xref: /linux/net/mac80211/status.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
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  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/export.h>
14 #include <linux/etherdevice.h>
15 #include <net/mac80211.h>
16 #include <asm/unaligned.h>
17 #include "ieee80211_i.h"
18 #include "rate.h"
19 #include "mesh.h"
20 #include "led.h"
21 #include "wme.h"
22 
23 
24 void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
25 				 struct sk_buff *skb)
26 {
27 	struct ieee80211_local *local = hw_to_local(hw);
28 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
29 	int tmp;
30 
31 	skb->pkt_type = IEEE80211_TX_STATUS_MSG;
32 	skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
33 		       &local->skb_queue : &local->skb_queue_unreliable, skb);
34 	tmp = skb_queue_len(&local->skb_queue) +
35 		skb_queue_len(&local->skb_queue_unreliable);
36 	while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
37 	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
38 		ieee80211_free_txskb(hw, skb);
39 		tmp--;
40 		I802_DEBUG_INC(local->tx_status_drop);
41 	}
42 	tasklet_schedule(&local->tasklet);
43 }
44 EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
45 
46 static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
47 					    struct sta_info *sta,
48 					    struct sk_buff *skb)
49 {
50 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
51 	struct ieee80211_hdr *hdr = (void *)skb->data;
52 	int ac;
53 
54 	if (info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
55 			   IEEE80211_TX_CTL_AMPDU)) {
56 		ieee80211_free_txskb(&local->hw, skb);
57 		return;
58 	}
59 
60 	/*
61 	 * This skb 'survived' a round-trip through the driver, and
62 	 * hopefully the driver didn't mangle it too badly. However,
63 	 * we can definitely not rely on the control information
64 	 * being correct. Clear it so we don't get junk there, and
65 	 * indicate that it needs new processing, but must not be
66 	 * modified/encrypted again.
67 	 */
68 	memset(&info->control, 0, sizeof(info->control));
69 
70 	info->control.jiffies = jiffies;
71 	info->control.vif = &sta->sdata->vif;
72 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
73 		       IEEE80211_TX_INTFL_RETRANSMISSION;
74 	info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
75 
76 	sta->status_stats.filtered++;
77 
78 	/*
79 	 * Clear more-data bit on filtered frames, it might be set
80 	 * but later frames might time out so it might have to be
81 	 * clear again ... It's all rather unlikely (this frame
82 	 * should time out first, right?) but let's not confuse
83 	 * peers unnecessarily.
84 	 */
85 	if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
86 		hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);
87 
88 	if (ieee80211_is_data_qos(hdr->frame_control)) {
89 		u8 *p = ieee80211_get_qos_ctl(hdr);
90 		int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
91 
92 		/*
93 		 * Clear EOSP if set, this could happen e.g.
94 		 * if an absence period (us being a P2P GO)
95 		 * shortens the SP.
96 		 */
97 		if (*p & IEEE80211_QOS_CTL_EOSP)
98 			*p &= ~IEEE80211_QOS_CTL_EOSP;
99 		ac = ieee80211_ac_from_tid(tid);
100 	} else {
101 		ac = IEEE80211_AC_BE;
102 	}
103 
104 	/*
105 	 * Clear the TX filter mask for this STA when sending the next
106 	 * packet. If the STA went to power save mode, this will happen
107 	 * when it wakes up for the next time.
108 	 */
109 	set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
110 	ieee80211_clear_fast_xmit(sta);
111 
112 	/*
113 	 * This code races in the following way:
114 	 *
115 	 *  (1) STA sends frame indicating it will go to sleep and does so
116 	 *  (2) hardware/firmware adds STA to filter list, passes frame up
117 	 *  (3) hardware/firmware processes TX fifo and suppresses a frame
118 	 *  (4) we get TX status before having processed the frame and
119 	 *	knowing that the STA has gone to sleep.
120 	 *
121 	 * This is actually quite unlikely even when both those events are
122 	 * processed from interrupts coming in quickly after one another or
123 	 * even at the same time because we queue both TX status events and
124 	 * RX frames to be processed by a tasklet and process them in the
125 	 * same order that they were received or TX status last. Hence, there
126 	 * is no race as long as the frame RX is processed before the next TX
127 	 * status, which drivers can ensure, see below.
128 	 *
129 	 * Note that this can only happen if the hardware or firmware can
130 	 * actually add STAs to the filter list, if this is done by the
131 	 * driver in response to set_tim() (which will only reduce the race
132 	 * this whole filtering tries to solve, not completely solve it)
133 	 * this situation cannot happen.
134 	 *
135 	 * To completely solve this race drivers need to make sure that they
136 	 *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
137 	 *	functions and
138 	 *  (b) always process RX events before TX status events if ordering
139 	 *      can be unknown, for example with different interrupt status
140 	 *	bits.
141 	 *  (c) if PS mode transitions are manual (i.e. the flag
142 	 *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
143 	 *      changes before calling TX status events if ordering can be
144 	 *	unknown.
145 	 */
146 	if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
147 	    skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
148 		skb_queue_tail(&sta->tx_filtered[ac], skb);
149 		sta_info_recalc_tim(sta);
150 
151 		if (!timer_pending(&local->sta_cleanup))
152 			mod_timer(&local->sta_cleanup,
153 				  round_jiffies(jiffies +
154 						STA_INFO_CLEANUP_INTERVAL));
155 		return;
156 	}
157 
158 	if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
159 	    !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
160 		/* Software retry the packet once */
161 		info->flags |= IEEE80211_TX_INTFL_RETRIED;
162 		ieee80211_add_pending_skb(local, skb);
163 		return;
164 	}
165 
166 	ps_dbg_ratelimited(sta->sdata,
167 			   "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
168 			   skb_queue_len(&sta->tx_filtered[ac]),
169 			   !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);
170 	ieee80211_free_txskb(&local->hw, skb);
171 }
172 
173 static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
174 {
175 	struct tid_ampdu_tx *tid_tx;
176 
177 	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
178 	if (!tid_tx || !tid_tx->bar_pending)
179 		return;
180 
181 	tid_tx->bar_pending = false;
182 	ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);
183 }
184 
185 static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
186 {
187 	struct ieee80211_mgmt *mgmt = (void *) skb->data;
188 	struct ieee80211_local *local = sta->local;
189 	struct ieee80211_sub_if_data *sdata = sta->sdata;
190 
191 	if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
192 		sta->status_stats.last_ack = jiffies;
193 
194 	if (ieee80211_is_data_qos(mgmt->frame_control)) {
195 		struct ieee80211_hdr *hdr = (void *) skb->data;
196 		u8 *qc = ieee80211_get_qos_ctl(hdr);
197 		u16 tid = qc[0] & 0xf;
198 
199 		ieee80211_check_pending_bar(sta, hdr->addr1, tid);
200 	}
201 
202 	if (ieee80211_is_action(mgmt->frame_control) &&
203 	    !ieee80211_has_protected(mgmt->frame_control) &&
204 	    mgmt->u.action.category == WLAN_CATEGORY_HT &&
205 	    mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
206 	    ieee80211_sdata_running(sdata)) {
207 		enum ieee80211_smps_mode smps_mode;
208 
209 		switch (mgmt->u.action.u.ht_smps.smps_control) {
210 		case WLAN_HT_SMPS_CONTROL_DYNAMIC:
211 			smps_mode = IEEE80211_SMPS_DYNAMIC;
212 			break;
213 		case WLAN_HT_SMPS_CONTROL_STATIC:
214 			smps_mode = IEEE80211_SMPS_STATIC;
215 			break;
216 		case WLAN_HT_SMPS_CONTROL_DISABLED:
217 		default: /* shouldn't happen since we don't send that */
218 			smps_mode = IEEE80211_SMPS_OFF;
219 			break;
220 		}
221 
222 		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
223 			/*
224 			 * This update looks racy, but isn't -- if we come
225 			 * here we've definitely got a station that we're
226 			 * talking to, and on a managed interface that can
227 			 * only be the AP. And the only other place updating
228 			 * this variable in managed mode is before association.
229 			 */
230 			sdata->smps_mode = smps_mode;
231 			ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
232 		} else if (sdata->vif.type == NL80211_IFTYPE_AP ||
233 			   sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
234 			sta->known_smps_mode = smps_mode;
235 		}
236 	}
237 }
238 
239 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
240 {
241 	struct tid_ampdu_tx *tid_tx;
242 
243 	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
244 	if (!tid_tx)
245 		return;
246 
247 	tid_tx->failed_bar_ssn = ssn;
248 	tid_tx->bar_pending = true;
249 }
250 
251 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
252 {
253 	int len = sizeof(struct ieee80211_radiotap_header);
254 
255 	/* IEEE80211_RADIOTAP_RATE rate */
256 	if (info->status.rates[0].idx >= 0 &&
257 	    !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
258 					     IEEE80211_TX_RC_VHT_MCS)))
259 		len += 2;
260 
261 	/* IEEE80211_RADIOTAP_TX_FLAGS */
262 	len += 2;
263 
264 	/* IEEE80211_RADIOTAP_DATA_RETRIES */
265 	len += 1;
266 
267 	/* IEEE80211_RADIOTAP_MCS
268 	 * IEEE80211_RADIOTAP_VHT */
269 	if (info->status.rates[0].idx >= 0) {
270 		if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
271 			len += 3;
272 		else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
273 			len = ALIGN(len, 2) + 12;
274 	}
275 
276 	return len;
277 }
278 
279 static void
280 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
281 				 struct ieee80211_supported_band *sband,
282 				 struct sk_buff *skb, int retry_count,
283 				 int rtap_len, int shift)
284 {
285 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
286 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
287 	struct ieee80211_radiotap_header *rthdr;
288 	unsigned char *pos;
289 	u16 txflags;
290 
291 	rthdr = skb_push(skb, rtap_len);
292 
293 	memset(rthdr, 0, rtap_len);
294 	rthdr->it_len = cpu_to_le16(rtap_len);
295 	rthdr->it_present =
296 		cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
297 			    (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
298 	pos = (unsigned char *)(rthdr + 1);
299 
300 	/*
301 	 * XXX: Once radiotap gets the bitmap reset thing the vendor
302 	 *	extensions proposal contains, we can actually report
303 	 *	the whole set of tries we did.
304 	 */
305 
306 	/* IEEE80211_RADIOTAP_RATE */
307 	if (info->status.rates[0].idx >= 0 &&
308 	    !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
309 					     IEEE80211_TX_RC_VHT_MCS))) {
310 		u16 rate;
311 
312 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
313 		rate = sband->bitrates[info->status.rates[0].idx].bitrate;
314 		*pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
315 		/* padding for tx flags */
316 		pos += 2;
317 	}
318 
319 	/* IEEE80211_RADIOTAP_TX_FLAGS */
320 	txflags = 0;
321 	if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
322 	    !is_multicast_ether_addr(hdr->addr1))
323 		txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
324 
325 	if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
326 		txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
327 	if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
328 		txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
329 
330 	put_unaligned_le16(txflags, pos);
331 	pos += 2;
332 
333 	/* IEEE80211_RADIOTAP_DATA_RETRIES */
334 	/* for now report the total retry_count */
335 	*pos = retry_count;
336 	pos++;
337 
338 	if (info->status.rates[0].idx < 0)
339 		return;
340 
341 	/* IEEE80211_RADIOTAP_MCS
342 	 * IEEE80211_RADIOTAP_VHT */
343 	if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
344 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
345 		pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
346 			 IEEE80211_RADIOTAP_MCS_HAVE_GI |
347 			 IEEE80211_RADIOTAP_MCS_HAVE_BW;
348 		if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
349 			pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
350 		if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
351 			pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
352 		if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
353 			pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
354 		pos[2] = info->status.rates[0].idx;
355 		pos += 3;
356 	} else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
357 		u16 known = local->hw.radiotap_vht_details &
358 			(IEEE80211_RADIOTAP_VHT_KNOWN_GI |
359 			 IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
360 
361 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
362 
363 		/* required alignment from rthdr */
364 		pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
365 
366 		/* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
367 		put_unaligned_le16(known, pos);
368 		pos += 2;
369 
370 		/* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
371 		if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
372 			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
373 		pos++;
374 
375 		/* u8 bandwidth */
376 		if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
377 			*pos = 1;
378 		else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
379 			*pos = 4;
380 		else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
381 			*pos = 11;
382 		else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
383 			*pos = 0;
384 		pos++;
385 
386 		/* u8 mcs_nss[4] */
387 		*pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
388 			ieee80211_rate_get_vht_nss(&info->status.rates[0]);
389 		pos += 4;
390 
391 		/* u8 coding */
392 		pos++;
393 		/* u8 group_id */
394 		pos++;
395 		/* u16 partial_aid */
396 		pos += 2;
397 	}
398 }
399 
400 /*
401  * Handles the tx for TDLS teardown frames.
402  * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
403  */
404 static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
405 					struct ieee80211_sub_if_data *sdata,
406 					struct sk_buff *skb, u32 flags)
407 {
408 	struct sk_buff *teardown_skb;
409 	struct sk_buff *orig_teardown_skb;
410 	bool is_teardown = false;
411 
412 	/* Get the teardown data we need and free the lock */
413 	spin_lock(&sdata->u.mgd.teardown_lock);
414 	teardown_skb = sdata->u.mgd.teardown_skb;
415 	orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
416 	if ((skb == orig_teardown_skb) && teardown_skb) {
417 		sdata->u.mgd.teardown_skb = NULL;
418 		sdata->u.mgd.orig_teardown_skb = NULL;
419 		is_teardown = true;
420 	}
421 	spin_unlock(&sdata->u.mgd.teardown_lock);
422 
423 	if (is_teardown) {
424 		/* This mechanism relies on being able to get ACKs */
425 		WARN_ON(!ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS));
426 
427 		/* Check if peer has ACKed */
428 		if (flags & IEEE80211_TX_STAT_ACK) {
429 			dev_kfree_skb_any(teardown_skb);
430 		} else {
431 			tdls_dbg(sdata,
432 				 "TDLS Resending teardown through AP\n");
433 
434 			ieee80211_subif_start_xmit(teardown_skb, skb->dev);
435 		}
436 	}
437 }
438 
439 static struct ieee80211_sub_if_data *
440 ieee80211_sdata_from_skb(struct ieee80211_local *local, struct sk_buff *skb)
441 {
442 	struct ieee80211_sub_if_data *sdata;
443 
444 	if (skb->dev) {
445 		list_for_each_entry_rcu(sdata, &local->interfaces, list) {
446 			if (!sdata->dev)
447 				continue;
448 
449 			if (skb->dev == sdata->dev)
450 				return sdata;
451 		}
452 
453 		return NULL;
454 	}
455 
456 	return rcu_dereference(local->p2p_sdata);
457 }
458 
459 static void ieee80211_report_ack_skb(struct ieee80211_local *local,
460 				     struct ieee80211_tx_info *info,
461 				     bool acked, bool dropped)
462 {
463 	struct sk_buff *skb;
464 	unsigned long flags;
465 
466 	spin_lock_irqsave(&local->ack_status_lock, flags);
467 	skb = idr_remove(&local->ack_status_frames, info->ack_frame_id);
468 	spin_unlock_irqrestore(&local->ack_status_lock, flags);
469 
470 	if (!skb)
471 		return;
472 
473 	if (dropped) {
474 		dev_kfree_skb_any(skb);
475 		return;
476 	}
477 
478 	if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {
479 		u64 cookie = IEEE80211_SKB_CB(skb)->ack.cookie;
480 		struct ieee80211_sub_if_data *sdata;
481 		struct ieee80211_hdr *hdr = (void *)skb->data;
482 
483 		rcu_read_lock();
484 		sdata = ieee80211_sdata_from_skb(local, skb);
485 		if (sdata) {
486 			if (ieee80211_is_nullfunc(hdr->frame_control) ||
487 			    ieee80211_is_qos_nullfunc(hdr->frame_control))
488 				cfg80211_probe_status(sdata->dev, hdr->addr1,
489 						      cookie, acked,
490 						      GFP_ATOMIC);
491 			else
492 				cfg80211_mgmt_tx_status(&sdata->wdev, cookie,
493 							skb->data, skb->len,
494 							acked, GFP_ATOMIC);
495 		}
496 		rcu_read_unlock();
497 
498 		dev_kfree_skb_any(skb);
499 	} else {
500 		/* consumes skb */
501 		skb_complete_wifi_ack(skb, acked);
502 	}
503 }
504 
505 static void ieee80211_report_used_skb(struct ieee80211_local *local,
506 				      struct sk_buff *skb, bool dropped)
507 {
508 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
509 	struct ieee80211_hdr *hdr = (void *)skb->data;
510 	bool acked = info->flags & IEEE80211_TX_STAT_ACK;
511 
512 	if (dropped)
513 		acked = false;
514 
515 	if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
516 		struct ieee80211_sub_if_data *sdata;
517 
518 		rcu_read_lock();
519 
520 		sdata = ieee80211_sdata_from_skb(local, skb);
521 
522 		if (!sdata) {
523 			skb->dev = NULL;
524 		} else {
525 			unsigned int hdr_size =
526 				ieee80211_hdrlen(hdr->frame_control);
527 
528 			/* Check to see if packet is a TDLS teardown packet */
529 			if (ieee80211_is_data(hdr->frame_control) &&
530 			    (ieee80211_get_tdls_action(skb, hdr_size) ==
531 			     WLAN_TDLS_TEARDOWN))
532 				ieee80211_tdls_td_tx_handle(local, sdata, skb,
533 							    info->flags);
534 			else
535 				ieee80211_mgd_conn_tx_status(sdata,
536 							     hdr->frame_control,
537 							     acked);
538 		}
539 
540 		rcu_read_unlock();
541 	} else if (info->ack_frame_id) {
542 		ieee80211_report_ack_skb(local, info, acked, dropped);
543 	}
544 
545 	if (!dropped && skb->destructor) {
546 		skb->wifi_acked_valid = 1;
547 		skb->wifi_acked = acked;
548 	}
549 
550 	ieee80211_led_tx(local);
551 }
552 
553 /*
554  * Use a static threshold for now, best value to be determined
555  * by testing ...
556  * Should it depend on:
557  *  - on # of retransmissions
558  *  - current throughput (higher value for higher tpt)?
559  */
560 #define STA_LOST_PKT_THRESHOLD	50
561 #define STA_LOST_TDLS_PKT_THRESHOLD	10
562 #define STA_LOST_TDLS_PKT_TIME		(10*HZ) /* 10secs since last ACK */
563 
564 static void ieee80211_lost_packet(struct sta_info *sta,
565 				  struct ieee80211_tx_info *info)
566 {
567 	/* If driver relies on its own algorithm for station kickout, skip
568 	 * mac80211 packet loss mechanism.
569 	 */
570 	if (ieee80211_hw_check(&sta->local->hw, REPORTS_LOW_ACK))
571 		return;
572 
573 	/* This packet was aggregated but doesn't carry status info */
574 	if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
575 	    !(info->flags & IEEE80211_TX_STAT_AMPDU))
576 		return;
577 
578 	sta->status_stats.lost_packets++;
579 	if (!sta->sta.tdls &&
580 	    sta->status_stats.lost_packets < STA_LOST_PKT_THRESHOLD)
581 		return;
582 
583 	/*
584 	 * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
585 	 * of the last packets were lost, and that no ACK was received in the
586 	 * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
587 	 * mechanism.
588 	 */
589 	if (sta->sta.tdls &&
590 	    (sta->status_stats.lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||
591 	     time_before(jiffies,
592 			 sta->status_stats.last_tdls_pkt_time +
593 			 STA_LOST_TDLS_PKT_TIME)))
594 		return;
595 
596 	cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
597 				    sta->status_stats.lost_packets, GFP_ATOMIC);
598 	sta->status_stats.lost_packets = 0;
599 }
600 
601 static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
602 				  struct ieee80211_tx_info *info,
603 				  int *retry_count)
604 {
605 	int rates_idx = -1;
606 	int count = -1;
607 	int i;
608 
609 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
610 		if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
611 		    !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
612 			/* just the first aggr frame carry status info */
613 			info->status.rates[i].idx = -1;
614 			info->status.rates[i].count = 0;
615 			break;
616 		} else if (info->status.rates[i].idx < 0) {
617 			break;
618 		} else if (i >= hw->max_report_rates) {
619 			/* the HW cannot have attempted that rate */
620 			info->status.rates[i].idx = -1;
621 			info->status.rates[i].count = 0;
622 			break;
623 		}
624 
625 		count += info->status.rates[i].count;
626 	}
627 	rates_idx = i - 1;
628 
629 	if (count < 0)
630 		count = 0;
631 
632 	*retry_count = count;
633 	return rates_idx;
634 }
635 
636 void ieee80211_tx_monitor(struct ieee80211_local *local, struct sk_buff *skb,
637 			  struct ieee80211_supported_band *sband,
638 			  int retry_count, int shift, bool send_to_cooked)
639 {
640 	struct sk_buff *skb2;
641 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
642 	struct ieee80211_sub_if_data *sdata;
643 	struct net_device *prev_dev = NULL;
644 	int rtap_len;
645 
646 	/* send frame to monitor interfaces now */
647 	rtap_len = ieee80211_tx_radiotap_len(info);
648 	if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
649 		pr_err("ieee80211_tx_status: headroom too small\n");
650 		dev_kfree_skb(skb);
651 		return;
652 	}
653 	ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
654 					 rtap_len, shift);
655 
656 	/* XXX: is this sufficient for BPF? */
657 	skb_reset_mac_header(skb);
658 	skb->ip_summed = CHECKSUM_UNNECESSARY;
659 	skb->pkt_type = PACKET_OTHERHOST;
660 	skb->protocol = htons(ETH_P_802_2);
661 	memset(skb->cb, 0, sizeof(skb->cb));
662 
663 	rcu_read_lock();
664 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
665 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
666 			if (!ieee80211_sdata_running(sdata))
667 				continue;
668 
669 			if ((sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES) &&
670 			    !send_to_cooked)
671 				continue;
672 
673 			if (prev_dev) {
674 				skb2 = skb_clone(skb, GFP_ATOMIC);
675 				if (skb2) {
676 					skb2->dev = prev_dev;
677 					netif_rx(skb2);
678 				}
679 			}
680 
681 			prev_dev = sdata->dev;
682 		}
683 	}
684 	if (prev_dev) {
685 		skb->dev = prev_dev;
686 		netif_rx(skb);
687 		skb = NULL;
688 	}
689 	rcu_read_unlock();
690 	dev_kfree_skb(skb);
691 }
692 
693 static void __ieee80211_tx_status(struct ieee80211_hw *hw,
694 				  struct ieee80211_tx_status *status)
695 {
696 	struct sk_buff *skb = status->skb;
697 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
698 	struct ieee80211_local *local = hw_to_local(hw);
699 	struct ieee80211_tx_info *info = status->info;
700 	struct sta_info *sta;
701 	__le16 fc;
702 	struct ieee80211_supported_band *sband;
703 	int retry_count;
704 	int rates_idx;
705 	bool send_to_cooked;
706 	bool acked;
707 	struct ieee80211_bar *bar;
708 	int shift = 0;
709 	int tid = IEEE80211_NUM_TIDS;
710 
711 	rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
712 
713 	sband = local->hw.wiphy->bands[info->band];
714 	fc = hdr->frame_control;
715 
716 	if (status->sta) {
717 		sta = container_of(status->sta, struct sta_info, sta);
718 		shift = ieee80211_vif_get_shift(&sta->sdata->vif);
719 
720 		if (info->flags & IEEE80211_TX_STATUS_EOSP)
721 			clear_sta_flag(sta, WLAN_STA_SP);
722 
723 		acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
724 
725 		/* mesh Peer Service Period support */
726 		if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
727 		    ieee80211_is_data_qos(fc))
728 			ieee80211_mpsp_trigger_process(
729 				ieee80211_get_qos_ctl(hdr), sta, true, acked);
730 
731 		if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
732 			/*
733 			 * The STA is in power save mode, so assume
734 			 * that this TX packet failed because of that.
735 			 */
736 			ieee80211_handle_filtered_frame(local, sta, skb);
737 			return;
738 		}
739 
740 		if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL) &&
741 		    (ieee80211_is_data(hdr->frame_control)) &&
742 		    (rates_idx != -1))
743 			sta->tx_stats.last_rate =
744 				info->status.rates[rates_idx];
745 
746 		if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
747 		    (ieee80211_is_data_qos(fc))) {
748 			u16 ssn;
749 			u8 *qc;
750 
751 			qc = ieee80211_get_qos_ctl(hdr);
752 			tid = qc[0] & 0xf;
753 			ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
754 						& IEEE80211_SCTL_SEQ);
755 			ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
756 					   tid, ssn);
757 		} else if (ieee80211_is_data_qos(fc)) {
758 			u8 *qc = ieee80211_get_qos_ctl(hdr);
759 
760 			tid = qc[0] & 0xf;
761 		}
762 
763 		if (!acked && ieee80211_is_back_req(fc)) {
764 			u16 control;
765 
766 			/*
767 			 * BAR failed, store the last SSN and retry sending
768 			 * the BAR when the next unicast transmission on the
769 			 * same TID succeeds.
770 			 */
771 			bar = (struct ieee80211_bar *) skb->data;
772 			control = le16_to_cpu(bar->control);
773 			if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
774 				u16 ssn = le16_to_cpu(bar->start_seq_num);
775 
776 				tid = (control &
777 				       IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
778 				      IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
779 
780 				ieee80211_set_bar_pending(sta, tid, ssn);
781 			}
782 		}
783 
784 		if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
785 			ieee80211_handle_filtered_frame(local, sta, skb);
786 			return;
787 		} else {
788 			if (!acked)
789 				sta->status_stats.retry_failed++;
790 			sta->status_stats.retry_count += retry_count;
791 
792 			if (ieee80211_is_data_present(fc)) {
793 				if (!acked)
794 					sta->status_stats.msdu_failed[tid]++;
795 
796 				sta->status_stats.msdu_retries[tid] +=
797 					retry_count;
798 			}
799 		}
800 
801 		rate_control_tx_status(local, sband, status);
802 		if (ieee80211_vif_is_mesh(&sta->sdata->vif))
803 			ieee80211s_update_metric(local, sta, skb);
804 
805 		if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
806 			ieee80211_frame_acked(sta, skb);
807 
808 		if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
809 		    ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
810 			ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
811 						acked, info->status.tx_time);
812 
813 		if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
814 			if (info->flags & IEEE80211_TX_STAT_ACK) {
815 				if (sta->status_stats.lost_packets)
816 					sta->status_stats.lost_packets = 0;
817 
818 				/* Track when last TDLS packet was ACKed */
819 				if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
820 					sta->status_stats.last_tdls_pkt_time =
821 						jiffies;
822 			} else {
823 				ieee80211_lost_packet(sta, info);
824 			}
825 		}
826 	}
827 
828 	/* SNMP counters
829 	 * Fragments are passed to low-level drivers as separate skbs, so these
830 	 * are actually fragments, not frames. Update frame counters only for
831 	 * the first fragment of the frame. */
832 	if ((info->flags & IEEE80211_TX_STAT_ACK) ||
833 	    (info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED)) {
834 		if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
835 			I802_DEBUG_INC(local->dot11TransmittedFrameCount);
836 			if (is_multicast_ether_addr(ieee80211_get_DA(hdr)))
837 				I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
838 			if (retry_count > 0)
839 				I802_DEBUG_INC(local->dot11RetryCount);
840 			if (retry_count > 1)
841 				I802_DEBUG_INC(local->dot11MultipleRetryCount);
842 		}
843 
844 		/* This counter shall be incremented for an acknowledged MPDU
845 		 * with an individual address in the address 1 field or an MPDU
846 		 * with a multicast address in the address 1 field of type Data
847 		 * or Management. */
848 		if (!is_multicast_ether_addr(hdr->addr1) ||
849 		    ieee80211_is_data(fc) ||
850 		    ieee80211_is_mgmt(fc))
851 			I802_DEBUG_INC(local->dot11TransmittedFragmentCount);
852 	} else {
853 		if (ieee80211_is_first_frag(hdr->seq_ctrl))
854 			I802_DEBUG_INC(local->dot11FailedCount);
855 	}
856 
857 	if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
858 	    ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS) &&
859 	    !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
860 	    local->ps_sdata && !(local->scanning)) {
861 		if (info->flags & IEEE80211_TX_STAT_ACK) {
862 			local->ps_sdata->u.mgd.flags |=
863 					IEEE80211_STA_NULLFUNC_ACKED;
864 		} else
865 			mod_timer(&local->dynamic_ps_timer, jiffies +
866 					msecs_to_jiffies(10));
867 	}
868 
869 	ieee80211_report_used_skb(local, skb, false);
870 
871 	/* this was a transmitted frame, but now we want to reuse it */
872 	skb_orphan(skb);
873 
874 	/* Need to make a copy before skb->cb gets cleared */
875 	send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
876 			 !(ieee80211_is_data(fc));
877 
878 	/*
879 	 * This is a bit racy but we can avoid a lot of work
880 	 * with this test...
881 	 */
882 	if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
883 		dev_kfree_skb(skb);
884 		return;
885 	}
886 
887 	/* send to monitor interfaces */
888 	ieee80211_tx_monitor(local, skb, sband, retry_count, shift, send_to_cooked);
889 }
890 
891 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
892 {
893 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
894 	struct ieee80211_local *local = hw_to_local(hw);
895 	struct ieee80211_tx_status status = {
896 		.skb = skb,
897 		.info = IEEE80211_SKB_CB(skb),
898 	};
899 	struct rhlist_head *tmp;
900 	struct sta_info *sta;
901 
902 	rcu_read_lock();
903 
904 	for_each_sta_info(local, hdr->addr1, sta, tmp) {
905 		/* skip wrong virtual interface */
906 		if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
907 			continue;
908 
909 		status.sta = &sta->sta;
910 		break;
911 	}
912 
913 	__ieee80211_tx_status(hw, &status);
914 	rcu_read_unlock();
915 }
916 EXPORT_SYMBOL(ieee80211_tx_status);
917 
918 void ieee80211_tx_status_ext(struct ieee80211_hw *hw,
919 			     struct ieee80211_tx_status *status)
920 {
921 	struct ieee80211_local *local = hw_to_local(hw);
922 	struct ieee80211_tx_info *info = status->info;
923 	struct ieee80211_sta *pubsta = status->sta;
924 	struct ieee80211_supported_band *sband;
925 	int retry_count;
926 	bool acked, noack_success;
927 
928 	if (status->skb)
929 		return __ieee80211_tx_status(hw, status);
930 
931 	if (!status->sta)
932 		return;
933 
934 	ieee80211_tx_get_rates(hw, info, &retry_count);
935 
936 	sband = hw->wiphy->bands[info->band];
937 
938 	acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
939 	noack_success = !!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED);
940 
941 	if (pubsta) {
942 		struct sta_info *sta;
943 
944 		sta = container_of(pubsta, struct sta_info, sta);
945 
946 		if (!acked)
947 			sta->status_stats.retry_failed++;
948 		sta->status_stats.retry_count += retry_count;
949 
950 		if (acked) {
951 			sta->status_stats.last_ack = jiffies;
952 
953 			if (sta->status_stats.lost_packets)
954 				sta->status_stats.lost_packets = 0;
955 
956 			/* Track when last TDLS packet was ACKed */
957 			if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
958 				sta->status_stats.last_tdls_pkt_time = jiffies;
959 		} else {
960 			ieee80211_lost_packet(sta, info);
961 		}
962 
963 		rate_control_tx_status(local, sband, status);
964 	}
965 
966 	if (acked || noack_success) {
967 		I802_DEBUG_INC(local->dot11TransmittedFrameCount);
968 		if (!pubsta)
969 			I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
970 		if (retry_count > 0)
971 			I802_DEBUG_INC(local->dot11RetryCount);
972 		if (retry_count > 1)
973 			I802_DEBUG_INC(local->dot11MultipleRetryCount);
974 	} else {
975 		I802_DEBUG_INC(local->dot11FailedCount);
976 	}
977 }
978 EXPORT_SYMBOL(ieee80211_tx_status_ext);
979 
980 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
981 {
982 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
983 	cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
984 				    num_packets, GFP_ATOMIC);
985 }
986 EXPORT_SYMBOL(ieee80211_report_low_ack);
987 
988 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
989 {
990 	struct ieee80211_local *local = hw_to_local(hw);
991 
992 	ieee80211_report_used_skb(local, skb, true);
993 	dev_kfree_skb_any(skb);
994 }
995 EXPORT_SYMBOL(ieee80211_free_txskb);
996 
997 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
998 			      struct sk_buff_head *skbs)
999 {
1000 	struct sk_buff *skb;
1001 
1002 	while ((skb = __skb_dequeue(skbs)))
1003 		ieee80211_free_txskb(hw, skb);
1004 }
1005