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 <[email protected]>
   5  * Copyright 2008-2010  Johannes Berg <[email protected]>
   6  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/export.h>
  14 #include <linux/etherdevice.h>
  15 #include <net/mac80211.h>
  16 #include <asm/unaligned.h>
  17 #include "ieee80211_i.h"
  18 #include "rate.h"
  19 #include "mesh.h"
  20 #include "led.h"
  21 #include "wme.h"
  22
  23
  24 void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
  25                                  struct sk_buff *skb)
  26 {
  27         struct ieee80211_local *local = hw_to_local(hw);
  28         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  29         int tmp;
  30
  31         skb->pkt_type = IEEE80211_TX_STATUS_MSG;
  32         skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
  33                        &local->skb_queue : &local->skb_queue_unreliable, skb);
  34         tmp = skb_queue_len(&local->skb_queue) +
  35                 skb_queue_len(&local->skb_queue_unreliable);
  36         while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
  37                (skb = skb_dequeue(&local->skb_queue_unreliable))) {
  38                 ieee80211_free_txskb(hw, skb);
  39                 tmp--;
  40                 I802_DEBUG_INC(local->tx_status_drop);
  41         }
  42         tasklet_schedule(&local->tasklet);
  43 }
  44 EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
  45
  46 static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
  47                                             struct sta_info *sta,
  48                                             struct sk_buff *skb)
  49 {
  50         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  51         struct ieee80211_hdr *hdr = (void *)skb->data;
  52         int ac;
  53
  54         if (info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
  55                            IEEE80211_TX_CTL_AMPDU)) {
  56                 ieee80211_free_txskb(&local->hw, skb);
  57                 return;
  58         }
  59
  60         /*
  61          * This skb 'survived' a round-trip through the driver, and
  62          * hopefully the driver didn't mangle it too badly. However,
  63          * we can definitely not rely on the control information
  64          * being correct. Clear it so we don't get junk there, and
  65          * indicate that it needs new processing, but must not be
  66          * modified/encrypted again.
  67          */
  68         memset(&info->control, 0, sizeof(info->control));
  69
  70         info->control.jiffies = jiffies;
  71         info->control.vif = &sta->sdata->vif;
  72         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
  73                        IEEE80211_TX_INTFL_RETRANSMISSION;
  74         info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
  75
  76         sta->status_stats.filtered++;
  77
  78         /*
  79          * Clear more-data bit on filtered frames, it might be set
  80          * but later frames might time out so it might have to be
  81          * clear again ... It's all rather unlikely (this frame
  82          * should time out first, right?) but let's not confuse
  83          * peers unnecessarily.
  84          */
  85         if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
  86                 hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);
  87
  88         if (ieee80211_is_data_qos(hdr->frame_control)) {
  89                 u8 *p = ieee80211_get_qos_ctl(hdr);
  90                 int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
  91
  92                 /*
  93                  * Clear EOSP if set, this could happen e.g.
  94                  * if an absence period (us being a P2P GO)
  95                  * shortens the SP.
  96                  */
  97                 if (*p & IEEE80211_QOS_CTL_EOSP)
  98                         *p &= ~IEEE80211_QOS_CTL_EOSP;
  99                 ac = ieee80211_ac_from_tid(tid);
 100         } else {
 101                 ac = IEEE80211_AC_BE;
 102         }
 103
 104         /*
 105          * Clear the TX filter mask for this STA when sending the next
 106          * packet. If the STA went to power save mode, this will happen
 107          * when it wakes up for the next time.
 108          */
 109         set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
 110         ieee80211_clear_fast_xmit(sta);
 111
 112         /*
 113          * This code races in the following way:
 114          *
 115          *  (1) STA sends frame indicating it will go to sleep and does so
 116          *  (2) hardware/firmware adds STA to filter list, passes frame up
 117          *  (3) hardware/firmware processes TX fifo and suppresses a frame
 118          *  (4) we get TX status before having processed the frame and
 119          *      knowing that the STA has gone to sleep.
 120          *
 121          * This is actually quite unlikely even when both those events are
 122          * processed from interrupts coming in quickly after one another or
 123          * even at the same time because we queue both TX status events and
 124          * RX frames to be processed by a tasklet and process them in the
 125          * same order that they were received or TX status last. Hence, there
 126          * is no race as long as the frame RX is processed before the next TX
 127          * status, which drivers can ensure, see below.
 128          *
 129          * Note that this can only happen if the hardware or firmware can
 130          * actually add STAs to the filter list, if this is done by the
 131          * driver in response to set_tim() (which will only reduce the race
 132          * this whole filtering tries to solve, not completely solve it)
 133          * this situation cannot happen.
 134          *
 135          * To completely solve this race drivers need to make sure that they
 136          *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
 137          *      functions and
 138          *  (b) always process RX events before TX status events if ordering
 139          *      can be unknown, for example with different interrupt status
 140          *      bits.
 141          *  (c) if PS mode transitions are manual (i.e. the flag
 142          *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
 143          *      changes before calling TX status events if ordering can be
 144          *      unknown.
 145          */
 146         if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
 147             skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
 148                 skb_queue_tail(&sta->tx_filtered[ac], skb);
 149                 sta_info_recalc_tim(sta);
 150
 151                 if (!timer_pending(&local->sta_cleanup))
 152                         mod_timer(&local->sta_cleanup,
 153                                   round_jiffies(jiffies +
 154                                                 STA_INFO_CLEANUP_INTERVAL));
 155                 return;
 156         }
 157
 158         if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
 159             !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
 160                 /* Software retry the packet once */
 161                 info->flags |= IEEE80211_TX_INTFL_RETRIED;
 162                 ieee80211_add_pending_skb(local, skb);
 163                 return;
 164         }
 165
 166         ps_dbg_ratelimited(sta->sdata,
 167                            "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
 168                            skb_queue_len(&sta->tx_filtered[ac]),
 169                            !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);
 170         ieee80211_free_txskb(&local->hw, skb);
 171 }
 172
 173 static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
 174 {
 175         struct tid_ampdu_tx *tid_tx;
 176
 177         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 178         if (!tid_tx || !tid_tx->bar_pending)
 179                 return;
 180
 181         tid_tx->bar_pending = false;
 182         ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);
 183 }
 184
 185 static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
 186 {
 187         struct ieee80211_mgmt *mgmt = (void *) skb->data;
 188         struct ieee80211_local *local = sta->local;
 189         struct ieee80211_sub_if_data *sdata = sta->sdata;
 190
 191         if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 192                 sta->status_stats.last_ack = jiffies;
 193
 194         if (ieee80211_is_data_qos(mgmt->frame_control)) {
 195                 struct ieee80211_hdr *hdr = (void *) skb->data;
 196                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 197                 u16 tid = qc[0] & 0xf;
 198
 199                 ieee80211_check_pending_bar(sta, hdr->addr1, tid);
 200         }
 201
 202         if (ieee80211_is_action(mgmt->frame_control) &&
 203             !ieee80211_has_protected(mgmt->frame_control) &&
 204             mgmt->u.action.category == WLAN_CATEGORY_HT &&
 205             mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
 206             ieee80211_sdata_running(sdata)) {
 207                 enum ieee80211_smps_mode smps_mode;
 208
 209                 switch (mgmt->u.action.u.ht_smps.smps_control) {
 210                 case WLAN_HT_SMPS_CONTROL_DYNAMIC:
 211                         smps_mode = IEEE80211_SMPS_DYNAMIC;
 212                         break;
 213                 case WLAN_HT_SMPS_CONTROL_STATIC:
 214                         smps_mode = IEEE80211_SMPS_STATIC;
 215                         break;
 216                 case WLAN_HT_SMPS_CONTROL_DISABLED:
 217                 default: /* shouldn't happen since we don't send that */
 218                         smps_mode = IEEE80211_SMPS_OFF;
 219                         break;
 220                 }
 221
 222                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 223                         /*
 224                          * This update looks racy, but isn't -- if we come
 225                          * here we've definitely got a station that we're
 226                          * talking to, and on a managed interface that can
 227                          * only be the AP. And the only other place updating
 228                          * this variable in managed mode is before association.
 229                          */
 230                         sdata->smps_mode = smps_mode;
 231                         ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
 232                 } else if (sdata->vif.type == NL80211_IFTYPE_AP ||
 233                            sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 234                         sta->known_smps_mode = smps_mode;
 235                 }
 236         }
 237 }
 238
 239 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
 240 {
 241         struct tid_ampdu_tx *tid_tx;
 242
 243         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 244         if (!tid_tx)
 245                 return;
 246
 247         tid_tx->failed_bar_ssn = ssn;
 248         tid_tx->bar_pending = true;
 249 }
 250
 251 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
 252 {
 253         int len = sizeof(struct ieee80211_radiotap_header);
 254
 255         /* IEEE80211_RADIOTAP_RATE rate */
 256         if (info->status.rates[0].idx >= 0 &&
 257             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 258                                              IEEE80211_TX_RC_VHT_MCS)))
 259                 len += 2;
 260
 261         /* IEEE80211_RADIOTAP_TX_FLAGS */
 262         len += 2;
 263
 264         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 265         len += 1;
 266
 267         /* IEEE80211_RADIOTAP_MCS
 268          * IEEE80211_RADIOTAP_VHT */
 269         if (info->status.rates[0].idx >= 0) {
 270                 if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
 271                         len += 3;
 272                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
 273                         len = ALIGN(len, 2) + 12;
 274         }
 275
 276         return len;
 277 }
 278
 279 static void
 280 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
 281                                  struct ieee80211_supported_band *sband,
 282                                  struct sk_buff *skb, int retry_count,
 283                                  int rtap_len, int shift)
 284 {
 285         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 286         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 287         struct ieee80211_radiotap_header *rthdr;
 288         unsigned char *pos;
 289         u16 txflags;
 290
 291         rthdr = skb_push(skb, rtap_len);
 292
 293         memset(rthdr, 0, rtap_len);
 294         rthdr->it_len = cpu_to_le16(rtap_len);
 295         rthdr->it_present =
 296                 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
 297                             (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
 298         pos = (unsigned char *)(rthdr + 1);
 299
 300         /*
 301          * XXX: Once radiotap gets the bitmap reset thing the vendor
 302          *      extensions proposal contains, we can actually report
 303          *      the whole set of tries we did.
 304          */
 305
 306         /* IEEE80211_RADIOTAP_RATE */
 307         if (info->status.rates[0].idx >= 0 &&
 308             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 309                                              IEEE80211_TX_RC_VHT_MCS))) {
 310                 u16 rate;
 311
 312                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 313                 rate = sband->bitrates[info->status.rates[0].idx].bitrate;
 314                 *pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
 315                 /* padding for tx flags */
 316                 pos += 2;
 317         }
 318
 319         /* IEEE80211_RADIOTAP_TX_FLAGS */
 320         txflags = 0;
 321         if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
 322             !is_multicast_ether_addr(hdr->addr1))
 323                 txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
 324
 325         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
 326                 txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
 327         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
 328                 txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
 329
 330         put_unaligned_le16(txflags, pos);
 331         pos += 2;
 332
 333         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 334         /* for now report the total retry_count */
 335         *pos = retry_count;
 336         pos++;
 337
 338         if (info->status.rates[0].idx < 0)
 339                 return;
 340
 341         /* IEEE80211_RADIOTAP_MCS
 342          * IEEE80211_RADIOTAP_VHT */
 343         if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
 344                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 345                 pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
 346                          IEEE80211_RADIOTAP_MCS_HAVE_GI |
 347                          IEEE80211_RADIOTAP_MCS_HAVE_BW;
 348                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 349                         pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
 350                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 351                         pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
 352                 if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
 353                         pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 354                 pos[2] = info->status.rates[0].idx;
 355                 pos += 3;
 356         } else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
 357                 u16 known = local->hw.radiotap_vht_details &
 358                         (IEEE80211_RADIOTAP_VHT_KNOWN_GI |
 359                          IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
 360
 361                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 362
 363                 /* required alignment from rthdr */
 364                 pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
 365
 366                 /* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
 367                 put_unaligned_le16(known, pos);
 368                 pos += 2;
 369
 370                 /* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
 371                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 372                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 373                 pos++;
 374
 375                 /* u8 bandwidth */
 376                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 377                         *pos = 1;
 378                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
 379                         *pos = 4;
 380                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
 381                         *pos = 11;
 382                 else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
 383                         *pos = 0;
 384                 pos++;
 385
 386                 /* u8 mcs_nss[4] */
 387                 *pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
 388                         ieee80211_rate_get_vht_nss(&info->status.rates[0]);
 389                 pos += 4;
 390
 391                 /* u8 coding */
 392                 pos++;
 393                 /* u8 group_id */
 394                 pos++;
 395                 /* u16 partial_aid */
 396                 pos += 2;
 397         }
 398 }
 399
 400 /*
 401  * Handles the tx for TDLS teardown frames.
 402  * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
 403  */
 404 static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
 405                                         struct ieee80211_sub_if_data *sdata,
 406                                         struct sk_buff *skb, u32 flags)
 407 {
 408         struct sk_buff *teardown_skb;
 409         struct sk_buff *orig_teardown_skb;
 410         bool is_teardown = false;
 411
 412         /* Get the teardown data we need and free the lock */
 413         spin_lock(&sdata->u.mgd.teardown_lock);
 414         teardown_skb = sdata->u.mgd.teardown_skb;
 415         orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
 416         if ((skb == orig_teardown_skb) && teardown_skb) {
 417                 sdata->u.mgd.teardown_skb = NULL;
 418                 sdata->u.mgd.orig_teardown_skb = NULL;
 419                 is_teardown = true;
 420         }
 421         spin_unlock(&sdata->u.mgd.teardown_lock);
 422
 423         if (is_teardown) {
 424                 /* This mechanism relies on being able to get ACKs */
 425                 WARN_ON(!ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS));
 426
 427                 /* Check if peer has ACKed */
 428                 if (flags & IEEE80211_TX_STAT_ACK) {
 429                         dev_kfree_skb_any(teardown_skb);
 430                 } else {
 431                         tdls_dbg(sdata,
 432                                  "TDLS Resending teardown through AP\n");
 433
 434                         ieee80211_subif_start_xmit(teardown_skb, skb->dev);
 435                 }
 436         }
 437 }
 438
 439 static struct ieee80211_sub_if_data *
 440 ieee80211_sdata_from_skb(struct ieee80211_local *local, struct sk_buff *skb)
 441 {
 442         struct ieee80211_sub_if_data *sdata;
 443
 444         if (skb->dev) {
 445                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 446                         if (!sdata->dev)
 447                                 continue;
 448
 449                         if (skb->dev == sdata->dev)
 450                                 return sdata;
 451                 }
 452
 453                 return NULL;
 454         }
 455
 456         return rcu_dereference(local->p2p_sdata);
 457 }
 458
 459 static void ieee80211_report_ack_skb(struct ieee80211_local *local,
 460                                      struct ieee80211_tx_info *info,
 461                                      bool acked, bool dropped)
 462 {
 463         struct sk_buff *skb;
 464         unsigned long flags;
 465
 466         spin_lock_irqsave(&local->ack_status_lock, flags);
 467         skb = idr_remove(&local->ack_status_frames, info->ack_frame_id);
 468         spin_unlock_irqrestore(&local->ack_status_lock, flags);
 469
 470         if (!skb)
 471                 return;
 472
 473         if (dropped) {
 474                 dev_kfree_skb_any(skb);
 475                 return;
 476         }
 477
 478         if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {
 479                 u64 cookie = IEEE80211_SKB_CB(skb)->ack.cookie;
 480                 struct ieee80211_sub_if_data *sdata;
 481                 struct ieee80211_hdr *hdr = (void *)skb->data;
 482
 483                 rcu_read_lock();
 484                 sdata = ieee80211_sdata_from_skb(local, skb);
 485                 if (sdata) {
 486                         if (ieee80211_is_nullfunc(hdr->frame_control) ||
 487                             ieee80211_is_qos_nullfunc(hdr->frame_control))
 488                                 cfg80211_probe_status(sdata->dev, hdr->addr1,
 489                                                       cookie, acked,
 490                                                       GFP_ATOMIC);
 491                         else
 492                                 cfg80211_mgmt_tx_status(&sdata->wdev, cookie,
 493                                                         skb->data, skb->len,
 494                                                         acked, GFP_ATOMIC);
 495                 }
 496                 rcu_read_unlock();
 497
 498                 dev_kfree_skb_any(skb);
 499         } else {
 500                 /* consumes skb */
 501                 skb_complete_wifi_ack(skb, acked);
 502         }
 503 }
 504
 505 static void ieee80211_report_used_skb(struct ieee80211_local *local,
 506                                       struct sk_buff *skb, bool dropped)
 507 {
 508         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 509         struct ieee80211_hdr *hdr = (void *)skb->data;
 510         bool acked = info->flags & IEEE80211_TX_STAT_ACK;
 511
 512         if (dropped)
 513                 acked = false;
 514
 515         if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
 516                 struct ieee80211_sub_if_data *sdata;
 517
 518                 rcu_read_lock();
 519
 520                 sdata = ieee80211_sdata_from_skb(local, skb);
 521
 522                 if (!sdata) {
 523                         skb->dev = NULL;
 524                 } else {
 525                         unsigned int hdr_size =
 526                                 ieee80211_hdrlen(hdr->frame_control);
 527
 528                         /* Check to see if packet is a TDLS teardown packet */
 529                         if (ieee80211_is_data(hdr->frame_control) &&
 530                             (ieee80211_get_tdls_action(skb, hdr_size) ==
 531                              WLAN_TDLS_TEARDOWN))
 532                                 ieee80211_tdls_td_tx_handle(local, sdata, skb,
 533                                                             info->flags);
 534                         else
 535                                 ieee80211_mgd_conn_tx_status(sdata,
 536                                                              hdr->frame_control,
 537                                                              acked);
 538                 }
 539
 540                 rcu_read_unlock();
 541         } else if (info->ack_frame_id) {
 542                 ieee80211_report_ack_skb(local, info, acked, dropped);
 543         }
 544
 545         if (!dropped && skb->destructor) {
 546                 skb->wifi_acked_valid = 1;
 547                 skb->wifi_acked = acked;
 548         }
 549
 550         ieee80211_led_tx(local);
 551 }
 552
 553 /*
 554  * Use a static threshold for now, best value to be determined
 555  * by testing ...
 556  * Should it depend on:
 557  *  - on # of retransmissions
 558  *  - current throughput (higher value for higher tpt)?
 559  */
 560 #define STA_LOST_PKT_THRESHOLD  50
 561 #define STA_LOST_TDLS_PKT_THRESHOLD     10
 562 #define STA_LOST_TDLS_PKT_TIME          (10*HZ) /* 10secs since last ACK */
 563
 564 static void ieee80211_lost_packet(struct sta_info *sta,
 565                                   struct ieee80211_tx_info *info)
 566 {
 567         /* If driver relies on its own algorithm for station kickout, skip
 568          * mac80211 packet loss mechanism.
 569          */
 570         if (ieee80211_hw_check(&sta->local->hw, REPORTS_LOW_ACK))
 571                 return;
 572
 573         /* This packet was aggregated but doesn't carry status info */
 574         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 575             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 576                 return;
 577
 578         sta->status_stats.lost_packets++;
 579         if (!sta->sta.tdls &&
 580             sta->status_stats.lost_packets < STA_LOST_PKT_THRESHOLD)
 581                 return;
 582
 583         /*
 584          * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
 585          * of the last packets were lost, and that no ACK was received in the
 586          * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
 587          * mechanism.
 588          */
 589         if (sta->sta.tdls &&
 590             (sta->status_stats.lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||
 591              time_before(jiffies,
 592                          sta->status_stats.last_tdls_pkt_time +
 593                          STA_LOST_TDLS_PKT_TIME)))
 594                 return;
 595
 596         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 597                                     sta->status_stats.lost_packets, GFP_ATOMIC);
 598         sta->status_stats.lost_packets = 0;
 599 }
 600
 601 static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
 602                                   struct ieee80211_tx_info *info,
 603                                   int *retry_count)
 604 {
 605         int rates_idx = -1;
 606         int count = -1;
 607         int i;
 608
 609         for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 610                 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 611                     !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
 612                         /* just the first aggr frame carry status info */
 613                         info->status.rates[i].idx = -1;
 614                         info->status.rates[i].count = 0;
 615                         break;
 616                 } else if (info->status.rates[i].idx < 0) {
 617                         break;
 618                 } else if (i >= hw->max_report_rates) {
 619                         /* the HW cannot have attempted that rate */
 620                         info->status.rates[i].idx = -1;
 621                         info->status.rates[i].count = 0;
 622                         break;
 623                 }
 624
 625                 count += info->status.rates[i].count;
 626         }
 627         rates_idx = i - 1;
 628
 629         if (count < 0)
 630                 count = 0;
 631
 632         *retry_count = count;
 633         return rates_idx;
 634 }
 635
 636 void ieee80211_tx_monitor(struct ieee80211_local *local, struct sk_buff *skb,
 637                           struct ieee80211_supported_band *sband,
 638                           int retry_count, int shift, bool send_to_cooked)
 639 {
 640         struct sk_buff *skb2;
 641         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 642         struct ieee80211_sub_if_data *sdata;
 643         struct net_device *prev_dev = NULL;
 644         int rtap_len;
 645
 646         /* send frame to monitor interfaces now */
 647         rtap_len = ieee80211_tx_radiotap_len(info);
 648         if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
 649                 pr_err("ieee80211_tx_status: headroom too small\n");
 650                 dev_kfree_skb(skb);
 651                 return;
 652         }
 653         ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
 654                                          rtap_len, shift);
 655
 656         /* XXX: is this sufficient for BPF? */
 657         skb_reset_mac_header(skb);
 658         skb->ip_summed = CHECKSUM_UNNECESSARY;
 659         skb->pkt_type = PACKET_OTHERHOST;
 660         skb->protocol = htons(ETH_P_802_2);
 661         memset(skb->cb, 0, sizeof(skb->cb));
 662
 663         rcu_read_lock();
 664         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 665                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
 666                         if (!ieee80211_sdata_running(sdata))
 667                                 continue;
 668
 669                         if ((sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES) &&
 670                             !send_to_cooked)
 671                                 continue;
 672
 673                         if (prev_dev) {
 674                                 skb2 = skb_clone(skb, GFP_ATOMIC);
 675                                 if (skb2) {
 676                                         skb2->dev = prev_dev;
 677                                         netif_rx(skb2);
 678                                 }
 679                         }
 680
 681                         prev_dev = sdata->dev;
 682                 }
 683         }
 684         if (prev_dev) {
 685                 skb->dev = prev_dev;
 686                 netif_rx(skb);
 687                 skb = NULL;
 688         }
 689         rcu_read_unlock();
 690         dev_kfree_skb(skb);
 691 }
 692
 693 static void __ieee80211_tx_status(struct ieee80211_hw *hw,
 694                                   struct ieee80211_tx_status *status)
 695 {
 696         struct sk_buff *skb = status->skb;
 697         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 698         struct ieee80211_local *local = hw_to_local(hw);
 699         struct ieee80211_tx_info *info = status->info;
 700         struct sta_info *sta;
 701         __le16 fc;
 702         struct ieee80211_supported_band *sband;
 703         int retry_count;
 704         int rates_idx;
 705         bool send_to_cooked;
 706         bool acked;
 707         struct ieee80211_bar *bar;
 708         int shift = 0;
 709         int tid = IEEE80211_NUM_TIDS;
 710
 711         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 712
 713         sband = local->hw.wiphy->bands[info->band];
 714         fc = hdr->frame_control;
 715
 716         if (status->sta) {
 717                 sta = container_of(status->sta, struct sta_info, sta);
 718                 shift = ieee80211_vif_get_shift(&sta->sdata->vif);
 719
 720                 if (info->flags & IEEE80211_TX_STATUS_EOSP)
 721                         clear_sta_flag(sta, WLAN_STA_SP);
 722
 723                 acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 724
 725                 /* mesh Peer Service Period support */
 726                 if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
 727                     ieee80211_is_data_qos(fc))
 728                         ieee80211_mpsp_trigger_process(
 729                                 ieee80211_get_qos_ctl(hdr), sta, true, acked);
 730
 731                 if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
 732                         /*
 733                          * The STA is in power save mode, so assume
 734                          * that this TX packet failed because of that.
 735                          */
 736                         ieee80211_handle_filtered_frame(local, sta, skb);
 737                         return;
 738                 }
 739
 740                 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL) &&
 741                     (ieee80211_is_data(hdr->frame_control)) &&
 742                     (rates_idx != -1))
 743                         sta->tx_stats.last_rate =
 744                                 info->status.rates[rates_idx];
 745
 746                 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
 747                     (ieee80211_is_data_qos(fc))) {
 748                         u16 ssn;
 749                         u8 *qc;
 750
 751                         qc = ieee80211_get_qos_ctl(hdr);
 752                         tid = qc[0] & 0xf;
 753                         ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
 754                                                 & IEEE80211_SCTL_SEQ);
 755                         ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
 756                                            tid, ssn);
 757                 } else if (ieee80211_is_data_qos(fc)) {
 758                         u8 *qc = ieee80211_get_qos_ctl(hdr);
 759
 760                         tid = qc[0] & 0xf;
 761                 }
 762
 763                 if (!acked && ieee80211_is_back_req(fc)) {
 764                         u16 control;
 765
 766                         /*
 767                          * BAR failed, store the last SSN and retry sending
 768                          * the BAR when the next unicast transmission on the
 769                          * same TID succeeds.
 770                          */
 771                         bar = (struct ieee80211_bar *) skb->data;
 772                         control = le16_to_cpu(bar->control);
 773                         if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
 774                                 u16 ssn = le16_to_cpu(bar->start_seq_num);
 775
 776                                 tid = (control &
 777                                        IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
 778                                       IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
 779
 780                                 ieee80211_set_bar_pending(sta, tid, ssn);
 781                         }
 782                 }
 783
 784                 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
 785                         ieee80211_handle_filtered_frame(local, sta, skb);
 786                         return;
 787                 } else {
 788                         if (!acked)
 789                                 sta->status_stats.retry_failed++;
 790                         sta->status_stats.retry_count += retry_count;
 791
 792                         if (ieee80211_is_data_present(fc)) {
 793                                 if (!acked)
 794                                         sta->status_stats.msdu_failed[tid]++;
 795
 796                                 sta->status_stats.msdu_retries[tid] +=
 797                                         retry_count;
 798                         }
 799                 }
 800
 801                 rate_control_tx_status(local, sband, status);
 802                 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
 803                         ieee80211s_update_metric(local, sta, skb);
 804
 805                 if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
 806                         ieee80211_frame_acked(sta, skb);
 807
 808                 if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
 809                     ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 810                         ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
 811                                                 acked, info->status.tx_time);
 812
 813                 if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
 814                         if (info->flags & IEEE80211_TX_STAT_ACK) {
 815                                 if (sta->status_stats.lost_packets)
 816                                         sta->status_stats.lost_packets = 0;
 817
 818                                 /* Track when last TDLS packet was ACKed */
 819                                 if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 820                                         sta->status_stats.last_tdls_pkt_time =
 821                                                 jiffies;
 822                         } else {
 823                                 ieee80211_lost_packet(sta, info);
 824                         }
 825                 }
 826         }
 827
 828         /* SNMP counters
 829          * Fragments are passed to low-level drivers as separate skbs, so these
 830          * are actually fragments, not frames. Update frame counters only for
 831          * the first fragment of the frame. */
 832         if ((info->flags & IEEE80211_TX_STAT_ACK) ||
 833             (info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED)) {
 834                 if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
 835                         I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 836                         if (is_multicast_ether_addr(ieee80211_get_DA(hdr)))
 837                                 I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 838                         if (retry_count > 0)
 839                                 I802_DEBUG_INC(local->dot11RetryCount);
 840                         if (retry_count > 1)
 841                                 I802_DEBUG_INC(local->dot11MultipleRetryCount);
 842                 }
 843
 844                 /* This counter shall be incremented for an acknowledged MPDU
 845                  * with an individual address in the address 1 field or an MPDU
 846                  * with a multicast address in the address 1 field of type Data
 847                  * or Management. */
 848                 if (!is_multicast_ether_addr(hdr->addr1) ||
 849                     ieee80211_is_data(fc) ||
 850                     ieee80211_is_mgmt(fc))
 851                         I802_DEBUG_INC(local->dot11TransmittedFragmentCount);
 852         } else {
 853                 if (ieee80211_is_first_frag(hdr->seq_ctrl))
 854                         I802_DEBUG_INC(local->dot11FailedCount);
 855         }
 856
 857         if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
 858             ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS) &&
 859             !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
 860             local->ps_sdata && !(local->scanning)) {
 861                 if (info->flags & IEEE80211_TX_STAT_ACK) {
 862                         local->ps_sdata->u.mgd.flags |=
 863                                         IEEE80211_STA_NULLFUNC_ACKED;
 864                 } else
 865                         mod_timer(&local->dynamic_ps_timer, jiffies +
 866                                         msecs_to_jiffies(10));
 867         }
 868
 869         ieee80211_report_used_skb(local, skb, false);
 870
 871         /* this was a transmitted frame, but now we want to reuse it */
 872         skb_orphan(skb);
 873
 874         /* Need to make a copy before skb->cb gets cleared */
 875         send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
 876                          !(ieee80211_is_data(fc));
 877
 878         /*
 879          * This is a bit racy but we can avoid a lot of work
 880          * with this test...
 881          */
 882         if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
 883                 dev_kfree_skb(skb);
 884                 return;
 885         }
 886
 887         /* send to monitor interfaces */
 888         ieee80211_tx_monitor(local, skb, sband, retry_count, shift, send_to_cooked);
 889 }
 890
 891 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
 892 {
 893         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 894         struct ieee80211_local *local = hw_to_local(hw);
 895         struct ieee80211_tx_status status = {
 896                 .skb = skb,
 897                 .info = IEEE80211_SKB_CB(skb),
 898         };
 899         struct rhlist_head *tmp;
 900         struct sta_info *sta;
 901
 902         rcu_read_lock();
 903
 904         for_each_sta_info(local, hdr->addr1, sta, tmp) {
 905                 /* skip wrong virtual interface */
 906                 if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
 907                         continue;
 908
 909                 status.sta = &sta->sta;
 910                 break;
 911         }
 912
 913         __ieee80211_tx_status(hw, &status);
 914         rcu_read_unlock();
 915 }
 916 EXPORT_SYMBOL(ieee80211_tx_status);
 917
 918 void ieee80211_tx_status_ext(struct ieee80211_hw *hw,
 919                              struct ieee80211_tx_status *status)
 920 {
 921         struct ieee80211_local *local = hw_to_local(hw);
 922         struct ieee80211_tx_info *info = status->info;
 923         struct ieee80211_sta *pubsta = status->sta;
 924         struct ieee80211_supported_band *sband;
 925         int retry_count;
 926         bool acked, noack_success;
 927
 928         if (status->skb)
 929                 return __ieee80211_tx_status(hw, status);
 930
 931         if (!status->sta)
 932                 return;
 933
 934         ieee80211_tx_get_rates(hw, info, &retry_count);
 935
 936         sband = hw->wiphy->bands[info->band];
 937
 938         acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 939         noack_success = !!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED);
 940
 941         if (pubsta) {
 942                 struct sta_info *sta;
 943
 944                 sta = container_of(pubsta, struct sta_info, sta);
 945
 946                 if (!acked)
 947                         sta->status_stats.retry_failed++;
 948                 sta->status_stats.retry_count += retry_count;
 949
 950                 if (acked) {
 951                         sta->status_stats.last_ack = jiffies;
 952
 953                         if (sta->status_stats.lost_packets)
 954                                 sta->status_stats.lost_packets = 0;
 955
 956                         /* Track when last TDLS packet was ACKed */
 957                         if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 958                                 sta->status_stats.last_tdls_pkt_time = jiffies;
 959                 } else {
 960                         ieee80211_lost_packet(sta, info);
 961                 }
 962
 963                 rate_control_tx_status(local, sband, status);
 964         }
 965
 966         if (acked || noack_success) {
 967                 I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 968                 if (!pubsta)
 969                         I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 970                 if (retry_count > 0)
 971                         I802_DEBUG_INC(local->dot11RetryCount);
 972                 if (retry_count > 1)
 973                         I802_DEBUG_INC(local->dot11MultipleRetryCount);
 974         } else {
 975                 I802_DEBUG_INC(local->dot11FailedCount);
 976         }
 977 }
 978 EXPORT_SYMBOL(ieee80211_tx_status_ext);
 979
 980 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
 981 {
 982         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 983         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 984                                     num_packets, GFP_ATOMIC);
 985 }
 986 EXPORT_SYMBOL(ieee80211_report_low_ack);
 987
 988 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
 989 {
 990         struct ieee80211_local *local = hw_to_local(hw);
 991
 992         ieee80211_report_used_skb(local, skb, true);
 993         dev_kfree_skb_any(skb);
 994 }
 995 EXPORT_SYMBOL(ieee80211_free_txskb);
 996
 997 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
 998                               struct sk_buff_head *skbs)
 999 {
1000         struct sk_buff *skb;
1001
1002         while ((skb = __skb_dequeue(skbs)))
1003                 ieee80211_free_txskb(hw, skb);
1004 }