~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/net/mac80211/offchannel.c

Version: ~ [ linux-5.4-rc3 ] ~ [ linux-5.3.6 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.79 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.149 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.196 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.196 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.75 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * Off-channel operation helpers
  3  *
  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>
 10  *
 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.
 14  */
 15 #include <linux/export.h>
 16 #include <net/mac80211.h>
 17 #include "ieee80211_i.h"
 18 #include "driver-ops.h"
 19 
 20 /*
 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.
 26  */
 27 static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
 28 {
 29         struct ieee80211_local *local = sdata->local;
 30         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 31 
 32         local->offchannel_ps_enabled = false;
 33 
 34         /* FIXME: what to do when local->pspolling is true? */
 35 
 36         del_timer_sync(&local->dynamic_ps_timer);
 37         del_timer_sync(&ifmgd->bcn_mon_timer);
 38         del_timer_sync(&ifmgd->conn_mon_timer);
 39 
 40         cancel_work_sync(&local->dynamic_ps_enable_work);
 41 
 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);
 46         }
 47 
 48         if (!local->offchannel_ps_enabled ||
 49             !ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
 50                 /*
 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
 58                  * are again sleeping.
 59                  */
 60                 ieee80211_send_nullfunc(local, sdata, 1);
 61 }
 62 
 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)
 65 {
 66         struct ieee80211_local *local = sdata->local;
 67 
 68         if (!local->ps_sdata)
 69                 ieee80211_send_nullfunc(local, sdata, 0);
 70         else if (local->offchannel_ps_enabled) {
 71                 /*
 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.
 78                  *
 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
 82                  * hardware.
 83                  */
 84                 /* TODO:  Only set hardware if CONF_PS changed?
 85                  * TODO:  Should we set offchannel_ps_enabled to false?
 86                  */
 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) {
 90                 /*
 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.
 95                  */
 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));
 99         }
100 
101         ieee80211_sta_reset_beacon_monitor(sdata);
102         ieee80211_sta_reset_conn_monitor(sdata);
103 }
104 
105 void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
106 {
107         struct ieee80211_sub_if_data *sdata;
108 
109         if (WARN_ON(local->use_chanctx))
110                 return;
111 
112         /*
113          * notify the AP about us leaving the channel and stop all
114          * STA interfaces.
115          */
116 
117         /*
118          * Stop queues and transmit all frames queued by the driver
119          * before sending nullfunc to enable powersave at the AP.
120          */
121         ieee80211_stop_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
122                                         IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
123                                         false);
124         ieee80211_flush_queues(local, NULL, false);
125 
126         mutex_lock(&local->iflist_mtx);
127         list_for_each_entry(sdata, &local->interfaces, list) {
128                 if (!ieee80211_sdata_running(sdata))
129                         continue;
130 
131                 if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
132                         continue;
133 
134                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
135                         set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
136 
137                 /* Check to see if we should disable beaconing. */
138                 if (sdata->vif.bss_conf.enable_beacon) {
139                         set_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
140                                 &sdata->state);
141                         sdata->vif.bss_conf.enable_beacon = false;
142                         ieee80211_bss_info_change_notify(
143                                 sdata, BSS_CHANGED_BEACON_ENABLED);
144                 }
145 
146                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
147                     sdata->u.mgd.associated)
148                         ieee80211_offchannel_ps_enable(sdata);
149         }
150         mutex_unlock(&local->iflist_mtx);
151 }
152 
153 void ieee80211_offchannel_return(struct ieee80211_local *local)
154 {
155         struct ieee80211_sub_if_data *sdata;
156 
157         if (WARN_ON(local->use_chanctx))
158                 return;
159 
160         mutex_lock(&local->iflist_mtx);
161         list_for_each_entry(sdata, &local->interfaces, list) {
162                 if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
163                         continue;
164 
165                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
166                         clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
167 
168                 if (!ieee80211_sdata_running(sdata))
169                         continue;
170 
171                 /* Tell AP we're back */
172                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
173                     sdata->u.mgd.associated)
174                         ieee80211_offchannel_ps_disable(sdata);
175 
176                 if (test_and_clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
177                                        &sdata->state)) {
178                         sdata->vif.bss_conf.enable_beacon = true;
179                         ieee80211_bss_info_change_notify(
180                                 sdata, BSS_CHANGED_BEACON_ENABLED);
181                 }
182         }
183         mutex_unlock(&local->iflist_mtx);
184 
185         ieee80211_wake_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
186                                         IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
187                                         false);
188 }
189 
190 void ieee80211_handle_roc_started(struct ieee80211_roc_work *roc)
191 {
192         if (roc->notified)
193                 return;
194 
195         if (roc->mgmt_tx_cookie) {
196                 if (!WARN_ON(!roc->frame)) {
197                         ieee80211_tx_skb_tid_band(roc->sdata, roc->frame, 7,
198                                                   roc->chan->band);
199                         roc->frame = NULL;
200                 }
201         } else {
202                 cfg80211_ready_on_channel(&roc->sdata->wdev, roc->cookie,
203                                           roc->chan, roc->req_duration,
204                                           GFP_KERNEL);
205         }
206 
207         roc->notified = true;
208 }
209 
210 static void ieee80211_hw_roc_start(struct work_struct *work)
211 {
212         struct ieee80211_local *local =
213                 container_of(work, struct ieee80211_local, hw_roc_start);
214         struct ieee80211_roc_work *roc, *dep, *tmp;
215 
216         mutex_lock(&local->mtx);
217 
218         if (list_empty(&local->roc_list))
219                 goto out_unlock;
220 
221         roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
222                                list);
223 
224         if (!roc->started)
225                 goto out_unlock;
226 
227         roc->hw_begun = true;
228         roc->hw_start_time = local->hw_roc_start_time;
229 
230         ieee80211_handle_roc_started(roc);
231         list_for_each_entry_safe(dep, tmp, &roc->dependents, list) {
232                 ieee80211_handle_roc_started(dep);
233 
234                 if (dep->duration > roc->duration) {
235                         u32 dur = dep->duration;
236                         dep->duration = dur - roc->duration;
237                         roc->duration = dur;
238                         list_move(&dep->list, &roc->list);
239                 }
240         }
241  out_unlock:
242         mutex_unlock(&local->mtx);
243 }
244 
245 void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
246 {
247         struct ieee80211_local *local = hw_to_local(hw);
248 
249         local->hw_roc_start_time = jiffies;
250 
251         trace_api_ready_on_channel(local);
252 
253         ieee80211_queue_work(hw, &local->hw_roc_start);
254 }
255 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
256 
257 void ieee80211_start_next_roc(struct ieee80211_local *local)
258 {
259         struct ieee80211_roc_work *roc;
260 
261         lockdep_assert_held(&local->mtx);
262 
263         if (list_empty(&local->roc_list)) {
264                 ieee80211_run_deferred_scan(local);
265                 return;
266         }
267 
268         roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
269                                list);
270 
271         if (WARN_ON_ONCE(roc->started))
272                 return;
273 
274         if (local->ops->remain_on_channel) {
275                 int ret, duration = roc->duration;
276 
277                 /* XXX: duplicated, see ieee80211_start_roc_work() */
278                 if (!duration)
279                         duration = 10;
280 
281                 ret = drv_remain_on_channel(local, roc->sdata, roc->chan,
282                                             duration, roc->type);
283 
284                 roc->started = true;
285 
286                 if (ret) {
287                         wiphy_warn(local->hw.wiphy,
288                                    "failed to start next HW ROC (%d)\n", ret);
289                         /*
290                          * queue the work struct again to avoid recursion
291                          * when multiple failures occur
292                          */
293                         ieee80211_remain_on_channel_expired(&local->hw);
294                 }
295         } else {
296                 /* delay it a bit */
297                 ieee80211_queue_delayed_work(&local->hw, &roc->work,
298                                              round_jiffies_relative(HZ/2));
299         }
300 }
301 
302 void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc, bool free)
303 {
304         struct ieee80211_roc_work *dep, *tmp;
305 
306         if (WARN_ON(roc->to_be_freed))
307                 return;
308 
309         /* was never transmitted */
310         if (roc->frame) {
311                 cfg80211_mgmt_tx_status(&roc->sdata->wdev,
312                                         (unsigned long)roc->frame,
313                                         roc->frame->data, roc->frame->len,
314                                         false, GFP_KERNEL);
315                 kfree_skb(roc->frame);
316         }
317 
318         if (!roc->mgmt_tx_cookie)
319                 cfg80211_remain_on_channel_expired(&roc->sdata->wdev,
320                                                    roc->cookie, roc->chan,
321                                                    GFP_KERNEL);
322 
323         list_for_each_entry_safe(dep, tmp, &roc->dependents, list)
324                 ieee80211_roc_notify_destroy(dep, true);
325 
326         if (free)
327                 kfree(roc);
328         else
329                 roc->to_be_freed = true;
330 }
331 
332 void ieee80211_sw_roc_work(struct work_struct *work)
333 {
334         struct ieee80211_roc_work *roc =
335                 container_of(work, struct ieee80211_roc_work, work.work);
336         struct ieee80211_sub_if_data *sdata = roc->sdata;
337         struct ieee80211_local *local = sdata->local;
338         bool started, on_channel;
339 
340         mutex_lock(&local->mtx);
341 
342         if (roc->to_be_freed)
343                 goto out_unlock;
344 
345         if (roc->abort)
346                 goto finish;
347 
348         if (WARN_ON(list_empty(&local->roc_list)))
349                 goto out_unlock;
350 
351         if (WARN_ON(roc != list_first_entry(&local->roc_list,
352                                             struct ieee80211_roc_work,
353                                             list)))
354                 goto out_unlock;
355 
356         if (!roc->started) {
357                 struct ieee80211_roc_work *dep;
358 
359                 WARN_ON(local->use_chanctx);
360 
361                 /* If actually operating on the desired channel (with at least
362                  * 20 MHz channel width) don't stop all the operations but still
363                  * treat it as though the ROC operation started properly, so
364                  * other ROC operations won't interfere with this one.
365                  */
366                 roc->on_channel = roc->chan == local->_oper_chandef.chan &&
367                                   local->_oper_chandef.width != NL80211_CHAN_WIDTH_5 &&
368                                   local->_oper_chandef.width != NL80211_CHAN_WIDTH_10;
369 
370                 /* start this ROC */
371                 ieee80211_recalc_idle(local);
372 
373                 if (!roc->on_channel) {
374                         ieee80211_offchannel_stop_vifs(local);
375 
376                         local->tmp_channel = roc->chan;
377                         ieee80211_hw_config(local, 0);
378                 }
379 
380                 /* tell userspace or send frame */
381                 ieee80211_handle_roc_started(roc);
382                 list_for_each_entry(dep, &roc->dependents, list)
383                         ieee80211_handle_roc_started(dep);
384 
385                 /* if it was pure TX, just finish right away */
386                 if (!roc->duration)
387                         goto finish;
388 
389                 roc->started = true;
390                 ieee80211_queue_delayed_work(&local->hw, &roc->work,
391                                              msecs_to_jiffies(roc->duration));
392         } else {
393                 /* finish this ROC */
394  finish:
395                 list_del(&roc->list);
396                 started = roc->started;
397                 on_channel = roc->on_channel;
398                 ieee80211_roc_notify_destroy(roc, !roc->abort);
399 
400                 if (started && !on_channel) {
401                         ieee80211_flush_queues(local, NULL, false);
402 
403                         local->tmp_channel = NULL;
404                         ieee80211_hw_config(local, 0);
405 
406                         ieee80211_offchannel_return(local);
407                 }
408 
409                 ieee80211_recalc_idle(local);
410 
411                 if (started)
412                         ieee80211_start_next_roc(local);
413                 else if (list_empty(&local->roc_list))
414                         ieee80211_run_deferred_scan(local);
415         }
416 
417  out_unlock:
418         mutex_unlock(&local->mtx);
419 }
420 
421 static void ieee80211_hw_roc_done(struct work_struct *work)
422 {
423         struct ieee80211_local *local =
424                 container_of(work, struct ieee80211_local, hw_roc_done);
425         struct ieee80211_roc_work *roc;
426 
427         mutex_lock(&local->mtx);
428 
429         if (list_empty(&local->roc_list))
430                 goto out_unlock;
431 
432         roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
433                                list);
434 
435         if (!roc->started)
436                 goto out_unlock;
437 
438         list_del(&roc->list);
439 
440         ieee80211_roc_notify_destroy(roc, true);
441 
442         /* if there's another roc, start it now */
443         ieee80211_start_next_roc(local);
444 
445  out_unlock:
446         mutex_unlock(&local->mtx);
447 }
448 
449 void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw)
450 {
451         struct ieee80211_local *local = hw_to_local(hw);
452 
453         trace_api_remain_on_channel_expired(local);
454 
455         ieee80211_queue_work(hw, &local->hw_roc_done);
456 }
457 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired);
458 
459 void ieee80211_roc_setup(struct ieee80211_local *local)
460 {
461         INIT_WORK(&local->hw_roc_start, ieee80211_hw_roc_start);
462         INIT_WORK(&local->hw_roc_done, ieee80211_hw_roc_done);
463         INIT_LIST_HEAD(&local->roc_list);
464 }
465 
466 void ieee80211_roc_purge(struct ieee80211_local *local,
467                          struct ieee80211_sub_if_data *sdata)
468 {
469         struct ieee80211_roc_work *roc, *tmp;
470         LIST_HEAD(tmp_list);
471 
472         mutex_lock(&local->mtx);
473         list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
474                 if (sdata && roc->sdata != sdata)
475                         continue;
476 
477                 if (roc->started && local->ops->remain_on_channel) {
478                         /* can race, so ignore return value */
479                         drv_cancel_remain_on_channel(local);
480                 }
481 
482                 list_move_tail(&roc->list, &tmp_list);
483                 roc->abort = true;
484         }
485         mutex_unlock(&local->mtx);
486 
487         list_for_each_entry_safe(roc, tmp, &tmp_list, list) {
488                 if (local->ops->remain_on_channel) {
489                         list_del(&roc->list);
490                         ieee80211_roc_notify_destroy(roc, true);
491                 } else {
492                         ieee80211_queue_delayed_work(&local->hw, &roc->work, 0);
493 
494                         /* work will clean up etc */
495                         flush_delayed_work(&roc->work);
496                         WARN_ON(!roc->to_be_freed);
497                         kfree(roc);
498                 }
499         }
500 
501         WARN_ON_ONCE(!list_empty(&tmp_list));
502 }
503 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp