ath9k: Fix powersave locking

The 'ps_flags' is used/accessed in a variety of contexts
and requires proper locking. Use 'sc_pm_lock' appropriately.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 34d6f26c6bc7..88f7ad106e05 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -345,7 +345,7 @@ void ath9k_tasklet(unsigned long data)
 	struct ath_softc *sc = (struct ath_softc *)data;
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
-
+	unsigned long flags;
 	u32 status = sc->intrstatus;
 	u32 rxmask;
 
@@ -369,6 +369,7 @@ void ath9k_tasklet(unsigned long data)
 		goto out;
 	}
 
+	spin_lock_irqsave(&sc->sc_pm_lock, flags);
 	if ((status & ATH9K_INT_TSFOOR) && sc->ps_enabled) {
 		/*
 		 * TSF sync does not look correct; remain awake to sync with
@@ -377,6 +378,7 @@ void ath9k_tasklet(unsigned long data)
 		ath_dbg(common, PS, "TSFOOR - Sync with next Beacon\n");
 		sc->ps_flags |= PS_WAIT_FOR_BEACON | PS_BEACON_SYNC;
 	}
+	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 
 	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
 		rxmask = (ATH9K_INT_RXHP | ATH9K_INT_RXLP | ATH9K_INT_RXEOL |
@@ -526,8 +528,10 @@ irqreturn_t ath_isr(int irq, void *dev)
 			/* Clear RxAbort bit so that we can
 			 * receive frames */
 			ath9k_setpower(sc, ATH9K_PM_AWAKE);
+			spin_lock(&sc->sc_pm_lock);
 			ath9k_hw_setrxabort(sc->sc_ah, 0);
 			sc->ps_flags |= PS_WAIT_FOR_BEACON;
+			spin_unlock(&sc->sc_pm_lock);
 		}
 
 chip_reset:
@@ -682,6 +686,7 @@ static void ath9k_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 	struct ath_tx_control txctl;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+	unsigned long flags;
 
 	if (sc->ps_enabled) {
 		/*
@@ -704,6 +709,7 @@ static void ath9k_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 		 * completed and if needed, also for RX of buffered frames.
 		 */
 		ath9k_ps_wakeup(sc);
+		spin_lock_irqsave(&sc->sc_pm_lock, flags);
 		if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP))
 			ath9k_hw_setrxabort(sc->sc_ah, 0);
 		if (ieee80211_is_pspoll(hdr->frame_control)) {
@@ -719,6 +725,7 @@ static void ath9k_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 		 * the ps_flags bit is cleared. We are just dropping
 		 * the ps_usecount here.
 		 */
+		spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 		ath9k_ps_restore(sc);
 	}
 
@@ -1479,7 +1486,7 @@ static void ath9k_bss_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 	struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
 	struct ath_vif *avp = (void *)vif->drv_priv;
-
+	unsigned long flags;
 	/*
 	 * Skip iteration if primary station vif's bss info
 	 * was not changed
@@ -1501,7 +1508,10 @@ static void ath9k_bss_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
 		 * on the receipt of the first Beacon frame (i.e.,
 		 * after time sync with the AP).
 		 */
+		spin_lock_irqsave(&sc->sc_pm_lock, flags);
 		sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
+		spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
+
 		/* Reset rssi stats */
 		sc->last_rssi = ATH_RSSI_DUMMY_MARKER;
 		sc->sc_ah->stats.avgbrssi = ATH_RSSI_DUMMY_MARKER;