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