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  */
7 
8 #include "mesh.h"
9 #include "wme.h"
10 
11 
12 /* mesh PS management */
13 
14 /**
15  * mps_qos_null_get - create pre-addressed QoS Null frame for mesh powersave
16  * @sta: the station to get the frame for
17  */
mps_qos_null_get(struct sta_info * sta)18 static struct sk_buff *mps_qos_null_get(struct sta_info *sta)
19 {
20 	struct ieee80211_sub_if_data *sdata = sta->sdata;
21 	struct ieee80211_local *local = sdata->local;
22 	struct ieee80211_hdr *nullfunc; /* use 4addr header */
23 	struct sk_buff *skb;
24 	int size = sizeof(*nullfunc);
25 	__le16 fc;
26 
27 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + size + 2);
28 	if (!skb)
29 		return NULL;
30 	skb_reserve(skb, local->hw.extra_tx_headroom);
31 
32 	nullfunc = skb_put(skb, size);
33 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_QOS_NULLFUNC);
34 	ieee80211_fill_mesh_addresses(nullfunc, &fc, sta->sta.addr,
35 				      sdata->vif.addr);
36 	nullfunc->frame_control = fc;
37 	nullfunc->duration_id = 0;
38 	nullfunc->seq_ctrl = 0;
39 	/* no address resolution for this frame -> set addr 1 immediately */
40 	memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
41 	skb_put_zero(skb, 2); /* append QoS control field */
42 	ieee80211_mps_set_frame_flags(sdata, sta, nullfunc);
43 
44 	return skb;
45 }
46 
47 /**
48  * mps_qos_null_tx - send a QoS Null to indicate link-specific power mode
49  * @sta: the station to send to
50  */
mps_qos_null_tx(struct sta_info * sta)51 static 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  */
ieee80211_mps_local_status_update(struct ieee80211_sub_if_data * sdata)80 u32 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  */
ieee80211_mps_set_sta_local_pm(struct sta_info * sta,enum nl80211_mesh_power_mode pm)151 u32 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  */
ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,struct ieee80211_hdr * hdr)186 void 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  */
ieee80211_mps_sta_status_update(struct sta_info * sta)231 void 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 
mps_set_sta_peer_pm(struct sta_info * sta,struct ieee80211_hdr * hdr)274 static 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 
mps_set_sta_nonpeer_pm(struct sta_info * sta,struct ieee80211_hdr * hdr)310 static 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  */
ieee80211_mps_rx_h_sta_process(struct sta_info * sta,struct ieee80211_hdr * hdr)337 void 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 
mpsp_trigger_send(struct sta_info * sta,bool rspi,bool eosp)363 static 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  * @sta: the station to handle
407  * @frames: the frame list to append to
408  *
409  * To properly end a mesh MPSP the last transmitted frame has to set the EOSP
410  * flag in the QoS Control field. In case the current tailing frame is not a
411  * QoS Data frame, append a QoS Null to carry the flag.
412  */
mpsp_qos_null_append(struct sta_info * sta,struct sk_buff_head * frames)413 static void mpsp_qos_null_append(struct sta_info *sta,
414 				 struct sk_buff_head *frames)
415 {
416 	struct ieee80211_sub_if_data *sdata = sta->sdata;
417 	struct sk_buff *new_skb, *skb = skb_peek_tail(frames);
418 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
419 	struct ieee80211_tx_info *info;
420 
421 	if (ieee80211_is_data_qos(hdr->frame_control))
422 		return;
423 
424 	new_skb = mps_qos_null_get(sta);
425 	if (!new_skb)
426 		return;
427 
428 	mps_dbg(sdata, "appending QoS Null in MPSP towards %pM\n",
429 		sta->sta.addr);
430 	/*
431 	 * This frame has to be transmitted last. Assign lowest priority to
432 	 * make sure it cannot pass other frames when releasing multiple ACs.
433 	 */
434 	new_skb->priority = 1;
435 	skb_set_queue_mapping(new_skb, IEEE80211_AC_BK);
436 	ieee80211_set_qos_hdr(sdata, new_skb);
437 
438 	info = IEEE80211_SKB_CB(new_skb);
439 	info->control.vif = &sdata->vif;
440 	info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING;
441 
442 	__skb_queue_tail(frames, new_skb);
443 }
444 
445 /**
446  * mps_frame_deliver - transmit frames during mesh powersave
447  *
448  * @sta: STA info to transmit to
449  * @n_frames: number of frames to transmit. -1 for all
450  */
mps_frame_deliver(struct sta_info * sta,int n_frames)451 static void mps_frame_deliver(struct sta_info *sta, int n_frames)
452 {
453 	struct ieee80211_local *local = sta->sdata->local;
454 	int ac;
455 	struct sk_buff_head frames;
456 	struct sk_buff *skb;
457 	bool more_data = false;
458 
459 	skb_queue_head_init(&frames);
460 
461 	/* collect frame(s) from buffers */
462 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
463 		while (n_frames != 0) {
464 			skb = skb_dequeue(&sta->tx_filtered[ac]);
465 			if (!skb) {
466 				skb = skb_dequeue(
467 					&sta->ps_tx_buf[ac]);
468 				if (skb)
469 					local->total_ps_buffered--;
470 			}
471 			if (!skb)
472 				break;
473 			n_frames--;
474 			__skb_queue_tail(&frames, skb);
475 		}
476 
477 		if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
478 		    !skb_queue_empty(&sta->ps_tx_buf[ac]))
479 			more_data = true;
480 	}
481 
482 	/* nothing to send? -> EOSP */
483 	if (skb_queue_empty(&frames)) {
484 		mpsp_trigger_send(sta, false, true);
485 		return;
486 	}
487 
488 	/* in a MPSP make sure the last skb is a QoS Data frame */
489 	if (test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
490 		mpsp_qos_null_append(sta, &frames);
491 
492 	mps_dbg(sta->sdata, "sending %d frames to PS STA %pM\n",
493 		skb_queue_len(&frames), sta->sta.addr);
494 
495 	/* prepare collected frames for transmission */
496 	skb_queue_walk(&frames, skb) {
497 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
498 		struct ieee80211_hdr *hdr = (void *) skb->data;
499 
500 		/*
501 		 * Tell TX path to send this frame even though the
502 		 * STA may still remain is PS mode after this frame
503 		 * exchange.
504 		 */
505 		info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
506 
507 		if (more_data || !skb_queue_is_last(&frames, skb))
508 			hdr->frame_control |=
509 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
510 		else
511 			hdr->frame_control &=
512 				cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
513 
514 		if (skb_queue_is_last(&frames, skb) &&
515 		    ieee80211_is_data_qos(hdr->frame_control)) {
516 			u8 *qoshdr = ieee80211_get_qos_ctl(hdr);
517 
518 			/* MPSP trigger frame ends service period */
519 			*qoshdr |= IEEE80211_QOS_CTL_EOSP;
520 			info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
521 		}
522 	}
523 
524 	ieee80211_add_pending_skbs(local, &frames);
525 	sta_info_recalc_tim(sta);
526 }
527 
528 /**
529  * ieee80211_mpsp_trigger_process - track status of mesh Peer Service Periods
530  *
531  * @qc: QoS Control field
532  * @sta: peer to start a MPSP with
533  * @tx: frame was transmitted by the local STA
534  * @acked: frame has been transmitted successfully
535  *
536  * NOTE: active mode STA may only serve as MPSP owner
537  */
ieee80211_mpsp_trigger_process(u8 * qc,struct sta_info * sta,bool tx,bool acked)538 void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
539 				    bool tx, bool acked)
540 {
541 	u8 rspi = qc[1] & (IEEE80211_QOS_CTL_RSPI >> 8);
542 	u8 eosp = qc[0] & IEEE80211_QOS_CTL_EOSP;
543 
544 	if (tx) {
545 		if (rspi && acked)
546 			set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
547 
548 		if (eosp)
549 			clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
550 		else if (acked &&
551 			 test_sta_flag(sta, WLAN_STA_PS_STA) &&
552 			 !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
553 			mps_frame_deliver(sta, -1);
554 	} else {
555 		if (eosp)
556 			clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
557 		else if (sta->mesh->local_pm != NL80211_MESH_POWER_ACTIVE)
558 			set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
559 
560 		if (rspi && !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
561 			mps_frame_deliver(sta, -1);
562 	}
563 }
564 
565 /**
566  * ieee80211_mps_frame_release - release frames buffered due to mesh power save
567  *
568  * @sta: mesh STA
569  * @elems: IEs of beacon or probe response
570  *
571  * For peers if we have individually-addressed frames buffered or the peer
572  * indicates buffered frames, send a corresponding MPSP trigger frame. Since
573  * we do not evaluate the awake window duration, QoS Nulls are used as MPSP
574  * trigger frames. If the neighbour STA is not a peer, only send single frames.
575  */
ieee80211_mps_frame_release(struct sta_info * sta,struct ieee802_11_elems * elems)576 void ieee80211_mps_frame_release(struct sta_info *sta,
577 				 struct ieee802_11_elems *elems)
578 {
579 	int ac, buffer_local = 0;
580 	bool has_buffered = false;
581 
582 	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
583 		has_buffered = ieee80211_check_tim(elems->tim, elems->tim_len,
584 						   sta->mesh->aid);
585 
586 	if (has_buffered)
587 		mps_dbg(sta->sdata, "%pM indicates buffered frames\n",
588 			sta->sta.addr);
589 
590 	/* only transmit to PS STA with announced, non-zero awake window */
591 	if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
592 	    (!elems->awake_window || !get_unaligned_le16(elems->awake_window)))
593 		return;
594 
595 	if (!test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
596 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
597 			buffer_local += skb_queue_len(&sta->ps_tx_buf[ac]) +
598 					skb_queue_len(&sta->tx_filtered[ac]);
599 
600 	if (!has_buffered && !buffer_local)
601 		return;
602 
603 	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
604 		mpsp_trigger_send(sta, has_buffered, !buffer_local);
605 	else
606 		mps_frame_deliver(sta, 1);
607 }
608