2012-06-04 14:55:17

by Sujith Manoharan

[permalink] [raw]
Subject: [PATCH 6/7] 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 <[email protected]>
---
drivers/net/wireless/ath/ath9k/main.c | 14 ++++++++++++--
drivers/net/wireless/ath/ath9k/recv.c | 13 ++++++-------
drivers/net/wireless/ath/ath9k/xmit.c | 3 +++
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 6ff33c9..953888b 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 3ac52c5..1cf4fc8 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 bb74780..f777ddc 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]) {
--
1.7.10.3