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