diff options
Diffstat (limited to 'kernel/net/mac80211/agg-rx.c')
-rw-r--r-- | kernel/net/mac80211/agg-rx.c | 426 |
1 files changed, 426 insertions, 0 deletions
diff --git a/kernel/net/mac80211/agg-rx.c b/kernel/net/mac80211/agg-rx.c new file mode 100644 index 000000000..5c564a68f --- /dev/null +++ b/kernel/net/mac80211/agg-rx.c @@ -0,0 +1,426 @@ +/* + * 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; + + for (i = 0; i < tid_rx->buf_size; i++) + __skb_queue_purge(&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); + + /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */ + spin_lock_bh(&tid_rx->reorder_lock); + tid_rx->removed = true; + spin_unlock_bh(&tid_rx->reorder_lock); + del_timer_sync(&tid_rx->reorder_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_start_rx_ba_session(struct sta_info *sta, + u8 dialog_token, u16 timeout, + u16 start_seq_num, u16 ba_policy, u16 tid, + u16 buf_size, bool tx, bool auto_seq) +{ + struct ieee80211_local *local = sta->sdata->local; + struct tid_ampdu_rx *tid_agg_rx; + int i, ret = -EOPNOTSUPP; + u16 status = WLAN_STATUS_REQUEST_DECLINED; + + if (!sta->sta.ht_cap.ht_supported) { + ht_dbg(sta->sdata, + "STA %pM erroneously requests BA session on tid %d w/o QoS\n", + sta->sta.addr, tid); + /* send a response anyway, it's an error case if we get here */ + goto end_no_lock; + } + + 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", + sta->sta.addr, 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", + sta->sta.addr, 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_head), 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; + } + + for (i = 0; i < buf_size; i++) + __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); + + 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; + tid_agg_rx->auto_seq = auto_seq; + 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: + if (tx) + ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid, + dialog_token, status, 1, buf_size, + timeout); +} + +void ieee80211_process_addba_request(struct ieee80211_local *local, + struct sta_info *sta, + struct ieee80211_mgmt *mgmt, + size_t len) +{ + u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num; + u8 dialog_token; + + /* 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; + + __ieee80211_start_rx_ba_session(sta, dialog_token, timeout, + start_seq_num, ba_policy, tid, + buf_size, true, false); +} + +void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif, + const u8 *addr, u16 tid) +{ + struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); + struct ieee80211_local *local = sdata->local; + struct ieee80211_rx_agg *rx_agg; + struct sk_buff *skb = dev_alloc_skb(0); + + if (unlikely(!skb)) + return; + + rx_agg = (struct ieee80211_rx_agg *) &skb->cb; + memcpy(&rx_agg->addr, addr, ETH_ALEN); + rx_agg->tid = tid; + + skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START; + skb_queue_tail(&sdata->skb_queue, skb); + ieee80211_queue_work(&local->hw, &sdata->work); +} +EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl); + +void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif, + const u8 *addr, u16 tid) +{ + struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); + struct ieee80211_local *local = sdata->local; + struct ieee80211_rx_agg *rx_agg; + struct sk_buff *skb = dev_alloc_skb(0); + + if (unlikely(!skb)) + return; + + rx_agg = (struct ieee80211_rx_agg *) &skb->cb; + memcpy(&rx_agg->addr, addr, ETH_ALEN); + rx_agg->tid = tid; + + skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP; + skb_queue_tail(&sdata->skb_queue, skb); + ieee80211_queue_work(&local->hw, &sdata->work); +} +EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl); |