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>
9 * Copyright 2013-2015 Intel Mobile Communications GmbH
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
16 #include <linux/if_arp.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rtnetlink.h>
19 #include <net/sch_generic.h>
20 #include <linux/slab.h>
21 #include <linux/export.h>
22 #include <net/mac80211.h>
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
28 #define IEEE80211_PROBE_DELAY (HZ / 33)
29 #define IEEE80211_CHANNEL_TIME (HZ / 33)
30 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
32 void ieee80211_rx_bss_put(struct ieee80211_local
*local
,
33 struct ieee80211_bss
*bss
)
37 cfg80211_put_bss(local
->hw
.wiphy
,
38 container_of((void *)bss
, struct cfg80211_bss
, priv
));
41 static bool is_uapsd_supported(struct ieee802_11_elems
*elems
)
45 if (elems
->wmm_info
&& elems
->wmm_info_len
== 7
46 && elems
->wmm_info
[5] == 1)
47 qos_info
= elems
->wmm_info
[6];
48 else if (elems
->wmm_param
&& elems
->wmm_param_len
== 24
49 && elems
->wmm_param
[5] == 1)
50 qos_info
= elems
->wmm_param
[6];
52 /* no valid wmm information or parameter element found */
55 return qos_info
& IEEE80211_WMM_IE_AP_QOSINFO_UAPSD
;
58 struct ieee80211_bss
*
59 ieee80211_bss_info_update(struct ieee80211_local
*local
,
60 struct ieee80211_rx_status
*rx_status
,
61 struct ieee80211_mgmt
*mgmt
, size_t len
,
62 struct ieee802_11_elems
*elems
,
63 struct ieee80211_channel
*channel
)
65 bool beacon
= ieee80211_is_beacon(mgmt
->frame_control
);
66 struct cfg80211_bss
*cbss
;
67 struct ieee80211_bss
*bss
;
69 struct cfg80211_inform_bss bss_meta
= {
70 .boottime_ns
= rx_status
->boottime_ns
,
74 if (ieee80211_hw_check(&local
->hw
, SIGNAL_DBM
))
75 bss_meta
.signal
= rx_status
->signal
* 100;
76 else if (ieee80211_hw_check(&local
->hw
, SIGNAL_UNSPEC
))
77 bss_meta
.signal
= (rx_status
->signal
* 100) / local
->hw
.max_signal
;
79 bss_meta
.scan_width
= NL80211_BSS_CHAN_WIDTH_20
;
80 if (rx_status
->flag
& RX_FLAG_5MHZ
)
81 bss_meta
.scan_width
= NL80211_BSS_CHAN_WIDTH_5
;
82 if (rx_status
->flag
& RX_FLAG_10MHZ
)
83 bss_meta
.scan_width
= NL80211_BSS_CHAN_WIDTH_10
;
85 bss_meta
.chan
= channel
;
86 cbss
= cfg80211_inform_bss_frame_data(local
->hw
.wiphy
, &bss_meta
,
87 mgmt
, len
, GFP_ATOMIC
);
90 /* In case the signal is invalid update the status */
91 signal_valid
= abs(channel
->center_freq
- cbss
->channel
->center_freq
)
92 <= local
->hw
.wiphy
->max_adj_channel_rssi_comp
;
94 rx_status
->flag
|= RX_FLAG_NO_SIGNAL_VAL
;
96 bss
= (void *)cbss
->priv
;
99 bss
->device_ts_beacon
= rx_status
->device_timestamp
;
101 bss
->device_ts_presp
= rx_status
->device_timestamp
;
103 if (elems
->parse_error
) {
105 bss
->corrupt_data
|= IEEE80211_BSS_CORRUPT_BEACON
;
107 bss
->corrupt_data
|= IEEE80211_BSS_CORRUPT_PROBE_RESP
;
110 bss
->corrupt_data
&= ~IEEE80211_BSS_CORRUPT_BEACON
;
112 bss
->corrupt_data
&= ~IEEE80211_BSS_CORRUPT_PROBE_RESP
;
115 /* save the ERP value so that it is available at association time */
116 if (elems
->erp_info
&& (!elems
->parse_error
||
117 !(bss
->valid_data
& IEEE80211_BSS_VALID_ERP
))) {
118 bss
->erp_value
= elems
->erp_info
[0];
119 bss
->has_erp_value
= true;
120 if (!elems
->parse_error
)
121 bss
->valid_data
|= IEEE80211_BSS_VALID_ERP
;
124 /* replace old supported rates if we get new values */
125 if (!elems
->parse_error
||
126 !(bss
->valid_data
& IEEE80211_BSS_VALID_RATES
)) {
128 if (elems
->supp_rates
) {
129 clen
= IEEE80211_MAX_SUPP_RATES
;
130 if (clen
> elems
->supp_rates_len
)
131 clen
= elems
->supp_rates_len
;
132 memcpy(bss
->supp_rates
, elems
->supp_rates
, clen
);
135 if (elems
->ext_supp_rates
) {
136 clen
= IEEE80211_MAX_SUPP_RATES
- srlen
;
137 if (clen
> elems
->ext_supp_rates_len
)
138 clen
= elems
->ext_supp_rates_len
;
139 memcpy(bss
->supp_rates
+ srlen
, elems
->ext_supp_rates
,
144 bss
->supp_rates_len
= srlen
;
145 if (!elems
->parse_error
)
146 bss
->valid_data
|= IEEE80211_BSS_VALID_RATES
;
150 if (!elems
->parse_error
||
151 !(bss
->valid_data
& IEEE80211_BSS_VALID_WMM
)) {
152 bss
->wmm_used
= elems
->wmm_param
|| elems
->wmm_info
;
153 bss
->uapsd_supported
= is_uapsd_supported(elems
);
154 if (!elems
->parse_error
)
155 bss
->valid_data
|= IEEE80211_BSS_VALID_WMM
;
159 struct ieee80211_supported_band
*sband
=
160 local
->hw
.wiphy
->bands
[rx_status
->band
];
161 if (!(rx_status
->flag
& RX_FLAG_HT
) &&
162 !(rx_status
->flag
& RX_FLAG_VHT
))
164 &sband
->bitrates
[rx_status
->rate_idx
];
170 void ieee80211_scan_rx(struct ieee80211_local
*local
, struct sk_buff
*skb
)
172 struct ieee80211_rx_status
*rx_status
= IEEE80211_SKB_RXCB(skb
);
173 struct ieee80211_sub_if_data
*sdata1
, *sdata2
;
174 struct ieee80211_mgmt
*mgmt
= (void *)skb
->data
;
175 struct ieee80211_bss
*bss
;
177 struct ieee80211_channel
*channel
;
179 struct ieee802_11_elems elems
;
182 (!ieee80211_is_probe_resp(mgmt
->frame_control
) &&
183 !ieee80211_is_beacon(mgmt
->frame_control
)))
186 sdata1
= rcu_dereference(local
->scan_sdata
);
187 sdata2
= rcu_dereference(local
->sched_scan_sdata
);
189 if (likely(!sdata1
&& !sdata2
))
192 if (ieee80211_is_probe_resp(mgmt
->frame_control
)) {
193 struct cfg80211_scan_request
*scan_req
;
194 struct cfg80211_sched_scan_request
*sched_scan_req
;
196 scan_req
= rcu_dereference(local
->scan_req
);
197 sched_scan_req
= rcu_dereference(local
->sched_scan_req
);
199 /* ignore ProbeResp to foreign address unless scanning
200 * with randomised address
203 (ether_addr_equal(mgmt
->da
, sdata1
->vif
.addr
) ||
204 scan_req
->flags
& NL80211_SCAN_FLAG_RANDOM_ADDR
)) &&
206 (ether_addr_equal(mgmt
->da
, sdata2
->vif
.addr
) ||
207 sched_scan_req
->flags
& NL80211_SCAN_FLAG_RANDOM_ADDR
)))
210 elements
= mgmt
->u
.probe_resp
.variable
;
211 baselen
= offsetof(struct ieee80211_mgmt
, u
.probe_resp
.variable
);
213 baselen
= offsetof(struct ieee80211_mgmt
, u
.beacon
.variable
);
214 elements
= mgmt
->u
.beacon
.variable
;
217 if (baselen
> skb
->len
)
220 ieee802_11_parse_elems(elements
, skb
->len
- baselen
, false, &elems
);
222 channel
= ieee80211_get_channel(local
->hw
.wiphy
, rx_status
->freq
);
224 if (!channel
|| channel
->flags
& IEEE80211_CHAN_DISABLED
)
227 bss
= ieee80211_bss_info_update(local
, rx_status
,
228 mgmt
, skb
->len
, &elems
,
231 ieee80211_rx_bss_put(local
, bss
);
235 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def
*chandef
,
236 enum nl80211_bss_scan_width scan_width
)
238 memset(chandef
, 0, sizeof(*chandef
));
239 switch (scan_width
) {
240 case NL80211_BSS_CHAN_WIDTH_5
:
241 chandef
->width
= NL80211_CHAN_WIDTH_5
;
243 case NL80211_BSS_CHAN_WIDTH_10
:
244 chandef
->width
= NL80211_CHAN_WIDTH_10
;
247 chandef
->width
= NL80211_CHAN_WIDTH_20_NOHT
;
252 /* return false if no more work */
253 static bool ieee80211_prep_hw_scan(struct ieee80211_local
*local
)
255 struct cfg80211_scan_request
*req
;
256 struct cfg80211_chan_def chandef
;
258 int i
, ielen
, n_chans
;
260 req
= rcu_dereference_protected(local
->scan_req
,
261 lockdep_is_held(&local
->mtx
));
263 if (test_bit(SCAN_HW_CANCELLED
, &local
->scanning
))
266 if (ieee80211_hw_check(&local
->hw
, SINGLE_SCAN_ON_ALL_BANDS
)) {
267 for (i
= 0; i
< req
->n_channels
; i
++) {
268 local
->hw_scan_req
->req
.channels
[i
] = req
->channels
[i
];
269 bands_used
|= BIT(req
->channels
[i
]->band
);
272 n_chans
= req
->n_channels
;
275 if (local
->hw_scan_band
== NUM_NL80211_BANDS
)
280 for (i
= 0; i
< req
->n_channels
; i
++) {
281 if (req
->channels
[i
]->band
!=
284 local
->hw_scan_req
->req
.channels
[n_chans
] =
287 bands_used
|= BIT(req
->channels
[i
]->band
);
290 local
->hw_scan_band
++;
294 local
->hw_scan_req
->req
.n_channels
= n_chans
;
295 ieee80211_prepare_scan_chandef(&chandef
, req
->scan_width
);
297 ielen
= ieee80211_build_preq_ies(local
,
298 (u8
*)local
->hw_scan_req
->req
.ie
,
299 local
->hw_scan_ies_bufsize
,
300 &local
->hw_scan_req
->ies
,
301 req
->ie
, req
->ie_len
,
302 bands_used
, req
->rates
, &chandef
);
303 local
->hw_scan_req
->req
.ie_len
= ielen
;
304 local
->hw_scan_req
->req
.no_cck
= req
->no_cck
;
305 ether_addr_copy(local
->hw_scan_req
->req
.mac_addr
, req
->mac_addr
);
306 ether_addr_copy(local
->hw_scan_req
->req
.mac_addr_mask
,
308 ether_addr_copy(local
->hw_scan_req
->req
.bssid
, req
->bssid
);
313 static void __ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
)
315 struct ieee80211_local
*local
= hw_to_local(hw
);
316 bool hw_scan
= local
->ops
->hw_scan
;
317 bool was_scanning
= local
->scanning
;
318 struct cfg80211_scan_request
*scan_req
;
319 struct ieee80211_sub_if_data
*scan_sdata
;
320 struct ieee80211_sub_if_data
*sdata
;
322 lockdep_assert_held(&local
->mtx
);
325 * It's ok to abort a not-yet-running scan (that
326 * we have one at all will be verified by checking
327 * local->scan_req next), but not to complete it
330 if (WARN_ON(!local
->scanning
&& !aborted
))
333 if (WARN_ON(!local
->scan_req
))
336 if (hw_scan
&& !aborted
&&
337 !ieee80211_hw_check(&local
->hw
, SINGLE_SCAN_ON_ALL_BANDS
) &&
338 ieee80211_prep_hw_scan(local
)) {
341 rc
= drv_hw_scan(local
,
342 rcu_dereference_protected(local
->scan_sdata
,
343 lockdep_is_held(&local
->mtx
)),
350 kfree(local
->hw_scan_req
);
351 local
->hw_scan_req
= NULL
;
353 scan_req
= rcu_dereference_protected(local
->scan_req
,
354 lockdep_is_held(&local
->mtx
));
356 if (scan_req
!= local
->int_scan_req
)
357 cfg80211_scan_done(scan_req
, aborted
);
358 RCU_INIT_POINTER(local
->scan_req
, NULL
);
360 scan_sdata
= rcu_dereference_protected(local
->scan_sdata
,
361 lockdep_is_held(&local
->mtx
));
362 RCU_INIT_POINTER(local
->scan_sdata
, NULL
);
365 local
->scan_chandef
.chan
= NULL
;
367 /* Set power back to normal operating levels. */
368 ieee80211_hw_config(local
, 0);
371 ieee80211_configure_filter(local
);
372 drv_sw_scan_complete(local
, scan_sdata
);
373 ieee80211_offchannel_return(local
);
376 ieee80211_recalc_idle(local
);
378 ieee80211_mlme_notify_scan_completed(local
);
379 ieee80211_ibss_notify_scan_completed(local
);
381 /* Requeue all the work that might have been ignored while
382 * the scan was in progress; if there was none this will
383 * just be a no-op for the particular interface.
385 list_for_each_entry_rcu(sdata
, &local
->interfaces
, list
) {
386 if (ieee80211_sdata_running(sdata
))
387 ieee80211_queue_work(&sdata
->local
->hw
, &sdata
->work
);
391 ieee80211_start_next_roc(local
);
394 void ieee80211_scan_completed(struct ieee80211_hw
*hw
, bool aborted
)
396 struct ieee80211_local
*local
= hw_to_local(hw
);
398 trace_api_scan_completed(local
, aborted
);
400 set_bit(SCAN_COMPLETED
, &local
->scanning
);
402 set_bit(SCAN_ABORTED
, &local
->scanning
);
403 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, 0);
405 EXPORT_SYMBOL(ieee80211_scan_completed
);
407 static int ieee80211_start_sw_scan(struct ieee80211_local
*local
,
408 struct ieee80211_sub_if_data
*sdata
)
410 /* Software scan is not supported in multi-channel cases */
411 if (local
->use_chanctx
)
415 * Hardware/driver doesn't support hw_scan, so use software
416 * scanning instead. First send a nullfunc frame with power save
417 * bit on so that AP will buffer the frames for us while we are not
418 * listening, then send probe requests to each channel and wait for
419 * the responses. After all channels are scanned, tune back to the
420 * original channel and send a nullfunc frame with power save bit
421 * off to trigger the AP to send us all the buffered frames.
423 * Note that while local->sw_scanning is true everything else but
424 * nullfunc frames and probe requests will be dropped in
425 * ieee80211_tx_h_check_assoc().
427 drv_sw_scan_start(local
, sdata
, local
->scan_addr
);
429 local
->leave_oper_channel_time
= jiffies
;
430 local
->next_scan_state
= SCAN_DECISION
;
431 local
->scan_channel_idx
= 0;
433 ieee80211_offchannel_stop_vifs(local
);
435 /* ensure nullfunc is transmitted before leaving operating channel */
436 ieee80211_flush_queues(local
, NULL
, false);
438 ieee80211_configure_filter(local
);
440 /* We need to set power level at maximum rate for scanning. */
441 ieee80211_hw_config(local
, 0);
443 ieee80211_queue_delayed_work(&local
->hw
,
444 &local
->scan_work
, 0);
449 static bool ieee80211_can_scan(struct ieee80211_local
*local
,
450 struct ieee80211_sub_if_data
*sdata
)
452 if (ieee80211_is_radar_required(local
))
455 if (!list_empty(&local
->roc_list
))
458 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
&&
459 sdata
->u
.mgd
.flags
& IEEE80211_STA_CONNECTION_POLL
)
465 void ieee80211_run_deferred_scan(struct ieee80211_local
*local
)
467 lockdep_assert_held(&local
->mtx
);
469 if (!local
->scan_req
|| local
->scanning
)
472 if (!ieee80211_can_scan(local
,
473 rcu_dereference_protected(
475 lockdep_is_held(&local
->mtx
))))
478 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
479 round_jiffies_relative(0));
482 static void ieee80211_scan_state_send_probe(struct ieee80211_local
*local
,
483 unsigned long *next_delay
)
486 struct ieee80211_sub_if_data
*sdata
;
487 struct cfg80211_scan_request
*scan_req
;
488 enum nl80211_band band
= local
->hw
.conf
.chandef
.chan
->band
;
491 scan_req
= rcu_dereference_protected(local
->scan_req
,
492 lockdep_is_held(&local
->mtx
));
494 tx_flags
= IEEE80211_TX_INTFL_OFFCHAN_TX_OK
;
495 if (scan_req
->no_cck
)
496 tx_flags
|= IEEE80211_TX_CTL_NO_CCK_RATE
;
498 sdata
= rcu_dereference_protected(local
->scan_sdata
,
499 lockdep_is_held(&local
->mtx
));
501 for (i
= 0; i
< scan_req
->n_ssids
; i
++)
502 ieee80211_send_probe_req(
503 sdata
, local
->scan_addr
, scan_req
->bssid
,
504 scan_req
->ssids
[i
].ssid
, scan_req
->ssids
[i
].ssid_len
,
505 scan_req
->ie
, scan_req
->ie_len
,
506 scan_req
->rates
[band
], false,
507 tx_flags
, local
->hw
.conf
.chandef
.chan
, true);
510 * After sending probe requests, wait for probe responses
513 *next_delay
= IEEE80211_CHANNEL_TIME
;
514 local
->next_scan_state
= SCAN_DECISION
;
517 static int __ieee80211_start_scan(struct ieee80211_sub_if_data
*sdata
,
518 struct cfg80211_scan_request
*req
)
520 struct ieee80211_local
*local
= sdata
->local
;
523 lockdep_assert_held(&local
->mtx
);
525 if (local
->scan_req
|| ieee80211_is_radar_required(local
))
528 if (!ieee80211_can_scan(local
, sdata
)) {
529 /* wait for the work to finish/time out */
530 rcu_assign_pointer(local
->scan_req
, req
);
531 rcu_assign_pointer(local
->scan_sdata
, sdata
);
535 if (local
->ops
->hw_scan
) {
538 local
->hw_scan_ies_bufsize
= local
->scan_ies_len
+ req
->ie_len
;
540 if (ieee80211_hw_check(&local
->hw
, SINGLE_SCAN_ON_ALL_BANDS
)) {
542 u8 bands_counted
= 0;
544 for (i
= 0; i
< req
->n_channels
; i
++) {
545 if (bands_counted
& BIT(req
->channels
[i
]->band
))
547 bands_counted
|= BIT(req
->channels
[i
]->band
);
551 local
->hw_scan_ies_bufsize
*= n_bands
;
554 local
->hw_scan_req
= kmalloc(
555 sizeof(*local
->hw_scan_req
) +
556 req
->n_channels
* sizeof(req
->channels
[0]) +
557 local
->hw_scan_ies_bufsize
, GFP_KERNEL
);
558 if (!local
->hw_scan_req
)
561 local
->hw_scan_req
->req
.ssids
= req
->ssids
;
562 local
->hw_scan_req
->req
.n_ssids
= req
->n_ssids
;
563 ies
= (u8
*)local
->hw_scan_req
+
564 sizeof(*local
->hw_scan_req
) +
565 req
->n_channels
* sizeof(req
->channels
[0]);
566 local
->hw_scan_req
->req
.ie
= ies
;
567 local
->hw_scan_req
->req
.flags
= req
->flags
;
568 eth_broadcast_addr(local
->hw_scan_req
->req
.bssid
);
570 local
->hw_scan_band
= 0;
573 * After allocating local->hw_scan_req, we must
574 * go through until ieee80211_prep_hw_scan(), so
575 * anything that might be changed here and leave
576 * this function early must not go after this
581 rcu_assign_pointer(local
->scan_req
, req
);
582 rcu_assign_pointer(local
->scan_sdata
, sdata
);
584 if (req
->flags
& NL80211_SCAN_FLAG_RANDOM_ADDR
)
585 get_random_mask_addr(local
->scan_addr
,
589 memcpy(local
->scan_addr
, sdata
->vif
.addr
, ETH_ALEN
);
591 if (local
->ops
->hw_scan
) {
592 __set_bit(SCAN_HW_SCANNING
, &local
->scanning
);
593 } else if ((req
->n_channels
== 1) &&
594 (req
->channels
[0] == local
->_oper_chandef
.chan
)) {
596 * If we are scanning only on the operating channel
597 * then we do not need to stop normal activities
599 unsigned long next_delay
;
601 __set_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
);
603 ieee80211_recalc_idle(local
);
605 /* Notify driver scan is starting, keep order of operations
606 * same as normal software scan, in case that matters. */
607 drv_sw_scan_start(local
, sdata
, local
->scan_addr
);
609 ieee80211_configure_filter(local
); /* accept probe-responses */
611 /* We need to ensure power level is at max for scanning. */
612 ieee80211_hw_config(local
, 0);
614 if ((req
->channels
[0]->flags
& (IEEE80211_CHAN_NO_IR
|
615 IEEE80211_CHAN_RADAR
)) ||
617 next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
619 ieee80211_scan_state_send_probe(local
, &next_delay
);
620 next_delay
= IEEE80211_CHANNEL_TIME
;
623 /* Now, just wait a bit and we are all done! */
624 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
,
628 /* Do normal software scan */
629 __set_bit(SCAN_SW_SCANNING
, &local
->scanning
);
632 ieee80211_recalc_idle(local
);
634 if (local
->ops
->hw_scan
) {
635 WARN_ON(!ieee80211_prep_hw_scan(local
));
636 rc
= drv_hw_scan(local
, sdata
, local
->hw_scan_req
);
638 rc
= ieee80211_start_sw_scan(local
, sdata
);
642 kfree(local
->hw_scan_req
);
643 local
->hw_scan_req
= NULL
;
646 ieee80211_recalc_idle(local
);
648 local
->scan_req
= NULL
;
649 RCU_INIT_POINTER(local
->scan_sdata
, NULL
);
656 ieee80211_scan_get_channel_time(struct ieee80211_channel
*chan
)
659 * TODO: channel switching also consumes quite some time,
660 * add that delay as well to get a better estimation
662 if (chan
->flags
& (IEEE80211_CHAN_NO_IR
| IEEE80211_CHAN_RADAR
))
663 return IEEE80211_PASSIVE_CHANNEL_TIME
;
664 return IEEE80211_PROBE_DELAY
+ IEEE80211_CHANNEL_TIME
;
667 static void ieee80211_scan_state_decision(struct ieee80211_local
*local
,
668 unsigned long *next_delay
)
670 bool associated
= false;
671 bool tx_empty
= true;
673 struct ieee80211_sub_if_data
*sdata
;
674 struct ieee80211_channel
*next_chan
;
675 enum mac80211_scan_state next_scan_state
;
676 struct cfg80211_scan_request
*scan_req
;
679 * check if at least one STA interface is associated,
680 * check if at least one STA interface has pending tx frames
681 * and grab the lowest used beacon interval
683 mutex_lock(&local
->iflist_mtx
);
684 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
685 if (!ieee80211_sdata_running(sdata
))
688 if (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
689 if (sdata
->u
.mgd
.associated
) {
692 if (!qdisc_all_tx_empty(sdata
->dev
)) {
699 mutex_unlock(&local
->iflist_mtx
);
701 scan_req
= rcu_dereference_protected(local
->scan_req
,
702 lockdep_is_held(&local
->mtx
));
704 next_chan
= scan_req
->channels
[local
->scan_channel_idx
];
707 * we're currently scanning a different channel, let's
708 * see if we can scan another channel without interfering
709 * with the current traffic situation.
711 * Keep good latency, do not stay off-channel more than 125 ms.
714 bad_latency
= time_after(jiffies
+
715 ieee80211_scan_get_channel_time(next_chan
),
716 local
->leave_oper_channel_time
+ HZ
/ 8);
718 if (associated
&& !tx_empty
) {
719 if (scan_req
->flags
& NL80211_SCAN_FLAG_LOW_PRIORITY
)
720 next_scan_state
= SCAN_ABORT
;
722 next_scan_state
= SCAN_SUSPEND
;
723 } else if (associated
&& bad_latency
) {
724 next_scan_state
= SCAN_SUSPEND
;
726 next_scan_state
= SCAN_SET_CHANNEL
;
729 local
->next_scan_state
= next_scan_state
;
734 static void ieee80211_scan_state_set_channel(struct ieee80211_local
*local
,
735 unsigned long *next_delay
)
738 struct ieee80211_channel
*chan
;
739 enum nl80211_bss_scan_width oper_scan_width
;
740 struct cfg80211_scan_request
*scan_req
;
742 scan_req
= rcu_dereference_protected(local
->scan_req
,
743 lockdep_is_held(&local
->mtx
));
746 chan
= scan_req
->channels
[local
->scan_channel_idx
];
748 local
->scan_chandef
.chan
= chan
;
749 local
->scan_chandef
.center_freq1
= chan
->center_freq
;
750 local
->scan_chandef
.center_freq2
= 0;
751 switch (scan_req
->scan_width
) {
752 case NL80211_BSS_CHAN_WIDTH_5
:
753 local
->scan_chandef
.width
= NL80211_CHAN_WIDTH_5
;
755 case NL80211_BSS_CHAN_WIDTH_10
:
756 local
->scan_chandef
.width
= NL80211_CHAN_WIDTH_10
;
758 case NL80211_BSS_CHAN_WIDTH_20
:
759 /* If scanning on oper channel, use whatever channel-type
760 * is currently in use.
762 oper_scan_width
= cfg80211_chandef_to_scan_width(
763 &local
->_oper_chandef
);
764 if (chan
== local
->_oper_chandef
.chan
&&
765 oper_scan_width
== scan_req
->scan_width
)
766 local
->scan_chandef
= local
->_oper_chandef
;
768 local
->scan_chandef
.width
= NL80211_CHAN_WIDTH_20_NOHT
;
772 if (ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
))
775 /* advance state machine to next channel/band */
776 local
->scan_channel_idx
++;
779 /* if we skip this channel return to the decision state */
780 local
->next_scan_state
= SCAN_DECISION
;
785 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
786 * (which unfortunately doesn't say _why_ step a) is done,
787 * but it waits for the probe delay or until a frame is
788 * received - and the received frame would update the NAV).
789 * For now, we do not support waiting until a frame is
792 * In any case, it is not necessary for a passive scan.
794 if ((chan
->flags
& (IEEE80211_CHAN_NO_IR
| IEEE80211_CHAN_RADAR
)) ||
795 !scan_req
->n_ssids
) {
796 *next_delay
= IEEE80211_PASSIVE_CHANNEL_TIME
;
797 local
->next_scan_state
= SCAN_DECISION
;
801 /* active scan, send probes */
802 *next_delay
= IEEE80211_PROBE_DELAY
;
803 local
->next_scan_state
= SCAN_SEND_PROBE
;
806 static void ieee80211_scan_state_suspend(struct ieee80211_local
*local
,
807 unsigned long *next_delay
)
809 /* switch back to the operating channel */
810 local
->scan_chandef
.chan
= NULL
;
811 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_CHANNEL
);
814 ieee80211_offchannel_return(local
);
816 *next_delay
= HZ
/ 5;
817 /* afterwards, resume scan & go to next channel */
818 local
->next_scan_state
= SCAN_RESUME
;
821 static void ieee80211_scan_state_resume(struct ieee80211_local
*local
,
822 unsigned long *next_delay
)
824 ieee80211_offchannel_stop_vifs(local
);
826 if (local
->ops
->flush
) {
827 ieee80211_flush_queues(local
, NULL
, false);
830 *next_delay
= HZ
/ 10;
832 /* remember when we left the operating channel */
833 local
->leave_oper_channel_time
= jiffies
;
835 /* advance to the next channel to be scanned */
836 local
->next_scan_state
= SCAN_SET_CHANNEL
;
839 void ieee80211_scan_work(struct work_struct
*work
)
841 struct ieee80211_local
*local
=
842 container_of(work
, struct ieee80211_local
, scan_work
.work
);
843 struct ieee80211_sub_if_data
*sdata
;
844 struct cfg80211_scan_request
*scan_req
;
845 unsigned long next_delay
= 0;
848 mutex_lock(&local
->mtx
);
850 if (!ieee80211_can_run_worker(local
)) {
855 sdata
= rcu_dereference_protected(local
->scan_sdata
,
856 lockdep_is_held(&local
->mtx
));
857 scan_req
= rcu_dereference_protected(local
->scan_req
,
858 lockdep_is_held(&local
->mtx
));
860 /* When scanning on-channel, the first-callback means completed. */
861 if (test_bit(SCAN_ONCHANNEL_SCANNING
, &local
->scanning
)) {
862 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
866 if (test_and_clear_bit(SCAN_COMPLETED
, &local
->scanning
)) {
867 aborted
= test_and_clear_bit(SCAN_ABORTED
, &local
->scanning
);
871 if (!sdata
|| !scan_req
)
874 if (!local
->scanning
) {
877 RCU_INIT_POINTER(local
->scan_req
, NULL
);
878 RCU_INIT_POINTER(local
->scan_sdata
, NULL
);
880 rc
= __ieee80211_start_scan(sdata
, scan_req
);
882 /* need to complete scan in cfg80211 */
883 rcu_assign_pointer(local
->scan_req
, scan_req
);
891 * as long as no delay is required advance immediately
892 * without scheduling a new work
895 if (!ieee80211_sdata_running(sdata
)) {
900 switch (local
->next_scan_state
) {
902 /* if no more bands/channels left, complete scan */
903 if (local
->scan_channel_idx
>= scan_req
->n_channels
) {
907 ieee80211_scan_state_decision(local
, &next_delay
);
909 case SCAN_SET_CHANNEL
:
910 ieee80211_scan_state_set_channel(local
, &next_delay
);
912 case SCAN_SEND_PROBE
:
913 ieee80211_scan_state_send_probe(local
, &next_delay
);
916 ieee80211_scan_state_suspend(local
, &next_delay
);
919 ieee80211_scan_state_resume(local
, &next_delay
);
925 } while (next_delay
== 0);
927 ieee80211_queue_delayed_work(&local
->hw
, &local
->scan_work
, next_delay
);
931 __ieee80211_scan_completed(&local
->hw
, aborted
);
933 mutex_unlock(&local
->mtx
);
936 int ieee80211_request_scan(struct ieee80211_sub_if_data
*sdata
,
937 struct cfg80211_scan_request
*req
)
941 mutex_lock(&sdata
->local
->mtx
);
942 res
= __ieee80211_start_scan(sdata
, req
);
943 mutex_unlock(&sdata
->local
->mtx
);
948 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data
*sdata
,
949 const u8
*ssid
, u8 ssid_len
,
950 struct ieee80211_channel
**channels
,
951 unsigned int n_channels
,
952 enum nl80211_bss_scan_width scan_width
)
954 struct ieee80211_local
*local
= sdata
->local
;
955 int ret
= -EBUSY
, i
, n_ch
= 0;
956 enum nl80211_band band
;
958 mutex_lock(&local
->mtx
);
964 /* fill internal scan request */
968 for (band
= 0; band
< NUM_NL80211_BANDS
; band
++) {
969 if (!local
->hw
.wiphy
->bands
[band
])
972 max_n
= local
->hw
.wiphy
->bands
[band
]->n_channels
;
973 for (i
= 0; i
< max_n
; i
++) {
974 struct ieee80211_channel
*tmp_ch
=
975 &local
->hw
.wiphy
->bands
[band
]->channels
[i
];
977 if (tmp_ch
->flags
& (IEEE80211_CHAN_NO_IR
|
978 IEEE80211_CHAN_DISABLED
))
981 local
->int_scan_req
->channels
[n_ch
] = tmp_ch
;
986 if (WARN_ON_ONCE(n_ch
== 0))
989 local
->int_scan_req
->n_channels
= n_ch
;
991 for (i
= 0; i
< n_channels
; i
++) {
992 if (channels
[i
]->flags
& (IEEE80211_CHAN_NO_IR
|
993 IEEE80211_CHAN_DISABLED
))
996 local
->int_scan_req
->channels
[n_ch
] = channels
[i
];
1000 if (WARN_ON_ONCE(n_ch
== 0))
1003 local
->int_scan_req
->n_channels
= n_ch
;
1006 local
->int_scan_req
->ssids
= &local
->scan_ssid
;
1007 local
->int_scan_req
->n_ssids
= 1;
1008 local
->int_scan_req
->scan_width
= scan_width
;
1009 memcpy(local
->int_scan_req
->ssids
[0].ssid
, ssid
, IEEE80211_MAX_SSID_LEN
);
1010 local
->int_scan_req
->ssids
[0].ssid_len
= ssid_len
;
1012 ret
= __ieee80211_start_scan(sdata
, sdata
->local
->int_scan_req
);
1014 mutex_unlock(&local
->mtx
);
1019 * Only call this function when a scan can't be queued -- under RTNL.
1021 void ieee80211_scan_cancel(struct ieee80211_local
*local
)
1024 * We are canceling software scan, or deferred scan that was not
1025 * yet really started (see __ieee80211_start_scan ).
1027 * Regarding hardware scan:
1028 * - we can not call __ieee80211_scan_completed() as when
1029 * SCAN_HW_SCANNING bit is set this function change
1030 * local->hw_scan_req to operate on 5G band, what race with
1031 * driver which can use local->hw_scan_req
1033 * - we can not cancel scan_work since driver can schedule it
1034 * by ieee80211_scan_completed(..., true) to finish scan
1036 * Hence we only call the cancel_hw_scan() callback, but the low-level
1037 * driver is still responsible for calling ieee80211_scan_completed()
1038 * after the scan was completed/aborted.
1041 mutex_lock(&local
->mtx
);
1042 if (!local
->scan_req
)
1046 * We have a scan running and the driver already reported completion,
1047 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1050 if (test_bit(SCAN_HW_SCANNING
, &local
->scanning
) &&
1051 test_bit(SCAN_COMPLETED
, &local
->scanning
)) {
1052 set_bit(SCAN_HW_CANCELLED
, &local
->scanning
);
1056 if (test_bit(SCAN_HW_SCANNING
, &local
->scanning
)) {
1058 * Make sure that __ieee80211_scan_completed doesn't trigger a
1059 * scan on another band.
1061 set_bit(SCAN_HW_CANCELLED
, &local
->scanning
);
1062 if (local
->ops
->cancel_hw_scan
)
1063 drv_cancel_hw_scan(local
,
1064 rcu_dereference_protected(local
->scan_sdata
,
1065 lockdep_is_held(&local
->mtx
)));
1070 * If the work is currently running, it must be blocked on
1071 * the mutex, but we'll set scan_sdata = NULL and it'll
1072 * simply exit once it acquires the mutex.
1074 cancel_delayed_work(&local
->scan_work
);
1076 __ieee80211_scan_completed(&local
->hw
, true);
1078 mutex_unlock(&local
->mtx
);
1081 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data
*sdata
,
1082 struct cfg80211_sched_scan_request
*req
)
1084 struct ieee80211_local
*local
= sdata
->local
;
1085 struct ieee80211_scan_ies sched_scan_ies
= {};
1086 struct cfg80211_chan_def chandef
;
1087 int ret
, i
, iebufsz
, num_bands
= 0;
1088 u32 rate_masks
[NUM_NL80211_BANDS
] = {};
1093 iebufsz
= local
->scan_ies_len
+ req
->ie_len
;
1095 lockdep_assert_held(&local
->mtx
);
1097 if (!local
->ops
->sched_scan_start
)
1100 for (i
= 0; i
< NUM_NL80211_BANDS
; i
++) {
1101 if (local
->hw
.wiphy
->bands
[i
]) {
1102 bands_used
|= BIT(i
);
1103 rate_masks
[i
] = (u32
) -1;
1108 ie
= kzalloc(num_bands
* iebufsz
, GFP_KERNEL
);
1114 ieee80211_prepare_scan_chandef(&chandef
, req
->scan_width
);
1116 len
= ieee80211_build_preq_ies(local
, ie
, num_bands
* iebufsz
,
1117 &sched_scan_ies
, req
->ie
,
1118 req
->ie_len
, bands_used
,
1119 rate_masks
, &chandef
);
1121 ret
= drv_sched_scan_start(local
, sdata
, req
, &sched_scan_ies
);
1123 rcu_assign_pointer(local
->sched_scan_sdata
, sdata
);
1124 rcu_assign_pointer(local
->sched_scan_req
, req
);
1131 /* Clean in case of failure after HW restart or upon resume. */
1132 RCU_INIT_POINTER(local
->sched_scan_sdata
, NULL
);
1133 RCU_INIT_POINTER(local
->sched_scan_req
, NULL
);
1139 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data
*sdata
,
1140 struct cfg80211_sched_scan_request
*req
)
1142 struct ieee80211_local
*local
= sdata
->local
;
1145 mutex_lock(&local
->mtx
);
1147 if (rcu_access_pointer(local
->sched_scan_sdata
)) {
1148 mutex_unlock(&local
->mtx
);
1152 ret
= __ieee80211_request_sched_scan_start(sdata
, req
);
1154 mutex_unlock(&local
->mtx
);
1158 int ieee80211_request_sched_scan_stop(struct ieee80211_local
*local
)
1160 struct ieee80211_sub_if_data
*sched_scan_sdata
;
1163 mutex_lock(&local
->mtx
);
1165 if (!local
->ops
->sched_scan_stop
) {
1170 /* We don't want to restart sched scan anymore. */
1171 RCU_INIT_POINTER(local
->sched_scan_req
, NULL
);
1173 sched_scan_sdata
= rcu_dereference_protected(local
->sched_scan_sdata
,
1174 lockdep_is_held(&local
->mtx
));
1175 if (sched_scan_sdata
) {
1176 ret
= drv_sched_scan_stop(local
, sched_scan_sdata
);
1178 RCU_INIT_POINTER(local
->sched_scan_sdata
, NULL
);
1181 mutex_unlock(&local
->mtx
);
1186 void ieee80211_sched_scan_results(struct ieee80211_hw
*hw
)
1188 struct ieee80211_local
*local
= hw_to_local(hw
);
1190 trace_api_sched_scan_results(local
);
1192 cfg80211_sched_scan_results(hw
->wiphy
);
1194 EXPORT_SYMBOL(ieee80211_sched_scan_results
);
1196 void ieee80211_sched_scan_end(struct ieee80211_local
*local
)
1198 mutex_lock(&local
->mtx
);
1200 if (!rcu_access_pointer(local
->sched_scan_sdata
)) {
1201 mutex_unlock(&local
->mtx
);
1205 RCU_INIT_POINTER(local
->sched_scan_sdata
, NULL
);
1207 /* If sched scan was aborted by the driver. */
1208 RCU_INIT_POINTER(local
->sched_scan_req
, NULL
);
1210 mutex_unlock(&local
->mtx
);
1212 cfg80211_sched_scan_stopped(local
->hw
.wiphy
);
1215 void ieee80211_sched_scan_stopped_work(struct work_struct
*work
)
1217 struct ieee80211_local
*local
=
1218 container_of(work
, struct ieee80211_local
,
1219 sched_scan_stopped_work
);
1221 ieee80211_sched_scan_end(local
);
1224 void ieee80211_sched_scan_stopped(struct ieee80211_hw
*hw
)
1226 struct ieee80211_local
*local
= hw_to_local(hw
);
1228 trace_api_sched_scan_stopped(local
);
1231 * this shouldn't really happen, so for simplicity
1232 * simply ignore it, and let mac80211 reconfigure
1233 * the sched scan later on.
1235 if (local
->in_reconfig
)
1238 schedule_work(&local
->sched_scan_stopped_work
);
1240 EXPORT_SYMBOL(ieee80211_sched_scan_stopped
);