Merge commit 'c1e140bf79d817d4a7aa9932eb98b0359c87af33' from mac80211-next
[cascardo/linux.git] / net / mac80211 / chan.c
1 /*
2  * mac80211 - channel management
3  */
4
5 #include <linux/nl80211.h>
6 #include <linux/export.h>
7 #include <linux/rtnetlink.h>
8 #include <net/cfg80211.h>
9 #include "ieee80211_i.h"
10 #include "driver-ops.h"
11
12 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
13                                           struct ieee80211_chanctx *ctx)
14 {
15         struct ieee80211_sub_if_data *sdata;
16         int num = 0;
17
18         lockdep_assert_held(&local->chanctx_mtx);
19
20         list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
21                 num++;
22
23         return num;
24 }
25
26 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
27                                           struct ieee80211_chanctx *ctx)
28 {
29         struct ieee80211_sub_if_data *sdata;
30         int num = 0;
31
32         lockdep_assert_held(&local->chanctx_mtx);
33
34         list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
35                 num++;
36
37         return num;
38 }
39
40 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
41                                struct ieee80211_chanctx *ctx)
42 {
43         return ieee80211_chanctx_num_assigned(local, ctx) +
44                ieee80211_chanctx_num_reserved(local, ctx);
45 }
46
47 static int ieee80211_num_chanctx(struct ieee80211_local *local)
48 {
49         struct ieee80211_chanctx *ctx;
50         int num = 0;
51
52         lockdep_assert_held(&local->chanctx_mtx);
53
54         list_for_each_entry(ctx, &local->chanctx_list, list)
55                 num++;
56
57         return num;
58 }
59
60 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
61 {
62         lockdep_assert_held(&local->chanctx_mtx);
63         return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
64 }
65
66 static struct ieee80211_chanctx *
67 ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
68 {
69         struct ieee80211_local *local __maybe_unused = sdata->local;
70         struct ieee80211_chanctx_conf *conf;
71
72         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
73                                          lockdep_is_held(&local->chanctx_mtx));
74         if (!conf)
75                 return NULL;
76
77         return container_of(conf, struct ieee80211_chanctx, conf);
78 }
79
80 static const struct cfg80211_chan_def *
81 ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
82                                    struct ieee80211_chanctx *ctx,
83                                    const struct cfg80211_chan_def *compat)
84 {
85         struct ieee80211_sub_if_data *sdata;
86
87         lockdep_assert_held(&local->chanctx_mtx);
88
89         list_for_each_entry(sdata, &ctx->reserved_vifs,
90                             reserved_chanctx_list) {
91                 if (!compat)
92                         compat = &sdata->reserved_chandef;
93
94                 compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
95                                                      compat);
96                 if (!compat)
97                         break;
98         }
99
100         return compat;
101 }
102
103 static const struct cfg80211_chan_def *
104 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
105                                        struct ieee80211_chanctx *ctx,
106                                        const struct cfg80211_chan_def *compat)
107 {
108         struct ieee80211_sub_if_data *sdata;
109
110         lockdep_assert_held(&local->chanctx_mtx);
111
112         list_for_each_entry(sdata, &ctx->assigned_vifs,
113                             assigned_chanctx_list) {
114                 if (sdata->reserved_chanctx != NULL)
115                         continue;
116
117                 if (!compat)
118                         compat = &sdata->vif.bss_conf.chandef;
119
120                 compat = cfg80211_chandef_compatible(
121                                 &sdata->vif.bss_conf.chandef, compat);
122                 if (!compat)
123                         break;
124         }
125
126         return compat;
127 }
128
129 static const struct cfg80211_chan_def *
130 ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
131                                    struct ieee80211_chanctx *ctx,
132                                    const struct cfg80211_chan_def *compat)
133 {
134         lockdep_assert_held(&local->chanctx_mtx);
135
136         compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
137         if (!compat)
138                 return NULL;
139
140         compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
141         if (!compat)
142                 return NULL;
143
144         return compat;
145 }
146
147 static bool
148 ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
149                                       struct ieee80211_chanctx *ctx,
150                                       const struct cfg80211_chan_def *def)
151 {
152         lockdep_assert_held(&local->chanctx_mtx);
153
154         if (ieee80211_chanctx_combined_chandef(local, ctx, def))
155                 return true;
156
157         if (!list_empty(&ctx->reserved_vifs) &&
158             ieee80211_chanctx_reserved_chandef(local, ctx, def))
159                 return true;
160
161         return false;
162 }
163
164 static struct ieee80211_chanctx *
165 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
166                                    const struct cfg80211_chan_def *chandef,
167                                    enum ieee80211_chanctx_mode mode)
168 {
169         struct ieee80211_chanctx *ctx;
170
171         lockdep_assert_held(&local->chanctx_mtx);
172
173         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
174                 return NULL;
175
176         list_for_each_entry(ctx, &local->chanctx_list, list) {
177                 if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
178                         continue;
179
180                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
181                         continue;
182
183                 if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
184                                                            chandef))
185                         continue;
186
187                 return ctx;
188         }
189
190         return NULL;
191 }
192
193 static enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
194 {
195         switch (sta->bandwidth) {
196         case IEEE80211_STA_RX_BW_20:
197                 if (sta->ht_cap.ht_supported)
198                         return NL80211_CHAN_WIDTH_20;
199                 else
200                         return NL80211_CHAN_WIDTH_20_NOHT;
201         case IEEE80211_STA_RX_BW_40:
202                 return NL80211_CHAN_WIDTH_40;
203         case IEEE80211_STA_RX_BW_80:
204                 return NL80211_CHAN_WIDTH_80;
205         case IEEE80211_STA_RX_BW_160:
206                 /*
207                  * This applied for both 160 and 80+80. since we use
208                  * the returned value to consider degradation of
209                  * ctx->conf.min_def, we have to make sure to take
210                  * the bigger one (NL80211_CHAN_WIDTH_160).
211                  * Otherwise we might try degrading even when not
212                  * needed, as the max required sta_bw returned (80+80)
213                  * might be smaller than the configured bw (160).
214                  */
215                 return NL80211_CHAN_WIDTH_160;
216         default:
217                 WARN_ON(1);
218                 return NL80211_CHAN_WIDTH_20;
219         }
220 }
221
222 static enum nl80211_chan_width
223 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
224 {
225         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
226         struct sta_info *sta;
227
228         rcu_read_lock();
229         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
230                 if (sdata != sta->sdata &&
231                     !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
232                         continue;
233
234                 if (!sta->uploaded)
235                         continue;
236
237                 max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
238         }
239         rcu_read_unlock();
240
241         return max_bw;
242 }
243
244 static enum nl80211_chan_width
245 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
246                                       struct ieee80211_chanctx_conf *conf)
247 {
248         struct ieee80211_sub_if_data *sdata;
249         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
250
251         rcu_read_lock();
252         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
253                 struct ieee80211_vif *vif = &sdata->vif;
254                 enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
255
256                 if (!ieee80211_sdata_running(sdata))
257                         continue;
258
259                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
260                         continue;
261
262                 switch (vif->type) {
263                 case NL80211_IFTYPE_AP:
264                 case NL80211_IFTYPE_AP_VLAN:
265                         width = ieee80211_get_max_required_bw(sdata);
266                         break;
267                 case NL80211_IFTYPE_P2P_DEVICE:
268                         continue;
269                 case NL80211_IFTYPE_STATION:
270                 case NL80211_IFTYPE_ADHOC:
271                 case NL80211_IFTYPE_WDS:
272                 case NL80211_IFTYPE_MESH_POINT:
273                 case NL80211_IFTYPE_OCB:
274                         width = vif->bss_conf.chandef.width;
275                         break;
276                 case NL80211_IFTYPE_UNSPECIFIED:
277                 case NUM_NL80211_IFTYPES:
278                 case NL80211_IFTYPE_MONITOR:
279                 case NL80211_IFTYPE_P2P_CLIENT:
280                 case NL80211_IFTYPE_P2P_GO:
281                         WARN_ON_ONCE(1);
282                 }
283                 max_bw = max(max_bw, width);
284         }
285
286         /* use the configured bandwidth in case of monitor interface */
287         sdata = rcu_dereference(local->monitor_sdata);
288         if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
289                 max_bw = max(max_bw, conf->def.width);
290
291         rcu_read_unlock();
292
293         return max_bw;
294 }
295
296 /*
297  * recalc the min required chan width of the channel context, which is
298  * the max of min required widths of all the interfaces bound to this
299  * channel context.
300  */
301 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
302                                       struct ieee80211_chanctx *ctx)
303 {
304         enum nl80211_chan_width max_bw;
305         struct cfg80211_chan_def min_def;
306
307         lockdep_assert_held(&local->chanctx_mtx);
308
309         /* don't optimize 5MHz, 10MHz, and radar_enabled confs */
310         if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
311             ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
312             ctx->conf.radar_enabled) {
313                 ctx->conf.min_def = ctx->conf.def;
314                 return;
315         }
316
317         max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
318
319         /* downgrade chandef up to max_bw */
320         min_def = ctx->conf.def;
321         while (min_def.width > max_bw)
322                 ieee80211_chandef_downgrade(&min_def);
323
324         if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
325                 return;
326
327         ctx->conf.min_def = min_def;
328         if (!ctx->driver_present)
329                 return;
330
331         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
332 }
333
334 static void ieee80211_change_chanctx(struct ieee80211_local *local,
335                                      struct ieee80211_chanctx *ctx,
336                                      const struct cfg80211_chan_def *chandef)
337 {
338         if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
339                 return;
340
341         WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
342
343         ctx->conf.def = *chandef;
344         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
345         ieee80211_recalc_chanctx_min_def(local, ctx);
346
347         if (!local->use_chanctx) {
348                 local->_oper_chandef = *chandef;
349                 ieee80211_hw_config(local, 0);
350         }
351 }
352
353 static struct ieee80211_chanctx *
354 ieee80211_find_chanctx(struct ieee80211_local *local,
355                        const struct cfg80211_chan_def *chandef,
356                        enum ieee80211_chanctx_mode mode)
357 {
358         struct ieee80211_chanctx *ctx;
359
360         lockdep_assert_held(&local->chanctx_mtx);
361
362         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
363                 return NULL;
364
365         list_for_each_entry(ctx, &local->chanctx_list, list) {
366                 const struct cfg80211_chan_def *compat;
367
368                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
369                         continue;
370
371                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
372                         continue;
373
374                 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
375                 if (!compat)
376                         continue;
377
378                 compat = ieee80211_chanctx_reserved_chandef(local, ctx,
379                                                             compat);
380                 if (!compat)
381                         continue;
382
383                 ieee80211_change_chanctx(local, ctx, compat);
384
385                 return ctx;
386         }
387
388         return NULL;
389 }
390
391 bool ieee80211_is_radar_required(struct ieee80211_local *local)
392 {
393         struct ieee80211_sub_if_data *sdata;
394
395         lockdep_assert_held(&local->mtx);
396
397         rcu_read_lock();
398         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
399                 if (sdata->radar_required) {
400                         rcu_read_unlock();
401                         return true;
402                 }
403         }
404         rcu_read_unlock();
405
406         return false;
407 }
408
409 static bool
410 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
411                                  struct ieee80211_chanctx *ctx)
412 {
413         struct ieee80211_chanctx_conf *conf = &ctx->conf;
414         struct ieee80211_sub_if_data *sdata;
415         bool required = false;
416
417         lockdep_assert_held(&local->chanctx_mtx);
418         lockdep_assert_held(&local->mtx);
419
420         rcu_read_lock();
421         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
422                 if (!ieee80211_sdata_running(sdata))
423                         continue;
424                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
425                         continue;
426                 if (!sdata->radar_required)
427                         continue;
428
429                 required = true;
430                 break;
431         }
432         rcu_read_unlock();
433
434         return required;
435 }
436
437 static struct ieee80211_chanctx *
438 ieee80211_alloc_chanctx(struct ieee80211_local *local,
439                         const struct cfg80211_chan_def *chandef,
440                         enum ieee80211_chanctx_mode mode)
441 {
442         struct ieee80211_chanctx *ctx;
443
444         lockdep_assert_held(&local->chanctx_mtx);
445
446         ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
447         if (!ctx)
448                 return NULL;
449
450         INIT_LIST_HEAD(&ctx->assigned_vifs);
451         INIT_LIST_HEAD(&ctx->reserved_vifs);
452         ctx->conf.def = *chandef;
453         ctx->conf.rx_chains_static = 1;
454         ctx->conf.rx_chains_dynamic = 1;
455         ctx->mode = mode;
456         ctx->conf.radar_enabled = false;
457         ieee80211_recalc_chanctx_min_def(local, ctx);
458
459         return ctx;
460 }
461
462 static int ieee80211_add_chanctx(struct ieee80211_local *local,
463                                  struct ieee80211_chanctx *ctx)
464 {
465         u32 changed;
466         int err;
467
468         lockdep_assert_held(&local->mtx);
469         lockdep_assert_held(&local->chanctx_mtx);
470
471         if (!local->use_chanctx)
472                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
473
474         /* turn idle off *before* setting channel -- some drivers need that */
475         changed = ieee80211_idle_off(local);
476         if (changed)
477                 ieee80211_hw_config(local, changed);
478
479         if (!local->use_chanctx) {
480                 local->_oper_chandef = ctx->conf.def;
481                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
482         } else {
483                 err = drv_add_chanctx(local, ctx);
484                 if (err) {
485                         ieee80211_recalc_idle(local);
486                         return err;
487                 }
488         }
489
490         return 0;
491 }
492
493 static struct ieee80211_chanctx *
494 ieee80211_new_chanctx(struct ieee80211_local *local,
495                       const struct cfg80211_chan_def *chandef,
496                       enum ieee80211_chanctx_mode mode)
497 {
498         struct ieee80211_chanctx *ctx;
499         int err;
500
501         lockdep_assert_held(&local->mtx);
502         lockdep_assert_held(&local->chanctx_mtx);
503
504         ctx = ieee80211_alloc_chanctx(local, chandef, mode);
505         if (!ctx)
506                 return ERR_PTR(-ENOMEM);
507
508         err = ieee80211_add_chanctx(local, ctx);
509         if (err) {
510                 kfree(ctx);
511                 return ERR_PTR(err);
512         }
513
514         list_add_rcu(&ctx->list, &local->chanctx_list);
515         return ctx;
516 }
517
518 static void ieee80211_del_chanctx(struct ieee80211_local *local,
519                                   struct ieee80211_chanctx *ctx)
520 {
521         lockdep_assert_held(&local->chanctx_mtx);
522
523         if (!local->use_chanctx) {
524                 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
525                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
526                 chandef->center_freq1 = chandef->chan->center_freq;
527                 chandef->center_freq2 = 0;
528
529                 /* NOTE: Disabling radar is only valid here for
530                  * single channel context. To be sure, check it ...
531                  */
532                 WARN_ON(local->hw.conf.radar_enabled &&
533                         !list_empty(&local->chanctx_list));
534
535                 local->hw.conf.radar_enabled = false;
536
537                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
538         } else {
539                 drv_remove_chanctx(local, ctx);
540         }
541
542         ieee80211_recalc_idle(local);
543 }
544
545 static void ieee80211_free_chanctx(struct ieee80211_local *local,
546                                    struct ieee80211_chanctx *ctx)
547 {
548         lockdep_assert_held(&local->chanctx_mtx);
549
550         WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
551
552         list_del_rcu(&ctx->list);
553         ieee80211_del_chanctx(local, ctx);
554         kfree_rcu(ctx, rcu_head);
555 }
556
557 static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
558                                               struct ieee80211_chanctx *ctx)
559 {
560         struct ieee80211_chanctx_conf *conf = &ctx->conf;
561         struct ieee80211_sub_if_data *sdata;
562         const struct cfg80211_chan_def *compat = NULL;
563
564         lockdep_assert_held(&local->chanctx_mtx);
565
566         rcu_read_lock();
567         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
568
569                 if (!ieee80211_sdata_running(sdata))
570                         continue;
571                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
572                         continue;
573                 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
574                         continue;
575
576                 if (!compat)
577                         compat = &sdata->vif.bss_conf.chandef;
578
579                 compat = cfg80211_chandef_compatible(
580                                 &sdata->vif.bss_conf.chandef, compat);
581                 if (WARN_ON_ONCE(!compat))
582                         break;
583         }
584         rcu_read_unlock();
585
586         if (!compat)
587                 return;
588
589         ieee80211_change_chanctx(local, ctx, compat);
590 }
591
592 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
593                                            struct ieee80211_chanctx *chanctx)
594 {
595         bool radar_enabled;
596
597         lockdep_assert_held(&local->chanctx_mtx);
598         /* for ieee80211_is_radar_required */
599         lockdep_assert_held(&local->mtx);
600
601         radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
602
603         if (radar_enabled == chanctx->conf.radar_enabled)
604                 return;
605
606         chanctx->conf.radar_enabled = radar_enabled;
607
608         if (!local->use_chanctx) {
609                 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
610                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
611         }
612
613         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
614 }
615
616 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
617                                         struct ieee80211_chanctx *new_ctx)
618 {
619         struct ieee80211_local *local = sdata->local;
620         struct ieee80211_chanctx_conf *conf;
621         struct ieee80211_chanctx *curr_ctx = NULL;
622         int ret = 0;
623
624         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
625                                          lockdep_is_held(&local->chanctx_mtx));
626
627         if (conf) {
628                 curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
629
630                 drv_unassign_vif_chanctx(local, sdata, curr_ctx);
631                 conf = NULL;
632                 list_del(&sdata->assigned_chanctx_list);
633         }
634
635         if (new_ctx) {
636                 ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
637                 if (ret)
638                         goto out;
639
640                 conf = &new_ctx->conf;
641                 list_add(&sdata->assigned_chanctx_list,
642                          &new_ctx->assigned_vifs);
643         }
644
645 out:
646         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
647
648         sdata->vif.bss_conf.idle = !conf;
649
650         if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
651                 ieee80211_recalc_chanctx_chantype(local, curr_ctx);
652                 ieee80211_recalc_smps_chanctx(local, curr_ctx);
653                 ieee80211_recalc_radar_chanctx(local, curr_ctx);
654                 ieee80211_recalc_chanctx_min_def(local, curr_ctx);
655         }
656
657         if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
658                 ieee80211_recalc_txpower(sdata);
659                 ieee80211_recalc_chanctx_min_def(local, new_ctx);
660         }
661
662         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
663             sdata->vif.type != NL80211_IFTYPE_MONITOR)
664                 ieee80211_bss_info_change_notify(sdata,
665                                                  BSS_CHANGED_IDLE);
666
667         return ret;
668 }
669
670 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
671                                    struct ieee80211_chanctx *chanctx)
672 {
673         struct ieee80211_sub_if_data *sdata;
674         u8 rx_chains_static, rx_chains_dynamic;
675
676         lockdep_assert_held(&local->chanctx_mtx);
677
678         rx_chains_static = 1;
679         rx_chains_dynamic = 1;
680
681         rcu_read_lock();
682         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
683                 u8 needed_static, needed_dynamic;
684
685                 if (!ieee80211_sdata_running(sdata))
686                         continue;
687
688                 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
689                                                 &chanctx->conf)
690                         continue;
691
692                 switch (sdata->vif.type) {
693                 case NL80211_IFTYPE_P2P_DEVICE:
694                         continue;
695                 case NL80211_IFTYPE_STATION:
696                         if (!sdata->u.mgd.associated)
697                                 continue;
698                         break;
699                 case NL80211_IFTYPE_AP_VLAN:
700                         continue;
701                 case NL80211_IFTYPE_AP:
702                 case NL80211_IFTYPE_ADHOC:
703                 case NL80211_IFTYPE_WDS:
704                 case NL80211_IFTYPE_MESH_POINT:
705                 case NL80211_IFTYPE_OCB:
706                         break;
707                 default:
708                         WARN_ON_ONCE(1);
709                 }
710
711                 switch (sdata->smps_mode) {
712                 default:
713                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
714                                   sdata->smps_mode);
715                         /* fall through */
716                 case IEEE80211_SMPS_OFF:
717                         needed_static = sdata->needed_rx_chains;
718                         needed_dynamic = sdata->needed_rx_chains;
719                         break;
720                 case IEEE80211_SMPS_DYNAMIC:
721                         needed_static = 1;
722                         needed_dynamic = sdata->needed_rx_chains;
723                         break;
724                 case IEEE80211_SMPS_STATIC:
725                         needed_static = 1;
726                         needed_dynamic = 1;
727                         break;
728                 }
729
730                 rx_chains_static = max(rx_chains_static, needed_static);
731                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
732         }
733
734         /* Disable SMPS for the monitor interface */
735         sdata = rcu_dereference(local->monitor_sdata);
736         if (sdata &&
737             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
738                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
739
740         rcu_read_unlock();
741
742         if (!local->use_chanctx) {
743                 if (rx_chains_static > 1)
744                         local->smps_mode = IEEE80211_SMPS_OFF;
745                 else if (rx_chains_dynamic > 1)
746                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
747                 else
748                         local->smps_mode = IEEE80211_SMPS_STATIC;
749                 ieee80211_hw_config(local, 0);
750         }
751
752         if (rx_chains_static == chanctx->conf.rx_chains_static &&
753             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
754                 return;
755
756         chanctx->conf.rx_chains_static = rx_chains_static;
757         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
758         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
759 }
760
761 static void
762 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
763                                       bool clear)
764 {
765         struct ieee80211_local *local __maybe_unused = sdata->local;
766         struct ieee80211_sub_if_data *vlan;
767         struct ieee80211_chanctx_conf *conf;
768
769         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
770                 return;
771
772         lockdep_assert_held(&local->mtx);
773
774         /* Check that conf exists, even when clearing this function
775          * must be called with the AP's channel context still there
776          * as it would otherwise cause VLANs to have an invalid
777          * channel context pointer for a while, possibly pointing
778          * to a channel context that has already been freed.
779          */
780         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
781                                          lockdep_is_held(&local->chanctx_mtx));
782         WARN_ON(!conf);
783
784         if (clear)
785                 conf = NULL;
786
787         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
788                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
789 }
790
791 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
792                                          bool clear)
793 {
794         struct ieee80211_local *local = sdata->local;
795
796         mutex_lock(&local->chanctx_mtx);
797
798         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
799
800         mutex_unlock(&local->chanctx_mtx);
801 }
802
803 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
804 {
805         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
806
807         lockdep_assert_held(&sdata->local->chanctx_mtx);
808
809         if (WARN_ON(!ctx))
810                 return -EINVAL;
811
812         list_del(&sdata->reserved_chanctx_list);
813         sdata->reserved_chanctx = NULL;
814
815         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
816                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
817                         if (WARN_ON(!ctx->replace_ctx))
818                                 return -EINVAL;
819
820                         WARN_ON(ctx->replace_ctx->replace_state !=
821                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
822                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
823
824                         ctx->replace_ctx->replace_ctx = NULL;
825                         ctx->replace_ctx->replace_state =
826                                         IEEE80211_CHANCTX_REPLACE_NONE;
827
828                         list_del_rcu(&ctx->list);
829                         kfree_rcu(ctx, rcu_head);
830                 } else {
831                         ieee80211_free_chanctx(sdata->local, ctx);
832                 }
833         }
834
835         return 0;
836 }
837
838 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
839                                   const struct cfg80211_chan_def *chandef,
840                                   enum ieee80211_chanctx_mode mode,
841                                   bool radar_required)
842 {
843         struct ieee80211_local *local = sdata->local;
844         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
845
846         lockdep_assert_held(&local->chanctx_mtx);
847
848         curr_ctx = ieee80211_vif_get_chanctx(sdata);
849         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
850                 return -ENOTSUPP;
851
852         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
853         if (!new_ctx) {
854                 if (ieee80211_can_create_new_chanctx(local)) {
855                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
856                         if (IS_ERR(new_ctx))
857                                 return PTR_ERR(new_ctx);
858                 } else {
859                         if (!curr_ctx ||
860                             (curr_ctx->replace_state ==
861                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
862                             !list_empty(&curr_ctx->reserved_vifs)) {
863                                 /*
864                                  * Another vif already requested this context
865                                  * for a reservation. Find another one hoping
866                                  * all vifs assigned to it will also switch
867                                  * soon enough.
868                                  *
869                                  * TODO: This needs a little more work as some
870                                  * cases (more than 2 chanctx capable devices)
871                                  * may fail which could otherwise succeed
872                                  * provided some channel context juggling was
873                                  * performed.
874                                  *
875                                  * Consider ctx1..3, vif1..6, each ctx has 2
876                                  * vifs. vif1 and vif2 from ctx1 request new
877                                  * different chandefs starting 2 in-place
878                                  * reserations with ctx4 and ctx5 replacing
879                                  * ctx1 and ctx2 respectively. Next vif5 and
880                                  * vif6 from ctx3 reserve ctx4. If vif3 and
881                                  * vif4 remain on ctx2 as they are then this
882                                  * fails unless `replace_ctx` from ctx5 is
883                                  * replaced with ctx3.
884                                  */
885                                 list_for_each_entry(ctx, &local->chanctx_list,
886                                                     list) {
887                                         if (ctx->replace_state !=
888                                             IEEE80211_CHANCTX_REPLACE_NONE)
889                                                 continue;
890
891                                         if (!list_empty(&ctx->reserved_vifs))
892                                                 continue;
893
894                                         curr_ctx = ctx;
895                                         break;
896                                 }
897                         }
898
899                         /*
900                          * If that's true then all available contexts already
901                          * have reservations and cannot be used.
902                          */
903                         if (!curr_ctx ||
904                             (curr_ctx->replace_state ==
905                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
906                             !list_empty(&curr_ctx->reserved_vifs))
907                                 return -EBUSY;
908
909                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
910                         if (!new_ctx)
911                                 return -ENOMEM;
912
913                         new_ctx->replace_ctx = curr_ctx;
914                         new_ctx->replace_state =
915                                         IEEE80211_CHANCTX_REPLACES_OTHER;
916
917                         curr_ctx->replace_ctx = new_ctx;
918                         curr_ctx->replace_state =
919                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
920
921                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
922                 }
923         }
924
925         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
926         sdata->reserved_chanctx = new_ctx;
927         sdata->reserved_chandef = *chandef;
928         sdata->reserved_radar_required = radar_required;
929         sdata->reserved_ready = false;
930
931         return 0;
932 }
933
934 static void
935 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
936 {
937         switch (sdata->vif.type) {
938         case NL80211_IFTYPE_ADHOC:
939         case NL80211_IFTYPE_AP:
940         case NL80211_IFTYPE_MESH_POINT:
941         case NL80211_IFTYPE_OCB:
942                 ieee80211_queue_work(&sdata->local->hw,
943                                      &sdata->csa_finalize_work);
944                 break;
945         case NL80211_IFTYPE_STATION:
946                 ieee80211_queue_work(&sdata->local->hw,
947                                      &sdata->u.mgd.chswitch_work);
948                 break;
949         case NL80211_IFTYPE_UNSPECIFIED:
950         case NL80211_IFTYPE_AP_VLAN:
951         case NL80211_IFTYPE_WDS:
952         case NL80211_IFTYPE_MONITOR:
953         case NL80211_IFTYPE_P2P_CLIENT:
954         case NL80211_IFTYPE_P2P_GO:
955         case NL80211_IFTYPE_P2P_DEVICE:
956         case NUM_NL80211_IFTYPES:
957                 WARN_ON(1);
958                 break;
959         }
960 }
961
962 static void
963 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
964                              const struct cfg80211_chan_def *chandef)
965 {
966         struct ieee80211_sub_if_data *vlan;
967
968         sdata->vif.bss_conf.chandef = *chandef;
969
970         if (sdata->vif.type != NL80211_IFTYPE_AP)
971                 return;
972
973         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
974                 vlan->vif.bss_conf.chandef = *chandef;
975 }
976
977 static int
978 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
979 {
980         struct ieee80211_local *local = sdata->local;
981         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
982         struct ieee80211_chanctx *old_ctx, *new_ctx;
983         const struct cfg80211_chan_def *chandef;
984         u32 changed = 0;
985         int err;
986
987         lockdep_assert_held(&local->mtx);
988         lockdep_assert_held(&local->chanctx_mtx);
989
990         new_ctx = sdata->reserved_chanctx;
991         old_ctx = ieee80211_vif_get_chanctx(sdata);
992
993         if (WARN_ON(!sdata->reserved_ready))
994                 return -EBUSY;
995
996         if (WARN_ON(!new_ctx))
997                 return -EINVAL;
998
999         if (WARN_ON(!old_ctx))
1000                 return -EINVAL;
1001
1002         if (WARN_ON(new_ctx->replace_state ==
1003                     IEEE80211_CHANCTX_REPLACES_OTHER))
1004                 return -EINVAL;
1005
1006         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1007                                 &sdata->reserved_chandef);
1008         if (WARN_ON(!chandef))
1009                 return -EINVAL;
1010
1011         vif_chsw[0].vif = &sdata->vif;
1012         vif_chsw[0].old_ctx = &old_ctx->conf;
1013         vif_chsw[0].new_ctx = &new_ctx->conf;
1014
1015         list_del(&sdata->reserved_chanctx_list);
1016         sdata->reserved_chanctx = NULL;
1017
1018         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1019                                      CHANCTX_SWMODE_REASSIGN_VIF);
1020         if (err) {
1021                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1022                         ieee80211_free_chanctx(local, new_ctx);
1023
1024                 goto out;
1025         }
1026
1027         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1028         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1029
1030         if (sdata->vif.type == NL80211_IFTYPE_AP)
1031                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1032
1033         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1034                 ieee80211_free_chanctx(local, old_ctx);
1035
1036         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1037                 changed = BSS_CHANGED_BANDWIDTH;
1038
1039         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1040
1041         ieee80211_recalc_smps_chanctx(local, new_ctx);
1042         ieee80211_recalc_radar_chanctx(local, new_ctx);
1043         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1044
1045         if (changed)
1046                 ieee80211_bss_info_change_notify(sdata, changed);
1047
1048 out:
1049         ieee80211_vif_chanctx_reservation_complete(sdata);
1050         return err;
1051 }
1052
1053 static int
1054 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1055 {
1056         struct ieee80211_local *local = sdata->local;
1057         struct ieee80211_chanctx *old_ctx, *new_ctx;
1058         const struct cfg80211_chan_def *chandef;
1059         int err;
1060
1061         old_ctx = ieee80211_vif_get_chanctx(sdata);
1062         new_ctx = sdata->reserved_chanctx;
1063
1064         if (WARN_ON(!sdata->reserved_ready))
1065                 return -EINVAL;
1066
1067         if (WARN_ON(old_ctx))
1068                 return -EINVAL;
1069
1070         if (WARN_ON(!new_ctx))
1071                 return -EINVAL;
1072
1073         if (WARN_ON(new_ctx->replace_state ==
1074                     IEEE80211_CHANCTX_REPLACES_OTHER))
1075                 return -EINVAL;
1076
1077         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1078                                 &sdata->reserved_chandef);
1079         if (WARN_ON(!chandef))
1080                 return -EINVAL;
1081
1082         list_del(&sdata->reserved_chanctx_list);
1083         sdata->reserved_chanctx = NULL;
1084
1085         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1086         if (err) {
1087                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1088                         ieee80211_free_chanctx(local, new_ctx);
1089
1090                 goto out;
1091         }
1092
1093 out:
1094         ieee80211_vif_chanctx_reservation_complete(sdata);
1095         return err;
1096 }
1097
1098 static bool
1099 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1100 {
1101         struct ieee80211_chanctx *old_ctx, *new_ctx;
1102
1103         lockdep_assert_held(&sdata->local->chanctx_mtx);
1104
1105         new_ctx = sdata->reserved_chanctx;
1106         old_ctx = ieee80211_vif_get_chanctx(sdata);
1107
1108         if (!old_ctx)
1109                 return false;
1110
1111         if (WARN_ON(!new_ctx))
1112                 return false;
1113
1114         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1115                 return false;
1116
1117         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1118                 return false;
1119
1120         return true;
1121 }
1122
1123 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1124                                         struct ieee80211_chanctx *new_ctx)
1125 {
1126         const struct cfg80211_chan_def *chandef;
1127
1128         lockdep_assert_held(&local->mtx);
1129         lockdep_assert_held(&local->chanctx_mtx);
1130
1131         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1132         if (WARN_ON(!chandef))
1133                 return -EINVAL;
1134
1135         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1136         local->_oper_chandef = *chandef;
1137         ieee80211_hw_config(local, 0);
1138
1139         return 0;
1140 }
1141
1142 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1143                                       int n_vifs)
1144 {
1145         struct ieee80211_vif_chanctx_switch *vif_chsw;
1146         struct ieee80211_sub_if_data *sdata;
1147         struct ieee80211_chanctx *ctx, *old_ctx;
1148         int i, err;
1149
1150         lockdep_assert_held(&local->mtx);
1151         lockdep_assert_held(&local->chanctx_mtx);
1152
1153         vif_chsw = kzalloc(sizeof(vif_chsw[0]) * n_vifs, GFP_KERNEL);
1154         if (!vif_chsw)
1155                 return -ENOMEM;
1156
1157         i = 0;
1158         list_for_each_entry(ctx, &local->chanctx_list, list) {
1159                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1160                         continue;
1161
1162                 if (WARN_ON(!ctx->replace_ctx)) {
1163                         err = -EINVAL;
1164                         goto out;
1165                 }
1166
1167                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1168                                     reserved_chanctx_list) {
1169                         if (!ieee80211_vif_has_in_place_reservation(
1170                                         sdata))
1171                                 continue;
1172
1173                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1174                         vif_chsw[i].vif = &sdata->vif;
1175                         vif_chsw[i].old_ctx = &old_ctx->conf;
1176                         vif_chsw[i].new_ctx = &ctx->conf;
1177
1178                         i++;
1179                 }
1180         }
1181
1182         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1183                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1184
1185 out:
1186         kfree(vif_chsw);
1187         return err;
1188 }
1189
1190 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1191 {
1192         struct ieee80211_chanctx *ctx;
1193         int err;
1194
1195         lockdep_assert_held(&local->mtx);
1196         lockdep_assert_held(&local->chanctx_mtx);
1197
1198         list_for_each_entry(ctx, &local->chanctx_list, list) {
1199                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1200                         continue;
1201
1202                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1203                         continue;
1204
1205                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1206                 err = ieee80211_add_chanctx(local, ctx);
1207                 if (err)
1208                         goto err;
1209         }
1210
1211         return 0;
1212
1213 err:
1214         WARN_ON(ieee80211_add_chanctx(local, ctx));
1215         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1216                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1217                         continue;
1218
1219                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1220                         continue;
1221
1222                 ieee80211_del_chanctx(local, ctx);
1223                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1224         }
1225
1226         return err;
1227 }
1228
1229 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1230 {
1231         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1232         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1233         struct ieee80211_chanctx *new_ctx = NULL;
1234         int i, err, n_assigned, n_reserved, n_ready;
1235         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1236
1237         lockdep_assert_held(&local->mtx);
1238         lockdep_assert_held(&local->chanctx_mtx);
1239
1240         /*
1241          * If there are 2 independent pairs of channel contexts performing
1242          * cross-switch of their vifs this code will still wait until both are
1243          * ready even though it could be possible to switch one before the
1244          * other is ready.
1245          *
1246          * For practical reasons and code simplicity just do a single huge
1247          * switch.
1248          */
1249
1250         /*
1251          * Verify if the reservation is still feasible.
1252          *  - if it's not then disconnect
1253          *  - if it is but not all vifs necessary are ready then defer
1254          */
1255
1256         list_for_each_entry(ctx, &local->chanctx_list, list) {
1257                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1258                         continue;
1259
1260                 if (WARN_ON(!ctx->replace_ctx)) {
1261                         err = -EINVAL;
1262                         goto err;
1263                 }
1264
1265                 if (!local->use_chanctx)
1266                         new_ctx = ctx;
1267
1268                 n_ctx++;
1269
1270                 n_assigned = 0;
1271                 n_reserved = 0;
1272                 n_ready = 0;
1273
1274                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1275                                     assigned_chanctx_list) {
1276                         n_assigned++;
1277                         if (sdata->reserved_chanctx) {
1278                                 n_reserved++;
1279                                 if (sdata->reserved_ready)
1280                                         n_ready++;
1281                         }
1282                 }
1283
1284                 if (n_assigned != n_reserved) {
1285                         if (n_ready == n_reserved) {
1286                                 wiphy_info(local->hw.wiphy,
1287                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1288                                 err = -EBUSY;
1289                                 goto err;
1290                         }
1291
1292                         return -EAGAIN;
1293                 }
1294
1295                 ctx->conf.radar_enabled = false;
1296                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1297                                     reserved_chanctx_list) {
1298                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1299                             !sdata->reserved_ready)
1300                                 return -EAGAIN;
1301
1302                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1303                         if (old_ctx) {
1304                                 if (old_ctx->replace_state ==
1305                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1306                                         n_vifs_switch++;
1307                                 else
1308                                         n_vifs_assign++;
1309                         } else {
1310                                 n_vifs_ctxless++;
1311                         }
1312
1313                         if (sdata->reserved_radar_required)
1314                                 ctx->conf.radar_enabled = true;
1315                 }
1316         }
1317
1318         if (WARN_ON(n_ctx == 0) ||
1319             WARN_ON(n_vifs_switch == 0 &&
1320                     n_vifs_assign == 0 &&
1321                     n_vifs_ctxless == 0) ||
1322             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1323             WARN_ON(!new_ctx && !local->use_chanctx)) {
1324                 err = -EINVAL;
1325                 goto err;
1326         }
1327
1328         /*
1329          * All necessary vifs are ready. Perform the switch now depending on
1330          * reservations and driver capabilities.
1331          */
1332
1333         if (local->use_chanctx) {
1334                 if (n_vifs_switch > 0) {
1335                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1336                         if (err)
1337                                 goto err;
1338                 }
1339
1340                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1341                         err = ieee80211_chsw_switch_ctxs(local);
1342                         if (err)
1343                                 goto err;
1344                 }
1345         } else {
1346                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1347                 if (err)
1348                         goto err;
1349         }
1350
1351         /*
1352          * Update all structures, values and pointers to point to new channel
1353          * context(s).
1354          */
1355
1356         i = 0;
1357         list_for_each_entry(ctx, &local->chanctx_list, list) {
1358                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1359                         continue;
1360
1361                 if (WARN_ON(!ctx->replace_ctx)) {
1362                         err = -EINVAL;
1363                         goto err;
1364                 }
1365
1366                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1367                                     reserved_chanctx_list) {
1368                         u32 changed = 0;
1369
1370                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1371                                 continue;
1372
1373                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1374
1375                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1376                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1377                                                                       false);
1378
1379                         sdata->radar_required = sdata->reserved_radar_required;
1380
1381                         if (sdata->vif.bss_conf.chandef.width !=
1382                             sdata->reserved_chandef.width)
1383                                 changed = BSS_CHANGED_BANDWIDTH;
1384
1385                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1386                         if (changed)
1387                                 ieee80211_bss_info_change_notify(sdata,
1388                                                                  changed);
1389
1390                         ieee80211_recalc_txpower(sdata);
1391                 }
1392
1393                 ieee80211_recalc_chanctx_chantype(local, ctx);
1394                 ieee80211_recalc_smps_chanctx(local, ctx);
1395                 ieee80211_recalc_radar_chanctx(local, ctx);
1396                 ieee80211_recalc_chanctx_min_def(local, ctx);
1397
1398                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1399                                          reserved_chanctx_list) {
1400                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1401                                 continue;
1402
1403                         list_del(&sdata->reserved_chanctx_list);
1404                         list_move(&sdata->assigned_chanctx_list,
1405                                   &ctx->assigned_vifs);
1406                         sdata->reserved_chanctx = NULL;
1407
1408                         ieee80211_vif_chanctx_reservation_complete(sdata);
1409                 }
1410
1411                 /*
1412                  * This context might have been a dependency for an already
1413                  * ready re-assign reservation interface that was deferred. Do
1414                  * not propagate error to the caller though. The in-place
1415                  * reservation for originally requested interface has already
1416                  * succeeded at this point.
1417                  */
1418                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1419                                          reserved_chanctx_list) {
1420                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1421                                         sdata)))
1422                                 continue;
1423
1424                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1425                                 continue;
1426
1427                         if (!sdata->reserved_ready)
1428                                 continue;
1429
1430                         if (ieee80211_vif_get_chanctx(sdata))
1431                                 err = ieee80211_vif_use_reserved_reassign(
1432                                                 sdata);
1433                         else
1434                                 err = ieee80211_vif_use_reserved_assign(sdata);
1435
1436                         if (err) {
1437                                 sdata_info(sdata,
1438                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1439                                            err);
1440                                 ieee80211_vif_unreserve_chanctx(sdata);
1441                                 cfg80211_stop_iface(local->hw.wiphy,
1442                                                     &sdata->wdev,
1443                                                     GFP_KERNEL);
1444                         }
1445                 }
1446         }
1447
1448         /*
1449          * Finally free old contexts
1450          */
1451
1452         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1453                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1454                         continue;
1455
1456                 ctx->replace_ctx->replace_ctx = NULL;
1457                 ctx->replace_ctx->replace_state =
1458                                 IEEE80211_CHANCTX_REPLACE_NONE;
1459
1460                 list_del_rcu(&ctx->list);
1461                 kfree_rcu(ctx, rcu_head);
1462         }
1463
1464         return 0;
1465
1466 err:
1467         list_for_each_entry(ctx, &local->chanctx_list, list) {
1468                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1469                         continue;
1470
1471                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1472                                          reserved_chanctx_list) {
1473                         ieee80211_vif_unreserve_chanctx(sdata);
1474                         ieee80211_vif_chanctx_reservation_complete(sdata);
1475                 }
1476         }
1477
1478         return err;
1479 }
1480
1481 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1482 {
1483         struct ieee80211_local *local = sdata->local;
1484         struct ieee80211_chanctx_conf *conf;
1485         struct ieee80211_chanctx *ctx;
1486         bool use_reserved_switch = false;
1487
1488         lockdep_assert_held(&local->chanctx_mtx);
1489
1490         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1491                                          lockdep_is_held(&local->chanctx_mtx));
1492         if (!conf)
1493                 return;
1494
1495         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1496
1497         if (sdata->reserved_chanctx) {
1498                 if (sdata->reserved_chanctx->replace_state ==
1499                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1500                     ieee80211_chanctx_num_reserved(local,
1501                                                    sdata->reserved_chanctx) > 1)
1502                         use_reserved_switch = true;
1503
1504                 ieee80211_vif_unreserve_chanctx(sdata);
1505         }
1506
1507         ieee80211_assign_vif_chanctx(sdata, NULL);
1508         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1509                 ieee80211_free_chanctx(local, ctx);
1510
1511         /* Unreserving may ready an in-place reservation. */
1512         if (use_reserved_switch)
1513                 ieee80211_vif_use_reserved_switch(local);
1514 }
1515
1516 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1517                               const struct cfg80211_chan_def *chandef,
1518                               enum ieee80211_chanctx_mode mode)
1519 {
1520         struct ieee80211_local *local = sdata->local;
1521         struct ieee80211_chanctx *ctx;
1522         u8 radar_detect_width = 0;
1523         int ret;
1524
1525         lockdep_assert_held(&local->mtx);
1526
1527         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1528
1529         mutex_lock(&local->chanctx_mtx);
1530
1531         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1532                                             chandef,
1533                                             sdata->wdev.iftype);
1534         if (ret < 0)
1535                 goto out;
1536         if (ret > 0)
1537                 radar_detect_width = BIT(chandef->width);
1538
1539         sdata->radar_required = ret;
1540
1541         ret = ieee80211_check_combinations(sdata, chandef, mode,
1542                                            radar_detect_width);
1543         if (ret < 0)
1544                 goto out;
1545
1546         __ieee80211_vif_release_channel(sdata);
1547
1548         ctx = ieee80211_find_chanctx(local, chandef, mode);
1549         if (!ctx)
1550                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1551         if (IS_ERR(ctx)) {
1552                 ret = PTR_ERR(ctx);
1553                 goto out;
1554         }
1555
1556         ieee80211_vif_update_chandef(sdata, chandef);
1557
1558         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1559         if (ret) {
1560                 /* if assign fails refcount stays the same */
1561                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1562                         ieee80211_free_chanctx(local, ctx);
1563                 goto out;
1564         }
1565
1566         ieee80211_recalc_smps_chanctx(local, ctx);
1567         ieee80211_recalc_radar_chanctx(local, ctx);
1568  out:
1569         mutex_unlock(&local->chanctx_mtx);
1570         return ret;
1571 }
1572
1573 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1574 {
1575         struct ieee80211_local *local = sdata->local;
1576         struct ieee80211_chanctx *new_ctx;
1577         struct ieee80211_chanctx *old_ctx;
1578         int err;
1579
1580         lockdep_assert_held(&local->mtx);
1581         lockdep_assert_held(&local->chanctx_mtx);
1582
1583         new_ctx = sdata->reserved_chanctx;
1584         old_ctx = ieee80211_vif_get_chanctx(sdata);
1585
1586         if (WARN_ON(!new_ctx))
1587                 return -EINVAL;
1588
1589         if (WARN_ON(new_ctx->replace_state ==
1590                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1591                 return -EINVAL;
1592
1593         if (WARN_ON(sdata->reserved_ready))
1594                 return -EINVAL;
1595
1596         sdata->reserved_ready = true;
1597
1598         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1599                 if (old_ctx)
1600                         err = ieee80211_vif_use_reserved_reassign(sdata);
1601                 else
1602                         err = ieee80211_vif_use_reserved_assign(sdata);
1603
1604                 if (err)
1605                         return err;
1606         }
1607
1608         /*
1609          * In-place reservation may need to be finalized now either if:
1610          *  a) sdata is taking part in the swapping itself and is the last one
1611          *  b) sdata has switched with a re-assign reservation to an existing
1612          *     context readying in-place switching of old_ctx
1613          *
1614          * In case of (b) do not propagate the error up because the requested
1615          * sdata already switched successfully. Just spill an extra warning.
1616          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1617          * interfaces upon failure.
1618          */
1619         if ((old_ctx &&
1620              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1621             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1622                 err = ieee80211_vif_use_reserved_switch(local);
1623                 if (err && err != -EAGAIN) {
1624                         if (new_ctx->replace_state ==
1625                             IEEE80211_CHANCTX_REPLACES_OTHER)
1626                                 return err;
1627
1628                         wiphy_info(local->hw.wiphy,
1629                                    "depending in-place reservation failed (err=%d)\n",
1630                                    err);
1631                 }
1632         }
1633
1634         return 0;
1635 }
1636
1637 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1638                                    const struct cfg80211_chan_def *chandef,
1639                                    u32 *changed)
1640 {
1641         struct ieee80211_local *local = sdata->local;
1642         struct ieee80211_chanctx_conf *conf;
1643         struct ieee80211_chanctx *ctx;
1644         const struct cfg80211_chan_def *compat;
1645         int ret;
1646
1647         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1648                                      IEEE80211_CHAN_DISABLED))
1649                 return -EINVAL;
1650
1651         mutex_lock(&local->chanctx_mtx);
1652         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1653                 ret = 0;
1654                 goto out;
1655         }
1656
1657         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1658             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1659                 ret = -EINVAL;
1660                 goto out;
1661         }
1662
1663         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1664                                          lockdep_is_held(&local->chanctx_mtx));
1665         if (!conf) {
1666                 ret = -EINVAL;
1667                 goto out;
1668         }
1669
1670         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1671
1672         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1673         if (!compat) {
1674                 ret = -EINVAL;
1675                 goto out;
1676         }
1677
1678         switch (ctx->replace_state) {
1679         case IEEE80211_CHANCTX_REPLACE_NONE:
1680                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1681                         ret = -EBUSY;
1682                         goto out;
1683                 }
1684                 break;
1685         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1686                 /* TODO: Perhaps the bandwidth change could be treated as a
1687                  * reservation itself? */
1688                 ret = -EBUSY;
1689                 goto out;
1690         case IEEE80211_CHANCTX_REPLACES_OTHER:
1691                 /* channel context that is going to replace another channel
1692                  * context doesn't really exist and shouldn't be assigned
1693                  * anywhere yet */
1694                 WARN_ON(1);
1695                 break;
1696         }
1697
1698         ieee80211_vif_update_chandef(sdata, chandef);
1699
1700         ieee80211_recalc_chanctx_chantype(local, ctx);
1701
1702         *changed |= BSS_CHANGED_BANDWIDTH;
1703         ret = 0;
1704  out:
1705         mutex_unlock(&local->chanctx_mtx);
1706         return ret;
1707 }
1708
1709 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1710 {
1711         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1712
1713         lockdep_assert_held(&sdata->local->mtx);
1714
1715         mutex_lock(&sdata->local->chanctx_mtx);
1716         __ieee80211_vif_release_channel(sdata);
1717         mutex_unlock(&sdata->local->chanctx_mtx);
1718 }
1719
1720 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1721 {
1722         struct ieee80211_local *local = sdata->local;
1723         struct ieee80211_sub_if_data *ap;
1724         struct ieee80211_chanctx_conf *conf;
1725
1726         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1727                 return;
1728
1729         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1730
1731         mutex_lock(&local->chanctx_mtx);
1732
1733         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1734                                          lockdep_is_held(&local->chanctx_mtx));
1735         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1736         mutex_unlock(&local->chanctx_mtx);
1737 }
1738
1739 void ieee80211_iter_chan_contexts_atomic(
1740         struct ieee80211_hw *hw,
1741         void (*iter)(struct ieee80211_hw *hw,
1742                      struct ieee80211_chanctx_conf *chanctx_conf,
1743                      void *data),
1744         void *iter_data)
1745 {
1746         struct ieee80211_local *local = hw_to_local(hw);
1747         struct ieee80211_chanctx *ctx;
1748
1749         rcu_read_lock();
1750         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1751                 if (ctx->driver_present)
1752                         iter(hw, &ctx->conf, iter_data);
1753         rcu_read_unlock();
1754 }
1755 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);