mac80211: avoid transmitting delBA to old AP

When roaming while we have active BA session,
we can end up transmitting delBA frames to
the old AP while we're already on the new AP's
channel, which can cause warnings.

Simply avoid sending those frames, but still
tear down the internal session state, since
they are not really necessary anyway as we
will implicitly disassociate when sending the
association to the new AP.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index 58eab9e..720b7a8 100644
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -56,7 +56,7 @@
 }
 
 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				     u16 initiator, u16 reason)
+				     u16 initiator, u16 reason, bool tx)
 {
 	struct ieee80211_local *local = sta->local;
 	struct tid_ampdu_rx *tid_rx;
@@ -81,7 +81,7 @@
 				"aggregation for tid %d\n", tid);
 
 	/* check if this is a self generated aggregation halt */
-	if (initiator == WLAN_BACK_RECIPIENT)
+	if (initiator == WLAN_BACK_RECIPIENT && tx)
 		ieee80211_send_delba(sta->sdata, sta->sta.addr,
 				     tid, 0, reason);
 
@@ -92,10 +92,10 @@
 }
 
 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				    u16 initiator, u16 reason)
+				    u16 initiator, u16 reason, bool tx)
 {
 	mutex_lock(&sta->ampdu_mlme.mtx);
-	___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason);
+	___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 }
 
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 8f23401..d4679b2 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -145,7 +145,8 @@
 }
 
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				    enum ieee80211_back_parties initiator)
+				    enum ieee80211_back_parties initiator,
+				    bool tx)
 {
 	struct ieee80211_local *local = sta->local;
 	struct tid_ampdu_tx *tid_tx = sta->ampdu_mlme.tid_tx[tid];
@@ -185,6 +186,7 @@
 	clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
 
 	tid_tx->stop_initiator = initiator;
+	tid_tx->tx_stop = tx;
 
 	ret = drv_ampdu_action(local, sta->sdata,
 			       IEEE80211_AMPDU_TX_STOP,
@@ -577,13 +579,14 @@
 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)
+				   enum ieee80211_back_parties initiator,
+				   bool tx)
 {
 	int ret;
 
 	mutex_lock(&sta->ampdu_mlme.mtx);
 
-	ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator);
+	ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
 
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 
@@ -672,7 +675,7 @@
 		goto unlock_sta;
 	}
 
-	if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR)
+	if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
 		ieee80211_send_delba(sta->sdata, ra, tid,
 			WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
 
@@ -772,7 +775,8 @@
 
 		sta->ampdu_mlme.addba_req_num[tid] = 0;
 	} else {
-		___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
+		___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
+						true);
 	}
 
  out:
diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c
index 6b7ff9f..50c40ea 100644
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -196,7 +196,8 @@
 		else
 			ret = ieee80211_stop_tx_ba_session(&sta->sta, tid);
 	} else {
-		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 3);
+		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
+					       3, true);
 		ret = 0;
 	}
 
diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index 11f74f5..4214bb6 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -101,16 +101,16 @@
 		ht_cap->mcs.rx_mask[32/8] |= 1;
 }
 
-void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta)
+void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx)
 {
 	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_tx_ba_session(sta, i, WLAN_BACK_INITIATOR, tx);
 		__ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
-					       WLAN_REASON_QSTA_LEAVE_QBSS);
+					       WLAN_REASON_QSTA_LEAVE_QBSS, tx);
 	}
 }
 
@@ -135,7 +135,7 @@
 		if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 			___ieee80211_stop_rx_ba_session(
 				sta, tid, WLAN_BACK_RECIPIENT,
-				WLAN_REASON_QSTA_TIMEOUT);
+				WLAN_REASON_QSTA_TIMEOUT, true);
 
 		tid_tx = sta->ampdu_mlme.tid_tx[tid];
 		if (!tid_tx)
@@ -146,7 +146,8 @@
 		else if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 					    &tid_tx->state))
 			___ieee80211_stop_tx_ba_session(sta, tid,
-							WLAN_BACK_INITIATOR);
+							WLAN_BACK_INITIATOR,
+							true);
 	}
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 }
@@ -214,9 +215,11 @@
 #endif /* CONFIG_MAC80211_HT_DEBUG */
 
 	if (initiator == WLAN_BACK_INITIATOR)
-		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0);
+		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
+					       true);
 	else
-		__ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT);
+		__ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
+					       true);
 }
 
 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 08509e2..76c2b50 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1175,10 +1175,10 @@
 void ieee80211_request_smps_work(struct work_struct *work);
 
 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				     u16 initiator, u16 reason);
+				     u16 initiator, u16 reason, bool stop);
 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				    u16 initiator, u16 reason);
-void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta);
+				    u16 initiator, u16 reason, bool stop);
+void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx);
 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 			     struct sta_info *sta,
 			     struct ieee80211_mgmt *mgmt, size_t len);
@@ -1192,9 +1192,11 @@
 				     size_t len);
 
 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				   enum ieee80211_back_parties initiator);
+				   enum ieee80211_back_parties initiator,
+				   bool tx);
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				    enum ieee80211_back_parties initiator);
+				    enum ieee80211_back_parties initiator,
+				    bool tx);
 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/iface.c b/net/mac80211/iface.c
index 438a2f5..e99d1b6 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -796,7 +796,8 @@
 
 				__ieee80211_stop_rx_ba_session(
 					sta, tid, WLAN_BACK_RECIPIENT,
-					WLAN_REASON_QSTA_REQUIRE_SETUP);
+					WLAN_REASON_QSTA_REQUIRE_SETUP,
+					true);
 			}
 			mutex_unlock(&local->sta_mtx);
 		} else switch (sdata->vif.type) {
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index cd13aa8..5695c94 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -921,7 +921,7 @@
 }
 
 static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
-				   bool remove_sta)
+				   bool remove_sta, bool tx)
 {
 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 	struct ieee80211_local *local = sdata->local;
@@ -960,7 +960,7 @@
 	sta = sta_info_get(sdata, bssid);
 	if (sta) {
 		set_sta_flags(sta, WLAN_STA_BLOCK_BA);
-		ieee80211_sta_tear_down_BA_sessions(sta);
+		ieee80211_sta_tear_down_BA_sessions(sta, tx);
 	}
 	mutex_unlock(&local->sta_mtx);
 
@@ -1124,7 +1124,7 @@
 
 	printk(KERN_DEBUG "Connection to AP %pM lost.\n", bssid);
 
-	ieee80211_set_disassoc(sdata, true);
+	ieee80211_set_disassoc(sdata, true, true);
 	mutex_unlock(&ifmgd->mtx);
 
 	mutex_lock(&local->mtx);
@@ -1197,7 +1197,7 @@
 	printk(KERN_DEBUG "%s: deauthenticated from %pM (Reason: %u)\n",
 			sdata->name, bssid, reason_code);
 
-	ieee80211_set_disassoc(sdata, true);
+	ieee80211_set_disassoc(sdata, true, false);
 	mutex_lock(&sdata->local->mtx);
 	ieee80211_recalc_idle(sdata->local);
 	mutex_unlock(&sdata->local->mtx);
@@ -1229,7 +1229,7 @@
 	printk(KERN_DEBUG "%s: disassociated from %pM (Reason: %u)\n",
 			sdata->name, mgmt->sa, reason_code);
 
-	ieee80211_set_disassoc(sdata, true);
+	ieee80211_set_disassoc(sdata, true, false);
 	mutex_lock(&sdata->local->mtx);
 	ieee80211_recalc_idle(sdata->local);
 	mutex_unlock(&sdata->local->mtx);
@@ -1880,7 +1880,7 @@
 			printk(KERN_DEBUG "No probe response from AP %pM"
 				" after %dms, disconnecting.\n",
 				bssid, (1000 * IEEE80211_PROBE_WAIT)/HZ);
-			ieee80211_set_disassoc(sdata, true);
+			ieee80211_set_disassoc(sdata, true, true);
 			mutex_unlock(&ifmgd->mtx);
 			mutex_lock(&local->mtx);
 			ieee80211_recalc_idle(local);
@@ -2204,7 +2204,7 @@
 		}
 
 		/* Trying to reassociate - clear previous association state */
-		ieee80211_set_disassoc(sdata, true);
+		ieee80211_set_disassoc(sdata, true, false);
 	}
 	mutex_unlock(&ifmgd->mtx);
 
@@ -2318,7 +2318,7 @@
 
 	memcpy(bssid, req->bss->bssid, ETH_ALEN);
 	if (ifmgd->associated == req->bss) {
-		ieee80211_set_disassoc(sdata, false);
+		ieee80211_set_disassoc(sdata, false, true);
 		mutex_unlock(&ifmgd->mtx);
 		assoc_bss = true;
 	} else {
@@ -2401,7 +2401,7 @@
 	       sdata->name, req->bss->bssid, req->reason_code);
 
 	memcpy(bssid, req->bss->bssid, ETH_ALEN);
-	ieee80211_set_disassoc(sdata, false);
+	ieee80211_set_disassoc(sdata, false, true);
 
 	mutex_unlock(&ifmgd->mtx);
 
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index ce671df..e3e2bce3 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -46,7 +46,7 @@
 	list_for_each_entry(sta, &local->sta_list, list) {
 		if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
 			set_sta_flags(sta, WLAN_STA_BLOCK_BA);
-			ieee80211_sta_tear_down_BA_sessions(sta);
+			ieee80211_sta_tear_down_BA_sessions(sta, true);
 		}
 
 		if (sta->uploaded) {
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index ca2cba9..aeaf2d6 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -633,7 +633,7 @@
 	 * will be sufficient.
 	 */
 	set_sta_flags(sta, WLAN_STA_BLOCK_BA);
-	ieee80211_sta_tear_down_BA_sessions(sta);
+	ieee80211_sta_tear_down_BA_sessions(sta, true);
 
 	spin_lock_irqsave(&local->sta_lock, flags);
 	ret = sta_info_hash_del(local, sta);
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 810c5ce..cf21a2e 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -79,6 +79,7 @@
  * @dialog_token: dialog token for aggregation session
  * @state: session state (see above)
  * @stop_initiator: initiator of a session stop
+ * @tx_stop: TX DelBA frame when stopping
  *
  * This structure is protected by RCU and the per-station
  * spinlock. Assignments to the array holding it must hold
@@ -95,6 +96,7 @@
 	unsigned long state;
 	u8 dialog_token;
 	u8 stop_initiator;
+	bool tx_stop;
 };
 
 /**
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 4ee8f2b..0b6fc92 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1221,7 +1221,7 @@
 		mutex_lock(&local->sta_mtx);
 
 		list_for_each_entry(sta, &local->sta_list, list) {
-			ieee80211_sta_tear_down_BA_sessions(sta);
+			ieee80211_sta_tear_down_BA_sessions(sta, true);
 			clear_sta_flags(sta, WLAN_STA_BLOCK_BA);
 		}