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