net/mac80211/chan.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * mac80211 - channel management
   4  */
   5
   6 #include <linux/nl80211.h>
   7 #include <linux/export.h>
   8 #include <linux/rtnetlink.h>
   9 #include <net/cfg80211.h>
  10 #include "ieee80211_i.h"
  11 #include "driver-ops.h"
  12
  13 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
  14                                           struct ieee80211_chanctx *ctx)
  15 {
  16         struct ieee80211_sub_if_data *sdata;
  17         int num = 0;
  18
  19         lockdep_assert_held(&local->chanctx_mtx);
  20
  21         list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
  22                 num++;
  23
  24         return num;
  25 }
  26
  27 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
  28                                           struct ieee80211_chanctx *ctx)
  29 {
  30         struct ieee80211_sub_if_data *sdata;
  31         int num = 0;
  32
  33         lockdep_assert_held(&local->chanctx_mtx);
  34
  35         list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
  36                 num++;
  37
  38         return num;
  39 }
  40
  41 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
  42                                struct ieee80211_chanctx *ctx)
  43 {
  44         return ieee80211_chanctx_num_assigned(local, ctx) +
  45                ieee80211_chanctx_num_reserved(local, ctx);
  46 }
  47
  48 static int ieee80211_num_chanctx(struct ieee80211_local *local)
  49 {
  50         struct ieee80211_chanctx *ctx;
  51         int num = 0;
  52
  53         lockdep_assert_held(&local->chanctx_mtx);
  54
  55         list_for_each_entry(ctx, &local->chanctx_list, list)
  56                 num++;
  57
  58         return num;
  59 }
  60
  61 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
  62 {
  63         lockdep_assert_held(&local->chanctx_mtx);
  64         return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
  65 }
  66
  67 static struct ieee80211_chanctx *
  68 ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
  69 {
  70         struct ieee80211_local *local __maybe_unused = sdata->local;
  71         struct ieee80211_chanctx_conf *conf;
  72
  73         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
  74                                          lockdep_is_held(&local->chanctx_mtx));
  75         if (!conf)
  76                 return NULL;
  77
  78         return container_of(conf, struct ieee80211_chanctx, conf);
  79 }
  80
  81 static const struct cfg80211_chan_def *
  82 ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
  83                                    struct ieee80211_chanctx *ctx,
  84                                    const struct cfg80211_chan_def *compat)
  85 {
  86         struct ieee80211_sub_if_data *sdata;
  87
  88         lockdep_assert_held(&local->chanctx_mtx);
  89
  90         list_for_each_entry(sdata, &ctx->reserved_vifs,
  91                             reserved_chanctx_list) {
  92                 if (!compat)
  93                         compat = &sdata->reserved_chandef;
  94
  95                 compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
  96                                                      compat);
  97                 if (!compat)
  98                         break;
  99         }
 100
 101         return compat;
 102 }
 103
 104 static const struct cfg80211_chan_def *
 105 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
 106                                        struct ieee80211_chanctx *ctx,
 107                                        const struct cfg80211_chan_def *compat)
 108 {
 109         struct ieee80211_sub_if_data *sdata;
 110
 111         lockdep_assert_held(&local->chanctx_mtx);
 112
 113         list_for_each_entry(sdata, &ctx->assigned_vifs,
 114                             assigned_chanctx_list) {
 115                 if (sdata->reserved_chanctx != NULL)
 116                         continue;
 117
 118                 if (!compat)
 119                         compat = &sdata->vif.bss_conf.chandef;
 120
 121                 compat = cfg80211_chandef_compatible(
 122                                 &sdata->vif.bss_conf.chandef, compat);
 123                 if (!compat)
 124                         break;
 125         }
 126
 127         return compat;
 128 }
 129
 130 static const struct cfg80211_chan_def *
 131 ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
 132                                    struct ieee80211_chanctx *ctx,
 133                                    const struct cfg80211_chan_def *compat)
 134 {
 135         lockdep_assert_held(&local->chanctx_mtx);
 136
 137         compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
 138         if (!compat)
 139                 return NULL;
 140
 141         compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
 142         if (!compat)
 143                 return NULL;
 144
 145         return compat;
 146 }
 147
 148 static bool
 149 ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
 150                                       struct ieee80211_chanctx *ctx,
 151                                       const struct cfg80211_chan_def *def)
 152 {
 153         lockdep_assert_held(&local->chanctx_mtx);
 154
 155         if (ieee80211_chanctx_combined_chandef(local, ctx, def))
 156                 return true;
 157
 158         if (!list_empty(&ctx->reserved_vifs) &&
 159             ieee80211_chanctx_reserved_chandef(local, ctx, def))
 160                 return true;
 161
 162         return false;
 163 }
 164
 165 static struct ieee80211_chanctx *
 166 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
 167                                    const struct cfg80211_chan_def *chandef,
 168                                    enum ieee80211_chanctx_mode mode)
 169 {
 170         struct ieee80211_chanctx *ctx;
 171
 172         lockdep_assert_held(&local->chanctx_mtx);
 173
 174         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 175                 return NULL;
 176
 177         list_for_each_entry(ctx, &local->chanctx_list, list) {
 178                 if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
 179                         continue;
 180
 181                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 182                         continue;
 183
 184                 if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
 185                                                            chandef))
 186                         continue;
 187
 188                 return ctx;
 189         }
 190
 191         return NULL;
 192 }
 193
 194 enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
 195 {
 196         switch (sta->bandwidth) {
 197         case IEEE80211_STA_RX_BW_20:
 198                 if (sta->ht_cap.ht_supported)
 199                         return NL80211_CHAN_WIDTH_20;
 200                 else
 201                         return NL80211_CHAN_WIDTH_20_NOHT;
 202         case IEEE80211_STA_RX_BW_40:
 203                 return NL80211_CHAN_WIDTH_40;
 204         case IEEE80211_STA_RX_BW_80:
 205                 return NL80211_CHAN_WIDTH_80;
 206         case IEEE80211_STA_RX_BW_160:
 207                 /*
 208                  * This applied for both 160 and 80+80. since we use
 209                  * the returned value to consider degradation of
 210                  * ctx->conf.min_def, we have to make sure to take
 211                  * the bigger one (NL80211_CHAN_WIDTH_160).
 212                  * Otherwise we might try degrading even when not
 213                  * needed, as the max required sta_bw returned (80+80)
 214                  * might be smaller than the configured bw (160).
 215                  */
 216                 return NL80211_CHAN_WIDTH_160;
 217         default:
 218                 WARN_ON(1);
 219                 return NL80211_CHAN_WIDTH_20;
 220         }
 221 }
 222
 223 static enum nl80211_chan_width
 224 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
 225 {
 226         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 227         struct sta_info *sta;
 228
 229         rcu_read_lock();
 230         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
 231                 if (sdata != sta->sdata &&
 232                     !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
 233                         continue;
 234
 235                 max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
 236         }
 237         rcu_read_unlock();
 238
 239         return max_bw;
 240 }
 241
 242 static enum nl80211_chan_width
 243 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
 244                                       struct ieee80211_chanctx_conf *conf)
 245 {
 246         struct ieee80211_sub_if_data *sdata;
 247         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 248
 249         rcu_read_lock();
 250         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 251                 struct ieee80211_vif *vif = &sdata->vif;
 252                 enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
 253
 254                 if (!ieee80211_sdata_running(sdata))
 255                         continue;
 256
 257                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 258                         continue;
 259
 260                 switch (vif->type) {
 261                 case NL80211_IFTYPE_AP:
 262                 case NL80211_IFTYPE_AP_VLAN:
 263                         width = ieee80211_get_max_required_bw(sdata);
 264                         break;
 265                 case NL80211_IFTYPE_STATION:
 266                         /*
 267                          * The ap's sta->bandwidth is not set yet at this
 268                          * point, so take the width from the chandef, but
 269                          * account also for TDLS peers
 270                          */
 271                         width = max(vif->bss_conf.chandef.width,
 272                                     ieee80211_get_max_required_bw(sdata));
 273                         break;
 274                 case NL80211_IFTYPE_P2P_DEVICE:
 275                 case NL80211_IFTYPE_NAN:
 276                         continue;
 277                 case NL80211_IFTYPE_ADHOC:
 278                 case NL80211_IFTYPE_WDS:
 279                 case NL80211_IFTYPE_MESH_POINT:
 280                 case NL80211_IFTYPE_OCB:
 281                         width = vif->bss_conf.chandef.width;
 282                         break;
 283                 case NL80211_IFTYPE_UNSPECIFIED:
 284                 case NUM_NL80211_IFTYPES:
 285                 case NL80211_IFTYPE_MONITOR:
 286                 case NL80211_IFTYPE_P2P_CLIENT:
 287                 case NL80211_IFTYPE_P2P_GO:
 288                         WARN_ON_ONCE(1);
 289                 }
 290                 max_bw = max(max_bw, width);
 291         }
 292
 293         /* use the configured bandwidth in case of monitor interface */
 294         sdata = rcu_dereference(local->monitor_sdata);
 295         if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
 296                 max_bw = max(max_bw, conf->def.width);
 297
 298         rcu_read_unlock();
 299
 300         return max_bw;
 301 }
 302
 303 /*
 304  * recalc the min required chan width of the channel context, which is
 305  * the max of min required widths of all the interfaces bound to this
 306  * channel context.
 307  */
 308 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
 309                                       struct ieee80211_chanctx *ctx)
 310 {
 311         enum nl80211_chan_width max_bw;
 312         struct cfg80211_chan_def min_def;
 313
 314         lockdep_assert_held(&local->chanctx_mtx);
 315
 316         /* don't optimize non-20MHz based and radar_enabled confs */
 317         if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
 318             ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
 319             ctx->conf.def.width == NL80211_CHAN_WIDTH_1 ||
 320             ctx->conf.def.width == NL80211_CHAN_WIDTH_2 ||
 321             ctx->conf.def.width == NL80211_CHAN_WIDTH_4 ||
 322             ctx->conf.def.width == NL80211_CHAN_WIDTH_8 ||
 323             ctx->conf.def.width == NL80211_CHAN_WIDTH_16 ||
 324             ctx->conf.radar_enabled) {
 325                 ctx->conf.min_def = ctx->conf.def;
 326                 return;
 327         }
 328
 329         max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
 330
 331         /* downgrade chandef up to max_bw */
 332         min_def = ctx->conf.def;
 333         while (min_def.width > max_bw)
 334                 ieee80211_chandef_downgrade(&min_def);
 335
 336         if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
 337                 return;
 338
 339         ctx->conf.min_def = min_def;
 340         if (!ctx->driver_present)
 341                 return;
 342
 343         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
 344 }
 345
 346 static void ieee80211_change_chanctx(struct ieee80211_local *local,
 347                                      struct ieee80211_chanctx *ctx,
 348                                      const struct cfg80211_chan_def *chandef)
 349 {
 350         if (cfg80211_chandef_identical(&ctx->conf.def, chandef)) {
 351                 ieee80211_recalc_chanctx_min_def(local, ctx);
 352                 return;
 353         }
 354
 355         WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
 356
 357         ctx->conf.def = *chandef;
 358         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
 359         ieee80211_recalc_chanctx_min_def(local, ctx);
 360
 361         if (!local->use_chanctx) {
 362                 local->_oper_chandef = *chandef;
 363                 ieee80211_hw_config(local, 0);
 364         }
 365 }
 366
 367 static struct ieee80211_chanctx *
 368 ieee80211_find_chanctx(struct ieee80211_local *local,
 369                        const struct cfg80211_chan_def *chandef,
 370                        enum ieee80211_chanctx_mode mode)
 371 {
 372         struct ieee80211_chanctx *ctx;
 373
 374         lockdep_assert_held(&local->chanctx_mtx);
 375
 376         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 377                 return NULL;
 378
 379         list_for_each_entry(ctx, &local->chanctx_list, list) {
 380                 const struct cfg80211_chan_def *compat;
 381
 382                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
 383                         continue;
 384
 385                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 386                         continue;
 387
 388                 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
 389                 if (!compat)
 390                         continue;
 391
 392                 compat = ieee80211_chanctx_reserved_chandef(local, ctx,
 393                                                             compat);
 394                 if (!compat)
 395                         continue;
 396
 397                 ieee80211_change_chanctx(local, ctx, compat);
 398
 399                 return ctx;
 400         }
 401
 402         return NULL;
 403 }
 404
 405 bool ieee80211_is_radar_required(struct ieee80211_local *local)
 406 {
 407         struct ieee80211_sub_if_data *sdata;
 408
 409         lockdep_assert_held(&local->mtx);
 410
 411         rcu_read_lock();
 412         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 413                 if (sdata->radar_required) {
 414                         rcu_read_unlock();
 415                         return true;
 416                 }
 417         }
 418         rcu_read_unlock();
 419
 420         return false;
 421 }
 422
 423 static bool
 424 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
 425                                  struct ieee80211_chanctx *ctx)
 426 {
 427         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 428         struct ieee80211_sub_if_data *sdata;
 429         bool required = false;
 430
 431         lockdep_assert_held(&local->chanctx_mtx);
 432         lockdep_assert_held(&local->mtx);
 433
 434         rcu_read_lock();
 435         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 436                 if (!ieee80211_sdata_running(sdata))
 437                         continue;
 438                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 439                         continue;
 440                 if (!sdata->radar_required)
 441                         continue;
 442
 443                 required = true;
 444                 break;
 445         }
 446         rcu_read_unlock();
 447
 448         return required;
 449 }
 450
 451 static struct ieee80211_chanctx *
 452 ieee80211_alloc_chanctx(struct ieee80211_local *local,
 453                         const struct cfg80211_chan_def *chandef,
 454                         enum ieee80211_chanctx_mode mode)
 455 {
 456         struct ieee80211_chanctx *ctx;
 457
 458         lockdep_assert_held(&local->chanctx_mtx);
 459
 460         ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
 461         if (!ctx)
 462                 return NULL;
 463
 464         INIT_LIST_HEAD(&ctx->assigned_vifs);
 465         INIT_LIST_HEAD(&ctx->reserved_vifs);
 466         ctx->conf.def = *chandef;
 467         ctx->conf.rx_chains_static = 1;
 468         ctx->conf.rx_chains_dynamic = 1;
 469         ctx->mode = mode;
 470         ctx->conf.radar_enabled = false;
 471         ieee80211_recalc_chanctx_min_def(local, ctx);
 472
 473         return ctx;
 474 }
 475
 476 static int ieee80211_add_chanctx(struct ieee80211_local *local,
 477                                  struct ieee80211_chanctx *ctx)
 478 {
 479         u32 changed;
 480         int err;
 481
 482         lockdep_assert_held(&local->mtx);
 483         lockdep_assert_held(&local->chanctx_mtx);
 484
 485         if (!local->use_chanctx)
 486                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 487
 488         /* turn idle off *before* setting channel -- some drivers need that */
 489         changed = ieee80211_idle_off(local);
 490         if (changed)
 491                 ieee80211_hw_config(local, changed);
 492
 493         if (!local->use_chanctx) {
 494                 local->_oper_chandef = ctx->conf.def;
 495                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 496         } else {
 497                 err = drv_add_chanctx(local, ctx);
 498                 if (err) {
 499                         ieee80211_recalc_idle(local);
 500                         return err;
 501                 }
 502         }
 503
 504         return 0;
 505 }
 506
 507 static struct ieee80211_chanctx *
 508 ieee80211_new_chanctx(struct ieee80211_local *local,
 509                       const struct cfg80211_chan_def *chandef,
 510                       enum ieee80211_chanctx_mode mode)
 511 {
 512         struct ieee80211_chanctx *ctx;
 513         int err;
 514
 515         lockdep_assert_held(&local->mtx);
 516         lockdep_assert_held(&local->chanctx_mtx);
 517
 518         ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 519         if (!ctx)
 520                 return ERR_PTR(-ENOMEM);
 521
 522         err = ieee80211_add_chanctx(local, ctx);
 523         if (err) {
 524                 kfree(ctx);
 525                 return ERR_PTR(err);
 526         }
 527
 528         list_add_rcu(&ctx->list, &local->chanctx_list);
 529         return ctx;
 530 }
 531
 532 static void ieee80211_del_chanctx(struct ieee80211_local *local,
 533                                   struct ieee80211_chanctx *ctx)
 534 {
 535         lockdep_assert_held(&local->chanctx_mtx);
 536
 537         if (!local->use_chanctx) {
 538                 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
 539                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 540                 chandef->center_freq1 = chandef->chan->center_freq;
 541                 chandef->freq1_offset = chandef->chan->freq_offset;
 542                 chandef->center_freq2 = 0;
 543
 544                 /* NOTE: Disabling radar is only valid here for
 545                  * single channel context. To be sure, check it ...
 546                  */
 547                 WARN_ON(local->hw.conf.radar_enabled &&
 548                         !list_empty(&local->chanctx_list));
 549
 550                 local->hw.conf.radar_enabled = false;
 551
 552                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 553         } else {
 554                 drv_remove_chanctx(local, ctx);
 555         }
 556
 557         ieee80211_recalc_idle(local);
 558 }
 559
 560 static void ieee80211_free_chanctx(struct ieee80211_local *local,
 561                                    struct ieee80211_chanctx *ctx)
 562 {
 563         lockdep_assert_held(&local->chanctx_mtx);
 564
 565         WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
 566
 567         list_del_rcu(&ctx->list);
 568         ieee80211_del_chanctx(local, ctx);
 569         kfree_rcu(ctx, rcu_head);
 570 }
 571
 572 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 573                                        struct ieee80211_chanctx *ctx)
 574 {
 575         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 576         struct ieee80211_sub_if_data *sdata;
 577         const struct cfg80211_chan_def *compat = NULL;
 578         struct sta_info *sta;
 579
 580         lockdep_assert_held(&local->chanctx_mtx);
 581
 582         rcu_read_lock();
 583         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 584
 585                 if (!ieee80211_sdata_running(sdata))
 586                         continue;
 587                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 588                         continue;
 589                 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 590                         continue;
 591
 592                 if (!compat)
 593                         compat = &sdata->vif.bss_conf.chandef;
 594
 595                 compat = cfg80211_chandef_compatible(
 596                                 &sdata->vif.bss_conf.chandef, compat);
 597                 if (WARN_ON_ONCE(!compat))
 598                         break;
 599         }
 600
 601         /* TDLS peers can sometimes affect the chandef width */
 602         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 603                 if (!sta->uploaded ||
 604                     !test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW) ||
 605                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
 606                     !sta->tdls_chandef.chan)
 607                         continue;
 608
 609                 compat = cfg80211_chandef_compatible(&sta->tdls_chandef,
 610                                                      compat);
 611                 if (WARN_ON_ONCE(!compat))
 612                         break;
 613         }
 614         rcu_read_unlock();
 615
 616         if (!compat)
 617                 return;
 618
 619         ieee80211_change_chanctx(local, ctx, compat);
 620 }
 621
 622 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
 623                                            struct ieee80211_chanctx *chanctx)
 624 {
 625         bool radar_enabled;
 626
 627         lockdep_assert_held(&local->chanctx_mtx);
 628         /* for ieee80211_is_radar_required */
 629         lockdep_assert_held(&local->mtx);
 630
 631         radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
 632
 633         if (radar_enabled == chanctx->conf.radar_enabled)
 634                 return;
 635
 636         chanctx->conf.radar_enabled = radar_enabled;
 637
 638         if (!local->use_chanctx) {
 639                 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
 640                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 641         }
 642
 643         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
 644 }
 645
 646 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 647                                         struct ieee80211_chanctx *new_ctx)
 648 {
 649         struct ieee80211_local *local = sdata->local;
 650         struct ieee80211_chanctx_conf *conf;
 651         struct ieee80211_chanctx *curr_ctx = NULL;
 652         int ret = 0;
 653
 654         if (WARN_ON(sdata->vif.type == NL80211_IFTYPE_NAN))
 655                 return -ENOTSUPP;
 656
 657         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 658                                          lockdep_is_held(&local->chanctx_mtx));
 659
 660         if (conf) {
 661                 curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
 662
 663                 drv_unassign_vif_chanctx(local, sdata, curr_ctx);
 664                 conf = NULL;
 665                 list_del(&sdata->assigned_chanctx_list);
 666         }
 667
 668         if (new_ctx) {
 669                 ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
 670                 if (ret)
 671                         goto out;
 672
 673                 conf = &new_ctx->conf;
 674                 list_add(&sdata->assigned_chanctx_list,
 675                          &new_ctx->assigned_vifs);
 676         }
 677
 678 out:
 679         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
 680
 681         sdata->vif.bss_conf.idle = !conf;
 682
 683         if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
 684                 ieee80211_recalc_chanctx_chantype(local, curr_ctx);
 685                 ieee80211_recalc_smps_chanctx(local, curr_ctx);
 686                 ieee80211_recalc_radar_chanctx(local, curr_ctx);
 687                 ieee80211_recalc_chanctx_min_def(local, curr_ctx);
 688         }
 689
 690         if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
 691                 ieee80211_recalc_txpower(sdata, false);
 692                 ieee80211_recalc_chanctx_min_def(local, new_ctx);
 693         }
 694
 695         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
 696             sdata->vif.type != NL80211_IFTYPE_MONITOR)
 697                 ieee80211_bss_info_change_notify(sdata,
 698                                                  BSS_CHANGED_IDLE);
 699
 700         ieee80211_check_fast_xmit_iface(sdata);
 701
 702         return ret;
 703 }
 704
 705 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 706                                    struct ieee80211_chanctx *chanctx)
 707 {
 708         struct ieee80211_sub_if_data *sdata;
 709         u8 rx_chains_static, rx_chains_dynamic;
 710
 711         lockdep_assert_held(&local->chanctx_mtx);
 712
 713         rx_chains_static = 1;
 714         rx_chains_dynamic = 1;
 715
 716         rcu_read_lock();
 717         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 718                 u8 needed_static, needed_dynamic;
 719
 720                 if (!ieee80211_sdata_running(sdata))
 721                         continue;
 722
 723                 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
 724                                                 &chanctx->conf)
 725                         continue;
 726
 727                 switch (sdata->vif.type) {
 728                 case NL80211_IFTYPE_P2P_DEVICE:
 729                 case NL80211_IFTYPE_NAN:
 730                         continue;
 731                 case NL80211_IFTYPE_STATION:
 732                         if (!sdata->u.mgd.associated)
 733                                 continue;
 734                         break;
 735                 case NL80211_IFTYPE_AP_VLAN:
 736                         continue;
 737                 case NL80211_IFTYPE_AP:
 738                 case NL80211_IFTYPE_ADHOC:
 739                 case NL80211_IFTYPE_WDS:
 740                 case NL80211_IFTYPE_MESH_POINT:
 741                 case NL80211_IFTYPE_OCB:
 742                         break;
 743                 default:
 744                         WARN_ON_ONCE(1);
 745                 }
 746
 747                 switch (sdata->smps_mode) {
 748                 default:
 749                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
 750                                   sdata->smps_mode);
 751                         fallthrough;
 752                 case IEEE80211_SMPS_OFF:
 753                         needed_static = sdata->needed_rx_chains;
 754                         needed_dynamic = sdata->needed_rx_chains;
 755                         break;
 756                 case IEEE80211_SMPS_DYNAMIC:
 757                         needed_static = 1;
 758                         needed_dynamic = sdata->needed_rx_chains;
 759                         break;
 760                 case IEEE80211_SMPS_STATIC:
 761                         needed_static = 1;
 762                         needed_dynamic = 1;
 763                         break;
 764                 }
 765
 766                 rx_chains_static = max(rx_chains_static, needed_static);
 767                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
 768         }
 769
 770         /* Disable SMPS for the monitor interface */
 771         sdata = rcu_dereference(local->monitor_sdata);
 772         if (sdata &&
 773             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
 774                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
 775
 776         rcu_read_unlock();
 777
 778         if (!local->use_chanctx) {
 779                 if (rx_chains_static > 1)
 780                         local->smps_mode = IEEE80211_SMPS_OFF;
 781                 else if (rx_chains_dynamic > 1)
 782                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
 783                 else
 784                         local->smps_mode = IEEE80211_SMPS_STATIC;
 785                 ieee80211_hw_config(local, 0);
 786         }
 787
 788         if (rx_chains_static == chanctx->conf.rx_chains_static &&
 789             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
 790                 return;
 791
 792         chanctx->conf.rx_chains_static = rx_chains_static;
 793         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
 794         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
 795 }
 796
 797 static void
 798 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 799                                       bool clear)
 800 {
 801         struct ieee80211_local *local __maybe_unused = sdata->local;
 802         struct ieee80211_sub_if_data *vlan;
 803         struct ieee80211_chanctx_conf *conf;
 804
 805         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
 806                 return;
 807
 808         lockdep_assert_held(&local->mtx);
 809
 810         /* Check that conf exists, even when clearing this function
 811          * must be called with the AP's channel context still there
 812          * as it would otherwise cause VLANs to have an invalid
 813          * channel context pointer for a while, possibly pointing
 814          * to a channel context that has already been freed.
 815          */
 816         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 817                                          lockdep_is_held(&local->chanctx_mtx));
 818         WARN_ON(!conf);
 819
 820         if (clear)
 821                 conf = NULL;
 822
 823         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 824                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
 825 }
 826
 827 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 828                                          bool clear)
 829 {
 830         struct ieee80211_local *local = sdata->local;
 831
 832         mutex_lock(&local->chanctx_mtx);
 833
 834         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
 835
 836         mutex_unlock(&local->chanctx_mtx);
 837 }
 838
 839 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
 840 {
 841         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
 842
 843         lockdep_assert_held(&sdata->local->chanctx_mtx);
 844
 845         if (WARN_ON(!ctx))
 846                 return -EINVAL;
 847
 848         list_del(&sdata->reserved_chanctx_list);
 849         sdata->reserved_chanctx = NULL;
 850
 851         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
 852                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
 853                         if (WARN_ON(!ctx->replace_ctx))
 854                                 return -EINVAL;
 855
 856                         WARN_ON(ctx->replace_ctx->replace_state !=
 857                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
 858                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
 859
 860                         ctx->replace_ctx->replace_ctx = NULL;
 861                         ctx->replace_ctx->replace_state =
 862                                         IEEE80211_CHANCTX_REPLACE_NONE;
 863
 864                         list_del_rcu(&ctx->list);
 865                         kfree_rcu(ctx, rcu_head);
 866                 } else {
 867                         ieee80211_free_chanctx(sdata->local, ctx);
 868                 }
 869         }
 870
 871         return 0;
 872 }
 873
 874 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
 875                                   const struct cfg80211_chan_def *chandef,
 876                                   enum ieee80211_chanctx_mode mode,
 877                                   bool radar_required)
 878 {
 879         struct ieee80211_local *local = sdata->local;
 880         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
 881
 882         lockdep_assert_held(&local->chanctx_mtx);
 883
 884         curr_ctx = ieee80211_vif_get_chanctx(sdata);
 885         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
 886                 return -ENOTSUPP;
 887
 888         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
 889         if (!new_ctx) {
 890                 if (ieee80211_can_create_new_chanctx(local)) {
 891                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
 892                         if (IS_ERR(new_ctx))
 893                                 return PTR_ERR(new_ctx);
 894                 } else {
 895                         if (!curr_ctx ||
 896                             (curr_ctx->replace_state ==
 897                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 898                             !list_empty(&curr_ctx->reserved_vifs)) {
 899                                 /*
 900                                  * Another vif already requested this context
 901                                  * for a reservation. Find another one hoping
 902                                  * all vifs assigned to it will also switch
 903                                  * soon enough.
 904                                  *
 905                                  * TODO: This needs a little more work as some
 906                                  * cases (more than 2 chanctx capable devices)
 907                                  * may fail which could otherwise succeed
 908                                  * provided some channel context juggling was
 909                                  * performed.
 910                                  *
 911                                  * Consider ctx1..3, vif1..6, each ctx has 2
 912                                  * vifs. vif1 and vif2 from ctx1 request new
 913                                  * different chandefs starting 2 in-place
 914                                  * reserations with ctx4 and ctx5 replacing
 915                                  * ctx1 and ctx2 respectively. Next vif5 and
 916                                  * vif6 from ctx3 reserve ctx4. If vif3 and
 917                                  * vif4 remain on ctx2 as they are then this
 918                                  * fails unless `replace_ctx` from ctx5 is
 919                                  * replaced with ctx3.
 920                                  */
 921                                 list_for_each_entry(ctx, &local->chanctx_list,
 922                                                     list) {
 923                                         if (ctx->replace_state !=
 924                                             IEEE80211_CHANCTX_REPLACE_NONE)
 925                                                 continue;
 926
 927                                         if (!list_empty(&ctx->reserved_vifs))
 928                                                 continue;
 929
 930                                         curr_ctx = ctx;
 931                                         break;
 932                                 }
 933                         }
 934
 935                         /*
 936                          * If that's true then all available contexts already
 937                          * have reservations and cannot be used.
 938                          */
 939                         if (!curr_ctx ||
 940                             (curr_ctx->replace_state ==
 941                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 942                             !list_empty(&curr_ctx->reserved_vifs))
 943                                 return -EBUSY;
 944
 945                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 946                         if (!new_ctx)
 947                                 return -ENOMEM;
 948
 949                         new_ctx->replace_ctx = curr_ctx;
 950                         new_ctx->replace_state =
 951                                         IEEE80211_CHANCTX_REPLACES_OTHER;
 952
 953                         curr_ctx->replace_ctx = new_ctx;
 954                         curr_ctx->replace_state =
 955                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
 956
 957                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
 958                 }
 959         }
 960
 961         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
 962         sdata->reserved_chanctx = new_ctx;
 963         sdata->reserved_chandef = *chandef;
 964         sdata->reserved_radar_required = radar_required;
 965         sdata->reserved_ready = false;
 966
 967         return 0;
 968 }
 969
 970 static void
 971 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
 972 {
 973         switch (sdata->vif.type) {
 974         case NL80211_IFTYPE_ADHOC:
 975         case NL80211_IFTYPE_AP:
 976         case NL80211_IFTYPE_MESH_POINT:
 977         case NL80211_IFTYPE_OCB:
 978                 ieee80211_queue_work(&sdata->local->hw,
 979                                      &sdata->csa_finalize_work);
 980                 break;
 981         case NL80211_IFTYPE_STATION:
 982                 ieee80211_queue_work(&sdata->local->hw,
 983                                      &sdata->u.mgd.chswitch_work);
 984                 break;
 985         case NL80211_IFTYPE_UNSPECIFIED:
 986         case NL80211_IFTYPE_AP_VLAN:
 987         case NL80211_IFTYPE_WDS:
 988         case NL80211_IFTYPE_MONITOR:
 989         case NL80211_IFTYPE_P2P_CLIENT:
 990         case NL80211_IFTYPE_P2P_GO:
 991         case NL80211_IFTYPE_P2P_DEVICE:
 992         case NL80211_IFTYPE_NAN:
 993         case NUM_NL80211_IFTYPES:
 994                 WARN_ON(1);
 995                 break;
 996         }
 997 }
 998
 999 static void
1000 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
1001                              const struct cfg80211_chan_def *chandef)
1002 {
1003         struct ieee80211_sub_if_data *vlan;
1004
1005         sdata->vif.bss_conf.chandef = *chandef;
1006
1007         if (sdata->vif.type != NL80211_IFTYPE_AP)
1008                 return;
1009
1010         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
1011                 vlan->vif.bss_conf.chandef = *chandef;
1012 }
1013
1014 static int
1015 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
1016 {
1017         struct ieee80211_local *local = sdata->local;
1018         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
1019         struct ieee80211_chanctx *old_ctx, *new_ctx;
1020         const struct cfg80211_chan_def *chandef;
1021         u32 changed = 0;
1022         int err;
1023
1024         lockdep_assert_held(&local->mtx);
1025         lockdep_assert_held(&local->chanctx_mtx);
1026
1027         new_ctx = sdata->reserved_chanctx;
1028         old_ctx = ieee80211_vif_get_chanctx(sdata);
1029
1030         if (WARN_ON(!sdata->reserved_ready))
1031                 return -EBUSY;
1032
1033         if (WARN_ON(!new_ctx))
1034                 return -EINVAL;
1035
1036         if (WARN_ON(!old_ctx))
1037                 return -EINVAL;
1038
1039         if (WARN_ON(new_ctx->replace_state ==
1040                     IEEE80211_CHANCTX_REPLACES_OTHER))
1041                 return -EINVAL;
1042
1043         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1044                                 &sdata->reserved_chandef);
1045         if (WARN_ON(!chandef))
1046                 return -EINVAL;
1047
1048         ieee80211_change_chanctx(local, new_ctx, chandef);
1049
1050         vif_chsw[0].vif = &sdata->vif;
1051         vif_chsw[0].old_ctx = &old_ctx->conf;
1052         vif_chsw[0].new_ctx = &new_ctx->conf;
1053
1054         list_del(&sdata->reserved_chanctx_list);
1055         sdata->reserved_chanctx = NULL;
1056
1057         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1058                                      CHANCTX_SWMODE_REASSIGN_VIF);
1059         if (err) {
1060                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1061                         ieee80211_free_chanctx(local, new_ctx);
1062
1063                 goto out;
1064         }
1065
1066         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1067         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1068
1069         if (sdata->vif.type == NL80211_IFTYPE_AP)
1070                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1071
1072         ieee80211_check_fast_xmit_iface(sdata);
1073
1074         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1075                 ieee80211_free_chanctx(local, old_ctx);
1076
1077         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1078                 changed = BSS_CHANGED_BANDWIDTH;
1079
1080         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1081
1082         ieee80211_recalc_smps_chanctx(local, new_ctx);
1083         ieee80211_recalc_radar_chanctx(local, new_ctx);
1084         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1085
1086         if (changed)
1087                 ieee80211_bss_info_change_notify(sdata, changed);
1088
1089 out:
1090         ieee80211_vif_chanctx_reservation_complete(sdata);
1091         return err;
1092 }
1093
1094 static int
1095 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1096 {
1097         struct ieee80211_local *local = sdata->local;
1098         struct ieee80211_chanctx *old_ctx, *new_ctx;
1099         const struct cfg80211_chan_def *chandef;
1100         int err;
1101
1102         old_ctx = ieee80211_vif_get_chanctx(sdata);
1103         new_ctx = sdata->reserved_chanctx;
1104
1105         if (WARN_ON(!sdata->reserved_ready))
1106                 return -EINVAL;
1107
1108         if (WARN_ON(old_ctx))
1109                 return -EINVAL;
1110
1111         if (WARN_ON(!new_ctx))
1112                 return -EINVAL;
1113
1114         if (WARN_ON(new_ctx->replace_state ==
1115                     IEEE80211_CHANCTX_REPLACES_OTHER))
1116                 return -EINVAL;
1117
1118         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1119                                 &sdata->reserved_chandef);
1120         if (WARN_ON(!chandef))
1121                 return -EINVAL;
1122
1123         ieee80211_change_chanctx(local, new_ctx, chandef);
1124
1125         list_del(&sdata->reserved_chanctx_list);
1126         sdata->reserved_chanctx = NULL;
1127
1128         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1129         if (err) {
1130                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1131                         ieee80211_free_chanctx(local, new_ctx);
1132
1133                 goto out;
1134         }
1135
1136 out:
1137         ieee80211_vif_chanctx_reservation_complete(sdata);
1138         return err;
1139 }
1140
1141 static bool
1142 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1143 {
1144         struct ieee80211_chanctx *old_ctx, *new_ctx;
1145
1146         lockdep_assert_held(&sdata->local->chanctx_mtx);
1147
1148         new_ctx = sdata->reserved_chanctx;
1149         old_ctx = ieee80211_vif_get_chanctx(sdata);
1150
1151         if (!old_ctx)
1152                 return false;
1153
1154         if (WARN_ON(!new_ctx))
1155                 return false;
1156
1157         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1158                 return false;
1159
1160         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1161                 return false;
1162
1163         return true;
1164 }
1165
1166 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1167                                         struct ieee80211_chanctx *new_ctx)
1168 {
1169         const struct cfg80211_chan_def *chandef;
1170
1171         lockdep_assert_held(&local->mtx);
1172         lockdep_assert_held(&local->chanctx_mtx);
1173
1174         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1175         if (WARN_ON(!chandef))
1176                 return -EINVAL;
1177
1178         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1179         local->_oper_chandef = *chandef;
1180         ieee80211_hw_config(local, 0);
1181
1182         return 0;
1183 }
1184
1185 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1186                                       int n_vifs)
1187 {
1188         struct ieee80211_vif_chanctx_switch *vif_chsw;
1189         struct ieee80211_sub_if_data *sdata;
1190         struct ieee80211_chanctx *ctx, *old_ctx;
1191         int i, err;
1192
1193         lockdep_assert_held(&local->mtx);
1194         lockdep_assert_held(&local->chanctx_mtx);
1195
1196         vif_chsw = kcalloc(n_vifs, sizeof(vif_chsw[0]), GFP_KERNEL);
1197         if (!vif_chsw)
1198                 return -ENOMEM;
1199
1200         i = 0;
1201         list_for_each_entry(ctx, &local->chanctx_list, list) {
1202                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1203                         continue;
1204
1205                 if (WARN_ON(!ctx->replace_ctx)) {
1206                         err = -EINVAL;
1207                         goto out;
1208                 }
1209
1210                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1211                                     reserved_chanctx_list) {
1212                         if (!ieee80211_vif_has_in_place_reservation(
1213                                         sdata))
1214                                 continue;
1215
1216                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1217                         vif_chsw[i].vif = &sdata->vif;
1218                         vif_chsw[i].old_ctx = &old_ctx->conf;
1219                         vif_chsw[i].new_ctx = &ctx->conf;
1220
1221                         i++;
1222                 }
1223         }
1224
1225         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1226                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1227
1228 out:
1229         kfree(vif_chsw);
1230         return err;
1231 }
1232
1233 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1234 {
1235         struct ieee80211_chanctx *ctx;
1236         int err;
1237
1238         lockdep_assert_held(&local->mtx);
1239         lockdep_assert_held(&local->chanctx_mtx);
1240
1241         list_for_each_entry(ctx, &local->chanctx_list, list) {
1242                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1243                         continue;
1244
1245                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1246                         continue;
1247
1248                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1249                 err = ieee80211_add_chanctx(local, ctx);
1250                 if (err)
1251                         goto err;
1252         }
1253
1254         return 0;
1255
1256 err:
1257         WARN_ON(ieee80211_add_chanctx(local, ctx));
1258         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1259                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1260                         continue;
1261
1262                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1263                         continue;
1264
1265                 ieee80211_del_chanctx(local, ctx);
1266                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1267         }
1268
1269         return err;
1270 }
1271
1272 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1273 {
1274         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1275         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1276         struct ieee80211_chanctx *new_ctx = NULL;
1277         int err, n_assigned, n_reserved, n_ready;
1278         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1279
1280         lockdep_assert_held(&local->mtx);
1281         lockdep_assert_held(&local->chanctx_mtx);
1282
1283         /*
1284          * If there are 2 independent pairs of channel contexts performing
1285          * cross-switch of their vifs this code will still wait until both are
1286          * ready even though it could be possible to switch one before the
1287          * other is ready.
1288          *
1289          * For practical reasons and code simplicity just do a single huge
1290          * switch.
1291          */
1292
1293         /*
1294          * Verify if the reservation is still feasible.
1295          *  - if it's not then disconnect
1296          *  - if it is but not all vifs necessary are ready then defer
1297          */
1298
1299         list_for_each_entry(ctx, &local->chanctx_list, list) {
1300                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1301                         continue;
1302
1303                 if (WARN_ON(!ctx->replace_ctx)) {
1304                         err = -EINVAL;
1305                         goto err;
1306                 }
1307
1308                 if (!local->use_chanctx)
1309                         new_ctx = ctx;
1310
1311                 n_ctx++;
1312
1313                 n_assigned = 0;
1314                 n_reserved = 0;
1315                 n_ready = 0;
1316
1317                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1318                                     assigned_chanctx_list) {
1319                         n_assigned++;
1320                         if (sdata->reserved_chanctx) {
1321                                 n_reserved++;
1322                                 if (sdata->reserved_ready)
1323                                         n_ready++;
1324                         }
1325                 }
1326
1327                 if (n_assigned != n_reserved) {
1328                         if (n_ready == n_reserved) {
1329                                 wiphy_info(local->hw.wiphy,
1330                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1331                                 err = -EBUSY;
1332                                 goto err;
1333                         }
1334
1335                         return -EAGAIN;
1336                 }
1337
1338                 ctx->conf.radar_enabled = false;
1339                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1340                                     reserved_chanctx_list) {
1341                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1342                             !sdata->reserved_ready)
1343                                 return -EAGAIN;
1344
1345                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1346                         if (old_ctx) {
1347                                 if (old_ctx->replace_state ==
1348                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1349                                         n_vifs_switch++;
1350                                 else
1351                                         n_vifs_assign++;
1352                         } else {
1353                                 n_vifs_ctxless++;
1354                         }
1355
1356                         if (sdata->reserved_radar_required)
1357                                 ctx->conf.radar_enabled = true;
1358                 }
1359         }
1360
1361         if (WARN_ON(n_ctx == 0) ||
1362             WARN_ON(n_vifs_switch == 0 &&
1363                     n_vifs_assign == 0 &&
1364                     n_vifs_ctxless == 0) ||
1365             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1366             WARN_ON(!new_ctx && !local->use_chanctx)) {
1367                 err = -EINVAL;
1368                 goto err;
1369         }
1370
1371         /*
1372          * All necessary vifs are ready. Perform the switch now depending on
1373          * reservations and driver capabilities.
1374          */
1375
1376         if (local->use_chanctx) {
1377                 if (n_vifs_switch > 0) {
1378                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1379                         if (err)
1380                                 goto err;
1381                 }
1382
1383                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1384                         err = ieee80211_chsw_switch_ctxs(local);
1385                         if (err)
1386                                 goto err;
1387                 }
1388         } else {
1389                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1390                 if (err)
1391                         goto err;
1392         }
1393
1394         /*
1395          * Update all structures, values and pointers to point to new channel
1396          * context(s).
1397          */
1398         list_for_each_entry(ctx, &local->chanctx_list, list) {
1399                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1400                         continue;
1401
1402                 if (WARN_ON(!ctx->replace_ctx)) {
1403                         err = -EINVAL;
1404                         goto err;
1405                 }
1406
1407                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1408                                     reserved_chanctx_list) {
1409                         u32 changed = 0;
1410
1411                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1412                                 continue;
1413
1414                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1415
1416                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1417                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1418                                                                       false);
1419
1420                         ieee80211_check_fast_xmit_iface(sdata);
1421
1422                         sdata->radar_required = sdata->reserved_radar_required;
1423
1424                         if (sdata->vif.bss_conf.chandef.width !=
1425                             sdata->reserved_chandef.width)
1426                                 changed = BSS_CHANGED_BANDWIDTH;
1427
1428                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1429                         if (changed)
1430                                 ieee80211_bss_info_change_notify(sdata,
1431                                                                  changed);
1432
1433                         ieee80211_recalc_txpower(sdata, false);
1434                 }
1435
1436                 ieee80211_recalc_chanctx_chantype(local, ctx);
1437                 ieee80211_recalc_smps_chanctx(local, ctx);
1438                 ieee80211_recalc_radar_chanctx(local, ctx);
1439                 ieee80211_recalc_chanctx_min_def(local, ctx);
1440
1441                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1442                                          reserved_chanctx_list) {
1443                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1444                                 continue;
1445
1446                         list_del(&sdata->reserved_chanctx_list);
1447                         list_move(&sdata->assigned_chanctx_list,
1448                                   &ctx->assigned_vifs);
1449                         sdata->reserved_chanctx = NULL;
1450
1451                         ieee80211_vif_chanctx_reservation_complete(sdata);
1452                 }
1453
1454                 /*
1455                  * This context might have been a dependency for an already
1456                  * ready re-assign reservation interface that was deferred. Do
1457                  * not propagate error to the caller though. The in-place
1458                  * reservation for originally requested interface has already
1459                  * succeeded at this point.
1460                  */
1461                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1462                                          reserved_chanctx_list) {
1463                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1464                                         sdata)))
1465                                 continue;
1466
1467                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1468                                 continue;
1469
1470                         if (!sdata->reserved_ready)
1471                                 continue;
1472
1473                         if (ieee80211_vif_get_chanctx(sdata))
1474                                 err = ieee80211_vif_use_reserved_reassign(
1475                                                 sdata);
1476                         else
1477                                 err = ieee80211_vif_use_reserved_assign(sdata);
1478
1479                         if (err) {
1480                                 sdata_info(sdata,
1481                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1482                                            err);
1483                                 ieee80211_vif_unreserve_chanctx(sdata);
1484                                 cfg80211_stop_iface(local->hw.wiphy,
1485                                                     &sdata->wdev,
1486                                                     GFP_KERNEL);
1487                         }
1488                 }
1489         }
1490
1491         /*
1492          * Finally free old contexts
1493          */
1494
1495         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1496                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1497                         continue;
1498
1499                 ctx->replace_ctx->replace_ctx = NULL;
1500                 ctx->replace_ctx->replace_state =
1501                                 IEEE80211_CHANCTX_REPLACE_NONE;
1502
1503                 list_del_rcu(&ctx->list);
1504                 kfree_rcu(ctx, rcu_head);
1505         }
1506
1507         return 0;
1508
1509 err:
1510         list_for_each_entry(ctx, &local->chanctx_list, list) {
1511                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1512                         continue;
1513
1514                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1515                                          reserved_chanctx_list) {
1516                         ieee80211_vif_unreserve_chanctx(sdata);
1517                         ieee80211_vif_chanctx_reservation_complete(sdata);
1518                 }
1519         }
1520
1521         return err;
1522 }
1523
1524 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1525 {
1526         struct ieee80211_local *local = sdata->local;
1527         struct ieee80211_chanctx_conf *conf;
1528         struct ieee80211_chanctx *ctx;
1529         bool use_reserved_switch = false;
1530
1531         lockdep_assert_held(&local->chanctx_mtx);
1532
1533         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1534                                          lockdep_is_held(&local->chanctx_mtx));
1535         if (!conf)
1536                 return;
1537
1538         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1539
1540         if (sdata->reserved_chanctx) {
1541                 if (sdata->reserved_chanctx->replace_state ==
1542                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1543                     ieee80211_chanctx_num_reserved(local,
1544                                                    sdata->reserved_chanctx) > 1)
1545                         use_reserved_switch = true;
1546
1547                 ieee80211_vif_unreserve_chanctx(sdata);
1548         }
1549
1550         ieee80211_assign_vif_chanctx(sdata, NULL);
1551         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1552                 ieee80211_free_chanctx(local, ctx);
1553
1554         sdata->radar_required = false;
1555
1556         /* Unreserving may ready an in-place reservation. */
1557         if (use_reserved_switch)
1558                 ieee80211_vif_use_reserved_switch(local);
1559 }
1560
1561 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1562                               const struct cfg80211_chan_def *chandef,
1563                               enum ieee80211_chanctx_mode mode)
1564 {
1565         struct ieee80211_local *local = sdata->local;
1566         struct ieee80211_chanctx *ctx;
1567         u8 radar_detect_width = 0;
1568         int ret;
1569
1570         lockdep_assert_held(&local->mtx);
1571
1572         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1573
1574         mutex_lock(&local->chanctx_mtx);
1575
1576         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1577                                             chandef,
1578                                             sdata->wdev.iftype);
1579         if (ret < 0)
1580                 goto out;
1581         if (ret > 0)
1582                 radar_detect_width = BIT(chandef->width);
1583
1584         sdata->radar_required = ret;
1585
1586         ret = ieee80211_check_combinations(sdata, chandef, mode,
1587                                            radar_detect_width);
1588         if (ret < 0)
1589                 goto out;
1590
1591         __ieee80211_vif_release_channel(sdata);
1592
1593         ctx = ieee80211_find_chanctx(local, chandef, mode);
1594         if (!ctx)
1595                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1596         if (IS_ERR(ctx)) {
1597                 ret = PTR_ERR(ctx);
1598                 goto out;
1599         }
1600
1601         ieee80211_vif_update_chandef(sdata, chandef);
1602
1603         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1604         if (ret) {
1605                 /* if assign fails refcount stays the same */
1606                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1607                         ieee80211_free_chanctx(local, ctx);
1608                 goto out;
1609         }
1610
1611         ieee80211_recalc_smps_chanctx(local, ctx);
1612         ieee80211_recalc_radar_chanctx(local, ctx);
1613  out:
1614         if (ret)
1615                 sdata->radar_required = false;
1616
1617         mutex_unlock(&local->chanctx_mtx);
1618         return ret;
1619 }
1620
1621 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1622 {
1623         struct ieee80211_local *local = sdata->local;
1624         struct ieee80211_chanctx *new_ctx;
1625         struct ieee80211_chanctx *old_ctx;
1626         int err;
1627
1628         lockdep_assert_held(&local->mtx);
1629         lockdep_assert_held(&local->chanctx_mtx);
1630
1631         new_ctx = sdata->reserved_chanctx;
1632         old_ctx = ieee80211_vif_get_chanctx(sdata);
1633
1634         if (WARN_ON(!new_ctx))
1635                 return -EINVAL;
1636
1637         if (WARN_ON(new_ctx->replace_state ==
1638                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1639                 return -EINVAL;
1640
1641         if (WARN_ON(sdata->reserved_ready))
1642                 return -EINVAL;
1643
1644         sdata->reserved_ready = true;
1645
1646         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1647                 if (old_ctx)
1648                         err = ieee80211_vif_use_reserved_reassign(sdata);
1649                 else
1650                         err = ieee80211_vif_use_reserved_assign(sdata);
1651
1652                 if (err)
1653                         return err;
1654         }
1655
1656         /*
1657          * In-place reservation may need to be finalized now either if:
1658          *  a) sdata is taking part in the swapping itself and is the last one
1659          *  b) sdata has switched with a re-assign reservation to an existing
1660          *     context readying in-place switching of old_ctx
1661          *
1662          * In case of (b) do not propagate the error up because the requested
1663          * sdata already switched successfully. Just spill an extra warning.
1664          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1665          * interfaces upon failure.
1666          */
1667         if ((old_ctx &&
1668              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1669             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1670                 err = ieee80211_vif_use_reserved_switch(local);
1671                 if (err && err != -EAGAIN) {
1672                         if (new_ctx->replace_state ==
1673                             IEEE80211_CHANCTX_REPLACES_OTHER)
1674                                 return err;
1675
1676                         wiphy_info(local->hw.wiphy,
1677                                    "depending in-place reservation failed (err=%d)\n",
1678                                    err);
1679                 }
1680         }
1681
1682         return 0;
1683 }
1684
1685 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1686                                    const struct cfg80211_chan_def *chandef,
1687                                    u32 *changed)
1688 {
1689         struct ieee80211_local *local = sdata->local;
1690         struct ieee80211_chanctx_conf *conf;
1691         struct ieee80211_chanctx *ctx;
1692         const struct cfg80211_chan_def *compat;
1693         int ret;
1694
1695         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1696                                      IEEE80211_CHAN_DISABLED))
1697                 return -EINVAL;
1698
1699         mutex_lock(&local->chanctx_mtx);
1700         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1701                 ret = 0;
1702                 goto out;
1703         }
1704
1705         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1706             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1707                 ret = -EINVAL;
1708                 goto out;
1709         }
1710
1711         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1712                                          lockdep_is_held(&local->chanctx_mtx));
1713         if (!conf) {
1714                 ret = -EINVAL;
1715                 goto out;
1716         }
1717
1718         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1719
1720         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1721         if (!compat) {
1722                 ret = -EINVAL;
1723                 goto out;
1724         }
1725
1726         switch (ctx->replace_state) {
1727         case IEEE80211_CHANCTX_REPLACE_NONE:
1728                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1729                         ret = -EBUSY;
1730                         goto out;
1731                 }
1732                 break;
1733         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1734                 /* TODO: Perhaps the bandwidth change could be treated as a
1735                  * reservation itself? */
1736                 ret = -EBUSY;
1737                 goto out;
1738         case IEEE80211_CHANCTX_REPLACES_OTHER:
1739                 /* channel context that is going to replace another channel
1740                  * context doesn't really exist and shouldn't be assigned
1741                  * anywhere yet */
1742                 WARN_ON(1);
1743                 break;
1744         }
1745
1746         ieee80211_vif_update_chandef(sdata, chandef);
1747
1748         ieee80211_recalc_chanctx_chantype(local, ctx);
1749
1750         *changed |= BSS_CHANGED_BANDWIDTH;
1751         ret = 0;
1752  out:
1753         mutex_unlock(&local->chanctx_mtx);
1754         return ret;
1755 }
1756
1757 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1758 {
1759         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1760
1761         lockdep_assert_held(&sdata->local->mtx);
1762
1763         mutex_lock(&sdata->local->chanctx_mtx);
1764         __ieee80211_vif_release_channel(sdata);
1765         mutex_unlock(&sdata->local->chanctx_mtx);
1766 }
1767
1768 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1769 {
1770         struct ieee80211_local *local = sdata->local;
1771         struct ieee80211_sub_if_data *ap;
1772         struct ieee80211_chanctx_conf *conf;
1773
1774         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1775                 return;
1776
1777         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1778
1779         mutex_lock(&local->chanctx_mtx);
1780
1781         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1782                                          lockdep_is_held(&local->chanctx_mtx));
1783         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1784         mutex_unlock(&local->chanctx_mtx);
1785 }
1786
1787 void ieee80211_iter_chan_contexts_atomic(
1788         struct ieee80211_hw *hw,
1789         void (*iter)(struct ieee80211_hw *hw,
1790                      struct ieee80211_chanctx_conf *chanctx_conf,
1791                      void *data),
1792         void *iter_data)
1793 {
1794         struct ieee80211_local *local = hw_to_local(hw);
1795         struct ieee80211_chanctx *ctx;
1796
1797         rcu_read_lock();
1798         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1799                 if (ctx->driver_present)
1800                         iter(hw, &ctx->conf, iter_data);
1801         rcu_read_unlock();
1802 }
1803 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);