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         struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
 191
 192         if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
 193                 sta->status_stats.last_ack = jiffies;
 194                 if (txinfo->status.is_valid_ack_signal) {
 195                         sta->status_stats.last_ack_signal =
 196                                          (s8)txinfo->status.ack_signal;
 197                         sta->status_stats.ack_signal_filled = true;
 198                         ewma_avg_signal_add(&sta->status_stats.avg_ack_signal,
 199                                             -txinfo->status.ack_signal);
 200                 }
 201         }
 202
 203         if (ieee80211_is_data_qos(mgmt->frame_control)) {
 204                 struct ieee80211_hdr *hdr = (void *) skb->data;
 205                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 206                 u16 tid = qc[0] & 0xf;
 207
 208                 ieee80211_check_pending_bar(sta, hdr->addr1, tid);
 209         }
 210
 211         if (ieee80211_is_action(mgmt->frame_control) &&
 212             !ieee80211_has_protected(mgmt->frame_control) &&
 213             mgmt->u.action.category == WLAN_CATEGORY_HT &&
 214             mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
 215             ieee80211_sdata_running(sdata)) {
 216                 enum ieee80211_smps_mode smps_mode;
 217
 218                 switch (mgmt->u.action.u.ht_smps.smps_control) {
 219                 case WLAN_HT_SMPS_CONTROL_DYNAMIC:
 220                         smps_mode = IEEE80211_SMPS_DYNAMIC;
 221                         break;
 222                 case WLAN_HT_SMPS_CONTROL_STATIC:
 223                         smps_mode = IEEE80211_SMPS_STATIC;
 224                         break;
 225                 case WLAN_HT_SMPS_CONTROL_DISABLED:
 226                 default: /* shouldn't happen since we don't send that */
 227                         smps_mode = IEEE80211_SMPS_OFF;
 228                         break;
 229                 }
 230
 231                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 232                         /*
 233                          * This update looks racy, but isn't -- if we come
 234                          * here we've definitely got a station that we're
 235                          * talking to, and on a managed interface that can
 236                          * only be the AP. And the only other place updating
 237                          * this variable in managed mode is before association.
 238                          */
 239                         sdata->smps_mode = smps_mode;
 240                         ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
 241                 } else if (sdata->vif.type == NL80211_IFTYPE_AP ||
 242                            sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 243                         sta->known_smps_mode = smps_mode;
 244                 }
 245         }
 246 }
 247
 248 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
 249 {
 250         struct tid_ampdu_tx *tid_tx;
 251
 252         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 253         if (!tid_tx)
 254                 return;
 255
 256         tid_tx->failed_bar_ssn = ssn;
 257         tid_tx->bar_pending = true;
 258 }
 259
 260 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
 261 {
 262         int len = sizeof(struct ieee80211_radiotap_header);
 263
 264         /* IEEE80211_RADIOTAP_RATE rate */
 265         if (info->status.rates[0].idx >= 0 &&
 266             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 267                                              IEEE80211_TX_RC_VHT_MCS)))
 268                 len += 2;
 269
 270         /* IEEE80211_RADIOTAP_TX_FLAGS */
 271         len += 2;
 272
 273         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 274         len += 1;
 275
 276         /* IEEE80211_RADIOTAP_MCS
 277          * IEEE80211_RADIOTAP_VHT */
 278         if (info->status.rates[0].idx >= 0) {
 279                 if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
 280                         len += 3;
 281                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
 282                         len = ALIGN(len, 2) + 12;
 283         }
 284
 285         return len;
 286 }
 287
 288 static void
 289 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
 290                                  struct ieee80211_supported_band *sband,
 291                                  struct sk_buff *skb, int retry_count,
 292                                  int rtap_len, int shift)
 293 {
 294         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 295         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 296         struct ieee80211_radiotap_header *rthdr;
 297         unsigned char *pos;
 298         u16 txflags;
 299
 300         rthdr = skb_push(skb, rtap_len);
 301
 302         memset(rthdr, 0, rtap_len);
 303         rthdr->it_len = cpu_to_le16(rtap_len);
 304         rthdr->it_present =
 305                 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
 306                             (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
 307         pos = (unsigned char *)(rthdr + 1);
 308
 309         /*
 310          * XXX: Once radiotap gets the bitmap reset thing the vendor
 311          *      extensions proposal contains, we can actually report
 312          *      the whole set of tries we did.
 313          */
 314
 315         /* IEEE80211_RADIOTAP_RATE */
 316         if (info->status.rates[0].idx >= 0 &&
 317             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 318                                              IEEE80211_TX_RC_VHT_MCS))) {
 319                 u16 rate;
 320
 321                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 322                 rate = sband->bitrates[info->status.rates[0].idx].bitrate;
 323                 *pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
 324                 /* padding for tx flags */
 325                 pos += 2;
 326         }
 327
 328         /* IEEE80211_RADIOTAP_TX_FLAGS */
 329         txflags = 0;
 330         if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
 331             !is_multicast_ether_addr(hdr->addr1))
 332                 txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
 333
 334         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
 335                 txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
 336         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
 337                 txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
 338
 339         put_unaligned_le16(txflags, pos);
 340         pos += 2;
 341
 342         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 343         /* for now report the total retry_count */
 344         *pos = retry_count;
 345         pos++;
 346
 347         if (info->status.rates[0].idx < 0)
 348                 return;
 349
 350         /* IEEE80211_RADIOTAP_MCS
 351          * IEEE80211_RADIOTAP_VHT */
 352         if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
 353                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 354                 pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
 355                          IEEE80211_RADIOTAP_MCS_HAVE_GI |
 356                          IEEE80211_RADIOTAP_MCS_HAVE_BW;
 357                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 358                         pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
 359                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 360                         pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
 361                 if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
 362                         pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 363                 pos[2] = info->status.rates[0].idx;
 364                 pos += 3;
 365         } else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
 366                 u16 known = local->hw.radiotap_vht_details &
 367                         (IEEE80211_RADIOTAP_VHT_KNOWN_GI |
 368                          IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
 369
 370                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 371
 372                 /* required alignment from rthdr */
 373                 pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
 374
 375                 /* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
 376                 put_unaligned_le16(known, pos);
 377                 pos += 2;
 378
 379                 /* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
 380                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 381                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 382                 pos++;
 383
 384                 /* u8 bandwidth */
 385                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 386                         *pos = 1;
 387                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
 388                         *pos = 4;
 389                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
 390                         *pos = 11;
 391                 else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
 392                         *pos = 0;
 393                 pos++;
 394
 395                 /* u8 mcs_nss[4] */
 396                 *pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
 397                         ieee80211_rate_get_vht_nss(&info->status.rates[0]);
 398                 pos += 4;
 399
 400                 /* u8 coding */
 401                 pos++;
 402                 /* u8 group_id */
 403                 pos++;
 404                 /* u16 partial_aid */
 405                 pos += 2;
 406         }
 407 }
 408
 409 /*
 410  * Handles the tx for TDLS teardown frames.
 411  * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
 412  */
 413 static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
 414                                         struct ieee80211_sub_if_data *sdata,
 415                                         struct sk_buff *skb, u32 flags)
 416 {
 417         struct sk_buff *teardown_skb;
 418         struct sk_buff *orig_teardown_skb;
 419         bool is_teardown = false;
 420
 421         /* Get the teardown data we need and free the lock */
 422         spin_lock(&sdata->u.mgd.teardown_lock);
 423         teardown_skb = sdata->u.mgd.teardown_skb;
 424         orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
 425         if ((skb == orig_teardown_skb) && teardown_skb) {
 426                 sdata->u.mgd.teardown_skb = NULL;
 427                 sdata->u.mgd.orig_teardown_skb = NULL;
 428                 is_teardown = true;
 429         }
 430         spin_unlock(&sdata->u.mgd.teardown_lock);
 431
 432         if (is_teardown) {
 433                 /* This mechanism relies on being able to get ACKs */
 434                 WARN_ON(!ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS));
 435
 436                 /* Check if peer has ACKed */
 437                 if (flags & IEEE80211_TX_STAT_ACK) {
 438                         dev_kfree_skb_any(teardown_skb);
 439                 } else {
 440                         tdls_dbg(sdata,
 441                                  "TDLS Resending teardown through AP\n");
 442
 443                         ieee80211_subif_start_xmit(teardown_skb, skb->dev);
 444                 }
 445         }
 446 }
 447
 448 static struct ieee80211_sub_if_data *
 449 ieee80211_sdata_from_skb(struct ieee80211_local *local, struct sk_buff *skb)
 450 {
 451         struct ieee80211_sub_if_data *sdata;
 452
 453         if (skb->dev) {
 454                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 455                         if (!sdata->dev)
 456                                 continue;
 457
 458                         if (skb->dev == sdata->dev)
 459                                 return sdata;
 460                 }
 461
 462                 return NULL;
 463         }
 464
 465         return rcu_dereference(local->p2p_sdata);
 466 }
 467
 468 static void ieee80211_report_ack_skb(struct ieee80211_local *local,
 469                                      struct ieee80211_tx_info *info,
 470                                      bool acked, bool dropped)
 471 {
 472         struct sk_buff *skb;
 473         unsigned long flags;
 474
 475         spin_lock_irqsave(&local->ack_status_lock, flags);
 476         skb = idr_remove(&local->ack_status_frames, info->ack_frame_id);
 477         spin_unlock_irqrestore(&local->ack_status_lock, flags);
 478
 479         if (!skb)
 480                 return;
 481
 482         if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {
 483                 u64 cookie = IEEE80211_SKB_CB(skb)->ack.cookie;
 484                 struct ieee80211_sub_if_data *sdata;
 485                 struct ieee80211_hdr *hdr = (void *)skb->data;
 486
 487                 rcu_read_lock();
 488                 sdata = ieee80211_sdata_from_skb(local, skb);
 489                 if (sdata) {
 490                         if (ieee80211_is_nullfunc(hdr->frame_control) ||
 491                             ieee80211_is_qos_nullfunc(hdr->frame_control))
 492                                 cfg80211_probe_status(sdata->dev, hdr->addr1,
 493                                                       cookie, acked,
 494                                                       info->status.ack_signal,
 495                                                       info->status.is_valid_ack_signal,
 496                                                       GFP_ATOMIC);
 497                         else
 498                                 cfg80211_mgmt_tx_status(&sdata->wdev, cookie,
 499                                                         skb->data, skb->len,
 500                                                         acked, GFP_ATOMIC);
 501                 }
 502                 rcu_read_unlock();
 503
 504                 dev_kfree_skb_any(skb);
 505         } else if (dropped) {
 506                 dev_kfree_skb_any(skb);
 507         } else {
 508                 /* consumes skb */
 509                 skb_complete_wifi_ack(skb, acked);
 510         }
 511 }
 512
 513 static void ieee80211_report_used_skb(struct ieee80211_local *local,
 514                                       struct sk_buff *skb, bool dropped)
 515 {
 516         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 517         struct ieee80211_hdr *hdr = (void *)skb->data;
 518         bool acked = info->flags & IEEE80211_TX_STAT_ACK;
 519
 520         if (dropped)
 521                 acked = false;
 522
 523         if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
 524                 struct ieee80211_sub_if_data *sdata;
 525
 526                 rcu_read_lock();
 527
 528                 sdata = ieee80211_sdata_from_skb(local, skb);
 529
 530                 if (!sdata) {
 531                         skb->dev = NULL;
 532                 } else {
 533                         unsigned int hdr_size =
 534                                 ieee80211_hdrlen(hdr->frame_control);
 535
 536                         /* Check to see if packet is a TDLS teardown packet */
 537                         if (ieee80211_is_data(hdr->frame_control) &&
 538                             (ieee80211_get_tdls_action(skb, hdr_size) ==
 539                              WLAN_TDLS_TEARDOWN))
 540                                 ieee80211_tdls_td_tx_handle(local, sdata, skb,
 541                                                             info->flags);
 542                         else
 543                                 ieee80211_mgd_conn_tx_status(sdata,
 544                                                              hdr->frame_control,
 545                                                              acked);
 546                 }
 547
 548                 rcu_read_unlock();
 549         } else if (info->ack_frame_id) {
 550                 ieee80211_report_ack_skb(local, info, acked, dropped);
 551         }
 552
 553         if (!dropped && skb->destructor) {
 554                 skb->wifi_acked_valid = 1;
 555                 skb->wifi_acked = acked;
 556         }
 557
 558         ieee80211_led_tx(local);
 559 }
 560
 561 /*
 562  * Use a static threshold for now, best value to be determined
 563  * by testing ...
 564  * Should it depend on:
 565  *  - on # of retransmissions
 566  *  - current throughput (higher value for higher tpt)?
 567  */
 568 #define STA_LOST_PKT_THRESHOLD  50
 569 #define STA_LOST_TDLS_PKT_THRESHOLD     10
 570 #define STA_LOST_TDLS_PKT_TIME          (10*HZ) /* 10secs since last ACK */
 571
 572 static void ieee80211_lost_packet(struct sta_info *sta,
 573                                   struct ieee80211_tx_info *info)
 574 {
 575         /* If driver relies on its own algorithm for station kickout, skip
 576          * mac80211 packet loss mechanism.
 577          */
 578         if (ieee80211_hw_check(&sta->local->hw, REPORTS_LOW_ACK))
 579                 return;
 580
 581         /* This packet was aggregated but doesn't carry status info */
 582         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 583             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 584                 return;
 585
 586         sta->status_stats.lost_packets++;
 587         if (!sta->sta.tdls &&
 588             sta->status_stats.lost_packets < STA_LOST_PKT_THRESHOLD)
 589                 return;
 590
 591         /*
 592          * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
 593          * of the last packets were lost, and that no ACK was received in the
 594          * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
 595          * mechanism.
 596          */
 597         if (sta->sta.tdls &&
 598             (sta->status_stats.lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||
 599              time_before(jiffies,
 600                          sta->status_stats.last_tdls_pkt_time +
 601                          STA_LOST_TDLS_PKT_TIME)))
 602                 return;
 603
 604         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 605                                     sta->status_stats.lost_packets, GFP_ATOMIC);
 606         sta->status_stats.lost_packets = 0;
 607 }
 608
 609 static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
 610                                   struct ieee80211_tx_info *info,
 611                                   int *retry_count)
 612 {
 613         int rates_idx = -1;
 614         int count = -1;
 615         int i;
 616
 617         for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 618                 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 619                     !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
 620                         /* just the first aggr frame carry status info */
 621                         info->status.rates[i].idx = -1;
 622                         info->status.rates[i].count = 0;
 623                         break;
 624                 } else if (info->status.rates[i].idx < 0) {
 625                         break;
 626                 } else if (i >= hw->max_report_rates) {
 627                         /* the HW cannot have attempted that rate */
 628                         info->status.rates[i].idx = -1;
 629                         info->status.rates[i].count = 0;
 630                         break;
 631                 }
 632
 633                 count += info->status.rates[i].count;
 634         }
 635         rates_idx = i - 1;
 636
 637         if (count < 0)
 638                 count = 0;
 639
 640         *retry_count = count;
 641         return rates_idx;
 642 }
 643
 644 void ieee80211_tx_monitor(struct ieee80211_local *local, struct sk_buff *skb,
 645                           struct ieee80211_supported_band *sband,
 646                           int retry_count, int shift, bool send_to_cooked)
 647 {
 648         struct sk_buff *skb2;
 649         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 650         struct ieee80211_sub_if_data *sdata;
 651         struct net_device *prev_dev = NULL;
 652         int rtap_len;
 653
 654         /* send frame to monitor interfaces now */
 655         rtap_len = ieee80211_tx_radiotap_len(info);
 656         if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
 657                 pr_err("ieee80211_tx_status: headroom too small\n");
 658                 dev_kfree_skb(skb);
 659                 return;
 660         }
 661         ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
 662                                          rtap_len, shift);
 663
 664         /* XXX: is this sufficient for BPF? */
 665         skb_reset_mac_header(skb);
 666         skb->ip_summed = CHECKSUM_UNNECESSARY;
 667         skb->pkt_type = PACKET_OTHERHOST;
 668         skb->protocol = htons(ETH_P_802_2);
 669         memset(skb->cb, 0, sizeof(skb->cb));
 670
 671         rcu_read_lock();
 672         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 673                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
 674                         if (!ieee80211_sdata_running(sdata))
 675                                 continue;
 676
 677                         if ((sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES) &&
 678                             !send_to_cooked)
 679                                 continue;
 680
 681                         if (prev_dev) {
 682                                 skb2 = skb_clone(skb, GFP_ATOMIC);
 683                                 if (skb2) {
 684                                         skb2->dev = prev_dev;
 685                                         netif_rx(skb2);
 686                                 }
 687                         }
 688
 689                         prev_dev = sdata->dev;
 690                 }
 691         }
 692         if (prev_dev) {
 693                 skb->dev = prev_dev;
 694                 netif_rx(skb);
 695                 skb = NULL;
 696         }
 697         rcu_read_unlock();
 698         dev_kfree_skb(skb);
 699 }
 700
 701 static void __ieee80211_tx_status(struct ieee80211_hw *hw,
 702                                   struct ieee80211_tx_status *status)
 703 {
 704         struct sk_buff *skb = status->skb;
 705         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 706         struct ieee80211_local *local = hw_to_local(hw);
 707         struct ieee80211_tx_info *info = status->info;
 708         struct sta_info *sta;
 709         __le16 fc;
 710         struct ieee80211_supported_band *sband;
 711         int retry_count;
 712         int rates_idx;
 713         bool send_to_cooked;
 714         bool acked;
 715         struct ieee80211_bar *bar;
 716         int shift = 0;
 717         int tid = IEEE80211_NUM_TIDS;
 718
 719         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 720
 721         sband = local->hw.wiphy->bands[info->band];
 722         fc = hdr->frame_control;
 723
 724         if (status->sta) {
 725                 sta = container_of(status->sta, struct sta_info, sta);
 726                 shift = ieee80211_vif_get_shift(&sta->sdata->vif);
 727
 728                 if (info->flags & IEEE80211_TX_STATUS_EOSP)
 729                         clear_sta_flag(sta, WLAN_STA_SP);
 730
 731                 acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 732
 733                 /* mesh Peer Service Period support */
 734                 if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
 735                     ieee80211_is_data_qos(fc))
 736                         ieee80211_mpsp_trigger_process(
 737                                 ieee80211_get_qos_ctl(hdr), sta, true, acked);
 738
 739                 if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
 740                         /*
 741                          * The STA is in power save mode, so assume
 742                          * that this TX packet failed because of that.
 743                          */
 744                         ieee80211_handle_filtered_frame(local, sta, skb);
 745                         return;
 746                 }
 747
 748                 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL) &&
 749                     (ieee80211_is_data(hdr->frame_control)) &&
 750                     (rates_idx != -1))
 751                         sta->tx_stats.last_rate =
 752                                 info->status.rates[rates_idx];
 753
 754                 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
 755                     (ieee80211_is_data_qos(fc))) {
 756                         u16 ssn;
 757                         u8 *qc;
 758
 759                         qc = ieee80211_get_qos_ctl(hdr);
 760                         tid = qc[0] & 0xf;
 761                         ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
 762                                                 & IEEE80211_SCTL_SEQ);
 763                         ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
 764                                            tid, ssn);
 765                 } else if (ieee80211_is_data_qos(fc)) {
 766                         u8 *qc = ieee80211_get_qos_ctl(hdr);
 767
 768                         tid = qc[0] & 0xf;
 769                 }
 770
 771                 if (!acked && ieee80211_is_back_req(fc)) {
 772                         u16 control;
 773
 774                         /*
 775                          * BAR failed, store the last SSN and retry sending
 776                          * the BAR when the next unicast transmission on the
 777                          * same TID succeeds.
 778                          */
 779                         bar = (struct ieee80211_bar *) skb->data;
 780                         control = le16_to_cpu(bar->control);
 781                         if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
 782                                 u16 ssn = le16_to_cpu(bar->start_seq_num);
 783
 784                                 tid = (control &
 785                                        IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
 786                                       IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
 787
 788                                 ieee80211_set_bar_pending(sta, tid, ssn);
 789                         }
 790                 }
 791
 792                 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
 793                         ieee80211_handle_filtered_frame(local, sta, skb);
 794                         return;
 795                 } else {
 796                         if (!acked)
 797                                 sta->status_stats.retry_failed++;
 798                         sta->status_stats.retry_count += retry_count;
 799
 800                         if (ieee80211_is_data_present(fc)) {
 801                                 if (!acked)
 802                                         sta->status_stats.msdu_failed[tid]++;
 803
 804                                 sta->status_stats.msdu_retries[tid] +=
 805                                         retry_count;
 806                         }
 807                 }
 808
 809                 rate_control_tx_status(local, sband, status);
 810                 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
 811                         ieee80211s_update_metric(local, sta, status);
 812
 813                 if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
 814                         ieee80211_frame_acked(sta, skb);
 815
 816                 if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
 817                     ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 818                         ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
 819                                                 acked, info->status.tx_time);
 820
 821                 if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
 822                         if (info->flags & IEEE80211_TX_STAT_ACK) {
 823                                 if (sta->status_stats.lost_packets)
 824                                         sta->status_stats.lost_packets = 0;
 825
 826                                 /* Track when last TDLS packet was ACKed */
 827                                 if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 828                                         sta->status_stats.last_tdls_pkt_time =
 829                                                 jiffies;
 830                         } else {
 831                                 ieee80211_lost_packet(sta, info);
 832                         }
 833                 }
 834         }
 835
 836         /* SNMP counters
 837          * Fragments are passed to low-level drivers as separate skbs, so these
 838          * are actually fragments, not frames. Update frame counters only for
 839          * the first fragment of the frame. */
 840         if ((info->flags & IEEE80211_TX_STAT_ACK) ||
 841             (info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED)) {
 842                 if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
 843                         I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 844                         if (is_multicast_ether_addr(ieee80211_get_DA(hdr)))
 845                                 I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 846                         if (retry_count > 0)
 847                                 I802_DEBUG_INC(local->dot11RetryCount);
 848                         if (retry_count > 1)
 849                                 I802_DEBUG_INC(local->dot11MultipleRetryCount);
 850                 }
 851
 852                 /* This counter shall be incremented for an acknowledged MPDU
 853                  * with an individual address in the address 1 field or an MPDU
 854                  * with a multicast address in the address 1 field of type Data
 855                  * or Management. */
 856                 if (!is_multicast_ether_addr(hdr->addr1) ||
 857                     ieee80211_is_data(fc) ||
 858                     ieee80211_is_mgmt(fc))
 859                         I802_DEBUG_INC(local->dot11TransmittedFragmentCount);
 860         } else {
 861                 if (ieee80211_is_first_frag(hdr->seq_ctrl))
 862                         I802_DEBUG_INC(local->dot11FailedCount);
 863         }
 864
 865         if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
 866             ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS) &&
 867             !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
 868             local->ps_sdata && !(local->scanning)) {
 869                 if (info->flags & IEEE80211_TX_STAT_ACK) {
 870                         local->ps_sdata->u.mgd.flags |=
 871                                         IEEE80211_STA_NULLFUNC_ACKED;
 872                 } else
 873                         mod_timer(&local->dynamic_ps_timer, jiffies +
 874                                         msecs_to_jiffies(10));
 875         }
 876
 877         ieee80211_report_used_skb(local, skb, false);
 878
 879         /* this was a transmitted frame, but now we want to reuse it */
 880         skb_orphan(skb);
 881
 882         /* Need to make a copy before skb->cb gets cleared */
 883         send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
 884                          !(ieee80211_is_data(fc));
 885
 886         /*
 887          * This is a bit racy but we can avoid a lot of work
 888          * with this test...
 889          */
 890         if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
 891                 dev_kfree_skb(skb);
 892                 return;
 893         }
 894
 895         /* send to monitor interfaces */
 896         ieee80211_tx_monitor(local, skb, sband, retry_count, shift, send_to_cooked);
 897 }
 898
 899 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
 900 {
 901         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 902         struct ieee80211_local *local = hw_to_local(hw);
 903         struct ieee80211_tx_status status = {
 904                 .skb = skb,
 905                 .info = IEEE80211_SKB_CB(skb),
 906         };
 907         struct rhlist_head *tmp;
 908         struct sta_info *sta;
 909
 910         rcu_read_lock();
 911
 912         for_each_sta_info(local, hdr->addr1, sta, tmp) {
 913                 /* skip wrong virtual interface */
 914                 if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
 915                         continue;
 916
 917                 status.sta = &sta->sta;
 918                 break;
 919         }
 920
 921         __ieee80211_tx_status(hw, &status);
 922         rcu_read_unlock();
 923 }
 924 EXPORT_SYMBOL(ieee80211_tx_status);
 925
 926 void ieee80211_tx_status_ext(struct ieee80211_hw *hw,
 927                              struct ieee80211_tx_status *status)
 928 {
 929         struct ieee80211_local *local = hw_to_local(hw);
 930         struct ieee80211_tx_info *info = status->info;
 931         struct ieee80211_sta *pubsta = status->sta;
 932         struct ieee80211_supported_band *sband;
 933         int retry_count;
 934         bool acked, noack_success;
 935
 936         if (status->skb)
 937                 return __ieee80211_tx_status(hw, status);
 938
 939         if (!status->sta)
 940                 return;
 941
 942         ieee80211_tx_get_rates(hw, info, &retry_count);
 943
 944         sband = hw->wiphy->bands[info->band];
 945
 946         acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 947         noack_success = !!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED);
 948
 949         if (pubsta) {
 950                 struct sta_info *sta;
 951
 952                 sta = container_of(pubsta, struct sta_info, sta);
 953
 954                 if (!acked)
 955                         sta->status_stats.retry_failed++;
 956                 sta->status_stats.retry_count += retry_count;
 957
 958                 if (acked) {
 959                         sta->status_stats.last_ack = jiffies;
 960
 961                         if (sta->status_stats.lost_packets)
 962                                 sta->status_stats.lost_packets = 0;
 963
 964                         /* Track when last TDLS packet was ACKed */
 965                         if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 966                                 sta->status_stats.last_tdls_pkt_time = jiffies;
 967                 } else {
 968                         ieee80211_lost_packet(sta, info);
 969                 }
 970
 971                 rate_control_tx_status(local, sband, status);
 972                 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
 973                         ieee80211s_update_metric(local, sta, status);
 974         }
 975
 976         if (acked || noack_success) {
 977                 I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 978                 if (!pubsta)
 979                         I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 980                 if (retry_count > 0)
 981                         I802_DEBUG_INC(local->dot11RetryCount);
 982                 if (retry_count > 1)
 983                         I802_DEBUG_INC(local->dot11MultipleRetryCount);
 984         } else {
 985                 I802_DEBUG_INC(local->dot11FailedCount);
 986         }
 987 }
 988 EXPORT_SYMBOL(ieee80211_tx_status_ext);
 989
 990 void ieee80211_tx_rate_update(struct ieee80211_hw *hw,
 991                               struct ieee80211_sta *pubsta,
 992                               struct ieee80211_tx_info *info)
 993 {
 994         struct ieee80211_local *local = hw_to_local(hw);
 995         struct ieee80211_supported_band *sband = hw->wiphy->bands[info->band];
 996         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 997         struct ieee80211_tx_status status = {
 998                 .info = info,
 999                 .sta = pubsta,
1000         };
1001
1002         rate_control_tx_status(local, sband, &status);
1003
1004         if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL))
1005                 sta->tx_stats.last_rate = info->status.rates[0];
1006 }
1007 EXPORT_SYMBOL(ieee80211_tx_rate_update);
1008
1009 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
1010 {
1011         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1012         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
1013                                     num_packets, GFP_ATOMIC);
1014 }
1015 EXPORT_SYMBOL(ieee80211_report_low_ack);
1016
1017 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
1018 {
1019         struct ieee80211_local *local = hw_to_local(hw);
1020
1021         ieee80211_report_used_skb(local, skb, true);
1022         dev_kfree_skb_any(skb);
1023 }
1024 EXPORT_SYMBOL(ieee80211_free_txskb);
1025
1026 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
1027                               struct sk_buff_head *skbs)
1028 {
1029         struct sk_buff *skb;
1030
1031         while ((skb = __skb_dequeue(skbs)))
1032                 ieee80211_free_txskb(hw, skb);
1033 }