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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * mac80211 - channel management
4  * Copyright 2020 - 2024 Intel Corporation
5  */
6 
7 #include <linux/nl80211.h>
8 #include <linux/export.h>
9 #include <linux/rtnetlink.h>
10 #include <net/cfg80211.h>
11 #include "ieee80211_i.h"
12 #include "driver-ops.h"
13 #include "rate.h"
14 
ieee80211_chanctx_num_assigned(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)15 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
16 					  struct ieee80211_chanctx *ctx)
17 {
18 	struct ieee80211_link_data *link;
19 	int num = 0;
20 
21 	lockdep_assert_wiphy(local->hw.wiphy);
22 
23 	list_for_each_entry(link, &ctx->assigned_links, assigned_chanctx_list)
24 		num++;
25 
26 	return num;
27 }
28 
ieee80211_chanctx_num_reserved(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)29 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
30 					  struct ieee80211_chanctx *ctx)
31 {
32 	struct ieee80211_link_data *link;
33 	int num = 0;
34 
35 	lockdep_assert_wiphy(local->hw.wiphy);
36 
37 	list_for_each_entry(link, &ctx->reserved_links, reserved_chanctx_list)
38 		num++;
39 
40 	return num;
41 }
42 
ieee80211_chanctx_refcount(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)43 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
44 			       struct ieee80211_chanctx *ctx)
45 {
46 	return ieee80211_chanctx_num_assigned(local, ctx) +
47 	       ieee80211_chanctx_num_reserved(local, ctx);
48 }
49 
ieee80211_num_chanctx(struct ieee80211_local * local,int radio_idx)50 static int ieee80211_num_chanctx(struct ieee80211_local *local, int radio_idx)
51 {
52 	struct ieee80211_chanctx *ctx;
53 	int num = 0;
54 
55 	lockdep_assert_wiphy(local->hw.wiphy);
56 
57 	list_for_each_entry(ctx, &local->chanctx_list, list) {
58 		if (radio_idx >= 0 && ctx->conf.radio_idx != radio_idx)
59 			continue;
60 		num++;
61 	}
62 
63 	return num;
64 }
65 
ieee80211_can_create_new_chanctx(struct ieee80211_local * local,int radio_idx)66 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local,
67 					     int radio_idx)
68 {
69 	lockdep_assert_wiphy(local->hw.wiphy);
70 
71 	return ieee80211_num_chanctx(local, radio_idx) <
72 	       ieee80211_max_num_channels(local, radio_idx);
73 }
74 
75 static struct ieee80211_chanctx *
ieee80211_link_get_chanctx(struct ieee80211_link_data * link)76 ieee80211_link_get_chanctx(struct ieee80211_link_data *link)
77 {
78 	struct ieee80211_local *local __maybe_unused = link->sdata->local;
79 	struct ieee80211_chanctx_conf *conf;
80 
81 	conf = rcu_dereference_protected(link->conf->chanctx_conf,
82 					 lockdep_is_held(&local->hw.wiphy->mtx));
83 	if (!conf)
84 		return NULL;
85 
86 	return container_of(conf, struct ieee80211_chanctx, conf);
87 }
88 
ieee80211_chanreq_identical(const struct ieee80211_chan_req * a,const struct ieee80211_chan_req * b)89 bool ieee80211_chanreq_identical(const struct ieee80211_chan_req *a,
90 				 const struct ieee80211_chan_req *b)
91 {
92 	if (!cfg80211_chandef_identical(&a->oper, &b->oper))
93 		return false;
94 	if (!a->ap.chan && !b->ap.chan)
95 		return true;
96 	return cfg80211_chandef_identical(&a->ap, &b->ap);
97 }
98 
99 static const struct ieee80211_chan_req *
ieee80211_chanreq_compatible(const struct ieee80211_chan_req * a,const struct ieee80211_chan_req * b,struct ieee80211_chan_req * tmp)100 ieee80211_chanreq_compatible(const struct ieee80211_chan_req *a,
101 			     const struct ieee80211_chan_req *b,
102 			     struct ieee80211_chan_req *tmp)
103 {
104 	const struct cfg80211_chan_def *compat;
105 
106 	if (a->ap.chan && b->ap.chan &&
107 	    !cfg80211_chandef_identical(&a->ap, &b->ap))
108 		return NULL;
109 
110 	compat = cfg80211_chandef_compatible(&a->oper, &b->oper);
111 	if (!compat)
112 		return NULL;
113 
114 	/* Note: later code assumes this always fills & returns tmp if compat */
115 	tmp->oper = *compat;
116 	tmp->ap = a->ap.chan ? a->ap : b->ap;
117 	return tmp;
118 }
119 
120 static const struct ieee80211_chan_req *
ieee80211_chanctx_compatible(struct ieee80211_chanctx * ctx,const struct ieee80211_chan_req * req,struct ieee80211_chan_req * tmp)121 ieee80211_chanctx_compatible(struct ieee80211_chanctx *ctx,
122 			     const struct ieee80211_chan_req *req,
123 			     struct ieee80211_chan_req *tmp)
124 {
125 	const struct ieee80211_chan_req *ret;
126 	struct ieee80211_chan_req tmp2;
127 
128 	*tmp = (struct ieee80211_chan_req){
129 		.oper = ctx->conf.def,
130 		.ap = ctx->conf.ap,
131 	};
132 
133 	ret = ieee80211_chanreq_compatible(tmp, req, &tmp2);
134 	if (!ret)
135 		return NULL;
136 	*tmp = *ret;
137 	return tmp;
138 }
139 
140 static const struct ieee80211_chan_req *
ieee80211_chanctx_reserved_chanreq(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,const struct ieee80211_chan_req * req,struct ieee80211_chan_req * tmp)141 ieee80211_chanctx_reserved_chanreq(struct ieee80211_local *local,
142 				   struct ieee80211_chanctx *ctx,
143 				   const struct ieee80211_chan_req *req,
144 				   struct ieee80211_chan_req *tmp)
145 {
146 	struct ieee80211_link_data *link;
147 
148 	lockdep_assert_wiphy(local->hw.wiphy);
149 
150 	if (WARN_ON(!req))
151 		return NULL;
152 
153 	list_for_each_entry(link, &ctx->reserved_links, reserved_chanctx_list) {
154 		req = ieee80211_chanreq_compatible(&link->reserved, req, tmp);
155 		if (!req)
156 			break;
157 	}
158 
159 	return req;
160 }
161 
162 static const struct ieee80211_chan_req *
ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,const struct ieee80211_chan_req * compat,struct ieee80211_chan_req * tmp)163 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
164 				       struct ieee80211_chanctx *ctx,
165 				       const struct ieee80211_chan_req *compat,
166 				       struct ieee80211_chan_req *tmp)
167 {
168 	struct ieee80211_link_data *link;
169 	const struct ieee80211_chan_req *comp_def = compat;
170 
171 	lockdep_assert_wiphy(local->hw.wiphy);
172 
173 	list_for_each_entry(link, &ctx->assigned_links, assigned_chanctx_list) {
174 		struct ieee80211_bss_conf *link_conf = link->conf;
175 
176 		if (link->reserved_chanctx)
177 			continue;
178 
179 		comp_def = ieee80211_chanreq_compatible(&link_conf->chanreq,
180 							comp_def, tmp);
181 		if (!comp_def)
182 			break;
183 	}
184 
185 	return comp_def;
186 }
187 
188 static bool
ieee80211_chanctx_can_reserve(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,const struct ieee80211_chan_req * req)189 ieee80211_chanctx_can_reserve(struct ieee80211_local *local,
190 			      struct ieee80211_chanctx *ctx,
191 			      const struct ieee80211_chan_req *req)
192 {
193 	struct ieee80211_chan_req tmp;
194 
195 	lockdep_assert_wiphy(local->hw.wiphy);
196 
197 	if (!ieee80211_chanctx_reserved_chanreq(local, ctx, req, &tmp))
198 		return false;
199 
200 	if (!ieee80211_chanctx_non_reserved_chandef(local, ctx, req, &tmp))
201 		return false;
202 
203 	if (!list_empty(&ctx->reserved_links) &&
204 	    ieee80211_chanctx_reserved_chanreq(local, ctx, req, &tmp))
205 		return true;
206 
207 	return false;
208 }
209 
210 static struct ieee80211_chanctx *
ieee80211_find_reservation_chanctx(struct ieee80211_local * local,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode)211 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
212 				   const struct ieee80211_chan_req *chanreq,
213 				   enum ieee80211_chanctx_mode mode)
214 {
215 	struct ieee80211_chanctx *ctx;
216 
217 	lockdep_assert_wiphy(local->hw.wiphy);
218 
219 	if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
220 		return NULL;
221 
222 	list_for_each_entry(ctx, &local->chanctx_list, list) {
223 		if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
224 			continue;
225 
226 		if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
227 			continue;
228 
229 		if (!ieee80211_chanctx_can_reserve(local, ctx, chanreq))
230 			continue;
231 
232 		return ctx;
233 	}
234 
235 	return NULL;
236 }
237 
ieee80211_get_sta_bw(struct sta_info * sta,unsigned int link_id)238 static enum nl80211_chan_width ieee80211_get_sta_bw(struct sta_info *sta,
239 						    unsigned int link_id)
240 {
241 	enum ieee80211_sta_rx_bandwidth width;
242 	struct link_sta_info *link_sta;
243 
244 	link_sta = wiphy_dereference(sta->local->hw.wiphy, sta->link[link_id]);
245 
246 	/* no effect if this STA has no presence on this link */
247 	if (!link_sta)
248 		return NL80211_CHAN_WIDTH_20_NOHT;
249 
250 	width = ieee80211_sta_cap_rx_bw(link_sta);
251 
252 	switch (width) {
253 	case IEEE80211_STA_RX_BW_20:
254 		if (link_sta->pub->ht_cap.ht_supported)
255 			return NL80211_CHAN_WIDTH_20;
256 		else
257 			return NL80211_CHAN_WIDTH_20_NOHT;
258 	case IEEE80211_STA_RX_BW_40:
259 		return NL80211_CHAN_WIDTH_40;
260 	case IEEE80211_STA_RX_BW_80:
261 		return NL80211_CHAN_WIDTH_80;
262 	case IEEE80211_STA_RX_BW_160:
263 		/*
264 		 * This applied for both 160 and 80+80. since we use
265 		 * the returned value to consider degradation of
266 		 * ctx->conf.min_def, we have to make sure to take
267 		 * the bigger one (NL80211_CHAN_WIDTH_160).
268 		 * Otherwise we might try degrading even when not
269 		 * needed, as the max required sta_bw returned (80+80)
270 		 * might be smaller than the configured bw (160).
271 		 */
272 		return NL80211_CHAN_WIDTH_160;
273 	case IEEE80211_STA_RX_BW_320:
274 		return NL80211_CHAN_WIDTH_320;
275 	default:
276 		WARN_ON(1);
277 		return NL80211_CHAN_WIDTH_20;
278 	}
279 }
280 
281 static enum nl80211_chan_width
ieee80211_get_max_required_bw(struct ieee80211_link_data * link)282 ieee80211_get_max_required_bw(struct ieee80211_link_data *link)
283 {
284 	struct ieee80211_sub_if_data *sdata = link->sdata;
285 	unsigned int link_id = link->link_id;
286 	enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
287 	struct sta_info *sta;
288 
289 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
290 
291 	list_for_each_entry(sta, &sdata->local->sta_list, list) {
292 		if (sdata != sta->sdata &&
293 		    !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
294 			continue;
295 
296 		max_bw = max(max_bw, ieee80211_get_sta_bw(sta, link_id));
297 	}
298 
299 	return max_bw;
300 }
301 
302 static enum nl80211_chan_width
ieee80211_get_chanctx_max_required_bw(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_link_data * rsvd_for,bool check_reserved)303 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
304 				      struct ieee80211_chanctx *ctx,
305 				      struct ieee80211_link_data *rsvd_for,
306 				      bool check_reserved)
307 {
308 	struct ieee80211_sub_if_data *sdata;
309 	struct ieee80211_link_data *link;
310 	enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
311 
312 	if (WARN_ON(check_reserved && rsvd_for))
313 		return ctx->conf.def.width;
314 
315 	for_each_sdata_link(local, link) {
316 		enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
317 
318 		if (check_reserved) {
319 			if (link->reserved_chanctx != ctx)
320 				continue;
321 		} else if (link != rsvd_for &&
322 			   rcu_access_pointer(link->conf->chanctx_conf) != &ctx->conf)
323 			continue;
324 
325 		switch (link->sdata->vif.type) {
326 		case NL80211_IFTYPE_AP:
327 		case NL80211_IFTYPE_AP_VLAN:
328 			width = ieee80211_get_max_required_bw(link);
329 			break;
330 		case NL80211_IFTYPE_STATION:
331 			/*
332 			 * The ap's sta->bandwidth is not set yet at this
333 			 * point, so take the width from the chandef, but
334 			 * account also for TDLS peers
335 			 */
336 			width = max(link->conf->chanreq.oper.width,
337 				    ieee80211_get_max_required_bw(link));
338 			break;
339 		case NL80211_IFTYPE_P2P_DEVICE:
340 		case NL80211_IFTYPE_NAN:
341 			continue;
342 		case NL80211_IFTYPE_ADHOC:
343 		case NL80211_IFTYPE_MESH_POINT:
344 		case NL80211_IFTYPE_OCB:
345 			width = link->conf->chanreq.oper.width;
346 			break;
347 		case NL80211_IFTYPE_WDS:
348 		case NL80211_IFTYPE_UNSPECIFIED:
349 		case NUM_NL80211_IFTYPES:
350 		case NL80211_IFTYPE_MONITOR:
351 		case NL80211_IFTYPE_P2P_CLIENT:
352 		case NL80211_IFTYPE_P2P_GO:
353 			WARN_ON_ONCE(1);
354 		}
355 
356 		max_bw = max(max_bw, width);
357 	}
358 
359 	/* use the configured bandwidth in case of monitor interface */
360 	sdata = wiphy_dereference(local->hw.wiphy, local->monitor_sdata);
361 	if (sdata &&
362 	    rcu_access_pointer(sdata->vif.bss_conf.chanctx_conf) == &ctx->conf)
363 		max_bw = max(max_bw, ctx->conf.def.width);
364 
365 	return max_bw;
366 }
367 
368 /*
369  * recalc the min required chan width of the channel context, which is
370  * the max of min required widths of all the interfaces bound to this
371  * channel context.
372  */
373 static u32
_ieee80211_recalc_chanctx_min_def(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_link_data * rsvd_for,bool check_reserved)374 _ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
375 				  struct ieee80211_chanctx *ctx,
376 				  struct ieee80211_link_data *rsvd_for,
377 				  bool check_reserved)
378 {
379 	enum nl80211_chan_width max_bw;
380 	struct cfg80211_chan_def min_def;
381 
382 	lockdep_assert_wiphy(local->hw.wiphy);
383 
384 	/* don't optimize non-20MHz based and radar_enabled confs */
385 	if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
386 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
387 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_1 ||
388 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_2 ||
389 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_4 ||
390 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_8 ||
391 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_16 ||
392 	    ctx->conf.radar_enabled) {
393 		ctx->conf.min_def = ctx->conf.def;
394 		return 0;
395 	}
396 
397 	max_bw = ieee80211_get_chanctx_max_required_bw(local, ctx, rsvd_for,
398 						       check_reserved);
399 
400 	/* downgrade chandef up to max_bw */
401 	min_def = ctx->conf.def;
402 	while (min_def.width > max_bw)
403 		ieee80211_chandef_downgrade(&min_def, NULL);
404 
405 	if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
406 		return 0;
407 
408 	ctx->conf.min_def = min_def;
409 	if (!ctx->driver_present)
410 		return 0;
411 
412 	return IEEE80211_CHANCTX_CHANGE_MIN_WIDTH;
413 }
414 
ieee80211_chan_bw_change(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,bool reserved,bool narrowed)415 static void ieee80211_chan_bw_change(struct ieee80211_local *local,
416 				     struct ieee80211_chanctx *ctx,
417 				     bool reserved, bool narrowed)
418 {
419 	struct sta_info *sta;
420 	struct ieee80211_supported_band *sband =
421 		local->hw.wiphy->bands[ctx->conf.def.chan->band];
422 
423 	rcu_read_lock();
424 	list_for_each_entry_rcu(sta, &local->sta_list,
425 				list) {
426 		struct ieee80211_sub_if_data *sdata = sta->sdata;
427 		enum ieee80211_sta_rx_bandwidth new_sta_bw;
428 		unsigned int link_id;
429 
430 		if (!ieee80211_sdata_running(sta->sdata))
431 			continue;
432 
433 		for (link_id = 0; link_id < ARRAY_SIZE(sta->sdata->link); link_id++) {
434 			struct ieee80211_link_data *link =
435 				rcu_dereference(sdata->link[link_id]);
436 			struct ieee80211_bss_conf *link_conf;
437 			struct cfg80211_chan_def *new_chandef;
438 			struct link_sta_info *link_sta;
439 
440 			if (!link)
441 				continue;
442 
443 			link_conf = link->conf;
444 
445 			if (rcu_access_pointer(link_conf->chanctx_conf) != &ctx->conf)
446 				continue;
447 
448 			link_sta = rcu_dereference(sta->link[link_id]);
449 			if (!link_sta)
450 				continue;
451 
452 			if (reserved)
453 				new_chandef = &link->reserved.oper;
454 			else
455 				new_chandef = &link_conf->chanreq.oper;
456 
457 			new_sta_bw = _ieee80211_sta_cur_vht_bw(link_sta,
458 							       new_chandef);
459 
460 			/* nothing change */
461 			if (new_sta_bw == link_sta->pub->bandwidth)
462 				continue;
463 
464 			/* vif changed to narrow BW and narrow BW for station wasn't
465 			 * requested or vise versa */
466 			if ((new_sta_bw < link_sta->pub->bandwidth) == !narrowed)
467 				continue;
468 
469 			link_sta->pub->bandwidth = new_sta_bw;
470 			rate_control_rate_update(local, sband, sta, link_id,
471 						 IEEE80211_RC_BW_CHANGED);
472 		}
473 	}
474 	rcu_read_unlock();
475 }
476 
477 /*
478  * recalc the min required chan width of the channel context, which is
479  * the max of min required widths of all the interfaces bound to this
480  * channel context.
481  */
ieee80211_recalc_chanctx_min_def(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_link_data * rsvd_for,bool check_reserved)482 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
483 				      struct ieee80211_chanctx *ctx,
484 				      struct ieee80211_link_data *rsvd_for,
485 				      bool check_reserved)
486 {
487 	u32 changed = _ieee80211_recalc_chanctx_min_def(local, ctx, rsvd_for,
488 							check_reserved);
489 
490 	if (!changed)
491 		return;
492 
493 	/* check is BW narrowed */
494 	ieee80211_chan_bw_change(local, ctx, false, true);
495 
496 	drv_change_chanctx(local, ctx, changed);
497 
498 	/* check is BW wider */
499 	ieee80211_chan_bw_change(local, ctx, false, false);
500 }
501 
_ieee80211_change_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_chanctx * old_ctx,const struct ieee80211_chan_req * chanreq,struct ieee80211_link_data * rsvd_for)502 static void _ieee80211_change_chanctx(struct ieee80211_local *local,
503 				      struct ieee80211_chanctx *ctx,
504 				      struct ieee80211_chanctx *old_ctx,
505 				      const struct ieee80211_chan_req *chanreq,
506 				      struct ieee80211_link_data *rsvd_for)
507 {
508 	const struct cfg80211_chan_def *chandef = &chanreq->oper;
509 	struct ieee80211_chan_req ctx_req = {
510 		.oper = ctx->conf.def,
511 		.ap = ctx->conf.ap,
512 	};
513 	u32 changed = 0;
514 
515 	/* expected to handle only 20/40/80/160/320 channel widths */
516 	switch (chandef->width) {
517 	case NL80211_CHAN_WIDTH_20_NOHT:
518 	case NL80211_CHAN_WIDTH_20:
519 	case NL80211_CHAN_WIDTH_40:
520 	case NL80211_CHAN_WIDTH_80:
521 	case NL80211_CHAN_WIDTH_80P80:
522 	case NL80211_CHAN_WIDTH_160:
523 	case NL80211_CHAN_WIDTH_320:
524 		break;
525 	default:
526 		WARN_ON(1);
527 	}
528 
529 	/* Check maybe BW narrowed - we do this _before_ calling recalc_chanctx_min_def
530 	 * due to maybe not returning from it, e.g in case new context was added
531 	 * first time with all parameters up to date.
532 	 */
533 	ieee80211_chan_bw_change(local, old_ctx, false, true);
534 
535 	if (ieee80211_chanreq_identical(&ctx_req, chanreq)) {
536 		ieee80211_recalc_chanctx_min_def(local, ctx, rsvd_for, false);
537 		return;
538 	}
539 
540 	WARN_ON(ieee80211_chanctx_refcount(local, ctx) > 1 &&
541 		!cfg80211_chandef_compatible(&ctx->conf.def, &chanreq->oper));
542 
543 	ieee80211_remove_wbrf(local, &ctx->conf.def);
544 
545 	if (!cfg80211_chandef_identical(&ctx->conf.def, &chanreq->oper)) {
546 		if (ctx->conf.def.width != chanreq->oper.width)
547 			changed |= IEEE80211_CHANCTX_CHANGE_WIDTH;
548 		if (ctx->conf.def.punctured != chanreq->oper.punctured)
549 			changed |= IEEE80211_CHANCTX_CHANGE_PUNCTURING;
550 	}
551 	if (!cfg80211_chandef_identical(&ctx->conf.ap, &chanreq->ap))
552 		changed |= IEEE80211_CHANCTX_CHANGE_AP;
553 	ctx->conf.def = *chandef;
554 	ctx->conf.ap = chanreq->ap;
555 
556 	/* check if min chanctx also changed */
557 	changed |= _ieee80211_recalc_chanctx_min_def(local, ctx, rsvd_for, false);
558 
559 	ieee80211_add_wbrf(local, &ctx->conf.def);
560 
561 	drv_change_chanctx(local, ctx, changed);
562 
563 	/* check if BW is wider */
564 	ieee80211_chan_bw_change(local, old_ctx, false, false);
565 }
566 
ieee80211_change_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_chanctx * old_ctx,const struct ieee80211_chan_req * chanreq)567 static void ieee80211_change_chanctx(struct ieee80211_local *local,
568 				     struct ieee80211_chanctx *ctx,
569 				     struct ieee80211_chanctx *old_ctx,
570 				     const struct ieee80211_chan_req *chanreq)
571 {
572 	_ieee80211_change_chanctx(local, ctx, old_ctx, chanreq, NULL);
573 }
574 
575 /* Note: if successful, the returned chanctx is reserved for the link */
576 static struct ieee80211_chanctx *
ieee80211_find_chanctx(struct ieee80211_local * local,struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode)577 ieee80211_find_chanctx(struct ieee80211_local *local,
578 		       struct ieee80211_link_data *link,
579 		       const struct ieee80211_chan_req *chanreq,
580 		       enum ieee80211_chanctx_mode mode)
581 {
582 	struct ieee80211_chan_req tmp;
583 	struct ieee80211_chanctx *ctx;
584 
585 	lockdep_assert_wiphy(local->hw.wiphy);
586 
587 	if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
588 		return NULL;
589 
590 	if (WARN_ON(link->reserved_chanctx))
591 		return NULL;
592 
593 	list_for_each_entry(ctx, &local->chanctx_list, list) {
594 		const struct ieee80211_chan_req *compat;
595 
596 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
597 			continue;
598 
599 		if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
600 			continue;
601 
602 		compat = ieee80211_chanctx_compatible(ctx, chanreq, &tmp);
603 		if (!compat)
604 			continue;
605 
606 		compat = ieee80211_chanctx_reserved_chanreq(local, ctx,
607 							    compat, &tmp);
608 		if (!compat)
609 			continue;
610 
611 		/*
612 		 * Reserve the chanctx temporarily, as the driver might change
613 		 * active links during callbacks we make into it below and/or
614 		 * later during assignment, which could (otherwise) cause the
615 		 * context to actually be removed.
616 		 */
617 		link->reserved_chanctx = ctx;
618 		list_add(&link->reserved_chanctx_list,
619 			 &ctx->reserved_links);
620 
621 		ieee80211_change_chanctx(local, ctx, ctx, compat);
622 
623 		return ctx;
624 	}
625 
626 	return NULL;
627 }
628 
ieee80211_is_radar_required(struct ieee80211_local * local)629 bool ieee80211_is_radar_required(struct ieee80211_local *local)
630 {
631 	struct ieee80211_link_data *link;
632 
633 	lockdep_assert_wiphy(local->hw.wiphy);
634 
635 	for_each_sdata_link(local, link) {
636 		if (link->radar_required)
637 			return true;
638 	}
639 
640 	return false;
641 }
642 
643 static bool
ieee80211_chanctx_radar_required(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)644 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
645 				 struct ieee80211_chanctx *ctx)
646 {
647 	struct ieee80211_chanctx_conf *conf = &ctx->conf;
648 	struct ieee80211_link_data *link;
649 
650 	lockdep_assert_wiphy(local->hw.wiphy);
651 
652 	for_each_sdata_link(local, link) {
653 		if (rcu_access_pointer(link->conf->chanctx_conf) != conf)
654 			continue;
655 		if (!link->radar_required)
656 			continue;
657 		return true;
658 	}
659 
660 	return false;
661 }
662 
663 static struct ieee80211_chanctx *
ieee80211_alloc_chanctx(struct ieee80211_local * local,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode,int radio_idx)664 ieee80211_alloc_chanctx(struct ieee80211_local *local,
665 			const struct ieee80211_chan_req *chanreq,
666 			enum ieee80211_chanctx_mode mode,
667 			int radio_idx)
668 {
669 	struct ieee80211_chanctx *ctx;
670 
671 	lockdep_assert_wiphy(local->hw.wiphy);
672 
673 	ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
674 	if (!ctx)
675 		return NULL;
676 
677 	INIT_LIST_HEAD(&ctx->assigned_links);
678 	INIT_LIST_HEAD(&ctx->reserved_links);
679 	ctx->conf.def = chanreq->oper;
680 	ctx->conf.ap = chanreq->ap;
681 	ctx->conf.rx_chains_static = 1;
682 	ctx->conf.rx_chains_dynamic = 1;
683 	ctx->mode = mode;
684 	ctx->conf.radar_enabled = false;
685 	ctx->conf.radio_idx = radio_idx;
686 	ctx->radar_detected = false;
687 	_ieee80211_recalc_chanctx_min_def(local, ctx, NULL, false);
688 
689 	return ctx;
690 }
691 
ieee80211_add_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)692 static int ieee80211_add_chanctx(struct ieee80211_local *local,
693 				 struct ieee80211_chanctx *ctx)
694 {
695 	u32 changed;
696 	int err;
697 
698 	lockdep_assert_wiphy(local->hw.wiphy);
699 
700 	ieee80211_add_wbrf(local, &ctx->conf.def);
701 
702 	/* turn idle off *before* setting channel -- some drivers need that */
703 	changed = ieee80211_idle_off(local);
704 	if (changed)
705 		ieee80211_hw_config(local, changed);
706 
707 	err = drv_add_chanctx(local, ctx);
708 	if (err) {
709 		ieee80211_recalc_idle(local);
710 		return err;
711 	}
712 
713 	return 0;
714 }
715 
716 static struct ieee80211_chanctx *
ieee80211_new_chanctx(struct ieee80211_local * local,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode,bool assign_on_failure,int radio_idx)717 ieee80211_new_chanctx(struct ieee80211_local *local,
718 		      const struct ieee80211_chan_req *chanreq,
719 		      enum ieee80211_chanctx_mode mode,
720 		      bool assign_on_failure,
721 		      int radio_idx)
722 {
723 	struct ieee80211_chanctx *ctx;
724 	int err;
725 
726 	lockdep_assert_wiphy(local->hw.wiphy);
727 
728 	ctx = ieee80211_alloc_chanctx(local, chanreq, mode, radio_idx);
729 	if (!ctx)
730 		return ERR_PTR(-ENOMEM);
731 
732 	err = ieee80211_add_chanctx(local, ctx);
733 	if (!assign_on_failure && err) {
734 		kfree(ctx);
735 		return ERR_PTR(err);
736 	}
737 	/* We ignored a driver error, see _ieee80211_set_active_links */
738 	WARN_ON_ONCE(err && !local->in_reconfig);
739 
740 	list_add_rcu(&ctx->list, &local->chanctx_list);
741 	return ctx;
742 }
743 
ieee80211_del_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,bool skip_idle_recalc)744 static void ieee80211_del_chanctx(struct ieee80211_local *local,
745 				  struct ieee80211_chanctx *ctx,
746 				  bool skip_idle_recalc)
747 {
748 	lockdep_assert_wiphy(local->hw.wiphy);
749 
750 	drv_remove_chanctx(local, ctx);
751 
752 	if (!skip_idle_recalc)
753 		ieee80211_recalc_idle(local);
754 
755 	ieee80211_remove_wbrf(local, &ctx->conf.def);
756 }
757 
ieee80211_free_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,bool skip_idle_recalc)758 static void ieee80211_free_chanctx(struct ieee80211_local *local,
759 				   struct ieee80211_chanctx *ctx,
760 				   bool skip_idle_recalc)
761 {
762 	lockdep_assert_wiphy(local->hw.wiphy);
763 
764 	WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
765 
766 	list_del_rcu(&ctx->list);
767 	ieee80211_del_chanctx(local, ctx, skip_idle_recalc);
768 	kfree_rcu(ctx, rcu_head);
769 }
770 
ieee80211_recalc_chanctx_chantype(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)771 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
772 				       struct ieee80211_chanctx *ctx)
773 {
774 	struct ieee80211_chanctx_conf *conf = &ctx->conf;
775 	const struct ieee80211_chan_req *compat = NULL;
776 	struct ieee80211_link_data *link;
777 	struct ieee80211_chan_req tmp;
778 	struct sta_info *sta;
779 
780 	lockdep_assert_wiphy(local->hw.wiphy);
781 
782 	for_each_sdata_link(local, link) {
783 		struct ieee80211_bss_conf *link_conf;
784 
785 		if (link->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
786 			continue;
787 
788 		link_conf = link->conf;
789 
790 		if (rcu_access_pointer(link_conf->chanctx_conf) != conf)
791 			continue;
792 
793 		if (!compat)
794 			compat = &link_conf->chanreq;
795 
796 		compat = ieee80211_chanreq_compatible(&link_conf->chanreq,
797 						      compat, &tmp);
798 		if (WARN_ON_ONCE(!compat))
799 			return;
800 	}
801 
802 	if (WARN_ON_ONCE(!compat))
803 		return;
804 
805 	/* TDLS peers can sometimes affect the chandef width */
806 	list_for_each_entry(sta, &local->sta_list, list) {
807 		struct ieee80211_sub_if_data *sdata = sta->sdata;
808 		struct ieee80211_chan_req tdls_chanreq = {};
809 		int tdls_link_id;
810 
811 		if (!sta->uploaded ||
812 		    !test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW) ||
813 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
814 		    !sta->tdls_chandef.chan)
815 			continue;
816 
817 		tdls_link_id = ieee80211_tdls_sta_link_id(sta);
818 		link = sdata_dereference(sdata->link[tdls_link_id], sdata);
819 		if (!link)
820 			continue;
821 
822 		if (rcu_access_pointer(link->conf->chanctx_conf) != conf)
823 			continue;
824 
825 		tdls_chanreq.oper = sta->tdls_chandef;
826 
827 		/* note this always fills and returns &tmp if compat */
828 		compat = ieee80211_chanreq_compatible(&tdls_chanreq,
829 						      compat, &tmp);
830 		if (WARN_ON_ONCE(!compat))
831 			return;
832 	}
833 
834 	ieee80211_change_chanctx(local, ctx, ctx, compat);
835 }
836 
ieee80211_recalc_radar_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * chanctx)837 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
838 					   struct ieee80211_chanctx *chanctx)
839 {
840 	bool radar_enabled;
841 
842 	lockdep_assert_wiphy(local->hw.wiphy);
843 
844 	radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
845 
846 	if (radar_enabled == chanctx->conf.radar_enabled)
847 		return;
848 
849 	chanctx->conf.radar_enabled = radar_enabled;
850 
851 	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
852 }
853 
ieee80211_assign_link_chanctx(struct ieee80211_link_data * link,struct ieee80211_chanctx * new_ctx,bool assign_on_failure)854 static int ieee80211_assign_link_chanctx(struct ieee80211_link_data *link,
855 					 struct ieee80211_chanctx *new_ctx,
856 					 bool assign_on_failure)
857 {
858 	struct ieee80211_sub_if_data *sdata = link->sdata;
859 	struct ieee80211_local *local = sdata->local;
860 	struct ieee80211_chanctx_conf *conf;
861 	struct ieee80211_chanctx *curr_ctx = NULL;
862 	bool new_idle;
863 	int ret;
864 
865 	if (WARN_ON(sdata->vif.type == NL80211_IFTYPE_NAN))
866 		return -EOPNOTSUPP;
867 
868 	conf = rcu_dereference_protected(link->conf->chanctx_conf,
869 					 lockdep_is_held(&local->hw.wiphy->mtx));
870 
871 	if (conf) {
872 		curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
873 
874 		drv_unassign_vif_chanctx(local, sdata, link->conf, curr_ctx);
875 		conf = NULL;
876 		list_del(&link->assigned_chanctx_list);
877 	}
878 
879 	if (new_ctx) {
880 		/* recalc considering the link we'll use it for now */
881 		ieee80211_recalc_chanctx_min_def(local, new_ctx, link, false);
882 
883 		ret = drv_assign_vif_chanctx(local, sdata, link->conf, new_ctx);
884 		if (assign_on_failure || !ret) {
885 			/* Need to continue, see _ieee80211_set_active_links */
886 			WARN_ON_ONCE(ret && !local->in_reconfig);
887 			ret = 0;
888 
889 			/* succeeded, so commit it to the data structures */
890 			conf = &new_ctx->conf;
891 			list_add(&link->assigned_chanctx_list,
892 				 &new_ctx->assigned_links);
893 		}
894 	} else {
895 		ret = 0;
896 	}
897 
898 	rcu_assign_pointer(link->conf->chanctx_conf, conf);
899 
900 	if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
901 		ieee80211_recalc_chanctx_chantype(local, curr_ctx);
902 		ieee80211_recalc_smps_chanctx(local, curr_ctx);
903 		ieee80211_recalc_radar_chanctx(local, curr_ctx);
904 		ieee80211_recalc_chanctx_min_def(local, curr_ctx, NULL, false);
905 	}
906 
907 	if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
908 		ieee80211_recalc_txpower(sdata, false);
909 		ieee80211_recalc_chanctx_min_def(local, new_ctx, NULL, false);
910 	}
911 
912 	if (conf) {
913 		new_idle = false;
914 	} else {
915 		struct ieee80211_link_data *tmp;
916 
917 		new_idle = true;
918 		for_each_sdata_link(local, tmp) {
919 			if (rcu_access_pointer(tmp->conf->chanctx_conf)) {
920 				new_idle = false;
921 				break;
922 			}
923 		}
924 	}
925 
926 	if (new_idle != sdata->vif.cfg.idle) {
927 		sdata->vif.cfg.idle = new_idle;
928 
929 		if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
930 		    sdata->vif.type != NL80211_IFTYPE_MONITOR)
931 			ieee80211_vif_cfg_change_notify(sdata, BSS_CHANGED_IDLE);
932 	}
933 
934 	ieee80211_check_fast_xmit_iface(sdata);
935 
936 	return ret;
937 }
938 
ieee80211_recalc_smps_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * chanctx)939 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
940 				   struct ieee80211_chanctx *chanctx)
941 {
942 	struct ieee80211_sub_if_data *sdata;
943 	u8 rx_chains_static, rx_chains_dynamic;
944 	struct ieee80211_link_data *link;
945 
946 	lockdep_assert_wiphy(local->hw.wiphy);
947 
948 	rx_chains_static = 1;
949 	rx_chains_dynamic = 1;
950 
951 	for_each_sdata_link(local, link) {
952 		u8 needed_static, needed_dynamic;
953 
954 		switch (link->sdata->vif.type) {
955 		case NL80211_IFTYPE_STATION:
956 			if (!link->sdata->u.mgd.associated)
957 				continue;
958 			break;
959 		case NL80211_IFTYPE_AP:
960 		case NL80211_IFTYPE_ADHOC:
961 		case NL80211_IFTYPE_MESH_POINT:
962 		case NL80211_IFTYPE_OCB:
963 			break;
964 		default:
965 			continue;
966 		}
967 
968 		if (rcu_access_pointer(link->conf->chanctx_conf) != &chanctx->conf)
969 			continue;
970 
971 		switch (link->smps_mode) {
972 		default:
973 			WARN_ONCE(1, "Invalid SMPS mode %d\n",
974 				  link->smps_mode);
975 			fallthrough;
976 		case IEEE80211_SMPS_OFF:
977 			needed_static = link->needed_rx_chains;
978 			needed_dynamic = link->needed_rx_chains;
979 			break;
980 		case IEEE80211_SMPS_DYNAMIC:
981 			needed_static = 1;
982 			needed_dynamic = link->needed_rx_chains;
983 			break;
984 		case IEEE80211_SMPS_STATIC:
985 			needed_static = 1;
986 			needed_dynamic = 1;
987 			break;
988 		}
989 
990 		rx_chains_static = max(rx_chains_static, needed_static);
991 		rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
992 	}
993 
994 	/* Disable SMPS for the monitor interface */
995 	sdata = wiphy_dereference(local->hw.wiphy, local->monitor_sdata);
996 	if (sdata &&
997 	    rcu_access_pointer(sdata->vif.bss_conf.chanctx_conf) == &chanctx->conf)
998 		rx_chains_dynamic = rx_chains_static = local->rx_chains;
999 
1000 	if (rx_chains_static == chanctx->conf.rx_chains_static &&
1001 	    rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
1002 		return;
1003 
1004 	chanctx->conf.rx_chains_static = rx_chains_static;
1005 	chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
1006 	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
1007 }
1008 
1009 static void
__ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data * link,bool clear)1010 __ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data *link,
1011 				       bool clear)
1012 {
1013 	struct ieee80211_sub_if_data *sdata = link->sdata;
1014 	unsigned int link_id = link->link_id;
1015 	struct ieee80211_bss_conf *link_conf = link->conf;
1016 	struct ieee80211_local *local __maybe_unused = sdata->local;
1017 	struct ieee80211_sub_if_data *vlan;
1018 	struct ieee80211_chanctx_conf *conf;
1019 
1020 	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
1021 		return;
1022 
1023 	lockdep_assert_wiphy(local->hw.wiphy);
1024 
1025 	/* Check that conf exists, even when clearing this function
1026 	 * must be called with the AP's channel context still there
1027 	 * as it would otherwise cause VLANs to have an invalid
1028 	 * channel context pointer for a while, possibly pointing
1029 	 * to a channel context that has already been freed.
1030 	 */
1031 	conf = rcu_dereference_protected(link_conf->chanctx_conf,
1032 					 lockdep_is_held(&local->hw.wiphy->mtx));
1033 	WARN_ON(!conf);
1034 
1035 	if (clear)
1036 		conf = NULL;
1037 
1038 	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
1039 		struct ieee80211_bss_conf *vlan_conf;
1040 
1041 		vlan_conf = wiphy_dereference(local->hw.wiphy,
1042 					      vlan->vif.link_conf[link_id]);
1043 		if (WARN_ON(!vlan_conf))
1044 			continue;
1045 
1046 		rcu_assign_pointer(vlan_conf->chanctx_conf, conf);
1047 	}
1048 }
1049 
ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data * link,bool clear)1050 void ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data *link,
1051 					  bool clear)
1052 {
1053 	struct ieee80211_local *local = link->sdata->local;
1054 
1055 	lockdep_assert_wiphy(local->hw.wiphy);
1056 
1057 	__ieee80211_link_copy_chanctx_to_vlans(link, clear);
1058 }
1059 
ieee80211_link_unreserve_chanctx(struct ieee80211_link_data * link)1060 int ieee80211_link_unreserve_chanctx(struct ieee80211_link_data *link)
1061 {
1062 	struct ieee80211_sub_if_data *sdata = link->sdata;
1063 	struct ieee80211_chanctx *ctx = link->reserved_chanctx;
1064 
1065 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1066 
1067 	if (WARN_ON(!ctx))
1068 		return -EINVAL;
1069 
1070 	list_del(&link->reserved_chanctx_list);
1071 	link->reserved_chanctx = NULL;
1072 
1073 	if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
1074 		if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1075 			if (WARN_ON(!ctx->replace_ctx))
1076 				return -EINVAL;
1077 
1078 			WARN_ON(ctx->replace_ctx->replace_state !=
1079 			        IEEE80211_CHANCTX_WILL_BE_REPLACED);
1080 			WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
1081 
1082 			ctx->replace_ctx->replace_ctx = NULL;
1083 			ctx->replace_ctx->replace_state =
1084 					IEEE80211_CHANCTX_REPLACE_NONE;
1085 
1086 			list_del_rcu(&ctx->list);
1087 			kfree_rcu(ctx, rcu_head);
1088 		} else {
1089 			ieee80211_free_chanctx(sdata->local, ctx, false);
1090 		}
1091 	}
1092 
1093 	return 0;
1094 }
1095 
1096 static struct ieee80211_chanctx *
ieee80211_replace_chanctx(struct ieee80211_local * local,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode,struct ieee80211_chanctx * curr_ctx)1097 ieee80211_replace_chanctx(struct ieee80211_local *local,
1098 			  const struct ieee80211_chan_req *chanreq,
1099 			  enum ieee80211_chanctx_mode mode,
1100 			  struct ieee80211_chanctx *curr_ctx)
1101 {
1102 	struct ieee80211_chanctx *new_ctx, *ctx;
1103 	struct wiphy *wiphy = local->hw.wiphy;
1104 	const struct wiphy_radio *radio;
1105 
1106 	if (!curr_ctx || (curr_ctx->replace_state ==
1107 			  IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1108 	    !list_empty(&curr_ctx->reserved_links)) {
1109 		/*
1110 		 * Another link already requested this context for a
1111 		 * reservation. Find another one hoping all links assigned
1112 		 * to it will also switch soon enough.
1113 		 *
1114 		 * TODO: This needs a little more work as some cases
1115 		 * (more than 2 chanctx capable devices) may fail which could
1116 		 * otherwise succeed provided some channel context juggling was
1117 		 * performed.
1118 		 *
1119 		 * Consider ctx1..3, link1..6, each ctx has 2 links. link1 and
1120 		 * link2 from ctx1 request new different chandefs starting 2
1121 		 * in-place reserations with ctx4 and ctx5 replacing ctx1 and
1122 		 * ctx2 respectively. Next link5 and link6 from ctx3 reserve
1123 		 * ctx4. If link3 and link4 remain on ctx2 as they are then this
1124 		 * fails unless `replace_ctx` from ctx5 is replaced with ctx3.
1125 		 */
1126 		list_for_each_entry(ctx, &local->chanctx_list, list) {
1127 			if (ctx->replace_state !=
1128 			    IEEE80211_CHANCTX_REPLACE_NONE)
1129 				continue;
1130 
1131 			if (!list_empty(&ctx->reserved_links))
1132 				continue;
1133 
1134 			if (ctx->conf.radio_idx >= 0) {
1135 				radio = &wiphy->radio[ctx->conf.radio_idx];
1136 				if (!cfg80211_radio_chandef_valid(radio, &chanreq->oper))
1137 					continue;
1138 			}
1139 
1140 			curr_ctx = ctx;
1141 			break;
1142 		}
1143 	}
1144 
1145 	/*
1146 	 * If that's true then all available contexts already have reservations
1147 	 * and cannot be used.
1148 	 */
1149 	if (!curr_ctx || (curr_ctx->replace_state ==
1150 			  IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1151 	    !list_empty(&curr_ctx->reserved_links))
1152 		return ERR_PTR(-EBUSY);
1153 
1154 	new_ctx = ieee80211_alloc_chanctx(local, chanreq, mode, -1);
1155 	if (!new_ctx)
1156 		return ERR_PTR(-ENOMEM);
1157 
1158 	new_ctx->replace_ctx = curr_ctx;
1159 	new_ctx->replace_state = IEEE80211_CHANCTX_REPLACES_OTHER;
1160 
1161 	curr_ctx->replace_ctx = new_ctx;
1162 	curr_ctx->replace_state = IEEE80211_CHANCTX_WILL_BE_REPLACED;
1163 
1164 	list_add_rcu(&new_ctx->list, &local->chanctx_list);
1165 
1166 	return new_ctx;
1167 }
1168 
1169 static bool
ieee80211_find_available_radio(struct ieee80211_local * local,const struct ieee80211_chan_req * chanreq,int * radio_idx)1170 ieee80211_find_available_radio(struct ieee80211_local *local,
1171 			       const struct ieee80211_chan_req *chanreq,
1172 			       int *radio_idx)
1173 {
1174 	struct wiphy *wiphy = local->hw.wiphy;
1175 	const struct wiphy_radio *radio;
1176 	int i;
1177 
1178 	*radio_idx = -1;
1179 	if (!wiphy->n_radio)
1180 		return true;
1181 
1182 	for (i = 0; i < wiphy->n_radio; i++) {
1183 		radio = &wiphy->radio[i];
1184 		if (!cfg80211_radio_chandef_valid(radio, &chanreq->oper))
1185 			continue;
1186 
1187 		if (!ieee80211_can_create_new_chanctx(local, i))
1188 			continue;
1189 
1190 		*radio_idx = i;
1191 		return true;
1192 	}
1193 
1194 	return false;
1195 }
1196 
ieee80211_link_reserve_chanctx(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode,bool radar_required)1197 int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
1198 				   const struct ieee80211_chan_req *chanreq,
1199 				   enum ieee80211_chanctx_mode mode,
1200 				   bool radar_required)
1201 {
1202 	struct ieee80211_sub_if_data *sdata = link->sdata;
1203 	struct ieee80211_local *local = sdata->local;
1204 	struct ieee80211_chanctx *new_ctx, *curr_ctx;
1205 	int radio_idx;
1206 
1207 	lockdep_assert_wiphy(local->hw.wiphy);
1208 
1209 	curr_ctx = ieee80211_link_get_chanctx(link);
1210 	if (curr_ctx && !local->ops->switch_vif_chanctx)
1211 		return -EOPNOTSUPP;
1212 
1213 	new_ctx = ieee80211_find_reservation_chanctx(local, chanreq, mode);
1214 	if (!new_ctx) {
1215 		if (ieee80211_can_create_new_chanctx(local, -1) &&
1216 		    ieee80211_find_available_radio(local, chanreq, &radio_idx))
1217 			new_ctx = ieee80211_new_chanctx(local, chanreq, mode,
1218 							false, radio_idx);
1219 		else
1220 			new_ctx = ieee80211_replace_chanctx(local, chanreq,
1221 							    mode, curr_ctx);
1222 		if (IS_ERR(new_ctx))
1223 			return PTR_ERR(new_ctx);
1224 	}
1225 
1226 	list_add(&link->reserved_chanctx_list, &new_ctx->reserved_links);
1227 	link->reserved_chanctx = new_ctx;
1228 	link->reserved = *chanreq;
1229 	link->reserved_radar_required = radar_required;
1230 	link->reserved_ready = false;
1231 
1232 	return 0;
1233 }
1234 
1235 static void
ieee80211_link_chanctx_reservation_complete(struct ieee80211_link_data * link)1236 ieee80211_link_chanctx_reservation_complete(struct ieee80211_link_data *link)
1237 {
1238 	struct ieee80211_sub_if_data *sdata = link->sdata;
1239 
1240 	switch (sdata->vif.type) {
1241 	case NL80211_IFTYPE_ADHOC:
1242 	case NL80211_IFTYPE_AP:
1243 	case NL80211_IFTYPE_MESH_POINT:
1244 	case NL80211_IFTYPE_OCB:
1245 		wiphy_work_queue(sdata->local->hw.wiphy,
1246 				 &link->csa.finalize_work);
1247 		break;
1248 	case NL80211_IFTYPE_STATION:
1249 		wiphy_delayed_work_queue(sdata->local->hw.wiphy,
1250 					 &link->u.mgd.csa.switch_work, 0);
1251 		break;
1252 	case NL80211_IFTYPE_UNSPECIFIED:
1253 	case NL80211_IFTYPE_AP_VLAN:
1254 	case NL80211_IFTYPE_WDS:
1255 	case NL80211_IFTYPE_MONITOR:
1256 	case NL80211_IFTYPE_P2P_CLIENT:
1257 	case NL80211_IFTYPE_P2P_GO:
1258 	case NL80211_IFTYPE_P2P_DEVICE:
1259 	case NL80211_IFTYPE_NAN:
1260 	case NUM_NL80211_IFTYPES:
1261 		WARN_ON(1);
1262 		break;
1263 	}
1264 }
1265 
1266 static void
ieee80211_link_update_chanreq(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq)1267 ieee80211_link_update_chanreq(struct ieee80211_link_data *link,
1268 			      const struct ieee80211_chan_req *chanreq)
1269 {
1270 	struct ieee80211_sub_if_data *sdata = link->sdata;
1271 	unsigned int link_id = link->link_id;
1272 	struct ieee80211_sub_if_data *vlan;
1273 
1274 	link->conf->chanreq = *chanreq;
1275 
1276 	if (sdata->vif.type != NL80211_IFTYPE_AP)
1277 		return;
1278 
1279 	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
1280 		struct ieee80211_bss_conf *vlan_conf;
1281 
1282 		vlan_conf = wiphy_dereference(sdata->local->hw.wiphy,
1283 					      vlan->vif.link_conf[link_id]);
1284 		if (WARN_ON(!vlan_conf))
1285 			continue;
1286 
1287 		vlan_conf->chanreq = *chanreq;
1288 	}
1289 }
1290 
1291 static int
ieee80211_link_use_reserved_reassign(struct ieee80211_link_data * link)1292 ieee80211_link_use_reserved_reassign(struct ieee80211_link_data *link)
1293 {
1294 	struct ieee80211_sub_if_data *sdata = link->sdata;
1295 	struct ieee80211_bss_conf *link_conf = link->conf;
1296 	struct ieee80211_local *local = sdata->local;
1297 	struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1298 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1299 	const struct ieee80211_chan_req *chanreq;
1300 	struct ieee80211_chan_req tmp;
1301 	u64 changed = 0;
1302 	int err;
1303 
1304 	lockdep_assert_wiphy(local->hw.wiphy);
1305 
1306 	new_ctx = link->reserved_chanctx;
1307 	old_ctx = ieee80211_link_get_chanctx(link);
1308 
1309 	if (WARN_ON(!link->reserved_ready))
1310 		return -EBUSY;
1311 
1312 	if (WARN_ON(!new_ctx))
1313 		return -EINVAL;
1314 
1315 	if (WARN_ON(!old_ctx))
1316 		return -EINVAL;
1317 
1318 	if (WARN_ON(new_ctx->replace_state ==
1319 		    IEEE80211_CHANCTX_REPLACES_OTHER))
1320 		return -EINVAL;
1321 
1322 	chanreq = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1323 							 &link->reserved,
1324 							 &tmp);
1325 	if (WARN_ON(!chanreq))
1326 		return -EINVAL;
1327 
1328 	if (link_conf->chanreq.oper.width != link->reserved.oper.width)
1329 		changed = BSS_CHANGED_BANDWIDTH;
1330 
1331 	ieee80211_link_update_chanreq(link, &link->reserved);
1332 
1333 	_ieee80211_change_chanctx(local, new_ctx, old_ctx, chanreq, link);
1334 
1335 	vif_chsw[0].vif = &sdata->vif;
1336 	vif_chsw[0].old_ctx = &old_ctx->conf;
1337 	vif_chsw[0].new_ctx = &new_ctx->conf;
1338 	vif_chsw[0].link_conf = link->conf;
1339 
1340 	list_del(&link->reserved_chanctx_list);
1341 	link->reserved_chanctx = NULL;
1342 
1343 	err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1344 				     CHANCTX_SWMODE_REASSIGN_VIF);
1345 	if (err) {
1346 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1347 			ieee80211_free_chanctx(local, new_ctx, false);
1348 
1349 		goto out;
1350 	}
1351 
1352 	link->radar_required = link->reserved_radar_required;
1353 	list_move(&link->assigned_chanctx_list, &new_ctx->assigned_links);
1354 	rcu_assign_pointer(link_conf->chanctx_conf, &new_ctx->conf);
1355 
1356 	if (sdata->vif.type == NL80211_IFTYPE_AP)
1357 		__ieee80211_link_copy_chanctx_to_vlans(link, false);
1358 
1359 	ieee80211_check_fast_xmit_iface(sdata);
1360 
1361 	if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1362 		ieee80211_free_chanctx(local, old_ctx, false);
1363 
1364 	ieee80211_recalc_chanctx_min_def(local, new_ctx, NULL, false);
1365 	ieee80211_recalc_smps_chanctx(local, new_ctx);
1366 	ieee80211_recalc_radar_chanctx(local, new_ctx);
1367 
1368 	if (changed)
1369 		ieee80211_link_info_change_notify(sdata, link, changed);
1370 
1371 out:
1372 	ieee80211_link_chanctx_reservation_complete(link);
1373 	return err;
1374 }
1375 
1376 static int
ieee80211_link_use_reserved_assign(struct ieee80211_link_data * link)1377 ieee80211_link_use_reserved_assign(struct ieee80211_link_data *link)
1378 {
1379 	struct ieee80211_sub_if_data *sdata = link->sdata;
1380 	struct ieee80211_local *local = sdata->local;
1381 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1382 	const struct ieee80211_chan_req *chanreq;
1383 	struct ieee80211_chan_req tmp;
1384 	int err;
1385 
1386 	old_ctx = ieee80211_link_get_chanctx(link);
1387 	new_ctx = link->reserved_chanctx;
1388 
1389 	if (WARN_ON(!link->reserved_ready))
1390 		return -EINVAL;
1391 
1392 	if (WARN_ON(old_ctx))
1393 		return -EINVAL;
1394 
1395 	if (WARN_ON(!new_ctx))
1396 		return -EINVAL;
1397 
1398 	if (WARN_ON(new_ctx->replace_state ==
1399 		    IEEE80211_CHANCTX_REPLACES_OTHER))
1400 		return -EINVAL;
1401 
1402 	chanreq = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1403 							 &link->reserved,
1404 							 &tmp);
1405 	if (WARN_ON(!chanreq))
1406 		return -EINVAL;
1407 
1408 	ieee80211_change_chanctx(local, new_ctx, new_ctx, chanreq);
1409 
1410 	list_del(&link->reserved_chanctx_list);
1411 	link->reserved_chanctx = NULL;
1412 
1413 	err = ieee80211_assign_link_chanctx(link, new_ctx, false);
1414 	if (err) {
1415 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1416 			ieee80211_free_chanctx(local, new_ctx, false);
1417 
1418 		goto out;
1419 	}
1420 
1421 out:
1422 	ieee80211_link_chanctx_reservation_complete(link);
1423 	return err;
1424 }
1425 
1426 static bool
ieee80211_link_has_in_place_reservation(struct ieee80211_link_data * link)1427 ieee80211_link_has_in_place_reservation(struct ieee80211_link_data *link)
1428 {
1429 	struct ieee80211_sub_if_data *sdata = link->sdata;
1430 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1431 
1432 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1433 
1434 	new_ctx = link->reserved_chanctx;
1435 	old_ctx = ieee80211_link_get_chanctx(link);
1436 
1437 	if (!old_ctx)
1438 		return false;
1439 
1440 	if (WARN_ON(!new_ctx))
1441 		return false;
1442 
1443 	if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1444 		return false;
1445 
1446 	if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1447 		return false;
1448 
1449 	return true;
1450 }
1451 
ieee80211_chsw_switch_vifs(struct ieee80211_local * local,int n_vifs)1452 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1453 				      int n_vifs)
1454 {
1455 	struct ieee80211_vif_chanctx_switch *vif_chsw;
1456 	struct ieee80211_link_data *link;
1457 	struct ieee80211_chanctx *ctx, *old_ctx;
1458 	int i, err;
1459 
1460 	lockdep_assert_wiphy(local->hw.wiphy);
1461 
1462 	vif_chsw = kcalloc(n_vifs, sizeof(vif_chsw[0]), GFP_KERNEL);
1463 	if (!vif_chsw)
1464 		return -ENOMEM;
1465 
1466 	i = 0;
1467 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1468 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1469 			continue;
1470 
1471 		if (WARN_ON(!ctx->replace_ctx)) {
1472 			err = -EINVAL;
1473 			goto out;
1474 		}
1475 
1476 		list_for_each_entry(link, &ctx->reserved_links,
1477 				    reserved_chanctx_list) {
1478 			if (!ieee80211_link_has_in_place_reservation(link))
1479 				continue;
1480 
1481 			old_ctx = ieee80211_link_get_chanctx(link);
1482 			vif_chsw[i].vif = &link->sdata->vif;
1483 			vif_chsw[i].old_ctx = &old_ctx->conf;
1484 			vif_chsw[i].new_ctx = &ctx->conf;
1485 			vif_chsw[i].link_conf = link->conf;
1486 
1487 			i++;
1488 		}
1489 	}
1490 
1491 	err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1492 				     CHANCTX_SWMODE_SWAP_CONTEXTS);
1493 
1494 out:
1495 	kfree(vif_chsw);
1496 	return err;
1497 }
1498 
ieee80211_chsw_switch_ctxs(struct ieee80211_local * local)1499 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1500 {
1501 	struct ieee80211_chanctx *ctx;
1502 	int err;
1503 
1504 	lockdep_assert_wiphy(local->hw.wiphy);
1505 
1506 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1507 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1508 			continue;
1509 
1510 		if (!list_empty(&ctx->replace_ctx->assigned_links))
1511 			continue;
1512 
1513 		ieee80211_del_chanctx(local, ctx->replace_ctx, false);
1514 		err = ieee80211_add_chanctx(local, ctx);
1515 		if (err)
1516 			goto err;
1517 	}
1518 
1519 	return 0;
1520 
1521 err:
1522 	WARN_ON(ieee80211_add_chanctx(local, ctx));
1523 	list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1524 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1525 			continue;
1526 
1527 		if (!list_empty(&ctx->replace_ctx->assigned_links))
1528 			continue;
1529 
1530 		ieee80211_del_chanctx(local, ctx, false);
1531 		WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1532 	}
1533 
1534 	return err;
1535 }
1536 
ieee80211_vif_use_reserved_switch(struct ieee80211_local * local)1537 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1538 {
1539 	struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1540 	int err, n_assigned, n_reserved, n_ready;
1541 	int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1542 
1543 	lockdep_assert_wiphy(local->hw.wiphy);
1544 
1545 	/*
1546 	 * If there are 2 independent pairs of channel contexts performing
1547 	 * cross-switch of their vifs this code will still wait until both are
1548 	 * ready even though it could be possible to switch one before the
1549 	 * other is ready.
1550 	 *
1551 	 * For practical reasons and code simplicity just do a single huge
1552 	 * switch.
1553 	 */
1554 
1555 	/*
1556 	 * Verify if the reservation is still feasible.
1557 	 *  - if it's not then disconnect
1558 	 *  - if it is but not all vifs necessary are ready then defer
1559 	 */
1560 
1561 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1562 		struct ieee80211_link_data *link;
1563 
1564 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1565 			continue;
1566 
1567 		if (WARN_ON(!ctx->replace_ctx)) {
1568 			err = -EINVAL;
1569 			goto err;
1570 		}
1571 
1572 		n_ctx++;
1573 
1574 		n_assigned = 0;
1575 		n_reserved = 0;
1576 		n_ready = 0;
1577 
1578 		list_for_each_entry(link, &ctx->replace_ctx->assigned_links,
1579 				    assigned_chanctx_list) {
1580 			n_assigned++;
1581 			if (link->reserved_chanctx) {
1582 				n_reserved++;
1583 				if (link->reserved_ready)
1584 					n_ready++;
1585 			}
1586 		}
1587 
1588 		if (n_assigned != n_reserved) {
1589 			if (n_ready == n_reserved) {
1590 				wiphy_info(local->hw.wiphy,
1591 					   "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1592 				err = -EBUSY;
1593 				goto err;
1594 			}
1595 
1596 			return -EAGAIN;
1597 		}
1598 
1599 		ctx->conf.radar_enabled = false;
1600 		list_for_each_entry(link, &ctx->reserved_links,
1601 				    reserved_chanctx_list) {
1602 			if (ieee80211_link_has_in_place_reservation(link) &&
1603 			    !link->reserved_ready)
1604 				return -EAGAIN;
1605 
1606 			old_ctx = ieee80211_link_get_chanctx(link);
1607 			if (old_ctx) {
1608 				if (old_ctx->replace_state ==
1609 				    IEEE80211_CHANCTX_WILL_BE_REPLACED)
1610 					n_vifs_switch++;
1611 				else
1612 					n_vifs_assign++;
1613 			} else {
1614 				n_vifs_ctxless++;
1615 			}
1616 
1617 			if (link->reserved_radar_required)
1618 				ctx->conf.radar_enabled = true;
1619 		}
1620 	}
1621 
1622 	if (WARN_ON(n_ctx == 0) ||
1623 	    WARN_ON(n_vifs_switch == 0 &&
1624 		    n_vifs_assign == 0 &&
1625 		    n_vifs_ctxless == 0)) {
1626 		err = -EINVAL;
1627 		goto err;
1628 	}
1629 
1630 	/* update station rate control and min width before switch */
1631 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1632 		struct ieee80211_link_data *link;
1633 
1634 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1635 			continue;
1636 
1637 		if (WARN_ON(!ctx->replace_ctx)) {
1638 			err = -EINVAL;
1639 			goto err;
1640 		}
1641 
1642 		list_for_each_entry(link, &ctx->reserved_links,
1643 				    reserved_chanctx_list) {
1644 			if (!ieee80211_link_has_in_place_reservation(link))
1645 				continue;
1646 
1647 			ieee80211_chan_bw_change(local,
1648 						 ieee80211_link_get_chanctx(link),
1649 						 true, true);
1650 		}
1651 
1652 		ieee80211_recalc_chanctx_min_def(local, ctx, NULL, true);
1653 	}
1654 
1655 	/*
1656 	 * All necessary vifs are ready. Perform the switch now depending on
1657 	 * reservations and driver capabilities.
1658 	 */
1659 
1660 	if (n_vifs_switch > 0) {
1661 		err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1662 		if (err)
1663 			goto err;
1664 	}
1665 
1666 	if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1667 		err = ieee80211_chsw_switch_ctxs(local);
1668 		if (err)
1669 			goto err;
1670 	}
1671 
1672 	/*
1673 	 * Update all structures, values and pointers to point to new channel
1674 	 * context(s).
1675 	 */
1676 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1677 		struct ieee80211_link_data *link, *link_tmp;
1678 
1679 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1680 			continue;
1681 
1682 		if (WARN_ON(!ctx->replace_ctx)) {
1683 			err = -EINVAL;
1684 			goto err;
1685 		}
1686 
1687 		list_for_each_entry(link, &ctx->reserved_links,
1688 				    reserved_chanctx_list) {
1689 			struct ieee80211_sub_if_data *sdata = link->sdata;
1690 			struct ieee80211_bss_conf *link_conf = link->conf;
1691 			u64 changed = 0;
1692 
1693 			if (!ieee80211_link_has_in_place_reservation(link))
1694 				continue;
1695 
1696 			rcu_assign_pointer(link_conf->chanctx_conf,
1697 					   &ctx->conf);
1698 
1699 			if (sdata->vif.type == NL80211_IFTYPE_AP)
1700 				__ieee80211_link_copy_chanctx_to_vlans(link,
1701 								       false);
1702 
1703 			ieee80211_check_fast_xmit_iface(sdata);
1704 
1705 			link->radar_required = link->reserved_radar_required;
1706 
1707 			if (link_conf->chanreq.oper.width != link->reserved.oper.width)
1708 				changed = BSS_CHANGED_BANDWIDTH;
1709 
1710 			ieee80211_link_update_chanreq(link, &link->reserved);
1711 			if (changed)
1712 				ieee80211_link_info_change_notify(sdata,
1713 								  link,
1714 								  changed);
1715 
1716 			ieee80211_recalc_txpower(sdata, false);
1717 		}
1718 
1719 		ieee80211_recalc_chanctx_chantype(local, ctx);
1720 		ieee80211_recalc_smps_chanctx(local, ctx);
1721 		ieee80211_recalc_radar_chanctx(local, ctx);
1722 		ieee80211_recalc_chanctx_min_def(local, ctx, NULL, false);
1723 
1724 		list_for_each_entry_safe(link, link_tmp, &ctx->reserved_links,
1725 					 reserved_chanctx_list) {
1726 			if (ieee80211_link_get_chanctx(link) != ctx)
1727 				continue;
1728 
1729 			list_del(&link->reserved_chanctx_list);
1730 			list_move(&link->assigned_chanctx_list,
1731 				  &ctx->assigned_links);
1732 			link->reserved_chanctx = NULL;
1733 
1734 			ieee80211_link_chanctx_reservation_complete(link);
1735 			ieee80211_chan_bw_change(local, ctx, false, false);
1736 		}
1737 
1738 		/*
1739 		 * This context might have been a dependency for an already
1740 		 * ready re-assign reservation interface that was deferred. Do
1741 		 * not propagate error to the caller though. The in-place
1742 		 * reservation for originally requested interface has already
1743 		 * succeeded at this point.
1744 		 */
1745 		list_for_each_entry_safe(link, link_tmp, &ctx->reserved_links,
1746 					 reserved_chanctx_list) {
1747 			if (WARN_ON(ieee80211_link_has_in_place_reservation(link)))
1748 				continue;
1749 
1750 			if (WARN_ON(link->reserved_chanctx != ctx))
1751 				continue;
1752 
1753 			if (!link->reserved_ready)
1754 				continue;
1755 
1756 			if (ieee80211_link_get_chanctx(link))
1757 				err = ieee80211_link_use_reserved_reassign(link);
1758 			else
1759 				err = ieee80211_link_use_reserved_assign(link);
1760 
1761 			if (err) {
1762 				link_info(link,
1763 					  "failed to finalize (re-)assign reservation (err=%d)\n",
1764 					  err);
1765 				ieee80211_link_unreserve_chanctx(link);
1766 				cfg80211_stop_iface(local->hw.wiphy,
1767 						    &link->sdata->wdev,
1768 						    GFP_KERNEL);
1769 			}
1770 		}
1771 	}
1772 
1773 	/*
1774 	 * Finally free old contexts
1775 	 */
1776 
1777 	list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1778 		if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1779 			continue;
1780 
1781 		ctx->replace_ctx->replace_ctx = NULL;
1782 		ctx->replace_ctx->replace_state =
1783 				IEEE80211_CHANCTX_REPLACE_NONE;
1784 
1785 		list_del_rcu(&ctx->list);
1786 		kfree_rcu(ctx, rcu_head);
1787 	}
1788 
1789 	return 0;
1790 
1791 err:
1792 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1793 		struct ieee80211_link_data *link, *link_tmp;
1794 
1795 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1796 			continue;
1797 
1798 		list_for_each_entry_safe(link, link_tmp, &ctx->reserved_links,
1799 					 reserved_chanctx_list) {
1800 			ieee80211_link_unreserve_chanctx(link);
1801 			ieee80211_link_chanctx_reservation_complete(link);
1802 		}
1803 	}
1804 
1805 	return err;
1806 }
1807 
__ieee80211_link_release_channel(struct ieee80211_link_data * link,bool skip_idle_recalc)1808 void __ieee80211_link_release_channel(struct ieee80211_link_data *link,
1809 				      bool skip_idle_recalc)
1810 {
1811 	struct ieee80211_sub_if_data *sdata = link->sdata;
1812 	struct ieee80211_bss_conf *link_conf = link->conf;
1813 	struct ieee80211_local *local = sdata->local;
1814 	struct ieee80211_chanctx_conf *conf;
1815 	struct ieee80211_chanctx *ctx;
1816 	bool use_reserved_switch = false;
1817 
1818 	lockdep_assert_wiphy(local->hw.wiphy);
1819 
1820 	conf = rcu_dereference_protected(link_conf->chanctx_conf,
1821 					 lockdep_is_held(&local->hw.wiphy->mtx));
1822 	if (!conf)
1823 		return;
1824 
1825 	ctx = container_of(conf, struct ieee80211_chanctx, conf);
1826 
1827 	if (link->reserved_chanctx) {
1828 		if (link->reserved_chanctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER &&
1829 		    ieee80211_chanctx_num_reserved(local, link->reserved_chanctx) > 1)
1830 			use_reserved_switch = true;
1831 
1832 		ieee80211_link_unreserve_chanctx(link);
1833 	}
1834 
1835 	ieee80211_assign_link_chanctx(link, NULL, false);
1836 	if (ieee80211_chanctx_refcount(local, ctx) == 0)
1837 		ieee80211_free_chanctx(local, ctx, skip_idle_recalc);
1838 
1839 	link->radar_required = false;
1840 
1841 	/* Unreserving may ready an in-place reservation. */
1842 	if (use_reserved_switch)
1843 		ieee80211_vif_use_reserved_switch(local);
1844 }
1845 
_ieee80211_link_use_channel(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode,bool assign_on_failure)1846 int _ieee80211_link_use_channel(struct ieee80211_link_data *link,
1847 				const struct ieee80211_chan_req *chanreq,
1848 				enum ieee80211_chanctx_mode mode,
1849 				bool assign_on_failure)
1850 {
1851 	struct ieee80211_sub_if_data *sdata = link->sdata;
1852 	struct ieee80211_local *local = sdata->local;
1853 	struct ieee80211_chanctx *ctx;
1854 	u8 radar_detect_width = 0;
1855 	bool reserved = false;
1856 	int radio_idx;
1857 	int ret;
1858 
1859 	lockdep_assert_wiphy(local->hw.wiphy);
1860 
1861 	if (!ieee80211_vif_link_active(&sdata->vif, link->link_id)) {
1862 		ieee80211_link_update_chanreq(link, chanreq);
1863 		return 0;
1864 	}
1865 
1866 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1867 					    &chanreq->oper,
1868 					    sdata->wdev.iftype);
1869 	if (ret < 0)
1870 		goto out;
1871 	if (ret > 0)
1872 		radar_detect_width = BIT(chanreq->oper.width);
1873 
1874 	link->radar_required = ret;
1875 
1876 	ret = ieee80211_check_combinations(sdata, &chanreq->oper, mode,
1877 					   radar_detect_width, -1);
1878 	if (ret < 0)
1879 		goto out;
1880 
1881 	__ieee80211_link_release_channel(link, false);
1882 
1883 	ctx = ieee80211_find_chanctx(local, link, chanreq, mode);
1884 	/* Note: context is now reserved */
1885 	if (ctx)
1886 		reserved = true;
1887 	else if (!ieee80211_find_available_radio(local, chanreq, &radio_idx))
1888 		ctx = ERR_PTR(-EBUSY);
1889 	else
1890 		ctx = ieee80211_new_chanctx(local, chanreq, mode,
1891 					    assign_on_failure, radio_idx);
1892 	if (IS_ERR(ctx)) {
1893 		ret = PTR_ERR(ctx);
1894 		goto out;
1895 	}
1896 
1897 	ieee80211_link_update_chanreq(link, chanreq);
1898 
1899 	ret = ieee80211_assign_link_chanctx(link, ctx, assign_on_failure);
1900 
1901 	if (reserved) {
1902 		/* remove reservation */
1903 		WARN_ON(link->reserved_chanctx != ctx);
1904 		link->reserved_chanctx = NULL;
1905 		list_del(&link->reserved_chanctx_list);
1906 	}
1907 
1908 	if (ret) {
1909 		/* if assign fails refcount stays the same */
1910 		if (ieee80211_chanctx_refcount(local, ctx) == 0)
1911 			ieee80211_free_chanctx(local, ctx, false);
1912 		goto out;
1913 	}
1914 
1915 	ieee80211_recalc_smps_chanctx(local, ctx);
1916 	ieee80211_recalc_radar_chanctx(local, ctx);
1917  out:
1918 	if (ret)
1919 		link->radar_required = false;
1920 
1921 	return ret;
1922 }
1923 
ieee80211_link_use_reserved_context(struct ieee80211_link_data * link)1924 int ieee80211_link_use_reserved_context(struct ieee80211_link_data *link)
1925 {
1926 	struct ieee80211_sub_if_data *sdata = link->sdata;
1927 	struct ieee80211_local *local = sdata->local;
1928 	struct ieee80211_chanctx *new_ctx;
1929 	struct ieee80211_chanctx *old_ctx;
1930 	int err;
1931 
1932 	lockdep_assert_wiphy(local->hw.wiphy);
1933 
1934 	new_ctx = link->reserved_chanctx;
1935 	old_ctx = ieee80211_link_get_chanctx(link);
1936 
1937 	if (WARN_ON(!new_ctx))
1938 		return -EINVAL;
1939 
1940 	if (WARN_ON(new_ctx->replace_state ==
1941 		    IEEE80211_CHANCTX_WILL_BE_REPLACED))
1942 		return -EINVAL;
1943 
1944 	if (WARN_ON(link->reserved_ready))
1945 		return -EINVAL;
1946 
1947 	link->reserved_ready = true;
1948 
1949 	if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1950 		if (old_ctx)
1951 			return ieee80211_link_use_reserved_reassign(link);
1952 
1953 		return ieee80211_link_use_reserved_assign(link);
1954 	}
1955 
1956 	/*
1957 	 * In-place reservation may need to be finalized now either if:
1958 	 *  a) sdata is taking part in the swapping itself and is the last one
1959 	 *  b) sdata has switched with a re-assign reservation to an existing
1960 	 *     context readying in-place switching of old_ctx
1961 	 *
1962 	 * In case of (b) do not propagate the error up because the requested
1963 	 * sdata already switched successfully. Just spill an extra warning.
1964 	 * The ieee80211_vif_use_reserved_switch() already stops all necessary
1965 	 * interfaces upon failure.
1966 	 */
1967 	if ((old_ctx &&
1968 	     old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1969 	    new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1970 		err = ieee80211_vif_use_reserved_switch(local);
1971 		if (err && err != -EAGAIN) {
1972 			if (new_ctx->replace_state ==
1973 			    IEEE80211_CHANCTX_REPLACES_OTHER)
1974 				return err;
1975 
1976 			wiphy_info(local->hw.wiphy,
1977 				   "depending in-place reservation failed (err=%d)\n",
1978 				   err);
1979 		}
1980 	}
1981 
1982 	return 0;
1983 }
1984 
1985 /*
1986  * This is similar to ieee80211_chanctx_compatible(), but rechecks
1987  * against all the links actually using it (except the one that's
1988  * passed, since that one is changing).
1989  * This is done in order to allow changes to the AP's bandwidth for
1990  * wider bandwidth OFDMA purposes, which wouldn't be treated as
1991  * compatible by ieee80211_chanctx_recheck() but is OK if the link
1992  * requesting the update is the only one using it.
1993  */
1994 static const struct ieee80211_chan_req *
ieee80211_chanctx_recheck(struct ieee80211_local * local,struct ieee80211_link_data * skip_link,struct ieee80211_chanctx * ctx,const struct ieee80211_chan_req * req,struct ieee80211_chan_req * tmp)1995 ieee80211_chanctx_recheck(struct ieee80211_local *local,
1996 			  struct ieee80211_link_data *skip_link,
1997 			  struct ieee80211_chanctx *ctx,
1998 			  const struct ieee80211_chan_req *req,
1999 			  struct ieee80211_chan_req *tmp)
2000 {
2001 	const struct ieee80211_chan_req *ret = req;
2002 	struct ieee80211_link_data *link;
2003 
2004 	lockdep_assert_wiphy(local->hw.wiphy);
2005 
2006 	for_each_sdata_link(local, link) {
2007 		if (link == skip_link)
2008 			continue;
2009 
2010 		if (rcu_access_pointer(link->conf->chanctx_conf) == &ctx->conf) {
2011 			ret = ieee80211_chanreq_compatible(ret,
2012 							   &link->conf->chanreq,
2013 							   tmp);
2014 			if (!ret)
2015 				return NULL;
2016 		}
2017 
2018 		if (link->reserved_chanctx == ctx) {
2019 			ret = ieee80211_chanreq_compatible(ret,
2020 							   &link->reserved,
2021 							   tmp);
2022 			if (!ret)
2023 				return NULL;
2024 		}
2025 	}
2026 
2027 	*tmp = *ret;
2028 	return tmp;
2029 }
2030 
ieee80211_link_change_chanreq(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq,u64 * changed)2031 int ieee80211_link_change_chanreq(struct ieee80211_link_data *link,
2032 				  const struct ieee80211_chan_req *chanreq,
2033 				  u64 *changed)
2034 {
2035 	struct ieee80211_sub_if_data *sdata = link->sdata;
2036 	struct ieee80211_bss_conf *link_conf = link->conf;
2037 	struct ieee80211_local *local = sdata->local;
2038 	struct ieee80211_chanctx_conf *conf;
2039 	struct ieee80211_chanctx *ctx;
2040 	const struct ieee80211_chan_req *compat;
2041 	struct ieee80211_chan_req tmp;
2042 
2043 	lockdep_assert_wiphy(local->hw.wiphy);
2044 
2045 	if (!cfg80211_chandef_usable(sdata->local->hw.wiphy,
2046 				     &chanreq->oper,
2047 				     IEEE80211_CHAN_DISABLED))
2048 		return -EINVAL;
2049 
2050 	/* for non-HT 20 MHz the rest doesn't matter */
2051 	if (chanreq->oper.width == NL80211_CHAN_WIDTH_20_NOHT &&
2052 	    cfg80211_chandef_identical(&chanreq->oper, &link_conf->chanreq.oper))
2053 		return 0;
2054 
2055 	/* but you cannot switch to/from it */
2056 	if (chanreq->oper.width == NL80211_CHAN_WIDTH_20_NOHT ||
2057 	    link_conf->chanreq.oper.width == NL80211_CHAN_WIDTH_20_NOHT)
2058 		return -EINVAL;
2059 
2060 	conf = rcu_dereference_protected(link_conf->chanctx_conf,
2061 					 lockdep_is_held(&local->hw.wiphy->mtx));
2062 	if (!conf)
2063 		return -EINVAL;
2064 
2065 	ctx = container_of(conf, struct ieee80211_chanctx, conf);
2066 
2067 	compat = ieee80211_chanctx_recheck(local, link, ctx, chanreq, &tmp);
2068 	if (!compat)
2069 		return -EINVAL;
2070 
2071 	switch (ctx->replace_state) {
2072 	case IEEE80211_CHANCTX_REPLACE_NONE:
2073 		if (!ieee80211_chanctx_reserved_chanreq(local, ctx, compat,
2074 							&tmp))
2075 			return -EBUSY;
2076 		break;
2077 	case IEEE80211_CHANCTX_WILL_BE_REPLACED:
2078 		/* TODO: Perhaps the bandwidth change could be treated as a
2079 		 * reservation itself? */
2080 		return -EBUSY;
2081 	case IEEE80211_CHANCTX_REPLACES_OTHER:
2082 		/* channel context that is going to replace another channel
2083 		 * context doesn't really exist and shouldn't be assigned
2084 		 * anywhere yet */
2085 		WARN_ON(1);
2086 		break;
2087 	}
2088 
2089 	ieee80211_link_update_chanreq(link, chanreq);
2090 
2091 	ieee80211_recalc_chanctx_chantype(local, ctx);
2092 
2093 	*changed |= BSS_CHANGED_BANDWIDTH;
2094 	return 0;
2095 }
2096 
ieee80211_link_release_channel(struct ieee80211_link_data * link)2097 void ieee80211_link_release_channel(struct ieee80211_link_data *link)
2098 {
2099 	struct ieee80211_sub_if_data *sdata = link->sdata;
2100 
2101 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2102 		return;
2103 
2104 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
2105 
2106 	if (rcu_access_pointer(link->conf->chanctx_conf))
2107 		__ieee80211_link_release_channel(link, false);
2108 }
2109 
ieee80211_link_vlan_copy_chanctx(struct ieee80211_link_data * link)2110 void ieee80211_link_vlan_copy_chanctx(struct ieee80211_link_data *link)
2111 {
2112 	struct ieee80211_sub_if_data *sdata = link->sdata;
2113 	unsigned int link_id = link->link_id;
2114 	struct ieee80211_bss_conf *link_conf = link->conf;
2115 	struct ieee80211_bss_conf *ap_conf;
2116 	struct ieee80211_local *local = sdata->local;
2117 	struct ieee80211_sub_if_data *ap;
2118 	struct ieee80211_chanctx_conf *conf;
2119 
2120 	lockdep_assert_wiphy(local->hw.wiphy);
2121 
2122 	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
2123 		return;
2124 
2125 	ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
2126 
2127 	ap_conf = wiphy_dereference(local->hw.wiphy,
2128 				    ap->vif.link_conf[link_id]);
2129 	conf = wiphy_dereference(local->hw.wiphy,
2130 				 ap_conf->chanctx_conf);
2131 	rcu_assign_pointer(link_conf->chanctx_conf, conf);
2132 }
2133 
ieee80211_iter_chan_contexts_atomic(struct ieee80211_hw * hw,void (* iter)(struct ieee80211_hw * hw,struct ieee80211_chanctx_conf * chanctx_conf,void * data),void * iter_data)2134 void ieee80211_iter_chan_contexts_atomic(
2135 	struct ieee80211_hw *hw,
2136 	void (*iter)(struct ieee80211_hw *hw,
2137 		     struct ieee80211_chanctx_conf *chanctx_conf,
2138 		     void *data),
2139 	void *iter_data)
2140 {
2141 	struct ieee80211_local *local = hw_to_local(hw);
2142 	struct ieee80211_chanctx *ctx;
2143 
2144 	rcu_read_lock();
2145 	list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
2146 		if (ctx->driver_present)
2147 			iter(hw, &ctx->conf, iter_data);
2148 	rcu_read_unlock();
2149 }
2150 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);
2151