int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
enum ieee80211_agg_stop_reason reason)
{
struct ieee80211_local *local = sta->local;
struct tid_ampdu_tx *tid_tx;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.tid = tid,
.buf_size = 0,
.amsdu = false,
.timeout = 0,
.ssn = 0,
};
int ret;
lockdep_assert_held(&sta->ampdu_mlme.mtx);
switch (reason) {
case AGG_STOP_DECLINED:
case AGG_STOP_LOCAL_REQUEST:
case AGG_STOP_PEER_REQUEST:
params.action = IEEE80211_AMPDU_TX_STOP_CONT;
break;
case AGG_STOP_DESTROY_STA:
params.action = IEEE80211_AMPDU_TX_STOP_FLUSH;
break;
default:
WARN_ON_ONCE(1);
return -EINVAL;
}
spin_lock_bh(&sta->lock);
/* free struct pending for start, if present */
tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
kfree(tid_tx);
sta->ampdu_mlme.tid_start_tx[tid] = NULL;
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
if (!tid_tx) {
spin_unlock_bh(&sta->lock);
return -ENOENT;
}
/*
* if we're already stopping ignore any new requests to stop
* unless we're destroying it in which case notify the driver
*/
if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
spin_unlock_bh(&sta->lock);
if (reason != AGG_STOP_DESTROY_STA)
return -EALREADY;
params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT;
ret = drv_ampdu_action(local, sta->sdata, ¶ms);
WARN_ON_ONCE(ret);
return 0;
}
if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
/* not even started yet! */
ieee80211_assign_tid_tx(sta, tid, NULL);
spin_unlock_bh(&sta->lock);
kfree_rcu(tid_tx, rcu_head);
return 0;
}
set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
spin_unlock_bh(&sta->lock);
ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n",
sta->sta.addr, tid);
del_timer_sync(&tid_tx->addba_resp_timer);
del_timer_sync(&tid_tx->session_timer);
/*
* After this packets are no longer handed right through
* to the driver but are put onto tid_tx->pending instead,
* with locking to ensure proper access.
*/
clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
/*
* There might be a few packets being processed right now (on
* another CPU) that have already gotten past the aggregation
* check when it was still OPERATIONAL and consequently have
* IEEE80211_TX_CTL_AMPDU set. In that case, this code might
* call into the driver at the same time or even before the
* TX paths calls into it, which could confuse the driver.
*
* Wait for all currently running TX paths to finish before
* telling the driver. New packets will not go through since
* the aggregation session is no longer OPERATIONAL.
*/
synchronize_net();
tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ?
WLAN_BACK_RECIPIENT :
WLAN_BACK_INITIATOR;
tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
ret = drv_ampdu_action(local, sta->sdata, ¶ms);
/* HW shall not deny going back to legacy */
if (WARN_ON(ret)) {
/*
* We may have pending packets get stuck in this case...
* Not bothering with a workaround for now.
*/
}
/*
* In the case of AGG_STOP_DESTROY_STA, the driver won't
* necessarily call ieee80211_stop_tx_ba_cb(), so this may
* seem like we can leave the tid_tx data pending forever.
* This is true, in a way, but "forever" is only until the
* station struct is actually destroyed. In the meantime,
* leaving it around ensures that we don't transmit packets
* to the driver on this TID which might confuse it.
*/
return 0;
}
/*
* After sending add Block Ack request we activated a timer until
* add Block Ack response will arrive from the recipient.
* If this timer expires sta_addba_resp_timer_expired will be executed.
*/
static void sta_addba_resp_timer_expired(struct timer_list *t)
{
struct tid_ampdu_tx *tid_tx_timer =
from_timer(tid_tx_timer, t, addba_resp_timer);
struct sta_info *sta = tid_tx_timer->sta;
u8 tid = tid_tx_timer->tid;
struct tid_ampdu_tx *tid_tx;
/* check if the TID waits for addBA response */
rcu_read_lock();
tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
if (!tid_tx ||
test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
rcu_read_unlock();
ht_dbg(sta->sdata,
"timer expired on %pM tid %d not expecting addBA response\n",
sta->sta.addr, tid);
return;
}
ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n",
sta->sta.addr, tid);
ieee80211_stop_tx_ba_session(&sta->sta, tid);
rcu_read_unlock();
}
void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.action = IEEE80211_AMPDU_TX_START,
.tid = tid,
.buf_size = 0,
.amsdu = false,
.timeout = 0,
};
int ret;
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
/*
* Start queuing up packets for this aggregation session.
* We're going to release them once the driver is OK with
* that.
*/
clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
ieee80211_agg_stop_txq(sta, tid);
/*
* Make sure no packets are being processed. This ensures that
* we have a valid starting sequence number and that in-flight
* packets have been flushed out and no packets for this TID
* will go into the driver during the ampdu_action call.
*/
synchronize_net();
params.ssn = sta->tid_seq[tid] >> 4;
ret = drv_ampdu_action(local, sdata, ¶ms);
if (ret) {
ht_dbg(sdata,
"BA request denied - HW unavailable for %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
ieee80211_agg_splice_packets(sdata, tid_tx, tid);
ieee80211_assign_tid_tx(sta, tid, NULL);
ieee80211_agg_splice_finish(sdata, tid);
spin_unlock_bh(&sta->lock);
ieee80211_agg_start_txq(sta, tid, false);
kfree_rcu(tid_tx, rcu_head);
return;
}
/* activate the timer for the recipient's addBA response */
mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
sta->ampdu_mlme.addba_req_num[tid]++;
spin_unlock_bh(&sta->lock);
/* send AddBA request */
ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
tid_tx->dialog_token, params.ssn,
IEEE80211_MAX_AMPDU_BUF,
tid_tx->timeout);
}
/*
* After accepting the AddBA Response we activated a timer,
* resetting it after each frame that we send.
*/
static void sta_tx_agg_session_timer_expired(struct timer_list *t)
{
struct tid_ampdu_tx *tid_tx_timer =
from_timer(tid_tx_timer, t, session_timer);
struct sta_info *sta = tid_tx_timer->sta;
u8 tid = tid_tx_timer->tid;
struct tid_ampdu_tx *tid_tx;
unsigned long timeout;
rcu_read_lock();
tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
rcu_read_unlock();
return;
}
timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
if (time_is_after_jiffies(timeout)) {
mod_timer(&tid_tx->session_timer, timeout);
rcu_read_unlock();
return;
}
rcu_read_unlock();
ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
sta->sta.addr, tid);
ieee80211_stop_tx_ba_session(&sta->sta, tid);
}
int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
u16 timeout)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
struct tid_ampdu_tx *tid_tx;
int ret = 0;
trace_api_start_tx_ba_session(pubsta, tid);
if (WARN(sta->reserved_tid == tid,
"Requested to start BA session on reserved tid=%d", tid))
return -EINVAL;
if (!pubsta->ht_cap.ht_supported)
return -EINVAL;
if (WARN_ON_ONCE(!local->ops->ampdu_action))
return -EINVAL;
if ((tid >= IEEE80211_NUM_TIDS) ||
!ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) ||
ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW))
return -EINVAL;
if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID))
return -EINVAL;
ht_dbg(sdata, "Open BA session requested for %pM tid %u\n",
pubsta->addr, tid);
if (sdata->vif.type != NL80211_IFTYPE_STATION &&
sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
sdata->vif.type != NL80211_IFTYPE_AP &&
sdata->vif.type != NL80211_IFTYPE_ADHOC)
return -EINVAL;
if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
ht_dbg(sdata,
"BA sessions blocked - Denying BA session request %pM tid %d\n",
sta->sta.addr, tid);
return -EINVAL;
}
/*
* 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
* member of an IBSS, and has no other existing Block Ack agreement
* with the recipient STA, then the initiating STA shall transmit a
* Probe Request frame to the recipient STA and shall not transmit an
* ADDBA Request frame unless it receives a Probe Response frame
* from the recipient within dot11ADDBAFailureTimeout.
*
* The probe request mechanism for ADDBA is currently not implemented,
* but we only build up Block Ack session with HT STAs. This information
* is set when we receive a bss info from a probe response or a beacon.
*/
if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
!sta->sta.ht_cap.ht_supported) {
ht_dbg(sdata,
"BA request denied - IBSS STA %pM does not advertise HT support\n",
pubsta->addr);
return -EINVAL;
}
spin_lock_bh(&sta->lock);
/* we have tried too many times, receiver does not want A-MPDU */
if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
ret = -EBUSY;
goto err_unlock_sta;
}
/*
* if we have tried more than HT_AGG_BURST_RETRIES times we
* will spread our requests in time to avoid stalling connection
* for too long
*/
if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES &&
time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] +
HT_AGG_RETRIES_PERIOD)) {
ht_dbg(sdata,
"BA request denied - %d failed requests on %pM tid %u\n",
sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid);
ret = -EBUSY;
goto err_unlock_sta;
}
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
/* check if the TID is not in aggregation flow already */
if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
ht_dbg(sdata,
"BA request denied - session is not idle on %pM tid %u\n",
sta->sta.addr, tid);
ret = -EAGAIN;
goto err_unlock_sta;
}
/* prepare A-MPDU MLME for Tx aggregation */
tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
if (!tid_tx) {
ret = -ENOMEM;
goto err_unlock_sta;
}
skb_queue_head_init(&tid_tx->pending);
__set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
tid_tx->timeout = timeout;
tid_tx->sta = sta;
tid_tx->tid = tid;
/* response timer */
timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0);
/* tx timer */
timer_setup(&tid_tx->session_timer,
sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE);
/* assign a dialog token */
sta->ampdu_mlme.dialog_token_allocator++;
tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
/*
* Finally, assign it to the start array; the work item will
* collect it and move it to the normal array.
*/
sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
/* this flow continues off the work */
err_unlock_sta:
spin_unlock_bh(&sta->lock);
return ret;
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
struct sta_info *sta, u16 tid)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.action = IEEE80211_AMPDU_TX_OPERATIONAL,
.tid = tid,
.timeout = 0,
.ssn = 0,
};
lockdep_assert_held(&sta->ampdu_mlme.mtx);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
params.buf_size = tid_tx->buf_size;
params.amsdu = tid_tx->amsdu;
ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n",
sta->sta.addr, tid);
drv_ampdu_action(local, sta->sdata, ¶ms);
/*
* synchronize with TX path, while splicing the TX path
* should block so it won't put more packets onto pending.
*/
spin_lock_bh(&sta->lock);
ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
/*
* Now mark as operational. This will be visible
* in the TX path, and lets it go lock-free in
* the common case.
*/
set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
ieee80211_agg_splice_finish(sta->sdata, tid);
spin_unlock_bh(&sta->lock);
ieee80211_agg_start_txq(sta, tid, true);
}
void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid,
struct tid_ampdu_tx *tid_tx)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
return;
if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
ieee80211_agg_tx_operational(local, sta, tid);
}
static struct tid_ampdu_tx *
ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata,
const u8 *ra, u16 tid, struct sta_info **sta)
{
struct tid_ampdu_tx *tid_tx;
if (tid >= IEEE80211_NUM_TIDS) {
ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
tid, IEEE80211_NUM_TIDS);
return NULL;
}
*sta = sta_info_get_bss(sdata, ra);
if (!*sta) {
ht_dbg(sdata, "Could not find station: %pM\n", ra);
return NULL;
}
tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]);
if (WARN_ON(!tid_tx))
ht_dbg(sdata, "addBA was not requested!\n");
return tid_tx;
}
void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
const u8 *ra, u16 tid)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
struct tid_ampdu_tx *tid_tx;
trace_api_start_tx_ba_cb(sdata, ra, tid);
rcu_read_lock();
tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
if (!tid_tx)
goto out;
set_bit(HT_AGG_STATE_START_CB, &tid_tx->state);
ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
out:
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
enum ieee80211_agg_stop_reason reason)
{
int ret;
mutex_lock(&sta->ampdu_mlme.mtx);
ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason);
mutex_unlock(&sta->ampdu_mlme.mtx);
return ret;
}
int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
struct tid_ampdu_tx *tid_tx;
int ret = 0;
trace_api_stop_tx_ba_session(pubsta, tid);
if (!local->ops->ampdu_action)
return -EINVAL;
if (tid >= IEEE80211_NUM_TIDS)
return -EINVAL;
spin_lock_bh(&sta->lock);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
if (!tid_tx) {
ret = -ENOENT;
goto unlock;
}
WARN(sta->reserved_tid == tid,
"Requested to stop BA session on reserved tid=%d", tid);
if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
/* already in progress stopping it */
ret = 0;
goto unlock;
}
set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
unlock:
spin_unlock_bh(&sta->lock);
return ret;
}
EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid,
struct tid_ampdu_tx *tid_tx)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
bool send_delba = false;
ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
ht_dbg(sdata,
"unexpected callback to A-MPDU stop for %pM tid %d\n",
sta->sta.addr, tid);
goto unlock_sta;
}
if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
send_delba = true;
ieee80211_remove_tid_tx(sta, tid);
unlock_sta:
spin_unlock_bh(&sta->lock);
if (send_delba)
ieee80211_send_delba(sdata, sta->sta.addr, tid,
WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
}
void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
const u8 *ra, u16 tid)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
struct tid_ampdu_tx *tid_tx;
trace_api_stop_tx_ba_cb(sdata, ra, tid);
rcu_read_lock();
tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
if (!tid_tx)
goto out;
set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state);
ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
out:
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
void ieee80211_process_addba_resp(struct ieee80211_local *local,
struct sta_info *sta,
struct ieee80211_mgmt *mgmt,
size_t len)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_txq *txq;
u16 capab, tid;
u8 buf_size;
bool amsdu;
capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK;
tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
txq = sta->sta.txq[tid];
if (!amsdu && txq)
set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
mutex_lock(&sta->ampdu_mlme.mtx);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
if (!tid_tx)
goto out;
if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n",
sta->sta.addr, tid);
goto out;
}
del_timer_sync(&tid_tx->addba_resp_timer);
ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n",
sta->sta.addr, tid);
/*
* addba_resp_timer may have fired before we got here, and
* caused WANT_STOP to be set. If the stop then was already
* processed further, STOPPING might be set.
*/
if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
ht_dbg(sta->sdata,
"got addBA resp for %pM tid %d but we already gave up\n",
sta->sta.addr, tid);
goto out;
}
/*
* IEEE 802.11-2007 7.3.1.14:
* In an ADDBA Response frame, when the Status Code field
* is set to 0, the Buffer Size subfield is set to a value
* of at least 1.
*/
if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
== WLAN_STATUS_SUCCESS && buf_size) {
if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
&tid_tx->state)) {
/* ignore duplicate response */
goto out;
}
tid_tx->buf_size = buf_size;
tid_tx->amsdu = amsdu;
if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
ieee80211_agg_tx_operational(local, sta, tid);
sta->ampdu_mlme.addba_req_num[tid] = 0;
if (tid_tx->timeout) {
mod_timer(&tid_tx->session_timer,
TU_TO_EXP_TIME(tid_tx->timeout));
tid_tx->last_tx = jiffies;
}
} else {
___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
}
out:
mutex_unlock(&sta->ampdu_mlme.mtx);
}
void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
u16 start_seq_num;
int ret;
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
/*
* Start queuing up packets for this aggregation session.
* We're going to release them once the driver is OK with
* that.
*/
clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
ieee80211_agg_stop_txq(sta, tid);
/*
* Make sure no packets are being processed. This ensures that
* we have a valid starting sequence number and that in-flight
* packets have been flushed out and no packets for this TID
* will go into the driver during the ampdu_action call.
*/
synchronize_net();
start_seq_num = sta->tid_seq[tid] >> 4;
ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
&sta->sta, tid, &start_seq_num, 0, false);
if (ret) {
ht_dbg(sdata,
"BA request denied - HW unavailable for %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
ieee80211_agg_splice_packets(sdata, tid_tx, tid);
ieee80211_assign_tid_tx(sta, tid, NULL);
ieee80211_agg_splice_finish(sdata, tid);
spin_unlock_bh(&sta->lock);
ieee80211_agg_start_txq(sta, tid, false);
kfree_rcu(tid_tx, rcu_head);
return;
}
/* activate the timer for the recipient's addBA response */
mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
sta->ampdu_mlme.addba_req_num[tid]++;
spin_unlock_bh(&sta->lock);
/* send AddBA request */
ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
tid_tx->dialog_token, start_seq_num,
local->hw.max_tx_aggregation_subframes,
tid_tx->timeout);
}
void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.action = IEEE80211_AMPDU_TX_START,
.tid = tid,
.buf_size = 0,
.amsdu = false,
.timeout = 0,
};
int ret;
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
/*
* Start queuing up packets for this aggregation session.
* We're going to release them once the driver is OK with
* that.
*/
clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
ieee80211_agg_stop_txq(sta, tid);
/*
* Make sure no packets are being processed. This ensures that
* we have a valid starting sequence number and that in-flight
* packets have been flushed out and no packets for this TID
* will go into the driver during the ampdu_action call.
*/
synchronize_net();
params.ssn = sta->tid_seq[tid] >> 4;
ret = drv_ampdu_action(local, sdata, ¶ms);
if (ret) {
ht_dbg(sdata,
"BA request denied - HW unavailable for %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
ieee80211_agg_splice_packets(sdata, tid_tx, tid);
ieee80211_assign_tid_tx(sta, tid, NULL);
ieee80211_agg_splice_finish(sdata, tid);
spin_unlock_bh(&sta->lock);
ieee80211_agg_start_txq(sta, tid, false);
kfree_rcu(tid_tx, rcu_head);
return;
}
/* activate the timer for the recipient's addBA response */
mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
sta->ampdu_mlme.addba_req_num[tid]++;
spin_unlock_bh(&sta->lock);
/* send AddBA request */
ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
tid_tx->dialog_token, params.ssn,
IEEE80211_MAX_AMPDU_BUF,
tid_tx->timeout);
}
/*
* After accepting the AddBA Response we activated a timer,
* resetting it after each frame that we send.
*/
static void sta_tx_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_tx *tid_tx;
unsigned long timeout;
rcu_read_lock();
tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[*ptid]);
if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
rcu_read_unlock();
return;
}
timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
if (time_is_after_jiffies(timeout)) {
mod_timer(&tid_tx->session_timer, timeout);
rcu_read_unlock();
return;
}
rcu_read_unlock();
ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
sta->sta.addr, (u16)*ptid);
ieee80211_stop_tx_ba_session(&sta->sta, *ptid);
}