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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Off-channel operation helpers
4  *
5  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6  * Copyright 2004, Instant802 Networks, Inc.
7  * Copyright 2005, Devicescape Software, Inc.
8  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
9  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10  * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
11  * Copyright (C) 2019, 2022 Intel Corporation
12  */
13 #include <linux/export.h>
14 #include <net/mac80211.h>
15 #include "ieee80211_i.h"
16 #include "driver-ops.h"
17 
18 /*
19  * Tell our hardware to disable PS.
20  * Optionally inform AP that we will go to sleep so that it will buffer
21  * the frames while we are doing off-channel work.  This is optional
22  * because we *may* be doing work on-operating channel, and want our
23  * hardware unconditionally awake, but still let the AP send us normal frames.
24  */
ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data * sdata)25 static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
26 {
27 	struct ieee80211_local *local = sdata->local;
28 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
29 	bool offchannel_ps_enabled = false;
30 
31 	/* FIXME: what to do when local->pspolling is true? */
32 
33 	del_timer_sync(&local->dynamic_ps_timer);
34 	del_timer_sync(&ifmgd->bcn_mon_timer);
35 	del_timer_sync(&ifmgd->conn_mon_timer);
36 
37 	cancel_work_sync(&local->dynamic_ps_enable_work);
38 
39 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
40 		offchannel_ps_enabled = true;
41 		local->hw.conf.flags &= ~IEEE80211_CONF_PS;
42 		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
43 	}
44 
45 	if (!offchannel_ps_enabled ||
46 	    !ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
47 		/*
48 		 * If power save was enabled, no need to send a nullfunc
49 		 * frame because AP knows that we are sleeping. But if the
50 		 * hardware is creating the nullfunc frame for power save
51 		 * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
52 		 * enabled) and power save was enabled, the firmware just
53 		 * sent a null frame with power save disabled. So we need
54 		 * to send a new nullfunc frame to inform the AP that we
55 		 * are again sleeping.
56 		 */
57 		ieee80211_send_nullfunc(local, sdata, true);
58 }
59 
60 /* inform AP that we are awake again */
ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data * sdata)61 static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
62 {
63 	struct ieee80211_local *local = sdata->local;
64 
65 	if (!local->ps_sdata)
66 		ieee80211_send_nullfunc(local, sdata, false);
67 	else if (local->hw.conf.dynamic_ps_timeout > 0) {
68 		/*
69 		 * the dynamic_ps_timer had been running before leaving the
70 		 * operating channel, restart the timer now and send a nullfunc
71 		 * frame to inform the AP that we are awake so that AP sends
72 		 * the buffered packets (if any).
73 		 */
74 		ieee80211_send_nullfunc(local, sdata, false);
75 		mod_timer(&local->dynamic_ps_timer, jiffies +
76 			  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
77 	}
78 
79 	ieee80211_sta_reset_beacon_monitor(sdata);
80 	ieee80211_sta_reset_conn_monitor(sdata);
81 }
82 
ieee80211_offchannel_stop_vifs(struct ieee80211_local * local)83 void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
84 {
85 	struct ieee80211_sub_if_data *sdata;
86 
87 	if (WARN_ON(local->use_chanctx))
88 		return;
89 
90 	/*
91 	 * notify the AP about us leaving the channel and stop all
92 	 * STA interfaces.
93 	 */
94 
95 	/*
96 	 * Stop queues and transmit all frames queued by the driver
97 	 * before sending nullfunc to enable powersave at the AP.
98 	 */
99 	ieee80211_stop_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
100 					IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
101 					false);
102 	ieee80211_flush_queues(local, NULL, false);
103 
104 	mutex_lock(&local->iflist_mtx);
105 	list_for_each_entry(sdata, &local->interfaces, list) {
106 		if (!ieee80211_sdata_running(sdata))
107 			continue;
108 
109 		if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE ||
110 		    sdata->vif.type == NL80211_IFTYPE_NAN)
111 			continue;
112 
113 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
114 			set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
115 
116 		/* Check to see if we should disable beaconing. */
117 		if (sdata->vif.bss_conf.enable_beacon) {
118 			set_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
119 				&sdata->state);
120 			sdata->vif.bss_conf.enable_beacon = false;
121 			ieee80211_link_info_change_notify(
122 				sdata, &sdata->deflink,
123 				BSS_CHANGED_BEACON_ENABLED);
124 		}
125 
126 		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
127 		    sdata->u.mgd.associated)
128 			ieee80211_offchannel_ps_enable(sdata);
129 	}
130 	mutex_unlock(&local->iflist_mtx);
131 }
132 
ieee80211_offchannel_return(struct ieee80211_local * local)133 void ieee80211_offchannel_return(struct ieee80211_local *local)
134 {
135 	struct ieee80211_sub_if_data *sdata;
136 
137 	if (WARN_ON(local->use_chanctx))
138 		return;
139 
140 	mutex_lock(&local->iflist_mtx);
141 	list_for_each_entry(sdata, &local->interfaces, list) {
142 		if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
143 			continue;
144 
145 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
146 			clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
147 
148 		if (!ieee80211_sdata_running(sdata))
149 			continue;
150 
151 		/* Tell AP we're back */
152 		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
153 		    sdata->u.mgd.associated)
154 			ieee80211_offchannel_ps_disable(sdata);
155 
156 		if (test_and_clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
157 				       &sdata->state)) {
158 			sdata->vif.bss_conf.enable_beacon = true;
159 			ieee80211_link_info_change_notify(
160 				sdata, &sdata->deflink,
161 				BSS_CHANGED_BEACON_ENABLED);
162 		}
163 	}
164 	mutex_unlock(&local->iflist_mtx);
165 
166 	ieee80211_wake_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
167 					IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
168 					false);
169 }
170 
ieee80211_roc_notify_destroy(struct ieee80211_roc_work * roc)171 static void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc)
172 {
173 	/* was never transmitted */
174 	if (roc->frame) {
175 		cfg80211_mgmt_tx_status(&roc->sdata->wdev, roc->mgmt_tx_cookie,
176 					roc->frame->data, roc->frame->len,
177 					false, GFP_KERNEL);
178 		ieee80211_free_txskb(&roc->sdata->local->hw, roc->frame);
179 	}
180 
181 	if (!roc->mgmt_tx_cookie)
182 		cfg80211_remain_on_channel_expired(&roc->sdata->wdev,
183 						   roc->cookie, roc->chan,
184 						   GFP_KERNEL);
185 	else
186 		cfg80211_tx_mgmt_expired(&roc->sdata->wdev,
187 					 roc->mgmt_tx_cookie,
188 					 roc->chan, GFP_KERNEL);
189 
190 	list_del(&roc->list);
191 	kfree(roc);
192 }
193 
ieee80211_end_finished_rocs(struct ieee80211_local * local,unsigned long now)194 static unsigned long ieee80211_end_finished_rocs(struct ieee80211_local *local,
195 						 unsigned long now)
196 {
197 	struct ieee80211_roc_work *roc, *tmp;
198 	long remaining_dur_min = LONG_MAX;
199 
200 	lockdep_assert_held(&local->mtx);
201 
202 	list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
203 		long remaining;
204 
205 		if (!roc->started)
206 			break;
207 
208 		remaining = roc->start_time +
209 			    msecs_to_jiffies(roc->duration) -
210 			    now;
211 
212 		/* In case of HW ROC, it is possible that the HW finished the
213 		 * ROC session before the actual requested time. In such a case
214 		 * end the ROC session (disregarding the remaining time).
215 		 */
216 		if (roc->abort || roc->hw_begun || remaining <= 0)
217 			ieee80211_roc_notify_destroy(roc);
218 		else
219 			remaining_dur_min = min(remaining_dur_min, remaining);
220 	}
221 
222 	return remaining_dur_min;
223 }
224 
ieee80211_recalc_sw_work(struct ieee80211_local * local,unsigned long now)225 static bool ieee80211_recalc_sw_work(struct ieee80211_local *local,
226 				     unsigned long now)
227 {
228 	long dur = ieee80211_end_finished_rocs(local, now);
229 
230 	if (dur == LONG_MAX)
231 		return false;
232 
233 	wiphy_delayed_work_queue(local->hw.wiphy, &local->roc_work, dur);
234 	return true;
235 }
236 
ieee80211_handle_roc_started(struct ieee80211_roc_work * roc,unsigned long start_time)237 static void ieee80211_handle_roc_started(struct ieee80211_roc_work *roc,
238 					 unsigned long start_time)
239 {
240 	if (WARN_ON(roc->notified))
241 		return;
242 
243 	roc->start_time = start_time;
244 	roc->started = true;
245 
246 	if (roc->mgmt_tx_cookie) {
247 		if (!WARN_ON(!roc->frame)) {
248 			ieee80211_tx_skb_tid_band(roc->sdata, roc->frame, 7,
249 						  roc->chan->band);
250 			roc->frame = NULL;
251 		}
252 	} else {
253 		cfg80211_ready_on_channel(&roc->sdata->wdev, roc->cookie,
254 					  roc->chan, roc->req_duration,
255 					  GFP_KERNEL);
256 	}
257 
258 	roc->notified = true;
259 }
260 
ieee80211_hw_roc_start(struct wiphy * wiphy,struct wiphy_work * work)261 static void ieee80211_hw_roc_start(struct wiphy *wiphy, struct wiphy_work *work)
262 {
263 	struct ieee80211_local *local =
264 		container_of(work, struct ieee80211_local, hw_roc_start);
265 	struct ieee80211_roc_work *roc;
266 
267 	mutex_lock(&local->mtx);
268 
269 	list_for_each_entry(roc, &local->roc_list, list) {
270 		if (!roc->started)
271 			break;
272 
273 		roc->hw_begun = true;
274 		ieee80211_handle_roc_started(roc, local->hw_roc_start_time);
275 	}
276 
277 	mutex_unlock(&local->mtx);
278 }
279 
ieee80211_ready_on_channel(struct ieee80211_hw * hw)280 void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
281 {
282 	struct ieee80211_local *local = hw_to_local(hw);
283 
284 	local->hw_roc_start_time = jiffies;
285 
286 	trace_api_ready_on_channel(local);
287 
288 	wiphy_work_queue(hw->wiphy, &local->hw_roc_start);
289 }
290 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
291 
_ieee80211_start_next_roc(struct ieee80211_local * local)292 static void _ieee80211_start_next_roc(struct ieee80211_local *local)
293 {
294 	struct ieee80211_roc_work *roc, *tmp;
295 	enum ieee80211_roc_type type;
296 	u32 min_dur, max_dur;
297 
298 	lockdep_assert_held(&local->mtx);
299 
300 	if (WARN_ON(list_empty(&local->roc_list)))
301 		return;
302 
303 	roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
304 			       list);
305 
306 	if (WARN_ON(roc->started))
307 		return;
308 
309 	min_dur = roc->duration;
310 	max_dur = roc->duration;
311 	type = roc->type;
312 
313 	list_for_each_entry(tmp, &local->roc_list, list) {
314 		if (tmp == roc)
315 			continue;
316 		if (tmp->sdata != roc->sdata || tmp->chan != roc->chan)
317 			break;
318 		max_dur = max(tmp->duration, max_dur);
319 		min_dur = min(tmp->duration, min_dur);
320 		type = max(tmp->type, type);
321 	}
322 
323 	if (local->ops->remain_on_channel) {
324 		int ret = drv_remain_on_channel(local, roc->sdata, roc->chan,
325 						max_dur, type);
326 
327 		if (ret) {
328 			wiphy_warn(local->hw.wiphy,
329 				   "failed to start next HW ROC (%d)\n", ret);
330 			/*
331 			 * queue the work struct again to avoid recursion
332 			 * when multiple failures occur
333 			 */
334 			list_for_each_entry(tmp, &local->roc_list, list) {
335 				if (tmp->sdata != roc->sdata ||
336 				    tmp->chan != roc->chan)
337 					break;
338 				tmp->started = true;
339 				tmp->abort = true;
340 			}
341 			wiphy_work_queue(local->hw.wiphy, &local->hw_roc_done);
342 			return;
343 		}
344 
345 		/* we'll notify about the start once the HW calls back */
346 		list_for_each_entry(tmp, &local->roc_list, list) {
347 			if (tmp->sdata != roc->sdata || tmp->chan != roc->chan)
348 				break;
349 			tmp->started = true;
350 		}
351 	} else {
352 		/* If actually operating on the desired channel (with at least
353 		 * 20 MHz channel width) don't stop all the operations but still
354 		 * treat it as though the ROC operation started properly, so
355 		 * other ROC operations won't interfere with this one.
356 		 */
357 		roc->on_channel = roc->chan == local->_oper_chandef.chan &&
358 				  local->_oper_chandef.width != NL80211_CHAN_WIDTH_5 &&
359 				  local->_oper_chandef.width != NL80211_CHAN_WIDTH_10;
360 
361 		/* start this ROC */
362 		ieee80211_recalc_idle(local);
363 
364 		if (!roc->on_channel) {
365 			ieee80211_offchannel_stop_vifs(local);
366 
367 			local->tmp_channel = roc->chan;
368 			ieee80211_hw_config(local, 0);
369 		}
370 
371 		wiphy_delayed_work_queue(local->hw.wiphy, &local->roc_work,
372 					 msecs_to_jiffies(min_dur));
373 
374 		/* tell userspace or send frame(s) */
375 		list_for_each_entry(tmp, &local->roc_list, list) {
376 			if (tmp->sdata != roc->sdata || tmp->chan != roc->chan)
377 				break;
378 
379 			tmp->on_channel = roc->on_channel;
380 			ieee80211_handle_roc_started(tmp, jiffies);
381 		}
382 	}
383 }
384 
ieee80211_start_next_roc(struct ieee80211_local * local)385 void ieee80211_start_next_roc(struct ieee80211_local *local)
386 {
387 	struct ieee80211_roc_work *roc;
388 
389 	lockdep_assert_held(&local->mtx);
390 
391 	if (list_empty(&local->roc_list)) {
392 		ieee80211_run_deferred_scan(local);
393 		return;
394 	}
395 
396 	/* defer roc if driver is not started (i.e. during reconfig) */
397 	if (local->in_reconfig)
398 		return;
399 
400 	roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
401 			       list);
402 
403 	if (WARN_ON_ONCE(roc->started))
404 		return;
405 
406 	if (local->ops->remain_on_channel) {
407 		_ieee80211_start_next_roc(local);
408 	} else {
409 		/* delay it a bit */
410 		wiphy_delayed_work_queue(local->hw.wiphy, &local->roc_work,
411 					 round_jiffies_relative(HZ / 2));
412 	}
413 }
414 
__ieee80211_roc_work(struct ieee80211_local * local)415 static void __ieee80211_roc_work(struct ieee80211_local *local)
416 {
417 	struct ieee80211_roc_work *roc;
418 	bool on_channel;
419 
420 	lockdep_assert_held(&local->mtx);
421 
422 	if (WARN_ON(local->ops->remain_on_channel))
423 		return;
424 
425 	roc = list_first_entry_or_null(&local->roc_list,
426 				       struct ieee80211_roc_work, list);
427 	if (!roc)
428 		return;
429 
430 	if (!roc->started) {
431 		WARN_ON(local->use_chanctx);
432 		_ieee80211_start_next_roc(local);
433 	} else {
434 		on_channel = roc->on_channel;
435 		if (ieee80211_recalc_sw_work(local, jiffies))
436 			return;
437 
438 		/* careful - roc pointer became invalid during recalc */
439 
440 		if (!on_channel) {
441 			ieee80211_flush_queues(local, NULL, false);
442 
443 			local->tmp_channel = NULL;
444 			ieee80211_hw_config(local, 0);
445 
446 			ieee80211_offchannel_return(local);
447 		}
448 
449 		ieee80211_recalc_idle(local);
450 		ieee80211_start_next_roc(local);
451 	}
452 }
453 
ieee80211_roc_work(struct wiphy * wiphy,struct wiphy_work * work)454 static void ieee80211_roc_work(struct wiphy *wiphy, struct wiphy_work *work)
455 {
456 	struct ieee80211_local *local =
457 		container_of(work, struct ieee80211_local, roc_work.work);
458 
459 	mutex_lock(&local->mtx);
460 	__ieee80211_roc_work(local);
461 	mutex_unlock(&local->mtx);
462 }
463 
ieee80211_hw_roc_done(struct wiphy * wiphy,struct wiphy_work * work)464 static void ieee80211_hw_roc_done(struct wiphy *wiphy, struct wiphy_work *work)
465 {
466 	struct ieee80211_local *local =
467 		container_of(work, struct ieee80211_local, hw_roc_done);
468 
469 	mutex_lock(&local->mtx);
470 
471 	ieee80211_end_finished_rocs(local, jiffies);
472 
473 	/* if there's another roc, start it now */
474 	ieee80211_start_next_roc(local);
475 
476 	mutex_unlock(&local->mtx);
477 }
478 
ieee80211_remain_on_channel_expired(struct ieee80211_hw * hw)479 void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw)
480 {
481 	struct ieee80211_local *local = hw_to_local(hw);
482 
483 	trace_api_remain_on_channel_expired(local);
484 
485 	wiphy_work_queue(hw->wiphy, &local->hw_roc_done);
486 }
487 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired);
488 
489 static bool
ieee80211_coalesce_hw_started_roc(struct ieee80211_local * local,struct ieee80211_roc_work * new_roc,struct ieee80211_roc_work * cur_roc)490 ieee80211_coalesce_hw_started_roc(struct ieee80211_local *local,
491 				  struct ieee80211_roc_work *new_roc,
492 				  struct ieee80211_roc_work *cur_roc)
493 {
494 	unsigned long now = jiffies;
495 	unsigned long remaining;
496 
497 	if (WARN_ON(!cur_roc->started))
498 		return false;
499 
500 	/* if it was scheduled in the hardware, but not started yet,
501 	 * we can only combine if the older one had a longer duration
502 	 */
503 	if (!cur_roc->hw_begun && new_roc->duration > cur_roc->duration)
504 		return false;
505 
506 	remaining = cur_roc->start_time +
507 		    msecs_to_jiffies(cur_roc->duration) -
508 		    now;
509 
510 	/* if it doesn't fit entirely, schedule a new one */
511 	if (new_roc->duration > jiffies_to_msecs(remaining))
512 		return false;
513 
514 	/* add just after the current one so we combine their finish later */
515 	list_add(&new_roc->list, &cur_roc->list);
516 
517 	/* if the existing one has already begun then let this one also
518 	 * begin, otherwise they'll both be marked properly by the work
519 	 * struct that runs once the driver notifies us of the beginning
520 	 */
521 	if (cur_roc->hw_begun) {
522 		new_roc->hw_begun = true;
523 		ieee80211_handle_roc_started(new_roc, now);
524 	}
525 
526 	return true;
527 }
528 
ieee80211_start_roc_work(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata,struct ieee80211_channel * channel,unsigned int duration,u64 * cookie,struct sk_buff * txskb,enum ieee80211_roc_type type)529 static int ieee80211_start_roc_work(struct ieee80211_local *local,
530 				    struct ieee80211_sub_if_data *sdata,
531 				    struct ieee80211_channel *channel,
532 				    unsigned int duration, u64 *cookie,
533 				    struct sk_buff *txskb,
534 				    enum ieee80211_roc_type type)
535 {
536 	struct ieee80211_roc_work *roc, *tmp;
537 	bool queued = false, combine_started = true;
538 	int ret;
539 
540 	lockdep_assert_held(&local->mtx);
541 
542 	if (channel->freq_offset)
543 		/* this may work, but is untested */
544 		return -EOPNOTSUPP;
545 
546 	if (local->use_chanctx && !local->ops->remain_on_channel)
547 		return -EOPNOTSUPP;
548 
549 	roc = kzalloc(sizeof(*roc), GFP_KERNEL);
550 	if (!roc)
551 		return -ENOMEM;
552 
553 	/*
554 	 * If the duration is zero, then the driver
555 	 * wouldn't actually do anything. Set it to
556 	 * 10 for now.
557 	 *
558 	 * TODO: cancel the off-channel operation
559 	 *       when we get the SKB's TX status and
560 	 *       the wait time was zero before.
561 	 */
562 	if (!duration)
563 		duration = 10;
564 
565 	roc->chan = channel;
566 	roc->duration = duration;
567 	roc->req_duration = duration;
568 	roc->frame = txskb;
569 	roc->type = type;
570 	roc->sdata = sdata;
571 
572 	/*
573 	 * cookie is either the roc cookie (for normal roc)
574 	 * or the SKB (for mgmt TX)
575 	 */
576 	if (!txskb) {
577 		roc->cookie = ieee80211_mgmt_tx_cookie(local);
578 		*cookie = roc->cookie;
579 	} else {
580 		roc->mgmt_tx_cookie = *cookie;
581 	}
582 
583 	/* if there's no need to queue, handle it immediately */
584 	if (list_empty(&local->roc_list) &&
585 	    !local->scanning && !ieee80211_is_radar_required(local)) {
586 		/* if not HW assist, just queue & schedule work */
587 		if (!local->ops->remain_on_channel) {
588 			list_add_tail(&roc->list, &local->roc_list);
589 			wiphy_delayed_work_queue(local->hw.wiphy,
590 						 &local->roc_work, 0);
591 		} else {
592 			/* otherwise actually kick it off here
593 			 * (for error handling)
594 			 */
595 			ret = drv_remain_on_channel(local, sdata, channel,
596 						    duration, type);
597 			if (ret) {
598 				kfree(roc);
599 				return ret;
600 			}
601 			roc->started = true;
602 			list_add_tail(&roc->list, &local->roc_list);
603 		}
604 
605 		return 0;
606 	}
607 
608 	/* otherwise handle queueing */
609 
610 	list_for_each_entry(tmp, &local->roc_list, list) {
611 		if (tmp->chan != channel || tmp->sdata != sdata)
612 			continue;
613 
614 		/*
615 		 * Extend this ROC if possible: If it hasn't started, add
616 		 * just after the new one to combine.
617 		 */
618 		if (!tmp->started) {
619 			list_add(&roc->list, &tmp->list);
620 			queued = true;
621 			break;
622 		}
623 
624 		if (!combine_started)
625 			continue;
626 
627 		if (!local->ops->remain_on_channel) {
628 			/* If there's no hardware remain-on-channel, and
629 			 * doing so won't push us over the maximum r-o-c
630 			 * we allow, then we can just add the new one to
631 			 * the list and mark it as having started now.
632 			 * If it would push over the limit, don't try to
633 			 * combine with other started ones (that haven't
634 			 * been running as long) but potentially sort it
635 			 * with others that had the same fate.
636 			 */
637 			unsigned long now = jiffies;
638 			u32 elapsed = jiffies_to_msecs(now - tmp->start_time);
639 			struct wiphy *wiphy = local->hw.wiphy;
640 			u32 max_roc = wiphy->max_remain_on_channel_duration;
641 
642 			if (elapsed + roc->duration > max_roc) {
643 				combine_started = false;
644 				continue;
645 			}
646 
647 			list_add(&roc->list, &tmp->list);
648 			queued = true;
649 			roc->on_channel = tmp->on_channel;
650 			ieee80211_handle_roc_started(roc, now);
651 			ieee80211_recalc_sw_work(local, now);
652 			break;
653 		}
654 
655 		queued = ieee80211_coalesce_hw_started_roc(local, roc, tmp);
656 		if (queued)
657 			break;
658 		/* if it wasn't queued, perhaps it can be combined with
659 		 * another that also couldn't get combined previously,
660 		 * but no need to check for already started ones, since
661 		 * that can't work.
662 		 */
663 		combine_started = false;
664 	}
665 
666 	if (!queued)
667 		list_add_tail(&roc->list, &local->roc_list);
668 
669 	return 0;
670 }
671 
ieee80211_remain_on_channel(struct wiphy * wiphy,struct wireless_dev * wdev,struct ieee80211_channel * chan,unsigned int duration,u64 * cookie)672 int ieee80211_remain_on_channel(struct wiphy *wiphy, struct wireless_dev *wdev,
673 				struct ieee80211_channel *chan,
674 				unsigned int duration, u64 *cookie)
675 {
676 	struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
677 	struct ieee80211_local *local = sdata->local;
678 	int ret;
679 
680 	mutex_lock(&local->mtx);
681 	ret = ieee80211_start_roc_work(local, sdata, chan,
682 				       duration, cookie, NULL,
683 				       IEEE80211_ROC_TYPE_NORMAL);
684 	mutex_unlock(&local->mtx);
685 
686 	return ret;
687 }
688 
ieee80211_cancel_roc(struct ieee80211_local * local,u64 cookie,bool mgmt_tx)689 static int ieee80211_cancel_roc(struct ieee80211_local *local,
690 				u64 cookie, bool mgmt_tx)
691 {
692 	struct ieee80211_roc_work *roc, *tmp, *found = NULL;
693 	int ret;
694 
695 	if (!cookie)
696 		return -ENOENT;
697 
698 	wiphy_work_flush(local->hw.wiphy, &local->hw_roc_start);
699 
700 	mutex_lock(&local->mtx);
701 	list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
702 		if (!mgmt_tx && roc->cookie != cookie)
703 			continue;
704 		else if (mgmt_tx && roc->mgmt_tx_cookie != cookie)
705 			continue;
706 
707 		found = roc;
708 		break;
709 	}
710 
711 	if (!found) {
712 		mutex_unlock(&local->mtx);
713 		return -ENOENT;
714 	}
715 
716 	if (!found->started) {
717 		ieee80211_roc_notify_destroy(found);
718 		goto out_unlock;
719 	}
720 
721 	if (local->ops->remain_on_channel) {
722 		ret = drv_cancel_remain_on_channel(local, roc->sdata);
723 		if (WARN_ON_ONCE(ret)) {
724 			mutex_unlock(&local->mtx);
725 			return ret;
726 		}
727 
728 		/* TODO:
729 		 * if multiple items were combined here then we really shouldn't
730 		 * cancel them all - we should wait for as much time as needed
731 		 * for the longest remaining one, and only then cancel ...
732 		 */
733 		list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
734 			if (!roc->started)
735 				break;
736 			if (roc == found)
737 				found = NULL;
738 			ieee80211_roc_notify_destroy(roc);
739 		}
740 
741 		/* that really must not happen - it was started */
742 		WARN_ON(found);
743 
744 		ieee80211_start_next_roc(local);
745 	} else {
746 		/* go through work struct to return to the operating channel */
747 		found->abort = true;
748 		wiphy_delayed_work_queue(local->hw.wiphy, &local->roc_work, 0);
749 	}
750 
751  out_unlock:
752 	mutex_unlock(&local->mtx);
753 
754 	return 0;
755 }
756 
ieee80211_cancel_remain_on_channel(struct wiphy * wiphy,struct wireless_dev * wdev,u64 cookie)757 int ieee80211_cancel_remain_on_channel(struct wiphy *wiphy,
758 				       struct wireless_dev *wdev, u64 cookie)
759 {
760 	struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
761 	struct ieee80211_local *local = sdata->local;
762 
763 	return ieee80211_cancel_roc(local, cookie, false);
764 }
765 
ieee80211_mgmt_tx(struct wiphy * wiphy,struct wireless_dev * wdev,struct cfg80211_mgmt_tx_params * params,u64 * cookie)766 int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
767 		      struct cfg80211_mgmt_tx_params *params, u64 *cookie)
768 {
769 	struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
770 	struct ieee80211_local *local = sdata->local;
771 	struct sk_buff *skb;
772 	struct sta_info *sta = NULL;
773 	const struct ieee80211_mgmt *mgmt = (void *)params->buf;
774 	bool need_offchan = false;
775 	bool mlo_sta = false;
776 	int link_id = -1;
777 	u32 flags;
778 	int ret;
779 	u8 *data;
780 
781 	if (params->dont_wait_for_ack)
782 		flags = IEEE80211_TX_CTL_NO_ACK;
783 	else
784 		flags = IEEE80211_TX_INTFL_NL80211_FRAME_TX |
785 			IEEE80211_TX_CTL_REQ_TX_STATUS;
786 
787 	if (params->no_cck)
788 		flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
789 
790 	switch (sdata->vif.type) {
791 	case NL80211_IFTYPE_ADHOC:
792 		if (!sdata->vif.cfg.ibss_joined)
793 			need_offchan = true;
794 #ifdef CONFIG_MAC80211_MESH
795 		fallthrough;
796 	case NL80211_IFTYPE_MESH_POINT:
797 		if (ieee80211_vif_is_mesh(&sdata->vif) &&
798 		    !sdata->u.mesh.mesh_id_len)
799 			need_offchan = true;
800 #endif
801 		fallthrough;
802 	case NL80211_IFTYPE_AP:
803 	case NL80211_IFTYPE_AP_VLAN:
804 	case NL80211_IFTYPE_P2P_GO:
805 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
806 		    !ieee80211_vif_is_mesh(&sdata->vif) &&
807 		    !sdata->bss->active)
808 			need_offchan = true;
809 
810 		rcu_read_lock();
811 		sta = sta_info_get_bss(sdata, mgmt->da);
812 		mlo_sta = sta && sta->sta.mlo;
813 
814 		if (!ieee80211_is_action(mgmt->frame_control) ||
815 		    mgmt->u.action.category == WLAN_CATEGORY_PUBLIC ||
816 		    mgmt->u.action.category == WLAN_CATEGORY_SELF_PROTECTED ||
817 		    mgmt->u.action.category == WLAN_CATEGORY_SPECTRUM_MGMT) {
818 			rcu_read_unlock();
819 			break;
820 		}
821 
822 		if (!sta) {
823 			rcu_read_unlock();
824 			return -ENOLINK;
825 		}
826 		if (params->link_id >= 0 &&
827 		    !(sta->sta.valid_links & BIT(params->link_id))) {
828 			rcu_read_unlock();
829 			return -ENOLINK;
830 		}
831 		link_id = params->link_id;
832 		rcu_read_unlock();
833 		break;
834 	case NL80211_IFTYPE_STATION:
835 	case NL80211_IFTYPE_P2P_CLIENT:
836 		sdata_lock(sdata);
837 		if (!sdata->u.mgd.associated ||
838 		    (params->offchan && params->wait &&
839 		     local->ops->remain_on_channel &&
840 		     memcmp(sdata->vif.cfg.ap_addr, mgmt->bssid, ETH_ALEN)))
841 			need_offchan = true;
842 		sdata_unlock(sdata);
843 		break;
844 	case NL80211_IFTYPE_P2P_DEVICE:
845 		need_offchan = true;
846 		break;
847 	case NL80211_IFTYPE_NAN:
848 	default:
849 		return -EOPNOTSUPP;
850 	}
851 
852 	/* configurations requiring offchan cannot work if no channel has been
853 	 * specified
854 	 */
855 	if (need_offchan && !params->chan)
856 		return -EINVAL;
857 
858 	mutex_lock(&local->mtx);
859 
860 	/* Check if the operating channel is the requested channel */
861 	if (!params->chan && mlo_sta) {
862 		need_offchan = false;
863 	} else if (!need_offchan) {
864 		struct ieee80211_chanctx_conf *chanctx_conf = NULL;
865 		int i;
866 
867 		rcu_read_lock();
868 		/* Check all the links first */
869 		for (i = 0; i < ARRAY_SIZE(sdata->vif.link_conf); i++) {
870 			struct ieee80211_bss_conf *conf;
871 
872 			conf = rcu_dereference(sdata->vif.link_conf[i]);
873 			if (!conf)
874 				continue;
875 
876 			chanctx_conf = rcu_dereference(conf->chanctx_conf);
877 			if (!chanctx_conf)
878 				continue;
879 
880 			if (mlo_sta && params->chan == chanctx_conf->def.chan &&
881 			    ether_addr_equal(sdata->vif.addr, mgmt->sa)) {
882 				link_id = i;
883 				break;
884 			}
885 
886 			if (ether_addr_equal(conf->addr, mgmt->sa))
887 				break;
888 
889 			chanctx_conf = NULL;
890 		}
891 
892 		if (chanctx_conf) {
893 			need_offchan = params->chan &&
894 				       (params->chan !=
895 					chanctx_conf->def.chan);
896 		} else {
897 			need_offchan = true;
898 		}
899 		rcu_read_unlock();
900 	}
901 
902 	if (need_offchan && !params->offchan) {
903 		ret = -EBUSY;
904 		goto out_unlock;
905 	}
906 
907 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + params->len);
908 	if (!skb) {
909 		ret = -ENOMEM;
910 		goto out_unlock;
911 	}
912 	skb_reserve(skb, local->hw.extra_tx_headroom);
913 
914 	data = skb_put_data(skb, params->buf, params->len);
915 
916 	/* Update CSA counters */
917 	if (sdata->vif.bss_conf.csa_active &&
918 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
919 	     sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
920 	     sdata->vif.type == NL80211_IFTYPE_ADHOC) &&
921 	    params->n_csa_offsets) {
922 		int i;
923 		struct beacon_data *beacon = NULL;
924 
925 		rcu_read_lock();
926 
927 		if (sdata->vif.type == NL80211_IFTYPE_AP)
928 			beacon = rcu_dereference(sdata->deflink.u.ap.beacon);
929 		else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
930 			beacon = rcu_dereference(sdata->u.ibss.presp);
931 		else if (ieee80211_vif_is_mesh(&sdata->vif))
932 			beacon = rcu_dereference(sdata->u.mesh.beacon);
933 
934 		if (beacon)
935 			for (i = 0; i < params->n_csa_offsets; i++)
936 				data[params->csa_offsets[i]] =
937 					beacon->cntdwn_current_counter;
938 
939 		rcu_read_unlock();
940 	}
941 
942 	IEEE80211_SKB_CB(skb)->flags = flags;
943 
944 	skb->dev = sdata->dev;
945 
946 	if (!params->dont_wait_for_ack) {
947 		/* make a copy to preserve the frame contents
948 		 * in case of encryption.
949 		 */
950 		ret = ieee80211_attach_ack_skb(local, skb, cookie, GFP_KERNEL);
951 		if (ret) {
952 			kfree_skb(skb);
953 			goto out_unlock;
954 		}
955 	} else {
956 		/* Assign a dummy non-zero cookie, it's not sent to
957 		 * userspace in this case but we rely on its value
958 		 * internally in the need_offchan case to distinguish
959 		 * mgmt-tx from remain-on-channel.
960 		 */
961 		*cookie = 0xffffffff;
962 	}
963 
964 	if (!need_offchan) {
965 		ieee80211_tx_skb_tid(sdata, skb, 7, link_id);
966 		ret = 0;
967 		goto out_unlock;
968 	}
969 
970 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_TX_OFFCHAN |
971 					IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
972 	if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
973 		IEEE80211_SKB_CB(skb)->hw_queue =
974 			local->hw.offchannel_tx_hw_queue;
975 
976 	/* This will handle all kinds of coalescing and immediate TX */
977 	ret = ieee80211_start_roc_work(local, sdata, params->chan,
978 				       params->wait, cookie, skb,
979 				       IEEE80211_ROC_TYPE_MGMT_TX);
980 	if (ret)
981 		ieee80211_free_txskb(&local->hw, skb);
982  out_unlock:
983 	mutex_unlock(&local->mtx);
984 	return ret;
985 }
986 
ieee80211_mgmt_tx_cancel_wait(struct wiphy * wiphy,struct wireless_dev * wdev,u64 cookie)987 int ieee80211_mgmt_tx_cancel_wait(struct wiphy *wiphy,
988 				  struct wireless_dev *wdev, u64 cookie)
989 {
990 	struct ieee80211_local *local = wiphy_priv(wiphy);
991 
992 	return ieee80211_cancel_roc(local, cookie, true);
993 }
994 
ieee80211_roc_setup(struct ieee80211_local * local)995 void ieee80211_roc_setup(struct ieee80211_local *local)
996 {
997 	wiphy_work_init(&local->hw_roc_start, ieee80211_hw_roc_start);
998 	wiphy_work_init(&local->hw_roc_done, ieee80211_hw_roc_done);
999 	wiphy_delayed_work_init(&local->roc_work, ieee80211_roc_work);
1000 	INIT_LIST_HEAD(&local->roc_list);
1001 }
1002 
ieee80211_roc_purge(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata)1003 void ieee80211_roc_purge(struct ieee80211_local *local,
1004 			 struct ieee80211_sub_if_data *sdata)
1005 {
1006 	struct ieee80211_roc_work *roc, *tmp;
1007 	bool work_to_do = false;
1008 
1009 	mutex_lock(&local->mtx);
1010 	list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
1011 		if (sdata && roc->sdata != sdata)
1012 			continue;
1013 
1014 		if (roc->started) {
1015 			if (local->ops->remain_on_channel) {
1016 				/* can race, so ignore return value */
1017 				drv_cancel_remain_on_channel(local, sdata);
1018 				ieee80211_roc_notify_destroy(roc);
1019 			} else {
1020 				roc->abort = true;
1021 				work_to_do = true;
1022 			}
1023 		} else {
1024 			ieee80211_roc_notify_destroy(roc);
1025 		}
1026 	}
1027 	if (work_to_do)
1028 		__ieee80211_roc_work(local);
1029 	mutex_unlock(&local->mtx);
1030 }
1031