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 * Copyright(c) 2015-2017 Intel Deutschland GmbH 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 as 14 * published by the Free Software Foundation. 15 */ 16 17 /** 18 * DOC: RX A-MPDU aggregation 19 * 20 * Aggregation on the RX side requires only implementing the 21 * @ampdu_action callback that is invoked to start/stop any 22 * block-ack sessions for RX aggregation. 23 * 24 * When RX aggregation is started by the peer, the driver is 25 * notified via @ampdu_action function, with the 26 * %IEEE80211_AMPDU_RX_START action, and may reject the request 27 * in which case a negative response is sent to the peer, if it 28 * accepts it a positive response is sent. 29 * 30 * While the session is active, the device/driver are required 31 * to de-aggregate frames and pass them up one by one to mac80211, 32 * which will handle the reorder buffer. 33 * 34 * When the aggregation session is stopped again by the peer or 35 * ourselves, the driver's @ampdu_action function will be called 36 * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the 37 * call must not fail. 38 */ 39 40 #include <linux/ieee80211.h> 41 #include <linux/slab.h> 42 #include <linux/export.h> 43 #include <net/mac80211.h> 44 #include "ieee80211_i.h" 45 #include "driver-ops.h" 46 47 static void ieee80211_free_tid_rx(struct rcu_head *h) 48 { 49 struct tid_ampdu_rx *tid_rx = 50 container_of(h, struct tid_ampdu_rx, rcu_head); 51 int i; 52 53 for (i = 0; i < tid_rx->buf_size; i++) 54 __skb_queue_purge(&tid_rx->reorder_buf[i]); 55 kfree(tid_rx->reorder_buf); 56 kfree(tid_rx->reorder_time); 57 kfree(tid_rx); 58 } 59 60 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, 61 u16 initiator, u16 reason, bool tx) 62 { 63 struct ieee80211_local *local = sta->local; 64 struct tid_ampdu_rx *tid_rx; 65 struct ieee80211_ampdu_params params = { 66 .sta = &sta->sta, 67 .action = IEEE80211_AMPDU_RX_STOP, 68 .tid = tid, 69 .amsdu = false, 70 .timeout = 0, 71 .ssn = 0, 72 }; 73 74 lockdep_assert_held(&sta->ampdu_mlme.mtx); 75 76 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid], 77 lockdep_is_held(&sta->ampdu_mlme.mtx)); 78 79 if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid)) 80 return; 81 82 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL); 83 __clear_bit(tid, sta->ampdu_mlme.agg_session_valid); 84 85 ht_dbg(sta->sdata, 86 "Rx BA session stop requested for %pM tid %u %s reason: %d\n", 87 sta->sta.addr, tid, 88 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "initiator", 89 (int)reason); 90 91 if (drv_ampdu_action(local, sta->sdata, ¶ms)) 92 sdata_info(sta->sdata, 93 "HW problem - can not stop rx aggregation for %pM tid %d\n", 94 sta->sta.addr, tid); 95 96 /* check if this is a self generated aggregation halt */ 97 if (initiator == WLAN_BACK_RECIPIENT && tx) 98 ieee80211_send_delba(sta->sdata, sta->sta.addr, 99 tid, WLAN_BACK_RECIPIENT, reason); 100 101 /* 102 * return here in case tid_rx is not assigned - which will happen if 103 * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set. 104 */ 105 if (!tid_rx) 106 return; 107 108 del_timer_sync(&tid_rx->session_timer); 109 110 /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */ 111 spin_lock_bh(&tid_rx->reorder_lock); 112 tid_rx->removed = true; 113 spin_unlock_bh(&tid_rx->reorder_lock); 114 del_timer_sync(&tid_rx->reorder_timer); 115 116 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx); 117 } 118 119 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, 120 u16 initiator, u16 reason, bool tx) 121 { 122 mutex_lock(&sta->ampdu_mlme.mtx); 123 ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx); 124 mutex_unlock(&sta->ampdu_mlme.mtx); 125 } 126 127 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap, 128 const u8 *addr) 129 { 130 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 131 struct sta_info *sta; 132 int i; 133 134 rcu_read_lock(); 135 sta = sta_info_get_bss(sdata, addr); 136 if (!sta) { 137 rcu_read_unlock(); 138 return; 139 } 140 141 for (i = 0; i < IEEE80211_NUM_TIDS; i++) 142 if (ba_rx_bitmap & BIT(i)) 143 set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested); 144 145 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); 146 rcu_read_unlock(); 147 } 148 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session); 149 150 /* 151 * After accepting the AddBA Request we activated a timer, 152 * resetting it after each frame that arrives from the originator. 153 */ 154 static void sta_rx_agg_session_timer_expired(struct timer_list *t) 155 { 156 struct tid_ampdu_rx *tid_rx_timer = 157 from_timer(tid_rx_timer, t, session_timer); 158 struct sta_info *sta = tid_rx_timer->sta; 159 u8 tid = tid_rx_timer->tid; 160 struct tid_ampdu_rx *tid_rx; 161 unsigned long timeout; 162 163 rcu_read_lock(); 164 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 165 if (!tid_rx) { 166 rcu_read_unlock(); 167 return; 168 } 169 170 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); 171 if (time_is_after_jiffies(timeout)) { 172 mod_timer(&tid_rx->session_timer, timeout); 173 rcu_read_unlock(); 174 return; 175 } 176 rcu_read_unlock(); 177 178 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n", 179 sta->sta.addr, tid); 180 181 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired); 182 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); 183 } 184 185 static void sta_rx_agg_reorder_timer_expired(struct timer_list *t) 186 { 187 struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer); 188 189 rcu_read_lock(); 190 ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid); 191 rcu_read_unlock(); 192 } 193 194 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid, 195 u8 dialog_token, u16 status, u16 policy, 196 u16 buf_size, u16 timeout) 197 { 198 struct ieee80211_local *local = sdata->local; 199 struct sk_buff *skb; 200 struct ieee80211_mgmt *mgmt; 201 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU); 202 u16 capab; 203 204 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); 205 if (!skb) 206 return; 207 208 skb_reserve(skb, local->hw.extra_tx_headroom); 209 mgmt = skb_put_zero(skb, 24); 210 memcpy(mgmt->da, da, ETH_ALEN); 211 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 212 if (sdata->vif.type == NL80211_IFTYPE_AP || 213 sdata->vif.type == NL80211_IFTYPE_AP_VLAN || 214 sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 215 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 216 else if (sdata->vif.type == NL80211_IFTYPE_STATION) 217 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); 218 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 219 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); 220 221 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 222 IEEE80211_STYPE_ACTION); 223 224 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp)); 225 mgmt->u.action.category = WLAN_CATEGORY_BACK; 226 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP; 227 mgmt->u.action.u.addba_resp.dialog_token = dialog_token; 228 229 capab = (u16)(amsdu << 0); /* bit 0 A-MSDU support */ 230 capab |= (u16)(policy << 1); /* bit 1 aggregation policy */ 231 capab |= (u16)(tid << 2); /* bit 5:2 TID number */ 232 capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */ 233 234 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab); 235 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout); 236 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status); 237 238 ieee80211_tx_skb(sdata, skb); 239 } 240 241 void ___ieee80211_start_rx_ba_session(struct sta_info *sta, 242 u8 dialog_token, u16 timeout, 243 u16 start_seq_num, u16 ba_policy, u16 tid, 244 u16 buf_size, bool tx, bool auto_seq) 245 { 246 struct ieee80211_local *local = sta->sdata->local; 247 struct tid_ampdu_rx *tid_agg_rx; 248 struct ieee80211_ampdu_params params = { 249 .sta = &sta->sta, 250 .action = IEEE80211_AMPDU_RX_START, 251 .tid = tid, 252 .amsdu = false, 253 .timeout = timeout, 254 .ssn = start_seq_num, 255 }; 256 int i, ret = -EOPNOTSUPP; 257 u16 status = WLAN_STATUS_REQUEST_DECLINED; 258 259 if (tid >= IEEE80211_FIRST_TSPEC_TSID) { 260 ht_dbg(sta->sdata, 261 "STA %pM requests BA session on unsupported tid %d\n", 262 sta->sta.addr, tid); 263 goto end; 264 } 265 266 if (!sta->sta.ht_cap.ht_supported) { 267 ht_dbg(sta->sdata, 268 "STA %pM erroneously requests BA session on tid %d w/o QoS\n", 269 sta->sta.addr, tid); 270 /* send a response anyway, it's an error case if we get here */ 271 goto end; 272 } 273 274 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 275 ht_dbg(sta->sdata, 276 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", 277 sta->sta.addr, tid); 278 goto end; 279 } 280 281 /* sanity check for incoming parameters: 282 * check if configuration can support the BA policy 283 * and if buffer size does not exceeds max value */ 284 /* XXX: check own ht delayed BA capability?? */ 285 if (((ba_policy != 1) && 286 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || 287 (buf_size > IEEE80211_MAX_AMPDU_BUF)) { 288 status = WLAN_STATUS_INVALID_QOS_PARAM; 289 ht_dbg_ratelimited(sta->sdata, 290 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", 291 sta->sta.addr, tid, ba_policy, buf_size); 292 goto end; 293 } 294 /* determine default buffer size */ 295 if (buf_size == 0) 296 buf_size = IEEE80211_MAX_AMPDU_BUF; 297 298 /* make sure the size doesn't exceed the maximum supported by the hw */ 299 if (buf_size > sta->sta.max_rx_aggregation_subframes) 300 buf_size = sta->sta.max_rx_aggregation_subframes; 301 params.buf_size = buf_size; 302 303 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n", 304 buf_size, sta->sta.addr); 305 306 /* examine state machine */ 307 lockdep_assert_held(&sta->ampdu_mlme.mtx); 308 309 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) { 310 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) { 311 ht_dbg_ratelimited(sta->sdata, 312 "updated AddBA Req from %pM on tid %u\n", 313 sta->sta.addr, tid); 314 /* We have no API to update the timeout value in the 315 * driver so reject the timeout update. 316 */ 317 status = WLAN_STATUS_REQUEST_DECLINED; 318 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, 319 tid, dialog_token, status, 320 1, buf_size, timeout); 321 goto end; 322 } 323 324 ht_dbg_ratelimited(sta->sdata, 325 "unexpected AddBA Req from %pM on tid %u\n", 326 sta->sta.addr, tid); 327 328 /* delete existing Rx BA session on the same tid */ 329 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 330 WLAN_STATUS_UNSPECIFIED_QOS, 331 false); 332 } 333 334 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) { 335 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 336 ht_dbg(sta->sdata, 337 "Rx A-MPDU request on %pM tid %d result %d\n", 338 sta->sta.addr, tid, ret); 339 if (!ret) 340 status = WLAN_STATUS_SUCCESS; 341 goto end; 342 } 343 344 /* prepare A-MPDU MLME for Rx aggregation */ 345 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL); 346 if (!tid_agg_rx) 347 goto end; 348 349 spin_lock_init(&tid_agg_rx->reorder_lock); 350 351 /* rx timer */ 352 timer_setup(&tid_agg_rx->session_timer, 353 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE); 354 355 /* rx reorder timer */ 356 timer_setup(&tid_agg_rx->reorder_timer, 357 sta_rx_agg_reorder_timer_expired, 0); 358 359 /* prepare reordering buffer */ 360 tid_agg_rx->reorder_buf = 361 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); 362 tid_agg_rx->reorder_time = 363 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); 364 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { 365 kfree(tid_agg_rx->reorder_buf); 366 kfree(tid_agg_rx->reorder_time); 367 kfree(tid_agg_rx); 368 goto end; 369 } 370 371 for (i = 0; i < buf_size; i++) 372 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); 373 374 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 375 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", 376 sta->sta.addr, tid, ret); 377 if (ret) { 378 kfree(tid_agg_rx->reorder_buf); 379 kfree(tid_agg_rx->reorder_time); 380 kfree(tid_agg_rx); 381 goto end; 382 } 383 384 /* update data */ 385 tid_agg_rx->ssn = start_seq_num; 386 tid_agg_rx->head_seq_num = start_seq_num; 387 tid_agg_rx->buf_size = buf_size; 388 tid_agg_rx->timeout = timeout; 389 tid_agg_rx->stored_mpdu_num = 0; 390 tid_agg_rx->auto_seq = auto_seq; 391 tid_agg_rx->started = false; 392 tid_agg_rx->reorder_buf_filtered = 0; 393 tid_agg_rx->tid = tid; 394 tid_agg_rx->sta = sta; 395 status = WLAN_STATUS_SUCCESS; 396 397 /* activate it for RX */ 398 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); 399 400 if (timeout) { 401 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); 402 tid_agg_rx->last_rx = jiffies; 403 } 404 405 end: 406 if (status == WLAN_STATUS_SUCCESS) { 407 __set_bit(tid, sta->ampdu_mlme.agg_session_valid); 408 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg); 409 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token; 410 } 411 412 if (tx) 413 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid, 414 dialog_token, status, 1, buf_size, 415 timeout); 416 } 417 418 void __ieee80211_start_rx_ba_session(struct sta_info *sta, 419 u8 dialog_token, u16 timeout, 420 u16 start_seq_num, u16 ba_policy, u16 tid, 421 u16 buf_size, bool tx, bool auto_seq) 422 { 423 mutex_lock(&sta->ampdu_mlme.mtx); 424 ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 425 start_seq_num, ba_policy, tid, 426 buf_size, tx, auto_seq); 427 mutex_unlock(&sta->ampdu_mlme.mtx); 428 } 429 430 void ieee80211_process_addba_request(struct ieee80211_local *local, 431 struct sta_info *sta, 432 struct ieee80211_mgmt *mgmt, 433 size_t len) 434 { 435 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; 436 u8 dialog_token; 437 438 /* extract session parameters from addba request frame */ 439 dialog_token = mgmt->u.action.u.addba_req.dialog_token; 440 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); 441 start_seq_num = 442 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; 443 444 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); 445 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; 446 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; 447 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; 448 449 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 450 start_seq_num, ba_policy, tid, 451 buf_size, true, false); 452 } 453 454 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif, 455 const u8 *addr, unsigned int tid) 456 { 457 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 458 struct ieee80211_local *local = sdata->local; 459 struct sta_info *sta; 460 461 rcu_read_lock(); 462 sta = sta_info_get_bss(sdata, addr); 463 if (!sta) 464 goto unlock; 465 466 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl); 467 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 468 unlock: 469 rcu_read_unlock(); 470 } 471 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl); 472 473 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif, 474 const u8 *addr, unsigned int tid) 475 { 476 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 477 struct ieee80211_local *local = sdata->local; 478 struct sta_info *sta; 479 480 rcu_read_lock(); 481 sta = sta_info_get_bss(sdata, addr); 482 if (!sta) 483 goto unlock; 484 485 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired); 486 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 487 488 unlock: 489 rcu_read_unlock(); 490 } 491 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired); 492