net/mac80211/chan.c

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