e9a5f8ca4c2718424bc0fafec5a9b7eabe6d65b1
[linux-2.6.git] / net / wireless / core.c
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2010          Johannes Berg <johannes@sipsolutions.net>
5  */
6
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9 #include <linux/if.h>
10 #include <linux/module.h>
11 #include <linux/err.h>
12 #include <linux/list.h>
13 #include <linux/slab.h>
14 #include <linux/nl80211.h>
15 #include <linux/debugfs.h>
16 #include <linux/notifier.h>
17 #include <linux/device.h>
18 #include <linux/etherdevice.h>
19 #include <linux/rtnetlink.h>
20 #include <linux/sched.h>
21 #include <net/genetlink.h>
22 #include <net/cfg80211.h>
23 #include "nl80211.h"
24 #include "core.h"
25 #include "sysfs.h"
26 #include "debugfs.h"
27 #include "wext-compat.h"
28 #include "ethtool.h"
29
30 /* name for sysfs, %d is appended */
31 #define PHY_NAME "phy"
32
33 MODULE_AUTHOR("Johannes Berg");
34 MODULE_LICENSE("GPL");
35 MODULE_DESCRIPTION("wireless configuration support");
36
37 /* RCU-protected (and cfg80211_mutex for writers) */
38 LIST_HEAD(cfg80211_rdev_list);
39 int cfg80211_rdev_list_generation;
40
41 DEFINE_MUTEX(cfg80211_mutex);
42
43 /* for debugfs */
44 static struct dentry *ieee80211_debugfs_dir;
45
46 /* for the cleanup, scan and event works */
47 struct workqueue_struct *cfg80211_wq;
48
49 /* requires cfg80211_mutex to be held! */
50 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
51 {
52         struct cfg80211_registered_device *result = NULL, *rdev;
53
54         if (!wiphy_idx_valid(wiphy_idx))
55                 return NULL;
56
57         assert_cfg80211_lock();
58
59         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
60                 if (rdev->wiphy_idx == wiphy_idx) {
61                         result = rdev;
62                         break;
63                 }
64         }
65
66         return result;
67 }
68
69 int get_wiphy_idx(struct wiphy *wiphy)
70 {
71         struct cfg80211_registered_device *rdev;
72         if (!wiphy)
73                 return WIPHY_IDX_STALE;
74         rdev = wiphy_to_dev(wiphy);
75         return rdev->wiphy_idx;
76 }
77
78 /* requires cfg80211_rdev_mutex to be held! */
79 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
80 {
81         struct cfg80211_registered_device *rdev;
82
83         if (!wiphy_idx_valid(wiphy_idx))
84                 return NULL;
85
86         assert_cfg80211_lock();
87
88         rdev = cfg80211_rdev_by_wiphy_idx(wiphy_idx);
89         if (!rdev)
90                 return NULL;
91         return &rdev->wiphy;
92 }
93
94 /* requires cfg80211_mutex to be held! */
95 struct cfg80211_registered_device *
96 __cfg80211_rdev_from_info(struct genl_info *info)
97 {
98         int ifindex;
99         struct cfg80211_registered_device *bywiphyidx = NULL, *byifidx = NULL;
100         struct net_device *dev;
101         int err = -EINVAL;
102
103         assert_cfg80211_lock();
104
105         if (info->attrs[NL80211_ATTR_WIPHY]) {
106                 bywiphyidx = cfg80211_rdev_by_wiphy_idx(
107                                 nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
108                 err = -ENODEV;
109         }
110
111         if (info->attrs[NL80211_ATTR_IFINDEX]) {
112                 ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
113                 dev = dev_get_by_index(genl_info_net(info), ifindex);
114                 if (dev) {
115                         if (dev->ieee80211_ptr)
116                                 byifidx =
117                                         wiphy_to_dev(dev->ieee80211_ptr->wiphy);
118                         dev_put(dev);
119                 }
120                 err = -ENODEV;
121         }
122
123         if (bywiphyidx && byifidx) {
124                 if (bywiphyidx != byifidx)
125                         return ERR_PTR(-EINVAL);
126                 else
127                         return bywiphyidx; /* == byifidx */
128         }
129         if (bywiphyidx)
130                 return bywiphyidx;
131
132         if (byifidx)
133                 return byifidx;
134
135         return ERR_PTR(err);
136 }
137
138 struct cfg80211_registered_device *
139 cfg80211_get_dev_from_info(struct genl_info *info)
140 {
141         struct cfg80211_registered_device *rdev;
142
143         mutex_lock(&cfg80211_mutex);
144         rdev = __cfg80211_rdev_from_info(info);
145
146         /* if it is not an error we grab the lock on
147          * it to assure it won't be going away while
148          * we operate on it */
149         if (!IS_ERR(rdev))
150                 mutex_lock(&rdev->mtx);
151
152         mutex_unlock(&cfg80211_mutex);
153
154         return rdev;
155 }
156
157 struct cfg80211_registered_device *
158 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
159 {
160         struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
161         struct net_device *dev;
162
163         mutex_lock(&cfg80211_mutex);
164         dev = dev_get_by_index(net, ifindex);
165         if (!dev)
166                 goto out;
167         if (dev->ieee80211_ptr) {
168                 rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
169                 mutex_lock(&rdev->mtx);
170         } else
171                 rdev = ERR_PTR(-ENODEV);
172         dev_put(dev);
173  out:
174         mutex_unlock(&cfg80211_mutex);
175         return rdev;
176 }
177
178 /* requires cfg80211_mutex to be held */
179 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
180                         char *newname)
181 {
182         struct cfg80211_registered_device *rdev2;
183         int wiphy_idx, taken = -1, result, digits;
184
185         assert_cfg80211_lock();
186
187         /* prohibit calling the thing phy%d when %d is not its number */
188         sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
189         if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
190                 /* count number of places needed to print wiphy_idx */
191                 digits = 1;
192                 while (wiphy_idx /= 10)
193                         digits++;
194                 /*
195                  * deny the name if it is phy<idx> where <idx> is printed
196                  * without leading zeroes. taken == strlen(newname) here
197                  */
198                 if (taken == strlen(PHY_NAME) + digits)
199                         return -EINVAL;
200         }
201
202
203         /* Ignore nop renames */
204         if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
205                 return 0;
206
207         /* Ensure another device does not already have this name. */
208         list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
209                 if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
210                         return -EINVAL;
211
212         result = device_rename(&rdev->wiphy.dev, newname);
213         if (result)
214                 return result;
215
216         if (rdev->wiphy.debugfsdir &&
217             !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
218                             rdev->wiphy.debugfsdir,
219                             rdev->wiphy.debugfsdir->d_parent,
220                             newname))
221                 pr_err("failed to rename debugfs dir to %s!\n", newname);
222
223         nl80211_notify_dev_rename(rdev);
224
225         return 0;
226 }
227
228 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
229                           struct net *net)
230 {
231         struct wireless_dev *wdev;
232         int err = 0;
233
234         if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
235                 return -EOPNOTSUPP;
236
237         list_for_each_entry(wdev, &rdev->netdev_list, list) {
238                 wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
239                 err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
240                 if (err)
241                         break;
242                 wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
243         }
244
245         if (err) {
246                 /* failed -- clean up to old netns */
247                 net = wiphy_net(&rdev->wiphy);
248
249                 list_for_each_entry_continue_reverse(wdev, &rdev->netdev_list,
250                                                      list) {
251                         wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
252                         err = dev_change_net_namespace(wdev->netdev, net,
253                                                         "wlan%d");
254                         WARN_ON(err);
255                         wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
256                 }
257
258                 return err;
259         }
260
261         wiphy_net_set(&rdev->wiphy, net);
262
263         err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
264         WARN_ON(err);
265
266         return 0;
267 }
268
269 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
270 {
271         struct cfg80211_registered_device *rdev = data;
272
273         rdev->ops->rfkill_poll(&rdev->wiphy);
274 }
275
276 static int cfg80211_rfkill_set_block(void *data, bool blocked)
277 {
278         struct cfg80211_registered_device *rdev = data;
279         struct wireless_dev *wdev;
280
281         if (!blocked)
282                 return 0;
283
284         rtnl_lock();
285         mutex_lock(&rdev->devlist_mtx);
286
287         list_for_each_entry(wdev, &rdev->netdev_list, list)
288                 dev_close(wdev->netdev);
289
290         mutex_unlock(&rdev->devlist_mtx);
291         rtnl_unlock();
292
293         return 0;
294 }
295
296 static void cfg80211_rfkill_sync_work(struct work_struct *work)
297 {
298         struct cfg80211_registered_device *rdev;
299
300         rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
301         cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
302 }
303
304 static void cfg80211_event_work(struct work_struct *work)
305 {
306         struct cfg80211_registered_device *rdev;
307
308         rdev = container_of(work, struct cfg80211_registered_device,
309                             event_work);
310
311         rtnl_lock();
312         cfg80211_lock_rdev(rdev);
313
314         cfg80211_process_rdev_events(rdev);
315         cfg80211_unlock_rdev(rdev);
316         rtnl_unlock();
317 }
318
319 /* exported functions */
320
321 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
322 {
323         static int wiphy_counter;
324
325         struct cfg80211_registered_device *rdev;
326         int alloc_size;
327
328         WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
329         WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
330         WARN_ON(ops->connect && !ops->disconnect);
331         WARN_ON(ops->join_ibss && !ops->leave_ibss);
332         WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
333         WARN_ON(ops->add_station && !ops->del_station);
334         WARN_ON(ops->add_mpath && !ops->del_mpath);
335         WARN_ON(ops->join_mesh && !ops->leave_mesh);
336
337         alloc_size = sizeof(*rdev) + sizeof_priv;
338
339         rdev = kzalloc(alloc_size, GFP_KERNEL);
340         if (!rdev)
341                 return NULL;
342
343         rdev->ops = ops;
344
345         mutex_lock(&cfg80211_mutex);
346
347         rdev->wiphy_idx = wiphy_counter++;
348
349         if (unlikely(!wiphy_idx_valid(rdev->wiphy_idx))) {
350                 wiphy_counter--;
351                 mutex_unlock(&cfg80211_mutex);
352                 /* ugh, wrapped! */
353                 kfree(rdev);
354                 return NULL;
355         }
356
357         mutex_unlock(&cfg80211_mutex);
358
359         /* give it a proper name */
360         dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
361
362         mutex_init(&rdev->mtx);
363         mutex_init(&rdev->devlist_mtx);
364         INIT_LIST_HEAD(&rdev->netdev_list);
365         spin_lock_init(&rdev->bss_lock);
366         INIT_LIST_HEAD(&rdev->bss_list);
367         INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
368
369 #ifdef CONFIG_CFG80211_WEXT
370         rdev->wiphy.wext = &cfg80211_wext_handler;
371 #endif
372
373         device_initialize(&rdev->wiphy.dev);
374         rdev->wiphy.dev.class = &ieee80211_class;
375         rdev->wiphy.dev.platform_data = rdev;
376
377 #ifdef CONFIG_CFG80211_DEFAULT_PS
378         rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
379 #endif
380
381         wiphy_net_set(&rdev->wiphy, &init_net);
382
383         rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
384         rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
385                                    &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
386                                    &rdev->rfkill_ops, rdev);
387
388         if (!rdev->rfkill) {
389                 kfree(rdev);
390                 return NULL;
391         }
392
393         INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
394         INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
395         INIT_WORK(&rdev->event_work, cfg80211_event_work);
396
397         init_waitqueue_head(&rdev->dev_wait);
398
399         /*
400          * Initialize wiphy parameters to IEEE 802.11 MIB default values.
401          * Fragmentation and RTS threshold are disabled by default with the
402          * special -1 value.
403          */
404         rdev->wiphy.retry_short = 7;
405         rdev->wiphy.retry_long = 4;
406         rdev->wiphy.frag_threshold = (u32) -1;
407         rdev->wiphy.rts_threshold = (u32) -1;
408         rdev->wiphy.coverage_class = 0;
409
410         return &rdev->wiphy;
411 }
412 EXPORT_SYMBOL(wiphy_new);
413
414 int wiphy_register(struct wiphy *wiphy)
415 {
416         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
417         int res;
418         enum ieee80211_band band;
419         struct ieee80211_supported_band *sband;
420         bool have_band = false;
421         int i;
422         u16 ifmodes = wiphy->interface_modes;
423
424         if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
425                 return -EINVAL;
426
427         if (WARN_ON(wiphy->addresses &&
428                     !is_zero_ether_addr(wiphy->perm_addr) &&
429                     memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
430                            ETH_ALEN)))
431                 return -EINVAL;
432
433         if (wiphy->addresses)
434                 memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
435
436         /* sanity check ifmodes */
437         WARN_ON(!ifmodes);
438         ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
439         if (WARN_ON(ifmodes != wiphy->interface_modes))
440                 wiphy->interface_modes = ifmodes;
441
442         /* sanity check supported bands/channels */
443         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
444                 sband = wiphy->bands[band];
445                 if (!sband)
446                         continue;
447
448                 sband->band = band;
449
450                 if (WARN_ON(!sband->n_channels || !sband->n_bitrates))
451                         return -EINVAL;
452
453                 /*
454                  * Since we use a u32 for rate bitmaps in
455                  * ieee80211_get_response_rate, we cannot
456                  * have more than 32 legacy rates.
457                  */
458                 if (WARN_ON(sband->n_bitrates > 32))
459                         return -EINVAL;
460
461                 for (i = 0; i < sband->n_channels; i++) {
462                         sband->channels[i].orig_flags =
463                                 sband->channels[i].flags;
464                         sband->channels[i].orig_mag =
465                                 sband->channels[i].max_antenna_gain;
466                         sband->channels[i].orig_mpwr =
467                                 sband->channels[i].max_power;
468                         sband->channels[i].band = band;
469                 }
470
471                 have_band = true;
472         }
473
474         if (!have_band) {
475                 WARN_ON(1);
476                 return -EINVAL;
477         }
478
479         /* check and set up bitrates */
480         ieee80211_set_bitrate_flags(wiphy);
481
482         mutex_lock(&cfg80211_mutex);
483
484         res = device_add(&rdev->wiphy.dev);
485         if (res) {
486                 mutex_unlock(&cfg80211_mutex);
487                 return res;
488         }
489
490         /* set up regulatory info */
491         wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
492
493         list_add_rcu(&rdev->list, &cfg80211_rdev_list);
494         cfg80211_rdev_list_generation++;
495
496         /* add to debugfs */
497         rdev->wiphy.debugfsdir =
498                 debugfs_create_dir(wiphy_name(&rdev->wiphy),
499                                    ieee80211_debugfs_dir);
500         if (IS_ERR(rdev->wiphy.debugfsdir))
501                 rdev->wiphy.debugfsdir = NULL;
502
503         if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
504                 struct regulatory_request request;
505
506                 request.wiphy_idx = get_wiphy_idx(wiphy);
507                 request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
508                 request.alpha2[0] = '9';
509                 request.alpha2[1] = '9';
510
511                 nl80211_send_reg_change_event(&request);
512         }
513
514         cfg80211_debugfs_rdev_add(rdev);
515         mutex_unlock(&cfg80211_mutex);
516
517         /*
518          * due to a locking dependency this has to be outside of the
519          * cfg80211_mutex lock
520          */
521         res = rfkill_register(rdev->rfkill);
522         if (res)
523                 goto out_rm_dev;
524
525         return 0;
526
527 out_rm_dev:
528         device_del(&rdev->wiphy.dev);
529         return res;
530 }
531 EXPORT_SYMBOL(wiphy_register);
532
533 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
534 {
535         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
536
537         if (!rdev->ops->rfkill_poll)
538                 return;
539         rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
540         rfkill_resume_polling(rdev->rfkill);
541 }
542 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
543
544 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
545 {
546         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
547
548         rfkill_pause_polling(rdev->rfkill);
549 }
550 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
551
552 void wiphy_unregister(struct wiphy *wiphy)
553 {
554         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
555
556         rfkill_unregister(rdev->rfkill);
557
558         /* protect the device list */
559         mutex_lock(&cfg80211_mutex);
560
561         wait_event(rdev->dev_wait, ({
562                 int __count;
563                 mutex_lock(&rdev->devlist_mtx);
564                 __count = rdev->opencount;
565                 mutex_unlock(&rdev->devlist_mtx);
566                 __count == 0;}));
567
568         mutex_lock(&rdev->devlist_mtx);
569         BUG_ON(!list_empty(&rdev->netdev_list));
570         mutex_unlock(&rdev->devlist_mtx);
571
572         /*
573          * First remove the hardware from everywhere, this makes
574          * it impossible to find from userspace.
575          */
576         debugfs_remove_recursive(rdev->wiphy.debugfsdir);
577         list_del_rcu(&rdev->list);
578         synchronize_rcu();
579
580         /*
581          * Try to grab rdev->mtx. If a command is still in progress,
582          * hopefully the driver will refuse it since it's tearing
583          * down the device already. We wait for this command to complete
584          * before unlinking the item from the list.
585          * Note: as codified by the BUG_ON above we cannot get here if
586          * a virtual interface is still present. Hence, we can only get
587          * to lock contention here if userspace issues a command that
588          * identified the hardware by wiphy index.
589          */
590         cfg80211_lock_rdev(rdev);
591         /* nothing */
592         cfg80211_unlock_rdev(rdev);
593
594         /* If this device got a regulatory hint tell core its
595          * free to listen now to a new shiny device regulatory hint */
596         reg_device_remove(wiphy);
597
598         cfg80211_rdev_list_generation++;
599         device_del(&rdev->wiphy.dev);
600
601         mutex_unlock(&cfg80211_mutex);
602
603         flush_work(&rdev->scan_done_wk);
604         cancel_work_sync(&rdev->conn_work);
605         flush_work(&rdev->event_work);
606 }
607 EXPORT_SYMBOL(wiphy_unregister);
608
609 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
610 {
611         struct cfg80211_internal_bss *scan, *tmp;
612         rfkill_destroy(rdev->rfkill);
613         mutex_destroy(&rdev->mtx);
614         mutex_destroy(&rdev->devlist_mtx);
615         list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
616                 cfg80211_put_bss(&scan->pub);
617         kfree(rdev);
618 }
619
620 void wiphy_free(struct wiphy *wiphy)
621 {
622         put_device(&wiphy->dev);
623 }
624 EXPORT_SYMBOL(wiphy_free);
625
626 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
627 {
628         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
629
630         if (rfkill_set_hw_state(rdev->rfkill, blocked))
631                 schedule_work(&rdev->rfkill_sync);
632 }
633 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
634
635 static void wdev_cleanup_work(struct work_struct *work)
636 {
637         struct wireless_dev *wdev;
638         struct cfg80211_registered_device *rdev;
639
640         wdev = container_of(work, struct wireless_dev, cleanup_work);
641         rdev = wiphy_to_dev(wdev->wiphy);
642
643         cfg80211_lock_rdev(rdev);
644
645         if (WARN_ON(rdev->scan_req && rdev->scan_req->dev == wdev->netdev)) {
646                 rdev->scan_req->aborted = true;
647                 ___cfg80211_scan_done(rdev, true);
648         }
649
650         cfg80211_unlock_rdev(rdev);
651
652         mutex_lock(&rdev->devlist_mtx);
653         rdev->opencount--;
654         mutex_unlock(&rdev->devlist_mtx);
655         wake_up(&rdev->dev_wait);
656
657         dev_put(wdev->netdev);
658 }
659
660 static struct device_type wiphy_type = {
661         .name   = "wlan",
662 };
663
664 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
665                                          unsigned long state,
666                                          void *ndev)
667 {
668         struct net_device *dev = ndev;
669         struct wireless_dev *wdev = dev->ieee80211_ptr;
670         struct cfg80211_registered_device *rdev;
671
672         if (!wdev)
673                 return NOTIFY_DONE;
674
675         rdev = wiphy_to_dev(wdev->wiphy);
676
677         WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
678
679         switch (state) {
680         case NETDEV_POST_INIT:
681                 SET_NETDEV_DEVTYPE(dev, &wiphy_type);
682                 break;
683         case NETDEV_REGISTER:
684                 /*
685                  * NB: cannot take rdev->mtx here because this may be
686                  * called within code protected by it when interfaces
687                  * are added with nl80211.
688                  */
689                 mutex_init(&wdev->mtx);
690                 INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
691                 INIT_LIST_HEAD(&wdev->event_list);
692                 spin_lock_init(&wdev->event_lock);
693                 INIT_LIST_HEAD(&wdev->mgmt_registrations);
694                 spin_lock_init(&wdev->mgmt_registrations_lock);
695
696                 mutex_lock(&rdev->devlist_mtx);
697                 list_add_rcu(&wdev->list, &rdev->netdev_list);
698                 rdev->devlist_generation++;
699                 /* can only change netns with wiphy */
700                 dev->features |= NETIF_F_NETNS_LOCAL;
701
702                 if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
703                                       "phy80211")) {
704                         pr_err("failed to add phy80211 symlink to netdev!\n");
705                 }
706                 wdev->netdev = dev;
707                 wdev->sme_state = CFG80211_SME_IDLE;
708                 mutex_unlock(&rdev->devlist_mtx);
709 #ifdef CONFIG_CFG80211_WEXT
710                 wdev->wext.default_key = -1;
711                 wdev->wext.default_mgmt_key = -1;
712                 wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
713 #endif
714
715                 if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
716                         wdev->ps = true;
717                 else
718                         wdev->ps = false;
719                 /* allow mac80211 to determine the timeout */
720                 wdev->ps_timeout = -1;
721                 if (rdev->ops->set_power_mgmt)
722                         if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
723                                                       wdev->ps,
724                                                       wdev->ps_timeout)) {
725                                 /* assume this means it's off */
726                                 wdev->ps = false;
727                         }
728
729                 if (!dev->ethtool_ops)
730                         dev->ethtool_ops = &cfg80211_ethtool_ops;
731
732                 if ((wdev->iftype == NL80211_IFTYPE_STATION ||
733                      wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
734                      wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
735                         dev->priv_flags |= IFF_DONT_BRIDGE;
736                 break;
737         case NETDEV_GOING_DOWN:
738                 switch (wdev->iftype) {
739                 case NL80211_IFTYPE_ADHOC:
740                         cfg80211_leave_ibss(rdev, dev, true);
741                         break;
742                 case NL80211_IFTYPE_P2P_CLIENT:
743                 case NL80211_IFTYPE_STATION:
744                         wdev_lock(wdev);
745 #ifdef CONFIG_CFG80211_WEXT
746                         kfree(wdev->wext.ie);
747                         wdev->wext.ie = NULL;
748                         wdev->wext.ie_len = 0;
749                         wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
750 #endif
751                         __cfg80211_disconnect(rdev, dev,
752                                               WLAN_REASON_DEAUTH_LEAVING, true);
753                         cfg80211_mlme_down(rdev, dev);
754                         wdev_unlock(wdev);
755                         break;
756                 case NL80211_IFTYPE_MESH_POINT:
757                         cfg80211_leave_mesh(rdev, dev);
758                         break;
759                 default:
760                         break;
761                 }
762                 break;
763         case NETDEV_DOWN:
764                 dev_hold(dev);
765                 queue_work(cfg80211_wq, &wdev->cleanup_work);
766                 break;
767         case NETDEV_UP:
768                 /*
769                  * If we have a really quick DOWN/UP succession we may
770                  * have this work still pending ... cancel it and see
771                  * if it was pending, in which case we need to account
772                  * for some of the work it would have done.
773                  */
774                 if (cancel_work_sync(&wdev->cleanup_work)) {
775                         mutex_lock(&rdev->devlist_mtx);
776                         rdev->opencount--;
777                         mutex_unlock(&rdev->devlist_mtx);
778                         dev_put(dev);
779                 }
780                 cfg80211_lock_rdev(rdev);
781                 mutex_lock(&rdev->devlist_mtx);
782                 wdev_lock(wdev);
783                 switch (wdev->iftype) {
784 #ifdef CONFIG_CFG80211_WEXT
785                 case NL80211_IFTYPE_ADHOC:
786                         cfg80211_ibss_wext_join(rdev, wdev);
787                         break;
788                 case NL80211_IFTYPE_STATION:
789                         cfg80211_mgd_wext_connect(rdev, wdev);
790                         break;
791 #endif
792 #ifdef CONFIG_MAC80211_MESH
793                 case NL80211_IFTYPE_MESH_POINT:
794                         {
795                                 /* backward compat code... */
796                                 struct mesh_setup setup;
797                                 memcpy(&setup, &default_mesh_setup,
798                                                 sizeof(setup));
799                                  /* back compat only needed for mesh_id */
800                                 setup.mesh_id = wdev->ssid;
801                                 setup.mesh_id_len = wdev->mesh_id_up_len;
802                                 if (wdev->mesh_id_up_len)
803                                         __cfg80211_join_mesh(rdev, dev,
804                                                         &setup,
805                                                         &default_mesh_config);
806                                 break;
807                         }
808 #endif
809                 default:
810                         break;
811                 }
812                 wdev_unlock(wdev);
813                 rdev->opencount++;
814                 mutex_unlock(&rdev->devlist_mtx);
815                 cfg80211_unlock_rdev(rdev);
816                 break;
817         case NETDEV_UNREGISTER:
818                 /*
819                  * NB: cannot take rdev->mtx here because this may be
820                  * called within code protected by it when interfaces
821                  * are removed with nl80211.
822                  */
823                 mutex_lock(&rdev->devlist_mtx);
824                 /*
825                  * It is possible to get NETDEV_UNREGISTER
826                  * multiple times. To detect that, check
827                  * that the interface is still on the list
828                  * of registered interfaces, and only then
829                  * remove and clean it up.
830                  */
831                 if (!list_empty(&wdev->list)) {
832                         sysfs_remove_link(&dev->dev.kobj, "phy80211");
833                         list_del_rcu(&wdev->list);
834                         rdev->devlist_generation++;
835                         cfg80211_mlme_purge_registrations(wdev);
836 #ifdef CONFIG_CFG80211_WEXT
837                         kfree(wdev->wext.keys);
838 #endif
839                 }
840                 mutex_unlock(&rdev->devlist_mtx);
841                 /*
842                  * synchronise (so that we won't find this netdev
843                  * from other code any more) and then clear the list
844                  * head so that the above code can safely check for
845                  * !list_empty() to avoid double-cleanup.
846                  */
847                 synchronize_rcu();
848                 INIT_LIST_HEAD(&wdev->list);
849                 break;
850         case NETDEV_PRE_UP:
851                 if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
852                         return notifier_from_errno(-EOPNOTSUPP);
853                 if (rfkill_blocked(rdev->rfkill))
854                         return notifier_from_errno(-ERFKILL);
855                 break;
856         }
857
858         return NOTIFY_DONE;
859 }
860
861 static struct notifier_block cfg80211_netdev_notifier = {
862         .notifier_call = cfg80211_netdev_notifier_call,
863 };
864
865 static void __net_exit cfg80211_pernet_exit(struct net *net)
866 {
867         struct cfg80211_registered_device *rdev;
868
869         rtnl_lock();
870         mutex_lock(&cfg80211_mutex);
871         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
872                 if (net_eq(wiphy_net(&rdev->wiphy), net))
873                         WARN_ON(cfg80211_switch_netns(rdev, &init_net));
874         }
875         mutex_unlock(&cfg80211_mutex);
876         rtnl_unlock();
877 }
878
879 static struct pernet_operations cfg80211_pernet_ops = {
880         .exit = cfg80211_pernet_exit,
881 };
882
883 static int __init cfg80211_init(void)
884 {
885         int err;
886
887         err = register_pernet_device(&cfg80211_pernet_ops);
888         if (err)
889                 goto out_fail_pernet;
890
891         err = wiphy_sysfs_init();
892         if (err)
893                 goto out_fail_sysfs;
894
895         err = register_netdevice_notifier(&cfg80211_netdev_notifier);
896         if (err)
897                 goto out_fail_notifier;
898
899         err = nl80211_init();
900         if (err)
901                 goto out_fail_nl80211;
902
903         ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
904
905         err = regulatory_init();
906         if (err)
907                 goto out_fail_reg;
908
909         cfg80211_wq = create_singlethread_workqueue("cfg80211");
910         if (!cfg80211_wq)
911                 goto out_fail_wq;
912
913         return 0;
914
915 out_fail_wq:
916         regulatory_exit();
917 out_fail_reg:
918         debugfs_remove(ieee80211_debugfs_dir);
919 out_fail_nl80211:
920         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
921 out_fail_notifier:
922         wiphy_sysfs_exit();
923 out_fail_sysfs:
924         unregister_pernet_device(&cfg80211_pernet_ops);
925 out_fail_pernet:
926         return err;
927 }
928 subsys_initcall(cfg80211_init);
929
930 static void __exit cfg80211_exit(void)
931 {
932         debugfs_remove(ieee80211_debugfs_dir);
933         nl80211_exit();
934         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
935         wiphy_sysfs_exit();
936         regulatory_exit();
937         unregister_pernet_device(&cfg80211_pernet_ops);
938         destroy_workqueue(cfg80211_wq);
939 }
940 module_exit(cfg80211_exit);