Commit 2a6cef51 authored by Christian Lamparter's avatar Christian Lamparter Committed by John W. Linville
Browse files

carl9170: stop stale uplink BA sessions 



This patch fixes a possible lengthy stall if the device
is operating as an experimental 11n AP and an STA
[during heavy txrx action] suddenly signalized to go
off-channel (old NetworkManager), or (sleep - which is
unlikely, because then it wouldn't be *active* at all!?).

Because the driver has to manage the BA Window, the
sudden PSM transition can leave active uplink BA
sessions to the STA in a bad state and a proper
cleanup is needed.

Signed-off-by: default avatarChristian Lamparter <chunkeey@googlemail.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent e4a668c5

drivers/net/wireless/ath/carl9170/tx.c

+54 −0
Original line number Diff line number Diff line
@@ -524,6 +524,59 @@ next: 
	}

}



static void carl9170_tx_ampdu_timeout(struct ar9170 *ar)

{

	struct carl9170_sta_tid *iter;

	struct sk_buff *skb;

	struct ieee80211_tx_info *txinfo;

	struct carl9170_tx_info *arinfo;

	struct _carl9170_tx_superframe *super;

	struct ieee80211_sta *sta;

	struct ieee80211_vif *vif;

	struct ieee80211_hdr *hdr;

	unsigned int vif_id;



	rcu_read_lock();

	list_for_each_entry_rcu(iter, &ar->tx_ampdu_list, list) {

		if (iter->state < CARL9170_TID_STATE_IDLE)

			continue;



		spin_lock_bh(&iter->lock);

		skb = skb_peek(&iter->queue);

		if (!skb)

			goto unlock;



		txinfo = IEEE80211_SKB_CB(skb);

		arinfo = (void *)txinfo->rate_driver_data;

		if (time_is_after_jiffies(arinfo->timeout +

		    msecs_to_jiffies(CARL9170_QUEUE_TIMEOUT)))

			goto unlock;



		super = (void *) skb->data;

		hdr = (void *) super->frame_data;



		vif_id = (super->s.misc & CARL9170_TX_SUPER_MISC_VIF_ID) >>

			 CARL9170_TX_SUPER_MISC_VIF_ID_S;



		if (WARN_ON(vif_id >= AR9170_MAX_VIRTUAL_MAC))

			goto unlock;



		vif = rcu_dereference(ar->vif_priv[vif_id].vif);

		if (WARN_ON(!vif))

			goto unlock;



		sta = ieee80211_find_sta(vif, hdr->addr1);

		if (WARN_ON(!sta))

			goto unlock;



		ieee80211_stop_tx_ba_session(sta, iter->tid);

unlock:

		spin_unlock_bh(&iter->lock);



	}

	rcu_read_unlock();

}



void carl9170_tx_janitor(struct work_struct *work)

{

	struct ar9170 *ar = container_of(work, struct ar9170,
@@ -534,6 +587,7 @@ void carl9170_tx_janitor(struct work_struct *work) 
	ar->tx_janitor_last_run = jiffies;



	carl9170_check_queue_stop_timeout(ar);

	carl9170_tx_ampdu_timeout(ar);



	if (!atomic_read(&ar->tx_total_queued))

		return;

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