xref: /linux/net/mac80211/mesh_ps.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
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  * Copyright (C) 2021 Intel Corporation
6  * Copyright (C) 2023 Intel Corporation
7  */
8 
9 #include "mesh.h"
10 #include "wme.h"
11 
12 
13 /* mesh PS management */
14 
15 /**
16  * mps_qos_null_get - create pre-addressed QoS Null frame for mesh powersave
17  * @sta: the station to get the frame for
18  *
19  * Returns: A newly allocated SKB
20  */
21 static struct sk_buff *mps_qos_null_get(struct sta_info *sta)
22 {
23 	struct ieee80211_sub_if_data *sdata = sta->sdata;
24 	struct ieee80211_local *local = sdata->local;
25 	struct ieee80211_hdr *nullfunc; /* use 4addr header */
26 	struct sk_buff *skb;
27 	int size = sizeof(*nullfunc);
28 	__le16 fc;
29 
30 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + size + 2);
31 	if (!skb)
32 		return NULL;
33 	skb_reserve(skb, local->hw.extra_tx_headroom);
34 
35 	nullfunc = skb_put(skb, size);
36 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_QOS_NULLFUNC);
37 	ieee80211_fill_mesh_addresses(nullfunc, &fc, sta->sta.addr,
38 				      sdata->vif.addr);
39 	nullfunc->frame_control = fc;
40 	nullfunc->duration_id = 0;
41 	nullfunc->seq_ctrl = 0;
42 	/* no address resolution for this frame -> set addr 1 immediately */
43 	memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
44 	skb_put_zero(skb, 2); /* append QoS control field */
45 	ieee80211_mps_set_frame_flags(sdata, sta, nullfunc);
46 
47 	return skb;
48 }
49 
50 /**
51  * mps_qos_null_tx - send a QoS Null to indicate link-specific power mode
52  * @sta: the station to send to
53  */
54 static void mps_qos_null_tx(struct sta_info *sta)
55 {
56 	struct sk_buff *skb;
57 
58 	skb = mps_qos_null_get(sta);
59 	if (!skb)
60 		return;
61 
62 	mps_dbg(sta->sdata, "announcing peer-specific power mode to %pM\n",
63 		sta->sta.addr);
64 
65 	/* don't unintentionally start a MPSP */
66 	if (!test_sta_flag(sta, WLAN_STA_PS_STA)) {
67 		u8 *qc = ieee80211_get_qos_ctl((void *) skb->data);
68 
69 		qc[0] |= IEEE80211_QOS_CTL_EOSP;
70 	}
71 
72 	ieee80211_tx_skb(sta->sdata, skb);
73 }
74 
75 /**
76  * ieee80211_mps_local_status_update - track status of local link-specific PMs
77  *
78  * @sdata: local mesh subif
79  *
80  * sets the non-peer power mode and triggers the driver PS (re-)configuration
81  * Return BSS_CHANGED_BEACON if a beacon update is necessary.
82  *
83  * Returns: BSS_CHANGED_BEACON if a beacon update is in order.
84  */
85 u64 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata)
86 {
87 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
88 	struct sta_info *sta;
89 	bool peering = false;
90 	int light_sleep_cnt = 0;
91 	int deep_sleep_cnt = 0;
92 	u64 changed = 0;
93 	enum nl80211_mesh_power_mode nonpeer_pm;
94 
95 	rcu_read_lock();
96 	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
97 		if (sdata != sta->sdata)
98 			continue;
99 
100 		switch (sta->mesh->plink_state) {
101 		case NL80211_PLINK_OPN_SNT:
102 		case NL80211_PLINK_OPN_RCVD:
103 		case NL80211_PLINK_CNF_RCVD:
104 			peering = true;
105 			break;
106 		case NL80211_PLINK_ESTAB:
107 			if (sta->mesh->local_pm == NL80211_MESH_POWER_LIGHT_SLEEP)
108 				light_sleep_cnt++;
109 			else if (sta->mesh->local_pm == NL80211_MESH_POWER_DEEP_SLEEP)
110 				deep_sleep_cnt++;
111 			break;
112 		default:
113 			break;
114 		}
115 	}
116 	rcu_read_unlock();
117 
118 	/*
119 	 * Set non-peer mode to active during peering/scanning/authentication
120 	 * (see IEEE802.11-2012 13.14.8.3). The non-peer mesh power mode is
121 	 * deep sleep if the local STA is in light or deep sleep towards at
122 	 * least one mesh peer (see 13.14.3.1). Otherwise, set it to the
123 	 * user-configured default value.
124 	 */
125 	if (peering) {
126 		mps_dbg(sdata, "setting non-peer PM to active for peering\n");
127 		nonpeer_pm = NL80211_MESH_POWER_ACTIVE;
128 	} else if (light_sleep_cnt || deep_sleep_cnt) {
129 		mps_dbg(sdata, "setting non-peer PM to deep sleep\n");
130 		nonpeer_pm = NL80211_MESH_POWER_DEEP_SLEEP;
131 	} else {
132 		mps_dbg(sdata, "setting non-peer PM to user value\n");
133 		nonpeer_pm = ifmsh->mshcfg.power_mode;
134 	}
135 
136 	/* need update if sleep counts move between 0 and non-zero */
137 	if (ifmsh->nonpeer_pm != nonpeer_pm ||
138 	    !ifmsh->ps_peers_light_sleep != !light_sleep_cnt ||
139 	    !ifmsh->ps_peers_deep_sleep != !deep_sleep_cnt)
140 		changed = BSS_CHANGED_BEACON;
141 
142 	ifmsh->nonpeer_pm = nonpeer_pm;
143 	ifmsh->ps_peers_light_sleep = light_sleep_cnt;
144 	ifmsh->ps_peers_deep_sleep = deep_sleep_cnt;
145 
146 	return changed;
147 }
148 
149 /**
150  * ieee80211_mps_set_sta_local_pm - set local PM towards a mesh STA
151  *
152  * @sta: mesh STA
153  * @pm: the power mode to set
154  * Returns: BSS_CHANGED_BEACON if a beacon update is in order.
155  */
156 u64 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
157 				   enum nl80211_mesh_power_mode pm)
158 {
159 	struct ieee80211_sub_if_data *sdata = sta->sdata;
160 
161 	if (sta->mesh->local_pm == pm)
162 		return 0;
163 
164 	mps_dbg(sdata, "local STA operates in mode %d with %pM\n",
165 		pm, sta->sta.addr);
166 
167 	sta->mesh->local_pm = pm;
168 
169 	/*
170 	 * announce peer-specific power mode transition
171 	 * (see IEEE802.11-2012 13.14.3.2 and 13.14.3.3)
172 	 */
173 	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
174 		mps_qos_null_tx(sta);
175 
176 	return ieee80211_mps_local_status_update(sdata);
177 }
178 
179 /**
180  * ieee80211_mps_set_frame_flags - set mesh PS flags in FC (and QoS Control)
181  *
182  * @sdata: local mesh subif
183  * @sta: mesh STA
184  * @hdr: 802.11 frame header
185  *
186  * see IEEE802.11-2012 8.2.4.1.7 and 8.2.4.5.11
187  *
188  * NOTE: sta must be given when an individually-addressed QoS frame header
189  * is handled, for group-addressed and management frames it is not used
190  */
191 void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
192 				   struct sta_info *sta,
193 				   struct ieee80211_hdr *hdr)
194 {
195 	enum nl80211_mesh_power_mode pm;
196 	u8 *qc;
197 
198 	if (WARN_ON(is_unicast_ether_addr(hdr->addr1) &&
199 		    ieee80211_is_data_qos(hdr->frame_control) &&
200 		    !sta))
201 		return;
202 
203 	if (is_unicast_ether_addr(hdr->addr1) &&
204 	    ieee80211_is_data_qos(hdr->frame_control) &&
205 	    sta->mesh->plink_state == NL80211_PLINK_ESTAB)
206 		pm = sta->mesh->local_pm;
207 	else
208 		pm = sdata->u.mesh.nonpeer_pm;
209 
210 	if (pm == NL80211_MESH_POWER_ACTIVE)
211 		hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_PM);
212 	else
213 		hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
214 
215 	if (!ieee80211_is_data_qos(hdr->frame_control))
216 		return;
217 
218 	qc = ieee80211_get_qos_ctl(hdr);
219 
220 	if ((is_unicast_ether_addr(hdr->addr1) &&
221 	     pm == NL80211_MESH_POWER_DEEP_SLEEP) ||
222 	    (is_multicast_ether_addr(hdr->addr1) &&
223 	     sdata->u.mesh.ps_peers_deep_sleep > 0))
224 		qc[1] |= (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
225 	else
226 		qc[1] &= ~(IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
227 }
228 
229 /**
230  * ieee80211_mps_sta_status_update - update buffering status of neighbor STA
231  *
232  * @sta: mesh STA
233  *
234  * called after change of peering status or non-peer/peer-specific power mode
235  */
236 void ieee80211_mps_sta_status_update(struct sta_info *sta)
237 {
238 	enum nl80211_mesh_power_mode pm;
239 	bool do_buffer;
240 
241 	/* For non-assoc STA, prevent buffering or frame transmission */
242 	if (sta->sta_state < IEEE80211_STA_ASSOC)
243 		return;
244 
245 	/*
246 	 * use peer-specific power mode if peering is established and the
247 	 * peer's power mode is known
248 	 */
249 	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
250 	    sta->mesh->peer_pm != NL80211_MESH_POWER_UNKNOWN)
251 		pm = sta->mesh->peer_pm;
252 	else
253 		pm = sta->mesh->nonpeer_pm;
254 
255 	do_buffer = (pm != NL80211_MESH_POWER_ACTIVE);
256 
257 	/* clear the MPSP flags for non-peers or active STA */
258 	if (sta->mesh->plink_state != NL80211_PLINK_ESTAB) {
259 		clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
260 		clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
261 	} else if (!do_buffer) {
262 		clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
263 	}
264 
265 	/* Don't let the same PS state be set twice */
266 	if (test_sta_flag(sta, WLAN_STA_PS_STA) == do_buffer)
267 		return;
268 
269 	if (do_buffer) {
270 		set_sta_flag(sta, WLAN_STA_PS_STA);
271 		atomic_inc(&sta->sdata->u.mesh.ps.num_sta_ps);
272 		mps_dbg(sta->sdata, "start PS buffering frames towards %pM\n",
273 			sta->sta.addr);
274 	} else {
275 		ieee80211_sta_ps_deliver_wakeup(sta);
276 	}
277 }
278 
279 static void mps_set_sta_peer_pm(struct sta_info *sta,
280 				struct ieee80211_hdr *hdr)
281 {
282 	enum nl80211_mesh_power_mode pm;
283 	u8 *qc = ieee80211_get_qos_ctl(hdr);
284 
285 	/*
286 	 * Test Power Management field of frame control (PW) and
287 	 * mesh power save level subfield of QoS control field (PSL)
288 	 *
289 	 * | PM | PSL| Mesh PM |
290 	 * +----+----+---------+
291 	 * | 0  |Rsrv|  Active |
292 	 * | 1  | 0  |  Light  |
293 	 * | 1  | 1  |  Deep   |
294 	 */
295 	if (ieee80211_has_pm(hdr->frame_control)) {
296 		if (qc[1] & (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8))
297 			pm = NL80211_MESH_POWER_DEEP_SLEEP;
298 		else
299 			pm = NL80211_MESH_POWER_LIGHT_SLEEP;
300 	} else {
301 		pm = NL80211_MESH_POWER_ACTIVE;
302 	}
303 
304 	if (sta->mesh->peer_pm == pm)
305 		return;
306 
307 	mps_dbg(sta->sdata, "STA %pM enters mode %d\n",
308 		sta->sta.addr, pm);
309 
310 	sta->mesh->peer_pm = pm;
311 
312 	ieee80211_mps_sta_status_update(sta);
313 }
314 
315 static void mps_set_sta_nonpeer_pm(struct sta_info *sta,
316 				   struct ieee80211_hdr *hdr)
317 {
318 	enum nl80211_mesh_power_mode pm;
319 
320 	if (ieee80211_has_pm(hdr->frame_control))
321 		pm = NL80211_MESH_POWER_DEEP_SLEEP;
322 	else
323 		pm = NL80211_MESH_POWER_ACTIVE;
324 
325 	if (sta->mesh->nonpeer_pm == pm)
326 		return;
327 
328 	mps_dbg(sta->sdata, "STA %pM sets non-peer mode to %d\n",
329 		sta->sta.addr, pm);
330 
331 	sta->mesh->nonpeer_pm = pm;
332 
333 	ieee80211_mps_sta_status_update(sta);
334 }
335 
336 /**
337  * ieee80211_mps_rx_h_sta_process - frame receive handler for mesh powersave
338  *
339  * @sta: STA info that transmitted the frame
340  * @hdr: IEEE 802.11 (QoS) Header
341  */
342 void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
343 				    struct ieee80211_hdr *hdr)
344 {
345 	if (is_unicast_ether_addr(hdr->addr1) &&
346 	    ieee80211_is_data_qos(hdr->frame_control)) {
347 		/*
348 		 * individually addressed QoS Data/Null frames contain
349 		 * peer link-specific PS mode towards the local STA
350 		 */
351 		mps_set_sta_peer_pm(sta, hdr);
352 
353 		/* check for mesh Peer Service Period trigger frames */
354 		ieee80211_mpsp_trigger_process(ieee80211_get_qos_ctl(hdr),
355 					       sta, false, false);
356 	} else {
357 		/*
358 		 * can only determine non-peer PS mode
359 		 * (see IEEE802.11-2012 8.2.4.1.7)
360 		 */
361 		mps_set_sta_nonpeer_pm(sta, hdr);
362 	}
363 }
364 
365 
366 /* mesh PS frame release */
367 
368 static void mpsp_trigger_send(struct sta_info *sta, bool rspi, bool eosp)
369 {
370 	struct ieee80211_sub_if_data *sdata = sta->sdata;
371 	struct sk_buff *skb;
372 	struct ieee80211_hdr *nullfunc;
373 	struct ieee80211_tx_info *info;
374 	u8 *qc;
375 
376 	skb = mps_qos_null_get(sta);
377 	if (!skb)
378 		return;
379 
380 	nullfunc = (struct ieee80211_hdr *) skb->data;
381 	if (!eosp)
382 		nullfunc->frame_control |=
383 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
384 	/*
385 	 * | RSPI | EOSP |  MPSP triggering   |
386 	 * +------+------+--------------------+
387 	 * |  0   |  0   | local STA is owner |
388 	 * |  0   |  1   | no MPSP (MPSP end) |
389 	 * |  1   |  0   | both STA are owner |
390 	 * |  1   |  1   | peer STA is owner  | see IEEE802.11-2012 13.14.9.2
391 	 */
392 	qc = ieee80211_get_qos_ctl(nullfunc);
393 	if (rspi)
394 		qc[1] |= (IEEE80211_QOS_CTL_RSPI >> 8);
395 	if (eosp)
396 		qc[0] |= IEEE80211_QOS_CTL_EOSP;
397 
398 	info = IEEE80211_SKB_CB(skb);
399 
400 	info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER |
401 		       IEEE80211_TX_CTL_REQ_TX_STATUS;
402 
403 	mps_dbg(sdata, "sending MPSP trigger%s%s to %pM\n",
404 		rspi ? " RSPI" : "", eosp ? " EOSP" : "", sta->sta.addr);
405 
406 	ieee80211_tx_skb(sdata, skb);
407 }
408 
409 /**
410  * mpsp_qos_null_append - append QoS Null frame to MPSP skb queue if needed
411  * @sta: the station to handle
412  * @frames: the frame list to append to
413  *
414  * To properly end a mesh MPSP the last transmitted frame has to set the EOSP
415  * flag in the QoS Control field. In case the current tailing frame is not a
416  * QoS Data frame, append a QoS Null to carry the flag.
417  */
418 static void mpsp_qos_null_append(struct sta_info *sta,
419 				 struct sk_buff_head *frames)
420 {
421 	struct ieee80211_sub_if_data *sdata = sta->sdata;
422 	struct sk_buff *new_skb, *skb = skb_peek_tail(frames);
423 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
424 	struct ieee80211_tx_info *info;
425 
426 	if (ieee80211_is_data_qos(hdr->frame_control))
427 		return;
428 
429 	new_skb = mps_qos_null_get(sta);
430 	if (!new_skb)
431 		return;
432 
433 	mps_dbg(sdata, "appending QoS Null in MPSP towards %pM\n",
434 		sta->sta.addr);
435 	/*
436 	 * This frame has to be transmitted last. Assign lowest priority to
437 	 * make sure it cannot pass other frames when releasing multiple ACs.
438 	 */
439 	new_skb->priority = 1;
440 	skb_set_queue_mapping(new_skb, IEEE80211_AC_BK);
441 	ieee80211_set_qos_hdr(sdata, new_skb);
442 
443 	info = IEEE80211_SKB_CB(new_skb);
444 	info->control.vif = &sdata->vif;
445 	info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING;
446 
447 	__skb_queue_tail(frames, new_skb);
448 }
449 
450 /**
451  * mps_frame_deliver - transmit frames during mesh powersave
452  *
453  * @sta: STA info to transmit to
454  * @n_frames: number of frames to transmit. -1 for all
455  */
456 static void mps_frame_deliver(struct sta_info *sta, int n_frames)
457 {
458 	struct ieee80211_local *local = sta->sdata->local;
459 	int ac;
460 	struct sk_buff_head frames;
461 	struct sk_buff *skb;
462 	bool more_data = false;
463 
464 	skb_queue_head_init(&frames);
465 
466 	/* collect frame(s) from buffers */
467 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
468 		while (n_frames != 0) {
469 			skb = skb_dequeue(&sta->tx_filtered[ac]);
470 			if (!skb) {
471 				skb = skb_dequeue(
472 					&sta->ps_tx_buf[ac]);
473 				if (skb)
474 					local->total_ps_buffered--;
475 			}
476 			if (!skb)
477 				break;
478 			n_frames--;
479 			__skb_queue_tail(&frames, skb);
480 		}
481 
482 		if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
483 		    !skb_queue_empty(&sta->ps_tx_buf[ac]))
484 			more_data = true;
485 	}
486 
487 	/* nothing to send? -> EOSP */
488 	if (skb_queue_empty(&frames)) {
489 		mpsp_trigger_send(sta, false, true);
490 		return;
491 	}
492 
493 	/* in a MPSP make sure the last skb is a QoS Data frame */
494 	if (test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
495 		mpsp_qos_null_append(sta, &frames);
496 
497 	mps_dbg(sta->sdata, "sending %d frames to PS STA %pM\n",
498 		skb_queue_len(&frames), sta->sta.addr);
499 
500 	/* prepare collected frames for transmission */
501 	skb_queue_walk(&frames, skb) {
502 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
503 		struct ieee80211_hdr *hdr = (void *) skb->data;
504 
505 		/*
506 		 * Tell TX path to send this frame even though the
507 		 * STA may still remain is PS mode after this frame
508 		 * exchange.
509 		 */
510 		info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
511 
512 		if (more_data || !skb_queue_is_last(&frames, skb))
513 			hdr->frame_control |=
514 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
515 		else
516 			hdr->frame_control &=
517 				cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
518 
519 		if (skb_queue_is_last(&frames, skb) &&
520 		    ieee80211_is_data_qos(hdr->frame_control)) {
521 			u8 *qoshdr = ieee80211_get_qos_ctl(hdr);
522 
523 			/* MPSP trigger frame ends service period */
524 			*qoshdr |= IEEE80211_QOS_CTL_EOSP;
525 			info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
526 		}
527 	}
528 
529 	ieee80211_add_pending_skbs(local, &frames);
530 	sta_info_recalc_tim(sta);
531 }
532 
533 /**
534  * ieee80211_mpsp_trigger_process - track status of mesh Peer Service Periods
535  *
536  * @qc: QoS Control field
537  * @sta: peer to start a MPSP with
538  * @tx: frame was transmitted by the local STA
539  * @acked: frame has been transmitted successfully
540  *
541  * NOTE: active mode STA may only serve as MPSP owner
542  */
543 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
544 				    bool tx, bool acked)
545 {
546 	u8 rspi = qc[1] & (IEEE80211_QOS_CTL_RSPI >> 8);
547 	u8 eosp = qc[0] & IEEE80211_QOS_CTL_EOSP;
548 
549 	if (tx) {
550 		if (rspi && acked)
551 			set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
552 
553 		if (eosp)
554 			clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
555 		else if (acked &&
556 			 test_sta_flag(sta, WLAN_STA_PS_STA) &&
557 			 !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
558 			mps_frame_deliver(sta, -1);
559 	} else {
560 		if (eosp)
561 			clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
562 		else if (sta->mesh->local_pm != NL80211_MESH_POWER_ACTIVE)
563 			set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
564 
565 		if (rspi && !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
566 			mps_frame_deliver(sta, -1);
567 	}
568 }
569 
570 /**
571  * ieee80211_mps_frame_release - release frames buffered due to mesh power save
572  *
573  * @sta: mesh STA
574  * @elems: IEs of beacon or probe response
575  *
576  * For peers if we have individually-addressed frames buffered or the peer
577  * indicates buffered frames, send a corresponding MPSP trigger frame. Since
578  * we do not evaluate the awake window duration, QoS Nulls are used as MPSP
579  * trigger frames. If the neighbour STA is not a peer, only send single frames.
580  */
581 void ieee80211_mps_frame_release(struct sta_info *sta,
582 				 struct ieee802_11_elems *elems)
583 {
584 	int ac, buffer_local = 0;
585 	bool has_buffered = false;
586 
587 	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
588 		has_buffered = ieee80211_check_tim(elems->tim, elems->tim_len,
589 						   sta->mesh->aid);
590 
591 	if (has_buffered)
592 		mps_dbg(sta->sdata, "%pM indicates buffered frames\n",
593 			sta->sta.addr);
594 
595 	/* only transmit to PS STA with announced, non-zero awake window */
596 	if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
597 	    (!elems->awake_window || !get_unaligned_le16(elems->awake_window)))
598 		return;
599 
600 	if (!test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
601 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
602 			buffer_local += skb_queue_len(&sta->ps_tx_buf[ac]) +
603 					skb_queue_len(&sta->tx_filtered[ac]);
604 
605 	if (!has_buffered && !buffer_local)
606 		return;
607 
608 	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
609 		mpsp_trigger_send(sta, has_buffered, !buffer_local);
610 	else
611 		mps_frame_deliver(sta, 1);
612 }
613