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_P2P_DEVICE
)
122 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
)
123 set_bit(SDATA_STATE_OFFCHANNEL
, &sdata
->state
);
125 /* Check to see if we should disable beaconing. */
126 if (sdata
->vif
.type
== NL80211_IFTYPE_AP
||
127 sdata
->vif
.type
== NL80211_IFTYPE_ADHOC
||
128 sdata
->vif
.type
== NL80211_IFTYPE_MESH_POINT
)
129 ieee80211_bss_info_change_notify(
130 sdata
, BSS_CHANGED_BEACON_ENABLED
);
132 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
) {
133 netif_tx_stop_all_queues(sdata
->dev
);
134 if (offchannel_ps_enable
&&
135 (sdata
->vif
.type
== NL80211_IFTYPE_STATION
) &&
136 sdata
->u
.mgd
.associated
)
137 ieee80211_offchannel_ps_enable(sdata
);
140 mutex_unlock(&local
->iflist_mtx
);
143 void ieee80211_offchannel_return(struct ieee80211_local
*local
,
144 bool offchannel_ps_disable
)
146 struct ieee80211_sub_if_data
*sdata
;
148 mutex_lock(&local
->iflist_mtx
);
149 list_for_each_entry(sdata
, &local
->interfaces
, list
) {
150 if (sdata
->vif
.type
== NL80211_IFTYPE_P2P_DEVICE
)
153 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
)
154 clear_bit(SDATA_STATE_OFFCHANNEL
, &sdata
->state
);
156 if (!ieee80211_sdata_running(sdata
))
159 /* Tell AP we're back */
160 if (offchannel_ps_disable
&&
161 sdata
->vif
.type
== NL80211_IFTYPE_STATION
) {
162 if (sdata
->u
.mgd
.associated
)
163 ieee80211_offchannel_ps_disable(sdata
);
166 if (sdata
->vif
.type
!= NL80211_IFTYPE_MONITOR
) {
168 * This may wake up queues even though the driver
169 * currently has them stopped. This is not very
170 * likely, since the driver won't have gotten any
171 * (or hardly any) new packets while we weren't
172 * on the right channel, and even if it happens
173 * it will at most lead to queueing up one more
174 * packet per queue in mac80211 rather than on
175 * the interface qdisc.
177 netif_tx_wake_all_queues(sdata
->dev
);
180 if (sdata
->vif
.type
== NL80211_IFTYPE_AP
||
181 sdata
->vif
.type
== NL80211_IFTYPE_ADHOC
||
182 sdata
->vif
.type
== NL80211_IFTYPE_MESH_POINT
)
183 ieee80211_bss_info_change_notify(
184 sdata
, BSS_CHANGED_BEACON_ENABLED
);
186 mutex_unlock(&local
->iflist_mtx
);
189 void ieee80211_handle_roc_started(struct ieee80211_roc_work
*roc
)
194 if (roc
->mgmt_tx_cookie
) {
195 if (!WARN_ON(!roc
->frame
)) {
196 ieee80211_tx_skb(roc
->sdata
, roc
->frame
);
200 cfg80211_ready_on_channel(&roc
->sdata
->wdev
, (unsigned long)roc
,
201 roc
->chan
, roc
->chan_type
,
202 roc
->req_duration
, GFP_KERNEL
);
205 roc
->notified
= true;
208 static void ieee80211_hw_roc_start(struct work_struct
*work
)
210 struct ieee80211_local
*local
=
211 container_of(work
, struct ieee80211_local
, hw_roc_start
);
212 struct ieee80211_roc_work
*roc
, *dep
, *tmp
;
214 mutex_lock(&local
->mtx
);
216 if (list_empty(&local
->roc_list
))
219 roc
= list_first_entry(&local
->roc_list
, struct ieee80211_roc_work
,
225 roc
->hw_begun
= true;
226 roc
->hw_start_time
= local
->hw_roc_start_time
;
228 ieee80211_handle_roc_started(roc
);
229 list_for_each_entry_safe(dep
, tmp
, &roc
->dependents
, list
) {
230 ieee80211_handle_roc_started(dep
);
232 if (dep
->duration
> roc
->duration
) {
233 u32 dur
= dep
->duration
;
234 dep
->duration
= dur
- roc
->duration
;
236 list_move(&dep
->list
, &roc
->list
);
240 mutex_unlock(&local
->mtx
);
243 void ieee80211_ready_on_channel(struct ieee80211_hw
*hw
)
245 struct ieee80211_local
*local
= hw_to_local(hw
);
247 local
->hw_roc_start_time
= jiffies
;
249 trace_api_ready_on_channel(local
);
251 ieee80211_queue_work(hw
, &local
->hw_roc_start
);
253 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel
);
255 void ieee80211_start_next_roc(struct ieee80211_local
*local
)
257 struct ieee80211_roc_work
*roc
;
259 lockdep_assert_held(&local
->mtx
);
261 if (list_empty(&local
->roc_list
)) {
262 ieee80211_run_deferred_scan(local
);
266 roc
= list_first_entry(&local
->roc_list
, struct ieee80211_roc_work
,
269 if (WARN_ON_ONCE(roc
->started
))
272 if (local
->ops
->remain_on_channel
) {
273 int ret
, duration
= roc
->duration
;
275 /* XXX: duplicated, see ieee80211_start_roc_work() */
279 ret
= drv_remain_on_channel(local
, roc
->chan
,
286 wiphy_warn(local
->hw
.wiphy
,
287 "failed to start next HW ROC (%d)\n", ret
);
289 * queue the work struct again to avoid recursion
290 * when multiple failures occur
292 ieee80211_remain_on_channel_expired(&local
->hw
);
296 ieee80211_queue_delayed_work(&local
->hw
, &roc
->work
,
297 round_jiffies_relative(HZ
/2));
301 void ieee80211_roc_notify_destroy(struct ieee80211_roc_work
*roc
)
303 struct ieee80211_roc_work
*dep
, *tmp
;
305 /* was never transmitted */
307 cfg80211_mgmt_tx_status(&roc
->sdata
->wdev
,
308 (unsigned long)roc
->frame
,
309 roc
->frame
->data
, roc
->frame
->len
,
311 kfree_skb(roc
->frame
);
314 if (!roc
->mgmt_tx_cookie
)
315 cfg80211_remain_on_channel_expired(&roc
->sdata
->wdev
,
317 roc
->chan
, roc
->chan_type
,
320 list_for_each_entry_safe(dep
, tmp
, &roc
->dependents
, list
)
321 ieee80211_roc_notify_destroy(dep
);
326 void ieee80211_sw_roc_work(struct work_struct
*work
)
328 struct ieee80211_roc_work
*roc
=
329 container_of(work
, struct ieee80211_roc_work
, work
.work
);
330 struct ieee80211_sub_if_data
*sdata
= roc
->sdata
;
331 struct ieee80211_local
*local
= sdata
->local
;
334 mutex_lock(&local
->mtx
);
339 if (WARN_ON(list_empty(&local
->roc_list
)))
342 if (WARN_ON(roc
!= list_first_entry(&local
->roc_list
,
343 struct ieee80211_roc_work
,
348 struct ieee80211_roc_work
*dep
;
352 /* switch channel etc */
353 ieee80211_recalc_idle(local
);
355 local
->tmp_channel
= roc
->chan
;
356 local
->tmp_channel_type
= roc
->chan_type
;
357 ieee80211_hw_config(local
, 0);
359 /* tell userspace or send frame */
360 ieee80211_handle_roc_started(roc
);
361 list_for_each_entry(dep
, &roc
->dependents
, list
)
362 ieee80211_handle_roc_started(dep
);
364 /* if it was pure TX, just finish right away */
369 ieee80211_queue_delayed_work(&local
->hw
, &roc
->work
,
370 msecs_to_jiffies(roc
->duration
));
372 /* finish this ROC */
374 list_del(&roc
->list
);
375 started
= roc
->started
;
376 ieee80211_roc_notify_destroy(roc
);
379 drv_flush(local
, false);
381 local
->tmp_channel
= NULL
;
382 ieee80211_hw_config(local
, 0);
384 ieee80211_offchannel_return(local
, true);
387 ieee80211_recalc_idle(local
);
390 ieee80211_start_next_roc(local
);
394 mutex_unlock(&local
->mtx
);
397 static void ieee80211_hw_roc_done(struct work_struct
*work
)
399 struct ieee80211_local
*local
=
400 container_of(work
, struct ieee80211_local
, hw_roc_done
);
401 struct ieee80211_roc_work
*roc
;
403 mutex_lock(&local
->mtx
);
405 if (list_empty(&local
->roc_list
))
408 roc
= list_first_entry(&local
->roc_list
, struct ieee80211_roc_work
,
414 list_del(&roc
->list
);
416 ieee80211_roc_notify_destroy(roc
);
418 /* if there's another roc, start it now */
419 ieee80211_start_next_roc(local
);
422 mutex_unlock(&local
->mtx
);
425 void ieee80211_remain_on_channel_expired(struct ieee80211_hw
*hw
)
427 struct ieee80211_local
*local
= hw_to_local(hw
);
429 trace_api_remain_on_channel_expired(local
);
431 ieee80211_queue_work(hw
, &local
->hw_roc_done
);
433 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired
);
435 void ieee80211_roc_setup(struct ieee80211_local
*local
)
437 INIT_WORK(&local
->hw_roc_start
, ieee80211_hw_roc_start
);
438 INIT_WORK(&local
->hw_roc_done
, ieee80211_hw_roc_done
);
439 INIT_LIST_HEAD(&local
->roc_list
);
442 void ieee80211_roc_purge(struct ieee80211_sub_if_data
*sdata
)
444 struct ieee80211_local
*local
= sdata
->local
;
445 struct ieee80211_roc_work
*roc
, *tmp
;
448 mutex_lock(&local
->mtx
);
449 list_for_each_entry_safe(roc
, tmp
, &local
->roc_list
, list
) {
450 if (roc
->sdata
!= sdata
)
453 if (roc
->started
&& local
->ops
->remain_on_channel
) {
454 /* can race, so ignore return value */
455 drv_cancel_remain_on_channel(local
);
458 list_move_tail(&roc
->list
, &tmp_list
);
462 ieee80211_start_next_roc(local
);
463 mutex_unlock(&local
->mtx
);
465 list_for_each_entry_safe(roc
, tmp
, &tmp_list
, list
) {
466 if (local
->ops
->remain_on_channel
) {
467 list_del(&roc
->list
);
468 ieee80211_roc_notify_destroy(roc
);
470 ieee80211_queue_delayed_work(&local
->hw
, &roc
->work
, 0);
472 /* work will clean up etc */
473 flush_delayed_work(&roc
->work
);
477 WARN_ON_ONCE(!list_empty(&tmp_list
));