/* * HT handling * * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> * Copyright 2007, Michael Wu <flamingice@sourmilk.net> * Copyright 2007-2010, Intel Corporation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ /** * DOC: RX A-MPDU aggregation * * Aggregation on the RX side requires only implementing the * @ampdu_action callback that is invoked to start/stop any * block-ack sessions for RX aggregation. * * When RX aggregation is started by the peer, the driver is * notified via @ampdu_action function, with the * %IEEE80211_AMPDU_RX_START action, and may reject the request * in which case a negative response is sent to the peer, if it * accepts it a positive response is sent. * * While the session is active, the device/driver are required * to de-aggregate frames and pass them up one by one to mac80211, * which will handle the reorder buffer. * * When the aggregation session is stopped again by the peer or * ourselves, the driver's @ampdu_action function will be called * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the * call must not fail. */ #include <linux/ieee80211.h> #include <linux/slab.h> #include <linux/export.h> #include <net/mac80211.h> #include "ieee80211_i.h" #include "driver-ops.h" static void ieee80211_free_tid_rx(struct rcu_head *h) { struct tid_ampdu_rx *tid_rx = container_of(h, struct tid_ampdu_rx, rcu_head); int i; del_timer_sync(&tid_rx->reorder_timer); for (i = 0; i < tid_rx->buf_size; i++) dev_kfree_skb(tid_rx->reorder_buf[i]); kfree(tid_rx->reorder_buf); kfree(tid_rx->reorder_time); kfree(tid_rx); } void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, u16 initiator, u16 reason, bool tx) { struct ieee80211_local *local = sta->local; struct tid_ampdu_rx *tid_rx; lockdep_assert_held(&sta->ampdu_mlme.mtx); tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid], lockdep_is_held(&sta->ampdu_mlme.mtx)); if (!tid_rx) return; RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL); ht_dbg(sta->sdata, "Rx BA session stop requested for %pM tid %u %s reason: %d\n", sta->sta.addr, tid, initiator == WLAN_BACK_RECIPIENT ? "recipient" : "inititator", (int)reason); if (drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_STOP, &sta->sta, tid, NULL, 0)) sdata_info(sta->sdata, "HW problem - can not stop rx aggregation for %pM tid %d\n", sta->sta.addr, tid); /* check if this is a self generated aggregation halt */ if (initiator == WLAN_BACK_RECIPIENT && tx) ieee80211_send_delba(sta->sdata, sta->sta.addr, tid, WLAN_BACK_RECIPIENT, reason); del_timer_sync(&tid_rx->session_timer); call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx); } void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, u16 initiator, u16 reason, bool tx) { mutex_lock(&sta->ampdu_mlme.mtx); ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx); mutex_unlock(&sta->ampdu_mlme.mtx); } void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap, const u8 *addr) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct sta_info *sta; int i; rcu_read_lock(); sta = sta_info_get_bss(sdata, addr); if (!sta) { rcu_read_unlock(); return; } for (i = 0; i < IEEE80211_NUM_TIDS; i++) if (ba_rx_bitmap & BIT(i)) set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested); ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); rcu_read_unlock(); } EXPORT_SYMBOL(ieee80211_stop_rx_ba_session); /* * After accepting the AddBA Request we activated a timer, * resetting it after each frame that arrives from the originator. */ static void sta_rx_agg_session_timer_expired(unsigned long data) { /* not an elegant detour, but there is no choice as the timer passes * only one argument, and various sta_info are needed here, so init * flow in sta_info_create gives the TID as data, while the timer_to_id * array gives the sta through container_of */ u8 *ptid = (u8 *)data; u8 *timer_to_id = ptid - *ptid; struct sta_info *sta = container_of(timer_to_id, struct sta_info, timer_to_tid[0]); struct tid_ampdu_rx *tid_rx; unsigned long timeout; rcu_read_lock(); tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]); if (!tid_rx) { rcu_read_unlock(); return; } timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); if (time_is_after_jiffies(timeout)) { mod_timer(&tid_rx->session_timer, timeout); rcu_read_unlock(); return; } rcu_read_unlock(); ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n", sta->sta.addr, (u16)*ptid); set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired); ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work); } static void sta_rx_agg_reorder_timer_expired(unsigned long data) { u8 *ptid = (u8 *)data; u8 *timer_to_id = ptid - *ptid; struct sta_info *sta = container_of(timer_to_id, struct sta_info, timer_to_tid[0]); rcu_read_lock(); ieee80211_release_reorder_timeout(sta, *ptid); rcu_read_unlock(); } static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid, u8 dialog_token, u16 status, u16 policy, u16 buf_size, u16 timeout) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_mgmt *mgmt; u16 capab; skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); if (!skb) return; skb_reserve(skb, local->hw.extra_tx_headroom); mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24); memset(mgmt, 0, 24); memcpy(mgmt->da, da, ETH_ALEN); memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); if (sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_AP_VLAN || sdata->vif.type == NL80211_IFTYPE_MESH_POINT) memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); else if (sdata->vif.type == NL80211_IFTYPE_STATION) memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_ACTION); skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp)); mgmt->u.action.category = WLAN_CATEGORY_BACK; mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP; mgmt->u.action.u.addba_resp.dialog_token = dialog_token; capab = (u16)(policy << 1); /* bit 1 aggregation policy */ capab |= (u16)(tid << 2); /* bit 5:2 TID number */ capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */ mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab); mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout); mgmt->u.action.u.addba_resp.status = cpu_to_le16(status); ieee80211_tx_skb(sdata, skb); } void ieee80211_process_addba_request(struct ieee80211_local *local, struct sta_info *sta, struct ieee80211_mgmt *mgmt, size_t len) { struct tid_ampdu_rx *tid_agg_rx; u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status; u8 dialog_token; int ret = -EOPNOTSUPP; /* extract session parameters from addba request frame */ dialog_token = mgmt->u.action.u.addba_req.dialog_token; timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout); start_seq_num = le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4; capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab); ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1; tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; status = WLAN_STATUS_REQUEST_DECLINED; if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { ht_dbg(sta->sdata, "Suspend in progress - Denying ADDBA request (%pM tid %d)\n", sta->sta.addr, tid); goto end_no_lock; } /* sanity check for incoming parameters: * check if configuration can support the BA policy * and if buffer size does not exceeds max value */ /* XXX: check own ht delayed BA capability?? */ if (((ba_policy != 1) && (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) || (buf_size > IEEE80211_MAX_AMPDU_BUF)) { status = WLAN_STATUS_INVALID_QOS_PARAM; ht_dbg_ratelimited(sta->sdata, "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n", mgmt->sa, tid, ba_policy, buf_size); goto end_no_lock; } /* determine default buffer size */ if (buf_size == 0) buf_size = IEEE80211_MAX_AMPDU_BUF; /* make sure the size doesn't exceed the maximum supported by the hw */ if (buf_size > local->hw.max_rx_aggregation_subframes) buf_size = local->hw.max_rx_aggregation_subframes; /* examine state machine */ mutex_lock(&sta->ampdu_mlme.mtx); if (sta->ampdu_mlme.tid_rx[tid]) { ht_dbg_ratelimited(sta->sdata, "unexpected AddBA Req from %pM on tid %u\n", mgmt->sa, tid); /* delete existing Rx BA session on the same tid */ ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, WLAN_STATUS_UNSPECIFIED_QOS, false); } /* prepare A-MPDU MLME for Rx aggregation */ tid_agg_rx = kmalloc(sizeof(struct tid_ampdu_rx), GFP_KERNEL); if (!tid_agg_rx) goto end; spin_lock_init(&tid_agg_rx->reorder_lock); /* rx timer */ tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired; tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid]; init_timer_deferrable(&tid_agg_rx->session_timer); /* rx reorder timer */ tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired; tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid]; init_timer(&tid_agg_rx->reorder_timer); /* prepare reordering buffer */ tid_agg_rx->reorder_buf = kcalloc(buf_size, sizeof(struct sk_buff *), GFP_KERNEL); tid_agg_rx->reorder_time = kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { kfree(tid_agg_rx->reorder_buf); kfree(tid_agg_rx->reorder_time); kfree(tid_agg_rx); goto end; } ret = drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_START, &sta->sta, tid, &start_seq_num, 0); ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", sta->sta.addr, tid, ret); if (ret) { kfree(tid_agg_rx->reorder_buf); kfree(tid_agg_rx->reorder_time); kfree(tid_agg_rx); goto end; } /* update data */ tid_agg_rx->dialog_token = dialog_token; tid_agg_rx->ssn = start_seq_num; tid_agg_rx->head_seq_num = start_seq_num; tid_agg_rx->buf_size = buf_size; tid_agg_rx->timeout = timeout; tid_agg_rx->stored_mpdu_num = 0; status = WLAN_STATUS_SUCCESS; /* activate it for RX */ rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx); if (timeout) { mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout)); tid_agg_rx->last_rx = jiffies; } end: mutex_unlock(&sta->ampdu_mlme.mtx); end_no_lock: ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid, dialog_token, status, 1, buf_size, timeout); }