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TOMOYO Linux Cross Reference
Linux/net/mac80211/scan.c

Version: ~ [ linux-5.4-rc3 ] ~ [ linux-5.3.6 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.79 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.149 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.196 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.196 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.75 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 2016-2017  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);
1290 

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