@@ -146,6 +146,13 @@ static int ___ieee80211_stop_tx_ba_sessi
if (WARN_ON(!tid_tx))
return -ENOENT;
+ if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
+ /* not even started yet! */
+ rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], NULL);
+ call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
+ return 0;
+ }
+
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
sta->sta.addr, tid);
@@ -255,6 +262,94 @@ ieee80211_wake_queue_agg(struct ieee8021
__release(agg_queue);
}
+static void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
+{
+ struct tid_ampdu_tx *tid_tx = sta->ampdu_mlme.tid_tx[tid];
+ struct ieee80211_local *local = sta->local;
+ struct ieee80211_sub_if_data *sdata = sta->sdata;
+ u16 start_seq_num;
+ int ret;
+
+ /*
+ * While we're asking the driver about the aggregation,
+ * stop the AC queue so that we don't have to worry
+ * about frames that came in while we were doing that,
+ * which would require us to put them to the AC pending
+ * afterwards which just makes the code more complex.
+ */
+ ieee80211_stop_queue_agg(local, tid);
+
+ clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
+
+ /*
+ * This might be off by one due to a race that we can't
+ * really prevent here without synchronize_net() which
+ * can't be called now.
+ */
+ start_seq_num = sta->tid_seq[tid] >> 4;
+
+ ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
+ &sta->sta, tid, &start_seq_num);
+ if (ret) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "BA request denied - HW unavailable for"
+ " tid %d\n", tid);
+#endif
+ rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], NULL);
+ ieee80211_wake_queue_agg(local, tid);
+ call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
+ return;
+ }
+
+ /* we can take packets again now */
+ ieee80211_wake_queue_agg(local, tid);
+
+ /* activate the timer for the recipient's addBA response */
+ mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
+#endif
+
+ sta->ampdu_mlme.addba_req_num[tid]++;
+
+ /* send AddBA request */
+ ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
+ tid_tx->dialog_token, start_seq_num,
+ 0x40, 5000);
+}
+
+void ieee80211_tx_ba_session_work(struct work_struct *work)
+{
+ struct sta_info *sta =
+ container_of(work, struct sta_info, ampdu_mlme.work);
+ struct tid_ampdu_tx *tid_tx;
+ int tid;
+
+ /*
+ * When this flag is set, new sessions should be
+ * blocked, and existing sessions will be torn
+ * down by the code that set the flag, so this
+ * need not run.
+ */
+ if (test_sta_flags(sta, WLAN_STA_BLOCK_BA))
+ return;
+
+ spin_lock_bh(&sta->lock);
+ for (tid = 0; tid < STA_TID_NUM; tid++) {
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
+ if (!tid_tx)
+ continue;
+
+ if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state))
+ ieee80211_tx_ba_session_handle_start(sta, tid);
+ else if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
+ &tid_tx->state))
+ ___ieee80211_stop_tx_ba_session(sta, tid,
+ WLAN_BACK_INITIATOR);
+ }
+ spin_unlock_bh(&sta->lock);
+}
+
int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
@@ -262,7 +357,6 @@ int ieee80211_start_tx_ba_session(struct
struct ieee80211_local *local = sdata->local;
struct tid_ampdu_tx *tid_tx;
int ret = 0;
- u16 start_seq_num;
trace_api_start_tx_ba_session(pubsta, tid);
@@ -316,15 +410,6 @@ int ieee80211_start_tx_ba_session(struct
goto err_unlock_sta;
}
- /*
- * While we're asking the driver about the aggregation,
- * stop the AC queue so that we don't have to worry
- * about frames that came in while we were doing that,
- * which would require us to put them to the AC pending
- * afterwards which just makes the code more complex.
- */
- ieee80211_stop_queue_agg(local, tid);
-
/* prepare A-MPDU MLME for Tx aggregation */
tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
if (!tid_tx) {
@@ -334,59 +419,27 @@ int ieee80211_start_tx_ba_session(struct
tid);
#endif
ret = -ENOMEM;
- goto err_wake_queue;
+ goto err_unlock_sta;
}
skb_queue_head_init(&tid_tx->pending);
+ __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
/* Tx timer */
tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
init_timer(&tid_tx->addba_resp_timer);
- start_seq_num = sta->tid_seq[tid] >> 4;
-
- ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
- pubsta, tid, &start_seq_num);
- if (ret) {
-#ifdef CONFIG_MAC80211_HT_DEBUG
- printk(KERN_DEBUG "BA request denied - HW unavailable for"
- " tid %d\n", tid);
-#endif /* CONFIG_MAC80211_HT_DEBUG */
- goto err_free;
- }
-
- rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
-
- /* Driver vetoed or OKed, but we can take packets again now */
- ieee80211_wake_queue_agg(local, tid);
-
- /* activate the timer for the recipient's addBA response */
- tid_tx->addba_resp_timer.expires = jiffies + ADDBA_RESP_INTERVAL;
- add_timer(&tid_tx->addba_resp_timer);
-#ifdef CONFIG_MAC80211_HT_DEBUG
- printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
-#endif
-
- /* prepare tid data */
+ /* assign a dialog token */
sta->ampdu_mlme.dialog_token_allocator++;
tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
- tid_tx->ssn = start_seq_num;
- sta->ampdu_mlme.addba_req_num[tid]++;
+ ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
- spin_unlock_bh(&sta->lock);
+ /* finally, assign it to the array */
+ rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
- /* send AddBA request */
- ieee80211_send_addba_request(sdata, pubsta->addr, tid,
- tid_tx->dialog_token, tid_tx->ssn,
- 0x40, 5000);
- return 0;
-
- err_free:
- kfree(tid_tx);
- err_wake_queue:
- ieee80211_wake_queue_agg(local, tid);
+ /* this flow continues off the work */
err_unlock_sta:
spin_unlock_bh(&sta->lock);
return ret;
@@ -534,8 +587,7 @@ int __ieee80211_stop_tx_ba_session(struc
spin_lock_bh(&sta->lock);
tid_tx = sta->ampdu_mlme.tid_tx[tid];
- /* check if the TID is in aggregation */
- if (!tid_tx || !test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
+ if (!tid_tx) {
ret = -ENOENT;
goto unlock;
}
@@ -552,6 +604,8 @@ int ieee80211_stop_tx_ba_session(struct
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);
@@ -561,7 +615,26 @@ int ieee80211_stop_tx_ba_session(struct
if (tid >= STA_TID_NUM)
return -EINVAL;
- return __ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
+ spin_lock_bh(&sta->lock);
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
+
+ if (!tid_tx) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+
+ 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);
@@ -67,6 +67,8 @@ enum ieee80211_sta_info_flags {
#define HT_AGG_STATE_RESPONSE_RECEIVED 1
#define HT_AGG_STATE_OPERATIONAL 2
#define HT_AGG_STATE_STOPPING 3
+#define HT_AGG_STATE_WANT_START 4
+#define HT_AGG_STATE_WANT_STOP 5
/**
* struct tid_ampdu_tx - TID aggregation information (Tx).
@@ -74,7 +76,6 @@ enum ieee80211_sta_info_flags {
* @rcu_head: rcu head for freeing structure
* @addba_resp_timer: timer for peer's response to addba request
* @pending: pending frames queue -- use sta's spinlock to protect
- * @ssn: Starting Sequence Number expected to be aggregated.
* @dialog_token: dialog token for aggregation session
* @state: session state (see above)
* @stop_initiator: initiator of a session stop
@@ -92,7 +93,6 @@ struct tid_ampdu_tx {
struct timer_list addba_resp_timer;
struct sk_buff_head pending;
unsigned long state;
- u16 ssn;
u8 dialog_token;
u8 stop_initiator;
};
@@ -138,11 +138,13 @@ struct tid_ampdu_rx {
* @tid_tx: aggregation info for Tx per TID
* @addba_req_num: number of times addBA request has been sent.
* @dialog_token_allocator: dialog token enumerator for each new session;
+ * @work: work struct for starting/stopping aggregation
*/
struct sta_ampdu_mlme {
/* rx */
struct tid_ampdu_rx *tid_rx[STA_TID_NUM];
/* tx */
+ struct work_struct work;
struct tid_ampdu_tx *tid_tx[STA_TID_NUM];
u8 addba_req_num[STA_TID_NUM];
u8 dialog_token_allocator;
@@ -121,7 +121,7 @@ static ssize_t sta_agg_status_read(struc
p += scnprintf(p, sizeof(buf) + buf - p, "next dialog_token: %#02x\n",
sta->ampdu_mlme.dialog_token_allocator + 1);
p += scnprintf(p, sizeof(buf) + buf - p,
- "TID\t\tRX active\tDTKN\tSSN\t\tTX\tDTKN\tSSN\tpending\n");
+ "TID\t\tRX active\tDTKN\tSSN\t\tTX\tDTKN\tpending\n");
for (i = 0; i < STA_TID_NUM; i++) {
p += scnprintf(p, sizeof(buf) + buf - p, "%02d", i);
p += scnprintf(p, sizeof(buf) + buf - p, "\t\t%x",
@@ -138,9 +138,6 @@ static ssize_t sta_agg_status_read(struc
p += scnprintf(p, sizeof(buf) + buf - p, "\t%#.2x",
sta->ampdu_mlme.tid_tx[i] ?
sta->ampdu_mlme.tid_tx[i]->dialog_token : 0);
- p += scnprintf(p, sizeof(buf) + buf - p, "\t%#.3x",
- sta->ampdu_mlme.tid_tx[i] ?
- sta->ampdu_mlme.tid_tx[i]->ssn : 0);
p += scnprintf(p, sizeof(buf) + buf - p, "\t%03d",
sta->ampdu_mlme.tid_tx[i] ?
skb_queue_len(&sta->ampdu_mlme.tid_tx[i]->pending) : 0);
@@ -1102,6 +1102,11 @@ static bool ieee80211_tx_prep_agg(struct
if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
info->flags |= IEEE80211_TX_CTL_AMPDU;
+ } else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
+ /*
+ * nothing -- this aggregation session is being started
+ * but that might still fail with the driver
+ */
} else {
spin_lock(&tx->sta->lock);
/*
@@ -1120,6 +1120,7 @@ int __ieee80211_stop_tx_ba_session(struc
enum ieee80211_back_parties initiator);
void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid);
void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid);
+void ieee80211_tx_ba_session_work(struct work_struct *work);
/* Spectrum management */
void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata,
@@ -235,6 +235,7 @@ struct sta_info *sta_info_alloc(struct i
spin_lock_init(&sta->lock);
spin_lock_init(&sta->flaglock);
INIT_WORK(&sta->drv_unblock_wk, sta_unblock);
+ INIT_WORK(&sta->ampdu_mlme.work, ieee80211_tx_ba_session_work);
memcpy(sta->sta.addr, addr, ETH_ALEN);
sta->local = local;
@@ -105,6 +105,8 @@ void ieee80211_sta_tear_down_BA_sessions
{
int i;
+ cancel_work_sync(&sta->ampdu_mlme.work);
+
for (i = 0; i < STA_TID_NUM; i++) {
__ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR);
__ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,