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 int
 936 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
 937 {
 938         struct ieee80211_local *local = sdata->local;
 939         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
 940         struct ieee80211_chanctx *old_ctx, *new_ctx;
 941         const struct cfg80211_chan_def *chandef;
 942         u32 changed = 0;
 943         int err;
 944
 945         lockdep_assert_held(&local->mtx);
 946         lockdep_assert_held(&local->chanctx_mtx);
 947
 948         new_ctx = sdata->reserved_chanctx;
 949         old_ctx = ieee80211_vif_get_chanctx(sdata);
 950
 951         if (WARN_ON(!sdata->reserved_ready))
 952                 return -EBUSY;
 953
 954         if (WARN_ON(!new_ctx))
 955                 return -EINVAL;
 956
 957         if (WARN_ON(!old_ctx))
 958                 return -EINVAL;
 959
 960         if (WARN_ON(new_ctx->replace_state ==
 961                     IEEE80211_CHANCTX_REPLACES_OTHER))
 962                 return -EINVAL;
 963
 964         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
 965                                 &sdata->reserved_chandef);
 966         if (WARN_ON(!chandef))
 967                 return -EINVAL;
 968
 969         vif_chsw[0].vif = &sdata->vif;
 970         vif_chsw[0].old_ctx = &old_ctx->conf;
 971         vif_chsw[0].new_ctx = &new_ctx->conf;
 972
 973         list_del(&sdata->reserved_chanctx_list);
 974         sdata->reserved_chanctx = NULL;
 975
 976         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
 977                                      CHANCTX_SWMODE_REASSIGN_VIF);
 978         if (err) {
 979                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
 980                         ieee80211_free_chanctx(local, new_ctx);
 981
 982                 goto out;
 983         }
 984
 985         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
 986         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
 987
 988         if (sdata->vif.type == NL80211_IFTYPE_AP)
 989                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
 990
 991         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
 992                 ieee80211_free_chanctx(local, old_ctx);
 993
 994         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
 995                 changed = BSS_CHANGED_BANDWIDTH;
 996
 997         sdata->vif.bss_conf.chandef = sdata->reserved_chandef;
 998
 999         if (changed)
1000                 ieee80211_bss_info_change_notify(sdata, changed);
1001
1002 out:
1003         ieee80211_vif_chanctx_reservation_complete(sdata);
1004         return err;
1005 }
1006
1007 static int
1008 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1009 {
1010         struct ieee80211_local *local = sdata->local;
1011         struct ieee80211_chanctx *old_ctx, *new_ctx;
1012         const struct cfg80211_chan_def *chandef;
1013         int err;
1014
1015         old_ctx = ieee80211_vif_get_chanctx(sdata);
1016         new_ctx = sdata->reserved_chanctx;
1017
1018         if (WARN_ON(!sdata->reserved_ready))
1019                 return -EINVAL;
1020
1021         if (WARN_ON(old_ctx))
1022                 return -EINVAL;
1023
1024         if (WARN_ON(!new_ctx))
1025                 return -EINVAL;
1026
1027         if (WARN_ON(new_ctx->replace_state ==
1028                     IEEE80211_CHANCTX_REPLACES_OTHER))
1029                 return -EINVAL;
1030
1031         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1032                                 &sdata->reserved_chandef);
1033         if (WARN_ON(!chandef))
1034                 return -EINVAL;
1035
1036         list_del(&sdata->reserved_chanctx_list);
1037         sdata->reserved_chanctx = NULL;
1038
1039         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1040         if (err) {
1041                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1042                         ieee80211_free_chanctx(local, new_ctx);
1043
1044                 goto out;
1045         }
1046
1047 out:
1048         ieee80211_vif_chanctx_reservation_complete(sdata);
1049         return err;
1050 }
1051
1052 static bool
1053 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1054 {
1055         struct ieee80211_chanctx *old_ctx, *new_ctx;
1056
1057         lockdep_assert_held(&sdata->local->chanctx_mtx);
1058
1059         new_ctx = sdata->reserved_chanctx;
1060         old_ctx = ieee80211_vif_get_chanctx(sdata);
1061
1062         if (!old_ctx)
1063                 return false;
1064
1065         if (WARN_ON(!new_ctx))
1066                 return false;
1067
1068         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1069                 return false;
1070
1071         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1072                 return false;
1073
1074         return true;
1075 }
1076
1077 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1078                                         struct ieee80211_chanctx *new_ctx)
1079 {
1080         const struct cfg80211_chan_def *chandef;
1081
1082         lockdep_assert_held(&local->mtx);
1083         lockdep_assert_held(&local->chanctx_mtx);
1084
1085         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1086         if (WARN_ON(!chandef))
1087                 return -EINVAL;
1088
1089         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1090         local->_oper_chandef = *chandef;
1091         ieee80211_hw_config(local, 0);
1092
1093         return 0;
1094 }
1095
1096 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1097                                       int n_vifs)
1098 {
1099         struct ieee80211_vif_chanctx_switch *vif_chsw;
1100         struct ieee80211_sub_if_data *sdata;
1101         struct ieee80211_chanctx *ctx, *old_ctx;
1102         int i, err;
1103
1104         lockdep_assert_held(&local->mtx);
1105         lockdep_assert_held(&local->chanctx_mtx);
1106
1107         vif_chsw = kzalloc(sizeof(vif_chsw[0]) * n_vifs, GFP_KERNEL);
1108         if (!vif_chsw)
1109                 return -ENOMEM;
1110
1111         i = 0;
1112         list_for_each_entry(ctx, &local->chanctx_list, list) {
1113                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1114                         continue;
1115
1116                 if (WARN_ON(!ctx->replace_ctx)) {
1117                         err = -EINVAL;
1118                         goto out;
1119                 }
1120
1121                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1122                                     reserved_chanctx_list) {
1123                         if (!ieee80211_vif_has_in_place_reservation(
1124                                         sdata))
1125                                 continue;
1126
1127                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1128                         vif_chsw[i].vif = &sdata->vif;
1129                         vif_chsw[i].old_ctx = &old_ctx->conf;
1130                         vif_chsw[i].new_ctx = &ctx->conf;
1131
1132                         i++;
1133                 }
1134         }
1135
1136         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1137                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1138
1139 out:
1140         kfree(vif_chsw);
1141         return err;
1142 }
1143
1144 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1145 {
1146         struct ieee80211_chanctx *ctx;
1147         int err;
1148
1149         lockdep_assert_held(&local->mtx);
1150         lockdep_assert_held(&local->chanctx_mtx);
1151
1152         list_for_each_entry(ctx, &local->chanctx_list, list) {
1153                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1154                         continue;
1155
1156                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1157                         continue;
1158
1159                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1160                 err = ieee80211_add_chanctx(local, ctx);
1161                 if (err)
1162                         goto err;
1163         }
1164
1165         return 0;
1166
1167 err:
1168         WARN_ON(ieee80211_add_chanctx(local, ctx));
1169         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1170                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1171                         continue;
1172
1173                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1174                         continue;
1175
1176                 ieee80211_del_chanctx(local, ctx);
1177                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1178         }
1179
1180         return err;
1181 }
1182
1183 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1184 {
1185         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1186         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1187         struct ieee80211_chanctx *new_ctx = NULL;
1188         int i, err, n_assigned, n_reserved, n_ready;
1189         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1190
1191         lockdep_assert_held(&local->mtx);
1192         lockdep_assert_held(&local->chanctx_mtx);
1193
1194         /*
1195          * If there are 2 independent pairs of channel contexts performing
1196          * cross-switch of their vifs this code will still wait until both are
1197          * ready even though it could be possible to switch one before the
1198          * other is ready.
1199          *
1200          * For practical reasons and code simplicity just do a single huge
1201          * switch.
1202          */
1203
1204         /*
1205          * Verify if the reservation is still feasible.
1206          *  - if it's not then disconnect
1207          *  - if it is but not all vifs necessary are ready then defer
1208          */
1209
1210         list_for_each_entry(ctx, &local->chanctx_list, list) {
1211                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1212                         continue;
1213
1214                 if (WARN_ON(!ctx->replace_ctx)) {
1215                         err = -EINVAL;
1216                         goto err;
1217                 }
1218
1219                 if (!local->use_chanctx)
1220                         new_ctx = ctx;
1221
1222                 n_ctx++;
1223
1224                 n_assigned = 0;
1225                 n_reserved = 0;
1226                 n_ready = 0;
1227
1228                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1229                                     assigned_chanctx_list) {
1230                         n_assigned++;
1231                         if (sdata->reserved_chanctx) {
1232                                 n_reserved++;
1233                                 if (sdata->reserved_ready)
1234                                         n_ready++;
1235                         }
1236                 }
1237
1238                 if (n_assigned != n_reserved) {
1239                         if (n_ready == n_reserved) {
1240                                 wiphy_info(local->hw.wiphy,
1241                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1242                                 err = -EBUSY;
1243                                 goto err;
1244                         }
1245
1246                         return -EAGAIN;
1247                 }
1248
1249                 ctx->conf.radar_enabled = false;
1250                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1251                                     reserved_chanctx_list) {
1252                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1253                             !sdata->reserved_ready)
1254                                 return -EAGAIN;
1255
1256                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1257                         if (old_ctx) {
1258                                 if (old_ctx->replace_state ==
1259                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1260                                         n_vifs_switch++;
1261                                 else
1262                                         n_vifs_assign++;
1263                         } else {
1264                                 n_vifs_ctxless++;
1265                         }
1266
1267                         if (sdata->reserved_radar_required)
1268                                 ctx->conf.radar_enabled = true;
1269                 }
1270         }
1271
1272         if (WARN_ON(n_ctx == 0) ||
1273             WARN_ON(n_vifs_switch == 0 &&
1274                     n_vifs_assign == 0 &&
1275                     n_vifs_ctxless == 0) ||
1276             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1277             WARN_ON(!new_ctx && !local->use_chanctx)) {
1278                 err = -EINVAL;
1279                 goto err;
1280         }
1281
1282         /*
1283          * All necessary vifs are ready. Perform the switch now depending on
1284          * reservations and driver capabilities.
1285          */
1286
1287         if (local->use_chanctx) {
1288                 if (n_vifs_switch > 0) {
1289                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1290                         if (err)
1291                                 goto err;
1292                 }
1293
1294                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1295                         err = ieee80211_chsw_switch_ctxs(local);
1296                         if (err)
1297                                 goto err;
1298                 }
1299         } else {
1300                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1301                 if (err)
1302                         goto err;
1303         }
1304
1305         /*
1306          * Update all structures, values and pointers to point to new channel
1307          * context(s).
1308          */
1309
1310         i = 0;
1311         list_for_each_entry(ctx, &local->chanctx_list, list) {
1312                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1313                         continue;
1314
1315                 if (WARN_ON(!ctx->replace_ctx)) {
1316                         err = -EINVAL;
1317                         goto err;
1318                 }
1319
1320                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1321                                     reserved_chanctx_list) {
1322                         u32 changed = 0;
1323
1324                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1325                                 continue;
1326
1327                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1328
1329                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1330                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1331                                                                       false);
1332
1333                         sdata->radar_required = sdata->reserved_radar_required;
1334
1335                         if (sdata->vif.bss_conf.chandef.width !=
1336                             sdata->reserved_chandef.width)
1337                                 changed = BSS_CHANGED_BANDWIDTH;
1338
1339                         sdata->vif.bss_conf.chandef = sdata->reserved_chandef;
1340                         if (changed)
1341                                 ieee80211_bss_info_change_notify(sdata,
1342                                                                  changed);
1343
1344                         ieee80211_recalc_txpower(sdata);
1345                 }
1346
1347                 ieee80211_recalc_chanctx_chantype(local, ctx);
1348                 ieee80211_recalc_smps_chanctx(local, ctx);
1349                 ieee80211_recalc_radar_chanctx(local, ctx);
1350                 ieee80211_recalc_chanctx_min_def(local, ctx);
1351
1352                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1353                                          reserved_chanctx_list) {
1354                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1355                                 continue;
1356
1357                         list_del(&sdata->reserved_chanctx_list);
1358                         list_move(&sdata->assigned_chanctx_list,
1359                                   &ctx->assigned_vifs);
1360                         sdata->reserved_chanctx = NULL;
1361
1362                         ieee80211_vif_chanctx_reservation_complete(sdata);
1363                 }
1364
1365                 /*
1366                  * This context might have been a dependency for an already
1367                  * ready re-assign reservation interface that was deferred. Do
1368                  * not propagate error to the caller though. The in-place
1369                  * reservation for originally requested interface has already
1370                  * succeeded at this point.
1371                  */
1372                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1373                                          reserved_chanctx_list) {
1374                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1375                                         sdata)))
1376                                 continue;
1377
1378                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1379                                 continue;
1380
1381                         if (!sdata->reserved_ready)
1382                                 continue;
1383
1384                         if (ieee80211_vif_get_chanctx(sdata))
1385                                 err = ieee80211_vif_use_reserved_reassign(
1386                                                 sdata);
1387                         else
1388                                 err = ieee80211_vif_use_reserved_assign(sdata);
1389
1390                         if (err) {
1391                                 sdata_info(sdata,
1392                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1393                                            err);
1394                                 ieee80211_vif_unreserve_chanctx(sdata);
1395                                 cfg80211_stop_iface(local->hw.wiphy,
1396                                                     &sdata->wdev,
1397                                                     GFP_KERNEL);
1398                         }
1399                 }
1400         }
1401
1402         /*
1403          * Finally free old contexts
1404          */
1405
1406         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1407                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1408                         continue;
1409
1410                 ctx->replace_ctx->replace_ctx = NULL;
1411                 ctx->replace_ctx->replace_state =
1412                                 IEEE80211_CHANCTX_REPLACE_NONE;
1413
1414                 list_del_rcu(&ctx->list);
1415                 kfree_rcu(ctx, rcu_head);
1416         }
1417
1418         return 0;
1419
1420 err:
1421         list_for_each_entry(ctx, &local->chanctx_list, list) {
1422                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1423                         continue;
1424
1425                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1426                                          reserved_chanctx_list) {
1427                         ieee80211_vif_unreserve_chanctx(sdata);
1428                         ieee80211_vif_chanctx_reservation_complete(sdata);
1429                 }
1430         }
1431
1432         return err;
1433 }
1434
1435 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1436 {
1437         struct ieee80211_local *local = sdata->local;
1438         struct ieee80211_chanctx_conf *conf;
1439         struct ieee80211_chanctx *ctx;
1440         bool use_reserved_switch = false;
1441
1442         lockdep_assert_held(&local->chanctx_mtx);
1443
1444         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1445                                          lockdep_is_held(&local->chanctx_mtx));
1446         if (!conf)
1447                 return;
1448
1449         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1450
1451         if (sdata->reserved_chanctx) {
1452                 if (sdata->reserved_chanctx->replace_state ==
1453                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1454                     ieee80211_chanctx_num_reserved(local,
1455                                                    sdata->reserved_chanctx) > 1)
1456                         use_reserved_switch = true;
1457
1458                 ieee80211_vif_unreserve_chanctx(sdata);
1459         }
1460
1461         ieee80211_assign_vif_chanctx(sdata, NULL);
1462         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1463                 ieee80211_free_chanctx(local, ctx);
1464
1465         /* Unreserving may ready an in-place reservation. */
1466         if (use_reserved_switch)
1467                 ieee80211_vif_use_reserved_switch(local);
1468 }
1469
1470 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1471                               const struct cfg80211_chan_def *chandef,
1472                               enum ieee80211_chanctx_mode mode)
1473 {
1474         struct ieee80211_local *local = sdata->local;
1475         struct ieee80211_chanctx *ctx;
1476         u8 radar_detect_width = 0;
1477         int ret;
1478
1479         lockdep_assert_held(&local->mtx);
1480
1481         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1482
1483         mutex_lock(&local->chanctx_mtx);
1484
1485         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1486                                             chandef,
1487                                             sdata->wdev.iftype);
1488         if (ret < 0)
1489                 goto out;
1490         if (ret > 0)
1491                 radar_detect_width = BIT(chandef->width);
1492
1493         sdata->radar_required = ret;
1494
1495         ret = ieee80211_check_combinations(sdata, chandef, mode,
1496                                            radar_detect_width);
1497         if (ret < 0)
1498                 goto out;
1499
1500         __ieee80211_vif_release_channel(sdata);
1501
1502         ctx = ieee80211_find_chanctx(local, chandef, mode);
1503         if (!ctx)
1504                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1505         if (IS_ERR(ctx)) {
1506                 ret = PTR_ERR(ctx);
1507                 goto out;
1508         }
1509
1510         sdata->vif.bss_conf.chandef = *chandef;
1511
1512         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1513         if (ret) {
1514                 /* if assign fails refcount stays the same */
1515                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1516                         ieee80211_free_chanctx(local, ctx);
1517                 goto out;
1518         }
1519
1520         ieee80211_recalc_smps_chanctx(local, ctx);
1521         ieee80211_recalc_radar_chanctx(local, ctx);
1522  out:
1523         mutex_unlock(&local->chanctx_mtx);
1524         return ret;
1525 }
1526
1527 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1528 {
1529         struct ieee80211_local *local = sdata->local;
1530         struct ieee80211_chanctx *new_ctx;
1531         struct ieee80211_chanctx *old_ctx;
1532         int err;
1533
1534         lockdep_assert_held(&local->mtx);
1535         lockdep_assert_held(&local->chanctx_mtx);
1536
1537         new_ctx = sdata->reserved_chanctx;
1538         old_ctx = ieee80211_vif_get_chanctx(sdata);
1539
1540         if (WARN_ON(!new_ctx))
1541                 return -EINVAL;
1542
1543         if (WARN_ON(new_ctx->replace_state ==
1544                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1545                 return -EINVAL;
1546
1547         if (WARN_ON(sdata->reserved_ready))
1548                 return -EINVAL;
1549
1550         sdata->reserved_ready = true;
1551
1552         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1553                 if (old_ctx)
1554                         err = ieee80211_vif_use_reserved_reassign(sdata);
1555                 else
1556                         err = ieee80211_vif_use_reserved_assign(sdata);
1557
1558                 if (err)
1559                         return err;
1560         }
1561
1562         /*
1563          * In-place reservation may need to be finalized now either if:
1564          *  a) sdata is taking part in the swapping itself and is the last one
1565          *  b) sdata has switched with a re-assign reservation to an existing
1566          *     context readying in-place switching of old_ctx
1567          *
1568          * In case of (b) do not propagate the error up because the requested
1569          * sdata already switched successfully. Just spill an extra warning.
1570          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1571          * interfaces upon failure.
1572          */
1573         if ((old_ctx &&
1574              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1575             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1576                 err = ieee80211_vif_use_reserved_switch(local);
1577                 if (err && err != -EAGAIN) {
1578                         if (new_ctx->replace_state ==
1579                             IEEE80211_CHANCTX_REPLACES_OTHER)
1580                                 return err;
1581
1582                         wiphy_info(local->hw.wiphy,
1583                                    "depending in-place reservation failed (err=%d)\n",
1584                                    err);
1585                 }
1586         }
1587
1588         return 0;
1589 }
1590
1591 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1592                                    const struct cfg80211_chan_def *chandef,
1593                                    u32 *changed)
1594 {
1595         struct ieee80211_local *local = sdata->local;
1596         struct ieee80211_chanctx_conf *conf;
1597         struct ieee80211_chanctx *ctx;
1598         const struct cfg80211_chan_def *compat;
1599         int ret;
1600
1601         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1602                                      IEEE80211_CHAN_DISABLED))
1603                 return -EINVAL;
1604
1605         mutex_lock(&local->chanctx_mtx);
1606         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1607                 ret = 0;
1608                 goto out;
1609         }
1610
1611         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1612             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1613                 ret = -EINVAL;
1614                 goto out;
1615         }
1616
1617         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1618                                          lockdep_is_held(&local->chanctx_mtx));
1619         if (!conf) {
1620                 ret = -EINVAL;
1621                 goto out;
1622         }
1623
1624         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1625
1626         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1627         if (!compat) {
1628                 ret = -EINVAL;
1629                 goto out;
1630         }
1631
1632         switch (ctx->replace_state) {
1633         case IEEE80211_CHANCTX_REPLACE_NONE:
1634                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1635                         ret = -EBUSY;
1636                         goto out;
1637                 }
1638                 break;
1639         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1640                 /* TODO: Perhaps the bandwidth change could be treated as a
1641                  * reservation itself? */
1642                 ret = -EBUSY;
1643                 goto out;
1644         case IEEE80211_CHANCTX_REPLACES_OTHER:
1645                 /* channel context that is going to replace another channel
1646                  * context doesn't really exist and shouldn't be assigned
1647                  * anywhere yet */
1648                 WARN_ON(1);
1649                 break;
1650         }
1651
1652         sdata->vif.bss_conf.chandef = *chandef;
1653
1654         ieee80211_recalc_chanctx_chantype(local, ctx);
1655
1656         *changed |= BSS_CHANGED_BANDWIDTH;
1657         ret = 0;
1658  out:
1659         mutex_unlock(&local->chanctx_mtx);
1660         return ret;
1661 }
1662
1663 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1664 {
1665         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1666
1667         lockdep_assert_held(&sdata->local->mtx);
1668
1669         mutex_lock(&sdata->local->chanctx_mtx);
1670         __ieee80211_vif_release_channel(sdata);
1671         mutex_unlock(&sdata->local->chanctx_mtx);
1672 }
1673
1674 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1675 {
1676         struct ieee80211_local *local = sdata->local;
1677         struct ieee80211_sub_if_data *ap;
1678         struct ieee80211_chanctx_conf *conf;
1679
1680         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1681                 return;
1682
1683         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1684
1685         mutex_lock(&local->chanctx_mtx);
1686
1687         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1688                                          lockdep_is_held(&local->chanctx_mtx));
1689         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1690         mutex_unlock(&local->chanctx_mtx);
1691 }
1692
1693 void ieee80211_iter_chan_contexts_atomic(
1694         struct ieee80211_hw *hw,
1695         void (*iter)(struct ieee80211_hw *hw,
1696                      struct ieee80211_chanctx_conf *chanctx_conf,
1697                      void *data),
1698         void *iter_data)
1699 {
1700         struct ieee80211_local *local = hw_to_local(hw);
1701         struct ieee80211_chanctx *ctx;
1702
1703         rcu_read_lock();
1704         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1705                 if (ctx->driver_present)
1706                         iter(hw, &ctx->conf, iter_data);
1707         rcu_read_unlock();
1708 }
1709 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);