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 <linux/random.h>
24 #include <net/mac80211.h>
25
26 #include "ieee80211_i.h"
27 #include "driver-ops.h"
28 #include "mesh.h"
29
30 #define IEEE80211_PROBE_DELAY (HZ / 33)
31 #define IEEE80211_CHANNEL_TIME (HZ / 33)
32 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
33
ieee80211_rx_bss_put(struct ieee80211_local * local,struct ieee80211_bss * bss)34 void ieee80211_rx_bss_put(struct ieee80211_local *local,
35 struct ieee80211_bss *bss)
36 {
37 if (!bss)
38 return;
39 cfg80211_put_bss(local->hw.wiphy,
40 container_of((void *)bss, struct cfg80211_bss, priv));
41 }
42
is_uapsd_supported(struct ieee802_11_elems * elems)43 static bool is_uapsd_supported(struct ieee802_11_elems *elems)
44 {
45 u8 qos_info;
46
47 if (elems->wmm_info && elems->wmm_info_len == 7
48 && elems->wmm_info[5] == 1)
49 qos_info = elems->wmm_info[6];
50 else if (elems->wmm_param && elems->wmm_param_len == 24
51 && elems->wmm_param[5] == 1)
52 qos_info = elems->wmm_param[6];
53 else
54 /* no valid wmm information or parameter element found */
55 return false;
56
57 return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
58 }
59
60 struct ieee80211_bss *
ieee80211_bss_info_update(struct ieee80211_local * local,struct ieee80211_rx_status * rx_status,struct ieee80211_mgmt * mgmt,size_t len,struct ieee802_11_elems * elems,struct ieee80211_channel * channel)61 ieee80211_bss_info_update(struct ieee80211_local *local,
62 struct ieee80211_rx_status *rx_status,
63 struct ieee80211_mgmt *mgmt, size_t len,
64 struct ieee802_11_elems *elems,
65 struct ieee80211_channel *channel)
66 {
67 bool beacon = ieee80211_is_beacon(mgmt->frame_control);
68 struct cfg80211_bss *cbss;
69 struct ieee80211_bss *bss;
70 int clen, srlen;
71 struct cfg80211_inform_bss bss_meta = {
72 .boottime_ns = rx_status->boottime_ns,
73 };
74 bool signal_valid;
75 struct ieee80211_sub_if_data *scan_sdata;
76
77 if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL)
78 bss_meta.signal = 0; /* invalid signal indication */
79 else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
80 bss_meta.signal = rx_status->signal * 100;
81 else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
82 bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
83
84 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20;
85 if (rx_status->bw == RATE_INFO_BW_5)
86 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5;
87 else if (rx_status->bw == RATE_INFO_BW_10)
88 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10;
89
90 bss_meta.chan = channel;
91
92 rcu_read_lock();
93 scan_sdata = rcu_dereference(local->scan_sdata);
94 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
95 scan_sdata->vif.bss_conf.assoc &&
96 ieee80211_have_rx_timestamp(rx_status)) {
97 bss_meta.parent_tsf =
98 ieee80211_calculate_rx_timestamp(local, rx_status,
99 len + FCS_LEN, 24);
100 ether_addr_copy(bss_meta.parent_bssid,
101 scan_sdata->vif.bss_conf.bssid);
102 }
103 rcu_read_unlock();
104
105 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
106 mgmt, len, GFP_ATOMIC);
107 if (!cbss)
108 return NULL;
109 /* In case the signal is invalid update the status */
110 signal_valid = abs(channel->center_freq - cbss->channel->center_freq)
111 <= local->hw.wiphy->max_adj_channel_rssi_comp;
112 if (!signal_valid)
113 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
114
115 bss = (void *)cbss->priv;
116
117 if (beacon)
118 bss->device_ts_beacon = rx_status->device_timestamp;
119 else
120 bss->device_ts_presp = rx_status->device_timestamp;
121
122 if (elems->parse_error) {
123 if (beacon)
124 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
125 else
126 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
127 } else {
128 if (beacon)
129 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
130 else
131 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
132 }
133
134 /* save the ERP value so that it is available at association time */
135 if (elems->erp_info && (!elems->parse_error ||
136 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
137 bss->erp_value = elems->erp_info[0];
138 bss->has_erp_value = true;
139 if (!elems->parse_error)
140 bss->valid_data |= IEEE80211_BSS_VALID_ERP;
141 }
142
143 /* replace old supported rates if we get new values */
144 if (!elems->parse_error ||
145 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
146 srlen = 0;
147 if (elems->supp_rates) {
148 clen = IEEE80211_MAX_SUPP_RATES;
149 if (clen > elems->supp_rates_len)
150 clen = elems->supp_rates_len;
151 memcpy(bss->supp_rates, elems->supp_rates, clen);
152 srlen += clen;
153 }
154 if (elems->ext_supp_rates) {
155 clen = IEEE80211_MAX_SUPP_RATES - srlen;
156 if (clen > elems->ext_supp_rates_len)
157 clen = elems->ext_supp_rates_len;
158 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
159 clen);
160 srlen += clen;
161 }
162 if (srlen) {
163 bss->supp_rates_len = srlen;
164 if (!elems->parse_error)
165 bss->valid_data |= IEEE80211_BSS_VALID_RATES;
166 }
167 }
168
169 if (!elems->parse_error ||
170 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
171 bss->wmm_used = elems->wmm_param || elems->wmm_info;
172 bss->uapsd_supported = is_uapsd_supported(elems);
173 if (!elems->parse_error)
174 bss->valid_data |= IEEE80211_BSS_VALID_WMM;
175 }
176
177 if (beacon) {
178 struct ieee80211_supported_band *sband =
179 local->hw.wiphy->bands[rx_status->band];
180 if (!(rx_status->encoding == RX_ENC_HT) &&
181 !(rx_status->encoding == RX_ENC_VHT))
182 bss->beacon_rate =
183 &sband->bitrates[rx_status->rate_idx];
184 }
185
186 return bss;
187 }
188
ieee80211_scan_accept_presp(struct ieee80211_sub_if_data * sdata,u32 scan_flags,const u8 * da)189 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
190 u32 scan_flags, const u8 *da)
191 {
192 if (!sdata)
193 return false;
194 /* accept broadcast for OCE */
195 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
196 is_broadcast_ether_addr(da))
197 return true;
198 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
199 return true;
200 return ether_addr_equal(da, sdata->vif.addr);
201 }
202
ieee80211_scan_rx(struct ieee80211_local * local,struct sk_buff * skb)203 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
204 {
205 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
206 struct ieee80211_sub_if_data *sdata1, *sdata2;
207 struct ieee80211_mgmt *mgmt = (void *)skb->data;
208 struct ieee80211_bss *bss;
209 u8 *elements;
210 struct ieee80211_channel *channel;
211 size_t baselen;
212 struct ieee802_11_elems elems;
213
214 if (skb->len < 24 ||
215 (!ieee80211_is_probe_resp(mgmt->frame_control) &&
216 !ieee80211_is_beacon(mgmt->frame_control)))
217 return;
218
219 sdata1 = rcu_dereference(local->scan_sdata);
220 sdata2 = rcu_dereference(local->sched_scan_sdata);
221
222 if (likely(!sdata1 && !sdata2))
223 return;
224
225 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
226 struct cfg80211_scan_request *scan_req;
227 struct cfg80211_sched_scan_request *sched_scan_req;
228 u32 scan_req_flags = 0, sched_scan_req_flags = 0;
229
230 scan_req = rcu_dereference(local->scan_req);
231 sched_scan_req = rcu_dereference(local->sched_scan_req);
232
233 if (scan_req)
234 scan_req_flags = scan_req->flags;
235
236 if (sched_scan_req)
237 sched_scan_req_flags = sched_scan_req->flags;
238
239 /* ignore ProbeResp to foreign address or non-bcast (OCE)
240 * unless scanning with randomised address
241 */
242 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
243 mgmt->da) &&
244 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
245 mgmt->da))
246 return;
247
248 elements = mgmt->u.probe_resp.variable;
249 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
250 } else {
251 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
252 elements = mgmt->u.beacon.variable;
253 }
254
255 if (baselen > skb->len)
256 return;
257
258 ieee802_11_parse_elems(elements, skb->len - baselen, false, &elems);
259
260 channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
261
262 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
263 return;
264
265 bss = ieee80211_bss_info_update(local, rx_status,
266 mgmt, skb->len, &elems,
267 channel);
268 if (bss)
269 ieee80211_rx_bss_put(local, bss);
270 }
271
272 static void
ieee80211_prepare_scan_chandef(struct cfg80211_chan_def * chandef,enum nl80211_bss_scan_width scan_width)273 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
274 enum nl80211_bss_scan_width scan_width)
275 {
276 memset(chandef, 0, sizeof(*chandef));
277 switch (scan_width) {
278 case NL80211_BSS_CHAN_WIDTH_5:
279 chandef->width = NL80211_CHAN_WIDTH_5;
280 break;
281 case NL80211_BSS_CHAN_WIDTH_10:
282 chandef->width = NL80211_CHAN_WIDTH_10;
283 break;
284 default:
285 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
286 break;
287 }
288 }
289
290 /* return false if no more work */
ieee80211_prep_hw_scan(struct ieee80211_local * local)291 static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
292 {
293 struct cfg80211_scan_request *req;
294 struct cfg80211_chan_def chandef;
295 u8 bands_used = 0;
296 int i, ielen, n_chans;
297 u32 flags = 0;
298
299 req = rcu_dereference_protected(local->scan_req,
300 lockdep_is_held(&local->mtx));
301
302 if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
303 return false;
304
305 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
306 for (i = 0; i < req->n_channels; i++) {
307 local->hw_scan_req->req.channels[i] = req->channels[i];
308 bands_used |= BIT(req->channels[i]->band);
309 }
310
311 n_chans = req->n_channels;
312 } else {
313 do {
314 if (local->hw_scan_band == NUM_NL80211_BANDS)
315 return false;
316
317 n_chans = 0;
318
319 for (i = 0; i < req->n_channels; i++) {
320 if (req->channels[i]->band !=
321 local->hw_scan_band)
322 continue;
323 local->hw_scan_req->req.channels[n_chans] =
324 req->channels[i];
325 n_chans++;
326 bands_used |= BIT(req->channels[i]->band);
327 }
328
329 local->hw_scan_band++;
330 } while (!n_chans);
331 }
332
333 local->hw_scan_req->req.n_channels = n_chans;
334 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
335
336 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
337 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
338
339 ielen = ieee80211_build_preq_ies(local,
340 (u8 *)local->hw_scan_req->req.ie,
341 local->hw_scan_ies_bufsize,
342 &local->hw_scan_req->ies,
343 req->ie, req->ie_len,
344 bands_used, req->rates, &chandef,
345 flags);
346 local->hw_scan_req->req.ie_len = ielen;
347 local->hw_scan_req->req.no_cck = req->no_cck;
348 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
349 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
350 req->mac_addr_mask);
351 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
352
353 return true;
354 }
355
__ieee80211_scan_completed(struct ieee80211_hw * hw,bool aborted)356 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
357 {
358 struct ieee80211_local *local = hw_to_local(hw);
359 bool hw_scan = local->ops->hw_scan;
360 bool was_scanning = local->scanning;
361 struct cfg80211_scan_request *scan_req;
362 struct ieee80211_sub_if_data *scan_sdata;
363 struct ieee80211_sub_if_data *sdata;
364
365 lockdep_assert_held(&local->mtx);
366
367 /*
368 * It's ok to abort a not-yet-running scan (that
369 * we have one at all will be verified by checking
370 * local->scan_req next), but not to complete it
371 * successfully.
372 */
373 if (WARN_ON(!local->scanning && !aborted))
374 aborted = true;
375
376 if (WARN_ON(!local->scan_req))
377 return;
378
379 if (hw_scan && !aborted &&
380 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
381 ieee80211_prep_hw_scan(local)) {
382 int rc;
383
384 rc = drv_hw_scan(local,
385 rcu_dereference_protected(local->scan_sdata,
386 lockdep_is_held(&local->mtx)),
387 local->hw_scan_req);
388
389 if (rc == 0)
390 return;
391
392 /* HW scan failed and is going to be reported as aborted,
393 * so clear old scan info.
394 */
395 memset(&local->scan_info, 0, sizeof(local->scan_info));
396 aborted = true;
397 }
398
399 kfree(local->hw_scan_req);
400 local->hw_scan_req = NULL;
401
402 scan_req = rcu_dereference_protected(local->scan_req,
403 lockdep_is_held(&local->mtx));
404
405 if (scan_req != local->int_scan_req) {
406 local->scan_info.aborted = aborted;
407 cfg80211_scan_done(scan_req, &local->scan_info);
408 }
409 RCU_INIT_POINTER(local->scan_req, NULL);
410
411 scan_sdata = rcu_dereference_protected(local->scan_sdata,
412 lockdep_is_held(&local->mtx));
413 RCU_INIT_POINTER(local->scan_sdata, NULL);
414
415 local->scanning = 0;
416 local->scan_chandef.chan = NULL;
417
418 /* Set power back to normal operating levels. */
419 ieee80211_hw_config(local, 0);
420
421 if (!hw_scan) {
422 ieee80211_configure_filter(local);
423 drv_sw_scan_complete(local, scan_sdata);
424 ieee80211_offchannel_return(local);
425 }
426
427 ieee80211_recalc_idle(local);
428
429 ieee80211_mlme_notify_scan_completed(local);
430 ieee80211_ibss_notify_scan_completed(local);
431
432 /* Requeue all the work that might have been ignored while
433 * the scan was in progress; if there was none this will
434 * just be a no-op for the particular interface.
435 */
436 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
437 if (ieee80211_sdata_running(sdata))
438 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
439 }
440
441 if (was_scanning)
442 ieee80211_start_next_roc(local);
443 }
444
ieee80211_scan_completed(struct ieee80211_hw * hw,struct cfg80211_scan_info * info)445 void ieee80211_scan_completed(struct ieee80211_hw *hw,
446 struct cfg80211_scan_info *info)
447 {
448 struct ieee80211_local *local = hw_to_local(hw);
449
450 trace_api_scan_completed(local, info->aborted);
451
452 set_bit(SCAN_COMPLETED, &local->scanning);
453 if (info->aborted)
454 set_bit(SCAN_ABORTED, &local->scanning);
455
456 memcpy(&local->scan_info, info, sizeof(*info));
457
458 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
459 }
460 EXPORT_SYMBOL(ieee80211_scan_completed);
461
ieee80211_start_sw_scan(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata)462 static int ieee80211_start_sw_scan(struct ieee80211_local *local,
463 struct ieee80211_sub_if_data *sdata)
464 {
465 /* Software scan is not supported in multi-channel cases */
466 if (local->use_chanctx)
467 return -EOPNOTSUPP;
468
469 /*
470 * Hardware/driver doesn't support hw_scan, so use software
471 * scanning instead. First send a nullfunc frame with power save
472 * bit on so that AP will buffer the frames for us while we are not
473 * listening, then send probe requests to each channel and wait for
474 * the responses. After all channels are scanned, tune back to the
475 * original channel and send a nullfunc frame with power save bit
476 * off to trigger the AP to send us all the buffered frames.
477 *
478 * Note that while local->sw_scanning is true everything else but
479 * nullfunc frames and probe requests will be dropped in
480 * ieee80211_tx_h_check_assoc().
481 */
482 drv_sw_scan_start(local, sdata, local->scan_addr);
483
484 local->leave_oper_channel_time = jiffies;
485 local->next_scan_state = SCAN_DECISION;
486 local->scan_channel_idx = 0;
487
488 ieee80211_offchannel_stop_vifs(local);
489
490 /* ensure nullfunc is transmitted before leaving operating channel */
491 ieee80211_flush_queues(local, NULL, false);
492
493 ieee80211_configure_filter(local);
494
495 /* We need to set power level at maximum rate for scanning. */
496 ieee80211_hw_config(local, 0);
497
498 ieee80211_queue_delayed_work(&local->hw,
499 &local->scan_work, 0);
500
501 return 0;
502 }
503
ieee80211_can_scan(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata)504 static bool ieee80211_can_scan(struct ieee80211_local *local,
505 struct ieee80211_sub_if_data *sdata)
506 {
507 if (ieee80211_is_radar_required(local))
508 return false;
509
510 if (!list_empty(&local->roc_list))
511 return false;
512
513 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
514 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
515 return false;
516
517 return true;
518 }
519
ieee80211_run_deferred_scan(struct ieee80211_local * local)520 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
521 {
522 lockdep_assert_held(&local->mtx);
523
524 if (!local->scan_req || local->scanning)
525 return;
526
527 if (!ieee80211_can_scan(local,
528 rcu_dereference_protected(
529 local->scan_sdata,
530 lockdep_is_held(&local->mtx))))
531 return;
532
533 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
534 round_jiffies_relative(0));
535 }
536
ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data * sdata,const u8 * src,const u8 * dst,const u8 * ssid,size_t ssid_len,const u8 * ie,size_t ie_len,u32 ratemask,u32 flags,u32 tx_flags,struct ieee80211_channel * channel)537 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
538 const u8 *src, const u8 *dst,
539 const u8 *ssid, size_t ssid_len,
540 const u8 *ie, size_t ie_len,
541 u32 ratemask, u32 flags, u32 tx_flags,
542 struct ieee80211_channel *channel)
543 {
544 struct sk_buff *skb;
545 u32 txdata_flags = 0;
546
547 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
548 ssid, ssid_len,
549 ie, ie_len, flags);
550
551 if (skb) {
552 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
553 struct ieee80211_hdr *hdr = (void *)skb->data;
554 u16 sn = get_random_u32();
555
556 txdata_flags |= IEEE80211_TX_NO_SEQNO;
557 hdr->seq_ctrl =
558 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
559 }
560 IEEE80211_SKB_CB(skb)->flags |= tx_flags;
561 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band,
562 txdata_flags);
563 }
564 }
565
ieee80211_scan_state_send_probe(struct ieee80211_local * local,unsigned long * next_delay)566 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
567 unsigned long *next_delay)
568 {
569 int i;
570 struct ieee80211_sub_if_data *sdata;
571 struct cfg80211_scan_request *scan_req;
572 enum nl80211_band band = local->hw.conf.chandef.chan->band;
573 u32 flags = 0, tx_flags;
574
575 scan_req = rcu_dereference_protected(local->scan_req,
576 lockdep_is_held(&local->mtx));
577
578 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
579 if (scan_req->no_cck)
580 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
581 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
582 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
583 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
584 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
585
586 sdata = rcu_dereference_protected(local->scan_sdata,
587 lockdep_is_held(&local->mtx));
588
589 for (i = 0; i < scan_req->n_ssids; i++)
590 ieee80211_send_scan_probe_req(
591 sdata, local->scan_addr, scan_req->bssid,
592 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
593 scan_req->ie, scan_req->ie_len,
594 scan_req->rates[band], flags,
595 tx_flags, local->hw.conf.chandef.chan);
596
597 /*
598 * After sending probe requests, wait for probe responses
599 * on the channel.
600 */
601 *next_delay = IEEE80211_CHANNEL_TIME;
602 local->next_scan_state = SCAN_DECISION;
603 }
604
__ieee80211_start_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)605 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
606 struct cfg80211_scan_request *req)
607 {
608 struct ieee80211_local *local = sdata->local;
609 int rc;
610
611 lockdep_assert_held(&local->mtx);
612
613 if (local->scan_req || ieee80211_is_radar_required(local))
614 return -EBUSY;
615
616 if (!ieee80211_can_scan(local, sdata)) {
617 /* wait for the work to finish/time out */
618 rcu_assign_pointer(local->scan_req, req);
619 rcu_assign_pointer(local->scan_sdata, sdata);
620 return 0;
621 }
622
623 if (local->ops->hw_scan) {
624 u8 *ies;
625
626 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
627
628 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
629 int i, n_bands = 0;
630 u8 bands_counted = 0;
631
632 for (i = 0; i < req->n_channels; i++) {
633 if (bands_counted & BIT(req->channels[i]->band))
634 continue;
635 bands_counted |= BIT(req->channels[i]->band);
636 n_bands++;
637 }
638
639 local->hw_scan_ies_bufsize *= n_bands;
640 }
641
642 local->hw_scan_req = kmalloc(
643 sizeof(*local->hw_scan_req) +
644 req->n_channels * sizeof(req->channels[0]) +
645 local->hw_scan_ies_bufsize, GFP_KERNEL);
646 if (!local->hw_scan_req)
647 return -ENOMEM;
648
649 local->hw_scan_req->req.ssids = req->ssids;
650 local->hw_scan_req->req.n_ssids = req->n_ssids;
651 ies = (u8 *)local->hw_scan_req +
652 sizeof(*local->hw_scan_req) +
653 req->n_channels * sizeof(req->channels[0]);
654 local->hw_scan_req->req.ie = ies;
655 local->hw_scan_req->req.flags = req->flags;
656 eth_broadcast_addr(local->hw_scan_req->req.bssid);
657 local->hw_scan_req->req.duration = req->duration;
658 local->hw_scan_req->req.duration_mandatory =
659 req->duration_mandatory;
660
661 local->hw_scan_band = 0;
662
663 /*
664 * After allocating local->hw_scan_req, we must
665 * go through until ieee80211_prep_hw_scan(), so
666 * anything that might be changed here and leave
667 * this function early must not go after this
668 * allocation.
669 */
670 }
671
672 rcu_assign_pointer(local->scan_req, req);
673 rcu_assign_pointer(local->scan_sdata, sdata);
674
675 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
676 get_random_mask_addr(local->scan_addr,
677 req->mac_addr,
678 req->mac_addr_mask);
679 else
680 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
681
682 if (local->ops->hw_scan) {
683 __set_bit(SCAN_HW_SCANNING, &local->scanning);
684 } else if ((req->n_channels == 1) &&
685 (req->channels[0] == local->_oper_chandef.chan)) {
686 /*
687 * If we are scanning only on the operating channel
688 * then we do not need to stop normal activities
689 */
690 unsigned long next_delay;
691
692 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
693
694 ieee80211_recalc_idle(local);
695
696 /* Notify driver scan is starting, keep order of operations
697 * same as normal software scan, in case that matters. */
698 drv_sw_scan_start(local, sdata, local->scan_addr);
699
700 ieee80211_configure_filter(local); /* accept probe-responses */
701
702 /* We need to ensure power level is at max for scanning. */
703 ieee80211_hw_config(local, 0);
704
705 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
706 IEEE80211_CHAN_RADAR)) ||
707 !req->n_ssids) {
708 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
709 } else {
710 ieee80211_scan_state_send_probe(local, &next_delay);
711 next_delay = IEEE80211_CHANNEL_TIME;
712 }
713
714 /* Now, just wait a bit and we are all done! */
715 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
716 next_delay);
717 return 0;
718 } else {
719 /* Do normal software scan */
720 __set_bit(SCAN_SW_SCANNING, &local->scanning);
721 }
722
723 ieee80211_recalc_idle(local);
724
725 if (local->ops->hw_scan) {
726 WARN_ON(!ieee80211_prep_hw_scan(local));
727 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
728 } else {
729 rc = ieee80211_start_sw_scan(local, sdata);
730 }
731
732 if (rc) {
733 kfree(local->hw_scan_req);
734 local->hw_scan_req = NULL;
735 local->scanning = 0;
736
737 ieee80211_recalc_idle(local);
738
739 local->scan_req = NULL;
740 RCU_INIT_POINTER(local->scan_sdata, NULL);
741 }
742
743 return rc;
744 }
745
746 static unsigned long
ieee80211_scan_get_channel_time(struct ieee80211_channel * chan)747 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
748 {
749 /*
750 * TODO: channel switching also consumes quite some time,
751 * add that delay as well to get a better estimation
752 */
753 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
754 return IEEE80211_PASSIVE_CHANNEL_TIME;
755 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
756 }
757
ieee80211_scan_state_decision(struct ieee80211_local * local,unsigned long * next_delay)758 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
759 unsigned long *next_delay)
760 {
761 bool associated = false;
762 bool tx_empty = true;
763 bool bad_latency;
764 struct ieee80211_sub_if_data *sdata;
765 struct ieee80211_channel *next_chan;
766 enum mac80211_scan_state next_scan_state;
767 struct cfg80211_scan_request *scan_req;
768
769 /*
770 * check if at least one STA interface is associated,
771 * check if at least one STA interface has pending tx frames
772 * and grab the lowest used beacon interval
773 */
774 mutex_lock(&local->iflist_mtx);
775 list_for_each_entry(sdata, &local->interfaces, list) {
776 if (!ieee80211_sdata_running(sdata))
777 continue;
778
779 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
780 if (sdata->u.mgd.associated) {
781 associated = true;
782
783 if (!qdisc_all_tx_empty(sdata->dev)) {
784 tx_empty = false;
785 break;
786 }
787 }
788 }
789 }
790 mutex_unlock(&local->iflist_mtx);
791
792 scan_req = rcu_dereference_protected(local->scan_req,
793 lockdep_is_held(&local->mtx));
794
795 next_chan = scan_req->channels[local->scan_channel_idx];
796
797 /*
798 * we're currently scanning a different channel, let's
799 * see if we can scan another channel without interfering
800 * with the current traffic situation.
801 *
802 * Keep good latency, do not stay off-channel more than 125 ms.
803 */
804
805 bad_latency = time_after(jiffies +
806 ieee80211_scan_get_channel_time(next_chan),
807 local->leave_oper_channel_time + HZ / 8);
808
809 if (associated && !tx_empty) {
810 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
811 next_scan_state = SCAN_ABORT;
812 else
813 next_scan_state = SCAN_SUSPEND;
814 } else if (associated && bad_latency) {
815 next_scan_state = SCAN_SUSPEND;
816 } else {
817 next_scan_state = SCAN_SET_CHANNEL;
818 }
819
820 local->next_scan_state = next_scan_state;
821
822 *next_delay = 0;
823 }
824
ieee80211_scan_state_set_channel(struct ieee80211_local * local,unsigned long * next_delay)825 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
826 unsigned long *next_delay)
827 {
828 int skip;
829 struct ieee80211_channel *chan;
830 enum nl80211_bss_scan_width oper_scan_width;
831 struct cfg80211_scan_request *scan_req;
832
833 scan_req = rcu_dereference_protected(local->scan_req,
834 lockdep_is_held(&local->mtx));
835
836 skip = 0;
837 chan = scan_req->channels[local->scan_channel_idx];
838
839 local->scan_chandef.chan = chan;
840 local->scan_chandef.center_freq1 = chan->center_freq;
841 local->scan_chandef.center_freq2 = 0;
842 switch (scan_req->scan_width) {
843 case NL80211_BSS_CHAN_WIDTH_5:
844 local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
845 break;
846 case NL80211_BSS_CHAN_WIDTH_10:
847 local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
848 break;
849 case NL80211_BSS_CHAN_WIDTH_20:
850 /* If scanning on oper channel, use whatever channel-type
851 * is currently in use.
852 */
853 oper_scan_width = cfg80211_chandef_to_scan_width(
854 &local->_oper_chandef);
855 if (chan == local->_oper_chandef.chan &&
856 oper_scan_width == scan_req->scan_width)
857 local->scan_chandef = local->_oper_chandef;
858 else
859 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
860 break;
861 }
862
863 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
864 skip = 1;
865
866 /* advance state machine to next channel/band */
867 local->scan_channel_idx++;
868
869 if (skip) {
870 /* if we skip this channel return to the decision state */
871 local->next_scan_state = SCAN_DECISION;
872 return;
873 }
874
875 /*
876 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
877 * (which unfortunately doesn't say _why_ step a) is done,
878 * but it waits for the probe delay or until a frame is
879 * received - and the received frame would update the NAV).
880 * For now, we do not support waiting until a frame is
881 * received.
882 *
883 * In any case, it is not necessary for a passive scan.
884 */
885 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
886 !scan_req->n_ssids) {
887 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
888 local->next_scan_state = SCAN_DECISION;
889 return;
890 }
891
892 /* active scan, send probes */
893 *next_delay = IEEE80211_PROBE_DELAY;
894 local->next_scan_state = SCAN_SEND_PROBE;
895 }
896
ieee80211_scan_state_suspend(struct ieee80211_local * local,unsigned long * next_delay)897 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
898 unsigned long *next_delay)
899 {
900 /* switch back to the operating channel */
901 local->scan_chandef.chan = NULL;
902 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
903
904 /* disable PS */
905 ieee80211_offchannel_return(local);
906
907 *next_delay = HZ / 5;
908 /* afterwards, resume scan & go to next channel */
909 local->next_scan_state = SCAN_RESUME;
910 }
911
ieee80211_scan_state_resume(struct ieee80211_local * local,unsigned long * next_delay)912 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
913 unsigned long *next_delay)
914 {
915 ieee80211_offchannel_stop_vifs(local);
916
917 if (local->ops->flush) {
918 ieee80211_flush_queues(local, NULL, false);
919 *next_delay = 0;
920 } else
921 *next_delay = HZ / 10;
922
923 /* remember when we left the operating channel */
924 local->leave_oper_channel_time = jiffies;
925
926 /* advance to the next channel to be scanned */
927 local->next_scan_state = SCAN_SET_CHANNEL;
928 }
929
ieee80211_scan_work(struct work_struct * work)930 void ieee80211_scan_work(struct work_struct *work)
931 {
932 struct ieee80211_local *local =
933 container_of(work, struct ieee80211_local, scan_work.work);
934 struct ieee80211_sub_if_data *sdata;
935 struct cfg80211_scan_request *scan_req;
936 unsigned long next_delay = 0;
937 bool aborted;
938
939 mutex_lock(&local->mtx);
940
941 if (!ieee80211_can_run_worker(local)) {
942 aborted = true;
943 goto out_complete;
944 }
945
946 sdata = rcu_dereference_protected(local->scan_sdata,
947 lockdep_is_held(&local->mtx));
948 scan_req = rcu_dereference_protected(local->scan_req,
949 lockdep_is_held(&local->mtx));
950
951 /* When scanning on-channel, the first-callback means completed. */
952 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
953 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
954 goto out_complete;
955 }
956
957 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
958 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
959 goto out_complete;
960 }
961
962 if (!sdata || !scan_req)
963 goto out;
964
965 if (!local->scanning) {
966 int rc;
967
968 RCU_INIT_POINTER(local->scan_req, NULL);
969 RCU_INIT_POINTER(local->scan_sdata, NULL);
970
971 rc = __ieee80211_start_scan(sdata, scan_req);
972 if (rc) {
973 /* need to complete scan in cfg80211 */
974 rcu_assign_pointer(local->scan_req, scan_req);
975 aborted = true;
976 goto out_complete;
977 } else
978 goto out;
979 }
980
981 /*
982 * as long as no delay is required advance immediately
983 * without scheduling a new work
984 */
985 do {
986 if (!ieee80211_sdata_running(sdata)) {
987 aborted = true;
988 goto out_complete;
989 }
990
991 switch (local->next_scan_state) {
992 case SCAN_DECISION:
993 /* if no more bands/channels left, complete scan */
994 if (local->scan_channel_idx >= scan_req->n_channels) {
995 aborted = false;
996 goto out_complete;
997 }
998 ieee80211_scan_state_decision(local, &next_delay);
999 break;
1000 case SCAN_SET_CHANNEL:
1001 ieee80211_scan_state_set_channel(local, &next_delay);
1002 break;
1003 case SCAN_SEND_PROBE:
1004 ieee80211_scan_state_send_probe(local, &next_delay);
1005 break;
1006 case SCAN_SUSPEND:
1007 ieee80211_scan_state_suspend(local, &next_delay);
1008 break;
1009 case SCAN_RESUME:
1010 ieee80211_scan_state_resume(local, &next_delay);
1011 break;
1012 case SCAN_ABORT:
1013 aborted = true;
1014 goto out_complete;
1015 }
1016 } while (next_delay == 0);
1017
1018 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
1019 goto out;
1020
1021 out_complete:
1022 __ieee80211_scan_completed(&local->hw, aborted);
1023 out:
1024 mutex_unlock(&local->mtx);
1025 }
1026
ieee80211_request_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)1027 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1028 struct cfg80211_scan_request *req)
1029 {
1030 int res;
1031
1032 mutex_lock(&sdata->local->mtx);
1033 res = __ieee80211_start_scan(sdata, req);
1034 mutex_unlock(&sdata->local->mtx);
1035
1036 return res;
1037 }
1038
ieee80211_request_ibss_scan(struct ieee80211_sub_if_data * sdata,const u8 * ssid,u8 ssid_len,struct ieee80211_channel ** channels,unsigned int n_channels,enum nl80211_bss_scan_width scan_width)1039 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1040 const u8 *ssid, u8 ssid_len,
1041 struct ieee80211_channel **channels,
1042 unsigned int n_channels,
1043 enum nl80211_bss_scan_width scan_width)
1044 {
1045 struct ieee80211_local *local = sdata->local;
1046 int ret = -EBUSY, i, n_ch = 0;
1047 enum nl80211_band band;
1048
1049 mutex_lock(&local->mtx);
1050
1051 /* busy scanning */
1052 if (local->scan_req)
1053 goto unlock;
1054
1055 /* fill internal scan request */
1056 if (!channels) {
1057 int max_n;
1058
1059 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1060 if (!local->hw.wiphy->bands[band])
1061 continue;
1062
1063 max_n = local->hw.wiphy->bands[band]->n_channels;
1064 for (i = 0; i < max_n; i++) {
1065 struct ieee80211_channel *tmp_ch =
1066 &local->hw.wiphy->bands[band]->channels[i];
1067
1068 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1069 IEEE80211_CHAN_DISABLED))
1070 continue;
1071
1072 local->int_scan_req->channels[n_ch] = tmp_ch;
1073 n_ch++;
1074 }
1075 }
1076
1077 if (WARN_ON_ONCE(n_ch == 0))
1078 goto unlock;
1079
1080 local->int_scan_req->n_channels = n_ch;
1081 } else {
1082 for (i = 0; i < n_channels; i++) {
1083 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1084 IEEE80211_CHAN_DISABLED))
1085 continue;
1086
1087 local->int_scan_req->channels[n_ch] = channels[i];
1088 n_ch++;
1089 }
1090
1091 if (WARN_ON_ONCE(n_ch == 0))
1092 goto unlock;
1093
1094 local->int_scan_req->n_channels = n_ch;
1095 }
1096
1097 local->int_scan_req->ssids = &local->scan_ssid;
1098 local->int_scan_req->n_ssids = 1;
1099 local->int_scan_req->scan_width = scan_width;
1100 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1101 local->int_scan_req->ssids[0].ssid_len = ssid_len;
1102
1103 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1104 unlock:
1105 mutex_unlock(&local->mtx);
1106 return ret;
1107 }
1108
1109 /*
1110 * Only call this function when a scan can't be queued -- under RTNL.
1111 */
ieee80211_scan_cancel(struct ieee80211_local * local)1112 void ieee80211_scan_cancel(struct ieee80211_local *local)
1113 {
1114 /*
1115 * We are canceling software scan, or deferred scan that was not
1116 * yet really started (see __ieee80211_start_scan ).
1117 *
1118 * Regarding hardware scan:
1119 * - we can not call __ieee80211_scan_completed() as when
1120 * SCAN_HW_SCANNING bit is set this function change
1121 * local->hw_scan_req to operate on 5G band, what race with
1122 * driver which can use local->hw_scan_req
1123 *
1124 * - we can not cancel scan_work since driver can schedule it
1125 * by ieee80211_scan_completed(..., true) to finish scan
1126 *
1127 * Hence we only call the cancel_hw_scan() callback, but the low-level
1128 * driver is still responsible for calling ieee80211_scan_completed()
1129 * after the scan was completed/aborted.
1130 */
1131
1132 mutex_lock(&local->mtx);
1133 if (!local->scan_req)
1134 goto out;
1135
1136 /*
1137 * We have a scan running and the driver already reported completion,
1138 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1139 * cancelled.
1140 */
1141 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1142 test_bit(SCAN_COMPLETED, &local->scanning)) {
1143 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1144 goto out;
1145 }
1146
1147 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1148 /*
1149 * Make sure that __ieee80211_scan_completed doesn't trigger a
1150 * scan on another band.
1151 */
1152 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1153 if (local->ops->cancel_hw_scan)
1154 drv_cancel_hw_scan(local,
1155 rcu_dereference_protected(local->scan_sdata,
1156 lockdep_is_held(&local->mtx)));
1157 goto out;
1158 }
1159
1160 /*
1161 * If the work is currently running, it must be blocked on
1162 * the mutex, but we'll set scan_sdata = NULL and it'll
1163 * simply exit once it acquires the mutex.
1164 */
1165 cancel_delayed_work(&local->scan_work);
1166 /* and clean up */
1167 memset(&local->scan_info, 0, sizeof(local->scan_info));
1168 __ieee80211_scan_completed(&local->hw, true);
1169 out:
1170 mutex_unlock(&local->mtx);
1171 }
1172
__ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1173 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1174 struct cfg80211_sched_scan_request *req)
1175 {
1176 struct ieee80211_local *local = sdata->local;
1177 struct ieee80211_scan_ies sched_scan_ies = {};
1178 struct cfg80211_chan_def chandef;
1179 int ret, i, iebufsz, num_bands = 0;
1180 u32 rate_masks[NUM_NL80211_BANDS] = {};
1181 u8 bands_used = 0;
1182 u8 *ie;
1183 u32 flags = 0;
1184
1185 iebufsz = local->scan_ies_len + req->ie_len;
1186
1187 lockdep_assert_held(&local->mtx);
1188
1189 if (!local->ops->sched_scan_start)
1190 return -ENOTSUPP;
1191
1192 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1193 if (local->hw.wiphy->bands[i]) {
1194 bands_used |= BIT(i);
1195 rate_masks[i] = (u32) -1;
1196 num_bands++;
1197 }
1198 }
1199
1200 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1201 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1202
1203 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1204 if (!ie) {
1205 ret = -ENOMEM;
1206 goto out;
1207 }
1208
1209 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1210
1211 ieee80211_build_preq_ies(local, ie, num_bands * iebufsz,
1212 &sched_scan_ies, req->ie,
1213 req->ie_len, bands_used, rate_masks, &chandef,
1214 flags);
1215
1216 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1217 if (ret == 0) {
1218 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1219 rcu_assign_pointer(local->sched_scan_req, req);
1220 }
1221
1222 kfree(ie);
1223
1224 out:
1225 if (ret) {
1226 /* Clean in case of failure after HW restart or upon resume. */
1227 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1228 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1229 }
1230
1231 return ret;
1232 }
1233
ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1234 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1235 struct cfg80211_sched_scan_request *req)
1236 {
1237 struct ieee80211_local *local = sdata->local;
1238 int ret;
1239
1240 mutex_lock(&local->mtx);
1241
1242 if (rcu_access_pointer(local->sched_scan_sdata)) {
1243 mutex_unlock(&local->mtx);
1244 return -EBUSY;
1245 }
1246
1247 ret = __ieee80211_request_sched_scan_start(sdata, req);
1248
1249 mutex_unlock(&local->mtx);
1250 return ret;
1251 }
1252
ieee80211_request_sched_scan_stop(struct ieee80211_local * local)1253 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1254 {
1255 struct ieee80211_sub_if_data *sched_scan_sdata;
1256 int ret = -ENOENT;
1257
1258 mutex_lock(&local->mtx);
1259
1260 if (!local->ops->sched_scan_stop) {
1261 ret = -ENOTSUPP;
1262 goto out;
1263 }
1264
1265 /* We don't want to restart sched scan anymore. */
1266 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1267
1268 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1269 lockdep_is_held(&local->mtx));
1270 if (sched_scan_sdata) {
1271 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1272 if (!ret)
1273 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1274 }
1275 out:
1276 mutex_unlock(&local->mtx);
1277
1278 return ret;
1279 }
1280
ieee80211_sched_scan_results(struct ieee80211_hw * hw)1281 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1282 {
1283 struct ieee80211_local *local = hw_to_local(hw);
1284
1285 trace_api_sched_scan_results(local);
1286
1287 cfg80211_sched_scan_results(hw->wiphy, 0);
1288 }
1289 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1290
ieee80211_sched_scan_end(struct ieee80211_local * local)1291 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1292 {
1293 mutex_lock(&local->mtx);
1294
1295 if (!rcu_access_pointer(local->sched_scan_sdata)) {
1296 mutex_unlock(&local->mtx);
1297 return;
1298 }
1299
1300 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1301
1302 /* If sched scan was aborted by the driver. */
1303 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1304
1305 mutex_unlock(&local->mtx);
1306
1307 cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1308 }
1309
ieee80211_sched_scan_stopped_work(struct work_struct * work)1310 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1311 {
1312 struct ieee80211_local *local =
1313 container_of(work, struct ieee80211_local,
1314 sched_scan_stopped_work);
1315
1316 ieee80211_sched_scan_end(local);
1317 }
1318
ieee80211_sched_scan_stopped(struct ieee80211_hw * hw)1319 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1320 {
1321 struct ieee80211_local *local = hw_to_local(hw);
1322
1323 trace_api_sched_scan_stopped(local);
1324
1325 /*
1326 * this shouldn't really happen, so for simplicity
1327 * simply ignore it, and let mac80211 reconfigure
1328 * the sched scan later on.
1329 */
1330 if (local->in_reconfig)
1331 return;
1332
1333 schedule_work(&local->sched_scan_stopped_work);
1334 }
1335 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);
1336
