net/mac80211/chan.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * mac80211 - channel management
   4  */
   5
   6 #include <linux/nl80211.h>
   7 #include <linux/export.h>
   8 #include <linux/rtnetlink.h>
   9 #include <net/cfg80211.h>
  10 #include "ieee80211_i.h"
  11 #include "driver-ops.h"
  12
  13 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
  14                                           struct ieee80211_chanctx *ctx)
  15 {
  16         struct ieee80211_sub_if_data *sdata;
  17         int num = 0;
  18
  19         lockdep_assert_held(&local->chanctx_mtx);
  20
  21         list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
  22                 num++;
  23
  24         return num;
  25 }
  26
  27 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
  28                                           struct ieee80211_chanctx *ctx)
  29 {
  30         struct ieee80211_sub_if_data *sdata;
  31         int num = 0;
  32
  33         lockdep_assert_held(&local->chanctx_mtx);
  34
  35         list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
  36                 num++;
  37
  38         return num;
  39 }
  40
  41 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
  42                                struct ieee80211_chanctx *ctx)
  43 {
  44         return ieee80211_chanctx_num_assigned(local, ctx) +
  45                ieee80211_chanctx_num_reserved(local, ctx);
  46 }
  47
  48 static int ieee80211_num_chanctx(struct ieee80211_local *local)
  49 {
  50         struct ieee80211_chanctx *ctx;
  51         int num = 0;
  52
  53         lockdep_assert_held(&local->chanctx_mtx);
  54
  55         list_for_each_entry(ctx, &local->chanctx_list, list)
  56                 num++;
  57
  58         return num;
  59 }
  60
  61 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
  62 {
  63         lockdep_assert_held(&local->chanctx_mtx);
  64         return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
  65 }
  66
  67 static struct ieee80211_chanctx *
  68 ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
  69 {
  70         struct ieee80211_local *local __maybe_unused = sdata->local;
  71         struct ieee80211_chanctx_conf *conf;
  72
  73         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
  74                                          lockdep_is_held(&local->chanctx_mtx));
  75         if (!conf)
  76                 return NULL;
  77
  78         return container_of(conf, struct ieee80211_chanctx, conf);
  79 }
  80
  81 static const struct cfg80211_chan_def *
  82 ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
  83                                    struct ieee80211_chanctx *ctx,
  84                                    const struct cfg80211_chan_def *compat)
  85 {
  86         struct ieee80211_sub_if_data *sdata;
  87
  88         lockdep_assert_held(&local->chanctx_mtx);
  89
  90         list_for_each_entry(sdata, &ctx->reserved_vifs,
  91                             reserved_chanctx_list) {
  92                 if (!compat)
  93                         compat = &sdata->reserved_chandef;
  94
  95                 compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
  96                                                      compat);
  97                 if (!compat)
  98                         break;
  99         }
 100
 101         return compat;
 102 }
 103
 104 static const struct cfg80211_chan_def *
 105 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
 106                                        struct ieee80211_chanctx *ctx,
 107                                        const struct cfg80211_chan_def *compat)
 108 {
 109         struct ieee80211_sub_if_data *sdata;
 110
 111         lockdep_assert_held(&local->chanctx_mtx);
 112
 113         list_for_each_entry(sdata, &ctx->assigned_vifs,
 114                             assigned_chanctx_list) {
 115                 if (sdata->reserved_chanctx != NULL)
 116                         continue;
 117
 118                 if (!compat)
 119                         compat = &sdata->vif.bss_conf.chandef;
 120
 121                 compat = cfg80211_chandef_compatible(
 122                                 &sdata->vif.bss_conf.chandef, compat);
 123                 if (!compat)
 124                         break;
 125         }
 126
 127         return compat;
 128 }
 129
 130 static const struct cfg80211_chan_def *
 131 ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
 132                                    struct ieee80211_chanctx *ctx,
 133                                    const struct cfg80211_chan_def *compat)
 134 {
 135         lockdep_assert_held(&local->chanctx_mtx);
 136
 137         compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
 138         if (!compat)
 139                 return NULL;
 140
 141         compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
 142         if (!compat)
 143                 return NULL;
 144
 145         return compat;
 146 }
 147
 148 static bool
 149 ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
 150                                       struct ieee80211_chanctx *ctx,
 151                                       const struct cfg80211_chan_def *def)
 152 {
 153         lockdep_assert_held(&local->chanctx_mtx);
 154
 155         if (ieee80211_chanctx_combined_chandef(local, ctx, def))
 156                 return true;
 157
 158         if (!list_empty(&ctx->reserved_vifs) &&
 159             ieee80211_chanctx_reserved_chandef(local, ctx, def))
 160                 return true;
 161
 162         return false;
 163 }
 164
 165 static struct ieee80211_chanctx *
 166 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
 167                                    const struct cfg80211_chan_def *chandef,
 168                                    enum ieee80211_chanctx_mode mode)
 169 {
 170         struct ieee80211_chanctx *ctx;
 171
 172         lockdep_assert_held(&local->chanctx_mtx);
 173
 174         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 175                 return NULL;
 176
 177         list_for_each_entry(ctx, &local->chanctx_list, list) {
 178                 if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
 179                         continue;
 180
 181                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 182                         continue;
 183
 184                 if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
 185                                                            chandef))
 186                         continue;
 187
 188                 return ctx;
 189         }
 190
 191         return NULL;
 192 }
 193
 194 enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
 195 {
 196         switch (sta->bandwidth) {
 197         case IEEE80211_STA_RX_BW_20:
 198                 if (sta->ht_cap.ht_supported)
 199                         return NL80211_CHAN_WIDTH_20;
 200                 else
 201                         return NL80211_CHAN_WIDTH_20_NOHT;
 202         case IEEE80211_STA_RX_BW_40:
 203                 return NL80211_CHAN_WIDTH_40;
 204         case IEEE80211_STA_RX_BW_80:
 205                 return NL80211_CHAN_WIDTH_80;
 206         case IEEE80211_STA_RX_BW_160:
 207                 /*
 208                  * This applied for both 160 and 80+80. since we use
 209                  * the returned value to consider degradation of
 210                  * ctx->conf.min_def, we have to make sure to take
 211                  * the bigger one (NL80211_CHAN_WIDTH_160).
 212                  * Otherwise we might try degrading even when not
 213                  * needed, as the max required sta_bw returned (80+80)
 214                  * might be smaller than the configured bw (160).
 215                  */
 216                 return NL80211_CHAN_WIDTH_160;
 217         default:
 218                 WARN_ON(1);
 219                 return NL80211_CHAN_WIDTH_20;
 220         }
 221 }
 222
 223 static enum nl80211_chan_width
 224 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
 225 {
 226         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 227         struct sta_info *sta;
 228
 229         rcu_read_lock();
 230         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
 231                 if (sdata != sta->sdata &&
 232                     !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
 233                         continue;
 234
 235                 max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
 236         }
 237         rcu_read_unlock();
 238
 239         return max_bw;
 240 }
 241
 242 static enum nl80211_chan_width
 243 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
 244                                       struct ieee80211_chanctx_conf *conf)
 245 {
 246         struct ieee80211_sub_if_data *sdata;
 247         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 248
 249         rcu_read_lock();
 250         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 251                 struct ieee80211_vif *vif = &sdata->vif;
 252                 enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
 253
 254                 if (!ieee80211_sdata_running(sdata))
 255                         continue;
 256
 257                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 258                         continue;
 259
 260                 switch (vif->type) {
 261                 case NL80211_IFTYPE_AP:
 262                 case NL80211_IFTYPE_AP_VLAN:
 263                         width = ieee80211_get_max_required_bw(sdata);
 264                         break;
 265                 case NL80211_IFTYPE_STATION:
 266                         /*
 267                          * The ap's sta->bandwidth is not set yet at this
 268                          * point, so take the width from the chandef, but
 269                          * account also for TDLS peers
 270                          */
 271                         width = max(vif->bss_conf.chandef.width,
 272                                     ieee80211_get_max_required_bw(sdata));
 273                         break;
 274                 case NL80211_IFTYPE_P2P_DEVICE:
 275                 case NL80211_IFTYPE_NAN:
 276                         continue;
 277                 case NL80211_IFTYPE_ADHOC:
 278                 case NL80211_IFTYPE_WDS:
 279                 case NL80211_IFTYPE_MESH_POINT:
 280                 case NL80211_IFTYPE_OCB:
 281                         width = vif->bss_conf.chandef.width;
 282                         break;
 283                 case NL80211_IFTYPE_UNSPECIFIED:
 284                 case NUM_NL80211_IFTYPES:
 285                 case NL80211_IFTYPE_MONITOR:
 286                 case NL80211_IFTYPE_P2P_CLIENT:
 287                 case NL80211_IFTYPE_P2P_GO:
 288                         WARN_ON_ONCE(1);
 289                 }
 290                 max_bw = max(max_bw, width);
 291         }
 292
 293         /* use the configured bandwidth in case of monitor interface */
 294         sdata = rcu_dereference(local->monitor_sdata);
 295         if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
 296                 max_bw = max(max_bw, conf->def.width);
 297
 298         rcu_read_unlock();
 299
 300         return max_bw;
 301 }
 302
 303 /*
 304  * recalc the min required chan width of the channel context, which is
 305  * the max of min required widths of all the interfaces bound to this
 306  * channel context.
 307  */
 308 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
 309                                       struct ieee80211_chanctx *ctx)
 310 {
 311         enum nl80211_chan_width max_bw;
 312         struct cfg80211_chan_def min_def;
 313
 314         lockdep_assert_held(&local->chanctx_mtx);
 315
 316         /* don't optimize 5MHz, 10MHz, and radar_enabled confs */
 317         if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
 318             ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
 319             ctx->conf.radar_enabled) {
 320                 ctx->conf.min_def = ctx->conf.def;
 321                 return;
 322         }
 323
 324         max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
 325
 326         /* downgrade chandef up to max_bw */
 327         min_def = ctx->conf.def;
 328         while (min_def.width > max_bw)
 329                 ieee80211_chandef_downgrade(&min_def);
 330
 331         if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
 332                 return;
 333
 334         ctx->conf.min_def = min_def;
 335         if (!ctx->driver_present)
 336                 return;
 337
 338         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
 339 }
 340
 341 static void ieee80211_change_chanctx(struct ieee80211_local *local,
 342                                      struct ieee80211_chanctx *ctx,
 343                                      const struct cfg80211_chan_def *chandef)
 344 {
 345         if (cfg80211_chandef_identical(&ctx->conf.def, chandef)) {
 346                 ieee80211_recalc_chanctx_min_def(local, ctx);
 347                 return;
 348         }
 349
 350         WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
 351
 352         ctx->conf.def = *chandef;
 353         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
 354         ieee80211_recalc_chanctx_min_def(local, ctx);
 355
 356         if (!local->use_chanctx) {
 357                 local->_oper_chandef = *chandef;
 358                 ieee80211_hw_config(local, 0);
 359         }
 360 }
 361
 362 static struct ieee80211_chanctx *
 363 ieee80211_find_chanctx(struct ieee80211_local *local,
 364                        const struct cfg80211_chan_def *chandef,
 365                        enum ieee80211_chanctx_mode mode)
 366 {
 367         struct ieee80211_chanctx *ctx;
 368
 369         lockdep_assert_held(&local->chanctx_mtx);
 370
 371         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 372                 return NULL;
 373
 374         list_for_each_entry(ctx, &local->chanctx_list, list) {
 375                 const struct cfg80211_chan_def *compat;
 376
 377                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
 378                         continue;
 379
 380                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 381                         continue;
 382
 383                 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
 384                 if (!compat)
 385                         continue;
 386
 387                 compat = ieee80211_chanctx_reserved_chandef(local, ctx,
 388                                                             compat);
 389                 if (!compat)
 390                         continue;
 391
 392                 ieee80211_change_chanctx(local, ctx, compat);
 393
 394                 return ctx;
 395         }
 396
 397         return NULL;
 398 }
 399
 400 bool ieee80211_is_radar_required(struct ieee80211_local *local)
 401 {
 402         struct ieee80211_sub_if_data *sdata;
 403
 404         lockdep_assert_held(&local->mtx);
 405
 406         rcu_read_lock();
 407         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 408                 if (sdata->radar_required) {
 409                         rcu_read_unlock();
 410                         return true;
 411                 }
 412         }
 413         rcu_read_unlock();
 414
 415         return false;
 416 }
 417
 418 static bool
 419 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
 420                                  struct ieee80211_chanctx *ctx)
 421 {
 422         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 423         struct ieee80211_sub_if_data *sdata;
 424         bool required = false;
 425
 426         lockdep_assert_held(&local->chanctx_mtx);
 427         lockdep_assert_held(&local->mtx);
 428
 429         rcu_read_lock();
 430         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 431                 if (!ieee80211_sdata_running(sdata))
 432                         continue;
 433                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 434                         continue;
 435                 if (!sdata->radar_required)
 436                         continue;
 437
 438                 required = true;
 439                 break;
 440         }
 441         rcu_read_unlock();
 442
 443         return required;
 444 }
 445
 446 static struct ieee80211_chanctx *
 447 ieee80211_alloc_chanctx(struct ieee80211_local *local,
 448                         const struct cfg80211_chan_def *chandef,
 449                         enum ieee80211_chanctx_mode mode)
 450 {
 451         struct ieee80211_chanctx *ctx;
 452
 453         lockdep_assert_held(&local->chanctx_mtx);
 454
 455         ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
 456         if (!ctx)
 457                 return NULL;
 458
 459         INIT_LIST_HEAD(&ctx->assigned_vifs);
 460         INIT_LIST_HEAD(&ctx->reserved_vifs);
 461         ctx->conf.def = *chandef;
 462         ctx->conf.rx_chains_static = 1;
 463         ctx->conf.rx_chains_dynamic = 1;
 464         ctx->mode = mode;
 465         ctx->conf.radar_enabled = false;
 466         ieee80211_recalc_chanctx_min_def(local, ctx);
 467
 468         return ctx;
 469 }
 470
 471 static int ieee80211_add_chanctx(struct ieee80211_local *local,
 472                                  struct ieee80211_chanctx *ctx)
 473 {
 474         u32 changed;
 475         int err;
 476
 477         lockdep_assert_held(&local->mtx);
 478         lockdep_assert_held(&local->chanctx_mtx);
 479
 480         if (!local->use_chanctx)
 481                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 482
 483         /* turn idle off *before* setting channel -- some drivers need that */
 484         changed = ieee80211_idle_off(local);
 485         if (changed)
 486                 ieee80211_hw_config(local, changed);
 487
 488         if (!local->use_chanctx) {
 489                 local->_oper_chandef = ctx->conf.def;
 490                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 491         } else {
 492                 err = drv_add_chanctx(local, ctx);
 493                 if (err) {
 494                         ieee80211_recalc_idle(local);
 495                         return err;
 496                 }
 497         }
 498
 499         return 0;
 500 }
 501
 502 static struct ieee80211_chanctx *
 503 ieee80211_new_chanctx(struct ieee80211_local *local,
 504                       const struct cfg80211_chan_def *chandef,
 505                       enum ieee80211_chanctx_mode mode)
 506 {
 507         struct ieee80211_chanctx *ctx;
 508         int err;
 509
 510         lockdep_assert_held(&local->mtx);
 511         lockdep_assert_held(&local->chanctx_mtx);
 512
 513         ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 514         if (!ctx)
 515                 return ERR_PTR(-ENOMEM);
 516
 517         err = ieee80211_add_chanctx(local, ctx);
 518         if (err) {
 519                 kfree(ctx);
 520                 return ERR_PTR(err);
 521         }
 522
 523         list_add_rcu(&ctx->list, &local->chanctx_list);
 524         return ctx;
 525 }
 526
 527 static void ieee80211_del_chanctx(struct ieee80211_local *local,
 528                                   struct ieee80211_chanctx *ctx)
 529 {
 530         lockdep_assert_held(&local->chanctx_mtx);
 531
 532         if (!local->use_chanctx) {
 533                 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
 534                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 535                 chandef->center_freq1 = chandef->chan->center_freq;
 536                 chandef->center_freq2 = 0;
 537
 538                 /* NOTE: Disabling radar is only valid here for
 539                  * single channel context. To be sure, check it ...
 540                  */
 541                 WARN_ON(local->hw.conf.radar_enabled &&
 542                         !list_empty(&local->chanctx_list));
 543
 544                 local->hw.conf.radar_enabled = false;
 545
 546                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 547         } else {
 548                 drv_remove_chanctx(local, ctx);
 549         }
 550
 551         ieee80211_recalc_idle(local);
 552 }
 553
 554 static void ieee80211_free_chanctx(struct ieee80211_local *local,
 555                                    struct ieee80211_chanctx *ctx)
 556 {
 557         lockdep_assert_held(&local->chanctx_mtx);
 558
 559         WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
 560
 561         list_del_rcu(&ctx->list);
 562         ieee80211_del_chanctx(local, ctx);
 563         kfree_rcu(ctx, rcu_head);
 564 }
 565
 566 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 567                                        struct ieee80211_chanctx *ctx)
 568 {
 569         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 570         struct ieee80211_sub_if_data *sdata;
 571         const struct cfg80211_chan_def *compat = NULL;
 572         struct sta_info *sta;
 573
 574         lockdep_assert_held(&local->chanctx_mtx);
 575
 576         rcu_read_lock();
 577         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 578
 579                 if (!ieee80211_sdata_running(sdata))
 580                         continue;
 581                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 582                         continue;
 583                 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 584                         continue;
 585
 586                 if (!compat)
 587                         compat = &sdata->vif.bss_conf.chandef;
 588
 589                 compat = cfg80211_chandef_compatible(
 590                                 &sdata->vif.bss_conf.chandef, compat);
 591                 if (WARN_ON_ONCE(!compat))
 592                         break;
 593         }
 594
 595         /* TDLS peers can sometimes affect the chandef width */
 596         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 597                 if (!sta->uploaded ||
 598                     !test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW) ||
 599                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
 600                     !sta->tdls_chandef.chan)
 601                         continue;
 602
 603                 compat = cfg80211_chandef_compatible(&sta->tdls_chandef,
 604                                                      compat);
 605                 if (WARN_ON_ONCE(!compat))
 606                         break;
 607         }
 608         rcu_read_unlock();
 609
 610         if (!compat)
 611                 return;
 612
 613         ieee80211_change_chanctx(local, ctx, compat);
 614 }
 615
 616 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
 617                                            struct ieee80211_chanctx *chanctx)
 618 {
 619         bool radar_enabled;
 620
 621         lockdep_assert_held(&local->chanctx_mtx);
 622         /* for ieee80211_is_radar_required */
 623         lockdep_assert_held(&local->mtx);
 624
 625         radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
 626
 627         if (radar_enabled == chanctx->conf.radar_enabled)
 628                 return;
 629
 630         chanctx->conf.radar_enabled = radar_enabled;
 631
 632         if (!local->use_chanctx) {
 633                 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
 634                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 635         }
 636
 637         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
 638 }
 639
 640 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 641                                         struct ieee80211_chanctx *new_ctx)
 642 {
 643         struct ieee80211_local *local = sdata->local;
 644         struct ieee80211_chanctx_conf *conf;
 645         struct ieee80211_chanctx *curr_ctx = NULL;
 646         int ret = 0;
 647
 648         if (WARN_ON(sdata->vif.type == NL80211_IFTYPE_NAN))
 649                 return -ENOTSUPP;
 650
 651         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 652                                          lockdep_is_held(&local->chanctx_mtx));
 653
 654         if (conf) {
 655                 curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
 656
 657                 drv_unassign_vif_chanctx(local, sdata, curr_ctx);
 658                 conf = NULL;
 659                 list_del(&sdata->assigned_chanctx_list);
 660         }
 661
 662         if (new_ctx) {
 663                 ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
 664                 if (ret)
 665                         goto out;
 666
 667                 conf = &new_ctx->conf;
 668                 list_add(&sdata->assigned_chanctx_list,
 669                          &new_ctx->assigned_vifs);
 670         }
 671
 672 out:
 673         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
 674
 675         sdata->vif.bss_conf.idle = !conf;
 676
 677         if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
 678                 ieee80211_recalc_chanctx_chantype(local, curr_ctx);
 679                 ieee80211_recalc_smps_chanctx(local, curr_ctx);
 680                 ieee80211_recalc_radar_chanctx(local, curr_ctx);
 681                 ieee80211_recalc_chanctx_min_def(local, curr_ctx);
 682         }
 683
 684         if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
 685                 ieee80211_recalc_txpower(sdata, false);
 686                 ieee80211_recalc_chanctx_min_def(local, new_ctx);
 687         }
 688
 689         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
 690             sdata->vif.type != NL80211_IFTYPE_MONITOR)
 691                 ieee80211_bss_info_change_notify(sdata,
 692                                                  BSS_CHANGED_IDLE);
 693
 694         ieee80211_check_fast_xmit_iface(sdata);
 695
 696         return ret;
 697 }
 698
 699 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 700                                    struct ieee80211_chanctx *chanctx)
 701 {
 702         struct ieee80211_sub_if_data *sdata;
 703         u8 rx_chains_static, rx_chains_dynamic;
 704
 705         lockdep_assert_held(&local->chanctx_mtx);
 706
 707         rx_chains_static = 1;
 708         rx_chains_dynamic = 1;
 709
 710         rcu_read_lock();
 711         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 712                 u8 needed_static, needed_dynamic;
 713
 714                 if (!ieee80211_sdata_running(sdata))
 715                         continue;
 716
 717                 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
 718                                                 &chanctx->conf)
 719                         continue;
 720
 721                 switch (sdata->vif.type) {
 722                 case NL80211_IFTYPE_P2P_DEVICE:
 723                 case NL80211_IFTYPE_NAN:
 724                         continue;
 725                 case NL80211_IFTYPE_STATION:
 726                         if (!sdata->u.mgd.associated)
 727                                 continue;
 728                         break;
 729                 case NL80211_IFTYPE_AP_VLAN:
 730                         continue;
 731                 case NL80211_IFTYPE_AP:
 732                 case NL80211_IFTYPE_ADHOC:
 733                 case NL80211_IFTYPE_WDS:
 734                 case NL80211_IFTYPE_MESH_POINT:
 735                 case NL80211_IFTYPE_OCB:
 736                         break;
 737                 default:
 738                         WARN_ON_ONCE(1);
 739                 }
 740
 741                 switch (sdata->smps_mode) {
 742                 default:
 743                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
 744                                   sdata->smps_mode);
 745                         /* fall through */
 746                 case IEEE80211_SMPS_OFF:
 747                         needed_static = sdata->needed_rx_chains;
 748                         needed_dynamic = sdata->needed_rx_chains;
 749                         break;
 750                 case IEEE80211_SMPS_DYNAMIC:
 751                         needed_static = 1;
 752                         needed_dynamic = sdata->needed_rx_chains;
 753                         break;
 754                 case IEEE80211_SMPS_STATIC:
 755                         needed_static = 1;
 756                         needed_dynamic = 1;
 757                         break;
 758                 }
 759
 760                 rx_chains_static = max(rx_chains_static, needed_static);
 761                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
 762         }
 763
 764         /* Disable SMPS for the monitor interface */
 765         sdata = rcu_dereference(local->monitor_sdata);
 766         if (sdata &&
 767             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
 768                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
 769
 770         rcu_read_unlock();
 771
 772         if (!local->use_chanctx) {
 773                 if (rx_chains_static > 1)
 774                         local->smps_mode = IEEE80211_SMPS_OFF;
 775                 else if (rx_chains_dynamic > 1)
 776                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
 777                 else
 778                         local->smps_mode = IEEE80211_SMPS_STATIC;
 779                 ieee80211_hw_config(local, 0);
 780         }
 781
 782         if (rx_chains_static == chanctx->conf.rx_chains_static &&
 783             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
 784                 return;
 785
 786         chanctx->conf.rx_chains_static = rx_chains_static;
 787         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
 788         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
 789 }
 790
 791 static void
 792 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 793                                       bool clear)
 794 {
 795         struct ieee80211_local *local __maybe_unused = sdata->local;
 796         struct ieee80211_sub_if_data *vlan;
 797         struct ieee80211_chanctx_conf *conf;
 798
 799         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
 800                 return;
 801
 802         lockdep_assert_held(&local->mtx);
 803
 804         /* Check that conf exists, even when clearing this function
 805          * must be called with the AP's channel context still there
 806          * as it would otherwise cause VLANs to have an invalid
 807          * channel context pointer for a while, possibly pointing
 808          * to a channel context that has already been freed.
 809          */
 810         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 811                                          lockdep_is_held(&local->chanctx_mtx));
 812         WARN_ON(!conf);
 813
 814         if (clear)
 815                 conf = NULL;
 816
 817         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 818                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
 819 }
 820
 821 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 822                                          bool clear)
 823 {
 824         struct ieee80211_local *local = sdata->local;
 825
 826         mutex_lock(&local->chanctx_mtx);
 827
 828         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
 829
 830         mutex_unlock(&local->chanctx_mtx);
 831 }
 832
 833 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
 834 {
 835         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
 836
 837         lockdep_assert_held(&sdata->local->chanctx_mtx);
 838
 839         if (WARN_ON(!ctx))
 840                 return -EINVAL;
 841
 842         list_del(&sdata->reserved_chanctx_list);
 843         sdata->reserved_chanctx = NULL;
 844
 845         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
 846                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
 847                         if (WARN_ON(!ctx->replace_ctx))
 848                                 return -EINVAL;
 849
 850                         WARN_ON(ctx->replace_ctx->replace_state !=
 851                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
 852                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
 853
 854                         ctx->replace_ctx->replace_ctx = NULL;
 855                         ctx->replace_ctx->replace_state =
 856                                         IEEE80211_CHANCTX_REPLACE_NONE;
 857
 858                         list_del_rcu(&ctx->list);
 859                         kfree_rcu(ctx, rcu_head);
 860                 } else {
 861                         ieee80211_free_chanctx(sdata->local, ctx);
 862                 }
 863         }
 864
 865         return 0;
 866 }
 867
 868 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
 869                                   const struct cfg80211_chan_def *chandef,
 870                                   enum ieee80211_chanctx_mode mode,
 871                                   bool radar_required)
 872 {
 873         struct ieee80211_local *local = sdata->local;
 874         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
 875
 876         lockdep_assert_held(&local->chanctx_mtx);
 877
 878         curr_ctx = ieee80211_vif_get_chanctx(sdata);
 879         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
 880                 return -ENOTSUPP;
 881
 882         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
 883         if (!new_ctx) {
 884                 if (ieee80211_can_create_new_chanctx(local)) {
 885                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
 886                         if (IS_ERR(new_ctx))
 887                                 return PTR_ERR(new_ctx);
 888                 } else {
 889                         if (!curr_ctx ||
 890                             (curr_ctx->replace_state ==
 891                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 892                             !list_empty(&curr_ctx->reserved_vifs)) {
 893                                 /*
 894                                  * Another vif already requested this context
 895                                  * for a reservation. Find another one hoping
 896                                  * all vifs assigned to it will also switch
 897                                  * soon enough.
 898                                  *
 899                                  * TODO: This needs a little more work as some
 900                                  * cases (more than 2 chanctx capable devices)
 901                                  * may fail which could otherwise succeed
 902                                  * provided some channel context juggling was
 903                                  * performed.
 904                                  *
 905                                  * Consider ctx1..3, vif1..6, each ctx has 2
 906                                  * vifs. vif1 and vif2 from ctx1 request new
 907                                  * different chandefs starting 2 in-place
 908                                  * reserations with ctx4 and ctx5 replacing
 909                                  * ctx1 and ctx2 respectively. Next vif5 and
 910                                  * vif6 from ctx3 reserve ctx4. If vif3 and
 911                                  * vif4 remain on ctx2 as they are then this
 912                                  * fails unless `replace_ctx` from ctx5 is
 913                                  * replaced with ctx3.
 914                                  */
 915                                 list_for_each_entry(ctx, &local->chanctx_list,
 916                                                     list) {
 917                                         if (ctx->replace_state !=
 918                                             IEEE80211_CHANCTX_REPLACE_NONE)
 919                                                 continue;
 920
 921                                         if (!list_empty(&ctx->reserved_vifs))
 922                                                 continue;
 923
 924                                         curr_ctx = ctx;
 925                                         break;
 926                                 }
 927                         }
 928
 929                         /*
 930                          * If that's true then all available contexts already
 931                          * have reservations and cannot be used.
 932                          */
 933                         if (!curr_ctx ||
 934                             (curr_ctx->replace_state ==
 935                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 936                             !list_empty(&curr_ctx->reserved_vifs))
 937                                 return -EBUSY;
 938
 939                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 940                         if (!new_ctx)
 941                                 return -ENOMEM;
 942
 943                         new_ctx->replace_ctx = curr_ctx;
 944                         new_ctx->replace_state =
 945                                         IEEE80211_CHANCTX_REPLACES_OTHER;
 946
 947                         curr_ctx->replace_ctx = new_ctx;
 948                         curr_ctx->replace_state =
 949                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
 950
 951                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
 952                 }
 953         }
 954
 955         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
 956         sdata->reserved_chanctx = new_ctx;
 957         sdata->reserved_chandef = *chandef;
 958         sdata->reserved_radar_required = radar_required;
 959         sdata->reserved_ready = false;
 960
 961         return 0;
 962 }
 963
 964 static void
 965 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
 966 {
 967         switch (sdata->vif.type) {
 968         case NL80211_IFTYPE_ADHOC:
 969         case NL80211_IFTYPE_AP:
 970         case NL80211_IFTYPE_MESH_POINT:
 971         case NL80211_IFTYPE_OCB:
 972                 ieee80211_queue_work(&sdata->local->hw,
 973                                      &sdata->csa_finalize_work);
 974                 break;
 975         case NL80211_IFTYPE_STATION:
 976                 ieee80211_queue_work(&sdata->local->hw,
 977                                      &sdata->u.mgd.chswitch_work);
 978                 break;
 979         case NL80211_IFTYPE_UNSPECIFIED:
 980         case NL80211_IFTYPE_AP_VLAN:
 981         case NL80211_IFTYPE_WDS:
 982         case NL80211_IFTYPE_MONITOR:
 983         case NL80211_IFTYPE_P2P_CLIENT:
 984         case NL80211_IFTYPE_P2P_GO:
 985         case NL80211_IFTYPE_P2P_DEVICE:
 986         case NL80211_IFTYPE_NAN:
 987         case NUM_NL80211_IFTYPES:
 988                 WARN_ON(1);
 989                 break;
 990         }
 991 }
 992
 993 static void
 994 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
 995                              const struct cfg80211_chan_def *chandef)
 996 {
 997         struct ieee80211_sub_if_data *vlan;
 998
 999         sdata->vif.bss_conf.chandef = *chandef;
1000
1001         if (sdata->vif.type != NL80211_IFTYPE_AP)
1002                 return;
1003
1004         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1005                 vlan->vif.bss_conf.chandef = *chandef;
1006 }
1007
1008 static int
1009 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
1010 {
1011         struct ieee80211_local *local = sdata->local;
1012         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1013         struct ieee80211_chanctx *old_ctx, *new_ctx;
1014         const struct cfg80211_chan_def *chandef;
1015         u32 changed = 0;
1016         int err;
1017
1018         lockdep_assert_held(&local->mtx);
1019         lockdep_assert_held(&local->chanctx_mtx);
1020
1021         new_ctx = sdata->reserved_chanctx;
1022         old_ctx = ieee80211_vif_get_chanctx(sdata);
1023
1024         if (WARN_ON(!sdata->reserved_ready))
1025                 return -EBUSY;
1026
1027         if (WARN_ON(!new_ctx))
1028                 return -EINVAL;
1029
1030         if (WARN_ON(!old_ctx))
1031                 return -EINVAL;
1032
1033         if (WARN_ON(new_ctx->replace_state ==
1034                     IEEE80211_CHANCTX_REPLACES_OTHER))
1035                 return -EINVAL;
1036
1037         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1038                                 &sdata->reserved_chandef);
1039         if (WARN_ON(!chandef))
1040                 return -EINVAL;
1041
1042         ieee80211_change_chanctx(local, new_ctx, chandef);
1043
1044         vif_chsw[0].vif = &sdata->vif;
1045         vif_chsw[0].old_ctx = &old_ctx->conf;
1046         vif_chsw[0].new_ctx = &new_ctx->conf;
1047
1048         list_del(&sdata->reserved_chanctx_list);
1049         sdata->reserved_chanctx = NULL;
1050
1051         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1052                                      CHANCTX_SWMODE_REASSIGN_VIF);
1053         if (err) {
1054                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1055                         ieee80211_free_chanctx(local, new_ctx);
1056
1057                 goto out;
1058         }
1059
1060         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1061         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1062
1063         if (sdata->vif.type == NL80211_IFTYPE_AP)
1064                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1065
1066         ieee80211_check_fast_xmit_iface(sdata);
1067
1068         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1069                 ieee80211_free_chanctx(local, old_ctx);
1070
1071         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1072                 changed = BSS_CHANGED_BANDWIDTH;
1073
1074         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1075
1076         ieee80211_recalc_smps_chanctx(local, new_ctx);
1077         ieee80211_recalc_radar_chanctx(local, new_ctx);
1078         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1079
1080         if (changed)
1081                 ieee80211_bss_info_change_notify(sdata, changed);
1082
1083 out:
1084         ieee80211_vif_chanctx_reservation_complete(sdata);
1085         return err;
1086 }
1087
1088 static int
1089 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1090 {
1091         struct ieee80211_local *local = sdata->local;
1092         struct ieee80211_chanctx *old_ctx, *new_ctx;
1093         const struct cfg80211_chan_def *chandef;
1094         int err;
1095
1096         old_ctx = ieee80211_vif_get_chanctx(sdata);
1097         new_ctx = sdata->reserved_chanctx;
1098
1099         if (WARN_ON(!sdata->reserved_ready))
1100                 return -EINVAL;
1101
1102         if (WARN_ON(old_ctx))
1103                 return -EINVAL;
1104
1105         if (WARN_ON(!new_ctx))
1106                 return -EINVAL;
1107
1108         if (WARN_ON(new_ctx->replace_state ==
1109                     IEEE80211_CHANCTX_REPLACES_OTHER))
1110                 return -EINVAL;
1111
1112         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1113                                 &sdata->reserved_chandef);
1114         if (WARN_ON(!chandef))
1115                 return -EINVAL;
1116
1117         ieee80211_change_chanctx(local, new_ctx, chandef);
1118
1119         list_del(&sdata->reserved_chanctx_list);
1120         sdata->reserved_chanctx = NULL;
1121
1122         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1123         if (err) {
1124                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1125                         ieee80211_free_chanctx(local, new_ctx);
1126
1127                 goto out;
1128         }
1129
1130 out:
1131         ieee80211_vif_chanctx_reservation_complete(sdata);
1132         return err;
1133 }
1134
1135 static bool
1136 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1137 {
1138         struct ieee80211_chanctx *old_ctx, *new_ctx;
1139
1140         lockdep_assert_held(&sdata->local->chanctx_mtx);
1141
1142         new_ctx = sdata->reserved_chanctx;
1143         old_ctx = ieee80211_vif_get_chanctx(sdata);
1144
1145         if (!old_ctx)
1146                 return false;
1147
1148         if (WARN_ON(!new_ctx))
1149                 return false;
1150
1151         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1152                 return false;
1153
1154         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1155                 return false;
1156
1157         return true;
1158 }
1159
1160 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1161                                         struct ieee80211_chanctx *new_ctx)
1162 {
1163         const struct cfg80211_chan_def *chandef;
1164
1165         lockdep_assert_held(&local->mtx);
1166         lockdep_assert_held(&local->chanctx_mtx);
1167
1168         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1169         if (WARN_ON(!chandef))
1170                 return -EINVAL;
1171
1172         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1173         local->_oper_chandef = *chandef;
1174         ieee80211_hw_config(local, 0);
1175
1176         return 0;
1177 }
1178
1179 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1180                                       int n_vifs)
1181 {
1182         struct ieee80211_vif_chanctx_switch *vif_chsw;
1183         struct ieee80211_sub_if_data *sdata;
1184         struct ieee80211_chanctx *ctx, *old_ctx;
1185         int i, err;
1186
1187         lockdep_assert_held(&local->mtx);
1188         lockdep_assert_held(&local->chanctx_mtx);
1189
1190         vif_chsw = kcalloc(n_vifs, sizeof(vif_chsw[0]), GFP_KERNEL);
1191         if (!vif_chsw)
1192                 return -ENOMEM;
1193
1194         i = 0;
1195         list_for_each_entry(ctx, &local->chanctx_list, list) {
1196                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1197                         continue;
1198
1199                 if (WARN_ON(!ctx->replace_ctx)) {
1200                         err = -EINVAL;
1201                         goto out;
1202                 }
1203
1204                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1205                                     reserved_chanctx_list) {
1206                         if (!ieee80211_vif_has_in_place_reservation(
1207                                         sdata))
1208                                 continue;
1209
1210                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1211                         vif_chsw[i].vif = &sdata->vif;
1212                         vif_chsw[i].old_ctx = &old_ctx->conf;
1213                         vif_chsw[i].new_ctx = &ctx->conf;
1214
1215                         i++;
1216                 }
1217         }
1218
1219         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1220                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1221
1222 out:
1223         kfree(vif_chsw);
1224         return err;
1225 }
1226
1227 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1228 {
1229         struct ieee80211_chanctx *ctx;
1230         int err;
1231
1232         lockdep_assert_held(&local->mtx);
1233         lockdep_assert_held(&local->chanctx_mtx);
1234
1235         list_for_each_entry(ctx, &local->chanctx_list, list) {
1236                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1237                         continue;
1238
1239                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1240                         continue;
1241
1242                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1243                 err = ieee80211_add_chanctx(local, ctx);
1244                 if (err)
1245                         goto err;
1246         }
1247
1248         return 0;
1249
1250 err:
1251         WARN_ON(ieee80211_add_chanctx(local, ctx));
1252         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1253                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1254                         continue;
1255
1256                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1257                         continue;
1258
1259                 ieee80211_del_chanctx(local, ctx);
1260                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1261         }
1262
1263         return err;
1264 }
1265
1266 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1267 {
1268         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1269         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1270         struct ieee80211_chanctx *new_ctx = NULL;
1271         int err, n_assigned, n_reserved, n_ready;
1272         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1273
1274         lockdep_assert_held(&local->mtx);
1275         lockdep_assert_held(&local->chanctx_mtx);
1276
1277         /*
1278          * If there are 2 independent pairs of channel contexts performing
1279          * cross-switch of their vifs this code will still wait until both are
1280          * ready even though it could be possible to switch one before the
1281          * other is ready.
1282          *
1283          * For practical reasons and code simplicity just do a single huge
1284          * switch.
1285          */
1286
1287         /*
1288          * Verify if the reservation is still feasible.
1289          *  - if it's not then disconnect
1290          *  - if it is but not all vifs necessary are ready then defer
1291          */
1292
1293         list_for_each_entry(ctx, &local->chanctx_list, list) {
1294                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1295                         continue;
1296
1297                 if (WARN_ON(!ctx->replace_ctx)) {
1298                         err = -EINVAL;
1299                         goto err;
1300                 }
1301
1302                 if (!local->use_chanctx)
1303                         new_ctx = ctx;
1304
1305                 n_ctx++;
1306
1307                 n_assigned = 0;
1308                 n_reserved = 0;
1309                 n_ready = 0;
1310
1311                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1312                                     assigned_chanctx_list) {
1313                         n_assigned++;
1314                         if (sdata->reserved_chanctx) {
1315                                 n_reserved++;
1316                                 if (sdata->reserved_ready)
1317                                         n_ready++;
1318                         }
1319                 }
1320
1321                 if (n_assigned != n_reserved) {
1322                         if (n_ready == n_reserved) {
1323                                 wiphy_info(local->hw.wiphy,
1324                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1325                                 err = -EBUSY;
1326                                 goto err;
1327                         }
1328
1329                         return -EAGAIN;
1330                 }
1331
1332                 ctx->conf.radar_enabled = false;
1333                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1334                                     reserved_chanctx_list) {
1335                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1336                             !sdata->reserved_ready)
1337                                 return -EAGAIN;
1338
1339                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1340                         if (old_ctx) {
1341                                 if (old_ctx->replace_state ==
1342                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1343                                         n_vifs_switch++;
1344                                 else
1345                                         n_vifs_assign++;
1346                         } else {
1347                                 n_vifs_ctxless++;
1348                         }
1349
1350                         if (sdata->reserved_radar_required)
1351                                 ctx->conf.radar_enabled = true;
1352                 }
1353         }
1354
1355         if (WARN_ON(n_ctx == 0) ||
1356             WARN_ON(n_vifs_switch == 0 &&
1357                     n_vifs_assign == 0 &&
1358                     n_vifs_ctxless == 0) ||
1359             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1360             WARN_ON(!new_ctx && !local->use_chanctx)) {
1361                 err = -EINVAL;
1362                 goto err;
1363         }
1364
1365         /*
1366          * All necessary vifs are ready. Perform the switch now depending on
1367          * reservations and driver capabilities.
1368          */
1369
1370         if (local->use_chanctx) {
1371                 if (n_vifs_switch > 0) {
1372                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1373                         if (err)
1374                                 goto err;
1375                 }
1376
1377                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1378                         err = ieee80211_chsw_switch_ctxs(local);
1379                         if (err)
1380                                 goto err;
1381                 }
1382         } else {
1383                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1384                 if (err)
1385                         goto err;
1386         }
1387
1388         /*
1389          * Update all structures, values and pointers to point to new channel
1390          * context(s).
1391          */
1392         list_for_each_entry(ctx, &local->chanctx_list, list) {
1393                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1394                         continue;
1395
1396                 if (WARN_ON(!ctx->replace_ctx)) {
1397                         err = -EINVAL;
1398                         goto err;
1399                 }
1400
1401                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1402                                     reserved_chanctx_list) {
1403                         u32 changed = 0;
1404
1405                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1406                                 continue;
1407
1408                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1409
1410                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1411                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1412                                                                       false);
1413
1414                         ieee80211_check_fast_xmit_iface(sdata);
1415
1416                         sdata->radar_required = sdata->reserved_radar_required;
1417
1418                         if (sdata->vif.bss_conf.chandef.width !=
1419                             sdata->reserved_chandef.width)
1420                                 changed = BSS_CHANGED_BANDWIDTH;
1421
1422                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1423                         if (changed)
1424                                 ieee80211_bss_info_change_notify(sdata,
1425                                                                  changed);
1426
1427                         ieee80211_recalc_txpower(sdata, false);
1428                 }
1429
1430                 ieee80211_recalc_chanctx_chantype(local, ctx);
1431                 ieee80211_recalc_smps_chanctx(local, ctx);
1432                 ieee80211_recalc_radar_chanctx(local, ctx);
1433                 ieee80211_recalc_chanctx_min_def(local, ctx);
1434
1435                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1436                                          reserved_chanctx_list) {
1437                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1438                                 continue;
1439
1440                         list_del(&sdata->reserved_chanctx_list);
1441                         list_move(&sdata->assigned_chanctx_list,
1442                                   &ctx->assigned_vifs);
1443                         sdata->reserved_chanctx = NULL;
1444
1445                         ieee80211_vif_chanctx_reservation_complete(sdata);
1446                 }
1447
1448                 /*
1449                  * This context might have been a dependency for an already
1450                  * ready re-assign reservation interface that was deferred. Do
1451                  * not propagate error to the caller though. The in-place
1452                  * reservation for originally requested interface has already
1453                  * succeeded at this point.
1454                  */
1455                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1456                                          reserved_chanctx_list) {
1457                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1458                                         sdata)))
1459                                 continue;
1460
1461                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1462                                 continue;
1463
1464                         if (!sdata->reserved_ready)
1465                                 continue;
1466
1467                         if (ieee80211_vif_get_chanctx(sdata))
1468                                 err = ieee80211_vif_use_reserved_reassign(
1469                                                 sdata);
1470                         else
1471                                 err = ieee80211_vif_use_reserved_assign(sdata);
1472
1473                         if (err) {
1474                                 sdata_info(sdata,
1475                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1476                                            err);
1477                                 ieee80211_vif_unreserve_chanctx(sdata);
1478                                 cfg80211_stop_iface(local->hw.wiphy,
1479                                                     &sdata->wdev,
1480                                                     GFP_KERNEL);
1481                         }
1482                 }
1483         }
1484
1485         /*
1486          * Finally free old contexts
1487          */
1488
1489         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1490                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1491                         continue;
1492
1493                 ctx->replace_ctx->replace_ctx = NULL;
1494                 ctx->replace_ctx->replace_state =
1495                                 IEEE80211_CHANCTX_REPLACE_NONE;
1496
1497                 list_del_rcu(&ctx->list);
1498                 kfree_rcu(ctx, rcu_head);
1499         }
1500
1501         return 0;
1502
1503 err:
1504         list_for_each_entry(ctx, &local->chanctx_list, list) {
1505                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1506                         continue;
1507
1508                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1509                                          reserved_chanctx_list) {
1510                         ieee80211_vif_unreserve_chanctx(sdata);
1511                         ieee80211_vif_chanctx_reservation_complete(sdata);
1512                 }
1513         }
1514
1515         return err;
1516 }
1517
1518 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1519 {
1520         struct ieee80211_local *local = sdata->local;
1521         struct ieee80211_chanctx_conf *conf;
1522         struct ieee80211_chanctx *ctx;
1523         bool use_reserved_switch = false;
1524
1525         lockdep_assert_held(&local->chanctx_mtx);
1526
1527         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1528                                          lockdep_is_held(&local->chanctx_mtx));
1529         if (!conf)
1530                 return;
1531
1532         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1533
1534         if (sdata->reserved_chanctx) {
1535                 if (sdata->reserved_chanctx->replace_state ==
1536                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1537                     ieee80211_chanctx_num_reserved(local,
1538                                                    sdata->reserved_chanctx) > 1)
1539                         use_reserved_switch = true;
1540
1541                 ieee80211_vif_unreserve_chanctx(sdata);
1542         }
1543
1544         ieee80211_assign_vif_chanctx(sdata, NULL);
1545         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1546                 ieee80211_free_chanctx(local, ctx);
1547
1548         sdata->radar_required = false;
1549
1550         /* Unreserving may ready an in-place reservation. */
1551         if (use_reserved_switch)
1552                 ieee80211_vif_use_reserved_switch(local);
1553 }
1554
1555 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1556                               const struct cfg80211_chan_def *chandef,
1557                               enum ieee80211_chanctx_mode mode)
1558 {
1559         struct ieee80211_local *local = sdata->local;
1560         struct ieee80211_chanctx *ctx;
1561         u8 radar_detect_width = 0;
1562         int ret;
1563
1564         lockdep_assert_held(&local->mtx);
1565
1566         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1567
1568         mutex_lock(&local->chanctx_mtx);
1569
1570         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1571                                             chandef,
1572                                             sdata->wdev.iftype);
1573         if (ret < 0)
1574                 goto out;
1575         if (ret > 0)
1576                 radar_detect_width = BIT(chandef->width);
1577
1578         sdata->radar_required = ret;
1579
1580         ret = ieee80211_check_combinations(sdata, chandef, mode,
1581                                            radar_detect_width);
1582         if (ret < 0)
1583                 goto out;
1584
1585         __ieee80211_vif_release_channel(sdata);
1586
1587         ctx = ieee80211_find_chanctx(local, chandef, mode);
1588         if (!ctx)
1589                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1590         if (IS_ERR(ctx)) {
1591                 ret = PTR_ERR(ctx);
1592                 goto out;
1593         }
1594
1595         ieee80211_vif_update_chandef(sdata, chandef);
1596
1597         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1598         if (ret) {
1599                 /* if assign fails refcount stays the same */
1600                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1601                         ieee80211_free_chanctx(local, ctx);
1602                 goto out;
1603         }
1604
1605         ieee80211_recalc_smps_chanctx(local, ctx);
1606         ieee80211_recalc_radar_chanctx(local, ctx);
1607  out:
1608         if (ret)
1609                 sdata->radar_required = false;
1610
1611         mutex_unlock(&local->chanctx_mtx);
1612         return ret;
1613 }
1614
1615 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1616 {
1617         struct ieee80211_local *local = sdata->local;
1618         struct ieee80211_chanctx *new_ctx;
1619         struct ieee80211_chanctx *old_ctx;
1620         int err;
1621
1622         lockdep_assert_held(&local->mtx);
1623         lockdep_assert_held(&local->chanctx_mtx);
1624
1625         new_ctx = sdata->reserved_chanctx;
1626         old_ctx = ieee80211_vif_get_chanctx(sdata);
1627
1628         if (WARN_ON(!new_ctx))
1629                 return -EINVAL;
1630
1631         if (WARN_ON(new_ctx->replace_state ==
1632                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1633                 return -EINVAL;
1634
1635         if (WARN_ON(sdata->reserved_ready))
1636                 return -EINVAL;
1637
1638         sdata->reserved_ready = true;
1639
1640         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1641                 if (old_ctx)
1642                         err = ieee80211_vif_use_reserved_reassign(sdata);
1643                 else
1644                         err = ieee80211_vif_use_reserved_assign(sdata);
1645
1646                 if (err)
1647                         return err;
1648         }
1649
1650         /*
1651          * In-place reservation may need to be finalized now either if:
1652          *  a) sdata is taking part in the swapping itself and is the last one
1653          *  b) sdata has switched with a re-assign reservation to an existing
1654          *     context readying in-place switching of old_ctx
1655          *
1656          * In case of (b) do not propagate the error up because the requested
1657          * sdata already switched successfully. Just spill an extra warning.
1658          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1659          * interfaces upon failure.
1660          */
1661         if ((old_ctx &&
1662              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1663             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1664                 err = ieee80211_vif_use_reserved_switch(local);
1665                 if (err && err != -EAGAIN) {
1666                         if (new_ctx->replace_state ==
1667                             IEEE80211_CHANCTX_REPLACES_OTHER)
1668                                 return err;
1669
1670                         wiphy_info(local->hw.wiphy,
1671                                    "depending in-place reservation failed (err=%d)\n",
1672                                    err);
1673                 }
1674         }
1675
1676         return 0;
1677 }
1678
1679 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1680                                    const struct cfg80211_chan_def *chandef,
1681                                    u32 *changed)
1682 {
1683         struct ieee80211_local *local = sdata->local;
1684         struct ieee80211_chanctx_conf *conf;
1685         struct ieee80211_chanctx *ctx;
1686         const struct cfg80211_chan_def *compat;
1687         int ret;
1688
1689         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1690                                      IEEE80211_CHAN_DISABLED))
1691                 return -EINVAL;
1692
1693         mutex_lock(&local->chanctx_mtx);
1694         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1695                 ret = 0;
1696                 goto out;
1697         }
1698
1699         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1700             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1701                 ret = -EINVAL;
1702                 goto out;
1703         }
1704
1705         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1706                                          lockdep_is_held(&local->chanctx_mtx));
1707         if (!conf) {
1708                 ret = -EINVAL;
1709                 goto out;
1710         }
1711
1712         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1713
1714         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1715         if (!compat) {
1716                 ret = -EINVAL;
1717                 goto out;
1718         }
1719
1720         switch (ctx->replace_state) {
1721         case IEEE80211_CHANCTX_REPLACE_NONE:
1722                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1723                         ret = -EBUSY;
1724                         goto out;
1725                 }
1726                 break;
1727         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1728                 /* TODO: Perhaps the bandwidth change could be treated as a
1729                  * reservation itself? */
1730                 ret = -EBUSY;
1731                 goto out;
1732         case IEEE80211_CHANCTX_REPLACES_OTHER:
1733                 /* channel context that is going to replace another channel
1734                  * context doesn't really exist and shouldn't be assigned
1735                  * anywhere yet */
1736                 WARN_ON(1);
1737                 break;
1738         }
1739
1740         ieee80211_vif_update_chandef(sdata, chandef);
1741
1742         ieee80211_recalc_chanctx_chantype(local, ctx);
1743
1744         *changed |= BSS_CHANGED_BANDWIDTH;
1745         ret = 0;
1746  out:
1747         mutex_unlock(&local->chanctx_mtx);
1748         return ret;
1749 }
1750
1751 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1752 {
1753         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1754
1755         lockdep_assert_held(&sdata->local->mtx);
1756
1757         mutex_lock(&sdata->local->chanctx_mtx);
1758         __ieee80211_vif_release_channel(sdata);
1759         mutex_unlock(&sdata->local->chanctx_mtx);
1760 }
1761
1762 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1763 {
1764         struct ieee80211_local *local = sdata->local;
1765         struct ieee80211_sub_if_data *ap;
1766         struct ieee80211_chanctx_conf *conf;
1767
1768         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1769                 return;
1770
1771         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1772
1773         mutex_lock(&local->chanctx_mtx);
1774
1775         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1776                                          lockdep_is_held(&local->chanctx_mtx));
1777         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1778         mutex_unlock(&local->chanctx_mtx);
1779 }
1780
1781 void ieee80211_iter_chan_contexts_atomic(
1782         struct ieee80211_hw *hw,
1783         void (*iter)(struct ieee80211_hw *hw,
1784                      struct ieee80211_chanctx_conf *chanctx_conf,
1785                      void *data),
1786         void *iter_data)
1787 {
1788         struct ieee80211_local *local = hw_to_local(hw);
1789         struct ieee80211_chanctx *ctx;
1790
1791         rcu_read_lock();
1792         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1793                 if (ctx->driver_present)
1794                         iter(hw, &ctx->conf, iter_data);
1795         rcu_read_unlock();
1796 }
1797 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);