net/mac80211/chan.c

   1 /*
   2  * mac80211 - channel management
   3  */
   4
   5 #include <linux/nl80211.h>
   6 #include <linux/export.h>
   7 #include <linux/rtnetlink.h>
   8 #include <net/cfg80211.h>
   9 #include "ieee80211_i.h"
  10 #include "driver-ops.h"
  11
  12 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
  13                                           struct ieee80211_chanctx *ctx)
  14 {
  15         struct ieee80211_sub_if_data *sdata;
  16         int num = 0;
  17
  18         lockdep_assert_held(&local->chanctx_mtx);
  19
  20         list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
  21                 num++;
  22
  23         return num;
  24 }
  25
  26 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
  27                                           struct ieee80211_chanctx *ctx)
  28 {
  29         struct ieee80211_sub_if_data *sdata;
  30         int num = 0;
  31
  32         lockdep_assert_held(&local->chanctx_mtx);
  33
  34         list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
  35                 num++;
  36
  37         return num;
  38 }
  39
  40 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
  41                                struct ieee80211_chanctx *ctx)
  42 {
  43         return ieee80211_chanctx_num_assigned(local, ctx) +
  44                ieee80211_chanctx_num_reserved(local, ctx);
  45 }
  46
  47 static int ieee80211_num_chanctx(struct ieee80211_local *local)
  48 {
  49         struct ieee80211_chanctx *ctx;
  50         int num = 0;
  51
  52         lockdep_assert_held(&local->chanctx_mtx);
  53
  54         list_for_each_entry(ctx, &local->chanctx_list, list)
  55                 num++;
  56
  57         return num;
  58 }
  59
  60 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
  61 {
  62         lockdep_assert_held(&local->chanctx_mtx);
  63         return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
  64 }
  65
  66 static struct ieee80211_chanctx *
  67 ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
  68 {
  69         struct ieee80211_local *local __maybe_unused = sdata->local;
  70         struct ieee80211_chanctx_conf *conf;
  71
  72         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
  73                                          lockdep_is_held(&local->chanctx_mtx));
  74         if (!conf)
  75                 return NULL;
  76
  77         return container_of(conf, struct ieee80211_chanctx, conf);
  78 }
  79
  80 static const struct cfg80211_chan_def *
  81 ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
  82                                    struct ieee80211_chanctx *ctx,
  83                                    const struct cfg80211_chan_def *compat)
  84 {
  85         struct ieee80211_sub_if_data *sdata;
  86
  87         lockdep_assert_held(&local->chanctx_mtx);
  88
  89         list_for_each_entry(sdata, &ctx->reserved_vifs,
  90                             reserved_chanctx_list) {
  91                 if (!compat)
  92                         compat = &sdata->reserved_chandef;
  93
  94                 compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
  95                                                      compat);
  96                 if (!compat)
  97                         break;
  98         }
  99
 100         return compat;
 101 }
 102
 103 static const struct cfg80211_chan_def *
 104 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
 105                                        struct ieee80211_chanctx *ctx,
 106                                        const struct cfg80211_chan_def *compat)
 107 {
 108         struct ieee80211_sub_if_data *sdata;
 109
 110         lockdep_assert_held(&local->chanctx_mtx);
 111
 112         list_for_each_entry(sdata, &ctx->assigned_vifs,
 113                             assigned_chanctx_list) {
 114                 if (sdata->reserved_chanctx != NULL)
 115                         continue;
 116
 117                 if (!compat)
 118                         compat = &sdata->vif.bss_conf.chandef;
 119
 120                 compat = cfg80211_chandef_compatible(
 121                                 &sdata->vif.bss_conf.chandef, compat);
 122                 if (!compat)
 123                         break;
 124         }
 125
 126         return compat;
 127 }
 128
 129 static const struct cfg80211_chan_def *
 130 ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
 131                                    struct ieee80211_chanctx *ctx,
 132                                    const struct cfg80211_chan_def *compat)
 133 {
 134         lockdep_assert_held(&local->chanctx_mtx);
 135
 136         compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
 137         if (!compat)
 138                 return NULL;
 139
 140         compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
 141         if (!compat)
 142                 return NULL;
 143
 144         return compat;
 145 }
 146
 147 static bool
 148 ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
 149                                       struct ieee80211_chanctx *ctx,
 150                                       const struct cfg80211_chan_def *def)
 151 {
 152         lockdep_assert_held(&local->chanctx_mtx);
 153
 154         if (ieee80211_chanctx_combined_chandef(local, ctx, def))
 155                 return true;
 156
 157         if (!list_empty(&ctx->reserved_vifs) &&
 158             ieee80211_chanctx_reserved_chandef(local, ctx, def))
 159                 return true;
 160
 161         return false;
 162 }
 163
 164 static struct ieee80211_chanctx *
 165 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
 166                                    const struct cfg80211_chan_def *chandef,
 167                                    enum ieee80211_chanctx_mode mode)
 168 {
 169         struct ieee80211_chanctx *ctx;
 170
 171         lockdep_assert_held(&local->chanctx_mtx);
 172
 173         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 174                 return NULL;
 175
 176         list_for_each_entry(ctx, &local->chanctx_list, list) {
 177                 if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
 178                         continue;
 179
 180                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 181                         continue;
 182
 183                 if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
 184                                                            chandef))
 185                         continue;
 186
 187                 return ctx;
 188         }
 189
 190         return NULL;
 191 }
 192
 193 enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
 194 {
 195         switch (sta->bandwidth) {
 196         case IEEE80211_STA_RX_BW_20:
 197                 if (sta->ht_cap.ht_supported)
 198                         return NL80211_CHAN_WIDTH_20;
 199                 else
 200                         return NL80211_CHAN_WIDTH_20_NOHT;
 201         case IEEE80211_STA_RX_BW_40:
 202                 return NL80211_CHAN_WIDTH_40;
 203         case IEEE80211_STA_RX_BW_80:
 204                 return NL80211_CHAN_WIDTH_80;
 205         case IEEE80211_STA_RX_BW_160:
 206                 /*
 207                  * This applied for both 160 and 80+80. since we use
 208                  * the returned value to consider degradation of
 209                  * ctx->conf.min_def, we have to make sure to take
 210                  * the bigger one (NL80211_CHAN_WIDTH_160).
 211                  * Otherwise we might try degrading even when not
 212                  * needed, as the max required sta_bw returned (80+80)
 213                  * might be smaller than the configured bw (160).
 214                  */
 215                 return NL80211_CHAN_WIDTH_160;
 216         default:
 217                 WARN_ON(1);
 218                 return NL80211_CHAN_WIDTH_20;
 219         }
 220 }
 221
 222 static enum nl80211_chan_width
 223 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
 224 {
 225         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 226         struct sta_info *sta;
 227
 228         rcu_read_lock();
 229         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
 230                 if (sdata != sta->sdata &&
 231                     !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
 232                         continue;
 233
 234                 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_STATION:
 268                         /*
 269                          * The ap's sta->bandwidth is not set yet at this
 270                          * point, so take the width from the chandef, but
 271                          * account also for TDLS peers
 272                          */
 273                         width = max(vif->bss_conf.chandef.width,
 274                                     ieee80211_get_max_required_bw(sdata));
 275                         break;
 276                 case NL80211_IFTYPE_P2P_DEVICE:
 277                         continue;
 278                 case NL80211_IFTYPE_ADHOC:
 279                 case NL80211_IFTYPE_WDS:
 280                 case NL80211_IFTYPE_MESH_POINT:
 281                 case NL80211_IFTYPE_OCB:
 282                         width = vif->bss_conf.chandef.width;
 283                         break;
 284                 case NL80211_IFTYPE_UNSPECIFIED:
 285                 case NUM_NL80211_IFTYPES:
 286                 case NL80211_IFTYPE_MONITOR:
 287                 case NL80211_IFTYPE_P2P_CLIENT:
 288                 case NL80211_IFTYPE_P2P_GO:
 289                         WARN_ON_ONCE(1);
 290                 }
 291                 max_bw = max(max_bw, width);
 292         }
 293
 294         /* use the configured bandwidth in case of monitor interface */
 295         sdata = rcu_dereference(local->monitor_sdata);
 296         if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
 297                 max_bw = max(max_bw, conf->def.width);
 298
 299         rcu_read_unlock();
 300
 301         return max_bw;
 302 }
 303
 304 /*
 305  * recalc the min required chan width of the channel context, which is
 306  * the max of min required widths of all the interfaces bound to this
 307  * channel context.
 308  */
 309 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
 310                                       struct ieee80211_chanctx *ctx)
 311 {
 312         enum nl80211_chan_width max_bw;
 313         struct cfg80211_chan_def min_def;
 314
 315         lockdep_assert_held(&local->chanctx_mtx);
 316
 317         /* don't optimize 5MHz, 10MHz, and radar_enabled confs */
 318         if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
 319             ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
 320             ctx->conf.radar_enabled) {
 321                 ctx->conf.min_def = ctx->conf.def;
 322                 return;
 323         }
 324
 325         max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
 326
 327         /* downgrade chandef up to max_bw */
 328         min_def = ctx->conf.def;
 329         while (min_def.width > max_bw)
 330                 ieee80211_chandef_downgrade(&min_def);
 331
 332         if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
 333                 return;
 334
 335         ctx->conf.min_def = min_def;
 336         if (!ctx->driver_present)
 337                 return;
 338
 339         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
 340 }
 341
 342 static void ieee80211_change_chanctx(struct ieee80211_local *local,
 343                                      struct ieee80211_chanctx *ctx,
 344                                      const struct cfg80211_chan_def *chandef)
 345 {
 346         if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
 347                 return;
 348
 349         WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
 350
 351         ctx->conf.def = *chandef;
 352         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
 353         ieee80211_recalc_chanctx_min_def(local, ctx);
 354
 355         if (!local->use_chanctx) {
 356                 local->_oper_chandef = *chandef;
 357                 ieee80211_hw_config(local, 0);
 358         }
 359 }
 360
 361 static struct ieee80211_chanctx *
 362 ieee80211_find_chanctx(struct ieee80211_local *local,
 363                        const struct cfg80211_chan_def *chandef,
 364                        enum ieee80211_chanctx_mode mode)
 365 {
 366         struct ieee80211_chanctx *ctx;
 367
 368         lockdep_assert_held(&local->chanctx_mtx);
 369
 370         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 371                 return NULL;
 372
 373         list_for_each_entry(ctx, &local->chanctx_list, list) {
 374                 const struct cfg80211_chan_def *compat;
 375
 376                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
 377                         continue;
 378
 379                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 380                         continue;
 381
 382                 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
 383                 if (!compat)
 384                         continue;
 385
 386                 compat = ieee80211_chanctx_reserved_chandef(local, ctx,
 387                                                             compat);
 388                 if (!compat)
 389                         continue;
 390
 391                 ieee80211_change_chanctx(local, ctx, compat);
 392
 393                 return ctx;
 394         }
 395
 396         return NULL;
 397 }
 398
 399 bool ieee80211_is_radar_required(struct ieee80211_local *local)
 400 {
 401         struct ieee80211_sub_if_data *sdata;
 402
 403         lockdep_assert_held(&local->mtx);
 404
 405         rcu_read_lock();
 406         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 407                 if (sdata->radar_required) {
 408                         rcu_read_unlock();
 409                         return true;
 410                 }
 411         }
 412         rcu_read_unlock();
 413
 414         return false;
 415 }
 416
 417 static bool
 418 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
 419                                  struct ieee80211_chanctx *ctx)
 420 {
 421         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 422         struct ieee80211_sub_if_data *sdata;
 423         bool required = false;
 424
 425         lockdep_assert_held(&local->chanctx_mtx);
 426         lockdep_assert_held(&local->mtx);
 427
 428         rcu_read_lock();
 429         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 430                 if (!ieee80211_sdata_running(sdata))
 431                         continue;
 432                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 433                         continue;
 434                 if (!sdata->radar_required)
 435                         continue;
 436
 437                 required = true;
 438                 break;
 439         }
 440         rcu_read_unlock();
 441
 442         return required;
 443 }
 444
 445 static struct ieee80211_chanctx *
 446 ieee80211_alloc_chanctx(struct ieee80211_local *local,
 447                         const struct cfg80211_chan_def *chandef,
 448                         enum ieee80211_chanctx_mode mode)
 449 {
 450         struct ieee80211_chanctx *ctx;
 451
 452         lockdep_assert_held(&local->chanctx_mtx);
 453
 454         ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
 455         if (!ctx)
 456                 return NULL;
 457
 458         INIT_LIST_HEAD(&ctx->assigned_vifs);
 459         INIT_LIST_HEAD(&ctx->reserved_vifs);
 460         ctx->conf.def = *chandef;
 461         ctx->conf.rx_chains_static = 1;
 462         ctx->conf.rx_chains_dynamic = 1;
 463         ctx->mode = mode;
 464         ctx->conf.radar_enabled = false;
 465         ieee80211_recalc_chanctx_min_def(local, ctx);
 466
 467         return ctx;
 468 }
 469
 470 static int ieee80211_add_chanctx(struct ieee80211_local *local,
 471                                  struct ieee80211_chanctx *ctx)
 472 {
 473         u32 changed;
 474         int err;
 475
 476         lockdep_assert_held(&local->mtx);
 477         lockdep_assert_held(&local->chanctx_mtx);
 478
 479         if (!local->use_chanctx)
 480                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 481
 482         /* turn idle off *before* setting channel -- some drivers need that */
 483         changed = ieee80211_idle_off(local);
 484         if (changed)
 485                 ieee80211_hw_config(local, changed);
 486
 487         if (!local->use_chanctx) {
 488                 local->_oper_chandef = ctx->conf.def;
 489                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 490         } else {
 491                 err = drv_add_chanctx(local, ctx);
 492                 if (err) {
 493                         ieee80211_recalc_idle(local);
 494                         return err;
 495                 }
 496         }
 497
 498         return 0;
 499 }
 500
 501 static struct ieee80211_chanctx *
 502 ieee80211_new_chanctx(struct ieee80211_local *local,
 503                       const struct cfg80211_chan_def *chandef,
 504                       enum ieee80211_chanctx_mode mode)
 505 {
 506         struct ieee80211_chanctx *ctx;
 507         int err;
 508
 509         lockdep_assert_held(&local->mtx);
 510         lockdep_assert_held(&local->chanctx_mtx);
 511
 512         ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 513         if (!ctx)
 514                 return ERR_PTR(-ENOMEM);
 515
 516         err = ieee80211_add_chanctx(local, ctx);
 517         if (err) {
 518                 kfree(ctx);
 519                 return ERR_PTR(err);
 520         }
 521
 522         list_add_rcu(&ctx->list, &local->chanctx_list);
 523         return ctx;
 524 }
 525
 526 static void ieee80211_del_chanctx(struct ieee80211_local *local,
 527                                   struct ieee80211_chanctx *ctx)
 528 {
 529         lockdep_assert_held(&local->chanctx_mtx);
 530
 531         if (!local->use_chanctx) {
 532                 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
 533                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 534                 chandef->center_freq1 = chandef->chan->center_freq;
 535                 chandef->center_freq2 = 0;
 536
 537                 /* NOTE: Disabling radar is only valid here for
 538                  * single channel context. To be sure, check it ...
 539                  */
 540                 WARN_ON(local->hw.conf.radar_enabled &&
 541                         !list_empty(&local->chanctx_list));
 542
 543                 local->hw.conf.radar_enabled = false;
 544
 545                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 546         } else {
 547                 drv_remove_chanctx(local, ctx);
 548         }
 549
 550         ieee80211_recalc_idle(local);
 551 }
 552
 553 static void ieee80211_free_chanctx(struct ieee80211_local *local,
 554                                    struct ieee80211_chanctx *ctx)
 555 {
 556         lockdep_assert_held(&local->chanctx_mtx);
 557
 558         WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
 559
 560         list_del_rcu(&ctx->list);
 561         ieee80211_del_chanctx(local, ctx);
 562         kfree_rcu(ctx, rcu_head);
 563 }
 564
 565 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 566                                        struct ieee80211_chanctx *ctx)
 567 {
 568         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 569         struct ieee80211_sub_if_data *sdata;
 570         const struct cfg80211_chan_def *compat = NULL;
 571         struct sta_info *sta;
 572
 573         lockdep_assert_held(&local->chanctx_mtx);
 574
 575         rcu_read_lock();
 576         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 577
 578                 if (!ieee80211_sdata_running(sdata))
 579                         continue;
 580                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 581                         continue;
 582                 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 583                         continue;
 584
 585                 if (!compat)
 586                         compat = &sdata->vif.bss_conf.chandef;
 587
 588                 compat = cfg80211_chandef_compatible(
 589                                 &sdata->vif.bss_conf.chandef, compat);
 590                 if (WARN_ON_ONCE(!compat))
 591                         break;
 592         }
 593
 594         /* TDLS peers can sometimes affect the chandef width */
 595         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 596                 if (!sta->uploaded ||
 597                     !test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW) ||
 598                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
 599                     !sta->tdls_chandef.chan)
 600                         continue;
 601
 602                 compat = cfg80211_chandef_compatible(&sta->tdls_chandef,
 603                                                      compat);
 604                 if (WARN_ON_ONCE(!compat))
 605                         break;
 606         }
 607         rcu_read_unlock();
 608
 609         if (!compat)
 610                 return;
 611
 612         ieee80211_change_chanctx(local, ctx, compat);
 613 }
 614
 615 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
 616                                            struct ieee80211_chanctx *chanctx)
 617 {
 618         bool radar_enabled;
 619
 620         lockdep_assert_held(&local->chanctx_mtx);
 621         /* for ieee80211_is_radar_required */
 622         lockdep_assert_held(&local->mtx);
 623
 624         radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
 625
 626         if (radar_enabled == chanctx->conf.radar_enabled)
 627                 return;
 628
 629         chanctx->conf.radar_enabled = radar_enabled;
 630
 631         if (!local->use_chanctx) {
 632                 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
 633                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 634         }
 635
 636         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
 637 }
 638
 639 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 640                                         struct ieee80211_chanctx *new_ctx)
 641 {
 642         struct ieee80211_local *local = sdata->local;
 643         struct ieee80211_chanctx_conf *conf;
 644         struct ieee80211_chanctx *curr_ctx = NULL;
 645         int ret = 0;
 646
 647         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 648                                          lockdep_is_held(&local->chanctx_mtx));
 649
 650         if (conf) {
 651                 curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
 652
 653                 drv_unassign_vif_chanctx(local, sdata, curr_ctx);
 654                 conf = NULL;
 655                 list_del(&sdata->assigned_chanctx_list);
 656         }
 657
 658         if (new_ctx) {
 659                 ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
 660                 if (ret)
 661                         goto out;
 662
 663                 conf = &new_ctx->conf;
 664                 list_add(&sdata->assigned_chanctx_list,
 665                          &new_ctx->assigned_vifs);
 666         }
 667
 668 out:
 669         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
 670
 671         sdata->vif.bss_conf.idle = !conf;
 672
 673         if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
 674                 ieee80211_recalc_chanctx_chantype(local, curr_ctx);
 675                 ieee80211_recalc_smps_chanctx(local, curr_ctx);
 676                 ieee80211_recalc_radar_chanctx(local, curr_ctx);
 677                 ieee80211_recalc_chanctx_min_def(local, curr_ctx);
 678         }
 679
 680         if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
 681                 ieee80211_recalc_txpower(sdata, false);
 682                 ieee80211_recalc_chanctx_min_def(local, new_ctx);
 683         }
 684
 685         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
 686             sdata->vif.type != NL80211_IFTYPE_MONITOR)
 687                 ieee80211_bss_info_change_notify(sdata,
 688                                                  BSS_CHANGED_IDLE);
 689
 690         ieee80211_check_fast_xmit_iface(sdata);
 691
 692         return ret;
 693 }
 694
 695 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 696                                    struct ieee80211_chanctx *chanctx)
 697 {
 698         struct ieee80211_sub_if_data *sdata;
 699         u8 rx_chains_static, rx_chains_dynamic;
 700
 701         lockdep_assert_held(&local->chanctx_mtx);
 702
 703         rx_chains_static = 1;
 704         rx_chains_dynamic = 1;
 705
 706         rcu_read_lock();
 707         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 708                 u8 needed_static, needed_dynamic;
 709
 710                 if (!ieee80211_sdata_running(sdata))
 711                         continue;
 712
 713                 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
 714                                                 &chanctx->conf)
 715                         continue;
 716
 717                 switch (sdata->vif.type) {
 718                 case NL80211_IFTYPE_P2P_DEVICE:
 719                         continue;
 720                 case NL80211_IFTYPE_STATION:
 721                         if (!sdata->u.mgd.associated)
 722                                 continue;
 723                         break;
 724                 case NL80211_IFTYPE_AP_VLAN:
 725                         continue;
 726                 case NL80211_IFTYPE_AP:
 727                 case NL80211_IFTYPE_ADHOC:
 728                 case NL80211_IFTYPE_WDS:
 729                 case NL80211_IFTYPE_MESH_POINT:
 730                 case NL80211_IFTYPE_OCB:
 731                         break;
 732                 default:
 733                         WARN_ON_ONCE(1);
 734                 }
 735
 736                 switch (sdata->smps_mode) {
 737                 default:
 738                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
 739                                   sdata->smps_mode);
 740                         /* fall through */
 741                 case IEEE80211_SMPS_OFF:
 742                         needed_static = sdata->needed_rx_chains;
 743                         needed_dynamic = sdata->needed_rx_chains;
 744                         break;
 745                 case IEEE80211_SMPS_DYNAMIC:
 746                         needed_static = 1;
 747                         needed_dynamic = sdata->needed_rx_chains;
 748                         break;
 749                 case IEEE80211_SMPS_STATIC:
 750                         needed_static = 1;
 751                         needed_dynamic = 1;
 752                         break;
 753                 }
 754
 755                 rx_chains_static = max(rx_chains_static, needed_static);
 756                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
 757         }
 758
 759         /* Disable SMPS for the monitor interface */
 760         sdata = rcu_dereference(local->monitor_sdata);
 761         if (sdata &&
 762             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
 763                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
 764
 765         rcu_read_unlock();
 766
 767         if (!local->use_chanctx) {
 768                 if (rx_chains_static > 1)
 769                         local->smps_mode = IEEE80211_SMPS_OFF;
 770                 else if (rx_chains_dynamic > 1)
 771                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
 772                 else
 773                         local->smps_mode = IEEE80211_SMPS_STATIC;
 774                 ieee80211_hw_config(local, 0);
 775         }
 776
 777         if (rx_chains_static == chanctx->conf.rx_chains_static &&
 778             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
 779                 return;
 780
 781         chanctx->conf.rx_chains_static = rx_chains_static;
 782         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
 783         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
 784 }
 785
 786 static void
 787 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 788                                       bool clear)
 789 {
 790         struct ieee80211_local *local __maybe_unused = sdata->local;
 791         struct ieee80211_sub_if_data *vlan;
 792         struct ieee80211_chanctx_conf *conf;
 793
 794         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
 795                 return;
 796
 797         lockdep_assert_held(&local->mtx);
 798
 799         /* Check that conf exists, even when clearing this function
 800          * must be called with the AP's channel context still there
 801          * as it would otherwise cause VLANs to have an invalid
 802          * channel context pointer for a while, possibly pointing
 803          * to a channel context that has already been freed.
 804          */
 805         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 806                                          lockdep_is_held(&local->chanctx_mtx));
 807         WARN_ON(!conf);
 808
 809         if (clear)
 810                 conf = NULL;
 811
 812         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 813                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
 814 }
 815
 816 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 817                                          bool clear)
 818 {
 819         struct ieee80211_local *local = sdata->local;
 820
 821         mutex_lock(&local->chanctx_mtx);
 822
 823         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
 824
 825         mutex_unlock(&local->chanctx_mtx);
 826 }
 827
 828 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
 829 {
 830         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
 831
 832         lockdep_assert_held(&sdata->local->chanctx_mtx);
 833
 834         if (WARN_ON(!ctx))
 835                 return -EINVAL;
 836
 837         list_del(&sdata->reserved_chanctx_list);
 838         sdata->reserved_chanctx = NULL;
 839
 840         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
 841                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
 842                         if (WARN_ON(!ctx->replace_ctx))
 843                                 return -EINVAL;
 844
 845                         WARN_ON(ctx->replace_ctx->replace_state !=
 846                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
 847                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
 848
 849                         ctx->replace_ctx->replace_ctx = NULL;
 850                         ctx->replace_ctx->replace_state =
 851                                         IEEE80211_CHANCTX_REPLACE_NONE;
 852
 853                         list_del_rcu(&ctx->list);
 854                         kfree_rcu(ctx, rcu_head);
 855                 } else {
 856                         ieee80211_free_chanctx(sdata->local, ctx);
 857                 }
 858         }
 859
 860         return 0;
 861 }
 862
 863 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
 864                                   const struct cfg80211_chan_def *chandef,
 865                                   enum ieee80211_chanctx_mode mode,
 866                                   bool radar_required)
 867 {
 868         struct ieee80211_local *local = sdata->local;
 869         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
 870
 871         lockdep_assert_held(&local->chanctx_mtx);
 872
 873         curr_ctx = ieee80211_vif_get_chanctx(sdata);
 874         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
 875                 return -ENOTSUPP;
 876
 877         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
 878         if (!new_ctx) {
 879                 if (ieee80211_can_create_new_chanctx(local)) {
 880                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
 881                         if (IS_ERR(new_ctx))
 882                                 return PTR_ERR(new_ctx);
 883                 } else {
 884                         if (!curr_ctx ||
 885                             (curr_ctx->replace_state ==
 886                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 887                             !list_empty(&curr_ctx->reserved_vifs)) {
 888                                 /*
 889                                  * Another vif already requested this context
 890                                  * for a reservation. Find another one hoping
 891                                  * all vifs assigned to it will also switch
 892                                  * soon enough.
 893                                  *
 894                                  * TODO: This needs a little more work as some
 895                                  * cases (more than 2 chanctx capable devices)
 896                                  * may fail which could otherwise succeed
 897                                  * provided some channel context juggling was
 898                                  * performed.
 899                                  *
 900                                  * Consider ctx1..3, vif1..6, each ctx has 2
 901                                  * vifs. vif1 and vif2 from ctx1 request new
 902                                  * different chandefs starting 2 in-place
 903                                  * reserations with ctx4 and ctx5 replacing
 904                                  * ctx1 and ctx2 respectively. Next vif5 and
 905                                  * vif6 from ctx3 reserve ctx4. If vif3 and
 906                                  * vif4 remain on ctx2 as they are then this
 907                                  * fails unless `replace_ctx` from ctx5 is
 908                                  * replaced with ctx3.
 909                                  */
 910                                 list_for_each_entry(ctx, &local->chanctx_list,
 911                                                     list) {
 912                                         if (ctx->replace_state !=
 913                                             IEEE80211_CHANCTX_REPLACE_NONE)
 914                                                 continue;
 915
 916                                         if (!list_empty(&ctx->reserved_vifs))
 917                                                 continue;
 918
 919                                         curr_ctx = ctx;
 920                                         break;
 921                                 }
 922                         }
 923
 924                         /*
 925                          * If that's true then all available contexts already
 926                          * have reservations and cannot be used.
 927                          */
 928                         if (!curr_ctx ||
 929                             (curr_ctx->replace_state ==
 930                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 931                             !list_empty(&curr_ctx->reserved_vifs))
 932                                 return -EBUSY;
 933
 934                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 935                         if (!new_ctx)
 936                                 return -ENOMEM;
 937
 938                         new_ctx->replace_ctx = curr_ctx;
 939                         new_ctx->replace_state =
 940                                         IEEE80211_CHANCTX_REPLACES_OTHER;
 941
 942                         curr_ctx->replace_ctx = new_ctx;
 943                         curr_ctx->replace_state =
 944                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
 945
 946                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
 947                 }
 948         }
 949
 950         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
 951         sdata->reserved_chanctx = new_ctx;
 952         sdata->reserved_chandef = *chandef;
 953         sdata->reserved_radar_required = radar_required;
 954         sdata->reserved_ready = false;
 955
 956         return 0;
 957 }
 958
 959 static void
 960 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
 961 {
 962         switch (sdata->vif.type) {
 963         case NL80211_IFTYPE_ADHOC:
 964         case NL80211_IFTYPE_AP:
 965         case NL80211_IFTYPE_MESH_POINT:
 966         case NL80211_IFTYPE_OCB:
 967                 ieee80211_queue_work(&sdata->local->hw,
 968                                      &sdata->csa_finalize_work);
 969                 break;
 970         case NL80211_IFTYPE_STATION:
 971                 ieee80211_queue_work(&sdata->local->hw,
 972                                      &sdata->u.mgd.chswitch_work);
 973                 break;
 974         case NL80211_IFTYPE_UNSPECIFIED:
 975         case NL80211_IFTYPE_AP_VLAN:
 976         case NL80211_IFTYPE_WDS:
 977         case NL80211_IFTYPE_MONITOR:
 978         case NL80211_IFTYPE_P2P_CLIENT:
 979         case NL80211_IFTYPE_P2P_GO:
 980         case NL80211_IFTYPE_P2P_DEVICE:
 981         case NUM_NL80211_IFTYPES:
 982                 WARN_ON(1);
 983                 break;
 984         }
 985 }
 986
 987 static void
 988 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
 989                              const struct cfg80211_chan_def *chandef)
 990 {
 991         struct ieee80211_sub_if_data *vlan;
 992
 993         sdata->vif.bss_conf.chandef = *chandef;
 994
 995         if (sdata->vif.type != NL80211_IFTYPE_AP)
 996                 return;
 997
 998         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 999                 vlan->vif.bss_conf.chandef = *chandef;
1000 }
1001
1002 static int
1003 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
1004 {
1005         struct ieee80211_local *local = sdata->local;
1006         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1007         struct ieee80211_chanctx *old_ctx, *new_ctx;
1008         const struct cfg80211_chan_def *chandef;
1009         u32 changed = 0;
1010         int err;
1011
1012         lockdep_assert_held(&local->mtx);
1013         lockdep_assert_held(&local->chanctx_mtx);
1014
1015         new_ctx = sdata->reserved_chanctx;
1016         old_ctx = ieee80211_vif_get_chanctx(sdata);
1017
1018         if (WARN_ON(!sdata->reserved_ready))
1019                 return -EBUSY;
1020
1021         if (WARN_ON(!new_ctx))
1022                 return -EINVAL;
1023
1024         if (WARN_ON(!old_ctx))
1025                 return -EINVAL;
1026
1027         if (WARN_ON(new_ctx->replace_state ==
1028                     IEEE80211_CHANCTX_REPLACES_OTHER))
1029                 return -EINVAL;
1030
1031         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1032                                 &sdata->reserved_chandef);
1033         if (WARN_ON(!chandef))
1034                 return -EINVAL;
1035
1036         ieee80211_change_chanctx(local, new_ctx, chandef);
1037
1038         vif_chsw[0].vif = &sdata->vif;
1039         vif_chsw[0].old_ctx = &old_ctx->conf;
1040         vif_chsw[0].new_ctx = &new_ctx->conf;
1041
1042         list_del(&sdata->reserved_chanctx_list);
1043         sdata->reserved_chanctx = NULL;
1044
1045         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1046                                      CHANCTX_SWMODE_REASSIGN_VIF);
1047         if (err) {
1048                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1049                         ieee80211_free_chanctx(local, new_ctx);
1050
1051                 goto out;
1052         }
1053
1054         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1055         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1056
1057         if (sdata->vif.type == NL80211_IFTYPE_AP)
1058                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1059
1060         ieee80211_check_fast_xmit_iface(sdata);
1061
1062         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1063                 ieee80211_free_chanctx(local, old_ctx);
1064
1065         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1066                 changed = BSS_CHANGED_BANDWIDTH;
1067
1068         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1069
1070         ieee80211_recalc_smps_chanctx(local, new_ctx);
1071         ieee80211_recalc_radar_chanctx(local, new_ctx);
1072         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1073
1074         if (changed)
1075                 ieee80211_bss_info_change_notify(sdata, changed);
1076
1077 out:
1078         ieee80211_vif_chanctx_reservation_complete(sdata);
1079         return err;
1080 }
1081
1082 static int
1083 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1084 {
1085         struct ieee80211_local *local = sdata->local;
1086         struct ieee80211_chanctx *old_ctx, *new_ctx;
1087         const struct cfg80211_chan_def *chandef;
1088         int err;
1089
1090         old_ctx = ieee80211_vif_get_chanctx(sdata);
1091         new_ctx = sdata->reserved_chanctx;
1092
1093         if (WARN_ON(!sdata->reserved_ready))
1094                 return -EINVAL;
1095
1096         if (WARN_ON(old_ctx))
1097                 return -EINVAL;
1098
1099         if (WARN_ON(!new_ctx))
1100                 return -EINVAL;
1101
1102         if (WARN_ON(new_ctx->replace_state ==
1103                     IEEE80211_CHANCTX_REPLACES_OTHER))
1104                 return -EINVAL;
1105
1106         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1107                                 &sdata->reserved_chandef);
1108         if (WARN_ON(!chandef))
1109                 return -EINVAL;
1110
1111         ieee80211_change_chanctx(local, new_ctx, chandef);
1112
1113         list_del(&sdata->reserved_chanctx_list);
1114         sdata->reserved_chanctx = NULL;
1115
1116         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1117         if (err) {
1118                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1119                         ieee80211_free_chanctx(local, new_ctx);
1120
1121                 goto out;
1122         }
1123
1124 out:
1125         ieee80211_vif_chanctx_reservation_complete(sdata);
1126         return err;
1127 }
1128
1129 static bool
1130 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1131 {
1132         struct ieee80211_chanctx *old_ctx, *new_ctx;
1133
1134         lockdep_assert_held(&sdata->local->chanctx_mtx);
1135
1136         new_ctx = sdata->reserved_chanctx;
1137         old_ctx = ieee80211_vif_get_chanctx(sdata);
1138
1139         if (!old_ctx)
1140                 return false;
1141
1142         if (WARN_ON(!new_ctx))
1143                 return false;
1144
1145         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1146                 return false;
1147
1148         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1149                 return false;
1150
1151         return true;
1152 }
1153
1154 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1155                                         struct ieee80211_chanctx *new_ctx)
1156 {
1157         const struct cfg80211_chan_def *chandef;
1158
1159         lockdep_assert_held(&local->mtx);
1160         lockdep_assert_held(&local->chanctx_mtx);
1161
1162         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1163         if (WARN_ON(!chandef))
1164                 return -EINVAL;
1165
1166         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1167         local->_oper_chandef = *chandef;
1168         ieee80211_hw_config(local, 0);
1169
1170         return 0;
1171 }
1172
1173 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1174                                       int n_vifs)
1175 {
1176         struct ieee80211_vif_chanctx_switch *vif_chsw;
1177         struct ieee80211_sub_if_data *sdata;
1178         struct ieee80211_chanctx *ctx, *old_ctx;
1179         int i, err;
1180
1181         lockdep_assert_held(&local->mtx);
1182         lockdep_assert_held(&local->chanctx_mtx);
1183
1184         vif_chsw = kzalloc(sizeof(vif_chsw[0]) * n_vifs, GFP_KERNEL);
1185         if (!vif_chsw)
1186                 return -ENOMEM;
1187
1188         i = 0;
1189         list_for_each_entry(ctx, &local->chanctx_list, list) {
1190                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1191                         continue;
1192
1193                 if (WARN_ON(!ctx->replace_ctx)) {
1194                         err = -EINVAL;
1195                         goto out;
1196                 }
1197
1198                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1199                                     reserved_chanctx_list) {
1200                         if (!ieee80211_vif_has_in_place_reservation(
1201                                         sdata))
1202                                 continue;
1203
1204                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1205                         vif_chsw[i].vif = &sdata->vif;
1206                         vif_chsw[i].old_ctx = &old_ctx->conf;
1207                         vif_chsw[i].new_ctx = &ctx->conf;
1208
1209                         i++;
1210                 }
1211         }
1212
1213         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1214                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1215
1216 out:
1217         kfree(vif_chsw);
1218         return err;
1219 }
1220
1221 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1222 {
1223         struct ieee80211_chanctx *ctx;
1224         int err;
1225
1226         lockdep_assert_held(&local->mtx);
1227         lockdep_assert_held(&local->chanctx_mtx);
1228
1229         list_for_each_entry(ctx, &local->chanctx_list, list) {
1230                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1231                         continue;
1232
1233                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1234                         continue;
1235
1236                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1237                 err = ieee80211_add_chanctx(local, ctx);
1238                 if (err)
1239                         goto err;
1240         }
1241
1242         return 0;
1243
1244 err:
1245         WARN_ON(ieee80211_add_chanctx(local, ctx));
1246         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1247                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1248                         continue;
1249
1250                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1251                         continue;
1252
1253                 ieee80211_del_chanctx(local, ctx);
1254                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1255         }
1256
1257         return err;
1258 }
1259
1260 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1261 {
1262         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1263         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1264         struct ieee80211_chanctx *new_ctx = NULL;
1265         int i, err, n_assigned, n_reserved, n_ready;
1266         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1267
1268         lockdep_assert_held(&local->mtx);
1269         lockdep_assert_held(&local->chanctx_mtx);
1270
1271         /*
1272          * If there are 2 independent pairs of channel contexts performing
1273          * cross-switch of their vifs this code will still wait until both are
1274          * ready even though it could be possible to switch one before the
1275          * other is ready.
1276          *
1277          * For practical reasons and code simplicity just do a single huge
1278          * switch.
1279          */
1280
1281         /*
1282          * Verify if the reservation is still feasible.
1283          *  - if it's not then disconnect
1284          *  - if it is but not all vifs necessary are ready then defer
1285          */
1286
1287         list_for_each_entry(ctx, &local->chanctx_list, list) {
1288                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1289                         continue;
1290
1291                 if (WARN_ON(!ctx->replace_ctx)) {
1292                         err = -EINVAL;
1293                         goto err;
1294                 }
1295
1296                 if (!local->use_chanctx)
1297                         new_ctx = ctx;
1298
1299                 n_ctx++;
1300
1301                 n_assigned = 0;
1302                 n_reserved = 0;
1303                 n_ready = 0;
1304
1305                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1306                                     assigned_chanctx_list) {
1307                         n_assigned++;
1308                         if (sdata->reserved_chanctx) {
1309                                 n_reserved++;
1310                                 if (sdata->reserved_ready)
1311                                         n_ready++;
1312                         }
1313                 }
1314
1315                 if (n_assigned != n_reserved) {
1316                         if (n_ready == n_reserved) {
1317                                 wiphy_info(local->hw.wiphy,
1318                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1319                                 err = -EBUSY;
1320                                 goto err;
1321                         }
1322
1323                         return -EAGAIN;
1324                 }
1325
1326                 ctx->conf.radar_enabled = false;
1327                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1328                                     reserved_chanctx_list) {
1329                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1330                             !sdata->reserved_ready)
1331                                 return -EAGAIN;
1332
1333                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1334                         if (old_ctx) {
1335                                 if (old_ctx->replace_state ==
1336                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1337                                         n_vifs_switch++;
1338                                 else
1339                                         n_vifs_assign++;
1340                         } else {
1341                                 n_vifs_ctxless++;
1342                         }
1343
1344                         if (sdata->reserved_radar_required)
1345                                 ctx->conf.radar_enabled = true;
1346                 }
1347         }
1348
1349         if (WARN_ON(n_ctx == 0) ||
1350             WARN_ON(n_vifs_switch == 0 &&
1351                     n_vifs_assign == 0 &&
1352                     n_vifs_ctxless == 0) ||
1353             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1354             WARN_ON(!new_ctx && !local->use_chanctx)) {
1355                 err = -EINVAL;
1356                 goto err;
1357         }
1358
1359         /*
1360          * All necessary vifs are ready. Perform the switch now depending on
1361          * reservations and driver capabilities.
1362          */
1363
1364         if (local->use_chanctx) {
1365                 if (n_vifs_switch > 0) {
1366                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1367                         if (err)
1368                                 goto err;
1369                 }
1370
1371                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1372                         err = ieee80211_chsw_switch_ctxs(local);
1373                         if (err)
1374                                 goto err;
1375                 }
1376         } else {
1377                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1378                 if (err)
1379                         goto err;
1380         }
1381
1382         /*
1383          * Update all structures, values and pointers to point to new channel
1384          * context(s).
1385          */
1386
1387         i = 0;
1388         list_for_each_entry(ctx, &local->chanctx_list, list) {
1389                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1390                         continue;
1391
1392                 if (WARN_ON(!ctx->replace_ctx)) {
1393                         err = -EINVAL;
1394                         goto err;
1395                 }
1396
1397                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1398                                     reserved_chanctx_list) {
1399                         u32 changed = 0;
1400
1401                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1402                                 continue;
1403
1404                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1405
1406                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1407                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1408                                                                       false);
1409
1410                         ieee80211_check_fast_xmit_iface(sdata);
1411
1412                         sdata->radar_required = sdata->reserved_radar_required;
1413
1414                         if (sdata->vif.bss_conf.chandef.width !=
1415                             sdata->reserved_chandef.width)
1416                                 changed = BSS_CHANGED_BANDWIDTH;
1417
1418                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1419                         if (changed)
1420                                 ieee80211_bss_info_change_notify(sdata,
1421                                                                  changed);
1422
1423                         ieee80211_recalc_txpower(sdata, false);
1424                 }
1425
1426                 ieee80211_recalc_chanctx_chantype(local, ctx);
1427                 ieee80211_recalc_smps_chanctx(local, ctx);
1428                 ieee80211_recalc_radar_chanctx(local, ctx);
1429                 ieee80211_recalc_chanctx_min_def(local, ctx);
1430
1431                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1432                                          reserved_chanctx_list) {
1433                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1434                                 continue;
1435
1436                         list_del(&sdata->reserved_chanctx_list);
1437                         list_move(&sdata->assigned_chanctx_list,
1438                                   &ctx->assigned_vifs);
1439                         sdata->reserved_chanctx = NULL;
1440
1441                         ieee80211_vif_chanctx_reservation_complete(sdata);
1442                 }
1443
1444                 /*
1445                  * This context might have been a dependency for an already
1446                  * ready re-assign reservation interface that was deferred. Do
1447                  * not propagate error to the caller though. The in-place
1448                  * reservation for originally requested interface has already
1449                  * succeeded at this point.
1450                  */
1451                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1452                                          reserved_chanctx_list) {
1453                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1454                                         sdata)))
1455                                 continue;
1456
1457                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1458                                 continue;
1459
1460                         if (!sdata->reserved_ready)
1461                                 continue;
1462
1463                         if (ieee80211_vif_get_chanctx(sdata))
1464                                 err = ieee80211_vif_use_reserved_reassign(
1465                                                 sdata);
1466                         else
1467                                 err = ieee80211_vif_use_reserved_assign(sdata);
1468
1469                         if (err) {
1470                                 sdata_info(sdata,
1471                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1472                                            err);
1473                                 ieee80211_vif_unreserve_chanctx(sdata);
1474                                 cfg80211_stop_iface(local->hw.wiphy,
1475                                                     &sdata->wdev,
1476                                                     GFP_KERNEL);
1477                         }
1478                 }
1479         }
1480
1481         /*
1482          * Finally free old contexts
1483          */
1484
1485         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1486                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1487                         continue;
1488
1489                 ctx->replace_ctx->replace_ctx = NULL;
1490                 ctx->replace_ctx->replace_state =
1491                                 IEEE80211_CHANCTX_REPLACE_NONE;
1492
1493                 list_del_rcu(&ctx->list);
1494                 kfree_rcu(ctx, rcu_head);
1495         }
1496
1497         return 0;
1498
1499 err:
1500         list_for_each_entry(ctx, &local->chanctx_list, list) {
1501                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1502                         continue;
1503
1504                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1505                                          reserved_chanctx_list) {
1506                         ieee80211_vif_unreserve_chanctx(sdata);
1507                         ieee80211_vif_chanctx_reservation_complete(sdata);
1508                 }
1509         }
1510
1511         return err;
1512 }
1513
1514 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1515 {
1516         struct ieee80211_local *local = sdata->local;
1517         struct ieee80211_chanctx_conf *conf;
1518         struct ieee80211_chanctx *ctx;
1519         bool use_reserved_switch = false;
1520
1521         lockdep_assert_held(&local->chanctx_mtx);
1522
1523         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1524                                          lockdep_is_held(&local->chanctx_mtx));
1525         if (!conf)
1526                 return;
1527
1528         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1529
1530         if (sdata->reserved_chanctx) {
1531                 if (sdata->reserved_chanctx->replace_state ==
1532                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1533                     ieee80211_chanctx_num_reserved(local,
1534                                                    sdata->reserved_chanctx) > 1)
1535                         use_reserved_switch = true;
1536
1537                 ieee80211_vif_unreserve_chanctx(sdata);
1538         }
1539
1540         ieee80211_assign_vif_chanctx(sdata, NULL);
1541         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1542                 ieee80211_free_chanctx(local, ctx);
1543
1544         sdata->radar_required = false;
1545
1546         /* Unreserving may ready an in-place reservation. */
1547         if (use_reserved_switch)
1548                 ieee80211_vif_use_reserved_switch(local);
1549 }
1550
1551 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1552                               const struct cfg80211_chan_def *chandef,
1553                               enum ieee80211_chanctx_mode mode)
1554 {
1555         struct ieee80211_local *local = sdata->local;
1556         struct ieee80211_chanctx *ctx;
1557         u8 radar_detect_width = 0;
1558         int ret;
1559
1560         lockdep_assert_held(&local->mtx);
1561
1562         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1563
1564         mutex_lock(&local->chanctx_mtx);
1565
1566         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1567                                             chandef,
1568                                             sdata->wdev.iftype);
1569         if (ret < 0)
1570                 goto out;
1571         if (ret > 0)
1572                 radar_detect_width = BIT(chandef->width);
1573
1574         sdata->radar_required = ret;
1575
1576         ret = ieee80211_check_combinations(sdata, chandef, mode,
1577                                            radar_detect_width);
1578         if (ret < 0)
1579                 goto out;
1580
1581         __ieee80211_vif_release_channel(sdata);
1582
1583         ctx = ieee80211_find_chanctx(local, chandef, mode);
1584         if (!ctx)
1585                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1586         if (IS_ERR(ctx)) {
1587                 ret = PTR_ERR(ctx);
1588                 goto out;
1589         }
1590
1591         ieee80211_vif_update_chandef(sdata, chandef);
1592
1593         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1594         if (ret) {
1595                 /* if assign fails refcount stays the same */
1596                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1597                         ieee80211_free_chanctx(local, ctx);
1598                 goto out;
1599         }
1600
1601         ieee80211_recalc_smps_chanctx(local, ctx);
1602         ieee80211_recalc_radar_chanctx(local, ctx);
1603  out:
1604         if (ret)
1605                 sdata->radar_required = false;
1606
1607         mutex_unlock(&local->chanctx_mtx);
1608         return ret;
1609 }
1610
1611 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1612 {
1613         struct ieee80211_local *local = sdata->local;
1614         struct ieee80211_chanctx *new_ctx;
1615         struct ieee80211_chanctx *old_ctx;
1616         int err;
1617
1618         lockdep_assert_held(&local->mtx);
1619         lockdep_assert_held(&local->chanctx_mtx);
1620
1621         new_ctx = sdata->reserved_chanctx;
1622         old_ctx = ieee80211_vif_get_chanctx(sdata);
1623
1624         if (WARN_ON(!new_ctx))
1625                 return -EINVAL;
1626
1627         if (WARN_ON(new_ctx->replace_state ==
1628                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1629                 return -EINVAL;
1630
1631         if (WARN_ON(sdata->reserved_ready))
1632                 return -EINVAL;
1633
1634         sdata->reserved_ready = true;
1635
1636         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1637                 if (old_ctx)
1638                         err = ieee80211_vif_use_reserved_reassign(sdata);
1639                 else
1640                         err = ieee80211_vif_use_reserved_assign(sdata);
1641
1642                 if (err)
1643                         return err;
1644         }
1645
1646         /*
1647          * In-place reservation may need to be finalized now either if:
1648          *  a) sdata is taking part in the swapping itself and is the last one
1649          *  b) sdata has switched with a re-assign reservation to an existing
1650          *     context readying in-place switching of old_ctx
1651          *
1652          * In case of (b) do not propagate the error up because the requested
1653          * sdata already switched successfully. Just spill an extra warning.
1654          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1655          * interfaces upon failure.
1656          */
1657         if ((old_ctx &&
1658              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1659             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1660                 err = ieee80211_vif_use_reserved_switch(local);
1661                 if (err && err != -EAGAIN) {
1662                         if (new_ctx->replace_state ==
1663                             IEEE80211_CHANCTX_REPLACES_OTHER)
1664                                 return err;
1665
1666                         wiphy_info(local->hw.wiphy,
1667                                    "depending in-place reservation failed (err=%d)\n",
1668                                    err);
1669                 }
1670         }
1671
1672         return 0;
1673 }
1674
1675 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1676                                    const struct cfg80211_chan_def *chandef,
1677                                    u32 *changed)
1678 {
1679         struct ieee80211_local *local = sdata->local;
1680         struct ieee80211_chanctx_conf *conf;
1681         struct ieee80211_chanctx *ctx;
1682         const struct cfg80211_chan_def *compat;
1683         int ret;
1684
1685         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1686                                      IEEE80211_CHAN_DISABLED))
1687                 return -EINVAL;
1688
1689         mutex_lock(&local->chanctx_mtx);
1690         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1691                 ret = 0;
1692                 goto out;
1693         }
1694
1695         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1696             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1697                 ret = -EINVAL;
1698                 goto out;
1699         }
1700
1701         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1702                                          lockdep_is_held(&local->chanctx_mtx));
1703         if (!conf) {
1704                 ret = -EINVAL;
1705                 goto out;
1706         }
1707
1708         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1709
1710         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1711         if (!compat) {
1712                 ret = -EINVAL;
1713                 goto out;
1714         }
1715
1716         switch (ctx->replace_state) {
1717         case IEEE80211_CHANCTX_REPLACE_NONE:
1718                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1719                         ret = -EBUSY;
1720                         goto out;
1721                 }
1722                 break;
1723         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1724                 /* TODO: Perhaps the bandwidth change could be treated as a
1725                  * reservation itself? */
1726                 ret = -EBUSY;
1727                 goto out;
1728         case IEEE80211_CHANCTX_REPLACES_OTHER:
1729                 /* channel context that is going to replace another channel
1730                  * context doesn't really exist and shouldn't be assigned
1731                  * anywhere yet */
1732                 WARN_ON(1);
1733                 break;
1734         }
1735
1736         ieee80211_vif_update_chandef(sdata, chandef);
1737
1738         ieee80211_recalc_chanctx_chantype(local, ctx);
1739
1740         *changed |= BSS_CHANGED_BANDWIDTH;
1741         ret = 0;
1742  out:
1743         mutex_unlock(&local->chanctx_mtx);
1744         return ret;
1745 }
1746
1747 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1748 {
1749         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1750
1751         lockdep_assert_held(&sdata->local->mtx);
1752
1753         mutex_lock(&sdata->local->chanctx_mtx);
1754         __ieee80211_vif_release_channel(sdata);
1755         mutex_unlock(&sdata->local->chanctx_mtx);
1756 }
1757
1758 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1759 {
1760         struct ieee80211_local *local = sdata->local;
1761         struct ieee80211_sub_if_data *ap;
1762         struct ieee80211_chanctx_conf *conf;
1763
1764         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1765                 return;
1766
1767         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1768
1769         mutex_lock(&local->chanctx_mtx);
1770
1771         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1772                                          lockdep_is_held(&local->chanctx_mtx));
1773         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1774         mutex_unlock(&local->chanctx_mtx);
1775 }
1776
1777 void ieee80211_iter_chan_contexts_atomic(
1778         struct ieee80211_hw *hw,
1779         void (*iter)(struct ieee80211_hw *hw,
1780                      struct ieee80211_chanctx_conf *chanctx_conf,
1781                      void *data),
1782         void *iter_data)
1783 {
1784         struct ieee80211_local *local = hw_to_local(hw);
1785         struct ieee80211_chanctx *ctx;
1786
1787         rcu_read_lock();
1788         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1789                 if (ctx->driver_present)
1790                         iter(hw, &ctx->conf, iter_data);
1791         rcu_read_unlock();
1792 }
1793 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);