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 * Copyright (C) 2018 Intel Corporation 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License version 2 as 15 * published by the Free Software Foundation. 16 */ 17 18 /** 19 * DOC: RX A-MPDU aggregation 20 * 21 * Aggregation on the RX side requires only implementing the 22 * @ampdu_action callback that is invoked to start/stop any 23 * block-ack sessions for RX aggregation. 24 * 25 * When RX aggregation is started by the peer, the driver is 26 * notified via @ampdu_action function, with the 27 * %IEEE80211_AMPDU_RX_START action, and may reject the request 28 * in which case a negative response is sent to the peer, if it 29 * accepts it a positive response is sent. 30 * 31 * While the session is active, the device/driver are required 32 * to de-aggregate frames and pass them up one by one to mac80211, 33 * which will handle the reorder buffer. 34 * 35 * When the aggregation session is stopped again by the peer or 36 * ourselves, the driver's @ampdu_action function will be called 37 * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the 38 * call must not fail. 39 */ 40 41 #include <linux/ieee80211.h> 42 #include <linux/slab.h> 43 #include <linux/export.h> 44 #include <net/mac80211.h> 45 #include "ieee80211_i.h" 46 #include "driver-ops.h" 47 48 static void ieee80211_free_tid_rx(struct rcu_head *h) 49 { 50 struct tid_ampdu_rx *tid_rx = 51 container_of(h, struct tid_ampdu_rx, rcu_head); 52 int i; 53 54 for (i = 0; i < tid_rx->buf_size; i++) 55 __skb_queue_purge(&tid_rx->reorder_buf[i]); 56 kfree(tid_rx->reorder_buf); 57 kfree(tid_rx->reorder_time); 58 kfree(tid_rx); 59 } 60 61 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, 62 u16 initiator, u16 reason, bool tx) 63 { 64 struct ieee80211_local *local = sta->local; 65 struct tid_ampdu_rx *tid_rx; 66 struct ieee80211_ampdu_params params = { 67 .sta = &sta->sta, 68 .action = IEEE80211_AMPDU_RX_STOP, 69 .tid = tid, 70 .amsdu = false, 71 .timeout = 0, 72 .ssn = 0, 73 }; 74 75 lockdep_assert_held(&sta->ampdu_mlme.mtx); 76 77 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid], 78 lockdep_is_held(&sta->ampdu_mlme.mtx)); 79 80 if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid)) 81 return; 82 83 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL); 84 __clear_bit(tid, sta->ampdu_mlme.agg_session_valid); 85 86 ht_dbg(sta->sdata, 87 "Rx BA session stop requested for %pM tid %u %s reason: %d\n", 88 sta->sta.addr, tid, 89 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "initiator", 90 (int)reason); 91 92 if (drv_ampdu_action(local, sta->sdata, ¶ms)) 93 sdata_info(sta->sdata, 94 "HW problem - can not stop rx aggregation for %pM tid %d\n", 95 sta->sta.addr, tid); 96 97 /* check if this is a self generated aggregation halt */ 98 if (initiator == WLAN_BACK_RECIPIENT && tx) 99 ieee80211_send_delba(sta->sdata, sta->sta.addr, 100 tid, WLAN_BACK_RECIPIENT, reason); 101 102 /* 103 * return here in case tid_rx is not assigned - which will happen if 104 * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set. 105 */ 106 if (!tid_rx) 107 return; 108 109 del_timer_sync(&tid_rx->session_timer); 110 111 /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */ 112 spin_lock_bh(&tid_rx->reorder_lock); 113 tid_rx->removed = true; 114 spin_unlock_bh(&tid_rx->reorder_lock); 115 del_timer_sync(&tid_rx->reorder_timer); 116 117 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx); 118 } 119 120 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, 121 u16 initiator, u16 reason, bool tx) 122 { 123 mutex_lock(&sta->ampdu_mlme.mtx); 124 ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx); 125 mutex_unlock(&sta->ampdu_mlme.mtx); 126 } 127 128 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap, 129 const u8 *addr) 130 { 131 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 132 struct sta_info *sta; 133 int i; 134 135 rcu_read_lock(); 136 sta = sta_info_get_bss(sdata, addr); 137 if (!sta) { 138 rcu_read_unlock(); 139 return; 140 } 141 142 for (i = 0; i < IEEE80211_NUM_TIDS; i++) 143 if (ba_rx_bitmap & BIT(i)) 144 set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested); 145 146 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); 147 rcu_read_unlock(); 148 } 149 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session); 150 151 /* 152 * After accepting the AddBA Request we activated a timer, 153 * resetting it after each frame that arrives from the originator. 154 */ 155 static void sta_rx_agg_session_timer_expired(struct timer_list *t) 156 { 157 struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, session_timer); 158 struct sta_info *sta = tid_rx->sta; 159 u8 tid = tid_rx->tid; 160 unsigned long timeout; 161 162 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); 163 if (time_is_after_jiffies(timeout)) { 164 mod_timer(&tid_rx->session_timer, timeout); 165 return; 166 } 167 168 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n", 169 sta->sta.addr, tid); 170 171 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired); 172 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); 173 } 174 175 static void sta_rx_agg_reorder_timer_expired(struct timer_list *t) 176 { 177 struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer); 178 179 rcu_read_lock(); 180 ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid); 181 rcu_read_unlock(); 182 } 183 184 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid, 185 u8 dialog_token, u16 status, u16 policy, 186 u16 buf_size, u16 timeout) 187 { 188 struct ieee80211_local *local = sdata->local; 189 struct sk_buff *skb; 190 struct ieee80211_mgmt *mgmt; 191 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU); 192 u16 capab; 193 194 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); 195 if (!skb) 196 return; 197 198 skb_reserve(skb, local->hw.extra_tx_headroom); 199 mgmt = skb_put_zero(skb, 24); 200 memcpy(mgmt->da, da, ETH_ALEN); 201 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 202 if (sdata->vif.type == NL80211_IFTYPE_AP || 203 sdata->vif.type == NL80211_IFTYPE_AP_VLAN || 204 sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 205 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 206 else if (sdata->vif.type == NL80211_IFTYPE_STATION) 207 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); 208 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 209 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); 210 211 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 212 IEEE80211_STYPE_ACTION); 213 214 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp)); 215 mgmt->u.action.category = WLAN_CATEGORY_BACK; 216 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP; 217 mgmt->u.action.u.addba_resp.dialog_token = dialog_token; 218 219 capab = (u16)(amsdu << 0); /* bit 0 A-MSDU support */ 220 capab |= (u16)(policy << 1); /* bit 1 aggregation policy */ 221 capab |= (u16)(tid << 2); /* bit 5:2 TID number */ 222 capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */ 223 224 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab); 225 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout); 226 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status); 227 228 ieee80211_tx_skb(sdata, skb); 229 } 230 231 void ___ieee80211_start_rx_ba_session(struct sta_info *sta, 232 u8 dialog_token, u16 timeout, 233 u16 start_seq_num, u16 ba_policy, u16 tid, 234 u16 buf_size, bool tx, bool auto_seq) 235 { 236 struct ieee80211_local *local = sta->sdata->local; 237 struct tid_ampdu_rx *tid_agg_rx; 238 struct ieee80211_ampdu_params params = { 239 .sta = &sta->sta, 240 .action = IEEE80211_AMPDU_RX_START, 241 .tid = tid, 242 .amsdu = false, 243 .timeout = timeout, 244 .ssn = start_seq_num, 245 }; 246 int i, ret = -EOPNOTSUPP; 247 u16 status = WLAN_STATUS_REQUEST_DECLINED; 248 249 if (tid >= IEEE80211_FIRST_TSPEC_TSID) { 250 ht_dbg(sta->sdata, 251 "STA %pM requests BA session on unsupported tid %d\n", 252 sta->sta.addr, tid); 253 goto end; 254 } 255 256 if (!sta->sta.ht_cap.ht_supported) { 257 ht_dbg(sta->sdata, 258 "STA %pM erroneously requests BA session on tid %d w/o QoS\n", 259 sta->sta.addr, tid); 260 /* send a response anyway, it's an error case if we get here */ 261 goto end; 262 } 263 264 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 265 ht_dbg(sta->sdata, 266 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", 267 sta->sta.addr, tid); 268 goto end; 269 } 270 271 /* sanity check for incoming parameters: 272 * check if configuration can support the BA policy 273 * and if buffer size does not exceeds max value */ 274 /* XXX: check own ht delayed BA capability?? */ 275 if (((ba_policy != 1) && 276 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || 277 (buf_size > IEEE80211_MAX_AMPDU_BUF)) { 278 status = WLAN_STATUS_INVALID_QOS_PARAM; 279 ht_dbg_ratelimited(sta->sdata, 280 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", 281 sta->sta.addr, tid, ba_policy, buf_size); 282 goto end; 283 } 284 /* determine default buffer size */ 285 if (buf_size == 0) 286 buf_size = IEEE80211_MAX_AMPDU_BUF; 287 288 /* make sure the size doesn't exceed the maximum supported by the hw */ 289 if (buf_size > sta->sta.max_rx_aggregation_subframes) 290 buf_size = sta->sta.max_rx_aggregation_subframes; 291 params.buf_size = buf_size; 292 293 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n", 294 buf_size, sta->sta.addr); 295 296 /* examine state machine */ 297 lockdep_assert_held(&sta->ampdu_mlme.mtx); 298 299 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) { 300 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) { 301 struct tid_ampdu_rx *tid_rx; 302 303 ht_dbg_ratelimited(sta->sdata, 304 "updated AddBA Req from %pM on tid %u\n", 305 sta->sta.addr, tid); 306 /* We have no API to update the timeout value in the 307 * driver so reject the timeout update if the timeout 308 * changed. If if did not change, i.e., no real update, 309 * just reply with success. 310 */ 311 rcu_read_lock(); 312 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); 313 if (tid_rx && tid_rx->timeout == timeout) 314 status = WLAN_STATUS_SUCCESS; 315 else 316 status = WLAN_STATUS_REQUEST_DECLINED; 317 rcu_read_unlock(); 318 goto end; 319 } 320 321 ht_dbg_ratelimited(sta->sdata, 322 "unexpected AddBA Req from %pM on tid %u\n", 323 sta->sta.addr, tid); 324 325 /* delete existing Rx BA session on the same tid */ 326 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 327 WLAN_STATUS_UNSPECIFIED_QOS, 328 false); 329 } 330 331 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) { 332 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 333 ht_dbg(sta->sdata, 334 "Rx A-MPDU request on %pM tid %d result %d\n", 335 sta->sta.addr, tid, ret); 336 if (!ret) 337 status = WLAN_STATUS_SUCCESS; 338 goto end; 339 } 340 341 /* prepare A-MPDU MLME for Rx aggregation */ 342 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL); 343 if (!tid_agg_rx) 344 goto end; 345 346 spin_lock_init(&tid_agg_rx->reorder_lock); 347 348 /* rx timer */ 349 timer_setup(&tid_agg_rx->session_timer, 350 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE); 351 352 /* rx reorder timer */ 353 timer_setup(&tid_agg_rx->reorder_timer, 354 sta_rx_agg_reorder_timer_expired, 0); 355 356 /* prepare reordering buffer */ 357 tid_agg_rx->reorder_buf = 358 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); 359 tid_agg_rx->reorder_time = 360 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); 361 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { 362 kfree(tid_agg_rx->reorder_buf); 363 kfree(tid_agg_rx->reorder_time); 364 kfree(tid_agg_rx); 365 goto end; 366 } 367 368 for (i = 0; i < buf_size; i++) 369 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); 370 371 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 372 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", 373 sta->sta.addr, tid, ret); 374 if (ret) { 375 kfree(tid_agg_rx->reorder_buf); 376 kfree(tid_agg_rx->reorder_time); 377 kfree(tid_agg_rx); 378 goto end; 379 } 380 381 /* update data */ 382 tid_agg_rx->ssn = start_seq_num; 383 tid_agg_rx->head_seq_num = start_seq_num; 384 tid_agg_rx->buf_size = buf_size; 385 tid_agg_rx->timeout = timeout; 386 tid_agg_rx->stored_mpdu_num = 0; 387 tid_agg_rx->auto_seq = auto_seq; 388 tid_agg_rx->started = false; 389 tid_agg_rx->reorder_buf_filtered = 0; 390 tid_agg_rx->tid = tid; 391 tid_agg_rx->sta = sta; 392 status = WLAN_STATUS_SUCCESS; 393 394 /* activate it for RX */ 395 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); 396 397 if (timeout) { 398 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); 399 tid_agg_rx->last_rx = jiffies; 400 } 401 402 end: 403 if (status == WLAN_STATUS_SUCCESS) { 404 __set_bit(tid, sta->ampdu_mlme.agg_session_valid); 405 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg); 406 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token; 407 } 408 409 if (tx) 410 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid, 411 dialog_token, status, 1, buf_size, 412 timeout); 413 } 414 415 static void __ieee80211_start_rx_ba_session(struct sta_info *sta, 416 u8 dialog_token, u16 timeout, 417 u16 start_seq_num, u16 ba_policy, 418 u16 tid, u16 buf_size, bool tx, 419 bool auto_seq) 420 { 421 mutex_lock(&sta->ampdu_mlme.mtx); 422 ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 423 start_seq_num, ba_policy, tid, 424 buf_size, tx, auto_seq); 425 mutex_unlock(&sta->ampdu_mlme.mtx); 426 } 427 428 void ieee80211_process_addba_request(struct ieee80211_local *local, 429 struct sta_info *sta, 430 struct ieee80211_mgmt *mgmt, 431 size_t len) 432 { 433 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; 434 u8 dialog_token; 435 436 /* extract session parameters from addba request frame */ 437 dialog_token = mgmt->u.action.u.addba_req.dialog_token; 438 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); 439 start_seq_num = 440 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; 441 442 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); 443 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; 444 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; 445 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; 446 447 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 448 start_seq_num, ba_policy, tid, 449 buf_size, true, false); 450 } 451 452 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif, 453 const u8 *addr, unsigned int tid) 454 { 455 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 456 struct ieee80211_local *local = sdata->local; 457 struct sta_info *sta; 458 459 rcu_read_lock(); 460 sta = sta_info_get_bss(sdata, addr); 461 if (!sta) 462 goto unlock; 463 464 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl); 465 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 466 unlock: 467 rcu_read_unlock(); 468 } 469 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl); 470 471 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif, 472 const u8 *addr, unsigned int tid) 473 { 474 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 475 struct ieee80211_local *local = sdata->local; 476 struct sta_info *sta; 477 478 rcu_read_lock(); 479 sta = sta_info_get_bss(sdata, addr); 480 if (!sta) 481 goto unlock; 482 483 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired); 484 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 485 486 unlock: 487 rcu_read_unlock(); 488 } 489 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired); 490