[RFC 0/6] some mac80211 aggregation work

[RFC 0/6] some mac80211 aggregation work

[Johannes Berg]

This is untested, wanted to see what people think :-)

The basic reason for this is that we currently ask for
aggregation stop but there's no clear indication of what
should actually happen, if the frames should be dropped
or maybe not etc., so I'm changing that.

johannes

[RFC 1/6] mac80211: don't send delBA before disassoc

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

When we disassociate, it's not really useful to
send delBA action frames since we're going to send
disassoc/deauth anyway, so change that.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/mlme.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index b7975be..42b2a06 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1363,7 +1363,7 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 	sta = sta_info_get(sdata, bssid);
 	if (sta) {
 		set_sta_flag(sta, WLAN_STA_BLOCK_BA);
-		ieee80211_sta_tear_down_BA_sessions(sta, tx);
+		ieee80211_sta_tear_down_BA_sessions(sta, false);
 	}
 	mutex_unlock(&local->sta_mtx);
 
-- 
1.7.10.4

[RFC 2/6] mac80211: don't send delBA when removing stations

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

When a station is removed and we stop the aggregation
sessions, it's not useful to send delBA since this is
due to us or the station disassociating or dropping
the connection in some other way, so change that.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/sta_info.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 06fa75c..97d82f4 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -674,7 +674,7 @@ int __must_check __sta_info_destroy(struct sta_info *sta)
 	 * will be sufficient.
 	 */
 	set_sta_flag(sta, WLAN_STA_BLOCK_BA);
-	ieee80211_sta_tear_down_BA_sessions(sta, true);
+	ieee80211_sta_tear_down_BA_sessions(sta, false);
 
 	ret = sta_info_hash_del(local, sta);
 	if (ret)
-- 
1.7.10.4

[RFC 3/6] mac80211: don't send delBA on addBA failure

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

There's no reason to send a delBA when the
peer refused our addBA, so change that.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/agg-tx.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index d0deb3e..3195a63 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -869,7 +869,7 @@ void ieee80211_process_addba_resp(struct ieee80211_local *local,
 
 	} else {
 		___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
-						true);
+						false);
 	}
 
  out:
-- 
1.7.10.4

[RFC 4/6] mac80211: split aggregation stop by reason

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

The initiator/tx doesn't really identify why an
aggregation session is stopped, give a reason
for stopping that more clearly identifies what's
going on. This will help tell the driver clearly
what is expected of it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/agg-tx.c      |   17 ++++++++---------
 net/mac80211/ht.c          |   15 ++++++++-------
 net/mac80211/ieee80211_i.h |    9 ++++-----
 net/mac80211/mlme.c        |    2 +-
 net/mac80211/pm.c          |    3 ++-
 net/mac80211/sta_info.c    |    2 +-
 net/mac80211/sta_info.h    |    7 +++++++
 net/mac80211/util.c        |    3 ++-
 8 files changed, 33 insertions(+), 25 deletions(-)

diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 3195a63..34d318e 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -150,8 +150,7 @@ void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
 }
 
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				    enum ieee80211_back_parties initiator,
-				    bool tx)
+				    enum ieee80211_agg_stop_reason reason)
 {
 	struct ieee80211_local *local = sta->local;
 	struct tid_ampdu_tx *tid_tx;
@@ -212,8 +211,10 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 	 */
 	synchronize_net();
 
-	tid_tx->stop_initiator = initiator;
-	tid_tx->tx_stop = tx;
+	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,
 			       IEEE80211_AMPDU_TX_STOP,
@@ -660,14 +661,13 @@ void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
 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,
-				   bool tx)
+				   enum ieee80211_agg_stop_reason reason)
 {
 	int ret;
 
 	mutex_lock(&sta->ampdu_mlme.mtx);
 
-	ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
+	ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason);
 
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 
@@ -868,8 +868,7 @@ void ieee80211_process_addba_resp(struct ieee80211_local *local,
 		}
 
 	} else {
-		___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
-						false);
+		___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
 	}
 
  out:
diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index 4b4538d..8fda036 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -179,16 +179,19 @@ void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
 	ieee80211_apply_htcap_overrides(sdata, ht_cap);
 }
 
-void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx)
+void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
+					 enum ieee80211_agg_stop_reason reason)
 {
 	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, tx);
+		__ieee80211_stop_tx_ba_session(sta, i, reason);
 		__ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
-					       WLAN_REASON_QSTA_LEAVE_QBSS, tx);
+					       WLAN_REASON_QSTA_LEAVE_QBSS,
+					       reason != AGG_STOP_DESTROY_STA &&
+					       reason != AGG_STOP_PEER_REQUEST);
 	}
 }
 
@@ -245,8 +248,7 @@ void ieee80211_ba_session_work(struct work_struct *work)
 		if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 						 &tid_tx->state))
 			___ieee80211_stop_tx_ba_session(sta, tid,
-							WLAN_BACK_INITIATOR,
-							true);
+							AGG_STOP_LOCAL_REQUEST);
 	}
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 }
@@ -314,8 +316,7 @@ void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
 					       true);
 	else
-		__ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
-					       true);
+		__ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
 }
 
 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 2ba0af4..83c6d75 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1328,7 +1328,8 @@ void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
 				     u16 initiator, u16 reason, bool stop);
 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
 				    u16 initiator, u16 reason, bool stop);
-void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx);
+void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
+					 enum ieee80211_agg_stop_reason reason);
 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 			     struct sta_info *sta,
 			     struct ieee80211_mgmt *mgmt, size_t len);
@@ -1342,11 +1343,9 @@ void ieee80211_process_addba_request(struct ieee80211_local *local,
 				     size_t len);
 
 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				   enum ieee80211_back_parties initiator,
-				   bool tx);
+				   enum ieee80211_agg_stop_reason reason);
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				    enum ieee80211_back_parties initiator,
-				    bool tx);
+				    enum ieee80211_agg_stop_reason reason);
 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_ba_session_work(struct work_struct *work);
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 42b2a06..af1c5c3 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1363,7 +1363,7 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 	sta = sta_info_get(sdata, bssid);
 	if (sta) {
 		set_sta_flag(sta, WLAN_STA_BLOCK_BA);
-		ieee80211_sta_tear_down_BA_sessions(sta, false);
+		ieee80211_sta_tear_down_BA_sessions(sta, AGG_STOP_DESTROY_STA);
 	}
 	mutex_unlock(&local->sta_mtx);
 
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index 5c572e7..6a155dc 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -43,7 +43,8 @@ int __ieee80211_suspend(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan)
 		mutex_lock(&local->sta_mtx);
 		list_for_each_entry(sta, &local->sta_list, list) {
 			set_sta_flag(sta, WLAN_STA_BLOCK_BA);
-			ieee80211_sta_tear_down_BA_sessions(sta, true);
+			ieee80211_sta_tear_down_BA_sessions(
+					sta, AGG_STOP_LOCAL_REQUEST);
 		}
 		mutex_unlock(&local->sta_mtx);
 	}
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 97d82f4..7fdd663 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -674,7 +674,7 @@ int __must_check __sta_info_destroy(struct sta_info *sta)
 	 * will be sufficient.
 	 */
 	set_sta_flag(sta, WLAN_STA_BLOCK_BA);
-	ieee80211_sta_tear_down_BA_sessions(sta, false);
+	ieee80211_sta_tear_down_BA_sessions(sta, AGG_STOP_DESTROY_STA);
 
 	ret = sta_info_hash_del(local, sta);
 	if (ret)
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index a470e11..a62c241 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -93,6 +93,13 @@ enum ieee80211_sta_info_flags {
 #define HT_AGG_STATE_WANT_START		4
 #define HT_AGG_STATE_WANT_STOP		5
 
+enum ieee80211_agg_stop_reason {
+	AGG_STOP_DECLINED,
+	AGG_STOP_LOCAL_REQUEST,
+	AGG_STOP_PEER_REQUEST,
+	AGG_STOP_DESTROY_STA,
+};
+
 /**
  * struct tid_ampdu_tx - TID aggregation information (Tx).
  *
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 9fbc431..d4f4a9f 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1462,7 +1462,8 @@ int ieee80211_reconfig(struct ieee80211_local *local)
 		mutex_lock(&local->sta_mtx);
 
 		list_for_each_entry(sta, &local->sta_list, list) {
-			ieee80211_sta_tear_down_BA_sessions(sta, true);
+			ieee80211_sta_tear_down_BA_sessions(
+					sta, AGG_STOP_LOCAL_REQUEST);
 			clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
 		}
 
-- 
1.7.10.4

[RFC 5/6] mac80211: split out aggregation TX removal

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

Create the function ieee80211_remove_tid_tx to call
it from ___ieee80211_stop_tx_ba_session in the next
patch, it's also necessary to move the code up in
the file for this.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/agg-tx.c |  196 ++++++++++++++++++++++++++-----------------------
 1 file changed, 104 insertions(+), 92 deletions(-)

diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 34d318e..5359b5c 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -149,6 +149,109 @@ void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
 	rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
 }
 
+static inline int ieee80211_ac_from_tid(int tid)
+{
+	return ieee802_1d_to_ac[tid & 7];
+}
+
+/*
+ * When multiple aggregation sessions on multiple stations
+ * are being created/destroyed simultaneously, we need to
+ * refcount the global queue stop caused by that in order
+ * to not get into a situation where one of the aggregation
+ * setup or teardown re-enables queues before the other is
+ * ready to handle that.
+ *
+ * These two functions take care of this issue by keeping
+ * a global "agg_queue_stop" refcount.
+ */
+static void __acquires(agg_queue)
+ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
+{
+	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
+
+	if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
+		ieee80211_stop_queue_by_reason(
+			&sdata->local->hw, queue,
+			IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+	__acquire(agg_queue);
+}
+
+static void __releases(agg_queue)
+ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
+{
+	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
+
+	if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
+		ieee80211_wake_queue_by_reason(
+			&sdata->local->hw, queue,
+			IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+	__release(agg_queue);
+}
+
+/*
+ * splice packets from the STA's pending to the local pending,
+ * requires a call to ieee80211_agg_splice_finish later
+ */
+static void __acquires(agg_queue)
+ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata,
+			     struct tid_ampdu_tx *tid_tx, u16 tid)
+{
+	struct ieee80211_local *local = sdata->local;
+	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
+	unsigned long flags;
+
+	ieee80211_stop_queue_agg(sdata, tid);
+
+	if (WARN(!tid_tx,
+		 "TID %d gone but expected when splicing aggregates from the pending queue\n",
+		 tid))
+		return;
+
+	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(&tid_tx->pending,
+					   &local->pending[queue]);
+		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+	}
+}
+
+static void __releases(agg_queue)
+ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
+{
+	ieee80211_wake_queue_agg(sdata, tid);
+}
+
+static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid)
+{
+	struct tid_ampdu_tx *tid_tx;
+
+	lockdep_assert_held(&sta->ampdu_mlme.mtx);
+	lockdep_assert_held(&sta->lock);
+
+	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
+
+	/*
+	 * 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(sta->sdata, tid_tx, tid);
+
+	/* future packets must not find the tid_tx struct any more */
+	ieee80211_assign_tid_tx(sta, tid, NULL);
+
+	ieee80211_agg_splice_finish(sta->sdata, tid);
+
+	kfree_rcu(tid_tx, rcu_head);
+}
+
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 				    enum ieee80211_agg_stop_reason reason)
 {
@@ -265,80 +368,6 @@ static void sta_addba_resp_timer_expired(unsigned long data)
 	rcu_read_unlock();
 }
 
-static inline int ieee80211_ac_from_tid(int tid)
-{
-	return ieee802_1d_to_ac[tid & 7];
-}
-
-/*
- * When multiple aggregation sessions on multiple stations
- * are being created/destroyed simultaneously, we need to
- * refcount the global queue stop caused by that in order
- * to not get into a situation where one of the aggregation
- * setup or teardown re-enables queues before the other is
- * ready to handle that.
- *
- * These two functions take care of this issue by keeping
- * a global "agg_queue_stop" refcount.
- */
-static void __acquires(agg_queue)
-ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
-{
-	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
-
-	if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
-		ieee80211_stop_queue_by_reason(
-			&sdata->local->hw, queue,
-			IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
-	__acquire(agg_queue);
-}
-
-static void __releases(agg_queue)
-ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
-{
-	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
-
-	if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
-		ieee80211_wake_queue_by_reason(
-			&sdata->local->hw, queue,
-			IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
-	__release(agg_queue);
-}
-
-/*
- * splice packets from the STA's pending to the local pending,
- * requires a call to ieee80211_agg_splice_finish later
- */
-static void __acquires(agg_queue)
-ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata,
-			     struct tid_ampdu_tx *tid_tx, u16 tid)
-{
-	struct ieee80211_local *local = sdata->local;
-	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
-	unsigned long flags;
-
-	ieee80211_stop_queue_agg(sdata, tid);
-
-	if (WARN(!tid_tx,
-		 "TID %d gone but expected when splicing aggregates from the pending queue\n",
-		 tid))
-		return;
-
-	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(&tid_tx->pending,
-					   &local->pending[queue]);
-		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
-	}
-}
-
-static void __releases(agg_queue)
-ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
-{
-	ieee80211_wake_queue_agg(sdata, tid);
-}
-
 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 {
 	struct tid_ampdu_tx *tid_tx;
@@ -751,24 +780,7 @@ void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
 		ieee80211_send_delba(sta->sdata, ra, tid,
 			WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
 
-	/*
-	 * 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(sta->sdata, tid_tx, tid);
-
-	/* future packets must not find the tid_tx struct any more */
-	ieee80211_assign_tid_tx(sta, tid, NULL);
-
-	ieee80211_agg_splice_finish(sta->sdata, tid);
-
-	kfree_rcu(tid_tx, rcu_head);
+	ieee80211_remove_tid_tx(sta, tid);
 
  unlock_sta:
 	spin_unlock_bh(&sta->lock);
-- 
1.7.10.4

[RFC 6/6] mac80211: split TX aggregation stop action

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

When TX aggregation is stopped, there are a few
different cases:
 - connection with the peer was dropped
 - session stop was requested locally
 - session stop was requested by the peer
 - connection was dropped while a session is stopping

The behaviour in these cases should be different, if
the connection is dropped then the driver should drop
all frames, otherwise the frames may continue to be
transmitted, aggregated in the case of a locally
requested session stop or unaggregated in the case of
the peer requesting session stop.

Split these different cases so that the driver can
act accordingly; however, treat local and remote stop
the same way and ask the driver to not send frames as
aggregated packets any more.

In the case of connection drop, the stop callback the
driver is otherwise supposed to call is no longer
required.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 drivers/net/wireless/ath/ath9k/htc_drv_main.c      |    4 ++-
 drivers/net/wireless/ath/ath9k/main.c              |    4 ++-
 drivers/net/wireless/ath/carl9170/main.c           |    4 ++-
 .../net/wireless/brcm80211/brcmsmac/mac80211_if.c  |    4 ++-
 drivers/net/wireless/iwlegacy/4965-mac.c           |    4 ++-
 drivers/net/wireless/iwlwifi/dvm/mac80211.c        |    4 ++-
 drivers/net/wireless/mac80211_hwsim.c              |    4 ++-
 drivers/net/wireless/mwl8k.c                       |    4 ++-
 drivers/net/wireless/rt2x00/rt2800lib.c            |    4 ++-
 drivers/net/wireless/rtlwifi/core.c                |    4 ++-
 drivers/net/wireless/ti/wlcore/main.c              |    4 ++-
 include/net/mac80211.h                             |   22 +++++++++---
 net/mac80211/agg-tx.c                              |   38 +++++++++++++++++---
 13 files changed, 83 insertions(+), 21 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_main.c b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
index fc8cd828..ca73d24 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_main.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
@@ -1619,7 +1619,9 @@ static int ath9k_htc_ampdu_action(struct ieee80211_hw *hw,
 		if (!ret)
 			ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		ath9k_htc_tx_aggr_oper(priv, vif, sta, action, tid);
 		ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index e4e73f0..90538e8 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1690,7 +1690,9 @@ static int ath9k_ampdu_action(struct ieee80211_hw *hw,
 			ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		ath9k_ps_restore(sc);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		ath9k_ps_wakeup(sc);
 		ath_tx_aggr_stop(sc, sta, tid);
 		ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c
index 8d2523b..ac27504 100644
--- a/drivers/net/wireless/ath/carl9170/main.c
+++ b/drivers/net/wireless/ath/carl9170/main.c
@@ -1389,7 +1389,9 @@ static int carl9170_op_ampdu_action(struct ieee80211_hw *hw,
 		ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
 
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		rcu_read_lock();
 		tid_info = rcu_dereference(sta_info->agg[tid]);
 		if (tid_info) {
diff --git a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
index 2d5a404..f5ae62e 100644
--- a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
+++ b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
@@ -651,7 +651,9 @@ brcms_ops_ampdu_action(struct ieee80211_hw *hw,
 		ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
 
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		spin_lock_bh(&wl->lock);
 		brcms_c_ampdu_flush(wl->wlc, sta, tid);
 		spin_unlock_bh(&wl->lock);
diff --git a/drivers/net/wireless/iwlegacy/4965-mac.c b/drivers/net/wireless/iwlegacy/4965-mac.c
index d24eaf8..9790364 100644
--- a/drivers/net/wireless/iwlegacy/4965-mac.c
+++ b/drivers/net/wireless/iwlegacy/4965-mac.c
@@ -5964,7 +5964,9 @@ il4965_mac_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 		D_HT("start Tx\n");
 		ret = il4965_tx_agg_start(il, vif, sta, tid, ssn);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		D_HT("stop Tx\n");
 		ret = il4965_tx_agg_stop(il, vif, sta, tid);
 		if (test_bit(S_EXIT_PENDING, &il->status))
diff --git a/drivers/net/wireless/iwlwifi/dvm/mac80211.c b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
index b83ca35..56f42e8 100644
--- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
@@ -674,7 +674,9 @@ static int iwlagn_mac_ampdu_action(struct ieee80211_hw *hw,
 		IWL_DEBUG_HT(priv, "start Tx\n");
 		ret = iwlagn_tx_agg_start(priv, vif, sta, tid, ssn);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		IWL_DEBUG_HT(priv, "stop Tx\n");
 		ret = iwlagn_tx_agg_stop(priv, vif, sta, tid);
 		if ((ret == 0) && (priv->agg_tids_count > 0)) {
diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index d03ee5b..97f87f0 100644
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -1149,7 +1149,9 @@ static int mac80211_hwsim_ampdu_action(struct ieee80211_hw *hw,
 	case IEEE80211_AMPDU_TX_START:
 		ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
 	case IEEE80211_AMPDU_TX_OPERATIONAL:
diff --git a/drivers/net/wireless/mwl8k.c b/drivers/net/wireless/mwl8k.c
index cf7bdc6..8b10854 100644
--- a/drivers/net/wireless/mwl8k.c
+++ b/drivers/net/wireless/mwl8k.c
@@ -5146,7 +5146,9 @@ mwl8k_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 		}
 		ieee80211_start_tx_ba_cb_irqsafe(vif, addr, tid);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		if (stream) {
 			if (stream->state == AMPDU_STREAM_ACTIVE) {
 				spin_unlock(&priv->stream_lock);
diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c
index 068276e..a2f2305 100644
--- a/drivers/net/wireless/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/rt2x00/rt2800lib.c
@@ -5110,7 +5110,9 @@ int rt2800_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 	case IEEE80211_AMPDU_TX_START:
 		ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
 		break;
 	case IEEE80211_AMPDU_TX_OPERATIONAL:
diff --git a/drivers/net/wireless/rtlwifi/core.c b/drivers/net/wireless/rtlwifi/core.c
index 278e9f9..9656c1c 100644
--- a/drivers/net/wireless/rtlwifi/core.c
+++ b/drivers/net/wireless/rtlwifi/core.c
@@ -877,7 +877,9 @@ static int rtl_op_ampdu_action(struct ieee80211_hw *hw,
 			 "IEEE80211_AMPDU_TX_START: TID:%d\n", tid);
 		return rtl_tx_agg_start(hw, sta, tid, ssn);
 		break;
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 		RT_TRACE(rtlpriv, COMP_MAC80211, DBG_TRACE,
 			 "IEEE80211_AMPDU_TX_STOP: TID:%d\n", tid);
 		return rtl_tx_agg_stop(hw, sta, tid);
diff --git a/drivers/net/wireless/ti/wlcore/main.c b/drivers/net/wireless/ti/wlcore/main.c
index 0cc9a02..27e1932 100644
--- a/drivers/net/wireless/ti/wlcore/main.c
+++ b/drivers/net/wireless/ti/wlcore/main.c
@@ -4534,7 +4534,9 @@ static int wl1271_op_ampdu_action(struct ieee80211_hw *hw,
 	 * Falling break here on purpose for all TX APDU commands.
 	 */
 	case IEEE80211_AMPDU_TX_START:
-	case IEEE80211_AMPDU_TX_STOP:
+	case IEEE80211_AMPDU_TX_STOP_CONT:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH:
+	case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
 	case IEEE80211_AMPDU_TX_OPERATIONAL:
 		ret = -EINVAL;
 		break;
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index c609b9d..0fe82e3 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1883,17 +1883,29 @@ enum ieee80211_filter_flags {
  * calling ieee80211_start_tx_ba_cb_irqsafe, because the peer
  * might receive the addBA frame and send a delBA right away!
  *
- * @IEEE80211_AMPDU_RX_START: start Rx aggregation
- * @IEEE80211_AMPDU_RX_STOP: stop Rx aggregation
- * @IEEE80211_AMPDU_TX_START: start Tx aggregation
- * @IEEE80211_AMPDU_TX_STOP: stop Tx aggregation
+ * @IEEE80211_AMPDU_RX_START: start RX aggregation
+ * @IEEE80211_AMPDU_RX_STOP: stop RX aggregation
+ * @IEEE80211_AMPDU_TX_START: start TX aggregation
  * @IEEE80211_AMPDU_TX_OPERATIONAL: TX aggregation has become operational
+ * @IEEE80211_AMPDU_TX_STOP_CONT: stop TX aggregation but continue transmitting
+ *	queued packets, now unaggregated. After all packets are transmitted the
+ *	driver has to call ieee80211_stop_tx_ba_cb_irqsafe().
+ * @IEEE80211_AMPDU_TX_STOP_FLUSH: stop TX aggregation and flush all packets,
+ *	called when the station is removed. There's no need or reason to call
+ *	ieee80211_stop_tx_ba_cb_irqsafe() in this case as mac80211 assumes the
+ *	session is gone and removes the station.
+ * @IEEE80211_AMPDU_TX_STOP_FLUSH_CONT: called when TX aggregation is stopped
+ *	but the driver hasn't called ieee80211_stop_tx_ba_cb_irqsafe() yet and
+ *	now the connection is dropped and the station will be removed. Drivers
+ *	should clean up and drop remaining packets when this is called.
  */
 enum ieee80211_ampdu_mlme_action {
 	IEEE80211_AMPDU_RX_START,
 	IEEE80211_AMPDU_RX_STOP,
 	IEEE80211_AMPDU_TX_START,
-	IEEE80211_AMPDU_TX_STOP,
+	IEEE80211_AMPDU_TX_STOP_CONT,
+	IEEE80211_AMPDU_TX_STOP_FLUSH,
+	IEEE80211_AMPDU_TX_STOP_FLUSH_CONT,
 	IEEE80211_AMPDU_TX_OPERATIONAL,
 };
 
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 5359b5c..74ad47d 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -257,10 +257,25 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 {
 	struct ieee80211_local *local = sta->local;
 	struct tid_ampdu_tx *tid_tx;
+	enum ieee80211_ampdu_mlme_action action;
 	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:
+		action = IEEE80211_AMPDU_TX_STOP_CONT;
+		break;
+	case AGG_STOP_DESTROY_STA:
+		action = IEEE80211_AMPDU_TX_STOP_FLUSH;
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return -EINVAL;
+	}
+
 	spin_lock_bh(&sta->lock);
 
 	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
@@ -269,10 +284,19 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 		return -ENOENT;
 	}
 
-	/* if we're already stopping ignore any new requests to stop */
+	/*
+	 * 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);
-		return -EALREADY;
+		if (reason != AGG_STOP_DESTROY_STA)
+			return -EALREADY;
+		ret = drv_ampdu_action(local, sta->sdata,
+				       IEEE80211_AMPDU_TX_STOP_FLUSH_CONT,
+				       &sta->sta, tid, NULL, 0);
+		WARN_ON_ONCE(ret);
+		goto remove_tid_tx;
 	}
 
 	if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
@@ -319,8 +343,7 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 					WLAN_BACK_INITIATOR;
 	tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
 
-	ret = drv_ampdu_action(local, sta->sdata,
-			       IEEE80211_AMPDU_TX_STOP,
+	ret = drv_ampdu_action(local, sta->sdata, action,
 			       &sta->sta, tid, NULL, 0);
 
 	/* HW shall not deny going back to legacy */
@@ -331,7 +354,12 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 		 */
 	}
 
-	return ret;
+	if (reason == AGG_STOP_DESTROY_STA) {
+ remove_tid_tx:
+		ieee80211_remove_tid_tx(sta, tid);
+ 	}
+
+	return 0;
 }
 
 /*
-- 
1.7.10.4