[RFC 18/18] vfio/pci: Add an iommufd option

[Yi Liu <yi.l.liu@xxxxxxxxx>]

From: Eric Auger <eric.auger@xxxxxxxxxx>

This auto/on/off option allows the user to force a the select
the iommu BE (iommufd or legacy).

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
---
 hw/vfio/pci.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index cf5703f94b..70a4c2b0a8 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -42,6 +42,8 @@
 #include "qapi/error.h"
 #include "migration/blocker.h"
 #include "migration/qemu-file.h"
+#include "qapi/visitor.h"
+#include "qapi/qapi-visit-common.h"
 
 #define TYPE_VFIO_PCI_NOHOTPLUG "vfio-pci-nohotplug"
 
@@ -3246,6 +3248,26 @@ static Property vfio_pci_dev_properties[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
+static void get_iommu_be(Object *obj, Visitor *v, const char *name,
+                         void *opaque, Error **errp)
+{
+    VFIOPCIDevice *vdev = VFIO_PCI(obj);
+    VFIODevice *vbasedev = &vdev->vbasedev;
+    OnOffAuto iommufd_be = vbasedev->iommufd_be;
+
+    visit_type_OnOffAuto(v, name, &iommufd_be, errp);
+}
+
+static void set_iommu_be(Object *obj, Visitor *v, const char *name,
+                         void *opaque, Error **errp)
+{
+    VFIOPCIDevice *vdev = VFIO_PCI(obj);
+    VFIODevice *vbasedev = &vdev->vbasedev;
+
+    visit_type_OnOffAuto(v, name, &vbasedev->iommufd_be, errp);
+}
+
+
 static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -3253,6 +3275,10 @@ static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
 
     dc->reset = vfio_pci_reset;
     device_class_set_props(dc, vfio_pci_dev_properties);
+    object_class_property_add(klass, "iommufd", "OnOffAuto",
+                              get_iommu_be, set_iommu_be, NULL, NULL);
+    object_class_property_set_description(klass, "iommufd",
+                                          "Enable iommufd backend");
     dc->desc = "VFIO-based PCI device assignment";
     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
     pdc->realize = vfio_realize;
-- 
2.27.0