net/mac80211/status.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2008-2010  Johannes Berg <johannes@sipsolutions.net>
   6  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/export.h>
  14 #include <linux/etherdevice.h>
  15 #include <net/mac80211.h>
  16 #include <asm/unaligned.h>
  17 #include "ieee80211_i.h"
  18 #include "rate.h"
  19 #include "mesh.h"
  20 #include "led.h"
  21 #include "wme.h"
  22
  23
  24 void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
  25                                  struct sk_buff *skb)
  26 {
  27         struct ieee80211_local *local = hw_to_local(hw);
  28         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  29         int tmp;
  30
  31         skb->pkt_type = IEEE80211_TX_STATUS_MSG;
  32         skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
  33                        &local->skb_queue : &local->skb_queue_unreliable, skb);
  34         tmp = skb_queue_len(&local->skb_queue) +
  35                 skb_queue_len(&local->skb_queue_unreliable);
  36         while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
  37                (skb = skb_dequeue(&local->skb_queue_unreliable))) {
  38                 ieee80211_free_txskb(hw, skb);
  39                 tmp--;
  40                 I802_DEBUG_INC(local->tx_status_drop);
  41         }
  42         tasklet_schedule(&local->tasklet);
  43 }
  44 EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
  45
  46 static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
  47                                             struct sta_info *sta,
  48                                             struct sk_buff *skb)
  49 {
  50         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  51         struct ieee80211_hdr *hdr = (void *)skb->data;
  52         int ac;
  53
  54         if (info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
  55                            IEEE80211_TX_CTL_AMPDU)) {
  56                 ieee80211_free_txskb(&local->hw, skb);
  57                 return;
  58         }
  59
  60         /*
  61          * This skb 'survived' a round-trip through the driver, and
  62          * hopefully the driver didn't mangle it too badly. However,
  63          * we can definitely not rely on the control information
  64          * being correct. Clear it so we don't get junk there, and
  65          * indicate that it needs new processing, but must not be
  66          * modified/encrypted again.
  67          */
  68         memset(&info->control, 0, sizeof(info->control));
  69
  70         info->control.jiffies = jiffies;
  71         info->control.vif = &sta->sdata->vif;
  72         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
  73                        IEEE80211_TX_INTFL_RETRANSMISSION;
  74         info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
  75
  76         sta->status_stats.filtered++;
  77
  78         /*
  79          * Clear more-data bit on filtered frames, it might be set
  80          * but later frames might time out so it might have to be
  81          * clear again ... It's all rather unlikely (this frame
  82          * should time out first, right?) but let's not confuse
  83          * peers unnecessarily.
  84          */
  85         if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
  86                 hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);
  87
  88         if (ieee80211_is_data_qos(hdr->frame_control)) {
  89                 u8 *p = ieee80211_get_qos_ctl(hdr);
  90                 int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
  91
  92                 /*
  93                  * Clear EOSP if set, this could happen e.g.
  94                  * if an absence period (us being a P2P GO)
  95                  * shortens the SP.
  96                  */
  97                 if (*p & IEEE80211_QOS_CTL_EOSP)
  98                         *p &= ~IEEE80211_QOS_CTL_EOSP;
  99                 ac = ieee80211_ac_from_tid(tid);
 100         } else {
 101                 ac = IEEE80211_AC_BE;
 102         }
 103
 104         /*
 105          * Clear the TX filter mask for this STA when sending the next
 106          * packet. If the STA went to power save mode, this will happen
 107          * when it wakes up for the next time.
 108          */
 109         set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
 110         ieee80211_clear_fast_xmit(sta);
 111
 112         /*
 113          * This code races in the following way:
 114          *
 115          *  (1) STA sends frame indicating it will go to sleep and does so
 116          *  (2) hardware/firmware adds STA to filter list, passes frame up
 117          *  (3) hardware/firmware processes TX fifo and suppresses a frame
 118          *  (4) we get TX status before having processed the frame and
 119          *      knowing that the STA has gone to sleep.
 120          *
 121          * This is actually quite unlikely even when both those events are
 122          * processed from interrupts coming in quickly after one another or
 123          * even at the same time because we queue both TX status events and
 124          * RX frames to be processed by a tasklet and process them in the
 125          * same order that they were received or TX status last. Hence, there
 126          * is no race as long as the frame RX is processed before the next TX
 127          * status, which drivers can ensure, see below.
 128          *
 129          * Note that this can only happen if the hardware or firmware can
 130          * actually add STAs to the filter list, if this is done by the
 131          * driver in response to set_tim() (which will only reduce the race
 132          * this whole filtering tries to solve, not completely solve it)
 133          * this situation cannot happen.
 134          *
 135          * To completely solve this race drivers need to make sure that they
 136          *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
 137          *      functions and
 138          *  (b) always process RX events before TX status events if ordering
 139          *      can be unknown, for example with different interrupt status
 140          *      bits.
 141          *  (c) if PS mode transitions are manual (i.e. the flag
 142          *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
 143          *      changes before calling TX status events if ordering can be
 144          *      unknown.
 145          */
 146         if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
 147             skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
 148                 skb_queue_tail(&sta->tx_filtered[ac], skb);
 149                 sta_info_recalc_tim(sta);
 150
 151                 if (!timer_pending(&local->sta_cleanup))
 152                         mod_timer(&local->sta_cleanup,
 153                                   round_jiffies(jiffies +
 154                                                 STA_INFO_CLEANUP_INTERVAL));
 155                 return;
 156         }
 157
 158         if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
 159             !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
 160                 /* Software retry the packet once */
 161                 info->flags |= IEEE80211_TX_INTFL_RETRIED;
 162                 ieee80211_add_pending_skb(local, skb);
 163                 return;
 164         }
 165
 166         ps_dbg_ratelimited(sta->sdata,
 167                            "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
 168                            skb_queue_len(&sta->tx_filtered[ac]),
 169                            !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);
 170         ieee80211_free_txskb(&local->hw, skb);
 171 }
 172
 173 static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
 174 {
 175         struct tid_ampdu_tx *tid_tx;
 176
 177         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 178         if (!tid_tx || !tid_tx->bar_pending)
 179                 return;
 180
 181         tid_tx->bar_pending = false;
 182         ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);
 183 }
 184
 185 static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
 186 {
 187         struct ieee80211_mgmt *mgmt = (void *) skb->data;
 188         struct ieee80211_local *local = sta->local;
 189         struct ieee80211_sub_if_data *sdata = sta->sdata;
 190
 191         if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 192                 sta->status_stats.last_ack = jiffies;
 193
 194         if (ieee80211_is_data_qos(mgmt->frame_control)) {
 195                 struct ieee80211_hdr *hdr = (void *) skb->data;
 196                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 197                 u16 tid = qc[0] & 0xf;
 198
 199                 ieee80211_check_pending_bar(sta, hdr->addr1, tid);
 200         }
 201
 202         if (ieee80211_is_action(mgmt->frame_control) &&
 203             mgmt->u.action.category == WLAN_CATEGORY_HT &&
 204             mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
 205             ieee80211_sdata_running(sdata)) {
 206                 enum ieee80211_smps_mode smps_mode;
 207
 208                 switch (mgmt->u.action.u.ht_smps.smps_control) {
 209                 case WLAN_HT_SMPS_CONTROL_DYNAMIC:
 210                         smps_mode = IEEE80211_SMPS_DYNAMIC;
 211                         break;
 212                 case WLAN_HT_SMPS_CONTROL_STATIC:
 213                         smps_mode = IEEE80211_SMPS_STATIC;
 214                         break;
 215                 case WLAN_HT_SMPS_CONTROL_DISABLED:
 216                 default: /* shouldn't happen since we don't send that */
 217                         smps_mode = IEEE80211_SMPS_OFF;
 218                         break;
 219                 }
 220
 221                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 222                         /*
 223                          * This update looks racy, but isn't -- if we come
 224                          * here we've definitely got a station that we're
 225                          * talking to, and on a managed interface that can
 226                          * only be the AP. And the only other place updating
 227                          * this variable in managed mode is before association.
 228                          */
 229                         sdata->smps_mode = smps_mode;
 230                         ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
 231                 } else if (sdata->vif.type == NL80211_IFTYPE_AP ||
 232                            sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 233                         sta->known_smps_mode = smps_mode;
 234                 }
 235         }
 236 }
 237
 238 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
 239 {
 240         struct tid_ampdu_tx *tid_tx;
 241
 242         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 243         if (!tid_tx)
 244                 return;
 245
 246         tid_tx->failed_bar_ssn = ssn;
 247         tid_tx->bar_pending = true;
 248 }
 249
 250 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
 251 {
 252         int len = sizeof(struct ieee80211_radiotap_header);
 253
 254         /* IEEE80211_RADIOTAP_RATE rate */
 255         if (info->status.rates[0].idx >= 0 &&
 256             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 257                                              IEEE80211_TX_RC_VHT_MCS)))
 258                 len += 2;
 259
 260         /* IEEE80211_RADIOTAP_TX_FLAGS */
 261         len += 2;
 262
 263         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 264         len += 1;
 265
 266         /* IEEE80211_RADIOTAP_MCS
 267          * IEEE80211_RADIOTAP_VHT */
 268         if (info->status.rates[0].idx >= 0) {
 269                 if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
 270                         len += 3;
 271                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
 272                         len = ALIGN(len, 2) + 12;
 273         }
 274
 275         return len;
 276 }
 277
 278 static void
 279 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
 280                                  struct ieee80211_supported_band *sband,
 281                                  struct sk_buff *skb, int retry_count,
 282                                  int rtap_len, int shift)
 283 {
 284         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 285         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 286         struct ieee80211_radiotap_header *rthdr;
 287         unsigned char *pos;
 288         u16 txflags;
 289
 290         rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len);
 291
 292         memset(rthdr, 0, rtap_len);
 293         rthdr->it_len = cpu_to_le16(rtap_len);
 294         rthdr->it_present =
 295                 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
 296                             (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
 297         pos = (unsigned char *)(rthdr + 1);
 298
 299         /*
 300          * XXX: Once radiotap gets the bitmap reset thing the vendor
 301          *      extensions proposal contains, we can actually report
 302          *      the whole set of tries we did.
 303          */
 304
 305         /* IEEE80211_RADIOTAP_RATE */
 306         if (info->status.rates[0].idx >= 0 &&
 307             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 308                                              IEEE80211_TX_RC_VHT_MCS))) {
 309                 u16 rate;
 310
 311                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 312                 rate = sband->bitrates[info->status.rates[0].idx].bitrate;
 313                 *pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
 314                 /* padding for tx flags */
 315                 pos += 2;
 316         }
 317
 318         /* IEEE80211_RADIOTAP_TX_FLAGS */
 319         txflags = 0;
 320         if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
 321             !is_multicast_ether_addr(hdr->addr1))
 322                 txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
 323
 324         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
 325                 txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
 326         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
 327                 txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
 328
 329         put_unaligned_le16(txflags, pos);
 330         pos += 2;
 331
 332         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 333         /* for now report the total retry_count */
 334         *pos = retry_count;
 335         pos++;
 336
 337         if (info->status.rates[0].idx < 0)
 338                 return;
 339
 340         /* IEEE80211_RADIOTAP_MCS
 341          * IEEE80211_RADIOTAP_VHT */
 342         if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
 343                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 344                 pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
 345                          IEEE80211_RADIOTAP_MCS_HAVE_GI |
 346                          IEEE80211_RADIOTAP_MCS_HAVE_BW;
 347                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 348                         pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
 349                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 350                         pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
 351                 if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
 352                         pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 353                 pos[2] = info->status.rates[0].idx;
 354                 pos += 3;
 355         } else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
 356                 u16 known = local->hw.radiotap_vht_details &
 357                         (IEEE80211_RADIOTAP_VHT_KNOWN_GI |
 358                          IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
 359
 360                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 361
 362                 /* required alignment from rthdr */
 363                 pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
 364
 365                 /* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
 366                 put_unaligned_le16(known, pos);
 367                 pos += 2;
 368
 369                 /* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
 370                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 371                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 372                 pos++;
 373
 374                 /* u8 bandwidth */
 375                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 376                         *pos = 1;
 377                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
 378                         *pos = 4;
 379                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
 380                         *pos = 11;
 381                 else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
 382                         *pos = 0;
 383                 pos++;
 384
 385                 /* u8 mcs_nss[4] */
 386                 *pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
 387                         ieee80211_rate_get_vht_nss(&info->status.rates[0]);
 388                 pos += 4;
 389
 390                 /* u8 coding */
 391                 pos++;
 392                 /* u8 group_id */
 393                 pos++;
 394                 /* u16 partial_aid */
 395                 pos += 2;
 396         }
 397 }
 398
 399 /*
 400  * Handles the tx for TDLS teardown frames.
 401  * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
 402  */
 403 static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
 404                                         struct ieee80211_sub_if_data *sdata,
 405                                         struct sk_buff *skb, u32 flags)
 406 {
 407         struct sk_buff *teardown_skb;
 408         struct sk_buff *orig_teardown_skb;
 409         bool is_teardown = false;
 410
 411         /* Get the teardown data we need and free the lock */
 412         spin_lock(&sdata->u.mgd.teardown_lock);
 413         teardown_skb = sdata->u.mgd.teardown_skb;
 414         orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
 415         if ((skb == orig_teardown_skb) && teardown_skb) {
 416                 sdata->u.mgd.teardown_skb = NULL;
 417                 sdata->u.mgd.orig_teardown_skb = NULL;
 418                 is_teardown = true;
 419         }
 420         spin_unlock(&sdata->u.mgd.teardown_lock);
 421
 422         if (is_teardown) {
 423                 /* This mechanism relies on being able to get ACKs */
 424                 WARN_ON(!ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS));
 425
 426                 /* Check if peer has ACKed */
 427                 if (flags & IEEE80211_TX_STAT_ACK) {
 428                         dev_kfree_skb_any(teardown_skb);
 429                 } else {
 430                         tdls_dbg(sdata,
 431                                  "TDLS Resending teardown through AP\n");
 432
 433                         ieee80211_subif_start_xmit(teardown_skb, skb->dev);
 434                 }
 435         }
 436 }
 437
 438 static struct ieee80211_sub_if_data *
 439 ieee80211_sdata_from_skb(struct ieee80211_local *local, struct sk_buff *skb)
 440 {
 441         struct ieee80211_sub_if_data *sdata;
 442
 443         if (skb->dev) {
 444                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 445                         if (!sdata->dev)
 446                                 continue;
 447
 448                         if (skb->dev == sdata->dev)
 449                                 return sdata;
 450                 }
 451
 452                 return NULL;
 453         }
 454
 455         return rcu_dereference(local->p2p_sdata);
 456 }
 457
 458 static void ieee80211_report_ack_skb(struct ieee80211_local *local,
 459                                      struct ieee80211_tx_info *info,
 460                                      bool acked, bool dropped)
 461 {
 462         struct sk_buff *skb;
 463         unsigned long flags;
 464
 465         spin_lock_irqsave(&local->ack_status_lock, flags);
 466         skb = idr_remove(&local->ack_status_frames, info->ack_frame_id);
 467         spin_unlock_irqrestore(&local->ack_status_lock, flags);
 468
 469         if (!skb)
 470                 return;
 471
 472         if (dropped) {
 473                 dev_kfree_skb_any(skb);
 474                 return;
 475         }
 476
 477         if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {
 478                 u64 cookie = IEEE80211_SKB_CB(skb)->ack.cookie;
 479                 struct ieee80211_sub_if_data *sdata;
 480                 struct ieee80211_hdr *hdr = (void *)skb->data;
 481
 482                 rcu_read_lock();
 483                 sdata = ieee80211_sdata_from_skb(local, skb);
 484                 if (sdata) {
 485                         if (ieee80211_is_nullfunc(hdr->frame_control) ||
 486                             ieee80211_is_qos_nullfunc(hdr->frame_control))
 487                                 cfg80211_probe_status(sdata->dev, hdr->addr1,
 488                                                       cookie, acked,
 489                                                       GFP_ATOMIC);
 490                         else
 491                                 cfg80211_mgmt_tx_status(&sdata->wdev, cookie,
 492                                                         skb->data, skb->len,
 493                                                         acked, GFP_ATOMIC);
 494                 }
 495                 rcu_read_unlock();
 496
 497                 dev_kfree_skb_any(skb);
 498         } else {
 499                 /* consumes skb */
 500                 skb_complete_wifi_ack(skb, acked);
 501         }
 502 }
 503
 504 static void ieee80211_report_used_skb(struct ieee80211_local *local,
 505                                       struct sk_buff *skb, bool dropped)
 506 {
 507         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 508         struct ieee80211_hdr *hdr = (void *)skb->data;
 509         bool acked = info->flags & IEEE80211_TX_STAT_ACK;
 510
 511         if (dropped)
 512                 acked = false;
 513
 514         if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
 515                 struct ieee80211_sub_if_data *sdata;
 516
 517                 rcu_read_lock();
 518
 519                 sdata = ieee80211_sdata_from_skb(local, skb);
 520
 521                 if (!sdata) {
 522                         skb->dev = NULL;
 523                 } else {
 524                         unsigned int hdr_size =
 525                                 ieee80211_hdrlen(hdr->frame_control);
 526
 527                         /* Check to see if packet is a TDLS teardown packet */
 528                         if (ieee80211_is_data(hdr->frame_control) &&
 529                             (ieee80211_get_tdls_action(skb, hdr_size) ==
 530                              WLAN_TDLS_TEARDOWN))
 531                                 ieee80211_tdls_td_tx_handle(local, sdata, skb,
 532                                                             info->flags);
 533                         else
 534                                 ieee80211_mgd_conn_tx_status(sdata,
 535                                                              hdr->frame_control,
 536                                                              acked);
 537                 }
 538
 539                 rcu_read_unlock();
 540         } else if (info->ack_frame_id) {
 541                 ieee80211_report_ack_skb(local, info, acked, dropped);
 542         }
 543
 544         if (!dropped && skb->destructor) {
 545                 skb->wifi_acked_valid = 1;
 546                 skb->wifi_acked = acked;
 547         }
 548 }
 549
 550 /*
 551  * Use a static threshold for now, best value to be determined
 552  * by testing ...
 553  * Should it depend on:
 554  *  - on # of retransmissions
 555  *  - current throughput (higher value for higher tpt)?
 556  */
 557 #define STA_LOST_PKT_THRESHOLD  50
 558 #define STA_LOST_TDLS_PKT_THRESHOLD     10
 559 #define STA_LOST_TDLS_PKT_TIME          (10*HZ) /* 10secs since last ACK */
 560
 561 static void ieee80211_lost_packet(struct sta_info *sta,
 562                                   struct ieee80211_tx_info *info)
 563 {
 564         /* If driver relies on its own algorithm for station kickout, skip
 565          * mac80211 packet loss mechanism.
 566          */
 567         if (ieee80211_hw_check(&sta->local->hw, REPORTS_LOW_ACK))
 568                 return;
 569
 570         /* This packet was aggregated but doesn't carry status info */
 571         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 572             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 573                 return;
 574
 575         sta->status_stats.lost_packets++;
 576         if (!sta->sta.tdls &&
 577             sta->status_stats.lost_packets < STA_LOST_PKT_THRESHOLD)
 578                 return;
 579
 580         /*
 581          * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
 582          * of the last packets were lost, and that no ACK was received in the
 583          * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
 584          * mechanism.
 585          */
 586         if (sta->sta.tdls &&
 587             (sta->status_stats.lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||
 588              time_before(jiffies,
 589                          sta->status_stats.last_tdls_pkt_time +
 590                          STA_LOST_TDLS_PKT_TIME)))
 591                 return;
 592
 593         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 594                                     sta->status_stats.lost_packets, GFP_ATOMIC);
 595         sta->status_stats.lost_packets = 0;
 596 }
 597
 598 static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
 599                                   struct ieee80211_tx_info *info,
 600                                   int *retry_count)
 601 {
 602         int rates_idx = -1;
 603         int count = -1;
 604         int i;
 605
 606         for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 607                 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 608                     !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
 609                         /* just the first aggr frame carry status info */
 610                         info->status.rates[i].idx = -1;
 611                         info->status.rates[i].count = 0;
 612                         break;
 613                 } else if (info->status.rates[i].idx < 0) {
 614                         break;
 615                 } else if (i >= hw->max_report_rates) {
 616                         /* the HW cannot have attempted that rate */
 617                         info->status.rates[i].idx = -1;
 618                         info->status.rates[i].count = 0;
 619                         break;
 620                 }
 621
 622                 count += info->status.rates[i].count;
 623         }
 624         rates_idx = i - 1;
 625
 626         if (count < 0)
 627                 count = 0;
 628
 629         *retry_count = count;
 630         return rates_idx;
 631 }
 632
 633 void ieee80211_tx_status_noskb(struct ieee80211_hw *hw,
 634                                struct ieee80211_sta *pubsta,
 635                                struct ieee80211_tx_info *info)
 636 {
 637         struct ieee80211_local *local = hw_to_local(hw);
 638         struct ieee80211_supported_band *sband;
 639         int retry_count;
 640         bool acked, noack_success;
 641
 642         ieee80211_tx_get_rates(hw, info, &retry_count);
 643
 644         sband = hw->wiphy->bands[info->band];
 645
 646         acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 647         noack_success = !!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED);
 648
 649         if (pubsta) {
 650                 struct sta_info *sta;
 651
 652                 sta = container_of(pubsta, struct sta_info, sta);
 653
 654                 if (!acked)
 655                         sta->status_stats.retry_failed++;
 656                 sta->status_stats.retry_count += retry_count;
 657
 658                 if (acked) {
 659                         sta->status_stats.last_ack = jiffies;
 660
 661                         if (sta->status_stats.lost_packets)
 662                                 sta->status_stats.lost_packets = 0;
 663
 664                         /* Track when last TDLS packet was ACKed */
 665                         if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 666                                 sta->status_stats.last_tdls_pkt_time = jiffies;
 667                 } else {
 668                         ieee80211_lost_packet(sta, info);
 669                 }
 670
 671                 rate_control_tx_status_noskb(local, sband, sta, info);
 672         }
 673
 674         if (acked || noack_success) {
 675                 I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 676                 if (!pubsta)
 677                         I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 678                 if (retry_count > 0)
 679                         I802_DEBUG_INC(local->dot11RetryCount);
 680                 if (retry_count > 1)
 681                         I802_DEBUG_INC(local->dot11MultipleRetryCount);
 682         } else {
 683                 I802_DEBUG_INC(local->dot11FailedCount);
 684         }
 685 }
 686 EXPORT_SYMBOL(ieee80211_tx_status_noskb);
 687
 688 void ieee80211_tx_monitor(struct ieee80211_local *local, struct sk_buff *skb,
 689                           struct ieee80211_supported_band *sband,
 690                           int retry_count, int shift, bool send_to_cooked)
 691 {
 692         struct sk_buff *skb2;
 693         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 694         struct ieee80211_sub_if_data *sdata;
 695         struct net_device *prev_dev = NULL;
 696         int rtap_len;
 697
 698         /* send frame to monitor interfaces now */
 699         rtap_len = ieee80211_tx_radiotap_len(info);
 700         if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
 701                 pr_err("ieee80211_tx_status: headroom too small\n");
 702                 dev_kfree_skb(skb);
 703                 return;
 704         }
 705         ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
 706                                          rtap_len, shift);
 707
 708         /* XXX: is this sufficient for BPF? */
 709         skb_reset_mac_header(skb);
 710         skb->ip_summed = CHECKSUM_UNNECESSARY;
 711         skb->pkt_type = PACKET_OTHERHOST;
 712         skb->protocol = htons(ETH_P_802_2);
 713         memset(skb->cb, 0, sizeof(skb->cb));
 714
 715         rcu_read_lock();
 716         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 717                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
 718                         if (!ieee80211_sdata_running(sdata))
 719                                 continue;
 720
 721                         if ((sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES) &&
 722                             !send_to_cooked)
 723                                 continue;
 724
 725                         if (prev_dev) {
 726                                 skb2 = skb_clone(skb, GFP_ATOMIC);
 727                                 if (skb2) {
 728                                         skb2->dev = prev_dev;
 729                                         netif_rx(skb2);
 730                                 }
 731                         }
 732
 733                         prev_dev = sdata->dev;
 734                 }
 735         }
 736         if (prev_dev) {
 737                 skb->dev = prev_dev;
 738                 netif_rx(skb);
 739                 skb = NULL;
 740         }
 741         rcu_read_unlock();
 742         dev_kfree_skb(skb);
 743 }
 744
 745 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
 746 {
 747         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 748         struct ieee80211_local *local = hw_to_local(hw);
 749         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 750         __le16 fc;
 751         struct ieee80211_supported_band *sband;
 752         struct rhlist_head *tmp;
 753         struct sta_info *sta;
 754         int retry_count;
 755         int rates_idx;
 756         bool send_to_cooked;
 757         bool acked;
 758         struct ieee80211_bar *bar;
 759         int shift = 0;
 760         int tid = IEEE80211_NUM_TIDS;
 761
 762         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 763
 764         rcu_read_lock();
 765
 766         sband = local->hw.wiphy->bands[info->band];
 767         fc = hdr->frame_control;
 768
 769         for_each_sta_info(local, hdr->addr1, sta, tmp) {
 770                 /* skip wrong virtual interface */
 771                 if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
 772                         continue;
 773
 774                 shift = ieee80211_vif_get_shift(&sta->sdata->vif);
 775
 776                 if (info->flags & IEEE80211_TX_STATUS_EOSP)
 777                         clear_sta_flag(sta, WLAN_STA_SP);
 778
 779                 acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 780
 781                 /* mesh Peer Service Period support */
 782                 if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
 783                     ieee80211_is_data_qos(fc))
 784                         ieee80211_mpsp_trigger_process(
 785                                 ieee80211_get_qos_ctl(hdr), sta, true, acked);
 786
 787                 if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
 788                         /*
 789                          * The STA is in power save mode, so assume
 790                          * that this TX packet failed because of that.
 791                          */
 792                         ieee80211_handle_filtered_frame(local, sta, skb);
 793                         rcu_read_unlock();
 794                         return;
 795                 }
 796
 797                 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL) &&
 798                     (ieee80211_is_data(hdr->frame_control)) &&
 799                     (rates_idx != -1))
 800                         sta->tx_stats.last_rate =
 801                                 info->status.rates[rates_idx];
 802
 803                 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
 804                     (ieee80211_is_data_qos(fc))) {
 805                         u16 ssn;
 806                         u8 *qc;
 807
 808                         qc = ieee80211_get_qos_ctl(hdr);
 809                         tid = qc[0] & 0xf;
 810                         ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
 811                                                 & IEEE80211_SCTL_SEQ);
 812                         ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
 813                                            tid, ssn);
 814                 } else if (ieee80211_is_data_qos(fc)) {
 815                         u8 *qc = ieee80211_get_qos_ctl(hdr);
 816
 817                         tid = qc[0] & 0xf;
 818                 }
 819
 820                 if (!acked && ieee80211_is_back_req(fc)) {
 821                         u16 control;
 822
 823                         /*
 824                          * BAR failed, store the last SSN and retry sending
 825                          * the BAR when the next unicast transmission on the
 826                          * same TID succeeds.
 827                          */
 828                         bar = (struct ieee80211_bar *) skb->data;
 829                         control = le16_to_cpu(bar->control);
 830                         if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
 831                                 u16 ssn = le16_to_cpu(bar->start_seq_num);
 832
 833                                 tid = (control &
 834                                        IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
 835                                       IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
 836
 837                                 ieee80211_set_bar_pending(sta, tid, ssn);
 838                         }
 839                 }
 840
 841                 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
 842                         ieee80211_handle_filtered_frame(local, sta, skb);
 843                         rcu_read_unlock();
 844                         return;
 845                 } else {
 846                         if (!acked)
 847                                 sta->status_stats.retry_failed++;
 848                         sta->status_stats.retry_count += retry_count;
 849
 850                         if (ieee80211_is_data_present(fc)) {
 851                                 if (!acked)
 852                                         sta->status_stats.msdu_failed[tid]++;
 853
 854                                 sta->status_stats.msdu_retries[tid] +=
 855                                         retry_count;
 856                         }
 857                 }
 858
 859                 rate_control_tx_status(local, sband, sta, skb);
 860                 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
 861                         ieee80211s_update_metric(local, sta, skb);
 862
 863                 if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
 864                         ieee80211_frame_acked(sta, skb);
 865
 866                 if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
 867                     ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 868                         ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
 869                                                 acked, info->status.tx_time);
 870
 871                 if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
 872                         if (info->flags & IEEE80211_TX_STAT_ACK) {
 873                                 if (sta->status_stats.lost_packets)
 874                                         sta->status_stats.lost_packets = 0;
 875
 876                                 /* Track when last TDLS packet was ACKed */
 877                                 if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 878                                         sta->status_stats.last_tdls_pkt_time =
 879                                                 jiffies;
 880                         } else {
 881                                 ieee80211_lost_packet(sta, info);
 882                         }
 883                 }
 884         }
 885
 886         rcu_read_unlock();
 887
 888         ieee80211_led_tx(local);
 889
 890         /* SNMP counters
 891          * Fragments are passed to low-level drivers as separate skbs, so these
 892          * are actually fragments, not frames. Update frame counters only for
 893          * the first fragment of the frame. */
 894         if ((info->flags & IEEE80211_TX_STAT_ACK) ||
 895             (info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED)) {
 896                 if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
 897                         I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 898                         if (is_multicast_ether_addr(ieee80211_get_DA(hdr)))
 899                                 I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 900                         if (retry_count > 0)
 901                                 I802_DEBUG_INC(local->dot11RetryCount);
 902                         if (retry_count > 1)
 903                                 I802_DEBUG_INC(local->dot11MultipleRetryCount);
 904                 }
 905
 906                 /* This counter shall be incremented for an acknowledged MPDU
 907                  * with an individual address in the address 1 field or an MPDU
 908                  * with a multicast address in the address 1 field of type Data
 909                  * or Management. */
 910                 if (!is_multicast_ether_addr(hdr->addr1) ||
 911                     ieee80211_is_data(fc) ||
 912                     ieee80211_is_mgmt(fc))
 913                         I802_DEBUG_INC(local->dot11TransmittedFragmentCount);
 914         } else {
 915                 if (ieee80211_is_first_frag(hdr->seq_ctrl))
 916                         I802_DEBUG_INC(local->dot11FailedCount);
 917         }
 918
 919         if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
 920             ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS) &&
 921             !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
 922             local->ps_sdata && !(local->scanning)) {
 923                 if (info->flags & IEEE80211_TX_STAT_ACK) {
 924                         local->ps_sdata->u.mgd.flags |=
 925                                         IEEE80211_STA_NULLFUNC_ACKED;
 926                 } else
 927                         mod_timer(&local->dynamic_ps_timer, jiffies +
 928                                         msecs_to_jiffies(10));
 929         }
 930
 931         ieee80211_report_used_skb(local, skb, false);
 932
 933         /* this was a transmitted frame, but now we want to reuse it */
 934         skb_orphan(skb);
 935
 936         /* Need to make a copy before skb->cb gets cleared */
 937         send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
 938                          !(ieee80211_is_data(fc));
 939
 940         /*
 941          * This is a bit racy but we can avoid a lot of work
 942          * with this test...
 943          */
 944         if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
 945                 dev_kfree_skb(skb);
 946                 return;
 947         }
 948
 949         /* send to monitor interfaces */
 950         ieee80211_tx_monitor(local, skb, sband, retry_count, shift, send_to_cooked);
 951 }
 952 EXPORT_SYMBOL(ieee80211_tx_status);
 953
 954 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
 955 {
 956         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 957         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 958                                     num_packets, GFP_ATOMIC);
 959 }
 960 EXPORT_SYMBOL(ieee80211_report_low_ack);
 961
 962 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
 963 {
 964         struct ieee80211_local *local = hw_to_local(hw);
 965
 966         ieee80211_report_used_skb(local, skb, true);
 967         dev_kfree_skb_any(skb);
 968 }
 969 EXPORT_SYMBOL(ieee80211_free_txskb);
 970
 971 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
 972                               struct sk_buff_head *skbs)
 973 {
 974         struct sk_buff *skb;
 975
 976         while ((skb = __skb_dequeue(skbs)))
 977                 ieee80211_free_txskb(hw, skb);
 978 }