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_MESH_POINT:
 279                 case NL80211_IFTYPE_OCB:
 280                         width = vif->bss_conf.chandef.width;
 281                         break;
 282                 case NL80211_IFTYPE_WDS:
 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 non-20MHz based 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.def.width == NL80211_CHAN_WIDTH_1 ||
 320             ctx->conf.def.width == NL80211_CHAN_WIDTH_2 ||
 321             ctx->conf.def.width == NL80211_CHAN_WIDTH_4 ||
 322             ctx->conf.def.width == NL80211_CHAN_WIDTH_8 ||
 323             ctx->conf.def.width == NL80211_CHAN_WIDTH_16 ||
 324             ctx->conf.radar_enabled) {
 325                 ctx->conf.min_def = ctx->conf.def;
 326                 return;
 327         }
 328
 329         max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
 330
 331         /* downgrade chandef up to max_bw */
 332         min_def = ctx->conf.def;
 333         while (min_def.width > max_bw)
 334                 ieee80211_chandef_downgrade(&min_def);
 335
 336         if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
 337                 return;
 338
 339         ctx->conf.min_def = min_def;
 340         if (!ctx->driver_present)
 341                 return;
 342
 343         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
 344 }
 345
 346 static void ieee80211_change_chanctx(struct ieee80211_local *local,
 347                                      struct ieee80211_chanctx *ctx,
 348                                      const struct cfg80211_chan_def *chandef)
 349 {
 350         if (cfg80211_chandef_identical(&ctx->conf.def, chandef)) {
 351                 ieee80211_recalc_chanctx_min_def(local, ctx);
 352                 return;
 353         }
 354
 355         WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
 356
 357         ctx->conf.def = *chandef;
 358         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
 359         ieee80211_recalc_chanctx_min_def(local, ctx);
 360
 361         if (!local->use_chanctx) {
 362                 local->_oper_chandef = *chandef;
 363                 ieee80211_hw_config(local, 0);
 364         }
 365 }
 366
 367 static struct ieee80211_chanctx *
 368 ieee80211_find_chanctx(struct ieee80211_local *local,
 369                        const struct cfg80211_chan_def *chandef,
 370                        enum ieee80211_chanctx_mode mode)
 371 {
 372         struct ieee80211_chanctx *ctx;
 373
 374         lockdep_assert_held(&local->chanctx_mtx);
 375
 376         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 377                 return NULL;
 378
 379         list_for_each_entry(ctx, &local->chanctx_list, list) {
 380                 const struct cfg80211_chan_def *compat;
 381
 382                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
 383                         continue;
 384
 385                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 386                         continue;
 387
 388                 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
 389                 if (!compat)
 390                         continue;
 391
 392                 compat = ieee80211_chanctx_reserved_chandef(local, ctx,
 393                                                             compat);
 394                 if (!compat)
 395                         continue;
 396
 397                 ieee80211_change_chanctx(local, ctx, compat);
 398
 399                 return ctx;
 400         }
 401
 402         return NULL;
 403 }
 404
 405 bool ieee80211_is_radar_required(struct ieee80211_local *local)
 406 {
 407         struct ieee80211_sub_if_data *sdata;
 408
 409         lockdep_assert_held(&local->mtx);
 410
 411         rcu_read_lock();
 412         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 413                 if (sdata->radar_required) {
 414                         rcu_read_unlock();
 415                         return true;
 416                 }
 417         }
 418         rcu_read_unlock();
 419
 420         return false;
 421 }
 422
 423 static bool
 424 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
 425                                  struct ieee80211_chanctx *ctx)
 426 {
 427         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 428         struct ieee80211_sub_if_data *sdata;
 429         bool required = false;
 430
 431         lockdep_assert_held(&local->chanctx_mtx);
 432         lockdep_assert_held(&local->mtx);
 433
 434         rcu_read_lock();
 435         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 436                 if (!ieee80211_sdata_running(sdata))
 437                         continue;
 438                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 439                         continue;
 440                 if (!sdata->radar_required)
 441                         continue;
 442
 443                 required = true;
 444                 break;
 445         }
 446         rcu_read_unlock();
 447
 448         return required;
 449 }
 450
 451 static struct ieee80211_chanctx *
 452 ieee80211_alloc_chanctx(struct ieee80211_local *local,
 453                         const struct cfg80211_chan_def *chandef,
 454                         enum ieee80211_chanctx_mode mode)
 455 {
 456         struct ieee80211_chanctx *ctx;
 457
 458         lockdep_assert_held(&local->chanctx_mtx);
 459
 460         ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
 461         if (!ctx)
 462                 return NULL;
 463
 464         INIT_LIST_HEAD(&ctx->assigned_vifs);
 465         INIT_LIST_HEAD(&ctx->reserved_vifs);
 466         ctx->conf.def = *chandef;
 467         ctx->conf.rx_chains_static = 1;
 468         ctx->conf.rx_chains_dynamic = 1;
 469         ctx->mode = mode;
 470         ctx->conf.radar_enabled = false;
 471         ieee80211_recalc_chanctx_min_def(local, ctx);
 472
 473         return ctx;
 474 }
 475
 476 static int ieee80211_add_chanctx(struct ieee80211_local *local,
 477                                  struct ieee80211_chanctx *ctx)
 478 {
 479         u32 changed;
 480         int err;
 481
 482         lockdep_assert_held(&local->mtx);
 483         lockdep_assert_held(&local->chanctx_mtx);
 484
 485         if (!local->use_chanctx)
 486                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 487
 488         /* turn idle off *before* setting channel -- some drivers need that */
 489         changed = ieee80211_idle_off(local);
 490         if (changed)
 491                 ieee80211_hw_config(local, changed);
 492
 493         if (!local->use_chanctx) {
 494                 local->_oper_chandef = ctx->conf.def;
 495                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 496         } else {
 497                 err = drv_add_chanctx(local, ctx);
 498                 if (err) {
 499                         ieee80211_recalc_idle(local);
 500                         return err;
 501                 }
 502         }
 503
 504         return 0;
 505 }
 506
 507 static struct ieee80211_chanctx *
 508 ieee80211_new_chanctx(struct ieee80211_local *local,
 509                       const struct cfg80211_chan_def *chandef,
 510                       enum ieee80211_chanctx_mode mode)
 511 {
 512         struct ieee80211_chanctx *ctx;
 513         int err;
 514
 515         lockdep_assert_held(&local->mtx);
 516         lockdep_assert_held(&local->chanctx_mtx);
 517
 518         ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 519         if (!ctx)
 520                 return ERR_PTR(-ENOMEM);
 521
 522         err = ieee80211_add_chanctx(local, ctx);
 523         if (err) {
 524                 kfree(ctx);
 525                 return ERR_PTR(err);
 526         }
 527
 528         list_add_rcu(&ctx->list, &local->chanctx_list);
 529         return ctx;
 530 }
 531
 532 static void ieee80211_del_chanctx(struct ieee80211_local *local,
 533                                   struct ieee80211_chanctx *ctx)
 534 {
 535         lockdep_assert_held(&local->chanctx_mtx);
 536
 537         if (!local->use_chanctx) {
 538                 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
 539                 /* S1G doesn't have 20MHz, so get the correct width for the
 540                  * current channel.
 541                  */
 542                 if (chandef->chan->band == NL80211_BAND_S1GHZ)
 543                         chandef->width =
 544                                 ieee80211_s1g_channel_width(chandef->chan);
 545                 else
 546                         chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 547                 chandef->center_freq1 = chandef->chan->center_freq;
 548                 chandef->freq1_offset = chandef->chan->freq_offset;
 549                 chandef->center_freq2 = 0;
 550
 551                 /* NOTE: Disabling radar is only valid here for
 552                  * single channel context. To be sure, check it ...
 553                  */
 554                 WARN_ON(local->hw.conf.radar_enabled &&
 555                         !list_empty(&local->chanctx_list));
 556
 557                 local->hw.conf.radar_enabled = false;
 558
 559                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 560         } else {
 561                 drv_remove_chanctx(local, ctx);
 562         }
 563
 564         ieee80211_recalc_idle(local);
 565 }
 566
 567 static void ieee80211_free_chanctx(struct ieee80211_local *local,
 568                                    struct ieee80211_chanctx *ctx)
 569 {
 570         lockdep_assert_held(&local->chanctx_mtx);
 571
 572         WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
 573
 574         list_del_rcu(&ctx->list);
 575         ieee80211_del_chanctx(local, ctx);
 576         kfree_rcu(ctx, rcu_head);
 577 }
 578
 579 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 580                                        struct ieee80211_chanctx *ctx)
 581 {
 582         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 583         struct ieee80211_sub_if_data *sdata;
 584         const struct cfg80211_chan_def *compat = NULL;
 585         struct sta_info *sta;
 586
 587         lockdep_assert_held(&local->chanctx_mtx);
 588
 589         rcu_read_lock();
 590         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 591
 592                 if (!ieee80211_sdata_running(sdata))
 593                         continue;
 594                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 595                         continue;
 596                 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 597                         continue;
 598
 599                 if (!compat)
 600                         compat = &sdata->vif.bss_conf.chandef;
 601
 602                 compat = cfg80211_chandef_compatible(
 603                                 &sdata->vif.bss_conf.chandef, compat);
 604                 if (WARN_ON_ONCE(!compat))
 605                         break;
 606         }
 607
 608         /* TDLS peers can sometimes affect the chandef width */
 609         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 610                 if (!sta->uploaded ||
 611                     !test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW) ||
 612                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
 613                     !sta->tdls_chandef.chan)
 614                         continue;
 615
 616                 compat = cfg80211_chandef_compatible(&sta->tdls_chandef,
 617                                                      compat);
 618                 if (WARN_ON_ONCE(!compat))
 619                         break;
 620         }
 621         rcu_read_unlock();
 622
 623         if (!compat)
 624                 return;
 625
 626         ieee80211_change_chanctx(local, ctx, compat);
 627 }
 628
 629 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
 630                                            struct ieee80211_chanctx *chanctx)
 631 {
 632         bool radar_enabled;
 633
 634         lockdep_assert_held(&local->chanctx_mtx);
 635         /* for ieee80211_is_radar_required */
 636         lockdep_assert_held(&local->mtx);
 637
 638         radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
 639
 640         if (radar_enabled == chanctx->conf.radar_enabled)
 641                 return;
 642
 643         chanctx->conf.radar_enabled = radar_enabled;
 644
 645         if (!local->use_chanctx) {
 646                 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
 647                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 648         }
 649
 650         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
 651 }
 652
 653 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 654                                         struct ieee80211_chanctx *new_ctx)
 655 {
 656         struct ieee80211_local *local = sdata->local;
 657         struct ieee80211_chanctx_conf *conf;
 658         struct ieee80211_chanctx *curr_ctx = NULL;
 659         int ret = 0;
 660
 661         if (WARN_ON(sdata->vif.type == NL80211_IFTYPE_NAN))
 662                 return -ENOTSUPP;
 663
 664         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 665                                          lockdep_is_held(&local->chanctx_mtx));
 666
 667         if (conf) {
 668                 curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
 669
 670                 drv_unassign_vif_chanctx(local, sdata, curr_ctx);
 671                 conf = NULL;
 672                 list_del(&sdata->assigned_chanctx_list);
 673         }
 674
 675         if (new_ctx) {
 676                 ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
 677                 if (ret)
 678                         goto out;
 679
 680                 conf = &new_ctx->conf;
 681                 list_add(&sdata->assigned_chanctx_list,
 682                          &new_ctx->assigned_vifs);
 683         }
 684
 685 out:
 686         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
 687
 688         sdata->vif.bss_conf.idle = !conf;
 689
 690         if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
 691                 ieee80211_recalc_chanctx_chantype(local, curr_ctx);
 692                 ieee80211_recalc_smps_chanctx(local, curr_ctx);
 693                 ieee80211_recalc_radar_chanctx(local, curr_ctx);
 694                 ieee80211_recalc_chanctx_min_def(local, curr_ctx);
 695         }
 696
 697         if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
 698                 ieee80211_recalc_txpower(sdata, false);
 699                 ieee80211_recalc_chanctx_min_def(local, new_ctx);
 700         }
 701
 702         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
 703             sdata->vif.type != NL80211_IFTYPE_MONITOR)
 704                 ieee80211_bss_info_change_notify(sdata,
 705                                                  BSS_CHANGED_IDLE);
 706
 707         ieee80211_check_fast_xmit_iface(sdata);
 708
 709         return ret;
 710 }
 711
 712 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 713                                    struct ieee80211_chanctx *chanctx)
 714 {
 715         struct ieee80211_sub_if_data *sdata;
 716         u8 rx_chains_static, rx_chains_dynamic;
 717
 718         lockdep_assert_held(&local->chanctx_mtx);
 719
 720         rx_chains_static = 1;
 721         rx_chains_dynamic = 1;
 722
 723         rcu_read_lock();
 724         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 725                 u8 needed_static, needed_dynamic;
 726
 727                 if (!ieee80211_sdata_running(sdata))
 728                         continue;
 729
 730                 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
 731                                                 &chanctx->conf)
 732                         continue;
 733
 734                 switch (sdata->vif.type) {
 735                 case NL80211_IFTYPE_P2P_DEVICE:
 736                 case NL80211_IFTYPE_NAN:
 737                         continue;
 738                 case NL80211_IFTYPE_STATION:
 739                         if (!sdata->u.mgd.associated)
 740                                 continue;
 741                         break;
 742                 case NL80211_IFTYPE_AP_VLAN:
 743                         continue;
 744                 case NL80211_IFTYPE_AP:
 745                 case NL80211_IFTYPE_ADHOC:
 746                 case NL80211_IFTYPE_MESH_POINT:
 747                 case NL80211_IFTYPE_OCB:
 748                         break;
 749                 default:
 750                         WARN_ON_ONCE(1);
 751                 }
 752
 753                 switch (sdata->smps_mode) {
 754                 default:
 755                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
 756                                   sdata->smps_mode);
 757                         fallthrough;
 758                 case IEEE80211_SMPS_OFF:
 759                         needed_static = sdata->needed_rx_chains;
 760                         needed_dynamic = sdata->needed_rx_chains;
 761                         break;
 762                 case IEEE80211_SMPS_DYNAMIC:
 763                         needed_static = 1;
 764                         needed_dynamic = sdata->needed_rx_chains;
 765                         break;
 766                 case IEEE80211_SMPS_STATIC:
 767                         needed_static = 1;
 768                         needed_dynamic = 1;
 769                         break;
 770                 }
 771
 772                 rx_chains_static = max(rx_chains_static, needed_static);
 773                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
 774         }
 775
 776         /* Disable SMPS for the monitor interface */
 777         sdata = rcu_dereference(local->monitor_sdata);
 778         if (sdata &&
 779             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
 780                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
 781
 782         rcu_read_unlock();
 783
 784         if (!local->use_chanctx) {
 785                 if (rx_chains_static > 1)
 786                         local->smps_mode = IEEE80211_SMPS_OFF;
 787                 else if (rx_chains_dynamic > 1)
 788                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
 789                 else
 790                         local->smps_mode = IEEE80211_SMPS_STATIC;
 791                 ieee80211_hw_config(local, 0);
 792         }
 793
 794         if (rx_chains_static == chanctx->conf.rx_chains_static &&
 795             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
 796                 return;
 797
 798         chanctx->conf.rx_chains_static = rx_chains_static;
 799         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
 800         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
 801 }
 802
 803 static void
 804 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 805                                       bool clear)
 806 {
 807         struct ieee80211_local *local __maybe_unused = sdata->local;
 808         struct ieee80211_sub_if_data *vlan;
 809         struct ieee80211_chanctx_conf *conf;
 810
 811         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
 812                 return;
 813
 814         lockdep_assert_held(&local->mtx);
 815
 816         /* Check that conf exists, even when clearing this function
 817          * must be called with the AP's channel context still there
 818          * as it would otherwise cause VLANs to have an invalid
 819          * channel context pointer for a while, possibly pointing
 820          * to a channel context that has already been freed.
 821          */
 822         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 823                                          lockdep_is_held(&local->chanctx_mtx));
 824         WARN_ON(!conf);
 825
 826         if (clear)
 827                 conf = NULL;
 828
 829         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 830                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
 831 }
 832
 833 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 834                                          bool clear)
 835 {
 836         struct ieee80211_local *local = sdata->local;
 837
 838         mutex_lock(&local->chanctx_mtx);
 839
 840         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
 841
 842         mutex_unlock(&local->chanctx_mtx);
 843 }
 844
 845 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
 846 {
 847         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
 848
 849         lockdep_assert_held(&sdata->local->chanctx_mtx);
 850
 851         if (WARN_ON(!ctx))
 852                 return -EINVAL;
 853
 854         list_del(&sdata->reserved_chanctx_list);
 855         sdata->reserved_chanctx = NULL;
 856
 857         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
 858                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
 859                         if (WARN_ON(!ctx->replace_ctx))
 860                                 return -EINVAL;
 861
 862                         WARN_ON(ctx->replace_ctx->replace_state !=
 863                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
 864                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
 865
 866                         ctx->replace_ctx->replace_ctx = NULL;
 867                         ctx->replace_ctx->replace_state =
 868                                         IEEE80211_CHANCTX_REPLACE_NONE;
 869
 870                         list_del_rcu(&ctx->list);
 871                         kfree_rcu(ctx, rcu_head);
 872                 } else {
 873                         ieee80211_free_chanctx(sdata->local, ctx);
 874                 }
 875         }
 876
 877         return 0;
 878 }
 879
 880 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
 881                                   const struct cfg80211_chan_def *chandef,
 882                                   enum ieee80211_chanctx_mode mode,
 883                                   bool radar_required)
 884 {
 885         struct ieee80211_local *local = sdata->local;
 886         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
 887
 888         lockdep_assert_held(&local->chanctx_mtx);
 889
 890         curr_ctx = ieee80211_vif_get_chanctx(sdata);
 891         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
 892                 return -ENOTSUPP;
 893
 894         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
 895         if (!new_ctx) {
 896                 if (ieee80211_can_create_new_chanctx(local)) {
 897                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
 898                         if (IS_ERR(new_ctx))
 899                                 return PTR_ERR(new_ctx);
 900                 } else {
 901                         if (!curr_ctx ||
 902                             (curr_ctx->replace_state ==
 903                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 904                             !list_empty(&curr_ctx->reserved_vifs)) {
 905                                 /*
 906                                  * Another vif already requested this context
 907                                  * for a reservation. Find another one hoping
 908                                  * all vifs assigned to it will also switch
 909                                  * soon enough.
 910                                  *
 911                                  * TODO: This needs a little more work as some
 912                                  * cases (more than 2 chanctx capable devices)
 913                                  * may fail which could otherwise succeed
 914                                  * provided some channel context juggling was
 915                                  * performed.
 916                                  *
 917                                  * Consider ctx1..3, vif1..6, each ctx has 2
 918                                  * vifs. vif1 and vif2 from ctx1 request new
 919                                  * different chandefs starting 2 in-place
 920                                  * reserations with ctx4 and ctx5 replacing
 921                                  * ctx1 and ctx2 respectively. Next vif5 and
 922                                  * vif6 from ctx3 reserve ctx4. If vif3 and
 923                                  * vif4 remain on ctx2 as they are then this
 924                                  * fails unless `replace_ctx` from ctx5 is
 925                                  * replaced with ctx3.
 926                                  */
 927                                 list_for_each_entry(ctx, &local->chanctx_list,
 928                                                     list) {
 929                                         if (ctx->replace_state !=
 930                                             IEEE80211_CHANCTX_REPLACE_NONE)
 931                                                 continue;
 932
 933                                         if (!list_empty(&ctx->reserved_vifs))
 934                                                 continue;
 935
 936                                         curr_ctx = ctx;
 937                                         break;
 938                                 }
 939                         }
 940
 941                         /*
 942                          * If that's true then all available contexts already
 943                          * have reservations and cannot be used.
 944                          */
 945                         if (!curr_ctx ||
 946                             (curr_ctx->replace_state ==
 947                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 948                             !list_empty(&curr_ctx->reserved_vifs))
 949                                 return -EBUSY;
 950
 951                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 952                         if (!new_ctx)
 953                                 return -ENOMEM;
 954
 955                         new_ctx->replace_ctx = curr_ctx;
 956                         new_ctx->replace_state =
 957                                         IEEE80211_CHANCTX_REPLACES_OTHER;
 958
 959                         curr_ctx->replace_ctx = new_ctx;
 960                         curr_ctx->replace_state =
 961                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
 962
 963                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
 964                 }
 965         }
 966
 967         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
 968         sdata->reserved_chanctx = new_ctx;
 969         sdata->reserved_chandef = *chandef;
 970         sdata->reserved_radar_required = radar_required;
 971         sdata->reserved_ready = false;
 972
 973         return 0;
 974 }
 975
 976 static void
 977 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
 978 {
 979         switch (sdata->vif.type) {
 980         case NL80211_IFTYPE_ADHOC:
 981         case NL80211_IFTYPE_AP:
 982         case NL80211_IFTYPE_MESH_POINT:
 983         case NL80211_IFTYPE_OCB:
 984                 ieee80211_queue_work(&sdata->local->hw,
 985                                      &sdata->csa_finalize_work);
 986                 break;
 987         case NL80211_IFTYPE_STATION:
 988                 ieee80211_queue_work(&sdata->local->hw,
 989                                      &sdata->u.mgd.chswitch_work);
 990                 break;
 991         case NL80211_IFTYPE_UNSPECIFIED:
 992         case NL80211_IFTYPE_AP_VLAN:
 993         case NL80211_IFTYPE_WDS:
 994         case NL80211_IFTYPE_MONITOR:
 995         case NL80211_IFTYPE_P2P_CLIENT:
 996         case NL80211_IFTYPE_P2P_GO:
 997         case NL80211_IFTYPE_P2P_DEVICE:
 998         case NL80211_IFTYPE_NAN:
 999         case NUM_NL80211_IFTYPES:
1000                 WARN_ON(1);
1001                 break;
1002         }
1003 }
1004
1005 static void
1006 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
1007                              const struct cfg80211_chan_def *chandef)
1008 {
1009         struct ieee80211_sub_if_data *vlan;
1010
1011         sdata->vif.bss_conf.chandef = *chandef;
1012
1013         if (sdata->vif.type != NL80211_IFTYPE_AP)
1014                 return;
1015
1016         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1017                 vlan->vif.bss_conf.chandef = *chandef;
1018 }
1019
1020 static int
1021 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
1022 {
1023         struct ieee80211_local *local = sdata->local;
1024         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1025         struct ieee80211_chanctx *old_ctx, *new_ctx;
1026         const struct cfg80211_chan_def *chandef;
1027         u32 changed = 0;
1028         int err;
1029
1030         lockdep_assert_held(&local->mtx);
1031         lockdep_assert_held(&local->chanctx_mtx);
1032
1033         new_ctx = sdata->reserved_chanctx;
1034         old_ctx = ieee80211_vif_get_chanctx(sdata);
1035
1036         if (WARN_ON(!sdata->reserved_ready))
1037                 return -EBUSY;
1038
1039         if (WARN_ON(!new_ctx))
1040                 return -EINVAL;
1041
1042         if (WARN_ON(!old_ctx))
1043                 return -EINVAL;
1044
1045         if (WARN_ON(new_ctx->replace_state ==
1046                     IEEE80211_CHANCTX_REPLACES_OTHER))
1047                 return -EINVAL;
1048
1049         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1050                                 &sdata->reserved_chandef);
1051         if (WARN_ON(!chandef))
1052                 return -EINVAL;
1053
1054         ieee80211_change_chanctx(local, new_ctx, chandef);
1055
1056         vif_chsw[0].vif = &sdata->vif;
1057         vif_chsw[0].old_ctx = &old_ctx->conf;
1058         vif_chsw[0].new_ctx = &new_ctx->conf;
1059
1060         list_del(&sdata->reserved_chanctx_list);
1061         sdata->reserved_chanctx = NULL;
1062
1063         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1064                                      CHANCTX_SWMODE_REASSIGN_VIF);
1065         if (err) {
1066                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1067                         ieee80211_free_chanctx(local, new_ctx);
1068
1069                 goto out;
1070         }
1071
1072         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1073         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1074
1075         if (sdata->vif.type == NL80211_IFTYPE_AP)
1076                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1077
1078         ieee80211_check_fast_xmit_iface(sdata);
1079
1080         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1081                 ieee80211_free_chanctx(local, old_ctx);
1082
1083         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1084                 changed = BSS_CHANGED_BANDWIDTH;
1085
1086         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1087
1088         ieee80211_recalc_smps_chanctx(local, new_ctx);
1089         ieee80211_recalc_radar_chanctx(local, new_ctx);
1090         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1091
1092         if (changed)
1093                 ieee80211_bss_info_change_notify(sdata, changed);
1094
1095 out:
1096         ieee80211_vif_chanctx_reservation_complete(sdata);
1097         return err;
1098 }
1099
1100 static int
1101 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1102 {
1103         struct ieee80211_local *local = sdata->local;
1104         struct ieee80211_chanctx *old_ctx, *new_ctx;
1105         const struct cfg80211_chan_def *chandef;
1106         int err;
1107
1108         old_ctx = ieee80211_vif_get_chanctx(sdata);
1109         new_ctx = sdata->reserved_chanctx;
1110
1111         if (WARN_ON(!sdata->reserved_ready))
1112                 return -EINVAL;
1113
1114         if (WARN_ON(old_ctx))
1115                 return -EINVAL;
1116
1117         if (WARN_ON(!new_ctx))
1118                 return -EINVAL;
1119
1120         if (WARN_ON(new_ctx->replace_state ==
1121                     IEEE80211_CHANCTX_REPLACES_OTHER))
1122                 return -EINVAL;
1123
1124         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1125                                 &sdata->reserved_chandef);
1126         if (WARN_ON(!chandef))
1127                 return -EINVAL;
1128
1129         ieee80211_change_chanctx(local, new_ctx, chandef);
1130
1131         list_del(&sdata->reserved_chanctx_list);
1132         sdata->reserved_chanctx = NULL;
1133
1134         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1135         if (err) {
1136                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1137                         ieee80211_free_chanctx(local, new_ctx);
1138
1139                 goto out;
1140         }
1141
1142 out:
1143         ieee80211_vif_chanctx_reservation_complete(sdata);
1144         return err;
1145 }
1146
1147 static bool
1148 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1149 {
1150         struct ieee80211_chanctx *old_ctx, *new_ctx;
1151
1152         lockdep_assert_held(&sdata->local->chanctx_mtx);
1153
1154         new_ctx = sdata->reserved_chanctx;
1155         old_ctx = ieee80211_vif_get_chanctx(sdata);
1156
1157         if (!old_ctx)
1158                 return false;
1159
1160         if (WARN_ON(!new_ctx))
1161                 return false;
1162
1163         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1164                 return false;
1165
1166         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1167                 return false;
1168
1169         return true;
1170 }
1171
1172 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1173                                         struct ieee80211_chanctx *new_ctx)
1174 {
1175         const struct cfg80211_chan_def *chandef;
1176
1177         lockdep_assert_held(&local->mtx);
1178         lockdep_assert_held(&local->chanctx_mtx);
1179
1180         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1181         if (WARN_ON(!chandef))
1182                 return -EINVAL;
1183
1184         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1185         local->_oper_chandef = *chandef;
1186         ieee80211_hw_config(local, 0);
1187
1188         return 0;
1189 }
1190
1191 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1192                                       int n_vifs)
1193 {
1194         struct ieee80211_vif_chanctx_switch *vif_chsw;
1195         struct ieee80211_sub_if_data *sdata;
1196         struct ieee80211_chanctx *ctx, *old_ctx;
1197         int i, err;
1198
1199         lockdep_assert_held(&local->mtx);
1200         lockdep_assert_held(&local->chanctx_mtx);
1201
1202         vif_chsw = kcalloc(n_vifs, sizeof(vif_chsw[0]), GFP_KERNEL);
1203         if (!vif_chsw)
1204                 return -ENOMEM;
1205
1206         i = 0;
1207         list_for_each_entry(ctx, &local->chanctx_list, list) {
1208                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1209                         continue;
1210
1211                 if (WARN_ON(!ctx->replace_ctx)) {
1212                         err = -EINVAL;
1213                         goto out;
1214                 }
1215
1216                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1217                                     reserved_chanctx_list) {
1218                         if (!ieee80211_vif_has_in_place_reservation(
1219                                         sdata))
1220                                 continue;
1221
1222                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1223                         vif_chsw[i].vif = &sdata->vif;
1224                         vif_chsw[i].old_ctx = &old_ctx->conf;
1225                         vif_chsw[i].new_ctx = &ctx->conf;
1226
1227                         i++;
1228                 }
1229         }
1230
1231         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1232                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1233
1234 out:
1235         kfree(vif_chsw);
1236         return err;
1237 }
1238
1239 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1240 {
1241         struct ieee80211_chanctx *ctx;
1242         int err;
1243
1244         lockdep_assert_held(&local->mtx);
1245         lockdep_assert_held(&local->chanctx_mtx);
1246
1247         list_for_each_entry(ctx, &local->chanctx_list, list) {
1248                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1249                         continue;
1250
1251                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1252                         continue;
1253
1254                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1255                 err = ieee80211_add_chanctx(local, ctx);
1256                 if (err)
1257                         goto err;
1258         }
1259
1260         return 0;
1261
1262 err:
1263         WARN_ON(ieee80211_add_chanctx(local, ctx));
1264         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1265                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1266                         continue;
1267
1268                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1269                         continue;
1270
1271                 ieee80211_del_chanctx(local, ctx);
1272                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1273         }
1274
1275         return err;
1276 }
1277
1278 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1279 {
1280         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1281         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1282         struct ieee80211_chanctx *new_ctx = NULL;
1283         int err, n_assigned, n_reserved, n_ready;
1284         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1285
1286         lockdep_assert_held(&local->mtx);
1287         lockdep_assert_held(&local->chanctx_mtx);
1288
1289         /*
1290          * If there are 2 independent pairs of channel contexts performing
1291          * cross-switch of their vifs this code will still wait until both are
1292          * ready even though it could be possible to switch one before the
1293          * other is ready.
1294          *
1295          * For practical reasons and code simplicity just do a single huge
1296          * switch.
1297          */
1298
1299         /*
1300          * Verify if the reservation is still feasible.
1301          *  - if it's not then disconnect
1302          *  - if it is but not all vifs necessary are ready then defer
1303          */
1304
1305         list_for_each_entry(ctx, &local->chanctx_list, list) {
1306                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1307                         continue;
1308
1309                 if (WARN_ON(!ctx->replace_ctx)) {
1310                         err = -EINVAL;
1311                         goto err;
1312                 }
1313
1314                 if (!local->use_chanctx)
1315                         new_ctx = ctx;
1316
1317                 n_ctx++;
1318
1319                 n_assigned = 0;
1320                 n_reserved = 0;
1321                 n_ready = 0;
1322
1323                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1324                                     assigned_chanctx_list) {
1325                         n_assigned++;
1326                         if (sdata->reserved_chanctx) {
1327                                 n_reserved++;
1328                                 if (sdata->reserved_ready)
1329                                         n_ready++;
1330                         }
1331                 }
1332
1333                 if (n_assigned != n_reserved) {
1334                         if (n_ready == n_reserved) {
1335                                 wiphy_info(local->hw.wiphy,
1336                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1337                                 err = -EBUSY;
1338                                 goto err;
1339                         }
1340
1341                         return -EAGAIN;
1342                 }
1343
1344                 ctx->conf.radar_enabled = false;
1345                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1346                                     reserved_chanctx_list) {
1347                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1348                             !sdata->reserved_ready)
1349                                 return -EAGAIN;
1350
1351                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1352                         if (old_ctx) {
1353                                 if (old_ctx->replace_state ==
1354                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1355                                         n_vifs_switch++;
1356                                 else
1357                                         n_vifs_assign++;
1358                         } else {
1359                                 n_vifs_ctxless++;
1360                         }
1361
1362                         if (sdata->reserved_radar_required)
1363                                 ctx->conf.radar_enabled = true;
1364                 }
1365         }
1366
1367         if (WARN_ON(n_ctx == 0) ||
1368             WARN_ON(n_vifs_switch == 0 &&
1369                     n_vifs_assign == 0 &&
1370                     n_vifs_ctxless == 0) ||
1371             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1372             WARN_ON(!new_ctx && !local->use_chanctx)) {
1373                 err = -EINVAL;
1374                 goto err;
1375         }
1376
1377         /*
1378          * All necessary vifs are ready. Perform the switch now depending on
1379          * reservations and driver capabilities.
1380          */
1381
1382         if (local->use_chanctx) {
1383                 if (n_vifs_switch > 0) {
1384                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1385                         if (err)
1386                                 goto err;
1387                 }
1388
1389                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1390                         err = ieee80211_chsw_switch_ctxs(local);
1391                         if (err)
1392                                 goto err;
1393                 }
1394         } else {
1395                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1396                 if (err)
1397                         goto err;
1398         }
1399
1400         /*
1401          * Update all structures, values and pointers to point to new channel
1402          * context(s).
1403          */
1404         list_for_each_entry(ctx, &local->chanctx_list, list) {
1405                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1406                         continue;
1407
1408                 if (WARN_ON(!ctx->replace_ctx)) {
1409                         err = -EINVAL;
1410                         goto err;
1411                 }
1412
1413                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1414                                     reserved_chanctx_list) {
1415                         u32 changed = 0;
1416
1417                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1418                                 continue;
1419
1420                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1421
1422                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1423                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1424                                                                       false);
1425
1426                         ieee80211_check_fast_xmit_iface(sdata);
1427
1428                         sdata->radar_required = sdata->reserved_radar_required;
1429
1430                         if (sdata->vif.bss_conf.chandef.width !=
1431                             sdata->reserved_chandef.width)
1432                                 changed = BSS_CHANGED_BANDWIDTH;
1433
1434                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1435                         if (changed)
1436                                 ieee80211_bss_info_change_notify(sdata,
1437                                                                  changed);
1438
1439                         ieee80211_recalc_txpower(sdata, false);
1440                 }
1441
1442                 ieee80211_recalc_chanctx_chantype(local, ctx);
1443                 ieee80211_recalc_smps_chanctx(local, ctx);
1444                 ieee80211_recalc_radar_chanctx(local, ctx);
1445                 ieee80211_recalc_chanctx_min_def(local, ctx);
1446
1447                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1448                                          reserved_chanctx_list) {
1449                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1450                                 continue;
1451
1452                         list_del(&sdata->reserved_chanctx_list);
1453                         list_move(&sdata->assigned_chanctx_list,
1454                                   &ctx->assigned_vifs);
1455                         sdata->reserved_chanctx = NULL;
1456
1457                         ieee80211_vif_chanctx_reservation_complete(sdata);
1458                 }
1459
1460                 /*
1461                  * This context might have been a dependency for an already
1462                  * ready re-assign reservation interface that was deferred. Do
1463                  * not propagate error to the caller though. The in-place
1464                  * reservation for originally requested interface has already
1465                  * succeeded at this point.
1466                  */
1467                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1468                                          reserved_chanctx_list) {
1469                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1470                                         sdata)))
1471                                 continue;
1472
1473                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1474                                 continue;
1475
1476                         if (!sdata->reserved_ready)
1477                                 continue;
1478
1479                         if (ieee80211_vif_get_chanctx(sdata))
1480                                 err = ieee80211_vif_use_reserved_reassign(
1481                                                 sdata);
1482                         else
1483                                 err = ieee80211_vif_use_reserved_assign(sdata);
1484
1485                         if (err) {
1486                                 sdata_info(sdata,
1487                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1488                                            err);
1489                                 ieee80211_vif_unreserve_chanctx(sdata);
1490                                 cfg80211_stop_iface(local->hw.wiphy,
1491                                                     &sdata->wdev,
1492                                                     GFP_KERNEL);
1493                         }
1494                 }
1495         }
1496
1497         /*
1498          * Finally free old contexts
1499          */
1500
1501         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1502                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1503                         continue;
1504
1505                 ctx->replace_ctx->replace_ctx = NULL;
1506                 ctx->replace_ctx->replace_state =
1507                                 IEEE80211_CHANCTX_REPLACE_NONE;
1508
1509                 list_del_rcu(&ctx->list);
1510                 kfree_rcu(ctx, rcu_head);
1511         }
1512
1513         return 0;
1514
1515 err:
1516         list_for_each_entry(ctx, &local->chanctx_list, list) {
1517                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1518                         continue;
1519
1520                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1521                                          reserved_chanctx_list) {
1522                         ieee80211_vif_unreserve_chanctx(sdata);
1523                         ieee80211_vif_chanctx_reservation_complete(sdata);
1524                 }
1525         }
1526
1527         return err;
1528 }
1529
1530 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1531 {
1532         struct ieee80211_local *local = sdata->local;
1533         struct ieee80211_chanctx_conf *conf;
1534         struct ieee80211_chanctx *ctx;
1535         bool use_reserved_switch = false;
1536
1537         lockdep_assert_held(&local->chanctx_mtx);
1538
1539         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1540                                          lockdep_is_held(&local->chanctx_mtx));
1541         if (!conf)
1542                 return;
1543
1544         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1545
1546         if (sdata->reserved_chanctx) {
1547                 if (sdata->reserved_chanctx->replace_state ==
1548                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1549                     ieee80211_chanctx_num_reserved(local,
1550                                                    sdata->reserved_chanctx) > 1)
1551                         use_reserved_switch = true;
1552
1553                 ieee80211_vif_unreserve_chanctx(sdata);
1554         }
1555
1556         ieee80211_assign_vif_chanctx(sdata, NULL);
1557         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1558                 ieee80211_free_chanctx(local, ctx);
1559
1560         sdata->radar_required = false;
1561
1562         /* Unreserving may ready an in-place reservation. */
1563         if (use_reserved_switch)
1564                 ieee80211_vif_use_reserved_switch(local);
1565 }
1566
1567 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1568                               const struct cfg80211_chan_def *chandef,
1569                               enum ieee80211_chanctx_mode mode)
1570 {
1571         struct ieee80211_local *local = sdata->local;
1572         struct ieee80211_chanctx *ctx;
1573         u8 radar_detect_width = 0;
1574         int ret;
1575
1576         lockdep_assert_held(&local->mtx);
1577
1578         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1579
1580         mutex_lock(&local->chanctx_mtx);
1581
1582         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1583                                             chandef,
1584                                             sdata->wdev.iftype);
1585         if (ret < 0)
1586                 goto out;
1587         if (ret > 0)
1588                 radar_detect_width = BIT(chandef->width);
1589
1590         sdata->radar_required = ret;
1591
1592         ret = ieee80211_check_combinations(sdata, chandef, mode,
1593                                            radar_detect_width);
1594         if (ret < 0)
1595                 goto out;
1596
1597         __ieee80211_vif_release_channel(sdata);
1598
1599         ctx = ieee80211_find_chanctx(local, chandef, mode);
1600         if (!ctx)
1601                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1602         if (IS_ERR(ctx)) {
1603                 ret = PTR_ERR(ctx);
1604                 goto out;
1605         }
1606
1607         ieee80211_vif_update_chandef(sdata, chandef);
1608
1609         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1610         if (ret) {
1611                 /* if assign fails refcount stays the same */
1612                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1613                         ieee80211_free_chanctx(local, ctx);
1614                 goto out;
1615         }
1616
1617         ieee80211_recalc_smps_chanctx(local, ctx);
1618         ieee80211_recalc_radar_chanctx(local, ctx);
1619  out:
1620         if (ret)
1621                 sdata->radar_required = false;
1622
1623         mutex_unlock(&local->chanctx_mtx);
1624         return ret;
1625 }
1626
1627 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1628 {
1629         struct ieee80211_local *local = sdata->local;
1630         struct ieee80211_chanctx *new_ctx;
1631         struct ieee80211_chanctx *old_ctx;
1632         int err;
1633
1634         lockdep_assert_held(&local->mtx);
1635         lockdep_assert_held(&local->chanctx_mtx);
1636
1637         new_ctx = sdata->reserved_chanctx;
1638         old_ctx = ieee80211_vif_get_chanctx(sdata);
1639
1640         if (WARN_ON(!new_ctx))
1641                 return -EINVAL;
1642
1643         if (WARN_ON(new_ctx->replace_state ==
1644                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1645                 return -EINVAL;
1646
1647         if (WARN_ON(sdata->reserved_ready))
1648                 return -EINVAL;
1649
1650         sdata->reserved_ready = true;
1651
1652         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1653                 if (old_ctx)
1654                         err = ieee80211_vif_use_reserved_reassign(sdata);
1655                 else
1656                         err = ieee80211_vif_use_reserved_assign(sdata);
1657
1658                 if (err)
1659                         return err;
1660         }
1661
1662         /*
1663          * In-place reservation may need to be finalized now either if:
1664          *  a) sdata is taking part in the swapping itself and is the last one
1665          *  b) sdata has switched with a re-assign reservation to an existing
1666          *     context readying in-place switching of old_ctx
1667          *
1668          * In case of (b) do not propagate the error up because the requested
1669          * sdata already switched successfully. Just spill an extra warning.
1670          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1671          * interfaces upon failure.
1672          */
1673         if ((old_ctx &&
1674              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1675             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1676                 err = ieee80211_vif_use_reserved_switch(local);
1677                 if (err && err != -EAGAIN) {
1678                         if (new_ctx->replace_state ==
1679                             IEEE80211_CHANCTX_REPLACES_OTHER)
1680                                 return err;
1681
1682                         wiphy_info(local->hw.wiphy,
1683                                    "depending in-place reservation failed (err=%d)\n",
1684                                    err);
1685                 }
1686         }
1687
1688         return 0;
1689 }
1690
1691 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1692                                    const struct cfg80211_chan_def *chandef,
1693                                    u32 *changed)
1694 {
1695         struct ieee80211_local *local = sdata->local;
1696         struct ieee80211_chanctx_conf *conf;
1697         struct ieee80211_chanctx *ctx;
1698         const struct cfg80211_chan_def *compat;
1699         int ret;
1700
1701         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1702                                      IEEE80211_CHAN_DISABLED))
1703                 return -EINVAL;
1704
1705         mutex_lock(&local->chanctx_mtx);
1706         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1707                 ret = 0;
1708                 goto out;
1709         }
1710
1711         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1712             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1713                 ret = -EINVAL;
1714                 goto out;
1715         }
1716
1717         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1718                                          lockdep_is_held(&local->chanctx_mtx));
1719         if (!conf) {
1720                 ret = -EINVAL;
1721                 goto out;
1722         }
1723
1724         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1725
1726         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1727         if (!compat) {
1728                 ret = -EINVAL;
1729                 goto out;
1730         }
1731
1732         switch (ctx->replace_state) {
1733         case IEEE80211_CHANCTX_REPLACE_NONE:
1734                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1735                         ret = -EBUSY;
1736                         goto out;
1737                 }
1738                 break;
1739         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1740                 /* TODO: Perhaps the bandwidth change could be treated as a
1741                  * reservation itself? */
1742                 ret = -EBUSY;
1743                 goto out;
1744         case IEEE80211_CHANCTX_REPLACES_OTHER:
1745                 /* channel context that is going to replace another channel
1746                  * context doesn't really exist and shouldn't be assigned
1747                  * anywhere yet */
1748                 WARN_ON(1);
1749                 break;
1750         }
1751
1752         ieee80211_vif_update_chandef(sdata, chandef);
1753
1754         ieee80211_recalc_chanctx_chantype(local, ctx);
1755
1756         *changed |= BSS_CHANGED_BANDWIDTH;
1757         ret = 0;
1758  out:
1759         mutex_unlock(&local->chanctx_mtx);
1760         return ret;
1761 }
1762
1763 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1764 {
1765         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1766
1767         lockdep_assert_held(&sdata->local->mtx);
1768
1769         mutex_lock(&sdata->local->chanctx_mtx);
1770         __ieee80211_vif_release_channel(sdata);
1771         mutex_unlock(&sdata->local->chanctx_mtx);
1772 }
1773
1774 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1775 {
1776         struct ieee80211_local *local = sdata->local;
1777         struct ieee80211_sub_if_data *ap;
1778         struct ieee80211_chanctx_conf *conf;
1779
1780         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1781                 return;
1782
1783         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1784
1785         mutex_lock(&local->chanctx_mtx);
1786
1787         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1788                                          lockdep_is_held(&local->chanctx_mtx));
1789         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1790         mutex_unlock(&local->chanctx_mtx);
1791 }
1792
1793 void ieee80211_iter_chan_contexts_atomic(
1794         struct ieee80211_hw *hw,
1795         void (*iter)(struct ieee80211_hw *hw,
1796                      struct ieee80211_chanctx_conf *chanctx_conf,
1797                      void *data),
1798         void *iter_data)
1799 {
1800         struct ieee80211_local *local = hw_to_local(hw);
1801         struct ieee80211_chanctx *ctx;
1802
1803         rcu_read_lock();
1804         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1805                 if (ctx->driver_present)
1806                         iter(hw, &ctx->conf, iter_data);
1807         rcu_read_unlock();
1808 }
1809 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);