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