[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>
diff --git a/drivers/scsi/aic94xx/aic94xx_dev.c b/drivers/scsi/aic94xx/aic94xx_dev.c
index 6f8901b..c520e5b 100644
--- a/drivers/scsi/aic94xx/aic94xx_dev.c
+++ b/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 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 @@
 
 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 @@
 		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 @@
 		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);
 }