aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--net/mac80211/agg-tx.c229
-rw-r--r--net/mac80211/debugfs_sta.c8
-rw-r--r--net/mac80211/ht.c9
-rw-r--r--net/mac80211/ieee80211_i.h2
-rw-r--r--net/mac80211/rc80211_minstrel_ht.c2
-rw-r--r--net/mac80211/sta_info.c12
-rw-r--r--net/mac80211/sta_info.h33
-rw-r--r--net/mac80211/tx.c88
8 files changed, 206 insertions, 177 deletions
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index c7b7ac4..7d8656d 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -125,25 +125,42 @@ void ieee80211_send_bar(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid, u1
ieee80211_tx_skb(sdata, skb);
}
-int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
- enum ieee80211_back_parties initiator)
+static void kfree_tid_tx(struct rcu_head *rcu_head)
+{
+ struct tid_ampdu_tx *tid_tx =
+ container_of(rcu_head, struct tid_ampdu_tx, rcu_head);
+
+ kfree(tid_tx);
+}
+
+static int ___ieee80211_stop_tx_ba_session(
+ struct sta_info *sta, u16 tid,
+ enum ieee80211_back_parties initiator)
{
struct ieee80211_local *local = sta->local;
+ struct tid_ampdu_tx *tid_tx = sta->ampdu_mlme.tid_tx[tid];
int ret;
- u8 *state;
+
+ lockdep_assert_held(&sta->lock);
+
+ if (WARN_ON(!tid_tx))
+ return -ENOENT;
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
sta->sta.addr, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
- state = &sta->ampdu_mlme.tid_state_tx[tid];
+ set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
- if (*state == HT_AGG_STATE_OPERATIONAL)
- sta->ampdu_mlme.addba_req_num[tid] = 0;
+ /*
+ * 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);
- *state = HT_AGG_STATE_REQ_STOP_BA_MSK |
- (initiator << HT_AGG_STATE_INITIATOR_SHIFT);
+ tid_tx->stop_initiator = initiator;
ret = drv_ampdu_action(local, sta->sdata,
IEEE80211_AMPDU_TX_STOP,
@@ -174,15 +191,13 @@ static void sta_addba_resp_timer_expired(unsigned long data)
u16 tid = *(u8 *)data;
struct sta_info *sta = container_of((void *)data,
struct sta_info, timer_to_tid[tid]);
- u8 *state;
-
- state = &sta->ampdu_mlme.tid_state_tx[tid];
+ struct tid_ampdu_tx *tid_tx;
/* check if the TID waits for addBA response */
spin_lock_bh(&sta->lock);
- if ((*state & (HT_ADDBA_REQUESTED_MSK | HT_ADDBA_RECEIVED_MSK |
- HT_AGG_STATE_REQ_STOP_BA_MSK)) !=
- HT_ADDBA_REQUESTED_MSK) {
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
+ if (!tid_tx ||
+ test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
spin_unlock_bh(&sta->lock);
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "timer expired on tid %d but we are not "
@@ -210,7 +225,7 @@ int ieee80211_start_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;
- u8 *state;
+ struct tid_ampdu_tx *tid_tx;
int ret = 0;
u16 start_seq_num;
@@ -256,9 +271,9 @@ int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
goto err_unlock_sta;
}
- state = &sta->ampdu_mlme.tid_state_tx[tid];
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
/* check if the TID is not in aggregation flow already */
- if (*state != HT_AGG_STATE_IDLE) {
+ if (tid_tx) {
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "BA request denied - session is not "
"idle on tid %u\n", tid);
@@ -279,9 +294,8 @@ int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
/* prepare A-MPDU MLME for Tx aggregation */
- sta->ampdu_mlme.tid_tx[tid] =
- kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
- if (!sta->ampdu_mlme.tid_tx[tid]) {
+ tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
+ if (!tid_tx) {
#ifdef CONFIG_MAC80211_HT_DEBUG
if (net_ratelimit())
printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
@@ -291,33 +305,27 @@ int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
goto err_wake_queue;
}
- skb_queue_head_init(&sta->ampdu_mlme.tid_tx[tid]->pending);
+ skb_queue_head_init(&tid_tx->pending);
/* Tx timer */
- sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
- sta_addba_resp_timer_expired;
- sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.data =
- (unsigned long)&sta->timer_to_tid[tid];
- init_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
-
- /* Ok, the Addba frame hasn't been sent yet, but if the driver calls the
- * call back right away, it must see that the flow has begun */
- *state |= HT_ADDBA_REQUESTED_MSK;
+ 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 */
- *state = HT_AGG_STATE_IDLE;
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_by_reason(
&local->hw, ieee80211_ac_from_tid(tid),
@@ -325,32 +333,30 @@ int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
spin_unlock(&local->ampdu_lock);
+ /* 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 */
sta->ampdu_mlme.dialog_token_allocator++;
- sta->ampdu_mlme.tid_tx[tid]->dialog_token =
- sta->ampdu_mlme.dialog_token_allocator;
- sta->ampdu_mlme.tid_tx[tid]->ssn = start_seq_num;
+ tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
+ tid_tx->ssn = start_seq_num;
+
+ sta->ampdu_mlme.addba_req_num[tid]++;
spin_unlock_bh(&sta->lock);
/* send AddBA request */
ieee80211_send_addba_request(sdata, pubsta->addr, tid,
- sta->ampdu_mlme.tid_tx[tid]->dialog_token,
- sta->ampdu_mlme.tid_tx[tid]->ssn,
+ tid_tx->dialog_token, tid_tx->ssn,
0x40, 5000);
- sta->ampdu_mlme.addba_req_num[tid]++;
- /* activate the timer for the recipient's addBA response */
- sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.expires =
- jiffies + ADDBA_RESP_INTERVAL;
- add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
-#ifdef CONFIG_MAC80211_HT_DEBUG
- printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
-#endif
return 0;
err_free:
- kfree(sta->ampdu_mlme.tid_tx[tid]);
- sta->ampdu_mlme.tid_tx[tid] = NULL;
+ kfree(tid_tx);
err_wake_queue:
ieee80211_wake_queue_by_reason(
&local->hw, ieee80211_ac_from_tid(tid),
@@ -368,7 +374,8 @@ EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
* local->ampdu_lock across both calls.
*/
static void ieee80211_agg_splice_packets(struct ieee80211_local *local,
- struct sta_info *sta, u16 tid)
+ struct tid_ampdu_tx *tid_tx,
+ u16 tid)
{
unsigned long flags;
u16 queue = ieee80211_ac_from_tid(tid);
@@ -377,31 +384,23 @@ static void ieee80211_agg_splice_packets(struct ieee80211_local *local,
&local->hw, queue,
IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
- if (!(sta->ampdu_mlme.tid_state_tx[tid] & HT_ADDBA_REQUESTED_MSK))
- return;
-
- if (WARN(!sta->ampdu_mlme.tid_tx[tid],
- "TID %d gone but expected when splicing aggregates from"
- "the pending queue\n", tid))
+ if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
+ " from the pending queue\n", tid))
return;
- if (!skb_queue_empty(&sta->ampdu_mlme.tid_tx[tid]->pending)) {
+ if (!skb_queue_empty(&tid_tx->pending)) {
spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
/* copy over remaining packets */
- skb_queue_splice_tail_init(
- &sta->ampdu_mlme.tid_tx[tid]->pending,
- &local->pending[queue]);
+ skb_queue_splice_tail_init(&tid_tx->pending,
+ &local->pending[queue]);
spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
}
}
-static void ieee80211_agg_splice_finish(struct ieee80211_local *local,
- struct sta_info *sta, u16 tid)
+static void ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
{
- u16 queue = ieee80211_ac_from_tid(tid);
-
ieee80211_wake_queue_by_reason(
- &local->hw, queue,
+ &local->hw, ieee80211_ac_from_tid(tid),
IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
}
@@ -409,19 +408,21 @@ static void ieee80211_agg_splice_finish(struct ieee80211_local *local,
static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
struct sta_info *sta, u16 tid)
{
+ lockdep_assert_held(&sta->lock);
+
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "Aggregation is on for tid %d\n", tid);
#endif
spin_lock(&local->ampdu_lock);
- ieee80211_agg_splice_packets(local, sta, tid);
+ ieee80211_agg_splice_packets(local, sta->ampdu_mlme.tid_tx[tid], tid);
/*
- * NB: we rely on sta->lock being taken in the TX
- * processing here when adding to the pending queue,
- * otherwise we could only change the state of the
- * session to OPERATIONAL _here_.
+ * Now mark as operational. This will be visible
+ * in the TX path, and lets it go lock-free in
+ * the common case.
*/
- ieee80211_agg_splice_finish(local, sta, tid);
+ set_bit(HT_AGG_STATE_OPERATIONAL, &sta->ampdu_mlme.tid_tx[tid]->state);
+ ieee80211_agg_splice_finish(local, tid);
spin_unlock(&local->ampdu_lock);
drv_ampdu_action(local, sta->sdata,
@@ -434,7 +435,7 @@ void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
- u8 *state;
+ struct tid_ampdu_tx *tid_tx;
trace_api_start_tx_ba_cb(sdata, ra, tid);
@@ -456,25 +457,22 @@ void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
return;
}
- state = &sta->ampdu_mlme.tid_state_tx[tid];
spin_lock_bh(&sta->lock);
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
- if (WARN_ON(!(*state & HT_ADDBA_REQUESTED_MSK))) {
+ if (WARN_ON(!tid_tx)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
- printk(KERN_DEBUG "addBA was not requested yet, state is %d\n",
- *state);
+ printk(KERN_DEBUG "addBA was not requested!\n");
#endif
spin_unlock_bh(&sta->lock);
rcu_read_unlock();
return;
}
- if (WARN_ON(*state & HT_ADDBA_DRV_READY_MSK))
+ if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
goto out;
- *state |= HT_ADDBA_DRV_READY_MSK;
-
- if (*state == HT_AGG_STATE_OPERATIONAL)
+ if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
ieee80211_agg_tx_operational(local, sta, tid);
out:
@@ -512,14 +510,14 @@ EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
enum ieee80211_back_parties initiator)
{
- u8 *state;
+ struct tid_ampdu_tx *tid_tx;
int ret;
- /* check if the TID is in aggregation */
- state = &sta->ampdu_mlme.tid_state_tx[tid];
spin_lock_bh(&sta->lock);
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
- if (*state != HT_AGG_STATE_OPERATIONAL) {
+ /* check if the TID is in aggregation */
+ if (!tid_tx || !test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
ret = -ENOENT;
goto unlock;
}
@@ -554,7 +552,7 @@ void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
- u8 *state;
+ struct tid_ampdu_tx *tid_tx;
trace_api_stop_tx_ba_cb(sdata, ra, tid);
@@ -580,39 +578,45 @@ void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
rcu_read_unlock();
return;
}
- state = &sta->ampdu_mlme.tid_state_tx[tid];
- /* NOTE: no need to use sta->lock in this state check, as
- * ieee80211_stop_tx_ba_session will let only one stop call to
- * pass through per sta/tid
- */
- if ((*state & HT_AGG_STATE_REQ_STOP_BA_MSK) == 0) {
+ spin_lock_bh(&sta->lock);
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
+
+ if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
#endif
+ spin_unlock_bh(&sta->lock);
rcu_read_unlock();
return;
}
- if (*state & HT_AGG_STATE_INITIATOR_MSK)
+ if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR)
ieee80211_send_delba(sta->sdata, ra, tid,
WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
- spin_lock_bh(&sta->lock);
- spin_lock(&local->ampdu_lock);
+ /*
+ * When we get here, the TX path will not be lockless any more wrt.
+ * aggregation, since the OPERATIONAL bit has long been cleared.
+ * Thus it will block on getting the lock, if it occurs. So if we
+ * stop the queue now, we will not get any more packets, and any
+ * that might be being processed will wait for us here, thereby
+ * guaranteeing that no packets go to the tid_tx pending queue any
+ * more.
+ */
- ieee80211_agg_splice_packets(local, sta, tid);
+ spin_lock(&local->ampdu_lock);
+ ieee80211_agg_splice_packets(local, tid_tx, tid);
- *state = HT_AGG_STATE_IDLE;
- /* from now on packets are no longer put onto sta->pending */
- kfree(sta->ampdu_mlme.tid_tx[tid]);
- sta->ampdu_mlme.tid_tx[tid] = NULL;
+ /* future packets must not find the tid_tx struct any more */
+ rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], NULL);
- ieee80211_agg_splice_finish(local, sta, tid);
+ ieee80211_agg_splice_finish(local, tid);
+ call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
spin_unlock(&local->ampdu_lock);
- spin_unlock_bh(&sta->lock);
+ spin_unlock_bh(&sta->lock);
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb);
@@ -649,40 +653,41 @@ void ieee80211_process_addba_resp(struct ieee80211_local *local,
struct ieee80211_mgmt *mgmt,
size_t len)
{
+ struct tid_ampdu_tx *tid_tx;
u16 capab, tid;
- u8 *state;
capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
- state = &sta->ampdu_mlme.tid_state_tx[tid];
-
spin_lock_bh(&sta->lock);
- if (!(*state & HT_ADDBA_REQUESTED_MSK))
+ tid_tx = sta->ampdu_mlme.tid_tx[tid];
+
+ if (!tid_tx)
goto out;
- if (mgmt->u.action.u.addba_resp.dialog_token !=
- sta->ampdu_mlme.tid_tx[tid]->dialog_token) {
+ if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
-#endif /* CONFIG_MAC80211_HT_DEBUG */
+#endif
goto out;
}
- del_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
+ del_timer(&tid_tx->addba_resp_timer);
#ifdef CONFIG_MAC80211_HT_DEBUG
printk(KERN_DEBUG "switched off addBA timer for tid %d\n", tid);
-#endif /* CONFIG_MAC80211_HT_DEBUG */
+#endif
if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
== WLAN_STATUS_SUCCESS) {
- u8 curstate = *state;
-
- *state |= HT_ADDBA_RECEIVED_MSK;
+ if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
+ &tid_tx->state)) {
+ /* ignore duplicate response */
+ goto out;
+ }
- if (*state != curstate && *state == HT_AGG_STATE_OPERATIONAL)
+ 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;
diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c
index 95c1ea4..8a74ffb 100644
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -134,15 +134,15 @@ static ssize_t sta_agg_status_read(struct file *file, char __user *userbuf,
sta->ampdu_mlme.tid_rx[i]->ssn : 0);
p += scnprintf(p, sizeof(buf) + buf - p, "\t\t%x",
- sta->ampdu_mlme.tid_state_tx[i]);
+ !!sta->ampdu_mlme.tid_tx[i]);
p += scnprintf(p, sizeof(buf) + buf - p, "\t%#.2x",
- sta->ampdu_mlme.tid_state_tx[i] ?
+ 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_state_tx[i] ?
+ 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_state_tx[i] ?
+ sta->ampdu_mlme.tid_tx[i] ?
skb_queue_len(&sta->ampdu_mlme.tid_tx[i]->pending) : 0);
p += scnprintf(p, sizeof(buf) + buf - p, "\n");
}
diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index 2ab106a..1af173e 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -176,13 +176,8 @@ void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
if (initiator == WLAN_BACK_INITIATOR)
__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0);
- else { /* WLAN_BACK_RECIPIENT */
- spin_lock_bh(&sta->lock);
- if (sta->ampdu_mlme.tid_state_tx[tid] & HT_ADDBA_REQUESTED_MSK)
- ___ieee80211_stop_tx_ba_session(sta, tid,
- WLAN_BACK_RECIPIENT);
- spin_unlock_bh(&sta->lock);
- }
+ else
+ __ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT);
}
int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index bafe610..71bdd8b 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1119,8 +1119,6 @@ void ieee80211_process_addba_request(struct ieee80211_local *local,
int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
enum ieee80211_back_parties initiator);
-int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
- enum ieee80211_back_parties initiator);
/* Spectrum management */
void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
index c23f082..7a04951 100644
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -365,7 +365,7 @@ minstrel_aggr_check(struct minstrel_priv *mp, struct ieee80211_sta *pubsta, stru
return;
tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
- if (likely(sta->ampdu_mlme.tid_state_tx[tid] != HT_AGG_STATE_IDLE))
+ if (likely(sta->ampdu_mlme.tid_tx[tid]))
return;
ieee80211_start_tx_ba_session(pubsta, tid);
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index c426c57..06d8e00 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -246,14 +246,12 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
}
for (i = 0; i < STA_TID_NUM; i++) {
- /* timer_to_tid must be initialized with identity mapping to
- * enable session_timer's data differentiation. refer to
- * sta_rx_agg_session_timer_expired for useage */
+ /*
+ * timer_to_tid must be initialized with identity mapping
+ * to enable session_timer's data differentiation. See
+ * sta_rx_agg_session_timer_expired for usage.
+ */
sta->timer_to_tid[i] = i;
- /* tx */
- sta->ampdu_mlme.tid_state_tx[i] = HT_AGG_STATE_IDLE;
- sta->ampdu_mlme.tid_tx[i] = NULL;
- sta->ampdu_mlme.addba_req_num[i] = 0;
}
skb_queue_head_init(&sta->ps_tx_buf);
skb_queue_head_init(&sta->tx_filtered);
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 16864a6..05278e6 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -61,33 +61,40 @@ enum ieee80211_sta_info_flags {
#define STA_TID_NUM 16
#define ADDBA_RESP_INTERVAL HZ
-#define HT_AGG_MAX_RETRIES (0x3)
+#define HT_AGG_MAX_RETRIES 0x3
-#define HT_AGG_STATE_INITIATOR_SHIFT (4)
-
-#define HT_ADDBA_REQUESTED_MSK BIT(0)
-#define HT_ADDBA_DRV_READY_MSK BIT(1)
-#define HT_ADDBA_RECEIVED_MSK BIT(2)
-#define HT_AGG_STATE_REQ_STOP_BA_MSK BIT(3)
-#define HT_AGG_STATE_INITIATOR_MSK BIT(HT_AGG_STATE_INITIATOR_SHIFT)
-#define HT_AGG_STATE_IDLE (0x0)
-#define HT_AGG_STATE_OPERATIONAL (HT_ADDBA_REQUESTED_MSK | \
- HT_ADDBA_DRV_READY_MSK | \
- HT_ADDBA_RECEIVED_MSK)
+#define HT_AGG_STATE_DRV_READY 0
+#define HT_AGG_STATE_RESPONSE_RECEIVED 1
+#define HT_AGG_STATE_OPERATIONAL 2
+#define HT_AGG_STATE_STOPPING 3
/**
* struct tid_ampdu_tx - TID aggregation information (Tx).
*
+ * @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
+ *
+ * This structure is protected by RCU and the per-station
+ * spinlock. Assignments to the array holding it must hold
+ * the spinlock, only the TX path can access it under RCU
+ * lock-free if, and only if, the state has the flag
+ * %HT_AGG_STATE_OPERATIONAL set. Otherwise, the TX path
+ * must also acquire the spinlock and re-check the state,
+ * see comments in the tx code touching it.
*/
struct tid_ampdu_tx {
+ struct rcu_head rcu_head;
struct timer_list addba_resp_timer;
struct sk_buff_head pending;
+ unsigned long state;
u16 ssn;
u8 dialog_token;
+ u8 stop_initiator;
};
/**
@@ -129,7 +136,6 @@ struct tid_ampdu_rx {
* struct sta_ampdu_mlme - STA aggregation information.
*
* @tid_rx: aggregation info for Rx per TID -- RCU protected
- * @tid_state_tx: TID's state in Tx session state machine.
* @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;
@@ -138,7 +144,6 @@ struct sta_ampdu_mlme {
/* rx */
struct tid_ampdu_rx *tid_rx[STA_TID_NUM];
/* tx */
- u8 tid_state_tx[STA_TID_NUM];
struct tid_ampdu_tx *tid_tx[STA_TID_NUM];
u8 addba_req_num[STA_TID_NUM];
u8 dialog_token_allocator;
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 680bcb7..7bf1f9c 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1092,6 +1092,54 @@ static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
return true;
}
+static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
+ struct sk_buff *skb,
+ struct ieee80211_tx_info *info,
+ struct tid_ampdu_tx *tid_tx,
+ int tid)
+{
+ bool queued = false;
+
+ if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
+ info->flags |= IEEE80211_TX_CTL_AMPDU;
+ } else {
+ spin_lock(&tx->sta->lock);
+ /*
+ * Need to re-check now, because we may get here
+ *
+ * 1) in the window during which the setup is actually
+ * already done, but not marked yet because not all
+ * packets are spliced over to the driver pending
+ * queue yet -- if this happened we acquire the lock
+ * either before or after the splice happens, but
+ * need to recheck which of these cases happened.
+ *
+ * 2) during session teardown, if the OPERATIONAL bit
+ * was cleared due to the teardown but the pointer
+ * hasn't been assigned NULL yet (or we loaded it
+ * before it was assigned) -- in this case it may
+ * now be NULL which means we should just let the
+ * packet pass through because splicing the frames
+ * back is already done.
+ */
+ tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
+
+ if (!tid_tx) {
+ /* do nothing, let packet pass through */
+ } else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
+ info->flags |= IEEE80211_TX_CTL_AMPDU;
+ } else {
+ queued = true;
+ info->control.vif = &tx->sdata->vif;
+ info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+ __skb_queue_tail(&tid_tx->pending, skb);
+ }
+ spin_unlock(&tx->sta->lock);
+ }
+
+ return queued;
+}
+
/*
* initialises @tx
*/
@@ -1104,8 +1152,7 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
struct ieee80211_hdr *hdr;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
int hdrlen, tid;
- u8 *qc, *state;
- bool queued = false;
+ u8 *qc;
memset(tx, 0, sizeof(*tx));
tx->skb = skb;
@@ -1157,35 +1204,16 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
qc = ieee80211_get_qos_ctl(hdr);
tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
- spin_lock(&tx->sta->lock);
- /*
- * XXX: This spinlock could be fairly expensive, but see the
- * comment in agg-tx.c:ieee80211_agg_tx_operational().
- * One way to solve this would be to do something RCU-like
- * for managing the tid_tx struct and using atomic bitops
- * for the actual state -- by introducing an actual
- * 'operational' bit that would be possible. It would
- * require changing ieee80211_agg_tx_operational() to
- * set that bit, and changing the way tid_tx is managed
- * everywhere, including races between that bit and
- * tid_tx going away (tid_tx being added can be easily
- * committed to memory before the 'operational' bit).
- */
- tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
- state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
- if (*state == HT_AGG_STATE_OPERATIONAL) {
- info->flags |= IEEE80211_TX_CTL_AMPDU;
- } else if (*state != HT_AGG_STATE_IDLE) {
- /* in progress */
- queued = true;
- info->control.vif = &sdata->vif;
- info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
- __skb_queue_tail(&tid_tx->pending, skb);
- }
- spin_unlock(&tx->sta->lock);
+ tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
+ if (tid_tx) {
+ bool queued;
- if (unlikely(queued))
- return TX_QUEUED;
+ queued = ieee80211_tx_prep_agg(tx, skb, info,
+ tid_tx, tid);
+
+ if (unlikely(queued))
+ return TX_QUEUED;
+ }
}
if (is_multicast_ether_addr(hdr->addr1)) {