HostIOMMUDevice will be inherited by two sub classes,
legacy and iommufd currently.

Introduce a helper function host_iommu_base_device_init to initialize it.

Suggested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 include/sysemu/host_iommu_device.h | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 include/sysemu/host_iommu_device.h

diff --git a/include/sysemu/host_iommu_device.h b/include/sysemu/host_iommu_device.h
new file mode 100644
index 0000000000..fe80ab25fb
--- /dev/null
+++ b/include/sysemu/host_iommu_device.h
@@ -0,0 +1,22 @@
+#ifndef HOST_IOMMU_DEVICE_H
+#define HOST_IOMMU_DEVICE_H
+
+typedef enum HostIOMMUDevice_Type {
+    HID_LEGACY,
+    HID_IOMMUFD,
+    HID_MAX,
+} HostIOMMUDevice_Type;
+
+typedef struct HostIOMMUDevice {
+    HostIOMMUDevice_Type type;
+    size_t size;
+} HostIOMMUDevice;
+
+static inline void host_iommu_base_device_init(HostIOMMUDevice *dev,
+                                               HostIOMMUDevice_Type type,
+                                               size_t size)
+{
+    dev->type = type;
+    dev->size = size;
+}
+#endif
-- 
2.34.1