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->status_stats.filtered++;
  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->rx_stats.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             !ieee80211_has_protected(mgmt->frame_control) &&
 198             mgmt->u.action.category == WLAN_CATEGORY_HT &&
 199             mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
 200             ieee80211_sdata_running(sdata)) {
 201                 enum ieee80211_smps_mode smps_mode;
 202
 203                 switch (mgmt->u.action.u.ht_smps.smps_control) {
 204                 case WLAN_HT_SMPS_CONTROL_DYNAMIC:
 205                         smps_mode = IEEE80211_SMPS_DYNAMIC;
 206                         break;
 207                 case WLAN_HT_SMPS_CONTROL_STATIC:
 208                         smps_mode = IEEE80211_SMPS_STATIC;
 209                         break;
 210                 case WLAN_HT_SMPS_CONTROL_DISABLED:
 211                 default: /* shouldn't happen since we don't send that */
 212                         smps_mode = IEEE80211_SMPS_OFF;
 213                         break;
 214                 }
 215
 216                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 217                         /*
 218                          * This update looks racy, but isn't -- if we come
 219                          * here we've definitely got a station that we're
 220                          * talking to, and on a managed interface that can
 221                          * only be the AP. And the only other place updating
 222                          * this variable in managed mode is before association.
 223                          */
 224                         sdata->smps_mode = smps_mode;
 225                         ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
 226                 } else if (sdata->vif.type == NL80211_IFTYPE_AP ||
 227                            sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 228                         sta->known_smps_mode = smps_mode;
 229                 }
 230         }
 231 }
 232
 233 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
 234 {
 235         struct tid_ampdu_tx *tid_tx;
 236
 237         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 238         if (!tid_tx)
 239                 return;
 240
 241         tid_tx->failed_bar_ssn = ssn;
 242         tid_tx->bar_pending = true;
 243 }
 244
 245 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
 246 {
 247         int len = sizeof(struct ieee80211_radiotap_header);
 248
 249         /* IEEE80211_RADIOTAP_RATE rate */
 250         if (info->status.rates[0].idx >= 0 &&
 251             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 252                                              IEEE80211_TX_RC_VHT_MCS)))
 253                 len += 2;
 254
 255         /* IEEE80211_RADIOTAP_TX_FLAGS */
 256         len += 2;
 257
 258         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 259         len += 1;
 260
 261         /* IEEE80211_RADIOTAP_MCS
 262          * IEEE80211_RADIOTAP_VHT */
 263         if (info->status.rates[0].idx >= 0) {
 264                 if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
 265                         len += 3;
 266                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
 267                         len = ALIGN(len, 2) + 12;
 268         }
 269
 270         return len;
 271 }
 272
 273 static void
 274 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
 275                                  struct ieee80211_supported_band *sband,
 276                                  struct sk_buff *skb, int retry_count,
 277                                  int rtap_len, int shift)
 278 {
 279         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 280         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 281         struct ieee80211_radiotap_header *rthdr;
 282         unsigned char *pos;
 283         u16 txflags;
 284
 285         rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len);
 286
 287         memset(rthdr, 0, rtap_len);
 288         rthdr->it_len = cpu_to_le16(rtap_len);
 289         rthdr->it_present =
 290                 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
 291                             (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
 292         pos = (unsigned char *)(rthdr + 1);
 293
 294         /*
 295          * XXX: Once radiotap gets the bitmap reset thing the vendor
 296          *      extensions proposal contains, we can actually report
 297          *      the whole set of tries we did.
 298          */
 299
 300         /* IEEE80211_RADIOTAP_RATE */
 301         if (info->status.rates[0].idx >= 0 &&
 302             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 303                                              IEEE80211_TX_RC_VHT_MCS))) {
 304                 u16 rate;
 305
 306                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 307                 rate = sband->bitrates[info->status.rates[0].idx].bitrate;
 308                 *pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
 309                 /* padding for tx flags */
 310                 pos += 2;
 311         }
 312
 313         /* IEEE80211_RADIOTAP_TX_FLAGS */
 314         txflags = 0;
 315         if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
 316             !is_multicast_ether_addr(hdr->addr1))
 317                 txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
 318
 319         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
 320                 txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
 321         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
 322                 txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
 323
 324         put_unaligned_le16(txflags, pos);
 325         pos += 2;
 326
 327         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 328         /* for now report the total retry_count */
 329         *pos = retry_count;
 330         pos++;
 331
 332         if (info->status.rates[0].idx < 0)
 333                 return;
 334
 335         /* IEEE80211_RADIOTAP_MCS
 336          * IEEE80211_RADIOTAP_VHT */
 337         if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
 338                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 339                 pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
 340                          IEEE80211_RADIOTAP_MCS_HAVE_GI |
 341                          IEEE80211_RADIOTAP_MCS_HAVE_BW;
 342                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 343                         pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
 344                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 345                         pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
 346                 if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
 347                         pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 348                 pos[2] = info->status.rates[0].idx;
 349                 pos += 3;
 350         } else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
 351                 u16 known = local->hw.radiotap_vht_details &
 352                         (IEEE80211_RADIOTAP_VHT_KNOWN_GI |
 353                          IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
 354
 355                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 356
 357                 /* required alignment from rthdr */
 358                 pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
 359
 360                 /* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
 361                 put_unaligned_le16(known, pos);
 362                 pos += 2;
 363
 364                 /* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
 365                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 366                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 367                 pos++;
 368
 369                 /* u8 bandwidth */
 370                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 371                         *pos = 1;
 372                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
 373                         *pos = 4;
 374                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
 375                         *pos = 11;
 376                 else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
 377                         *pos = 0;
 378                 pos++;
 379
 380                 /* u8 mcs_nss[4] */
 381                 *pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
 382                         ieee80211_rate_get_vht_nss(&info->status.rates[0]);
 383                 pos += 4;
 384
 385                 /* u8 coding */
 386                 pos++;
 387                 /* u8 group_id */
 388                 pos++;
 389                 /* u16 partial_aid */
 390                 pos += 2;
 391         }
 392 }
 393
 394 /*
 395  * Handles the tx for TDLS teardown frames.
 396  * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
 397  */
 398 static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
 399                                         struct ieee80211_sub_if_data *sdata,
 400                                         struct sk_buff *skb, u32 flags)
 401 {
 402         struct sk_buff *teardown_skb;
 403         struct sk_buff *orig_teardown_skb;
 404         bool is_teardown = false;
 405
 406         /* Get the teardown data we need and free the lock */
 407         spin_lock(&sdata->u.mgd.teardown_lock);
 408         teardown_skb = sdata->u.mgd.teardown_skb;
 409         orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
 410         if ((skb == orig_teardown_skb) && teardown_skb) {
 411                 sdata->u.mgd.teardown_skb = NULL;
 412                 sdata->u.mgd.orig_teardown_skb = NULL;
 413                 is_teardown = true;
 414         }
 415         spin_unlock(&sdata->u.mgd.teardown_lock);
 416
 417         if (is_teardown) {
 418                 /* This mechanism relies on being able to get ACKs */
 419                 WARN_ON(!ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS));
 420
 421                 /* Check if peer has ACKed */
 422                 if (flags & IEEE80211_TX_STAT_ACK) {
 423                         dev_kfree_skb_any(teardown_skb);
 424                 } else {
 425                         tdls_dbg(sdata,
 426                                  "TDLS Resending teardown through AP\n");
 427
 428                         ieee80211_subif_start_xmit(teardown_skb, skb->dev);
 429                 }
 430         }
 431 }
 432
 433 static struct ieee80211_sub_if_data *
 434 ieee80211_sdata_from_skb(struct ieee80211_local *local, struct sk_buff *skb)
 435 {
 436         struct ieee80211_sub_if_data *sdata;
 437
 438         if (skb->dev) {
 439                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 440                         if (!sdata->dev)
 441                                 continue;
 442
 443                         if (skb->dev == sdata->dev)
 444                                 return sdata;
 445                 }
 446
 447                 return NULL;
 448         }
 449
 450         return rcu_dereference(local->p2p_sdata);
 451 }
 452
 453 static void ieee80211_report_ack_skb(struct ieee80211_local *local,
 454                                      struct ieee80211_tx_info *info,
 455                                      bool acked, bool dropped)
 456 {
 457         struct sk_buff *skb;
 458         unsigned long flags;
 459
 460         spin_lock_irqsave(&local->ack_status_lock, flags);
 461         skb = idr_find(&local->ack_status_frames, info->ack_frame_id);
 462         if (skb)
 463                 idr_remove(&local->ack_status_frames, info->ack_frame_id);
 464         spin_unlock_irqrestore(&local->ack_status_lock, flags);
 465
 466         if (!skb)
 467                 return;
 468
 469         if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {
 470                 u64 cookie = IEEE80211_SKB_CB(skb)->ack.cookie;
 471                 struct ieee80211_sub_if_data *sdata;
 472                 struct ieee80211_hdr *hdr = (void *)skb->data;
 473
 474                 rcu_read_lock();
 475                 sdata = ieee80211_sdata_from_skb(local, skb);
 476                 if (sdata) {
 477                         if (ieee80211_is_any_nullfunc(hdr->frame_control))
 478                                 cfg80211_probe_status(sdata->dev, hdr->addr1,
 479                                                       cookie, acked,
 480                                                       GFP_ATOMIC);
 481                         else
 482                                 cfg80211_mgmt_tx_status(&sdata->wdev, cookie,
 483                                                         skb->data, skb->len,
 484                                                         acked, GFP_ATOMIC);
 485                 }
 486                 rcu_read_unlock();
 487
 488                 dev_kfree_skb_any(skb);
 489         } else if (dropped) {
 490                 dev_kfree_skb_any(skb);
 491         } else {
 492                 /* consumes skb */
 493                 skb_complete_wifi_ack(skb, acked);
 494         }
 495 }
 496
 497 static void ieee80211_report_used_skb(struct ieee80211_local *local,
 498                                       struct sk_buff *skb, bool dropped)
 499 {
 500         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 501         struct ieee80211_hdr *hdr = (void *)skb->data;
 502         bool acked = info->flags & IEEE80211_TX_STAT_ACK;
 503
 504         if (dropped)
 505                 acked = false;
 506
 507         if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
 508                 struct ieee80211_sub_if_data *sdata;
 509
 510                 rcu_read_lock();
 511
 512                 sdata = ieee80211_sdata_from_skb(local, skb);
 513
 514                 if (!sdata) {
 515                         skb->dev = NULL;
 516                 } else {
 517                         unsigned int hdr_size =
 518                                 ieee80211_hdrlen(hdr->frame_control);
 519
 520                         /* Check to see if packet is a TDLS teardown packet */
 521                         if (ieee80211_is_data(hdr->frame_control) &&
 522                             (ieee80211_get_tdls_action(skb, hdr_size) ==
 523                              WLAN_TDLS_TEARDOWN))
 524                                 ieee80211_tdls_td_tx_handle(local, sdata, skb,
 525                                                             info->flags);
 526                         else
 527                                 ieee80211_mgd_conn_tx_status(sdata,
 528                                                              hdr->frame_control,
 529                                                              acked);
 530                 }
 531
 532                 rcu_read_unlock();
 533         } else if (info->ack_frame_id) {
 534                 ieee80211_report_ack_skb(local, info, acked, dropped);
 535         }
 536 }
 537
 538 /*
 539  * Use a static threshold for now, best value to be determined
 540  * by testing ...
 541  * Should it depend on:
 542  *  - on # of retransmissions
 543  *  - current throughput (higher value for higher tpt)?
 544  */
 545 #define STA_LOST_PKT_THRESHOLD  50
 546 #define STA_LOST_TDLS_PKT_THRESHOLD     10
 547 #define STA_LOST_TDLS_PKT_TIME          (10*HZ) /* 10secs since last ACK */
 548
 549 static void ieee80211_lost_packet(struct sta_info *sta,
 550                                   struct ieee80211_tx_info *info)
 551 {
 552         /* This packet was aggregated but doesn't carry status info */
 553         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 554             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 555                 return;
 556
 557         sta->status_stats.lost_packets++;
 558         if (!sta->sta.tdls &&
 559             sta->status_stats.lost_packets < STA_LOST_PKT_THRESHOLD)
 560                 return;
 561
 562         /*
 563          * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
 564          * of the last packets were lost, and that no ACK was received in the
 565          * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
 566          * mechanism.
 567          */
 568         if (sta->sta.tdls &&
 569             (sta->status_stats.lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||
 570              time_before(jiffies,
 571                          sta->status_stats.last_tdls_pkt_time +
 572                          STA_LOST_TDLS_PKT_TIME)))
 573                 return;
 574
 575         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 576                                     sta->status_stats.lost_packets, GFP_ATOMIC);
 577         sta->status_stats.lost_packets = 0;
 578 }
 579
 580 static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
 581                                   struct ieee80211_tx_info *info,
 582                                   int *retry_count)
 583 {
 584         int rates_idx = -1;
 585         int count = -1;
 586         int i;
 587
 588         for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 589                 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 590                     !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
 591                         /* just the first aggr frame carry status info */
 592                         info->status.rates[i].idx = -1;
 593                         info->status.rates[i].count = 0;
 594                         break;
 595                 } else if (info->status.rates[i].idx < 0) {
 596                         break;
 597                 } else if (i >= hw->max_report_rates) {
 598                         /* the HW cannot have attempted that rate */
 599                         info->status.rates[i].idx = -1;
 600                         info->status.rates[i].count = 0;
 601                         break;
 602                 }
 603
 604                 count += info->status.rates[i].count;
 605         }
 606         rates_idx = i - 1;
 607
 608         if (count < 0)
 609                 count = 0;
 610
 611         *retry_count = count;
 612         return rates_idx;
 613 }
 614
 615 void ieee80211_tx_status_noskb(struct ieee80211_hw *hw,
 616                                struct ieee80211_sta *pubsta,
 617                                struct ieee80211_tx_info *info)
 618 {
 619         struct ieee80211_local *local = hw_to_local(hw);
 620         struct ieee80211_supported_band *sband;
 621         int retry_count;
 622         int rates_idx;
 623         bool acked, noack_success;
 624
 625         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 626
 627         sband = hw->wiphy->bands[info->band];
 628
 629         acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 630         noack_success = !!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED);
 631
 632         if (pubsta) {
 633                 struct sta_info *sta;
 634
 635                 sta = container_of(pubsta, struct sta_info, sta);
 636
 637                 if (!acked)
 638                         sta->status_stats.retry_failed++;
 639                 sta->status_stats.retry_count += retry_count;
 640
 641                 if (acked) {
 642                         sta->rx_stats.last_rx = jiffies;
 643
 644                         if (sta->status_stats.lost_packets)
 645                                 sta->status_stats.lost_packets = 0;
 646
 647                         /* Track when last TDLS packet was ACKed */
 648                         if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 649                                 sta->status_stats.last_tdls_pkt_time = jiffies;
 650                 } else if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
 651                         return;
 652                 } else {
 653                         ieee80211_lost_packet(sta, info);
 654                 }
 655
 656                 rate_control_tx_status_noskb(local, sband, sta, info);
 657         }
 658
 659         if (acked || noack_success) {
 660                 I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 661                 if (!pubsta)
 662                         I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 663                 if (retry_count > 0)
 664                         I802_DEBUG_INC(local->dot11RetryCount);
 665                 if (retry_count > 1)
 666                         I802_DEBUG_INC(local->dot11MultipleRetryCount);
 667         } else {
 668                 I802_DEBUG_INC(local->dot11FailedCount);
 669         }
 670 }
 671 EXPORT_SYMBOL(ieee80211_tx_status_noskb);
 672
 673 void ieee80211_tx_monitor(struct ieee80211_local *local, struct sk_buff *skb,
 674                           struct ieee80211_supported_band *sband,
 675                           int retry_count, int shift, bool send_to_cooked)
 676 {
 677         struct sk_buff *skb2;
 678         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 679         struct ieee80211_sub_if_data *sdata;
 680         struct net_device *prev_dev = NULL;
 681         int rtap_len;
 682
 683         /* send frame to monitor interfaces now */
 684         rtap_len = ieee80211_tx_radiotap_len(info);
 685         if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
 686                 pr_err("ieee80211_tx_status: headroom too small\n");
 687                 dev_kfree_skb(skb);
 688                 return;
 689         }
 690         ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
 691                                          rtap_len, shift);
 692
 693         /* XXX: is this sufficient for BPF? */
 694         skb_set_mac_header(skb, 0);
 695         skb->ip_summed = CHECKSUM_UNNECESSARY;
 696         skb->pkt_type = PACKET_OTHERHOST;
 697         skb->protocol = htons(ETH_P_802_2);
 698         memset(skb->cb, 0, sizeof(skb->cb));
 699
 700         rcu_read_lock();
 701         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 702                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
 703                         if (!ieee80211_sdata_running(sdata))
 704                                 continue;
 705
 706                         if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
 707                             !send_to_cooked)
 708                                 continue;
 709
 710                         if (prev_dev) {
 711                                 skb2 = skb_clone(skb, GFP_ATOMIC);
 712                                 if (skb2) {
 713                                         skb2->dev = prev_dev;
 714                                         netif_rx(skb2);
 715                                 }
 716                         }
 717
 718                         prev_dev = sdata->dev;
 719                 }
 720         }
 721         if (prev_dev) {
 722                 skb->dev = prev_dev;
 723                 netif_rx(skb);
 724                 skb = NULL;
 725         }
 726         rcu_read_unlock();
 727         dev_kfree_skb(skb);
 728 }
 729
 730 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
 731 {
 732         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 733         struct ieee80211_local *local = hw_to_local(hw);
 734         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 735         __le16 fc;
 736         struct ieee80211_supported_band *sband;
 737         struct sta_info *sta;
 738         struct rhash_head *tmp;
 739         int retry_count;
 740         int rates_idx;
 741         bool send_to_cooked;
 742         bool acked;
 743         struct ieee80211_bar *bar;
 744         int shift = 0;
 745         int tid = IEEE80211_NUM_TIDS;
 746         const struct bucket_table *tbl;
 747
 748         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 749
 750         rcu_read_lock();
 751
 752         sband = local->hw.wiphy->bands[info->band];
 753         fc = hdr->frame_control;
 754
 755         tbl = rht_dereference_rcu(local->sta_hash.tbl, &local->sta_hash);
 756
 757         for_each_sta_info(local, tbl, hdr->addr1, sta, tmp) {
 758                 /* skip wrong virtual interface */
 759                 if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
 760                         continue;
 761
 762                 shift = ieee80211_vif_get_shift(&sta->sdata->vif);
 763
 764                 if (info->flags & IEEE80211_TX_STATUS_EOSP)
 765                         clear_sta_flag(sta, WLAN_STA_SP);
 766
 767                 acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 768                 if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
 769                         /*
 770                          * The STA is in power save mode, so assume
 771                          * that this TX packet failed because of that.
 772                          */
 773                         ieee80211_handle_filtered_frame(local, sta, skb);
 774                         rcu_read_unlock();
 775                         return;
 776                 }
 777
 778                 /* mesh Peer Service Period support */
 779                 if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
 780                     ieee80211_is_data_qos(fc))
 781                         ieee80211_mpsp_trigger_process(
 782                                         ieee80211_get_qos_ctl(hdr),
 783                                         sta, true, acked);
 784
 785                 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL) &&
 786                     (ieee80211_is_data(hdr->frame_control)) &&
 787                     (rates_idx != -1))
 788                         sta->tx_stats.last_rate =
 789                                 info->status.rates[rates_idx];
 790
 791                 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
 792                     (ieee80211_is_data_qos(fc))) {
 793                         u16 ssn;
 794                         u8 *qc;
 795
 796                         qc = ieee80211_get_qos_ctl(hdr);
 797                         tid = qc[0] & 0xf;
 798                         ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
 799                                                 & IEEE80211_SCTL_SEQ);
 800                         ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
 801                                            tid, ssn);
 802                 } else if (ieee80211_is_data_qos(fc)) {
 803                         u8 *qc = ieee80211_get_qos_ctl(hdr);
 804
 805                         tid = qc[0] & 0xf;
 806                 }
 807
 808                 if (!acked && ieee80211_is_back_req(fc)) {
 809                         u16 control;
 810
 811                         /*
 812                          * BAR failed, store the last SSN and retry sending
 813                          * the BAR when the next unicast transmission on the
 814                          * same TID succeeds.
 815                          */
 816                         bar = (struct ieee80211_bar *) skb->data;
 817                         control = le16_to_cpu(bar->control);
 818                         if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
 819                                 u16 ssn = le16_to_cpu(bar->start_seq_num);
 820
 821                                 tid = (control &
 822                                        IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
 823                                       IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
 824
 825                                 ieee80211_set_bar_pending(sta, tid, ssn);
 826                         }
 827                 }
 828
 829                 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
 830                         ieee80211_handle_filtered_frame(local, sta, skb);
 831                         rcu_read_unlock();
 832                         return;
 833                 } else {
 834                         if (!acked)
 835                                 sta->status_stats.retry_failed++;
 836                         sta->status_stats.retry_count += retry_count;
 837
 838                         if (ieee80211_is_data_present(fc)) {
 839                                 if (!acked)
 840                                         sta->status_stats.msdu_failed[tid]++;
 841
 842                                 sta->status_stats.msdu_retries[tid] +=
 843                                         retry_count;
 844                         }
 845                 }
 846
 847                 rate_control_tx_status(local, sband, sta, skb);
 848                 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
 849                         ieee80211s_update_metric(local, sta, skb);
 850
 851                 if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
 852                         ieee80211_frame_acked(sta, skb);
 853
 854                 if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
 855                     ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
 856                         ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
 857                                                 acked, info->status.tx_time);
 858
 859                 if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
 860                         if (info->flags & IEEE80211_TX_STAT_ACK) {
 861                                 if (sta->status_stats.lost_packets)
 862                                         sta->status_stats.lost_packets = 0;
 863
 864                                 /* Track when last TDLS packet was ACKed */
 865                                 if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 866                                         sta->status_stats.last_tdls_pkt_time =
 867                                                 jiffies;
 868                         } else {
 869                                 ieee80211_lost_packet(sta, info);
 870                         }
 871                 }
 872         }
 873
 874         rcu_read_unlock();
 875
 876         ieee80211_led_tx(local);
 877
 878         /* SNMP counters
 879          * Fragments are passed to low-level drivers as separate skbs, so these
 880          * are actually fragments, not frames. Update frame counters only for
 881          * the first fragment of the frame. */
 882         if ((info->flags & IEEE80211_TX_STAT_ACK) ||
 883             (info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED)) {
 884                 if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
 885                         I802_DEBUG_INC(local->dot11TransmittedFrameCount);
 886                         if (is_multicast_ether_addr(ieee80211_get_DA(hdr)))
 887                                 I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
 888                         if (retry_count > 0)
 889                                 I802_DEBUG_INC(local->dot11RetryCount);
 890                         if (retry_count > 1)
 891                                 I802_DEBUG_INC(local->dot11MultipleRetryCount);
 892                 }
 893
 894                 /* This counter shall be incremented for an acknowledged MPDU
 895                  * with an individual address in the address 1 field or an MPDU
 896                  * with a multicast address in the address 1 field of type Data
 897                  * or Management. */
 898                 if (!is_multicast_ether_addr(hdr->addr1) ||
 899                     ieee80211_is_data(fc) ||
 900                     ieee80211_is_mgmt(fc))
 901                         I802_DEBUG_INC(local->dot11TransmittedFragmentCount);
 902         } else {
 903                 if (ieee80211_is_first_frag(hdr->seq_ctrl))
 904                         I802_DEBUG_INC(local->dot11FailedCount);
 905         }
 906
 907         if (ieee80211_is_any_nullfunc(fc) && ieee80211_has_pm(fc) &&
 908             ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS) &&
 909             !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
 910             local->ps_sdata && !(local->scanning)) {
 911                 if (info->flags & IEEE80211_TX_STAT_ACK) {
 912                         local->ps_sdata->u.mgd.flags |=
 913                                         IEEE80211_STA_NULLFUNC_ACKED;
 914                 } else
 915                         mod_timer(&local->dynamic_ps_timer, jiffies +
 916                                         msecs_to_jiffies(10));
 917         }
 918
 919         ieee80211_report_used_skb(local, skb, false);
 920
 921         /* this was a transmitted frame, but now we want to reuse it */
 922         skb_orphan(skb);
 923
 924         /* Need to make a copy before skb->cb gets cleared */
 925         send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
 926                          !(ieee80211_is_data(fc));
 927
 928         /*
 929          * This is a bit racy but we can avoid a lot of work
 930          * with this test...
 931          */
 932         if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
 933                 dev_kfree_skb(skb);
 934                 return;
 935         }
 936
 937         /* send to monitor interfaces */
 938         ieee80211_tx_monitor(local, skb, sband, retry_count, shift, send_to_cooked);
 939 }
 940 EXPORT_SYMBOL(ieee80211_tx_status);
 941
 942 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
 943 {
 944         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 945         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 946                                     num_packets, GFP_ATOMIC);
 947 }
 948 EXPORT_SYMBOL(ieee80211_report_low_ack);
 949
 950 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
 951 {
 952         struct ieee80211_local *local = hw_to_local(hw);
 953
 954         ieee80211_report_used_skb(local, skb, true);
 955         dev_kfree_skb_any(skb);
 956 }
 957 EXPORT_SYMBOL(ieee80211_free_txskb);
 958
 959 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
 960                               struct sk_buff_head *skbs)
 961 {
 962         struct sk_buff *skb;
 963
 964         while ((skb = __skb_dequeue(skbs)))
 965                 ieee80211_free_txskb(hw, skb);
 966 }