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;
110 if (WARN_ON(local->use_chanctx))
114 * notify the AP about us leaving the channel and stop all
117 mutex_lock(&local->iflist_mtx);
118 list_for_each_entry(sdata, &local->interfaces, list) {
119 if (!ieee80211_sdata_running(sdata))
122 if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
125 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
126 set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
128 /* Check to see if we should disable beaconing. */
129 if (sdata->vif.bss_conf.enable_beacon) {
130 set_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
132 sdata->vif.bss_conf.enable_beacon = false;
133 ieee80211_bss_info_change_notify(
134 sdata, BSS_CHANGED_BEACON_ENABLED);
137 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
138 netif_tx_stop_all_queues(sdata->dev);
139 if (offchannel_ps_enable &&
140 (sdata->vif.type == NL80211_IFTYPE_STATION) &&
141 sdata->u.mgd.associated)
142 ieee80211_offchannel_ps_enable(sdata);
145 mutex_unlock(&local->iflist_mtx);
148 void ieee80211_offchannel_return(struct ieee80211_local *local,
149 bool offchannel_ps_disable)
151 struct ieee80211_sub_if_data *sdata;
153 if (WARN_ON(local->use_chanctx))
156 mutex_lock(&local->iflist_mtx);
157 list_for_each_entry(sdata, &local->interfaces, list) {
158 if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
161 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
162 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
164 if (!ieee80211_sdata_running(sdata))
167 /* Tell AP we're back */
168 if (offchannel_ps_disable &&
169 sdata->vif.type == NL80211_IFTYPE_STATION) {
170 if (sdata->u.mgd.associated)
171 ieee80211_offchannel_ps_disable(sdata);
174 if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
176 * This may wake up queues even though the driver
177 * currently has them stopped. This is not very
178 * likely, since the driver won't have gotten any
179 * (or hardly any) new packets while we weren't
180 * on the right channel, and even if it happens
181 * it will at most lead to queueing up one more
182 * packet per queue in mac80211 rather than on
183 * the interface qdisc.
185 netif_tx_wake_all_queues(sdata->dev);
188 if (test_and_clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
190 sdata->vif.bss_conf.enable_beacon = true;
191 ieee80211_bss_info_change_notify(
192 sdata, BSS_CHANGED_BEACON_ENABLED);
195 mutex_unlock(&local->iflist_mtx);
198 void ieee80211_handle_roc_started(struct ieee80211_roc_work *roc)
203 if (roc->mgmt_tx_cookie) {
204 if (!WARN_ON(!roc->frame)) {
205 ieee80211_tx_skb_tid_band(roc->sdata, roc->frame, 7,
210 cfg80211_ready_on_channel(&roc->sdata->wdev, roc->cookie,
211 roc->chan, roc->req_duration,
215 roc->notified = true;
218 static void ieee80211_hw_roc_start(struct work_struct *work)
220 struct ieee80211_local *local =
221 container_of(work, struct ieee80211_local, hw_roc_start);
222 struct ieee80211_roc_work *roc, *dep, *tmp;
224 mutex_lock(&local->mtx);
226 if (list_empty(&local->roc_list))
229 roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
235 roc->hw_begun = true;
236 roc->hw_start_time = local->hw_roc_start_time;
238 ieee80211_handle_roc_started(roc);
239 list_for_each_entry_safe(dep, tmp, &roc->dependents, list) {
240 ieee80211_handle_roc_started(dep);
242 if (dep->duration > roc->duration) {
243 u32 dur = dep->duration;
244 dep->duration = dur - roc->duration;
246 list_move(&dep->list, &roc->list);
250 mutex_unlock(&local->mtx);
253 void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
255 struct ieee80211_local *local = hw_to_local(hw);
257 local->hw_roc_start_time = jiffies;
259 trace_api_ready_on_channel(local);
261 ieee80211_queue_work(hw, &local->hw_roc_start);
263 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
265 void ieee80211_start_next_roc(struct ieee80211_local *local)
267 struct ieee80211_roc_work *roc;
269 lockdep_assert_held(&local->mtx);
271 if (list_empty(&local->roc_list)) {
272 ieee80211_run_deferred_scan(local);
276 roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
279 if (WARN_ON_ONCE(roc->started))
282 if (local->ops->remain_on_channel) {
283 int ret, duration = roc->duration;
285 /* XXX: duplicated, see ieee80211_start_roc_work() */
289 ret = drv_remain_on_channel(local, roc->sdata, roc->chan,
295 wiphy_warn(local->hw.wiphy,
296 "failed to start next HW ROC (%d)\n", ret);
298 * queue the work struct again to avoid recursion
299 * when multiple failures occur
301 ieee80211_remain_on_channel_expired(&local->hw);
305 ieee80211_queue_delayed_work(&local->hw, &roc->work,
306 round_jiffies_relative(HZ/2));
310 void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc)
312 struct ieee80211_roc_work *dep, *tmp;
314 /* was never transmitted */
316 cfg80211_mgmt_tx_status(&roc->sdata->wdev,
317 (unsigned long)roc->frame,
318 roc->frame->data, roc->frame->len,
320 kfree_skb(roc->frame);
323 if (!roc->mgmt_tx_cookie)
324 cfg80211_remain_on_channel_expired(&roc->sdata->wdev,
325 roc->cookie, roc->chan,
328 list_for_each_entry_safe(dep, tmp, &roc->dependents, list)
329 ieee80211_roc_notify_destroy(dep);
334 void ieee80211_sw_roc_work(struct work_struct *work)
336 struct ieee80211_roc_work *roc =
337 container_of(work, struct ieee80211_roc_work, work.work);
338 struct ieee80211_sub_if_data *sdata = roc->sdata;
339 struct ieee80211_local *local = sdata->local;
342 mutex_lock(&local->mtx);
347 if (WARN_ON(list_empty(&local->roc_list)))
350 if (WARN_ON(roc != list_first_entry(&local->roc_list,
351 struct ieee80211_roc_work,
356 struct ieee80211_roc_work *dep;
360 /* switch channel etc */
361 ieee80211_recalc_idle(local);
363 local->tmp_channel = roc->chan;
364 ieee80211_hw_config(local, 0);
366 /* tell userspace or send frame */
367 ieee80211_handle_roc_started(roc);
368 list_for_each_entry(dep, &roc->dependents, list)
369 ieee80211_handle_roc_started(dep);
371 /* if it was pure TX, just finish right away */
376 ieee80211_queue_delayed_work(&local->hw, &roc->work,
377 msecs_to_jiffies(roc->duration));
379 /* finish this ROC */
381 list_del(&roc->list);
382 started = roc->started;
383 ieee80211_roc_notify_destroy(roc);
386 drv_flush(local, false);
388 local->tmp_channel = NULL;
389 ieee80211_hw_config(local, 0);
391 ieee80211_offchannel_return(local, true);
394 ieee80211_recalc_idle(local);
397 ieee80211_start_next_roc(local);
401 mutex_unlock(&local->mtx);
404 static void ieee80211_hw_roc_done(struct work_struct *work)
406 struct ieee80211_local *local =
407 container_of(work, struct ieee80211_local, hw_roc_done);
408 struct ieee80211_roc_work *roc;
410 mutex_lock(&local->mtx);
412 if (list_empty(&local->roc_list))
415 roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
421 list_del(&roc->list);
423 ieee80211_roc_notify_destroy(roc);
425 /* if there's another roc, start it now */
426 ieee80211_start_next_roc(local);
429 mutex_unlock(&local->mtx);
432 void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw)
434 struct ieee80211_local *local = hw_to_local(hw);
436 trace_api_remain_on_channel_expired(local);
438 ieee80211_queue_work(hw, &local->hw_roc_done);
440 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired);
442 void ieee80211_roc_setup(struct ieee80211_local *local)
444 INIT_WORK(&local->hw_roc_start, ieee80211_hw_roc_start);
445 INIT_WORK(&local->hw_roc_done, ieee80211_hw_roc_done);
446 INIT_LIST_HEAD(&local->roc_list);
449 void ieee80211_roc_purge(struct ieee80211_sub_if_data *sdata)
451 struct ieee80211_local *local = sdata->local;
452 struct ieee80211_roc_work *roc, *tmp;
455 mutex_lock(&local->mtx);
456 list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
457 if (roc->sdata != sdata)
460 if (roc->started && local->ops->remain_on_channel) {
461 /* can race, so ignore return value */
462 drv_cancel_remain_on_channel(local);
465 list_move_tail(&roc->list, &tmp_list);
468 mutex_unlock(&local->mtx);
470 list_for_each_entry_safe(roc, tmp, &tmp_list, list) {
471 if (local->ops->remain_on_channel) {
472 list_del(&roc->list);
473 ieee80211_roc_notify_destroy(roc);
475 ieee80211_queue_delayed_work(&local->hw, &roc->work, 0);
477 /* work will clean up etc */
478 flush_delayed_work(&roc->work);
482 WARN_ON_ONCE(!list_empty(&tmp_list));