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
)) {
296 int rc
= drv_hw_scan(local
, local
->scan_sdata
, local
->hw_scan_req
);
301 kfree(local
->hw_scan_req
);
302 local
->hw_scan_req
= NULL
;
304 if (local
->scan_req
!= local
->int_scan_req
)
305 cfg80211_scan_done(local
->scan_req
, aborted
);
306 local
->scan_req
= NULL
;
307 local
->scan_sdata
= NULL
;
310 local
->scan_channel
= NULL
;
312 /* Set power back to normal operating levels. */
313 ieee80211_hw_config(local
, 0);
316 ieee80211_configure_filter(local
);
317 drv_sw_scan_complete(local
);
318 ieee80211_offchannel_return(local
, true);
321 ieee80211_recalc_idle(local
);
323 ieee80211_mlme_notify_scan_completed(local
);
324 ieee80211_ibss_notify_scan_completed(local
);
325 ieee80211_mesh_notify_scan_completed(local
);
326 ieee80211_queue_work(&local
->hw
, &local
->work_work
);
329 void ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
)
331 struct ieee80211_local
*local
= hw_to_local(hw
);
333 trace_api_scan_completed(local
, aborted
);
335 set_bit(SCAN_COMPLETED
, &local
->scanning
);
337 set_bit(SCAN_ABORTED
, &local
->scanning
);
338 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, 0);
340 EXPORT_SYMBOL(ieee80211_scan_completed
);
342 static int ieee80211_start_sw_scan(struct ieee80211_local
*local
)
345 * Hardware/driver doesn't support hw_scan, so use software
346 * scanning instead. First send a nullfunc frame with power save
347 * bit on so that AP will buffer the frames for us while we are not
348 * listening, then send probe requests to each channel and wait for
349 * the responses. After all channels are scanned, tune back to the
350 * original channel and send a nullfunc frame with power save bit
351 * off to trigger the AP to send us all the buffered frames.
353 * Note that while local->sw_scanning is true everything else but
354 * nullfunc frames and probe requests will be dropped in
355 * ieee80211_tx_h_check_assoc().
357 drv_sw_scan_start(local
);
359 local
->leave_oper_channel_time
= jiffies
;
360 local
->next_scan_state
= SCAN_DECISION
;
361 local
->scan_channel_idx
= 0;
363 ieee80211_offchannel_stop_vifs(local
, true);
365 ieee80211_configure_filter(local
);
367 /* We need to set power level at maximum rate for scanning. */
368 ieee80211_hw_config(local
, 0);
370 ieee80211_queue_delayed_work(&local
->hw
,
371 &local
->scan_work
, 0);
376 static bool ieee80211_can_scan(struct ieee80211_local
*local
,
377 struct ieee80211_sub_if_data
*sdata
)
379 if (!list_empty(&local
->work_list
))
382 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
&&
383 sdata
->u
.mgd
.flags
& (IEEE80211_STA_BEACON_POLL
|
384 IEEE80211_STA_CONNECTION_POLL
))
390 void ieee80211_run_deferred_scan(struct ieee80211_local
*local
)
392 lockdep_assert_held(&local
->mtx
);
394 if (!local
->scan_req
|| local
->scanning
)
397 if (!ieee80211_can_scan(local
, local
->scan_sdata
))
400 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
401 round_jiffies_relative(0));
404 static void ieee80211_scan_state_send_probe(struct ieee80211_local
*local
,
405 unsigned long *next_delay
)
408 struct ieee80211_sub_if_data
*sdata
= local
->scan_sdata
;
409 enum ieee80211_band band
= local
->hw
.conf
.channel
->band
;
411 for (i
= 0; i
< local
->scan_req
->n_ssids
; i
++)
412 ieee80211_send_probe_req(
414 local
->scan_req
->ssids
[i
].ssid
,
415 local
->scan_req
->ssids
[i
].ssid_len
,
416 local
->scan_req
->ie
, local
->scan_req
->ie_len
,
417 local
->scan_req
->rates
[band
], false,
418 local
->scan_req
->no_cck
);
421 * After sending probe requests, wait for probe responses
424 *next_delay
= IEEE80211_CHANNEL_TIME
;
425 local
->next_scan_state
= SCAN_DECISION
;
428 static int __ieee80211_start_scan(struct ieee80211_sub_if_data
*sdata
,
429 struct cfg80211_scan_request
*req
)
431 struct ieee80211_local
*local
= sdata
->local
;
434 lockdep_assert_held(&local
->mtx
);
439 if (!ieee80211_can_scan(local
, sdata
)) {
440 /* wait for the work to finish/time out */
441 local
->scan_req
= req
;
442 local
->scan_sdata
= sdata
;
446 if (local
->ops
->hw_scan
) {
449 local
->hw_scan_req
= kmalloc(
450 sizeof(*local
->hw_scan_req
) +
451 req
->n_channels
* sizeof(req
->channels
[0]) +
452 2 + IEEE80211_MAX_SSID_LEN
+ local
->scan_ies_len
+
453 req
->ie_len
, GFP_KERNEL
);
454 if (!local
->hw_scan_req
)
457 local
->hw_scan_req
->ssids
= req
->ssids
;
458 local
->hw_scan_req
->n_ssids
= req
->n_ssids
;
459 ies
= (u8
*)local
->hw_scan_req
+
460 sizeof(*local
->hw_scan_req
) +
461 req
->n_channels
* sizeof(req
->channels
[0]);
462 local
->hw_scan_req
->ie
= ies
;
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 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]->center_freq
==
482 local
->hw
.conf
.channel
->center_freq
)) {
484 /* If we are scanning only on the current channel, then
485 * we do not need to stop normal activities
487 unsigned long next_delay
;
489 __set_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
);
491 ieee80211_recalc_idle(local
);
493 /* Notify driver scan is starting, keep order of operations
494 * same as normal software scan, in case that matters. */
495 drv_sw_scan_start(local
);
497 ieee80211_configure_filter(local
); /* accept probe-responses */
499 /* We need to ensure power level is at max for scanning. */
500 ieee80211_hw_config(local
, 0);
502 if ((req
->channels
[0]->flags
&
503 IEEE80211_CHAN_PASSIVE_SCAN
) ||
504 !local
->scan_req
->n_ssids
) {
505 next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
507 ieee80211_scan_state_send_probe(local
, &next_delay
);
508 next_delay
= IEEE80211_CHANNEL_TIME
;
511 /* Now, just wait a bit and we are all done! */
512 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
516 /* Do normal software scan */
517 __set_bit(SCAN_SW_SCANNING
, &local
->scanning
);
520 ieee80211_recalc_idle(local
);
522 if (local
->ops
->hw_scan
) {
523 WARN_ON(!ieee80211_prep_hw_scan(local
));
524 rc
= drv_hw_scan(local
, sdata
, local
->hw_scan_req
);
526 rc
= ieee80211_start_sw_scan(local
);
529 kfree(local
->hw_scan_req
);
530 local
->hw_scan_req
= NULL
;
533 ieee80211_recalc_idle(local
);
535 local
->scan_req
= NULL
;
536 local
->scan_sdata
= NULL
;
543 ieee80211_scan_get_channel_time(struct ieee80211_channel
*chan
)
546 * TODO: channel switching also consumes quite some time,
547 * add that delay as well to get a better estimation
549 if (chan
->flags
& IEEE80211_CHAN_PASSIVE_SCAN
)
550 return IEEE80211_PASSIVE_CHANNEL_TIME
;
551 return IEEE80211_PROBE_DELAY
+ IEEE80211_CHANNEL_TIME
;
554 static void ieee80211_scan_state_decision(struct ieee80211_local
*local
,
555 unsigned long *next_delay
)
557 bool associated
= false;
558 bool tx_empty
= true;
560 bool listen_int_exceeded
;
561 unsigned long min_beacon_int
= 0;
562 struct ieee80211_sub_if_data
*sdata
;
563 struct ieee80211_channel
*next_chan
;
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
|| bad_latency
|| listen_int_exceeded
))
623 local
->next_scan_state
= SCAN_SUSPEND
;
625 local
->next_scan_state
= SCAN_SET_CHANNEL
;
630 static void ieee80211_scan_state_set_channel(struct ieee80211_local
*local
,
631 unsigned long *next_delay
)
634 struct ieee80211_channel
*chan
;
637 chan
= local
->scan_req
->channels
[local
->scan_channel_idx
];
639 local
->scan_channel
= chan
;
641 if (ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
))
644 /* advance state machine to next channel/band */
645 local
->scan_channel_idx
++;
648 /* if we skip this channel return to the decision state */
649 local
->next_scan_state
= SCAN_DECISION
;
654 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
655 * (which unfortunately doesn't say _why_ step a) is done,
656 * but it waits for the probe delay or until a frame is
657 * received - and the received frame would update the NAV).
658 * For now, we do not support waiting until a frame is
661 * In any case, it is not necessary for a passive scan.
663 if (chan
->flags
& IEEE80211_CHAN_PASSIVE_SCAN
||
664 !local
->scan_req
->n_ssids
) {
665 *next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
666 local
->next_scan_state
= SCAN_DECISION
;
670 /* active scan, send probes */
671 *next_delay
= IEEE80211_PROBE_DELAY
;
672 local
->next_scan_state
= SCAN_SEND_PROBE
;
675 static void ieee80211_scan_state_suspend(struct ieee80211_local
*local
,
676 unsigned long *next_delay
)
678 /* switch back to the operating channel */
679 local
->scan_channel
= NULL
;
680 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
683 * Re-enable vifs and beaconing. Leave PS
684 * in off-channel state..will put that back
685 * on-channel at the end of scanning.
687 ieee80211_offchannel_return(local
, false);
689 *next_delay
= HZ
/ 5;
690 /* afterwards, resume scan & go to next channel */
691 local
->next_scan_state
= SCAN_RESUME
;
694 static void ieee80211_scan_state_resume(struct ieee80211_local
*local
,
695 unsigned long *next_delay
)
697 /* PS already is in off-channel mode */
698 ieee80211_offchannel_stop_vifs(local
, false);
700 if (local
->ops
->flush
) {
701 drv_flush(local
, false);
704 *next_delay
= HZ
/ 10;
706 /* remember when we left the operating channel */
707 local
->leave_oper_channel_time
= jiffies
;
709 /* advance to the next channel to be scanned */
710 local
->next_scan_state
= SCAN_SET_CHANNEL
;
713 void ieee80211_scan_work(struct work_struct
*work
)
715 struct ieee80211_local
*local
=
716 container_of(work
, struct ieee80211_local
, scan_work
.work
);
717 struct ieee80211_sub_if_data
*sdata
;
718 unsigned long next_delay
= 0;
719 bool aborted
, hw_scan
;
721 mutex_lock(&local
->mtx
);
723 sdata
= local
->scan_sdata
;
725 /* When scanning on-channel, the first-callback means completed. */
726 if (test_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
)) {
727 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
731 if (test_and_clear_bit(SCAN_COMPLETED
, &local
->scanning
)) {
732 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
736 if (!sdata
|| !local
->scan_req
)
739 if (local
->scan_req
&& !local
->scanning
) {
740 struct cfg80211_scan_request
*req
= local
->scan_req
;
743 local
->scan_req
= NULL
;
744 local
->scan_sdata
= NULL
;
746 rc
= __ieee80211_start_scan(sdata
, req
);
748 /* need to complete scan in cfg80211 */
749 local
->scan_req
= req
;
757 * Avoid re-scheduling when the sdata is going away.
759 if (!ieee80211_sdata_running(sdata
)) {
765 * as long as no delay is required advance immediately
766 * without scheduling a new work
769 if (!ieee80211_sdata_running(sdata
)) {
774 switch (local
->next_scan_state
) {
776 /* if no more bands/channels left, complete scan */
777 if (local
->scan_channel_idx
>= local
->scan_req
->n_channels
) {
781 ieee80211_scan_state_decision(local
, &next_delay
);
783 case SCAN_SET_CHANNEL
:
784 ieee80211_scan_state_set_channel(local
, &next_delay
);
786 case SCAN_SEND_PROBE
:
787 ieee80211_scan_state_send_probe(local
, &next_delay
);
790 ieee80211_scan_state_suspend(local
, &next_delay
);
793 ieee80211_scan_state_resume(local
, &next_delay
);
796 } while (next_delay
== 0);
798 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, next_delay
);
802 hw_scan
= test_bit(SCAN_HW_SCANNING
, &local
->scanning
);
803 __ieee80211_scan_completed(&local
->hw
, aborted
, hw_scan
);
805 mutex_unlock(&local
->mtx
);
808 int ieee80211_request_scan(struct ieee80211_sub_if_data
*sdata
,
809 struct cfg80211_scan_request
*req
)
813 mutex_lock(&sdata
->local
->mtx
);
814 res
= __ieee80211_start_scan(sdata
, req
);
815 mutex_unlock(&sdata
->local
->mtx
);
820 int ieee80211_request_internal_scan(struct ieee80211_sub_if_data
*sdata
,
821 const u8
*ssid
, u8 ssid_len
,
822 struct ieee80211_channel
*chan
)
824 struct ieee80211_local
*local
= sdata
->local
;
826 enum ieee80211_band band
;
828 mutex_lock(&local
->mtx
);
834 /* fill internal scan request */
838 for (band
= 0; band
< IEEE80211_NUM_BANDS
; band
++) {
839 if (!local
->hw
.wiphy
->bands
[band
])
842 i
< local
->hw
.wiphy
->bands
[band
]->n_channels
;
844 local
->int_scan_req
->channels
[nchan
] =
845 &local
->hw
.wiphy
->bands
[band
]->channels
[i
];
850 local
->int_scan_req
->n_channels
= nchan
;
852 local
->int_scan_req
->channels
[0] = chan
;
853 local
->int_scan_req
->n_channels
= 1;
856 local
->int_scan_req
->ssids
= &local
->scan_ssid
;
857 local
->int_scan_req
->n_ssids
= 1;
858 memcpy(local
->int_scan_req
->ssids
[0].ssid
, ssid
, IEEE80211_MAX_SSID_LEN
);
859 local
->int_scan_req
->ssids
[0].ssid_len
= ssid_len
;
861 ret
= __ieee80211_start_scan(sdata
, sdata
->local
->int_scan_req
);
863 mutex_unlock(&local
->mtx
);
868 * Only call this function when a scan can't be queued -- under RTNL.
870 void ieee80211_scan_cancel(struct ieee80211_local
*local
)
873 * We are canceling software scan, or deferred scan that was not
874 * yet really started (see __ieee80211_start_scan ).
876 * Regarding hardware scan:
877 * - we can not call __ieee80211_scan_completed() as when
878 * SCAN_HW_SCANNING bit is set this function change
879 * local->hw_scan_req to operate on 5G band, what race with
880 * driver which can use local->hw_scan_req
882 * - we can not cancel scan_work since driver can schedule it
883 * by ieee80211_scan_completed(..., true) to finish scan
885 * Hence we only call the cancel_hw_scan() callback, but the low-level
886 * driver is still responsible for calling ieee80211_scan_completed()
887 * after the scan was completed/aborted.
890 mutex_lock(&local
->mtx
);
891 if (!local
->scan_req
)
894 if (test_bit(SCAN_HW_SCANNING
, &local
->scanning
)) {
895 if (local
->ops
->cancel_hw_scan
)
896 drv_cancel_hw_scan(local
, local
->scan_sdata
);
901 * If the work is currently running, it must be blocked on
902 * the mutex, but we'll set scan_sdata = NULL and it'll
903 * simply exit once it acquires the mutex.
905 cancel_delayed_work(&local
->scan_work
);
907 __ieee80211_scan_completed(&local
->hw
, true, false);
909 mutex_unlock(&local
->mtx
);
912 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data
*sdata
,
913 struct cfg80211_sched_scan_request
*req
)
915 struct ieee80211_local
*local
= sdata
->local
;
918 mutex_lock(&sdata
->local
->mtx
);
920 if (local
->sched_scanning
) {
925 if (!local
->ops
->sched_scan_start
) {
930 for (i
= 0; i
< IEEE80211_NUM_BANDS
; i
++) {
931 local
->sched_scan_ies
.ie
[i
] = kzalloc(2 +
932 IEEE80211_MAX_SSID_LEN
+
933 local
->scan_ies_len
+
936 if (!local
->sched_scan_ies
.ie
[i
]) {
941 local
->sched_scan_ies
.len
[i
] =
942 ieee80211_build_preq_ies(local
,
943 local
->sched_scan_ies
.ie
[i
],
944 req
->ie
, req
->ie_len
, i
,
948 ret
= drv_sched_scan_start(local
, sdata
, req
,
949 &local
->sched_scan_ies
);
951 local
->sched_scanning
= true;
957 kfree(local
->sched_scan_ies
.ie
[--i
]);
959 mutex_unlock(&sdata
->local
->mtx
);
963 int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data
*sdata
)
965 struct ieee80211_local
*local
= sdata
->local
;
968 mutex_lock(&sdata
->local
->mtx
);
970 if (!local
->ops
->sched_scan_stop
) {
975 if (local
->sched_scanning
) {
976 for (i
= 0; i
< IEEE80211_NUM_BANDS
; i
++)
977 kfree(local
->sched_scan_ies
.ie
[i
]);
979 drv_sched_scan_stop(local
, sdata
);
980 local
->sched_scanning
= false;
983 mutex_unlock(&sdata
->local
->mtx
);
988 void ieee80211_sched_scan_results(struct ieee80211_hw
*hw
)
990 struct ieee80211_local
*local
= hw_to_local(hw
);
992 trace_api_sched_scan_results(local
);
994 cfg80211_sched_scan_results(hw
->wiphy
);
996 EXPORT_SYMBOL(ieee80211_sched_scan_results
);
998 void ieee80211_sched_scan_stopped_work(struct work_struct
*work
)
1000 struct ieee80211_local
*local
=
1001 container_of(work
, struct ieee80211_local
,
1002 sched_scan_stopped_work
);
1005 mutex_lock(&local
->mtx
);
1007 if (!local
->sched_scanning
) {
1008 mutex_unlock(&local
->mtx
);
1012 for (i
= 0; i
< IEEE80211_NUM_BANDS
; i
++)
1013 kfree(local
->sched_scan_ies
.ie
[i
]);
1015 local
->sched_scanning
= false;
1017 mutex_unlock(&local
->mtx
);
1019 cfg80211_sched_scan_stopped(local
->hw
.wiphy
);
1022 void ieee80211_sched_scan_stopped(struct ieee80211_hw
*hw
)
1024 struct ieee80211_local
*local
= hw_to_local(hw
);
1026 trace_api_sched_scan_stopped(local
);
1028 ieee80211_queue_work(&local
->hw
, &local
->sched_scan_stopped_work
);
1030 EXPORT_SYMBOL(ieee80211_sched_scan_stopped
);