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 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" : "inititator", 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(unsigned long data) 155 { 156 /* not an elegant detour, but there is no choice as the timer passes 157 * only one argument, and various sta_info are needed here, so init 158 * flow in sta_info_create gives the TID as data, while the timer_to_id 159 * array gives the sta through container_of */ 160 u8 *ptid = (u8 *)data; 161 u8 *timer_to_id = ptid - *ptid; 162 struct sta_info *sta = container_of(timer_to_id, struct sta_info, 163 timer_to_tid[0]); 164 struct tid_ampdu_rx *tid_rx; 165 unsigned long timeout; 166 167 rcu_read_lock(); 168 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]); 169 if (!tid_rx) { 170 rcu_read_unlock(); 171 return; 172 } 173 174 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); 175 if (time_is_after_jiffies(timeout)) { 176 mod_timer(&tid_rx->session_timer, timeout); 177 rcu_read_unlock(); 178 return; 179 } 180 rcu_read_unlock(); 181 182 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n", 183 sta->sta.addr, (u16)*ptid); 184 185 set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired); 186 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); 187 } 188 189 static void sta_rx_agg_reorder_timer_expired(unsigned long data) 190 { 191 u8 *ptid = (u8 *)data; 192 u8 *timer_to_id = ptid - *ptid; 193 struct sta_info *sta = container_of(timer_to_id, struct sta_info, 194 timer_to_tid[0]); 195 196 rcu_read_lock(); 197 ieee80211_release_reorder_timeout(sta, *ptid); 198 rcu_read_unlock(); 199 } 200 201 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid, 202 u8 dialog_token, u16 status, u16 policy, 203 u16 buf_size, u16 timeout) 204 { 205 struct ieee80211_local *local = sdata->local; 206 struct sk_buff *skb; 207 struct ieee80211_mgmt *mgmt; 208 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU); 209 u16 capab; 210 211 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); 212 if (!skb) 213 return; 214 215 skb_reserve(skb, local->hw.extra_tx_headroom); 216 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24); 217 memset(mgmt, 0, 24); 218 memcpy(mgmt->da, da, ETH_ALEN); 219 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 220 if (sdata->vif.type == NL80211_IFTYPE_AP || 221 sdata->vif.type == NL80211_IFTYPE_AP_VLAN || 222 sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 223 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 224 else if (sdata->vif.type == NL80211_IFTYPE_STATION) 225 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); 226 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 227 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); 228 229 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 230 IEEE80211_STYPE_ACTION); 231 232 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp)); 233 mgmt->u.action.category = WLAN_CATEGORY_BACK; 234 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP; 235 mgmt->u.action.u.addba_resp.dialog_token = dialog_token; 236 237 capab = (u16)(amsdu << 0); /* bit 0 A-MSDU support */ 238 capab |= (u16)(policy << 1); /* bit 1 aggregation policy */ 239 capab |= (u16)(tid << 2); /* bit 5:2 TID number */ 240 capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */ 241 242 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab); 243 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout); 244 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status); 245 246 ieee80211_tx_skb(sdata, skb); 247 } 248 249 void __ieee80211_start_rx_ba_session(struct sta_info *sta, 250 u8 dialog_token, u16 timeout, 251 u16 start_seq_num, u16 ba_policy, u16 tid, 252 u16 buf_size, bool tx, bool auto_seq) 253 { 254 struct ieee80211_local *local = sta->sdata->local; 255 struct tid_ampdu_rx *tid_agg_rx; 256 struct ieee80211_ampdu_params params = { 257 .sta = &sta->sta, 258 .action = IEEE80211_AMPDU_RX_START, 259 .tid = tid, 260 .amsdu = false, 261 .timeout = timeout, 262 .ssn = start_seq_num, 263 }; 264 int i, ret = -EOPNOTSUPP; 265 u16 status = WLAN_STATUS_REQUEST_DECLINED; 266 267 if (tid >= IEEE80211_FIRST_TSPEC_TSID) { 268 ht_dbg(sta->sdata, 269 "STA %pM requests BA session on unsupported tid %d\n", 270 sta->sta.addr, tid); 271 goto end_no_lock; 272 } 273 274 if (!sta->sta.ht_cap.ht_supported) { 275 ht_dbg(sta->sdata, 276 "STA %pM erroneously requests BA session on tid %d w/o QoS\n", 277 sta->sta.addr, tid); 278 /* send a response anyway, it's an error case if we get here */ 279 goto end_no_lock; 280 } 281 282 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 283 ht_dbg(sta->sdata, 284 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", 285 sta->sta.addr, tid); 286 goto end_no_lock; 287 } 288 289 /* sanity check for incoming parameters: 290 * check if configuration can support the BA policy 291 * and if buffer size does not exceeds max value */ 292 /* XXX: check own ht delayed BA capability?? */ 293 if (((ba_policy != 1) && 294 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || 295 (buf_size > IEEE80211_MAX_AMPDU_BUF)) { 296 status = WLAN_STATUS_INVALID_QOS_PARAM; 297 ht_dbg_ratelimited(sta->sdata, 298 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", 299 sta->sta.addr, tid, ba_policy, buf_size); 300 goto end_no_lock; 301 } 302 /* determine default buffer size */ 303 if (buf_size == 0) 304 buf_size = IEEE80211_MAX_AMPDU_BUF; 305 306 /* make sure the size doesn't exceed the maximum supported by the hw */ 307 if (buf_size > sta->sta.max_rx_aggregation_subframes) 308 buf_size = sta->sta.max_rx_aggregation_subframes; 309 params.buf_size = buf_size; 310 311 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n", 312 buf_size, sta->sta.addr); 313 314 /* examine state machine */ 315 mutex_lock(&sta->ampdu_mlme.mtx); 316 317 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) { 318 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) { 319 ht_dbg_ratelimited(sta->sdata, 320 "updated AddBA Req from %pM on tid %u\n", 321 sta->sta.addr, tid); 322 /* We have no API to update the timeout value in the 323 * driver so reject the timeout update. 324 */ 325 status = WLAN_STATUS_REQUEST_DECLINED; 326 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, 327 tid, dialog_token, status, 328 1, buf_size, timeout); 329 goto end; 330 } 331 332 ht_dbg_ratelimited(sta->sdata, 333 "unexpected AddBA Req from %pM on tid %u\n", 334 sta->sta.addr, tid); 335 336 /* delete existing Rx BA session on the same tid */ 337 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 338 WLAN_STATUS_UNSPECIFIED_QOS, 339 false); 340 } 341 342 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) { 343 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 344 ht_dbg(sta->sdata, 345 "Rx A-MPDU request on %pM tid %d result %d\n", 346 sta->sta.addr, tid, ret); 347 if (!ret) 348 status = WLAN_STATUS_SUCCESS; 349 goto end; 350 } 351 352 /* prepare A-MPDU MLME for Rx aggregation */ 353 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL); 354 if (!tid_agg_rx) 355 goto end; 356 357 spin_lock_init(&tid_agg_rx->reorder_lock); 358 359 /* rx timer */ 360 tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired; 361 tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid]; 362 init_timer_deferrable(&tid_agg_rx->session_timer); 363 364 /* rx reorder timer */ 365 tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired; 366 tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid]; 367 init_timer(&tid_agg_rx->reorder_timer); 368 369 /* prepare reordering buffer */ 370 tid_agg_rx->reorder_buf = 371 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); 372 tid_agg_rx->reorder_time = 373 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); 374 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { 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 for (i = 0; i < buf_size; i++) 382 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); 383 384 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 385 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", 386 sta->sta.addr, tid, ret); 387 if (ret) { 388 kfree(tid_agg_rx->reorder_buf); 389 kfree(tid_agg_rx->reorder_time); 390 kfree(tid_agg_rx); 391 goto end; 392 } 393 394 /* update data */ 395 tid_agg_rx->ssn = start_seq_num; 396 tid_agg_rx->head_seq_num = start_seq_num; 397 tid_agg_rx->buf_size = buf_size; 398 tid_agg_rx->timeout = timeout; 399 tid_agg_rx->stored_mpdu_num = 0; 400 tid_agg_rx->auto_seq = auto_seq; 401 tid_agg_rx->reorder_buf_filtered = 0; 402 status = WLAN_STATUS_SUCCESS; 403 404 /* activate it for RX */ 405 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); 406 407 if (timeout) { 408 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); 409 tid_agg_rx->last_rx = jiffies; 410 } 411 412 end: 413 if (status == WLAN_STATUS_SUCCESS) { 414 __set_bit(tid, sta->ampdu_mlme.agg_session_valid); 415 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg); 416 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token; 417 } 418 mutex_unlock(&sta->ampdu_mlme.mtx); 419 420 end_no_lock: 421 if (tx) 422 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid, 423 dialog_token, status, 1, buf_size, 424 timeout); 425 } 426 427 void ieee80211_process_addba_request(struct ieee80211_local *local, 428 struct sta_info *sta, 429 struct ieee80211_mgmt *mgmt, 430 size_t len) 431 { 432 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; 433 u8 dialog_token; 434 435 /* extract session parameters from addba request frame */ 436 dialog_token = mgmt->u.action.u.addba_req.dialog_token; 437 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); 438 start_seq_num = 439 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; 440 441 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); 442 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; 443 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; 444 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; 445 446 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, 447 start_seq_num, ba_policy, tid, 448 buf_size, true, false); 449 } 450 451 void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif, 452 const u8 *addr, u16 tid) 453 { 454 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 455 struct ieee80211_local *local = sdata->local; 456 struct ieee80211_rx_agg *rx_agg; 457 struct sk_buff *skb = dev_alloc_skb(0); 458 459 if (unlikely(!skb)) 460 return; 461 462 rx_agg = (struct ieee80211_rx_agg *) &skb->cb; 463 memcpy(&rx_agg->addr, addr, ETH_ALEN); 464 rx_agg->tid = tid; 465 466 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START; 467 skb_queue_tail(&sdata->skb_queue, skb); 468 ieee80211_queue_work(&local->hw, &sdata->work); 469 } 470 EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl); 471 472 void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif, 473 const u8 *addr, u16 tid) 474 { 475 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 476 struct ieee80211_local *local = sdata->local; 477 struct ieee80211_rx_agg *rx_agg; 478 struct sk_buff *skb = dev_alloc_skb(0); 479 480 if (unlikely(!skb)) 481 return; 482 483 rx_agg = (struct ieee80211_rx_agg *) &skb->cb; 484 memcpy(&rx_agg->addr, addr, ETH_ALEN); 485 rx_agg->tid = tid; 486 487 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP; 488 skb_queue_tail(&sdata->skb_queue, skb); 489 ieee80211_queue_work(&local->hw, &sdata->work); 490 } 491 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl); 492