mac80211/scan.c

   1 /*
   2  * Scanning implementation
   3  *
   4  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
   5  * Copyright 2004, Instant802 Networks, Inc.
   6  * Copyright 2005, Devicescape Software, Inc.
   7  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   9  * Copyright 2013-2015  Intel Mobile Communications GmbH
  10  * Copyright 2016  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 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
 187 {
 188         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
 189         struct ieee80211_sub_if_data *sdata1, *sdata2;
 190         struct ieee80211_mgmt *mgmt = (void *)skb->data;
 191         struct ieee80211_bss *bss;
 192         u8 *elements;
 193         struct ieee80211_channel *channel;
 194         size_t baselen;
 195         struct ieee802_11_elems elems;
 196
 197         if (skb->len < 24 ||
 198             (!ieee80211_is_probe_resp(mgmt->frame_control) &&
 199              !ieee80211_is_beacon(mgmt->frame_control)))
 200                 return;
 201
 202         sdata1 = rcu_dereference(local->scan_sdata);
 203         sdata2 = rcu_dereference(local->sched_scan_sdata);
 204
 205         if (likely(!sdata1 && !sdata2))
 206                 return;
 207
 208         if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) {
 209                 /*
 210                  * we were passive scanning because of radar/no-IR, but
 211                  * the beacon/proberesp rx gives us an opportunity to upgrade
 212                  * to active scan
 213                  */
 214                  set_bit(SCAN_BEACON_DONE, &local->scanning);
 215                  ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
 216         }
 217
 218         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 219                 struct cfg80211_scan_request *scan_req;
 220                 struct cfg80211_sched_scan_request *sched_scan_req;
 221
 222                 scan_req = rcu_dereference(local->scan_req);
 223                 sched_scan_req = rcu_dereference(local->sched_scan_req);
 224
 225                 /* ignore ProbeResp to foreign address unless scanning
 226                  * with randomised address
 227                  */
 228                 if (!(sdata1 &&
 229                       (ether_addr_equal(mgmt->da, sdata1->vif.addr) ||
 230                        scan_req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)) &&
 231                     !(sdata2 &&
 232                       (ether_addr_equal(mgmt->da, sdata2->vif.addr) ||
 233                        sched_scan_req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)))
 234                         return;
 235
 236                 elements = mgmt->u.probe_resp.variable;
 237                 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
 238         } else {
 239                 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
 240                 elements = mgmt->u.beacon.variable;
 241         }
 242
 243         if (baselen > skb->len)
 244                 return;
 245
 246         ieee802_11_parse_elems(elements, skb->len - baselen, false, &elems);
 247
 248         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
 249
 250         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 251                 return;
 252
 253         bss = ieee80211_bss_info_update(local, rx_status,
 254                                         mgmt, skb->len, &elems,
 255                                         channel);
 256         if (bss)
 257                 ieee80211_rx_bss_put(local, bss);
 258 }
 259
 260 static void
 261 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
 262                                enum nl80211_bss_scan_width scan_width)
 263 {
 264         memset(chandef, 0, sizeof(*chandef));
 265         switch (scan_width) {
 266         case NL80211_BSS_CHAN_WIDTH_5:
 267                 chandef->width = NL80211_CHAN_WIDTH_5;
 268                 break;
 269         case NL80211_BSS_CHAN_WIDTH_10:
 270                 chandef->width = NL80211_CHAN_WIDTH_10;
 271                 break;
 272         default:
 273                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 274                 break;
 275         }
 276 }
 277
 278 /* return false if no more work */
 279 static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
 280 {
 281         struct cfg80211_scan_request *req;
 282         struct cfg80211_chan_def chandef;
 283         u8 bands_used = 0;
 284         int i, ielen, n_chans;
 285
 286         req = rcu_dereference_protected(local->scan_req,
 287                                         lockdep_is_held(&local->mtx));
 288
 289         if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
 290                 return false;
 291
 292         if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 293                 for (i = 0; i < req->n_channels; i++) {
 294                         local->hw_scan_req->req.channels[i] = req->channels[i];
 295                         bands_used |= BIT(req->channels[i]->band);
 296                 }
 297
 298                 n_chans = req->n_channels;
 299         } else {
 300                 do {
 301                         if (local->hw_scan_band == NUM_NL80211_BANDS)
 302                                 return false;
 303
 304                         n_chans = 0;
 305
 306                         for (i = 0; i < req->n_channels; i++) {
 307                                 if (req->channels[i]->band !=
 308                                     local->hw_scan_band)
 309                                         continue;
 310                                 local->hw_scan_req->req.channels[n_chans] =
 311                                                         req->channels[i];
 312                                 n_chans++;
 313                                 bands_used |= BIT(req->channels[i]->band);
 314                         }
 315
 316                         local->hw_scan_band++;
 317                 } while (!n_chans);
 318         }
 319
 320         local->hw_scan_req->req.n_channels = n_chans;
 321         ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
 322
 323         ielen = ieee80211_build_preq_ies(local,
 324                                          (u8 *)local->hw_scan_req->req.ie,
 325                                          local->hw_scan_ies_bufsize,
 326                                          &local->hw_scan_req->ies,
 327                                          req->ie, req->ie_len,
 328                                          bands_used, req->rates, &chandef);
 329         local->hw_scan_req->req.ie_len = ielen;
 330         local->hw_scan_req->req.no_cck = req->no_cck;
 331         ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
 332         ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
 333                         req->mac_addr_mask);
 334         ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
 335
 336         return true;
 337 }
 338
 339 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 340 {
 341         struct ieee80211_local *local = hw_to_local(hw);
 342         bool hw_scan = local->ops->hw_scan;
 343         bool was_scanning = local->scanning;
 344         struct cfg80211_scan_request *scan_req;
 345         struct ieee80211_sub_if_data *scan_sdata;
 346         struct ieee80211_sub_if_data *sdata;
 347
 348         lockdep_assert_held(&local->mtx);
 349
 350         /*
 351          * It's ok to abort a not-yet-running scan (that
 352          * we have one at all will be verified by checking
 353          * local->scan_req next), but not to complete it
 354          * successfully.
 355          */
 356         if (WARN_ON(!local->scanning && !aborted))
 357                 aborted = true;
 358
 359         if (WARN_ON(!local->scan_req))
 360                 return;
 361
 362         if (hw_scan && !aborted &&
 363             !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
 364             ieee80211_prep_hw_scan(local)) {
 365                 int rc;
 366
 367                 rc = drv_hw_scan(local,
 368                         rcu_dereference_protected(local->scan_sdata,
 369                                                   lockdep_is_held(&local->mtx)),
 370                         local->hw_scan_req);
 371
 372                 if (rc == 0)
 373                         return;
 374
 375                 /* HW scan failed and is going to be reported as aborted,
 376                  * so clear old scan info.
 377                  */
 378                 memset(&local->scan_info, 0, sizeof(local->scan_info));
 379                 aborted = true;
 380         }
 381
 382         kfree(local->hw_scan_req);
 383         local->hw_scan_req = NULL;
 384
 385         scan_req = rcu_dereference_protected(local->scan_req,
 386                                              lockdep_is_held(&local->mtx));
 387
 388         RCU_INIT_POINTER(local->scan_req, NULL);
 389
 390         scan_sdata = rcu_dereference_protected(local->scan_sdata,
 391                                                lockdep_is_held(&local->mtx));
 392         RCU_INIT_POINTER(local->scan_sdata, NULL);
 393
 394         local->scanning = 0;
 395         local->scan_chandef.chan = NULL;
 396
 397         synchronize_rcu();
 398
 399         if (scan_req != local->int_scan_req) {
 400                 local->scan_info.aborted = aborted;
 401                 cfg80211_scan_done(scan_req, &local->scan_info);
 402         }
 403
 404         /* Set power back to normal operating levels. */
 405         ieee80211_hw_config(local, 0);
 406
 407         if (!hw_scan) {
 408                 ieee80211_configure_filter(local);
 409                 drv_sw_scan_complete(local, scan_sdata);
 410                 ieee80211_offchannel_return(local);
 411         }
 412
 413         ieee80211_recalc_idle(local);
 414
 415         ieee80211_mlme_notify_scan_completed(local);
 416         ieee80211_ibss_notify_scan_completed(local);
 417
 418         /* Requeue all the work that might have been ignored while
 419          * the scan was in progress; if there was none this will
 420          * just be a no-op for the particular interface.
 421          */
 422         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 423                 if (ieee80211_sdata_running(sdata))
 424                         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 425         }
 426
 427         if (was_scanning)
 428                 ieee80211_start_next_roc(local);
 429 }
 430
 431 void ieee80211_scan_completed(struct ieee80211_hw *hw,
 432                               struct cfg80211_scan_info *info)
 433 {
 434         struct ieee80211_local *local = hw_to_local(hw);
 435
 436         trace_api_scan_completed(local, info->aborted);
 437
 438         set_bit(SCAN_COMPLETED, &local->scanning);
 439         if (info->aborted)
 440                 set_bit(SCAN_ABORTED, &local->scanning);
 441
 442         memcpy(&local->scan_info, info, sizeof(*info));
 443
 444         ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
 445 }
 446 EXPORT_SYMBOL(ieee80211_scan_completed);
 447
 448 static int ieee80211_start_sw_scan(struct ieee80211_local *local,
 449                                    struct ieee80211_sub_if_data *sdata)
 450 {
 451         /* Software scan is not supported in multi-channel cases */
 452         if (local->use_chanctx)
 453                 return -EOPNOTSUPP;
 454
 455         /*
 456          * Hardware/driver doesn't support hw_scan, so use software
 457          * scanning instead. First send a nullfunc frame with power save
 458          * bit on so that AP will buffer the frames for us while we are not
 459          * listening, then send probe requests to each channel and wait for
 460          * the responses. After all channels are scanned, tune back to the
 461          * original channel and send a nullfunc frame with power save bit
 462          * off to trigger the AP to send us all the buffered frames.
 463          *
 464          * Note that while local->sw_scanning is true everything else but
 465          * nullfunc frames and probe requests will be dropped in
 466          * ieee80211_tx_h_check_assoc().
 467          */
 468         drv_sw_scan_start(local, sdata, local->scan_addr);
 469
 470         local->leave_oper_channel_time = jiffies;
 471         local->next_scan_state = SCAN_DECISION;
 472         local->scan_channel_idx = 0;
 473
 474         ieee80211_offchannel_stop_vifs(local);
 475
 476         /* ensure nullfunc is transmitted before leaving operating channel */
 477         ieee80211_flush_queues(local, NULL, false);
 478
 479         ieee80211_configure_filter(local);
 480
 481         /* We need to set power level at maximum rate for scanning. */
 482         ieee80211_hw_config(local, 0);
 483
 484         ieee80211_queue_delayed_work(&local->hw,
 485                                      &local->scan_work, 0);
 486
 487         return 0;
 488 }
 489
 490 static bool ieee80211_can_scan(struct ieee80211_local *local,
 491                                struct ieee80211_sub_if_data *sdata)
 492 {
 493         if (ieee80211_is_radar_required(local))
 494                 return false;
 495
 496         if (!list_empty(&local->roc_list))
 497                 return false;
 498
 499         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 500             sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
 501                 return false;
 502
 503         return true;
 504 }
 505
 506 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
 507 {
 508         lockdep_assert_held(&local->mtx);
 509
 510         if (!local->scan_req || local->scanning)
 511                 return;
 512
 513         if (!ieee80211_can_scan(local,
 514                                 rcu_dereference_protected(
 515                                         local->scan_sdata,
 516                                         lockdep_is_held(&local->mtx))))
 517                 return;
 518
 519         ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 520                                      round_jiffies_relative(0));
 521 }
 522
 523 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
 524                                             unsigned long *next_delay)
 525 {
 526         int i;
 527         struct ieee80211_sub_if_data *sdata;
 528         struct cfg80211_scan_request *scan_req;
 529         enum nl80211_band band = local->hw.conf.chandef.chan->band;
 530         u32 tx_flags;
 531
 532         scan_req = rcu_dereference_protected(local->scan_req,
 533                                              lockdep_is_held(&local->mtx));
 534
 535         tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
 536         if (scan_req->no_cck)
 537                 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
 538
 539         sdata = rcu_dereference_protected(local->scan_sdata,
 540                                           lockdep_is_held(&local->mtx));
 541
 542         for (i = 0; i < scan_req->n_ssids; i++)
 543                 ieee80211_send_probe_req(
 544                         sdata, local->scan_addr, scan_req->bssid,
 545                         scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
 546                         scan_req->ie, scan_req->ie_len,
 547                         scan_req->rates[band], false,
 548                         tx_flags, local->hw.conf.chandef.chan, true);
 549
 550         /*
 551          * After sending probe requests, wait for probe responses
 552          * on the channel.
 553          */
 554         *next_delay = IEEE80211_CHANNEL_TIME;
 555         local->next_scan_state = SCAN_DECISION;
 556 }
 557
 558 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 559                                   struct cfg80211_scan_request *req)
 560 {
 561         struct ieee80211_local *local = sdata->local;
 562         int rc;
 563
 564         lockdep_assert_held(&local->mtx);
 565
 566         if (local->scan_req || ieee80211_is_radar_required(local))
 567                 return -EBUSY;
 568
 569         if (!ieee80211_can_scan(local, sdata)) {
 570                 /* wait for the work to finish/time out */
 571                 rcu_assign_pointer(local->scan_req, req);
 572                 rcu_assign_pointer(local->scan_sdata, sdata);
 573                 return 0;
 574         }
 575
 576         if (local->ops->hw_scan) {
 577                 u8 *ies;
 578
 579                 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
 580
 581                 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 582                         int i, n_bands = 0;
 583                         u8 bands_counted = 0;
 584
 585                         for (i = 0; i < req->n_channels; i++) {
 586                                 if (bands_counted & BIT(req->channels[i]->band))
 587                                         continue;
 588                                 bands_counted |= BIT(req->channels[i]->band);
 589                                 n_bands++;
 590                         }
 591
 592                         local->hw_scan_ies_bufsize *= n_bands;
 593                 }
 594
 595                 local->hw_scan_req = kmalloc(
 596                                 sizeof(*local->hw_scan_req) +
 597                                 req->n_channels * sizeof(req->channels[0]) +
 598                                 local->hw_scan_ies_bufsize, GFP_KERNEL);
 599                 if (!local->hw_scan_req)
 600                         return -ENOMEM;
 601
 602                 local->hw_scan_req->req.ssids = req->ssids;
 603                 local->hw_scan_req->req.n_ssids = req->n_ssids;
 604                 ies = (u8 *)local->hw_scan_req +
 605                         sizeof(*local->hw_scan_req) +
 606                         req->n_channels * sizeof(req->channels[0]);
 607                 local->hw_scan_req->req.ie = ies;
 608                 local->hw_scan_req->req.flags = req->flags;
 609                 eth_broadcast_addr(local->hw_scan_req->req.bssid);
 610                 local->hw_scan_req->req.duration = req->duration;
 611                 local->hw_scan_req->req.duration_mandatory =
 612                         req->duration_mandatory;
 613
 614                 local->hw_scan_band = 0;
 615
 616                 /*
 617                  * After allocating local->hw_scan_req, we must
 618                  * go through until ieee80211_prep_hw_scan(), so
 619                  * anything that might be changed here and leave
 620                  * this function early must not go after this
 621                  * allocation.
 622                  */
 623         }
 624
 625         rcu_assign_pointer(local->scan_req, req);
 626         rcu_assign_pointer(local->scan_sdata, sdata);
 627
 628         if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 629                 get_random_mask_addr(local->scan_addr,
 630                                      req->mac_addr,
 631                                      req->mac_addr_mask);
 632         else
 633                 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
 634
 635         if (local->ops->hw_scan) {
 636                 __set_bit(SCAN_HW_SCANNING, &local->scanning);
 637         } else if ((req->n_channels == 1) &&
 638                    (req->channels[0] == local->_oper_chandef.chan)) {
 639                 /*
 640                  * If we are scanning only on the operating channel
 641                  * then we do not need to stop normal activities
 642                  */
 643                 unsigned long next_delay;
 644
 645                 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
 646
 647                 ieee80211_recalc_idle(local);
 648
 649                 /* Notify driver scan is starting, keep order of operations
 650                  * same as normal software scan, in case that matters. */
 651                 drv_sw_scan_start(local, sdata, local->scan_addr);
 652
 653                 ieee80211_configure_filter(local); /* accept probe-responses */
 654
 655                 /* We need to ensure power level is at max for scanning. */
 656                 ieee80211_hw_config(local, 0);
 657
 658                 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
 659                                                 IEEE80211_CHAN_RADAR)) ||
 660                     !req->n_ssids) {
 661                         next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 662                         if (req->n_ssids)
 663                                 set_bit(SCAN_BEACON_WAIT, &local->scanning);
 664                 } else {
 665                         ieee80211_scan_state_send_probe(local, &next_delay);
 666                         next_delay = IEEE80211_CHANNEL_TIME;
 667                 }
 668
 669                 /* Now, just wait a bit and we are all done! */
 670                 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 671                                              next_delay);
 672                 return 0;
 673         } else {
 674                 /* Do normal software scan */
 675                 __set_bit(SCAN_SW_SCANNING, &local->scanning);
 676         }
 677
 678         ieee80211_recalc_idle(local);
 679
 680         if (local->ops->hw_scan) {
 681                 WARN_ON(!ieee80211_prep_hw_scan(local));
 682                 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
 683         } else {
 684                 rc = ieee80211_start_sw_scan(local, sdata);
 685         }
 686
 687         if (rc) {
 688                 kfree(local->hw_scan_req);
 689                 local->hw_scan_req = NULL;
 690                 local->scanning = 0;
 691
 692                 ieee80211_recalc_idle(local);
 693
 694                 local->scan_req = NULL;
 695                 RCU_INIT_POINTER(local->scan_sdata, NULL);
 696         }
 697
 698         return rc;
 699 }
 700
 701 static unsigned long
 702 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
 703 {
 704         /*
 705          * TODO: channel switching also consumes quite some time,
 706          * add that delay as well to get a better estimation
 707          */
 708         if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
 709                 return IEEE80211_PASSIVE_CHANNEL_TIME;
 710         return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
 711 }
 712
 713 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
 714                                           unsigned long *next_delay)
 715 {
 716         bool associated = false;
 717         bool tx_empty = true;
 718         bool bad_latency;
 719         struct ieee80211_sub_if_data *sdata;
 720         struct ieee80211_channel *next_chan;
 721         enum mac80211_scan_state next_scan_state;
 722         struct cfg80211_scan_request *scan_req;
 723
 724         /*
 725          * check if at least one STA interface is associated,
 726          * check if at least one STA interface has pending tx frames
 727          * and grab the lowest used beacon interval
 728          */
 729         mutex_lock(&local->iflist_mtx);
 730         list_for_each_entry(sdata, &local->interfaces, list) {
 731                 if (!ieee80211_sdata_running(sdata))
 732                         continue;
 733
 734                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 735                         if (sdata->u.mgd.associated) {
 736                                 associated = true;
 737
 738                                 if (!qdisc_all_tx_empty(sdata->dev)) {
 739                                         tx_empty = false;
 740                                         break;
 741                                 }
 742                         }
 743                 }
 744         }
 745         mutex_unlock(&local->iflist_mtx);
 746
 747         scan_req = rcu_dereference_protected(local->scan_req,
 748                                              lockdep_is_held(&local->mtx));
 749
 750         next_chan = scan_req->channels[local->scan_channel_idx];
 751
 752         /*
 753          * we're currently scanning a different channel, let's
 754          * see if we can scan another channel without interfering
 755          * with the current traffic situation.
 756          *
 757          * Keep good latency, do not stay off-channel more than 125 ms.
 758          */
 759
 760         bad_latency = time_after(jiffies +
 761                                  ieee80211_scan_get_channel_time(next_chan),
 762                                  local->leave_oper_channel_time + HZ / 8);
 763
 764         if (associated && !tx_empty) {
 765                 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
 766                         next_scan_state = SCAN_ABORT;
 767                 else
 768                         next_scan_state = SCAN_SUSPEND;
 769         } else if (associated && bad_latency) {
 770                 next_scan_state = SCAN_SUSPEND;
 771         } else {
 772                 next_scan_state = SCAN_SET_CHANNEL;
 773         }
 774
 775         local->next_scan_state = next_scan_state;
 776
 777         *next_delay = 0;
 778 }
 779
 780 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
 781                                              unsigned long *next_delay)
 782 {
 783         int skip;
 784         struct ieee80211_channel *chan;
 785         enum nl80211_bss_scan_width oper_scan_width;
 786         struct cfg80211_scan_request *scan_req;
 787
 788         scan_req = rcu_dereference_protected(local->scan_req,
 789                                              lockdep_is_held(&local->mtx));
 790
 791         skip = 0;
 792         chan = scan_req->channels[local->scan_channel_idx];
 793
 794         local->scan_chandef.chan = chan;
 795         local->scan_chandef.center_freq1 = chan->center_freq;
 796         local->scan_chandef.center_freq2 = 0;
 797         switch (scan_req->scan_width) {
 798         case NL80211_BSS_CHAN_WIDTH_5:
 799                 local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
 800                 break;
 801         case NL80211_BSS_CHAN_WIDTH_10:
 802                 local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
 803                 break;
 804         case NL80211_BSS_CHAN_WIDTH_20:
 805                 /* If scanning on oper channel, use whatever channel-type
 806                  * is currently in use.
 807                  */
 808                 oper_scan_width = cfg80211_chandef_to_scan_width(
 809                                         &local->_oper_chandef);
 810                 if (chan == local->_oper_chandef.chan &&
 811                     oper_scan_width == scan_req->scan_width)
 812                         local->scan_chandef = local->_oper_chandef;
 813                 else
 814                         local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
 815                 break;
 816         }
 817
 818         if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
 819                 skip = 1;
 820
 821         /* advance state machine to next channel/band */
 822         local->scan_channel_idx++;
 823
 824         if (skip) {
 825                 /* if we skip this channel return to the decision state */
 826                 local->next_scan_state = SCAN_DECISION;
 827                 return;
 828         }
 829
 830         /*
 831          * Probe delay is used to update the NAV, cf. 11.1.3.2.2
 832          * (which unfortunately doesn't say _why_ step a) is done,
 833          * but it waits for the probe delay or until a frame is
 834          * received - and the received frame would update the NAV).
 835          * For now, we do not support waiting until a frame is
 836          * received.
 837          *
 838          * In any case, it is not necessary for a passive scan.
 839          */
 840         if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
 841             !scan_req->n_ssids) {
 842                 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 843                 local->next_scan_state = SCAN_DECISION;
 844                 if (scan_req->n_ssids)
 845                         set_bit(SCAN_BEACON_WAIT, &local->scanning);
 846                 return;
 847         }
 848
 849         /* active scan, send probes */
 850         *next_delay = IEEE80211_PROBE_DELAY;
 851         local->next_scan_state = SCAN_SEND_PROBE;
 852 }
 853
 854 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
 855                                          unsigned long *next_delay)
 856 {
 857         /* switch back to the operating channel */
 858         local->scan_chandef.chan = NULL;
 859         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 860
 861         /* disable PS */
 862         ieee80211_offchannel_return(local);
 863
 864         *next_delay = HZ / 5;
 865         /* afterwards, resume scan & go to next channel */
 866         local->next_scan_state = SCAN_RESUME;
 867 }
 868
 869 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
 870                                         unsigned long *next_delay)
 871 {
 872         ieee80211_offchannel_stop_vifs(local);
 873
 874         if (local->ops->flush) {
 875                 ieee80211_flush_queues(local, NULL, false);
 876                 *next_delay = 0;
 877         } else
 878                 *next_delay = HZ / 10;
 879
 880         /* remember when we left the operating channel */
 881         local->leave_oper_channel_time = jiffies;
 882
 883         /* advance to the next channel to be scanned */
 884         local->next_scan_state = SCAN_SET_CHANNEL;
 885 }
 886
 887 void ieee80211_scan_work(struct work_struct *work)
 888 {
 889         struct ieee80211_local *local =
 890                 container_of(work, struct ieee80211_local, scan_work.work);
 891         struct ieee80211_sub_if_data *sdata;
 892         struct cfg80211_scan_request *scan_req;
 893         unsigned long next_delay = 0;
 894         bool aborted;
 895
 896         mutex_lock(&local->mtx);
 897
 898         if (!ieee80211_can_run_worker(local)) {
 899                 aborted = true;
 900                 goto out_complete;
 901         }
 902
 903         sdata = rcu_dereference_protected(local->scan_sdata,
 904                                           lockdep_is_held(&local->mtx));
 905         scan_req = rcu_dereference_protected(local->scan_req,
 906                                              lockdep_is_held(&local->mtx));
 907
 908         /* When scanning on-channel, the first-callback means completed. */
 909         if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
 910                 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
 911                 goto out_complete;
 912         }
 913
 914         if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
 915                 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
 916                 goto out_complete;
 917         }
 918
 919         if (!sdata || !scan_req)
 920                 goto out;
 921
 922         if (!local->scanning) {
 923                 int rc;
 924
 925                 RCU_INIT_POINTER(local->scan_req, NULL);
 926                 RCU_INIT_POINTER(local->scan_sdata, NULL);
 927
 928                 rc = __ieee80211_start_scan(sdata, scan_req);
 929                 if (rc) {
 930                         /* need to complete scan in cfg80211 */
 931                         rcu_assign_pointer(local->scan_req, scan_req);
 932                         aborted = true;
 933                         goto out_complete;
 934                 } else
 935                         goto out;
 936         }
 937
 938         clear_bit(SCAN_BEACON_WAIT, &local->scanning);
 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                 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) &&
 951                     local->next_scan_state == SCAN_DECISION)
 952                         local->next_scan_state = SCAN_SEND_PROBE;
 953
 954                 switch (local->next_scan_state) {
 955                 case SCAN_DECISION:
 956                         /* if no more bands/channels left, complete scan */
 957                         if (local->scan_channel_idx >= scan_req->n_channels) {
 958                                 aborted = false;
 959                                 goto out_complete;
 960                         }
 961                         ieee80211_scan_state_decision(local, &next_delay);
 962                         break;
 963                 case SCAN_SET_CHANNEL:
 964                         ieee80211_scan_state_set_channel(local, &next_delay);
 965                         break;
 966                 case SCAN_SEND_PROBE:
 967                         ieee80211_scan_state_send_probe(local, &next_delay);
 968                         break;
 969                 case SCAN_SUSPEND:
 970                         ieee80211_scan_state_suspend(local, &next_delay);
 971                         break;
 972                 case SCAN_RESUME:
 973                         ieee80211_scan_state_resume(local, &next_delay);
 974                         break;
 975                 case SCAN_ABORT:
 976                         aborted = true;
 977                         goto out_complete;
 978                 }
 979         } while (next_delay == 0);
 980
 981         ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
 982         goto out;
 983
 984 out_complete:
 985         __ieee80211_scan_completed(&local->hw, aborted);
 986 out:
 987         mutex_unlock(&local->mtx);
 988 }
 989
 990 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
 991                            struct cfg80211_scan_request *req)
 992 {
 993         int res;
 994
 995         mutex_lock(&sdata->local->mtx);
 996         res = __ieee80211_start_scan(sdata, req);
 997         mutex_unlock(&sdata->local->mtx);
 998
 999         return res;
1000 }
1001
1002 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1003                                 const u8 *ssid, u8 ssid_len,
1004                                 struct ieee80211_channel **channels,
1005                                 unsigned int n_channels,
1006                                 enum nl80211_bss_scan_width scan_width)
1007 {
1008         struct ieee80211_local *local = sdata->local;
1009         int ret = -EBUSY, i, n_ch = 0;
1010         enum nl80211_band band;
1011
1012         mutex_lock(&local->mtx);
1013
1014         /* busy scanning */
1015         if (local->scan_req)
1016                 goto unlock;
1017
1018         /* fill internal scan request */
1019         if (!channels) {
1020                 int max_n;
1021
1022                 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1023                         if (!local->hw.wiphy->bands[band])
1024                                 continue;
1025
1026                         max_n = local->hw.wiphy->bands[band]->n_channels;
1027                         for (i = 0; i < max_n; i++) {
1028                                 struct ieee80211_channel *tmp_ch =
1029                                     &local->hw.wiphy->bands[band]->channels[i];
1030
1031                                 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1032                                                      IEEE80211_CHAN_DISABLED))
1033                                         continue;
1034
1035                                 local->int_scan_req->channels[n_ch] = tmp_ch;
1036                                 n_ch++;
1037                         }
1038                 }
1039
1040                 if (WARN_ON_ONCE(n_ch == 0))
1041                         goto unlock;
1042
1043                 local->int_scan_req->n_channels = n_ch;
1044         } else {
1045                 for (i = 0; i < n_channels; i++) {
1046                         if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1047                                                   IEEE80211_CHAN_DISABLED))
1048                                 continue;
1049
1050                         local->int_scan_req->channels[n_ch] = channels[i];
1051                         n_ch++;
1052                 }
1053
1054                 if (WARN_ON_ONCE(n_ch == 0))
1055                         goto unlock;
1056
1057                 local->int_scan_req->n_channels = n_ch;
1058         }
1059
1060         local->int_scan_req->ssids = &local->scan_ssid;
1061         local->int_scan_req->n_ssids = 1;
1062         local->int_scan_req->scan_width = scan_width;
1063         memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1064         local->int_scan_req->ssids[0].ssid_len = ssid_len;
1065
1066         ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1067  unlock:
1068         mutex_unlock(&local->mtx);
1069         return ret;
1070 }
1071
1072 /*
1073  * Only call this function when a scan can't be queued -- under RTNL.
1074  */
1075 void ieee80211_scan_cancel(struct ieee80211_local *local)
1076 {
1077         /*
1078          * We are canceling software scan, or deferred scan that was not
1079          * yet really started (see __ieee80211_start_scan ).
1080          *
1081          * Regarding hardware scan:
1082          * - we can not call  __ieee80211_scan_completed() as when
1083          *   SCAN_HW_SCANNING bit is set this function change
1084          *   local->hw_scan_req to operate on 5G band, what race with
1085          *   driver which can use local->hw_scan_req
1086          *
1087          * - we can not cancel scan_work since driver can schedule it
1088          *   by ieee80211_scan_completed(..., true) to finish scan
1089          *
1090          * Hence we only call the cancel_hw_scan() callback, but the low-level
1091          * driver is still responsible for calling ieee80211_scan_completed()
1092          * after the scan was completed/aborted.
1093          */
1094
1095         mutex_lock(&local->mtx);
1096         if (!local->scan_req)
1097                 goto out;
1098
1099         /*
1100          * We have a scan running and the driver already reported completion,
1101          * but the worker hasn't run yet or is stuck on the mutex - mark it as
1102          * cancelled.
1103          */
1104         if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1105             test_bit(SCAN_COMPLETED, &local->scanning)) {
1106                 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1107                 goto out;
1108         }
1109
1110         if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1111                 /*
1112                  * Make sure that __ieee80211_scan_completed doesn't trigger a
1113                  * scan on another band.
1114                  */
1115                 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1116                 if (local->ops->cancel_hw_scan)
1117                         drv_cancel_hw_scan(local,
1118                                 rcu_dereference_protected(local->scan_sdata,
1119                                                 lockdep_is_held(&local->mtx)));
1120                 goto out;
1121         }
1122
1123         /*
1124          * If the work is currently running, it must be blocked on
1125          * the mutex, but we'll set scan_sdata = NULL and it'll
1126          * simply exit once it acquires the mutex.
1127          */
1128         cancel_delayed_work(&local->scan_work);
1129         /* and clean up */
1130         memset(&local->scan_info, 0, sizeof(local->scan_info));
1131         __ieee80211_scan_completed(&local->hw, true);
1132 out:
1133         mutex_unlock(&local->mtx);
1134 }
1135
1136 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1137                                         struct cfg80211_sched_scan_request *req)
1138 {
1139         struct ieee80211_local *local = sdata->local;
1140         struct ieee80211_scan_ies sched_scan_ies = {};
1141         struct cfg80211_chan_def chandef;
1142         int ret, i, iebufsz, num_bands = 0;
1143         u32 rate_masks[NUM_NL80211_BANDS] = {};
1144         u8 bands_used = 0;
1145         u8 *ie;
1146
1147         iebufsz = local->scan_ies_len + req->ie_len;
1148
1149         lockdep_assert_held(&local->mtx);
1150
1151         if (!local->ops->sched_scan_start)
1152                 return -ENOTSUPP;
1153
1154         for (i = 0; i < NUM_NL80211_BANDS; i++) {
1155                 if (local->hw.wiphy->bands[i]) {
1156                         bands_used |= BIT(i);
1157                         rate_masks[i] = (u32) -1;
1158                         num_bands++;
1159                 }
1160         }
1161
1162         ie = kzalloc(num_bands * iebufsz, GFP_KERNEL);
1163         if (!ie) {
1164                 ret = -ENOMEM;
1165                 goto out;
1166         }
1167
1168         ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1169
1170         ieee80211_build_preq_ies(local, ie, num_bands * iebufsz,
1171                                  &sched_scan_ies, req->ie,
1172                                  req->ie_len, bands_used, rate_masks, &chandef);
1173
1174         ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1175         if (ret == 0) {
1176                 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1177                 rcu_assign_pointer(local->sched_scan_req, req);
1178         }
1179
1180         kfree(ie);
1181
1182 out:
1183         if (ret) {
1184                 /* Clean in case of failure after HW restart or upon resume. */
1185                 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1186                 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1187         }
1188
1189         return ret;
1190 }
1191
1192 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1193                                        struct cfg80211_sched_scan_request *req)
1194 {
1195         struct ieee80211_local *local = sdata->local;
1196         int ret;
1197
1198         mutex_lock(&local->mtx);
1199
1200         if (rcu_access_pointer(local->sched_scan_sdata)) {
1201                 mutex_unlock(&local->mtx);
1202                 return -EBUSY;
1203         }
1204
1205         ret = __ieee80211_request_sched_scan_start(sdata, req);
1206
1207         mutex_unlock(&local->mtx);
1208         return ret;
1209 }
1210
1211 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1212 {
1213         struct ieee80211_sub_if_data *sched_scan_sdata;
1214         int ret = -ENOENT;
1215
1216         mutex_lock(&local->mtx);
1217
1218         if (!local->ops->sched_scan_stop) {
1219                 ret = -ENOTSUPP;
1220                 goto out;
1221         }
1222
1223         /* We don't want to restart sched scan anymore. */
1224         RCU_INIT_POINTER(local->sched_scan_req, NULL);
1225
1226         sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1227                                                 lockdep_is_held(&local->mtx));
1228         if (sched_scan_sdata) {
1229                 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1230                 if (!ret)
1231                         RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1232         }
1233 out:
1234         mutex_unlock(&local->mtx);
1235
1236         return ret;
1237 }
1238
1239 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1240 {
1241         struct ieee80211_local *local = hw_to_local(hw);
1242
1243         trace_api_sched_scan_results(local);
1244
1245         cfg80211_sched_scan_results(hw->wiphy, 0);
1246 }
1247 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1248
1249 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1250 {
1251         mutex_lock(&local->mtx);
1252
1253         if (!rcu_access_pointer(local->sched_scan_sdata)) {
1254                 mutex_unlock(&local->mtx);
1255                 return;
1256         }
1257
1258         RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1259
1260         /* If sched scan was aborted by the driver. */
1261         RCU_INIT_POINTER(local->sched_scan_req, NULL);
1262
1263         mutex_unlock(&local->mtx);
1264
1265         cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1266 }
1267
1268 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1269 {
1270         struct ieee80211_local *local =
1271                 container_of(work, struct ieee80211_local,
1272                              sched_scan_stopped_work);
1273
1274         ieee80211_sched_scan_end(local);
1275 }
1276
1277 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1278 {
1279         struct ieee80211_local *local = hw_to_local(hw);
1280
1281         trace_api_sched_scan_stopped(local);
1282
1283         /*
1284          * this shouldn't really happen, so for simplicity
1285          * simply ignore it, and let mac80211 reconfigure
1286          * the sched scan later on.
1287          */
1288         if (local->in_reconfig)
1289                 return;
1290
1291         schedule_work(&local->sched_scan_stopped_work);
1292 }
1293 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);