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 / 8)
32 static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss)
34 struct ieee80211_bss *bss = (void *)cbss->priv;
36 kfree(bss_mesh_id(bss));
37 kfree(bss_mesh_cfg(bss));
40 void ieee80211_rx_bss_put(struct ieee80211_local *local,
41 struct ieee80211_bss *bss)
45 cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv));
48 static bool is_uapsd_supported(struct ieee802_11_elems *elems)
52 if (elems->wmm_info && elems->wmm_info_len == 7
53 && elems->wmm_info[5] == 1)
54 qos_info = elems->wmm_info[6];
55 else if (elems->wmm_param && elems->wmm_param_len == 24
56 && elems->wmm_param[5] == 1)
57 qos_info = elems->wmm_param[6];
59 /* no valid wmm information or parameter element found */
62 return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
65 struct ieee80211_bss *
66 ieee80211_bss_info_update(struct ieee80211_local *local,
67 struct ieee80211_rx_status *rx_status,
68 struct ieee80211_mgmt *mgmt,
70 struct ieee802_11_elems *elems,
71 struct ieee80211_channel *channel,
74 struct cfg80211_bss *cbss;
75 struct ieee80211_bss *bss;
79 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
80 signal = rx_status->signal * 100;
81 else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
82 signal = (rx_status->signal * 100) / local->hw.max_signal;
84 cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel,
85 mgmt, len, signal, GFP_ATOMIC);
90 cbss->free_priv = ieee80211_rx_bss_free;
91 bss = (void *)cbss->priv;
93 if (elems->parse_error) {
95 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
97 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
100 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
102 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
105 /* save the ERP value so that it is available at association time */
106 if (elems->erp_info && elems->erp_info_len >= 1 &&
107 (!elems->parse_error ||
108 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
109 bss->erp_value = elems->erp_info[0];
110 bss->has_erp_value = true;
111 if (!elems->parse_error)
112 bss->valid_data |= IEEE80211_BSS_VALID_ERP;
115 if (elems->tim && (!elems->parse_error ||
116 !(bss->valid_data & IEEE80211_BSS_VALID_DTIM))) {
117 struct ieee80211_tim_ie *tim_ie =
118 (struct ieee80211_tim_ie *)elems->tim;
119 bss->dtim_period = tim_ie->dtim_period;
120 if (!elems->parse_error)
121 bss->valid_data |= IEEE80211_BSS_VALID_DTIM;
124 /* If the beacon had no TIM IE, or it was invalid, use 1 */
125 if (beacon && !bss->dtim_period)
126 bss->dtim_period = 1;
128 /* replace old supported rates if we get new values */
129 if (!elems->parse_error ||
130 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
132 if (elems->supp_rates) {
133 clen = IEEE80211_MAX_SUPP_RATES;
134 if (clen > elems->supp_rates_len)
135 clen = elems->supp_rates_len;
136 memcpy(bss->supp_rates, elems->supp_rates, clen);
139 if (elems->ext_supp_rates) {
140 clen = IEEE80211_MAX_SUPP_RATES - srlen;
141 if (clen > elems->ext_supp_rates_len)
142 clen = elems->ext_supp_rates_len;
143 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
148 bss->supp_rates_len = srlen;
149 if (!elems->parse_error)
150 bss->valid_data |= IEEE80211_BSS_VALID_RATES;
154 if (!elems->parse_error ||
155 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
156 bss->wmm_used = elems->wmm_param || elems->wmm_info;
157 bss->uapsd_supported = is_uapsd_supported(elems);
158 if (!elems->parse_error)
159 bss->valid_data |= IEEE80211_BSS_VALID_WMM;
163 bss->last_probe_resp = jiffies;
169 ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
171 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
172 struct ieee80211_mgmt *mgmt;
173 struct ieee80211_bss *bss;
175 struct ieee80211_channel *channel;
179 bool presp, beacon = false;
180 struct ieee802_11_elems elems;
183 return RX_DROP_UNUSABLE;
185 mgmt = (struct ieee80211_mgmt *) skb->data;
186 fc = mgmt->frame_control;
188 if (ieee80211_is_ctl(fc))
194 presp = ieee80211_is_probe_resp(fc);
196 /* ignore ProbeResp to foreign address */
197 if (!ether_addr_equal(mgmt->da, sdata->vif.addr))
198 return RX_DROP_MONITOR;
201 elements = mgmt->u.probe_resp.variable;
202 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
204 beacon = ieee80211_is_beacon(fc);
205 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
206 elements = mgmt->u.beacon.variable;
209 if (!presp && !beacon)
212 if (baselen > skb->len)
213 return RX_DROP_MONITOR;
215 ieee802_11_parse_elems(elements, skb->len - baselen, &elems);
217 if (elems.ds_params && elems.ds_params_len == 1)
218 freq = ieee80211_channel_to_frequency(elems.ds_params[0],
221 freq = rx_status->freq;
223 channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
225 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
226 return RX_DROP_MONITOR;
228 bss = ieee80211_bss_info_update(sdata->local, rx_status,
229 mgmt, skb->len, &elems,
232 ieee80211_rx_bss_put(sdata->local, bss);
234 if (channel == sdata->local->oper_channel)
241 /* return false if no more work */
242 static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
244 struct cfg80211_scan_request *req = local->scan_req;
245 enum ieee80211_band band;
246 int i, ielen, n_chans;
249 if (local->hw_scan_band == IEEE80211_NUM_BANDS)
252 band = local->hw_scan_band;
254 for (i = 0; i < req->n_channels; i++) {
255 if (req->channels[i]->band == band) {
256 local->hw_scan_req->channels[n_chans] =
262 local->hw_scan_band++;
265 local->hw_scan_req->n_channels = n_chans;
267 ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie,
268 req->ie, req->ie_len, band,
269 req->rates[band], 0);
270 local->hw_scan_req->ie_len = ielen;
271 local->hw_scan_req->no_cck = req->no_cck;
276 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted,
279 struct ieee80211_local *local = hw_to_local(hw);
281 lockdep_assert_held(&local->mtx);
284 * It's ok to abort a not-yet-running scan (that
285 * we have one at all will be verified by checking
286 * local->scan_req next), but not to complete it
289 if (WARN_ON(!local->scanning && !aborted))
292 if (WARN_ON(!local->scan_req))
295 if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) {
298 rc = drv_hw_scan(local,
299 rcu_dereference_protected(local->scan_sdata,
300 lockdep_is_held(&local->mtx)),
307 kfree(local->hw_scan_req);
308 local->hw_scan_req = NULL;
310 if (local->scan_req != local->int_scan_req)
311 cfg80211_scan_done(local->scan_req, aborted);
312 local->scan_req = NULL;
313 local->scan_sdata = NULL;
316 local->scan_channel = NULL;
318 /* Set power back to normal operating levels. */
319 ieee80211_hw_config(local, 0);
322 ieee80211_configure_filter(local);
323 drv_sw_scan_complete(local);
324 ieee80211_offchannel_return(local, true);
327 ieee80211_recalc_idle(local);
329 ieee80211_mlme_notify_scan_completed(local);
330 ieee80211_ibss_notify_scan_completed(local);
331 ieee80211_mesh_notify_scan_completed(local);
332 ieee80211_start_next_roc(local);
335 void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
337 struct ieee80211_local *local = hw_to_local(hw);
339 trace_api_scan_completed(local, aborted);
341 set_bit(SCAN_COMPLETED, &local->scanning);
343 set_bit(SCAN_ABORTED, &local->scanning);
344 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
346 EXPORT_SYMBOL(ieee80211_scan_completed);
348 static int ieee80211_start_sw_scan(struct ieee80211_local *local)
351 * Hardware/driver doesn't support hw_scan, so use software
352 * scanning instead. First send a nullfunc frame with power save
353 * bit on so that AP will buffer the frames for us while we are not
354 * listening, then send probe requests to each channel and wait for
355 * the responses. After all channels are scanned, tune back to the
356 * original channel and send a nullfunc frame with power save bit
357 * off to trigger the AP to send us all the buffered frames.
359 * Note that while local->sw_scanning is true everything else but
360 * nullfunc frames and probe requests will be dropped in
361 * ieee80211_tx_h_check_assoc().
363 drv_sw_scan_start(local);
365 local->leave_oper_channel_time = jiffies;
366 local->next_scan_state = SCAN_DECISION;
367 local->scan_channel_idx = 0;
369 ieee80211_offchannel_stop_vifs(local, true);
371 ieee80211_configure_filter(local);
373 /* We need to set power level at maximum rate for scanning. */
374 ieee80211_hw_config(local, 0);
376 ieee80211_queue_delayed_work(&local->hw,
377 &local->scan_work, 0);
382 static bool ieee80211_can_scan(struct ieee80211_local *local,
383 struct ieee80211_sub_if_data *sdata)
385 if (!list_empty(&local->roc_list))
388 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
389 sdata->u.mgd.flags & (IEEE80211_STA_BEACON_POLL |
390 IEEE80211_STA_CONNECTION_POLL))
396 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
398 lockdep_assert_held(&local->mtx);
400 if (!local->scan_req || local->scanning)
403 if (!ieee80211_can_scan(local,
404 rcu_dereference_protected(
406 lockdep_is_held(&local->mtx))))
409 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
410 round_jiffies_relative(0));
413 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
414 unsigned long *next_delay)
417 struct ieee80211_sub_if_data *sdata;
418 enum ieee80211_band band = local->hw.conf.channel->band;
420 sdata = rcu_dereference_protected(local->scan_sdata,
421 lockdep_is_held(&local->mtx));;
423 for (i = 0; i < local->scan_req->n_ssids; i++)
424 ieee80211_send_probe_req(
426 local->scan_req->ssids[i].ssid,
427 local->scan_req->ssids[i].ssid_len,
428 local->scan_req->ie, local->scan_req->ie_len,
429 local->scan_req->rates[band], false,
430 local->scan_req->no_cck);
433 * After sending probe requests, wait for probe responses
436 *next_delay = IEEE80211_CHANNEL_TIME;
437 local->next_scan_state = SCAN_DECISION;
440 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
441 struct cfg80211_scan_request *req)
443 struct ieee80211_local *local = sdata->local;
446 lockdep_assert_held(&local->mtx);
451 if (!ieee80211_can_scan(local, sdata)) {
452 /* wait for the work to finish/time out */
453 local->scan_req = req;
454 rcu_assign_pointer(local->scan_sdata, sdata);
458 if (local->ops->hw_scan) {
461 local->hw_scan_req = kmalloc(
462 sizeof(*local->hw_scan_req) +
463 req->n_channels * sizeof(req->channels[0]) +
464 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len +
465 req->ie_len, GFP_KERNEL);
466 if (!local->hw_scan_req)
469 local->hw_scan_req->ssids = req->ssids;
470 local->hw_scan_req->n_ssids = req->n_ssids;
471 ies = (u8 *)local->hw_scan_req +
472 sizeof(*local->hw_scan_req) +
473 req->n_channels * sizeof(req->channels[0]);
474 local->hw_scan_req->ie = ies;
476 local->hw_scan_band = 0;
479 * After allocating local->hw_scan_req, we must
480 * go through until ieee80211_prep_hw_scan(), so
481 * anything that might be changed here and leave
482 * this function early must not go after this
487 local->scan_req = req;
488 rcu_assign_pointer(local->scan_sdata, sdata);
490 if (local->ops->hw_scan) {
491 __set_bit(SCAN_HW_SCANNING, &local->scanning);
492 } else if ((req->n_channels == 1) &&
493 (req->channels[0]->center_freq ==
494 local->hw.conf.channel->center_freq)) {
496 /* If we are scanning only on the current channel, then
497 * we do not need to stop normal activities
499 unsigned long next_delay;
501 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
503 ieee80211_recalc_idle(local);
505 /* Notify driver scan is starting, keep order of operations
506 * same as normal software scan, in case that matters. */
507 drv_sw_scan_start(local);
509 ieee80211_configure_filter(local); /* accept probe-responses */
511 /* We need to ensure power level is at max for scanning. */
512 ieee80211_hw_config(local, 0);
514 if ((req->channels[0]->flags &
515 IEEE80211_CHAN_PASSIVE_SCAN) ||
516 !local->scan_req->n_ssids) {
517 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
519 ieee80211_scan_state_send_probe(local, &next_delay);
520 next_delay = IEEE80211_CHANNEL_TIME;
523 /* Now, just wait a bit and we are all done! */
524 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
528 /* Do normal software scan */
529 __set_bit(SCAN_SW_SCANNING, &local->scanning);
532 ieee80211_recalc_idle(local);
534 if (local->ops->hw_scan) {
535 WARN_ON(!ieee80211_prep_hw_scan(local));
536 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
538 rc = ieee80211_start_sw_scan(local);
541 kfree(local->hw_scan_req);
542 local->hw_scan_req = NULL;
545 ieee80211_recalc_idle(local);
547 local->scan_req = NULL;
548 rcu_assign_pointer(local->scan_sdata, NULL);
555 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
558 * TODO: channel switching also consumes quite some time,
559 * add that delay as well to get a better estimation
561 if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN)
562 return IEEE80211_PASSIVE_CHANNEL_TIME;
563 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
566 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
567 unsigned long *next_delay)
569 bool associated = false;
570 bool tx_empty = true;
572 bool listen_int_exceeded;
573 unsigned long min_beacon_int = 0;
574 struct ieee80211_sub_if_data *sdata;
575 struct ieee80211_channel *next_chan;
578 * check if at least one STA interface is associated,
579 * check if at least one STA interface has pending tx frames
580 * and grab the lowest used beacon interval
582 mutex_lock(&local->iflist_mtx);
583 list_for_each_entry(sdata, &local->interfaces, list) {
584 if (!ieee80211_sdata_running(sdata))
587 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
588 if (sdata->u.mgd.associated) {
591 if (sdata->vif.bss_conf.beacon_int <
592 min_beacon_int || min_beacon_int == 0)
594 sdata->vif.bss_conf.beacon_int;
596 if (!qdisc_all_tx_empty(sdata->dev)) {
603 mutex_unlock(&local->iflist_mtx);
605 next_chan = local->scan_req->channels[local->scan_channel_idx];
608 * we're currently scanning a different channel, let's
609 * see if we can scan another channel without interfering
610 * with the current traffic situation.
612 * Since we don't know if the AP has pending frames for us
613 * we can only check for our tx queues and use the current
614 * pm_qos requirements for rx. Hence, if no tx traffic occurs
615 * at all we will scan as many channels in a row as the pm_qos
616 * latency allows us to. Additionally we also check for the
617 * currently negotiated listen interval to prevent losing
618 * frames unnecessarily.
620 * Otherwise switch back to the operating channel.
623 bad_latency = time_after(jiffies +
624 ieee80211_scan_get_channel_time(next_chan),
625 local->leave_oper_channel_time +
626 usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY)));
628 listen_int_exceeded = time_after(jiffies +
629 ieee80211_scan_get_channel_time(next_chan),
630 local->leave_oper_channel_time +
631 usecs_to_jiffies(min_beacon_int * 1024) *
632 local->hw.conf.listen_interval);
634 if (associated && (!tx_empty || bad_latency || listen_int_exceeded))
635 local->next_scan_state = SCAN_SUSPEND;
637 local->next_scan_state = SCAN_SET_CHANNEL;
642 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
643 unsigned long *next_delay)
646 struct ieee80211_channel *chan;
649 chan = local->scan_req->channels[local->scan_channel_idx];
651 local->scan_channel = chan;
653 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
656 /* advance state machine to next channel/band */
657 local->scan_channel_idx++;
660 /* if we skip this channel return to the decision state */
661 local->next_scan_state = SCAN_DECISION;
666 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
667 * (which unfortunately doesn't say _why_ step a) is done,
668 * but it waits for the probe delay or until a frame is
669 * received - and the received frame would update the NAV).
670 * For now, we do not support waiting until a frame is
673 * In any case, it is not necessary for a passive scan.
675 if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
676 !local->scan_req->n_ssids) {
677 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
678 local->next_scan_state = SCAN_DECISION;
682 /* active scan, send probes */
683 *next_delay = IEEE80211_PROBE_DELAY;
684 local->next_scan_state = SCAN_SEND_PROBE;
687 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
688 unsigned long *next_delay)
690 /* switch back to the operating channel */
691 local->scan_channel = NULL;
692 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
695 * Re-enable vifs and beaconing. Leave PS
696 * in off-channel state..will put that back
697 * on-channel at the end of scanning.
699 ieee80211_offchannel_return(local, false);
701 *next_delay = HZ / 5;
702 /* afterwards, resume scan & go to next channel */
703 local->next_scan_state = SCAN_RESUME;
706 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
707 unsigned long *next_delay)
709 /* PS already is in off-channel mode */
710 ieee80211_offchannel_stop_vifs(local, false);
712 if (local->ops->flush) {
713 drv_flush(local, false);
716 *next_delay = HZ / 10;
718 /* remember when we left the operating channel */
719 local->leave_oper_channel_time = jiffies;
721 /* advance to the next channel to be scanned */
722 local->next_scan_state = SCAN_SET_CHANNEL;
725 void ieee80211_scan_work(struct work_struct *work)
727 struct ieee80211_local *local =
728 container_of(work, struct ieee80211_local, scan_work.work);
729 struct ieee80211_sub_if_data *sdata;
730 unsigned long next_delay = 0;
731 bool aborted, hw_scan;
733 mutex_lock(&local->mtx);
735 sdata = rcu_dereference_protected(local->scan_sdata,
736 lockdep_is_held(&local->mtx));
738 /* When scanning on-channel, the first-callback means completed. */
739 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
740 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
744 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
745 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
749 if (!sdata || !local->scan_req)
752 if (local->scan_req && !local->scanning) {
753 struct cfg80211_scan_request *req = local->scan_req;
756 local->scan_req = NULL;
757 rcu_assign_pointer(local->scan_sdata, NULL);
759 rc = __ieee80211_start_scan(sdata, req);
761 /* need to complete scan in cfg80211 */
762 local->scan_req = req;
770 * Avoid re-scheduling when the sdata is going away.
772 if (!ieee80211_sdata_running(sdata)) {
778 * as long as no delay is required advance immediately
779 * without scheduling a new work
782 if (!ieee80211_sdata_running(sdata)) {
787 switch (local->next_scan_state) {
789 /* if no more bands/channels left, complete scan */
790 if (local->scan_channel_idx >= local->scan_req->n_channels) {
794 ieee80211_scan_state_decision(local, &next_delay);
796 case SCAN_SET_CHANNEL:
797 ieee80211_scan_state_set_channel(local, &next_delay);
799 case SCAN_SEND_PROBE:
800 ieee80211_scan_state_send_probe(local, &next_delay);
803 ieee80211_scan_state_suspend(local, &next_delay);
806 ieee80211_scan_state_resume(local, &next_delay);
809 } while (next_delay == 0);
811 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
815 hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
816 __ieee80211_scan_completed(&local->hw, aborted, hw_scan);
818 mutex_unlock(&local->mtx);
821 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
822 struct cfg80211_scan_request *req)
826 mutex_lock(&sdata->local->mtx);
827 res = __ieee80211_start_scan(sdata, req);
828 mutex_unlock(&sdata->local->mtx);
833 int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata,
834 const u8 *ssid, u8 ssid_len,
835 struct ieee80211_channel *chan)
837 struct ieee80211_local *local = sdata->local;
839 enum ieee80211_band band;
841 mutex_lock(&local->mtx);
847 /* fill internal scan request */
851 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
852 if (!local->hw.wiphy->bands[band])
855 i < local->hw.wiphy->bands[band]->n_channels;
857 local->int_scan_req->channels[nchan] =
858 &local->hw.wiphy->bands[band]->channels[i];
863 local->int_scan_req->n_channels = nchan;
865 local->int_scan_req->channels[0] = chan;
866 local->int_scan_req->n_channels = 1;
869 local->int_scan_req->ssids = &local->scan_ssid;
870 local->int_scan_req->n_ssids = 1;
871 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
872 local->int_scan_req->ssids[0].ssid_len = ssid_len;
874 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
876 mutex_unlock(&local->mtx);
881 * Only call this function when a scan can't be queued -- under RTNL.
883 void ieee80211_scan_cancel(struct ieee80211_local *local)
886 * We are canceling software scan, or deferred scan that was not
887 * yet really started (see __ieee80211_start_scan ).
889 * Regarding hardware scan:
890 * - we can not call __ieee80211_scan_completed() as when
891 * SCAN_HW_SCANNING bit is set this function change
892 * local->hw_scan_req to operate on 5G band, what race with
893 * driver which can use local->hw_scan_req
895 * - we can not cancel scan_work since driver can schedule it
896 * by ieee80211_scan_completed(..., true) to finish scan
898 * Hence we only call the cancel_hw_scan() callback, but the low-level
899 * driver is still responsible for calling ieee80211_scan_completed()
900 * after the scan was completed/aborted.
903 mutex_lock(&local->mtx);
904 if (!local->scan_req)
907 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
908 if (local->ops->cancel_hw_scan)
909 drv_cancel_hw_scan(local,
910 rcu_dereference_protected(local->scan_sdata,
911 lockdep_is_held(&local->mtx)));
916 * If the work is currently running, it must be blocked on
917 * the mutex, but we'll set scan_sdata = NULL and it'll
918 * simply exit once it acquires the mutex.
920 cancel_delayed_work(&local->scan_work);
922 __ieee80211_scan_completed(&local->hw, true, false);
924 mutex_unlock(&local->mtx);
927 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
928 struct cfg80211_sched_scan_request *req)
930 struct ieee80211_local *local = sdata->local;
933 mutex_lock(&sdata->local->mtx);
935 if (local->sched_scanning) {
940 if (!local->ops->sched_scan_start) {
945 for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
946 if (!local->hw.wiphy->bands[i])
949 local->sched_scan_ies.ie[i] = kzalloc(2 +
950 IEEE80211_MAX_SSID_LEN +
951 local->scan_ies_len +
954 if (!local->sched_scan_ies.ie[i]) {
959 local->sched_scan_ies.len[i] =
960 ieee80211_build_preq_ies(local,
961 local->sched_scan_ies.ie[i],
962 req->ie, req->ie_len, i,
966 ret = drv_sched_scan_start(local, sdata, req,
967 &local->sched_scan_ies);
969 local->sched_scanning = true;
975 kfree(local->sched_scan_ies.ie[--i]);
977 mutex_unlock(&sdata->local->mtx);
981 int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata)
983 struct ieee80211_local *local = sdata->local;
986 mutex_lock(&sdata->local->mtx);
988 if (!local->ops->sched_scan_stop) {
993 if (local->sched_scanning) {
994 for (i = 0; i < IEEE80211_NUM_BANDS; i++)
995 kfree(local->sched_scan_ies.ie[i]);
997 drv_sched_scan_stop(local, sdata);
998 local->sched_scanning = false;
1001 mutex_unlock(&sdata->local->mtx);
1006 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1008 struct ieee80211_local *local = hw_to_local(hw);
1010 trace_api_sched_scan_results(local);
1012 cfg80211_sched_scan_results(hw->wiphy);
1014 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1016 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1018 struct ieee80211_local *local =
1019 container_of(work, struct ieee80211_local,
1020 sched_scan_stopped_work);
1023 mutex_lock(&local->mtx);
1025 if (!local->sched_scanning) {
1026 mutex_unlock(&local->mtx);
1030 for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1031 kfree(local->sched_scan_ies.ie[i]);
1033 local->sched_scanning = false;
1035 mutex_unlock(&local->mtx);
1037 cfg80211_sched_scan_stopped(local->hw.wiphy);
1040 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1042 struct ieee80211_local *local = hw_to_local(hw);
1044 trace_api_sched_scan_stopped(local);
1046 ieee80211_queue_work(&local->hw, &local->sched_scan_stopped_work);
1048 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);