unlikely(!hard_iface->net_dev))
84 		goto send_skb_err;
85 
86 	if (!(hard_iface->net_dev->flags & IFF_UP)) {
87 		pr_warn("Interface %s is not up - can't send packet via that interface!\n",
88 			hard_iface->net_dev->name);
89 		goto send_skb_err;
90 	}
91 
92 	/* push to the ethernet header. */
93 	if (batadv_skb_head_push(skb, ETH_HLEN) < 0)
94 		goto send_skb_err;
95 
96 	skb_reset_mac_header(skb);
97 
98 	ethhdr = eth_hdr(skb);
99 	ether_addr_copy(ethhdr->h_source, hard_iface->net_dev->dev_addr);
100 	ether_addr_copy(ethhdr->h_dest, dst_addr);
101 	ethhdr->h_proto = htons(ETH_P_BATMAN);
102 
103 	skb_set_network_header(skb, ETH_HLEN);
104 	skb->protocol = htons(ETH_P_BATMAN);
105 
106 	skb->dev = hard_iface->net_dev;
107 
108 	/* Save a clone of the skb to use when decoding coded packets */
109 	batadv_nc_skb_store_for_decoding(bat_priv, skb);
110 
111 	/* dev_queue_xmit() returns a negative result on error.	 However on
112 	 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
113 	 * (which is > 0). This will not be treated as an error.
114 	 *
115 	 * a negative value cannot be returned because it could be interepreted
116 	 * as not consumed skb by callers of batadv_send_skb_to_orig.
117 	 */
118 	ret = dev_queue_xmit(skb);
119 	if (ret < 0)
120 		ret = NET_XMIT_DROP;
121 
122 	return ret;
123 send_skb_err:
124 	kfree_skb(skb);
125 	return NET_XMIT_DROP;
126 }
127 
128 int batadv_send_broadcast_skb(struct sk_buff *skb,
129 			      struct batadv_hard_iface *hard_iface)
130 {
131 	return batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
132 }
133 
134 int batadv_send_unicast_skb(struct sk_buff *skb,
135 			    struct batadv_neigh_node *neigh)
136 {
137 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
138 	struct batadv_hardif_neigh_node *hardif_neigh;
139 #endif
140 	int ret;
141 
142 	ret = batadv_send_skb_packet(skb, neigh->if_incoming, neigh->addr);
143 
144 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
145 	hardif_neigh = batadv_hardif_neigh_get(neigh->if_incoming, neigh->addr);
146 
147 	if ((hardif_neigh) && (ret != NET_XMIT_DROP))
148 		hardif_neigh->bat_v.last_unicast_tx = jiffies;
149 
150 	if (hardif_neigh)
151 		batadv_hardif_neigh_put(hardif_neigh);
152 #endif
153 
154 	return ret;
155 }
156 
157 /**
158  * batadv_send_skb_to_orig - Lookup next-hop and transmit skb.
159  * @skb: Packet to be transmitted.
160  * @orig_node: Final destination of the packet.
161  * @recv_if: Interface used when receiving the packet (can be NULL).
162  *
163  * Looks up the best next-hop towards the passed originator and passes the
164  * skb on for preparation of MAC header. If the packet originated from this
165  * host, NULL can be passed as recv_if and no interface alternating is
166  * attempted.
167  *
168  * Return: -1 on failure (and the skb is not consumed), -EINPROGRESS if the
169  * skb is buffered for later transmit or the NET_XMIT status returned by the
170  * lower routine if the packet has been passed down.
171  *
172  * If the returning value is not -1 the skb has been consumed.
173  */
174 int batadv_send_skb_to_orig(struct sk_buff *skb,
175 			    struct batadv_orig_node *orig_node,
176 			    struct batadv_hard_iface *recv_if)
177 {
178 	struct batadv_priv *bat_priv = orig_node->bat_priv;
179 	struct batadv_neigh_node *neigh_node;
180 	int ret = -1;
181 
182 	/* batadv_find_router() increases neigh_nodes refcount if found. */
183 	neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
184 	if (!neigh_node)
185 		goto out;
186 
187 	/* Check if the skb is too large to send in one piece and fragment
188 	 * it if needed.
189 	 */
190 	if (atomic_read(&bat_priv->fragmentation) &&
191 	    skb->len > neigh_node->if_incoming->net_dev->mtu) {
192 		/* Fragment and send packet. */
193 		ret = batadv_frag_send_packet(skb, orig_node, neigh_node);
194 
195 		goto out;
196 	}
197 
198 	/* try to network code the packet, if it is received on an interface
199 	 * (i.e. being forwarded). If the packet originates from this node or if
200 	 * network coding fails, then send the packet as usual.
201 	 */
202 	if (recv_if && batadv_nc_skb_forward(skb, neigh_node))
203 		ret = -EINPROGRESS;
204 	else
205 		ret = batadv_send_unicast_skb(skb, neigh_node);
206 
207 out:
208 	if (neigh_node)
209 		batadv_neigh_node_put(neigh_node);
210 
211 	return ret;
212 }
213 
214 /**
215  * batadv_send_skb_push_fill_unicast - extend the buffer and initialize the
216  *  common fields for unicast packets
217  * @skb: the skb carrying the unicast header to initialize
218  * @hdr_size: amount of bytes to push at the beginning of the skb
219  * @orig_node: the destination node
220  *
221  * Return: false if the buffer extension was not possible or true otherwise.
222  */
223 static bool
224 batadv_send_skb_push_fill_unicast(struct sk_buff *skb, int hdr_size,
225 				  struct batadv_orig_node *orig_node)
226 {
227 	struct batadv_unicast_packet *unicast_packet;
228 	u8 ttvn = (u8)atomic_read(&orig_node->last_ttvn);
229 
230 	if (batadv_skb_head_push(skb, hdr_size) < 0)
231 		return false;
232 
233 	unicast_packet = (struct batadv_unicast_packet *)skb->data;
234 	unicast_packet->version = BATADV_COMPAT_VERSION;
235 	/* batman packet type: unicast */
236 	unicast_packet->packet_type = BATADV_UNICAST;
237 	/* set unicast ttl */
238 	unicast_packet->ttl = BATADV_TTL;
239 	/* copy the destination for faster routing */
240 	ether_addr_copy(unicast_packet->dest, orig_node->orig);
241 	/* set the destination tt version number */
242 	unicast_packet->ttvn = ttvn;
243 
244 	return true;
245 }
246 
247 /**
248  * batadv_send_skb_prepare_unicast - encapsulate an skb with a unicast header
249  * @skb: the skb containing the payload to encapsulate
250  * @orig_node: the destination node
251  *
252  * Return: false if the payload could not be encapsulated or true otherwise.
253  */
254 static bool batadv_send_skb_prepare_unicast(struct sk_buff *skb,
255 					    struct batadv_orig_node *orig_node)
256 {
257 	size_t uni_size = sizeof(struct batadv_unicast_packet);
258 
259 	return batadv_send_skb_push_fill_unicast(skb, uni_size, orig_node);
260 }
261 
262 /**
263  * batadv_send_skb_prepare_unicast_4addr - encapsulate an skb with a
264  *  unicast 4addr header
265  * @bat_priv: the bat priv with all the soft interface information
266  * @skb: the skb containing the payload to encapsulate
267  * @orig: the destination node
268  * @packet_subtype: the unicast 4addr packet subtype to use
269  *
270  * Return: false if the payload could not be encapsulated or true otherwise.
271  */
272 bool batadv_send_skb_prepare_unicast_4addr(struct batadv_priv *bat_priv,
273 					   struct sk_buff *skb,
274 					   struct batadv_orig_node *orig,
275 					   int packet_subtype)
276 {
277 	struct batadv_hard_iface *primary_if;
278 	struct batadv_unicast_4addr_packet *uc_4addr_packet;
279 	bool ret = false;
280 
281 	primary_if = batadv_primary_if_get_selected(bat_priv);
282 	if (!primary_if)
283 		goto out;
284 
285 	/* Pull the header space and fill the unicast_packet substructure.
286 	 * We can do that because the first member of the uc_4addr_packet
287 	 * is of type struct unicast_packet
288 	 */
289 	if (!batadv_send_skb_push_fill_unicast(skb, sizeof(*uc_4addr_packet),
290 					       orig))
291 		goto out;
292 
293 	uc_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
294 	uc_4addr_packet->u.packet_type = BATADV_UNICAST_4ADDR;
295 	ether_addr_copy(uc_4addr_packet->src, primary_if->net_dev->dev_addr);
296 	uc_4addr_packet->subtype = packet_subtype;
297 	uc_4addr_packet->reserved = 0;
298 
299 	ret = true;
300 out:
301 	if (primary_if)
302 		batadv_hardif_put(primary_if);
303 	return ret;
304 }
305 
306 /**
307  * batadv_send_skb_unicast - encapsulate and send an skb via unicast
308  * @bat_priv: the bat priv with all the soft interface information
309  * @skb: payload to send
310  * @packet_type: the batman unicast packet type to use
311  * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
312  *  4addr packets)
313  * @orig_node: the originator to send the packet to
314  * @vid: the vid to be used to search the translation table
315  *
316  * Wrap the given skb into a batman-adv unicast or unicast-4addr header
317  * depending on whether BATADV_UNICAST or BATADV_UNICAST_4ADDR was supplied
318  * as packet_type. Then send this frame to the given orig_node and release a
319  * reference to this orig_node.
320  *
321  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
322  */
323 int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
324 			    struct sk_buff *skb, int packet_type,
325 			    int packet_subtype,
326 			    struct batadv_orig_node *orig_node,
327 			    unsigned short vid)
328 {
329 	struct batadv_unicast_packet *unicast_packet;
330 	struct ethhdr *ethhdr;
331 	int res, ret = NET_XMIT_DROP;
332 
333 	if (!orig_node)
334 		goto out;
335 
336 	switch (packet_type) {
337 	case BATADV_UNICAST:
338 		if (!batadv_send_skb_prepare_unicast(skb, orig_node))
339 			goto out;
340 		break;
341 	case BATADV_UNICAST_4ADDR:
342 		if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, skb,
343 							   orig_node,
344 							   packet_subtype))
345 			goto out;
346 		break;
347 	default:
348 		/* this function supports UNICAST and UNICAST_4ADDR only. It
349 		 * should never be invoked with any other packet type
350 		 */
351 		goto out;
352 	}
353 
354 	/* skb->data might have been reallocated by
355 	 * batadv_send_skb_prepare_unicast{,_4addr}()
356 	 */
357 	ethhdr = eth_hdr(skb);
358 	unicast_packet = (struct batadv_unicast_packet *)skb->data;
359 
360 	/* inform the destination node that we are still missing a correct route
361 	 * for this client. The destination will receive this packet and will
362 	 * try to reroute it because the ttvn contained in the header is less
363 	 * than the current one
364 	 */
365 	if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest, vid))
366 		unicast_packet->ttvn = unicast_packet->ttvn - 1;
367 
368 	res = batadv_send_skb_to_orig(skb, orig_node, NULL);
369 	if (res != -1)
370 		ret = NET_XMIT_SUCCESS;
371 
372 out:
373 	if (orig_node)
374 		batadv_orig_node_put(orig_node);
375 	if (ret == NET_XMIT_DROP)
376 		kfree_skb(skb);
377 	return ret;
378 }
379 
380 /**
381  * batadv_send_skb_via_tt_generic - send an skb via TT lookup
382  * @bat_priv: the bat priv with all the soft interface information
383  * @skb: payload to send
384  * @packet_type: the batman unicast packet type to use
385  * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
386  *  4addr packets)
387  * @dst_hint: can be used to override the destination contained in the skb
388  * @vid: the vid to be used to search the translation table
389  *
390  * Look up the recipient node for the destination address in the ethernet
391  * header via the translation table. Wrap the given skb into a batman-adv
392  * unicast or unicast-4addr header depending on whether BATADV_UNICAST or
393  * BATADV_UNICAST_4ADDR was supplied as packet_type. Then send this frame
394  * to the according destination node.
395  *
396  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
397  */
398 int batadv_send_skb_via_tt_generic(struct batadv_priv *bat_priv,
399 				   struct sk_buff *skb, int packet_type,
400 				   int packet_subtype, u8 *dst_hint,
401 				   unsigned short vid)
402 {
403 	struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
404 	struct batadv_orig_node *orig_node;
405 	u8 *src, *dst;
406 
407 	src = ethhdr->h_source;
408 	dst = ethhdr->h_dest;
409 
410 	/* if we got an hint! let's send the packet to this client (if any) */
411 	if (dst_hint) {
412 		src = NULL;
413 		dst = dst_hint;
414 	}
415 	orig_node = batadv_transtable_search(bat_priv, src, dst, vid);
416 
417 	return batadv_send_skb_unicast(bat_priv, skb, packet_type,
418 				       packet_subtype, orig_node, vid);
419 }
420 
421 /**
422  * batadv_send_skb_via_gw - send an skb via gateway lookup
423  * @bat_priv: the bat priv with all the soft interface information
424  * @skb: payload to send
425  * @vid: the vid to be used to search the translation table
426  *
427  * Look up the currently selected gateway. Wrap the given skb into a batman-adv
428  * unicast header and send this frame to this gateway node.
429  *
430  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
431  */
432 int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb,
433 			   unsigned short vid)
434 {
435 	struct batadv_orig_node *orig_node;
436 
437 	orig_node = batadv_gw_get_selected_orig(bat_priv);
438 	return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST_4ADDR,
439 				       BATADV_P_DATA, orig_node, vid);
440 }
441 
442 void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
443 {
444 	kfree_skb(forw_packet->skb);
445 	if (forw_packet->if_incoming)
446 		batadv_hardif_put(forw_packet->if_incoming);
447 	if (forw_packet->if_outgoing)
448 		batadv_hardif_put(forw_packet->if_outgoing);
449 	kfree(forw_packet);
450 }
451 
452 static void
453 _batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
454 				 struct batadv_forw_packet *forw_packet,
455 				 unsigned long send_time)
456 {
457 	/* add new packet to packet list */
458 	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
459 	hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
460 	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
461 
462 	/* start timer for this packet */
463 	queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work,
464 			   send_time);
465 }
466 
467 /**
468  * batadv_add_bcast_packet_to_list - queue broadcast packet for multiple sends
469  * @bat_priv: the bat priv with all the soft interface information
470  * @skb: broadcast packet to add
471  * @delay: number of jiffies to wait before sending
472  *
473  * add a broadcast packet to the queue and setup timers. broadcast packets
474  * are sent multiple times to increase probability for being received.
475  *
476  * The skb is not consumed, so the caller should make sure that the
477  * skb is freed.
478  *
479  * Return: NETDEV_TX_OK on success and NETDEV_TX_BUSY on errors.
480  */
481 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
482 				    const struct sk_buff *skb,
483 				    unsigned long delay)
484 {
485 	struct batadv_hard_iface *primary_if = NULL;
486 	struct batadv_forw_packet *forw_packet;
487 	struct batadv_bcast_packet *bcast_packet;
488 	struct sk_buff *newskb;
489 
490 	if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
491 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
492 			   "bcast packet queue full\n");
493 		goto out;
494 	}
495 
496 	primary_if = batadv_primary_if_get_selected(bat_priv);
497 	if (!primary_if)
498 		goto out_and_inc;
499 
500 	forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
501 
502 	if (!forw_packet)
503 		goto out_and_inc;
504 
505 	newskb = skb_copy(skb, GFP_ATOMIC);
506 	if (!newskb)
507 		goto packet_free;
508 
509 	/* as we have a copy now, it is safe to decrease the TTL */
510 	bcast_packet = (struct batadv_bcast_packet *)newskb->data;
511 	bcast_packet->ttl--;
512 
513 	skb_reset_mac_header(newskb);
514 
515 	forw_packet->skb = newskb;
516 	forw_packet->if_incoming = primary_if;
517 	forw_packet->if_outgoing = NULL;
518 
519 	/* how often did we send the bcast packet ? */
520 	forw_packet->num_packets = 0;
521 
522 	INIT_DELAYED_WORK(&forw_packet->delayed_work,
523 			  batadv_send_outstanding_bcast_packet);
524 
525 	_batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
526 	return NETDEV_TX_OK;
527 
528 packet_free:
529 	kfree(forw_packet);
530 out_and_inc:
531 	atomic_inc(&bat_priv->bcast_queue_left);
532 out:
533 	if (primary_if)
534 		batadv_hardif_put(primary_if);
535 	return NETDEV_TX_BUSY;
536 }
537 
538 static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
539 {
540 	struct batadv_hard_iface *hard_iface;
541 	struct delayed_work *delayed_work;
542 	struct batadv_forw_packet *forw_packet;
543 	struct sk_buff *skb1;
544 	struct net_device *soft_iface;
545 	struct batadv_priv *bat_priv;
546 
547 	delayed_work = to_delayed_work(work);
548 	forw_packet = container_of(delayed_work, struct batadv_forw_packet,
549 				   delayed_work);
550 	soft_iface = forw_packet->if_incoming->soft_iface;
551 	bat_priv = netdev_priv(soft_iface);
552 
553 	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
554 	hlist_del(&forw_packet->list);
555 	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
556 
557 	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
558 		goto out;
559 
560 	if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet))
561 		goto out;
562 
563 	/* rebroadcast packet */
564 	rcu_read_lock();
565 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
566 		if (hard_iface->soft_iface != soft_iface)
567 			continue;
568 
569 		if (forw_packet->num_packets >= hard_iface->num_bcasts)
570 			continue;
571 
572 		if (!kref_get_unless_zero(&hard_iface->refcount))
573 			continue;
574 
575 		/* send a copy of the saved skb */
576 		skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
577 		if (skb1)
578 			batadv_send_broadcast_skb(skb1, hard_iface);
579 
580 		batadv_hardif_put(hard_iface);
581 	}
582 	rcu_read_unlock();
583 
584 	forw_packet->num_packets++;
585 
586 	/* if we still have some more bcasts to send */
587 	if (forw_packet->num_packets < BATADV_NUM_BCASTS_MAX) {
588 		_batadv_add_bcast_packet_to_list(bat_priv, forw_packet,
589 						 msecs_to_jiffies(5));
590 		return;
591 	}
592 
593 out:
594 	batadv_forw_packet_free(forw_packet);
595 	atomic_inc(&bat_priv->bcast_queue_left);
596 }
597 
598 void
599 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
600 				 const struct batadv_hard_iface *hard_iface)
601 {
602 	struct batadv_forw_packet *forw_packet;
603 	struct hlist_node *safe_tmp_node;
604 	bool pending;
605 
606 	if (hard_iface)
607 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
608 			   "purge_outstanding_packets(): %s\n",
609 			   hard_iface->net_dev->name);
610 	else
611 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
612 			   "purge_outstanding_packets()\n");
613 
614 	/* free bcast list */
615 	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
616 	hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
617 				  &bat_priv->forw_bcast_list, list) {
618 		/* if purge_outstanding_packets() was called with an argument
619 		 * we delete only packets belonging to the given interface
620 		 */
621 		if ((hard_iface) &&
622 		    (forw_packet->if_incoming != hard_iface) &&
623 		    (forw_packet->if_outgoing != hard_iface))
624 			continue;
625 
626 		spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
627 
628 		/* batadv_send_outstanding_bcast_packet() will lock the list to
629 		 * delete the item from the list
630 		 */
631 		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
632 		spin_lock_bh(&bat_priv->forw_bcast_list_lock);
633 
634 		if (pending) {
635 			hlist_del(&forw_packet->list);
636 			if (!forw_packet->own)
637 				atomic_inc(&bat_priv->bcast_queue_left);
638 
639 			batadv_forw_packet_free(forw_packet);
640 		}
641 	}
642 	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
643 
644 	/* free batman packet list */
645 	spin_lock_bh(&bat_priv->forw_bat_list_lock);
646 	hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
647 				  &bat_priv->forw_bat_list, list) {
648 		/* if purge_outstanding_packets() was called with an argument
649 		 * we delete only packets belonging to the given interface
650 		 */
651 		if ((hard_iface) &&
652 		    (forw_packet->if_incoming != hard_iface) &&
653 		    (forw_packet->if_outgoing != hard_iface))
654 			continue;
655 
656 		spin_unlock_bh(&bat_priv->forw_bat_list_lock);
657 
658 		/* send_outstanding_bat_packet() will lock the list to
659 		 * delete the item from the list
660 		 */
661 		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
662 		spin_lock_bh(&bat_priv->forw_bat_list_lock);
663 
664 		if (pending) {
665 			hlist_del(&forw_packet->list);
666 			if (!forw_packet->own)
667 				atomic_inc(&bat_priv->batman_queue_left);
668 
669 			batadv_forw_packet_free(forw_packet);
670 		}
671 	}
672 	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
673 }
674