net/mac80211/mesh_ps.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2012-2013, Marco Porsch <marco.porsch@s2005.tu-chemnitz.de>
   4  * Copyright 2012-2013, cozybit Inc.
   5  */
   6
   7 #include "mesh.h"
   8 #include "wme.h"
   9
  10
  11 /* mesh PS management */
  12
  13 /**
  14  * mps_qos_null_get - create pre-addressed QoS Null frame for mesh powersave
  15  */
  16 static struct sk_buff *mps_qos_null_get(struct sta_info *sta)
  17 {
  18         struct ieee80211_sub_if_data *sdata = sta->sdata;
  19         struct ieee80211_local *local = sdata->local;
  20         struct ieee80211_hdr *nullfunc; /* use 4addr header */
  21         struct sk_buff *skb;
  22         int size = sizeof(*nullfunc);
  23         __le16 fc;
  24
  25         skb = dev_alloc_skb(local->hw.extra_tx_headroom + size + 2);
  26         if (!skb)
  27                 return NULL;
  28         skb_reserve(skb, local->hw.extra_tx_headroom);
  29
  30         nullfunc = skb_put(skb, size);
  31         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_QOS_NULLFUNC);
  32         ieee80211_fill_mesh_addresses(nullfunc, &fc, sta->sta.addr,
  33                                       sdata->vif.addr);
  34         nullfunc->frame_control = fc;
  35         nullfunc->duration_id = 0;
  36         nullfunc->seq_ctrl = 0;
  37         /* no address resolution for this frame -> set addr 1 immediately */
  38         memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
  39         skb_put_zero(skb, 2); /* append QoS control field */
  40         ieee80211_mps_set_frame_flags(sdata, sta, nullfunc);
  41
  42         return skb;
  43 }
  44
  45 /**
  46  * mps_qos_null_tx - send a QoS Null to indicate link-specific power mode
  47  */
  48 static void mps_qos_null_tx(struct sta_info *sta)
  49 {
  50         struct sk_buff *skb;
  51
  52         skb = mps_qos_null_get(sta);
  53         if (!skb)
  54                 return;
  55
  56         mps_dbg(sta->sdata, "announcing peer-specific power mode to %pM\n",
  57                 sta->sta.addr);
  58
  59         /* don't unintentionally start a MPSP */
  60         if (!test_sta_flag(sta, WLAN_STA_PS_STA)) {
  61                 u8 *qc = ieee80211_get_qos_ctl((void *) skb->data);
  62
  63                 qc[0] |= IEEE80211_QOS_CTL_EOSP;
  64         }
  65
  66         ieee80211_tx_skb(sta->sdata, skb);
  67 }
  68
  69 /**
  70  * ieee80211_mps_local_status_update - track status of local link-specific PMs
  71  *
  72  * @sdata: local mesh subif
  73  *
  74  * sets the non-peer power mode and triggers the driver PS (re-)configuration
  75  * Return BSS_CHANGED_BEACON if a beacon update is necessary.
  76  */
  77 u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata)
  78 {
  79         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  80         struct sta_info *sta;
  81         bool peering = false;
  82         int light_sleep_cnt = 0;
  83         int deep_sleep_cnt = 0;
  84         u32 changed = 0;
  85         enum nl80211_mesh_power_mode nonpeer_pm;
  86
  87         rcu_read_lock();
  88         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
  89                 if (sdata != sta->sdata)
  90                         continue;
  91
  92                 switch (sta->mesh->plink_state) {
  93                 case NL80211_PLINK_OPN_SNT:
  94                 case NL80211_PLINK_OPN_RCVD:
  95                 case NL80211_PLINK_CNF_RCVD:
  96                         peering = true;
  97                         break;
  98                 case NL80211_PLINK_ESTAB:
  99                         if (sta->mesh->local_pm == NL80211_MESH_POWER_LIGHT_SLEEP)
 100                                 light_sleep_cnt++;
 101                         else if (sta->mesh->local_pm == NL80211_MESH_POWER_DEEP_SLEEP)
 102                                 deep_sleep_cnt++;
 103                         break;
 104                 default:
 105                         break;
 106                 }
 107         }
 108         rcu_read_unlock();
 109
 110         /*
 111          * Set non-peer mode to active during peering/scanning/authentication
 112          * (see IEEE802.11-2012 13.14.8.3). The non-peer mesh power mode is
 113          * deep sleep if the local STA is in light or deep sleep towards at
 114          * least one mesh peer (see 13.14.3.1). Otherwise, set it to the
 115          * user-configured default value.
 116          */
 117         if (peering) {
 118                 mps_dbg(sdata, "setting non-peer PM to active for peering\n");
 119                 nonpeer_pm = NL80211_MESH_POWER_ACTIVE;
 120         } else if (light_sleep_cnt || deep_sleep_cnt) {
 121                 mps_dbg(sdata, "setting non-peer PM to deep sleep\n");
 122                 nonpeer_pm = NL80211_MESH_POWER_DEEP_SLEEP;
 123         } else {
 124                 mps_dbg(sdata, "setting non-peer PM to user value\n");
 125                 nonpeer_pm = ifmsh->mshcfg.power_mode;
 126         }
 127
 128         /* need update if sleep counts move between 0 and non-zero */
 129         if (ifmsh->nonpeer_pm != nonpeer_pm ||
 130             !ifmsh->ps_peers_light_sleep != !light_sleep_cnt ||
 131             !ifmsh->ps_peers_deep_sleep != !deep_sleep_cnt)
 132                 changed = BSS_CHANGED_BEACON;
 133
 134         ifmsh->nonpeer_pm = nonpeer_pm;
 135         ifmsh->ps_peers_light_sleep = light_sleep_cnt;
 136         ifmsh->ps_peers_deep_sleep = deep_sleep_cnt;
 137
 138         return changed;
 139 }
 140
 141 /**
 142  * ieee80211_mps_set_sta_local_pm - set local PM towards a mesh STA
 143  *
 144  * @sta: mesh STA
 145  * @pm: the power mode to set
 146  * Return BSS_CHANGED_BEACON if a beacon update is in order.
 147  */
 148 u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
 149                                    enum nl80211_mesh_power_mode pm)
 150 {
 151         struct ieee80211_sub_if_data *sdata = sta->sdata;
 152
 153         if (sta->mesh->local_pm == pm)
 154                 return 0;
 155
 156         mps_dbg(sdata, "local STA operates in mode %d with %pM\n",
 157                 pm, sta->sta.addr);
 158
 159         sta->mesh->local_pm = pm;
 160
 161         /*
 162          * announce peer-specific power mode transition
 163          * (see IEEE802.11-2012 13.14.3.2 and 13.14.3.3)
 164          */
 165         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 166                 mps_qos_null_tx(sta);
 167
 168         return ieee80211_mps_local_status_update(sdata);
 169 }
 170
 171 /**
 172  * ieee80211_mps_set_frame_flags - set mesh PS flags in FC (and QoS Control)
 173  *
 174  * @sdata: local mesh subif
 175  * @sta: mesh STA
 176  * @hdr: 802.11 frame header
 177  *
 178  * see IEEE802.11-2012 8.2.4.1.7 and 8.2.4.5.11
 179  *
 180  * NOTE: sta must be given when an individually-addressed QoS frame header
 181  * is handled, for group-addressed and management frames it is not used
 182  */
 183 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
 184                                    struct sta_info *sta,
 185                                    struct ieee80211_hdr *hdr)
 186 {
 187         enum nl80211_mesh_power_mode pm;
 188         u8 *qc;
 189
 190         if (WARN_ON(is_unicast_ether_addr(hdr->addr1) &&
 191                     ieee80211_is_data_qos(hdr->frame_control) &&
 192                     !sta))
 193                 return;
 194
 195         if (is_unicast_ether_addr(hdr->addr1) &&
 196             ieee80211_is_data_qos(hdr->frame_control) &&
 197             sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 198                 pm = sta->mesh->local_pm;
 199         else
 200                 pm = sdata->u.mesh.nonpeer_pm;
 201
 202         if (pm == NL80211_MESH_POWER_ACTIVE)
 203                 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_PM);
 204         else
 205                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
 206
 207         if (!ieee80211_is_data_qos(hdr->frame_control))
 208                 return;
 209
 210         qc = ieee80211_get_qos_ctl(hdr);
 211
 212         if ((is_unicast_ether_addr(hdr->addr1) &&
 213              pm == NL80211_MESH_POWER_DEEP_SLEEP) ||
 214             (is_multicast_ether_addr(hdr->addr1) &&
 215              sdata->u.mesh.ps_peers_deep_sleep > 0))
 216                 qc[1] |= (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
 217         else
 218                 qc[1] &= ~(IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
 219 }
 220
 221 /**
 222  * ieee80211_mps_sta_status_update - update buffering status of neighbor STA
 223  *
 224  * @sta: mesh STA
 225  *
 226  * called after change of peering status or non-peer/peer-specific power mode
 227  */
 228 void ieee80211_mps_sta_status_update(struct sta_info *sta)
 229 {
 230         enum nl80211_mesh_power_mode pm;
 231         bool do_buffer;
 232
 233         /* For non-assoc STA, prevent buffering or frame transmission */
 234         if (sta->sta_state < IEEE80211_STA_ASSOC)
 235                 return;
 236
 237         /*
 238          * use peer-specific power mode if peering is established and the
 239          * peer's power mode is known
 240          */
 241         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
 242             sta->mesh->peer_pm != NL80211_MESH_POWER_UNKNOWN)
 243                 pm = sta->mesh->peer_pm;
 244         else
 245                 pm = sta->mesh->nonpeer_pm;
 246
 247         do_buffer = (pm != NL80211_MESH_POWER_ACTIVE);
 248
 249         /* clear the MPSP flags for non-peers or active STA */
 250         if (sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
 251                 clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
 252                 clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 253         } else if (!do_buffer) {
 254                 clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
 255         }
 256
 257         /* Don't let the same PS state be set twice */
 258         if (test_sta_flag(sta, WLAN_STA_PS_STA) == do_buffer)
 259                 return;
 260
 261         if (do_buffer) {
 262                 set_sta_flag(sta, WLAN_STA_PS_STA);
 263                 atomic_inc(&sta->sdata->u.mesh.ps.num_sta_ps);
 264                 mps_dbg(sta->sdata, "start PS buffering frames towards %pM\n",
 265                         sta->sta.addr);
 266         } else {
 267                 ieee80211_sta_ps_deliver_wakeup(sta);
 268         }
 269 }
 270
 271 static void mps_set_sta_peer_pm(struct sta_info *sta,
 272                                 struct ieee80211_hdr *hdr)
 273 {
 274         enum nl80211_mesh_power_mode pm;
 275         u8 *qc = ieee80211_get_qos_ctl(hdr);
 276
 277         /*
 278          * Test Power Management field of frame control (PW) and
 279          * mesh power save level subfield of QoS control field (PSL)
 280          *
 281          * | PM | PSL| Mesh PM |
 282          * +----+----+---------+
 283          * | 0  |Rsrv|  Active |
 284          * | 1  | 0  |  Light  |
 285          * | 1  | 1  |  Deep   |
 286          */
 287         if (ieee80211_has_pm(hdr->frame_control)) {
 288                 if (qc[1] & (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8))
 289                         pm = NL80211_MESH_POWER_DEEP_SLEEP;
 290                 else
 291                         pm = NL80211_MESH_POWER_LIGHT_SLEEP;
 292         } else {
 293                 pm = NL80211_MESH_POWER_ACTIVE;
 294         }
 295
 296         if (sta->mesh->peer_pm == pm)
 297                 return;
 298
 299         mps_dbg(sta->sdata, "STA %pM enters mode %d\n",
 300                 sta->sta.addr, pm);
 301
 302         sta->mesh->peer_pm = pm;
 303
 304         ieee80211_mps_sta_status_update(sta);
 305 }
 306
 307 static void mps_set_sta_nonpeer_pm(struct sta_info *sta,
 308                                    struct ieee80211_hdr *hdr)
 309 {
 310         enum nl80211_mesh_power_mode pm;
 311
 312         if (ieee80211_has_pm(hdr->frame_control))
 313                 pm = NL80211_MESH_POWER_DEEP_SLEEP;
 314         else
 315                 pm = NL80211_MESH_POWER_ACTIVE;
 316
 317         if (sta->mesh->nonpeer_pm == pm)
 318                 return;
 319
 320         mps_dbg(sta->sdata, "STA %pM sets non-peer mode to %d\n",
 321                 sta->sta.addr, pm);
 322
 323         sta->mesh->nonpeer_pm = pm;
 324
 325         ieee80211_mps_sta_status_update(sta);
 326 }
 327
 328 /**
 329  * ieee80211_mps_rx_h_sta_process - frame receive handler for mesh powersave
 330  *
 331  * @sta: STA info that transmitted the frame
 332  * @hdr: IEEE 802.11 (QoS) Header
 333  */
 334 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
 335                                     struct ieee80211_hdr *hdr)
 336 {
 337         if (is_unicast_ether_addr(hdr->addr1) &&
 338             ieee80211_is_data_qos(hdr->frame_control)) {
 339                 /*
 340                  * individually addressed QoS Data/Null frames contain
 341                  * peer link-specific PS mode towards the local STA
 342                  */
 343                 mps_set_sta_peer_pm(sta, hdr);
 344
 345                 /* check for mesh Peer Service Period trigger frames */
 346                 ieee80211_mpsp_trigger_process(ieee80211_get_qos_ctl(hdr),
 347                                                sta, false, false);
 348         } else {
 349                 /*
 350                  * can only determine non-peer PS mode
 351                  * (see IEEE802.11-2012 8.2.4.1.7)
 352                  */
 353                 mps_set_sta_nonpeer_pm(sta, hdr);
 354         }
 355 }
 356
 357
 358 /* mesh PS frame release */
 359
 360 static void mpsp_trigger_send(struct sta_info *sta, bool rspi, bool eosp)
 361 {
 362         struct ieee80211_sub_if_data *sdata = sta->sdata;
 363         struct sk_buff *skb;
 364         struct ieee80211_hdr *nullfunc;
 365         struct ieee80211_tx_info *info;
 366         u8 *qc;
 367
 368         skb = mps_qos_null_get(sta);
 369         if (!skb)
 370                 return;
 371
 372         nullfunc = (struct ieee80211_hdr *) skb->data;
 373         if (!eosp)
 374                 nullfunc->frame_control |=
 375                                 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 376         /*
 377          * | RSPI | EOSP |  MPSP triggering   |
 378          * +------+------+--------------------+
 379          * |  0   |  0   | local STA is owner |
 380          * |  0   |  1   | no MPSP (MPSP end) |
 381          * |  1   |  0   | both STA are owner |
 382          * |  1   |  1   | peer STA is owner  | see IEEE802.11-2012 13.14.9.2
 383          */
 384         qc = ieee80211_get_qos_ctl(nullfunc);
 385         if (rspi)
 386                 qc[1] |= (IEEE80211_QOS_CTL_RSPI >> 8);
 387         if (eosp)
 388                 qc[0] |= IEEE80211_QOS_CTL_EOSP;
 389
 390         info = IEEE80211_SKB_CB(skb);
 391
 392         info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER |
 393                        IEEE80211_TX_CTL_REQ_TX_STATUS;
 394
 395         mps_dbg(sdata, "sending MPSP trigger%s%s to %pM\n",
 396                 rspi ? " RSPI" : "", eosp ? " EOSP" : "", sta->sta.addr);
 397
 398         ieee80211_tx_skb(sdata, skb);
 399 }
 400
 401 /**
 402  * mpsp_qos_null_append - append QoS Null frame to MPSP skb queue if needed
 403  *
 404  * To properly end a mesh MPSP the last transmitted frame has to set the EOSP
 405  * flag in the QoS Control field. In case the current tailing frame is not a
 406  * QoS Data frame, append a QoS Null to carry the flag.
 407  */
 408 static void mpsp_qos_null_append(struct sta_info *sta,
 409                                  struct sk_buff_head *frames)
 410 {
 411         struct ieee80211_sub_if_data *sdata = sta->sdata;
 412         struct sk_buff *new_skb, *skb = skb_peek_tail(frames);
 413         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 414         struct ieee80211_tx_info *info;
 415
 416         if (ieee80211_is_data_qos(hdr->frame_control))
 417                 return;
 418
 419         new_skb = mps_qos_null_get(sta);
 420         if (!new_skb)
 421                 return;
 422
 423         mps_dbg(sdata, "appending QoS Null in MPSP towards %pM\n",
 424                 sta->sta.addr);
 425         /*
 426          * This frame has to be transmitted last. Assign lowest priority to
 427          * make sure it cannot pass other frames when releasing multiple ACs.
 428          */
 429         new_skb->priority = 1;
 430         skb_set_queue_mapping(new_skb, IEEE80211_AC_BK);
 431         ieee80211_set_qos_hdr(sdata, new_skb);
 432
 433         info = IEEE80211_SKB_CB(new_skb);
 434         info->control.vif = &sdata->vif;
 435         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
 436
 437         __skb_queue_tail(frames, new_skb);
 438 }
 439
 440 /**
 441  * mps_frame_deliver - transmit frames during mesh powersave
 442  *
 443  * @sta: STA info to transmit to
 444  * @n_frames: number of frames to transmit. -1 for all
 445  */
 446 static void mps_frame_deliver(struct sta_info *sta, int n_frames)
 447 {
 448         struct ieee80211_local *local = sta->sdata->local;
 449         int ac;
 450         struct sk_buff_head frames;
 451         struct sk_buff *skb;
 452         bool more_data = false;
 453
 454         skb_queue_head_init(&frames);
 455
 456         /* collect frame(s) from buffers */
 457         for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
 458                 while (n_frames != 0) {
 459                         skb = skb_dequeue(&sta->tx_filtered[ac]);
 460                         if (!skb) {
 461                                 skb = skb_dequeue(
 462                                         &sta->ps_tx_buf[ac]);
 463                                 if (skb)
 464                                         local->total_ps_buffered--;
 465                         }
 466                         if (!skb)
 467                                 break;
 468                         n_frames--;
 469                         __skb_queue_tail(&frames, skb);
 470                 }
 471
 472                 if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
 473                     !skb_queue_empty(&sta->ps_tx_buf[ac]))
 474                         more_data = true;
 475         }
 476
 477         /* nothing to send? -> EOSP */
 478         if (skb_queue_empty(&frames)) {
 479                 mpsp_trigger_send(sta, false, true);
 480                 return;
 481         }
 482
 483         /* in a MPSP make sure the last skb is a QoS Data frame */
 484         if (test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 485                 mpsp_qos_null_append(sta, &frames);
 486
 487         mps_dbg(sta->sdata, "sending %d frames to PS STA %pM\n",
 488                 skb_queue_len(&frames), sta->sta.addr);
 489
 490         /* prepare collected frames for transmission */
 491         skb_queue_walk(&frames, skb) {
 492                 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 493                 struct ieee80211_hdr *hdr = (void *) skb->data;
 494
 495                 /*
 496                  * Tell TX path to send this frame even though the
 497                  * STA may still remain is PS mode after this frame
 498                  * exchange.
 499                  */
 500                 info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
 501
 502                 if (more_data || !skb_queue_is_last(&frames, skb))
 503                         hdr->frame_control |=
 504                                 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 505                 else
 506                         hdr->frame_control &=
 507                                 cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 508
 509                 if (skb_queue_is_last(&frames, skb) &&
 510                     ieee80211_is_data_qos(hdr->frame_control)) {
 511                         u8 *qoshdr = ieee80211_get_qos_ctl(hdr);
 512
 513                         /* MPSP trigger frame ends service period */
 514                         *qoshdr |= IEEE80211_QOS_CTL_EOSP;
 515                         info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 516                 }
 517         }
 518
 519         ieee80211_add_pending_skbs(local, &frames);
 520         sta_info_recalc_tim(sta);
 521 }
 522
 523 /**
 524  * ieee80211_mpsp_trigger_process - track status of mesh Peer Service Periods
 525  *
 526  * @qc: QoS Control field
 527  * @sta: peer to start a MPSP with
 528  * @tx: frame was transmitted by the local STA
 529  * @acked: frame has been transmitted successfully
 530  *
 531  * NOTE: active mode STA may only serve as MPSP owner
 532  */
 533 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
 534                                     bool tx, bool acked)
 535 {
 536         u8 rspi = qc[1] & (IEEE80211_QOS_CTL_RSPI >> 8);
 537         u8 eosp = qc[0] & IEEE80211_QOS_CTL_EOSP;
 538
 539         if (tx) {
 540                 if (rspi && acked)
 541                         set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 542
 543                 if (eosp)
 544                         clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
 545                 else if (acked &&
 546                          test_sta_flag(sta, WLAN_STA_PS_STA) &&
 547                          !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 548                         mps_frame_deliver(sta, -1);
 549         } else {
 550                 if (eosp)
 551                         clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 552                 else if (sta->mesh->local_pm != NL80211_MESH_POWER_ACTIVE)
 553                         set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 554
 555                 if (rspi && !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 556                         mps_frame_deliver(sta, -1);
 557         }
 558 }
 559
 560 /**
 561  * ieee80211_mps_frame_release - release frames buffered due to mesh power save
 562  *
 563  * @sta: mesh STA
 564  * @elems: IEs of beacon or probe response
 565  *
 566  * For peers if we have individually-addressed frames buffered or the peer
 567  * indicates buffered frames, send a corresponding MPSP trigger frame. Since
 568  * we do not evaluate the awake window duration, QoS Nulls are used as MPSP
 569  * trigger frames. If the neighbour STA is not a peer, only send single frames.
 570  */
 571 void ieee80211_mps_frame_release(struct sta_info *sta,
 572                                  struct ieee802_11_elems *elems)
 573 {
 574         int ac, buffer_local = 0;
 575         bool has_buffered = false;
 576
 577         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 578                 has_buffered = ieee80211_check_tim(elems->tim, elems->tim_len,
 579                                                    sta->mesh->aid);
 580
 581         if (has_buffered)
 582                 mps_dbg(sta->sdata, "%pM indicates buffered frames\n",
 583                         sta->sta.addr);
 584
 585         /* only transmit to PS STA with announced, non-zero awake window */
 586         if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
 587             (!elems->awake_window || !le16_to_cpu(*elems->awake_window)))
 588                 return;
 589
 590         if (!test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 591                 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
 592                         buffer_local += skb_queue_len(&sta->ps_tx_buf[ac]) +
 593                                         skb_queue_len(&sta->tx_filtered[ac]);
 594
 595         if (!has_buffered && !buffer_local)
 596                 return;
 597
 598         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 599                 mpsp_trigger_send(sta, has_buffered, !buffer_local);
 600         else
 601                 mps_frame_deliver(sta, 1);
 602 }