xref: /linux/net/mac80211/scan.c (revision bfd5bb6f90af092aa345b15cd78143956a13c2a8)
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 (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL)
77 		bss_meta.signal = 0; /* invalid signal indication */
78 	else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
79 		bss_meta.signal = rx_status->signal * 100;
80 	else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
81 		bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
82 
83 	bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20;
84 	if (rx_status->bw == RATE_INFO_BW_5)
85 		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5;
86 	else if (rx_status->bw == RATE_INFO_BW_10)
87 		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10;
88 
89 	bss_meta.chan = channel;
90 
91 	rcu_read_lock();
92 	scan_sdata = rcu_dereference(local->scan_sdata);
93 	if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
94 	    scan_sdata->vif.bss_conf.assoc &&
95 	    ieee80211_have_rx_timestamp(rx_status)) {
96 		bss_meta.parent_tsf =
97 			ieee80211_calculate_rx_timestamp(local, rx_status,
98 							 len + FCS_LEN, 24);
99 		ether_addr_copy(bss_meta.parent_bssid,
100 				scan_sdata->vif.bss_conf.bssid);
101 	}
102 	rcu_read_unlock();
103 
104 	cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
105 					      mgmt, len, GFP_ATOMIC);
106 	if (!cbss)
107 		return NULL;
108 	/* In case the signal is invalid update the status */
109 	signal_valid = abs(channel->center_freq - cbss->channel->center_freq)
110 		<= local->hw.wiphy->max_adj_channel_rssi_comp;
111 	if (!signal_valid)
112 		rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
113 
114 	bss = (void *)cbss->priv;
115 
116 	if (beacon)
117 		bss->device_ts_beacon = rx_status->device_timestamp;
118 	else
119 		bss->device_ts_presp = rx_status->device_timestamp;
120 
121 	if (elems->parse_error) {
122 		if (beacon)
123 			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
124 		else
125 			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
126 	} else {
127 		if (beacon)
128 			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
129 		else
130 			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
131 	}
132 
133 	/* save the ERP value so that it is available at association time */
134 	if (elems->erp_info && (!elems->parse_error ||
135 				!(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
136 		bss->erp_value = elems->erp_info[0];
137 		bss->has_erp_value = true;
138 		if (!elems->parse_error)
139 			bss->valid_data |= IEEE80211_BSS_VALID_ERP;
140 	}
141 
142 	/* replace old supported rates if we get new values */
143 	if (!elems->parse_error ||
144 	    !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
145 		srlen = 0;
146 		if (elems->supp_rates) {
147 			clen = IEEE80211_MAX_SUPP_RATES;
148 			if (clen > elems->supp_rates_len)
149 				clen = elems->supp_rates_len;
150 			memcpy(bss->supp_rates, elems->supp_rates, clen);
151 			srlen += clen;
152 		}
153 		if (elems->ext_supp_rates) {
154 			clen = IEEE80211_MAX_SUPP_RATES - srlen;
155 			if (clen > elems->ext_supp_rates_len)
156 				clen = elems->ext_supp_rates_len;
157 			memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
158 			       clen);
159 			srlen += clen;
160 		}
161 		if (srlen) {
162 			bss->supp_rates_len = srlen;
163 			if (!elems->parse_error)
164 				bss->valid_data |= IEEE80211_BSS_VALID_RATES;
165 		}
166 	}
167 
168 	if (!elems->parse_error ||
169 	    !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
170 		bss->wmm_used = elems->wmm_param || elems->wmm_info;
171 		bss->uapsd_supported = is_uapsd_supported(elems);
172 		if (!elems->parse_error)
173 			bss->valid_data |= IEEE80211_BSS_VALID_WMM;
174 	}
175 
176 	if (beacon) {
177 		struct ieee80211_supported_band *sband =
178 			local->hw.wiphy->bands[rx_status->band];
179 		if (!(rx_status->encoding == RX_ENC_HT) &&
180 		    !(rx_status->encoding == RX_ENC_VHT))
181 			bss->beacon_rate =
182 				&sband->bitrates[rx_status->rate_idx];
183 	}
184 
185 	return bss;
186 }
187 
188 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
189 					u32 scan_flags, const u8 *da)
190 {
191 	if (!sdata)
192 		return false;
193 	/* accept broadcast for OCE */
194 	if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
195 	    is_broadcast_ether_addr(da))
196 		return true;
197 	if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
198 		return true;
199 	return ether_addr_equal(da, sdata->vif.addr);
200 }
201 
202 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
203 {
204 	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
205 	struct ieee80211_sub_if_data *sdata1, *sdata2;
206 	struct ieee80211_mgmt *mgmt = (void *)skb->data;
207 	struct ieee80211_bss *bss;
208 	u8 *elements;
209 	struct ieee80211_channel *channel;
210 	size_t baselen;
211 	struct ieee802_11_elems elems;
212 
213 	if (skb->len < 24 ||
214 	    (!ieee80211_is_probe_resp(mgmt->frame_control) &&
215 	     !ieee80211_is_beacon(mgmt->frame_control)))
216 		return;
217 
218 	sdata1 = rcu_dereference(local->scan_sdata);
219 	sdata2 = rcu_dereference(local->sched_scan_sdata);
220 
221 	if (likely(!sdata1 && !sdata2))
222 		return;
223 
224 	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
225 		struct cfg80211_scan_request *scan_req;
226 		struct cfg80211_sched_scan_request *sched_scan_req;
227 		u32 scan_req_flags = 0, sched_scan_req_flags = 0;
228 
229 		scan_req = rcu_dereference(local->scan_req);
230 		sched_scan_req = rcu_dereference(local->sched_scan_req);
231 
232 		if (scan_req)
233 			scan_req_flags = scan_req->flags;
234 
235 		if (sched_scan_req)
236 			sched_scan_req_flags = sched_scan_req->flags;
237 
238 		/* ignore ProbeResp to foreign address or non-bcast (OCE)
239 		 * unless scanning with randomised address
240 		 */
241 		if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
242 						 mgmt->da) &&
243 		    !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
244 						 mgmt->da))
245 			return;
246 
247 		elements = mgmt->u.probe_resp.variable;
248 		baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
249 	} else {
250 		baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
251 		elements = mgmt->u.beacon.variable;
252 	}
253 
254 	if (baselen > skb->len)
255 		return;
256 
257 	ieee802_11_parse_elems(elements, skb->len - baselen, false, &elems);
258 
259 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
260 
261 	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
262 		return;
263 
264 	bss = ieee80211_bss_info_update(local, rx_status,
265 					mgmt, skb->len, &elems,
266 					channel);
267 	if (bss)
268 		ieee80211_rx_bss_put(local, bss);
269 }
270 
271 static void
272 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
273 			       enum nl80211_bss_scan_width scan_width)
274 {
275 	memset(chandef, 0, sizeof(*chandef));
276 	switch (scan_width) {
277 	case NL80211_BSS_CHAN_WIDTH_5:
278 		chandef->width = NL80211_CHAN_WIDTH_5;
279 		break;
280 	case NL80211_BSS_CHAN_WIDTH_10:
281 		chandef->width = NL80211_CHAN_WIDTH_10;
282 		break;
283 	default:
284 		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
285 		break;
286 	}
287 }
288 
289 /* return false if no more work */
290 static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
291 {
292 	struct cfg80211_scan_request *req;
293 	struct cfg80211_chan_def chandef;
294 	u8 bands_used = 0;
295 	int i, ielen, n_chans;
296 
297 	req = rcu_dereference_protected(local->scan_req,
298 					lockdep_is_held(&local->mtx));
299 
300 	if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
301 		return false;
302 
303 	if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
304 		for (i = 0; i < req->n_channels; i++) {
305 			local->hw_scan_req->req.channels[i] = req->channels[i];
306 			bands_used |= BIT(req->channels[i]->band);
307 		}
308 
309 		n_chans = req->n_channels;
310 	} else {
311 		do {
312 			if (local->hw_scan_band == NUM_NL80211_BANDS)
313 				return false;
314 
315 			n_chans = 0;
316 
317 			for (i = 0; i < req->n_channels; i++) {
318 				if (req->channels[i]->band !=
319 				    local->hw_scan_band)
320 					continue;
321 				local->hw_scan_req->req.channels[n_chans] =
322 							req->channels[i];
323 				n_chans++;
324 				bands_used |= BIT(req->channels[i]->band);
325 			}
326 
327 			local->hw_scan_band++;
328 		} while (!n_chans);
329 	}
330 
331 	local->hw_scan_req->req.n_channels = n_chans;
332 	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
333 
334 	ielen = ieee80211_build_preq_ies(local,
335 					 (u8 *)local->hw_scan_req->req.ie,
336 					 local->hw_scan_ies_bufsize,
337 					 &local->hw_scan_req->ies,
338 					 req->ie, req->ie_len,
339 					 bands_used, req->rates, &chandef);
340 	local->hw_scan_req->req.ie_len = ielen;
341 	local->hw_scan_req->req.no_cck = req->no_cck;
342 	ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
343 	ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
344 			req->mac_addr_mask);
345 	ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
346 
347 	return true;
348 }
349 
350 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
351 {
352 	struct ieee80211_local *local = hw_to_local(hw);
353 	bool hw_scan = local->ops->hw_scan;
354 	bool was_scanning = local->scanning;
355 	struct cfg80211_scan_request *scan_req;
356 	struct ieee80211_sub_if_data *scan_sdata;
357 	struct ieee80211_sub_if_data *sdata;
358 
359 	lockdep_assert_held(&local->mtx);
360 
361 	/*
362 	 * It's ok to abort a not-yet-running scan (that
363 	 * we have one at all will be verified by checking
364 	 * local->scan_req next), but not to complete it
365 	 * successfully.
366 	 */
367 	if (WARN_ON(!local->scanning && !aborted))
368 		aborted = true;
369 
370 	if (WARN_ON(!local->scan_req))
371 		return;
372 
373 	if (hw_scan && !aborted &&
374 	    !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
375 	    ieee80211_prep_hw_scan(local)) {
376 		int rc;
377 
378 		rc = drv_hw_scan(local,
379 			rcu_dereference_protected(local->scan_sdata,
380 						  lockdep_is_held(&local->mtx)),
381 			local->hw_scan_req);
382 
383 		if (rc == 0)
384 			return;
385 
386 		/* HW scan failed and is going to be reported as aborted,
387 		 * so clear old scan info.
388 		 */
389 		memset(&local->scan_info, 0, sizeof(local->scan_info));
390 		aborted = true;
391 	}
392 
393 	kfree(local->hw_scan_req);
394 	local->hw_scan_req = NULL;
395 
396 	scan_req = rcu_dereference_protected(local->scan_req,
397 					     lockdep_is_held(&local->mtx));
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 	RCU_INIT_POINTER(local->scan_req, NULL);
404 
405 	scan_sdata = rcu_dereference_protected(local->scan_sdata,
406 					       lockdep_is_held(&local->mtx));
407 	RCU_INIT_POINTER(local->scan_sdata, NULL);
408 
409 	local->scanning = 0;
410 	local->scan_chandef.chan = NULL;
411 
412 	/* Set power back to normal operating levels. */
413 	ieee80211_hw_config(local, 0);
414 
415 	if (!hw_scan) {
416 		ieee80211_configure_filter(local);
417 		drv_sw_scan_complete(local, scan_sdata);
418 		ieee80211_offchannel_return(local);
419 	}
420 
421 	ieee80211_recalc_idle(local);
422 
423 	ieee80211_mlme_notify_scan_completed(local);
424 	ieee80211_ibss_notify_scan_completed(local);
425 
426 	/* Requeue all the work that might have been ignored while
427 	 * the scan was in progress; if there was none this will
428 	 * just be a no-op for the particular interface.
429 	 */
430 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
431 		if (ieee80211_sdata_running(sdata))
432 			ieee80211_queue_work(&sdata->local->hw, &sdata->work);
433 	}
434 
435 	if (was_scanning)
436 		ieee80211_start_next_roc(local);
437 }
438 
439 void ieee80211_scan_completed(struct ieee80211_hw *hw,
440 			      struct cfg80211_scan_info *info)
441 {
442 	struct ieee80211_local *local = hw_to_local(hw);
443 
444 	trace_api_scan_completed(local, info->aborted);
445 
446 	set_bit(SCAN_COMPLETED, &local->scanning);
447 	if (info->aborted)
448 		set_bit(SCAN_ABORTED, &local->scanning);
449 
450 	memcpy(&local->scan_info, info, sizeof(*info));
451 
452 	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
453 }
454 EXPORT_SYMBOL(ieee80211_scan_completed);
455 
456 static int ieee80211_start_sw_scan(struct ieee80211_local *local,
457 				   struct ieee80211_sub_if_data *sdata)
458 {
459 	/* Software scan is not supported in multi-channel cases */
460 	if (local->use_chanctx)
461 		return -EOPNOTSUPP;
462 
463 	/*
464 	 * Hardware/driver doesn't support hw_scan, so use software
465 	 * scanning instead. First send a nullfunc frame with power save
466 	 * bit on so that AP will buffer the frames for us while we are not
467 	 * listening, then send probe requests to each channel and wait for
468 	 * the responses. After all channels are scanned, tune back to the
469 	 * original channel and send a nullfunc frame with power save bit
470 	 * off to trigger the AP to send us all the buffered frames.
471 	 *
472 	 * Note that while local->sw_scanning is true everything else but
473 	 * nullfunc frames and probe requests will be dropped in
474 	 * ieee80211_tx_h_check_assoc().
475 	 */
476 	drv_sw_scan_start(local, sdata, local->scan_addr);
477 
478 	local->leave_oper_channel_time = jiffies;
479 	local->next_scan_state = SCAN_DECISION;
480 	local->scan_channel_idx = 0;
481 
482 	ieee80211_offchannel_stop_vifs(local);
483 
484 	/* ensure nullfunc is transmitted before leaving operating channel */
485 	ieee80211_flush_queues(local, NULL, false);
486 
487 	ieee80211_configure_filter(local);
488 
489 	/* We need to set power level at maximum rate for scanning. */
490 	ieee80211_hw_config(local, 0);
491 
492 	ieee80211_queue_delayed_work(&local->hw,
493 				     &local->scan_work, 0);
494 
495 	return 0;
496 }
497 
498 static bool ieee80211_can_scan(struct ieee80211_local *local,
499 			       struct ieee80211_sub_if_data *sdata)
500 {
501 	if (ieee80211_is_radar_required(local))
502 		return false;
503 
504 	if (!list_empty(&local->roc_list))
505 		return false;
506 
507 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
508 	    sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
509 		return false;
510 
511 	return true;
512 }
513 
514 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
515 {
516 	lockdep_assert_held(&local->mtx);
517 
518 	if (!local->scan_req || local->scanning)
519 		return;
520 
521 	if (!ieee80211_can_scan(local,
522 				rcu_dereference_protected(
523 					local->scan_sdata,
524 					lockdep_is_held(&local->mtx))))
525 		return;
526 
527 	ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
528 				     round_jiffies_relative(0));
529 }
530 
531 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
532 					    unsigned long *next_delay)
533 {
534 	int i;
535 	struct ieee80211_sub_if_data *sdata;
536 	struct cfg80211_scan_request *scan_req;
537 	enum nl80211_band band = local->hw.conf.chandef.chan->band;
538 	u32 tx_flags;
539 
540 	scan_req = rcu_dereference_protected(local->scan_req,
541 					     lockdep_is_held(&local->mtx));
542 
543 	tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
544 	if (scan_req->no_cck)
545 		tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
546 
547 	sdata = rcu_dereference_protected(local->scan_sdata,
548 					  lockdep_is_held(&local->mtx));
549 
550 	for (i = 0; i < scan_req->n_ssids; i++)
551 		ieee80211_send_probe_req(
552 			sdata, local->scan_addr, scan_req->bssid,
553 			scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
554 			scan_req->ie, scan_req->ie_len,
555 			scan_req->rates[band], false,
556 			tx_flags, local->hw.conf.chandef.chan, true);
557 
558 	/*
559 	 * After sending probe requests, wait for probe responses
560 	 * on the channel.
561 	 */
562 	*next_delay = IEEE80211_CHANNEL_TIME;
563 	local->next_scan_state = SCAN_DECISION;
564 }
565 
566 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
567 				  struct cfg80211_scan_request *req)
568 {
569 	struct ieee80211_local *local = sdata->local;
570 	int rc;
571 
572 	lockdep_assert_held(&local->mtx);
573 
574 	if (local->scan_req || ieee80211_is_radar_required(local))
575 		return -EBUSY;
576 
577 	if (!ieee80211_can_scan(local, sdata)) {
578 		/* wait for the work to finish/time out */
579 		rcu_assign_pointer(local->scan_req, req);
580 		rcu_assign_pointer(local->scan_sdata, sdata);
581 		return 0;
582 	}
583 
584 	if (local->ops->hw_scan) {
585 		u8 *ies;
586 
587 		local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
588 
589 		if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
590 			int i, n_bands = 0;
591 			u8 bands_counted = 0;
592 
593 			for (i = 0; i < req->n_channels; i++) {
594 				if (bands_counted & BIT(req->channels[i]->band))
595 					continue;
596 				bands_counted |= BIT(req->channels[i]->band);
597 				n_bands++;
598 			}
599 
600 			local->hw_scan_ies_bufsize *= n_bands;
601 		}
602 
603 		local->hw_scan_req = kmalloc(
604 				sizeof(*local->hw_scan_req) +
605 				req->n_channels * sizeof(req->channels[0]) +
606 				local->hw_scan_ies_bufsize, GFP_KERNEL);
607 		if (!local->hw_scan_req)
608 			return -ENOMEM;
609 
610 		local->hw_scan_req->req.ssids = req->ssids;
611 		local->hw_scan_req->req.n_ssids = req->n_ssids;
612 		ies = (u8 *)local->hw_scan_req +
613 			sizeof(*local->hw_scan_req) +
614 			req->n_channels * sizeof(req->channels[0]);
615 		local->hw_scan_req->req.ie = ies;
616 		local->hw_scan_req->req.flags = req->flags;
617 		eth_broadcast_addr(local->hw_scan_req->req.bssid);
618 		local->hw_scan_req->req.duration = req->duration;
619 		local->hw_scan_req->req.duration_mandatory =
620 			req->duration_mandatory;
621 
622 		local->hw_scan_band = 0;
623 
624 		/*
625 		 * After allocating local->hw_scan_req, we must
626 		 * go through until ieee80211_prep_hw_scan(), so
627 		 * anything that might be changed here and leave
628 		 * this function early must not go after this
629 		 * allocation.
630 		 */
631 	}
632 
633 	rcu_assign_pointer(local->scan_req, req);
634 	rcu_assign_pointer(local->scan_sdata, sdata);
635 
636 	if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
637 		get_random_mask_addr(local->scan_addr,
638 				     req->mac_addr,
639 				     req->mac_addr_mask);
640 	else
641 		memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
642 
643 	if (local->ops->hw_scan) {
644 		__set_bit(SCAN_HW_SCANNING, &local->scanning);
645 	} else if ((req->n_channels == 1) &&
646 		   (req->channels[0] == local->_oper_chandef.chan)) {
647 		/*
648 		 * If we are scanning only on the operating channel
649 		 * then we do not need to stop normal activities
650 		 */
651 		unsigned long next_delay;
652 
653 		__set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
654 
655 		ieee80211_recalc_idle(local);
656 
657 		/* Notify driver scan is starting, keep order of operations
658 		 * same as normal software scan, in case that matters. */
659 		drv_sw_scan_start(local, sdata, local->scan_addr);
660 
661 		ieee80211_configure_filter(local); /* accept probe-responses */
662 
663 		/* We need to ensure power level is at max for scanning. */
664 		ieee80211_hw_config(local, 0);
665 
666 		if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
667 						IEEE80211_CHAN_RADAR)) ||
668 		    !req->n_ssids) {
669 			next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
670 		} else {
671 			ieee80211_scan_state_send_probe(local, &next_delay);
672 			next_delay = IEEE80211_CHANNEL_TIME;
673 		}
674 
675 		/* Now, just wait a bit and we are all done! */
676 		ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
677 					     next_delay);
678 		return 0;
679 	} else {
680 		/* Do normal software scan */
681 		__set_bit(SCAN_SW_SCANNING, &local->scanning);
682 	}
683 
684 	ieee80211_recalc_idle(local);
685 
686 	if (local->ops->hw_scan) {
687 		WARN_ON(!ieee80211_prep_hw_scan(local));
688 		rc = drv_hw_scan(local, sdata, local->hw_scan_req);
689 	} else {
690 		rc = ieee80211_start_sw_scan(local, sdata);
691 	}
692 
693 	if (rc) {
694 		kfree(local->hw_scan_req);
695 		local->hw_scan_req = NULL;
696 		local->scanning = 0;
697 
698 		ieee80211_recalc_idle(local);
699 
700 		local->scan_req = NULL;
701 		RCU_INIT_POINTER(local->scan_sdata, NULL);
702 	}
703 
704 	return rc;
705 }
706 
707 static unsigned long
708 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
709 {
710 	/*
711 	 * TODO: channel switching also consumes quite some time,
712 	 * add that delay as well to get a better estimation
713 	 */
714 	if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
715 		return IEEE80211_PASSIVE_CHANNEL_TIME;
716 	return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
717 }
718 
719 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
720 					  unsigned long *next_delay)
721 {
722 	bool associated = false;
723 	bool tx_empty = true;
724 	bool bad_latency;
725 	struct ieee80211_sub_if_data *sdata;
726 	struct ieee80211_channel *next_chan;
727 	enum mac80211_scan_state next_scan_state;
728 	struct cfg80211_scan_request *scan_req;
729 
730 	/*
731 	 * check if at least one STA interface is associated,
732 	 * check if at least one STA interface has pending tx frames
733 	 * and grab the lowest used beacon interval
734 	 */
735 	mutex_lock(&local->iflist_mtx);
736 	list_for_each_entry(sdata, &local->interfaces, list) {
737 		if (!ieee80211_sdata_running(sdata))
738 			continue;
739 
740 		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
741 			if (sdata->u.mgd.associated) {
742 				associated = true;
743 
744 				if (!qdisc_all_tx_empty(sdata->dev)) {
745 					tx_empty = false;
746 					break;
747 				}
748 			}
749 		}
750 	}
751 	mutex_unlock(&local->iflist_mtx);
752 
753 	scan_req = rcu_dereference_protected(local->scan_req,
754 					     lockdep_is_held(&local->mtx));
755 
756 	next_chan = scan_req->channels[local->scan_channel_idx];
757 
758 	/*
759 	 * we're currently scanning a different channel, let's
760 	 * see if we can scan another channel without interfering
761 	 * with the current traffic situation.
762 	 *
763 	 * Keep good latency, do not stay off-channel more than 125 ms.
764 	 */
765 
766 	bad_latency = time_after(jiffies +
767 				 ieee80211_scan_get_channel_time(next_chan),
768 				 local->leave_oper_channel_time + HZ / 8);
769 
770 	if (associated && !tx_empty) {
771 		if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
772 			next_scan_state = SCAN_ABORT;
773 		else
774 			next_scan_state = SCAN_SUSPEND;
775 	} else if (associated && bad_latency) {
776 		next_scan_state = SCAN_SUSPEND;
777 	} else {
778 		next_scan_state = SCAN_SET_CHANNEL;
779 	}
780 
781 	local->next_scan_state = next_scan_state;
782 
783 	*next_delay = 0;
784 }
785 
786 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
787 					     unsigned long *next_delay)
788 {
789 	int skip;
790 	struct ieee80211_channel *chan;
791 	enum nl80211_bss_scan_width oper_scan_width;
792 	struct cfg80211_scan_request *scan_req;
793 
794 	scan_req = rcu_dereference_protected(local->scan_req,
795 					     lockdep_is_held(&local->mtx));
796 
797 	skip = 0;
798 	chan = scan_req->channels[local->scan_channel_idx];
799 
800 	local->scan_chandef.chan = chan;
801 	local->scan_chandef.center_freq1 = chan->center_freq;
802 	local->scan_chandef.center_freq2 = 0;
803 	switch (scan_req->scan_width) {
804 	case NL80211_BSS_CHAN_WIDTH_5:
805 		local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
806 		break;
807 	case NL80211_BSS_CHAN_WIDTH_10:
808 		local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
809 		break;
810 	case NL80211_BSS_CHAN_WIDTH_20:
811 		/* If scanning on oper channel, use whatever channel-type
812 		 * is currently in use.
813 		 */
814 		oper_scan_width = cfg80211_chandef_to_scan_width(
815 					&local->_oper_chandef);
816 		if (chan == local->_oper_chandef.chan &&
817 		    oper_scan_width == scan_req->scan_width)
818 			local->scan_chandef = local->_oper_chandef;
819 		else
820 			local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
821 		break;
822 	}
823 
824 	if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
825 		skip = 1;
826 
827 	/* advance state machine to next channel/band */
828 	local->scan_channel_idx++;
829 
830 	if (skip) {
831 		/* if we skip this channel return to the decision state */
832 		local->next_scan_state = SCAN_DECISION;
833 		return;
834 	}
835 
836 	/*
837 	 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
838 	 * (which unfortunately doesn't say _why_ step a) is done,
839 	 * but it waits for the probe delay or until a frame is
840 	 * received - and the received frame would update the NAV).
841 	 * For now, we do not support waiting until a frame is
842 	 * received.
843 	 *
844 	 * In any case, it is not necessary for a passive scan.
845 	 */
846 	if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
847 	    !scan_req->n_ssids) {
848 		*next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
849 		local->next_scan_state = SCAN_DECISION;
850 		return;
851 	}
852 
853 	/* active scan, send probes */
854 	*next_delay = IEEE80211_PROBE_DELAY;
855 	local->next_scan_state = SCAN_SEND_PROBE;
856 }
857 
858 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
859 					 unsigned long *next_delay)
860 {
861 	/* switch back to the operating channel */
862 	local->scan_chandef.chan = NULL;
863 	ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
864 
865 	/* disable PS */
866 	ieee80211_offchannel_return(local);
867 
868 	*next_delay = HZ / 5;
869 	/* afterwards, resume scan & go to next channel */
870 	local->next_scan_state = SCAN_RESUME;
871 }
872 
873 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
874 					unsigned long *next_delay)
875 {
876 	ieee80211_offchannel_stop_vifs(local);
877 
878 	if (local->ops->flush) {
879 		ieee80211_flush_queues(local, NULL, false);
880 		*next_delay = 0;
881 	} else
882 		*next_delay = HZ / 10;
883 
884 	/* remember when we left the operating channel */
885 	local->leave_oper_channel_time = jiffies;
886 
887 	/* advance to the next channel to be scanned */
888 	local->next_scan_state = SCAN_SET_CHANNEL;
889 }
890 
891 void ieee80211_scan_work(struct work_struct *work)
892 {
893 	struct ieee80211_local *local =
894 		container_of(work, struct ieee80211_local, scan_work.work);
895 	struct ieee80211_sub_if_data *sdata;
896 	struct cfg80211_scan_request *scan_req;
897 	unsigned long next_delay = 0;
898 	bool aborted;
899 
900 	mutex_lock(&local->mtx);
901 
902 	if (!ieee80211_can_run_worker(local)) {
903 		aborted = true;
904 		goto out_complete;
905 	}
906 
907 	sdata = rcu_dereference_protected(local->scan_sdata,
908 					  lockdep_is_held(&local->mtx));
909 	scan_req = rcu_dereference_protected(local->scan_req,
910 					     lockdep_is_held(&local->mtx));
911 
912 	/* When scanning on-channel, the first-callback means completed. */
913 	if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
914 		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
915 		goto out_complete;
916 	}
917 
918 	if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
919 		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
920 		goto out_complete;
921 	}
922 
923 	if (!sdata || !scan_req)
924 		goto out;
925 
926 	if (!local->scanning) {
927 		int rc;
928 
929 		RCU_INIT_POINTER(local->scan_req, NULL);
930 		RCU_INIT_POINTER(local->scan_sdata, NULL);
931 
932 		rc = __ieee80211_start_scan(sdata, scan_req);
933 		if (rc) {
934 			/* need to complete scan in cfg80211 */
935 			rcu_assign_pointer(local->scan_req, scan_req);
936 			aborted = true;
937 			goto out_complete;
938 		} else
939 			goto out;
940 	}
941 
942 	/*
943 	 * as long as no delay is required advance immediately
944 	 * without scheduling a new work
945 	 */
946 	do {
947 		if (!ieee80211_sdata_running(sdata)) {
948 			aborted = true;
949 			goto out_complete;
950 		}
951 
952 		switch (local->next_scan_state) {
953 		case SCAN_DECISION:
954 			/* if no more bands/channels left, complete scan */
955 			if (local->scan_channel_idx >= scan_req->n_channels) {
956 				aborted = false;
957 				goto out_complete;
958 			}
959 			ieee80211_scan_state_decision(local, &next_delay);
960 			break;
961 		case SCAN_SET_CHANNEL:
962 			ieee80211_scan_state_set_channel(local, &next_delay);
963 			break;
964 		case SCAN_SEND_PROBE:
965 			ieee80211_scan_state_send_probe(local, &next_delay);
966 			break;
967 		case SCAN_SUSPEND:
968 			ieee80211_scan_state_suspend(local, &next_delay);
969 			break;
970 		case SCAN_RESUME:
971 			ieee80211_scan_state_resume(local, &next_delay);
972 			break;
973 		case SCAN_ABORT:
974 			aborted = true;
975 			goto out_complete;
976 		}
977 	} while (next_delay == 0);
978 
979 	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
980 	goto out;
981 
982 out_complete:
983 	__ieee80211_scan_completed(&local->hw, aborted);
984 out:
985 	mutex_unlock(&local->mtx);
986 }
987 
988 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
989 			   struct cfg80211_scan_request *req)
990 {
991 	int res;
992 
993 	mutex_lock(&sdata->local->mtx);
994 	res = __ieee80211_start_scan(sdata, req);
995 	mutex_unlock(&sdata->local->mtx);
996 
997 	return res;
998 }
999 
1000 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1001 				const u8 *ssid, u8 ssid_len,
1002 				struct ieee80211_channel **channels,
1003 				unsigned int n_channels,
1004 				enum nl80211_bss_scan_width scan_width)
1005 {
1006 	struct ieee80211_local *local = sdata->local;
1007 	int ret = -EBUSY, i, n_ch = 0;
1008 	enum nl80211_band band;
1009 
1010 	mutex_lock(&local->mtx);
1011 
1012 	/* busy scanning */
1013 	if (local->scan_req)
1014 		goto unlock;
1015 
1016 	/* fill internal scan request */
1017 	if (!channels) {
1018 		int max_n;
1019 
1020 		for (band = 0; band < NUM_NL80211_BANDS; band++) {
1021 			if (!local->hw.wiphy->bands[band])
1022 				continue;
1023 
1024 			max_n = local->hw.wiphy->bands[band]->n_channels;
1025 			for (i = 0; i < max_n; i++) {
1026 				struct ieee80211_channel *tmp_ch =
1027 				    &local->hw.wiphy->bands[band]->channels[i];
1028 
1029 				if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1030 						     IEEE80211_CHAN_DISABLED))
1031 					continue;
1032 
1033 				local->int_scan_req->channels[n_ch] = tmp_ch;
1034 				n_ch++;
1035 			}
1036 		}
1037 
1038 		if (WARN_ON_ONCE(n_ch == 0))
1039 			goto unlock;
1040 
1041 		local->int_scan_req->n_channels = n_ch;
1042 	} else {
1043 		for (i = 0; i < n_channels; i++) {
1044 			if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1045 						  IEEE80211_CHAN_DISABLED))
1046 				continue;
1047 
1048 			local->int_scan_req->channels[n_ch] = channels[i];
1049 			n_ch++;
1050 		}
1051 
1052 		if (WARN_ON_ONCE(n_ch == 0))
1053 			goto unlock;
1054 
1055 		local->int_scan_req->n_channels = n_ch;
1056 	}
1057 
1058 	local->int_scan_req->ssids = &local->scan_ssid;
1059 	local->int_scan_req->n_ssids = 1;
1060 	local->int_scan_req->scan_width = scan_width;
1061 	memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1062 	local->int_scan_req->ssids[0].ssid_len = ssid_len;
1063 
1064 	ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1065  unlock:
1066 	mutex_unlock(&local->mtx);
1067 	return ret;
1068 }
1069 
1070 /*
1071  * Only call this function when a scan can't be queued -- under RTNL.
1072  */
1073 void ieee80211_scan_cancel(struct ieee80211_local *local)
1074 {
1075 	/*
1076 	 * We are canceling software scan, or deferred scan that was not
1077 	 * yet really started (see __ieee80211_start_scan ).
1078 	 *
1079 	 * Regarding hardware scan:
1080 	 * - we can not call  __ieee80211_scan_completed() as when
1081 	 *   SCAN_HW_SCANNING bit is set this function change
1082 	 *   local->hw_scan_req to operate on 5G band, what race with
1083 	 *   driver which can use local->hw_scan_req
1084 	 *
1085 	 * - we can not cancel scan_work since driver can schedule it
1086 	 *   by ieee80211_scan_completed(..., true) to finish scan
1087 	 *
1088 	 * Hence we only call the cancel_hw_scan() callback, but the low-level
1089 	 * driver is still responsible for calling ieee80211_scan_completed()
1090 	 * after the scan was completed/aborted.
1091 	 */
1092 
1093 	mutex_lock(&local->mtx);
1094 	if (!local->scan_req)
1095 		goto out;
1096 
1097 	/*
1098 	 * We have a scan running and the driver already reported completion,
1099 	 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1100 	 * cancelled.
1101 	 */
1102 	if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1103 	    test_bit(SCAN_COMPLETED, &local->scanning)) {
1104 		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1105 		goto out;
1106 	}
1107 
1108 	if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1109 		/*
1110 		 * Make sure that __ieee80211_scan_completed doesn't trigger a
1111 		 * scan on another band.
1112 		 */
1113 		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1114 		if (local->ops->cancel_hw_scan)
1115 			drv_cancel_hw_scan(local,
1116 				rcu_dereference_protected(local->scan_sdata,
1117 						lockdep_is_held(&local->mtx)));
1118 		goto out;
1119 	}
1120 
1121 	/*
1122 	 * If the work is currently running, it must be blocked on
1123 	 * the mutex, but we'll set scan_sdata = NULL and it'll
1124 	 * simply exit once it acquires the mutex.
1125 	 */
1126 	cancel_delayed_work(&local->scan_work);
1127 	/* and clean up */
1128 	memset(&local->scan_info, 0, sizeof(local->scan_info));
1129 	__ieee80211_scan_completed(&local->hw, true);
1130 out:
1131 	mutex_unlock(&local->mtx);
1132 }
1133 
1134 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1135 					struct cfg80211_sched_scan_request *req)
1136 {
1137 	struct ieee80211_local *local = sdata->local;
1138 	struct ieee80211_scan_ies sched_scan_ies = {};
1139 	struct cfg80211_chan_def chandef;
1140 	int ret, i, iebufsz, num_bands = 0;
1141 	u32 rate_masks[NUM_NL80211_BANDS] = {};
1142 	u8 bands_used = 0;
1143 	u8 *ie;
1144 
1145 	iebufsz = local->scan_ies_len + req->ie_len;
1146 
1147 	lockdep_assert_held(&local->mtx);
1148 
1149 	if (!local->ops->sched_scan_start)
1150 		return -ENOTSUPP;
1151 
1152 	for (i = 0; i < NUM_NL80211_BANDS; i++) {
1153 		if (local->hw.wiphy->bands[i]) {
1154 			bands_used |= BIT(i);
1155 			rate_masks[i] = (u32) -1;
1156 			num_bands++;
1157 		}
1158 	}
1159 
1160 	ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1161 	if (!ie) {
1162 		ret = -ENOMEM;
1163 		goto out;
1164 	}
1165 
1166 	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1167 
1168 	ieee80211_build_preq_ies(local, ie, num_bands * iebufsz,
1169 				 &sched_scan_ies, req->ie,
1170 				 req->ie_len, bands_used, rate_masks, &chandef);
1171 
1172 	ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1173 	if (ret == 0) {
1174 		rcu_assign_pointer(local->sched_scan_sdata, sdata);
1175 		rcu_assign_pointer(local->sched_scan_req, req);
1176 	}
1177 
1178 	kfree(ie);
1179 
1180 out:
1181 	if (ret) {
1182 		/* Clean in case of failure after HW restart or upon resume. */
1183 		RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1184 		RCU_INIT_POINTER(local->sched_scan_req, NULL);
1185 	}
1186 
1187 	return ret;
1188 }
1189 
1190 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1191 				       struct cfg80211_sched_scan_request *req)
1192 {
1193 	struct ieee80211_local *local = sdata->local;
1194 	int ret;
1195 
1196 	mutex_lock(&local->mtx);
1197 
1198 	if (rcu_access_pointer(local->sched_scan_sdata)) {
1199 		mutex_unlock(&local->mtx);
1200 		return -EBUSY;
1201 	}
1202 
1203 	ret = __ieee80211_request_sched_scan_start(sdata, req);
1204 
1205 	mutex_unlock(&local->mtx);
1206 	return ret;
1207 }
1208 
1209 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1210 {
1211 	struct ieee80211_sub_if_data *sched_scan_sdata;
1212 	int ret = -ENOENT;
1213 
1214 	mutex_lock(&local->mtx);
1215 
1216 	if (!local->ops->sched_scan_stop) {
1217 		ret = -ENOTSUPP;
1218 		goto out;
1219 	}
1220 
1221 	/* We don't want to restart sched scan anymore. */
1222 	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1223 
1224 	sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1225 						lockdep_is_held(&local->mtx));
1226 	if (sched_scan_sdata) {
1227 		ret = drv_sched_scan_stop(local, sched_scan_sdata);
1228 		if (!ret)
1229 			RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1230 	}
1231 out:
1232 	mutex_unlock(&local->mtx);
1233 
1234 	return ret;
1235 }
1236 
1237 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1238 {
1239 	struct ieee80211_local *local = hw_to_local(hw);
1240 
1241 	trace_api_sched_scan_results(local);
1242 
1243 	cfg80211_sched_scan_results(hw->wiphy, 0);
1244 }
1245 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1246 
1247 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1248 {
1249 	mutex_lock(&local->mtx);
1250 
1251 	if (!rcu_access_pointer(local->sched_scan_sdata)) {
1252 		mutex_unlock(&local->mtx);
1253 		return;
1254 	}
1255 
1256 	RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1257 
1258 	/* If sched scan was aborted by the driver. */
1259 	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1260 
1261 	mutex_unlock(&local->mtx);
1262 
1263 	cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1264 }
1265 
1266 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1267 {
1268 	struct ieee80211_local *local =
1269 		container_of(work, struct ieee80211_local,
1270 			     sched_scan_stopped_work);
1271 
1272 	ieee80211_sched_scan_end(local);
1273 }
1274 
1275 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1276 {
1277 	struct ieee80211_local *local = hw_to_local(hw);
1278 
1279 	trace_api_sched_scan_stopped(local);
1280 
1281 	/*
1282 	 * this shouldn't really happen, so for simplicity
1283 	 * simply ignore it, and let mac80211 reconfigure
1284 	 * the sched scan later on.
1285 	 */
1286 	if (local->in_reconfig)
1287 		return;
1288 
1289 	schedule_work(&local->sched_scan_stopped_work);
1290 }
1291 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);
1292