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 || !test_sta_flag(sta, WLAN_STA_ASSOC))
 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                 case NL80211_IFTYPE_NAN:
 278                         continue;
 279                 case NL80211_IFTYPE_ADHOC:
 280                 case NL80211_IFTYPE_WDS:
 281                 case NL80211_IFTYPE_MESH_POINT:
 282                 case NL80211_IFTYPE_OCB:
 283                         width = vif->bss_conf.chandef.width;
 284                         break;
 285                 case NL80211_IFTYPE_UNSPECIFIED:
 286                 case NUM_NL80211_IFTYPES:
 287                 case NL80211_IFTYPE_MONITOR:
 288                 case NL80211_IFTYPE_P2P_CLIENT:
 289                 case NL80211_IFTYPE_P2P_GO:
 290                         WARN_ON_ONCE(1);
 291                 }
 292                 max_bw = max(max_bw, width);
 293         }
 294
 295         /* use the configured bandwidth in case of monitor interface */
 296         sdata = rcu_dereference(local->monitor_sdata);
 297         if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
 298                 max_bw = max(max_bw, conf->def.width);
 299
 300         rcu_read_unlock();
 301
 302         return max_bw;
 303 }
 304
 305 /*
 306  * recalc the min required chan width of the channel context, which is
 307  * the max of min required widths of all the interfaces bound to this
 308  * channel context.
 309  */
 310 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
 311                                       struct ieee80211_chanctx *ctx)
 312 {
 313         enum nl80211_chan_width max_bw;
 314         struct cfg80211_chan_def min_def;
 315
 316         lockdep_assert_held(&local->chanctx_mtx);
 317
 318         /* don't optimize 5MHz, 10MHz, and radar_enabled confs */
 319         if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
 320             ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
 321             ctx->conf.radar_enabled) {
 322                 ctx->conf.min_def = ctx->conf.def;
 323                 return;
 324         }
 325
 326         max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
 327
 328         /* downgrade chandef up to max_bw */
 329         min_def = ctx->conf.def;
 330         while (min_def.width > max_bw)
 331                 ieee80211_chandef_downgrade(&min_def);
 332
 333         if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
 334                 return;
 335
 336         ctx->conf.min_def = min_def;
 337         if (!ctx->driver_present)
 338                 return;
 339
 340         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
 341 }
 342
 343 static void ieee80211_change_chanctx(struct ieee80211_local *local,
 344                                      struct ieee80211_chanctx *ctx,
 345                                      const struct cfg80211_chan_def *chandef)
 346 {
 347         if (cfg80211_chandef_identical(&ctx->conf.def, chandef)) {
 348                 ieee80211_recalc_chanctx_min_def(local, ctx);
 349                 return;
 350         }
 351
 352         WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
 353
 354         ctx->conf.def = *chandef;
 355         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
 356         ieee80211_recalc_chanctx_min_def(local, ctx);
 357
 358         if (!local->use_chanctx) {
 359                 local->_oper_chandef = *chandef;
 360                 ieee80211_hw_config(local, 0);
 361         }
 362 }
 363
 364 static struct ieee80211_chanctx *
 365 ieee80211_find_chanctx(struct ieee80211_local *local,
 366                        const struct cfg80211_chan_def *chandef,
 367                        enum ieee80211_chanctx_mode mode)
 368 {
 369         struct ieee80211_chanctx *ctx;
 370
 371         lockdep_assert_held(&local->chanctx_mtx);
 372
 373         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 374                 return NULL;
 375
 376         list_for_each_entry(ctx, &local->chanctx_list, list) {
 377                 const struct cfg80211_chan_def *compat;
 378
 379                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
 380                         continue;
 381
 382                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 383                         continue;
 384
 385                 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
 386                 if (!compat)
 387                         continue;
 388
 389                 compat = ieee80211_chanctx_reserved_chandef(local, ctx,
 390                                                             compat);
 391                 if (!compat)
 392                         continue;
 393
 394                 ieee80211_change_chanctx(local, ctx, compat);
 395
 396                 return ctx;
 397         }
 398
 399         return NULL;
 400 }
 401
 402 bool ieee80211_is_radar_required(struct ieee80211_local *local)
 403 {
 404         struct ieee80211_sub_if_data *sdata;
 405
 406         lockdep_assert_held(&local->mtx);
 407
 408         rcu_read_lock();
 409         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 410                 if (sdata->radar_required) {
 411                         rcu_read_unlock();
 412                         return true;
 413                 }
 414         }
 415         rcu_read_unlock();
 416
 417         return false;
 418 }
 419
 420 static bool
 421 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
 422                                  struct ieee80211_chanctx *ctx)
 423 {
 424         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 425         struct ieee80211_sub_if_data *sdata;
 426         bool required = false;
 427
 428         lockdep_assert_held(&local->chanctx_mtx);
 429         lockdep_assert_held(&local->mtx);
 430
 431         rcu_read_lock();
 432         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 433                 if (!ieee80211_sdata_running(sdata))
 434                         continue;
 435                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 436                         continue;
 437                 if (!sdata->radar_required)
 438                         continue;
 439
 440                 required = true;
 441                 break;
 442         }
 443         rcu_read_unlock();
 444
 445         return required;
 446 }
 447
 448 static struct ieee80211_chanctx *
 449 ieee80211_alloc_chanctx(struct ieee80211_local *local,
 450                         const struct cfg80211_chan_def *chandef,
 451                         enum ieee80211_chanctx_mode mode)
 452 {
 453         struct ieee80211_chanctx *ctx;
 454
 455         lockdep_assert_held(&local->chanctx_mtx);
 456
 457         ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
 458         if (!ctx)
 459                 return NULL;
 460
 461         INIT_LIST_HEAD(&ctx->assigned_vifs);
 462         INIT_LIST_HEAD(&ctx->reserved_vifs);
 463         ctx->conf.def = *chandef;
 464         ctx->conf.rx_chains_static = 1;
 465         ctx->conf.rx_chains_dynamic = 1;
 466         ctx->mode = mode;
 467         ctx->conf.radar_enabled = false;
 468         ieee80211_recalc_chanctx_min_def(local, ctx);
 469
 470         return ctx;
 471 }
 472
 473 static int ieee80211_add_chanctx(struct ieee80211_local *local,
 474                                  struct ieee80211_chanctx *ctx)
 475 {
 476         u32 changed;
 477         int err;
 478
 479         lockdep_assert_held(&local->mtx);
 480         lockdep_assert_held(&local->chanctx_mtx);
 481
 482         if (!local->use_chanctx)
 483                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 484
 485         /* turn idle off *before* setting channel -- some drivers need that */
 486         changed = ieee80211_idle_off(local);
 487         if (changed)
 488                 ieee80211_hw_config(local, changed);
 489
 490         if (!local->use_chanctx) {
 491                 local->_oper_chandef = ctx->conf.def;
 492                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 493         } else {
 494                 err = drv_add_chanctx(local, ctx);
 495                 if (err) {
 496                         ieee80211_recalc_idle(local);
 497                         return err;
 498                 }
 499         }
 500
 501         return 0;
 502 }
 503
 504 static struct ieee80211_chanctx *
 505 ieee80211_new_chanctx(struct ieee80211_local *local,
 506                       const struct cfg80211_chan_def *chandef,
 507                       enum ieee80211_chanctx_mode mode)
 508 {
 509         struct ieee80211_chanctx *ctx;
 510         int err;
 511
 512         lockdep_assert_held(&local->mtx);
 513         lockdep_assert_held(&local->chanctx_mtx);
 514
 515         ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 516         if (!ctx)
 517                 return ERR_PTR(-ENOMEM);
 518
 519         err = ieee80211_add_chanctx(local, ctx);
 520         if (err) {
 521                 kfree(ctx);
 522                 return ERR_PTR(err);
 523         }
 524
 525         list_add_rcu(&ctx->list, &local->chanctx_list);
 526         return ctx;
 527 }
 528
 529 static void ieee80211_del_chanctx(struct ieee80211_local *local,
 530                                   struct ieee80211_chanctx *ctx)
 531 {
 532         lockdep_assert_held(&local->chanctx_mtx);
 533
 534         if (!local->use_chanctx) {
 535                 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
 536                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 537                 chandef->center_freq1 = chandef->chan->center_freq;
 538                 chandef->center_freq2 = 0;
 539
 540                 /* NOTE: Disabling radar is only valid here for
 541                  * single channel context. To be sure, check it ...
 542                  */
 543                 WARN_ON(local->hw.conf.radar_enabled &&
 544                         !list_empty(&local->chanctx_list));
 545
 546                 local->hw.conf.radar_enabled = false;
 547
 548                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 549         } else {
 550                 drv_remove_chanctx(local, ctx);
 551         }
 552
 553         ieee80211_recalc_idle(local);
 554 }
 555
 556 static void ieee80211_free_chanctx(struct ieee80211_local *local,
 557                                    struct ieee80211_chanctx *ctx)
 558 {
 559         lockdep_assert_held(&local->chanctx_mtx);
 560
 561         WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
 562
 563         list_del_rcu(&ctx->list);
 564         ieee80211_del_chanctx(local, ctx);
 565         kfree_rcu(ctx, rcu_head);
 566 }
 567
 568 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 569                                        struct ieee80211_chanctx *ctx)
 570 {
 571         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 572         struct ieee80211_sub_if_data *sdata;
 573         const struct cfg80211_chan_def *compat = NULL;
 574         struct sta_info *sta;
 575
 576         lockdep_assert_held(&local->chanctx_mtx);
 577
 578         rcu_read_lock();
 579         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 580
 581                 if (!ieee80211_sdata_running(sdata))
 582                         continue;
 583                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 584                         continue;
 585                 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 586                         continue;
 587
 588                 if (!compat)
 589                         compat = &sdata->vif.bss_conf.chandef;
 590
 591                 compat = cfg80211_chandef_compatible(
 592                                 &sdata->vif.bss_conf.chandef, compat);
 593                 if (WARN_ON_ONCE(!compat))
 594                         break;
 595         }
 596
 597         /* TDLS peers can sometimes affect the chandef width */
 598         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 599                 if (!sta->uploaded ||
 600                     !test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW) ||
 601                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
 602                     !sta->tdls_chandef.chan)
 603                         continue;
 604
 605                 compat = cfg80211_chandef_compatible(&sta->tdls_chandef,
 606                                                      compat);
 607                 if (WARN_ON_ONCE(!compat))
 608                         break;
 609         }
 610         rcu_read_unlock();
 611
 612         if (!compat)
 613                 return;
 614
 615         ieee80211_change_chanctx(local, ctx, compat);
 616 }
 617
 618 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
 619                                            struct ieee80211_chanctx *chanctx)
 620 {
 621         bool radar_enabled;
 622
 623         lockdep_assert_held(&local->chanctx_mtx);
 624         /* for ieee80211_is_radar_required */
 625         lockdep_assert_held(&local->mtx);
 626
 627         radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
 628
 629         if (radar_enabled == chanctx->conf.radar_enabled)
 630                 return;
 631
 632         chanctx->conf.radar_enabled = radar_enabled;
 633
 634         if (!local->use_chanctx) {
 635                 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
 636                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 637         }
 638
 639         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
 640 }
 641
 642 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 643                                         struct ieee80211_chanctx *new_ctx)
 644 {
 645         struct ieee80211_local *local = sdata->local;
 646         struct ieee80211_chanctx_conf *conf;
 647         struct ieee80211_chanctx *curr_ctx = NULL;
 648         int ret = 0;
 649
 650         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 651                                          lockdep_is_held(&local->chanctx_mtx));
 652
 653         if (conf) {
 654                 curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
 655
 656                 drv_unassign_vif_chanctx(local, sdata, curr_ctx);
 657                 conf = NULL;
 658                 list_del(&sdata->assigned_chanctx_list);
 659         }
 660
 661         if (new_ctx) {
 662                 ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
 663                 if (ret)
 664                         goto out;
 665
 666                 conf = &new_ctx->conf;
 667                 list_add(&sdata->assigned_chanctx_list,
 668                          &new_ctx->assigned_vifs);
 669         }
 670
 671 out:
 672         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
 673
 674         sdata->vif.bss_conf.idle = !conf;
 675
 676         if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
 677                 ieee80211_recalc_chanctx_chantype(local, curr_ctx);
 678                 ieee80211_recalc_smps_chanctx(local, curr_ctx);
 679                 ieee80211_recalc_radar_chanctx(local, curr_ctx);
 680                 ieee80211_recalc_chanctx_min_def(local, curr_ctx);
 681         }
 682
 683         if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
 684                 ieee80211_recalc_txpower(sdata, false);
 685                 ieee80211_recalc_chanctx_min_def(local, new_ctx);
 686         }
 687
 688         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
 689             sdata->vif.type != NL80211_IFTYPE_MONITOR)
 690                 ieee80211_bss_info_change_notify(sdata,
 691                                                  BSS_CHANGED_IDLE);
 692
 693         ieee80211_check_fast_xmit_iface(sdata);
 694
 695         return ret;
 696 }
 697
 698 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 699                                    struct ieee80211_chanctx *chanctx)
 700 {
 701         struct ieee80211_sub_if_data *sdata;
 702         u8 rx_chains_static, rx_chains_dynamic;
 703
 704         lockdep_assert_held(&local->chanctx_mtx);
 705
 706         rx_chains_static = 1;
 707         rx_chains_dynamic = 1;
 708
 709         rcu_read_lock();
 710         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 711                 u8 needed_static, needed_dynamic;
 712
 713                 if (!ieee80211_sdata_running(sdata))
 714                         continue;
 715
 716                 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
 717                                                 &chanctx->conf)
 718                         continue;
 719
 720                 switch (sdata->vif.type) {
 721                 case NL80211_IFTYPE_P2P_DEVICE:
 722                 case NL80211_IFTYPE_NAN:
 723                         continue;
 724                 case NL80211_IFTYPE_STATION:
 725                         if (!sdata->u.mgd.associated)
 726                                 continue;
 727                         break;
 728                 case NL80211_IFTYPE_AP_VLAN:
 729                         continue;
 730                 case NL80211_IFTYPE_AP:
 731                 case NL80211_IFTYPE_ADHOC:
 732                 case NL80211_IFTYPE_WDS:
 733                 case NL80211_IFTYPE_MESH_POINT:
 734                 case NL80211_IFTYPE_OCB:
 735                         break;
 736                 default:
 737                         WARN_ON_ONCE(1);
 738                 }
 739
 740                 switch (sdata->smps_mode) {
 741                 default:
 742                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
 743                                   sdata->smps_mode);
 744                         /* fall through */
 745                 case IEEE80211_SMPS_OFF:
 746                         needed_static = sdata->needed_rx_chains;
 747                         needed_dynamic = sdata->needed_rx_chains;
 748                         break;
 749                 case IEEE80211_SMPS_DYNAMIC:
 750                         needed_static = 1;
 751                         needed_dynamic = sdata->needed_rx_chains;
 752                         break;
 753                 case IEEE80211_SMPS_STATIC:
 754                         needed_static = 1;
 755                         needed_dynamic = 1;
 756                         break;
 757                 }
 758
 759                 rx_chains_static = max(rx_chains_static, needed_static);
 760                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
 761         }
 762
 763         /* Disable SMPS for the monitor interface */
 764         sdata = rcu_dereference(local->monitor_sdata);
 765         if (sdata &&
 766             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
 767                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
 768
 769         rcu_read_unlock();
 770
 771         if (!local->use_chanctx) {
 772                 if (rx_chains_static > 1)
 773                         local->smps_mode = IEEE80211_SMPS_OFF;
 774                 else if (rx_chains_dynamic > 1)
 775                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
 776                 else
 777                         local->smps_mode = IEEE80211_SMPS_STATIC;
 778                 ieee80211_hw_config(local, 0);
 779         }
 780
 781         if (rx_chains_static == chanctx->conf.rx_chains_static &&
 782             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
 783                 return;
 784
 785         chanctx->conf.rx_chains_static = rx_chains_static;
 786         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
 787         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
 788 }
 789
 790 static void
 791 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 792                                       bool clear)
 793 {
 794         struct ieee80211_local *local __maybe_unused = sdata->local;
 795         struct ieee80211_sub_if_data *vlan;
 796         struct ieee80211_chanctx_conf *conf;
 797
 798         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
 799                 return;
 800
 801         lockdep_assert_held(&local->mtx);
 802
 803         /* Check that conf exists, even when clearing this function
 804          * must be called with the AP's channel context still there
 805          * as it would otherwise cause VLANs to have an invalid
 806          * channel context pointer for a while, possibly pointing
 807          * to a channel context that has already been freed.
 808          */
 809         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 810                                          lockdep_is_held(&local->chanctx_mtx));
 811         WARN_ON(!conf);
 812
 813         if (clear)
 814                 conf = NULL;
 815
 816         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 817                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
 818 }
 819
 820 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 821                                          bool clear)
 822 {
 823         struct ieee80211_local *local = sdata->local;
 824
 825         mutex_lock(&local->chanctx_mtx);
 826
 827         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
 828
 829         mutex_unlock(&local->chanctx_mtx);
 830 }
 831
 832 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
 833 {
 834         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
 835
 836         lockdep_assert_held(&sdata->local->chanctx_mtx);
 837
 838         if (WARN_ON(!ctx))
 839                 return -EINVAL;
 840
 841         list_del(&sdata->reserved_chanctx_list);
 842         sdata->reserved_chanctx = NULL;
 843
 844         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
 845                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
 846                         if (WARN_ON(!ctx->replace_ctx))
 847                                 return -EINVAL;
 848
 849                         WARN_ON(ctx->replace_ctx->replace_state !=
 850                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
 851                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
 852
 853                         ctx->replace_ctx->replace_ctx = NULL;
 854                         ctx->replace_ctx->replace_state =
 855                                         IEEE80211_CHANCTX_REPLACE_NONE;
 856
 857                         list_del_rcu(&ctx->list);
 858                         kfree_rcu(ctx, rcu_head);
 859                 } else {
 860                         ieee80211_free_chanctx(sdata->local, ctx);
 861                 }
 862         }
 863
 864         return 0;
 865 }
 866
 867 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
 868                                   const struct cfg80211_chan_def *chandef,
 869                                   enum ieee80211_chanctx_mode mode,
 870                                   bool radar_required)
 871 {
 872         struct ieee80211_local *local = sdata->local;
 873         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
 874
 875         lockdep_assert_held(&local->chanctx_mtx);
 876
 877         curr_ctx = ieee80211_vif_get_chanctx(sdata);
 878         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
 879                 return -ENOTSUPP;
 880
 881         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
 882         if (!new_ctx) {
 883                 if (ieee80211_can_create_new_chanctx(local)) {
 884                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
 885                         if (IS_ERR(new_ctx))
 886                                 return PTR_ERR(new_ctx);
 887                 } else {
 888                         if (!curr_ctx ||
 889                             (curr_ctx->replace_state ==
 890                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 891                             !list_empty(&curr_ctx->reserved_vifs)) {
 892                                 /*
 893                                  * Another vif already requested this context
 894                                  * for a reservation. Find another one hoping
 895                                  * all vifs assigned to it will also switch
 896                                  * soon enough.
 897                                  *
 898                                  * TODO: This needs a little more work as some
 899                                  * cases (more than 2 chanctx capable devices)
 900                                  * may fail which could otherwise succeed
 901                                  * provided some channel context juggling was
 902                                  * performed.
 903                                  *
 904                                  * Consider ctx1..3, vif1..6, each ctx has 2
 905                                  * vifs. vif1 and vif2 from ctx1 request new
 906                                  * different chandefs starting 2 in-place
 907                                  * reserations with ctx4 and ctx5 replacing
 908                                  * ctx1 and ctx2 respectively. Next vif5 and
 909                                  * vif6 from ctx3 reserve ctx4. If vif3 and
 910                                  * vif4 remain on ctx2 as they are then this
 911                                  * fails unless `replace_ctx` from ctx5 is
 912                                  * replaced with ctx3.
 913                                  */
 914                                 list_for_each_entry(ctx, &local->chanctx_list,
 915                                                     list) {
 916                                         if (ctx->replace_state !=
 917                                             IEEE80211_CHANCTX_REPLACE_NONE)
 918                                                 continue;
 919
 920                                         if (!list_empty(&ctx->reserved_vifs))
 921                                                 continue;
 922
 923                                         curr_ctx = ctx;
 924                                         break;
 925                                 }
 926                         }
 927
 928                         /*
 929                          * If that's true then all available contexts already
 930                          * have reservations and cannot be used.
 931                          */
 932                         if (!curr_ctx ||
 933                             (curr_ctx->replace_state ==
 934                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 935                             !list_empty(&curr_ctx->reserved_vifs))
 936                                 return -EBUSY;
 937
 938                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 939                         if (!new_ctx)
 940                                 return -ENOMEM;
 941
 942                         new_ctx->replace_ctx = curr_ctx;
 943                         new_ctx->replace_state =
 944                                         IEEE80211_CHANCTX_REPLACES_OTHER;
 945
 946                         curr_ctx->replace_ctx = new_ctx;
 947                         curr_ctx->replace_state =
 948                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
 949
 950                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
 951                 }
 952         }
 953
 954         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
 955         sdata->reserved_chanctx = new_ctx;
 956         sdata->reserved_chandef = *chandef;
 957         sdata->reserved_radar_required = radar_required;
 958         sdata->reserved_ready = false;
 959
 960         return 0;
 961 }
 962
 963 static void
 964 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
 965 {
 966         switch (sdata->vif.type) {
 967         case NL80211_IFTYPE_ADHOC:
 968         case NL80211_IFTYPE_AP:
 969         case NL80211_IFTYPE_MESH_POINT:
 970         case NL80211_IFTYPE_OCB:
 971                 ieee80211_queue_work(&sdata->local->hw,
 972                                      &sdata->csa_finalize_work);
 973                 break;
 974         case NL80211_IFTYPE_STATION:
 975                 ieee80211_queue_work(&sdata->local->hw,
 976                                      &sdata->u.mgd.chswitch_work);
 977                 break;
 978         case NL80211_IFTYPE_UNSPECIFIED:
 979         case NL80211_IFTYPE_AP_VLAN:
 980         case NL80211_IFTYPE_WDS:
 981         case NL80211_IFTYPE_MONITOR:
 982         case NL80211_IFTYPE_P2P_CLIENT:
 983         case NL80211_IFTYPE_P2P_GO:
 984         case NL80211_IFTYPE_P2P_DEVICE:
 985         case NL80211_IFTYPE_NAN:
 986         case NUM_NL80211_IFTYPES:
 987                 WARN_ON(1);
 988                 break;
 989         }
 990 }
 991
 992 static void
 993 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
 994                              const struct cfg80211_chan_def *chandef)
 995 {
 996         struct ieee80211_sub_if_data *vlan;
 997
 998         sdata->vif.bss_conf.chandef = *chandef;
 999
1000         if (sdata->vif.type != NL80211_IFTYPE_AP)
1001                 return;
1002
1003         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1004                 vlan->vif.bss_conf.chandef = *chandef;
1005 }
1006
1007 static int
1008 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
1009 {
1010         struct ieee80211_local *local = sdata->local;
1011         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1012         struct ieee80211_chanctx *old_ctx, *new_ctx;
1013         const struct cfg80211_chan_def *chandef;
1014         u32 changed = 0;
1015         int err;
1016
1017         lockdep_assert_held(&local->mtx);
1018         lockdep_assert_held(&local->chanctx_mtx);
1019
1020         new_ctx = sdata->reserved_chanctx;
1021         old_ctx = ieee80211_vif_get_chanctx(sdata);
1022
1023         if (WARN_ON(!sdata->reserved_ready))
1024                 return -EBUSY;
1025
1026         if (WARN_ON(!new_ctx))
1027                 return -EINVAL;
1028
1029         if (WARN_ON(!old_ctx))
1030                 return -EINVAL;
1031
1032         if (WARN_ON(new_ctx->replace_state ==
1033                     IEEE80211_CHANCTX_REPLACES_OTHER))
1034                 return -EINVAL;
1035
1036         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1037                                 &sdata->reserved_chandef);
1038         if (WARN_ON(!chandef))
1039                 return -EINVAL;
1040
1041         ieee80211_change_chanctx(local, new_ctx, chandef);
1042
1043         vif_chsw[0].vif = &sdata->vif;
1044         vif_chsw[0].old_ctx = &old_ctx->conf;
1045         vif_chsw[0].new_ctx = &new_ctx->conf;
1046
1047         list_del(&sdata->reserved_chanctx_list);
1048         sdata->reserved_chanctx = NULL;
1049
1050         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1051                                      CHANCTX_SWMODE_REASSIGN_VIF);
1052         if (err) {
1053                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1054                         ieee80211_free_chanctx(local, new_ctx);
1055
1056                 goto out;
1057         }
1058
1059         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1060         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1061
1062         if (sdata->vif.type == NL80211_IFTYPE_AP)
1063                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1064
1065         ieee80211_check_fast_xmit_iface(sdata);
1066
1067         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1068                 ieee80211_free_chanctx(local, old_ctx);
1069
1070         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1071                 changed = BSS_CHANGED_BANDWIDTH;
1072
1073         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1074
1075         ieee80211_recalc_smps_chanctx(local, new_ctx);
1076         ieee80211_recalc_radar_chanctx(local, new_ctx);
1077         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1078
1079         if (changed)
1080                 ieee80211_bss_info_change_notify(sdata, changed);
1081
1082 out:
1083         ieee80211_vif_chanctx_reservation_complete(sdata);
1084         return err;
1085 }
1086
1087 static int
1088 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1089 {
1090         struct ieee80211_local *local = sdata->local;
1091         struct ieee80211_chanctx *old_ctx, *new_ctx;
1092         const struct cfg80211_chan_def *chandef;
1093         int err;
1094
1095         old_ctx = ieee80211_vif_get_chanctx(sdata);
1096         new_ctx = sdata->reserved_chanctx;
1097
1098         if (WARN_ON(!sdata->reserved_ready))
1099                 return -EINVAL;
1100
1101         if (WARN_ON(old_ctx))
1102                 return -EINVAL;
1103
1104         if (WARN_ON(!new_ctx))
1105                 return -EINVAL;
1106
1107         if (WARN_ON(new_ctx->replace_state ==
1108                     IEEE80211_CHANCTX_REPLACES_OTHER))
1109                 return -EINVAL;
1110
1111         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1112                                 &sdata->reserved_chandef);
1113         if (WARN_ON(!chandef))
1114                 return -EINVAL;
1115
1116         ieee80211_change_chanctx(local, new_ctx, chandef);
1117
1118         list_del(&sdata->reserved_chanctx_list);
1119         sdata->reserved_chanctx = NULL;
1120
1121         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1122         if (err) {
1123                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1124                         ieee80211_free_chanctx(local, new_ctx);
1125
1126                 goto out;
1127         }
1128
1129 out:
1130         ieee80211_vif_chanctx_reservation_complete(sdata);
1131         return err;
1132 }
1133
1134 static bool
1135 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1136 {
1137         struct ieee80211_chanctx *old_ctx, *new_ctx;
1138
1139         lockdep_assert_held(&sdata->local->chanctx_mtx);
1140
1141         new_ctx = sdata->reserved_chanctx;
1142         old_ctx = ieee80211_vif_get_chanctx(sdata);
1143
1144         if (!old_ctx)
1145                 return false;
1146
1147         if (WARN_ON(!new_ctx))
1148                 return false;
1149
1150         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1151                 return false;
1152
1153         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1154                 return false;
1155
1156         return true;
1157 }
1158
1159 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1160                                         struct ieee80211_chanctx *new_ctx)
1161 {
1162         const struct cfg80211_chan_def *chandef;
1163
1164         lockdep_assert_held(&local->mtx);
1165         lockdep_assert_held(&local->chanctx_mtx);
1166
1167         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1168         if (WARN_ON(!chandef))
1169                 return -EINVAL;
1170
1171         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1172         local->_oper_chandef = *chandef;
1173         ieee80211_hw_config(local, 0);
1174
1175         return 0;
1176 }
1177
1178 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1179                                       int n_vifs)
1180 {
1181         struct ieee80211_vif_chanctx_switch *vif_chsw;
1182         struct ieee80211_sub_if_data *sdata;
1183         struct ieee80211_chanctx *ctx, *old_ctx;
1184         int i, err;
1185
1186         lockdep_assert_held(&local->mtx);
1187         lockdep_assert_held(&local->chanctx_mtx);
1188
1189         vif_chsw = kzalloc(sizeof(vif_chsw[0]) * n_vifs, GFP_KERNEL);
1190         if (!vif_chsw)
1191                 return -ENOMEM;
1192
1193         i = 0;
1194         list_for_each_entry(ctx, &local->chanctx_list, list) {
1195                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1196                         continue;
1197
1198                 if (WARN_ON(!ctx->replace_ctx)) {
1199                         err = -EINVAL;
1200                         goto out;
1201                 }
1202
1203                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1204                                     reserved_chanctx_list) {
1205                         if (!ieee80211_vif_has_in_place_reservation(
1206                                         sdata))
1207                                 continue;
1208
1209                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1210                         vif_chsw[i].vif = &sdata->vif;
1211                         vif_chsw[i].old_ctx = &old_ctx->conf;
1212                         vif_chsw[i].new_ctx = &ctx->conf;
1213
1214                         i++;
1215                 }
1216         }
1217
1218         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1219                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1220
1221 out:
1222         kfree(vif_chsw);
1223         return err;
1224 }
1225
1226 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1227 {
1228         struct ieee80211_chanctx *ctx;
1229         int err;
1230
1231         lockdep_assert_held(&local->mtx);
1232         lockdep_assert_held(&local->chanctx_mtx);
1233
1234         list_for_each_entry(ctx, &local->chanctx_list, list) {
1235                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1236                         continue;
1237
1238                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1239                         continue;
1240
1241                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1242                 err = ieee80211_add_chanctx(local, ctx);
1243                 if (err)
1244                         goto err;
1245         }
1246
1247         return 0;
1248
1249 err:
1250         WARN_ON(ieee80211_add_chanctx(local, ctx));
1251         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1252                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1253                         continue;
1254
1255                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1256                         continue;
1257
1258                 ieee80211_del_chanctx(local, ctx);
1259                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1260         }
1261
1262         return err;
1263 }
1264
1265 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1266 {
1267         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1268         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1269         struct ieee80211_chanctx *new_ctx = NULL;
1270         int i, err, n_assigned, n_reserved, n_ready;
1271         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1272
1273         lockdep_assert_held(&local->mtx);
1274         lockdep_assert_held(&local->chanctx_mtx);
1275
1276         /*
1277          * If there are 2 independent pairs of channel contexts performing
1278          * cross-switch of their vifs this code will still wait until both are
1279          * ready even though it could be possible to switch one before the
1280          * other is ready.
1281          *
1282          * For practical reasons and code simplicity just do a single huge
1283          * switch.
1284          */
1285
1286         /*
1287          * Verify if the reservation is still feasible.
1288          *  - if it's not then disconnect
1289          *  - if it is but not all vifs necessary are ready then defer
1290          */
1291
1292         list_for_each_entry(ctx, &local->chanctx_list, list) {
1293                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1294                         continue;
1295
1296                 if (WARN_ON(!ctx->replace_ctx)) {
1297                         err = -EINVAL;
1298                         goto err;
1299                 }
1300
1301                 if (!local->use_chanctx)
1302                         new_ctx = ctx;
1303
1304                 n_ctx++;
1305
1306                 n_assigned = 0;
1307                 n_reserved = 0;
1308                 n_ready = 0;
1309
1310                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1311                                     assigned_chanctx_list) {
1312                         n_assigned++;
1313                         if (sdata->reserved_chanctx) {
1314                                 n_reserved++;
1315                                 if (sdata->reserved_ready)
1316                                         n_ready++;
1317                         }
1318                 }
1319
1320                 if (n_assigned != n_reserved) {
1321                         if (n_ready == n_reserved) {
1322                                 wiphy_info(local->hw.wiphy,
1323                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1324                                 err = -EBUSY;
1325                                 goto err;
1326                         }
1327
1328                         return -EAGAIN;
1329                 }
1330
1331                 ctx->conf.radar_enabled = false;
1332                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1333                                     reserved_chanctx_list) {
1334                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1335                             !sdata->reserved_ready)
1336                                 return -EAGAIN;
1337
1338                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1339                         if (old_ctx) {
1340                                 if (old_ctx->replace_state ==
1341                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1342                                         n_vifs_switch++;
1343                                 else
1344                                         n_vifs_assign++;
1345                         } else {
1346                                 n_vifs_ctxless++;
1347                         }
1348
1349                         if (sdata->reserved_radar_required)
1350                                 ctx->conf.radar_enabled = true;
1351                 }
1352         }
1353
1354         if (WARN_ON(n_ctx == 0) ||
1355             WARN_ON(n_vifs_switch == 0 &&
1356                     n_vifs_assign == 0 &&
1357                     n_vifs_ctxless == 0) ||
1358             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1359             WARN_ON(!new_ctx && !local->use_chanctx)) {
1360                 err = -EINVAL;
1361                 goto err;
1362         }
1363
1364         /*
1365          * All necessary vifs are ready. Perform the switch now depending on
1366          * reservations and driver capabilities.
1367          */
1368
1369         if (local->use_chanctx) {
1370                 if (n_vifs_switch > 0) {
1371                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1372                         if (err)
1373                                 goto err;
1374                 }
1375
1376                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1377                         err = ieee80211_chsw_switch_ctxs(local);
1378                         if (err)
1379                                 goto err;
1380                 }
1381         } else {
1382                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1383                 if (err)
1384                         goto err;
1385         }
1386
1387         /*
1388          * Update all structures, values and pointers to point to new channel
1389          * context(s).
1390          */
1391
1392         i = 0;
1393         list_for_each_entry(ctx, &local->chanctx_list, list) {
1394                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1395                         continue;
1396
1397                 if (WARN_ON(!ctx->replace_ctx)) {
1398                         err = -EINVAL;
1399                         goto err;
1400                 }
1401
1402                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1403                                     reserved_chanctx_list) {
1404                         u32 changed = 0;
1405
1406                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1407                                 continue;
1408
1409                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1410
1411                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1412                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1413                                                                       false);
1414
1415                         ieee80211_check_fast_xmit_iface(sdata);
1416
1417                         sdata->radar_required = sdata->reserved_radar_required;
1418
1419                         if (sdata->vif.bss_conf.chandef.width !=
1420                             sdata->reserved_chandef.width)
1421                                 changed = BSS_CHANGED_BANDWIDTH;
1422
1423                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1424                         if (changed)
1425                                 ieee80211_bss_info_change_notify(sdata,
1426                                                                  changed);
1427
1428                         ieee80211_recalc_txpower(sdata, false);
1429                 }
1430
1431                 ieee80211_recalc_chanctx_chantype(local, ctx);
1432                 ieee80211_recalc_smps_chanctx(local, ctx);
1433                 ieee80211_recalc_radar_chanctx(local, ctx);
1434                 ieee80211_recalc_chanctx_min_def(local, ctx);
1435
1436                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1437                                          reserved_chanctx_list) {
1438                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1439                                 continue;
1440
1441                         list_del(&sdata->reserved_chanctx_list);
1442                         list_move(&sdata->assigned_chanctx_list,
1443                                   &ctx->assigned_vifs);
1444                         sdata->reserved_chanctx = NULL;
1445
1446                         ieee80211_vif_chanctx_reservation_complete(sdata);
1447                 }
1448
1449                 /*
1450                  * This context might have been a dependency for an already
1451                  * ready re-assign reservation interface that was deferred. Do
1452                  * not propagate error to the caller though. The in-place
1453                  * reservation for originally requested interface has already
1454                  * succeeded at this point.
1455                  */
1456                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1457                                          reserved_chanctx_list) {
1458                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1459                                         sdata)))
1460                                 continue;
1461
1462                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1463                                 continue;
1464
1465                         if (!sdata->reserved_ready)
1466                                 continue;
1467
1468                         if (ieee80211_vif_get_chanctx(sdata))
1469                                 err = ieee80211_vif_use_reserved_reassign(
1470                                                 sdata);
1471                         else
1472                                 err = ieee80211_vif_use_reserved_assign(sdata);
1473
1474                         if (err) {
1475                                 sdata_info(sdata,
1476                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1477                                            err);
1478                                 ieee80211_vif_unreserve_chanctx(sdata);
1479                                 cfg80211_stop_iface(local->hw.wiphy,
1480                                                     &sdata->wdev,
1481                                                     GFP_KERNEL);
1482                         }
1483                 }
1484         }
1485
1486         /*
1487          * Finally free old contexts
1488          */
1489
1490         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1491                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1492                         continue;
1493
1494                 ctx->replace_ctx->replace_ctx = NULL;
1495                 ctx->replace_ctx->replace_state =
1496                                 IEEE80211_CHANCTX_REPLACE_NONE;
1497
1498                 list_del_rcu(&ctx->list);
1499                 kfree_rcu(ctx, rcu_head);
1500         }
1501
1502         return 0;
1503
1504 err:
1505         list_for_each_entry(ctx, &local->chanctx_list, list) {
1506                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1507                         continue;
1508
1509                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1510                                          reserved_chanctx_list) {
1511                         ieee80211_vif_unreserve_chanctx(sdata);
1512                         ieee80211_vif_chanctx_reservation_complete(sdata);
1513                 }
1514         }
1515
1516         return err;
1517 }
1518
1519 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1520 {
1521         struct ieee80211_local *local = sdata->local;
1522         struct ieee80211_chanctx_conf *conf;
1523         struct ieee80211_chanctx *ctx;
1524         bool use_reserved_switch = false;
1525
1526         lockdep_assert_held(&local->chanctx_mtx);
1527
1528         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1529                                          lockdep_is_held(&local->chanctx_mtx));
1530         if (!conf)
1531                 return;
1532
1533         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1534
1535         if (sdata->reserved_chanctx) {
1536                 if (sdata->reserved_chanctx->replace_state ==
1537                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1538                     ieee80211_chanctx_num_reserved(local,
1539                                                    sdata->reserved_chanctx) > 1)
1540                         use_reserved_switch = true;
1541
1542                 ieee80211_vif_unreserve_chanctx(sdata);
1543         }
1544
1545         ieee80211_assign_vif_chanctx(sdata, NULL);
1546         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1547                 ieee80211_free_chanctx(local, ctx);
1548
1549         sdata->radar_required = false;
1550
1551         /* Unreserving may ready an in-place reservation. */
1552         if (use_reserved_switch)
1553                 ieee80211_vif_use_reserved_switch(local);
1554 }
1555
1556 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1557                               const struct cfg80211_chan_def *chandef,
1558                               enum ieee80211_chanctx_mode mode)
1559 {
1560         struct ieee80211_local *local = sdata->local;
1561         struct ieee80211_chanctx *ctx;
1562         u8 radar_detect_width = 0;
1563         int ret;
1564
1565         lockdep_assert_held(&local->mtx);
1566
1567         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1568
1569         mutex_lock(&local->chanctx_mtx);
1570
1571         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1572                                             chandef,
1573                                             sdata->wdev.iftype);
1574         if (ret < 0)
1575                 goto out;
1576         if (ret > 0)
1577                 radar_detect_width = BIT(chandef->width);
1578
1579         sdata->radar_required = ret;
1580
1581         ret = ieee80211_check_combinations(sdata, chandef, mode,
1582                                            radar_detect_width);
1583         if (ret < 0)
1584                 goto out;
1585
1586         __ieee80211_vif_release_channel(sdata);
1587
1588         ctx = ieee80211_find_chanctx(local, chandef, mode);
1589         if (!ctx)
1590                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1591         if (IS_ERR(ctx)) {
1592                 ret = PTR_ERR(ctx);
1593                 goto out;
1594         }
1595
1596         ieee80211_vif_update_chandef(sdata, chandef);
1597
1598         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1599         if (ret) {
1600                 /* if assign fails refcount stays the same */
1601                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1602                         ieee80211_free_chanctx(local, ctx);
1603                 goto out;
1604         }
1605
1606         ieee80211_recalc_smps_chanctx(local, ctx);
1607         ieee80211_recalc_radar_chanctx(local, ctx);
1608  out:
1609         if (ret)
1610                 sdata->radar_required = false;
1611
1612         mutex_unlock(&local->chanctx_mtx);
1613         return ret;
1614 }
1615
1616 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1617 {
1618         struct ieee80211_local *local = sdata->local;
1619         struct ieee80211_chanctx *new_ctx;
1620         struct ieee80211_chanctx *old_ctx;
1621         int err;
1622
1623         lockdep_assert_held(&local->mtx);
1624         lockdep_assert_held(&local->chanctx_mtx);
1625
1626         new_ctx = sdata->reserved_chanctx;
1627         old_ctx = ieee80211_vif_get_chanctx(sdata);
1628
1629         if (WARN_ON(!new_ctx))
1630                 return -EINVAL;
1631
1632         if (WARN_ON(new_ctx->replace_state ==
1633                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1634                 return -EINVAL;
1635
1636         if (WARN_ON(sdata->reserved_ready))
1637                 return -EINVAL;
1638
1639         sdata->reserved_ready = true;
1640
1641         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1642                 if (old_ctx)
1643                         err = ieee80211_vif_use_reserved_reassign(sdata);
1644                 else
1645                         err = ieee80211_vif_use_reserved_assign(sdata);
1646
1647                 if (err)
1648                         return err;
1649         }
1650
1651         /*
1652          * In-place reservation may need to be finalized now either if:
1653          *  a) sdata is taking part in the swapping itself and is the last one
1654          *  b) sdata has switched with a re-assign reservation to an existing
1655          *     context readying in-place switching of old_ctx
1656          *
1657          * In case of (b) do not propagate the error up because the requested
1658          * sdata already switched successfully. Just spill an extra warning.
1659          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1660          * interfaces upon failure.
1661          */
1662         if ((old_ctx &&
1663              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1664             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1665                 err = ieee80211_vif_use_reserved_switch(local);
1666                 if (err && err != -EAGAIN) {
1667                         if (new_ctx->replace_state ==
1668                             IEEE80211_CHANCTX_REPLACES_OTHER)
1669                                 return err;
1670
1671                         wiphy_info(local->hw.wiphy,
1672                                    "depending in-place reservation failed (err=%d)\n",
1673                                    err);
1674                 }
1675         }
1676
1677         return 0;
1678 }
1679
1680 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1681                                    const struct cfg80211_chan_def *chandef,
1682                                    u32 *changed)
1683 {
1684         struct ieee80211_local *local = sdata->local;
1685         struct ieee80211_chanctx_conf *conf;
1686         struct ieee80211_chanctx *ctx;
1687         const struct cfg80211_chan_def *compat;
1688         int ret;
1689
1690         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1691                                      IEEE80211_CHAN_DISABLED))
1692                 return -EINVAL;
1693
1694         mutex_lock(&local->chanctx_mtx);
1695         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1696                 ret = 0;
1697                 goto out;
1698         }
1699
1700         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1701             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1702                 ret = -EINVAL;
1703                 goto out;
1704         }
1705
1706         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1707                                          lockdep_is_held(&local->chanctx_mtx));
1708         if (!conf) {
1709                 ret = -EINVAL;
1710                 goto out;
1711         }
1712
1713         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1714
1715         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1716         if (!compat) {
1717                 ret = -EINVAL;
1718                 goto out;
1719         }
1720
1721         switch (ctx->replace_state) {
1722         case IEEE80211_CHANCTX_REPLACE_NONE:
1723                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1724                         ret = -EBUSY;
1725                         goto out;
1726                 }
1727                 break;
1728         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1729                 /* TODO: Perhaps the bandwidth change could be treated as a
1730                  * reservation itself? */
1731                 ret = -EBUSY;
1732                 goto out;
1733         case IEEE80211_CHANCTX_REPLACES_OTHER:
1734                 /* channel context that is going to replace another channel
1735                  * context doesn't really exist and shouldn't be assigned
1736                  * anywhere yet */
1737                 WARN_ON(1);
1738                 break;
1739         }
1740
1741         ieee80211_vif_update_chandef(sdata, chandef);
1742
1743         ieee80211_recalc_chanctx_chantype(local, ctx);
1744
1745         *changed |= BSS_CHANGED_BANDWIDTH;
1746         ret = 0;
1747  out:
1748         mutex_unlock(&local->chanctx_mtx);
1749         return ret;
1750 }
1751
1752 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1753 {
1754         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1755
1756         lockdep_assert_held(&sdata->local->mtx);
1757
1758         mutex_lock(&sdata->local->chanctx_mtx);
1759         __ieee80211_vif_release_channel(sdata);
1760         mutex_unlock(&sdata->local->chanctx_mtx);
1761 }
1762
1763 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1764 {
1765         struct ieee80211_local *local = sdata->local;
1766         struct ieee80211_sub_if_data *ap;
1767         struct ieee80211_chanctx_conf *conf;
1768
1769         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1770                 return;
1771
1772         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1773
1774         mutex_lock(&local->chanctx_mtx);
1775
1776         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1777                                          lockdep_is_held(&local->chanctx_mtx));
1778         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1779         mutex_unlock(&local->chanctx_mtx);
1780 }
1781
1782 void ieee80211_iter_chan_contexts_atomic(
1783         struct ieee80211_hw *hw,
1784         void (*iter)(struct ieee80211_hw *hw,
1785                      struct ieee80211_chanctx_conf *chanctx_conf,
1786                      void *data),
1787         void *iter_data)
1788 {
1789         struct ieee80211_local *local = hw_to_local(hw);
1790         struct ieee80211_chanctx *ctx;
1791
1792         rcu_read_lock();
1793         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1794                 if (ctx->driver_present)
1795                         iter(hw, &ctx->conf, iter_data);
1796         rcu_read_unlock();
1797 }
1798 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);