xref: /linux/net/mac80211/chan.c (revision 3fd6c59042dbba50391e30862beac979491145fe)
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_STATION:
327 			if (!link->sdata->vif.cfg.assoc) {
328 				/*
329 				 * The AP's sta->bandwidth may not yet be set
330 				 * at this point (pre-association), so simply
331 				 * take the width from the chandef. We cannot
332 				 * have TDLS peers yet (only after association).
333 				 */
334 				width = link->conf->chanreq.oper.width;
335 				break;
336 			}
337 			/*
338 			 * otherwise just use min_def like in AP, depending on what
339 			 * we currently think the AP STA (and possibly TDLS peers)
340 			 * require(s)
341 			 */
342 			fallthrough;
343 		case NL80211_IFTYPE_AP:
344 		case NL80211_IFTYPE_AP_VLAN:
345 			width = ieee80211_get_max_required_bw(link);
346 			break;
347 		case NL80211_IFTYPE_P2P_DEVICE:
348 		case NL80211_IFTYPE_NAN:
349 			continue;
350 		case NL80211_IFTYPE_MONITOR:
351 			WARN_ON_ONCE(!ieee80211_hw_check(&local->hw,
352 							 NO_VIRTUAL_MONITOR));
353 			fallthrough;
354 		case NL80211_IFTYPE_ADHOC:
355 		case NL80211_IFTYPE_MESH_POINT:
356 		case NL80211_IFTYPE_OCB:
357 			width = link->conf->chanreq.oper.width;
358 			break;
359 		case NL80211_IFTYPE_WDS:
360 		case NL80211_IFTYPE_UNSPECIFIED:
361 		case NUM_NL80211_IFTYPES:
362 		case NL80211_IFTYPE_P2P_CLIENT:
363 		case NL80211_IFTYPE_P2P_GO:
364 			WARN_ON_ONCE(1);
365 		}
366 
367 		max_bw = max(max_bw, width);
368 	}
369 
370 	/* use the configured bandwidth in case of monitor interface */
371 	sdata = wiphy_dereference(local->hw.wiphy, local->monitor_sdata);
372 	if (sdata &&
373 	    rcu_access_pointer(sdata->vif.bss_conf.chanctx_conf) == &ctx->conf)
374 		max_bw = max(max_bw, ctx->conf.def.width);
375 
376 	return max_bw;
377 }
378 
379 /*
380  * recalc the min required chan width of the channel context, which is
381  * the max of min required widths of all the interfaces bound to this
382  * channel context.
383  */
384 static u32
_ieee80211_recalc_chanctx_min_def(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_link_data * rsvd_for,bool check_reserved)385 _ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
386 				  struct ieee80211_chanctx *ctx,
387 				  struct ieee80211_link_data *rsvd_for,
388 				  bool check_reserved)
389 {
390 	enum nl80211_chan_width max_bw;
391 	struct cfg80211_chan_def min_def;
392 
393 	lockdep_assert_wiphy(local->hw.wiphy);
394 
395 	/* don't optimize non-20MHz based and radar_enabled confs */
396 	if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
397 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
398 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_1 ||
399 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_2 ||
400 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_4 ||
401 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_8 ||
402 	    ctx->conf.def.width == NL80211_CHAN_WIDTH_16 ||
403 	    ctx->conf.radar_enabled) {
404 		ctx->conf.min_def = ctx->conf.def;
405 		return 0;
406 	}
407 
408 	max_bw = ieee80211_get_chanctx_max_required_bw(local, ctx, rsvd_for,
409 						       check_reserved);
410 
411 	/* downgrade chandef up to max_bw */
412 	min_def = ctx->conf.def;
413 	while (min_def.width > max_bw)
414 		ieee80211_chandef_downgrade(&min_def, NULL);
415 
416 	if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
417 		return 0;
418 
419 	ctx->conf.min_def = min_def;
420 	if (!ctx->driver_present)
421 		return 0;
422 
423 	return IEEE80211_CHANCTX_CHANGE_MIN_DEF;
424 }
425 
ieee80211_chan_bw_change(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,bool reserved,bool narrowed)426 static void ieee80211_chan_bw_change(struct ieee80211_local *local,
427 				     struct ieee80211_chanctx *ctx,
428 				     bool reserved, bool narrowed)
429 {
430 	struct sta_info *sta;
431 	struct ieee80211_supported_band *sband =
432 		local->hw.wiphy->bands[ctx->conf.def.chan->band];
433 
434 	rcu_read_lock();
435 	list_for_each_entry_rcu(sta, &local->sta_list,
436 				list) {
437 		struct ieee80211_sub_if_data *sdata = sta->sdata;
438 		enum ieee80211_sta_rx_bandwidth new_sta_bw;
439 		unsigned int link_id;
440 
441 		if (!ieee80211_sdata_running(sta->sdata))
442 			continue;
443 
444 		for (link_id = 0; link_id < ARRAY_SIZE(sta->sdata->link); link_id++) {
445 			struct ieee80211_link_data *link =
446 				rcu_dereference(sdata->link[link_id]);
447 			struct ieee80211_bss_conf *link_conf;
448 			struct cfg80211_chan_def *new_chandef;
449 			struct link_sta_info *link_sta;
450 
451 			if (!link)
452 				continue;
453 
454 			link_conf = link->conf;
455 
456 			if (rcu_access_pointer(link_conf->chanctx_conf) != &ctx->conf)
457 				continue;
458 
459 			link_sta = rcu_dereference(sta->link[link_id]);
460 			if (!link_sta)
461 				continue;
462 
463 			if (reserved)
464 				new_chandef = &link->reserved.oper;
465 			else
466 				new_chandef = &link_conf->chanreq.oper;
467 
468 			new_sta_bw = _ieee80211_sta_cur_vht_bw(link_sta,
469 							       new_chandef);
470 
471 			/* nothing change */
472 			if (new_sta_bw == link_sta->pub->bandwidth)
473 				continue;
474 
475 			/* vif changed to narrow BW and narrow BW for station wasn't
476 			 * requested or vice versa */
477 			if ((new_sta_bw < link_sta->pub->bandwidth) == !narrowed)
478 				continue;
479 
480 			link_sta->pub->bandwidth = new_sta_bw;
481 			rate_control_rate_update(local, sband, link_sta,
482 						 IEEE80211_RC_BW_CHANGED);
483 		}
484 	}
485 	rcu_read_unlock();
486 }
487 
488 /*
489  * recalc the min required chan width of the channel context, which is
490  * the max of min required widths of all the interfaces bound to this
491  * channel context.
492  */
ieee80211_recalc_chanctx_min_def(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_link_data * rsvd_for,bool check_reserved)493 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
494 				      struct ieee80211_chanctx *ctx,
495 				      struct ieee80211_link_data *rsvd_for,
496 				      bool check_reserved)
497 {
498 	u32 changed = _ieee80211_recalc_chanctx_min_def(local, ctx, rsvd_for,
499 							check_reserved);
500 
501 	if (!changed)
502 		return;
503 
504 	/* check is BW narrowed */
505 	ieee80211_chan_bw_change(local, ctx, false, true);
506 
507 	drv_change_chanctx(local, ctx, changed);
508 
509 	/* check is BW wider */
510 	ieee80211_chan_bw_change(local, ctx, false, false);
511 }
512 
_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)513 static void _ieee80211_change_chanctx(struct ieee80211_local *local,
514 				      struct ieee80211_chanctx *ctx,
515 				      struct ieee80211_chanctx *old_ctx,
516 				      const struct ieee80211_chan_req *chanreq,
517 				      struct ieee80211_link_data *rsvd_for)
518 {
519 	const struct cfg80211_chan_def *chandef = &chanreq->oper;
520 	struct ieee80211_chan_req ctx_req = {
521 		.oper = ctx->conf.def,
522 		.ap = ctx->conf.ap,
523 	};
524 	u32 changed = 0;
525 
526 	/* expected to handle only 20/40/80/160/320 channel widths */
527 	switch (chandef->width) {
528 	case NL80211_CHAN_WIDTH_20_NOHT:
529 	case NL80211_CHAN_WIDTH_20:
530 	case NL80211_CHAN_WIDTH_40:
531 	case NL80211_CHAN_WIDTH_80:
532 	case NL80211_CHAN_WIDTH_80P80:
533 	case NL80211_CHAN_WIDTH_160:
534 	case NL80211_CHAN_WIDTH_320:
535 		break;
536 	default:
537 		WARN_ON(1);
538 	}
539 
540 	/* Check maybe BW narrowed - we do this _before_ calling recalc_chanctx_min_def
541 	 * due to maybe not returning from it, e.g in case new context was added
542 	 * first time with all parameters up to date.
543 	 */
544 	ieee80211_chan_bw_change(local, old_ctx, false, true);
545 
546 	if (ieee80211_chanreq_identical(&ctx_req, chanreq)) {
547 		ieee80211_recalc_chanctx_min_def(local, ctx, rsvd_for, false);
548 		return;
549 	}
550 
551 	WARN_ON(ieee80211_chanctx_refcount(local, ctx) > 1 &&
552 		!cfg80211_chandef_compatible(&ctx->conf.def, &chanreq->oper));
553 
554 	ieee80211_remove_wbrf(local, &ctx->conf.def);
555 
556 	if (!cfg80211_chandef_identical(&ctx->conf.def, &chanreq->oper)) {
557 		if (ctx->conf.def.width != chanreq->oper.width)
558 			changed |= IEEE80211_CHANCTX_CHANGE_WIDTH;
559 		if (ctx->conf.def.punctured != chanreq->oper.punctured)
560 			changed |= IEEE80211_CHANCTX_CHANGE_PUNCTURING;
561 	}
562 	if (!cfg80211_chandef_identical(&ctx->conf.ap, &chanreq->ap))
563 		changed |= IEEE80211_CHANCTX_CHANGE_AP;
564 	ctx->conf.def = *chandef;
565 	ctx->conf.ap = chanreq->ap;
566 
567 	/* check if min chanctx also changed */
568 	changed |= _ieee80211_recalc_chanctx_min_def(local, ctx, rsvd_for, false);
569 
570 	ieee80211_add_wbrf(local, &ctx->conf.def);
571 
572 	drv_change_chanctx(local, ctx, changed);
573 
574 	/* check if BW is wider */
575 	ieee80211_chan_bw_change(local, old_ctx, false, false);
576 }
577 
ieee80211_change_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,struct ieee80211_chanctx * old_ctx,const struct ieee80211_chan_req * chanreq)578 static void ieee80211_change_chanctx(struct ieee80211_local *local,
579 				     struct ieee80211_chanctx *ctx,
580 				     struct ieee80211_chanctx *old_ctx,
581 				     const struct ieee80211_chan_req *chanreq)
582 {
583 	_ieee80211_change_chanctx(local, ctx, old_ctx, chanreq, NULL);
584 }
585 
586 /* Note: if successful, the returned chanctx is reserved for the link */
587 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)588 ieee80211_find_chanctx(struct ieee80211_local *local,
589 		       struct ieee80211_link_data *link,
590 		       const struct ieee80211_chan_req *chanreq,
591 		       enum ieee80211_chanctx_mode mode)
592 {
593 	struct ieee80211_chan_req tmp;
594 	struct ieee80211_chanctx *ctx;
595 
596 	lockdep_assert_wiphy(local->hw.wiphy);
597 
598 	if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
599 		return NULL;
600 
601 	if (WARN_ON(link->reserved_chanctx))
602 		return NULL;
603 
604 	list_for_each_entry(ctx, &local->chanctx_list, list) {
605 		const struct ieee80211_chan_req *compat;
606 
607 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
608 			continue;
609 
610 		if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
611 			continue;
612 
613 		compat = ieee80211_chanctx_compatible(ctx, chanreq, &tmp);
614 		if (!compat)
615 			continue;
616 
617 		compat = ieee80211_chanctx_reserved_chanreq(local, ctx,
618 							    compat, &tmp);
619 		if (!compat)
620 			continue;
621 
622 		/*
623 		 * Reserve the chanctx temporarily, as the driver might change
624 		 * active links during callbacks we make into it below and/or
625 		 * later during assignment, which could (otherwise) cause the
626 		 * context to actually be removed.
627 		 */
628 		link->reserved_chanctx = ctx;
629 		list_add(&link->reserved_chanctx_list,
630 			 &ctx->reserved_links);
631 
632 		ieee80211_change_chanctx(local, ctx, ctx, compat);
633 
634 		return ctx;
635 	}
636 
637 	return NULL;
638 }
639 
ieee80211_is_radar_required(struct ieee80211_local * local)640 bool ieee80211_is_radar_required(struct ieee80211_local *local)
641 {
642 	struct ieee80211_link_data *link;
643 
644 	lockdep_assert_wiphy(local->hw.wiphy);
645 
646 	for_each_sdata_link(local, link) {
647 		if (link->radar_required)
648 			return true;
649 	}
650 
651 	return false;
652 }
653 
654 static bool
ieee80211_chanctx_radar_required(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)655 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
656 				 struct ieee80211_chanctx *ctx)
657 {
658 	struct ieee80211_chanctx_conf *conf = &ctx->conf;
659 	struct ieee80211_link_data *link;
660 
661 	lockdep_assert_wiphy(local->hw.wiphy);
662 
663 	for_each_sdata_link(local, link) {
664 		if (rcu_access_pointer(link->conf->chanctx_conf) != conf)
665 			continue;
666 		if (!link->radar_required)
667 			continue;
668 		return true;
669 	}
670 
671 	return false;
672 }
673 
674 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)675 ieee80211_alloc_chanctx(struct ieee80211_local *local,
676 			const struct ieee80211_chan_req *chanreq,
677 			enum ieee80211_chanctx_mode mode,
678 			int radio_idx)
679 {
680 	struct ieee80211_chanctx *ctx;
681 
682 	lockdep_assert_wiphy(local->hw.wiphy);
683 
684 	ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
685 	if (!ctx)
686 		return NULL;
687 
688 	INIT_LIST_HEAD(&ctx->assigned_links);
689 	INIT_LIST_HEAD(&ctx->reserved_links);
690 	ctx->conf.def = chanreq->oper;
691 	ctx->conf.ap = chanreq->ap;
692 	ctx->conf.rx_chains_static = 1;
693 	ctx->conf.rx_chains_dynamic = 1;
694 	ctx->mode = mode;
695 	ctx->conf.radar_enabled = false;
696 	ctx->conf.radio_idx = radio_idx;
697 	ctx->radar_detected = false;
698 	_ieee80211_recalc_chanctx_min_def(local, ctx, NULL, false);
699 
700 	return ctx;
701 }
702 
ieee80211_add_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)703 static int ieee80211_add_chanctx(struct ieee80211_local *local,
704 				 struct ieee80211_chanctx *ctx)
705 {
706 	u32 changed;
707 	int err;
708 
709 	lockdep_assert_wiphy(local->hw.wiphy);
710 
711 	ieee80211_add_wbrf(local, &ctx->conf.def);
712 
713 	/* turn idle off *before* setting channel -- some drivers need that */
714 	changed = ieee80211_idle_off(local);
715 	if (changed)
716 		ieee80211_hw_config(local, changed);
717 
718 	err = drv_add_chanctx(local, ctx);
719 	if (err) {
720 		ieee80211_recalc_idle(local);
721 		return err;
722 	}
723 
724 	return 0;
725 }
726 
727 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)728 ieee80211_new_chanctx(struct ieee80211_local *local,
729 		      const struct ieee80211_chan_req *chanreq,
730 		      enum ieee80211_chanctx_mode mode,
731 		      bool assign_on_failure,
732 		      int radio_idx)
733 {
734 	struct ieee80211_chanctx *ctx;
735 	int err;
736 
737 	lockdep_assert_wiphy(local->hw.wiphy);
738 
739 	ctx = ieee80211_alloc_chanctx(local, chanreq, mode, radio_idx);
740 	if (!ctx)
741 		return ERR_PTR(-ENOMEM);
742 
743 	err = ieee80211_add_chanctx(local, ctx);
744 	if (!assign_on_failure && err) {
745 		kfree(ctx);
746 		return ERR_PTR(err);
747 	}
748 	/* We ignored a driver error, see _ieee80211_set_active_links */
749 	WARN_ON_ONCE(err && !local->in_reconfig);
750 
751 	list_add_rcu(&ctx->list, &local->chanctx_list);
752 	return ctx;
753 }
754 
ieee80211_del_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,bool skip_idle_recalc)755 static void ieee80211_del_chanctx(struct ieee80211_local *local,
756 				  struct ieee80211_chanctx *ctx,
757 				  bool skip_idle_recalc)
758 {
759 	lockdep_assert_wiphy(local->hw.wiphy);
760 
761 	drv_remove_chanctx(local, ctx);
762 
763 	if (!skip_idle_recalc)
764 		ieee80211_recalc_idle(local);
765 
766 	ieee80211_remove_wbrf(local, &ctx->conf.def);
767 }
768 
ieee80211_free_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * ctx,bool skip_idle_recalc)769 static void ieee80211_free_chanctx(struct ieee80211_local *local,
770 				   struct ieee80211_chanctx *ctx,
771 				   bool skip_idle_recalc)
772 {
773 	lockdep_assert_wiphy(local->hw.wiphy);
774 
775 	WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
776 
777 	list_del_rcu(&ctx->list);
778 	ieee80211_del_chanctx(local, ctx, skip_idle_recalc);
779 	kfree_rcu(ctx, rcu_head);
780 }
781 
ieee80211_recalc_chanctx_chantype(struct ieee80211_local * local,struct ieee80211_chanctx * ctx)782 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
783 				       struct ieee80211_chanctx *ctx)
784 {
785 	struct ieee80211_chanctx_conf *conf = &ctx->conf;
786 	const struct ieee80211_chan_req *compat = NULL;
787 	struct ieee80211_link_data *link;
788 	struct ieee80211_chan_req tmp;
789 	struct sta_info *sta;
790 
791 	lockdep_assert_wiphy(local->hw.wiphy);
792 
793 	for_each_sdata_link(local, link) {
794 		struct ieee80211_bss_conf *link_conf;
795 
796 		if (link->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
797 			continue;
798 
799 		link_conf = link->conf;
800 
801 		if (rcu_access_pointer(link_conf->chanctx_conf) != conf)
802 			continue;
803 
804 		if (!compat)
805 			compat = &link_conf->chanreq;
806 
807 		compat = ieee80211_chanreq_compatible(&link_conf->chanreq,
808 						      compat, &tmp);
809 		if (WARN_ON_ONCE(!compat))
810 			return;
811 	}
812 
813 	if (WARN_ON_ONCE(!compat))
814 		return;
815 
816 	/* TDLS peers can sometimes affect the chandef width */
817 	list_for_each_entry(sta, &local->sta_list, list) {
818 		struct ieee80211_sub_if_data *sdata = sta->sdata;
819 		struct ieee80211_chan_req tdls_chanreq = {};
820 		int tdls_link_id;
821 
822 		if (!sta->uploaded ||
823 		    !test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW) ||
824 		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
825 		    !sta->tdls_chandef.chan)
826 			continue;
827 
828 		tdls_link_id = ieee80211_tdls_sta_link_id(sta);
829 		link = sdata_dereference(sdata->link[tdls_link_id], sdata);
830 		if (!link)
831 			continue;
832 
833 		if (rcu_access_pointer(link->conf->chanctx_conf) != conf)
834 			continue;
835 
836 		tdls_chanreq.oper = sta->tdls_chandef;
837 
838 		/* note this always fills and returns &tmp if compat */
839 		compat = ieee80211_chanreq_compatible(&tdls_chanreq,
840 						      compat, &tmp);
841 		if (WARN_ON_ONCE(!compat))
842 			return;
843 	}
844 
845 	ieee80211_change_chanctx(local, ctx, ctx, compat);
846 }
847 
ieee80211_recalc_radar_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * chanctx)848 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
849 					   struct ieee80211_chanctx *chanctx)
850 {
851 	bool radar_enabled;
852 
853 	lockdep_assert_wiphy(local->hw.wiphy);
854 
855 	radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
856 
857 	if (radar_enabled == chanctx->conf.radar_enabled)
858 		return;
859 
860 	chanctx->conf.radar_enabled = radar_enabled;
861 
862 	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
863 }
864 
ieee80211_assign_link_chanctx(struct ieee80211_link_data * link,struct ieee80211_chanctx * new_ctx,bool assign_on_failure)865 static int ieee80211_assign_link_chanctx(struct ieee80211_link_data *link,
866 					 struct ieee80211_chanctx *new_ctx,
867 					 bool assign_on_failure)
868 {
869 	struct ieee80211_sub_if_data *sdata = link->sdata;
870 	struct ieee80211_local *local = sdata->local;
871 	struct ieee80211_chanctx_conf *conf;
872 	struct ieee80211_chanctx *curr_ctx = NULL;
873 	bool new_idle;
874 	int ret;
875 
876 	if (WARN_ON(sdata->vif.type == NL80211_IFTYPE_NAN))
877 		return -EOPNOTSUPP;
878 
879 	conf = rcu_dereference_protected(link->conf->chanctx_conf,
880 					 lockdep_is_held(&local->hw.wiphy->mtx));
881 
882 	if (conf) {
883 		curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
884 
885 		drv_unassign_vif_chanctx(local, sdata, link->conf, curr_ctx);
886 		conf = NULL;
887 		list_del(&link->assigned_chanctx_list);
888 	}
889 
890 	if (new_ctx) {
891 		/* recalc considering the link we'll use it for now */
892 		ieee80211_recalc_chanctx_min_def(local, new_ctx, link, false);
893 
894 		ret = drv_assign_vif_chanctx(local, sdata, link->conf, new_ctx);
895 		if (assign_on_failure || !ret) {
896 			/* Need to continue, see _ieee80211_set_active_links */
897 			WARN_ON_ONCE(ret && !local->in_reconfig);
898 			ret = 0;
899 
900 			/* succeeded, so commit it to the data structures */
901 			conf = &new_ctx->conf;
902 			list_add(&link->assigned_chanctx_list,
903 				 &new_ctx->assigned_links);
904 		}
905 	} else {
906 		ret = 0;
907 	}
908 
909 	rcu_assign_pointer(link->conf->chanctx_conf, conf);
910 
911 	if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
912 		ieee80211_recalc_chanctx_chantype(local, curr_ctx);
913 		ieee80211_recalc_smps_chanctx(local, curr_ctx);
914 		ieee80211_recalc_radar_chanctx(local, curr_ctx);
915 		ieee80211_recalc_chanctx_min_def(local, curr_ctx, NULL, false);
916 	}
917 
918 	if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
919 		ieee80211_recalc_txpower(link, false);
920 		ieee80211_recalc_chanctx_min_def(local, new_ctx, NULL, false);
921 	}
922 
923 	if (conf) {
924 		new_idle = false;
925 	} else {
926 		struct ieee80211_link_data *tmp;
927 
928 		new_idle = true;
929 		for_each_sdata_link(local, tmp) {
930 			if (rcu_access_pointer(tmp->conf->chanctx_conf)) {
931 				new_idle = false;
932 				break;
933 			}
934 		}
935 	}
936 
937 	if (new_idle != sdata->vif.cfg.idle) {
938 		sdata->vif.cfg.idle = new_idle;
939 
940 		if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
941 		    sdata->vif.type != NL80211_IFTYPE_MONITOR)
942 			ieee80211_vif_cfg_change_notify(sdata, BSS_CHANGED_IDLE);
943 	}
944 
945 	ieee80211_check_fast_xmit_iface(sdata);
946 
947 	return ret;
948 }
949 
ieee80211_recalc_smps_chanctx(struct ieee80211_local * local,struct ieee80211_chanctx * chanctx)950 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
951 				   struct ieee80211_chanctx *chanctx)
952 {
953 	struct ieee80211_sub_if_data *sdata;
954 	u8 rx_chains_static, rx_chains_dynamic;
955 	struct ieee80211_link_data *link;
956 
957 	lockdep_assert_wiphy(local->hw.wiphy);
958 
959 	rx_chains_static = 1;
960 	rx_chains_dynamic = 1;
961 
962 	for_each_sdata_link(local, link) {
963 		u8 needed_static, needed_dynamic;
964 
965 		switch (link->sdata->vif.type) {
966 		case NL80211_IFTYPE_STATION:
967 			if (!link->sdata->u.mgd.associated)
968 				continue;
969 			break;
970 		case NL80211_IFTYPE_MONITOR:
971 			if (!ieee80211_hw_check(&local->hw, NO_VIRTUAL_MONITOR))
972 				continue;
973 			break;
974 		case NL80211_IFTYPE_AP:
975 		case NL80211_IFTYPE_ADHOC:
976 		case NL80211_IFTYPE_MESH_POINT:
977 		case NL80211_IFTYPE_OCB:
978 			break;
979 		default:
980 			continue;
981 		}
982 
983 		if (rcu_access_pointer(link->conf->chanctx_conf) != &chanctx->conf)
984 			continue;
985 
986 		if (link->sdata->vif.type == NL80211_IFTYPE_MONITOR) {
987 			rx_chains_dynamic = rx_chains_static = local->rx_chains;
988 			break;
989 		}
990 
991 		switch (link->smps_mode) {
992 		default:
993 			WARN_ONCE(1, "Invalid SMPS mode %d\n",
994 				  link->smps_mode);
995 			fallthrough;
996 		case IEEE80211_SMPS_OFF:
997 			needed_static = link->needed_rx_chains;
998 			needed_dynamic = link->needed_rx_chains;
999 			break;
1000 		case IEEE80211_SMPS_DYNAMIC:
1001 			needed_static = 1;
1002 			needed_dynamic = link->needed_rx_chains;
1003 			break;
1004 		case IEEE80211_SMPS_STATIC:
1005 			needed_static = 1;
1006 			needed_dynamic = 1;
1007 			break;
1008 		}
1009 
1010 		rx_chains_static = max(rx_chains_static, needed_static);
1011 		rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
1012 	}
1013 
1014 	/* Disable SMPS for the monitor interface */
1015 	sdata = wiphy_dereference(local->hw.wiphy, local->monitor_sdata);
1016 	if (sdata &&
1017 	    rcu_access_pointer(sdata->vif.bss_conf.chanctx_conf) == &chanctx->conf)
1018 		rx_chains_dynamic = rx_chains_static = local->rx_chains;
1019 
1020 	if (rx_chains_static == chanctx->conf.rx_chains_static &&
1021 	    rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
1022 		return;
1023 
1024 	chanctx->conf.rx_chains_static = rx_chains_static;
1025 	chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
1026 	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
1027 }
1028 
1029 static void
__ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data * link,bool clear)1030 __ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data *link,
1031 				       bool clear)
1032 {
1033 	struct ieee80211_sub_if_data *sdata = link->sdata;
1034 	unsigned int link_id = link->link_id;
1035 	struct ieee80211_bss_conf *link_conf = link->conf;
1036 	struct ieee80211_local *local __maybe_unused = sdata->local;
1037 	struct ieee80211_sub_if_data *vlan;
1038 	struct ieee80211_chanctx_conf *conf;
1039 
1040 	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
1041 		return;
1042 
1043 	lockdep_assert_wiphy(local->hw.wiphy);
1044 
1045 	/* Check that conf exists, even when clearing this function
1046 	 * must be called with the AP's channel context still there
1047 	 * as it would otherwise cause VLANs to have an invalid
1048 	 * channel context pointer for a while, possibly pointing
1049 	 * to a channel context that has already been freed.
1050 	 */
1051 	conf = rcu_dereference_protected(link_conf->chanctx_conf,
1052 					 lockdep_is_held(&local->hw.wiphy->mtx));
1053 	WARN_ON(!conf);
1054 
1055 	if (clear)
1056 		conf = NULL;
1057 
1058 	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
1059 		struct ieee80211_bss_conf *vlan_conf;
1060 
1061 		vlan_conf = wiphy_dereference(local->hw.wiphy,
1062 					      vlan->vif.link_conf[link_id]);
1063 		if (WARN_ON(!vlan_conf))
1064 			continue;
1065 
1066 		rcu_assign_pointer(vlan_conf->chanctx_conf, conf);
1067 	}
1068 }
1069 
ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data * link,bool clear)1070 void ieee80211_link_copy_chanctx_to_vlans(struct ieee80211_link_data *link,
1071 					  bool clear)
1072 {
1073 	struct ieee80211_local *local = link->sdata->local;
1074 
1075 	lockdep_assert_wiphy(local->hw.wiphy);
1076 
1077 	__ieee80211_link_copy_chanctx_to_vlans(link, clear);
1078 }
1079 
ieee80211_link_unreserve_chanctx(struct ieee80211_link_data * link)1080 int ieee80211_link_unreserve_chanctx(struct ieee80211_link_data *link)
1081 {
1082 	struct ieee80211_sub_if_data *sdata = link->sdata;
1083 	struct ieee80211_chanctx *ctx = link->reserved_chanctx;
1084 
1085 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1086 
1087 	if (WARN_ON(!ctx))
1088 		return -EINVAL;
1089 
1090 	list_del(&link->reserved_chanctx_list);
1091 	link->reserved_chanctx = NULL;
1092 
1093 	if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
1094 		if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1095 			if (WARN_ON(!ctx->replace_ctx))
1096 				return -EINVAL;
1097 
1098 			WARN_ON(ctx->replace_ctx->replace_state !=
1099 			        IEEE80211_CHANCTX_WILL_BE_REPLACED);
1100 			WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
1101 
1102 			ctx->replace_ctx->replace_ctx = NULL;
1103 			ctx->replace_ctx->replace_state =
1104 					IEEE80211_CHANCTX_REPLACE_NONE;
1105 
1106 			list_del_rcu(&ctx->list);
1107 			kfree_rcu(ctx, rcu_head);
1108 		} else {
1109 			ieee80211_free_chanctx(sdata->local, ctx, false);
1110 		}
1111 	}
1112 
1113 	return 0;
1114 }
1115 
1116 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)1117 ieee80211_replace_chanctx(struct ieee80211_local *local,
1118 			  const struct ieee80211_chan_req *chanreq,
1119 			  enum ieee80211_chanctx_mode mode,
1120 			  struct ieee80211_chanctx *curr_ctx)
1121 {
1122 	struct ieee80211_chanctx *new_ctx, *ctx;
1123 	struct wiphy *wiphy = local->hw.wiphy;
1124 	const struct wiphy_radio *radio;
1125 
1126 	if (!curr_ctx || (curr_ctx->replace_state ==
1127 			  IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1128 	    !list_empty(&curr_ctx->reserved_links)) {
1129 		/*
1130 		 * Another link already requested this context for a
1131 		 * reservation. Find another one hoping all links assigned
1132 		 * to it will also switch soon enough.
1133 		 *
1134 		 * TODO: This needs a little more work as some cases
1135 		 * (more than 2 chanctx capable devices) may fail which could
1136 		 * otherwise succeed provided some channel context juggling was
1137 		 * performed.
1138 		 *
1139 		 * Consider ctx1..3, link1..6, each ctx has 2 links. link1 and
1140 		 * link2 from ctx1 request new different chandefs starting 2
1141 		 * in-place reservations with ctx4 and ctx5 replacing ctx1 and
1142 		 * ctx2 respectively. Next link5 and link6 from ctx3 reserve
1143 		 * ctx4. If link3 and link4 remain on ctx2 as they are then this
1144 		 * fails unless `replace_ctx` from ctx5 is replaced with ctx3.
1145 		 */
1146 		list_for_each_entry(ctx, &local->chanctx_list, list) {
1147 			if (ctx->replace_state !=
1148 			    IEEE80211_CHANCTX_REPLACE_NONE)
1149 				continue;
1150 
1151 			if (!list_empty(&ctx->reserved_links))
1152 				continue;
1153 
1154 			if (ctx->conf.radio_idx >= 0) {
1155 				radio = &wiphy->radio[ctx->conf.radio_idx];
1156 				if (!cfg80211_radio_chandef_valid(radio, &chanreq->oper))
1157 					continue;
1158 			}
1159 
1160 			curr_ctx = ctx;
1161 			break;
1162 		}
1163 	}
1164 
1165 	/*
1166 	 * If that's true then all available contexts already have reservations
1167 	 * and cannot be used.
1168 	 */
1169 	if (!curr_ctx || (curr_ctx->replace_state ==
1170 			  IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1171 	    !list_empty(&curr_ctx->reserved_links))
1172 		return ERR_PTR(-EBUSY);
1173 
1174 	new_ctx = ieee80211_alloc_chanctx(local, chanreq, mode, -1);
1175 	if (!new_ctx)
1176 		return ERR_PTR(-ENOMEM);
1177 
1178 	new_ctx->replace_ctx = curr_ctx;
1179 	new_ctx->replace_state = IEEE80211_CHANCTX_REPLACES_OTHER;
1180 
1181 	curr_ctx->replace_ctx = new_ctx;
1182 	curr_ctx->replace_state = IEEE80211_CHANCTX_WILL_BE_REPLACED;
1183 
1184 	list_add_rcu(&new_ctx->list, &local->chanctx_list);
1185 
1186 	return new_ctx;
1187 }
1188 
1189 static bool
ieee80211_find_available_radio(struct ieee80211_local * local,const struct ieee80211_chan_req * chanreq,u32 radio_mask,int * radio_idx)1190 ieee80211_find_available_radio(struct ieee80211_local *local,
1191 			       const struct ieee80211_chan_req *chanreq,
1192 			       u32 radio_mask, int *radio_idx)
1193 {
1194 	struct wiphy *wiphy = local->hw.wiphy;
1195 	const struct wiphy_radio *radio;
1196 	int i;
1197 
1198 	*radio_idx = -1;
1199 	if (!wiphy->n_radio)
1200 		return true;
1201 
1202 	for (i = 0; i < wiphy->n_radio; i++) {
1203 		if (!(radio_mask & BIT(i)))
1204 			continue;
1205 
1206 		radio = &wiphy->radio[i];
1207 		if (!cfg80211_radio_chandef_valid(radio, &chanreq->oper))
1208 			continue;
1209 
1210 		if (!ieee80211_can_create_new_chanctx(local, i))
1211 			continue;
1212 
1213 		*radio_idx = i;
1214 		return true;
1215 	}
1216 
1217 	return false;
1218 }
1219 
ieee80211_link_reserve_chanctx(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode,bool radar_required)1220 int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
1221 				   const struct ieee80211_chan_req *chanreq,
1222 				   enum ieee80211_chanctx_mode mode,
1223 				   bool radar_required)
1224 {
1225 	struct ieee80211_sub_if_data *sdata = link->sdata;
1226 	struct ieee80211_local *local = sdata->local;
1227 	struct ieee80211_chanctx *new_ctx, *curr_ctx;
1228 	int radio_idx;
1229 
1230 	lockdep_assert_wiphy(local->hw.wiphy);
1231 
1232 	curr_ctx = ieee80211_link_get_chanctx(link);
1233 	if (curr_ctx && !local->ops->switch_vif_chanctx)
1234 		return -EOPNOTSUPP;
1235 
1236 	new_ctx = ieee80211_find_reservation_chanctx(local, chanreq, mode);
1237 	if (!new_ctx) {
1238 		if (ieee80211_can_create_new_chanctx(local, -1) &&
1239 		    ieee80211_find_available_radio(local, chanreq,
1240 						   sdata->wdev.radio_mask,
1241 						   &radio_idx))
1242 			new_ctx = ieee80211_new_chanctx(local, chanreq, mode,
1243 							false, radio_idx);
1244 		else
1245 			new_ctx = ieee80211_replace_chanctx(local, chanreq,
1246 							    mode, curr_ctx);
1247 		if (IS_ERR(new_ctx))
1248 			return PTR_ERR(new_ctx);
1249 	}
1250 
1251 	list_add(&link->reserved_chanctx_list, &new_ctx->reserved_links);
1252 	link->reserved_chanctx = new_ctx;
1253 	link->reserved = *chanreq;
1254 	link->reserved_radar_required = radar_required;
1255 	link->reserved_ready = false;
1256 
1257 	return 0;
1258 }
1259 
1260 static void
ieee80211_link_chanctx_reservation_complete(struct ieee80211_link_data * link)1261 ieee80211_link_chanctx_reservation_complete(struct ieee80211_link_data *link)
1262 {
1263 	struct ieee80211_sub_if_data *sdata = link->sdata;
1264 
1265 	switch (sdata->vif.type) {
1266 	case NL80211_IFTYPE_ADHOC:
1267 	case NL80211_IFTYPE_AP:
1268 	case NL80211_IFTYPE_MESH_POINT:
1269 	case NL80211_IFTYPE_OCB:
1270 		wiphy_work_queue(sdata->local->hw.wiphy,
1271 				 &link->csa.finalize_work);
1272 		break;
1273 	case NL80211_IFTYPE_STATION:
1274 		wiphy_delayed_work_queue(sdata->local->hw.wiphy,
1275 					 &link->u.mgd.csa.switch_work, 0);
1276 		break;
1277 	case NL80211_IFTYPE_UNSPECIFIED:
1278 	case NL80211_IFTYPE_AP_VLAN:
1279 	case NL80211_IFTYPE_WDS:
1280 	case NL80211_IFTYPE_MONITOR:
1281 	case NL80211_IFTYPE_P2P_CLIENT:
1282 	case NL80211_IFTYPE_P2P_GO:
1283 	case NL80211_IFTYPE_P2P_DEVICE:
1284 	case NL80211_IFTYPE_NAN:
1285 	case NUM_NL80211_IFTYPES:
1286 		WARN_ON(1);
1287 		break;
1288 	}
1289 }
1290 
1291 static void
ieee80211_link_update_chanreq(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq)1292 ieee80211_link_update_chanreq(struct ieee80211_link_data *link,
1293 			      const struct ieee80211_chan_req *chanreq)
1294 {
1295 	struct ieee80211_sub_if_data *sdata = link->sdata;
1296 	unsigned int link_id = link->link_id;
1297 	struct ieee80211_sub_if_data *vlan;
1298 
1299 	link->conf->chanreq = *chanreq;
1300 
1301 	if (sdata->vif.type != NL80211_IFTYPE_AP)
1302 		return;
1303 
1304 	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
1305 		struct ieee80211_bss_conf *vlan_conf;
1306 
1307 		vlan_conf = wiphy_dereference(sdata->local->hw.wiphy,
1308 					      vlan->vif.link_conf[link_id]);
1309 		if (WARN_ON(!vlan_conf))
1310 			continue;
1311 
1312 		vlan_conf->chanreq = *chanreq;
1313 	}
1314 }
1315 
1316 static int
ieee80211_link_use_reserved_reassign(struct ieee80211_link_data * link)1317 ieee80211_link_use_reserved_reassign(struct ieee80211_link_data *link)
1318 {
1319 	struct ieee80211_sub_if_data *sdata = link->sdata;
1320 	struct ieee80211_bss_conf *link_conf = link->conf;
1321 	struct ieee80211_local *local = sdata->local;
1322 	struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1323 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1324 	const struct ieee80211_chan_req *chanreq;
1325 	struct ieee80211_chan_req tmp;
1326 	u64 changed = 0;
1327 	int err;
1328 
1329 	lockdep_assert_wiphy(local->hw.wiphy);
1330 
1331 	new_ctx = link->reserved_chanctx;
1332 	old_ctx = ieee80211_link_get_chanctx(link);
1333 
1334 	if (WARN_ON(!link->reserved_ready))
1335 		return -EBUSY;
1336 
1337 	if (WARN_ON(!new_ctx))
1338 		return -EINVAL;
1339 
1340 	if (WARN_ON(!old_ctx))
1341 		return -EINVAL;
1342 
1343 	if (WARN_ON(new_ctx->replace_state ==
1344 		    IEEE80211_CHANCTX_REPLACES_OTHER))
1345 		return -EINVAL;
1346 
1347 	chanreq = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1348 							 &link->reserved,
1349 							 &tmp);
1350 	if (WARN_ON(!chanreq))
1351 		return -EINVAL;
1352 
1353 	if (link_conf->chanreq.oper.width != link->reserved.oper.width)
1354 		changed = BSS_CHANGED_BANDWIDTH;
1355 
1356 	ieee80211_link_update_chanreq(link, &link->reserved);
1357 
1358 	_ieee80211_change_chanctx(local, new_ctx, old_ctx, chanreq, link);
1359 
1360 	vif_chsw[0].vif = &sdata->vif;
1361 	vif_chsw[0].old_ctx = &old_ctx->conf;
1362 	vif_chsw[0].new_ctx = &new_ctx->conf;
1363 	vif_chsw[0].link_conf = link->conf;
1364 
1365 	list_del(&link->reserved_chanctx_list);
1366 	link->reserved_chanctx = NULL;
1367 
1368 	err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1369 				     CHANCTX_SWMODE_REASSIGN_VIF);
1370 	if (err) {
1371 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1372 			ieee80211_free_chanctx(local, new_ctx, false);
1373 
1374 		goto out;
1375 	}
1376 
1377 	list_move(&link->assigned_chanctx_list, &new_ctx->assigned_links);
1378 	rcu_assign_pointer(link_conf->chanctx_conf, &new_ctx->conf);
1379 
1380 	if (sdata->vif.type == NL80211_IFTYPE_AP)
1381 		__ieee80211_link_copy_chanctx_to_vlans(link, false);
1382 
1383 	ieee80211_check_fast_xmit_iface(sdata);
1384 
1385 	if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1386 		ieee80211_free_chanctx(local, old_ctx, false);
1387 
1388 	ieee80211_recalc_chanctx_min_def(local, new_ctx, NULL, false);
1389 	ieee80211_recalc_smps_chanctx(local, new_ctx);
1390 	ieee80211_recalc_radar_chanctx(local, new_ctx);
1391 
1392 	if (changed)
1393 		ieee80211_link_info_change_notify(sdata, link, changed);
1394 
1395 out:
1396 	ieee80211_link_chanctx_reservation_complete(link);
1397 	return err;
1398 }
1399 
1400 static int
ieee80211_link_use_reserved_assign(struct ieee80211_link_data * link)1401 ieee80211_link_use_reserved_assign(struct ieee80211_link_data *link)
1402 {
1403 	struct ieee80211_sub_if_data *sdata = link->sdata;
1404 	struct ieee80211_local *local = sdata->local;
1405 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1406 	const struct ieee80211_chan_req *chanreq;
1407 	struct ieee80211_chan_req tmp;
1408 	int err;
1409 
1410 	old_ctx = ieee80211_link_get_chanctx(link);
1411 	new_ctx = link->reserved_chanctx;
1412 
1413 	if (WARN_ON(!link->reserved_ready))
1414 		return -EINVAL;
1415 
1416 	if (WARN_ON(old_ctx))
1417 		return -EINVAL;
1418 
1419 	if (WARN_ON(!new_ctx))
1420 		return -EINVAL;
1421 
1422 	if (WARN_ON(new_ctx->replace_state ==
1423 		    IEEE80211_CHANCTX_REPLACES_OTHER))
1424 		return -EINVAL;
1425 
1426 	chanreq = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1427 							 &link->reserved,
1428 							 &tmp);
1429 	if (WARN_ON(!chanreq))
1430 		return -EINVAL;
1431 
1432 	ieee80211_change_chanctx(local, new_ctx, new_ctx, chanreq);
1433 
1434 	list_del(&link->reserved_chanctx_list);
1435 	link->reserved_chanctx = NULL;
1436 
1437 	err = ieee80211_assign_link_chanctx(link, new_ctx, false);
1438 	if (err) {
1439 		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1440 			ieee80211_free_chanctx(local, new_ctx, false);
1441 
1442 		goto out;
1443 	}
1444 
1445 out:
1446 	ieee80211_link_chanctx_reservation_complete(link);
1447 	return err;
1448 }
1449 
1450 static bool
ieee80211_link_has_in_place_reservation(struct ieee80211_link_data * link)1451 ieee80211_link_has_in_place_reservation(struct ieee80211_link_data *link)
1452 {
1453 	struct ieee80211_sub_if_data *sdata = link->sdata;
1454 	struct ieee80211_chanctx *old_ctx, *new_ctx;
1455 
1456 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1457 
1458 	new_ctx = link->reserved_chanctx;
1459 	old_ctx = ieee80211_link_get_chanctx(link);
1460 
1461 	if (!old_ctx)
1462 		return false;
1463 
1464 	if (WARN_ON(!new_ctx))
1465 		return false;
1466 
1467 	if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1468 		return false;
1469 
1470 	if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1471 		return false;
1472 
1473 	return true;
1474 }
1475 
ieee80211_chsw_switch_vifs(struct ieee80211_local * local,int n_vifs)1476 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1477 				      int n_vifs)
1478 {
1479 	struct ieee80211_vif_chanctx_switch *vif_chsw;
1480 	struct ieee80211_link_data *link;
1481 	struct ieee80211_chanctx *ctx, *old_ctx;
1482 	int i, err;
1483 
1484 	lockdep_assert_wiphy(local->hw.wiphy);
1485 
1486 	vif_chsw = kcalloc(n_vifs, sizeof(vif_chsw[0]), GFP_KERNEL);
1487 	if (!vif_chsw)
1488 		return -ENOMEM;
1489 
1490 	i = 0;
1491 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1492 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1493 			continue;
1494 
1495 		if (WARN_ON(!ctx->replace_ctx)) {
1496 			err = -EINVAL;
1497 			goto out;
1498 		}
1499 
1500 		list_for_each_entry(link, &ctx->reserved_links,
1501 				    reserved_chanctx_list) {
1502 			if (!ieee80211_link_has_in_place_reservation(link))
1503 				continue;
1504 
1505 			old_ctx = ieee80211_link_get_chanctx(link);
1506 			vif_chsw[i].vif = &link->sdata->vif;
1507 			vif_chsw[i].old_ctx = &old_ctx->conf;
1508 			vif_chsw[i].new_ctx = &ctx->conf;
1509 			vif_chsw[i].link_conf = link->conf;
1510 
1511 			i++;
1512 		}
1513 	}
1514 
1515 	err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1516 				     CHANCTX_SWMODE_SWAP_CONTEXTS);
1517 
1518 out:
1519 	kfree(vif_chsw);
1520 	return err;
1521 }
1522 
ieee80211_chsw_switch_ctxs(struct ieee80211_local * local)1523 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1524 {
1525 	struct ieee80211_chanctx *ctx;
1526 	int err;
1527 
1528 	lockdep_assert_wiphy(local->hw.wiphy);
1529 
1530 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1531 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1532 			continue;
1533 
1534 		if (!list_empty(&ctx->replace_ctx->assigned_links))
1535 			continue;
1536 
1537 		ieee80211_del_chanctx(local, ctx->replace_ctx, false);
1538 		err = ieee80211_add_chanctx(local, ctx);
1539 		if (err)
1540 			goto err;
1541 	}
1542 
1543 	return 0;
1544 
1545 err:
1546 	WARN_ON(ieee80211_add_chanctx(local, ctx));
1547 	list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1548 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1549 			continue;
1550 
1551 		if (!list_empty(&ctx->replace_ctx->assigned_links))
1552 			continue;
1553 
1554 		ieee80211_del_chanctx(local, ctx, false);
1555 		WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1556 	}
1557 
1558 	return err;
1559 }
1560 
ieee80211_vif_use_reserved_switch(struct ieee80211_local * local)1561 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1562 {
1563 	struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1564 	int err, n_assigned, n_reserved, n_ready;
1565 	int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1566 
1567 	lockdep_assert_wiphy(local->hw.wiphy);
1568 
1569 	/*
1570 	 * If there are 2 independent pairs of channel contexts performing
1571 	 * cross-switch of their vifs this code will still wait until both are
1572 	 * ready even though it could be possible to switch one before the
1573 	 * other is ready.
1574 	 *
1575 	 * For practical reasons and code simplicity just do a single huge
1576 	 * switch.
1577 	 */
1578 
1579 	/*
1580 	 * Verify if the reservation is still feasible.
1581 	 *  - if it's not then disconnect
1582 	 *  - if it is but not all vifs necessary are ready then defer
1583 	 */
1584 
1585 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1586 		struct ieee80211_link_data *link;
1587 
1588 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1589 			continue;
1590 
1591 		if (WARN_ON(!ctx->replace_ctx)) {
1592 			err = -EINVAL;
1593 			goto err;
1594 		}
1595 
1596 		n_ctx++;
1597 
1598 		n_assigned = 0;
1599 		n_reserved = 0;
1600 		n_ready = 0;
1601 
1602 		list_for_each_entry(link, &ctx->replace_ctx->assigned_links,
1603 				    assigned_chanctx_list) {
1604 			n_assigned++;
1605 			if (link->reserved_chanctx) {
1606 				n_reserved++;
1607 				if (link->reserved_ready)
1608 					n_ready++;
1609 			}
1610 		}
1611 
1612 		if (n_assigned != n_reserved) {
1613 			if (n_ready == n_reserved) {
1614 				wiphy_info(local->hw.wiphy,
1615 					   "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1616 				err = -EBUSY;
1617 				goto err;
1618 			}
1619 
1620 			return -EAGAIN;
1621 		}
1622 
1623 		ctx->conf.radar_enabled = false;
1624 		list_for_each_entry(link, &ctx->reserved_links,
1625 				    reserved_chanctx_list) {
1626 			if (ieee80211_link_has_in_place_reservation(link) &&
1627 			    !link->reserved_ready)
1628 				return -EAGAIN;
1629 
1630 			old_ctx = ieee80211_link_get_chanctx(link);
1631 			if (old_ctx) {
1632 				if (old_ctx->replace_state ==
1633 				    IEEE80211_CHANCTX_WILL_BE_REPLACED)
1634 					n_vifs_switch++;
1635 				else
1636 					n_vifs_assign++;
1637 			} else {
1638 				n_vifs_ctxless++;
1639 			}
1640 
1641 			if (link->reserved_radar_required)
1642 				ctx->conf.radar_enabled = true;
1643 		}
1644 	}
1645 
1646 	if (WARN_ON(n_ctx == 0) ||
1647 	    WARN_ON(n_vifs_switch == 0 &&
1648 		    n_vifs_assign == 0 &&
1649 		    n_vifs_ctxless == 0)) {
1650 		err = -EINVAL;
1651 		goto err;
1652 	}
1653 
1654 	/* update station rate control and min width before switch */
1655 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1656 		struct ieee80211_link_data *link;
1657 
1658 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1659 			continue;
1660 
1661 		if (WARN_ON(!ctx->replace_ctx)) {
1662 			err = -EINVAL;
1663 			goto err;
1664 		}
1665 
1666 		list_for_each_entry(link, &ctx->reserved_links,
1667 				    reserved_chanctx_list) {
1668 			if (!ieee80211_link_has_in_place_reservation(link))
1669 				continue;
1670 
1671 			ieee80211_chan_bw_change(local,
1672 						 ieee80211_link_get_chanctx(link),
1673 						 true, true);
1674 		}
1675 
1676 		ieee80211_recalc_chanctx_min_def(local, ctx, NULL, true);
1677 	}
1678 
1679 	/*
1680 	 * All necessary vifs are ready. Perform the switch now depending on
1681 	 * reservations and driver capabilities.
1682 	 */
1683 
1684 	if (n_vifs_switch > 0) {
1685 		err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1686 		if (err)
1687 			goto err;
1688 	}
1689 
1690 	if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1691 		err = ieee80211_chsw_switch_ctxs(local);
1692 		if (err)
1693 			goto err;
1694 	}
1695 
1696 	/*
1697 	 * Update all structures, values and pointers to point to new channel
1698 	 * context(s).
1699 	 */
1700 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1701 		struct ieee80211_link_data *link, *link_tmp;
1702 
1703 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1704 			continue;
1705 
1706 		if (WARN_ON(!ctx->replace_ctx)) {
1707 			err = -EINVAL;
1708 			goto err;
1709 		}
1710 
1711 		list_for_each_entry(link, &ctx->reserved_links,
1712 				    reserved_chanctx_list) {
1713 			struct ieee80211_sub_if_data *sdata = link->sdata;
1714 			struct ieee80211_bss_conf *link_conf = link->conf;
1715 			u64 changed = 0;
1716 
1717 			if (!ieee80211_link_has_in_place_reservation(link))
1718 				continue;
1719 
1720 			rcu_assign_pointer(link_conf->chanctx_conf,
1721 					   &ctx->conf);
1722 
1723 			if (sdata->vif.type == NL80211_IFTYPE_AP)
1724 				__ieee80211_link_copy_chanctx_to_vlans(link,
1725 								       false);
1726 
1727 			ieee80211_check_fast_xmit_iface(sdata);
1728 
1729 			link->radar_required = link->reserved_radar_required;
1730 
1731 			if (link_conf->chanreq.oper.width != link->reserved.oper.width)
1732 				changed = BSS_CHANGED_BANDWIDTH;
1733 
1734 			ieee80211_link_update_chanreq(link, &link->reserved);
1735 			if (changed)
1736 				ieee80211_link_info_change_notify(sdata,
1737 								  link,
1738 								  changed);
1739 
1740 			ieee80211_recalc_txpower(link, false);
1741 		}
1742 
1743 		ieee80211_recalc_chanctx_chantype(local, ctx);
1744 		ieee80211_recalc_smps_chanctx(local, ctx);
1745 		ieee80211_recalc_radar_chanctx(local, ctx);
1746 		ieee80211_recalc_chanctx_min_def(local, ctx, NULL, false);
1747 
1748 		list_for_each_entry_safe(link, link_tmp, &ctx->reserved_links,
1749 					 reserved_chanctx_list) {
1750 			if (ieee80211_link_get_chanctx(link) != ctx)
1751 				continue;
1752 
1753 			list_del(&link->reserved_chanctx_list);
1754 			list_move(&link->assigned_chanctx_list,
1755 				  &ctx->assigned_links);
1756 			link->reserved_chanctx = NULL;
1757 
1758 			ieee80211_link_chanctx_reservation_complete(link);
1759 			ieee80211_chan_bw_change(local, ctx, false, false);
1760 		}
1761 
1762 		/*
1763 		 * This context might have been a dependency for an already
1764 		 * ready re-assign reservation interface that was deferred. Do
1765 		 * not propagate error to the caller though. The in-place
1766 		 * reservation for originally requested interface has already
1767 		 * succeeded at this point.
1768 		 */
1769 		list_for_each_entry_safe(link, link_tmp, &ctx->reserved_links,
1770 					 reserved_chanctx_list) {
1771 			if (WARN_ON(ieee80211_link_has_in_place_reservation(link)))
1772 				continue;
1773 
1774 			if (WARN_ON(link->reserved_chanctx != ctx))
1775 				continue;
1776 
1777 			if (!link->reserved_ready)
1778 				continue;
1779 
1780 			if (ieee80211_link_get_chanctx(link))
1781 				err = ieee80211_link_use_reserved_reassign(link);
1782 			else
1783 				err = ieee80211_link_use_reserved_assign(link);
1784 
1785 			if (err) {
1786 				link_info(link,
1787 					  "failed to finalize (re-)assign reservation (err=%d)\n",
1788 					  err);
1789 				ieee80211_link_unreserve_chanctx(link);
1790 				cfg80211_stop_iface(local->hw.wiphy,
1791 						    &link->sdata->wdev,
1792 						    GFP_KERNEL);
1793 			}
1794 		}
1795 	}
1796 
1797 	/*
1798 	 * Finally free old contexts
1799 	 */
1800 
1801 	list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1802 		if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1803 			continue;
1804 
1805 		ctx->replace_ctx->replace_ctx = NULL;
1806 		ctx->replace_ctx->replace_state =
1807 				IEEE80211_CHANCTX_REPLACE_NONE;
1808 
1809 		list_del_rcu(&ctx->list);
1810 		kfree_rcu(ctx, rcu_head);
1811 	}
1812 
1813 	return 0;
1814 
1815 err:
1816 	list_for_each_entry(ctx, &local->chanctx_list, list) {
1817 		struct ieee80211_link_data *link, *link_tmp;
1818 
1819 		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1820 			continue;
1821 
1822 		list_for_each_entry_safe(link, link_tmp, &ctx->reserved_links,
1823 					 reserved_chanctx_list) {
1824 			ieee80211_link_unreserve_chanctx(link);
1825 			ieee80211_link_chanctx_reservation_complete(link);
1826 		}
1827 	}
1828 
1829 	return err;
1830 }
1831 
__ieee80211_link_release_channel(struct ieee80211_link_data * link,bool skip_idle_recalc)1832 void __ieee80211_link_release_channel(struct ieee80211_link_data *link,
1833 				      bool skip_idle_recalc)
1834 {
1835 	struct ieee80211_sub_if_data *sdata = link->sdata;
1836 	struct ieee80211_bss_conf *link_conf = link->conf;
1837 	struct ieee80211_local *local = sdata->local;
1838 	struct ieee80211_chanctx_conf *conf;
1839 	struct ieee80211_chanctx *ctx;
1840 	bool use_reserved_switch = false;
1841 
1842 	lockdep_assert_wiphy(local->hw.wiphy);
1843 
1844 	conf = rcu_dereference_protected(link_conf->chanctx_conf,
1845 					 lockdep_is_held(&local->hw.wiphy->mtx));
1846 	if (!conf)
1847 		return;
1848 
1849 	ctx = container_of(conf, struct ieee80211_chanctx, conf);
1850 
1851 	if (link->reserved_chanctx) {
1852 		if (link->reserved_chanctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER &&
1853 		    ieee80211_chanctx_num_reserved(local, link->reserved_chanctx) > 1)
1854 			use_reserved_switch = true;
1855 
1856 		ieee80211_link_unreserve_chanctx(link);
1857 	}
1858 
1859 	ieee80211_assign_link_chanctx(link, NULL, false);
1860 	if (ieee80211_chanctx_refcount(local, ctx) == 0)
1861 		ieee80211_free_chanctx(local, ctx, skip_idle_recalc);
1862 
1863 	link->radar_required = false;
1864 
1865 	/* Unreserving may ready an in-place reservation. */
1866 	if (use_reserved_switch)
1867 		ieee80211_vif_use_reserved_switch(local);
1868 }
1869 
_ieee80211_link_use_channel(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq,enum ieee80211_chanctx_mode mode,bool assign_on_failure)1870 int _ieee80211_link_use_channel(struct ieee80211_link_data *link,
1871 				const struct ieee80211_chan_req *chanreq,
1872 				enum ieee80211_chanctx_mode mode,
1873 				bool assign_on_failure)
1874 {
1875 	struct ieee80211_sub_if_data *sdata = link->sdata;
1876 	struct ieee80211_local *local = sdata->local;
1877 	struct ieee80211_chanctx *ctx;
1878 	u8 radar_detect_width = 0;
1879 	bool reserved = false;
1880 	int radio_idx;
1881 	int ret;
1882 
1883 	lockdep_assert_wiphy(local->hw.wiphy);
1884 
1885 	if (!ieee80211_vif_link_active(&sdata->vif, link->link_id)) {
1886 		ieee80211_link_update_chanreq(link, chanreq);
1887 		return 0;
1888 	}
1889 
1890 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1891 					    &chanreq->oper,
1892 					    sdata->wdev.iftype);
1893 	if (ret < 0)
1894 		goto out;
1895 	if (ret > 0)
1896 		radar_detect_width = BIT(chanreq->oper.width);
1897 
1898 	link->radar_required = ret;
1899 
1900 	ret = ieee80211_check_combinations(sdata, &chanreq->oper, mode,
1901 					   radar_detect_width, -1);
1902 	if (ret < 0)
1903 		goto out;
1904 
1905 	__ieee80211_link_release_channel(link, false);
1906 
1907 	ctx = ieee80211_find_chanctx(local, link, chanreq, mode);
1908 	/* Note: context is now reserved */
1909 	if (ctx)
1910 		reserved = true;
1911 	else if (!ieee80211_find_available_radio(local, chanreq,
1912 						 sdata->wdev.radio_mask,
1913 						 &radio_idx))
1914 		ctx = ERR_PTR(-EBUSY);
1915 	else
1916 		ctx = ieee80211_new_chanctx(local, chanreq, mode,
1917 					    assign_on_failure, radio_idx);
1918 	if (IS_ERR(ctx)) {
1919 		ret = PTR_ERR(ctx);
1920 		goto out;
1921 	}
1922 
1923 	ieee80211_link_update_chanreq(link, chanreq);
1924 
1925 	ret = ieee80211_assign_link_chanctx(link, ctx, assign_on_failure);
1926 
1927 	if (reserved) {
1928 		/* remove reservation */
1929 		WARN_ON(link->reserved_chanctx != ctx);
1930 		link->reserved_chanctx = NULL;
1931 		list_del(&link->reserved_chanctx_list);
1932 	}
1933 
1934 	if (ret) {
1935 		/* if assign fails refcount stays the same */
1936 		if (ieee80211_chanctx_refcount(local, ctx) == 0)
1937 			ieee80211_free_chanctx(local, ctx, false);
1938 		goto out;
1939 	}
1940 
1941 	ieee80211_recalc_smps_chanctx(local, ctx);
1942 	ieee80211_recalc_radar_chanctx(local, ctx);
1943  out:
1944 	if (ret)
1945 		link->radar_required = false;
1946 
1947 	return ret;
1948 }
1949 
ieee80211_link_use_reserved_context(struct ieee80211_link_data * link)1950 int ieee80211_link_use_reserved_context(struct ieee80211_link_data *link)
1951 {
1952 	struct ieee80211_sub_if_data *sdata = link->sdata;
1953 	struct ieee80211_local *local = sdata->local;
1954 	struct ieee80211_chanctx *new_ctx;
1955 	struct ieee80211_chanctx *old_ctx;
1956 	int err;
1957 
1958 	lockdep_assert_wiphy(local->hw.wiphy);
1959 
1960 	new_ctx = link->reserved_chanctx;
1961 	old_ctx = ieee80211_link_get_chanctx(link);
1962 
1963 	if (WARN_ON(!new_ctx))
1964 		return -EINVAL;
1965 
1966 	if (WARN_ON(new_ctx->replace_state ==
1967 		    IEEE80211_CHANCTX_WILL_BE_REPLACED))
1968 		return -EINVAL;
1969 
1970 	if (WARN_ON(link->reserved_ready))
1971 		return -EINVAL;
1972 
1973 	link->reserved_ready = true;
1974 
1975 	if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1976 		if (old_ctx)
1977 			return ieee80211_link_use_reserved_reassign(link);
1978 
1979 		return ieee80211_link_use_reserved_assign(link);
1980 	}
1981 
1982 	/*
1983 	 * In-place reservation may need to be finalized now either if:
1984 	 *  a) sdata is taking part in the swapping itself and is the last one
1985 	 *  b) sdata has switched with a re-assign reservation to an existing
1986 	 *     context readying in-place switching of old_ctx
1987 	 *
1988 	 * In case of (b) do not propagate the error up because the requested
1989 	 * sdata already switched successfully. Just spill an extra warning.
1990 	 * The ieee80211_vif_use_reserved_switch() already stops all necessary
1991 	 * interfaces upon failure.
1992 	 */
1993 	if ((old_ctx &&
1994 	     old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1995 	    new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1996 		err = ieee80211_vif_use_reserved_switch(local);
1997 		if (err && err != -EAGAIN) {
1998 			if (new_ctx->replace_state ==
1999 			    IEEE80211_CHANCTX_REPLACES_OTHER)
2000 				return err;
2001 
2002 			wiphy_info(local->hw.wiphy,
2003 				   "depending in-place reservation failed (err=%d)\n",
2004 				   err);
2005 		}
2006 	}
2007 
2008 	return 0;
2009 }
2010 
2011 /*
2012  * This is similar to ieee80211_chanctx_compatible(), but rechecks
2013  * against all the links actually using it (except the one that's
2014  * passed, since that one is changing).
2015  * This is done in order to allow changes to the AP's bandwidth for
2016  * wider bandwidth OFDMA purposes, which wouldn't be treated as
2017  * compatible by ieee80211_chanctx_recheck() but is OK if the link
2018  * requesting the update is the only one using it.
2019  */
2020 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)2021 ieee80211_chanctx_recheck(struct ieee80211_local *local,
2022 			  struct ieee80211_link_data *skip_link,
2023 			  struct ieee80211_chanctx *ctx,
2024 			  const struct ieee80211_chan_req *req,
2025 			  struct ieee80211_chan_req *tmp)
2026 {
2027 	const struct ieee80211_chan_req *ret = req;
2028 	struct ieee80211_link_data *link;
2029 
2030 	lockdep_assert_wiphy(local->hw.wiphy);
2031 
2032 	for_each_sdata_link(local, link) {
2033 		if (link == skip_link)
2034 			continue;
2035 
2036 		if (rcu_access_pointer(link->conf->chanctx_conf) == &ctx->conf) {
2037 			ret = ieee80211_chanreq_compatible(ret,
2038 							   &link->conf->chanreq,
2039 							   tmp);
2040 			if (!ret)
2041 				return NULL;
2042 		}
2043 
2044 		if (link->reserved_chanctx == ctx) {
2045 			ret = ieee80211_chanreq_compatible(ret,
2046 							   &link->reserved,
2047 							   tmp);
2048 			if (!ret)
2049 				return NULL;
2050 		}
2051 	}
2052 
2053 	*tmp = *ret;
2054 	return tmp;
2055 }
2056 
ieee80211_link_change_chanreq(struct ieee80211_link_data * link,const struct ieee80211_chan_req * chanreq,u64 * changed)2057 int ieee80211_link_change_chanreq(struct ieee80211_link_data *link,
2058 				  const struct ieee80211_chan_req *chanreq,
2059 				  u64 *changed)
2060 {
2061 	struct ieee80211_sub_if_data *sdata = link->sdata;
2062 	struct ieee80211_bss_conf *link_conf = link->conf;
2063 	struct ieee80211_local *local = sdata->local;
2064 	struct ieee80211_chanctx_conf *conf;
2065 	struct ieee80211_chanctx *ctx;
2066 	const struct ieee80211_chan_req *compat;
2067 	struct ieee80211_chan_req tmp;
2068 
2069 	lockdep_assert_wiphy(local->hw.wiphy);
2070 
2071 	if (!cfg80211_chandef_usable(sdata->local->hw.wiphy,
2072 				     &chanreq->oper,
2073 				     IEEE80211_CHAN_DISABLED))
2074 		return -EINVAL;
2075 
2076 	/* for non-HT 20 MHz the rest doesn't matter */
2077 	if (chanreq->oper.width == NL80211_CHAN_WIDTH_20_NOHT &&
2078 	    cfg80211_chandef_identical(&chanreq->oper, &link_conf->chanreq.oper))
2079 		return 0;
2080 
2081 	/* but you cannot switch to/from it */
2082 	if (chanreq->oper.width == NL80211_CHAN_WIDTH_20_NOHT ||
2083 	    link_conf->chanreq.oper.width == NL80211_CHAN_WIDTH_20_NOHT)
2084 		return -EINVAL;
2085 
2086 	conf = rcu_dereference_protected(link_conf->chanctx_conf,
2087 					 lockdep_is_held(&local->hw.wiphy->mtx));
2088 	if (!conf)
2089 		return -EINVAL;
2090 
2091 	ctx = container_of(conf, struct ieee80211_chanctx, conf);
2092 
2093 	compat = ieee80211_chanctx_recheck(local, link, ctx, chanreq, &tmp);
2094 	if (!compat)
2095 		return -EINVAL;
2096 
2097 	switch (ctx->replace_state) {
2098 	case IEEE80211_CHANCTX_REPLACE_NONE:
2099 		if (!ieee80211_chanctx_reserved_chanreq(local, ctx, compat,
2100 							&tmp))
2101 			return -EBUSY;
2102 		break;
2103 	case IEEE80211_CHANCTX_WILL_BE_REPLACED:
2104 		/* TODO: Perhaps the bandwidth change could be treated as a
2105 		 * reservation itself? */
2106 		return -EBUSY;
2107 	case IEEE80211_CHANCTX_REPLACES_OTHER:
2108 		/* channel context that is going to replace another channel
2109 		 * context doesn't really exist and shouldn't be assigned
2110 		 * anywhere yet */
2111 		WARN_ON(1);
2112 		break;
2113 	}
2114 
2115 	ieee80211_link_update_chanreq(link, chanreq);
2116 
2117 	ieee80211_recalc_chanctx_chantype(local, ctx);
2118 
2119 	*changed |= BSS_CHANGED_BANDWIDTH;
2120 	return 0;
2121 }
2122 
ieee80211_link_release_channel(struct ieee80211_link_data * link)2123 void ieee80211_link_release_channel(struct ieee80211_link_data *link)
2124 {
2125 	struct ieee80211_sub_if_data *sdata = link->sdata;
2126 
2127 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
2128 
2129 	if (rcu_access_pointer(link->conf->chanctx_conf))
2130 		__ieee80211_link_release_channel(link, false);
2131 }
2132 
ieee80211_link_vlan_copy_chanctx(struct ieee80211_link_data * link)2133 void ieee80211_link_vlan_copy_chanctx(struct ieee80211_link_data *link)
2134 {
2135 	struct ieee80211_sub_if_data *sdata = link->sdata;
2136 	unsigned int link_id = link->link_id;
2137 	struct ieee80211_bss_conf *link_conf = link->conf;
2138 	struct ieee80211_bss_conf *ap_conf;
2139 	struct ieee80211_local *local = sdata->local;
2140 	struct ieee80211_sub_if_data *ap;
2141 	struct ieee80211_chanctx_conf *conf;
2142 
2143 	lockdep_assert_wiphy(local->hw.wiphy);
2144 
2145 	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
2146 		return;
2147 
2148 	ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
2149 
2150 	ap_conf = wiphy_dereference(local->hw.wiphy,
2151 				    ap->vif.link_conf[link_id]);
2152 	conf = wiphy_dereference(local->hw.wiphy,
2153 				 ap_conf->chanctx_conf);
2154 	rcu_assign_pointer(link_conf->chanctx_conf, conf);
2155 }
2156 
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)2157 void ieee80211_iter_chan_contexts_atomic(
2158 	struct ieee80211_hw *hw,
2159 	void (*iter)(struct ieee80211_hw *hw,
2160 		     struct ieee80211_chanctx_conf *chanctx_conf,
2161 		     void *data),
2162 	void *iter_data)
2163 {
2164 	struct ieee80211_local *local = hw_to_local(hw);
2165 	struct ieee80211_chanctx *ctx;
2166 
2167 	rcu_read_lock();
2168 	list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
2169 		if (ctx->driver_present)
2170 			iter(hw, &ctx->conf, iter_data);
2171 	rcu_read_unlock();
2172 }
2173 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);
2174