ath9k: Use atomic operations

The 'sc_flags' variable is being used in a number of places
with no locking whatsoever. This patch converts the usage
of sc_flags to atomic ops.

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

drivers/net/wireless/ath/ath9k/ahb.c

@@ -126,7 +126,7 @@ static int ath_ahb_probe(struct platform_device *pdev)
 	sc->irq = irq;
 
 	/* Will be cleared in ath9k_start() */
-	sc->sc_flags |= SC_OP_INVALID;
+	set_bit(SC_OP_INVALID, &sc->sc_flags);
 
 	ret = request_irq(irq, ath_isr, IRQF_SHARED, "ath9k", sc);
 	if (ret) {

drivers/net/wireless/ath/ath9k/ath9k.h

@@ -604,12 +604,14 @@ void ath_ant_comb_update(struct ath_softc *sc);
 #define ATH_TXPOWER_MAX         100     /* .5 dBm units */
 #define ATH_RATE_DUMMY_MARKER   0
 
-#define SC_OP_INVALID                BIT(0)
-#define SC_OP_BEACONS                BIT(1)
-#define SC_OP_RXFLUSH                BIT(2)
-#define SC_OP_TSF_RESET              BIT(3)
-#define SC_OP_ANI_RUN                BIT(4)
-#define SC_OP_PRIM_STA_VIF           BIT(5)
+enum sc_op_flags {
+	SC_OP_INVALID,
+	SC_OP_BEACONS,
+	SC_OP_RXFLUSH,
+	SC_OP_TSF_RESET,
+	SC_OP_ANI_RUN,
+	SC_OP_PRIM_STA_VIF,
+};
 
 /* Powersave flags */
 #define PS_WAIT_FOR_BEACON        BIT(0)
@@ -655,9 +657,9 @@ struct ath_softc {
 	struct completion paprd_complete;
 
 	unsigned int hw_busy_count;
+	unsigned long sc_flags;
 
 	u32 intrstatus;
-	u32 sc_flags; /* SC_OP_* */
 	u16 ps_flags; /* PS_* */
 	u16 curtxpow;
 	bool ps_enabled;

drivers/net/wireless/ath/ath9k/beacon.c

@@ -390,7 +390,7 @@ void ath_beacon_tasklet(unsigned long data)
 		} else if (sc->beacon.bmisscnt >= BSTUCK_THRESH) {
 			ath_dbg(common, BSTUCK, "beacon is officially stuck\n");
 			sc->beacon.bmisscnt = 0;
-			sc->sc_flags |= SC_OP_TSF_RESET;
+			set_bit(SC_OP_TSF_RESET, &sc->sc_flags);
 			ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
 		}
 
@@ -480,16 +480,16 @@ static void ath9k_beacon_init(struct ath_softc *sc,
 			      u32 next_beacon,
 			      u32 beacon_period)
 {
-	if (sc->sc_flags & SC_OP_TSF_RESET) {
+	if (test_bit(SC_OP_TSF_RESET, &sc->sc_flags)) {
 		ath9k_ps_wakeup(sc);
 		ath9k_hw_reset_tsf(sc->sc_ah);
 	}
 
 	ath9k_hw_beaconinit(sc->sc_ah, next_beacon, beacon_period);
 
-	if (sc->sc_flags & SC_OP_TSF_RESET) {
+	if (test_bit(SC_OP_TSF_RESET, &sc->sc_flags)) {
 		ath9k_ps_restore(sc);
-		sc->sc_flags &= ~SC_OP_TSF_RESET;
+		clear_bit(SC_OP_TSF_RESET, &sc->sc_flags);
 	}
 }
 
@@ -519,7 +519,7 @@ static void ath_beacon_config_ap(struct ath_softc *sc,
 	/* Set the computed AP beacon timers */
 
 	ath9k_hw_disable_interrupts(ah);
-	sc->sc_flags |= SC_OP_TSF_RESET;
+	set_bit(SC_OP_TSF_RESET, &sc->sc_flags);
 	ath9k_beacon_init(sc, nexttbtt, intval);
 	sc->beacon.bmisscnt = 0;
 	ath9k_hw_set_interrupts(ah);
@@ -662,7 +662,7 @@ static void ath_beacon_config_adhoc(struct ath_softc *sc,
 	u32 tsf, intval, nexttbtt;
 
 	ath9k_reset_beacon_status(sc);
-	if (!(sc->sc_flags & SC_OP_BEACONS))
+	if (!test_bit(SC_OP_BEACONS, &sc->sc_flags))
 		ath9k_hw_settsf64(ah, sc->beacon.bc_tstamp);
 
 	intval = TU_TO_USEC(conf->beacon_interval);
@@ -727,7 +727,7 @@ static bool ath9k_allow_beacon_config(struct ath_softc *sc,
 	 */
 	if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
 	    (vif->type == NL80211_IFTYPE_STATION) &&
-	    (sc->sc_flags & SC_OP_BEACONS) &&
+	    test_bit(SC_OP_BEACONS, &sc->sc_flags) &&
 	    !avp->primary_sta_vif) {
 		ath_dbg(common, CONFIG,
 			"Beacon already configured for a station interface\n");
@@ -813,15 +813,15 @@ void ath_set_beacon(struct ath_softc *sc)
 		return;
 	}
 
-	sc->sc_flags |= SC_OP_BEACONS;
+	set_bit(SC_OP_BEACONS, &sc->sc_flags);
 }
 
 void ath9k_set_beaconing_status(struct ath_softc *sc, bool status)
 {
 	struct ath_hw *ah = sc->sc_ah;
 
 	if (!ath_has_valid_bslot(sc)) {
-		sc->sc_flags &= ~SC_OP_BEACONS;
+		clear_bit(SC_OP_BEACONS, &sc->sc_flags);
 		return;
 	}
 

drivers/net/wireless/ath/ath9k/debug.c

@@ -205,10 +205,10 @@ static ssize_t write_file_disable_ani(struct file *file,
 	common->disable_ani = !!disable_ani;
 
 	if (disable_ani) {
-		sc->sc_flags &= ~SC_OP_ANI_RUN;
+		clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 		del_timer_sync(&common->ani.timer);
 	} else {
-		sc->sc_flags |= SC_OP_ANI_RUN;
+		set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 		ath_start_ani(common);
 	}
 
@@ -1321,7 +1321,7 @@ static int open_file_bb_mac_samps(struct inode *inode, struct file *file)
 	u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
 	u8 nread;
 
-	if (sc->sc_flags & SC_OP_INVALID)
+	if (test_bit(SC_OP_INVALID, &sc->sc_flags))
 		return -EAGAIN;
 
 	buf = vmalloc(size);

drivers/net/wireless/ath/ath9k/link.c

@@ -155,7 +155,7 @@ void ath_start_rx_poll(struct ath_softc *sc, u8 nbeacon)
 	if (!AR_SREV_9300(sc->sc_ah))
 		return;
 
-	if (!(sc->sc_flags & SC_OP_PRIM_STA_VIF))
+	if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
 		return;
 
 	mod_timer(&sc->rx_poll_timer, jiffies + msecs_to_jiffies
@@ -430,7 +430,7 @@ void ath_start_ani(struct ath_common *common)
 	unsigned long timestamp = jiffies_to_msecs(jiffies);
 	struct ath_softc *sc = (struct ath_softc *) common->priv;
 
-	if (!(sc->sc_flags & SC_OP_ANI_RUN))
+	if (!test_bit(SC_OP_ANI_RUN, &sc->sc_flags))
 		return;
 
 	if (sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL)

drivers/net/wireless/ath/ath9k/main.c

@@ -222,7 +222,7 @@ static bool ath_complete_reset(struct ath_softc *sc, bool start)
 	ath9k_hw_enable_interrupts(ah);
 
 	if (!(sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL) && start) {
-		if (sc->sc_flags & SC_OP_BEACONS)
+		if (test_bit(SC_OP_BEACONS, &sc->sc_flags))
 			ath_set_beacon(sc);
 
 		ath_restart_work(sc);
@@ -293,7 +293,7 @@ static int ath_set_channel(struct ath_softc *sc, struct ieee80211_hw *hw,
 {
 	int r;
 
-	if (sc->sc_flags & SC_OP_INVALID)
+	if (test_bit(SC_OP_INVALID, &sc->sc_flags))
 		return -EIO;
 
 	r = ath_reset_internal(sc, hchan, false);
@@ -435,7 +435,7 @@ irqreturn_t ath_isr(int irq, void *dev)
 	 * touch anything. Note this can happen early
 	 * on if the IRQ is shared.
 	 */
-	if (sc->sc_flags & SC_OP_INVALID)
+	if (test_bit(SC_OP_INVALID, &sc->sc_flags))
 		return IRQ_NONE;
 
 
@@ -635,7 +635,7 @@ static int ath9k_start(struct ieee80211_hw *hw)
 
 	ath_mci_enable(sc);
 
-	sc->sc_flags &= ~SC_OP_INVALID;
+	clear_bit(SC_OP_INVALID, &sc->sc_flags);
 	sc->sc_ah->is_monitoring = false;
 
 	if (!ath_complete_reset(sc, false)) {
@@ -754,7 +754,7 @@ static void ath9k_stop(struct ieee80211_hw *hw)
 	ath_cancel_work(sc);
 	del_timer_sync(&sc->rx_poll_timer);
 
-	if (sc->sc_flags & SC_OP_INVALID) {
+	if (test_bit(SC_OP_INVALID, &sc->sc_flags)) {
 		ath_dbg(common, ANY, "Device not present\n");
 		mutex_unlock(&sc->mutex);
 		return;
@@ -811,7 +811,7 @@ static void ath9k_stop(struct ieee80211_hw *hw)
 
 	ath9k_ps_restore(sc);
 
-	sc->sc_flags |= SC_OP_INVALID;
+	set_bit(SC_OP_INVALID, &sc->sc_flags);
 	sc->ps_idle = prev_idle;
 
 	mutex_unlock(&sc->mutex);
@@ -915,11 +915,11 @@ static void ath9k_calculate_summary_state(struct ieee80211_hw *hw,
 	/* Set op-mode & TSF */
 	if (iter_data.naps > 0) {
 		ath9k_hw_set_tsfadjust(ah, 1);
-		sc->sc_flags |= SC_OP_TSF_RESET;
+		set_bit(SC_OP_TSF_RESET, &sc->sc_flags);
 		ah->opmode = NL80211_IFTYPE_AP;
 	} else {
 		ath9k_hw_set_tsfadjust(ah, 0);
-		sc->sc_flags &= ~SC_OP_TSF_RESET;
+		clear_bit(SC_OP_TSF_RESET, &sc->sc_flags);
 
 		if (iter_data.nmeshes)
 			ah->opmode = NL80211_IFTYPE_MESH_POINT;
@@ -950,12 +950,12 @@ static void ath9k_calculate_summary_state(struct ieee80211_hw *hw,
 		sc->sc_ah->stats.avgbrssi = ATH_RSSI_DUMMY_MARKER;
 
 		if (!common->disable_ani) {
-			sc->sc_flags |= SC_OP_ANI_RUN;
+			set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 			ath_start_ani(common);
 		}
 
 	} else {
-		sc->sc_flags &= ~SC_OP_ANI_RUN;
+		clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 		del_timer_sync(&common->ani.timer);
 	}
 }
@@ -1479,11 +1479,11 @@ static void ath9k_bss_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
 	 * Skip iteration if primary station vif's bss info
 	 * was not changed
 	 */
-	if (sc->sc_flags & SC_OP_PRIM_STA_VIF)
+	if (test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
 		return;
 
 	if (bss_conf->assoc) {
-		sc->sc_flags |= SC_OP_PRIM_STA_VIF;
+		set_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags);
 		avp->primary_sta_vif = true;
 		memcpy(common->curbssid, bss_conf->bssid, ETH_ALEN);
 		common->curaid = bss_conf->aid;
@@ -1504,7 +1504,7 @@ static void ath9k_bss_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
 		ath_start_rx_poll(sc, 3);
 
 		if (!common->disable_ani) {
-			sc->sc_flags |= SC_OP_ANI_RUN;
+			set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 			ath_start_ani(common);
 		}
 
@@ -1524,7 +1524,8 @@ static void ath9k_config_bss(struct ath_softc *sc, struct ieee80211_vif *vif)
 	if (avp->primary_sta_vif && !bss_conf->assoc) {
 		ath_dbg(common, CONFIG, "Bss Info DISASSOC %d, bssid %pM\n",
 			common->curaid, common->curbssid);
-		sc->sc_flags &= ~(SC_OP_PRIM_STA_VIF | SC_OP_BEACONS);
+		clear_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags);
+		clear_bit(SC_OP_BEACONS, &sc->sc_flags);
 		avp->primary_sta_vif = false;
 		memset(common->curbssid, 0, ETH_ALEN);
 		common->curaid = 0;
@@ -1537,10 +1538,9 @@ static void ath9k_config_bss(struct ath_softc *sc, struct ieee80211_vif *vif)
 	 * None of station vifs are associated.
 	 * Clear bssid & aid
 	 */
-	if (!(sc->sc_flags & SC_OP_PRIM_STA_VIF)) {
+	if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags)) {
 		ath9k_hw_write_associd(sc->sc_ah);
-		/* Stop ANI */
-		sc->sc_flags &= ~SC_OP_ANI_RUN;
+		clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 		del_timer_sync(&common->ani.timer);
 		del_timer_sync(&sc->rx_poll_timer);
 		memset(&sc->caldata, 0, sizeof(sc->caldata));
@@ -1578,12 +1578,12 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 			sc->sc_ah->stats.avgbrssi = ATH_RSSI_DUMMY_MARKER;
 
 			if (!common->disable_ani) {
-				sc->sc_flags |= SC_OP_ANI_RUN;
+				set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 				ath_start_ani(common);
 			}
 
 		} else {
-			sc->sc_flags &= ~SC_OP_ANI_RUN;
+			clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
 			del_timer_sync(&common->ani.timer);
 			del_timer_sync(&sc->rx_poll_timer);
 		}
@@ -1595,7 +1595,7 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 	 */
 	if ((changed & BSS_CHANGED_BEACON_INT) &&
 	    (vif->type == NL80211_IFTYPE_AP))
-		sc->sc_flags |= SC_OP_TSF_RESET;
+		set_bit(SC_OP_TSF_RESET, &sc->sc_flags);
 
 	/* Configure beaconing (AP, IBSS, MESH) */
 	if (ath9k_uses_beacons(vif->type) &&
@@ -1787,7 +1787,7 @@ static void ath9k_flush(struct ieee80211_hw *hw, bool drop)
 		return;
 	}
 
-	if (sc->sc_flags & SC_OP_INVALID) {
+	if (test_bit(SC_OP_INVALID, &sc->sc_flags)) {
 		ath_dbg(common, ANY, "Device not present\n");
 		mutex_unlock(&sc->mutex);
 		return;

drivers/net/wireless/ath/ath9k/pci.c

@@ -251,7 +251,7 @@ static int ath_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	sc->mem = mem;
 
 	/* Will be cleared in ath9k_start() */
-	sc->sc_flags |= SC_OP_INVALID;
+	set_bit(SC_OP_INVALID, &sc->sc_flags);
 
 	ret = request_irq(pdev->irq, ath_isr, IRQF_SHARED, "ath9k", sc);
 	if (ret) {

drivers/net/wireless/ath/ath9k/recv.c

@@ -285,8 +285,8 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
 	int error = 0;
 
 	spin_lock_init(&sc->sc_pcu_lock);
-	sc->sc_flags &= ~SC_OP_RXFLUSH;
 	spin_lock_init(&sc->rx.rxbuflock);
+	clear_bit(SC_OP_RXFLUSH, &sc->sc_flags);
 
 	common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +
 			     sc->sc_ah->caps.rx_status_len;
@@ -498,11 +498,11 @@ bool ath_stoprecv(struct ath_softc *sc)
 
 void ath_flushrecv(struct ath_softc *sc)
 {
-	sc->sc_flags |= SC_OP_RXFLUSH;
+	set_bit(SC_OP_RXFLUSH, &sc->sc_flags);
 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
 		ath_rx_tasklet(sc, 1, true);
 	ath_rx_tasklet(sc, 1, false);
-	sc->sc_flags &= ~SC_OP_RXFLUSH;
+	clear_bit(SC_OP_RXFLUSH, &sc->sc_flags);
 }
 
 static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
@@ -1063,7 +1063,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
 
 	do {
 		/* If handling rx interrupt and flush is in progress => exit */
-		if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
+		if (test_bit(SC_OP_RXFLUSH, &sc->sc_flags) && (flush == 0))
 			break;
 
 		memset(&rs, 0, sizeof(rs));
@@ -1108,7 +1108,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
 		 * If we're asked to flush receive queue, directly
 		 * chain it back at the queue without processing it.
 		 */
-		if (sc->sc_flags & SC_OP_RXFLUSH) {
+		if (test_bit(SC_OP_RXFLUSH, &sc->sc_flags)) {
 			RX_STAT_INC(rx_drop_rxflush);
 			goto requeue_drop_frag;
 		}

drivers/net/wireless/ath/ath9k/xmit.c

@@ -1536,7 +1536,7 @@ bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
 	int i;
 	u32 npend = 0;
 
-	if (sc->sc_flags & SC_OP_INVALID)
+	if (test_bit(SC_OP_INVALID, &sc->sc_flags))
 		return true;
 
 	ath9k_hw_abort_tx_dma(ah);