net/mac80211/scan.c

   1 /*
   2  * Scanning implementation
   3  *
   4  * Copyright 2003, Jouni Malinen <[email protected]>
   5  * Copyright 2004, Instant802 Networks, Inc.
   6  * Copyright 2005, Devicescape Software, Inc.
   7  * Copyright 2006-2007  Jiri Benc <[email protected]>
   8  * Copyright 2007, Michael Wu <[email protected]>
   9  * Copyright 2013-2015  Intel Mobile Communications GmbH
  10  * Copyright 2016-2017  Intel Deutschland GmbH
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/if_arp.h>
  18 #include <linux/etherdevice.h>
  19 #include <linux/rtnetlink.h>
  20 #include <net/sch_generic.h>
  21 #include <linux/slab.h>
  22 #include <linux/export.h>
  23 #include <net/mac80211.h>
  24
  25 #include "ieee80211_i.h"
  26 #include "driver-ops.h"
  27 #include "mesh.h"
  28
  29 #define IEEE80211_PROBE_DELAY (HZ / 33)
  30 #define IEEE80211_CHANNEL_TIME (HZ / 33)
  31 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
  32
  33 void ieee80211_rx_bss_put(struct ieee80211_local *local,
  34                           struct ieee80211_bss *bss)
  35 {
  36         if (!bss)
  37                 return;
  38         cfg80211_put_bss(local->hw.wiphy,
  39                          container_of((void *)bss, struct cfg80211_bss, priv));
  40 }
  41
  42 static bool is_uapsd_supported(struct ieee802_11_elems *elems)
  43 {
  44         u8 qos_info;
  45
  46         if (elems->wmm_info && elems->wmm_info_len == 7
  47             && elems->wmm_info[5] == 1)
  48                 qos_info = elems->wmm_info[6];
  49         else if (elems->wmm_param && elems->wmm_param_len == 24
  50                  && elems->wmm_param[5] == 1)
  51                 qos_info = elems->wmm_param[6];
  52         else
  53                 /* no valid wmm information or parameter element found */
  54                 return false;
  55
  56         return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
  57 }
  58
  59 struct ieee80211_bss *
  60 ieee80211_bss_info_update(struct ieee80211_local *local,
  61                           struct ieee80211_rx_status *rx_status,
  62                           struct ieee80211_mgmt *mgmt, size_t len,
  63                           struct ieee802_11_elems *elems,
  64                           struct ieee80211_channel *channel)
  65 {
  66         bool beacon = ieee80211_is_beacon(mgmt->frame_control);
  67         struct cfg80211_bss *cbss;
  68         struct ieee80211_bss *bss;
  69         int clen, srlen;
  70         struct cfg80211_inform_bss bss_meta = {
  71                 .boottime_ns = rx_status->boottime_ns,
  72         };
  73         bool signal_valid;
  74         struct ieee80211_sub_if_data *scan_sdata;
  75
  76         if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
  77                 bss_meta.signal = rx_status->signal * 100;
  78         else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
  79                 bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
  80
  81         bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20;
  82         if (rx_status->bw == RATE_INFO_BW_5)
  83                 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5;
  84         else if (rx_status->bw == RATE_INFO_BW_10)
  85                 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10;
  86
  87         bss_meta.chan = channel;
  88
  89         rcu_read_lock();
  90         scan_sdata = rcu_dereference(local->scan_sdata);
  91         if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
  92             scan_sdata->vif.bss_conf.assoc &&
  93             ieee80211_have_rx_timestamp(rx_status)) {
  94                 bss_meta.parent_tsf =
  95                         ieee80211_calculate_rx_timestamp(local, rx_status,
  96                                                          len + FCS_LEN, 24);
  97                 ether_addr_copy(bss_meta.parent_bssid,
  98                                 scan_sdata->vif.bss_conf.bssid);
  99         }
 100         rcu_read_unlock();
 101
 102         cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
 103                                               mgmt, len, GFP_ATOMIC);
 104         if (!cbss)
 105                 return NULL;
 106         /* In case the signal is invalid update the status */
 107         signal_valid = abs(channel->center_freq - cbss->channel->center_freq)
 108                 <= local->hw.wiphy->max_adj_channel_rssi_comp;
 109         if (!signal_valid)
 110                 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
 111
 112         bss = (void *)cbss->priv;
 113
 114         if (beacon)
 115                 bss->device_ts_beacon = rx_status->device_timestamp;
 116         else
 117                 bss->device_ts_presp = rx_status->device_timestamp;
 118
 119         if (elems->parse_error) {
 120                 if (beacon)
 121                         bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
 122                 else
 123                         bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
 124         } else {
 125                 if (beacon)
 126                         bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
 127                 else
 128                         bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
 129         }
 130
 131         /* save the ERP value so that it is available at association time */
 132         if (elems->erp_info && (!elems->parse_error ||
 133                                 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
 134                 bss->erp_value = elems->erp_info[0];
 135                 bss->has_erp_value = true;
 136                 if (!elems->parse_error)
 137                         bss->valid_data |= IEEE80211_BSS_VALID_ERP;
 138         }
 139
 140         /* replace old supported rates if we get new values */
 141         if (!elems->parse_error ||
 142             !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
 143                 srlen = 0;
 144                 if (elems->supp_rates) {
 145                         clen = IEEE80211_MAX_SUPP_RATES;
 146                         if (clen > elems->supp_rates_len)
 147                                 clen = elems->supp_rates_len;
 148                         memcpy(bss->supp_rates, elems->supp_rates, clen);
 149                         srlen += clen;
 150                 }
 151                 if (elems->ext_supp_rates) {
 152                         clen = IEEE80211_MAX_SUPP_RATES - srlen;
 153                         if (clen > elems->ext_supp_rates_len)
 154                                 clen = elems->ext_supp_rates_len;
 155                         memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
 156                                clen);
 157                         srlen += clen;
 158                 }
 159                 if (srlen) {
 160                         bss->supp_rates_len = srlen;
 161                         if (!elems->parse_error)
 162                                 bss->valid_data |= IEEE80211_BSS_VALID_RATES;
 163                 }
 164         }
 165
 166         if (!elems->parse_error ||
 167             !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
 168                 bss->wmm_used = elems->wmm_param || elems->wmm_info;
 169                 bss->uapsd_supported = is_uapsd_supported(elems);
 170                 if (!elems->parse_error)
 171                         bss->valid_data |= IEEE80211_BSS_VALID_WMM;
 172         }
 173
 174         if (beacon) {
 175                 struct ieee80211_supported_band *sband =
 176                         local->hw.wiphy->bands[rx_status->band];
 177                 if (!(rx_status->encoding == RX_ENC_HT) &&
 178                     !(rx_status->encoding == RX_ENC_VHT))
 179                         bss->beacon_rate =
 180                                 &sband->bitrates[rx_status->rate_idx];
 181         }
 182
 183         return bss;
 184 }
 185
 186 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
 187                                         u32 scan_flags, const u8 *da)
 188 {
 189         if (!sdata)
 190                 return false;
 191         /* accept broadcast for OCE */
 192         if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
 193             is_broadcast_ether_addr(da))
 194                 return true;
 195         if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 196                 return true;
 197         return ether_addr_equal(da, sdata->vif.addr);
 198 }
 199
 200 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
 201 {
 202         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
 203         struct ieee80211_sub_if_data *sdata1, *sdata2;
 204         struct ieee80211_mgmt *mgmt = (void *)skb->data;
 205         struct ieee80211_bss *bss;
 206         u8 *elements;
 207         struct ieee80211_channel *channel;
 208         size_t baselen;
 209         struct ieee802_11_elems elems;
 210
 211         if (skb->len < 24 ||
 212             (!ieee80211_is_probe_resp(mgmt->frame_control) &&
 213              !ieee80211_is_beacon(mgmt->frame_control)))
 214                 return;
 215
 216         sdata1 = rcu_dereference(local->scan_sdata);
 217         sdata2 = rcu_dereference(local->sched_scan_sdata);
 218
 219         if (likely(!sdata1 && !sdata2))
 220                 return;
 221
 222         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 223                 struct cfg80211_scan_request *scan_req;
 224                 struct cfg80211_sched_scan_request *sched_scan_req;
 225                 u32 scan_req_flags = 0, sched_scan_req_flags = 0;
 226
 227                 scan_req = rcu_dereference(local->scan_req);
 228                 sched_scan_req = rcu_dereference(local->sched_scan_req);
 229
 230                 if (scan_req)
 231                         scan_req_flags = scan_req->flags;
 232
 233                 if (sched_scan_req)
 234                         sched_scan_req_flags = sched_scan_req->flags;
 235
 236                 /* ignore ProbeResp to foreign address or non-bcast (OCE)
 237                  * unless scanning with randomised address
 238                  */
 239                 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
 240                                                  mgmt->da) &&
 241                     !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
 242                                                  mgmt->da))
 243                         return;
 244
 245                 elements = mgmt->u.probe_resp.variable;
 246                 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
 247         } else {
 248                 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
 249                 elements = mgmt->u.beacon.variable;
 250         }
 251
 252         if (baselen > skb->len)
 253                 return;
 254
 255         ieee802_11_parse_elems(elements, skb->len - baselen, false, &elems);
 256
 257         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
 258
 259         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 260                 return;
 261
 262         bss = ieee80211_bss_info_update(local, rx_status,
 263                                         mgmt, skb->len, &elems,
 264                                         channel);
 265         if (bss)
 266                 ieee80211_rx_bss_put(local, bss);
 267 }
 268
 269 static void
 270 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
 271                                enum nl80211_bss_scan_width scan_width)
 272 {
 273         memset(chandef, 0, sizeof(*chandef));
 274         switch (scan_width) {
 275         case NL80211_BSS_CHAN_WIDTH_5:
 276                 chandef->width = NL80211_CHAN_WIDTH_5;
 277                 break;
 278         case NL80211_BSS_CHAN_WIDTH_10:
 279                 chandef->width = NL80211_CHAN_WIDTH_10;
 280                 break;
 281         default:
 282                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 283                 break;
 284         }
 285 }
 286
 287 /* return false if no more work */
 288 static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
 289 {
 290         struct cfg80211_scan_request *req;
 291         struct cfg80211_chan_def chandef;
 292         u8 bands_used = 0;
 293         int i, ielen, n_chans;
 294
 295         req = rcu_dereference_protected(local->scan_req,
 296                                         lockdep_is_held(&local->mtx));
 297
 298         if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
 299                 return false;
 300
 301         if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 302                 for (i = 0; i < req->n_channels; i++) {
 303                         local->hw_scan_req->req.channels[i] = req->channels[i];
 304                         bands_used |= BIT(req->channels[i]->band);
 305                 }
 306
 307                 n_chans = req->n_channels;
 308         } else {
 309                 do {
 310                         if (local->hw_scan_band == NUM_NL80211_BANDS)
 311                                 return false;
 312
 313                         n_chans = 0;
 314
 315                         for (i = 0; i < req->n_channels; i++) {
 316                                 if (req->channels[i]->band !=
 317                                     local->hw_scan_band)
 318                                         continue;
 319                                 local->hw_scan_req->req.channels[n_chans] =
 320                                                         req->channels[i];
 321                                 n_chans++;
 322                                 bands_used |= BIT(req->channels[i]->band);
 323                         }
 324
 325                         local->hw_scan_band++;
 326                 } while (!n_chans);
 327         }
 328
 329         local->hw_scan_req->req.n_channels = n_chans;
 330         ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
 331
 332         ielen = ieee80211_build_preq_ies(local,
 333                                          (u8 *)local->hw_scan_req->req.ie,
 334                                          local->hw_scan_ies_bufsize,
 335                                          &local->hw_scan_req->ies,
 336                                          req->ie, req->ie_len,
 337                                          bands_used, req->rates, &chandef);
 338         local->hw_scan_req->req.ie_len = ielen;
 339         local->hw_scan_req->req.no_cck = req->no_cck;
 340         ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
 341         ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
 342                         req->mac_addr_mask);
 343         ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
 344
 345         return true;
 346 }
 347
 348 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 349 {
 350         struct ieee80211_local *local = hw_to_local(hw);
 351         bool hw_scan = local->ops->hw_scan;
 352         bool was_scanning = local->scanning;
 353         struct cfg80211_scan_request *scan_req;
 354         struct ieee80211_sub_if_data *scan_sdata;
 355         struct ieee80211_sub_if_data *sdata;
 356
 357         lockdep_assert_held(&local->mtx);
 358
 359         /*
 360          * It's ok to abort a not-yet-running scan (that
 361          * we have one at all will be verified by checking
 362          * local->scan_req next), but not to complete it
 363          * successfully.
 364          */
 365         if (WARN_ON(!local->scanning && !aborted))
 366                 aborted = true;
 367
 368         if (WARN_ON(!local->scan_req))
 369                 return;
 370
 371         if (hw_scan && !aborted &&
 372             !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
 373             ieee80211_prep_hw_scan(local)) {
 374                 int rc;
 375
 376                 rc = drv_hw_scan(local,
 377                         rcu_dereference_protected(local->scan_sdata,
 378                                                   lockdep_is_held(&local->mtx)),
 379                         local->hw_scan_req);
 380
 381                 if (rc == 0)
 382                         return;
 383
 384                 /* HW scan failed and is going to be reported as aborted,
 385                  * so clear old scan info.
 386                  */
 387                 memset(&local->scan_info, 0, sizeof(local->scan_info));
 388                 aborted = true;
 389         }
 390
 391         kfree(local->hw_scan_req);
 392         local->hw_scan_req = NULL;
 393
 394         scan_req = rcu_dereference_protected(local->scan_req,
 395                                              lockdep_is_held(&local->mtx));
 396
 397         if (scan_req != local->int_scan_req) {
 398                 local->scan_info.aborted = aborted;
 399                 cfg80211_scan_done(scan_req, &local->scan_info);
 400         }
 401         RCU_INIT_POINTER(local->scan_req, NULL);
 402
 403         scan_sdata = rcu_dereference_protected(local->scan_sdata,
 404                                                lockdep_is_held(&local->mtx));
 405         RCU_INIT_POINTER(local->scan_sdata, NULL);
 406
 407         local->scanning = 0;
 408         local->scan_chandef.chan = NULL;
 409
 410         /* Set power back to normal operating levels. */
 411         ieee80211_hw_config(local, 0);
 412
 413         if (!hw_scan) {
 414                 ieee80211_configure_filter(local);
 415                 drv_sw_scan_complete(local, scan_sdata);
 416                 ieee80211_offchannel_return(local);
 417         }
 418
 419         ieee80211_recalc_idle(local);
 420
 421         ieee80211_mlme_notify_scan_completed(local);
 422         ieee80211_ibss_notify_scan_completed(local);
 423
 424         /* Requeue all the work that might have been ignored while
 425          * the scan was in progress; if there was none this will
 426          * just be a no-op for the particular interface.
 427          */
 428         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 429                 if (ieee80211_sdata_running(sdata))
 430                         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 431         }
 432
 433         if (was_scanning)
 434                 ieee80211_start_next_roc(local);
 435 }
 436
 437 void ieee80211_scan_completed(struct ieee80211_hw *hw,
 438                               struct cfg80211_scan_info *info)
 439 {
 440         struct ieee80211_local *local = hw_to_local(hw);
 441
 442         trace_api_scan_completed(local, info->aborted);
 443
 444         set_bit(SCAN_COMPLETED, &local->scanning);
 445         if (info->aborted)
 446                 set_bit(SCAN_ABORTED, &local->scanning);
 447
 448         memcpy(&local->scan_info, info, sizeof(*info));
 449
 450         ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
 451 }
 452 EXPORT_SYMBOL(ieee80211_scan_completed);
 453
 454 static int ieee80211_start_sw_scan(struct ieee80211_local *local,
 455                                    struct ieee80211_sub_if_data *sdata)
 456 {
 457         /* Software scan is not supported in multi-channel cases */
 458         if (local->use_chanctx)
 459                 return -EOPNOTSUPP;
 460
 461         /*
 462          * Hardware/driver doesn't support hw_scan, so use software
 463          * scanning instead. First send a nullfunc frame with power save
 464          * bit on so that AP will buffer the frames for us while we are not
 465          * listening, then send probe requests to each channel and wait for
 466          * the responses. After all channels are scanned, tune back to the
 467          * original channel and send a nullfunc frame with power save bit
 468          * off to trigger the AP to send us all the buffered frames.
 469          *
 470          * Note that while local->sw_scanning is true everything else but
 471          * nullfunc frames and probe requests will be dropped in
 472          * ieee80211_tx_h_check_assoc().
 473          */
 474         drv_sw_scan_start(local, sdata, local->scan_addr);
 475
 476         local->leave_oper_channel_time = jiffies;
 477         local->next_scan_state = SCAN_DECISION;
 478         local->scan_channel_idx = 0;
 479
 480         ieee80211_offchannel_stop_vifs(local);
 481
 482         /* ensure nullfunc is transmitted before leaving operating channel */
 483         ieee80211_flush_queues(local, NULL, false);
 484
 485         ieee80211_configure_filter(local);
 486
 487         /* We need to set power level at maximum rate for scanning. */
 488         ieee80211_hw_config(local, 0);
 489
 490         ieee80211_queue_delayed_work(&local->hw,
 491                                      &local->scan_work, 0);
 492
 493         return 0;
 494 }
 495
 496 static bool ieee80211_can_scan(struct ieee80211_local *local,
 497                                struct ieee80211_sub_if_data *sdata)
 498 {
 499         if (ieee80211_is_radar_required(local))
 500                 return false;
 501
 502         if (!list_empty(&local->roc_list))
 503                 return false;
 504
 505         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 506             sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
 507                 return false;
 508
 509         return true;
 510 }
 511
 512 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
 513 {
 514         lockdep_assert_held(&local->mtx);
 515
 516         if (!local->scan_req || local->scanning)
 517                 return;
 518
 519         if (!ieee80211_can_scan(local,
 520                                 rcu_dereference_protected(
 521                                         local->scan_sdata,
 522                                         lockdep_is_held(&local->mtx))))
 523                 return;
 524
 525         ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 526                                      round_jiffies_relative(0));
 527 }
 528
 529 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
 530                                             unsigned long *next_delay)
 531 {
 532         int i;
 533         struct ieee80211_sub_if_data *sdata;
 534         struct cfg80211_scan_request *scan_req;
 535         enum nl80211_band band = local->hw.conf.chandef.chan->band;
 536         u32 tx_flags;
 537
 538         scan_req = rcu_dereference_protected(local->scan_req,
 539                                              lockdep_is_held(&local->mtx));
 540
 541         tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
 542         if (scan_req->no_cck)
 543                 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
 544
 545         sdata = rcu_dereference_protected(local->scan_sdata,
 546                                           lockdep_is_held(&local->mtx));
 547
 548         for (i = 0; i < scan_req->n_ssids; i++)
 549                 ieee80211_send_probe_req(
 550                         sdata, local->scan_addr, scan_req->bssid,
 551                         scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
 552                         scan_req->ie, scan_req->ie_len,
 553                         scan_req->rates[band], false,
 554                         tx_flags, local->hw.conf.chandef.chan, true);
 555
 556         /*
 557          * After sending probe requests, wait for probe responses
 558          * on the channel.
 559          */
 560         *next_delay = IEEE80211_CHANNEL_TIME;
 561         local->next_scan_state = SCAN_DECISION;
 562 }
 563
 564 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 565                                   struct cfg80211_scan_request *req)
 566 {
 567         struct ieee80211_local *local = sdata->local;
 568         int rc;
 569
 570         lockdep_assert_held(&local->mtx);
 571
 572         if (local->scan_req || ieee80211_is_radar_required(local))
 573                 return -EBUSY;
 574
 575         if (!ieee80211_can_scan(local, sdata)) {
 576                 /* wait for the work to finish/time out */
 577                 rcu_assign_pointer(local->scan_req, req);
 578                 rcu_assign_pointer(local->scan_sdata, sdata);
 579                 return 0;
 580         }
 581
 582         if (local->ops->hw_scan) {
 583                 u8 *ies;
 584
 585                 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
 586
 587                 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 588                         int i, n_bands = 0;
 589                         u8 bands_counted = 0;
 590
 591                         for (i = 0; i < req->n_channels; i++) {
 592                                 if (bands_counted & BIT(req->channels[i]->band))
 593                                         continue;
 594                                 bands_counted |= BIT(req->channels[i]->band);
 595                                 n_bands++;
 596                         }
 597
 598                         local->hw_scan_ies_bufsize *= n_bands;
 599                 }
 600
 601                 local->hw_scan_req = kmalloc(
 602                                 sizeof(*local->hw_scan_req) +
 603                                 req->n_channels * sizeof(req->channels[0]) +
 604                                 local->hw_scan_ies_bufsize, GFP_KERNEL);
 605                 if (!local->hw_scan_req)
 606                         return -ENOMEM;
 607
 608                 local->hw_scan_req->req.ssids = req->ssids;
 609                 local->hw_scan_req->req.n_ssids = req->n_ssids;
 610                 ies = (u8 *)local->hw_scan_req +
 611                         sizeof(*local->hw_scan_req) +
 612                         req->n_channels * sizeof(req->channels[0]);
 613                 local->hw_scan_req->req.ie = ies;
 614                 local->hw_scan_req->req.flags = req->flags;
 615                 eth_broadcast_addr(local->hw_scan_req->req.bssid);
 616                 local->hw_scan_req->req.duration = req->duration;
 617                 local->hw_scan_req->req.duration_mandatory =
 618                         req->duration_mandatory;
 619
 620                 local->hw_scan_band = 0;
 621
 622                 /*
 623                  * After allocating local->hw_scan_req, we must
 624                  * go through until ieee80211_prep_hw_scan(), so
 625                  * anything that might be changed here and leave
 626                  * this function early must not go after this
 627                  * allocation.
 628                  */
 629         }
 630
 631         rcu_assign_pointer(local->scan_req, req);
 632         rcu_assign_pointer(local->scan_sdata, sdata);
 633
 634         if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 635                 get_random_mask_addr(local->scan_addr,
 636                                      req->mac_addr,
 637                                      req->mac_addr_mask);
 638         else
 639                 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
 640
 641         if (local->ops->hw_scan) {
 642                 __set_bit(SCAN_HW_SCANNING, &local->scanning);
 643         } else if ((req->n_channels == 1) &&
 644                    (req->channels[0] == local->_oper_chandef.chan)) {
 645                 /*
 646                  * If we are scanning only on the operating channel
 647                  * then we do not need to stop normal activities
 648                  */
 649                 unsigned long next_delay;
 650
 651                 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
 652
 653                 ieee80211_recalc_idle(local);
 654
 655                 /* Notify driver scan is starting, keep order of operations
 656                  * same as normal software scan, in case that matters. */
 657                 drv_sw_scan_start(local, sdata, local->scan_addr);
 658
 659                 ieee80211_configure_filter(local); /* accept probe-responses */
 660
 661                 /* We need to ensure power level is at max for scanning. */
 662                 ieee80211_hw_config(local, 0);
 663
 664                 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
 665                                                 IEEE80211_CHAN_RADAR)) ||
 666                     !req->n_ssids) {
 667                         next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 668                 } else {
 669                         ieee80211_scan_state_send_probe(local, &next_delay);
 670                         next_delay = IEEE80211_CHANNEL_TIME;
 671                 }
 672
 673                 /* Now, just wait a bit and we are all done! */
 674                 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 675                                              next_delay);
 676                 return 0;
 677         } else {
 678                 /* Do normal software scan */
 679                 __set_bit(SCAN_SW_SCANNING, &local->scanning);
 680         }
 681
 682         ieee80211_recalc_idle(local);
 683
 684         if (local->ops->hw_scan) {
 685                 WARN_ON(!ieee80211_prep_hw_scan(local));
 686                 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
 687         } else {
 688                 rc = ieee80211_start_sw_scan(local, sdata);
 689         }
 690
 691         if (rc) {
 692                 kfree(local->hw_scan_req);
 693                 local->hw_scan_req = NULL;
 694                 local->scanning = 0;
 695
 696                 ieee80211_recalc_idle(local);
 697
 698                 local->scan_req = NULL;
 699                 RCU_INIT_POINTER(local->scan_sdata, NULL);
 700         }
 701
 702         return rc;
 703 }
 704
 705 static unsigned long
 706 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
 707 {
 708         /*
 709          * TODO: channel switching also consumes quite some time,
 710          * add that delay as well to get a better estimation
 711          */
 712         if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
 713                 return IEEE80211_PASSIVE_CHANNEL_TIME;
 714         return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
 715 }
 716
 717 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
 718                                           unsigned long *next_delay)
 719 {
 720         bool associated = false;
 721         bool tx_empty = true;
 722         bool bad_latency;
 723         struct ieee80211_sub_if_data *sdata;
 724         struct ieee80211_channel *next_chan;
 725         enum mac80211_scan_state next_scan_state;
 726         struct cfg80211_scan_request *scan_req;
 727
 728         /*
 729          * check if at least one STA interface is associated,
 730          * check if at least one STA interface has pending tx frames
 731          * and grab the lowest used beacon interval
 732          */
 733         mutex_lock(&local->iflist_mtx);
 734         list_for_each_entry(sdata, &local->interfaces, list) {
 735                 if (!ieee80211_sdata_running(sdata))
 736                         continue;
 737
 738                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 739                         if (sdata->u.mgd.associated) {
 740                                 associated = true;
 741
 742                                 if (!qdisc_all_tx_empty(sdata->dev)) {
 743                                         tx_empty = false;
 744                                         break;
 745                                 }
 746                         }
 747                 }
 748         }
 749         mutex_unlock(&local->iflist_mtx);
 750
 751         scan_req = rcu_dereference_protected(local->scan_req,
 752                                              lockdep_is_held(&local->mtx));
 753
 754         next_chan = scan_req->channels[local->scan_channel_idx];
 755
 756         /*
 757          * we're currently scanning a different channel, let's
 758          * see if we can scan another channel without interfering
 759          * with the current traffic situation.
 760          *
 761          * Keep good latency, do not stay off-channel more than 125 ms.
 762          */
 763
 764         bad_latency = time_after(jiffies +
 765                                  ieee80211_scan_get_channel_time(next_chan),
 766                                  local->leave_oper_channel_time + HZ / 8);
 767
 768         if (associated && !tx_empty) {
 769                 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
 770                         next_scan_state = SCAN_ABORT;
 771                 else
 772                         next_scan_state = SCAN_SUSPEND;
 773         } else if (associated && bad_latency) {
 774                 next_scan_state = SCAN_SUSPEND;
 775         } else {
 776                 next_scan_state = SCAN_SET_CHANNEL;
 777         }
 778
 779         local->next_scan_state = next_scan_state;
 780
 781         *next_delay = 0;
 782 }
 783
 784 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
 785                                              unsigned long *next_delay)
 786 {
 787         int skip;
 788         struct ieee80211_channel *chan;
 789         enum nl80211_bss_scan_width oper_scan_width;
 790         struct cfg80211_scan_request *scan_req;
 791
 792         scan_req = rcu_dereference_protected(local->scan_req,
 793                                              lockdep_is_held(&local->mtx));
 794
 795         skip = 0;
 796         chan = scan_req->channels[local->scan_channel_idx];
 797
 798         local->scan_chandef.chan = chan;
 799         local->scan_chandef.center_freq1 = chan->center_freq;
 800         local->scan_chandef.center_freq2 = 0;
 801         switch (scan_req->scan_width) {
 802         case NL80211_BSS_CHAN_WIDTH_5:
 803                 local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
 804                 break;
 805         case NL80211_BSS_CHAN_WIDTH_10:
 806                 local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
 807                 break;
 808         case NL80211_BSS_CHAN_WIDTH_20:
 809                 /* If scanning on oper channel, use whatever channel-type
 810                  * is currently in use.
 811                  */
 812                 oper_scan_width = cfg80211_chandef_to_scan_width(
 813                                         &local->_oper_chandef);
 814                 if (chan == local->_oper_chandef.chan &&
 815                     oper_scan_width == scan_req->scan_width)
 816                         local->scan_chandef = local->_oper_chandef;
 817                 else
 818                         local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
 819                 break;
 820         }
 821
 822         if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
 823                 skip = 1;
 824
 825         /* advance state machine to next channel/band */
 826         local->scan_channel_idx++;
 827
 828         if (skip) {
 829                 /* if we skip this channel return to the decision state */
 830                 local->next_scan_state = SCAN_DECISION;
 831                 return;
 832         }
 833
 834         /*
 835          * Probe delay is used to update the NAV, cf. 11.1.3.2.2
 836          * (which unfortunately doesn't say _why_ step a) is done,
 837          * but it waits for the probe delay or until a frame is
 838          * received - and the received frame would update the NAV).
 839          * For now, we do not support waiting until a frame is
 840          * received.
 841          *
 842          * In any case, it is not necessary for a passive scan.
 843          */
 844         if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
 845             !scan_req->n_ssids) {
 846                 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 847                 local->next_scan_state = SCAN_DECISION;
 848                 return;
 849         }
 850
 851         /* active scan, send probes */
 852         *next_delay = IEEE80211_PROBE_DELAY;
 853         local->next_scan_state = SCAN_SEND_PROBE;
 854 }
 855
 856 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
 857                                          unsigned long *next_delay)
 858 {
 859         /* switch back to the operating channel */
 860         local->scan_chandef.chan = NULL;
 861         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 862
 863         /* disable PS */
 864         ieee80211_offchannel_return(local);
 865
 866         *next_delay = HZ / 5;
 867         /* afterwards, resume scan & go to next channel */
 868         local->next_scan_state = SCAN_RESUME;
 869 }
 870
 871 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
 872                                         unsigned long *next_delay)
 873 {
 874         ieee80211_offchannel_stop_vifs(local);
 875
 876         if (local->ops->flush) {
 877                 ieee80211_flush_queues(local, NULL, false);
 878                 *next_delay = 0;
 879         } else
 880                 *next_delay = HZ / 10;
 881
 882         /* remember when we left the operating channel */
 883         local->leave_oper_channel_time = jiffies;
 884
 885         /* advance to the next channel to be scanned */
 886         local->next_scan_state = SCAN_SET_CHANNEL;
 887 }
 888
 889 void ieee80211_scan_work(struct work_struct *work)
 890 {
 891         struct ieee80211_local *local =
 892                 container_of(work, struct ieee80211_local, scan_work.work);
 893         struct ieee80211_sub_if_data *sdata;
 894         struct cfg80211_scan_request *scan_req;
 895         unsigned long next_delay = 0;
 896         bool aborted;
 897
 898         mutex_lock(&local->mtx);
 899
 900         if (!ieee80211_can_run_worker(local)) {
 901                 aborted = true;
 902                 goto out_complete;
 903         }
 904
 905         sdata = rcu_dereference_protected(local->scan_sdata,
 906                                           lockdep_is_held(&local->mtx));
 907         scan_req = rcu_dereference_protected(local->scan_req,
 908                                              lockdep_is_held(&local->mtx));
 909
 910         /* When scanning on-channel, the first-callback means completed. */
 911         if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
 912                 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
 913                 goto out_complete;
 914         }
 915
 916         if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
 917                 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
 918                 goto out_complete;
 919         }
 920
 921         if (!sdata || !scan_req)
 922                 goto out;
 923
 924         if (!local->scanning) {
 925                 int rc;
 926
 927                 RCU_INIT_POINTER(local->scan_req, NULL);
 928                 RCU_INIT_POINTER(local->scan_sdata, NULL);
 929
 930                 rc = __ieee80211_start_scan(sdata, scan_req);
 931                 if (rc) {
 932                         /* need to complete scan in cfg80211 */
 933                         rcu_assign_pointer(local->scan_req, scan_req);
 934                         aborted = true;
 935                         goto out_complete;
 936                 } else
 937                         goto out;
 938         }
 939
 940         /*
 941          * as long as no delay is required advance immediately
 942          * without scheduling a new work
 943          */
 944         do {
 945                 if (!ieee80211_sdata_running(sdata)) {
 946                         aborted = true;
 947                         goto out_complete;
 948                 }
 949
 950                 switch (local->next_scan_state) {
 951                 case SCAN_DECISION:
 952                         /* if no more bands/channels left, complete scan */
 953                         if (local->scan_channel_idx >= scan_req->n_channels) {
 954                                 aborted = false;
 955                                 goto out_complete;
 956                         }
 957                         ieee80211_scan_state_decision(local, &next_delay);
 958                         break;
 959                 case SCAN_SET_CHANNEL:
 960                         ieee80211_scan_state_set_channel(local, &next_delay);
 961                         break;
 962                 case SCAN_SEND_PROBE:
 963                         ieee80211_scan_state_send_probe(local, &next_delay);
 964                         break;
 965                 case SCAN_SUSPEND:
 966                         ieee80211_scan_state_suspend(local, &next_delay);
 967                         break;
 968                 case SCAN_RESUME:
 969                         ieee80211_scan_state_resume(local, &next_delay);
 970                         break;
 971                 case SCAN_ABORT:
 972                         aborted = true;
 973                         goto out_complete;
 974                 }
 975         } while (next_delay == 0);
 976
 977         ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
 978         goto out;
 979
 980 out_complete:
 981         __ieee80211_scan_completed(&local->hw, aborted);
 982 out:
 983         mutex_unlock(&local->mtx);
 984 }
 985
 986 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
 987                            struct cfg80211_scan_request *req)
 988 {
 989         int res;
 990
 991         mutex_lock(&sdata->local->mtx);
 992         res = __ieee80211_start_scan(sdata, req);
 993         mutex_unlock(&sdata->local->mtx);
 994
 995         return res;
 996 }
 997
 998 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
 999                                 const u8 *ssid, u8 ssid_len,
1000                                 struct ieee80211_channel **channels,
1001                                 unsigned int n_channels,
1002                                 enum nl80211_bss_scan_width scan_width)
1003 {
1004         struct ieee80211_local *local = sdata->local;
1005         int ret = -EBUSY, i, n_ch = 0;
1006         enum nl80211_band band;
1007
1008         mutex_lock(&local->mtx);
1009
1010         /* busy scanning */
1011         if (local->scan_req)
1012                 goto unlock;
1013
1014         /* fill internal scan request */
1015         if (!channels) {
1016                 int max_n;
1017
1018                 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1019                         if (!local->hw.wiphy->bands[band])
1020                                 continue;
1021
1022                         max_n = local->hw.wiphy->bands[band]->n_channels;
1023                         for (i = 0; i < max_n; i++) {
1024                                 struct ieee80211_channel *tmp_ch =
1025                                     &local->hw.wiphy->bands[band]->channels[i];
1026
1027                                 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1028                                                      IEEE80211_CHAN_DISABLED))
1029                                         continue;
1030
1031                                 local->int_scan_req->channels[n_ch] = tmp_ch;
1032                                 n_ch++;
1033                         }
1034                 }
1035
1036                 if (WARN_ON_ONCE(n_ch == 0))
1037                         goto unlock;
1038
1039                 local->int_scan_req->n_channels = n_ch;
1040         } else {
1041                 for (i = 0; i < n_channels; i++) {
1042                         if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1043                                                   IEEE80211_CHAN_DISABLED))
1044                                 continue;
1045
1046                         local->int_scan_req->channels[n_ch] = channels[i];
1047                         n_ch++;
1048                 }
1049
1050                 if (WARN_ON_ONCE(n_ch == 0))
1051                         goto unlock;
1052
1053                 local->int_scan_req->n_channels = n_ch;
1054         }
1055
1056         local->int_scan_req->ssids = &local->scan_ssid;
1057         local->int_scan_req->n_ssids = 1;
1058         local->int_scan_req->scan_width = scan_width;
1059         memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1060         local->int_scan_req->ssids[0].ssid_len = ssid_len;
1061
1062         ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1063  unlock:
1064         mutex_unlock(&local->mtx);
1065         return ret;
1066 }
1067
1068 /*
1069  * Only call this function when a scan can't be queued -- under RTNL.
1070  */
1071 void ieee80211_scan_cancel(struct ieee80211_local *local)
1072 {
1073         /*
1074          * We are canceling software scan, or deferred scan that was not
1075          * yet really started (see __ieee80211_start_scan ).
1076          *
1077          * Regarding hardware scan:
1078          * - we can not call  __ieee80211_scan_completed() as when
1079          *   SCAN_HW_SCANNING bit is set this function change
1080          *   local->hw_scan_req to operate on 5G band, what race with
1081          *   driver which can use local->hw_scan_req
1082          *
1083          * - we can not cancel scan_work since driver can schedule it
1084          *   by ieee80211_scan_completed(..., true) to finish scan
1085          *
1086          * Hence we only call the cancel_hw_scan() callback, but the low-level
1087          * driver is still responsible for calling ieee80211_scan_completed()
1088          * after the scan was completed/aborted.
1089          */
1090
1091         mutex_lock(&local->mtx);
1092         if (!local->scan_req)
1093                 goto out;
1094
1095         /*
1096          * We have a scan running and the driver already reported completion,
1097          * but the worker hasn't run yet or is stuck on the mutex - mark it as
1098          * cancelled.
1099          */
1100         if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1101             test_bit(SCAN_COMPLETED, &local->scanning)) {
1102                 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1103                 goto out;
1104         }
1105
1106         if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1107                 /*
1108                  * Make sure that __ieee80211_scan_completed doesn't trigger a
1109                  * scan on another band.
1110                  */
1111                 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1112                 if (local->ops->cancel_hw_scan)
1113                         drv_cancel_hw_scan(local,
1114                                 rcu_dereference_protected(local->scan_sdata,
1115                                                 lockdep_is_held(&local->mtx)));
1116                 goto out;
1117         }
1118
1119         /*
1120          * If the work is currently running, it must be blocked on
1121          * the mutex, but we'll set scan_sdata = NULL and it'll
1122          * simply exit once it acquires the mutex.
1123          */
1124         cancel_delayed_work(&local->scan_work);
1125         /* and clean up */
1126         memset(&local->scan_info, 0, sizeof(local->scan_info));
1127         __ieee80211_scan_completed(&local->hw, true);
1128 out:
1129         mutex_unlock(&local->mtx);
1130 }
1131
1132 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1133                                         struct cfg80211_sched_scan_request *req)
1134 {
1135         struct ieee80211_local *local = sdata->local;
1136         struct ieee80211_scan_ies sched_scan_ies = {};
1137         struct cfg80211_chan_def chandef;
1138         int ret, i, iebufsz, num_bands = 0;
1139         u32 rate_masks[NUM_NL80211_BANDS] = {};
1140         u8 bands_used = 0;
1141         u8 *ie;
1142
1143         iebufsz = local->scan_ies_len + req->ie_len;
1144
1145         lockdep_assert_held(&local->mtx);
1146
1147         if (!local->ops->sched_scan_start)
1148                 return -ENOTSUPP;
1149
1150         for (i = 0; i < NUM_NL80211_BANDS; i++) {
1151                 if (local->hw.wiphy->bands[i]) {
1152                         bands_used |= BIT(i);
1153                         rate_masks[i] = (u32) -1;
1154                         num_bands++;
1155                 }
1156         }
1157
1158         ie = kzalloc(num_bands * iebufsz, GFP_KERNEL);
1159         if (!ie) {
1160                 ret = -ENOMEM;
1161                 goto out;
1162         }
1163
1164         ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1165
1166         ieee80211_build_preq_ies(local, ie, num_bands * iebufsz,
1167                                  &sched_scan_ies, req->ie,
1168                                  req->ie_len, bands_used, rate_masks, &chandef);
1169
1170         ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1171         if (ret == 0) {
1172                 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1173                 rcu_assign_pointer(local->sched_scan_req, req);
1174         }
1175
1176         kfree(ie);
1177
1178 out:
1179         if (ret) {
1180                 /* Clean in case of failure after HW restart or upon resume. */
1181                 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1182                 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1183         }
1184
1185         return ret;
1186 }
1187
1188 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1189                                        struct cfg80211_sched_scan_request *req)
1190 {
1191         struct ieee80211_local *local = sdata->local;
1192         int ret;
1193
1194         mutex_lock(&local->mtx);
1195
1196         if (rcu_access_pointer(local->sched_scan_sdata)) {
1197                 mutex_unlock(&local->mtx);
1198                 return -EBUSY;
1199         }
1200
1201         ret = __ieee80211_request_sched_scan_start(sdata, req);
1202
1203         mutex_unlock(&local->mtx);
1204         return ret;
1205 }
1206
1207 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1208 {
1209         struct ieee80211_sub_if_data *sched_scan_sdata;
1210         int ret = -ENOENT;
1211
1212         mutex_lock(&local->mtx);
1213
1214         if (!local->ops->sched_scan_stop) {
1215                 ret = -ENOTSUPP;
1216                 goto out;
1217         }
1218
1219         /* We don't want to restart sched scan anymore. */
1220         RCU_INIT_POINTER(local->sched_scan_req, NULL);
1221
1222         sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1223                                                 lockdep_is_held(&local->mtx));
1224         if (sched_scan_sdata) {
1225                 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1226                 if (!ret)
1227                         RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1228         }
1229 out:
1230         mutex_unlock(&local->mtx);
1231
1232         return ret;
1233 }
1234
1235 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1236 {
1237         struct ieee80211_local *local = hw_to_local(hw);
1238
1239         trace_api_sched_scan_results(local);
1240
1241         cfg80211_sched_scan_results(hw->wiphy, 0);
1242 }
1243 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1244
1245 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1246 {
1247         mutex_lock(&local->mtx);
1248
1249         if (!rcu_access_pointer(local->sched_scan_sdata)) {
1250                 mutex_unlock(&local->mtx);
1251                 return;
1252         }
1253
1254         RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1255
1256         /* If sched scan was aborted by the driver. */
1257         RCU_INIT_POINTER(local->sched_scan_req, NULL);
1258
1259         mutex_unlock(&local->mtx);
1260
1261         cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1262 }
1263
1264 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1265 {
1266         struct ieee80211_local *local =
1267                 container_of(work, struct ieee80211_local,
1268                              sched_scan_stopped_work);
1269
1270         ieee80211_sched_scan_end(local);
1271 }
1272
1273 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1274 {
1275         struct ieee80211_local *local = hw_to_local(hw);
1276
1277         trace_api_sched_scan_stopped(local);
1278
1279         /*
1280          * this shouldn't really happen, so for simplicity
1281          * simply ignore it, and let mac80211 reconfigure
1282          * the sched scan later on.
1283          */
1284         if (local->in_reconfig)
1285                 return;
1286
1287         schedule_work(&local->sched_scan_stopped_work);
1288 }
1289 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);