Linux 3.2.102
[pandora-kernel.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 static bool cfg80211_disable_40mhz_24ghz;
50 module_param(cfg80211_disable_40mhz_24ghz, bool, 0644);
51 MODULE_PARM_DESC(cfg80211_disable_40mhz_24ghz,
52                  "Disable 40MHz support in the 2.4GHz band");
53
54 /* requires cfg80211_mutex to be held! */
55 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
56 {
57         struct cfg80211_registered_device *result = NULL, *rdev;
58
59         if (!wiphy_idx_valid(wiphy_idx))
60                 return NULL;
61
62         assert_cfg80211_lock();
63
64         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
65                 if (rdev->wiphy_idx == wiphy_idx) {
66                         result = rdev;
67                         break;
68                 }
69         }
70
71         return result;
72 }
73
74 int get_wiphy_idx(struct wiphy *wiphy)
75 {
76         struct cfg80211_registered_device *rdev;
77         if (!wiphy)
78                 return WIPHY_IDX_STALE;
79         rdev = wiphy_to_dev(wiphy);
80         return rdev->wiphy_idx;
81 }
82
83 /* requires cfg80211_rdev_mutex to be held! */
84 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
85 {
86         struct cfg80211_registered_device *rdev;
87
88         if (!wiphy_idx_valid(wiphy_idx))
89                 return NULL;
90
91         assert_cfg80211_lock();
92
93         rdev = cfg80211_rdev_by_wiphy_idx(wiphy_idx);
94         if (!rdev)
95                 return NULL;
96         return &rdev->wiphy;
97 }
98
99 /* requires cfg80211_mutex to be held! */
100 struct cfg80211_registered_device *
101 __cfg80211_rdev_from_info(struct genl_info *info)
102 {
103         int ifindex;
104         struct cfg80211_registered_device *bywiphyidx = NULL, *byifidx = NULL;
105         struct net_device *dev;
106         int err = -EINVAL;
107
108         assert_cfg80211_lock();
109
110         if (info->attrs[NL80211_ATTR_WIPHY]) {
111                 bywiphyidx = cfg80211_rdev_by_wiphy_idx(
112                                 nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
113                 err = -ENODEV;
114         }
115
116         if (info->attrs[NL80211_ATTR_IFINDEX]) {
117                 ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
118                 dev = dev_get_by_index(genl_info_net(info), ifindex);
119                 if (dev) {
120                         if (dev->ieee80211_ptr)
121                                 byifidx =
122                                         wiphy_to_dev(dev->ieee80211_ptr->wiphy);
123                         dev_put(dev);
124                 }
125                 err = -ENODEV;
126         }
127
128         if (bywiphyidx && byifidx) {
129                 if (bywiphyidx != byifidx)
130                         return ERR_PTR(-EINVAL);
131                 else
132                         return bywiphyidx; /* == byifidx */
133         }
134         if (bywiphyidx)
135                 return bywiphyidx;
136
137         if (byifidx)
138                 return byifidx;
139
140         return ERR_PTR(err);
141 }
142
143 struct cfg80211_registered_device *
144 cfg80211_get_dev_from_info(struct genl_info *info)
145 {
146         struct cfg80211_registered_device *rdev;
147
148         mutex_lock(&cfg80211_mutex);
149         rdev = __cfg80211_rdev_from_info(info);
150
151         /* if it is not an error we grab the lock on
152          * it to assure it won't be going away while
153          * we operate on it */
154         if (!IS_ERR(rdev))
155                 mutex_lock(&rdev->mtx);
156
157         mutex_unlock(&cfg80211_mutex);
158
159         return rdev;
160 }
161
162 struct cfg80211_registered_device *
163 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
164 {
165         struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
166         struct net_device *dev;
167
168         mutex_lock(&cfg80211_mutex);
169         dev = dev_get_by_index(net, ifindex);
170         if (!dev)
171                 goto out;
172         if (dev->ieee80211_ptr) {
173                 rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
174                 mutex_lock(&rdev->mtx);
175         } else
176                 rdev = ERR_PTR(-ENODEV);
177         dev_put(dev);
178  out:
179         mutex_unlock(&cfg80211_mutex);
180         return rdev;
181 }
182
183 /* requires cfg80211_mutex to be held */
184 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
185                         char *newname)
186 {
187         struct cfg80211_registered_device *rdev2;
188         int wiphy_idx, taken = -1, result, digits;
189
190         assert_cfg80211_lock();
191
192         /* prohibit calling the thing phy%d when %d is not its number */
193         sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
194         if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
195                 /* count number of places needed to print wiphy_idx */
196                 digits = 1;
197                 while (wiphy_idx /= 10)
198                         digits++;
199                 /*
200                  * deny the name if it is phy<idx> where <idx> is printed
201                  * without leading zeroes. taken == strlen(newname) here
202                  */
203                 if (taken == strlen(PHY_NAME) + digits)
204                         return -EINVAL;
205         }
206
207
208         /* Ignore nop renames */
209         if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
210                 return 0;
211
212         /* Ensure another device does not already have this name. */
213         list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
214                 if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
215                         return -EINVAL;
216
217         result = device_rename(&rdev->wiphy.dev, newname);
218         if (result)
219                 return result;
220
221         if (rdev->wiphy.debugfsdir &&
222             !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
223                             rdev->wiphy.debugfsdir,
224                             rdev->wiphy.debugfsdir->d_parent,
225                             newname))
226                 pr_err("failed to rename debugfs dir to %s!\n", newname);
227
228         nl80211_notify_dev_rename(rdev);
229
230         return 0;
231 }
232
233 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
234                           struct net *net)
235 {
236         struct wireless_dev *wdev;
237         int err = 0;
238
239         if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
240                 return -EOPNOTSUPP;
241
242         list_for_each_entry(wdev, &rdev->netdev_list, list) {
243                 wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
244                 err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
245                 if (err)
246                         break;
247                 wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
248         }
249
250         if (err) {
251                 /* failed -- clean up to old netns */
252                 net = wiphy_net(&rdev->wiphy);
253
254                 list_for_each_entry_continue_reverse(wdev, &rdev->netdev_list,
255                                                      list) {
256                         wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
257                         err = dev_change_net_namespace(wdev->netdev, net,
258                                                         "wlan%d");
259                         WARN_ON(err);
260                         wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
261                 }
262
263                 return err;
264         }
265
266         wiphy_net_set(&rdev->wiphy, net);
267
268         err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
269         WARN_ON(err);
270
271         return 0;
272 }
273
274 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
275 {
276         struct cfg80211_registered_device *rdev = data;
277
278         rdev->ops->rfkill_poll(&rdev->wiphy);
279 }
280
281 static int cfg80211_rfkill_set_block(void *data, bool blocked)
282 {
283         struct cfg80211_registered_device *rdev = data;
284         struct wireless_dev *wdev;
285
286         if (!blocked)
287                 return 0;
288
289         rtnl_lock();
290         mutex_lock(&rdev->devlist_mtx);
291
292         list_for_each_entry(wdev, &rdev->netdev_list, list)
293                 dev_close(wdev->netdev);
294
295         mutex_unlock(&rdev->devlist_mtx);
296         rtnl_unlock();
297
298         return 0;
299 }
300
301 static void cfg80211_rfkill_sync_work(struct work_struct *work)
302 {
303         struct cfg80211_registered_device *rdev;
304
305         rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
306         cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
307 }
308
309 static void cfg80211_event_work(struct work_struct *work)
310 {
311         struct cfg80211_registered_device *rdev;
312
313         rdev = container_of(work, struct cfg80211_registered_device,
314                             event_work);
315
316         rtnl_lock();
317         cfg80211_lock_rdev(rdev);
318
319         cfg80211_process_rdev_events(rdev);
320         cfg80211_unlock_rdev(rdev);
321         rtnl_unlock();
322 }
323
324 /* exported functions */
325
326 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
327 {
328         static int wiphy_counter;
329
330         struct cfg80211_registered_device *rdev;
331         int alloc_size;
332         int rv;
333
334         WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
335         WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
336         WARN_ON(ops->connect && !ops->disconnect);
337         WARN_ON(ops->join_ibss && !ops->leave_ibss);
338         WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
339         WARN_ON(ops->add_station && !ops->del_station);
340         WARN_ON(ops->add_mpath && !ops->del_mpath);
341         WARN_ON(ops->join_mesh && !ops->leave_mesh);
342
343         alloc_size = sizeof(*rdev) + sizeof_priv;
344
345         rdev = kzalloc(alloc_size, GFP_KERNEL);
346         if (!rdev)
347                 return NULL;
348
349         rdev->ops = ops;
350
351         mutex_lock(&cfg80211_mutex);
352
353         rdev->wiphy_idx = wiphy_counter++;
354
355         if (unlikely(!wiphy_idx_valid(rdev->wiphy_idx))) {
356                 wiphy_counter--;
357                 mutex_unlock(&cfg80211_mutex);
358                 /* ugh, wrapped! */
359                 kfree(rdev);
360                 return NULL;
361         }
362
363         mutex_unlock(&cfg80211_mutex);
364
365         /* give it a proper name */
366         rv = dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
367         if (rv < 0) {
368                 kfree(rdev);
369                 return NULL;
370         }
371
372         mutex_init(&rdev->mtx);
373         mutex_init(&rdev->devlist_mtx);
374         mutex_init(&rdev->sched_scan_mtx);
375         INIT_LIST_HEAD(&rdev->netdev_list);
376         spin_lock_init(&rdev->bss_lock);
377         INIT_LIST_HEAD(&rdev->bss_list);
378         INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
379         INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
380 #ifdef CONFIG_CFG80211_WEXT
381         rdev->wiphy.wext = &cfg80211_wext_handler;
382 #endif
383
384         device_initialize(&rdev->wiphy.dev);
385         rdev->wiphy.dev.class = &ieee80211_class;
386         rdev->wiphy.dev.platform_data = rdev;
387
388 #ifdef CONFIG_CFG80211_DEFAULT_PS
389         rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
390 #endif
391
392         wiphy_net_set(&rdev->wiphy, &init_net);
393
394         rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
395         rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
396                                    &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
397                                    &rdev->rfkill_ops, rdev);
398
399         if (!rdev->rfkill) {
400                 kfree(rdev);
401                 return NULL;
402         }
403
404         INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
405         INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
406         INIT_WORK(&rdev->event_work, cfg80211_event_work);
407
408         init_waitqueue_head(&rdev->dev_wait);
409
410         /*
411          * Initialize wiphy parameters to IEEE 802.11 MIB default values.
412          * Fragmentation and RTS threshold are disabled by default with the
413          * special -1 value.
414          */
415         rdev->wiphy.retry_short = 7;
416         rdev->wiphy.retry_long = 4;
417         rdev->wiphy.frag_threshold = (u32) -1;
418         rdev->wiphy.rts_threshold = (u32) -1;
419         rdev->wiphy.coverage_class = 0;
420
421         return &rdev->wiphy;
422 }
423 EXPORT_SYMBOL(wiphy_new);
424
425 static int wiphy_verify_combinations(struct wiphy *wiphy)
426 {
427         const struct ieee80211_iface_combination *c;
428         int i, j;
429
430         /* If we have combinations enforce them */
431         if (wiphy->n_iface_combinations)
432                 wiphy->flags |= WIPHY_FLAG_ENFORCE_COMBINATIONS;
433
434         for (i = 0; i < wiphy->n_iface_combinations; i++) {
435                 u32 cnt = 0;
436                 u16 all_iftypes = 0;
437
438                 c = &wiphy->iface_combinations[i];
439
440                 /* Combinations with just one interface aren't real */
441                 if (WARN_ON(c->max_interfaces < 2))
442                         return -EINVAL;
443
444                 /* Need at least one channel */
445                 if (WARN_ON(!c->num_different_channels))
446                         return -EINVAL;
447
448                 if (WARN_ON(!c->n_limits))
449                         return -EINVAL;
450
451                 for (j = 0; j < c->n_limits; j++) {
452                         u16 types = c->limits[j].types;
453
454                         /*
455                          * interface types shouldn't overlap, this is
456                          * used in cfg80211_can_change_interface()
457                          */
458                         if (WARN_ON(types & all_iftypes))
459                                 return -EINVAL;
460                         all_iftypes |= types;
461
462                         if (WARN_ON(!c->limits[j].max))
463                                 return -EINVAL;
464
465                         /* Shouldn't list software iftypes in combinations! */
466                         if (WARN_ON(wiphy->software_iftypes & types))
467                                 return -EINVAL;
468
469                         cnt += c->limits[j].max;
470                         /*
471                          * Don't advertise an unsupported type
472                          * in a combination.
473                          */
474                         if (WARN_ON((wiphy->interface_modes & types) != types))
475                                 return -EINVAL;
476                 }
477
478                 /* You can't even choose that many! */
479                 if (WARN_ON(cnt < c->max_interfaces))
480                         return -EINVAL;
481         }
482
483         return 0;
484 }
485
486 int wiphy_register(struct wiphy *wiphy)
487 {
488         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
489         int res;
490         enum ieee80211_band band;
491         struct ieee80211_supported_band *sband;
492         bool have_band = false;
493         int i;
494         u16 ifmodes = wiphy->interface_modes;
495
496         if (WARN_ON((wiphy->wowlan.flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
497                     !(wiphy->wowlan.flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
498                 return -EINVAL;
499
500         if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
501                 return -EINVAL;
502
503         if (WARN_ON(wiphy->addresses &&
504                     !is_zero_ether_addr(wiphy->perm_addr) &&
505                     memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
506                            ETH_ALEN)))
507                 return -EINVAL;
508
509         if (wiphy->addresses)
510                 memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
511
512         /* sanity check ifmodes */
513         WARN_ON(!ifmodes);
514         ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
515         if (WARN_ON(ifmodes != wiphy->interface_modes))
516                 wiphy->interface_modes = ifmodes;
517
518         res = wiphy_verify_combinations(wiphy);
519         if (res)
520                 return res;
521
522         /* sanity check supported bands/channels */
523         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
524                 sband = wiphy->bands[band];
525                 if (!sband)
526                         continue;
527
528                 sband->band = band;
529
530                 if (WARN_ON(!sband->n_channels || !sband->n_bitrates))
531                         return -EINVAL;
532
533                 /*
534                  * Since cfg80211_disable_40mhz_24ghz is global, we can
535                  * modify the sband's ht data even if the driver uses a
536                  * global structure for that.
537                  */
538                 if (cfg80211_disable_40mhz_24ghz &&
539                     band == IEEE80211_BAND_2GHZ &&
540                     sband->ht_cap.ht_supported) {
541                         sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
542                         sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
543                 }
544
545                 /*
546                  * Since we use a u32 for rate bitmaps in
547                  * ieee80211_get_response_rate, we cannot
548                  * have more than 32 legacy rates.
549                  */
550                 if (WARN_ON(sband->n_bitrates > 32))
551                         return -EINVAL;
552
553                 for (i = 0; i < sband->n_channels; i++) {
554                         sband->channels[i].orig_flags =
555                                 sband->channels[i].flags;
556                         sband->channels[i].orig_mag = INT_MAX;
557                         sband->channels[i].orig_mpwr =
558                                 sband->channels[i].max_power;
559                         sband->channels[i].band = band;
560                 }
561
562                 have_band = true;
563         }
564
565         if (!have_band) {
566                 WARN_ON(1);
567                 return -EINVAL;
568         }
569
570         if (rdev->wiphy.wowlan.n_patterns) {
571                 if (WARN_ON(!rdev->wiphy.wowlan.pattern_min_len ||
572                             rdev->wiphy.wowlan.pattern_min_len >
573                             rdev->wiphy.wowlan.pattern_max_len))
574                         return -EINVAL;
575         }
576
577         /* check and set up bitrates */
578         ieee80211_set_bitrate_flags(wiphy);
579
580         mutex_lock(&cfg80211_mutex);
581
582         res = device_add(&rdev->wiphy.dev);
583         if (res) {
584                 mutex_unlock(&cfg80211_mutex);
585                 return res;
586         }
587
588         /* set up regulatory info */
589         regulatory_update(wiphy, NL80211_REGDOM_SET_BY_CORE);
590
591         list_add_rcu(&rdev->list, &cfg80211_rdev_list);
592         cfg80211_rdev_list_generation++;
593
594         /* add to debugfs */
595         rdev->wiphy.debugfsdir =
596                 debugfs_create_dir(wiphy_name(&rdev->wiphy),
597                                    ieee80211_debugfs_dir);
598         if (IS_ERR(rdev->wiphy.debugfsdir))
599                 rdev->wiphy.debugfsdir = NULL;
600
601         if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
602                 struct regulatory_request request;
603
604                 request.wiphy_idx = get_wiphy_idx(wiphy);
605                 request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
606                 request.alpha2[0] = '9';
607                 request.alpha2[1] = '9';
608
609                 nl80211_send_reg_change_event(&request);
610         }
611
612         cfg80211_debugfs_rdev_add(rdev);
613         mutex_unlock(&cfg80211_mutex);
614
615         /*
616          * due to a locking dependency this has to be outside of the
617          * cfg80211_mutex lock
618          */
619         res = rfkill_register(rdev->rfkill);
620         if (res)
621                 goto out_rm_dev;
622
623         rtnl_lock();
624         rdev->wiphy.registered = true;
625         rtnl_unlock();
626         return 0;
627
628 out_rm_dev:
629         device_del(&rdev->wiphy.dev);
630         return res;
631 }
632 EXPORT_SYMBOL(wiphy_register);
633
634 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
635 {
636         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
637
638         if (!rdev->ops->rfkill_poll)
639                 return;
640         rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
641         rfkill_resume_polling(rdev->rfkill);
642 }
643 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
644
645 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
646 {
647         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
648
649         rfkill_pause_polling(rdev->rfkill);
650 }
651 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
652
653 void wiphy_unregister(struct wiphy *wiphy)
654 {
655         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
656
657         rtnl_lock();
658         rdev->wiphy.registered = false;
659         rtnl_unlock();
660
661         rfkill_unregister(rdev->rfkill);
662
663         /* protect the device list */
664         mutex_lock(&cfg80211_mutex);
665
666         wait_event(rdev->dev_wait, ({
667                 int __count;
668                 mutex_lock(&rdev->devlist_mtx);
669                 __count = rdev->opencount;
670                 mutex_unlock(&rdev->devlist_mtx);
671                 __count == 0;}));
672
673         mutex_lock(&rdev->devlist_mtx);
674         BUG_ON(!list_empty(&rdev->netdev_list));
675         mutex_unlock(&rdev->devlist_mtx);
676
677         /*
678          * First remove the hardware from everywhere, this makes
679          * it impossible to find from userspace.
680          */
681         debugfs_remove_recursive(rdev->wiphy.debugfsdir);
682         list_del_rcu(&rdev->list);
683         synchronize_rcu();
684
685         /*
686          * Try to grab rdev->mtx. If a command is still in progress,
687          * hopefully the driver will refuse it since it's tearing
688          * down the device already. We wait for this command to complete
689          * before unlinking the item from the list.
690          * Note: as codified by the BUG_ON above we cannot get here if
691          * a virtual interface is still present. Hence, we can only get
692          * to lock contention here if userspace issues a command that
693          * identified the hardware by wiphy index.
694          */
695         cfg80211_lock_rdev(rdev);
696         /* nothing */
697         cfg80211_unlock_rdev(rdev);
698
699         /* If this device got a regulatory hint tell core its
700          * free to listen now to a new shiny device regulatory hint */
701         reg_device_remove(wiphy);
702
703         cfg80211_rdev_list_generation++;
704         device_del(&rdev->wiphy.dev);
705
706         mutex_unlock(&cfg80211_mutex);
707
708         flush_work(&rdev->scan_done_wk);
709         cancel_work_sync(&rdev->conn_work);
710         flush_work(&rdev->event_work);
711 }
712 EXPORT_SYMBOL(wiphy_unregister);
713
714 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
715 {
716         struct cfg80211_internal_bss *scan, *tmp;
717         rfkill_destroy(rdev->rfkill);
718         mutex_destroy(&rdev->mtx);
719         mutex_destroy(&rdev->devlist_mtx);
720         mutex_destroy(&rdev->sched_scan_mtx);
721         list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
722                 cfg80211_put_bss(&scan->pub);
723         cfg80211_rdev_free_wowlan(rdev);
724         kfree(rdev);
725 }
726
727 void wiphy_free(struct wiphy *wiphy)
728 {
729         put_device(&wiphy->dev);
730 }
731 EXPORT_SYMBOL(wiphy_free);
732
733 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
734 {
735         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
736
737         if (rfkill_set_hw_state(rdev->rfkill, blocked))
738                 schedule_work(&rdev->rfkill_sync);
739 }
740 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
741
742 static void wdev_cleanup_work(struct work_struct *work)
743 {
744         struct wireless_dev *wdev;
745         struct cfg80211_registered_device *rdev;
746
747         wdev = container_of(work, struct wireless_dev, cleanup_work);
748         rdev = wiphy_to_dev(wdev->wiphy);
749
750         cfg80211_lock_rdev(rdev);
751
752         if (WARN_ON(rdev->scan_req && rdev->scan_req->dev == wdev->netdev)) {
753                 rdev->scan_req->aborted = true;
754                 ___cfg80211_scan_done(rdev, true);
755         }
756
757         cfg80211_unlock_rdev(rdev);
758
759         mutex_lock(&rdev->sched_scan_mtx);
760
761         if (WARN_ON(rdev->sched_scan_req &&
762                     rdev->sched_scan_req->dev == wdev->netdev)) {
763                 __cfg80211_stop_sched_scan(rdev, false);
764         }
765
766         mutex_unlock(&rdev->sched_scan_mtx);
767
768         mutex_lock(&rdev->devlist_mtx);
769         rdev->opencount--;
770         mutex_unlock(&rdev->devlist_mtx);
771         wake_up(&rdev->dev_wait);
772
773         dev_put(wdev->netdev);
774 }
775
776 static struct device_type wiphy_type = {
777         .name   = "wlan",
778 };
779
780 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
781                                          unsigned long state,
782                                          void *ndev)
783 {
784         struct net_device *dev = ndev;
785         struct wireless_dev *wdev = dev->ieee80211_ptr;
786         struct cfg80211_registered_device *rdev;
787         int ret;
788
789         if (!wdev)
790                 return NOTIFY_DONE;
791
792         rdev = wiphy_to_dev(wdev->wiphy);
793
794         WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
795
796         switch (state) {
797         case NETDEV_POST_INIT:
798                 SET_NETDEV_DEVTYPE(dev, &wiphy_type);
799                 break;
800         case NETDEV_REGISTER:
801                 /*
802                  * NB: cannot take rdev->mtx here because this may be
803                  * called within code protected by it when interfaces
804                  * are added with nl80211.
805                  */
806                 mutex_init(&wdev->mtx);
807                 INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
808                 INIT_LIST_HEAD(&wdev->event_list);
809                 spin_lock_init(&wdev->event_lock);
810                 INIT_LIST_HEAD(&wdev->mgmt_registrations);
811                 spin_lock_init(&wdev->mgmt_registrations_lock);
812
813                 mutex_lock(&rdev->devlist_mtx);
814                 list_add_rcu(&wdev->list, &rdev->netdev_list);
815                 rdev->devlist_generation++;
816                 /* can only change netns with wiphy */
817                 dev->features |= NETIF_F_NETNS_LOCAL;
818
819                 if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
820                                       "phy80211")) {
821                         pr_err("failed to add phy80211 symlink to netdev!\n");
822                 }
823                 wdev->netdev = dev;
824                 wdev->sme_state = CFG80211_SME_IDLE;
825                 mutex_unlock(&rdev->devlist_mtx);
826 #ifdef CONFIG_CFG80211_WEXT
827                 wdev->wext.default_key = -1;
828                 wdev->wext.default_mgmt_key = -1;
829                 wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
830 #endif
831
832                 if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
833                         wdev->ps = true;
834                 else
835                         wdev->ps = false;
836                 /* allow mac80211 to determine the timeout */
837                 wdev->ps_timeout = -1;
838
839                 if (!dev->ethtool_ops)
840                         dev->ethtool_ops = &cfg80211_ethtool_ops;
841
842                 if ((wdev->iftype == NL80211_IFTYPE_STATION ||
843                      wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
844                      wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
845                         dev->priv_flags |= IFF_DONT_BRIDGE;
846                 break;
847         case NETDEV_GOING_DOWN:
848                 switch (wdev->iftype) {
849                 case NL80211_IFTYPE_ADHOC:
850                         cfg80211_leave_ibss(rdev, dev, true);
851                         break;
852                 case NL80211_IFTYPE_P2P_CLIENT:
853                 case NL80211_IFTYPE_STATION:
854                         mutex_lock(&rdev->sched_scan_mtx);
855                         __cfg80211_stop_sched_scan(rdev, false);
856                         mutex_unlock(&rdev->sched_scan_mtx);
857
858                         wdev_lock(wdev);
859 #ifdef CONFIG_CFG80211_WEXT
860                         kfree(wdev->wext.ie);
861                         wdev->wext.ie = NULL;
862                         wdev->wext.ie_len = 0;
863                         wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
864 #endif
865                         __cfg80211_disconnect(rdev, dev,
866                                               WLAN_REASON_DEAUTH_LEAVING, true);
867                         cfg80211_mlme_down(rdev, dev);
868                         wdev_unlock(wdev);
869                         break;
870                 case NL80211_IFTYPE_MESH_POINT:
871                         cfg80211_leave_mesh(rdev, dev);
872                         break;
873                 default:
874                         break;
875                 }
876                 wdev->beacon_interval = 0;
877                 break;
878         case NETDEV_DOWN:
879                 dev_hold(dev);
880                 queue_work(cfg80211_wq, &wdev->cleanup_work);
881                 break;
882         case NETDEV_UP:
883                 /*
884                  * If we have a really quick DOWN/UP succession we may
885                  * have this work still pending ... cancel it and see
886                  * if it was pending, in which case we need to account
887                  * for some of the work it would have done.
888                  */
889                 if (cancel_work_sync(&wdev->cleanup_work)) {
890                         mutex_lock(&rdev->devlist_mtx);
891                         rdev->opencount--;
892                         mutex_unlock(&rdev->devlist_mtx);
893                         dev_put(dev);
894                 }
895                 cfg80211_lock_rdev(rdev);
896                 mutex_lock(&rdev->devlist_mtx);
897                 wdev_lock(wdev);
898                 switch (wdev->iftype) {
899 #ifdef CONFIG_CFG80211_WEXT
900                 case NL80211_IFTYPE_ADHOC:
901                         cfg80211_ibss_wext_join(rdev, wdev);
902                         break;
903                 case NL80211_IFTYPE_STATION:
904                         cfg80211_mgd_wext_connect(rdev, wdev);
905                         break;
906 #endif
907 #ifdef CONFIG_MAC80211_MESH
908                 case NL80211_IFTYPE_MESH_POINT:
909                         {
910                                 /* backward compat code... */
911                                 struct mesh_setup setup;
912                                 memcpy(&setup, &default_mesh_setup,
913                                                 sizeof(setup));
914                                  /* back compat only needed for mesh_id */
915                                 setup.mesh_id = wdev->ssid;
916                                 setup.mesh_id_len = wdev->mesh_id_up_len;
917                                 if (wdev->mesh_id_up_len)
918                                         __cfg80211_join_mesh(rdev, dev,
919                                                         &setup,
920                                                         &default_mesh_config);
921                                 break;
922                         }
923 #endif
924                 default:
925                         break;
926                 }
927                 wdev_unlock(wdev);
928                 rdev->opencount++;
929                 mutex_unlock(&rdev->devlist_mtx);
930                 cfg80211_unlock_rdev(rdev);
931
932                 /*
933                  * Configure power management to the driver here so that its
934                  * correctly set also after interface type changes etc.
935                  */
936                 if ((wdev->iftype == NL80211_IFTYPE_STATION ||
937                      wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
938                     rdev->ops->set_power_mgmt)
939                         if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
940                                                       wdev->ps,
941                                                       wdev->ps_timeout)) {
942                                 /* assume this means it's off */
943                                 wdev->ps = false;
944                         }
945                 break;
946         case NETDEV_UNREGISTER:
947                 /*
948                  * NB: cannot take rdev->mtx here because this may be
949                  * called within code protected by it when interfaces
950                  * are removed with nl80211.
951                  */
952                 mutex_lock(&rdev->devlist_mtx);
953                 /*
954                  * It is possible to get NETDEV_UNREGISTER
955                  * multiple times. To detect that, check
956                  * that the interface is still on the list
957                  * of registered interfaces, and only then
958                  * remove and clean it up.
959                  */
960                 if (!list_empty(&wdev->list)) {
961                         sysfs_remove_link(&dev->dev.kobj, "phy80211");
962                         list_del_rcu(&wdev->list);
963                         rdev->devlist_generation++;
964                         cfg80211_mlme_purge_registrations(wdev);
965 #ifdef CONFIG_CFG80211_WEXT
966                         kfree(wdev->wext.keys);
967 #endif
968                 }
969                 mutex_unlock(&rdev->devlist_mtx);
970                 /*
971                  * synchronise (so that we won't find this netdev
972                  * from other code any more) and then clear the list
973                  * head so that the above code can safely check for
974                  * !list_empty() to avoid double-cleanup.
975                  */
976                 synchronize_rcu();
977                 INIT_LIST_HEAD(&wdev->list);
978                 /*
979                  * Ensure that all events have been processed and
980                  * freed.
981                  */
982                 cfg80211_process_wdev_events(wdev);
983                 break;
984         case NETDEV_PRE_UP:
985                 if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
986                         return notifier_from_errno(-EOPNOTSUPP);
987                 if (rfkill_blocked(rdev->rfkill))
988                         return notifier_from_errno(-ERFKILL);
989                 ret = cfg80211_can_add_interface(rdev, wdev->iftype);
990                 if (ret)
991                         return notifier_from_errno(ret);
992                 break;
993         default:
994                 return NOTIFY_DONE;
995         }
996
997         wireless_nlevent_flush();
998
999         return NOTIFY_DONE;
1000 }
1001
1002 static struct notifier_block cfg80211_netdev_notifier = {
1003         .notifier_call = cfg80211_netdev_notifier_call,
1004 };
1005
1006 static void __net_exit cfg80211_pernet_exit(struct net *net)
1007 {
1008         struct cfg80211_registered_device *rdev;
1009
1010         rtnl_lock();
1011         mutex_lock(&cfg80211_mutex);
1012         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1013                 if (net_eq(wiphy_net(&rdev->wiphy), net))
1014                         WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1015         }
1016         mutex_unlock(&cfg80211_mutex);
1017         rtnl_unlock();
1018 }
1019
1020 static struct pernet_operations cfg80211_pernet_ops = {
1021         .exit = cfg80211_pernet_exit,
1022 };
1023
1024 static int __init cfg80211_init(void)
1025 {
1026         int err;
1027
1028         err = register_pernet_device(&cfg80211_pernet_ops);
1029         if (err)
1030                 goto out_fail_pernet;
1031
1032         err = wiphy_sysfs_init();
1033         if (err)
1034                 goto out_fail_sysfs;
1035
1036         err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1037         if (err)
1038                 goto out_fail_notifier;
1039
1040         err = nl80211_init();
1041         if (err)
1042                 goto out_fail_nl80211;
1043
1044         ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1045
1046         err = regulatory_init();
1047         if (err)
1048                 goto out_fail_reg;
1049
1050         cfg80211_wq = create_singlethread_workqueue("cfg80211");
1051         if (!cfg80211_wq)
1052                 goto out_fail_wq;
1053
1054         return 0;
1055
1056 out_fail_wq:
1057         regulatory_exit();
1058 out_fail_reg:
1059         debugfs_remove(ieee80211_debugfs_dir);
1060 out_fail_nl80211:
1061         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1062 out_fail_notifier:
1063         wiphy_sysfs_exit();
1064 out_fail_sysfs:
1065         unregister_pernet_device(&cfg80211_pernet_ops);
1066 out_fail_pernet:
1067         return err;
1068 }
1069 subsys_initcall(cfg80211_init);
1070
1071 static void __exit cfg80211_exit(void)
1072 {
1073         debugfs_remove(ieee80211_debugfs_dir);
1074         nl80211_exit();
1075         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1076         wiphy_sysfs_exit();
1077         regulatory_exit();
1078         unregister_pernet_device(&cfg80211_pernet_ops);
1079         destroy_workqueue(cfg80211_wq);
1080 }
1081 module_exit(cfg80211_exit);