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 void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
  22                                        struct ieee80211_ht_cap *ht_cap_ie,
  23                                        struct ieee80211_sta_ht_cap *ht_cap)
  24 {
  25         u8 ampdu_info, tx_mcs_set_cap;
  26         int i, max_tx_streams;
  27
  28         BUG_ON(!ht_cap);
  29
  30         memset(ht_cap, 0, sizeof(*ht_cap));
  31
  32         if (!ht_cap_ie || !sband->ht_cap.ht_supported)
  33                 return;
  34
  35         ht_cap->ht_supported = true;
  36
  37         /*
  38          * The bits listed in this expression should be
  39          * the same for the peer and us, if the station
  40          * advertises more then we can't use those thus
  41          * we mask them out.
  42          */
  43         ht_cap->cap = le16_to_cpu(ht_cap_ie->cap_info) &
  44                 (sband->ht_cap.cap |
  45                  ~(IEEE80211_HT_CAP_LDPC_CODING |
  46                    IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
  47                    IEEE80211_HT_CAP_GRN_FLD |
  48                    IEEE80211_HT_CAP_SGI_20 |
  49                    IEEE80211_HT_CAP_SGI_40 |
  50                    IEEE80211_HT_CAP_DSSSCCK40));
  51         /*
  52          * The STBC bits are asymmetric -- if we don't have
  53          * TX then mask out the peer's RX and vice versa.
  54          */
  55         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_TX_STBC))
  56                 ht_cap->cap &= ~IEEE80211_HT_CAP_RX_STBC;
  57         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_RX_STBC))
  58                 ht_cap->cap &= ~IEEE80211_HT_CAP_TX_STBC;
  59
  60         ampdu_info = ht_cap_ie->ampdu_params_info;
  61         ht_cap->ampdu_factor =
  62                 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
  63         ht_cap->ampdu_density =
  64                 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
  65
  66         /* own MCS TX capabilities */
  67         tx_mcs_set_cap = sband->ht_cap.mcs.tx_params;
  68
  69         /* Copy peer MCS TX capabilities, the driver might need them. */
  70         ht_cap->mcs.tx_params = ht_cap_ie->mcs.tx_params;
  71
  72         /* can we TX with MCS rates? */
  73         if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
  74                 return;
  75
  76         /* Counting from 0, therefore +1 */
  77         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
  78                 max_tx_streams =
  79                         ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
  80                                 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
  81         else
  82                 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
  83
  84         /*
  85          * 802.11n-2009 20.3.5 / 20.6 says:
  86          * - indices 0 to 7 and 32 are single spatial stream
  87          * - 8 to 31 are multiple spatial streams using equal modulation
  88          *   [8..15 for two streams, 16..23 for three and 24..31 for four]
  89          * - remainder are multiple spatial streams using unequal modulation
  90          */
  91         for (i = 0; i < max_tx_streams; i++)
  92                 ht_cap->mcs.rx_mask[i] =
  93                         sband->ht_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
  94
  95         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
  96                 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
  97                      i < IEEE80211_HT_MCS_MASK_LEN; i++)
  98                         ht_cap->mcs.rx_mask[i] =
  99                                 sband->ht_cap.mcs.rx_mask[i] &
 100                                         ht_cap_ie->mcs.rx_mask[i];
 101
 102         /* handle MCS rate 32 too */
 103         if (sband->ht_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
 104                 ht_cap->mcs.rx_mask[32/8] |= 1;
 105 }
 106
 107 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx)
 108 {
 109         int i;
 110
 111         cancel_work_sync(&sta->ampdu_mlme.work);
 112
 113         for (i = 0; i <  STA_TID_NUM; i++) {
 114                 __ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR, tx);
 115                 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
 116                                                WLAN_REASON_QSTA_LEAVE_QBSS, tx);
 117         }
 118 }
 119
 120 void ieee80211_ba_session_work(struct work_struct *work)
 121 {
 122         struct sta_info *sta =
 123                 container_of(work, struct sta_info, ampdu_mlme.work);
 124         struct tid_ampdu_tx *tid_tx;
 125         int tid;
 126
 127         /*
 128          * When this flag is set, new sessions should be
 129          * blocked, and existing sessions will be torn
 130          * down by the code that set the flag, so this
 131          * need not run.
 132          */
 133         if (test_sta_flags(sta, WLAN_STA_BLOCK_BA))
 134                 return;
 135
 136         mutex_lock(&sta->ampdu_mlme.mtx);
 137         for (tid = 0; tid < STA_TID_NUM; tid++) {
 138                 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 139                         ___ieee80211_stop_rx_ba_session(
 140                                 sta, tid, WLAN_BACK_RECIPIENT,
 141                                 WLAN_REASON_QSTA_TIMEOUT, true);
 142
 143                 if (test_and_clear_bit(tid,
 144                                        sta->ampdu_mlme.tid_rx_stop_requested))
 145                         ___ieee80211_stop_rx_ba_session(
 146                                 sta, tid, WLAN_BACK_RECIPIENT,
 147                                 WLAN_REASON_UNSPECIFIED, true);
 148
 149                 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
 150                 if (tid_tx) {
 151                         /*
 152                          * Assign it over to the normal tid_tx array
 153                          * where it "goes live".
 154                          */
 155                         spin_lock_bh(&sta->lock);
 156
 157                         sta->ampdu_mlme.tid_start_tx[tid] = NULL;
 158                         /* could there be a race? */
 159                         if (sta->ampdu_mlme.tid_tx[tid])
 160                                 kfree(tid_tx);
 161                         else
 162                                 ieee80211_assign_tid_tx(sta, tid, tid_tx);
 163                         spin_unlock_bh(&sta->lock);
 164
 165                         ieee80211_tx_ba_session_handle_start(sta, tid);
 166                         continue;
 167                 }
 168
 169                 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 170                 if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 171                                                  &tid_tx->state))
 172                         ___ieee80211_stop_tx_ba_session(sta, tid,
 173                                                         WLAN_BACK_INITIATOR,
 174                                                         true);
 175         }
 176         mutex_unlock(&sta->ampdu_mlme.mtx);
 177 }
 178
 179 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
 180                           const u8 *da, u16 tid,
 181                           u16 initiator, u16 reason_code)
 182 {
 183         struct ieee80211_local *local = sdata->local;
 184         struct sk_buff *skb;
 185         struct ieee80211_mgmt *mgmt;
 186         u16 params;
 187
 188         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 189
 190         if (!skb) {
 191                 printk(KERN_ERR "%s: failed to allocate buffer "
 192                                         "for delba frame\n", sdata->name);
 193                 return;
 194         }
 195
 196         skb_reserve(skb, local->hw.extra_tx_headroom);
 197         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 198         memset(mgmt, 0, 24);
 199         memcpy(mgmt->da, da, ETH_ALEN);
 200         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 201         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 202             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 203                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 204         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 205                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 206
 207         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 208                                           IEEE80211_STYPE_ACTION);
 209
 210         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 211
 212         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 213         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 214         params = (u16)(initiator << 11);        /* bit 11 initiator */
 215         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 216
 217         mgmt->u.action.u.delba.params = cpu_to_le16(params);
 218         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 219
 220         ieee80211_tx_skb(sdata, skb);
 221 }
 222
 223 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 224                              struct sta_info *sta,
 225                              struct ieee80211_mgmt *mgmt, size_t len)
 226 {
 227         u16 tid, params;
 228         u16 initiator;
 229
 230         params = le16_to_cpu(mgmt->u.action.u.delba.params);
 231         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 232         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 233
 234 #ifdef CONFIG_MAC80211_HT_DEBUG
 235         if (net_ratelimit())
 236                 printk(KERN_DEBUG "delba from %pM (%s) tid %d reason code %d\n",
 237                         mgmt->sa, initiator ? "initiator" : "recipient", tid,
 238                         le16_to_cpu(mgmt->u.action.u.delba.reason_code));
 239 #endif /* CONFIG_MAC80211_HT_DEBUG */
 240
 241         if (initiator == WLAN_BACK_INITIATOR)
 242                 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
 243                                                true);
 244         else
 245                 __ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
 246                                                true);
 247 }
 248
 249 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
 250                                enum ieee80211_smps_mode smps, const u8 *da,
 251                                const u8 *bssid)
 252 {
 253         struct ieee80211_local *local = sdata->local;
 254         struct sk_buff *skb;
 255         struct ieee80211_mgmt *action_frame;
 256
 257         /* 27 = header + category + action + smps mode */
 258         skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
 259         if (!skb)
 260                 return -ENOMEM;
 261
 262         skb_reserve(skb, local->hw.extra_tx_headroom);
 263         action_frame = (void *)skb_put(skb, 27);
 264         memcpy(action_frame->da, da, ETH_ALEN);
 265         memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
 266         memcpy(action_frame->bssid, bssid, ETH_ALEN);
 267         action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 268                                                   IEEE80211_STYPE_ACTION);
 269         action_frame->u.action.category = WLAN_CATEGORY_HT;
 270         action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
 271         switch (smps) {
 272         case IEEE80211_SMPS_AUTOMATIC:
 273         case IEEE80211_SMPS_NUM_MODES:
 274                 WARN_ON(1);
 275         case IEEE80211_SMPS_OFF:
 276                 action_frame->u.action.u.ht_smps.smps_control =
 277                                 WLAN_HT_SMPS_CONTROL_DISABLED;
 278                 break;
 279         case IEEE80211_SMPS_STATIC:
 280                 action_frame->u.action.u.ht_smps.smps_control =
 281                                 WLAN_HT_SMPS_CONTROL_STATIC;
 282                 break;
 283         case IEEE80211_SMPS_DYNAMIC:
 284                 action_frame->u.action.u.ht_smps.smps_control =
 285                                 WLAN_HT_SMPS_CONTROL_DYNAMIC;
 286                 break;
 287         }
 288
 289         /* we'll do more on status of this frame */
 290         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 291         ieee80211_tx_skb(sdata, skb);
 292
 293         return 0;
 294 }
 295
 296 void ieee80211_request_smps_work(struct work_struct *work)
 297 {
 298         struct ieee80211_sub_if_data *sdata =
 299                 container_of(work, struct ieee80211_sub_if_data,
 300                              u.mgd.request_smps_work);
 301
 302         mutex_lock(&sdata->u.mgd.mtx);
 303         __ieee80211_request_smps(sdata, sdata->u.mgd.driver_smps_mode);
 304         mutex_unlock(&sdata->u.mgd.mtx);
 305 }
 306
 307 void ieee80211_request_smps(struct ieee80211_vif *vif,
 308                             enum ieee80211_smps_mode smps_mode)
 309 {
 310         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 311
 312         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
 313                 return;
 314
 315         if (WARN_ON(smps_mode == IEEE80211_SMPS_OFF))
 316                 smps_mode = IEEE80211_SMPS_AUTOMATIC;
 317
 318         sdata->u.mgd.driver_smps_mode = smps_mode;
 319
 320         ieee80211_queue_work(&sdata->local->hw,
 321                              &sdata->u.mgd.request_smps_work);
 322 }
 323 /* this might change ... don't want non-open drivers using it */
 324 EXPORT_SYMBOL_GPL(ieee80211_request_smps);