linux/net/mac80211/mesh_ps.c
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   1/*
   2 * Copyright 2012-2013, Marco Porsch <marco.porsch@s2005.tu-chemnitz.de>
   3 * Copyright 2012-2013, cozybit Inc.
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License version 2 as
   7 * published by the Free Software Foundation.
   8 */
   9
  10#include "mesh.h"
  11#include "wme.h"
  12
  13
  14/* mesh PS management */
  15
  16/**
  17 * mps_qos_null_get - create pre-addressed QoS Null frame for mesh powersave
  18 */
  19static struct sk_buff *mps_qos_null_get(struct sta_info *sta)
  20{
  21        struct ieee80211_sub_if_data *sdata = sta->sdata;
  22        struct ieee80211_local *local = sdata->local;
  23        struct ieee80211_hdr *nullfunc; /* use 4addr header */
  24        struct sk_buff *skb;
  25        int size = sizeof(*nullfunc);
  26        __le16 fc;
  27
  28        skb = dev_alloc_skb(local->hw.extra_tx_headroom + size + 2);
  29        if (!skb)
  30                return NULL;
  31        skb_reserve(skb, local->hw.extra_tx_headroom);
  32
  33        nullfunc = skb_put(skb, size);
  34        fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_QOS_NULLFUNC);
  35        ieee80211_fill_mesh_addresses(nullfunc, &fc, sta->sta.addr,
  36                                      sdata->vif.addr);
  37        nullfunc->frame_control = fc;
  38        nullfunc->duration_id = 0;
  39        nullfunc->seq_ctrl = 0;
  40        /* no address resolution for this frame -> set addr 1 immediately */
  41        memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
  42        skb_put_zero(skb, 2); /* append QoS control field */
  43        ieee80211_mps_set_frame_flags(sdata, sta, nullfunc);
  44
  45        return skb;
  46}
  47
  48/**
  49 * mps_qos_null_tx - send a QoS Null to indicate link-specific power mode
  50 */
  51static void mps_qos_null_tx(struct sta_info *sta)
  52{
  53        struct sk_buff *skb;
  54
  55        skb = mps_qos_null_get(sta);
  56        if (!skb)
  57                return;
  58
  59        mps_dbg(sta->sdata, "announcing peer-specific power mode to %pM\n",
  60                sta->sta.addr);
  61
  62        /* don't unintentionally start a MPSP */
  63        if (!test_sta_flag(sta, WLAN_STA_PS_STA)) {
  64                u8 *qc = ieee80211_get_qos_ctl((void *) skb->data);
  65
  66                qc[0] |= IEEE80211_QOS_CTL_EOSP;
  67        }
  68
  69        ieee80211_tx_skb(sta->sdata, skb);
  70}
  71
  72/**
  73 * ieee80211_mps_local_status_update - track status of local link-specific PMs
  74 *
  75 * @sdata: local mesh subif
  76 *
  77 * sets the non-peer power mode and triggers the driver PS (re-)configuration
  78 * Return BSS_CHANGED_BEACON if a beacon update is necessary.
  79 */
  80u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata)
  81{
  82        struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  83        struct sta_info *sta;
  84        bool peering = false;
  85        int light_sleep_cnt = 0;
  86        int deep_sleep_cnt = 0;
  87        u32 changed = 0;
  88        enum nl80211_mesh_power_mode nonpeer_pm;
  89
  90        rcu_read_lock();
  91        list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
  92                if (sdata != sta->sdata)
  93                        continue;
  94
  95                switch (sta->mesh->plink_state) {
  96                case NL80211_PLINK_OPN_SNT:
  97                case NL80211_PLINK_OPN_RCVD:
  98                case NL80211_PLINK_CNF_RCVD:
  99                        peering = true;
 100                        break;
 101                case NL80211_PLINK_ESTAB:
 102                        if (sta->mesh->local_pm == NL80211_MESH_POWER_LIGHT_SLEEP)
 103                                light_sleep_cnt++;
 104                        else if (sta->mesh->local_pm == NL80211_MESH_POWER_DEEP_SLEEP)
 105                                deep_sleep_cnt++;
 106                        break;
 107                default:
 108                        break;
 109                }
 110        }
 111        rcu_read_unlock();
 112
 113        /*
 114         * Set non-peer mode to active during peering/scanning/authentication
 115         * (see IEEE802.11-2012 13.14.8.3). The non-peer mesh power mode is
 116         * deep sleep if the local STA is in light or deep sleep towards at
 117         * least one mesh peer (see 13.14.3.1). Otherwise, set it to the
 118         * user-configured default value.
 119         */
 120        if (peering) {
 121                mps_dbg(sdata, "setting non-peer PM to active for peering\n");
 122                nonpeer_pm = NL80211_MESH_POWER_ACTIVE;
 123        } else if (light_sleep_cnt || deep_sleep_cnt) {
 124                mps_dbg(sdata, "setting non-peer PM to deep sleep\n");
 125                nonpeer_pm = NL80211_MESH_POWER_DEEP_SLEEP;
 126        } else {
 127                mps_dbg(sdata, "setting non-peer PM to user value\n");
 128                nonpeer_pm = ifmsh->mshcfg.power_mode;
 129        }
 130
 131        /* need update if sleep counts move between 0 and non-zero */
 132        if (ifmsh->nonpeer_pm != nonpeer_pm ||
 133            !ifmsh->ps_peers_light_sleep != !light_sleep_cnt ||
 134            !ifmsh->ps_peers_deep_sleep != !deep_sleep_cnt)
 135                changed = BSS_CHANGED_BEACON;
 136
 137        ifmsh->nonpeer_pm = nonpeer_pm;
 138        ifmsh->ps_peers_light_sleep = light_sleep_cnt;
 139        ifmsh->ps_peers_deep_sleep = deep_sleep_cnt;
 140
 141        return changed;
 142}
 143
 144/**
 145 * ieee80211_mps_set_sta_local_pm - set local PM towards a mesh STA
 146 *
 147 * @sta: mesh STA
 148 * @pm: the power mode to set
 149 * Return BSS_CHANGED_BEACON if a beacon update is in order.
 150 */
 151u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
 152                                   enum nl80211_mesh_power_mode pm)
 153{
 154        struct ieee80211_sub_if_data *sdata = sta->sdata;
 155
 156        if (sta->mesh->local_pm == pm)
 157                return 0;
 158
 159        mps_dbg(sdata, "local STA operates in mode %d with %pM\n",
 160                pm, sta->sta.addr);
 161
 162        sta->mesh->local_pm = pm;
 163
 164        /*
 165         * announce peer-specific power mode transition
 166         * (see IEEE802.11-2012 13.14.3.2 and 13.14.3.3)
 167         */
 168        if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 169                mps_qos_null_tx(sta);
 170
 171        return ieee80211_mps_local_status_update(sdata);
 172}
 173
 174/**
 175 * ieee80211_mps_set_frame_flags - set mesh PS flags in FC (and QoS Control)
 176 *
 177 * @sdata: local mesh subif
 178 * @sta: mesh STA
 179 * @hdr: 802.11 frame header
 180 *
 181 * see IEEE802.11-2012 8.2.4.1.7 and 8.2.4.5.11
 182 *
 183 * NOTE: sta must be given when an individually-addressed QoS frame header
 184 * is handled, for group-addressed and management frames it is not used
 185 */
 186void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
 187                                   struct sta_info *sta,
 188                                   struct ieee80211_hdr *hdr)
 189{
 190        enum nl80211_mesh_power_mode pm;
 191        u8 *qc;
 192
 193        if (WARN_ON(is_unicast_ether_addr(hdr->addr1) &&
 194                    ieee80211_is_data_qos(hdr->frame_control) &&
 195                    !sta))
 196                return;
 197
 198        if (is_unicast_ether_addr(hdr->addr1) &&
 199            ieee80211_is_data_qos(hdr->frame_control) &&
 200            sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 201                pm = sta->mesh->local_pm;
 202        else
 203                pm = sdata->u.mesh.nonpeer_pm;
 204
 205        if (pm == NL80211_MESH_POWER_ACTIVE)
 206                hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_PM);
 207        else
 208                hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
 209
 210        if (!ieee80211_is_data_qos(hdr->frame_control))
 211                return;
 212
 213        qc = ieee80211_get_qos_ctl(hdr);
 214
 215        if ((is_unicast_ether_addr(hdr->addr1) &&
 216             pm == NL80211_MESH_POWER_DEEP_SLEEP) ||
 217            (is_multicast_ether_addr(hdr->addr1) &&
 218             sdata->u.mesh.ps_peers_deep_sleep > 0))
 219                qc[1] |= (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
 220        else
 221                qc[1] &= ~(IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
 222}
 223
 224/**
 225 * ieee80211_mps_sta_status_update - update buffering status of neighbor STA
 226 *
 227 * @sta: mesh STA
 228 *
 229 * called after change of peering status or non-peer/peer-specific power mode
 230 */
 231void ieee80211_mps_sta_status_update(struct sta_info *sta)
 232{
 233        enum nl80211_mesh_power_mode pm;
 234        bool do_buffer;
 235
 236        /* For non-assoc STA, prevent buffering or frame transmission */
 237        if (sta->sta_state < IEEE80211_STA_ASSOC)
 238                return;
 239
 240        /*
 241         * use peer-specific power mode if peering is established and the
 242         * peer's power mode is known
 243         */
 244        if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
 245            sta->mesh->peer_pm != NL80211_MESH_POWER_UNKNOWN)
 246                pm = sta->mesh->peer_pm;
 247        else
 248                pm = sta->mesh->nonpeer_pm;
 249
 250        do_buffer = (pm != NL80211_MESH_POWER_ACTIVE);
 251
 252        /* clear the MPSP flags for non-peers or active STA */
 253        if (sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
 254                clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
 255                clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 256        } else if (!do_buffer) {
 257                clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
 258        }
 259
 260        /* Don't let the same PS state be set twice */
 261        if (test_sta_flag(sta, WLAN_STA_PS_STA) == do_buffer)
 262                return;
 263
 264        if (do_buffer) {
 265                set_sta_flag(sta, WLAN_STA_PS_STA);
 266                atomic_inc(&sta->sdata->u.mesh.ps.num_sta_ps);
 267                mps_dbg(sta->sdata, "start PS buffering frames towards %pM\n",
 268                        sta->sta.addr);
 269        } else {
 270                ieee80211_sta_ps_deliver_wakeup(sta);
 271        }
 272}
 273
 274static void mps_set_sta_peer_pm(struct sta_info *sta,
 275                                struct ieee80211_hdr *hdr)
 276{
 277        enum nl80211_mesh_power_mode pm;
 278        u8 *qc = ieee80211_get_qos_ctl(hdr);
 279
 280        /*
 281         * Test Power Management field of frame control (PW) and
 282         * mesh power save level subfield of QoS control field (PSL)
 283         *
 284         * | PM | PSL| Mesh PM |
 285         * +----+----+---------+
 286         * | 0  |Rsrv|  Active |
 287         * | 1  | 0  |  Light  |
 288         * | 1  | 1  |  Deep   |
 289         */
 290        if (ieee80211_has_pm(hdr->frame_control)) {
 291                if (qc[1] & (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8))
 292                        pm = NL80211_MESH_POWER_DEEP_SLEEP;
 293                else
 294                        pm = NL80211_MESH_POWER_LIGHT_SLEEP;
 295        } else {
 296                pm = NL80211_MESH_POWER_ACTIVE;
 297        }
 298
 299        if (sta->mesh->peer_pm == pm)
 300                return;
 301
 302        mps_dbg(sta->sdata, "STA %pM enters mode %d\n",
 303                sta->sta.addr, pm);
 304
 305        sta->mesh->peer_pm = pm;
 306
 307        ieee80211_mps_sta_status_update(sta);
 308}
 309
 310static void mps_set_sta_nonpeer_pm(struct sta_info *sta,
 311                                   struct ieee80211_hdr *hdr)
 312{
 313        enum nl80211_mesh_power_mode pm;
 314
 315        if (ieee80211_has_pm(hdr->frame_control))
 316                pm = NL80211_MESH_POWER_DEEP_SLEEP;
 317        else
 318                pm = NL80211_MESH_POWER_ACTIVE;
 319
 320        if (sta->mesh->nonpeer_pm == pm)
 321                return;
 322
 323        mps_dbg(sta->sdata, "STA %pM sets non-peer mode to %d\n",
 324                sta->sta.addr, pm);
 325
 326        sta->mesh->nonpeer_pm = pm;
 327
 328        ieee80211_mps_sta_status_update(sta);
 329}
 330
 331/**
 332 * ieee80211_mps_rx_h_sta_process - frame receive handler for mesh powersave
 333 *
 334 * @sta: STA info that transmitted the frame
 335 * @hdr: IEEE 802.11 (QoS) Header
 336 */
 337void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
 338                                    struct ieee80211_hdr *hdr)
 339{
 340        if (is_unicast_ether_addr(hdr->addr1) &&
 341            ieee80211_is_data_qos(hdr->frame_control)) {
 342                /*
 343                 * individually addressed QoS Data/Null frames contain
 344                 * peer link-specific PS mode towards the local STA
 345                 */
 346                mps_set_sta_peer_pm(sta, hdr);
 347
 348                /* check for mesh Peer Service Period trigger frames */
 349                ieee80211_mpsp_trigger_process(ieee80211_get_qos_ctl(hdr),
 350                                               sta, false, false);
 351        } else {
 352                /*
 353                 * can only determine non-peer PS mode
 354                 * (see IEEE802.11-2012 8.2.4.1.7)
 355                 */
 356                mps_set_sta_nonpeer_pm(sta, hdr);
 357        }
 358}
 359
 360
 361/* mesh PS frame release */
 362
 363static void mpsp_trigger_send(struct sta_info *sta, bool rspi, bool eosp)
 364{
 365        struct ieee80211_sub_if_data *sdata = sta->sdata;
 366        struct sk_buff *skb;
 367        struct ieee80211_hdr *nullfunc;
 368        struct ieee80211_tx_info *info;
 369        u8 *qc;
 370
 371        skb = mps_qos_null_get(sta);
 372        if (!skb)
 373                return;
 374
 375        nullfunc = (struct ieee80211_hdr *) skb->data;
 376        if (!eosp)
 377                nullfunc->frame_control |=
 378                                cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 379        /*
 380         * | RSPI | EOSP |  MPSP triggering   |
 381         * +------+------+--------------------+
 382         * |  0   |  0   | local STA is owner |
 383         * |  0   |  1   | no MPSP (MPSP end) |
 384         * |  1   |  0   | both STA are owner |
 385         * |  1   |  1   | peer STA is owner  | see IEEE802.11-2012 13.14.9.2
 386         */
 387        qc = ieee80211_get_qos_ctl(nullfunc);
 388        if (rspi)
 389                qc[1] |= (IEEE80211_QOS_CTL_RSPI >> 8);
 390        if (eosp)
 391                qc[0] |= IEEE80211_QOS_CTL_EOSP;
 392
 393        info = IEEE80211_SKB_CB(skb);
 394
 395        info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER |
 396                       IEEE80211_TX_CTL_REQ_TX_STATUS;
 397
 398        mps_dbg(sdata, "sending MPSP trigger%s%s to %pM\n",
 399                rspi ? " RSPI" : "", eosp ? " EOSP" : "", sta->sta.addr);
 400
 401        ieee80211_tx_skb(sdata, skb);
 402}
 403
 404/**
 405 * mpsp_qos_null_append - append QoS Null frame to MPSP skb queue if needed
 406 *
 407 * To properly end a mesh MPSP the last transmitted frame has to set the EOSP
 408 * flag in the QoS Control field. In case the current tailing frame is not a
 409 * QoS Data frame, append a QoS Null to carry the flag.
 410 */
 411static void mpsp_qos_null_append(struct sta_info *sta,
 412                                 struct sk_buff_head *frames)
 413{
 414        struct ieee80211_sub_if_data *sdata = sta->sdata;
 415        struct sk_buff *new_skb, *skb = skb_peek_tail(frames);
 416        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 417        struct ieee80211_tx_info *info;
 418
 419        if (ieee80211_is_data_qos(hdr->frame_control))
 420                return;
 421
 422        new_skb = mps_qos_null_get(sta);
 423        if (!new_skb)
 424                return;
 425
 426        mps_dbg(sdata, "appending QoS Null in MPSP towards %pM\n",
 427                sta->sta.addr);
 428        /*
 429         * This frame has to be transmitted last. Assign lowest priority to
 430         * make sure it cannot pass other frames when releasing multiple ACs.
 431         */
 432        new_skb->priority = 1;
 433        skb_set_queue_mapping(new_skb, IEEE80211_AC_BK);
 434        ieee80211_set_qos_hdr(sdata, new_skb);
 435
 436        info = IEEE80211_SKB_CB(new_skb);
 437        info->control.vif = &sdata->vif;
 438        info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
 439
 440        __skb_queue_tail(frames, new_skb);
 441}
 442
 443/**
 444 * mps_frame_deliver - transmit frames during mesh powersave
 445 *
 446 * @sta: STA info to transmit to
 447 * @n_frames: number of frames to transmit. -1 for all
 448 */
 449static void mps_frame_deliver(struct sta_info *sta, int n_frames)
 450{
 451        struct ieee80211_local *local = sta->sdata->local;
 452        int ac;
 453        struct sk_buff_head frames;
 454        struct sk_buff *skb;
 455        bool more_data = false;
 456
 457        skb_queue_head_init(&frames);
 458
 459        /* collect frame(s) from buffers */
 460        for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
 461                while (n_frames != 0) {
 462                        skb = skb_dequeue(&sta->tx_filtered[ac]);
 463                        if (!skb) {
 464                                skb = skb_dequeue(
 465                                        &sta->ps_tx_buf[ac]);
 466                                if (skb)
 467                                        local->total_ps_buffered--;
 468                        }
 469                        if (!skb)
 470                                break;
 471                        n_frames--;
 472                        __skb_queue_tail(&frames, skb);
 473                }
 474
 475                if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
 476                    !skb_queue_empty(&sta->ps_tx_buf[ac]))
 477                        more_data = true;
 478        }
 479
 480        /* nothing to send? -> EOSP */
 481        if (skb_queue_empty(&frames)) {
 482                mpsp_trigger_send(sta, false, true);
 483                return;
 484        }
 485
 486        /* in a MPSP make sure the last skb is a QoS Data frame */
 487        if (test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 488                mpsp_qos_null_append(sta, &frames);
 489
 490        mps_dbg(sta->sdata, "sending %d frames to PS STA %pM\n",
 491                skb_queue_len(&frames), sta->sta.addr);
 492
 493        /* prepare collected frames for transmission */
 494        skb_queue_walk(&frames, skb) {
 495                struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 496                struct ieee80211_hdr *hdr = (void *) skb->data;
 497
 498                /*
 499                 * Tell TX path to send this frame even though the
 500                 * STA may still remain is PS mode after this frame
 501                 * exchange.
 502                 */
 503                info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
 504
 505                if (more_data || !skb_queue_is_last(&frames, skb))
 506                        hdr->frame_control |=
 507                                cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 508                else
 509                        hdr->frame_control &=
 510                                cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 511
 512                if (skb_queue_is_last(&frames, skb) &&
 513                    ieee80211_is_data_qos(hdr->frame_control)) {
 514                        u8 *qoshdr = ieee80211_get_qos_ctl(hdr);
 515
 516                        /* MPSP trigger frame ends service period */
 517                        *qoshdr |= IEEE80211_QOS_CTL_EOSP;
 518                        info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 519                }
 520        }
 521
 522        ieee80211_add_pending_skbs(local, &frames);
 523        sta_info_recalc_tim(sta);
 524}
 525
 526/**
 527 * ieee80211_mpsp_trigger_process - track status of mesh Peer Service Periods
 528 *
 529 * @qc: QoS Control field
 530 * @sta: peer to start a MPSP with
 531 * @tx: frame was transmitted by the local STA
 532 * @acked: frame has been transmitted successfully
 533 *
 534 * NOTE: active mode STA may only serve as MPSP owner
 535 */
 536void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
 537                                    bool tx, bool acked)
 538{
 539        u8 rspi = qc[1] & (IEEE80211_QOS_CTL_RSPI >> 8);
 540        u8 eosp = qc[0] & IEEE80211_QOS_CTL_EOSP;
 541
 542        if (tx) {
 543                if (rspi && acked)
 544                        set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 545
 546                if (eosp)
 547                        clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
 548                else if (acked &&
 549                         test_sta_flag(sta, WLAN_STA_PS_STA) &&
 550                         !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 551                        mps_frame_deliver(sta, -1);
 552        } else {
 553                if (eosp)
 554                        clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 555                else if (sta->mesh->local_pm != NL80211_MESH_POWER_ACTIVE)
 556                        set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
 557
 558                if (rspi && !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 559                        mps_frame_deliver(sta, -1);
 560        }
 561}
 562
 563/**
 564 * ieee80211_mps_frame_release - release frames buffered due to mesh power save
 565 *
 566 * @sta: mesh STA
 567 * @elems: IEs of beacon or probe response
 568 *
 569 * For peers if we have individually-addressed frames buffered or the peer
 570 * indicates buffered frames, send a corresponding MPSP trigger frame. Since
 571 * we do not evaluate the awake window duration, QoS Nulls are used as MPSP
 572 * trigger frames. If the neighbour STA is not a peer, only send single frames.
 573 */
 574void ieee80211_mps_frame_release(struct sta_info *sta,
 575                                 struct ieee802_11_elems *elems)
 576{
 577        int ac, buffer_local = 0;
 578        bool has_buffered = false;
 579
 580        if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 581                has_buffered = ieee80211_check_tim(elems->tim, elems->tim_len,
 582                                                   sta->mesh->aid);
 583
 584        if (has_buffered)
 585                mps_dbg(sta->sdata, "%pM indicates buffered frames\n",
 586                        sta->sta.addr);
 587
 588        /* only transmit to PS STA with announced, non-zero awake window */
 589        if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
 590            (!elems->awake_window || !le16_to_cpu(*elems->awake_window)))
 591                return;
 592
 593        if (!test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
 594                for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
 595                        buffer_local += skb_queue_len(&sta->ps_tx_buf[ac]) +
 596                                        skb_queue_len(&sta->tx_filtered[ac]);
 597
 598        if (!has_buffered && !buffer_local)
 599                return;
 600
 601        if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 602                mpsp_trigger_send(sta, has_buffered, !buffer_local);
 603        else
 604                mps_frame_deliver(sta, 1);
 605}
 606