| 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 | /** |
| 17 | * DOC: RX A-MPDU aggregation |
| 18 | * |
| 19 | * Aggregation on the RX side requires only implementing the |
| 20 | * @ampdu_action callback that is invoked to start/stop any |
| 21 | * block-ack sessions for RX aggregation. |
| 22 | * |
| 23 | * When RX aggregation is started by the peer, the driver is |
| 24 | * notified via @ampdu_action function, with the |
| 25 | * %IEEE80211_AMPDU_RX_START action, and may reject the request |
| 26 | * in which case a negative response is sent to the peer, if it |
| 27 | * accepts it a positive response is sent. |
| 28 | * |
| 29 | * While the session is active, the device/driver are required |
| 30 | * to de-aggregate frames and pass them up one by one to mac80211, |
| 31 | * which will handle the reorder buffer. |
| 32 | * |
| 33 | * When the aggregation session is stopped again by the peer or |
| 34 | * ourselves, the driver's @ampdu_action function will be called |
| 35 | * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the |
| 36 | * call must not fail. |
| 37 | */ |
| 38 | |
| 39 | #include <linux/ieee80211.h> |
| 40 | #include <linux/slab.h> |
| 41 | #include <linux/export.h> |
| 42 | #include <net/mac80211.h> |
| 43 | #include "ieee80211_i.h" |
| 44 | #include "driver-ops.h" |
| 45 | |
| 46 | static void ieee80211_free_tid_rx(struct rcu_head *h) |
| 47 | { |
| 48 | struct tid_ampdu_rx *tid_rx = |
| 49 | container_of(h, struct tid_ampdu_rx, rcu_head); |
| 50 | int i; |
| 51 | |
| 52 | del_timer_sync(&tid_rx->reorder_timer); |
| 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 | |
| 67 | lockdep_assert_held(&sta->ampdu_mlme.mtx); |
| 68 | |
| 69 | tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid], |
| 70 | lockdep_is_held(&sta->ampdu_mlme.mtx)); |
| 71 | |
| 72 | if (!tid_rx) |
| 73 | return; |
| 74 | |
| 75 | RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL); |
| 76 | |
| 77 | ht_dbg(sta->sdata, |
| 78 | "Rx BA session stop requested for %pM tid %u %s reason: %d\n", |
| 79 | sta->sta.addr, tid, |
| 80 | initiator == WLAN_BACK_RECIPIENT ? "recipient" : "inititator", |
| 81 | (int)reason); |
| 82 | |
| 83 | if (drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_STOP, |
| 84 | &sta->sta, tid, NULL, 0)) |
| 85 | sdata_info(sta->sdata, |
| 86 | "HW problem - can not stop rx aggregation for %pM tid %d\n", |
| 87 | sta->sta.addr, tid); |
| 88 | |
| 89 | /* check if this is a self generated aggregation halt */ |
| 90 | if (initiator == WLAN_BACK_RECIPIENT && tx) |
| 91 | ieee80211_send_delba(sta->sdata, sta->sta.addr, |
| 92 | tid, WLAN_BACK_RECIPIENT, reason); |
| 93 | |
| 94 | del_timer_sync(&tid_rx->session_timer); |
| 95 | |
| 96 | call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx); |
| 97 | } |
| 98 | |
| 99 | void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, |
| 100 | u16 initiator, u16 reason, bool tx) |
| 101 | { |
| 102 | mutex_lock(&sta->ampdu_mlme.mtx); |
| 103 | ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx); |
| 104 | mutex_unlock(&sta->ampdu_mlme.mtx); |
| 105 | } |
| 106 | |
| 107 | void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap, |
| 108 | const u8 *addr) |
| 109 | { |
| 110 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
| 111 | struct sta_info *sta; |
| 112 | int i; |
| 113 | |
| 114 | rcu_read_lock(); |
| 115 | sta = sta_info_get_bss(sdata, addr); |
| 116 | if (!sta) { |
| 117 | rcu_read_unlock(); |
| 118 | return; |
| 119 | } |
| 120 | |
| 121 | for (i = 0; i < IEEE80211_NUM_TIDS; i++) |
| 122 | if (ba_rx_bitmap & BIT(i)) |
| 123 | set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested); |
| 124 | |
| 125 | ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); |
| 126 | rcu_read_unlock(); |
| 127 | } |
| 128 | EXPORT_SYMBOL(ieee80211_stop_rx_ba_session); |
| 129 | |
| 130 | /* |
| 131 | * After accepting the AddBA Request we activated a timer, |
| 132 | * resetting it after each frame that arrives from the originator. |
| 133 | */ |
| 134 | static void sta_rx_agg_session_timer_expired(unsigned long data) |
| 135 | { |
| 136 | /* not an elegant detour, but there is no choice as the timer passes |
| 137 | * only one argument, and various sta_info are needed here, so init |
| 138 | * flow in sta_info_create gives the TID as data, while the timer_to_id |
| 139 | * array gives the sta through container_of */ |
| 140 | u8 *ptid = (u8 *)data; |
| 141 | u8 *timer_to_id = ptid - *ptid; |
| 142 | struct sta_info *sta = container_of(timer_to_id, struct sta_info, |
| 143 | timer_to_tid[0]); |
| 144 | struct tid_ampdu_rx *tid_rx; |
| 145 | unsigned long timeout; |
| 146 | |
| 147 | rcu_read_lock(); |
| 148 | tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]); |
| 149 | if (!tid_rx) { |
| 150 | rcu_read_unlock(); |
| 151 | return; |
| 152 | } |
| 153 | |
| 154 | timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); |
| 155 | if (time_is_after_jiffies(timeout)) { |
| 156 | mod_timer(&tid_rx->session_timer, timeout); |
| 157 | rcu_read_unlock(); |
| 158 | return; |
| 159 | } |
| 160 | rcu_read_unlock(); |
| 161 | |
| 162 | ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n", |
| 163 | sta->sta.addr, (u16)*ptid); |
| 164 | |
| 165 | set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired); |
| 166 | ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); |
| 167 | } |
| 168 | |
| 169 | static void sta_rx_agg_reorder_timer_expired(unsigned long data) |
| 170 | { |
| 171 | u8 *ptid = (u8 *)data; |
| 172 | u8 *timer_to_id = ptid - *ptid; |
| 173 | struct sta_info *sta = container_of(timer_to_id, struct sta_info, |
| 174 | timer_to_tid[0]); |
| 175 | |
| 176 | rcu_read_lock(); |
| 177 | ieee80211_release_reorder_timeout(sta, *ptid); |
| 178 | rcu_read_unlock(); |
| 179 | } |
| 180 | |
| 181 | static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid, |
| 182 | u8 dialog_token, u16 status, u16 policy, |
| 183 | u16 buf_size, u16 timeout) |
| 184 | { |
| 185 | struct ieee80211_local *local = sdata->local; |
| 186 | struct sk_buff *skb; |
| 187 | struct ieee80211_mgmt *mgmt; |
| 188 | u16 capab; |
| 189 | |
| 190 | skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); |
| 191 | if (!skb) |
| 192 | return; |
| 193 | |
| 194 | skb_reserve(skb, local->hw.extra_tx_headroom); |
| 195 | mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24); |
| 196 | memset(mgmt, 0, 24); |
| 197 | memcpy(mgmt->da, da, ETH_ALEN); |
| 198 | memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); |
| 199 | if (sdata->vif.type == NL80211_IFTYPE_AP || |
| 200 | sdata->vif.type == NL80211_IFTYPE_AP_VLAN || |
| 201 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) |
| 202 | memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); |
| 203 | else if (sdata->vif.type == NL80211_IFTYPE_STATION) |
| 204 | memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); |
| 205 | else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) |
| 206 | memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); |
| 207 | |
| 208 | mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | |
| 209 | IEEE80211_STYPE_ACTION); |
| 210 | |
| 211 | skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp)); |
| 212 | mgmt->u.action.category = WLAN_CATEGORY_BACK; |
| 213 | mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP; |
| 214 | mgmt->u.action.u.addba_resp.dialog_token = dialog_token; |
| 215 | |
| 216 | capab = (u16)(policy << 1); /* bit 1 aggregation policy */ |
| 217 | capab |= (u16)(tid << 2); /* bit 5:2 TID number */ |
| 218 | capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */ |
| 219 | |
| 220 | mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab); |
| 221 | mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout); |
| 222 | mgmt->u.action.u.addba_resp.status = cpu_to_le16(status); |
| 223 | |
| 224 | ieee80211_tx_skb(sdata, skb); |
| 225 | } |
| 226 | |
| 227 | void __ieee80211_start_rx_ba_session(struct sta_info *sta, |
| 228 | u8 dialog_token, u16 timeout, |
| 229 | u16 start_seq_num, u16 ba_policy, u16 tid, |
| 230 | u16 buf_size, bool tx, bool auto_seq) |
| 231 | { |
| 232 | struct ieee80211_local *local = sta->sdata->local; |
| 233 | struct tid_ampdu_rx *tid_agg_rx; |
| 234 | int i, ret = -EOPNOTSUPP; |
| 235 | u16 status = WLAN_STATUS_REQUEST_DECLINED; |
| 236 | |
| 237 | if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { |
| 238 | ht_dbg(sta->sdata, |
| 239 | "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", |
| 240 | sta->sta.addr, tid); |
| 241 | goto end_no_lock; |
| 242 | } |
| 243 | |
| 244 | /* sanity check for incoming parameters: |
| 245 | * check if configuration can support the BA policy |
| 246 | * and if buffer size does not exceeds max value */ |
| 247 | /* XXX: check own ht delayed BA capability?? */ |
| 248 | if (((ba_policy != 1) && |
| 249 | (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || |
| 250 | (buf_size > IEEE80211_MAX_AMPDU_BUF)) { |
| 251 | status = WLAN_STATUS_INVALID_QOS_PARAM; |
| 252 | ht_dbg_ratelimited(sta->sdata, |
| 253 | "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", |
| 254 | sta->sta.addr, tid, ba_policy, buf_size); |
| 255 | goto end_no_lock; |
| 256 | } |
| 257 | /* determine default buffer size */ |
| 258 | if (buf_size == 0) |
| 259 | buf_size = IEEE80211_MAX_AMPDU_BUF; |
| 260 | |
| 261 | /* make sure the size doesn't exceed the maximum supported by the hw */ |
| 262 | if (buf_size > local->hw.max_rx_aggregation_subframes) |
| 263 | buf_size = local->hw.max_rx_aggregation_subframes; |
| 264 | |
| 265 | /* examine state machine */ |
| 266 | mutex_lock(&sta->ampdu_mlme.mtx); |
| 267 | |
| 268 | if (sta->ampdu_mlme.tid_rx[tid]) { |
| 269 | ht_dbg_ratelimited(sta->sdata, |
| 270 | "unexpected AddBA Req from %pM on tid %u\n", |
| 271 | sta->sta.addr, tid); |
| 272 | |
| 273 | /* delete existing Rx BA session on the same tid */ |
| 274 | ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, |
| 275 | WLAN_STATUS_UNSPECIFIED_QOS, |
| 276 | false); |
| 277 | } |
| 278 | |
| 279 | /* prepare A-MPDU MLME for Rx aggregation */ |
| 280 | tid_agg_rx = kmalloc(sizeof(struct tid_ampdu_rx), GFP_KERNEL); |
| 281 | if (!tid_agg_rx) |
| 282 | goto end; |
| 283 | |
| 284 | spin_lock_init(&tid_agg_rx->reorder_lock); |
| 285 | |
| 286 | /* rx timer */ |
| 287 | tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired; |
| 288 | tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid]; |
| 289 | init_timer_deferrable(&tid_agg_rx->session_timer); |
| 290 | |
| 291 | /* rx reorder timer */ |
| 292 | tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired; |
| 293 | tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid]; |
| 294 | init_timer(&tid_agg_rx->reorder_timer); |
| 295 | |
| 296 | /* prepare reordering buffer */ |
| 297 | tid_agg_rx->reorder_buf = |
| 298 | kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); |
| 299 | tid_agg_rx->reorder_time = |
| 300 | kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); |
| 301 | if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { |
| 302 | kfree(tid_agg_rx->reorder_buf); |
| 303 | kfree(tid_agg_rx->reorder_time); |
| 304 | kfree(tid_agg_rx); |
| 305 | goto end; |
| 306 | } |
| 307 | |
| 308 | for (i = 0; i < buf_size; i++) |
| 309 | __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); |
| 310 | |
| 311 | ret = drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_START, |
| 312 | &sta->sta, tid, &start_seq_num, 0); |
| 313 | ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", |
| 314 | sta->sta.addr, tid, ret); |
| 315 | if (ret) { |
| 316 | kfree(tid_agg_rx->reorder_buf); |
| 317 | kfree(tid_agg_rx->reorder_time); |
| 318 | kfree(tid_agg_rx); |
| 319 | goto end; |
| 320 | } |
| 321 | |
| 322 | /* update data */ |
| 323 | tid_agg_rx->dialog_token = dialog_token; |
| 324 | tid_agg_rx->ssn = start_seq_num; |
| 325 | tid_agg_rx->head_seq_num = start_seq_num; |
| 326 | tid_agg_rx->buf_size = buf_size; |
| 327 | tid_agg_rx->timeout = timeout; |
| 328 | tid_agg_rx->stored_mpdu_num = 0; |
| 329 | tid_agg_rx->auto_seq = auto_seq; |
| 330 | status = WLAN_STATUS_SUCCESS; |
| 331 | |
| 332 | /* activate it for RX */ |
| 333 | rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); |
| 334 | |
| 335 | if (timeout) { |
| 336 | mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); |
| 337 | tid_agg_rx->last_rx = jiffies; |
| 338 | } |
| 339 | |
| 340 | end: |
| 341 | mutex_unlock(&sta->ampdu_mlme.mtx); |
| 342 | |
| 343 | end_no_lock: |
| 344 | if (tx) |
| 345 | ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid, |
| 346 | dialog_token, status, 1, buf_size, |
| 347 | timeout); |
| 348 | } |
| 349 | |
| 350 | void ieee80211_process_addba_request(struct ieee80211_local *local, |
| 351 | struct sta_info *sta, |
| 352 | struct ieee80211_mgmt *mgmt, |
| 353 | size_t len) |
| 354 | { |
| 355 | u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; |
| 356 | u8 dialog_token; |
| 357 | |
| 358 | /* extract session parameters from addba request frame */ |
| 359 | dialog_token = mgmt->u.action.u.addba_req.dialog_token; |
| 360 | timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); |
| 361 | start_seq_num = |
| 362 | le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; |
| 363 | |
| 364 | capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); |
| 365 | ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; |
| 366 | tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; |
| 367 | buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; |
| 368 | |
| 369 | __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, |
| 370 | start_seq_num, ba_policy, tid, |
| 371 | buf_size, true, false); |
| 372 | } |
| 373 | |
| 374 | void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif, |
| 375 | const u8 *addr, u16 tid) |
| 376 | { |
| 377 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
| 378 | struct ieee80211_local *local = sdata->local; |
| 379 | struct ieee80211_rx_agg *rx_agg; |
| 380 | struct sk_buff *skb = dev_alloc_skb(0); |
| 381 | |
| 382 | if (unlikely(!skb)) |
| 383 | return; |
| 384 | |
| 385 | rx_agg = (struct ieee80211_rx_agg *) &skb->cb; |
| 386 | memcpy(&rx_agg->addr, addr, ETH_ALEN); |
| 387 | rx_agg->tid = tid; |
| 388 | |
| 389 | skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START; |
| 390 | skb_queue_tail(&sdata->skb_queue, skb); |
| 391 | ieee80211_queue_work(&local->hw, &sdata->work); |
| 392 | } |
| 393 | EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl); |
| 394 | |
| 395 | void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif, |
| 396 | const u8 *addr, u16 tid) |
| 397 | { |
| 398 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
| 399 | struct ieee80211_local *local = sdata->local; |
| 400 | struct ieee80211_rx_agg *rx_agg; |
| 401 | struct sk_buff *skb = dev_alloc_skb(0); |
| 402 | |
| 403 | if (unlikely(!skb)) |
| 404 | return; |
| 405 | |
| 406 | rx_agg = (struct ieee80211_rx_agg *) &skb->cb; |
| 407 | memcpy(&rx_agg->addr, addr, ETH_ALEN); |
| 408 | rx_agg->tid = tid; |
| 409 | |
| 410 | skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP; |
| 411 | skb_queue_tail(&sdata->skb_queue, skb); |
| 412 | ieee80211_queue_work(&local->hw, &sdata->work); |
| 413 | } |
| 414 | EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl); |