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>

3 files changed, 21 insertions, 9 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;
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index b54e15941ba4..fbdcc80437fe 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -587,13 +587,13 @@ static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb, bool mybeacon)
 
         /* Process Beacon and CAB receive in PS state */
         if (((sc->ps_flags & PS_WAIT_FOR_BEACON) || ath9k_check_auto_sleep(sc))
-            && mybeacon)
+            && mybeacon) {
                 ath_rx_ps_beacon(sc, skb);
-        else if ((sc->ps_flags & PS_WAIT_FOR_CAB) &&
-                 (ieee80211_is_data(hdr->frame_control) ||
-                  ieee80211_is_action(hdr->frame_control)) &&
-                 is_multicast_ether_addr(hdr->addr1) &&
-                 !ieee80211_has_moredata(hdr->frame_control)) {
+        } else if ((sc->ps_flags & PS_WAIT_FOR_CAB) &&
+                   (ieee80211_is_data(hdr->frame_control) ||
+                    ieee80211_is_action(hdr->frame_control)) &&
+                   is_multicast_ether_addr(hdr->addr1) &&
+                   !ieee80211_has_moredata(hdr->frame_control)) {
                 /*
                  * No more broadcast/multicast frames to be received at this
                  * point.
@@ -1229,7 +1229,6 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
                         skb_trim(skb, skb->len - 8);
 
                 spin_lock_irqsave(&sc->sc_pm_lock, flags);
-
                 if ((sc->ps_flags & (PS_WAIT_FOR_BEACON |
                                      PS_WAIT_FOR_CAB |
                                      PS_WAIT_FOR_PSPOLL_DATA)) ||
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index bb74780903d5..f777ddcd1172 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -1994,6 +1994,7 @@ static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
         struct ieee80211_hdr * hdr = (struct ieee80211_hdr *)skb->data;
         int q, padpos, padsize;
+        unsigned long flags;
 
         ath_dbg(common, XMIT, "TX complete: skb: %p\n", skb);
 
@@ -2012,6 +2013,7 @@ static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
                 skb_pull(skb, padsize);
         }
 
+        spin_lock_irqsave(&sc->sc_pm_lock, flags);
         if ((sc->ps_flags & PS_WAIT_FOR_TX_ACK) && !txq->axq_depth) {
                 sc->ps_flags &= ~PS_WAIT_FOR_TX_ACK;
                 ath_dbg(common, PS,
@@ -2021,6 +2023,7 @@ static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
                                         PS_WAIT_FOR_PSPOLL_DATA |
                                         PS_WAIT_FOR_TX_ACK));
         }
+        spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 
         q = skb_get_queue_mapping(skb);
         if (txq == sc->tx.txq_map[q]) {