[SCSI] aic94xx: Lock DDB read/write accesses

Extend the use of the DDB lock to include all DDB accesses, because
DDB updates now occur from multiple threads.  This fixes the SMP timeout
problems that we were occasionally seeing with a x260, because the
controller got confused when the DDBs got corrupted.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/aic94xx/aic94xx_dev.c

@@ -37,18 +37,14 @@
 
 static inline int asd_get_ddb(struct asd_ha_struct *asd_ha)
 {
-	unsigned long flags;
 	int ddb, i;
 
-	spin_lock_irqsave(&asd_ha->hw_prof.ddb_lock, flags);
 	ddb = FIND_FREE_DDB(asd_ha);
 	if (ddb >= asd_ha->hw_prof.max_ddbs) {
 		ddb = -ENOMEM;
-		spin_unlock_irqrestore(&asd_ha->hw_prof.ddb_lock, flags);
 		goto out;
 	}
 	SET_DDB(ddb, asd_ha);
-	spin_unlock_irqrestore(&asd_ha->hw_prof.ddb_lock, flags);
 
 	for (i = 0; i < sizeof(struct asd_ddb_ssp_smp_target_port); i+= 4)
 		asd_ddbsite_write_dword(asd_ha, ddb, i, 0);
@@ -77,14 +73,10 @@ static inline int asd_get_ddb(struct asd_ha_struct *asd_ha)
 
 static inline void asd_free_ddb(struct asd_ha_struct *asd_ha, int ddb)
 {
-	unsigned long flags;
-
 	if (!ddb || ddb >= 0xFFFF)
 		return;
 	asd_ddbsite_write_byte(asd_ha, ddb, DDB_TYPE, DDB_TYPE_UNUSED);
-	spin_lock_irqsave(&asd_ha->hw_prof.ddb_lock, flags);
 	CLEAR_DDB(ddb, asd_ha);
-	spin_unlock_irqrestore(&asd_ha->hw_prof.ddb_lock, flags);
 }
 
 static inline void asd_set_ddb_type(struct domain_device *dev)
@@ -320,8 +312,11 @@ static int asd_init_sata_pm_ddb(struct domain_device *dev)
 
 int asd_dev_found(struct domain_device *dev)
 {
+	unsigned long flags;
 	int res = 0;
+	struct asd_ha_struct *asd_ha = dev->port->ha->lldd_ha;
 
+	spin_lock_irqsave(&asd_ha->hw_prof.ddb_lock, flags);
 	switch (dev->dev_type) {
 	case SATA_PM:
 		res = asd_init_sata_pm_ddb(dev);
@@ -335,14 +330,18 @@ int asd_dev_found(struct domain_device *dev)
 		else
 			res = asd_init_initiator_ddb(dev);
 	}
+	spin_unlock_irqrestore(&asd_ha->hw_prof.ddb_lock, flags);
+
 	return res;
 }
 
 void asd_dev_gone(struct domain_device *dev)
 {
 	int ddb, sister_ddb;
+	unsigned long flags;
 	struct asd_ha_struct *asd_ha = dev->port->ha->lldd_ha;
 
+	spin_lock_irqsave(&asd_ha->hw_prof.ddb_lock, flags);
 	ddb = (int) (unsigned long) dev->lldd_dev;
 	sister_ddb = asd_ddbsite_read_word(asd_ha, ddb, SISTER_DDB);
 
@@ -350,4 +349,5 @@ void asd_dev_gone(struct domain_device *dev)
 		asd_free_ddb(asd_ha, sister_ddb);
 	asd_free_ddb(asd_ha, ddb);
 	dev->lldd_dev = NULL;
+	spin_unlock_irqrestore(&asd_ha->hw_prof.ddb_lock, flags);
 }

drivers/scsi/aic94xx/aic94xx_seq.c

@@ -1395,7 +1395,9 @@ void asd_update_port_links(struct asd_ha_struct *asd_ha, struct asd_phy *phy)
 	u8  phy_is_up;
 	u8  mask;
 	int i, err;
+	unsigned long flags;
 
+	spin_lock_irqsave(&asd_ha->hw_prof.ddb_lock, flags);
 	for_each_phy(phy_mask, mask, i)
 		asd_ddbsite_write_byte(asd_ha, 0,
 				       offsetof(struct asd_ddb_seq_shared,
@@ -1415,6 +1417,7 @@ void asd_update_port_links(struct asd_ha_struct *asd_ha, struct asd_phy *phy)
 			break;
 		}
 	}
+	spin_unlock_irqrestore(&asd_ha->hw_prof.ddb_lock, flags);
 
 	if (err)
 		asd_printk("couldn't update DDB 0:error:%d\n", err);