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  *
   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 }