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_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 34 static void __check_htcap_enable(struct ieee80211_ht_cap *ht_capa, 35 struct ieee80211_ht_cap *ht_capa_mask, 36 struct ieee80211_sta_ht_cap *ht_cap, 37 u16 flag) 38 { 39 __le16 le_flag = cpu_to_le16(flag); 40 41 if ((ht_capa_mask->cap_info & le_flag) && 42 (ht_capa->cap_info & le_flag)) 43 ht_cap->cap |= flag; 44 } 45 46 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata, 47 struct ieee80211_sta_ht_cap *ht_cap) 48 { 49 struct ieee80211_ht_cap *ht_capa, *ht_capa_mask; 50 u8 *scaps, *smask; 51 int i; 52 53 if (!ht_cap->ht_supported) 54 return; 55 56 switch (sdata->vif.type) { 57 case NL80211_IFTYPE_STATION: 58 ht_capa = &sdata->u.mgd.ht_capa; 59 ht_capa_mask = &sdata->u.mgd.ht_capa_mask; 60 break; 61 case NL80211_IFTYPE_ADHOC: 62 ht_capa = &sdata->u.ibss.ht_capa; 63 ht_capa_mask = &sdata->u.ibss.ht_capa_mask; 64 break; 65 default: 66 WARN_ON_ONCE(1); 67 return; 68 } 69 70 scaps = (u8 *)(&ht_capa->mcs.rx_mask); 71 smask = (u8 *)(&ht_capa_mask->mcs.rx_mask); 72 73 /* NOTE: If you add more over-rides here, update register_hw 74 * ht_capa_mod_mask logic in main.c as well. 75 * And, if this method can ever change ht_cap.ht_supported, fix 76 * the check in ieee80211_add_ht_ie. 77 */ 78 79 /* check for HT over-rides, MCS rates first. */ 80 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) { 81 u8 m = smask[i]; 82 ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */ 83 /* Add back rates that are supported */ 84 ht_cap->mcs.rx_mask[i] |= (m & scaps[i]); 85 } 86 87 /* Force removal of HT-40 capabilities? */ 88 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap, 89 IEEE80211_HT_CAP_SUP_WIDTH_20_40); 90 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap, 91 IEEE80211_HT_CAP_SGI_40); 92 93 /* Allow user to disable SGI-20 (SGI-40 is handled above) */ 94 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap, 95 IEEE80211_HT_CAP_SGI_20); 96 97 /* Allow user to disable the max-AMSDU bit. */ 98 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap, 99 IEEE80211_HT_CAP_MAX_AMSDU); 100 101 /* Allow user to disable LDPC */ 102 __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap, 103 IEEE80211_HT_CAP_LDPC_CODING); 104 105 /* Allow user to enable 40 MHz intolerant bit. */ 106 __check_htcap_enable(ht_capa, ht_capa_mask, ht_cap, 107 IEEE80211_HT_CAP_40MHZ_INTOLERANT); 108 109 /* Allow user to decrease AMPDU factor */ 110 if (ht_capa_mask->ampdu_params_info & 111 IEEE80211_HT_AMPDU_PARM_FACTOR) { 112 u8 n = ht_capa->ampdu_params_info & 113 IEEE80211_HT_AMPDU_PARM_FACTOR; 114 if (n < ht_cap->ampdu_factor) 115 ht_cap->ampdu_factor = n; 116 } 117 118 /* Allow the user to increase AMPDU density. */ 119 if (ht_capa_mask->ampdu_params_info & 120 IEEE80211_HT_AMPDU_PARM_DENSITY) { 121 u8 n = (ht_capa->ampdu_params_info & 122 IEEE80211_HT_AMPDU_PARM_DENSITY) 123 >> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT; 124 if (n > ht_cap->ampdu_density) 125 ht_cap->ampdu_density = n; 126 } 127 } 128 129 130 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata, 131 struct ieee80211_supported_band *sband, 132 const struct ieee80211_ht_cap *ht_cap_ie, 133 struct sta_info *sta) 134 { 135 struct ieee80211_sta_ht_cap ht_cap, own_cap; 136 u8 ampdu_info, tx_mcs_set_cap; 137 int i, max_tx_streams; 138 bool changed; 139 enum ieee80211_sta_rx_bandwidth bw; 140 enum ieee80211_smps_mode smps_mode; 141 142 memset(&ht_cap, 0, sizeof(ht_cap)); 143 144 if (!ht_cap_ie || !sband->ht_cap.ht_supported) 145 goto apply; 146 147 ht_cap.ht_supported = true; 148 149 own_cap = sband->ht_cap; 150 151 /* 152 * If user has specified capability over-rides, take care 153 * of that if the station we're setting up is the AP that 154 * we advertised a restricted capability set to. Override 155 * our own capabilities and then use those below. 156 */ 157 if ((sdata->vif.type == NL80211_IFTYPE_STATION || 158 sdata->vif.type == NL80211_IFTYPE_ADHOC) && 159 !test_sta_flag(sta, WLAN_STA_TDLS_PEER)) 160 ieee80211_apply_htcap_overrides(sdata, &own_cap); 161 162 /* 163 * The bits listed in this expression should be 164 * the same for the peer and us, if the station 165 * advertises more then we can't use those thus 166 * we mask them out. 167 */ 168 ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) & 169 (own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING | 170 IEEE80211_HT_CAP_SUP_WIDTH_20_40 | 171 IEEE80211_HT_CAP_GRN_FLD | 172 IEEE80211_HT_CAP_SGI_20 | 173 IEEE80211_HT_CAP_SGI_40 | 174 IEEE80211_HT_CAP_DSSSCCK40)); 175 176 /* 177 * The STBC bits are asymmetric -- if we don't have 178 * TX then mask out the peer's RX and vice versa. 179 */ 180 if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC)) 181 ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC; 182 if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC)) 183 ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC; 184 185 ampdu_info = ht_cap_ie->ampdu_params_info; 186 ht_cap.ampdu_factor = 187 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR; 188 ht_cap.ampdu_density = 189 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2; 190 191 /* own MCS TX capabilities */ 192 tx_mcs_set_cap = own_cap.mcs.tx_params; 193 194 /* Copy peer MCS TX capabilities, the driver might need them. */ 195 ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params; 196 197 /* can we TX with MCS rates? */ 198 if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED)) 199 goto apply; 200 201 /* Counting from 0, therefore +1 */ 202 if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF) 203 max_tx_streams = 204 ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK) 205 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1; 206 else 207 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS; 208 209 /* 210 * 802.11n-2009 20.3.5 / 20.6 says: 211 * - indices 0 to 7 and 32 are single spatial stream 212 * - 8 to 31 are multiple spatial streams using equal modulation 213 * [8..15 for two streams, 16..23 for three and 24..31 for four] 214 * - remainder are multiple spatial streams using unequal modulation 215 */ 216 for (i = 0; i < max_tx_streams; i++) 217 ht_cap.mcs.rx_mask[i] = 218 own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i]; 219 220 if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION) 221 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE; 222 i < IEEE80211_HT_MCS_MASK_LEN; i++) 223 ht_cap.mcs.rx_mask[i] = 224 own_cap.mcs.rx_mask[i] & 225 ht_cap_ie->mcs.rx_mask[i]; 226 227 /* handle MCS rate 32 too */ 228 if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1) 229 ht_cap.mcs.rx_mask[32/8] |= 1; 230 231 apply: 232 changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap)); 233 234 memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap)); 235 236 switch (sdata->vif.bss_conf.chandef.width) { 237 default: 238 WARN_ON_ONCE(1); 239 /* fall through */ 240 case NL80211_CHAN_WIDTH_20_NOHT: 241 case NL80211_CHAN_WIDTH_20: 242 bw = IEEE80211_STA_RX_BW_20; 243 break; 244 case NL80211_CHAN_WIDTH_40: 245 case NL80211_CHAN_WIDTH_80: 246 case NL80211_CHAN_WIDTH_80P80: 247 case NL80211_CHAN_WIDTH_160: 248 bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ? 249 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20; 250 break; 251 } 252 253 if (bw != sta->sta.bandwidth) 254 changed = true; 255 sta->sta.bandwidth = bw; 256 257 sta->cur_max_bandwidth = 258 ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ? 259 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20; 260 261 switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS) 262 >> IEEE80211_HT_CAP_SM_PS_SHIFT) { 263 case WLAN_HT_CAP_SM_PS_INVALID: 264 case WLAN_HT_CAP_SM_PS_STATIC: 265 smps_mode = IEEE80211_SMPS_STATIC; 266 break; 267 case WLAN_HT_CAP_SM_PS_DYNAMIC: 268 smps_mode = IEEE80211_SMPS_DYNAMIC; 269 break; 270 case WLAN_HT_CAP_SM_PS_DISABLED: 271 smps_mode = IEEE80211_SMPS_OFF; 272 break; 273 } 274 275 if (smps_mode != sta->sta.smps_mode) 276 changed = true; 277 sta->sta.smps_mode = smps_mode; 278 279 return changed; 280 } 281 282 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, 283 enum ieee80211_agg_stop_reason reason) 284 { 285 int i; 286 287 cancel_work_sync(&sta->ampdu_mlme.work); 288 289 for (i = 0; i < IEEE80211_NUM_TIDS; i++) { 290 __ieee80211_stop_tx_ba_session(sta, i, reason); 291 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT, 292 WLAN_REASON_QSTA_LEAVE_QBSS, 293 reason != AGG_STOP_DESTROY_STA && 294 reason != AGG_STOP_PEER_REQUEST); 295 } 296 } 297 298 void ieee80211_ba_session_work(struct work_struct *work) 299 { 300 struct sta_info *sta = 301 container_of(work, struct sta_info, ampdu_mlme.work); 302 struct tid_ampdu_tx *tid_tx; 303 int tid; 304 305 /* 306 * When this flag is set, new sessions should be 307 * blocked, and existing sessions will be torn 308 * down by the code that set the flag, so this 309 * need not run. 310 */ 311 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) 312 return; 313 314 mutex_lock(&sta->ampdu_mlme.mtx); 315 for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) { 316 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired)) 317 ___ieee80211_stop_rx_ba_session( 318 sta, tid, WLAN_BACK_RECIPIENT, 319 WLAN_REASON_QSTA_TIMEOUT, true); 320 321 if (test_and_clear_bit(tid, 322 sta->ampdu_mlme.tid_rx_stop_requested)) 323 ___ieee80211_stop_rx_ba_session( 324 sta, tid, WLAN_BACK_RECIPIENT, 325 WLAN_REASON_UNSPECIFIED, true); 326 327 spin_lock_bh(&sta->lock); 328 329 tid_tx = sta->ampdu_mlme.tid_start_tx[tid]; 330 if (tid_tx) { 331 /* 332 * Assign it over to the normal tid_tx array 333 * where it "goes live". 334 */ 335 336 sta->ampdu_mlme.tid_start_tx[tid] = NULL; 337 /* could there be a race? */ 338 if (sta->ampdu_mlme.tid_tx[tid]) 339 kfree(tid_tx); 340 else 341 ieee80211_assign_tid_tx(sta, tid, tid_tx); 342 spin_unlock_bh(&sta->lock); 343 344 ieee80211_tx_ba_session_handle_start(sta, tid); 345 continue; 346 } 347 spin_unlock_bh(&sta->lock); 348 349 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 350 if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP, 351 &tid_tx->state)) 352 ___ieee80211_stop_tx_ba_session(sta, tid, 353 AGG_STOP_LOCAL_REQUEST); 354 } 355 mutex_unlock(&sta->ampdu_mlme.mtx); 356 } 357 358 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata, 359 const u8 *da, u16 tid, 360 u16 initiator, u16 reason_code) 361 { 362 struct ieee80211_local *local = sdata->local; 363 struct sk_buff *skb; 364 struct ieee80211_mgmt *mgmt; 365 u16 params; 366 367 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); 368 if (!skb) 369 return; 370 371 skb_reserve(skb, local->hw.extra_tx_headroom); 372 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24); 373 memset(mgmt, 0, 24); 374 memcpy(mgmt->da, da, ETH_ALEN); 375 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 376 if (sdata->vif.type == NL80211_IFTYPE_AP || 377 sdata->vif.type == NL80211_IFTYPE_AP_VLAN || 378 sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 379 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 380 else if (sdata->vif.type == NL80211_IFTYPE_STATION) 381 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); 382 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 383 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); 384 385 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 386 IEEE80211_STYPE_ACTION); 387 388 skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba)); 389 390 mgmt->u.action.category = WLAN_CATEGORY_BACK; 391 mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA; 392 params = (u16)(initiator << 11); /* bit 11 initiator */ 393 params |= (u16)(tid << 12); /* bit 15:12 TID number */ 394 395 mgmt->u.action.u.delba.params = cpu_to_le16(params); 396 mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code); 397 398 ieee80211_tx_skb(sdata, skb); 399 } 400 401 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata, 402 struct sta_info *sta, 403 struct ieee80211_mgmt *mgmt, size_t len) 404 { 405 u16 tid, params; 406 u16 initiator; 407 408 params = le16_to_cpu(mgmt->u.action.u.delba.params); 409 tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12; 410 initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11; 411 412 ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n", 413 mgmt->sa, initiator ? "initiator" : "recipient", 414 tid, 415 le16_to_cpu(mgmt->u.action.u.delba.reason_code)); 416 417 if (initiator == WLAN_BACK_INITIATOR) 418 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0, 419 true); 420 else 421 __ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST); 422 } 423 424 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata, 425 enum ieee80211_smps_mode smps, const u8 *da, 426 const u8 *bssid) 427 { 428 struct ieee80211_local *local = sdata->local; 429 struct sk_buff *skb; 430 struct ieee80211_mgmt *action_frame; 431 432 /* 27 = header + category + action + smps mode */ 433 skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom); 434 if (!skb) 435 return -ENOMEM; 436 437 skb_reserve(skb, local->hw.extra_tx_headroom); 438 action_frame = (void *)skb_put(skb, 27); 439 memcpy(action_frame->da, da, ETH_ALEN); 440 memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN); 441 memcpy(action_frame->bssid, bssid, ETH_ALEN); 442 action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 443 IEEE80211_STYPE_ACTION); 444 action_frame->u.action.category = WLAN_CATEGORY_HT; 445 action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS; 446 switch (smps) { 447 case IEEE80211_SMPS_AUTOMATIC: 448 case IEEE80211_SMPS_NUM_MODES: 449 WARN_ON(1); 450 case IEEE80211_SMPS_OFF: 451 action_frame->u.action.u.ht_smps.smps_control = 452 WLAN_HT_SMPS_CONTROL_DISABLED; 453 break; 454 case IEEE80211_SMPS_STATIC: 455 action_frame->u.action.u.ht_smps.smps_control = 456 WLAN_HT_SMPS_CONTROL_STATIC; 457 break; 458 case IEEE80211_SMPS_DYNAMIC: 459 action_frame->u.action.u.ht_smps.smps_control = 460 WLAN_HT_SMPS_CONTROL_DYNAMIC; 461 break; 462 } 463 464 /* we'll do more on status of this frame */ 465 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS; 466 ieee80211_tx_skb(sdata, skb); 467 468 return 0; 469 } 470 471 void ieee80211_request_smps_mgd_work(struct work_struct *work) 472 { 473 struct ieee80211_sub_if_data *sdata = 474 container_of(work, struct ieee80211_sub_if_data, 475 u.mgd.request_smps_work); 476 477 sdata_lock(sdata); 478 __ieee80211_request_smps_mgd(sdata, sdata->u.mgd.driver_smps_mode); 479 sdata_unlock(sdata); 480 } 481 482 void ieee80211_request_smps_ap_work(struct work_struct *work) 483 { 484 struct ieee80211_sub_if_data *sdata = 485 container_of(work, struct ieee80211_sub_if_data, 486 u.ap.request_smps_work); 487 488 sdata_lock(sdata); 489 if (sdata_dereference(sdata->u.ap.beacon, sdata)) 490 __ieee80211_request_smps_ap(sdata, 491 sdata->u.ap.driver_smps_mode); 492 sdata_unlock(sdata); 493 } 494 495 void ieee80211_request_smps(struct ieee80211_vif *vif, 496 enum ieee80211_smps_mode smps_mode) 497 { 498 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 499 500 if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION && 501 vif->type != NL80211_IFTYPE_AP)) 502 return; 503 504 if (vif->type == NL80211_IFTYPE_STATION) { 505 if (sdata->u.mgd.driver_smps_mode == smps_mode) 506 return; 507 sdata->u.mgd.driver_smps_mode = smps_mode; 508 ieee80211_queue_work(&sdata->local->hw, 509 &sdata->u.mgd.request_smps_work); 510 } else { 511 /* AUTOMATIC is meaningless in AP mode */ 512 if (WARN_ON_ONCE(smps_mode == IEEE80211_SMPS_AUTOMATIC)) 513 return; 514 if (sdata->u.ap.driver_smps_mode == smps_mode) 515 return; 516 sdata->u.ap.driver_smps_mode = smps_mode; 517 ieee80211_queue_work(&sdata->local->hw, 518 &sdata->u.ap.request_smps_work); 519 } 520 } 521 /* this might change ... don't want non-open drivers using it */ 522 EXPORT_SYMBOL_GPL(ieee80211_request_smps); 523