vmw_pvscsi: Introduce 'x-disable-pcie' backword compatability property

Following the previous patch which changed pvscsi to be a pci express
device, this patch introduces a boolean property 'x-disable-pcie'.

Its default value is false, exposing pvscsi as a pcie device.

Setting 'x-disable-pcie' to 'on' preserves the old 'pci device' (non
express) behavior. This allows migration to older versions.
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Message-Id: <1449994112-7054-7-git-send-email-shmulik.ladkani@ravellosystems.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

hw/scsi/vmw_pvscsi.c

@@ -1241,6 +1241,8 @@ static Property pvscsi_properties[] = {
     DEFINE_PROP_UINT8("use_msg", PVSCSIState, use_msg, 1),
     DEFINE_PROP_BIT("x-old-pci-configuration", PVSCSIState, compat_flags,
                     PVSCSI_COMPAT_OLD_PCI_CONFIGURATION_BIT, false),
+    DEFINE_PROP_BIT("x-disable-pcie", PVSCSIState, compat_flags,
+                    PVSCSI_COMPAT_DISABLE_PCIE_BIT, false),
     DEFINE_PROP_END_OF_LIST(),
 };
 

include/hw/compat.h

@@ -10,6 +10,10 @@
             .driver   = "pvscsi",\
             .property = "x-old-pci-configuration",\
             .value    = "on",\
+        },{\
+            .driver   = "pvscsi",\
+            .property = "x-disable-pcie",\
+            .value    = "on",\
         },{\
             .driver   = "e1000",\
             .property = "extra_mac_registers",\