2 * Scanning implementation
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>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
15 #include <linux/if_arp.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/pm_qos.h>
19 #include <net/sch_generic.h>
20 #include <linux/slab.h>
21 #include <linux/export.h>
22 #include <net/mac80211.h>
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
28 #define IEEE80211_PROBE_DELAY (HZ / 33)
29 #define IEEE80211_CHANNEL_TIME (HZ / 33)
30 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
32 void ieee80211_rx_bss_put(struct ieee80211_local *local,
33 struct ieee80211_bss *bss)
37 cfg80211_put_bss(local->hw.wiphy,
38 container_of((void *)bss, struct cfg80211_bss, priv));
41 static bool is_uapsd_supported(struct ieee802_11_elems *elems)
45 if (elems->wmm_info && elems->wmm_info_len == 7
46 && elems->wmm_info[5] == 1)
47 qos_info = elems->wmm_info[6];
48 else if (elems->wmm_param && elems->wmm_param_len == 24
49 && elems->wmm_param[5] == 1)
50 qos_info = elems->wmm_param[6];
52 /* no valid wmm information or parameter element found */
55 return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
58 struct ieee80211_bss *
59 ieee80211_bss_info_update(struct ieee80211_local *local,
60 struct ieee80211_rx_status *rx_status,
61 struct ieee80211_mgmt *mgmt, size_t len,
62 struct ieee802_11_elems *elems,
63 struct ieee80211_channel *channel)
65 bool beacon = ieee80211_is_beacon(mgmt->frame_control);
66 struct cfg80211_bss *cbss;
67 struct ieee80211_bss *bss;
71 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
72 signal = rx_status->signal * 100;
73 else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
74 signal = (rx_status->signal * 100) / local->hw.max_signal;
76 cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel,
77 mgmt, len, signal, GFP_ATOMIC);
81 bss = (void *)cbss->priv;
84 bss->device_ts_beacon = rx_status->device_timestamp;
86 bss->device_ts_presp = rx_status->device_timestamp;
88 if (elems->parse_error) {
90 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
92 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
95 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
97 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
100 /* save the ERP value so that it is available at association time */
101 if (elems->erp_info && elems->erp_info_len >= 1 &&
102 (!elems->parse_error ||
103 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
104 bss->erp_value = elems->erp_info[0];
105 bss->has_erp_value = true;
106 if (!elems->parse_error)
107 bss->valid_data |= IEEE80211_BSS_VALID_ERP;
110 /* replace old supported rates if we get new values */
111 if (!elems->parse_error ||
112 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
114 if (elems->supp_rates) {
115 clen = IEEE80211_MAX_SUPP_RATES;
116 if (clen > elems->supp_rates_len)
117 clen = elems->supp_rates_len;
118 memcpy(bss->supp_rates, elems->supp_rates, clen);
121 if (elems->ext_supp_rates) {
122 clen = IEEE80211_MAX_SUPP_RATES - srlen;
123 if (clen > elems->ext_supp_rates_len)
124 clen = elems->ext_supp_rates_len;
125 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
130 bss->supp_rates_len = srlen;
131 if (!elems->parse_error)
132 bss->valid_data |= IEEE80211_BSS_VALID_RATES;
136 if (!elems->parse_error ||
137 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
138 bss->wmm_used = elems->wmm_param || elems->wmm_info;
139 bss->uapsd_supported = is_uapsd_supported(elems);
140 if (!elems->parse_error)
141 bss->valid_data |= IEEE80211_BSS_VALID_WMM;
147 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
149 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
150 struct ieee80211_sub_if_data *sdata1, *sdata2;
151 struct ieee80211_mgmt *mgmt = (void *)skb->data;
152 struct ieee80211_bss *bss;
154 struct ieee80211_channel *channel;
156 struct ieee802_11_elems elems;
159 (!ieee80211_is_probe_resp(mgmt->frame_control) &&
160 !ieee80211_is_beacon(mgmt->frame_control)))
163 sdata1 = rcu_dereference(local->scan_sdata);
164 sdata2 = rcu_dereference(local->sched_scan_sdata);
166 if (likely(!sdata1 && !sdata2))
169 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
170 /* ignore ProbeResp to foreign address */
171 if ((!sdata1 || !ether_addr_equal(mgmt->da, sdata1->vif.addr)) &&
172 (!sdata2 || !ether_addr_equal(mgmt->da, sdata2->vif.addr)))
175 elements = mgmt->u.probe_resp.variable;
176 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
178 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
179 elements = mgmt->u.beacon.variable;
182 if (baselen > skb->len)
185 ieee802_11_parse_elems(elements, skb->len - baselen, &elems);
187 channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
189 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
192 bss = ieee80211_bss_info_update(local, rx_status,
193 mgmt, skb->len, &elems,
196 ieee80211_rx_bss_put(local, bss);
199 /* return false if no more work */
200 static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
202 struct cfg80211_scan_request *req = local->scan_req;
203 enum ieee80211_band band;
204 int i, ielen, n_chans;
207 if (local->hw_scan_band == IEEE80211_NUM_BANDS)
210 band = local->hw_scan_band;
212 for (i = 0; i < req->n_channels; i++) {
213 if (req->channels[i]->band == band) {
214 local->hw_scan_req->channels[n_chans] =
220 local->hw_scan_band++;
223 local->hw_scan_req->n_channels = n_chans;
225 ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie,
226 local->hw_scan_ies_bufsize,
227 req->ie, req->ie_len, band,
228 req->rates[band], 0);
229 local->hw_scan_req->ie_len = ielen;
230 local->hw_scan_req->no_cck = req->no_cck;
235 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted,
238 struct ieee80211_local *local = hw_to_local(hw);
240 lockdep_assert_held(&local->mtx);
243 * It's ok to abort a not-yet-running scan (that
244 * we have one at all will be verified by checking
245 * local->scan_req next), but not to complete it
248 if (WARN_ON(!local->scanning && !aborted))
251 if (WARN_ON(!local->scan_req))
254 if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) {
257 rc = drv_hw_scan(local,
258 rcu_dereference_protected(local->scan_sdata,
259 lockdep_is_held(&local->mtx)),
266 kfree(local->hw_scan_req);
267 local->hw_scan_req = NULL;
269 if (local->scan_req != local->int_scan_req)
270 cfg80211_scan_done(local->scan_req, aborted);
271 local->scan_req = NULL;
272 rcu_assign_pointer(local->scan_sdata, NULL);
275 local->scan_channel = NULL;
277 /* Set power back to normal operating levels. */
278 ieee80211_hw_config(local, 0);
281 ieee80211_configure_filter(local);
282 drv_sw_scan_complete(local);
283 ieee80211_offchannel_return(local);
286 ieee80211_recalc_idle(local);
288 ieee80211_mlme_notify_scan_completed(local);
289 ieee80211_ibss_notify_scan_completed(local);
290 ieee80211_mesh_notify_scan_completed(local);
291 ieee80211_start_next_roc(local);
294 void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
296 struct ieee80211_local *local = hw_to_local(hw);
298 trace_api_scan_completed(local, aborted);
300 set_bit(SCAN_COMPLETED, &local->scanning);
302 set_bit(SCAN_ABORTED, &local->scanning);
303 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
305 EXPORT_SYMBOL(ieee80211_scan_completed);
307 static int ieee80211_start_sw_scan(struct ieee80211_local *local)
309 /* Software scan is not supported in multi-channel cases */
310 if (local->use_chanctx)
314 * Hardware/driver doesn't support hw_scan, so use software
315 * scanning instead. First send a nullfunc frame with power save
316 * bit on so that AP will buffer the frames for us while we are not
317 * listening, then send probe requests to each channel and wait for
318 * the responses. After all channels are scanned, tune back to the
319 * original channel and send a nullfunc frame with power save bit
320 * off to trigger the AP to send us all the buffered frames.
322 * Note that while local->sw_scanning is true everything else but
323 * nullfunc frames and probe requests will be dropped in
324 * ieee80211_tx_h_check_assoc().
326 drv_sw_scan_start(local);
328 local->leave_oper_channel_time = jiffies;
329 local->next_scan_state = SCAN_DECISION;
330 local->scan_channel_idx = 0;
332 ieee80211_offchannel_stop_vifs(local);
334 /* ensure nullfunc is transmitted before leaving operating channel */
335 ieee80211_flush_queues(local, NULL);
337 ieee80211_configure_filter(local);
339 /* We need to set power level at maximum rate for scanning. */
340 ieee80211_hw_config(local, 0);
342 ieee80211_queue_delayed_work(&local->hw,
343 &local->scan_work, 0);
348 static bool ieee80211_can_scan(struct ieee80211_local *local,
349 struct ieee80211_sub_if_data *sdata)
351 if (local->radar_detect_enabled)
354 if (!list_empty(&local->roc_list))
357 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
358 sdata->u.mgd.flags & (IEEE80211_STA_BEACON_POLL |
359 IEEE80211_STA_CONNECTION_POLL))
365 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
367 lockdep_assert_held(&local->mtx);
369 if (!local->scan_req || local->scanning)
372 if (!ieee80211_can_scan(local,
373 rcu_dereference_protected(
375 lockdep_is_held(&local->mtx))))
378 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
379 round_jiffies_relative(0));
382 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
383 unsigned long *next_delay)
386 struct ieee80211_sub_if_data *sdata;
387 enum ieee80211_band band = local->hw.conf.channel->band;
390 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
391 if (local->scan_req->no_cck)
392 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
394 sdata = rcu_dereference_protected(local->scan_sdata,
395 lockdep_is_held(&local->mtx));
397 for (i = 0; i < local->scan_req->n_ssids; i++)
398 ieee80211_send_probe_req(
400 local->scan_req->ssids[i].ssid,
401 local->scan_req->ssids[i].ssid_len,
402 local->scan_req->ie, local->scan_req->ie_len,
403 local->scan_req->rates[band], false,
404 tx_flags, local->hw.conf.channel, true);
407 * After sending probe requests, wait for probe responses
410 *next_delay = IEEE80211_CHANNEL_TIME;
411 local->next_scan_state = SCAN_DECISION;
414 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
415 struct cfg80211_scan_request *req)
417 struct ieee80211_local *local = sdata->local;
420 lockdep_assert_held(&local->mtx);
425 if (!ieee80211_can_scan(local, sdata)) {
426 /* wait for the work to finish/time out */
427 local->scan_req = req;
428 rcu_assign_pointer(local->scan_sdata, sdata);
432 if (local->ops->hw_scan) {
435 local->hw_scan_ies_bufsize = 2 + IEEE80211_MAX_SSID_LEN +
436 local->scan_ies_len +
438 local->hw_scan_req = kmalloc(
439 sizeof(*local->hw_scan_req) +
440 req->n_channels * sizeof(req->channels[0]) +
441 local->hw_scan_ies_bufsize, GFP_KERNEL);
442 if (!local->hw_scan_req)
445 local->hw_scan_req->ssids = req->ssids;
446 local->hw_scan_req->n_ssids = req->n_ssids;
447 ies = (u8 *)local->hw_scan_req +
448 sizeof(*local->hw_scan_req) +
449 req->n_channels * sizeof(req->channels[0]);
450 local->hw_scan_req->ie = ies;
451 local->hw_scan_req->flags = req->flags;
453 local->hw_scan_band = 0;
456 * After allocating local->hw_scan_req, we must
457 * go through until ieee80211_prep_hw_scan(), so
458 * anything that might be changed here and leave
459 * this function early must not go after this
464 local->scan_req = req;
465 rcu_assign_pointer(local->scan_sdata, sdata);
467 if (local->ops->hw_scan) {
468 __set_bit(SCAN_HW_SCANNING, &local->scanning);
469 } else if ((req->n_channels == 1) &&
470 (req->channels[0] == local->_oper_channel)) {
472 * If we are scanning only on the operating channel
473 * then we do not need to stop normal activities
475 unsigned long next_delay;
477 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
479 ieee80211_recalc_idle(local);
481 /* Notify driver scan is starting, keep order of operations
482 * same as normal software scan, in case that matters. */
483 drv_sw_scan_start(local);
485 ieee80211_configure_filter(local); /* accept probe-responses */
487 /* We need to ensure power level is at max for scanning. */
488 ieee80211_hw_config(local, 0);
490 if ((req->channels[0]->flags &
491 IEEE80211_CHAN_PASSIVE_SCAN) ||
492 !local->scan_req->n_ssids) {
493 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
495 ieee80211_scan_state_send_probe(local, &next_delay);
496 next_delay = IEEE80211_CHANNEL_TIME;
499 /* Now, just wait a bit and we are all done! */
500 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
504 /* Do normal software scan */
505 __set_bit(SCAN_SW_SCANNING, &local->scanning);
508 ieee80211_recalc_idle(local);
510 if (local->ops->hw_scan) {
511 WARN_ON(!ieee80211_prep_hw_scan(local));
512 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
514 rc = ieee80211_start_sw_scan(local);
517 kfree(local->hw_scan_req);
518 local->hw_scan_req = NULL;
521 ieee80211_recalc_idle(local);
523 local->scan_req = NULL;
524 rcu_assign_pointer(local->scan_sdata, NULL);
531 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
534 * TODO: channel switching also consumes quite some time,
535 * add that delay as well to get a better estimation
537 if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN)
538 return IEEE80211_PASSIVE_CHANNEL_TIME;
539 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
542 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
543 unsigned long *next_delay)
545 bool associated = false;
546 bool tx_empty = true;
548 struct ieee80211_sub_if_data *sdata;
549 struct ieee80211_channel *next_chan;
550 enum mac80211_scan_state next_scan_state;
553 * check if at least one STA interface is associated,
554 * check if at least one STA interface has pending tx frames
555 * and grab the lowest used beacon interval
557 mutex_lock(&local->iflist_mtx);
558 list_for_each_entry(sdata, &local->interfaces, list) {
559 if (!ieee80211_sdata_running(sdata))
562 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
563 if (sdata->u.mgd.associated) {
566 if (!qdisc_all_tx_empty(sdata->dev)) {
573 mutex_unlock(&local->iflist_mtx);
575 next_chan = local->scan_req->channels[local->scan_channel_idx];
578 * we're currently scanning a different channel, let's
579 * see if we can scan another channel without interfering
580 * with the current traffic situation.
582 * Keep good latency, do not stay off-channel more than 125 ms.
585 bad_latency = time_after(jiffies +
586 ieee80211_scan_get_channel_time(next_chan),
587 local->leave_oper_channel_time + HZ / 8);
589 if (associated && !tx_empty) {
590 if (local->scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
591 next_scan_state = SCAN_ABORT;
593 next_scan_state = SCAN_SUSPEND;
594 } else if (associated && bad_latency) {
595 next_scan_state = SCAN_SUSPEND;
597 next_scan_state = SCAN_SET_CHANNEL;
600 local->next_scan_state = next_scan_state;
605 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
606 unsigned long *next_delay)
609 struct ieee80211_channel *chan;
612 chan = local->scan_req->channels[local->scan_channel_idx];
614 local->scan_channel = chan;
616 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
619 /* advance state machine to next channel/band */
620 local->scan_channel_idx++;
623 /* if we skip this channel return to the decision state */
624 local->next_scan_state = SCAN_DECISION;
629 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
630 * (which unfortunately doesn't say _why_ step a) is done,
631 * but it waits for the probe delay or until a frame is
632 * received - and the received frame would update the NAV).
633 * For now, we do not support waiting until a frame is
636 * In any case, it is not necessary for a passive scan.
638 if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
639 !local->scan_req->n_ssids) {
640 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
641 local->next_scan_state = SCAN_DECISION;
645 /* active scan, send probes */
646 *next_delay = IEEE80211_PROBE_DELAY;
647 local->next_scan_state = SCAN_SEND_PROBE;
650 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
651 unsigned long *next_delay)
653 /* switch back to the operating channel */
654 local->scan_channel = NULL;
655 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
658 ieee80211_offchannel_return(local);
660 *next_delay = HZ / 5;
661 /* afterwards, resume scan & go to next channel */
662 local->next_scan_state = SCAN_RESUME;
665 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
666 unsigned long *next_delay)
668 ieee80211_offchannel_stop_vifs(local);
670 if (local->ops->flush) {
671 ieee80211_flush_queues(local, NULL);
674 *next_delay = HZ / 10;
676 /* remember when we left the operating channel */
677 local->leave_oper_channel_time = jiffies;
679 /* advance to the next channel to be scanned */
680 local->next_scan_state = SCAN_SET_CHANNEL;
683 void ieee80211_scan_work(struct work_struct *work)
685 struct ieee80211_local *local =
686 container_of(work, struct ieee80211_local, scan_work.work);
687 struct ieee80211_sub_if_data *sdata;
688 unsigned long next_delay = 0;
689 bool aborted, hw_scan;
691 mutex_lock(&local->mtx);
693 sdata = rcu_dereference_protected(local->scan_sdata,
694 lockdep_is_held(&local->mtx));
696 /* When scanning on-channel, the first-callback means completed. */
697 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
698 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
702 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
703 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
707 if (!sdata || !local->scan_req)
710 if (local->scan_req && !local->scanning) {
711 struct cfg80211_scan_request *req = local->scan_req;
714 local->scan_req = NULL;
715 rcu_assign_pointer(local->scan_sdata, NULL);
717 rc = __ieee80211_start_scan(sdata, req);
719 /* need to complete scan in cfg80211 */
720 local->scan_req = req;
728 * Avoid re-scheduling when the sdata is going away.
730 if (!ieee80211_sdata_running(sdata)) {
736 * as long as no delay is required advance immediately
737 * without scheduling a new work
740 if (!ieee80211_sdata_running(sdata)) {
745 switch (local->next_scan_state) {
747 /* if no more bands/channels left, complete scan */
748 if (local->scan_channel_idx >= local->scan_req->n_channels) {
752 ieee80211_scan_state_decision(local, &next_delay);
754 case SCAN_SET_CHANNEL:
755 ieee80211_scan_state_set_channel(local, &next_delay);
757 case SCAN_SEND_PROBE:
758 ieee80211_scan_state_send_probe(local, &next_delay);
761 ieee80211_scan_state_suspend(local, &next_delay);
764 ieee80211_scan_state_resume(local, &next_delay);
770 } while (next_delay == 0);
772 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
776 hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
777 __ieee80211_scan_completed(&local->hw, aborted, hw_scan);
779 mutex_unlock(&local->mtx);
782 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
783 struct cfg80211_scan_request *req)
787 mutex_lock(&sdata->local->mtx);
788 res = __ieee80211_start_scan(sdata, req);
789 mutex_unlock(&sdata->local->mtx);
794 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
795 const u8 *ssid, u8 ssid_len,
796 struct ieee80211_channel *chan)
798 struct ieee80211_local *local = sdata->local;
800 enum ieee80211_band band;
802 mutex_lock(&local->mtx);
808 /* fill internal scan request */
813 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
814 if (!local->hw.wiphy->bands[band])
817 max_n = local->hw.wiphy->bands[band]->n_channels;
818 for (i = 0; i < max_n; i++) {
819 struct ieee80211_channel *tmp_ch =
820 &local->hw.wiphy->bands[band]->channels[i];
822 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IBSS |
823 IEEE80211_CHAN_DISABLED))
826 local->int_scan_req->channels[n_ch] = tmp_ch;
831 if (WARN_ON_ONCE(n_ch == 0))
834 local->int_scan_req->n_channels = n_ch;
836 if (WARN_ON_ONCE(chan->flags & (IEEE80211_CHAN_NO_IBSS |
837 IEEE80211_CHAN_DISABLED)))
840 local->int_scan_req->channels[0] = chan;
841 local->int_scan_req->n_channels = 1;
844 local->int_scan_req->ssids = &local->scan_ssid;
845 local->int_scan_req->n_ssids = 1;
846 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
847 local->int_scan_req->ssids[0].ssid_len = ssid_len;
849 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
851 mutex_unlock(&local->mtx);
856 * Only call this function when a scan can't be queued -- under RTNL.
858 void ieee80211_scan_cancel(struct ieee80211_local *local)
861 * We are canceling software scan, or deferred scan that was not
862 * yet really started (see __ieee80211_start_scan ).
864 * Regarding hardware scan:
865 * - we can not call __ieee80211_scan_completed() as when
866 * SCAN_HW_SCANNING bit is set this function change
867 * local->hw_scan_req to operate on 5G band, what race with
868 * driver which can use local->hw_scan_req
870 * - we can not cancel scan_work since driver can schedule it
871 * by ieee80211_scan_completed(..., true) to finish scan
873 * Hence we only call the cancel_hw_scan() callback, but the low-level
874 * driver is still responsible for calling ieee80211_scan_completed()
875 * after the scan was completed/aborted.
878 mutex_lock(&local->mtx);
879 if (!local->scan_req)
882 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
883 if (local->ops->cancel_hw_scan)
884 drv_cancel_hw_scan(local,
885 rcu_dereference_protected(local->scan_sdata,
886 lockdep_is_held(&local->mtx)));
891 * If the work is currently running, it must be blocked on
892 * the mutex, but we'll set scan_sdata = NULL and it'll
893 * simply exit once it acquires the mutex.
895 cancel_delayed_work(&local->scan_work);
897 __ieee80211_scan_completed(&local->hw, true, false);
899 mutex_unlock(&local->mtx);
902 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
903 struct cfg80211_sched_scan_request *req)
905 struct ieee80211_local *local = sdata->local;
906 struct ieee80211_sched_scan_ies sched_scan_ies = {};
909 iebufsz = 2 + IEEE80211_MAX_SSID_LEN +
910 local->scan_ies_len + req->ie_len;
912 mutex_lock(&local->mtx);
914 if (rcu_access_pointer(local->sched_scan_sdata)) {
919 if (!local->ops->sched_scan_start) {
924 for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
925 if (!local->hw.wiphy->bands[i])
928 sched_scan_ies.ie[i] = kzalloc(iebufsz, GFP_KERNEL);
929 if (!sched_scan_ies.ie[i]) {
934 sched_scan_ies.len[i] =
935 ieee80211_build_preq_ies(local, sched_scan_ies.ie[i],
936 iebufsz, req->ie, req->ie_len,
940 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
942 rcu_assign_pointer(local->sched_scan_sdata, sdata);
946 kfree(sched_scan_ies.ie[--i]);
948 mutex_unlock(&local->mtx);
952 int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata)
954 struct ieee80211_local *local = sdata->local;
957 mutex_lock(&local->mtx);
959 if (!local->ops->sched_scan_stop) {
964 if (rcu_access_pointer(local->sched_scan_sdata))
965 drv_sched_scan_stop(local, sdata);
968 mutex_unlock(&local->mtx);
973 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
975 struct ieee80211_local *local = hw_to_local(hw);
977 trace_api_sched_scan_results(local);
979 cfg80211_sched_scan_results(hw->wiphy);
981 EXPORT_SYMBOL(ieee80211_sched_scan_results);
983 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
985 struct ieee80211_local *local =
986 container_of(work, struct ieee80211_local,
987 sched_scan_stopped_work);
989 mutex_lock(&local->mtx);
991 if (!rcu_access_pointer(local->sched_scan_sdata)) {
992 mutex_unlock(&local->mtx);
996 rcu_assign_pointer(local->sched_scan_sdata, NULL);
998 mutex_unlock(&local->mtx);
1000 cfg80211_sched_scan_stopped(local->hw.wiphy);
1003 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1005 struct ieee80211_local *local = hw_to_local(hw);
1007 trace_api_sched_scan_stopped(local);
1009 ieee80211_queue_work(&local->hw, &local->sched_scan_stopped_work);
1011 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);