LXR linux/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 <linux/export.h>
  18#include <net/mac80211.h>
  19#include "ieee80211_i.h"
  20#include "rate.h"
  21
  22static void __check_htcap_disable(struct ieee80211_ht_cap *ht_capa,
  23                                  struct ieee80211_ht_cap *ht_capa_mask,
  24                                  struct ieee80211_sta_ht_cap *ht_cap,
  25                                  u16 flag)
  26{
  27        __le16 le_flag = cpu_to_le16(flag);
  28        if (ht_capa_mask->cap_info & le_flag) {
  29                if (!(ht_capa->cap_info & le_flag))
  30                        ht_cap->cap &= ~flag;
  31        }
  32}
  33
  34void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
  35                                     struct ieee80211_sta_ht_cap *ht_cap)
  36{
  37        struct ieee80211_ht_cap *ht_capa, *ht_capa_mask;
  38        u8 *scaps, *smask;
  39        int i;
  40
  41        if (!ht_cap->ht_supported)
  42                return;
  43
  44        switch (sdata->vif.type) {
  45        case NL80211_IFTYPE_STATION:
  46                ht_capa = &sdata->u.mgd.ht_capa;
  47                ht_capa_mask = &sdata->u.mgd.ht_capa_mask;
  48                break;
  49        case NL80211_IFTYPE_ADHOC:
  50                ht_capa = &sdata->u.ibss.ht_capa;
  51                ht_capa_mask = &sdata->u.ibss.ht_capa_mask;
  52                break;
  53        default:
  54                WARN_ON_ONCE(1);
  55                return;
  56        }
  57
  58        scaps = (u8 *)(&ht_capa->mcs.rx_mask);
  59        smask = (u8 *)(&ht_capa_mask->mcs.rx_mask);
  60
  61        /* NOTE:  If you add more over-rides here, update register_hw
  62         * ht_capa_mod_msk logic in main.c as well.
  63         * And, if this method can ever change ht_cap.ht_supported, fix
  64         * the check in ieee80211_add_ht_ie.
  65         */
  66
  67        /* check for HT over-rides, MCS rates first. */
  68        for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
  69                u8 m = smask[i];
  70                ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
  71                /* Add back rates that are supported */
  72                ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
  73        }
  74
  75        /* Force removal of HT-40 capabilities? */
  76        __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
  77                              IEEE80211_HT_CAP_SUP_WIDTH_20_40);
  78        __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
  79                              IEEE80211_HT_CAP_SGI_40);
  80
  81        /* Allow user to disable SGI-20 (SGI-40 is handled above) */
  82        __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
  83                              IEEE80211_HT_CAP_SGI_20);
  84
  85        /* Allow user to disable the max-AMSDU bit. */
  86        __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
  87                              IEEE80211_HT_CAP_MAX_AMSDU);
  88
  89        /* Allow user to decrease AMPDU factor */
  90        if (ht_capa_mask->ampdu_params_info &
  91            IEEE80211_HT_AMPDU_PARM_FACTOR) {
  92                u8 n = ht_capa->ampdu_params_info &
  93                       IEEE80211_HT_AMPDU_PARM_FACTOR;
  94                if (n < ht_cap->ampdu_factor)
  95                        ht_cap->ampdu_factor = n;
  96        }
  97
  98        /* Allow the user to increase AMPDU density. */
  99        if (ht_capa_mask->ampdu_params_info &
 100            IEEE80211_HT_AMPDU_PARM_DENSITY) {
 101                u8 n = (ht_capa->ampdu_params_info &
 102                        IEEE80211_HT_AMPDU_PARM_DENSITY)
 103                        >> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
 104                if (n > ht_cap->ampdu_density)
 105                        ht_cap->ampdu_density = n;
 106        }
 107}
 108
 109
 110bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
 111                                       struct ieee80211_supported_band *sband,
 112                                       const struct ieee80211_ht_cap *ht_cap_ie,
 113                                       struct sta_info *sta)
 114{
 115        struct ieee80211_sta_ht_cap ht_cap, own_cap;
 116        u8 ampdu_info, tx_mcs_set_cap;
 117        int i, max_tx_streams;
 118        bool changed;
 119        enum ieee80211_sta_rx_bandwidth bw;
 120        enum ieee80211_smps_mode smps_mode;
 121
 122        memset(&ht_cap, 0, sizeof(ht_cap));
 123
 124        if (!ht_cap_ie || !sband->ht_cap.ht_supported)
 125                goto apply;
 126
 127        ht_cap.ht_supported = true;
 128
 129        own_cap = sband->ht_cap;
 130
 131        /*
 132         * If user has specified capability over-rides, take care
 133         * of that if the station we're setting up is the AP that
 134         * we advertised a restricted capability set to. Override
 135         * our own capabilities and then use those below.
 136         */
 137        if ((sdata->vif.type == NL80211_IFTYPE_STATION ||
 138             sdata->vif.type == NL80211_IFTYPE_ADHOC) &&
 139            !test_sta_flag(sta, WLAN_STA_TDLS_PEER))
 140                ieee80211_apply_htcap_overrides(sdata, &own_cap);
 141
 142        /*
 143         * The bits listed in this expression should be
 144         * the same for the peer and us, if the station
 145         * advertises more then we can't use those thus
 146         * we mask them out.
 147         */
 148        ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) &
 149                (own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING |
 150                                 IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
 151                                 IEEE80211_HT_CAP_GRN_FLD |
 152                                 IEEE80211_HT_CAP_SGI_20 |
 153                                 IEEE80211_HT_CAP_SGI_40 |
 154                                 IEEE80211_HT_CAP_DSSSCCK40));
 155
 156        /*
 157         * The STBC bits are asymmetric -- if we don't have
 158         * TX then mask out the peer's RX and vice versa.
 159         */
 160        if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC))
 161                ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC;
 162        if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC))
 163                ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC;
 164
 165        ampdu_info = ht_cap_ie->ampdu_params_info;
 166        ht_cap.ampdu_factor =
 167                ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
 168        ht_cap.ampdu_density =
 169                (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
 170
 171        /* own MCS TX capabilities */
 172        tx_mcs_set_cap = own_cap.mcs.tx_params;
 173
 174        /* Copy peer MCS TX capabilities, the driver might need them. */
 175        ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params;
 176
 177        /* can we TX with MCS rates? */
 178        if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
 179                goto apply;
 180
 181        /* Counting from 0, therefore +1 */
 182        if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
 183                max_tx_streams =
 184                        ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
 185                                >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
 186        else
 187                max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
 188
 189        /*
 190         * 802.11n-2009 20.3.5 / 20.6 says:
 191         * - indices 0 to 7 and 32 are single spatial stream
 192         * - 8 to 31 are multiple spatial streams using equal modulation
 193         *   [8..15 for two streams, 16..23 for three and 24..31 for four]
 194         * - remainder are multiple spatial streams using unequal modulation
 195         */
 196        for (i = 0; i < max_tx_streams; i++)
 197                ht_cap.mcs.rx_mask[i] =
 198                        own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
 199
 200        if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
 201                for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
 202                     i < IEEE80211_HT_MCS_MASK_LEN; i++)
 203                        ht_cap.mcs.rx_mask[i] =
 204                                own_cap.mcs.rx_mask[i] &
 205                                        ht_cap_ie->mcs.rx_mask[i];
 206
 207        /* handle MCS rate 32 too */
 208        if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
 209                ht_cap.mcs.rx_mask[32/8] |= 1;
 210
 211 apply:
 212        changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
 213
 214        memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
 215
 216        switch (sdata->vif.bss_conf.chandef.width) {
 217        default:
 218                WARN_ON_ONCE(1);
 219                /* fall through */
 220        case NL80211_CHAN_WIDTH_20_NOHT:
 221        case NL80211_CHAN_WIDTH_20:
 222                bw = IEEE80211_STA_RX_BW_20;
 223                break;
 224        case NL80211_CHAN_WIDTH_40:
 225        case NL80211_CHAN_WIDTH_80:
 226        case NL80211_CHAN_WIDTH_80P80:
 227        case NL80211_CHAN_WIDTH_160:
 228                bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
 229                                IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
 230                break;
 231        }
 232
 233        if (bw != sta->sta.bandwidth)
 234                changed = true;
 235        sta->sta.bandwidth = bw;
 236
 237        sta->cur_max_bandwidth =
 238                ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
 239                                IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
 240
 241        switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
 242                        >> IEEE80211_HT_CAP_SM_PS_SHIFT) {
 243        case WLAN_HT_CAP_SM_PS_INVALID:
 244        case WLAN_HT_CAP_SM_PS_STATIC:
 245                smps_mode = IEEE80211_SMPS_STATIC;
 246                break;
 247        case WLAN_HT_CAP_SM_PS_DYNAMIC:
 248                smps_mode = IEEE80211_SMPS_DYNAMIC;
 249                break;
 250        case WLAN_HT_CAP_SM_PS_DISABLED:
 251                smps_mode = IEEE80211_SMPS_OFF;
 252                break;
 253        }
 254
 255        if (smps_mode != sta->sta.smps_mode)
 256                changed = true;
 257        sta->sta.smps_mode = smps_mode;
 258
 259        return changed;
 260}
 261
 262void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
 263                                         enum ieee80211_agg_stop_reason reason)
 264{
 265        int i;
 266
 267        cancel_work_sync(&sta->ampdu_mlme.work);
 268
 269        for (i = 0; i <  IEEE80211_NUM_TIDS; i++) {
 270                __ieee80211_stop_tx_ba_session(sta, i, reason);
 271                __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
 272                                               WLAN_REASON_QSTA_LEAVE_QBSS,
 273                                               reason != AGG_STOP_DESTROY_STA &&
 274                                               reason != AGG_STOP_PEER_REQUEST);
 275        }
 276}
 277
 278void ieee80211_ba_session_work(struct work_struct *work)
 279{
 280        struct sta_info *sta =
 281                container_of(work, struct sta_info, ampdu_mlme.work);
 282        struct tid_ampdu_tx *tid_tx;
 283        int tid;
 284
 285        /*
 286         * When this flag is set, new sessions should be
 287         * blocked, and existing sessions will be torn
 288         * down by the code that set the flag, so this
 289         * need not run.
 290         */
 291        if (test_sta_flag(sta, WLAN_STA_BLOCK_BA))
 292                return;
 293
 294        mutex_lock(&sta->ampdu_mlme.mtx);
 295        for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
 296                if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 297                        ___ieee80211_stop_rx_ba_session(
 298                                sta, tid, WLAN_BACK_RECIPIENT,
 299                                WLAN_REASON_QSTA_TIMEOUT, true);
 300
 301                if (test_and_clear_bit(tid,
 302                                       sta->ampdu_mlme.tid_rx_stop_requested))
 303                        ___ieee80211_stop_rx_ba_session(
 304                                sta, tid, WLAN_BACK_RECIPIENT,
 305                                WLAN_REASON_UNSPECIFIED, true);
 306
 307                spin_lock_bh(&sta->lock);
 308
 309                tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
 310                if (tid_tx) {
 311                        /*
 312                         * Assign it over to the normal tid_tx array
 313                         * where it "goes live".
 314                         */
 315
 316                        sta->ampdu_mlme.tid_start_tx[tid] = NULL;
 317                        /* could there be a race? */
 318                        if (sta->ampdu_mlme.tid_tx[tid])
 319                                kfree(tid_tx);
 320                        else
 321                                ieee80211_assign_tid_tx(sta, tid, tid_tx);
 322                        spin_unlock_bh(&sta->lock);
 323
 324                        ieee80211_tx_ba_session_handle_start(sta, tid);
 325                        continue;
 326                }
 327                spin_unlock_bh(&sta->lock);
 328
 329                tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 330                if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 331                                                 &tid_tx->state))
 332                        ___ieee80211_stop_tx_ba_session(sta, tid,
 333                                                        AGG_STOP_LOCAL_REQUEST);
 334        }
 335        mutex_unlock(&sta->ampdu_mlme.mtx);
 336}
 337
 338void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
 339                          const u8 *da, u16 tid,
 340                          u16 initiator, u16 reason_code)
 341{
 342        struct ieee80211_local *local = sdata->local;
 343        struct sk_buff *skb;
 344        struct ieee80211_mgmt *mgmt;
 345        u16 params;
 346
 347        skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 348        if (!skb)
 349                return;
 350
 351        skb_reserve(skb, local->hw.extra_tx_headroom);
 352        mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 353        memset(mgmt, 0, 24);
 354        memcpy(mgmt->da, da, ETH_ALEN);
 355        memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 356        if (sdata->vif.type == NL80211_IFTYPE_AP ||
 357            sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
 358            sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
 359                memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 360        else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 361                memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 362        else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
 363                memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
 364
 365        mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 366                                          IEEE80211_STYPE_ACTION);
 367
 368        skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 369
 370        mgmt->u.action.category = WLAN_CATEGORY_BACK;
 371        mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 372        params = (u16)(initiator << 11);        /* bit 11 initiator */
 373        params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 374
 375        mgmt->u.action.u.delba.params = cpu_to_le16(params);
 376        mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 377
 378        ieee80211_tx_skb_tid(sdata, skb, tid);
 379}
 380
 381void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 382                             struct sta_info *sta,
 383                             struct ieee80211_mgmt *mgmt, size_t len)
 384{
 385        u16 tid, params;
 386        u16 initiator;
 387
 388        params = le16_to_cpu(mgmt->u.action.u.delba.params);
 389        tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 390        initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 391
 392        ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
 393                           mgmt->sa, initiator ? "initiator" : "recipient",
 394                           tid,
 395                           le16_to_cpu(mgmt->u.action.u.delba.reason_code));
 396
 397        if (initiator == WLAN_BACK_INITIATOR)
 398                __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
 399                                               true);
 400        else
 401                __ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
 402}
 403
 404int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
 405                               enum ieee80211_smps_mode smps, const u8 *da,
 406                               const u8 *bssid)
 407{
 408        struct ieee80211_local *local = sdata->local;
 409        struct sk_buff *skb;
 410        struct ieee80211_mgmt *action_frame;
 411
 412        /* 27 = header + category + action + smps mode */
 413        skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
 414        if (!skb)
 415                return -ENOMEM;
 416
 417        skb_reserve(skb, local->hw.extra_tx_headroom);
 418        action_frame = (void *)skb_put(skb, 27);
 419        memcpy(action_frame->da, da, ETH_ALEN);
 420        memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
 421        memcpy(action_frame->bssid, bssid, ETH_ALEN);
 422        action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 423                                                  IEEE80211_STYPE_ACTION);
 424        action_frame->u.action.category = WLAN_CATEGORY_HT;
 425        action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
 426        switch (smps) {
 427        case IEEE80211_SMPS_AUTOMATIC:
 428        case IEEE80211_SMPS_NUM_MODES:
 429                WARN_ON(1);
 430        case IEEE80211_SMPS_OFF:
 431                action_frame->u.action.u.ht_smps.smps_control =
 432                                WLAN_HT_SMPS_CONTROL_DISABLED;
 433                break;
 434        case IEEE80211_SMPS_STATIC:
 435                action_frame->u.action.u.ht_smps.smps_control =
 436                                WLAN_HT_SMPS_CONTROL_STATIC;
 437                break;
 438        case IEEE80211_SMPS_DYNAMIC:
 439                action_frame->u.action.u.ht_smps.smps_control =
 440                                WLAN_HT_SMPS_CONTROL_DYNAMIC;
 441                break;
 442        }
 443
 444        /* we'll do more on status of this frame */
 445        IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 446        ieee80211_tx_skb(sdata, skb);
 447
 448        return 0;
 449}
 450
 451void ieee80211_request_smps_work(struct work_struct *work)
 452{
 453        struct ieee80211_sub_if_data *sdata =
 454                container_of(work, struct ieee80211_sub_if_data,
 455                             u.mgd.request_smps_work);
 456
 457        sdata_lock(sdata);
 458        __ieee80211_request_smps(sdata, sdata->u.mgd.driver_smps_mode);
 459        sdata_unlock(sdata);
 460}
 461
 462void ieee80211_request_smps(struct ieee80211_vif *vif,
 463                            enum ieee80211_smps_mode smps_mode)
 464{
 465        struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 466
 467        if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
 468                return;
 469
 470        if (WARN_ON(smps_mode == IEEE80211_SMPS_OFF))
 471                smps_mode = IEEE80211_SMPS_AUTOMATIC;
 472
 473        if (sdata->u.mgd.driver_smps_mode == smps_mode)
 474                return;
 475
 476        sdata->u.mgd.driver_smps_mode = smps_mode;
 477
 478        ieee80211_queue_work(&sdata->local->hw,
 479                             &sdata->u.mgd.request_smps_work);
 480}
 481/* this might change ... don't want non-open drivers using it */
 482EXPORT_SYMBOL_GPL(ieee80211_request_smps);
 483