net/mac80211/offchannel.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Off-channel operation helpers
   4  *
   5  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
   6  * Copyright 2004, Instant802 Networks, Inc.
   7  * Copyright 2005, Devicescape Software, Inc.
   8  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   9  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
  10  * Copyright 2009       Johannes Berg <johannes@sipsolutions.net>
  11  * Copyright (C) 2019 Intel Corporation
  12  */
  13 #include <linux/export.h>
  14 #include <net/mac80211.h>
  15 #include "ieee80211_i.h"
  16 #include "driver-ops.h"
  17
  18 /*
  19  * Tell our hardware to disable PS.
  20  * Optionally inform AP that we will go to sleep so that it will buffer
  21  * the frames while we are doing off-channel work.  This is optional
  22  * because we *may* be doing work on-operating channel, and want our
  23  * hardware unconditionally awake, but still let the AP send us normal frames.
  24  */
  25 static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
  26 {
  27         struct ieee80211_local *local = sdata->local;
  28         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
  29         bool offchannel_ps_enabled = false;
  30
  31         /* FIXME: what to do when local->pspolling is true? */
  32
  33         del_timer_sync(&local->dynamic_ps_timer);
  34         del_timer_sync(&ifmgd->bcn_mon_timer);
  35         del_timer_sync(&ifmgd->conn_mon_timer);
  36
  37         cancel_work_sync(&local->dynamic_ps_enable_work);
  38
  39         if (local->hw.conf.flags & IEEE80211_CONF_PS) {
  40                 offchannel_ps_enabled = true;
  41                 local->hw.conf.flags &= ~IEEE80211_CONF_PS;
  42                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
  43         }
  44
  45         if (!offchannel_ps_enabled ||
  46             !ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
  47                 /*
  48                  * If power save was enabled, no need to send a nullfunc
  49                  * frame because AP knows that we are sleeping. But if the
  50                  * hardware is creating the nullfunc frame for power save
  51                  * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
  52                  * enabled) and power save was enabled, the firmware just
  53                  * sent a null frame with power save disabled. So we need
  54                  * to send a new nullfunc frame to inform the AP that we
  55                  * are again sleeping.
  56                  */
  57                 ieee80211_send_nullfunc(local, sdata, true);
  58 }
  59
  60 /* inform AP that we are awake again */
  61 static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
  62 {
  63         struct ieee80211_local *local = sdata->local;
  64
  65         if (!local->ps_sdata)
  66                 ieee80211_send_nullfunc(local, sdata, false);
  67         else if (local->hw.conf.dynamic_ps_timeout > 0) {
  68                 /*
  69                  * the dynamic_ps_timer had been running before leaving the
  70                  * operating channel, restart the timer now and send a nullfunc
  71                  * frame to inform the AP that we are awake so that AP sends
  72                  * the buffered packets (if any).
  73                  */
  74                 ieee80211_send_nullfunc(local, sdata, false);
  75                 mod_timer(&local->dynamic_ps_timer, jiffies +
  76                           msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
  77         }
  78
  79         ieee80211_sta_reset_beacon_monitor(sdata);
  80         ieee80211_sta_reset_conn_monitor(sdata);
  81 }
  82
  83 void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
  84 {
  85         struct ieee80211_sub_if_data *sdata;
  86
  87         if (WARN_ON(local->use_chanctx))
  88                 return;
  89
  90         /*
  91          * notify the AP about us leaving the channel and stop all
  92          * STA interfaces.
  93          */
  94
  95         /*
  96          * Stop queues and transmit all frames queued by the driver
  97          * before sending nullfunc to enable powersave at the AP.
  98          */
  99         ieee80211_stop_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
 100                                         IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
 101                                         false);
 102         ieee80211_flush_queues(local, NULL, false);
 103
 104         mutex_lock(&local->iflist_mtx);
 105         list_for_each_entry(sdata, &local->interfaces, list) {
 106                 if (!ieee80211_sdata_running(sdata))
 107                         continue;
 108
 109                 if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE ||
 110                     sdata->vif.type == NL80211_IFTYPE_NAN)
 111                         continue;
 112
 113                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 114                         set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
 115
 116                 /* Check to see if we should disable beaconing. */
 117                 if (sdata->vif.bss_conf.enable_beacon) {
 118                         set_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
 119                                 &sdata->state);
 120                         sdata->vif.bss_conf.enable_beacon = false;
 121                         ieee80211_bss_info_change_notify(
 122                                 sdata, BSS_CHANGED_BEACON_ENABLED);
 123                 }
 124
 125                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 126                     sdata->u.mgd.associated)
 127                         ieee80211_offchannel_ps_enable(sdata);
 128         }
 129         mutex_unlock(&local->iflist_mtx);
 130 }
 131
 132 void ieee80211_offchannel_return(struct ieee80211_local *local)
 133 {
 134         struct ieee80211_sub_if_data *sdata;
 135
 136         if (WARN_ON(local->use_chanctx))
 137                 return;
 138
 139         mutex_lock(&local->iflist_mtx);
 140         list_for_each_entry(sdata, &local->interfaces, list) {
 141                 if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
 142                         continue;
 143
 144                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 145                         clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
 146
 147                 if (!ieee80211_sdata_running(sdata))
 148                         continue;
 149
 150                 /* Tell AP we're back */
 151                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 152                     sdata->u.mgd.associated)
 153                         ieee80211_offchannel_ps_disable(sdata);
 154
 155                 if (test_and_clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
 156                                        &sdata->state)) {
 157                         sdata->vif.bss_conf.enable_beacon = true;
 158                         ieee80211_bss_info_change_notify(
 159                                 sdata, BSS_CHANGED_BEACON_ENABLED);
 160                 }
 161         }
 162         mutex_unlock(&local->iflist_mtx);
 163
 164         ieee80211_wake_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
 165                                         IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
 166                                         false);
 167 }
 168
 169 static void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc)
 170 {
 171         /* was never transmitted */
 172         if (roc->frame) {
 173                 cfg80211_mgmt_tx_status(&roc->sdata->wdev, roc->mgmt_tx_cookie,
 174                                         roc->frame->data, roc->frame->len,
 175                                         false, GFP_KERNEL);
 176                 ieee80211_free_txskb(&roc->sdata->local->hw, roc->frame);
 177         }
 178
 179         if (!roc->mgmt_tx_cookie)
 180                 cfg80211_remain_on_channel_expired(&roc->sdata->wdev,
 181                                                    roc->cookie, roc->chan,
 182                                                    GFP_KERNEL);
 183         else
 184                 cfg80211_tx_mgmt_expired(&roc->sdata->wdev,
 185                                          roc->mgmt_tx_cookie,
 186                                          roc->chan, GFP_KERNEL);
 187
 188         list_del(&roc->list);
 189         kfree(roc);
 190 }
 191
 192 static unsigned long ieee80211_end_finished_rocs(struct ieee80211_local *local,
 193                                                  unsigned long now)
 194 {
 195         struct ieee80211_roc_work *roc, *tmp;
 196         long remaining_dur_min = LONG_MAX;
 197
 198         lockdep_assert_held(&local->mtx);
 199
 200         list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
 201                 long remaining;
 202
 203                 if (!roc->started)
 204                         break;
 205
 206                 remaining = roc->start_time +
 207                             msecs_to_jiffies(roc->duration) -
 208                             now;
 209
 210                 /* In case of HW ROC, it is possible that the HW finished the
 211                  * ROC session before the actual requested time. In such a case
 212                  * end the ROC session (disregarding the remaining time).
 213                  */
 214                 if (roc->abort || roc->hw_begun || remaining <= 0)
 215                         ieee80211_roc_notify_destroy(roc);
 216                 else
 217                         remaining_dur_min = min(remaining_dur_min, remaining);
 218         }
 219
 220         return remaining_dur_min;
 221 }
 222
 223 static bool ieee80211_recalc_sw_work(struct ieee80211_local *local,
 224                                      unsigned long now)
 225 {
 226         long dur = ieee80211_end_finished_rocs(local, now);
 227
 228         if (dur == LONG_MAX)
 229                 return false;
 230
 231         mod_delayed_work(local->workqueue, &local->roc_work, dur);
 232         return true;
 233 }
 234
 235 static void ieee80211_handle_roc_started(struct ieee80211_roc_work *roc,
 236                                          unsigned long start_time)
 237 {
 238         if (WARN_ON(roc->notified))
 239                 return;
 240
 241         roc->start_time = start_time;
 242         roc->started = true;
 243
 244         if (roc->mgmt_tx_cookie) {
 245                 if (!WARN_ON(!roc->frame)) {
 246                         ieee80211_tx_skb_tid_band(roc->sdata, roc->frame, 7,
 247                                                   roc->chan->band);
 248                         roc->frame = NULL;
 249                 }
 250         } else {
 251                 cfg80211_ready_on_channel(&roc->sdata->wdev, roc->cookie,
 252                                           roc->chan, roc->req_duration,
 253                                           GFP_KERNEL);
 254         }
 255
 256         roc->notified = true;
 257 }
 258
 259 static void ieee80211_hw_roc_start(struct work_struct *work)
 260 {
 261         struct ieee80211_local *local =
 262                 container_of(work, struct ieee80211_local, hw_roc_start);
 263         struct ieee80211_roc_work *roc;
 264
 265         mutex_lock(&local->mtx);
 266
 267         list_for_each_entry(roc, &local->roc_list, list) {
 268                 if (!roc->started)
 269                         break;
 270
 271                 roc->hw_begun = true;
 272                 ieee80211_handle_roc_started(roc, local->hw_roc_start_time);
 273         }
 274
 275         mutex_unlock(&local->mtx);
 276 }
 277
 278 void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
 279 {
 280         struct ieee80211_local *local = hw_to_local(hw);
 281
 282         local->hw_roc_start_time = jiffies;
 283
 284         trace_api_ready_on_channel(local);
 285
 286         ieee80211_queue_work(hw, &local->hw_roc_start);
 287 }
 288 EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
 289
 290 static void _ieee80211_start_next_roc(struct ieee80211_local *local)
 291 {
 292         struct ieee80211_roc_work *roc, *tmp;
 293         enum ieee80211_roc_type type;
 294         u32 min_dur, max_dur;
 295
 296         lockdep_assert_held(&local->mtx);
 297
 298         if (WARN_ON(list_empty(&local->roc_list)))
 299                 return;
 300
 301         roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
 302                                list);
 303
 304         if (WARN_ON(roc->started))
 305                 return;
 306
 307         min_dur = roc->duration;
 308         max_dur = roc->duration;
 309         type = roc->type;
 310
 311         list_for_each_entry(tmp, &local->roc_list, list) {
 312                 if (tmp == roc)
 313                         continue;
 314                 if (tmp->sdata != roc->sdata || tmp->chan != roc->chan)
 315                         break;
 316                 max_dur = max(tmp->duration, max_dur);
 317                 min_dur = min(tmp->duration, min_dur);
 318                 type = max(tmp->type, type);
 319         }
 320
 321         if (local->ops->remain_on_channel) {
 322                 int ret = drv_remain_on_channel(local, roc->sdata, roc->chan,
 323                                                 max_dur, type);
 324
 325                 if (ret) {
 326                         wiphy_warn(local->hw.wiphy,
 327                                    "failed to start next HW ROC (%d)\n", ret);
 328                         /*
 329                          * queue the work struct again to avoid recursion
 330                          * when multiple failures occur
 331                          */
 332                         list_for_each_entry(tmp, &local->roc_list, list) {
 333                                 if (tmp->sdata != roc->sdata ||
 334                                     tmp->chan != roc->chan)
 335                                         break;
 336                                 tmp->started = true;
 337                                 tmp->abort = true;
 338                         }
 339                         ieee80211_queue_work(&local->hw, &local->hw_roc_done);
 340                         return;
 341                 }
 342
 343                 /* we'll notify about the start once the HW calls back */
 344                 list_for_each_entry(tmp, &local->roc_list, list) {
 345                         if (tmp->sdata != roc->sdata || tmp->chan != roc->chan)
 346                                 break;
 347                         tmp->started = true;
 348                 }
 349         } else {
 350                 /* If actually operating on the desired channel (with at least
 351                  * 20 MHz channel width) don't stop all the operations but still
 352                  * treat it as though the ROC operation started properly, so
 353                  * other ROC operations won't interfere with this one.
 354                  */
 355                 roc->on_channel = roc->chan == local->_oper_chandef.chan &&
 356                                   local->_oper_chandef.width != NL80211_CHAN_WIDTH_5 &&
 357                                   local->_oper_chandef.width != NL80211_CHAN_WIDTH_10;
 358
 359                 /* start this ROC */
 360                 ieee80211_recalc_idle(local);
 361
 362                 if (!roc->on_channel) {
 363                         ieee80211_offchannel_stop_vifs(local);
 364
 365                         local->tmp_channel = roc->chan;
 366                         ieee80211_hw_config(local, 0);
 367                 }
 368
 369                 ieee80211_queue_delayed_work(&local->hw, &local->roc_work,
 370                                              msecs_to_jiffies(min_dur));
 371
 372                 /* tell userspace or send frame(s) */
 373                 list_for_each_entry(tmp, &local->roc_list, list) {
 374                         if (tmp->sdata != roc->sdata || tmp->chan != roc->chan)
 375                                 break;
 376
 377                         tmp->on_channel = roc->on_channel;
 378                         ieee80211_handle_roc_started(tmp, jiffies);
 379                 }
 380         }
 381 }
 382
 383 void ieee80211_start_next_roc(struct ieee80211_local *local)
 384 {
 385         struct ieee80211_roc_work *roc;
 386
 387         lockdep_assert_held(&local->mtx);
 388
 389         if (list_empty(&local->roc_list)) {
 390                 ieee80211_run_deferred_scan(local);
 391                 return;
 392         }
 393
 394         /* defer roc if driver is not started (i.e. during reconfig) */
 395         if (local->in_reconfig)
 396                 return;
 397
 398         roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
 399                                list);
 400
 401         if (WARN_ON_ONCE(roc->started))
 402                 return;
 403
 404         if (local->ops->remain_on_channel) {
 405                 _ieee80211_start_next_roc(local);
 406         } else {
 407                 /* delay it a bit */
 408                 ieee80211_queue_delayed_work(&local->hw, &local->roc_work,
 409                                              round_jiffies_relative(HZ/2));
 410         }
 411 }
 412
 413 static void __ieee80211_roc_work(struct ieee80211_local *local)
 414 {
 415         struct ieee80211_roc_work *roc;
 416         bool on_channel;
 417
 418         lockdep_assert_held(&local->mtx);
 419
 420         if (WARN_ON(local->ops->remain_on_channel))
 421                 return;
 422
 423         roc = list_first_entry_or_null(&local->roc_list,
 424                                        struct ieee80211_roc_work, list);
 425         if (!roc)
 426                 return;
 427
 428         if (!roc->started) {
 429                 WARN_ON(local->use_chanctx);
 430                 _ieee80211_start_next_roc(local);
 431         } else {
 432                 on_channel = roc->on_channel;
 433                 if (ieee80211_recalc_sw_work(local, jiffies))
 434                         return;
 435
 436                 /* careful - roc pointer became invalid during recalc */
 437
 438                 if (!on_channel) {
 439                         ieee80211_flush_queues(local, NULL, false);
 440
 441                         local->tmp_channel = NULL;
 442                         ieee80211_hw_config(local, 0);
 443
 444                         ieee80211_offchannel_return(local);
 445                 }
 446
 447                 ieee80211_recalc_idle(local);
 448                 ieee80211_start_next_roc(local);
 449         }
 450 }
 451
 452 static void ieee80211_roc_work(struct work_struct *work)
 453 {
 454         struct ieee80211_local *local =
 455                 container_of(work, struct ieee80211_local, roc_work.work);
 456
 457         mutex_lock(&local->mtx);
 458         __ieee80211_roc_work(local);
 459         mutex_unlock(&local->mtx);
 460 }
 461
 462 static void ieee80211_hw_roc_done(struct work_struct *work)
 463 {
 464         struct ieee80211_local *local =
 465                 container_of(work, struct ieee80211_local, hw_roc_done);
 466
 467         mutex_lock(&local->mtx);
 468
 469         ieee80211_end_finished_rocs(local, jiffies);
 470
 471         /* if there's another roc, start it now */
 472         ieee80211_start_next_roc(local);
 473
 474         mutex_unlock(&local->mtx);
 475 }
 476
 477 void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw)
 478 {
 479         struct ieee80211_local *local = hw_to_local(hw);
 480
 481         trace_api_remain_on_channel_expired(local);
 482
 483         ieee80211_queue_work(hw, &local->hw_roc_done);
 484 }
 485 EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired);
 486
 487 static bool
 488 ieee80211_coalesce_hw_started_roc(struct ieee80211_local *local,
 489                                   struct ieee80211_roc_work *new_roc,
 490                                   struct ieee80211_roc_work *cur_roc)
 491 {
 492         unsigned long now = jiffies;
 493         unsigned long remaining;
 494
 495         if (WARN_ON(!cur_roc->started))
 496                 return false;
 497
 498         /* if it was scheduled in the hardware, but not started yet,
 499          * we can only combine if the older one had a longer duration
 500          */
 501         if (!cur_roc->hw_begun && new_roc->duration > cur_roc->duration)
 502                 return false;
 503
 504         remaining = cur_roc->start_time +
 505                     msecs_to_jiffies(cur_roc->duration) -
 506                     now;
 507
 508         /* if it doesn't fit entirely, schedule a new one */
 509         if (new_roc->duration > jiffies_to_msecs(remaining))
 510                 return false;
 511
 512         /* add just after the current one so we combine their finish later */
 513         list_add(&new_roc->list, &cur_roc->list);
 514
 515         /* if the existing one has already begun then let this one also
 516          * begin, otherwise they'll both be marked properly by the work
 517          * struct that runs once the driver notifies us of the beginning
 518          */
 519         if (cur_roc->hw_begun) {
 520                 new_roc->hw_begun = true;
 521                 ieee80211_handle_roc_started(new_roc, now);
 522         }
 523
 524         return true;
 525 }
 526
 527 static int ieee80211_start_roc_work(struct ieee80211_local *local,
 528                                     struct ieee80211_sub_if_data *sdata,
 529                                     struct ieee80211_channel *channel,
 530                                     unsigned int duration, u64 *cookie,
 531                                     struct sk_buff *txskb,
 532                                     enum ieee80211_roc_type type)
 533 {
 534         struct ieee80211_roc_work *roc, *tmp;
 535         bool queued = false, combine_started = true;
 536         int ret;
 537
 538         lockdep_assert_held(&local->mtx);
 539
 540         if (channel->freq_offset)
 541                 /* this may work, but is untested */
 542                 return -EOPNOTSUPP;
 543
 544         if (local->use_chanctx && !local->ops->remain_on_channel)
 545                 return -EOPNOTSUPP;
 546
 547         roc = kzalloc(sizeof(*roc), GFP_KERNEL);
 548         if (!roc)
 549                 return -ENOMEM;
 550
 551         /*
 552          * If the duration is zero, then the driver
 553          * wouldn't actually do anything. Set it to
 554          * 10 for now.
 555          *
 556          * TODO: cancel the off-channel operation
 557          *       when we get the SKB's TX status and
 558          *       the wait time was zero before.
 559          */
 560         if (!duration)
 561                 duration = 10;
 562
 563         roc->chan = channel;
 564         roc->duration = duration;
 565         roc->req_duration = duration;
 566         roc->frame = txskb;
 567         roc->type = type;
 568         roc->sdata = sdata;
 569
 570         /*
 571          * cookie is either the roc cookie (for normal roc)
 572          * or the SKB (for mgmt TX)
 573          */
 574         if (!txskb) {
 575                 roc->cookie = ieee80211_mgmt_tx_cookie(local);
 576                 *cookie = roc->cookie;
 577         } else {
 578                 roc->mgmt_tx_cookie = *cookie;
 579         }
 580
 581         /* if there's no need to queue, handle it immediately */
 582         if (list_empty(&local->roc_list) &&
 583             !local->scanning && !ieee80211_is_radar_required(local)) {
 584                 /* if not HW assist, just queue & schedule work */
 585                 if (!local->ops->remain_on_channel) {
 586                         list_add_tail(&roc->list, &local->roc_list);
 587                         ieee80211_queue_delayed_work(&local->hw,
 588                                                      &local->roc_work, 0);
 589                 } else {
 590                         /* otherwise actually kick it off here
 591                          * (for error handling)
 592                          */
 593                         ret = drv_remain_on_channel(local, sdata, channel,
 594                                                     duration, type);
 595                         if (ret) {
 596                                 kfree(roc);
 597                                 return ret;
 598                         }
 599                         roc->started = true;
 600                         list_add_tail(&roc->list, &local->roc_list);
 601                 }
 602
 603                 return 0;
 604         }
 605
 606         /* otherwise handle queueing */
 607
 608         list_for_each_entry(tmp, &local->roc_list, list) {
 609                 if (tmp->chan != channel || tmp->sdata != sdata)
 610                         continue;
 611
 612                 /*
 613                  * Extend this ROC if possible: If it hasn't started, add
 614                  * just after the new one to combine.
 615                  */
 616                 if (!tmp->started) {
 617                         list_add(&roc->list, &tmp->list);
 618                         queued = true;
 619                         break;
 620                 }
 621
 622                 if (!combine_started)
 623                         continue;
 624
 625                 if (!local->ops->remain_on_channel) {
 626                         /* If there's no hardware remain-on-channel, and
 627                          * doing so won't push us over the maximum r-o-c
 628                          * we allow, then we can just add the new one to
 629                          * the list and mark it as having started now.
 630                          * If it would push over the limit, don't try to
 631                          * combine with other started ones (that haven't
 632                          * been running as long) but potentially sort it
 633                          * with others that had the same fate.
 634                          */
 635                         unsigned long now = jiffies;
 636                         u32 elapsed = jiffies_to_msecs(now - tmp->start_time);
 637                         struct wiphy *wiphy = local->hw.wiphy;
 638                         u32 max_roc = wiphy->max_remain_on_channel_duration;
 639
 640                         if (elapsed + roc->duration > max_roc) {
 641                                 combine_started = false;
 642                                 continue;
 643                         }
 644
 645                         list_add(&roc->list, &tmp->list);
 646                         queued = true;
 647                         roc->on_channel = tmp->on_channel;
 648                         ieee80211_handle_roc_started(roc, now);
 649                         ieee80211_recalc_sw_work(local, now);
 650                         break;
 651                 }
 652
 653                 queued = ieee80211_coalesce_hw_started_roc(local, roc, tmp);
 654                 if (queued)
 655                         break;
 656                 /* if it wasn't queued, perhaps it can be combined with
 657                  * another that also couldn't get combined previously,
 658                  * but no need to check for already started ones, since
 659                  * that can't work.
 660                  */
 661                 combine_started = false;
 662         }
 663
 664         if (!queued)
 665                 list_add_tail(&roc->list, &local->roc_list);
 666
 667         return 0;
 668 }
 669
 670 int ieee80211_remain_on_channel(struct wiphy *wiphy, struct wireless_dev *wdev,
 671                                 struct ieee80211_channel *chan,
 672                                 unsigned int duration, u64 *cookie)
 673 {
 674         struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
 675         struct ieee80211_local *local = sdata->local;
 676         int ret;
 677
 678         mutex_lock(&local->mtx);
 679         ret = ieee80211_start_roc_work(local, sdata, chan,
 680                                        duration, cookie, NULL,
 681                                        IEEE80211_ROC_TYPE_NORMAL);
 682         mutex_unlock(&local->mtx);
 683
 684         return ret;
 685 }
 686
 687 static int ieee80211_cancel_roc(struct ieee80211_local *local,
 688                                 u64 cookie, bool mgmt_tx)
 689 {
 690         struct ieee80211_roc_work *roc, *tmp, *found = NULL;
 691         int ret;
 692
 693         if (!cookie)
 694                 return -ENOENT;
 695
 696         flush_work(&local->hw_roc_start);
 697
 698         mutex_lock(&local->mtx);
 699         list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
 700                 if (!mgmt_tx && roc->cookie != cookie)
 701                         continue;
 702                 else if (mgmt_tx && roc->mgmt_tx_cookie != cookie)
 703                         continue;
 704
 705                 found = roc;
 706                 break;
 707         }
 708
 709         if (!found) {
 710                 mutex_unlock(&local->mtx);
 711                 return -ENOENT;
 712         }
 713
 714         if (!found->started) {
 715                 ieee80211_roc_notify_destroy(found);
 716                 goto out_unlock;
 717         }
 718
 719         if (local->ops->remain_on_channel) {
 720                 ret = drv_cancel_remain_on_channel(local, roc->sdata);
 721                 if (WARN_ON_ONCE(ret)) {
 722                         mutex_unlock(&local->mtx);
 723                         return ret;
 724                 }
 725
 726                 /* TODO:
 727                  * if multiple items were combined here then we really shouldn't
 728                  * cancel them all - we should wait for as much time as needed
 729                  * for the longest remaining one, and only then cancel ...
 730                  */
 731                 list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
 732                         if (!roc->started)
 733                                 break;
 734                         if (roc == found)
 735                                 found = NULL;
 736                         ieee80211_roc_notify_destroy(roc);
 737                 }
 738
 739                 /* that really must not happen - it was started */
 740                 WARN_ON(found);
 741
 742                 ieee80211_start_next_roc(local);
 743         } else {
 744                 /* go through work struct to return to the operating channel */
 745                 found->abort = true;
 746                 mod_delayed_work(local->workqueue, &local->roc_work, 0);
 747         }
 748
 749  out_unlock:
 750         mutex_unlock(&local->mtx);
 751
 752         return 0;
 753 }
 754
 755 int ieee80211_cancel_remain_on_channel(struct wiphy *wiphy,
 756                                        struct wireless_dev *wdev, u64 cookie)
 757 {
 758         struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
 759         struct ieee80211_local *local = sdata->local;
 760
 761         return ieee80211_cancel_roc(local, cookie, false);
 762 }
 763
 764 int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
 765                       struct cfg80211_mgmt_tx_params *params, u64 *cookie)
 766 {
 767         struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
 768         struct ieee80211_local *local = sdata->local;
 769         struct sk_buff *skb;
 770         struct sta_info *sta;
 771         const struct ieee80211_mgmt *mgmt = (void *)params->buf;
 772         bool need_offchan = false;
 773         u32 flags;
 774         int ret;
 775         u8 *data;
 776
 777         if (params->dont_wait_for_ack)
 778                 flags = IEEE80211_TX_CTL_NO_ACK;
 779         else
 780                 flags = IEEE80211_TX_INTFL_NL80211_FRAME_TX |
 781                         IEEE80211_TX_CTL_REQ_TX_STATUS;
 782
 783         if (params->no_cck)
 784                 flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
 785
 786         switch (sdata->vif.type) {
 787         case NL80211_IFTYPE_ADHOC:
 788                 if (!sdata->vif.bss_conf.ibss_joined)
 789                         need_offchan = true;
 790 #ifdef CONFIG_MAC80211_MESH
 791                 fallthrough;
 792         case NL80211_IFTYPE_MESH_POINT:
 793                 if (ieee80211_vif_is_mesh(&sdata->vif) &&
 794                     !sdata->u.mesh.mesh_id_len)
 795                         need_offchan = true;
 796 #endif
 797                 fallthrough;
 798         case NL80211_IFTYPE_AP:
 799         case NL80211_IFTYPE_AP_VLAN:
 800         case NL80211_IFTYPE_P2P_GO:
 801                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 802                     !ieee80211_vif_is_mesh(&sdata->vif) &&
 803                     !rcu_access_pointer(sdata->bss->beacon))
 804                         need_offchan = true;
 805                 if (!ieee80211_is_action(mgmt->frame_control) ||
 806                     mgmt->u.action.category == WLAN_CATEGORY_PUBLIC ||
 807                     mgmt->u.action.category == WLAN_CATEGORY_SELF_PROTECTED ||
 808                     mgmt->u.action.category == WLAN_CATEGORY_SPECTRUM_MGMT)
 809                         break;
 810                 rcu_read_lock();
 811                 sta = sta_info_get_bss(sdata, mgmt->da);
 812                 rcu_read_unlock();
 813                 if (!sta)
 814                         return -ENOLINK;
 815                 break;
 816         case NL80211_IFTYPE_STATION:
 817         case NL80211_IFTYPE_P2P_CLIENT:
 818                 sdata_lock(sdata);
 819                 if (!sdata->u.mgd.associated ||
 820                     (params->offchan && params->wait &&
 821                      local->ops->remain_on_channel &&
 822                      memcmp(sdata->u.mgd.associated->bssid,
 823                             mgmt->bssid, ETH_ALEN)))
 824                         need_offchan = true;
 825                 sdata_unlock(sdata);
 826                 break;
 827         case NL80211_IFTYPE_P2P_DEVICE:
 828                 need_offchan = true;
 829                 break;
 830         case NL80211_IFTYPE_NAN:
 831         default:
 832                 return -EOPNOTSUPP;
 833         }
 834
 835         /* configurations requiring offchan cannot work if no channel has been
 836          * specified
 837          */
 838         if (need_offchan && !params->chan)
 839                 return -EINVAL;
 840
 841         mutex_lock(&local->mtx);
 842
 843         /* Check if the operating channel is the requested channel */
 844         if (!need_offchan) {
 845                 struct ieee80211_chanctx_conf *chanctx_conf;
 846
 847                 rcu_read_lock();
 848                 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 849
 850                 if (chanctx_conf) {
 851                         need_offchan = params->chan &&
 852                                        (params->chan !=
 853                                         chanctx_conf->def.chan);
 854                 } else if (!params->chan) {
 855                         ret = -EINVAL;
 856                         rcu_read_unlock();
 857                         goto out_unlock;
 858                 } else {
 859                         need_offchan = true;
 860                 }
 861                 rcu_read_unlock();
 862         }
 863
 864         if (need_offchan && !params->offchan) {
 865                 ret = -EBUSY;
 866                 goto out_unlock;
 867         }
 868
 869         skb = dev_alloc_skb(local->hw.extra_tx_headroom + params->len);
 870         if (!skb) {
 871                 ret = -ENOMEM;
 872                 goto out_unlock;
 873         }
 874         skb_reserve(skb, local->hw.extra_tx_headroom);
 875
 876         data = skb_put_data(skb, params->buf, params->len);
 877
 878         /* Update CSA counters */
 879         if (sdata->vif.csa_active &&
 880             (sdata->vif.type == NL80211_IFTYPE_AP ||
 881              sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
 882              sdata->vif.type == NL80211_IFTYPE_ADHOC) &&
 883             params->n_csa_offsets) {
 884                 int i;
 885                 struct beacon_data *beacon = NULL;
 886
 887                 rcu_read_lock();
 888
 889                 if (sdata->vif.type == NL80211_IFTYPE_AP)
 890                         beacon = rcu_dereference(sdata->u.ap.beacon);
 891                 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
 892                         beacon = rcu_dereference(sdata->u.ibss.presp);
 893                 else if (ieee80211_vif_is_mesh(&sdata->vif))
 894                         beacon = rcu_dereference(sdata->u.mesh.beacon);
 895
 896                 if (beacon)
 897                         for (i = 0; i < params->n_csa_offsets; i++)
 898                                 data[params->csa_offsets[i]] =
 899                                         beacon->cntdwn_current_counter;
 900
 901                 rcu_read_unlock();
 902         }
 903
 904         IEEE80211_SKB_CB(skb)->flags = flags;
 905
 906         skb->dev = sdata->dev;
 907
 908         if (!params->dont_wait_for_ack) {
 909                 /* make a copy to preserve the frame contents
 910                  * in case of encryption.
 911                  */
 912                 ret = ieee80211_attach_ack_skb(local, skb, cookie, GFP_KERNEL);
 913                 if (ret) {
 914                         kfree_skb(skb);
 915                         goto out_unlock;
 916                 }
 917         } else {
 918                 /* Assign a dummy non-zero cookie, it's not sent to
 919                  * userspace in this case but we rely on its value
 920                  * internally in the need_offchan case to distinguish
 921                  * mgmt-tx from remain-on-channel.
 922                  */
 923                 *cookie = 0xffffffff;
 924         }
 925
 926         if (!need_offchan) {
 927                 ieee80211_tx_skb(sdata, skb);
 928                 ret = 0;
 929                 goto out_unlock;
 930         }
 931
 932         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_TX_OFFCHAN |
 933                                         IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
 934         if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
 935                 IEEE80211_SKB_CB(skb)->hw_queue =
 936                         local->hw.offchannel_tx_hw_queue;
 937
 938         /* This will handle all kinds of coalescing and immediate TX */
 939         ret = ieee80211_start_roc_work(local, sdata, params->chan,
 940                                        params->wait, cookie, skb,
 941                                        IEEE80211_ROC_TYPE_MGMT_TX);
 942         if (ret)
 943                 ieee80211_free_txskb(&local->hw, skb);
 944  out_unlock:
 945         mutex_unlock(&local->mtx);
 946         return ret;
 947 }
 948
 949 int ieee80211_mgmt_tx_cancel_wait(struct wiphy *wiphy,
 950                                   struct wireless_dev *wdev, u64 cookie)
 951 {
 952         struct ieee80211_local *local = wiphy_priv(wiphy);
 953
 954         return ieee80211_cancel_roc(local, cookie, true);
 955 }
 956
 957 void ieee80211_roc_setup(struct ieee80211_local *local)
 958 {
 959         INIT_WORK(&local->hw_roc_start, ieee80211_hw_roc_start);
 960         INIT_WORK(&local->hw_roc_done, ieee80211_hw_roc_done);
 961         INIT_DELAYED_WORK(&local->roc_work, ieee80211_roc_work);
 962         INIT_LIST_HEAD(&local->roc_list);
 963 }
 964
 965 void ieee80211_roc_purge(struct ieee80211_local *local,
 966                          struct ieee80211_sub_if_data *sdata)
 967 {
 968         struct ieee80211_roc_work *roc, *tmp;
 969         bool work_to_do = false;
 970
 971         mutex_lock(&local->mtx);
 972         list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
 973                 if (sdata && roc->sdata != sdata)
 974                         continue;
 975
 976                 if (roc->started) {
 977                         if (local->ops->remain_on_channel) {
 978                                 /* can race, so ignore return value */
 979                                 drv_cancel_remain_on_channel(local, sdata);
 980                                 ieee80211_roc_notify_destroy(roc);
 981                         } else {
 982                                 roc->abort = true;
 983                                 work_to_do = true;
 984                         }
 985                 } else {
 986                         ieee80211_roc_notify_destroy(roc);
 987                 }
 988         }
 989         if (work_to_do)
 990                 __ieee80211_roc_work(local);
 991         mutex_unlock(&local->mtx);
 992 }