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   */
mps_qos_null_get(struct sta_info * sta)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   */
mps_qos_null_tx(struct sta_info * sta)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   */
ieee80211_mps_local_status_update(struct ieee80211_sub_if_data * sdata)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   */
ieee80211_mps_set_sta_local_pm(struct sta_info * sta,enum nl80211_mesh_power_mode pm)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   */
ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,struct ieee80211_hdr * hdr)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   */
ieee80211_mps_sta_status_update(struct sta_info * sta)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  
mps_set_sta_peer_pm(struct sta_info * sta,struct ieee80211_hdr * hdr)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  
mps_set_sta_nonpeer_pm(struct sta_info * sta,struct ieee80211_hdr * hdr)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   */
ieee80211_mps_rx_h_sta_process(struct sta_info * sta,struct ieee80211_hdr * hdr)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  
mpsp_trigger_send(struct sta_info * sta,bool rspi,bool eosp)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   */
mpsp_qos_null_append(struct sta_info * sta,struct sk_buff_head * frames)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   */
mps_frame_deliver(struct sta_info * sta,int n_frames)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   */
ieee80211_mpsp_trigger_process(u8 * qc,struct sta_info * sta,bool tx,bool acked)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   */
ieee80211_mps_frame_release(struct sta_info * sta,struct ieee802_11_elems * elems)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