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[karo-tx-linux.git] / net / mac80211 / status.c
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 }