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/wireless.h>
16 #include <linux/if_arp.h>
17 #include <linux/rtnetlink.h>
18 #include <net/mac80211.h>
20 #include "ieee80211_i.h"
21 #include "driver-ops.h"
24 #define IEEE80211_PROBE_DELAY (HZ / 33)
25 #define IEEE80211_CHANNEL_TIME (HZ / 33)
26 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8)
28 struct ieee80211_bss
*
29 ieee80211_rx_bss_get(struct ieee80211_local
*local
, u8
*bssid
, int freq
,
30 u8
*ssid
, u8 ssid_len
)
32 return (void *)cfg80211_get_bss(local
->hw
.wiphy
,
33 ieee80211_get_channel(local
->hw
.wiphy
,
35 bssid
, ssid
, ssid_len
,
39 static void ieee80211_rx_bss_free(struct cfg80211_bss
*cbss
)
41 struct ieee80211_bss
*bss
= (void *)cbss
;
43 kfree(bss_mesh_id(bss
));
44 kfree(bss_mesh_cfg(bss
));
47 void ieee80211_rx_bss_put(struct ieee80211_local
*local
,
48 struct ieee80211_bss
*bss
)
50 cfg80211_put_bss((struct cfg80211_bss
*)bss
);
53 struct ieee80211_bss
*
54 ieee80211_bss_info_update(struct ieee80211_local
*local
,
55 struct ieee80211_rx_status
*rx_status
,
56 struct ieee80211_mgmt
*mgmt
,
58 struct ieee802_11_elems
*elems
,
59 struct ieee80211_channel
*channel
,
62 struct ieee80211_bss
*bss
;
66 if (local
->hw
.flags
& IEEE80211_HW_SIGNAL_DBM
)
67 signal
= rx_status
->signal
* 100;
68 else if (local
->hw
.flags
& IEEE80211_HW_SIGNAL_UNSPEC
)
69 signal
= (rx_status
->signal
* 100) / local
->hw
.max_signal
;
71 bss
= (void *)cfg80211_inform_bss_frame(local
->hw
.wiphy
, channel
,
72 mgmt
, len
, signal
, GFP_ATOMIC
);
77 bss
->cbss
.free_priv
= ieee80211_rx_bss_free
;
79 /* save the ERP value so that it is available at association time */
80 if (elems
->erp_info
&& elems
->erp_info_len
>= 1) {
81 bss
->erp_value
= elems
->erp_info
[0];
82 bss
->has_erp_value
= 1;
86 struct ieee80211_tim_ie
*tim_ie
=
87 (struct ieee80211_tim_ie
*)elems
->tim
;
88 bss
->dtim_period
= tim_ie
->dtim_period
;
91 /* set default value for buggy AP/no TIM element */
92 if (bss
->dtim_period
== 0)
95 bss
->supp_rates_len
= 0;
96 if (elems
->supp_rates
) {
97 clen
= IEEE80211_MAX_SUPP_RATES
- bss
->supp_rates_len
;
98 if (clen
> elems
->supp_rates_len
)
99 clen
= elems
->supp_rates_len
;
100 memcpy(&bss
->supp_rates
[bss
->supp_rates_len
], elems
->supp_rates
,
102 bss
->supp_rates_len
+= clen
;
104 if (elems
->ext_supp_rates
) {
105 clen
= IEEE80211_MAX_SUPP_RATES
- bss
->supp_rates_len
;
106 if (clen
> elems
->ext_supp_rates_len
)
107 clen
= elems
->ext_supp_rates_len
;
108 memcpy(&bss
->supp_rates
[bss
->supp_rates_len
],
109 elems
->ext_supp_rates
, clen
);
110 bss
->supp_rates_len
+= clen
;
113 bss
->wmm_used
= elems
->wmm_param
|| elems
->wmm_info
;
116 bss
->last_probe_resp
= jiffies
;
122 ieee80211_scan_rx(struct ieee80211_sub_if_data
*sdata
, struct sk_buff
*skb
)
124 struct ieee80211_rx_status
*rx_status
= IEEE80211_SKB_RXCB(skb
);
125 struct ieee80211_mgmt
*mgmt
;
126 struct ieee80211_bss
*bss
;
128 struct ieee80211_channel
*channel
;
132 bool presp
, beacon
= false;
133 struct ieee802_11_elems elems
;
136 return RX_DROP_UNUSABLE
;
138 mgmt
= (struct ieee80211_mgmt
*) skb
->data
;
139 fc
= mgmt
->frame_control
;
141 if (ieee80211_is_ctl(fc
))
145 return RX_DROP_MONITOR
;
147 presp
= ieee80211_is_probe_resp(fc
);
149 /* ignore ProbeResp to foreign address */
150 if (memcmp(mgmt
->da
, sdata
->vif
.addr
, ETH_ALEN
))
151 return RX_DROP_MONITOR
;
154 elements
= mgmt
->u
.probe_resp
.variable
;
155 baselen
= offsetof(struct ieee80211_mgmt
, u
.probe_resp
.variable
);
157 beacon
= ieee80211_is_beacon(fc
);
158 baselen
= offsetof(struct ieee80211_mgmt
, u
.beacon
.variable
);
159 elements
= mgmt
->u
.beacon
.variable
;
162 if (!presp
&& !beacon
)
165 if (baselen
> skb
->len
)
166 return RX_DROP_MONITOR
;
168 ieee802_11_parse_elems(elements
, skb
->len
- baselen
, &elems
);
170 if (elems
.ds_params
&& elems
.ds_params_len
== 1)
171 freq
= ieee80211_channel_to_frequency(elems
.ds_params
[0]);
173 freq
= rx_status
->freq
;
175 channel
= ieee80211_get_channel(sdata
->local
->hw
.wiphy
, freq
);
177 if (!channel
|| channel
->flags
& IEEE80211_CHAN_DISABLED
)
178 return RX_DROP_MONITOR
;
180 bss
= ieee80211_bss_info_update(sdata
->local
, rx_status
,
181 mgmt
, skb
->len
, &elems
,
184 ieee80211_rx_bss_put(sdata
->local
, bss
);
190 /* return false if no more work */
191 static bool ieee80211_prep_hw_scan(struct ieee80211_local
*local
)
193 struct cfg80211_scan_request
*req
= local
->scan_req
;
194 enum ieee80211_band band
;
195 int i
, ielen
, n_chans
;
198 if (local
->hw_scan_band
== IEEE80211_NUM_BANDS
)
201 band
= local
->hw_scan_band
;
203 for (i
= 0; i
< req
->n_channels
; i
++) {
204 if (req
->channels
[i
]->band
== band
) {
205 local
->hw_scan_req
->channels
[n_chans
] =
211 local
->hw_scan_band
++;
214 local
->hw_scan_req
->n_channels
= n_chans
;
216 ielen
= ieee80211_build_preq_ies(local
, (u8
*)local
->hw_scan_req
->ie
,
217 req
->ie
, req
->ie_len
, band
);
218 local
->hw_scan_req
->ie_len
= ielen
;
224 * inform AP that we will go to sleep so that it will buffer the frames
227 static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data
*sdata
)
229 struct ieee80211_local
*local
= sdata
->local
;
231 local
->scan_ps_enabled
= false;
233 /* FIXME: what to do when local->pspolling is true? */
235 del_timer_sync(&local
->dynamic_ps_timer
);
236 cancel_work_sync(&local
->dynamic_ps_enable_work
);
238 if (local
->hw
.conf
.flags
& IEEE80211_CONF_PS
) {
239 local
->scan_ps_enabled
= true;
240 local
->hw
.conf
.flags
&= ~IEEE80211_CONF_PS
;
241 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_PS
);
244 if (!(local
->scan_ps_enabled
) ||
245 !(local
->hw
.flags
& IEEE80211_HW_PS_NULLFUNC_STACK
))
247 * If power save was enabled, no need to send a nullfunc
248 * frame because AP knows that we are sleeping. But if the
249 * hardware is creating the nullfunc frame for power save
250 * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
251 * enabled) and power save was enabled, the firmware just
252 * sent a null frame with power save disabled. So we need
253 * to send a new nullfunc frame to inform the AP that we
254 * are again sleeping.
256 ieee80211_send_nullfunc(local
, sdata
, 1);
259 /* inform AP that we are awake again, unless power save is enabled */
260 static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data
*sdata
)
262 struct ieee80211_local
*local
= sdata
->local
;
264 if (!local
->ps_sdata
)
265 ieee80211_send_nullfunc(local
, sdata
, 0);
266 else if (local
->scan_ps_enabled
) {
268 * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware
269 * will send a nullfunc frame with the powersave bit set
270 * even though the AP already knows that we are sleeping.
271 * This could be avoided by sending a null frame with power
272 * save bit disabled before enabling the power save, but
273 * this doesn't gain anything.
275 * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need
276 * to send a nullfunc frame because AP already knows that
277 * we are sleeping, let's just enable power save mode in
280 local
->hw
.conf
.flags
|= IEEE80211_CONF_PS
;
281 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_PS
);
282 } else if (local
->hw
.conf
.dynamic_ps_timeout
> 0) {
284 * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer
285 * had been running before leaving the operating channel,
286 * restart the timer now and send a nullfunc frame to inform
287 * the AP that we are awake.
289 ieee80211_send_nullfunc(local
, sdata
, 0);
290 mod_timer(&local
->dynamic_ps_timer
, jiffies
+
291 msecs_to_jiffies(local
->hw
.conf
.dynamic_ps_timeout
));
295 void ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
)
297 struct ieee80211_local
*local
= hw_to_local(hw
);
298 struct ieee80211_sub_if_data
*sdata
;
301 mutex_lock(&local
->scan_mtx
);
304 * It's ok to abort a not-yet-running scan (that
305 * we have one at all will be verified by checking
306 * local->scan_req next), but not to complete it
309 if (WARN_ON(!local
->scanning
&& !aborted
))
312 if (WARN_ON(!local
->scan_req
)) {
313 mutex_unlock(&local
->scan_mtx
);
317 was_hw_scan
= test_bit(SCAN_HW_SCANNING
, &local
->scanning
);
318 if (was_hw_scan
&& !aborted
&& ieee80211_prep_hw_scan(local
)) {
319 ieee80211_queue_delayed_work(&local
->hw
,
320 &local
->scan_work
, 0);
321 mutex_unlock(&local
->scan_mtx
);
325 kfree(local
->hw_scan_req
);
326 local
->hw_scan_req
= NULL
;
328 if (local
->scan_req
!= local
->int_scan_req
)
329 cfg80211_scan_done(local
->scan_req
, aborted
);
330 local
->scan_req
= NULL
;
331 local
->scan_sdata
= NULL
;
334 local
->scan_channel
= NULL
;
336 /* we only have to protect scan_req and hw/sw scan */
337 mutex_unlock(&local
->scan_mtx
);
339 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
343 ieee80211_configure_filter(local
);
345 drv_sw_scan_complete(local
);
347 mutex_lock(&local
->iflist_mtx
);
348 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
349 if (!ieee80211_sdata_running(sdata
))
352 /* Tell AP we're back */
353 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
354 if (sdata
->u
.mgd
.associated
) {
355 ieee80211_scan_ps_disable(sdata
);
356 netif_wake_queue(sdata
->dev
);
359 netif_wake_queue(sdata
->dev
);
361 /* re-enable beaconing */
362 if (sdata
->vif
.type
== NL80211_IFTYPE_AP
||
363 sdata
->vif
.type
== NL80211_IFTYPE_ADHOC
||
364 sdata
->vif
.type
== NL80211_IFTYPE_MESH_POINT
)
365 ieee80211_bss_info_change_notify(
366 sdata
, BSS_CHANGED_BEACON_ENABLED
);
368 mutex_unlock(&local
->iflist_mtx
);
371 ieee80211_recalc_idle(local
);
372 ieee80211_mlme_notify_scan_completed(local
);
373 ieee80211_ibss_notify_scan_completed(local
);
374 ieee80211_mesh_notify_scan_completed(local
);
376 EXPORT_SYMBOL(ieee80211_scan_completed
);
378 static int ieee80211_start_sw_scan(struct ieee80211_local
*local
)
380 struct ieee80211_sub_if_data
*sdata
;
383 * Hardware/driver doesn't support hw_scan, so use software
384 * scanning instead. First send a nullfunc frame with power save
385 * bit on so that AP will buffer the frames for us while we are not
386 * listening, then send probe requests to each channel and wait for
387 * the responses. After all channels are scanned, tune back to the
388 * original channel and send a nullfunc frame with power save bit
389 * off to trigger the AP to send us all the buffered frames.
391 * Note that while local->sw_scanning is true everything else but
392 * nullfunc frames and probe requests will be dropped in
393 * ieee80211_tx_h_check_assoc().
395 drv_sw_scan_start(local
);
397 mutex_lock(&local
->iflist_mtx
);
398 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
399 if (!ieee80211_sdata_running(sdata
))
402 /* disable beaconing */
403 if (sdata
->vif
.type
== NL80211_IFTYPE_AP
||
404 sdata
->vif
.type
== NL80211_IFTYPE_ADHOC
||
405 sdata
->vif
.type
== NL80211_IFTYPE_MESH_POINT
)
406 ieee80211_bss_info_change_notify(
407 sdata
, BSS_CHANGED_BEACON_ENABLED
);
410 * only handle non-STA interfaces here, STA interfaces
411 * are handled in the scan state machine
413 if (sdata
->vif
.type
!= NL80211_IFTYPE_STATION
)
414 netif_stop_queue(sdata
->dev
);
416 mutex_unlock(&local
->iflist_mtx
);
418 local
->next_scan_state
= SCAN_DECISION
;
419 local
->scan_channel_idx
= 0;
421 drv_flush(local
, false);
423 ieee80211_configure_filter(local
);
425 ieee80211_queue_delayed_work(&local
->hw
,
427 IEEE80211_CHANNEL_TIME
);
433 static int __ieee80211_start_scan(struct ieee80211_sub_if_data
*sdata
,
434 struct cfg80211_scan_request
*req
)
436 struct ieee80211_local
*local
= sdata
->local
;
437 struct ieee80211_if_managed
*ifmgd
= &sdata
->u
.mgd
;
443 if (local
->ops
->hw_scan
) {
446 local
->hw_scan_req
= kmalloc(
447 sizeof(*local
->hw_scan_req
) +
448 req
->n_channels
* sizeof(req
->channels
[0]) +
449 2 + IEEE80211_MAX_SSID_LEN
+ local
->scan_ies_len
+
450 req
->ie_len
, GFP_KERNEL
);
451 if (!local
->hw_scan_req
)
454 local
->hw_scan_req
->ssids
= req
->ssids
;
455 local
->hw_scan_req
->n_ssids
= req
->n_ssids
;
456 ies
= (u8
*)local
->hw_scan_req
+
457 sizeof(*local
->hw_scan_req
) +
458 req
->n_channels
* sizeof(req
->channels
[0]);
459 local
->hw_scan_req
->ie
= ies
;
461 local
->hw_scan_band
= 0;
464 local
->scan_req
= req
;
465 local
->scan_sdata
= sdata
;
467 if (req
!= local
->int_scan_req
&&
468 sdata
->vif
.type
== NL80211_IFTYPE_STATION
&&
469 !list_empty(&ifmgd
->work_list
)) {
470 /* actually wait for the work it's doing to finish/time out */
471 set_bit(IEEE80211_STA_REQ_SCAN
, &ifmgd
->request
);
475 if (local
->ops
->hw_scan
)
476 __set_bit(SCAN_HW_SCANNING
, &local
->scanning
);
478 __set_bit(SCAN_SW_SCANNING
, &local
->scanning
);
480 * Kicking off the scan need not be protected,
481 * only the scan variable stuff, since now
482 * local->scan_req is assigned and other callers
483 * will abort their scan attempts.
485 * This avoids getting a scan_mtx -> iflist_mtx
486 * dependency, so that the scan completed calls
487 * have more locking freedom.
490 ieee80211_recalc_idle(local
);
491 mutex_unlock(&local
->scan_mtx
);
493 if (local
->ops
->hw_scan
) {
494 WARN_ON(!ieee80211_prep_hw_scan(local
));
495 rc
= drv_hw_scan(local
, local
->hw_scan_req
);
497 rc
= ieee80211_start_sw_scan(local
);
499 mutex_lock(&local
->scan_mtx
);
502 kfree(local
->hw_scan_req
);
503 local
->hw_scan_req
= NULL
;
506 ieee80211_recalc_idle(local
);
508 local
->scan_req
= NULL
;
509 local
->scan_sdata
= NULL
;
515 static int ieee80211_scan_state_decision(struct ieee80211_local
*local
,
516 unsigned long *next_delay
)
518 bool associated
= false;
519 struct ieee80211_sub_if_data
*sdata
;
521 /* if no more bands/channels left, complete scan and advance to the idle state */
522 if (local
->scan_channel_idx
>= local
->scan_req
->n_channels
) {
523 ieee80211_scan_completed(&local
->hw
, false);
527 /* check if at least one STA interface is associated */
528 mutex_lock(&local
->iflist_mtx
);
529 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
530 if (!ieee80211_sdata_running(sdata
))
533 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
534 if (sdata
->u
.mgd
.associated
) {
540 mutex_unlock(&local
->iflist_mtx
);
542 if (local
->scan_channel
) {
544 * we're currently scanning a different channel, let's
545 * switch back to the operating channel now if at least
546 * one interface is associated. Otherwise just scan the
550 local
->next_scan_state
= SCAN_ENTER_OPER_CHANNEL
;
552 local
->next_scan_state
= SCAN_SET_CHANNEL
;
555 * we're on the operating channel currently, let's
556 * leave that channel now to scan another one
558 local
->next_scan_state
= SCAN_LEAVE_OPER_CHANNEL
;
565 static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local
*local
,
566 unsigned long *next_delay
)
568 struct ieee80211_sub_if_data
*sdata
;
571 * notify the AP about us leaving the channel and stop all STA interfaces
573 mutex_lock(&local
->iflist_mtx
);
574 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
575 if (!ieee80211_sdata_running(sdata
))
578 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
579 netif_stop_queue(sdata
->dev
);
580 if (sdata
->u
.mgd
.associated
)
581 ieee80211_scan_ps_enable(sdata
);
584 mutex_unlock(&local
->iflist_mtx
);
586 __set_bit(SCAN_OFF_CHANNEL
, &local
->scanning
);
589 * What if the nullfunc frames didn't arrive?
591 drv_flush(local
, false);
592 if (local
->ops
->flush
)
595 *next_delay
= HZ
/ 10;
597 /* advance to the next channel to be scanned */
598 local
->next_scan_state
= SCAN_SET_CHANNEL
;
601 static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local
*local
,
602 unsigned long *next_delay
)
604 struct ieee80211_sub_if_data
*sdata
= local
->scan_sdata
;
606 /* switch back to the operating channel */
607 local
->scan_channel
= NULL
;
608 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
611 * notify the AP about us being back and restart all STA interfaces
613 mutex_lock(&local
->iflist_mtx
);
614 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
615 if (!ieee80211_sdata_running(sdata
))
618 /* Tell AP we're back */
619 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
620 if (sdata
->u
.mgd
.associated
)
621 ieee80211_scan_ps_disable(sdata
);
622 netif_wake_queue(sdata
->dev
);
625 mutex_unlock(&local
->iflist_mtx
);
627 __clear_bit(SCAN_OFF_CHANNEL
, &local
->scanning
);
629 *next_delay
= HZ
/ 5;
630 local
->next_scan_state
= SCAN_DECISION
;
633 static void ieee80211_scan_state_set_channel(struct ieee80211_local
*local
,
634 unsigned long *next_delay
)
637 struct ieee80211_channel
*chan
;
640 chan
= local
->scan_req
->channels
[local
->scan_channel_idx
];
642 local
->scan_channel
= chan
;
643 if (ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
))
646 /* advance state machine to next channel/band */
647 local
->scan_channel_idx
++;
650 /* if we skip this channel return to the decision state */
651 local
->next_scan_state
= SCAN_DECISION
;
656 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
657 * (which unfortunately doesn't say _why_ step a) is done,
658 * but it waits for the probe delay or until a frame is
659 * received - and the received frame would update the NAV).
660 * For now, we do not support waiting until a frame is
663 * In any case, it is not necessary for a passive scan.
665 if (chan
->flags
& IEEE80211_CHAN_PASSIVE_SCAN
||
666 !local
->scan_req
->n_ssids
) {
667 *next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
668 local
->next_scan_state
= SCAN_DECISION
;
672 /* active scan, send probes */
673 *next_delay
= IEEE80211_PROBE_DELAY
;
674 local
->next_scan_state
= SCAN_SEND_PROBE
;
677 static void ieee80211_scan_state_send_probe(struct ieee80211_local
*local
,
678 unsigned long *next_delay
)
681 struct ieee80211_sub_if_data
*sdata
= local
->scan_sdata
;
683 for (i
= 0; i
< local
->scan_req
->n_ssids
; i
++)
684 ieee80211_send_probe_req(
686 local
->scan_req
->ssids
[i
].ssid
,
687 local
->scan_req
->ssids
[i
].ssid_len
,
688 local
->scan_req
->ie
, local
->scan_req
->ie_len
);
691 * After sending probe requests, wait for probe responses
694 *next_delay
= IEEE80211_CHANNEL_TIME
;
695 local
->next_scan_state
= SCAN_DECISION
;
698 void ieee80211_scan_work(struct work_struct
*work
)
700 struct ieee80211_local
*local
=
701 container_of(work
, struct ieee80211_local
, scan_work
.work
);
702 struct ieee80211_sub_if_data
*sdata
= local
->scan_sdata
;
703 unsigned long next_delay
= 0;
705 mutex_lock(&local
->scan_mtx
);
706 if (!sdata
|| !local
->scan_req
) {
707 mutex_unlock(&local
->scan_mtx
);
711 if (local
->hw_scan_req
) {
712 int rc
= drv_hw_scan(local
, local
->hw_scan_req
);
713 mutex_unlock(&local
->scan_mtx
);
715 ieee80211_scan_completed(&local
->hw
, true);
719 if (local
->scan_req
&& !local
->scanning
) {
720 struct cfg80211_scan_request
*req
= local
->scan_req
;
723 local
->scan_req
= NULL
;
724 local
->scan_sdata
= NULL
;
726 rc
= __ieee80211_start_scan(sdata
, req
);
727 mutex_unlock(&local
->scan_mtx
);
730 ieee80211_scan_completed(&local
->hw
, true);
734 mutex_unlock(&local
->scan_mtx
);
737 * Avoid re-scheduling when the sdata is going away.
739 if (!ieee80211_sdata_running(sdata
)) {
740 ieee80211_scan_completed(&local
->hw
, true);
745 * as long as no delay is required advance immediately
746 * without scheduling a new work
749 switch (local
->next_scan_state
) {
751 if (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
);
760 case SCAN_LEAVE_OPER_CHANNEL
:
761 ieee80211_scan_state_leave_oper_channel(local
, &next_delay
);
763 case SCAN_ENTER_OPER_CHANNEL
:
764 ieee80211_scan_state_enter_oper_channel(local
, &next_delay
);
767 } while (next_delay
== 0);
769 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, next_delay
);
772 int ieee80211_request_scan(struct ieee80211_sub_if_data
*sdata
,
773 struct cfg80211_scan_request
*req
)
777 mutex_lock(&sdata
->local
->scan_mtx
);
778 res
= __ieee80211_start_scan(sdata
, req
);
779 mutex_unlock(&sdata
->local
->scan_mtx
);
784 int ieee80211_request_internal_scan(struct ieee80211_sub_if_data
*sdata
,
785 const u8
*ssid
, u8 ssid_len
)
787 struct ieee80211_local
*local
= sdata
->local
;
790 mutex_lock(&local
->scan_mtx
);
796 memcpy(local
->int_scan_req
->ssids
[0].ssid
, ssid
, IEEE80211_MAX_SSID_LEN
);
797 local
->int_scan_req
->ssids
[0].ssid_len
= ssid_len
;
799 ret
= __ieee80211_start_scan(sdata
, sdata
->local
->int_scan_req
);
801 mutex_unlock(&local
->scan_mtx
);
805 void ieee80211_scan_cancel(struct ieee80211_local
*local
)
809 cancel_delayed_work_sync(&local
->scan_work
);
812 * Only call this function when a scan can't be
813 * queued -- mostly at suspend under RTNL.
815 mutex_lock(&local
->scan_mtx
);
816 abortscan
= test_bit(SCAN_SW_SCANNING
, &local
->scanning
) ||
817 (!local
->scanning
&& local
->scan_req
);
818 mutex_unlock(&local
->scan_mtx
);
821 ieee80211_scan_completed(&local
->hw
, true);