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 struct cfg80211_registered_device *
 100 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
 101 {
 102         struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
 103         struct net_device *dev;
 104
 105         mutex_lock(&cfg80211_mutex);
 106         dev = dev_get_by_index(net, ifindex);
 107         if (!dev)
 108                 goto out;
 109         if (dev->ieee80211_ptr) {
 110                 rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
 111                 mutex_lock(&rdev->mtx);
 112         } else
 113                 rdev = ERR_PTR(-ENODEV);
 114         dev_put(dev);
 115  out:
 116         mutex_unlock(&cfg80211_mutex);
 117         return rdev;
 118 }
 119
 120 /* requires cfg80211_mutex to be held */
 121 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
 122                         char *newname)
 123 {
 124         struct cfg80211_registered_device *rdev2;
 125         int wiphy_idx, taken = -1, result, digits;
 126
 127         assert_cfg80211_lock();
 128
 129         /* prohibit calling the thing phy%d when %d is not its number */
 130         sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
 131         if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
 132                 /* count number of places needed to print wiphy_idx */
 133                 digits = 1;
 134                 while (wiphy_idx /= 10)
 135                         digits++;
 136                 /*
 137                  * deny the name if it is phy<idx> where <idx> is printed
 138                  * without leading zeroes. taken == strlen(newname) here
 139                  */
 140                 if (taken == strlen(PHY_NAME) + digits)
 141                         return -EINVAL;
 142         }
 143
 144
 145         /* Ignore nop renames */
 146         if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
 147                 return 0;
 148
 149         /* Ensure another device does not already have this name. */
 150         list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
 151                 if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
 152                         return -EINVAL;
 153
 154         result = device_rename(&rdev->wiphy.dev, newname);
 155         if (result)
 156                 return result;
 157
 158         if (rdev->wiphy.debugfsdir &&
 159             !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
 160                             rdev->wiphy.debugfsdir,
 161                             rdev->wiphy.debugfsdir->d_parent,
 162                             newname))
 163                 pr_err("failed to rename debugfs dir to %s!\n", newname);
 164
 165         nl80211_notify_dev_rename(rdev);
 166
 167         return 0;
 168 }
 169
 170 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
 171                           struct net *net)
 172 {
 173         struct wireless_dev *wdev;
 174         int err = 0;
 175
 176         if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
 177                 return -EOPNOTSUPP;
 178
 179         list_for_each_entry(wdev, &rdev->wdev_list, list) {
 180                 if (!wdev->netdev)
 181                         continue;
 182                 wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
 183                 err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
 184                 if (err)
 185                         break;
 186                 wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
 187         }
 188
 189         if (err) {
 190                 /* failed -- clean up to old netns */
 191                 net = wiphy_net(&rdev->wiphy);
 192
 193                 list_for_each_entry_continue_reverse(wdev, &rdev->wdev_list,
 194                                                      list) {
 195                         if (!wdev->netdev)
 196                                 continue;
 197                         wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
 198                         err = dev_change_net_namespace(wdev->netdev, net,
 199                                                         "wlan%d");
 200                         WARN_ON(err);
 201                         wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
 202                 }
 203
 204                 return err;
 205         }
 206
 207         wiphy_net_set(&rdev->wiphy, net);
 208
 209         err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
 210         WARN_ON(err);
 211
 212         return 0;
 213 }
 214
 215 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
 216 {
 217         struct cfg80211_registered_device *rdev = data;
 218
 219         rdev->ops->rfkill_poll(&rdev->wiphy);
 220 }
 221
 222 static int cfg80211_rfkill_set_block(void *data, bool blocked)
 223 {
 224         struct cfg80211_registered_device *rdev = data;
 225         struct wireless_dev *wdev;
 226
 227         if (!blocked)
 228                 return 0;
 229
 230         rtnl_lock();
 231         mutex_lock(&rdev->devlist_mtx);
 232
 233         list_for_each_entry(wdev, &rdev->wdev_list, list) {
 234                 if (wdev->netdev) {
 235                         dev_close(wdev->netdev);
 236                         continue;
 237                 }
 238                 /* otherwise, check iftype */
 239                 switch (wdev->iftype) {
 240                 case NL80211_IFTYPE_P2P_DEVICE:
 241                         if (!wdev->p2p_started)
 242                                 break;
 243                         rdev->ops->stop_p2p_device(&rdev->wiphy, wdev);
 244                         wdev->p2p_started = false;
 245                         rdev->opencount--;
 246                         break;
 247                 default:
 248                         break;
 249                 }
 250         }
 251
 252         mutex_unlock(&rdev->devlist_mtx);
 253         rtnl_unlock();
 254
 255         return 0;
 256 }
 257
 258 static void cfg80211_rfkill_sync_work(struct work_struct *work)
 259 {
 260         struct cfg80211_registered_device *rdev;
 261
 262         rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
 263         cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
 264 }
 265
 266 static void cfg80211_event_work(struct work_struct *work)
 267 {
 268         struct cfg80211_registered_device *rdev;
 269
 270         rdev = container_of(work, struct cfg80211_registered_device,
 271                             event_work);
 272
 273         rtnl_lock();
 274         cfg80211_lock_rdev(rdev);
 275
 276         cfg80211_process_rdev_events(rdev);
 277         cfg80211_unlock_rdev(rdev);
 278         rtnl_unlock();
 279 }
 280
 281 /* exported functions */
 282
 283 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
 284 {
 285         static int wiphy_counter;
 286
 287         struct cfg80211_registered_device *rdev;
 288         int alloc_size;
 289
 290         WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
 291         WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
 292         WARN_ON(ops->connect && !ops->disconnect);
 293         WARN_ON(ops->join_ibss && !ops->leave_ibss);
 294         WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
 295         WARN_ON(ops->add_station && !ops->del_station);
 296         WARN_ON(ops->add_mpath && !ops->del_mpath);
 297         WARN_ON(ops->join_mesh && !ops->leave_mesh);
 298
 299         alloc_size = sizeof(*rdev) + sizeof_priv;
 300
 301         rdev = kzalloc(alloc_size, GFP_KERNEL);
 302         if (!rdev)
 303                 return NULL;
 304
 305         rdev->ops = ops;
 306
 307         mutex_lock(&cfg80211_mutex);
 308
 309         rdev->wiphy_idx = wiphy_counter++;
 310
 311         if (unlikely(!wiphy_idx_valid(rdev->wiphy_idx))) {
 312                 wiphy_counter--;
 313                 mutex_unlock(&cfg80211_mutex);
 314                 /* ugh, wrapped! */
 315                 kfree(rdev);
 316                 return NULL;
 317         }
 318
 319         mutex_unlock(&cfg80211_mutex);
 320
 321         /* give it a proper name */
 322         dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
 323
 324         mutex_init(&rdev->mtx);
 325         mutex_init(&rdev->devlist_mtx);
 326         mutex_init(&rdev->sched_scan_mtx);
 327         INIT_LIST_HEAD(&rdev->wdev_list);
 328         spin_lock_init(&rdev->bss_lock);
 329         INIT_LIST_HEAD(&rdev->bss_list);
 330         INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
 331         INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
 332 #ifdef CONFIG_CFG80211_WEXT
 333         rdev->wiphy.wext = &cfg80211_wext_handler;
 334 #endif
 335
 336         device_initialize(&rdev->wiphy.dev);
 337         rdev->wiphy.dev.class = &ieee80211_class;
 338         rdev->wiphy.dev.platform_data = rdev;
 339
 340 #ifdef CONFIG_CFG80211_DEFAULT_PS
 341         rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
 342 #endif
 343
 344         wiphy_net_set(&rdev->wiphy, &init_net);
 345
 346         rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
 347         rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
 348                                    &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
 349                                    &rdev->rfkill_ops, rdev);
 350
 351         if (!rdev->rfkill) {
 352                 kfree(rdev);
 353                 return NULL;
 354         }
 355
 356         INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
 357         INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
 358         INIT_WORK(&rdev->event_work, cfg80211_event_work);
 359
 360         init_waitqueue_head(&rdev->dev_wait);
 361
 362         /*
 363          * Initialize wiphy parameters to IEEE 802.11 MIB default values.
 364          * Fragmentation and RTS threshold are disabled by default with the
 365          * special -1 value.
 366          */
 367         rdev->wiphy.retry_short = 7;
 368         rdev->wiphy.retry_long = 4;
 369         rdev->wiphy.frag_threshold = (u32) -1;
 370         rdev->wiphy.rts_threshold = (u32) -1;
 371         rdev->wiphy.coverage_class = 0;
 372
 373         return &rdev->wiphy;
 374 }
 375 EXPORT_SYMBOL(wiphy_new);
 376
 377 static int wiphy_verify_combinations(struct wiphy *wiphy)
 378 {
 379         const struct ieee80211_iface_combination *c;
 380         int i, j;
 381
 382         for (i = 0; i < wiphy->n_iface_combinations; i++) {
 383                 u32 cnt = 0;
 384                 u16 all_iftypes = 0;
 385
 386                 c = &wiphy->iface_combinations[i];
 387
 388                 /* Combinations with just one interface aren't real */
 389                 if (WARN_ON(c->max_interfaces < 2))
 390                         return -EINVAL;
 391
 392                 /* Need at least one channel */
 393                 if (WARN_ON(!c->num_different_channels))
 394                         return -EINVAL;
 395
 396                 /*
 397                  * Put a sane limit on maximum number of different
 398                  * channels to simplify channel accounting code.
 399                  */
 400                 if (WARN_ON(c->num_different_channels >
 401                                 CFG80211_MAX_NUM_DIFFERENT_CHANNELS))
 402                         return -EINVAL;
 403
 404                 if (WARN_ON(!c->n_limits))
 405                         return -EINVAL;
 406
 407                 for (j = 0; j < c->n_limits; j++) {
 408                         u16 types = c->limits[j].types;
 409
 410                         /*
 411                          * interface types shouldn't overlap, this is
 412                          * used in cfg80211_can_change_interface()
 413                          */
 414                         if (WARN_ON(types & all_iftypes))
 415                                 return -EINVAL;
 416                         all_iftypes |= types;
 417
 418                         if (WARN_ON(!c->limits[j].max))
 419                                 return -EINVAL;
 420
 421                         /* Shouldn't list software iftypes in combinations! */
 422                         if (WARN_ON(wiphy->software_iftypes & types))
 423                                 return -EINVAL;
 424
 425                         /* Only a single P2P_DEVICE can be allowed */
 426                         if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) &&
 427                                     c->limits[j].max > 1))
 428                                 return -EINVAL;
 429
 430                         cnt += c->limits[j].max;
 431                         /*
 432                          * Don't advertise an unsupported type
 433                          * in a combination.
 434                          */
 435                         if (WARN_ON((wiphy->interface_modes & types) != types))
 436                                 return -EINVAL;
 437                 }
 438
 439                 /* You can't even choose that many! */
 440                 if (WARN_ON(cnt < c->max_interfaces))
 441                         return -EINVAL;
 442         }
 443
 444         return 0;
 445 }
 446
 447 int wiphy_register(struct wiphy *wiphy)
 448 {
 449         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 450         int res;
 451         enum ieee80211_band band;
 452         struct ieee80211_supported_band *sband;
 453         bool have_band = false;
 454         int i;
 455         u16 ifmodes = wiphy->interface_modes;
 456
 457 #ifdef CONFIG_PM
 458         if (WARN_ON((wiphy->wowlan.flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
 459                     !(wiphy->wowlan.flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
 460                 return -EINVAL;
 461 #endif
 462
 463         if (WARN_ON(wiphy->ap_sme_capa &&
 464                     !(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME)))
 465                 return -EINVAL;
 466
 467         if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
 468                 return -EINVAL;
 469
 470         if (WARN_ON(wiphy->addresses &&
 471                     !is_zero_ether_addr(wiphy->perm_addr) &&
 472                     memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
 473                            ETH_ALEN)))
 474                 return -EINVAL;
 475
 476         if (wiphy->addresses)
 477                 memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
 478
 479         /* sanity check ifmodes */
 480         WARN_ON(!ifmodes);
 481         ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
 482         if (WARN_ON(ifmodes != wiphy->interface_modes))
 483                 wiphy->interface_modes = ifmodes;
 484
 485         res = wiphy_verify_combinations(wiphy);
 486         if (res)
 487                 return res;
 488
 489         /* sanity check supported bands/channels */
 490         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 491                 sband = wiphy->bands[band];
 492                 if (!sband)
 493                         continue;
 494
 495                 sband->band = band;
 496                 if (WARN_ON(!sband->n_channels))
 497                         return -EINVAL;
 498                 /*
 499                  * on 60gHz band, there are no legacy rates, so
 500                  * n_bitrates is 0
 501                  */
 502                 if (WARN_ON(band != IEEE80211_BAND_60GHZ &&
 503                             !sband->n_bitrates))
 504                         return -EINVAL;
 505
 506                 /*
 507                  * Since cfg80211_disable_40mhz_24ghz is global, we can
 508                  * modify the sband's ht data even if the driver uses a
 509                  * global structure for that.
 510                  */
 511                 if (cfg80211_disable_40mhz_24ghz &&
 512                     band == IEEE80211_BAND_2GHZ &&
 513                     sband->ht_cap.ht_supported) {
 514                         sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 515                         sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
 516                 }
 517
 518                 /*
 519                  * Since we use a u32 for rate bitmaps in
 520                  * ieee80211_get_response_rate, we cannot
 521                  * have more than 32 legacy rates.
 522                  */
 523                 if (WARN_ON(sband->n_bitrates > 32))
 524                         return -EINVAL;
 525
 526                 for (i = 0; i < sband->n_channels; i++) {
 527                         sband->channels[i].orig_flags =
 528                                 sband->channels[i].flags;
 529                         sband->channels[i].orig_mag =
 530                                 sband->channels[i].max_antenna_gain;
 531                         sband->channels[i].orig_mpwr =
 532                                 sband->channels[i].max_power;
 533                         sband->channels[i].band = band;
 534                 }
 535
 536                 have_band = true;
 537         }
 538
 539         if (!have_band) {
 540                 WARN_ON(1);
 541                 return -EINVAL;
 542         }
 543
 544 #ifdef CONFIG_PM
 545         if (rdev->wiphy.wowlan.n_patterns) {
 546                 if (WARN_ON(!rdev->wiphy.wowlan.pattern_min_len ||
 547                             rdev->wiphy.wowlan.pattern_min_len >
 548                             rdev->wiphy.wowlan.pattern_max_len))
 549                         return -EINVAL;
 550         }
 551 #endif
 552
 553         /* check and set up bitrates */
 554         ieee80211_set_bitrate_flags(wiphy);
 555
 556         mutex_lock(&cfg80211_mutex);
 557
 558         res = device_add(&rdev->wiphy.dev);
 559         if (res) {
 560                 mutex_unlock(&cfg80211_mutex);
 561                 return res;
 562         }
 563
 564         /* set up regulatory info */
 565         wiphy_regulatory_register(wiphy);
 566
 567         list_add_rcu(&rdev->list, &cfg80211_rdev_list);
 568         cfg80211_rdev_list_generation++;
 569
 570         /* add to debugfs */
 571         rdev->wiphy.debugfsdir =
 572                 debugfs_create_dir(wiphy_name(&rdev->wiphy),
 573                                    ieee80211_debugfs_dir);
 574         if (IS_ERR(rdev->wiphy.debugfsdir))
 575                 rdev->wiphy.debugfsdir = NULL;
 576
 577         if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
 578                 struct regulatory_request request;
 579
 580                 request.wiphy_idx = get_wiphy_idx(wiphy);
 581                 request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
 582                 request.alpha2[0] = '9';
 583                 request.alpha2[1] = '9';
 584
 585                 nl80211_send_reg_change_event(&request);
 586         }
 587
 588         cfg80211_debugfs_rdev_add(rdev);
 589         mutex_unlock(&cfg80211_mutex);
 590
 591         /*
 592          * due to a locking dependency this has to be outside of the
 593          * cfg80211_mutex lock
 594          */
 595         res = rfkill_register(rdev->rfkill);
 596         if (res)
 597                 goto out_rm_dev;
 598
 599         rtnl_lock();
 600         rdev->wiphy.registered = true;
 601         rtnl_unlock();
 602         return 0;
 603
 604 out_rm_dev:
 605         device_del(&rdev->wiphy.dev);
 606         return res;
 607 }
 608 EXPORT_SYMBOL(wiphy_register);
 609
 610 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
 611 {
 612         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 613
 614         if (!rdev->ops->rfkill_poll)
 615                 return;
 616         rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
 617         rfkill_resume_polling(rdev->rfkill);
 618 }
 619 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
 620
 621 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
 622 {
 623         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 624
 625         rfkill_pause_polling(rdev->rfkill);
 626 }
 627 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
 628
 629 void wiphy_unregister(struct wiphy *wiphy)
 630 {
 631         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 632
 633         rtnl_lock();
 634         rdev->wiphy.registered = false;
 635         rtnl_unlock();
 636
 637         rfkill_unregister(rdev->rfkill);
 638
 639         /* protect the device list */
 640         mutex_lock(&cfg80211_mutex);
 641
 642         wait_event(rdev->dev_wait, ({
 643                 int __count;
 644                 mutex_lock(&rdev->devlist_mtx);
 645                 __count = rdev->opencount;
 646                 mutex_unlock(&rdev->devlist_mtx);
 647                 __count == 0; }));
 648
 649         mutex_lock(&rdev->devlist_mtx);
 650         BUG_ON(!list_empty(&rdev->wdev_list));
 651         mutex_unlock(&rdev->devlist_mtx);
 652
 653         /*
 654          * First remove the hardware from everywhere, this makes
 655          * it impossible to find from userspace.
 656          */
 657         debugfs_remove_recursive(rdev->wiphy.debugfsdir);
 658         list_del_rcu(&rdev->list);
 659         synchronize_rcu();
 660
 661         /*
 662          * Try to grab rdev->mtx. If a command is still in progress,
 663          * hopefully the driver will refuse it since it's tearing
 664          * down the device already. We wait for this command to complete
 665          * before unlinking the item from the list.
 666          * Note: as codified by the BUG_ON above we cannot get here if
 667          * a virtual interface is still present. Hence, we can only get
 668          * to lock contention here if userspace issues a command that
 669          * identified the hardware by wiphy index.
 670          */
 671         cfg80211_lock_rdev(rdev);
 672         /* nothing */
 673         cfg80211_unlock_rdev(rdev);
 674
 675         /*
 676          * If this device got a regulatory hint tell core its
 677          * free to listen now to a new shiny device regulatory hint
 678          */
 679         wiphy_regulatory_deregister(wiphy);
 680
 681         cfg80211_rdev_list_generation++;
 682         device_del(&rdev->wiphy.dev);
 683
 684         mutex_unlock(&cfg80211_mutex);
 685
 686         flush_work(&rdev->scan_done_wk);
 687         cancel_work_sync(&rdev->conn_work);
 688         flush_work(&rdev->event_work);
 689
 690         if (rdev->wowlan && rdev->ops->set_wakeup)
 691                 rdev->ops->set_wakeup(&rdev->wiphy, false);
 692         cfg80211_rdev_free_wowlan(rdev);
 693 }
 694 EXPORT_SYMBOL(wiphy_unregister);
 695
 696 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
 697 {
 698         struct cfg80211_internal_bss *scan, *tmp;
 699         rfkill_destroy(rdev->rfkill);
 700         mutex_destroy(&rdev->mtx);
 701         mutex_destroy(&rdev->devlist_mtx);
 702         mutex_destroy(&rdev->sched_scan_mtx);
 703         list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
 704                 cfg80211_put_bss(&scan->pub);
 705         kfree(rdev);
 706 }
 707
 708 void wiphy_free(struct wiphy *wiphy)
 709 {
 710         put_device(&wiphy->dev);
 711 }
 712 EXPORT_SYMBOL(wiphy_free);
 713
 714 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
 715 {
 716         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 717
 718         if (rfkill_set_hw_state(rdev->rfkill, blocked))
 719                 schedule_work(&rdev->rfkill_sync);
 720 }
 721 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
 722
 723 static void wdev_cleanup_work(struct work_struct *work)
 724 {
 725         struct wireless_dev *wdev;
 726         struct cfg80211_registered_device *rdev;
 727
 728         wdev = container_of(work, struct wireless_dev, cleanup_work);
 729         rdev = wiphy_to_dev(wdev->wiphy);
 730
 731         cfg80211_lock_rdev(rdev);
 732
 733         if (WARN_ON(rdev->scan_req && rdev->scan_req->wdev == wdev)) {
 734                 rdev->scan_req->aborted = true;
 735                 ___cfg80211_scan_done(rdev, true);
 736         }
 737
 738         cfg80211_unlock_rdev(rdev);
 739
 740         mutex_lock(&rdev->sched_scan_mtx);
 741
 742         if (WARN_ON(rdev->sched_scan_req &&
 743                     rdev->sched_scan_req->dev == wdev->netdev)) {
 744                 __cfg80211_stop_sched_scan(rdev, false);
 745         }
 746
 747         mutex_unlock(&rdev->sched_scan_mtx);
 748
 749         mutex_lock(&rdev->devlist_mtx);
 750         rdev->opencount--;
 751         mutex_unlock(&rdev->devlist_mtx);
 752         wake_up(&rdev->dev_wait);
 753
 754         dev_put(wdev->netdev);
 755 }
 756
 757 void cfg80211_unregister_wdev(struct wireless_dev *wdev)
 758 {
 759         struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
 760
 761         ASSERT_RTNL();
 762
 763         if (WARN_ON(wdev->netdev))
 764                 return;
 765
 766         mutex_lock(&rdev->devlist_mtx);
 767         list_del_rcu(&wdev->list);
 768         rdev->devlist_generation++;
 769
 770         switch (wdev->iftype) {
 771         case NL80211_IFTYPE_P2P_DEVICE:
 772                 if (!wdev->p2p_started)
 773                         break;
 774                 rdev->ops->stop_p2p_device(&rdev->wiphy, wdev);
 775                 wdev->p2p_started = false;
 776                 rdev->opencount--;
 777                 break;
 778         default:
 779                 WARN_ON_ONCE(1);
 780                 break;
 781         }
 782         mutex_unlock(&rdev->devlist_mtx);
 783 }
 784 EXPORT_SYMBOL(cfg80211_unregister_wdev);
 785
 786 static struct device_type wiphy_type = {
 787         .name   = "wlan",
 788 };
 789
 790 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
 791                                enum nl80211_iftype iftype, int num)
 792 {
 793         ASSERT_RTNL();
 794
 795         rdev->num_running_ifaces += num;
 796         if (iftype == NL80211_IFTYPE_MONITOR)
 797                 rdev->num_running_monitor_ifaces += num;
 798 }
 799
 800 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
 801                                          unsigned long state,
 802                                          void *ndev)
 803 {
 804         struct net_device *dev = ndev;
 805         struct wireless_dev *wdev = dev->ieee80211_ptr;
 806         struct cfg80211_registered_device *rdev;
 807         int ret;
 808
 809         if (!wdev)
 810                 return NOTIFY_DONE;
 811
 812         rdev = wiphy_to_dev(wdev->wiphy);
 813
 814         WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
 815
 816         switch (state) {
 817         case NETDEV_POST_INIT:
 818                 SET_NETDEV_DEVTYPE(dev, &wiphy_type);
 819                 break;
 820         case NETDEV_REGISTER:
 821                 /*
 822                  * NB: cannot take rdev->mtx here because this may be
 823                  * called within code protected by it when interfaces
 824                  * are added with nl80211.
 825                  */
 826                 mutex_init(&wdev->mtx);
 827                 INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
 828                 INIT_LIST_HEAD(&wdev->event_list);
 829                 spin_lock_init(&wdev->event_lock);
 830                 INIT_LIST_HEAD(&wdev->mgmt_registrations);
 831                 spin_lock_init(&wdev->mgmt_registrations_lock);
 832
 833                 mutex_lock(&rdev->devlist_mtx);
 834                 wdev->identifier = ++rdev->wdev_id;
 835                 list_add_rcu(&wdev->list, &rdev->wdev_list);
 836                 rdev->devlist_generation++;
 837                 /* can only change netns with wiphy */
 838                 dev->features |= NETIF_F_NETNS_LOCAL;
 839
 840                 if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
 841                                       "phy80211")) {
 842                         pr_err("failed to add phy80211 symlink to netdev!\n");
 843                 }
 844                 wdev->netdev = dev;
 845                 wdev->sme_state = CFG80211_SME_IDLE;
 846                 mutex_unlock(&rdev->devlist_mtx);
 847 #ifdef CONFIG_CFG80211_WEXT
 848                 wdev->wext.default_key = -1;
 849                 wdev->wext.default_mgmt_key = -1;
 850                 wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
 851 #endif
 852
 853                 if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
 854                         wdev->ps = true;
 855                 else
 856                         wdev->ps = false;
 857                 /* allow mac80211 to determine the timeout */
 858                 wdev->ps_timeout = -1;
 859
 860                 if (!dev->ethtool_ops)
 861                         dev->ethtool_ops = &cfg80211_ethtool_ops;
 862
 863                 if ((wdev->iftype == NL80211_IFTYPE_STATION ||
 864                      wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
 865                      wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
 866                         dev->priv_flags |= IFF_DONT_BRIDGE;
 867                 break;
 868         case NETDEV_GOING_DOWN:
 869                 switch (wdev->iftype) {
 870                 case NL80211_IFTYPE_ADHOC:
 871                         cfg80211_leave_ibss(rdev, dev, true);
 872                         break;
 873                 case NL80211_IFTYPE_P2P_CLIENT:
 874                 case NL80211_IFTYPE_STATION:
 875                         mutex_lock(&rdev->sched_scan_mtx);
 876                         __cfg80211_stop_sched_scan(rdev, false);
 877                         mutex_unlock(&rdev->sched_scan_mtx);
 878
 879                         wdev_lock(wdev);
 880 #ifdef CONFIG_CFG80211_WEXT
 881                         kfree(wdev->wext.ie);
 882                         wdev->wext.ie = NULL;
 883                         wdev->wext.ie_len = 0;
 884                         wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
 885 #endif
 886                         __cfg80211_disconnect(rdev, dev,
 887                                               WLAN_REASON_DEAUTH_LEAVING, true);
 888                         cfg80211_mlme_down(rdev, dev);
 889                         wdev_unlock(wdev);
 890                         break;
 891                 case NL80211_IFTYPE_MESH_POINT:
 892                         cfg80211_leave_mesh(rdev, dev);
 893                         break;
 894                 case NL80211_IFTYPE_AP:
 895                         cfg80211_stop_ap(rdev, dev);
 896                         break;
 897                 default:
 898                         break;
 899                 }
 900                 wdev->beacon_interval = 0;
 901                 break;
 902         case NETDEV_DOWN:
 903                 cfg80211_update_iface_num(rdev, wdev->iftype, -1);
 904                 dev_hold(dev);
 905                 queue_work(cfg80211_wq, &wdev->cleanup_work);
 906                 break;
 907         case NETDEV_UP:
 908                 /*
 909                  * If we have a really quick DOWN/UP succession we may
 910                  * have this work still pending ... cancel it and see
 911                  * if it was pending, in which case we need to account
 912                  * for some of the work it would have done.
 913                  */
 914                 if (cancel_work_sync(&wdev->cleanup_work)) {
 915                         mutex_lock(&rdev->devlist_mtx);
 916                         rdev->opencount--;
 917                         mutex_unlock(&rdev->devlist_mtx);
 918                         dev_put(dev);
 919                 }
 920                 cfg80211_update_iface_num(rdev, wdev->iftype, 1);
 921                 cfg80211_lock_rdev(rdev);
 922                 mutex_lock(&rdev->devlist_mtx);
 923                 wdev_lock(wdev);
 924                 switch (wdev->iftype) {
 925 #ifdef CONFIG_CFG80211_WEXT
 926                 case NL80211_IFTYPE_ADHOC:
 927                         cfg80211_ibss_wext_join(rdev, wdev);
 928                         break;
 929                 case NL80211_IFTYPE_STATION:
 930                         cfg80211_mgd_wext_connect(rdev, wdev);
 931                         break;
 932 #endif
 933 #ifdef CONFIG_MAC80211_MESH
 934                 case NL80211_IFTYPE_MESH_POINT:
 935                         {
 936                                 /* backward compat code... */
 937                                 struct mesh_setup setup;
 938                                 memcpy(&setup, &default_mesh_setup,
 939                                                 sizeof(setup));
 940                                  /* back compat only needed for mesh_id */
 941                                 setup.mesh_id = wdev->ssid;
 942                                 setup.mesh_id_len = wdev->mesh_id_up_len;
 943                                 if (wdev->mesh_id_up_len)
 944                                         __cfg80211_join_mesh(rdev, dev,
 945                                                         &setup,
 946                                                         &default_mesh_config);
 947                                 break;
 948                         }
 949 #endif
 950                 default:
 951                         break;
 952                 }
 953                 wdev_unlock(wdev);
 954                 rdev->opencount++;
 955                 mutex_unlock(&rdev->devlist_mtx);
 956                 cfg80211_unlock_rdev(rdev);
 957
 958                 /*
 959                  * Configure power management to the driver here so that its
 960                  * correctly set also after interface type changes etc.
 961                  */
 962                 if ((wdev->iftype == NL80211_IFTYPE_STATION ||
 963                      wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
 964                     rdev->ops->set_power_mgmt)
 965                         if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
 966                                                       wdev->ps,
 967                                                       wdev->ps_timeout)) {
 968                                 /* assume this means it's off */
 969                                 wdev->ps = false;
 970                         }
 971                 break;
 972         case NETDEV_UNREGISTER:
 973                 /*
 974                  * NB: cannot take rdev->mtx here because this may be
 975                  * called within code protected by it when interfaces
 976                  * are removed with nl80211.
 977                  */
 978                 mutex_lock(&rdev->devlist_mtx);
 979                 /*
 980                  * It is possible to get NETDEV_UNREGISTER
 981                  * multiple times. To detect that, check
 982                  * that the interface is still on the list
 983                  * of registered interfaces, and only then
 984                  * remove and clean it up.
 985                  */
 986                 if (!list_empty(&wdev->list)) {
 987                         sysfs_remove_link(&dev->dev.kobj, "phy80211");
 988                         list_del_rcu(&wdev->list);
 989                         rdev->devlist_generation++;
 990                         cfg80211_mlme_purge_registrations(wdev);
 991 #ifdef CONFIG_CFG80211_WEXT
 992                         kfree(wdev->wext.keys);
 993 #endif
 994                 }
 995                 mutex_unlock(&rdev->devlist_mtx);
 996                 /*
 997                  * synchronise (so that we won't find this netdev
 998                  * from other code any more) and then clear the list
 999                  * head so that the above code can safely check for
1000                  * !list_empty() to avoid double-cleanup.
1001                  */
1002                 synchronize_rcu();
1003                 INIT_LIST_HEAD(&wdev->list);
1004                 /*
1005                  * Ensure that all events have been processed and
1006                  * freed.
1007                  */
1008                 cfg80211_process_wdev_events(wdev);
1009                 break;
1010         case NETDEV_PRE_UP:
1011                 if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
1012                         return notifier_from_errno(-EOPNOTSUPP);
1013                 if (rfkill_blocked(rdev->rfkill))
1014                         return notifier_from_errno(-ERFKILL);
1015                 mutex_lock(&rdev->devlist_mtx);
1016                 ret = cfg80211_can_add_interface(rdev, wdev->iftype);
1017                 mutex_unlock(&rdev->devlist_mtx);
1018                 if (ret)
1019                         return notifier_from_errno(ret);
1020                 break;
1021         }
1022
1023         return NOTIFY_DONE;
1024 }
1025
1026 static struct notifier_block cfg80211_netdev_notifier = {
1027         .notifier_call = cfg80211_netdev_notifier_call,
1028 };
1029
1030 static void __net_exit cfg80211_pernet_exit(struct net *net)
1031 {
1032         struct cfg80211_registered_device *rdev;
1033
1034         rtnl_lock();
1035         mutex_lock(&cfg80211_mutex);
1036         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1037                 if (net_eq(wiphy_net(&rdev->wiphy), net))
1038                         WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1039         }
1040         mutex_unlock(&cfg80211_mutex);
1041         rtnl_unlock();
1042 }
1043
1044 static struct pernet_operations cfg80211_pernet_ops = {
1045         .exit = cfg80211_pernet_exit,
1046 };
1047
1048 static int __init cfg80211_init(void)
1049 {
1050         int err;
1051
1052         err = register_pernet_device(&cfg80211_pernet_ops);
1053         if (err)
1054                 goto out_fail_pernet;
1055
1056         err = wiphy_sysfs_init();
1057         if (err)
1058                 goto out_fail_sysfs;
1059
1060         err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1061         if (err)
1062                 goto out_fail_notifier;
1063
1064         err = nl80211_init();
1065         if (err)
1066                 goto out_fail_nl80211;
1067
1068         ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1069
1070         err = regulatory_init();
1071         if (err)
1072                 goto out_fail_reg;
1073
1074         cfg80211_wq = create_singlethread_workqueue("cfg80211");
1075         if (!cfg80211_wq)
1076                 goto out_fail_wq;
1077
1078         return 0;
1079
1080 out_fail_wq:
1081         regulatory_exit();
1082 out_fail_reg:
1083         debugfs_remove(ieee80211_debugfs_dir);
1084 out_fail_nl80211:
1085         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1086 out_fail_notifier:
1087         wiphy_sysfs_exit();
1088 out_fail_sysfs:
1089         unregister_pernet_device(&cfg80211_pernet_ops);
1090 out_fail_pernet:
1091         return err;
1092 }
1093 subsys_initcall(cfg80211_init);
1094
1095 static void __exit cfg80211_exit(void)
1096 {
1097         debugfs_remove(ieee80211_debugfs_dir);
1098         nl80211_exit();
1099         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1100         wiphy_sysfs_exit();
1101         regulatory_exit();
1102         unregister_pernet_device(&cfg80211_pernet_ops);
1103         destroy_workqueue(cfg80211_wq);
1104 }
1105 module_exit(cfg80211_exit);