Create host IOMMU device instance in vfio_attach_device() and call
.realize() to initialize it further.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 include/hw/vfio/vfio-common.h |  1 +
 hw/vfio/common.c              | 16 +++++++++++++++-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index affb73f209..94428abcf4 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -126,6 +126,7 @@ typedef struct VFIODevice {
     OnOffAuto pre_copy_dirty_page_tracking;
     bool dirty_pages_supported;
     bool dirty_tracking;
+    HostIOMMUDevice *hiod;
     int devid;
     IOMMUFDBackend *iommufd;
 } VFIODevice;
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 9f1f2e19f7..970c9e3a5f 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1497,6 +1497,7 @@ bool vfio_attach_device(char *name, VFIODevice *vbasedev,
 {
     const VFIOIOMMUClass *ops =
         VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_LEGACY));
+    HostIOMMUDevice *hiod;
 
     if (vbasedev->iommufd) {
         ops = VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
@@ -1504,7 +1505,19 @@ bool vfio_attach_device(char *name, VFIODevice *vbasedev,
 
     assert(ops);
 
-    return ops->attach_device(name, vbasedev, as, errp);
+    if (!ops->attach_device(name, vbasedev, as, errp)) {
+        return false;
+    }
+
+    hiod = HOST_IOMMU_DEVICE(object_new(ops->hiod_typename));
+    if (!HOST_IOMMU_DEVICE_GET_CLASS(hiod)->realize(hiod, vbasedev, errp)) {
+        object_unref(hiod);
+        ops->detach_device(vbasedev);
+        return false;
+    }
+    vbasedev->hiod = hiod;
+
+    return true;
 }
 
 void vfio_detach_device(VFIODevice *vbasedev)
@@ -1512,5 +1525,6 @@ void vfio_detach_device(VFIODevice *vbasedev)
     if (!vbasedev->bcontainer) {
         return;
     }
+    object_unref(vbasedev->hiod);
     vbasedev->bcontainer->ops->detach_device(vbasedev);
 }
-- 
2.34.1