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
);
89 cbss
->free_priv
= ieee80211_rx_bss_free
;
90 bss
= (void *)cbss
->priv
;
92 bss
->device_ts
= rx_status
->device_timestamp
;
94 if (elems
->parse_error
) {
96 bss
->corrupt_data
|= IEEE80211_BSS_CORRUPT_BEACON
;
98 bss
->corrupt_data
|= IEEE80211_BSS_CORRUPT_PROBE_RESP
;
101 bss
->corrupt_data
&= ~IEEE80211_BSS_CORRUPT_BEACON
;
103 bss
->corrupt_data
&= ~IEEE80211_BSS_CORRUPT_PROBE_RESP
;
106 /* save the ERP value so that it is available at association time */
107 if (elems
->erp_info
&& elems
->erp_info_len
>= 1 &&
108 (!elems
->parse_error
||
109 !(bss
->valid_data
& IEEE80211_BSS_VALID_ERP
))) {
110 bss
->erp_value
= elems
->erp_info
[0];
111 bss
->has_erp_value
= true;
112 if (!elems
->parse_error
)
113 bss
->valid_data
|= IEEE80211_BSS_VALID_ERP
;
116 if (elems
->tim
&& (!elems
->parse_error
||
117 !(bss
->valid_data
& IEEE80211_BSS_VALID_DTIM
))) {
118 struct ieee80211_tim_ie
*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
;
168 void ieee80211_scan_rx(struct ieee80211_local
*local
, struct sk_buff
*skb
)
170 struct ieee80211_rx_status
*rx_status
= IEEE80211_SKB_RXCB(skb
);
171 struct ieee80211_sub_if_data
*sdata1
, *sdata2
;
172 struct ieee80211_mgmt
*mgmt
= (void *)skb
->data
;
173 struct ieee80211_bss
*bss
;
175 struct ieee80211_channel
*channel
;
178 struct ieee802_11_elems elems
;
181 (!ieee80211_is_probe_resp(mgmt
->frame_control
) &&
182 !ieee80211_is_beacon(mgmt
->frame_control
)))
185 sdata1
= rcu_dereference(local
->scan_sdata
);
186 sdata2
= rcu_dereference(local
->sched_scan_sdata
);
188 if (likely(!sdata1
&& !sdata2
))
191 if (ieee80211_is_probe_resp(mgmt
->frame_control
)) {
192 /* ignore ProbeResp to foreign address */
193 if ((!sdata1
|| !ether_addr_equal(mgmt
->da
, sdata1
->vif
.addr
)) &&
194 (!sdata2
|| !ether_addr_equal(mgmt
->da
, sdata2
->vif
.addr
)))
197 elements
= mgmt
->u
.probe_resp
.variable
;
198 baselen
= offsetof(struct ieee80211_mgmt
, u
.probe_resp
.variable
);
201 baselen
= offsetof(struct ieee80211_mgmt
, u
.beacon
.variable
);
202 elements
= mgmt
->u
.beacon
.variable
;
206 if (baselen
> skb
->len
)
209 ieee802_11_parse_elems(elements
, skb
->len
- baselen
, &elems
);
211 channel
= ieee80211_get_channel(local
->hw
.wiphy
, rx_status
->freq
);
213 if (!channel
|| channel
->flags
& IEEE80211_CHAN_DISABLED
)
216 bss
= ieee80211_bss_info_update(local
, rx_status
,
217 mgmt
, skb
->len
, &elems
,
220 ieee80211_rx_bss_put(local
, bss
);
223 /* return false if no more work */
224 static bool ieee80211_prep_hw_scan(struct ieee80211_local
*local
)
226 struct cfg80211_scan_request
*req
= local
->scan_req
;
227 enum ieee80211_band band
;
228 int i
, ielen
, n_chans
;
231 if (local
->hw_scan_band
== IEEE80211_NUM_BANDS
)
234 band
= local
->hw_scan_band
;
236 for (i
= 0; i
< req
->n_channels
; i
++) {
237 if (req
->channels
[i
]->band
== band
) {
238 local
->hw_scan_req
->channels
[n_chans
] =
244 local
->hw_scan_band
++;
247 local
->hw_scan_req
->n_channels
= n_chans
;
249 ielen
= ieee80211_build_preq_ies(local
, (u8
*)local
->hw_scan_req
->ie
,
250 req
->ie
, req
->ie_len
, band
,
251 req
->rates
[band
], 0);
252 local
->hw_scan_req
->ie_len
= ielen
;
253 local
->hw_scan_req
->no_cck
= req
->no_cck
;
258 static void __ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
,
261 struct ieee80211_local
*local
= hw_to_local(hw
);
263 lockdep_assert_held(&local
->mtx
);
266 * It's ok to abort a not-yet-running scan (that
267 * we have one at all will be verified by checking
268 * local->scan_req next), but not to complete it
271 if (WARN_ON(!local
->scanning
&& !aborted
))
274 if (WARN_ON(!local
->scan_req
))
277 if (was_hw_scan
&& !aborted
&& ieee80211_prep_hw_scan(local
)) {
280 rc
= drv_hw_scan(local
,
281 rcu_dereference_protected(local
->scan_sdata
,
282 lockdep_is_held(&local
->mtx
)),
289 kfree(local
->hw_scan_req
);
290 local
->hw_scan_req
= NULL
;
292 if (local
->scan_req
!= local
->int_scan_req
)
293 cfg80211_scan_done(local
->scan_req
, aborted
);
294 local
->scan_req
= NULL
;
295 rcu_assign_pointer(local
->scan_sdata
, NULL
);
298 local
->scan_channel
= NULL
;
300 /* Set power back to normal operating levels. */
301 ieee80211_hw_config(local
, 0);
304 ieee80211_configure_filter(local
);
305 drv_sw_scan_complete(local
);
306 ieee80211_offchannel_return(local
, true);
309 ieee80211_recalc_idle(local
);
311 ieee80211_mlme_notify_scan_completed(local
);
312 ieee80211_ibss_notify_scan_completed(local
);
313 ieee80211_mesh_notify_scan_completed(local
);
314 ieee80211_start_next_roc(local
);
317 void ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
)
319 struct ieee80211_local
*local
= hw_to_local(hw
);
321 trace_api_scan_completed(local
, aborted
);
323 set_bit(SCAN_COMPLETED
, &local
->scanning
);
325 set_bit(SCAN_ABORTED
, &local
->scanning
);
326 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, 0);
328 EXPORT_SYMBOL(ieee80211_scan_completed
);
330 static int ieee80211_start_sw_scan(struct ieee80211_local
*local
)
332 /* Software scan is not supported in multi-channel cases */
333 if (local
->use_chanctx
)
337 * Hardware/driver doesn't support hw_scan, so use software
338 * scanning instead. First send a nullfunc frame with power save
339 * bit on so that AP will buffer the frames for us while we are not
340 * listening, then send probe requests to each channel and wait for
341 * the responses. After all channels are scanned, tune back to the
342 * original channel and send a nullfunc frame with power save bit
343 * off to trigger the AP to send us all the buffered frames.
345 * Note that while local->sw_scanning is true everything else but
346 * nullfunc frames and probe requests will be dropped in
347 * ieee80211_tx_h_check_assoc().
349 drv_sw_scan_start(local
);
351 local
->leave_oper_channel_time
= jiffies
;
352 local
->next_scan_state
= SCAN_DECISION
;
353 local
->scan_channel_idx
= 0;
355 ieee80211_offchannel_stop_vifs(local
, true);
357 ieee80211_configure_filter(local
);
359 /* We need to set power level at maximum rate for scanning. */
360 ieee80211_hw_config(local
, 0);
362 ieee80211_queue_delayed_work(&local
->hw
,
363 &local
->scan_work
, 0);
368 static bool ieee80211_can_scan(struct ieee80211_local
*local
,
369 struct ieee80211_sub_if_data
*sdata
)
371 if (!list_empty(&local
->roc_list
))
374 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
&&
375 sdata
->u
.mgd
.flags
& (IEEE80211_STA_BEACON_POLL
|
376 IEEE80211_STA_CONNECTION_POLL
))
382 void ieee80211_run_deferred_scan(struct ieee80211_local
*local
)
384 lockdep_assert_held(&local
->mtx
);
386 if (!local
->scan_req
|| local
->scanning
)
389 if (!ieee80211_can_scan(local
,
390 rcu_dereference_protected(
392 lockdep_is_held(&local
->mtx
))))
395 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
396 round_jiffies_relative(0));
399 static void ieee80211_scan_state_send_probe(struct ieee80211_local
*local
,
400 unsigned long *next_delay
)
403 struct ieee80211_sub_if_data
*sdata
;
404 enum ieee80211_band band
= local
->hw
.conf
.channel
->band
;
406 sdata
= rcu_dereference_protected(local
->scan_sdata
,
407 lockdep_is_held(&local
->mtx
));
409 for (i
= 0; i
< local
->scan_req
->n_ssids
; i
++)
410 ieee80211_send_probe_req(
412 local
->scan_req
->ssids
[i
].ssid
,
413 local
->scan_req
->ssids
[i
].ssid_len
,
414 local
->scan_req
->ie
, local
->scan_req
->ie_len
,
415 local
->scan_req
->rates
[band
], false,
416 local
->scan_req
->no_cck
,
417 local
->hw
.conf
.channel
, true);
420 * After sending probe requests, wait for probe responses
423 *next_delay
= IEEE80211_CHANNEL_TIME
;
424 local
->next_scan_state
= SCAN_DECISION
;
427 static int __ieee80211_start_scan(struct ieee80211_sub_if_data
*sdata
,
428 struct cfg80211_scan_request
*req
)
430 struct ieee80211_local
*local
= sdata
->local
;
433 lockdep_assert_held(&local
->mtx
);
438 if (!ieee80211_can_scan(local
, sdata
)) {
439 /* wait for the work to finish/time out */
440 local
->scan_req
= req
;
441 rcu_assign_pointer(local
->scan_sdata
, sdata
);
445 if (local
->ops
->hw_scan
) {
448 local
->hw_scan_req
= kmalloc(
449 sizeof(*local
->hw_scan_req
) +
450 req
->n_channels
* sizeof(req
->channels
[0]) +
451 2 + IEEE80211_MAX_SSID_LEN
+ local
->scan_ies_len
+
452 req
->ie_len
, GFP_KERNEL
);
453 if (!local
->hw_scan_req
)
456 local
->hw_scan_req
->ssids
= req
->ssids
;
457 local
->hw_scan_req
->n_ssids
= req
->n_ssids
;
458 ies
= (u8
*)local
->hw_scan_req
+
459 sizeof(*local
->hw_scan_req
) +
460 req
->n_channels
* sizeof(req
->channels
[0]);
461 local
->hw_scan_req
->ie
= ies
;
462 local
->hw_scan_req
->flags
= req
->flags
;
464 local
->hw_scan_band
= 0;
467 * After allocating local->hw_scan_req, we must
468 * go through until ieee80211_prep_hw_scan(), so
469 * anything that might be changed here and leave
470 * this function early must not go after this
475 local
->scan_req
= req
;
476 rcu_assign_pointer(local
->scan_sdata
, sdata
);
478 if (local
->ops
->hw_scan
) {
479 __set_bit(SCAN_HW_SCANNING
, &local
->scanning
);
480 } else if ((req
->n_channels
== 1) &&
481 (req
->channels
[0] == local
->_oper_channel
)) {
483 * If we are scanning only on the operating channel
484 * then we do not need to stop normal activities
486 unsigned long next_delay
;
488 __set_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
);
490 ieee80211_recalc_idle(local
);
492 /* Notify driver scan is starting, keep order of operations
493 * same as normal software scan, in case that matters. */
494 drv_sw_scan_start(local
);
496 ieee80211_configure_filter(local
); /* accept probe-responses */
498 /* We need to ensure power level is at max for scanning. */
499 ieee80211_hw_config(local
, 0);
501 if ((req
->channels
[0]->flags
&
502 IEEE80211_CHAN_PASSIVE_SCAN
) ||
503 !local
->scan_req
->n_ssids
) {
504 next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
506 ieee80211_scan_state_send_probe(local
, &next_delay
);
507 next_delay
= IEEE80211_CHANNEL_TIME
;
510 /* Now, just wait a bit and we are all done! */
511 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
515 /* Do normal software scan */
516 __set_bit(SCAN_SW_SCANNING
, &local
->scanning
);
519 ieee80211_recalc_idle(local
);
521 if (local
->ops
->hw_scan
) {
522 WARN_ON(!ieee80211_prep_hw_scan(local
));
523 rc
= drv_hw_scan(local
, sdata
, local
->hw_scan_req
);
525 rc
= ieee80211_start_sw_scan(local
);
528 kfree(local
->hw_scan_req
);
529 local
->hw_scan_req
= NULL
;
532 ieee80211_recalc_idle(local
);
534 local
->scan_req
= NULL
;
535 rcu_assign_pointer(local
->scan_sdata
, NULL
);
542 ieee80211_scan_get_channel_time(struct ieee80211_channel
*chan
)
545 * TODO: channel switching also consumes quite some time,
546 * add that delay as well to get a better estimation
548 if (chan
->flags
& IEEE80211_CHAN_PASSIVE_SCAN
)
549 return IEEE80211_PASSIVE_CHANNEL_TIME
;
550 return IEEE80211_PROBE_DELAY
+ IEEE80211_CHANNEL_TIME
;
553 static void ieee80211_scan_state_decision(struct ieee80211_local
*local
,
554 unsigned long *next_delay
)
556 bool associated
= false;
557 bool tx_empty
= true;
559 bool listen_int_exceeded
;
560 unsigned long min_beacon_int
= 0;
561 struct ieee80211_sub_if_data
*sdata
;
562 struct ieee80211_channel
*next_chan
;
563 enum mac80211_scan_state next_scan_state
;
566 * check if at least one STA interface is associated,
567 * check if at least one STA interface has pending tx frames
568 * and grab the lowest used beacon interval
570 mutex_lock(&local
->iflist_mtx
);
571 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
572 if (!ieee80211_sdata_running(sdata
))
575 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
576 if (sdata
->u
.mgd
.associated
) {
579 if (sdata
->vif
.bss_conf
.beacon_int
<
580 min_beacon_int
|| min_beacon_int
== 0)
582 sdata
->vif
.bss_conf
.beacon_int
;
584 if (!qdisc_all_tx_empty(sdata
->dev
)) {
591 mutex_unlock(&local
->iflist_mtx
);
593 next_chan
= local
->scan_req
->channels
[local
->scan_channel_idx
];
596 * we're currently scanning a different channel, let's
597 * see if we can scan another channel without interfering
598 * with the current traffic situation.
600 * Since we don't know if the AP has pending frames for us
601 * we can only check for our tx queues and use the current
602 * pm_qos requirements for rx. Hence, if no tx traffic occurs
603 * at all we will scan as many channels in a row as the pm_qos
604 * latency allows us to. Additionally we also check for the
605 * currently negotiated listen interval to prevent losing
606 * frames unnecessarily.
608 * Otherwise switch back to the operating channel.
611 bad_latency
= time_after(jiffies
+
612 ieee80211_scan_get_channel_time(next_chan
),
613 local
->leave_oper_channel_time
+
614 usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY
)));
616 listen_int_exceeded
= time_after(jiffies
+
617 ieee80211_scan_get_channel_time(next_chan
),
618 local
->leave_oper_channel_time
+
619 usecs_to_jiffies(min_beacon_int
* 1024) *
620 local
->hw
.conf
.listen_interval
);
622 if (associated
&& !tx_empty
) {
623 if (local
->scan_req
->flags
& NL80211_SCAN_FLAG_LOW_PRIORITY
)
624 next_scan_state
= SCAN_ABORT
;
626 next_scan_state
= SCAN_SUSPEND
;
627 } else if (associated
&& (bad_latency
|| listen_int_exceeded
)) {
628 next_scan_state
= SCAN_SUSPEND
;
630 next_scan_state
= SCAN_SET_CHANNEL
;
633 local
->next_scan_state
= next_scan_state
;
638 static void ieee80211_scan_state_set_channel(struct ieee80211_local
*local
,
639 unsigned long *next_delay
)
642 struct ieee80211_channel
*chan
;
645 chan
= local
->scan_req
->channels
[local
->scan_channel_idx
];
647 local
->scan_channel
= chan
;
649 if (ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
))
652 /* advance state machine to next channel/band */
653 local
->scan_channel_idx
++;
656 /* if we skip this channel return to the decision state */
657 local
->next_scan_state
= SCAN_DECISION
;
662 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
663 * (which unfortunately doesn't say _why_ step a) is done,
664 * but it waits for the probe delay or until a frame is
665 * received - and the received frame would update the NAV).
666 * For now, we do not support waiting until a frame is
669 * In any case, it is not necessary for a passive scan.
671 if (chan
->flags
& IEEE80211_CHAN_PASSIVE_SCAN
||
672 !local
->scan_req
->n_ssids
) {
673 *next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
674 local
->next_scan_state
= SCAN_DECISION
;
678 /* active scan, send probes */
679 *next_delay
= IEEE80211_PROBE_DELAY
;
680 local
->next_scan_state
= SCAN_SEND_PROBE
;
683 static void ieee80211_scan_state_suspend(struct ieee80211_local
*local
,
684 unsigned long *next_delay
)
686 /* switch back to the operating channel */
687 local
->scan_channel
= NULL
;
688 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
691 * Re-enable vifs and beaconing. Leave PS
692 * in off-channel state..will put that back
693 * on-channel at the end of scanning.
695 ieee80211_offchannel_return(local
, false);
697 *next_delay
= HZ
/ 5;
698 /* afterwards, resume scan & go to next channel */
699 local
->next_scan_state
= SCAN_RESUME
;
702 static void ieee80211_scan_state_resume(struct ieee80211_local
*local
,
703 unsigned long *next_delay
)
705 /* PS already is in off-channel mode */
706 ieee80211_offchannel_stop_vifs(local
, false);
708 if (local
->ops
->flush
) {
709 drv_flush(local
, false);
712 *next_delay
= HZ
/ 10;
714 /* remember when we left the operating channel */
715 local
->leave_oper_channel_time
= jiffies
;
717 /* advance to the next channel to be scanned */
718 local
->next_scan_state
= SCAN_SET_CHANNEL
;
721 void ieee80211_scan_work(struct work_struct
*work
)
723 struct ieee80211_local
*local
=
724 container_of(work
, struct ieee80211_local
, scan_work
.work
);
725 struct ieee80211_sub_if_data
*sdata
;
726 unsigned long next_delay
= 0;
727 bool aborted
, hw_scan
;
729 mutex_lock(&local
->mtx
);
731 sdata
= rcu_dereference_protected(local
->scan_sdata
,
732 lockdep_is_held(&local
->mtx
));
734 /* When scanning on-channel, the first-callback means completed. */
735 if (test_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
)) {
736 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
740 if (test_and_clear_bit(SCAN_COMPLETED
, &local
->scanning
)) {
741 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
745 if (!sdata
|| !local
->scan_req
)
748 if (local
->scan_req
&& !local
->scanning
) {
749 struct cfg80211_scan_request
*req
= local
->scan_req
;
752 local
->scan_req
= NULL
;
753 rcu_assign_pointer(local
->scan_sdata
, NULL
);
755 rc
= __ieee80211_start_scan(sdata
, req
);
757 /* need to complete scan in cfg80211 */
758 local
->scan_req
= req
;
766 * Avoid re-scheduling when the sdata is going away.
768 if (!ieee80211_sdata_running(sdata
)) {
774 * as long as no delay is required advance immediately
775 * without scheduling a new work
778 if (!ieee80211_sdata_running(sdata
)) {
783 switch (local
->next_scan_state
) {
785 /* if no more bands/channels left, complete scan */
786 if (local
->scan_channel_idx
>= local
->scan_req
->n_channels
) {
790 ieee80211_scan_state_decision(local
, &next_delay
);
792 case SCAN_SET_CHANNEL
:
793 ieee80211_scan_state_set_channel(local
, &next_delay
);
795 case SCAN_SEND_PROBE
:
796 ieee80211_scan_state_send_probe(local
, &next_delay
);
799 ieee80211_scan_state_suspend(local
, &next_delay
);
802 ieee80211_scan_state_resume(local
, &next_delay
);
808 } while (next_delay
== 0);
810 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, next_delay
);
814 hw_scan
= test_bit(SCAN_HW_SCANNING
, &local
->scanning
);
815 __ieee80211_scan_completed(&local
->hw
, aborted
, hw_scan
);
817 mutex_unlock(&local
->mtx
);
820 int ieee80211_request_scan(struct ieee80211_sub_if_data
*sdata
,
821 struct cfg80211_scan_request
*req
)
825 mutex_lock(&sdata
->local
->mtx
);
826 res
= __ieee80211_start_scan(sdata
, req
);
827 mutex_unlock(&sdata
->local
->mtx
);
832 int ieee80211_request_internal_scan(struct ieee80211_sub_if_data
*sdata
,
833 const u8
*ssid
, u8 ssid_len
,
834 struct ieee80211_channel
*chan
)
836 struct ieee80211_local
*local
= sdata
->local
;
838 enum ieee80211_band band
;
840 mutex_lock(&local
->mtx
);
846 /* fill internal scan request */
850 for (band
= 0; band
< IEEE80211_NUM_BANDS
; band
++) {
851 if (!local
->hw
.wiphy
->bands
[band
])
854 i
< local
->hw
.wiphy
->bands
[band
]->n_channels
;
856 local
->int_scan_req
->channels
[nchan
] =
857 &local
->hw
.wiphy
->bands
[band
]->channels
[i
];
862 local
->int_scan_req
->n_channels
= nchan
;
864 local
->int_scan_req
->channels
[0] = chan
;
865 local
->int_scan_req
->n_channels
= 1;
868 local
->int_scan_req
->ssids
= &local
->scan_ssid
;
869 local
->int_scan_req
->n_ssids
= 1;
870 memcpy(local
->int_scan_req
->ssids
[0].ssid
, ssid
, IEEE80211_MAX_SSID_LEN
);
871 local
->int_scan_req
->ssids
[0].ssid_len
= ssid_len
;
873 ret
= __ieee80211_start_scan(sdata
, sdata
->local
->int_scan_req
);
875 mutex_unlock(&local
->mtx
);
880 * Only call this function when a scan can't be queued -- under RTNL.
882 void ieee80211_scan_cancel(struct ieee80211_local
*local
)
885 * We are canceling software scan, or deferred scan that was not
886 * yet really started (see __ieee80211_start_scan ).
888 * Regarding hardware scan:
889 * - we can not call __ieee80211_scan_completed() as when
890 * SCAN_HW_SCANNING bit is set this function change
891 * local->hw_scan_req to operate on 5G band, what race with
892 * driver which can use local->hw_scan_req
894 * - we can not cancel scan_work since driver can schedule it
895 * by ieee80211_scan_completed(..., true) to finish scan
897 * Hence we only call the cancel_hw_scan() callback, but the low-level
898 * driver is still responsible for calling ieee80211_scan_completed()
899 * after the scan was completed/aborted.
902 mutex_lock(&local
->mtx
);
903 if (!local
->scan_req
)
906 if (test_bit(SCAN_HW_SCANNING
, &local
->scanning
)) {
907 if (local
->ops
->cancel_hw_scan
)
908 drv_cancel_hw_scan(local
,
909 rcu_dereference_protected(local
->scan_sdata
,
910 lockdep_is_held(&local
->mtx
)));
915 * If the work is currently running, it must be blocked on
916 * the mutex, but we'll set scan_sdata = NULL and it'll
917 * simply exit once it acquires the mutex.
919 cancel_delayed_work(&local
->scan_work
);
921 __ieee80211_scan_completed(&local
->hw
, true, false);
923 mutex_unlock(&local
->mtx
);
926 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data
*sdata
,
927 struct cfg80211_sched_scan_request
*req
)
929 struct ieee80211_local
*local
= sdata
->local
;
930 struct ieee80211_sched_scan_ies sched_scan_ies
= {};
933 mutex_lock(&local
->mtx
);
935 if (rcu_access_pointer(local
->sched_scan_sdata
)) {
940 if (!local
->ops
->sched_scan_start
) {
945 for (i
= 0; i
< IEEE80211_NUM_BANDS
; i
++) {
946 if (!local
->hw
.wiphy
->bands
[i
])
949 sched_scan_ies
.ie
[i
] = kzalloc(2 + IEEE80211_MAX_SSID_LEN
+
950 local
->scan_ies_len
+
953 if (!sched_scan_ies
.ie
[i
]) {
958 sched_scan_ies
.len
[i
] =
959 ieee80211_build_preq_ies(local
, sched_scan_ies
.ie
[i
],
960 req
->ie
, req
->ie_len
, i
,
964 ret
= drv_sched_scan_start(local
, sdata
, req
, &sched_scan_ies
);
966 rcu_assign_pointer(local
->sched_scan_sdata
, sdata
);
970 kfree(sched_scan_ies
.ie
[--i
]);
972 mutex_unlock(&local
->mtx
);
976 int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data
*sdata
)
978 struct ieee80211_local
*local
= sdata
->local
;
981 mutex_lock(&local
->mtx
);
983 if (!local
->ops
->sched_scan_stop
) {
988 if (rcu_access_pointer(local
->sched_scan_sdata
))
989 drv_sched_scan_stop(local
, sdata
);
992 mutex_unlock(&local
->mtx
);
997 void ieee80211_sched_scan_results(struct ieee80211_hw
*hw
)
999 struct ieee80211_local
*local
= hw_to_local(hw
);
1001 trace_api_sched_scan_results(local
);
1003 cfg80211_sched_scan_results(hw
->wiphy
);
1005 EXPORT_SYMBOL(ieee80211_sched_scan_results
);
1007 void ieee80211_sched_scan_stopped_work(struct work_struct
*work
)
1009 struct ieee80211_local
*local
=
1010 container_of(work
, struct ieee80211_local
,
1011 sched_scan_stopped_work
);
1013 mutex_lock(&local
->mtx
);
1015 if (!rcu_access_pointer(local
->sched_scan_sdata
)) {
1016 mutex_unlock(&local
->mtx
);
1020 rcu_assign_pointer(local
->sched_scan_sdata
, NULL
);
1022 mutex_unlock(&local
->mtx
);
1024 cfg80211_sched_scan_stopped(local
->hw
.wiphy
);
1027 void ieee80211_sched_scan_stopped(struct ieee80211_hw
*hw
)
1029 struct ieee80211_local
*local
= hw_to_local(hw
);
1031 trace_api_sched_scan_stopped(local
);
1033 ieee80211_queue_work(&local
->hw
, &local
->sched_scan_stopped_work
);
1035 EXPORT_SYMBOL(ieee80211_sched_scan_stopped
);