net/mac80211/ht.c

   1 /*
   2  * HT handling
   3  *
   4  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
   5  * Copyright 2002-2005, Instant802 Networks, Inc.
   6  * Copyright 2005-2006, Devicescape Software, Inc.
   7  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   9  * Copyright 2007-2010, Intel Corporation
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/ieee80211.h>
  17 #include <net/mac80211.h>
  18 #include "ieee80211_i.h"
  19 #include "rate.h"
  20
  21 bool ieee80111_cfg_override_disables_ht40(struct ieee80211_sub_if_data *sdata)
  22 {
  23         const __le16 flg = cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40);
  24         if ((sdata->u.mgd.ht_capa_mask.cap_info & flg) &&
  25             !(sdata->u.mgd.ht_capa.cap_info & flg))
  26                 return true;
  27         return false;
  28 }
  29
  30 void __check_htcap_disable(struct ieee80211_sub_if_data *sdata,
  31                            struct ieee80211_sta_ht_cap *ht_cap,
  32                            u16 flag)
  33 {
  34         __le16 le_flag = cpu_to_le16(flag);
  35         if (sdata->u.mgd.ht_capa_mask.cap_info & le_flag) {
  36                 if (!(sdata->u.mgd.ht_capa.cap_info & le_flag))
  37                         ht_cap->cap &= ~flag;
  38         }
  39 }
  40
  41 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
  42                                      struct ieee80211_sta_ht_cap *ht_cap)
  43 {
  44         u8 *scaps = (u8 *)(&sdata->u.mgd.ht_capa.mcs.rx_mask);
  45         u8 *smask = (u8 *)(&sdata->u.mgd.ht_capa_mask.mcs.rx_mask);
  46         int i;
  47
  48         if (sdata->vif.type != NL80211_IFTYPE_STATION) {
  49                 WARN_ON_ONCE(sdata->vif.type != NL80211_IFTYPE_STATION);
  50                 return;
  51         }
  52
  53         /* NOTE:  If you add more over-rides here, update register_hw
  54          * ht_capa_mod_msk logic in main.c as well.
  55          * And, if this method can ever change ht_cap.ht_supported, fix
  56          * the check in ieee80211_add_ht_ie.
  57          */
  58
  59         /* check for HT over-rides, MCS rates first. */
  60         for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
  61                 u8 m = smask[i];
  62                 ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
  63                 /* Add back rates that are supported */
  64                 ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
  65         }
  66
  67         /* Force removal of HT-40 capabilities? */
  68         __check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_SUP_WIDTH_20_40);
  69         __check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_SGI_40);
  70
  71         /* Allow user to disable the max-AMSDU bit. */
  72         __check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_MAX_AMSDU);
  73
  74         /* Allow user to decrease AMPDU factor */
  75         if (sdata->u.mgd.ht_capa_mask.ampdu_params_info &
  76             IEEE80211_HT_AMPDU_PARM_FACTOR) {
  77                 u8 n = sdata->u.mgd.ht_capa.ampdu_params_info
  78                         & IEEE80211_HT_AMPDU_PARM_FACTOR;
  79                 if (n < ht_cap->ampdu_factor)
  80                         ht_cap->ampdu_factor = n;
  81         }
  82
  83         /* Allow the user to increase AMPDU density. */
  84         if (sdata->u.mgd.ht_capa_mask.ampdu_params_info &
  85             IEEE80211_HT_AMPDU_PARM_DENSITY) {
  86                 u8 n = (sdata->u.mgd.ht_capa.ampdu_params_info &
  87                         IEEE80211_HT_AMPDU_PARM_DENSITY)
  88                         >> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
  89                 if (n > ht_cap->ampdu_density)
  90                         ht_cap->ampdu_density = n;
  91         }
  92 }
  93
  94
  95 void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
  96                                        struct ieee80211_supported_band *sband,
  97                                        struct ieee80211_ht_cap *ht_cap_ie,
  98                                        struct ieee80211_sta_ht_cap *ht_cap)
  99 {
 100         u8 ampdu_info, tx_mcs_set_cap;
 101         int i, max_tx_streams;
 102
 103         BUG_ON(!ht_cap);
 104
 105         memset(ht_cap, 0, sizeof(*ht_cap));
 106
 107         if (!ht_cap_ie || !sband->ht_cap.ht_supported)
 108                 return;
 109
 110         ht_cap->ht_supported = true;
 111
 112         /*
 113          * The bits listed in this expression should be
 114          * the same for the peer and us, if the station
 115          * advertises more then we can't use those thus
 116          * we mask them out.
 117          */
 118         ht_cap->cap = le16_to_cpu(ht_cap_ie->cap_info) &
 119                 (sband->ht_cap.cap |
 120                  ~(IEEE80211_HT_CAP_LDPC_CODING |
 121                    IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
 122                    IEEE80211_HT_CAP_GRN_FLD |
 123                    IEEE80211_HT_CAP_SGI_20 |
 124                    IEEE80211_HT_CAP_SGI_40 |
 125                    IEEE80211_HT_CAP_DSSSCCK40));
 126         /*
 127          * The STBC bits are asymmetric -- if we don't have
 128          * TX then mask out the peer's RX and vice versa.
 129          */
 130         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_TX_STBC))
 131                 ht_cap->cap &= ~IEEE80211_HT_CAP_RX_STBC;
 132         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_RX_STBC))
 133                 ht_cap->cap &= ~IEEE80211_HT_CAP_TX_STBC;
 134
 135         ampdu_info = ht_cap_ie->ampdu_params_info;
 136         ht_cap->ampdu_factor =
 137                 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
 138         ht_cap->ampdu_density =
 139                 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
 140
 141         /* own MCS TX capabilities */
 142         tx_mcs_set_cap = sband->ht_cap.mcs.tx_params;
 143
 144         /* Copy peer MCS TX capabilities, the driver might need them. */
 145         ht_cap->mcs.tx_params = ht_cap_ie->mcs.tx_params;
 146
 147         /* can we TX with MCS rates? */
 148         if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
 149                 return;
 150
 151         /* Counting from 0, therefore +1 */
 152         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
 153                 max_tx_streams =
 154                         ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
 155                                 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
 156         else
 157                 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
 158
 159         /*
 160          * 802.11n-2009 20.3.5 / 20.6 says:
 161          * - indices 0 to 7 and 32 are single spatial stream
 162          * - 8 to 31 are multiple spatial streams using equal modulation
 163          *   [8..15 for two streams, 16..23 for three and 24..31 for four]
 164          * - remainder are multiple spatial streams using unequal modulation
 165          */
 166         for (i = 0; i < max_tx_streams; i++)
 167                 ht_cap->mcs.rx_mask[i] =
 168                         sband->ht_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
 169
 170         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
 171                 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
 172                      i < IEEE80211_HT_MCS_MASK_LEN; i++)
 173                         ht_cap->mcs.rx_mask[i] =
 174                                 sband->ht_cap.mcs.rx_mask[i] &
 175                                         ht_cap_ie->mcs.rx_mask[i];
 176
 177         /* handle MCS rate 32 too */
 178         if (sband->ht_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
 179                 ht_cap->mcs.rx_mask[32/8] |= 1;
 180
 181         /*
 182          * If user has specified capability over-rides, take care
 183          * of that here.
 184          */
 185         ieee80211_apply_htcap_overrides(sdata, ht_cap);
 186 }
 187
 188 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx)
 189 {
 190         int i;
 191
 192         cancel_work_sync(&sta->ampdu_mlme.work);
 193
 194         for (i = 0; i <  STA_TID_NUM; i++) {
 195                 __ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR, tx);
 196                 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
 197                                                WLAN_REASON_QSTA_LEAVE_QBSS, tx);
 198         }
 199 }
 200
 201 void ieee80211_ba_session_work(struct work_struct *work)
 202 {
 203         struct sta_info *sta =
 204                 container_of(work, struct sta_info, ampdu_mlme.work);
 205         struct tid_ampdu_tx *tid_tx;
 206         int tid;
 207
 208         /*
 209          * When this flag is set, new sessions should be
 210          * blocked, and existing sessions will be torn
 211          * down by the code that set the flag, so this
 212          * need not run.
 213          */
 214         if (test_sta_flag(sta, WLAN_STA_BLOCK_BA))
 215                 return;
 216
 217         mutex_lock(&sta->ampdu_mlme.mtx);
 218         for (tid = 0; tid < STA_TID_NUM; tid++) {
 219                 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 220                         ___ieee80211_stop_rx_ba_session(
 221                                 sta, tid, WLAN_BACK_RECIPIENT,
 222                                 WLAN_REASON_QSTA_TIMEOUT, true);
 223
 224                 if (test_and_clear_bit(tid,
 225                                        sta->ampdu_mlme.tid_rx_stop_requested))
 226                         ___ieee80211_stop_rx_ba_session(
 227                                 sta, tid, WLAN_BACK_RECIPIENT,
 228                                 WLAN_REASON_UNSPECIFIED, true);
 229
 230                 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
 231                 if (tid_tx) {
 232                         /*
 233                          * Assign it over to the normal tid_tx array
 234                          * where it "goes live".
 235                          */
 236                         spin_lock_bh(&sta->lock);
 237
 238                         sta->ampdu_mlme.tid_start_tx[tid] = NULL;
 239                         /* could there be a race? */
 240                         if (sta->ampdu_mlme.tid_tx[tid])
 241                                 kfree(tid_tx);
 242                         else
 243                                 ieee80211_assign_tid_tx(sta, tid, tid_tx);
 244                         spin_unlock_bh(&sta->lock);
 245
 246                         ieee80211_tx_ba_session_handle_start(sta, tid);
 247                         continue;
 248                 }
 249
 250                 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 251                 if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 252                                                  &tid_tx->state))
 253                         ___ieee80211_stop_tx_ba_session(sta, tid,
 254                                                         WLAN_BACK_INITIATOR,
 255                                                         true);
 256         }
 257         mutex_unlock(&sta->ampdu_mlme.mtx);
 258 }
 259
 260 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
 261                           const u8 *da, u16 tid,
 262                           u16 initiator, u16 reason_code)
 263 {
 264         struct ieee80211_local *local = sdata->local;
 265         struct sk_buff *skb;
 266         struct ieee80211_mgmt *mgmt;
 267         u16 params;
 268
 269         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 270         if (!skb)
 271                 return;
 272
 273         skb_reserve(skb, local->hw.extra_tx_headroom);
 274         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 275         memset(mgmt, 0, 24);
 276         memcpy(mgmt->da, da, ETH_ALEN);
 277         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 278         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 279             sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
 280             sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
 281                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 282         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 283                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 284
 285         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 286                                           IEEE80211_STYPE_ACTION);
 287
 288         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 289
 290         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 291         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 292         params = (u16)(initiator << 11);        /* bit 11 initiator */
 293         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 294
 295         mgmt->u.action.u.delba.params = cpu_to_le16(params);
 296         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 297
 298         ieee80211_tx_skb(sdata, skb);
 299 }
 300
 301 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 302                              struct sta_info *sta,
 303                              struct ieee80211_mgmt *mgmt, size_t len)
 304 {
 305         u16 tid, params;
 306         u16 initiator;
 307
 308         params = le16_to_cpu(mgmt->u.action.u.delba.params);
 309         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 310         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 311
 312 #ifdef CONFIG_MAC80211_HT_DEBUG
 313         if (net_ratelimit())
 314                 printk(KERN_DEBUG "delba from %pM (%s) tid %d reason code %d\n",
 315                         mgmt->sa, initiator ? "initiator" : "recipient", tid,
 316                         le16_to_cpu(mgmt->u.action.u.delba.reason_code));
 317 #endif /* CONFIG_MAC80211_HT_DEBUG */
 318
 319         if (initiator == WLAN_BACK_INITIATOR)
 320                 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
 321                                                true);
 322         else
 323                 __ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
 324                                                true);
 325 }
 326
 327 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
 328                                enum ieee80211_smps_mode smps, const u8 *da,
 329                                const u8 *bssid)
 330 {
 331         struct ieee80211_local *local = sdata->local;
 332         struct sk_buff *skb;
 333         struct ieee80211_mgmt *action_frame;
 334
 335         /* 27 = header + category + action + smps mode */
 336         skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
 337         if (!skb)
 338                 return -ENOMEM;
 339
 340         skb_reserve(skb, local->hw.extra_tx_headroom);
 341         action_frame = (void *)skb_put(skb, 27);
 342         memcpy(action_frame->da, da, ETH_ALEN);
 343         memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
 344         memcpy(action_frame->bssid, bssid, ETH_ALEN);
 345         action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 346                                                   IEEE80211_STYPE_ACTION);
 347         action_frame->u.action.category = WLAN_CATEGORY_HT;
 348         action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
 349         switch (smps) {
 350         case IEEE80211_SMPS_AUTOMATIC:
 351         case IEEE80211_SMPS_NUM_MODES:
 352                 WARN_ON(1);
 353         case IEEE80211_SMPS_OFF:
 354                 action_frame->u.action.u.ht_smps.smps_control =
 355                                 WLAN_HT_SMPS_CONTROL_DISABLED;
 356                 break;
 357         case IEEE80211_SMPS_STATIC:
 358                 action_frame->u.action.u.ht_smps.smps_control =
 359                                 WLAN_HT_SMPS_CONTROL_STATIC;
 360                 break;
 361         case IEEE80211_SMPS_DYNAMIC:
 362                 action_frame->u.action.u.ht_smps.smps_control =
 363                                 WLAN_HT_SMPS_CONTROL_DYNAMIC;
 364                 break;
 365         }
 366
 367         /* we'll do more on status of this frame */
 368         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 369         ieee80211_tx_skb(sdata, skb);
 370
 371         return 0;
 372 }
 373
 374 void ieee80211_request_smps_work(struct work_struct *work)
 375 {
 376         struct ieee80211_sub_if_data *sdata =
 377                 container_of(work, struct ieee80211_sub_if_data,
 378                              u.mgd.request_smps_work);
 379
 380         mutex_lock(&sdata->u.mgd.mtx);
 381         __ieee80211_request_smps(sdata, sdata->u.mgd.driver_smps_mode);
 382         mutex_unlock(&sdata->u.mgd.mtx);
 383 }
 384
 385 void ieee80211_request_smps(struct ieee80211_vif *vif,
 386                             enum ieee80211_smps_mode smps_mode)
 387 {
 388         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 389
 390         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
 391                 return;
 392
 393         if (WARN_ON(smps_mode == IEEE80211_SMPS_OFF))
 394                 smps_mode = IEEE80211_SMPS_AUTOMATIC;
 395
 396         sdata->u.mgd.driver_smps_mode = smps_mode;
 397
 398         ieee80211_queue_work(&sdata->local->hw,
 399                              &sdata->u.mgd.request_smps_work);
 400 }
 401 /* this might change ... don't want non-open drivers using it */
 402 EXPORT_SYMBOL_GPL(ieee80211_request_smps);