net/mac80211/chan.c

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