xref: /linux/net/mac80211/chan.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /*
2  * mac80211 - channel management
3  */
4 
5 #include <linux/nl80211.h>
6 #include <linux/export.h>
7 #include <linux/rtnetlink.h>
8 #include <net/cfg80211.h>
9 #include "ieee80211_i.h"
10 #include "driver-ops.h"
11 
12 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
13 					  struct ieee80211_chanctx *ctx)
14 {
15 	struct ieee80211_sub_if_data *sdata;
16 	int num = 0;
17 
18 	lockdep_assert_held(&local->chanctx_mtx);
19 
20 	list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
21 		num++;
22 
23 	return num;
24 }
25 
26 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
27 					  struct ieee80211_chanctx *ctx)
28 {
29 	struct ieee80211_sub_if_data *sdata;
30 	int num = 0;
31 
32 	lockdep_assert_held(&local->chanctx_mtx);
33 
34 	list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
35 		num++;
36 
37 	return num;
38 }
39 
40 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
41 			       struct ieee80211_chanctx *ctx)
42 {
43 	return ieee80211_chanctx_num_assigned(local, ctx) +
44 	       ieee80211_chanctx_num_reserved(local, ctx);
45 }
46 
47 static int ieee80211_num_chanctx(struct ieee80211_local *local)
48 {
49 	struct ieee80211_chanctx *ctx;
50 	int num = 0;
51 
52 	lockdep_assert_held(&local->chanctx_mtx);
53 
54 	list_for_each_entry(ctx, &local->chanctx_list, list)
55 		num++;
56 
57 	return num;
58 }
59 
60 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
61 {
62 	lockdep_assert_held(&local->chanctx_mtx);
63 	return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
64 }
65 
66 static struct ieee80211_chanctx *
67 ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
68 {
69 	struct ieee80211_local *local __maybe_unused = sdata->local;
70 	struct ieee80211_chanctx_conf *conf;
71 
72 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
73 					 lockdep_is_held(&local->chanctx_mtx));
74 	if (!conf)
75 		return NULL;
76 
77 	return container_of(conf, struct ieee80211_chanctx, conf);
78 }
79 
80 static const struct cfg80211_chan_def *
81 ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
82 				   struct ieee80211_chanctx *ctx,
83 				   const struct cfg80211_chan_def *compat)
84 {
85 	struct ieee80211_sub_if_data *sdata;
86 
87 	lockdep_assert_held(&local->chanctx_mtx);
88 
89 	list_for_each_entry(sdata, &ctx->reserved_vifs,
90 			    reserved_chanctx_list) {
91 		if (!compat)
92 			compat = &sdata->reserved_chandef;
93 
94 		compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
95 						     compat);
96 		if (!compat)
97 			break;
98 	}
99 
100 	return compat;
101 }
102 
103 static const struct cfg80211_chan_def *
104 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
105 				       struct ieee80211_chanctx *ctx,
106 				       const struct cfg80211_chan_def *compat)
107 {
108 	struct ieee80211_sub_if_data *sdata;
109 
110 	lockdep_assert_held(&local->chanctx_mtx);
111 
112 	list_for_each_entry(sdata, &ctx->assigned_vifs,
113 			    assigned_chanctx_list) {
114 		if (sdata->reserved_chanctx != NULL)
115 			continue;
116 
117 		if (!compat)
118 			compat = &sdata->vif.bss_conf.chandef;
119 
120 		compat = cfg80211_chandef_compatible(
121 				&sdata->vif.bss_conf.chandef, compat);
122 		if (!compat)
123 			break;
124 	}
125 
126 	return compat;
127 }
128 
129 static const struct cfg80211_chan_def *
130 ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
131 				   struct ieee80211_chanctx *ctx,
132 				   const struct cfg80211_chan_def *compat)
133 {
134 	lockdep_assert_held(&local->chanctx_mtx);
135 
136 	compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
137 	if (!compat)
138 		return NULL;
139 
140 	compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
141 	if (!compat)
142 		return NULL;
143 
144 	return compat;
145 }
146 
147 static bool
148 ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
149 				      struct ieee80211_chanctx *ctx,
150 				      const struct cfg80211_chan_def *def)
151 {
152 	lockdep_assert_held(&local->chanctx_mtx);
153 
154 	if (ieee80211_chanctx_combined_chandef(local, ctx, def))
155 		return true;
156 
157 	if (!list_empty(&ctx->reserved_vifs) &&
158 	    ieee80211_chanctx_reserved_chandef(local, ctx, def))
159 		return true;
160 
161 	return false;
162 }
163 
164 static struct ieee80211_chanctx *
165 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
166 				   const struct cfg80211_chan_def *chandef,
167 				   enum ieee80211_chanctx_mode mode)
168 {
169 	struct ieee80211_chanctx *ctx;
170 
171 	lockdep_assert_held(&local->chanctx_mtx);
172 
173 	if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
174 		return NULL;
175 
176 	list_for_each_entry(ctx, &local->chanctx_list, list) {
177 		if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
178 			continue;
179 
180 		if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
181 			continue;
182 
183 		if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
184 							   chandef))
185 			continue;
186 
187 		return ctx;
188 	}
189 
190 	return NULL;
191 }
192 
193 static enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
194 {
195 	switch (sta->bandwidth) {
196 	case IEEE80211_STA_RX_BW_20:
197 		if (sta->ht_cap.ht_supported)
198 			return NL80211_CHAN_WIDTH_20;
199 		else
200 			return NL80211_CHAN_WIDTH_20_NOHT;
201 	case IEEE80211_STA_RX_BW_40:
202 		return NL80211_CHAN_WIDTH_40;
203 	case IEEE80211_STA_RX_BW_80:
204 		return NL80211_CHAN_WIDTH_80;
205 	case IEEE80211_STA_RX_BW_160:
206 		/*
207 		 * This applied for both 160 and 80+80. since we use
208 		 * the returned value to consider degradation of
209 		 * ctx->conf.min_def, we have to make sure to take
210 		 * the bigger one (NL80211_CHAN_WIDTH_160).
211 		 * Otherwise we might try degrading even when not
212 		 * needed, as the max required sta_bw returned (80+80)
213 		 * might be smaller than the configured bw (160).
214 		 */
215 		return NL80211_CHAN_WIDTH_160;
216 	default:
217 		WARN_ON(1);
218 		return NL80211_CHAN_WIDTH_20;
219 	}
220 }
221 
222 static enum nl80211_chan_width
223 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
224 {
225 	enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
226 	struct sta_info *sta;
227 
228 	rcu_read_lock();
229 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
230 		if (sdata != sta->sdata &&
231 		    !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
232 			continue;
233 
234 		if (!sta->uploaded)
235 			continue;
236 
237 		max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
238 	}
239 	rcu_read_unlock();
240 
241 	return max_bw;
242 }
243 
244 static enum nl80211_chan_width
245 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
246 				      struct ieee80211_chanctx_conf *conf)
247 {
248 	struct ieee80211_sub_if_data *sdata;
249 	enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
250 
251 	rcu_read_lock();
252 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
253 		struct ieee80211_vif *vif = &sdata->vif;
254 		enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
255 
256 		if (!ieee80211_sdata_running(sdata))
257 			continue;
258 
259 		if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
260 			continue;
261 
262 		switch (vif->type) {
263 		case NL80211_IFTYPE_AP:
264 		case NL80211_IFTYPE_AP_VLAN:
265 			width = ieee80211_get_max_required_bw(sdata);
266 			break;
267 		case NL80211_IFTYPE_P2P_DEVICE:
268 			continue;
269 		case NL80211_IFTYPE_STATION:
270 		case NL80211_IFTYPE_ADHOC:
271 		case NL80211_IFTYPE_WDS:
272 		case NL80211_IFTYPE_MESH_POINT:
273 		case NL80211_IFTYPE_OCB:
274 			width = vif->bss_conf.chandef.width;
275 			break;
276 		case NL80211_IFTYPE_UNSPECIFIED:
277 		case NUM_NL80211_IFTYPES:
278 		case NL80211_IFTYPE_MONITOR:
279 		case NL80211_IFTYPE_P2P_CLIENT:
280 		case NL80211_IFTYPE_P2P_GO:
281 			WARN_ON_ONCE(1);
282 		}
283 		max_bw = max(max_bw, width);
284 	}
285 
286 	/* use the configured bandwidth in case of monitor interface */
287 	sdata = rcu_dereference(local->monitor_sdata);
288 	if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
289 		max_bw = max(max_bw, conf->def.width);
290 
291 	rcu_read_unlock();
292 
293 	return max_bw;
294 }
295 
296 /*
297  * recalc the min required chan width of the channel context, which is
298  * the max of min required widths of all the interfaces bound to this
299  * channel context.
300  */
301 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
302 				      struct ieee80211_chanctx *ctx)
303 {
304 	enum nl80211_chan_width max_bw;
305 	struct cfg80211_chan_def min_def;
306 
307 	lockdep_assert_held(&local->chanctx_mtx);
308 
309 	/* don't optimize 5MHz, 10MHz, and radar_enabled confs */
310 	if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
311 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
312 	    ctx->conf.radar_enabled) {
313 		ctx->conf.min_def = ctx->conf.def;
314 		return;
315 	}
316 
317 	max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
318 
319 	/* downgrade chandef up to max_bw */
320 	min_def = ctx->conf.def;
321 	while (min_def.width > max_bw)
322 		ieee80211_chandef_downgrade(&min_def);
323 
324 	if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
325 		return;
326 
327 	ctx->conf.min_def = min_def;
328 	if (!ctx->driver_present)
329 		return;
330 
331 	drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
332 }
333 
334 static void ieee80211_change_chanctx(struct ieee80211_local *local,
335 				     struct ieee80211_chanctx *ctx,
336 				     const struct cfg80211_chan_def *chandef)
337 {
338 	if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
339 		return;
340 
341 	WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
342 
343 	ctx->conf.def = *chandef;
344 	drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
345 	ieee80211_recalc_chanctx_min_def(local, ctx);
346 
347 	if (!local->use_chanctx) {
348 		local->_oper_chandef = *chandef;
349 		ieee80211_hw_config(local, 0);
350 	}
351 }
352 
353 static struct ieee80211_chanctx *
354 ieee80211_find_chanctx(struct ieee80211_local *local,
355 		       const struct cfg80211_chan_def *chandef,
356 		       enum ieee80211_chanctx_mode mode)
357 {
358 	struct ieee80211_chanctx *ctx;
359 
360 	lockdep_assert_held(&local->chanctx_mtx);
361 
362 	if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
363 		return NULL;
364 
365 	list_for_each_entry(ctx, &local->chanctx_list, list) {
366 		const struct cfg80211_chan_def *compat;
367 
368 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
369 			continue;
370 
371 		if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
372 			continue;
373 
374 		compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
375 		if (!compat)
376 			continue;
377 
378 		compat = ieee80211_chanctx_reserved_chandef(local, ctx,
379 							    compat);
380 		if (!compat)
381 			continue;
382 
383 		ieee80211_change_chanctx(local, ctx, compat);
384 
385 		return ctx;
386 	}
387 
388 	return NULL;
389 }
390 
391 bool ieee80211_is_radar_required(struct ieee80211_local *local)
392 {
393 	struct ieee80211_sub_if_data *sdata;
394 
395 	lockdep_assert_held(&local->mtx);
396 
397 	rcu_read_lock();
398 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
399 		if (sdata->radar_required) {
400 			rcu_read_unlock();
401 			return true;
402 		}
403 	}
404 	rcu_read_unlock();
405 
406 	return false;
407 }
408 
409 static bool
410 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
411 				 struct ieee80211_chanctx *ctx)
412 {
413 	struct ieee80211_chanctx_conf *conf = &ctx->conf;
414 	struct ieee80211_sub_if_data *sdata;
415 	bool required = false;
416 
417 	lockdep_assert_held(&local->chanctx_mtx);
418 	lockdep_assert_held(&local->mtx);
419 
420 	rcu_read_lock();
421 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
422 		if (!ieee80211_sdata_running(sdata))
423 			continue;
424 		if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
425 			continue;
426 		if (!sdata->radar_required)
427 			continue;
428 
429 		required = true;
430 		break;
431 	}
432 	rcu_read_unlock();
433 
434 	return required;
435 }
436 
437 static struct ieee80211_chanctx *
438 ieee80211_alloc_chanctx(struct ieee80211_local *local,
439 			const struct cfg80211_chan_def *chandef,
440 			enum ieee80211_chanctx_mode mode)
441 {
442 	struct ieee80211_chanctx *ctx;
443 
444 	lockdep_assert_held(&local->chanctx_mtx);
445 
446 	ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
447 	if (!ctx)
448 		return NULL;
449 
450 	INIT_LIST_HEAD(&ctx->assigned_vifs);
451 	INIT_LIST_HEAD(&ctx->reserved_vifs);
452 	ctx->conf.def = *chandef;
453 	ctx->conf.rx_chains_static = 1;
454 	ctx->conf.rx_chains_dynamic = 1;
455 	ctx->mode = mode;
456 	ctx->conf.radar_enabled = false;
457 	ieee80211_recalc_chanctx_min_def(local, ctx);
458 
459 	return ctx;
460 }
461 
462 static int ieee80211_add_chanctx(struct ieee80211_local *local,
463 				 struct ieee80211_chanctx *ctx)
464 {
465 	u32 changed;
466 	int err;
467 
468 	lockdep_assert_held(&local->mtx);
469 	lockdep_assert_held(&local->chanctx_mtx);
470 
471 	if (!local->use_chanctx)
472 		local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
473 
474 	/* turn idle off *before* setting channel -- some drivers need that */
475 	changed = ieee80211_idle_off(local);
476 	if (changed)
477 		ieee80211_hw_config(local, changed);
478 
479 	if (!local->use_chanctx) {
480 		local->_oper_chandef = ctx->conf.def;
481 		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
482 	} else {
483 		err = drv_add_chanctx(local, ctx);
484 		if (err) {
485 			ieee80211_recalc_idle(local);
486 			return err;
487 		}
488 	}
489 
490 	return 0;
491 }
492 
493 static struct ieee80211_chanctx *
494 ieee80211_new_chanctx(struct ieee80211_local *local,
495 		      const struct cfg80211_chan_def *chandef,
496 		      enum ieee80211_chanctx_mode mode)
497 {
498 	struct ieee80211_chanctx *ctx;
499 	int err;
500 
501 	lockdep_assert_held(&local->mtx);
502 	lockdep_assert_held(&local->chanctx_mtx);
503 
504 	ctx = ieee80211_alloc_chanctx(local, chandef, mode);
505 	if (!ctx)
506 		return ERR_PTR(-ENOMEM);
507 
508 	err = ieee80211_add_chanctx(local, ctx);
509 	if (err) {
510 		kfree(ctx);
511 		return ERR_PTR(err);
512 	}
513 
514 	list_add_rcu(&ctx->list, &local->chanctx_list);
515 	return ctx;
516 }
517 
518 static void ieee80211_del_chanctx(struct ieee80211_local *local,
519 				  struct ieee80211_chanctx *ctx)
520 {
521 	lockdep_assert_held(&local->chanctx_mtx);
522 
523 	if (!local->use_chanctx) {
524 		struct cfg80211_chan_def *chandef = &local->_oper_chandef;
525 		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
526 		chandef->center_freq1 = chandef->chan->center_freq;
527 		chandef->center_freq2 = 0;
528 
529 		/* NOTE: Disabling radar is only valid here for
530 		 * single channel context. To be sure, check it ...
531 		 */
532 		WARN_ON(local->hw.conf.radar_enabled &&
533 			!list_empty(&local->chanctx_list));
534 
535 		local->hw.conf.radar_enabled = false;
536 
537 		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
538 	} else {
539 		drv_remove_chanctx(local, ctx);
540 	}
541 
542 	ieee80211_recalc_idle(local);
543 }
544 
545 static void ieee80211_free_chanctx(struct ieee80211_local *local,
546 				   struct ieee80211_chanctx *ctx)
547 {
548 	lockdep_assert_held(&local->chanctx_mtx);
549 
550 	WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
551 
552 	list_del_rcu(&ctx->list);
553 	ieee80211_del_chanctx(local, ctx);
554 	kfree_rcu(ctx, rcu_head);
555 }
556 
557 static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
558 					      struct ieee80211_chanctx *ctx)
559 {
560 	struct ieee80211_chanctx_conf *conf = &ctx->conf;
561 	struct ieee80211_sub_if_data *sdata;
562 	const struct cfg80211_chan_def *compat = NULL;
563 
564 	lockdep_assert_held(&local->chanctx_mtx);
565 
566 	rcu_read_lock();
567 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
568 
569 		if (!ieee80211_sdata_running(sdata))
570 			continue;
571 		if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
572 			continue;
573 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
574 			continue;
575 
576 		if (!compat)
577 			compat = &sdata->vif.bss_conf.chandef;
578 
579 		compat = cfg80211_chandef_compatible(
580 				&sdata->vif.bss_conf.chandef, compat);
581 		if (WARN_ON_ONCE(!compat))
582 			break;
583 	}
584 	rcu_read_unlock();
585 
586 	if (!compat)
587 		return;
588 
589 	ieee80211_change_chanctx(local, ctx, compat);
590 }
591 
592 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
593 					   struct ieee80211_chanctx *chanctx)
594 {
595 	bool radar_enabled;
596 
597 	lockdep_assert_held(&local->chanctx_mtx);
598 	/* for ieee80211_is_radar_required */
599 	lockdep_assert_held(&local->mtx);
600 
601 	radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
602 
603 	if (radar_enabled == chanctx->conf.radar_enabled)
604 		return;
605 
606 	chanctx->conf.radar_enabled = radar_enabled;
607 
608 	if (!local->use_chanctx) {
609 		local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
610 		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
611 	}
612 
613 	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
614 }
615 
616 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
617 					struct ieee80211_chanctx *new_ctx)
618 {
619 	struct ieee80211_local *local = sdata->local;
620 	struct ieee80211_chanctx_conf *conf;
621 	struct ieee80211_chanctx *curr_ctx = NULL;
622 	int ret = 0;
623 
624 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
625 					 lockdep_is_held(&local->chanctx_mtx));
626 
627 	if (conf) {
628 		curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
629 
630 		drv_unassign_vif_chanctx(local, sdata, curr_ctx);
631 		conf = NULL;
632 		list_del(&sdata->assigned_chanctx_list);
633 	}
634 
635 	if (new_ctx) {
636 		ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
637 		if (ret)
638 			goto out;
639 
640 		conf = &new_ctx->conf;
641 		list_add(&sdata->assigned_chanctx_list,
642 			 &new_ctx->assigned_vifs);
643 	}
644 
645 out:
646 	rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
647 
648 	sdata->vif.bss_conf.idle = !conf;
649 
650 	if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
651 		ieee80211_recalc_chanctx_chantype(local, curr_ctx);
652 		ieee80211_recalc_smps_chanctx(local, curr_ctx);
653 		ieee80211_recalc_radar_chanctx(local, curr_ctx);
654 		ieee80211_recalc_chanctx_min_def(local, curr_ctx);
655 	}
656 
657 	if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
658 		ieee80211_recalc_txpower(sdata, false);
659 		ieee80211_recalc_chanctx_min_def(local, new_ctx);
660 	}
661 
662 	if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
663 	    sdata->vif.type != NL80211_IFTYPE_MONITOR)
664 		ieee80211_bss_info_change_notify(sdata,
665 						 BSS_CHANGED_IDLE);
666 
667 	ieee80211_check_fast_xmit_iface(sdata);
668 
669 	return ret;
670 }
671 
672 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
673 				   struct ieee80211_chanctx *chanctx)
674 {
675 	struct ieee80211_sub_if_data *sdata;
676 	u8 rx_chains_static, rx_chains_dynamic;
677 
678 	lockdep_assert_held(&local->chanctx_mtx);
679 
680 	rx_chains_static = 1;
681 	rx_chains_dynamic = 1;
682 
683 	rcu_read_lock();
684 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
685 		u8 needed_static, needed_dynamic;
686 
687 		if (!ieee80211_sdata_running(sdata))
688 			continue;
689 
690 		if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
691 						&chanctx->conf)
692 			continue;
693 
694 		switch (sdata->vif.type) {
695 		case NL80211_IFTYPE_P2P_DEVICE:
696 			continue;
697 		case NL80211_IFTYPE_STATION:
698 			if (!sdata->u.mgd.associated)
699 				continue;
700 			break;
701 		case NL80211_IFTYPE_AP_VLAN:
702 			continue;
703 		case NL80211_IFTYPE_AP:
704 		case NL80211_IFTYPE_ADHOC:
705 		case NL80211_IFTYPE_WDS:
706 		case NL80211_IFTYPE_MESH_POINT:
707 		case NL80211_IFTYPE_OCB:
708 			break;
709 		default:
710 			WARN_ON_ONCE(1);
711 		}
712 
713 		switch (sdata->smps_mode) {
714 		default:
715 			WARN_ONCE(1, "Invalid SMPS mode %d\n",
716 				  sdata->smps_mode);
717 			/* fall through */
718 		case IEEE80211_SMPS_OFF:
719 			needed_static = sdata->needed_rx_chains;
720 			needed_dynamic = sdata->needed_rx_chains;
721 			break;
722 		case IEEE80211_SMPS_DYNAMIC:
723 			needed_static = 1;
724 			needed_dynamic = sdata->needed_rx_chains;
725 			break;
726 		case IEEE80211_SMPS_STATIC:
727 			needed_static = 1;
728 			needed_dynamic = 1;
729 			break;
730 		}
731 
732 		rx_chains_static = max(rx_chains_static, needed_static);
733 		rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
734 	}
735 
736 	/* Disable SMPS for the monitor interface */
737 	sdata = rcu_dereference(local->monitor_sdata);
738 	if (sdata &&
739 	    rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
740 		rx_chains_dynamic = rx_chains_static = local->rx_chains;
741 
742 	rcu_read_unlock();
743 
744 	if (!local->use_chanctx) {
745 		if (rx_chains_static > 1)
746 			local->smps_mode = IEEE80211_SMPS_OFF;
747 		else if (rx_chains_dynamic > 1)
748 			local->smps_mode = IEEE80211_SMPS_DYNAMIC;
749 		else
750 			local->smps_mode = IEEE80211_SMPS_STATIC;
751 		ieee80211_hw_config(local, 0);
752 	}
753 
754 	if (rx_chains_static == chanctx->conf.rx_chains_static &&
755 	    rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
756 		return;
757 
758 	chanctx->conf.rx_chains_static = rx_chains_static;
759 	chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
760 	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
761 }
762 
763 static void
764 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
765 				      bool clear)
766 {
767 	struct ieee80211_local *local __maybe_unused = sdata->local;
768 	struct ieee80211_sub_if_data *vlan;
769 	struct ieee80211_chanctx_conf *conf;
770 
771 	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
772 		return;
773 
774 	lockdep_assert_held(&local->mtx);
775 
776 	/* Check that conf exists, even when clearing this function
777 	 * must be called with the AP's channel context still there
778 	 * as it would otherwise cause VLANs to have an invalid
779 	 * channel context pointer for a while, possibly pointing
780 	 * to a channel context that has already been freed.
781 	 */
782 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
783 					 lockdep_is_held(&local->chanctx_mtx));
784 	WARN_ON(!conf);
785 
786 	if (clear)
787 		conf = NULL;
788 
789 	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
790 		rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
791 }
792 
793 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
794 					 bool clear)
795 {
796 	struct ieee80211_local *local = sdata->local;
797 
798 	mutex_lock(&local->chanctx_mtx);
799 
800 	__ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
801 
802 	mutex_unlock(&local->chanctx_mtx);
803 }
804 
805 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
806 {
807 	struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
808 
809 	lockdep_assert_held(&sdata->local->chanctx_mtx);
810 
811 	if (WARN_ON(!ctx))
812 		return -EINVAL;
813 
814 	list_del(&sdata->reserved_chanctx_list);
815 	sdata->reserved_chanctx = NULL;
816 
817 	if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
818 		if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
819 			if (WARN_ON(!ctx->replace_ctx))
820 				return -EINVAL;
821 
822 			WARN_ON(ctx->replace_ctx->replace_state !=
823 			        IEEE80211_CHANCTX_WILL_BE_REPLACED);
824 			WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
825 
826 			ctx->replace_ctx->replace_ctx = NULL;
827 			ctx->replace_ctx->replace_state =
828 					IEEE80211_CHANCTX_REPLACE_NONE;
829 
830 			list_del_rcu(&ctx->list);
831 			kfree_rcu(ctx, rcu_head);
832 		} else {
833 			ieee80211_free_chanctx(sdata->local, ctx);
834 		}
835 	}
836 
837 	return 0;
838 }
839 
840 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
841 				  const struct cfg80211_chan_def *chandef,
842 				  enum ieee80211_chanctx_mode mode,
843 				  bool radar_required)
844 {
845 	struct ieee80211_local *local = sdata->local;
846 	struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
847 
848 	lockdep_assert_held(&local->chanctx_mtx);
849 
850 	curr_ctx = ieee80211_vif_get_chanctx(sdata);
851 	if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
852 		return -ENOTSUPP;
853 
854 	new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
855 	if (!new_ctx) {
856 		if (ieee80211_can_create_new_chanctx(local)) {
857 			new_ctx = ieee80211_new_chanctx(local, chandef, mode);
858 			if (IS_ERR(new_ctx))
859 				return PTR_ERR(new_ctx);
860 		} else {
861 			if (!curr_ctx ||
862 			    (curr_ctx->replace_state ==
863 			     IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
864 			    !list_empty(&curr_ctx->reserved_vifs)) {
865 				/*
866 				 * Another vif already requested this context
867 				 * for a reservation. Find another one hoping
868 				 * all vifs assigned to it will also switch
869 				 * soon enough.
870 				 *
871 				 * TODO: This needs a little more work as some
872 				 * cases (more than 2 chanctx capable devices)
873 				 * may fail which could otherwise succeed
874 				 * provided some channel context juggling was
875 				 * performed.
876 				 *
877 				 * Consider ctx1..3, vif1..6, each ctx has 2
878 				 * vifs. vif1 and vif2 from ctx1 request new
879 				 * different chandefs starting 2 in-place
880 				 * reserations with ctx4 and ctx5 replacing
881 				 * ctx1 and ctx2 respectively. Next vif5 and
882 				 * vif6 from ctx3 reserve ctx4. If vif3 and
883 				 * vif4 remain on ctx2 as they are then this
884 				 * fails unless `replace_ctx` from ctx5 is
885 				 * replaced with ctx3.
886 				 */
887 				list_for_each_entry(ctx, &local->chanctx_list,
888 						    list) {
889 					if (ctx->replace_state !=
890 					    IEEE80211_CHANCTX_REPLACE_NONE)
891 						continue;
892 
893 					if (!list_empty(&ctx->reserved_vifs))
894 						continue;
895 
896 					curr_ctx = ctx;
897 					break;
898 				}
899 			}
900 
901 			/*
902 			 * If that's true then all available contexts already
903 			 * have reservations and cannot be used.
904 			 */
905 			if (!curr_ctx ||
906 			    (curr_ctx->replace_state ==
907 			     IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
908 			    !list_empty(&curr_ctx->reserved_vifs))
909 				return -EBUSY;
910 
911 			new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
912 			if (!new_ctx)
913 				return -ENOMEM;
914 
915 			new_ctx->replace_ctx = curr_ctx;
916 			new_ctx->replace_state =
917 					IEEE80211_CHANCTX_REPLACES_OTHER;
918 
919 			curr_ctx->replace_ctx = new_ctx;
920 			curr_ctx->replace_state =
921 					IEEE80211_CHANCTX_WILL_BE_REPLACED;
922 
923 			list_add_rcu(&new_ctx->list, &local->chanctx_list);
924 		}
925 	}
926 
927 	list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
928 	sdata->reserved_chanctx = new_ctx;
929 	sdata->reserved_chandef = *chandef;
930 	sdata->reserved_radar_required = radar_required;
931 	sdata->reserved_ready = false;
932 
933 	return 0;
934 }
935 
936 static void
937 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
938 {
939 	switch (sdata->vif.type) {
940 	case NL80211_IFTYPE_ADHOC:
941 	case NL80211_IFTYPE_AP:
942 	case NL80211_IFTYPE_MESH_POINT:
943 	case NL80211_IFTYPE_OCB:
944 		ieee80211_queue_work(&sdata->local->hw,
945 				     &sdata->csa_finalize_work);
946 		break;
947 	case NL80211_IFTYPE_STATION:
948 		ieee80211_queue_work(&sdata->local->hw,
949 				     &sdata->u.mgd.chswitch_work);
950 		break;
951 	case NL80211_IFTYPE_UNSPECIFIED:
952 	case NL80211_IFTYPE_AP_VLAN:
953 	case NL80211_IFTYPE_WDS:
954 	case NL80211_IFTYPE_MONITOR:
955 	case NL80211_IFTYPE_P2P_CLIENT:
956 	case NL80211_IFTYPE_P2P_GO:
957 	case NL80211_IFTYPE_P2P_DEVICE:
958 	case NUM_NL80211_IFTYPES:
959 		WARN_ON(1);
960 		break;
961 	}
962 }
963 
964 static void
965 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
966 			     const struct cfg80211_chan_def *chandef)
967 {
968 	struct ieee80211_sub_if_data *vlan;
969 
970 	sdata->vif.bss_conf.chandef = *chandef;
971 
972 	if (sdata->vif.type != NL80211_IFTYPE_AP)
973 		return;
974 
975 	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
976 		vlan->vif.bss_conf.chandef = *chandef;
977 }
978 
979 static int
980 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
981 {
982 	struct ieee80211_local *local = sdata->local;
983 	struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
984 	struct ieee80211_chanctx *old_ctx, *new_ctx;
985 	const struct cfg80211_chan_def *chandef;
986 	u32 changed = 0;
987 	int err;
988 
989 	lockdep_assert_held(&local->mtx);
990 	lockdep_assert_held(&local->chanctx_mtx);
991 
992 	new_ctx = sdata->reserved_chanctx;
993 	old_ctx = ieee80211_vif_get_chanctx(sdata);
994 
995 	if (WARN_ON(!sdata->reserved_ready))
996 		return -EBUSY;
997 
998 	if (WARN_ON(!new_ctx))
999 		return -EINVAL;
1000 
1001 	if (WARN_ON(!old_ctx))
1002 		return -EINVAL;
1003 
1004 	if (WARN_ON(new_ctx->replace_state ==
1005 		    IEEE80211_CHANCTX_REPLACES_OTHER))
1006 		return -EINVAL;
1007 
1008 	chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1009 				&sdata->reserved_chandef);
1010 	if (WARN_ON(!chandef))
1011 		return -EINVAL;
1012 
1013 	ieee80211_change_chanctx(local, new_ctx, chandef);
1014 
1015 	vif_chsw[0].vif = &sdata->vif;
1016 	vif_chsw[0].old_ctx = &old_ctx->conf;
1017 	vif_chsw[0].new_ctx = &new_ctx->conf;
1018 
1019 	list_del(&sdata->reserved_chanctx_list);
1020 	sdata->reserved_chanctx = NULL;
1021 
1022 	err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1023 				     CHANCTX_SWMODE_REASSIGN_VIF);
1024 	if (err) {
1025 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1026 			ieee80211_free_chanctx(local, new_ctx);
1027 
1028 		goto out;
1029 	}
1030 
1031 	list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1032 	rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1033 
1034 	if (sdata->vif.type == NL80211_IFTYPE_AP)
1035 		__ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1036 
1037 	ieee80211_check_fast_xmit_iface(sdata);
1038 
1039 	if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1040 		ieee80211_free_chanctx(local, old_ctx);
1041 
1042 	if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1043 		changed = BSS_CHANGED_BANDWIDTH;
1044 
1045 	ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1046 
1047 	ieee80211_recalc_smps_chanctx(local, new_ctx);
1048 	ieee80211_recalc_radar_chanctx(local, new_ctx);
1049 	ieee80211_recalc_chanctx_min_def(local, new_ctx);
1050 
1051 	if (changed)
1052 		ieee80211_bss_info_change_notify(sdata, changed);
1053 
1054 out:
1055 	ieee80211_vif_chanctx_reservation_complete(sdata);
1056 	return err;
1057 }
1058 
1059 static int
1060 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1061 {
1062 	struct ieee80211_local *local = sdata->local;
1063 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1064 	const struct cfg80211_chan_def *chandef;
1065 	int err;
1066 
1067 	old_ctx = ieee80211_vif_get_chanctx(sdata);
1068 	new_ctx = sdata->reserved_chanctx;
1069 
1070 	if (WARN_ON(!sdata->reserved_ready))
1071 		return -EINVAL;
1072 
1073 	if (WARN_ON(old_ctx))
1074 		return -EINVAL;
1075 
1076 	if (WARN_ON(!new_ctx))
1077 		return -EINVAL;
1078 
1079 	if (WARN_ON(new_ctx->replace_state ==
1080 		    IEEE80211_CHANCTX_REPLACES_OTHER))
1081 		return -EINVAL;
1082 
1083 	chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1084 				&sdata->reserved_chandef);
1085 	if (WARN_ON(!chandef))
1086 		return -EINVAL;
1087 
1088 	ieee80211_change_chanctx(local, new_ctx, chandef);
1089 
1090 	list_del(&sdata->reserved_chanctx_list);
1091 	sdata->reserved_chanctx = NULL;
1092 
1093 	err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1094 	if (err) {
1095 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1096 			ieee80211_free_chanctx(local, new_ctx);
1097 
1098 		goto out;
1099 	}
1100 
1101 out:
1102 	ieee80211_vif_chanctx_reservation_complete(sdata);
1103 	return err;
1104 }
1105 
1106 static bool
1107 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1108 {
1109 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1110 
1111 	lockdep_assert_held(&sdata->local->chanctx_mtx);
1112 
1113 	new_ctx = sdata->reserved_chanctx;
1114 	old_ctx = ieee80211_vif_get_chanctx(sdata);
1115 
1116 	if (!old_ctx)
1117 		return false;
1118 
1119 	if (WARN_ON(!new_ctx))
1120 		return false;
1121 
1122 	if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1123 		return false;
1124 
1125 	if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1126 		return false;
1127 
1128 	return true;
1129 }
1130 
1131 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1132 					struct ieee80211_chanctx *new_ctx)
1133 {
1134 	const struct cfg80211_chan_def *chandef;
1135 
1136 	lockdep_assert_held(&local->mtx);
1137 	lockdep_assert_held(&local->chanctx_mtx);
1138 
1139 	chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1140 	if (WARN_ON(!chandef))
1141 		return -EINVAL;
1142 
1143 	local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1144 	local->_oper_chandef = *chandef;
1145 	ieee80211_hw_config(local, 0);
1146 
1147 	return 0;
1148 }
1149 
1150 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1151 				      int n_vifs)
1152 {
1153 	struct ieee80211_vif_chanctx_switch *vif_chsw;
1154 	struct ieee80211_sub_if_data *sdata;
1155 	struct ieee80211_chanctx *ctx, *old_ctx;
1156 	int i, err;
1157 
1158 	lockdep_assert_held(&local->mtx);
1159 	lockdep_assert_held(&local->chanctx_mtx);
1160 
1161 	vif_chsw = kzalloc(sizeof(vif_chsw[0]) * n_vifs, GFP_KERNEL);
1162 	if (!vif_chsw)
1163 		return -ENOMEM;
1164 
1165 	i = 0;
1166 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1167 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1168 			continue;
1169 
1170 		if (WARN_ON(!ctx->replace_ctx)) {
1171 			err = -EINVAL;
1172 			goto out;
1173 		}
1174 
1175 		list_for_each_entry(sdata, &ctx->reserved_vifs,
1176 				    reserved_chanctx_list) {
1177 			if (!ieee80211_vif_has_in_place_reservation(
1178 					sdata))
1179 				continue;
1180 
1181 			old_ctx = ieee80211_vif_get_chanctx(sdata);
1182 			vif_chsw[i].vif = &sdata->vif;
1183 			vif_chsw[i].old_ctx = &old_ctx->conf;
1184 			vif_chsw[i].new_ctx = &ctx->conf;
1185 
1186 			i++;
1187 		}
1188 	}
1189 
1190 	err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1191 				     CHANCTX_SWMODE_SWAP_CONTEXTS);
1192 
1193 out:
1194 	kfree(vif_chsw);
1195 	return err;
1196 }
1197 
1198 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1199 {
1200 	struct ieee80211_chanctx *ctx;
1201 	int err;
1202 
1203 	lockdep_assert_held(&local->mtx);
1204 	lockdep_assert_held(&local->chanctx_mtx);
1205 
1206 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1207 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1208 			continue;
1209 
1210 		if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1211 			continue;
1212 
1213 		ieee80211_del_chanctx(local, ctx->replace_ctx);
1214 		err = ieee80211_add_chanctx(local, ctx);
1215 		if (err)
1216 			goto err;
1217 	}
1218 
1219 	return 0;
1220 
1221 err:
1222 	WARN_ON(ieee80211_add_chanctx(local, ctx));
1223 	list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1224 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1225 			continue;
1226 
1227 		if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1228 			continue;
1229 
1230 		ieee80211_del_chanctx(local, ctx);
1231 		WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1232 	}
1233 
1234 	return err;
1235 }
1236 
1237 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1238 {
1239 	struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1240 	struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1241 	struct ieee80211_chanctx *new_ctx = NULL;
1242 	int i, err, n_assigned, n_reserved, n_ready;
1243 	int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1244 
1245 	lockdep_assert_held(&local->mtx);
1246 	lockdep_assert_held(&local->chanctx_mtx);
1247 
1248 	/*
1249 	 * If there are 2 independent pairs of channel contexts performing
1250 	 * cross-switch of their vifs this code will still wait until both are
1251 	 * ready even though it could be possible to switch one before the
1252 	 * other is ready.
1253 	 *
1254 	 * For practical reasons and code simplicity just do a single huge
1255 	 * switch.
1256 	 */
1257 
1258 	/*
1259 	 * Verify if the reservation is still feasible.
1260 	 *  - if it's not then disconnect
1261 	 *  - if it is but not all vifs necessary are ready then defer
1262 	 */
1263 
1264 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1265 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1266 			continue;
1267 
1268 		if (WARN_ON(!ctx->replace_ctx)) {
1269 			err = -EINVAL;
1270 			goto err;
1271 		}
1272 
1273 		if (!local->use_chanctx)
1274 			new_ctx = ctx;
1275 
1276 		n_ctx++;
1277 
1278 		n_assigned = 0;
1279 		n_reserved = 0;
1280 		n_ready = 0;
1281 
1282 		list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1283 				    assigned_chanctx_list) {
1284 			n_assigned++;
1285 			if (sdata->reserved_chanctx) {
1286 				n_reserved++;
1287 				if (sdata->reserved_ready)
1288 					n_ready++;
1289 			}
1290 		}
1291 
1292 		if (n_assigned != n_reserved) {
1293 			if (n_ready == n_reserved) {
1294 				wiphy_info(local->hw.wiphy,
1295 					   "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1296 				err = -EBUSY;
1297 				goto err;
1298 			}
1299 
1300 			return -EAGAIN;
1301 		}
1302 
1303 		ctx->conf.radar_enabled = false;
1304 		list_for_each_entry(sdata, &ctx->reserved_vifs,
1305 				    reserved_chanctx_list) {
1306 			if (ieee80211_vif_has_in_place_reservation(sdata) &&
1307 			    !sdata->reserved_ready)
1308 				return -EAGAIN;
1309 
1310 			old_ctx = ieee80211_vif_get_chanctx(sdata);
1311 			if (old_ctx) {
1312 				if (old_ctx->replace_state ==
1313 				    IEEE80211_CHANCTX_WILL_BE_REPLACED)
1314 					n_vifs_switch++;
1315 				else
1316 					n_vifs_assign++;
1317 			} else {
1318 				n_vifs_ctxless++;
1319 			}
1320 
1321 			if (sdata->reserved_radar_required)
1322 				ctx->conf.radar_enabled = true;
1323 		}
1324 	}
1325 
1326 	if (WARN_ON(n_ctx == 0) ||
1327 	    WARN_ON(n_vifs_switch == 0 &&
1328 		    n_vifs_assign == 0 &&
1329 		    n_vifs_ctxless == 0) ||
1330 	    WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1331 	    WARN_ON(!new_ctx && !local->use_chanctx)) {
1332 		err = -EINVAL;
1333 		goto err;
1334 	}
1335 
1336 	/*
1337 	 * All necessary vifs are ready. Perform the switch now depending on
1338 	 * reservations and driver capabilities.
1339 	 */
1340 
1341 	if (local->use_chanctx) {
1342 		if (n_vifs_switch > 0) {
1343 			err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1344 			if (err)
1345 				goto err;
1346 		}
1347 
1348 		if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1349 			err = ieee80211_chsw_switch_ctxs(local);
1350 			if (err)
1351 				goto err;
1352 		}
1353 	} else {
1354 		err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1355 		if (err)
1356 			goto err;
1357 	}
1358 
1359 	/*
1360 	 * Update all structures, values and pointers to point to new channel
1361 	 * context(s).
1362 	 */
1363 
1364 	i = 0;
1365 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1366 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1367 			continue;
1368 
1369 		if (WARN_ON(!ctx->replace_ctx)) {
1370 			err = -EINVAL;
1371 			goto err;
1372 		}
1373 
1374 		list_for_each_entry(sdata, &ctx->reserved_vifs,
1375 				    reserved_chanctx_list) {
1376 			u32 changed = 0;
1377 
1378 			if (!ieee80211_vif_has_in_place_reservation(sdata))
1379 				continue;
1380 
1381 			rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1382 
1383 			if (sdata->vif.type == NL80211_IFTYPE_AP)
1384 				__ieee80211_vif_copy_chanctx_to_vlans(sdata,
1385 								      false);
1386 
1387 			ieee80211_check_fast_xmit_iface(sdata);
1388 
1389 			sdata->radar_required = sdata->reserved_radar_required;
1390 
1391 			if (sdata->vif.bss_conf.chandef.width !=
1392 			    sdata->reserved_chandef.width)
1393 				changed = BSS_CHANGED_BANDWIDTH;
1394 
1395 			ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1396 			if (changed)
1397 				ieee80211_bss_info_change_notify(sdata,
1398 								 changed);
1399 
1400 			ieee80211_recalc_txpower(sdata, false);
1401 		}
1402 
1403 		ieee80211_recalc_chanctx_chantype(local, ctx);
1404 		ieee80211_recalc_smps_chanctx(local, ctx);
1405 		ieee80211_recalc_radar_chanctx(local, ctx);
1406 		ieee80211_recalc_chanctx_min_def(local, ctx);
1407 
1408 		list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1409 					 reserved_chanctx_list) {
1410 			if (ieee80211_vif_get_chanctx(sdata) != ctx)
1411 				continue;
1412 
1413 			list_del(&sdata->reserved_chanctx_list);
1414 			list_move(&sdata->assigned_chanctx_list,
1415 				  &ctx->assigned_vifs);
1416 			sdata->reserved_chanctx = NULL;
1417 
1418 			ieee80211_vif_chanctx_reservation_complete(sdata);
1419 		}
1420 
1421 		/*
1422 		 * This context might have been a dependency for an already
1423 		 * ready re-assign reservation interface that was deferred. Do
1424 		 * not propagate error to the caller though. The in-place
1425 		 * reservation for originally requested interface has already
1426 		 * succeeded at this point.
1427 		 */
1428 		list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1429 					 reserved_chanctx_list) {
1430 			if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1431 					sdata)))
1432 				continue;
1433 
1434 			if (WARN_ON(sdata->reserved_chanctx != ctx))
1435 				continue;
1436 
1437 			if (!sdata->reserved_ready)
1438 				continue;
1439 
1440 			if (ieee80211_vif_get_chanctx(sdata))
1441 				err = ieee80211_vif_use_reserved_reassign(
1442 						sdata);
1443 			else
1444 				err = ieee80211_vif_use_reserved_assign(sdata);
1445 
1446 			if (err) {
1447 				sdata_info(sdata,
1448 					   "failed to finalize (re-)assign reservation (err=%d)\n",
1449 					   err);
1450 				ieee80211_vif_unreserve_chanctx(sdata);
1451 				cfg80211_stop_iface(local->hw.wiphy,
1452 						    &sdata->wdev,
1453 						    GFP_KERNEL);
1454 			}
1455 		}
1456 	}
1457 
1458 	/*
1459 	 * Finally free old contexts
1460 	 */
1461 
1462 	list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1463 		if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1464 			continue;
1465 
1466 		ctx->replace_ctx->replace_ctx = NULL;
1467 		ctx->replace_ctx->replace_state =
1468 				IEEE80211_CHANCTX_REPLACE_NONE;
1469 
1470 		list_del_rcu(&ctx->list);
1471 		kfree_rcu(ctx, rcu_head);
1472 	}
1473 
1474 	return 0;
1475 
1476 err:
1477 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1478 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1479 			continue;
1480 
1481 		list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1482 					 reserved_chanctx_list) {
1483 			ieee80211_vif_unreserve_chanctx(sdata);
1484 			ieee80211_vif_chanctx_reservation_complete(sdata);
1485 		}
1486 	}
1487 
1488 	return err;
1489 }
1490 
1491 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1492 {
1493 	struct ieee80211_local *local = sdata->local;
1494 	struct ieee80211_chanctx_conf *conf;
1495 	struct ieee80211_chanctx *ctx;
1496 	bool use_reserved_switch = false;
1497 
1498 	lockdep_assert_held(&local->chanctx_mtx);
1499 
1500 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1501 					 lockdep_is_held(&local->chanctx_mtx));
1502 	if (!conf)
1503 		return;
1504 
1505 	ctx = container_of(conf, struct ieee80211_chanctx, conf);
1506 
1507 	if (sdata->reserved_chanctx) {
1508 		if (sdata->reserved_chanctx->replace_state ==
1509 		    IEEE80211_CHANCTX_REPLACES_OTHER &&
1510 		    ieee80211_chanctx_num_reserved(local,
1511 						   sdata->reserved_chanctx) > 1)
1512 			use_reserved_switch = true;
1513 
1514 		ieee80211_vif_unreserve_chanctx(sdata);
1515 	}
1516 
1517 	ieee80211_assign_vif_chanctx(sdata, NULL);
1518 	if (ieee80211_chanctx_refcount(local, ctx) == 0)
1519 		ieee80211_free_chanctx(local, ctx);
1520 
1521 	sdata->radar_required = false;
1522 
1523 	/* Unreserving may ready an in-place reservation. */
1524 	if (use_reserved_switch)
1525 		ieee80211_vif_use_reserved_switch(local);
1526 }
1527 
1528 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1529 			      const struct cfg80211_chan_def *chandef,
1530 			      enum ieee80211_chanctx_mode mode)
1531 {
1532 	struct ieee80211_local *local = sdata->local;
1533 	struct ieee80211_chanctx *ctx;
1534 	u8 radar_detect_width = 0;
1535 	int ret;
1536 
1537 	lockdep_assert_held(&local->mtx);
1538 
1539 	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1540 
1541 	mutex_lock(&local->chanctx_mtx);
1542 
1543 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1544 					    chandef,
1545 					    sdata->wdev.iftype);
1546 	if (ret < 0)
1547 		goto out;
1548 	if (ret > 0)
1549 		radar_detect_width = BIT(chandef->width);
1550 
1551 	sdata->radar_required = ret;
1552 
1553 	ret = ieee80211_check_combinations(sdata, chandef, mode,
1554 					   radar_detect_width);
1555 	if (ret < 0)
1556 		goto out;
1557 
1558 	__ieee80211_vif_release_channel(sdata);
1559 
1560 	ctx = ieee80211_find_chanctx(local, chandef, mode);
1561 	if (!ctx)
1562 		ctx = ieee80211_new_chanctx(local, chandef, mode);
1563 	if (IS_ERR(ctx)) {
1564 		ret = PTR_ERR(ctx);
1565 		goto out;
1566 	}
1567 
1568 	ieee80211_vif_update_chandef(sdata, chandef);
1569 
1570 	ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1571 	if (ret) {
1572 		/* if assign fails refcount stays the same */
1573 		if (ieee80211_chanctx_refcount(local, ctx) == 0)
1574 			ieee80211_free_chanctx(local, ctx);
1575 		goto out;
1576 	}
1577 
1578 	ieee80211_recalc_smps_chanctx(local, ctx);
1579 	ieee80211_recalc_radar_chanctx(local, ctx);
1580  out:
1581 	if (ret)
1582 		sdata->radar_required = false;
1583 
1584 	mutex_unlock(&local->chanctx_mtx);
1585 	return ret;
1586 }
1587 
1588 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1589 {
1590 	struct ieee80211_local *local = sdata->local;
1591 	struct ieee80211_chanctx *new_ctx;
1592 	struct ieee80211_chanctx *old_ctx;
1593 	int err;
1594 
1595 	lockdep_assert_held(&local->mtx);
1596 	lockdep_assert_held(&local->chanctx_mtx);
1597 
1598 	new_ctx = sdata->reserved_chanctx;
1599 	old_ctx = ieee80211_vif_get_chanctx(sdata);
1600 
1601 	if (WARN_ON(!new_ctx))
1602 		return -EINVAL;
1603 
1604 	if (WARN_ON(new_ctx->replace_state ==
1605 		    IEEE80211_CHANCTX_WILL_BE_REPLACED))
1606 		return -EINVAL;
1607 
1608 	if (WARN_ON(sdata->reserved_ready))
1609 		return -EINVAL;
1610 
1611 	sdata->reserved_ready = true;
1612 
1613 	if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1614 		if (old_ctx)
1615 			err = ieee80211_vif_use_reserved_reassign(sdata);
1616 		else
1617 			err = ieee80211_vif_use_reserved_assign(sdata);
1618 
1619 		if (err)
1620 			return err;
1621 	}
1622 
1623 	/*
1624 	 * In-place reservation may need to be finalized now either if:
1625 	 *  a) sdata is taking part in the swapping itself and is the last one
1626 	 *  b) sdata has switched with a re-assign reservation to an existing
1627 	 *     context readying in-place switching of old_ctx
1628 	 *
1629 	 * In case of (b) do not propagate the error up because the requested
1630 	 * sdata already switched successfully. Just spill an extra warning.
1631 	 * The ieee80211_vif_use_reserved_switch() already stops all necessary
1632 	 * interfaces upon failure.
1633 	 */
1634 	if ((old_ctx &&
1635 	     old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1636 	    new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1637 		err = ieee80211_vif_use_reserved_switch(local);
1638 		if (err && err != -EAGAIN) {
1639 			if (new_ctx->replace_state ==
1640 			    IEEE80211_CHANCTX_REPLACES_OTHER)
1641 				return err;
1642 
1643 			wiphy_info(local->hw.wiphy,
1644 				   "depending in-place reservation failed (err=%d)\n",
1645 				   err);
1646 		}
1647 	}
1648 
1649 	return 0;
1650 }
1651 
1652 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1653 				   const struct cfg80211_chan_def *chandef,
1654 				   u32 *changed)
1655 {
1656 	struct ieee80211_local *local = sdata->local;
1657 	struct ieee80211_chanctx_conf *conf;
1658 	struct ieee80211_chanctx *ctx;
1659 	const struct cfg80211_chan_def *compat;
1660 	int ret;
1661 
1662 	if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1663 				     IEEE80211_CHAN_DISABLED))
1664 		return -EINVAL;
1665 
1666 	mutex_lock(&local->chanctx_mtx);
1667 	if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1668 		ret = 0;
1669 		goto out;
1670 	}
1671 
1672 	if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1673 	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1674 		ret = -EINVAL;
1675 		goto out;
1676 	}
1677 
1678 	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1679 					 lockdep_is_held(&local->chanctx_mtx));
1680 	if (!conf) {
1681 		ret = -EINVAL;
1682 		goto out;
1683 	}
1684 
1685 	ctx = container_of(conf, struct ieee80211_chanctx, conf);
1686 
1687 	compat = cfg80211_chandef_compatible(&conf->def, chandef);
1688 	if (!compat) {
1689 		ret = -EINVAL;
1690 		goto out;
1691 	}
1692 
1693 	switch (ctx->replace_state) {
1694 	case IEEE80211_CHANCTX_REPLACE_NONE:
1695 		if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1696 			ret = -EBUSY;
1697 			goto out;
1698 		}
1699 		break;
1700 	case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1701 		/* TODO: Perhaps the bandwidth change could be treated as a
1702 		 * reservation itself? */
1703 		ret = -EBUSY;
1704 		goto out;
1705 	case IEEE80211_CHANCTX_REPLACES_OTHER:
1706 		/* channel context that is going to replace another channel
1707 		 * context doesn't really exist and shouldn't be assigned
1708 		 * anywhere yet */
1709 		WARN_ON(1);
1710 		break;
1711 	}
1712 
1713 	ieee80211_vif_update_chandef(sdata, chandef);
1714 
1715 	ieee80211_recalc_chanctx_chantype(local, ctx);
1716 
1717 	*changed |= BSS_CHANGED_BANDWIDTH;
1718 	ret = 0;
1719  out:
1720 	mutex_unlock(&local->chanctx_mtx);
1721 	return ret;
1722 }
1723 
1724 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1725 {
1726 	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1727 
1728 	lockdep_assert_held(&sdata->local->mtx);
1729 
1730 	mutex_lock(&sdata->local->chanctx_mtx);
1731 	__ieee80211_vif_release_channel(sdata);
1732 	mutex_unlock(&sdata->local->chanctx_mtx);
1733 }
1734 
1735 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1736 {
1737 	struct ieee80211_local *local = sdata->local;
1738 	struct ieee80211_sub_if_data *ap;
1739 	struct ieee80211_chanctx_conf *conf;
1740 
1741 	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1742 		return;
1743 
1744 	ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1745 
1746 	mutex_lock(&local->chanctx_mtx);
1747 
1748 	conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1749 					 lockdep_is_held(&local->chanctx_mtx));
1750 	rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1751 	mutex_unlock(&local->chanctx_mtx);
1752 }
1753 
1754 void ieee80211_iter_chan_contexts_atomic(
1755 	struct ieee80211_hw *hw,
1756 	void (*iter)(struct ieee80211_hw *hw,
1757 		     struct ieee80211_chanctx_conf *chanctx_conf,
1758 		     void *data),
1759 	void *iter_data)
1760 {
1761 	struct ieee80211_local *local = hw_to_local(hw);
1762 	struct ieee80211_chanctx *ctx;
1763 
1764 	rcu_read_lock();
1765 	list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1766 		if (ctx->driver_present)
1767 			iter(hw, &ctx->conf, iter_data);
1768 	rcu_read_unlock();
1769 }
1770 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);
1771