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