2 * Off-channel operation helpers
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 2009 Johannes Berg <johannes@sipsolutions.net>
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.
15 #include <linux/export.h>
16 #include <net/mac80211.h>
17 #include "ieee80211_i.h"
18 #include "driver-ops.h"
21 * Tell our hardware to disable PS.
22 * Optionally inform AP that we will go to sleep so that it will buffer
23 * the frames while we are doing off-channel work. This is optional
24 * because we *may* be doing work on-operating channel, and want our
25 * hardware unconditionally awake, but still let the AP send us normal frames.
27 static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data
*sdata
)
29 struct ieee80211_local
*local
= sdata
->local
;
30 struct ieee80211_if_managed
*ifmgd
= &sdata
->u
.mgd
;
32 local
->offchannel_ps_enabled
= false;
34 /* FIXME: what to do when local->pspolling is true? */
36 del_timer_sync(&local
->dynamic_ps_timer
);
37 del_timer_sync(&ifmgd
->bcn_mon_timer
);
38 del_timer_sync(&ifmgd
->conn_mon_timer
);
40 cancel_work_sync(&local
->dynamic_ps_enable_work
);
42 if (local
->hw
.conf
.flags
& IEEE80211_CONF_PS
) {
43 local
->offchannel_ps_enabled
= true;
44 local
->hw
.conf
.flags
&= ~IEEE80211_CONF_PS
;
45 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_PS
);
48 if (!local
->offchannel_ps_enabled
||
49 !(local
->hw
.flags
& IEEE80211_HW_PS_NULLFUNC_STACK
))
51 * If power save was enabled, no need to send a nullfunc
52 * frame because AP knows that we are sleeping. But if the
53 * hardware is creating the nullfunc frame for power save
54 * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
55 * enabled) and power save was enabled, the firmware just
56 * sent a null frame with power save disabled. So we need
57 * to send a new nullfunc frame to inform the AP that we
60 ieee80211_send_nullfunc(local
, sdata
, 1);
63 /* inform AP that we are awake again, unless power save is enabled */
64 static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data
*sdata
)
66 struct ieee80211_local
*local
= sdata
->local
;
69 ieee80211_send_nullfunc(local
, sdata
, 0);
70 else if (local
->offchannel_ps_enabled
) {
72 * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware
73 * will send a nullfunc frame with the powersave bit set
74 * even though the AP already knows that we are sleeping.
75 * This could be avoided by sending a null frame with power
76 * save bit disabled before enabling the power save, but
77 * this doesn't gain anything.
79 * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need
80 * to send a nullfunc frame because AP already knows that
81 * we are sleeping, let's just enable power save mode in
84 /* TODO: Only set hardware if CONF_PS changed?
85 * TODO: Should we set offchannel_ps_enabled to false?
87 local
->hw
.conf
.flags
|= IEEE80211_CONF_PS
;
88 ieee80211_hw_config(local
, IEEE80211_CONF_CHANGE_PS
);
89 } else if (local
->hw
.conf
.dynamic_ps_timeout
> 0) {
91 * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer
92 * had been running before leaving the operating channel,
93 * restart the timer now and send a nullfunc frame to inform
94 * the AP that we are awake.
96 ieee80211_send_nullfunc(local
, sdata
, 0);
97 mod_timer(&local
->dynamic_ps_timer
, jiffies
+
98 msecs_to_jiffies(local
->hw
.conf
.dynamic_ps_timeout
));
101 ieee80211_sta_reset_beacon_monitor(sdata
);
102 ieee80211_sta_reset_conn_monitor(sdata
);
105 void ieee80211_offchannel_stop_vifs(struct ieee80211_local
*local
,
106 bool offchannel_ps_enable
)
108 struct ieee80211_sub_if_data
*sdata
;
111 * notify the AP about us leaving the channel and stop all
114 mutex_lock(&local
->iflist_mtx
);
115 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
116 if (!ieee80211_sdata_running(sdata
))
119 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
)
120 set_bit(SDATA_STATE_OFFCHANNEL
, &sdata
->state
);
122 /* Check to see if we should disable beaconing. */
123 if (sdata
->vif
.type
== NL80211_IFTYPE_AP
||
124 sdata
->vif
.type
== NL80211_IFTYPE_ADHOC
||
125 sdata
->vif
.type
== NL80211_IFTYPE_MESH_POINT
)
126 ieee80211_bss_info_change_notify(
127 sdata
, BSS_CHANGED_BEACON_ENABLED
);
129 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
) {
130 netif_tx_stop_all_queues(sdata
->dev
);
131 if (offchannel_ps_enable
&&
132 (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) &&
133 sdata
->u
.mgd
.associated
)
134 ieee80211_offchannel_ps_enable(sdata
);
137 mutex_unlock(&local
->iflist_mtx
);
140 void ieee80211_offchannel_return(struct ieee80211_local
*local
,
141 bool offchannel_ps_disable
)
143 struct ieee80211_sub_if_data
*sdata
;
145 mutex_lock(&local
->iflist_mtx
);
146 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
147 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
)
148 clear_bit(SDATA_STATE_OFFCHANNEL
, &sdata
->state
);
150 if (!ieee80211_sdata_running(sdata
))
153 /* Tell AP we're back */
154 if (offchannel_ps_disable
&&
155 sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
156 if (sdata
->u
.mgd
.associated
)
157 ieee80211_offchannel_ps_disable(sdata
);
160 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
) {
162 * This may wake up queues even though the driver
163 * currently has them stopped. This is not very
164 * likely, since the driver won't have gotten any
165 * (or hardly any) new packets while we weren't
166 * on the right channel, and even if it happens
167 * it will at most lead to queueing up one more
168 * packet per queue in mac80211 rather than on
169 * the interface qdisc.
171 netif_tx_wake_all_queues(sdata
->dev
);
174 if (sdata
->vif
.type
== NL80211_IFTYPE_AP
||
175 sdata
->vif
.type
== NL80211_IFTYPE_ADHOC
||
176 sdata
->vif
.type
== NL80211_IFTYPE_MESH_POINT
)
177 ieee80211_bss_info_change_notify(
178 sdata
, BSS_CHANGED_BEACON_ENABLED
);
180 mutex_unlock(&local
->iflist_mtx
);
183 void ieee80211_handle_roc_started(struct ieee80211_roc_work
*roc
)
188 if (roc
->mgmt_tx_cookie
) {
189 if (!WARN_ON(!roc
->frame
)) {
190 ieee80211_tx_skb(roc
->sdata
, roc
->frame
);
194 cfg80211_ready_on_channel(&roc
->sdata
->wdev
, (unsigned long)roc
,
195 roc
->chan
, roc
->chan_type
,
196 roc
->req_duration
, GFP_KERNEL
);
199 roc
->notified
= true;
202 static void ieee80211_hw_roc_start(struct work_struct
*work
)
204 struct ieee80211_local
*local
=
205 container_of(work
, struct ieee80211_local
, hw_roc_start
);
206 struct ieee80211_roc_work
*roc
, *dep
, *tmp
;
208 mutex_lock(&local
->mtx
);
210 if (list_empty(&local
->roc_list
))
213 roc
= list_first_entry(&local
->roc_list
, struct ieee80211_roc_work
,
219 roc
->hw_begun
= true;
220 roc
->hw_start_time
= local
->hw_roc_start_time
;
222 ieee80211_handle_roc_started(roc
);
223 list_for_each_entry_safe(dep
, tmp
, &roc
->dependents
, list
) {
224 ieee80211_handle_roc_started(dep
);
226 if (dep
->duration
> roc
->duration
) {
227 u32 dur
= dep
->duration
;
228 dep
->duration
= dur
- roc
->duration
;
230 list_del(&dep
->list
);
231 list_add(&dep
->list
, &roc
->list
);
235 mutex_unlock(&local
->mtx
);
238 void ieee80211_ready_on_channel(struct ieee80211_hw
*hw
)
240 struct ieee80211_local
*local
= hw_to_local(hw
);
242 local
->hw_roc_start_time
= jiffies
;
244 trace_api_ready_on_channel(local
);
246 ieee80211_queue_work(hw
, &local
->hw_roc_start
);
248 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel
);
250 void ieee80211_start_next_roc(struct ieee80211_local
*local
)
252 struct ieee80211_roc_work
*roc
;
254 lockdep_assert_held(&local
->mtx
);
256 if (list_empty(&local
->roc_list
)) {
257 ieee80211_run_deferred_scan(local
);
261 roc
= list_first_entry(&local
->roc_list
, struct ieee80211_roc_work
,
264 if (WARN_ON_ONCE(roc
->started
))
267 if (local
->ops
->remain_on_channel
) {
268 int ret
, duration
= roc
->duration
;
270 /* XXX: duplicated, see ieee80211_start_roc_work() */
274 ret
= drv_remain_on_channel(local
, roc
->chan
,
281 wiphy_warn(local
->hw
.wiphy
,
282 "failed to start next HW ROC (%d)\n", ret
);
284 * queue the work struct again to avoid recursion
285 * when multiple failures occur
287 ieee80211_remain_on_channel_expired(&local
->hw
);
291 ieee80211_queue_delayed_work(&local
->hw
, &roc
->work
,
292 round_jiffies_relative(HZ
/2));
296 void ieee80211_roc_notify_destroy(struct ieee80211_roc_work
*roc
)
298 struct ieee80211_roc_work
*dep
, *tmp
;
300 /* was never transmitted */
302 cfg80211_mgmt_tx_status(&roc
->sdata
->wdev
,
303 (unsigned long)roc
->frame
,
304 roc
->frame
->data
, roc
->frame
->len
,
306 kfree_skb(roc
->frame
);
309 if (!roc
->mgmt_tx_cookie
)
310 cfg80211_remain_on_channel_expired(&roc
->sdata
->wdev
,
312 roc
->chan
, roc
->chan_type
,
315 list_for_each_entry_safe(dep
, tmp
, &roc
->dependents
, list
)
316 ieee80211_roc_notify_destroy(dep
);
321 void ieee80211_sw_roc_work(struct work_struct
*work
)
323 struct ieee80211_roc_work
*roc
=
324 container_of(work
, struct ieee80211_roc_work
, work
.work
);
325 struct ieee80211_sub_if_data
*sdata
= roc
->sdata
;
326 struct ieee80211_local
*local
= sdata
->local
;
329 mutex_lock(&local
->mtx
);
334 if (WARN_ON(list_empty(&local
->roc_list
)))
337 if (WARN_ON(roc
!= list_first_entry(&local
->roc_list
,
338 struct ieee80211_roc_work
,
343 struct ieee80211_roc_work
*dep
;
347 /* switch channel etc */
348 ieee80211_recalc_idle(local
);
350 local
->tmp_channel
= roc
->chan
;
351 local
->tmp_channel_type
= roc
->chan_type
;
352 ieee80211_hw_config(local
, 0);
354 /* tell userspace or send frame */
355 ieee80211_handle_roc_started(roc
);
356 list_for_each_entry(dep
, &roc
->dependents
, list
)
357 ieee80211_handle_roc_started(dep
);
359 /* if it was pure TX, just finish right away */
364 ieee80211_queue_delayed_work(&local
->hw
, &roc
->work
,
365 msecs_to_jiffies(roc
->duration
));
367 /* finish this ROC */
369 list_del(&roc
->list
);
370 started
= roc
->started
;
371 ieee80211_roc_notify_destroy(roc
);
374 drv_flush(local
, false);
376 local
->tmp_channel
= NULL
;
377 ieee80211_hw_config(local
, 0);
379 ieee80211_offchannel_return(local
, true);
382 ieee80211_recalc_idle(local
);
385 ieee80211_start_next_roc(local
);
389 mutex_unlock(&local
->mtx
);
392 static void ieee80211_hw_roc_done(struct work_struct
*work
)
394 struct ieee80211_local
*local
=
395 container_of(work
, struct ieee80211_local
, hw_roc_done
);
396 struct ieee80211_roc_work
*roc
;
398 mutex_lock(&local
->mtx
);
400 if (list_empty(&local
->roc_list
))
403 roc
= list_first_entry(&local
->roc_list
, struct ieee80211_roc_work
,
409 list_del(&roc
->list
);
411 ieee80211_roc_notify_destroy(roc
);
413 /* if there's another roc, start it now */
414 ieee80211_start_next_roc(local
);
417 mutex_unlock(&local
->mtx
);
420 void ieee80211_remain_on_channel_expired(struct ieee80211_hw
*hw
)
422 struct ieee80211_local
*local
= hw_to_local(hw
);
424 trace_api_remain_on_channel_expired(local
);
426 ieee80211_queue_work(hw
, &local
->hw_roc_done
);
428 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired
);
430 void ieee80211_roc_setup(struct ieee80211_local
*local
)
432 INIT_WORK(&local
->hw_roc_start
, ieee80211_hw_roc_start
);
433 INIT_WORK(&local
->hw_roc_done
, ieee80211_hw_roc_done
);
434 INIT_LIST_HEAD(&local
->roc_list
);
437 void ieee80211_roc_purge(struct ieee80211_sub_if_data
*sdata
)
439 struct ieee80211_local
*local
= sdata
->local
;
440 struct ieee80211_roc_work
*roc
, *tmp
;
443 mutex_lock(&local
->mtx
);
444 list_for_each_entry_safe(roc
, tmp
, &local
->roc_list
, list
) {
445 if (roc
->sdata
!= sdata
)
448 if (roc
->started
&& local
->ops
->remain_on_channel
) {
449 /* can race, so ignore return value */
450 drv_cancel_remain_on_channel(local
);
453 list_move_tail(&roc
->list
, &tmp_list
);
457 ieee80211_start_next_roc(local
);
458 mutex_unlock(&local
->mtx
);
460 list_for_each_entry_safe(roc
, tmp
, &tmp_list
, list
) {
461 if (local
->ops
->remain_on_channel
) {
462 list_del(&roc
->list
);
463 ieee80211_roc_notify_destroy(roc
);
465 ieee80211_queue_delayed_work(&local
->hw
, &roc
->work
, 0);
467 /* work will clean up etc */
468 flush_delayed_work(&roc
->work
);
472 WARN_ON_ONCE(!list_empty(&tmp_list
));