[SCSI] libsas: mark all domain devices gone if root port disappears

If the top level expander is hot removed, mark all child devices as gone
before unregistration to short circuit futile recovery.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

drivers/scsi/libsas/sas_discover.c

@@ -299,12 +299,16 @@ void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
 	}
 }
 
-void sas_unregister_domain_devices(struct asd_sas_port *port)
+void sas_unregister_domain_devices(struct asd_sas_port *port, int gone)
 {
 	struct domain_device *dev, *n;
 
-	list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node)
+	list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node) {
+		if (gone)
+			set_bit(SAS_DEV_GONE, &dev->state);
 		sas_unregister_dev(port, dev);
+	}
+
 	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node)
 		sas_unregister_dev(port, dev);
 

drivers/scsi/libsas/sas_port.c

@@ -167,9 +167,7 @@ void sas_deform_port(struct asd_sas_phy *phy, int gone)
 		dev->pathways--;
 
 	if (port->num_phys == 1) {
-		if (dev && gone)
-			set_bit(SAS_DEV_GONE, &dev->state);
-		sas_unregister_domain_devices(port);
+		sas_unregister_domain_devices(port, gone);
 		sas_port_delete(port->port);
 		port->port = NULL;
 	} else {

include/scsi/libsas.h

@@ -664,7 +664,7 @@ void sas_init_ex_attr(void);
 
 int  sas_ex_revalidate_domain(struct domain_device *);
 
-void sas_unregister_domain_devices(struct asd_sas_port *port);
+void sas_unregister_domain_devices(struct asd_sas_port *port, int gone);
 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *);
 int  sas_discover_event(struct asd_sas_port *, enum discover_event ev);