[PATCH] libsas: fix lockdep issue with ATA

[James Bottomley <James.Bottomley@SteelEye.com>]

lockdep noticed that with ATA support the port->dev_list_lock was
entangled at irq context, so it now needs to become IRQ safe

---
This applies against the aic94xx-sas-2.6 tree

James

diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c
index a18c0f6..ce3385c 100644
--- a/drivers/scsi/libsas/sas_discover.c
+++ b/drivers/scsi/libsas/sas_discover.c
@@ -292,9 +292,9 @@ static int sas_get_port_device(struct asd_sas_port *port)
 	port->disc.max_level = 0;
 
 	dev->rphy = rphy;
-	spin_lock(&port->dev_list_lock);
+	spin_lock_irqsave(&port->dev_list_lock, flags);
 	list_add_tail(&dev->dev_list_node, &port->dev_list);
-	spin_unlock(&port->dev_list_lock);
+	spin_unlock_irqrestore(&port->dev_list_lock, flags);
 
 	return 0;
 }
@@ -688,12 +688,14 @@ static void sas_discover_domain(struct work_struct *work)
 	}
 
 	if (error) {
+		unsigned long flags;
+
 		sas_rphy_free(dev->rphy);
 		dev->rphy = NULL;
 
-		spin_lock(&port->dev_list_lock);
+		spin_lock_irqsave(&port->dev_list_lock, flags);
 		list_del_init(&dev->dev_list_node);
-		spin_unlock(&port->dev_list_lock);
+		spin_unlock_irqrestore(&port->dev_list_lock, flags);
 
 		kfree(dev); /* not kobject_register-ed yet */
 		port->port_dev = NULL;
diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
index d05fc23..1c15f37 100644
--- a/drivers/scsi/libsas/sas_expander.c
+++ b/drivers/scsi/libsas/sas_expander.c
@@ -628,6 +628,7 @@ static struct domain_device *sas_ex_discover_end_dev(
 	struct domain_device *child = NULL;
 	struct sas_rphy *rphy;
 	int res;
+	unsigned long flags;
 
 	if (phy->attached_sata_host || phy->attached_sata_ps)
 		return NULL;
@@ -677,9 +678,9 @@ static struct domain_device *sas_ex_discover_end_dev(
 
 		child->rphy = rphy;
 
-		spin_lock(&parent->port->dev_list_lock);
+		spin_lock_irqsave(&parent->port->dev_list_lock, flags);
 		list_add_tail(&child->dev_list_node, &parent->port->dev_list);
-		spin_unlock(&parent->port->dev_list_lock);
+		spin_unlock_irqrestore(&parent->port->dev_list_lock, flags);
 
 		res = sas_discover_sata(child);
 		if (res) {
@@ -701,9 +702,9 @@ static struct domain_device *sas_ex_discover_end_dev(
 		child->rphy = rphy;
 		sas_fill_in_rphy(child, rphy);
 
-		spin_lock(&parent->port->dev_list_lock);
+		spin_lock_irqsave(&parent->port->dev_list_lock, flags);
 		list_add_tail(&child->dev_list_node, &parent->port->dev_list);
-		spin_unlock(&parent->port->dev_list_lock);
+		spin_unlock_irqrestore(&parent->port->dev_list_lock, flags);
 
 		res = sas_discover_end_dev(child);
 		if (res) {
@@ -767,6 +768,7 @@ static struct domain_device *sas_ex_discover_expander(
 	struct sas_expander_device *edev;
 	struct asd_sas_port *port;
 	int res;
+	unsigned long flags;
 
 	if (phy->routing_attr == DIRECT_ROUTING) {
 		SAS_DPRINTK("ex %016llx:0x%x:D <--> ex %016llx:0x%x is not "
@@ -816,9 +818,9 @@ static struct domain_device *sas_ex_discover_expander(
 	sas_fill_in_rphy(child, rphy);
 	sas_rphy_add(rphy);
 
-	spin_lock(&parent->port->dev_list_lock);
+	spin_lock_irqsave(&parent->port->dev_list_lock, flags);
 	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
-	spin_unlock(&parent->port->dev_list_lock);
+	spin_unlock_irqrestore(&parent->port->dev_list_lock, flags);
 
 	res = sas_discover_expander(child);
 	if (res) {