xref: /openbmc/linux/net/mac80211/status.c (revision bc000245)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2008-2010	Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/export.h>
13 #include <linux/etherdevice.h>
14 #include <net/mac80211.h>
15 #include <asm/unaligned.h>
16 #include "ieee80211_i.h"
17 #include "rate.h"
18 #include "mesh.h"
19 #include "led.h"
20 #include "wme.h"
21 
22 
23 void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
24 				 struct sk_buff *skb)
25 {
26 	struct ieee80211_local *local = hw_to_local(hw);
27 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
28 	int tmp;
29 
30 	skb->pkt_type = IEEE80211_TX_STATUS_MSG;
31 	skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
32 		       &local->skb_queue : &local->skb_queue_unreliable, skb);
33 	tmp = skb_queue_len(&local->skb_queue) +
34 		skb_queue_len(&local->skb_queue_unreliable);
35 	while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
36 	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
37 		ieee80211_free_txskb(hw, skb);
38 		tmp--;
39 		I802_DEBUG_INC(local->tx_status_drop);
40 	}
41 	tasklet_schedule(&local->tasklet);
42 }
43 EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
44 
45 static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
46 					    struct sta_info *sta,
47 					    struct sk_buff *skb)
48 {
49 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
50 	struct ieee80211_hdr *hdr = (void *)skb->data;
51 	int ac;
52 
53 	/*
54 	 * This skb 'survived' a round-trip through the driver, and
55 	 * hopefully the driver didn't mangle it too badly. However,
56 	 * we can definitely not rely on the control information
57 	 * being correct. Clear it so we don't get junk there, and
58 	 * indicate that it needs new processing, but must not be
59 	 * modified/encrypted again.
60 	 */
61 	memset(&info->control, 0, sizeof(info->control));
62 
63 	info->control.jiffies = jiffies;
64 	info->control.vif = &sta->sdata->vif;
65 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
66 		       IEEE80211_TX_INTFL_RETRANSMISSION;
67 	info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
68 
69 	sta->tx_filtered_count++;
70 
71 	/*
72 	 * Clear more-data bit on filtered frames, it might be set
73 	 * but later frames might time out so it might have to be
74 	 * clear again ... It's all rather unlikely (this frame
75 	 * should time out first, right?) but let's not confuse
76 	 * peers unnecessarily.
77 	 */
78 	if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
79 		hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);
80 
81 	if (ieee80211_is_data_qos(hdr->frame_control)) {
82 		u8 *p = ieee80211_get_qos_ctl(hdr);
83 		int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
84 
85 		/*
86 		 * Clear EOSP if set, this could happen e.g.
87 		 * if an absence period (us being a P2P GO)
88 		 * shortens the SP.
89 		 */
90 		if (*p & IEEE80211_QOS_CTL_EOSP)
91 			*p &= ~IEEE80211_QOS_CTL_EOSP;
92 		ac = ieee802_1d_to_ac[tid & 7];
93 	} else {
94 		ac = IEEE80211_AC_BE;
95 	}
96 
97 	/*
98 	 * Clear the TX filter mask for this STA when sending the next
99 	 * packet. If the STA went to power save mode, this will happen
100 	 * when it wakes up for the next time.
101 	 */
102 	set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
103 
104 	/*
105 	 * This code races in the following way:
106 	 *
107 	 *  (1) STA sends frame indicating it will go to sleep and does so
108 	 *  (2) hardware/firmware adds STA to filter list, passes frame up
109 	 *  (3) hardware/firmware processes TX fifo and suppresses a frame
110 	 *  (4) we get TX status before having processed the frame and
111 	 *	knowing that the STA has gone to sleep.
112 	 *
113 	 * This is actually quite unlikely even when both those events are
114 	 * processed from interrupts coming in quickly after one another or
115 	 * even at the same time because we queue both TX status events and
116 	 * RX frames to be processed by a tasklet and process them in the
117 	 * same order that they were received or TX status last. Hence, there
118 	 * is no race as long as the frame RX is processed before the next TX
119 	 * status, which drivers can ensure, see below.
120 	 *
121 	 * Note that this can only happen if the hardware or firmware can
122 	 * actually add STAs to the filter list, if this is done by the
123 	 * driver in response to set_tim() (which will only reduce the race
124 	 * this whole filtering tries to solve, not completely solve it)
125 	 * this situation cannot happen.
126 	 *
127 	 * To completely solve this race drivers need to make sure that they
128 	 *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
129 	 *	functions and
130 	 *  (b) always process RX events before TX status events if ordering
131 	 *      can be unknown, for example with different interrupt status
132 	 *	bits.
133 	 *  (c) if PS mode transitions are manual (i.e. the flag
134 	 *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
135 	 *      changes before calling TX status events if ordering can be
136 	 *	unknown.
137 	 */
138 	if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
139 	    skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
140 		skb_queue_tail(&sta->tx_filtered[ac], skb);
141 		sta_info_recalc_tim(sta);
142 
143 		if (!timer_pending(&local->sta_cleanup))
144 			mod_timer(&local->sta_cleanup,
145 				  round_jiffies(jiffies +
146 						STA_INFO_CLEANUP_INTERVAL));
147 		return;
148 	}
149 
150 	if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
151 	    !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
152 		/* Software retry the packet once */
153 		info->flags |= IEEE80211_TX_INTFL_RETRIED;
154 		ieee80211_add_pending_skb(local, skb);
155 		return;
156 	}
157 
158 	ps_dbg_ratelimited(sta->sdata,
159 			   "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
160 			   skb_queue_len(&sta->tx_filtered[ac]),
161 			   !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);
162 	ieee80211_free_txskb(&local->hw, skb);
163 }
164 
165 static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
166 {
167 	struct tid_ampdu_tx *tid_tx;
168 
169 	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
170 	if (!tid_tx || !tid_tx->bar_pending)
171 		return;
172 
173 	tid_tx->bar_pending = false;
174 	ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);
175 }
176 
177 static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
178 {
179 	struct ieee80211_mgmt *mgmt = (void *) skb->data;
180 	struct ieee80211_local *local = sta->local;
181 	struct ieee80211_sub_if_data *sdata = sta->sdata;
182 
183 	if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)
184 		sta->last_rx = jiffies;
185 
186 	if (ieee80211_is_data_qos(mgmt->frame_control)) {
187 		struct ieee80211_hdr *hdr = (void *) skb->data;
188 		u8 *qc = ieee80211_get_qos_ctl(hdr);
189 		u16 tid = qc[0] & 0xf;
190 
191 		ieee80211_check_pending_bar(sta, hdr->addr1, tid);
192 	}
193 
194 	if (ieee80211_is_action(mgmt->frame_control) &&
195 	    mgmt->u.action.category == WLAN_CATEGORY_HT &&
196 	    mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
197 	    ieee80211_sdata_running(sdata)) {
198 		enum ieee80211_smps_mode smps_mode;
199 
200 		switch (mgmt->u.action.u.ht_smps.smps_control) {
201 		case WLAN_HT_SMPS_CONTROL_DYNAMIC:
202 			smps_mode = IEEE80211_SMPS_DYNAMIC;
203 			break;
204 		case WLAN_HT_SMPS_CONTROL_STATIC:
205 			smps_mode = IEEE80211_SMPS_STATIC;
206 			break;
207 		case WLAN_HT_SMPS_CONTROL_DISABLED:
208 		default: /* shouldn't happen since we don't send that */
209 			smps_mode = IEEE80211_SMPS_OFF;
210 			break;
211 		}
212 
213 		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
214 			/*
215 			 * This update looks racy, but isn't -- if we come
216 			 * here we've definitely got a station that we're
217 			 * talking to, and on a managed interface that can
218 			 * only be the AP. And the only other place updating
219 			 * this variable in managed mode is before association.
220 			 */
221 			sdata->smps_mode = smps_mode;
222 			ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
223 		} else if (sdata->vif.type == NL80211_IFTYPE_AP ||
224 			   sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
225 			sta->known_smps_mode = smps_mode;
226 		}
227 	}
228 }
229 
230 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
231 {
232 	struct tid_ampdu_tx *tid_tx;
233 
234 	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
235 	if (!tid_tx)
236 		return;
237 
238 	tid_tx->failed_bar_ssn = ssn;
239 	tid_tx->bar_pending = true;
240 }
241 
242 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
243 {
244 	int len = sizeof(struct ieee80211_radiotap_header);
245 
246 	/* IEEE80211_RADIOTAP_RATE rate */
247 	if (info->status.rates[0].idx >= 0 &&
248 	    !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
249 					     IEEE80211_TX_RC_VHT_MCS)))
250 		len += 2;
251 
252 	/* IEEE80211_RADIOTAP_TX_FLAGS */
253 	len += 2;
254 
255 	/* IEEE80211_RADIOTAP_DATA_RETRIES */
256 	len += 1;
257 
258 	/* IEEE80211_RADIOTAP_MCS
259 	 * IEEE80211_RADIOTAP_VHT */
260 	if (info->status.rates[0].idx >= 0) {
261 		if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
262 			len += 3;
263 		else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
264 			len = ALIGN(len, 2) + 12;
265 	}
266 
267 	return len;
268 }
269 
270 static void
271 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
272 				 struct ieee80211_supported_band *sband,
273 				 struct sk_buff *skb, int retry_count,
274 				 int rtap_len, int shift)
275 {
276 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
277 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
278 	struct ieee80211_radiotap_header *rthdr;
279 	unsigned char *pos;
280 	u16 txflags;
281 
282 	rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len);
283 
284 	memset(rthdr, 0, rtap_len);
285 	rthdr->it_len = cpu_to_le16(rtap_len);
286 	rthdr->it_present =
287 		cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
288 			    (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
289 	pos = (unsigned char *)(rthdr + 1);
290 
291 	/*
292 	 * XXX: Once radiotap gets the bitmap reset thing the vendor
293 	 *	extensions proposal contains, we can actually report
294 	 *	the whole set of tries we did.
295 	 */
296 
297 	/* IEEE80211_RADIOTAP_RATE */
298 	if (info->status.rates[0].idx >= 0 &&
299 	    !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
300 					     IEEE80211_TX_RC_VHT_MCS))) {
301 		u16 rate;
302 
303 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
304 		rate = sband->bitrates[info->status.rates[0].idx].bitrate;
305 		*pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
306 		/* padding for tx flags */
307 		pos += 2;
308 	}
309 
310 	/* IEEE80211_RADIOTAP_TX_FLAGS */
311 	txflags = 0;
312 	if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
313 	    !is_multicast_ether_addr(hdr->addr1))
314 		txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
315 
316 	if ((info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
317 	    (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
318 		txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
319 	else if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
320 		txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
321 
322 	put_unaligned_le16(txflags, pos);
323 	pos += 2;
324 
325 	/* IEEE80211_RADIOTAP_DATA_RETRIES */
326 	/* for now report the total retry_count */
327 	*pos = retry_count;
328 	pos++;
329 
330 	if (info->status.rates[0].idx < 0)
331 		return;
332 
333 	/* IEEE80211_RADIOTAP_MCS
334 	 * IEEE80211_RADIOTAP_VHT */
335 	if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
336 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
337 		pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
338 			 IEEE80211_RADIOTAP_MCS_HAVE_GI |
339 			 IEEE80211_RADIOTAP_MCS_HAVE_BW;
340 		if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
341 			pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
342 		if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
343 			pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
344 		if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
345 			pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
346 		pos[2] = info->status.rates[0].idx;
347 		pos += 3;
348 	} else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
349 		u16 known = local->hw.radiotap_vht_details &
350 			(IEEE80211_RADIOTAP_VHT_KNOWN_GI |
351 			 IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
352 
353 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
354 
355 		/* required alignment from rthdr */
356 		pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
357 
358 		/* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
359 		put_unaligned_le16(known, pos);
360 		pos += 2;
361 
362 		/* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
363 		if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
364 			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
365 		pos++;
366 
367 		/* u8 bandwidth */
368 		if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
369 			*pos = 1;
370 		else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
371 			*pos = 4;
372 		else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
373 			*pos = 11;
374 		else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
375 			*pos = 0;
376 		pos++;
377 
378 		/* u8 mcs_nss[4] */
379 		*pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
380 			ieee80211_rate_get_vht_nss(&info->status.rates[0]);
381 		pos += 4;
382 
383 		/* u8 coding */
384 		pos++;
385 		/* u8 group_id */
386 		pos++;
387 		/* u16 partial_aid */
388 		pos += 2;
389 	}
390 }
391 
392 static void ieee80211_report_used_skb(struct ieee80211_local *local,
393 				      struct sk_buff *skb, bool dropped)
394 {
395 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
396 	struct ieee80211_hdr *hdr = (void *)skb->data;
397 	bool acked = info->flags & IEEE80211_TX_STAT_ACK;
398 
399 	if (dropped)
400 		acked = false;
401 
402 	if (info->flags & (IEEE80211_TX_INTFL_NL80211_FRAME_TX |
403 			   IEEE80211_TX_INTFL_MLME_CONN_TX)) {
404 		struct ieee80211_sub_if_data *sdata = NULL;
405 		struct ieee80211_sub_if_data *iter_sdata;
406 		u64 cookie = (unsigned long)skb;
407 
408 		rcu_read_lock();
409 
410 		if (skb->dev) {
411 			list_for_each_entry_rcu(iter_sdata, &local->interfaces,
412 						list) {
413 				if (!iter_sdata->dev)
414 					continue;
415 
416 				if (skb->dev == iter_sdata->dev) {
417 					sdata = iter_sdata;
418 					break;
419 				}
420 			}
421 		} else {
422 			sdata = rcu_dereference(local->p2p_sdata);
423 		}
424 
425 		if (!sdata) {
426 			skb->dev = NULL;
427 		} else if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
428 			ieee80211_mgd_conn_tx_status(sdata, hdr->frame_control,
429 						     acked);
430 		} else if (ieee80211_is_nullfunc(hdr->frame_control) ||
431 			   ieee80211_is_qos_nullfunc(hdr->frame_control)) {
432 			cfg80211_probe_status(sdata->dev, hdr->addr1,
433 					      cookie, acked, GFP_ATOMIC);
434 		} else {
435 			cfg80211_mgmt_tx_status(&sdata->wdev, cookie, skb->data,
436 						skb->len, acked, GFP_ATOMIC);
437 		}
438 
439 		rcu_read_unlock();
440 	}
441 
442 	if (unlikely(info->ack_frame_id)) {
443 		struct sk_buff *ack_skb;
444 		unsigned long flags;
445 
446 		spin_lock_irqsave(&local->ack_status_lock, flags);
447 		ack_skb = idr_find(&local->ack_status_frames,
448 				   info->ack_frame_id);
449 		if (ack_skb)
450 			idr_remove(&local->ack_status_frames,
451 				   info->ack_frame_id);
452 		spin_unlock_irqrestore(&local->ack_status_lock, flags);
453 
454 		if (ack_skb) {
455 			if (!dropped) {
456 				/* consumes ack_skb */
457 				skb_complete_wifi_ack(ack_skb, acked);
458 			} else {
459 				dev_kfree_skb_any(ack_skb);
460 			}
461 		}
462 	}
463 }
464 
465 /*
466  * Use a static threshold for now, best value to be determined
467  * by testing ...
468  * Should it depend on:
469  *  - on # of retransmissions
470  *  - current throughput (higher value for higher tpt)?
471  */
472 #define STA_LOST_PKT_THRESHOLD	50
473 
474 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
475 {
476 	struct sk_buff *skb2;
477 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
478 	struct ieee80211_local *local = hw_to_local(hw);
479 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
480 	__le16 fc;
481 	struct ieee80211_supported_band *sband;
482 	struct ieee80211_sub_if_data *sdata;
483 	struct net_device *prev_dev = NULL;
484 	struct sta_info *sta, *tmp;
485 	int retry_count = -1, i;
486 	int rates_idx = -1;
487 	bool send_to_cooked;
488 	bool acked;
489 	struct ieee80211_bar *bar;
490 	int rtap_len;
491 	int shift = 0;
492 
493 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
494 		if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
495 		    !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
496 			/* just the first aggr frame carry status info */
497 			info->status.rates[i].idx = -1;
498 			info->status.rates[i].count = 0;
499 			break;
500 		} else if (info->status.rates[i].idx < 0) {
501 			break;
502 		} else if (i >= hw->max_report_rates) {
503 			/* the HW cannot have attempted that rate */
504 			info->status.rates[i].idx = -1;
505 			info->status.rates[i].count = 0;
506 			break;
507 		}
508 
509 		retry_count += info->status.rates[i].count;
510 	}
511 	rates_idx = i - 1;
512 
513 	if (retry_count < 0)
514 		retry_count = 0;
515 
516 	rcu_read_lock();
517 
518 	sband = local->hw.wiphy->bands[info->band];
519 	fc = hdr->frame_control;
520 
521 	for_each_sta_info(local, hdr->addr1, sta, tmp) {
522 		/* skip wrong virtual interface */
523 		if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
524 			continue;
525 
526 		shift = ieee80211_vif_get_shift(&sta->sdata->vif);
527 
528 		if (info->flags & IEEE80211_TX_STATUS_EOSP)
529 			clear_sta_flag(sta, WLAN_STA_SP);
530 
531 		acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
532 		if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
533 			/*
534 			 * The STA is in power save mode, so assume
535 			 * that this TX packet failed because of that.
536 			 */
537 			ieee80211_handle_filtered_frame(local, sta, skb);
538 			rcu_read_unlock();
539 			return;
540 		}
541 
542 		/* mesh Peer Service Period support */
543 		if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
544 		    ieee80211_is_data_qos(fc))
545 			ieee80211_mpsp_trigger_process(
546 					ieee80211_get_qos_ctl(hdr),
547 					sta, true, acked);
548 
549 		if ((local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) &&
550 		    (rates_idx != -1))
551 			sta->last_tx_rate = info->status.rates[rates_idx];
552 
553 		if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
554 		    (ieee80211_is_data_qos(fc))) {
555 			u16 tid, ssn;
556 			u8 *qc;
557 
558 			qc = ieee80211_get_qos_ctl(hdr);
559 			tid = qc[0] & 0xf;
560 			ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
561 						& IEEE80211_SCTL_SEQ);
562 			ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
563 					   tid, ssn);
564 		}
565 
566 		if (!acked && ieee80211_is_back_req(fc)) {
567 			u16 tid, control;
568 
569 			/*
570 			 * BAR failed, store the last SSN and retry sending
571 			 * the BAR when the next unicast transmission on the
572 			 * same TID succeeds.
573 			 */
574 			bar = (struct ieee80211_bar *) skb->data;
575 			control = le16_to_cpu(bar->control);
576 			if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
577 				u16 ssn = le16_to_cpu(bar->start_seq_num);
578 
579 				tid = (control &
580 				       IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
581 				      IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
582 
583 				ieee80211_set_bar_pending(sta, tid, ssn);
584 			}
585 		}
586 
587 		if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
588 			ieee80211_handle_filtered_frame(local, sta, skb);
589 			rcu_read_unlock();
590 			return;
591 		} else {
592 			if (!acked)
593 				sta->tx_retry_failed++;
594 			sta->tx_retry_count += retry_count;
595 		}
596 
597 		rate_control_tx_status(local, sband, sta, skb);
598 		if (ieee80211_vif_is_mesh(&sta->sdata->vif))
599 			ieee80211s_update_metric(local, sta, skb);
600 
601 		if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
602 			ieee80211_frame_acked(sta, skb);
603 
604 		if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
605 		    (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS))
606 			ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data, acked);
607 
608 		if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) {
609 			if (info->flags & IEEE80211_TX_STAT_ACK) {
610 				if (sta->lost_packets)
611 					sta->lost_packets = 0;
612 			} else if (++sta->lost_packets >= STA_LOST_PKT_THRESHOLD) {
613 				cfg80211_cqm_pktloss_notify(sta->sdata->dev,
614 							    sta->sta.addr,
615 							    sta->lost_packets,
616 							    GFP_ATOMIC);
617 				sta->lost_packets = 0;
618 			}
619 		}
620 
621 		if (acked)
622 			sta->last_ack_signal = info->status.ack_signal;
623 	}
624 
625 	rcu_read_unlock();
626 
627 	ieee80211_led_tx(local);
628 
629 	/* SNMP counters
630 	 * Fragments are passed to low-level drivers as separate skbs, so these
631 	 * are actually fragments, not frames. Update frame counters only for
632 	 * the first fragment of the frame. */
633 	if (info->flags & IEEE80211_TX_STAT_ACK) {
634 		if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
635 			local->dot11TransmittedFrameCount++;
636 			if (is_multicast_ether_addr(hdr->addr1))
637 				local->dot11MulticastTransmittedFrameCount++;
638 			if (retry_count > 0)
639 				local->dot11RetryCount++;
640 			if (retry_count > 1)
641 				local->dot11MultipleRetryCount++;
642 		}
643 
644 		/* This counter shall be incremented for an acknowledged MPDU
645 		 * with an individual address in the address 1 field or an MPDU
646 		 * with a multicast address in the address 1 field of type Data
647 		 * or Management. */
648 		if (!is_multicast_ether_addr(hdr->addr1) ||
649 		    ieee80211_is_data(fc) ||
650 		    ieee80211_is_mgmt(fc))
651 			local->dot11TransmittedFragmentCount++;
652 	} else {
653 		if (ieee80211_is_first_frag(hdr->seq_ctrl))
654 			local->dot11FailedCount++;
655 	}
656 
657 	if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
658 	    (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) &&
659 	    !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
660 	    local->ps_sdata && !(local->scanning)) {
661 		if (info->flags & IEEE80211_TX_STAT_ACK) {
662 			local->ps_sdata->u.mgd.flags |=
663 					IEEE80211_STA_NULLFUNC_ACKED;
664 		} else
665 			mod_timer(&local->dynamic_ps_timer, jiffies +
666 					msecs_to_jiffies(10));
667 	}
668 
669 	ieee80211_report_used_skb(local, skb, false);
670 
671 	/* this was a transmitted frame, but now we want to reuse it */
672 	skb_orphan(skb);
673 
674 	/* Need to make a copy before skb->cb gets cleared */
675 	send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
676 			 !(ieee80211_is_data(fc));
677 
678 	/*
679 	 * This is a bit racy but we can avoid a lot of work
680 	 * with this test...
681 	 */
682 	if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
683 		dev_kfree_skb(skb);
684 		return;
685 	}
686 
687 	/* send frame to monitor interfaces now */
688 	rtap_len = ieee80211_tx_radiotap_len(info);
689 	if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
690 		pr_err("ieee80211_tx_status: headroom too small\n");
691 		dev_kfree_skb(skb);
692 		return;
693 	}
694 	ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
695 					 rtap_len, shift);
696 
697 	/* XXX: is this sufficient for BPF? */
698 	skb_set_mac_header(skb, 0);
699 	skb->ip_summed = CHECKSUM_UNNECESSARY;
700 	skb->pkt_type = PACKET_OTHERHOST;
701 	skb->protocol = htons(ETH_P_802_2);
702 	memset(skb->cb, 0, sizeof(skb->cb));
703 
704 	rcu_read_lock();
705 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
706 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
707 			if (!ieee80211_sdata_running(sdata))
708 				continue;
709 
710 			if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
711 			    !send_to_cooked)
712 				continue;
713 
714 			if (prev_dev) {
715 				skb2 = skb_clone(skb, GFP_ATOMIC);
716 				if (skb2) {
717 					skb2->dev = prev_dev;
718 					netif_rx(skb2);
719 				}
720 			}
721 
722 			prev_dev = sdata->dev;
723 		}
724 	}
725 	if (prev_dev) {
726 		skb->dev = prev_dev;
727 		netif_rx(skb);
728 		skb = NULL;
729 	}
730 	rcu_read_unlock();
731 	dev_kfree_skb(skb);
732 }
733 EXPORT_SYMBOL(ieee80211_tx_status);
734 
735 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
736 {
737 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
738 	cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
739 				    num_packets, GFP_ATOMIC);
740 }
741 EXPORT_SYMBOL(ieee80211_report_low_ack);
742 
743 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
744 {
745 	struct ieee80211_local *local = hw_to_local(hw);
746 
747 	ieee80211_report_used_skb(local, skb, true);
748 	dev_kfree_skb_any(skb);
749 }
750 EXPORT_SYMBOL(ieee80211_free_txskb);
751 
752 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
753 			      struct sk_buff_head *skbs)
754 {
755 	struct sk_buff *skb;
756 
757 	while ((skb = __skb_dequeue(skbs)))
758 		ieee80211_free_txskb(hw, skb);
759 }
760