batman-adv: limit local translation table max size
[firefly-linux-kernel-4.4.55.git] / net / batman-adv / hard-interface.c
1 /* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
2  *
3  * Marek Lindner, Simon Wunderlich
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of version 2 of the GNU General Public
7  * License as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA
18  */
19
20 #include "main.h"
21 #include "distributed-arp-table.h"
22 #include "hard-interface.h"
23 #include "soft-interface.h"
24 #include "send.h"
25 #include "translation-table.h"
26 #include "routing.h"
27 #include "sysfs.h"
28 #include "originator.h"
29 #include "hash.h"
30 #include "bridge_loop_avoidance.h"
31
32 #include <linux/if_arp.h>
33 #include <linux/if_ether.h>
34
35 void batadv_hardif_free_rcu(struct rcu_head *rcu)
36 {
37         struct batadv_hard_iface *hard_iface;
38
39         hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
40         dev_put(hard_iface->net_dev);
41         kfree(hard_iface);
42 }
43
44 struct batadv_hard_iface *
45 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
46 {
47         struct batadv_hard_iface *hard_iface;
48
49         rcu_read_lock();
50         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
51                 if (hard_iface->net_dev == net_dev &&
52                     atomic_inc_not_zero(&hard_iface->refcount))
53                         goto out;
54         }
55
56         hard_iface = NULL;
57
58 out:
59         rcu_read_unlock();
60         return hard_iface;
61 }
62
63 /**
64  * batadv_is_on_batman_iface - check if a device is a batman iface descendant
65  * @net_dev: the device to check
66  *
67  * If the user creates any virtual device on top of a batman-adv interface, it
68  * is important to prevent this new interface to be used to create a new mesh
69  * network (this behaviour would lead to a batman-over-batman configuration).
70  * This function recursively checks all the fathers of the device passed as
71  * argument looking for a batman-adv soft interface.
72  *
73  * Returns true if the device is descendant of a batman-adv mesh interface (or
74  * if it is a batman-adv interface itself), false otherwise
75  */
76 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
77 {
78         struct net_device *parent_dev;
79         bool ret;
80
81         /* check if this is a batman-adv mesh interface */
82         if (batadv_softif_is_valid(net_dev))
83                 return true;
84
85         /* no more parents..stop recursion */
86         if (net_dev->iflink == net_dev->ifindex)
87                 return false;
88
89         /* recurse over the parent device */
90         parent_dev = dev_get_by_index(&init_net, net_dev->iflink);
91         /* if we got a NULL parent_dev there is something broken.. */
92         if (WARN(!parent_dev, "Cannot find parent device"))
93                 return false;
94
95         ret = batadv_is_on_batman_iface(parent_dev);
96
97         if (parent_dev)
98                 dev_put(parent_dev);
99         return ret;
100 }
101
102 static int batadv_is_valid_iface(const struct net_device *net_dev)
103 {
104         if (net_dev->flags & IFF_LOOPBACK)
105                 return 0;
106
107         if (net_dev->type != ARPHRD_ETHER)
108                 return 0;
109
110         if (net_dev->addr_len != ETH_ALEN)
111                 return 0;
112
113         /* no batman over batman */
114         if (batadv_is_on_batman_iface(net_dev))
115                 return 0;
116
117         return 1;
118 }
119
120 /**
121  * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
122  *  interface
123  * @net_device: the device to check
124  *
125  * Returns true if the net device is a 802.11 wireless device, false otherwise.
126  */
127 static bool batadv_is_wifi_netdev(struct net_device *net_device)
128 {
129 #ifdef CONFIG_WIRELESS_EXT
130         /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
131          * check for wireless_handlers != NULL
132          */
133         if (net_device->wireless_handlers)
134                 return true;
135 #endif
136
137         /* cfg80211 drivers have to set ieee80211_ptr */
138         if (net_device->ieee80211_ptr)
139                 return true;
140
141         return false;
142 }
143
144 /**
145  * batadv_is_wifi_iface - check if the given interface represented by ifindex
146  *  is a wifi interface
147  * @ifindex: interface index to check
148  *
149  * Returns true if the interface represented by ifindex is a 802.11 wireless
150  * device, false otherwise.
151  */
152 bool batadv_is_wifi_iface(int ifindex)
153 {
154         struct net_device *net_device = NULL;
155         bool ret = false;
156
157         if (ifindex == BATADV_NULL_IFINDEX)
158                 goto out;
159
160         net_device = dev_get_by_index(&init_net, ifindex);
161         if (!net_device)
162                 goto out;
163
164         ret = batadv_is_wifi_netdev(net_device);
165
166 out:
167         if (net_device)
168                 dev_put(net_device);
169         return ret;
170 }
171
172 static struct batadv_hard_iface *
173 batadv_hardif_get_active(const struct net_device *soft_iface)
174 {
175         struct batadv_hard_iface *hard_iface;
176
177         rcu_read_lock();
178         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
179                 if (hard_iface->soft_iface != soft_iface)
180                         continue;
181
182                 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
183                     atomic_inc_not_zero(&hard_iface->refcount))
184                         goto out;
185         }
186
187         hard_iface = NULL;
188
189 out:
190         rcu_read_unlock();
191         return hard_iface;
192 }
193
194 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
195                                           struct batadv_hard_iface *oldif)
196 {
197         struct batadv_hard_iface *primary_if;
198
199         primary_if = batadv_primary_if_get_selected(bat_priv);
200         if (!primary_if)
201                 goto out;
202
203         batadv_dat_init_own_addr(bat_priv, primary_if);
204         batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
205 out:
206         if (primary_if)
207                 batadv_hardif_free_ref(primary_if);
208 }
209
210 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
211                                      struct batadv_hard_iface *new_hard_iface)
212 {
213         struct batadv_hard_iface *curr_hard_iface;
214
215         ASSERT_RTNL();
216
217         if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
218                 new_hard_iface = NULL;
219
220         curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
221         rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
222
223         if (!new_hard_iface)
224                 goto out;
225
226         bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
227         batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
228
229 out:
230         if (curr_hard_iface)
231                 batadv_hardif_free_ref(curr_hard_iface);
232 }
233
234 static bool
235 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
236 {
237         if (hard_iface->net_dev->flags & IFF_UP)
238                 return true;
239
240         return false;
241 }
242
243 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
244 {
245         const struct batadv_hard_iface *hard_iface;
246
247         rcu_read_lock();
248         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
249                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
250                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
251                         continue;
252
253                 if (hard_iface->net_dev == net_dev)
254                         continue;
255
256                 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
257                                         net_dev->dev_addr))
258                         continue;
259
260                 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
261                         net_dev->dev_addr, hard_iface->net_dev->name);
262                 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
263         }
264         rcu_read_unlock();
265 }
266
267 int batadv_hardif_min_mtu(struct net_device *soft_iface)
268 {
269         struct batadv_priv *bat_priv = netdev_priv(soft_iface);
270         const struct batadv_hard_iface *hard_iface;
271         int min_mtu = ETH_DATA_LEN;
272
273         rcu_read_lock();
274         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
275                 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
276                     (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
277                         continue;
278
279                 if (hard_iface->soft_iface != soft_iface)
280                         continue;
281
282                 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
283         }
284         rcu_read_unlock();
285
286         atomic_set(&bat_priv->packet_size_max, min_mtu);
287
288         if (atomic_read(&bat_priv->fragmentation) == 0)
289                 goto out;
290
291         /* with fragmentation enabled the maximum size of internally generated
292          * packets such as translation table exchanges or tvlv containers, etc
293          * has to be calculated
294          */
295         min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
296         min_mtu -= sizeof(struct batadv_frag_packet);
297         min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
298         atomic_set(&bat_priv->packet_size_max, min_mtu);
299
300         /* with fragmentation enabled we can fragment external packets easily */
301         min_mtu = min_t(int, min_mtu, ETH_DATA_LEN);
302
303 out:
304         return min_mtu - batadv_max_header_len();
305 }
306
307 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
308 void batadv_update_min_mtu(struct net_device *soft_iface)
309 {
310         soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
311
312         /* Check if the local translate table should be cleaned up to match a
313          * new (and smaller) MTU.
314          */
315         batadv_tt_local_resize_to_mtu(soft_iface);
316 }
317
318 static void
319 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
320 {
321         struct batadv_priv *bat_priv;
322         struct batadv_hard_iface *primary_if = NULL;
323
324         if (hard_iface->if_status != BATADV_IF_INACTIVE)
325                 goto out;
326
327         bat_priv = netdev_priv(hard_iface->soft_iface);
328
329         bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
330         hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
331
332         /* the first active interface becomes our primary interface or
333          * the next active interface after the old primary interface was removed
334          */
335         primary_if = batadv_primary_if_get_selected(bat_priv);
336         if (!primary_if)
337                 batadv_primary_if_select(bat_priv, hard_iface);
338
339         batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
340                     hard_iface->net_dev->name);
341
342         batadv_update_min_mtu(hard_iface->soft_iface);
343
344 out:
345         if (primary_if)
346                 batadv_hardif_free_ref(primary_if);
347 }
348
349 static void
350 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
351 {
352         if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
353             (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
354                 return;
355
356         hard_iface->if_status = BATADV_IF_INACTIVE;
357
358         batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
359                     hard_iface->net_dev->name);
360
361         batadv_update_min_mtu(hard_iface->soft_iface);
362 }
363
364 /**
365  * batadv_master_del_slave - remove hard_iface from the current master interface
366  * @slave: the interface enslaved in another master
367  * @master: the master from which slave has to be removed
368  *
369  * Invoke ndo_del_slave on master passing slave as argument. In this way slave
370  * is free'd and master can correctly change its internal state.
371  * Return 0 on success, a negative value representing the error otherwise
372  */
373 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
374                                    struct net_device *master)
375 {
376         int ret;
377
378         if (!master)
379                 return 0;
380
381         ret = -EBUSY;
382         if (master->netdev_ops->ndo_del_slave)
383                 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
384
385         return ret;
386 }
387
388 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
389                                    const char *iface_name)
390 {
391         struct batadv_priv *bat_priv;
392         struct net_device *soft_iface, *master;
393         __be16 ethertype = htons(ETH_P_BATMAN);
394         int max_header_len = batadv_max_header_len();
395         int ret;
396
397         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
398                 goto out;
399
400         if (!atomic_inc_not_zero(&hard_iface->refcount))
401                 goto out;
402
403         soft_iface = dev_get_by_name(&init_net, iface_name);
404
405         if (!soft_iface) {
406                 soft_iface = batadv_softif_create(iface_name);
407
408                 if (!soft_iface) {
409                         ret = -ENOMEM;
410                         goto err;
411                 }
412
413                 /* dev_get_by_name() increases the reference counter for us */
414                 dev_hold(soft_iface);
415         }
416
417         if (!batadv_softif_is_valid(soft_iface)) {
418                 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
419                        soft_iface->name);
420                 ret = -EINVAL;
421                 goto err_dev;
422         }
423
424         /* check if the interface is enslaved in another virtual one and
425          * in that case unlink it first
426          */
427         master = netdev_master_upper_dev_get(hard_iface->net_dev);
428         ret = batadv_master_del_slave(hard_iface, master);
429         if (ret)
430                 goto err_dev;
431
432         hard_iface->soft_iface = soft_iface;
433         bat_priv = netdev_priv(hard_iface->soft_iface);
434
435         ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
436         if (ret)
437                 goto err_dev;
438
439         ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
440         if (ret < 0)
441                 goto err_upper;
442
443         hard_iface->if_num = bat_priv->num_ifaces;
444         bat_priv->num_ifaces++;
445         hard_iface->if_status = BATADV_IF_INACTIVE;
446         ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
447         if (ret < 0) {
448                 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
449                 bat_priv->num_ifaces--;
450                 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
451                 goto err_upper;
452         }
453
454         hard_iface->batman_adv_ptype.type = ethertype;
455         hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
456         hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
457         dev_add_pack(&hard_iface->batman_adv_ptype);
458
459         batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
460                     hard_iface->net_dev->name);
461
462         if (atomic_read(&bat_priv->fragmentation) &&
463             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
464                 batadv_info(hard_iface->soft_iface,
465                             "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to %i would solve the problem.\n",
466                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
467                             ETH_DATA_LEN + max_header_len);
468
469         if (!atomic_read(&bat_priv->fragmentation) &&
470             hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
471                 batadv_info(hard_iface->soft_iface,
472                             "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. If you experience problems getting traffic through try increasing the MTU to %i.\n",
473                             hard_iface->net_dev->name, hard_iface->net_dev->mtu,
474                             ETH_DATA_LEN + max_header_len);
475
476         if (batadv_hardif_is_iface_up(hard_iface))
477                 batadv_hardif_activate_interface(hard_iface);
478         else
479                 batadv_err(hard_iface->soft_iface,
480                            "Not using interface %s (retrying later): interface not active\n",
481                            hard_iface->net_dev->name);
482
483         /* begin scheduling originator messages on that interface */
484         batadv_schedule_bat_ogm(hard_iface);
485
486 out:
487         return 0;
488
489 err_upper:
490         netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
491 err_dev:
492         hard_iface->soft_iface = NULL;
493         dev_put(soft_iface);
494 err:
495         batadv_hardif_free_ref(hard_iface);
496         return ret;
497 }
498
499 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
500                                      enum batadv_hard_if_cleanup autodel)
501 {
502         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
503         struct batadv_hard_iface *primary_if = NULL;
504
505         if (hard_iface->if_status == BATADV_IF_ACTIVE)
506                 batadv_hardif_deactivate_interface(hard_iface);
507
508         if (hard_iface->if_status != BATADV_IF_INACTIVE)
509                 goto out;
510
511         batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
512                     hard_iface->net_dev->name);
513         dev_remove_pack(&hard_iface->batman_adv_ptype);
514
515         bat_priv->num_ifaces--;
516         batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
517
518         primary_if = batadv_primary_if_get_selected(bat_priv);
519         if (hard_iface == primary_if) {
520                 struct batadv_hard_iface *new_if;
521
522                 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
523                 batadv_primary_if_select(bat_priv, new_if);
524
525                 if (new_if)
526                         batadv_hardif_free_ref(new_if);
527         }
528
529         bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
530         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
531
532         /* delete all references to this hard_iface */
533         batadv_purge_orig_ref(bat_priv);
534         batadv_purge_outstanding_packets(bat_priv, hard_iface);
535         dev_put(hard_iface->soft_iface);
536
537         /* nobody uses this interface anymore */
538         if (!bat_priv->num_ifaces && autodel == BATADV_IF_CLEANUP_AUTO)
539                 batadv_softif_destroy_sysfs(hard_iface->soft_iface);
540
541         netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
542         hard_iface->soft_iface = NULL;
543         batadv_hardif_free_ref(hard_iface);
544
545 out:
546         if (primary_if)
547                 batadv_hardif_free_ref(primary_if);
548 }
549
550 /**
551  * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
552  * @work: work queue item
553  *
554  * Free the parts of the hard interface which can not be removed under
555  * rtnl lock (to prevent deadlock situations).
556  */
557 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
558 {
559         struct batadv_hard_iface *hard_iface;
560
561         hard_iface = container_of(work, struct batadv_hard_iface,
562                                   cleanup_work);
563
564         batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
565         batadv_hardif_free_ref(hard_iface);
566 }
567
568 static struct batadv_hard_iface *
569 batadv_hardif_add_interface(struct net_device *net_dev)
570 {
571         struct batadv_hard_iface *hard_iface;
572         int ret;
573
574         ASSERT_RTNL();
575
576         ret = batadv_is_valid_iface(net_dev);
577         if (ret != 1)
578                 goto out;
579
580         dev_hold(net_dev);
581
582         hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
583         if (!hard_iface)
584                 goto release_dev;
585
586         ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
587         if (ret)
588                 goto free_if;
589
590         hard_iface->if_num = -1;
591         hard_iface->net_dev = net_dev;
592         hard_iface->soft_iface = NULL;
593         hard_iface->if_status = BATADV_IF_NOT_IN_USE;
594         INIT_LIST_HEAD(&hard_iface->list);
595         INIT_WORK(&hard_iface->cleanup_work,
596                   batadv_hardif_remove_interface_finish);
597
598         hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
599         if (batadv_is_wifi_netdev(net_dev))
600                 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
601
602         /* extra reference for return */
603         atomic_set(&hard_iface->refcount, 2);
604
605         batadv_check_known_mac_addr(hard_iface->net_dev);
606         list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
607
608         return hard_iface;
609
610 free_if:
611         kfree(hard_iface);
612 release_dev:
613         dev_put(net_dev);
614 out:
615         return NULL;
616 }
617
618 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
619 {
620         ASSERT_RTNL();
621
622         /* first deactivate interface */
623         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
624                 batadv_hardif_disable_interface(hard_iface,
625                                                 BATADV_IF_CLEANUP_AUTO);
626
627         if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
628                 return;
629
630         hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
631         queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
632 }
633
634 void batadv_hardif_remove_interfaces(void)
635 {
636         struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
637
638         rtnl_lock();
639         list_for_each_entry_safe(hard_iface, hard_iface_tmp,
640                                  &batadv_hardif_list, list) {
641                 list_del_rcu(&hard_iface->list);
642                 batadv_hardif_remove_interface(hard_iface);
643         }
644         rtnl_unlock();
645 }
646
647 static int batadv_hard_if_event(struct notifier_block *this,
648                                 unsigned long event, void *ptr)
649 {
650         struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
651         struct batadv_hard_iface *hard_iface;
652         struct batadv_hard_iface *primary_if = NULL;
653         struct batadv_priv *bat_priv;
654
655         if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
656                 batadv_sysfs_add_meshif(net_dev);
657                 bat_priv = netdev_priv(net_dev);
658                 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
659                 return NOTIFY_DONE;
660         }
661
662         hard_iface = batadv_hardif_get_by_netdev(net_dev);
663         if (!hard_iface && event == NETDEV_REGISTER)
664                 hard_iface = batadv_hardif_add_interface(net_dev);
665
666         if (!hard_iface)
667                 goto out;
668
669         switch (event) {
670         case NETDEV_UP:
671                 batadv_hardif_activate_interface(hard_iface);
672                 break;
673         case NETDEV_GOING_DOWN:
674         case NETDEV_DOWN:
675                 batadv_hardif_deactivate_interface(hard_iface);
676                 break;
677         case NETDEV_UNREGISTER:
678                 list_del_rcu(&hard_iface->list);
679
680                 batadv_hardif_remove_interface(hard_iface);
681                 break;
682         case NETDEV_CHANGEMTU:
683                 if (hard_iface->soft_iface)
684                         batadv_update_min_mtu(hard_iface->soft_iface);
685                 break;
686         case NETDEV_CHANGEADDR:
687                 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
688                         goto hardif_put;
689
690                 batadv_check_known_mac_addr(hard_iface->net_dev);
691
692                 bat_priv = netdev_priv(hard_iface->soft_iface);
693                 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
694
695                 primary_if = batadv_primary_if_get_selected(bat_priv);
696                 if (!primary_if)
697                         goto hardif_put;
698
699                 if (hard_iface == primary_if)
700                         batadv_primary_if_update_addr(bat_priv, NULL);
701                 break;
702         default:
703                 break;
704         }
705
706 hardif_put:
707         batadv_hardif_free_ref(hard_iface);
708 out:
709         if (primary_if)
710                 batadv_hardif_free_ref(primary_if);
711         return NOTIFY_DONE;
712 }
713
714 struct notifier_block batadv_hard_if_notifier = {
715         .notifier_call = batadv_hard_if_event,
716 };