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