mac80211: split out aggregation TX removal

Create the function ieee80211_remove_tid_tx to call
it from ___ieee80211_stop_tx_ba_session later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/agg-tx.c

@@ -713,6 +713,35 @@ int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
 }
 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
 
+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);
+}
+
 void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
 {
 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
@@ -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);