net/mac80211/chan.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * mac80211 - channel management
   4  */
   5
   6 #include <linux/nl80211.h>
   7 #include <linux/export.h>
   8 #include <linux/rtnetlink.h>
   9 #include <net/cfg80211.h>
  10 #include "ieee80211_i.h"
  11 #include "driver-ops.h"
  12
  13 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
  14                                           struct ieee80211_chanctx *ctx)
  15 {
  16         struct ieee80211_sub_if_data *sdata;
  17         int num = 0;
  18
  19         lockdep_assert_held(&local->chanctx_mtx);
  20
  21         list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
  22                 num++;
  23
  24         return num;
  25 }
  26
  27 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
  28                                           struct ieee80211_chanctx *ctx)
  29 {
  30         struct ieee80211_sub_if_data *sdata;
  31         int num = 0;
  32
  33         lockdep_assert_held(&local->chanctx_mtx);
  34
  35         list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
  36                 num++;
  37
  38         return num;
  39 }
  40
  41 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
  42                                struct ieee80211_chanctx *ctx)
  43 {
  44         return ieee80211_chanctx_num_assigned(local, ctx) +
  45                ieee80211_chanctx_num_reserved(local, ctx);
  46 }
  47
  48 static int ieee80211_num_chanctx(struct ieee80211_local *local)
  49 {
  50         struct ieee80211_chanctx *ctx;
  51         int num = 0;
  52
  53         lockdep_assert_held(&local->chanctx_mtx);
  54
  55         list_for_each_entry(ctx, &local->chanctx_list, list)
  56                 num++;
  57
  58         return num;
  59 }
  60
  61 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
  62 {
  63         lockdep_assert_held(&local->chanctx_mtx);
  64         return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
  65 }
  66
  67 static struct ieee80211_chanctx *
  68 ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
  69 {
  70         struct ieee80211_local *local __maybe_unused = sdata->local;
  71         struct ieee80211_chanctx_conf *conf;
  72
  73         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
  74                                          lockdep_is_held(&local->chanctx_mtx));
  75         if (!conf)
  76                 return NULL;
  77
  78         return container_of(conf, struct ieee80211_chanctx, conf);
  79 }
  80
  81 static const struct cfg80211_chan_def *
  82 ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
  83                                    struct ieee80211_chanctx *ctx,
  84                                    const struct cfg80211_chan_def *compat)
  85 {
  86         struct ieee80211_sub_if_data *sdata;
  87
  88         lockdep_assert_held(&local->chanctx_mtx);
  89
  90         list_for_each_entry(sdata, &ctx->reserved_vifs,
  91                             reserved_chanctx_list) {
  92                 if (!compat)
  93                         compat = &sdata->reserved_chandef;
  94
  95                 compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
  96                                                      compat);
  97                 if (!compat)
  98                         break;
  99         }
 100
 101         return compat;
 102 }
 103
 104 static const struct cfg80211_chan_def *
 105 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
 106                                        struct ieee80211_chanctx *ctx,
 107                                        const struct cfg80211_chan_def *compat)
 108 {
 109         struct ieee80211_sub_if_data *sdata;
 110
 111         lockdep_assert_held(&local->chanctx_mtx);
 112
 113         list_for_each_entry(sdata, &ctx->assigned_vifs,
 114                             assigned_chanctx_list) {
 115                 if (sdata->reserved_chanctx != NULL)
 116                         continue;
 117
 118                 if (!compat)
 119                         compat = &sdata->vif.bss_conf.chandef;
 120
 121                 compat = cfg80211_chandef_compatible(
 122                                 &sdata->vif.bss_conf.chandef, compat);
 123                 if (!compat)
 124                         break;
 125         }
 126
 127         return compat;
 128 }
 129
 130 static const struct cfg80211_chan_def *
 131 ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
 132                                    struct ieee80211_chanctx *ctx,
 133                                    const struct cfg80211_chan_def *compat)
 134 {
 135         lockdep_assert_held(&local->chanctx_mtx);
 136
 137         compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
 138         if (!compat)
 139                 return NULL;
 140
 141         compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
 142         if (!compat)
 143                 return NULL;
 144
 145         return compat;
 146 }
 147
 148 static bool
 149 ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
 150                                       struct ieee80211_chanctx *ctx,
 151                                       const struct cfg80211_chan_def *def)
 152 {
 153         lockdep_assert_held(&local->chanctx_mtx);
 154
 155         if (ieee80211_chanctx_combined_chandef(local, ctx, def))
 156                 return true;
 157
 158         if (!list_empty(&ctx->reserved_vifs) &&
 159             ieee80211_chanctx_reserved_chandef(local, ctx, def))
 160                 return true;
 161
 162         return false;
 163 }
 164
 165 static struct ieee80211_chanctx *
 166 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
 167                                    const struct cfg80211_chan_def *chandef,
 168                                    enum ieee80211_chanctx_mode mode)
 169 {
 170         struct ieee80211_chanctx *ctx;
 171
 172         lockdep_assert_held(&local->chanctx_mtx);
 173
 174         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 175                 return NULL;
 176
 177         list_for_each_entry(ctx, &local->chanctx_list, list) {
 178                 if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
 179                         continue;
 180
 181                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 182                         continue;
 183
 184                 if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
 185                                                            chandef))
 186                         continue;
 187
 188                 return ctx;
 189         }
 190
 191         return NULL;
 192 }
 193
 194 enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
 195 {
 196         switch (sta->bandwidth) {
 197         case IEEE80211_STA_RX_BW_20:
 198                 if (sta->ht_cap.ht_supported)
 199                         return NL80211_CHAN_WIDTH_20;
 200                 else
 201                         return NL80211_CHAN_WIDTH_20_NOHT;
 202         case IEEE80211_STA_RX_BW_40:
 203                 return NL80211_CHAN_WIDTH_40;
 204         case IEEE80211_STA_RX_BW_80:
 205                 return NL80211_CHAN_WIDTH_80;
 206         case IEEE80211_STA_RX_BW_160:
 207                 /*
 208                  * This applied for both 160 and 80+80. since we use
 209                  * the returned value to consider degradation of
 210                  * ctx->conf.min_def, we have to make sure to take
 211                  * the bigger one (NL80211_CHAN_WIDTH_160).
 212                  * Otherwise we might try degrading even when not
 213                  * needed, as the max required sta_bw returned (80+80)
 214                  * might be smaller than the configured bw (160).
 215                  */
 216                 return NL80211_CHAN_WIDTH_160;
 217         default:
 218                 WARN_ON(1);
 219                 return NL80211_CHAN_WIDTH_20;
 220         }
 221 }
 222
 223 static enum nl80211_chan_width
 224 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
 225 {
 226         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 227         struct sta_info *sta;
 228
 229         rcu_read_lock();
 230         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
 231                 if (sdata != sta->sdata &&
 232                     !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
 233                         continue;
 234
 235                 max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
 236         }
 237         rcu_read_unlock();
 238
 239         return max_bw;
 240 }
 241
 242 static enum nl80211_chan_width
 243 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
 244                                       struct ieee80211_chanctx_conf *conf)
 245 {
 246         struct ieee80211_sub_if_data *sdata;
 247         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 248
 249         rcu_read_lock();
 250         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 251                 struct ieee80211_vif *vif = &sdata->vif;
 252                 enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
 253
 254                 if (!ieee80211_sdata_running(sdata))
 255                         continue;
 256
 257                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 258                         continue;
 259
 260                 switch (vif->type) {
 261                 case NL80211_IFTYPE_AP:
 262                 case NL80211_IFTYPE_AP_VLAN:
 263                         width = ieee80211_get_max_required_bw(sdata);
 264                         break;
 265                 case NL80211_IFTYPE_STATION:
 266                         /*
 267                          * The ap's sta->bandwidth is not set yet at this
 268                          * point, so take the width from the chandef, but
 269                          * account also for TDLS peers
 270                          */
 271                         width = max(vif->bss_conf.chandef.width,
 272                                     ieee80211_get_max_required_bw(sdata));
 273                         break;
 274                 case NL80211_IFTYPE_P2P_DEVICE:
 275                 case NL80211_IFTYPE_NAN:
 276                         continue;
 277                 case NL80211_IFTYPE_ADHOC:
 278                 case NL80211_IFTYPE_WDS:
 279                 case NL80211_IFTYPE_MESH_POINT:
 280                 case NL80211_IFTYPE_OCB:
 281                         width = vif->bss_conf.chandef.width;
 282                         break;
 283                 case NL80211_IFTYPE_UNSPECIFIED:
 284                 case NUM_NL80211_IFTYPES:
 285                 case NL80211_IFTYPE_MONITOR:
 286                 case NL80211_IFTYPE_P2P_CLIENT:
 287                 case NL80211_IFTYPE_P2P_GO:
 288                         WARN_ON_ONCE(1);
 289                 }
 290                 max_bw = max(max_bw, width);
 291         }
 292
 293         /* use the configured bandwidth in case of monitor interface */
 294         sdata = rcu_dereference(local->monitor_sdata);
 295         if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
 296                 max_bw = max(max_bw, conf->def.width);
 297
 298         rcu_read_unlock();
 299
 300         return max_bw;
 301 }
 302
 303 /*
 304  * recalc the min required chan width of the channel context, which is
 305  * the max of min required widths of all the interfaces bound to this
 306  * channel context.
 307  */
 308 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
 309                                       struct ieee80211_chanctx *ctx)
 310 {
 311         enum nl80211_chan_width max_bw;
 312         struct cfg80211_chan_def min_def;
 313
 314         lockdep_assert_held(&local->chanctx_mtx);
 315
 316         /* don't optimize 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_WDS:
 747                 case NL80211_IFTYPE_MESH_POINT:
 748                 case NL80211_IFTYPE_OCB:
 749                         break;
 750                 default:
 751                         WARN_ON_ONCE(1);
 752                 }
 753
 754                 switch (sdata->smps_mode) {
 755                 default:
 756                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
 757                                   sdata->smps_mode);
 758                         fallthrough;
 759                 case IEEE80211_SMPS_OFF:
 760                         needed_static = sdata->needed_rx_chains;
 761                         needed_dynamic = sdata->needed_rx_chains;
 762                         break;
 763                 case IEEE80211_SMPS_DYNAMIC:
 764                         needed_static = 1;
 765                         needed_dynamic = sdata->needed_rx_chains;
 766                         break;
 767                 case IEEE80211_SMPS_STATIC:
 768                         needed_static = 1;
 769                         needed_dynamic = 1;
 770                         break;
 771                 }
 772
 773                 rx_chains_static = max(rx_chains_static, needed_static);
 774                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
 775         }
 776
 777         /* Disable SMPS for the monitor interface */
 778         sdata = rcu_dereference(local->monitor_sdata);
 779         if (sdata &&
 780             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
 781                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
 782
 783         rcu_read_unlock();
 784
 785         if (!local->use_chanctx) {
 786                 if (rx_chains_static > 1)
 787                         local->smps_mode = IEEE80211_SMPS_OFF;
 788                 else if (rx_chains_dynamic > 1)
 789                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
 790                 else
 791                         local->smps_mode = IEEE80211_SMPS_STATIC;
 792                 ieee80211_hw_config(local, 0);
 793         }
 794
 795         if (rx_chains_static == chanctx->conf.rx_chains_static &&
 796             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
 797                 return;
 798
 799         chanctx->conf.rx_chains_static = rx_chains_static;
 800         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
 801         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
 802 }
 803
 804 static void
 805 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 806                                       bool clear)
 807 {
 808         struct ieee80211_local *local __maybe_unused = sdata->local;
 809         struct ieee80211_sub_if_data *vlan;
 810         struct ieee80211_chanctx_conf *conf;
 811
 812         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
 813                 return;
 814
 815         lockdep_assert_held(&local->mtx);
 816
 817         /* Check that conf exists, even when clearing this function
 818          * must be called with the AP's channel context still there
 819          * as it would otherwise cause VLANs to have an invalid
 820          * channel context pointer for a while, possibly pointing
 821          * to a channel context that has already been freed.
 822          */
 823         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 824                                          lockdep_is_held(&local->chanctx_mtx));
 825         WARN_ON(!conf);
 826
 827         if (clear)
 828                 conf = NULL;
 829
 830         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 831                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
 832 }
 833
 834 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 835                                          bool clear)
 836 {
 837         struct ieee80211_local *local = sdata->local;
 838
 839         mutex_lock(&local->chanctx_mtx);
 840
 841         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
 842
 843         mutex_unlock(&local->chanctx_mtx);
 844 }
 845
 846 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
 847 {
 848         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
 849
 850         lockdep_assert_held(&sdata->local->chanctx_mtx);
 851
 852         if (WARN_ON(!ctx))
 853                 return -EINVAL;
 854
 855         list_del(&sdata->reserved_chanctx_list);
 856         sdata->reserved_chanctx = NULL;
 857
 858         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
 859                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
 860                         if (WARN_ON(!ctx->replace_ctx))
 861                                 return -EINVAL;
 862
 863                         WARN_ON(ctx->replace_ctx->replace_state !=
 864                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
 865                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
 866
 867                         ctx->replace_ctx->replace_ctx = NULL;
 868                         ctx->replace_ctx->replace_state =
 869                                         IEEE80211_CHANCTX_REPLACE_NONE;
 870
 871                         list_del_rcu(&ctx->list);
 872                         kfree_rcu(ctx, rcu_head);
 873                 } else {
 874                         ieee80211_free_chanctx(sdata->local, ctx);
 875                 }
 876         }
 877
 878         return 0;
 879 }
 880
 881 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
 882                                   const struct cfg80211_chan_def *chandef,
 883                                   enum ieee80211_chanctx_mode mode,
 884                                   bool radar_required)
 885 {
 886         struct ieee80211_local *local = sdata->local;
 887         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
 888
 889         lockdep_assert_held(&local->chanctx_mtx);
 890
 891         curr_ctx = ieee80211_vif_get_chanctx(sdata);
 892         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
 893                 return -ENOTSUPP;
 894
 895         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
 896         if (!new_ctx) {
 897                 if (ieee80211_can_create_new_chanctx(local)) {
 898                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
 899                         if (IS_ERR(new_ctx))
 900                                 return PTR_ERR(new_ctx);
 901                 } else {
 902                         if (!curr_ctx ||
 903                             (curr_ctx->replace_state ==
 904                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 905                             !list_empty(&curr_ctx->reserved_vifs)) {
 906                                 /*
 907                                  * Another vif already requested this context
 908                                  * for a reservation. Find another one hoping
 909                                  * all vifs assigned to it will also switch
 910                                  * soon enough.
 911                                  *
 912                                  * TODO: This needs a little more work as some
 913                                  * cases (more than 2 chanctx capable devices)
 914                                  * may fail which could otherwise succeed
 915                                  * provided some channel context juggling was
 916                                  * performed.
 917                                  *
 918                                  * Consider ctx1..3, vif1..6, each ctx has 2
 919                                  * vifs. vif1 and vif2 from ctx1 request new
 920                                  * different chandefs starting 2 in-place
 921                                  * reserations with ctx4 and ctx5 replacing
 922                                  * ctx1 and ctx2 respectively. Next vif5 and
 923                                  * vif6 from ctx3 reserve ctx4. If vif3 and
 924                                  * vif4 remain on ctx2 as they are then this
 925                                  * fails unless `replace_ctx` from ctx5 is
 926                                  * replaced with ctx3.
 927                                  */
 928                                 list_for_each_entry(ctx, &local->chanctx_list,
 929                                                     list) {
 930                                         if (ctx->replace_state !=
 931                                             IEEE80211_CHANCTX_REPLACE_NONE)
 932                                                 continue;
 933
 934                                         if (!list_empty(&ctx->reserved_vifs))
 935                                                 continue;
 936
 937                                         curr_ctx = ctx;
 938                                         break;
 939                                 }
 940                         }
 941
 942                         /*
 943                          * If that's true then all available contexts already
 944                          * have reservations and cannot be used.
 945                          */
 946                         if (!curr_ctx ||
 947                             (curr_ctx->replace_state ==
 948                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 949                             !list_empty(&curr_ctx->reserved_vifs))
 950                                 return -EBUSY;
 951
 952                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 953                         if (!new_ctx)
 954                                 return -ENOMEM;
 955
 956                         new_ctx->replace_ctx = curr_ctx;
 957                         new_ctx->replace_state =
 958                                         IEEE80211_CHANCTX_REPLACES_OTHER;
 959
 960                         curr_ctx->replace_ctx = new_ctx;
 961                         curr_ctx->replace_state =
 962                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
 963
 964                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
 965                 }
 966         }
 967
 968         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
 969         sdata->reserved_chanctx = new_ctx;
 970         sdata->reserved_chandef = *chandef;
 971         sdata->reserved_radar_required = radar_required;
 972         sdata->reserved_ready = false;
 973
 974         return 0;
 975 }
 976
 977 static void
 978 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
 979 {
 980         switch (sdata->vif.type) {
 981         case NL80211_IFTYPE_ADHOC:
 982         case NL80211_IFTYPE_AP:
 983         case NL80211_IFTYPE_MESH_POINT:
 984         case NL80211_IFTYPE_OCB:
 985                 ieee80211_queue_work(&sdata->local->hw,
 986                                      &sdata->csa_finalize_work);
 987                 break;
 988         case NL80211_IFTYPE_STATION:
 989                 ieee80211_queue_work(&sdata->local->hw,
 990                                      &sdata->u.mgd.chswitch_work);
 991                 break;
 992         case NL80211_IFTYPE_UNSPECIFIED:
 993         case NL80211_IFTYPE_AP_VLAN:
 994         case NL80211_IFTYPE_WDS:
 995         case NL80211_IFTYPE_MONITOR:
 996         case NL80211_IFTYPE_P2P_CLIENT:
 997         case NL80211_IFTYPE_P2P_GO:
 998         case NL80211_IFTYPE_P2P_DEVICE:
 999         case NL80211_IFTYPE_NAN:
1000         case NUM_NL80211_IFTYPES:
1001                 WARN_ON(1);
1002                 break;
1003         }
1004 }
1005
1006 static void
1007 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
1008                              const struct cfg80211_chan_def *chandef)
1009 {
1010         struct ieee80211_sub_if_data *vlan;
1011
1012         sdata->vif.bss_conf.chandef = *chandef;
1013
1014         if (sdata->vif.type != NL80211_IFTYPE_AP)
1015                 return;
1016
1017         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1018                 vlan->vif.bss_conf.chandef = *chandef;
1019 }
1020
1021 static int
1022 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
1023 {
1024         struct ieee80211_local *local = sdata->local;
1025         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1026         struct ieee80211_chanctx *old_ctx, *new_ctx;
1027         const struct cfg80211_chan_def *chandef;
1028         u32 changed = 0;
1029         int err;
1030
1031         lockdep_assert_held(&local->mtx);
1032         lockdep_assert_held(&local->chanctx_mtx);
1033
1034         new_ctx = sdata->reserved_chanctx;
1035         old_ctx = ieee80211_vif_get_chanctx(sdata);
1036
1037         if (WARN_ON(!sdata->reserved_ready))
1038                 return -EBUSY;
1039
1040         if (WARN_ON(!new_ctx))
1041                 return -EINVAL;
1042
1043         if (WARN_ON(!old_ctx))
1044                 return -EINVAL;
1045
1046         if (WARN_ON(new_ctx->replace_state ==
1047                     IEEE80211_CHANCTX_REPLACES_OTHER))
1048                 return -EINVAL;
1049
1050         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1051                                 &sdata->reserved_chandef);
1052         if (WARN_ON(!chandef))
1053                 return -EINVAL;
1054
1055         ieee80211_change_chanctx(local, new_ctx, chandef);
1056
1057         vif_chsw[0].vif = &sdata->vif;
1058         vif_chsw[0].old_ctx = &old_ctx->conf;
1059         vif_chsw[0].new_ctx = &new_ctx->conf;
1060
1061         list_del(&sdata->reserved_chanctx_list);
1062         sdata->reserved_chanctx = NULL;
1063
1064         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1065                                      CHANCTX_SWMODE_REASSIGN_VIF);
1066         if (err) {
1067                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1068                         ieee80211_free_chanctx(local, new_ctx);
1069
1070                 goto out;
1071         }
1072
1073         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1074         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1075
1076         if (sdata->vif.type == NL80211_IFTYPE_AP)
1077                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1078
1079         ieee80211_check_fast_xmit_iface(sdata);
1080
1081         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1082                 ieee80211_free_chanctx(local, old_ctx);
1083
1084         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1085                 changed = BSS_CHANGED_BANDWIDTH;
1086
1087         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1088
1089         ieee80211_recalc_smps_chanctx(local, new_ctx);
1090         ieee80211_recalc_radar_chanctx(local, new_ctx);
1091         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1092
1093         if (changed)
1094                 ieee80211_bss_info_change_notify(sdata, changed);
1095
1096 out:
1097         ieee80211_vif_chanctx_reservation_complete(sdata);
1098         return err;
1099 }
1100
1101 static int
1102 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1103 {
1104         struct ieee80211_local *local = sdata->local;
1105         struct ieee80211_chanctx *old_ctx, *new_ctx;
1106         const struct cfg80211_chan_def *chandef;
1107         int err;
1108
1109         old_ctx = ieee80211_vif_get_chanctx(sdata);
1110         new_ctx = sdata->reserved_chanctx;
1111
1112         if (WARN_ON(!sdata->reserved_ready))
1113                 return -EINVAL;
1114
1115         if (WARN_ON(old_ctx))
1116                 return -EINVAL;
1117
1118         if (WARN_ON(!new_ctx))
1119                 return -EINVAL;
1120
1121         if (WARN_ON(new_ctx->replace_state ==
1122                     IEEE80211_CHANCTX_REPLACES_OTHER))
1123                 return -EINVAL;
1124
1125         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1126                                 &sdata->reserved_chandef);
1127         if (WARN_ON(!chandef))
1128                 return -EINVAL;
1129
1130         ieee80211_change_chanctx(local, new_ctx, chandef);
1131
1132         list_del(&sdata->reserved_chanctx_list);
1133         sdata->reserved_chanctx = NULL;
1134
1135         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1136         if (err) {
1137                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1138                         ieee80211_free_chanctx(local, new_ctx);
1139
1140                 goto out;
1141         }
1142
1143 out:
1144         ieee80211_vif_chanctx_reservation_complete(sdata);
1145         return err;
1146 }
1147
1148 static bool
1149 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1150 {
1151         struct ieee80211_chanctx *old_ctx, *new_ctx;
1152
1153         lockdep_assert_held(&sdata->local->chanctx_mtx);
1154
1155         new_ctx = sdata->reserved_chanctx;
1156         old_ctx = ieee80211_vif_get_chanctx(sdata);
1157
1158         if (!old_ctx)
1159                 return false;
1160
1161         if (WARN_ON(!new_ctx))
1162                 return false;
1163
1164         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1165                 return false;
1166
1167         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1168                 return false;
1169
1170         return true;
1171 }
1172
1173 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1174                                         struct ieee80211_chanctx *new_ctx)
1175 {
1176         const struct cfg80211_chan_def *chandef;
1177
1178         lockdep_assert_held(&local->mtx);
1179         lockdep_assert_held(&local->chanctx_mtx);
1180
1181         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1182         if (WARN_ON(!chandef))
1183                 return -EINVAL;
1184
1185         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1186         local->_oper_chandef = *chandef;
1187         ieee80211_hw_config(local, 0);
1188
1189         return 0;
1190 }
1191
1192 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1193                                       int n_vifs)
1194 {
1195         struct ieee80211_vif_chanctx_switch *vif_chsw;
1196         struct ieee80211_sub_if_data *sdata;
1197         struct ieee80211_chanctx *ctx, *old_ctx;
1198         int i, err;
1199
1200         lockdep_assert_held(&local->mtx);
1201         lockdep_assert_held(&local->chanctx_mtx);
1202
1203         vif_chsw = kcalloc(n_vifs, sizeof(vif_chsw[0]), GFP_KERNEL);
1204         if (!vif_chsw)
1205                 return -ENOMEM;
1206
1207         i = 0;
1208         list_for_each_entry(ctx, &local->chanctx_list, list) {
1209                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1210                         continue;
1211
1212                 if (WARN_ON(!ctx->replace_ctx)) {
1213                         err = -EINVAL;
1214                         goto out;
1215                 }
1216
1217                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1218                                     reserved_chanctx_list) {
1219                         if (!ieee80211_vif_has_in_place_reservation(
1220                                         sdata))
1221                                 continue;
1222
1223                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1224                         vif_chsw[i].vif = &sdata->vif;
1225                         vif_chsw[i].old_ctx = &old_ctx->conf;
1226                         vif_chsw[i].new_ctx = &ctx->conf;
1227
1228                         i++;
1229                 }
1230         }
1231
1232         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1233                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1234
1235 out:
1236         kfree(vif_chsw);
1237         return err;
1238 }
1239
1240 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1241 {
1242         struct ieee80211_chanctx *ctx;
1243         int err;
1244
1245         lockdep_assert_held(&local->mtx);
1246         lockdep_assert_held(&local->chanctx_mtx);
1247
1248         list_for_each_entry(ctx, &local->chanctx_list, list) {
1249                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1250                         continue;
1251
1252                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1253                         continue;
1254
1255                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1256                 err = ieee80211_add_chanctx(local, ctx);
1257                 if (err)
1258                         goto err;
1259         }
1260
1261         return 0;
1262
1263 err:
1264         WARN_ON(ieee80211_add_chanctx(local, ctx));
1265         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1266                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1267                         continue;
1268
1269                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1270                         continue;
1271
1272                 ieee80211_del_chanctx(local, ctx);
1273                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1274         }
1275
1276         return err;
1277 }
1278
1279 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1280 {
1281         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1282         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1283         struct ieee80211_chanctx *new_ctx = NULL;
1284         int err, n_assigned, n_reserved, n_ready;
1285         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1286
1287         lockdep_assert_held(&local->mtx);
1288         lockdep_assert_held(&local->chanctx_mtx);
1289
1290         /*
1291          * If there are 2 independent pairs of channel contexts performing
1292          * cross-switch of their vifs this code will still wait until both are
1293          * ready even though it could be possible to switch one before the
1294          * other is ready.
1295          *
1296          * For practical reasons and code simplicity just do a single huge
1297          * switch.
1298          */
1299
1300         /*
1301          * Verify if the reservation is still feasible.
1302          *  - if it's not then disconnect
1303          *  - if it is but not all vifs necessary are ready then defer
1304          */
1305
1306         list_for_each_entry(ctx, &local->chanctx_list, list) {
1307                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1308                         continue;
1309
1310                 if (WARN_ON(!ctx->replace_ctx)) {
1311                         err = -EINVAL;
1312                         goto err;
1313                 }
1314
1315                 if (!local->use_chanctx)
1316                         new_ctx = ctx;
1317
1318                 n_ctx++;
1319
1320                 n_assigned = 0;
1321                 n_reserved = 0;
1322                 n_ready = 0;
1323
1324                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1325                                     assigned_chanctx_list) {
1326                         n_assigned++;
1327                         if (sdata->reserved_chanctx) {
1328                                 n_reserved++;
1329                                 if (sdata->reserved_ready)
1330                                         n_ready++;
1331                         }
1332                 }
1333
1334                 if (n_assigned != n_reserved) {
1335                         if (n_ready == n_reserved) {
1336                                 wiphy_info(local->hw.wiphy,
1337                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1338                                 err = -EBUSY;
1339                                 goto err;
1340                         }
1341
1342                         return -EAGAIN;
1343                 }
1344
1345                 ctx->conf.radar_enabled = false;
1346                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1347                                     reserved_chanctx_list) {
1348                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1349                             !sdata->reserved_ready)
1350                                 return -EAGAIN;
1351
1352                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1353                         if (old_ctx) {
1354                                 if (old_ctx->replace_state ==
1355                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1356                                         n_vifs_switch++;
1357                                 else
1358                                         n_vifs_assign++;
1359                         } else {
1360                                 n_vifs_ctxless++;
1361                         }
1362
1363                         if (sdata->reserved_radar_required)
1364                                 ctx->conf.radar_enabled = true;
1365                 }
1366         }
1367
1368         if (WARN_ON(n_ctx == 0) ||
1369             WARN_ON(n_vifs_switch == 0 &&
1370                     n_vifs_assign == 0 &&
1371                     n_vifs_ctxless == 0) ||
1372             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1373             WARN_ON(!new_ctx && !local->use_chanctx)) {
1374                 err = -EINVAL;
1375                 goto err;
1376         }
1377
1378         /*
1379          * All necessary vifs are ready. Perform the switch now depending on
1380          * reservations and driver capabilities.
1381          */
1382
1383         if (local->use_chanctx) {
1384                 if (n_vifs_switch > 0) {
1385                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1386                         if (err)
1387                                 goto err;
1388                 }
1389
1390                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1391                         err = ieee80211_chsw_switch_ctxs(local);
1392                         if (err)
1393                                 goto err;
1394                 }
1395         } else {
1396                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1397                 if (err)
1398                         goto err;
1399         }
1400
1401         /*
1402          * Update all structures, values and pointers to point to new channel
1403          * context(s).
1404          */
1405         list_for_each_entry(ctx, &local->chanctx_list, list) {
1406                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1407                         continue;
1408
1409                 if (WARN_ON(!ctx->replace_ctx)) {
1410                         err = -EINVAL;
1411                         goto err;
1412                 }
1413
1414                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1415                                     reserved_chanctx_list) {
1416                         u32 changed = 0;
1417
1418                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1419                                 continue;
1420
1421                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1422
1423                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1424                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1425                                                                       false);
1426
1427                         ieee80211_check_fast_xmit_iface(sdata);
1428
1429                         sdata->radar_required = sdata->reserved_radar_required;
1430
1431                         if (sdata->vif.bss_conf.chandef.width !=
1432                             sdata->reserved_chandef.width)
1433                                 changed = BSS_CHANGED_BANDWIDTH;
1434
1435                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1436                         if (changed)
1437                                 ieee80211_bss_info_change_notify(sdata,
1438                                                                  changed);
1439
1440                         ieee80211_recalc_txpower(sdata, false);
1441                 }
1442
1443                 ieee80211_recalc_chanctx_chantype(local, ctx);
1444                 ieee80211_recalc_smps_chanctx(local, ctx);
1445                 ieee80211_recalc_radar_chanctx(local, ctx);
1446                 ieee80211_recalc_chanctx_min_def(local, ctx);
1447
1448                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1449                                          reserved_chanctx_list) {
1450                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1451                                 continue;
1452
1453                         list_del(&sdata->reserved_chanctx_list);
1454                         list_move(&sdata->assigned_chanctx_list,
1455                                   &ctx->assigned_vifs);
1456                         sdata->reserved_chanctx = NULL;
1457
1458                         ieee80211_vif_chanctx_reservation_complete(sdata);
1459                 }
1460
1461                 /*
1462                  * This context might have been a dependency for an already
1463                  * ready re-assign reservation interface that was deferred. Do
1464                  * not propagate error to the caller though. The in-place
1465                  * reservation for originally requested interface has already
1466                  * succeeded at this point.
1467                  */
1468                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1469                                          reserved_chanctx_list) {
1470                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1471                                         sdata)))
1472                                 continue;
1473
1474                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1475                                 continue;
1476
1477                         if (!sdata->reserved_ready)
1478                                 continue;
1479
1480                         if (ieee80211_vif_get_chanctx(sdata))
1481                                 err = ieee80211_vif_use_reserved_reassign(
1482                                                 sdata);
1483                         else
1484                                 err = ieee80211_vif_use_reserved_assign(sdata);
1485
1486                         if (err) {
1487                                 sdata_info(sdata,
1488                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1489                                            err);
1490                                 ieee80211_vif_unreserve_chanctx(sdata);
1491                                 cfg80211_stop_iface(local->hw.wiphy,
1492                                                     &sdata->wdev,
1493                                                     GFP_KERNEL);
1494                         }
1495                 }
1496         }
1497
1498         /*
1499          * Finally free old contexts
1500          */
1501
1502         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1503                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1504                         continue;
1505
1506                 ctx->replace_ctx->replace_ctx = NULL;
1507                 ctx->replace_ctx->replace_state =
1508                                 IEEE80211_CHANCTX_REPLACE_NONE;
1509
1510                 list_del_rcu(&ctx->list);
1511                 kfree_rcu(ctx, rcu_head);
1512         }
1513
1514         return 0;
1515
1516 err:
1517         list_for_each_entry(ctx, &local->chanctx_list, list) {
1518                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1519                         continue;
1520
1521                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1522                                          reserved_chanctx_list) {
1523                         ieee80211_vif_unreserve_chanctx(sdata);
1524                         ieee80211_vif_chanctx_reservation_complete(sdata);
1525                 }
1526         }
1527
1528         return err;
1529 }
1530
1531 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1532 {
1533         struct ieee80211_local *local = sdata->local;
1534         struct ieee80211_chanctx_conf *conf;
1535         struct ieee80211_chanctx *ctx;
1536         bool use_reserved_switch = false;
1537
1538         lockdep_assert_held(&local->chanctx_mtx);
1539
1540         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1541                                          lockdep_is_held(&local->chanctx_mtx));
1542         if (!conf)
1543                 return;
1544
1545         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1546
1547         if (sdata->reserved_chanctx) {
1548                 if (sdata->reserved_chanctx->replace_state ==
1549                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1550                     ieee80211_chanctx_num_reserved(local,
1551                                                    sdata->reserved_chanctx) > 1)
1552                         use_reserved_switch = true;
1553
1554                 ieee80211_vif_unreserve_chanctx(sdata);
1555         }
1556
1557         ieee80211_assign_vif_chanctx(sdata, NULL);
1558         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1559                 ieee80211_free_chanctx(local, ctx);
1560
1561         sdata->radar_required = false;
1562
1563         /* Unreserving may ready an in-place reservation. */
1564         if (use_reserved_switch)
1565                 ieee80211_vif_use_reserved_switch(local);
1566 }
1567
1568 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1569                               const struct cfg80211_chan_def *chandef,
1570                               enum ieee80211_chanctx_mode mode)
1571 {
1572         struct ieee80211_local *local = sdata->local;
1573         struct ieee80211_chanctx *ctx;
1574         u8 radar_detect_width = 0;
1575         int ret;
1576
1577         lockdep_assert_held(&local->mtx);
1578
1579         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1580
1581         mutex_lock(&local->chanctx_mtx);
1582
1583         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1584                                             chandef,
1585                                             sdata->wdev.iftype);
1586         if (ret < 0)
1587                 goto out;
1588         if (ret > 0)
1589                 radar_detect_width = BIT(chandef->width);
1590
1591         sdata->radar_required = ret;
1592
1593         ret = ieee80211_check_combinations(sdata, chandef, mode,
1594                                            radar_detect_width);
1595         if (ret < 0)
1596                 goto out;
1597
1598         __ieee80211_vif_release_channel(sdata);
1599
1600         ctx = ieee80211_find_chanctx(local, chandef, mode);
1601         if (!ctx)
1602                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1603         if (IS_ERR(ctx)) {
1604                 ret = PTR_ERR(ctx);
1605                 goto out;
1606         }
1607
1608         ieee80211_vif_update_chandef(sdata, chandef);
1609
1610         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1611         if (ret) {
1612                 /* if assign fails refcount stays the same */
1613                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1614                         ieee80211_free_chanctx(local, ctx);
1615                 goto out;
1616         }
1617
1618         ieee80211_recalc_smps_chanctx(local, ctx);
1619         ieee80211_recalc_radar_chanctx(local, ctx);
1620  out:
1621         if (ret)
1622                 sdata->radar_required = false;
1623
1624         mutex_unlock(&local->chanctx_mtx);
1625         return ret;
1626 }
1627
1628 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1629 {
1630         struct ieee80211_local *local = sdata->local;
1631         struct ieee80211_chanctx *new_ctx;
1632         struct ieee80211_chanctx *old_ctx;
1633         int err;
1634
1635         lockdep_assert_held(&local->mtx);
1636         lockdep_assert_held(&local->chanctx_mtx);
1637
1638         new_ctx = sdata->reserved_chanctx;
1639         old_ctx = ieee80211_vif_get_chanctx(sdata);
1640
1641         if (WARN_ON(!new_ctx))
1642                 return -EINVAL;
1643
1644         if (WARN_ON(new_ctx->replace_state ==
1645                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1646                 return -EINVAL;
1647
1648         if (WARN_ON(sdata->reserved_ready))
1649                 return -EINVAL;
1650
1651         sdata->reserved_ready = true;
1652
1653         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1654                 if (old_ctx)
1655                         err = ieee80211_vif_use_reserved_reassign(sdata);
1656                 else
1657                         err = ieee80211_vif_use_reserved_assign(sdata);
1658
1659                 if (err)
1660                         return err;
1661         }
1662
1663         /*
1664          * In-place reservation may need to be finalized now either if:
1665          *  a) sdata is taking part in the swapping itself and is the last one
1666          *  b) sdata has switched with a re-assign reservation to an existing
1667          *     context readying in-place switching of old_ctx
1668          *
1669          * In case of (b) do not propagate the error up because the requested
1670          * sdata already switched successfully. Just spill an extra warning.
1671          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1672          * interfaces upon failure.
1673          */
1674         if ((old_ctx &&
1675              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1676             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1677                 err = ieee80211_vif_use_reserved_switch(local);
1678                 if (err && err != -EAGAIN) {
1679                         if (new_ctx->replace_state ==
1680                             IEEE80211_CHANCTX_REPLACES_OTHER)
1681                                 return err;
1682
1683                         wiphy_info(local->hw.wiphy,
1684                                    "depending in-place reservation failed (err=%d)\n",
1685                                    err);
1686                 }
1687         }
1688
1689         return 0;
1690 }
1691
1692 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1693                                    const struct cfg80211_chan_def *chandef,
1694                                    u32 *changed)
1695 {
1696         struct ieee80211_local *local = sdata->local;
1697         struct ieee80211_chanctx_conf *conf;
1698         struct ieee80211_chanctx *ctx;
1699         const struct cfg80211_chan_def *compat;
1700         int ret;
1701
1702         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1703                                      IEEE80211_CHAN_DISABLED))
1704                 return -EINVAL;
1705
1706         mutex_lock(&local->chanctx_mtx);
1707         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1708                 ret = 0;
1709                 goto out;
1710         }
1711
1712         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1713             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1714                 ret = -EINVAL;
1715                 goto out;
1716         }
1717
1718         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1719                                          lockdep_is_held(&local->chanctx_mtx));
1720         if (!conf) {
1721                 ret = -EINVAL;
1722                 goto out;
1723         }
1724
1725         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1726
1727         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1728         if (!compat) {
1729                 ret = -EINVAL;
1730                 goto out;
1731         }
1732
1733         switch (ctx->replace_state) {
1734         case IEEE80211_CHANCTX_REPLACE_NONE:
1735                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1736                         ret = -EBUSY;
1737                         goto out;
1738                 }
1739                 break;
1740         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1741                 /* TODO: Perhaps the bandwidth change could be treated as a
1742                  * reservation itself? */
1743                 ret = -EBUSY;
1744                 goto out;
1745         case IEEE80211_CHANCTX_REPLACES_OTHER:
1746                 /* channel context that is going to replace another channel
1747                  * context doesn't really exist and shouldn't be assigned
1748                  * anywhere yet */
1749                 WARN_ON(1);
1750                 break;
1751         }
1752
1753         ieee80211_vif_update_chandef(sdata, chandef);
1754
1755         ieee80211_recalc_chanctx_chantype(local, ctx);
1756
1757         *changed |= BSS_CHANGED_BANDWIDTH;
1758         ret = 0;
1759  out:
1760         mutex_unlock(&local->chanctx_mtx);
1761         return ret;
1762 }
1763
1764 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1765 {
1766         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1767
1768         lockdep_assert_held(&sdata->local->mtx);
1769
1770         mutex_lock(&sdata->local->chanctx_mtx);
1771         __ieee80211_vif_release_channel(sdata);
1772         mutex_unlock(&sdata->local->chanctx_mtx);
1773 }
1774
1775 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1776 {
1777         struct ieee80211_local *local = sdata->local;
1778         struct ieee80211_sub_if_data *ap;
1779         struct ieee80211_chanctx_conf *conf;
1780
1781         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1782                 return;
1783
1784         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1785
1786         mutex_lock(&local->chanctx_mtx);
1787
1788         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1789                                          lockdep_is_held(&local->chanctx_mtx));
1790         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1791         mutex_unlock(&local->chanctx_mtx);
1792 }
1793
1794 void ieee80211_iter_chan_contexts_atomic(
1795         struct ieee80211_hw *hw,
1796         void (*iter)(struct ieee80211_hw *hw,
1797                      struct ieee80211_chanctx_conf *chanctx_conf,
1798                      void *data),
1799         void *iter_data)
1800 {
1801         struct ieee80211_local *local = hw_to_local(hw);
1802         struct ieee80211_chanctx *ctx;
1803
1804         rcu_read_lock();
1805         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1806                 if (ctx->driver_present)
1807                         iter(hw, &ctx->conf, iter_data);
1808         rcu_read_unlock();
1809 }
1810 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);