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         /*
  55          * This skb 'survived' a round-trip through the driver, and
  56          * hopefully the driver didn't mangle it too badly. However,
  57          * we can definitely not rely on the control information
  58          * being correct. Clear it so we don't get junk there, and
  59          * indicate that it needs new processing, but must not be
  60          * modified/encrypted again.
  61          */
  62         memset(&info->control, 0, sizeof(info->control));
  63
  64         info->control.jiffies = jiffies;
  65         info->control.vif = &sta->sdata->vif;
  66         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
  67                        IEEE80211_TX_INTFL_RETRANSMISSION;
  68         info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
  69
  70         sta->tx_filtered_count++;
  71
  72         /*
  73          * Clear more-data bit on filtered frames, it might be set
  74          * but later frames might time out so it might have to be
  75          * clear again ... It's all rather unlikely (this frame
  76          * should time out first, right?) but let's not confuse
  77          * peers unnecessarily.
  78          */
  79         if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
  80                 hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);
  81
  82         if (ieee80211_is_data_qos(hdr->frame_control)) {
  83                 u8 *p = ieee80211_get_qos_ctl(hdr);
  84                 int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
  85
  86                 /*
  87                  * Clear EOSP if set, this could happen e.g.
  88                  * if an absence period (us being a P2P GO)
  89                  * shortens the SP.
  90                  */
  91                 if (*p & IEEE80211_QOS_CTL_EOSP)
  92                         *p &= ~IEEE80211_QOS_CTL_EOSP;
  93                 ac = ieee802_1d_to_ac[tid & 7];
  94         } else {
  95                 ac = IEEE80211_AC_BE;
  96         }
  97
  98         /*
  99          * Clear the TX filter mask for this STA when sending the next
 100          * packet. If the STA went to power save mode, this will happen
 101          * when it wakes up for the next time.
 102          */
 103         set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
 104         ieee80211_clear_fast_xmit(sta);
 105
 106         /*
 107          * This code races in the following way:
 108          *
 109          *  (1) STA sends frame indicating it will go to sleep and does so
 110          *  (2) hardware/firmware adds STA to filter list, passes frame up
 111          *  (3) hardware/firmware processes TX fifo and suppresses a frame
 112          *  (4) we get TX status before having processed the frame and
 113          *      knowing that the STA has gone to sleep.
 114          *
 115          * This is actually quite unlikely even when both those events are
 116          * processed from interrupts coming in quickly after one another or
 117          * even at the same time because we queue both TX status events and
 118          * RX frames to be processed by a tasklet and process them in the
 119          * same order that they were received or TX status last. Hence, there
 120          * is no race as long as the frame RX is processed before the next TX
 121          * status, which drivers can ensure, see below.
 122          *
 123          * Note that this can only happen if the hardware or firmware can
 124          * actually add STAs to the filter list, if this is done by the
 125          * driver in response to set_tim() (which will only reduce the race
 126          * this whole filtering tries to solve, not completely solve it)
 127          * this situation cannot happen.
 128          *
 129          * To completely solve this race drivers need to make sure that they
 130          *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
 131          *      functions and
 132          *  (b) always process RX events before TX status events if ordering
 133          *      can be unknown, for example with different interrupt status
 134          *      bits.
 135          *  (c) if PS mode transitions are manual (i.e. the flag
 136          *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
 137          *      changes before calling TX status events if ordering can be
 138          *      unknown.
 139          */
 140         if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
 141             skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
 142                 skb_queue_tail(&sta->tx_filtered[ac], skb);
 143                 sta_info_recalc_tim(sta);
 144
 145                 if (!timer_pending(&local->sta_cleanup))
 146                         mod_timer(&local->sta_cleanup,
 147                                   round_jiffies(jiffies +
 148                                                 STA_INFO_CLEANUP_INTERVAL));
 149                 return;
 150         }
 151
 152         if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
 153             !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
 154                 /* Software retry the packet once */
 155                 info->flags |= IEEE80211_TX_INTFL_RETRIED;
 156                 ieee80211_add_pending_skb(local, skb);
 157                 return;
 158         }
 159
 160         ps_dbg_ratelimited(sta->sdata,
 161                            "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
 162                            skb_queue_len(&sta->tx_filtered[ac]),
 163                            !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);
 164         ieee80211_free_txskb(&local->hw, skb);
 165 }
 166
 167 static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
 168 {
 169         struct tid_ampdu_tx *tid_tx;
 170
 171         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 172         if (!tid_tx || !tid_tx->bar_pending)
 173                 return;
 174
 175         tid_tx->bar_pending = false;
 176         ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);
 177 }
 178
 179 static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
 180 {
 181         struct ieee80211_mgmt *mgmt = (void *) skb->data;
 182         struct ieee80211_local *local = sta->local;
 183         struct ieee80211_sub_if_data *sdata = sta->sdata;
 184
 185         if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 186                 sta->last_rx = jiffies;
 187
 188         if (ieee80211_is_data_qos(mgmt->frame_control)) {
 189                 struct ieee80211_hdr *hdr = (void *) skb->data;
 190                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 191                 u16 tid = qc[0] & 0xf;
 192
 193                 ieee80211_check_pending_bar(sta, hdr->addr1, tid);
 194         }
 195
 196         if (ieee80211_is_action(mgmt->frame_control) &&
 197             mgmt->u.action.category == WLAN_CATEGORY_HT &&
 198             mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
 199             ieee80211_sdata_running(sdata)) {
 200                 enum ieee80211_smps_mode smps_mode;
 201
 202                 switch (mgmt->u.action.u.ht_smps.smps_control) {
 203                 case WLAN_HT_SMPS_CONTROL_DYNAMIC:
 204                         smps_mode = IEEE80211_SMPS_DYNAMIC;
 205                         break;
 206                 case WLAN_HT_SMPS_CONTROL_STATIC:
 207                         smps_mode = IEEE80211_SMPS_STATIC;
 208                         break;
 209                 case WLAN_HT_SMPS_CONTROL_DISABLED:
 210                 default: /* shouldn't happen since we don't send that */
 211                         smps_mode = IEEE80211_SMPS_OFF;
 212                         break;
 213                 }
 214
 215                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 216                         /*
 217                          * This update looks racy, but isn't -- if we come
 218                          * here we've definitely got a station that we're
 219                          * talking to, and on a managed interface that can
 220                          * only be the AP. And the only other place updating
 221                          * this variable in managed mode is before association.
 222                          */
 223                         sdata->smps_mode = smps_mode;
 224                         ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
 225                 } else if (sdata->vif.type == NL80211_IFTYPE_AP ||
 226                            sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 227                         sta->known_smps_mode = smps_mode;
 228                 }
 229         }
 230 }
 231
 232 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
 233 {
 234         struct tid_ampdu_tx *tid_tx;
 235
 236         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 237         if (!tid_tx)
 238                 return;
 239
 240         tid_tx->failed_bar_ssn = ssn;
 241         tid_tx->bar_pending = true;
 242 }
 243
 244 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
 245 {
 246         int len = sizeof(struct ieee80211_radiotap_header);
 247
 248         /* IEEE80211_RADIOTAP_RATE rate */
 249         if (info->status.rates[0].idx >= 0 &&
 250             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 251                                              IEEE80211_TX_RC_VHT_MCS)))
 252                 len += 2;
 253
 254         /* IEEE80211_RADIOTAP_TX_FLAGS */
 255         len += 2;
 256
 257         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 258         len += 1;
 259
 260         /* IEEE80211_RADIOTAP_MCS
 261          * IEEE80211_RADIOTAP_VHT */
 262         if (info->status.rates[0].idx >= 0) {
 263                 if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
 264                         len += 3;
 265                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
 266                         len = ALIGN(len, 2) + 12;
 267         }
 268
 269         return len;
 270 }
 271
 272 static void
 273 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
 274                                  struct ieee80211_supported_band *sband,
 275                                  struct sk_buff *skb, int retry_count,
 276                                  int rtap_len, int shift)
 277 {
 278         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 279         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 280         struct ieee80211_radiotap_header *rthdr;
 281         unsigned char *pos;
 282         u16 txflags;
 283
 284         rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len);
 285
 286         memset(rthdr, 0, rtap_len);
 287         rthdr->it_len = cpu_to_le16(rtap_len);
 288         rthdr->it_present =
 289                 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
 290                             (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
 291         pos = (unsigned char *)(rthdr + 1);
 292
 293         /*
 294          * XXX: Once radiotap gets the bitmap reset thing the vendor
 295          *      extensions proposal contains, we can actually report
 296          *      the whole set of tries we did.
 297          */
 298
 299         /* IEEE80211_RADIOTAP_RATE */
 300         if (info->status.rates[0].idx >= 0 &&
 301             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 302                                              IEEE80211_TX_RC_VHT_MCS))) {
 303                 u16 rate;
 304
 305                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 306                 rate = sband->bitrates[info->status.rates[0].idx].bitrate;
 307                 *pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
 308                 /* padding for tx flags */
 309                 pos += 2;
 310         }
 311
 312         /* IEEE80211_RADIOTAP_TX_FLAGS */
 313         txflags = 0;
 314         if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
 315             !is_multicast_ether_addr(hdr->addr1))
 316                 txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
 317
 318         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
 319                 txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
 320         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
 321                 txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
 322
 323         put_unaligned_le16(txflags, pos);
 324         pos += 2;
 325
 326         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 327         /* for now report the total retry_count */
 328         *pos = retry_count;
 329         pos++;
 330
 331         if (info->status.rates[0].idx < 0)
 332                 return;
 333
 334         /* IEEE80211_RADIOTAP_MCS
 335          * IEEE80211_RADIOTAP_VHT */
 336         if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
 337                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 338                 pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
 339                          IEEE80211_RADIOTAP_MCS_HAVE_GI |
 340                          IEEE80211_RADIOTAP_MCS_HAVE_BW;
 341                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 342                         pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
 343                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 344                         pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
 345                 if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
 346                         pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 347                 pos[2] = info->status.rates[0].idx;
 348                 pos += 3;
 349         } else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
 350                 u16 known = local->hw.radiotap_vht_details &
 351                         (IEEE80211_RADIOTAP_VHT_KNOWN_GI |
 352                          IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
 353
 354                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 355
 356                 /* required alignment from rthdr */
 357                 pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
 358
 359                 /* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
 360                 put_unaligned_le16(known, pos);
 361                 pos += 2;
 362
 363                 /* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
 364                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 365                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 366                 pos++;
 367
 368                 /* u8 bandwidth */
 369                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 370                         *pos = 1;
 371                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
 372                         *pos = 4;
 373                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
 374                         *pos = 11;
 375                 else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
 376                         *pos = 0;
 377                 pos++;
 378
 379                 /* u8 mcs_nss[4] */
 380                 *pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
 381                         ieee80211_rate_get_vht_nss(&info->status.rates[0]);
 382                 pos += 4;
 383
 384                 /* u8 coding */
 385                 pos++;
 386                 /* u8 group_id */
 387                 pos++;
 388                 /* u16 partial_aid */
 389                 pos += 2;
 390         }
 391 }
 392
 393 /*
 394  * Handles the tx for TDLS teardown frames.
 395  * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
 396  */
 397 static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
 398                                         struct ieee80211_sub_if_data *sdata,
 399                                         struct sk_buff *skb, u32 flags)
 400 {
 401         struct sk_buff *teardown_skb;
 402         struct sk_buff *orig_teardown_skb;
 403         bool is_teardown = false;
 404
 405         /* Get the teardown data we need and free the lock */
 406         spin_lock(&sdata->u.mgd.teardown_lock);
 407         teardown_skb = sdata->u.mgd.teardown_skb;
 408         orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
 409         if ((skb == orig_teardown_skb) && teardown_skb) {
 410                 sdata->u.mgd.teardown_skb = NULL;
 411                 sdata->u.mgd.orig_teardown_skb = NULL;
 412                 is_teardown = true;
 413         }
 414         spin_unlock(&sdata->u.mgd.teardown_lock);
 415
 416         if (is_teardown) {
 417                 /* This mechanism relies on being able to get ACKs */
 418                 WARN_ON(!ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS));
 419
 420                 /* Check if peer has ACKed */
 421                 if (flags & IEEE80211_TX_STAT_ACK) {
 422                         dev_kfree_skb_any(teardown_skb);
 423                 } else {
 424                         tdls_dbg(sdata,
 425                                  "TDLS Resending teardown through AP\n");
 426
 427                         ieee80211_subif_start_xmit(teardown_skb, skb->dev);
 428                 }
 429         }
 430 }
 431
 432 static struct ieee80211_sub_if_data *
 433 ieee80211_sdata_from_skb(struct ieee80211_local *local, struct sk_buff *skb)
 434 {
 435         struct ieee80211_sub_if_data *sdata;
 436
 437         if (skb->dev) {
 438                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 439                         if (!sdata->dev)
 440                                 continue;
 441
 442                         if (skb->dev == sdata->dev)
 443                                 return sdata;
 444                 }
 445
 446                 return NULL;
 447         }
 448
 449         return rcu_dereference(local->p2p_sdata);
 450 }
 451
 452 static void ieee80211_report_ack_skb(struct ieee80211_local *local,
 453                                      struct ieee80211_tx_info *info,
 454                                      bool acked, bool dropped)
 455 {
 456         struct sk_buff *skb;
 457         unsigned long flags;
 458
 459         spin_lock_irqsave(&local->ack_status_lock, flags);
 460         skb = idr_find(&local->ack_status_frames, info->ack_frame_id);
 461         if (skb)
 462                 idr_remove(&local->ack_status_frames, info->ack_frame_id);
 463         spin_unlock_irqrestore(&local->ack_status_lock, flags);
 464
 465         if (!skb)
 466                 return;
 467
 468         if (dropped) {
 469                 dev_kfree_skb_any(skb);
 470                 return;
 471         }
 472
 473         if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {
 474                 u64 cookie = IEEE80211_SKB_CB(skb)->ack.cookie;
 475                 struct ieee80211_sub_if_data *sdata;
 476                 struct ieee80211_hdr *hdr = (void *)skb->data;
 477
 478                 rcu_read_lock();
 479                 sdata = ieee80211_sdata_from_skb(local, skb);
 480                 if (sdata) {
 481                         if (ieee80211_is_nullfunc(hdr->frame_control) ||
 482                             ieee80211_is_qos_nullfunc(hdr->frame_control))
 483                                 cfg80211_probe_status(sdata->dev, hdr->addr1,
 484                                                       cookie, acked,
 485                                                       GFP_ATOMIC);
 486                         else
 487                                 cfg80211_mgmt_tx_status(&sdata->wdev, cookie,
 488                                                         skb->data, skb->len,
 489                                                         acked, GFP_ATOMIC);
 490                 }
 491                 rcu_read_unlock();
 492
 493                 dev_kfree_skb_any(skb);
 494         } else {
 495                 /* consumes skb */
 496                 skb_complete_wifi_ack(skb, acked);
 497         }
 498 }
 499
 500 static void ieee80211_report_used_skb(struct ieee80211_local *local,
 501                                       struct sk_buff *skb, bool dropped)
 502 {
 503         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 504         struct ieee80211_hdr *hdr = (void *)skb->data;
 505         bool acked = info->flags & IEEE80211_TX_STAT_ACK;
 506
 507         if (dropped)
 508                 acked = false;
 509
 510         if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
 511                 struct ieee80211_sub_if_data *sdata;
 512
 513                 rcu_read_lock();
 514
 515                 sdata = ieee80211_sdata_from_skb(local, skb);
 516
 517                 if (!sdata) {
 518                         skb->dev = NULL;
 519                 } else {
 520                         unsigned int hdr_size =
 521                                 ieee80211_hdrlen(hdr->frame_control);
 522
 523                         /* Check to see if packet is a TDLS teardown packet */
 524                         if (ieee80211_is_data(hdr->frame_control) &&
 525                             (ieee80211_get_tdls_action(skb, hdr_size) ==
 526                              WLAN_TDLS_TEARDOWN))
 527                                 ieee80211_tdls_td_tx_handle(local, sdata, skb,
 528                                                             info->flags);
 529                         else
 530                                 ieee80211_mgd_conn_tx_status(sdata,
 531                                                              hdr->frame_control,
 532                                                              acked);
 533                 }
 534
 535                 rcu_read_unlock();
 536         } else if (info->ack_frame_id) {
 537                 ieee80211_report_ack_skb(local, info, acked, dropped);
 538         }
 539 }
 540
 541 /*
 542  * Use a static threshold for now, best value to be determined
 543  * by testing ...
 544  * Should it depend on:
 545  *  - on # of retransmissions
 546  *  - current throughput (higher value for higher tpt)?
 547  */
 548 #define STA_LOST_PKT_THRESHOLD  50
 549 #define STA_LOST_TDLS_PKT_THRESHOLD     10
 550 #define STA_LOST_TDLS_PKT_TIME          (10*HZ) /* 10secs since last ACK */
 551
 552 static void ieee80211_lost_packet(struct sta_info *sta,
 553                                   struct ieee80211_tx_info *info)
 554 {
 555         /* This packet was aggregated but doesn't carry status info */
 556         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 557             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 558                 return;
 559
 560         sta->lost_packets++;
 561         if (!sta->sta.tdls && sta->lost_packets < STA_LOST_PKT_THRESHOLD)
 562                 return;
 563
 564         /*
 565          * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
 566          * of the last packets were lost, and that no ACK was received in the
 567          * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
 568          * mechanism.
 569          */
 570         if (sta->sta.tdls &&
 571             (sta->lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||
 572              time_before(jiffies,
 573                          sta->last_tdls_pkt_time + STA_LOST_TDLS_PKT_TIME)))
 574                 return;
 575
 576         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 577                                     sta->lost_packets, GFP_ATOMIC);
 578         sta->lost_packets = 0;
 579 }
 580
 581 static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
 582                                   struct ieee80211_tx_info *info,
 583                                   int *retry_count)
 584 {
 585         int rates_idx = -1;
 586         int count = -1;
 587         int i;
 588
 589         for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 590                 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 591                     !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
 592                         /* just the first aggr frame carry status info */
 593                         info->status.rates[i].idx = -1;
 594                         info->status.rates[i].count = 0;
 595                         break;
 596                 } else if (info->status.rates[i].idx < 0) {
 597                         break;
 598                 } else if (i >= hw->max_report_rates) {
 599                         /* the HW cannot have attempted that rate */
 600                         info->status.rates[i].idx = -1;
 601                         info->status.rates[i].count = 0;
 602                         break;
 603                 }
 604
 605                 count += info->status.rates[i].count;
 606         }
 607         rates_idx = i - 1;
 608
 609         if (count < 0)
 610                 count = 0;
 611
 612         *retry_count = count;
 613         return rates_idx;
 614 }
 615
 616 void ieee80211_tx_status_noskb(struct ieee80211_hw *hw,
 617                                struct ieee80211_sta *pubsta,
 618                                struct ieee80211_tx_info *info)
 619 {
 620         struct ieee80211_local *local = hw_to_local(hw);
 621         struct ieee80211_supported_band *sband;
 622         int retry_count;
 623         int rates_idx;
 624         bool acked, noack_success;
 625
 626         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 627
 628         sband = hw->wiphy->bands[info->band];
 629
 630         acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 631         noack_success = !!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED);
 632
 633         if (pubsta) {
 634                 struct sta_info *sta;
 635
 636                 sta = container_of(pubsta, struct sta_info, sta);
 637
 638                 if (!acked)
 639                         sta->tx_retry_failed++;
 640                 sta->tx_retry_count += retry_count;
 641
 642                 if (acked) {
 643                         sta->last_rx = jiffies;
 644
 645                         if (sta->lost_packets)
 646                                 sta->lost_packets = 0;
 647
 648                         /* Track when last TDLS packet was ACKed */
 649                         if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 650                                 sta->last_tdls_pkt_time = jiffies;
 651                 } else {
 652                         ieee80211_lost_packet(sta, info);
 653                 }
 654
 655                 rate_control_tx_status_noskb(local, sband, sta, info);
 656         }
 657
 658         if (acked || noack_success) {
 659                 I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 660                 if (!pubsta)
 661                         I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 662                 if (retry_count > 0)
 663                         I802_DEBUG_INC(local->dot11RetryCount);
 664                 if (retry_count > 1)
 665                         I802_DEBUG_INC(local->dot11MultipleRetryCount);
 666         } else {
 667                 I802_DEBUG_INC(local->dot11FailedCount);
 668         }
 669 }
 670 EXPORT_SYMBOL(ieee80211_tx_status_noskb);
 671
 672 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
 673 {
 674         struct sk_buff *skb2;
 675         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 676         struct ieee80211_local *local = hw_to_local(hw);
 677         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 678         __le16 fc;
 679         struct ieee80211_supported_band *sband;
 680         struct ieee80211_sub_if_data *sdata;
 681         struct net_device *prev_dev = NULL;
 682         struct sta_info *sta;
 683         struct rhash_head *tmp;
 684         int retry_count;
 685         int rates_idx;
 686         bool send_to_cooked;
 687         bool acked;
 688         struct ieee80211_bar *bar;
 689         int rtap_len;
 690         int shift = 0;
 691         int tid = IEEE80211_NUM_TIDS;
 692         const struct bucket_table *tbl;
 693
 694         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 695
 696         rcu_read_lock();
 697
 698         sband = local->hw.wiphy->bands[info->band];
 699         fc = hdr->frame_control;
 700
 701         tbl = rht_dereference_rcu(local->sta_hash.tbl, &local->sta_hash);
 702
 703         for_each_sta_info(local, tbl, hdr->addr1, sta, tmp) {
 704                 /* skip wrong virtual interface */
 705                 if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
 706                         continue;
 707
 708                 shift = ieee80211_vif_get_shift(&sta->sdata->vif);
 709
 710                 if (info->flags & IEEE80211_TX_STATUS_EOSP)
 711                         clear_sta_flag(sta, WLAN_STA_SP);
 712
 713                 acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 714                 if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
 715                         /*
 716                          * The STA is in power save mode, so assume
 717                          * that this TX packet failed because of that.
 718                          */
 719                         ieee80211_handle_filtered_frame(local, sta, skb);
 720                         rcu_read_unlock();
 721                         return;
 722                 }
 723
 724                 /* mesh Peer Service Period support */
 725                 if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
 726                     ieee80211_is_data_qos(fc))
 727                         ieee80211_mpsp_trigger_process(
 728                                         ieee80211_get_qos_ctl(hdr),
 729                                         sta, true, acked);
 730
 731                 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL) &&
 732                     (ieee80211_is_data(hdr->frame_control)) &&
 733                     (rates_idx != -1))
 734                         sta->last_tx_rate = info->status.rates[rates_idx];
 735
 736                 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
 737                     (ieee80211_is_data_qos(fc))) {
 738                         u16 ssn;
 739                         u8 *qc;
 740
 741                         qc = ieee80211_get_qos_ctl(hdr);
 742                         tid = qc[0] & 0xf;
 743                         ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
 744                                                 & IEEE80211_SCTL_SEQ);
 745                         ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
 746                                            tid, ssn);
 747                 } else if (ieee80211_is_data_qos(fc)) {
 748                         u8 *qc = ieee80211_get_qos_ctl(hdr);
 749
 750                         tid = qc[0] & 0xf;
 751                 }
 752
 753                 if (!acked && ieee80211_is_back_req(fc)) {
 754                         u16 control;
 755
 756                         /*
 757                          * BAR failed, store the last SSN and retry sending
 758                          * the BAR when the next unicast transmission on the
 759                          * same TID succeeds.
 760                          */
 761                         bar = (struct ieee80211_bar *) skb->data;
 762                         control = le16_to_cpu(bar->control);
 763                         if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
 764                                 u16 ssn = le16_to_cpu(bar->start_seq_num);
 765
 766                                 tid = (control &
 767                                        IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
 768                                       IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
 769
 770                                 ieee80211_set_bar_pending(sta, tid, ssn);
 771                         }
 772                 }
 773
 774                 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
 775                         ieee80211_handle_filtered_frame(local, sta, skb);
 776                         rcu_read_unlock();
 777                         return;
 778                 } else {
 779                         if (!acked)
 780                                 sta->tx_retry_failed++;
 781                         sta->tx_retry_count += retry_count;
 782
 783                         if (ieee80211_is_data_present(fc)) {
 784                                 if (!acked)
 785                                         sta->tx_msdu_failed[tid]++;
 786                                 sta->tx_msdu_retries[tid] += retry_count;
 787                         }
 788                 }
 789
 790                 rate_control_tx_status(local, sband, sta, skb);
 791                 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
 792                         ieee80211s_update_metric(local, sta, skb);
 793
 794                 if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
 795                         ieee80211_frame_acked(sta, skb);
 796
 797                 if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
 798                     ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 799                         ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
 800                                                 acked, info->status.tx_time);
 801
 802                 if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
 803                         if (info->flags & IEEE80211_TX_STAT_ACK) {
 804                                 if (sta->lost_packets)
 805                                         sta->lost_packets = 0;
 806
 807                                 /* Track when last TDLS packet was ACKed */
 808                                 if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 809                                         sta->last_tdls_pkt_time = jiffies;
 810                         } else {
 811                                 ieee80211_lost_packet(sta, info);
 812                         }
 813                 }
 814
 815                 if (acked)
 816                         sta->last_ack_signal = info->status.ack_signal;
 817         }
 818
 819         rcu_read_unlock();
 820
 821         ieee80211_led_tx(local);
 822
 823         /* SNMP counters
 824          * Fragments are passed to low-level drivers as separate skbs, so these
 825          * are actually fragments, not frames. Update frame counters only for
 826          * the first fragment of the frame. */
 827         if ((info->flags & IEEE80211_TX_STAT_ACK) ||
 828             (info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED)) {
 829                 if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
 830                         I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 831                         if (is_multicast_ether_addr(ieee80211_get_DA(hdr)))
 832                                 I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 833                         if (retry_count > 0)
 834                                 I802_DEBUG_INC(local->dot11RetryCount);
 835                         if (retry_count > 1)
 836                                 I802_DEBUG_INC(local->dot11MultipleRetryCount);
 837                 }
 838
 839                 /* This counter shall be incremented for an acknowledged MPDU
 840                  * with an individual address in the address 1 field or an MPDU
 841                  * with a multicast address in the address 1 field of type Data
 842                  * or Management. */
 843                 if (!is_multicast_ether_addr(hdr->addr1) ||
 844                     ieee80211_is_data(fc) ||
 845                     ieee80211_is_mgmt(fc))
 846                         I802_DEBUG_INC(local->dot11TransmittedFragmentCount);
 847         } else {
 848                 if (ieee80211_is_first_frag(hdr->seq_ctrl))
 849                         I802_DEBUG_INC(local->dot11FailedCount);
 850         }
 851
 852         if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
 853             ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS) &&
 854             !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
 855             local->ps_sdata && !(local->scanning)) {
 856                 if (info->flags & IEEE80211_TX_STAT_ACK) {
 857                         local->ps_sdata->u.mgd.flags |=
 858                                         IEEE80211_STA_NULLFUNC_ACKED;
 859                 } else
 860                         mod_timer(&local->dynamic_ps_timer, jiffies +
 861                                         msecs_to_jiffies(10));
 862         }
 863
 864         ieee80211_report_used_skb(local, skb, false);
 865
 866         /* this was a transmitted frame, but now we want to reuse it */
 867         skb_orphan(skb);
 868
 869         /* Need to make a copy before skb->cb gets cleared */
 870         send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
 871                          !(ieee80211_is_data(fc));
 872
 873         /*
 874          * This is a bit racy but we can avoid a lot of work
 875          * with this test...
 876          */
 877         if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
 878                 dev_kfree_skb(skb);
 879                 return;
 880         }
 881
 882         /* send frame to monitor interfaces now */
 883         rtap_len = ieee80211_tx_radiotap_len(info);
 884         if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
 885                 pr_err("ieee80211_tx_status: headroom too small\n");
 886                 dev_kfree_skb(skb);
 887                 return;
 888         }
 889         ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
 890                                          rtap_len, shift);
 891
 892         /* XXX: is this sufficient for BPF? */
 893         skb_set_mac_header(skb, 0);
 894         skb->ip_summed = CHECKSUM_UNNECESSARY;
 895         skb->pkt_type = PACKET_OTHERHOST;
 896         skb->protocol = htons(ETH_P_802_2);
 897         memset(skb->cb, 0, sizeof(skb->cb));
 898
 899         rcu_read_lock();
 900         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 901                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
 902                         if (!ieee80211_sdata_running(sdata))
 903                                 continue;
 904
 905                         if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
 906                             !send_to_cooked)
 907                                 continue;
 908
 909                         if (prev_dev) {
 910                                 skb2 = skb_clone(skb, GFP_ATOMIC);
 911                                 if (skb2) {
 912                                         skb2->dev = prev_dev;
 913                                         netif_rx(skb2);
 914                                 }
 915                         }
 916
 917                         prev_dev = sdata->dev;
 918                 }
 919         }
 920         if (prev_dev) {
 921                 skb->dev = prev_dev;
 922                 netif_rx(skb);
 923                 skb = NULL;
 924         }
 925         rcu_read_unlock();
 926         dev_kfree_skb(skb);
 927 }
 928 EXPORT_SYMBOL(ieee80211_tx_status);
 929
 930 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
 931 {
 932         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 933         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 934                                     num_packets, GFP_ATOMIC);
 935 }
 936 EXPORT_SYMBOL(ieee80211_report_low_ack);
 937
 938 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
 939 {
 940         struct ieee80211_local *local = hw_to_local(hw);
 941
 942         ieee80211_report_used_skb(local, skb, true);
 943         dev_kfree_skb_any(skb);
 944 }
 945 EXPORT_SYMBOL(ieee80211_free_txskb);
 946
 947 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
 948                               struct sk_buff_head *skbs)
 949 {
 950         struct sk_buff *skb;
 951
 952         while ((skb = __skb_dequeue(skbs)))
 953                 ieee80211_free_txskb(hw, skb);
 954 }