vfio: Introduce a helper function to initialize VFIODevice

Introduce a helper function to replace the common code to initialize
VFIODevice in pci, platform, ap and ccw VFIO device.

No functional change intended.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>

hw/vfio/ap.c

@@ -226,18 +226,14 @@ static void vfio_ap_instance_init(Object *obj)
     VFIOAPDevice *vapdev = VFIO_AP_DEVICE(obj);
     VFIODevice *vbasedev = &vapdev->vdev;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_AP;
-    vbasedev->ops = &vfio_ap_ops;
-    vbasedev->dev = DEVICE(vapdev);
-    vbasedev->fd = -1;
-
     /*
      * vfio-ap devices operate in a way compatible with discarding of
      * memory in RAM blocks, as no pages are pinned in the host.
      * This needs to be set before vfio_get_device() for vfio common to
      * handle ram_block_discard_disable().
      */
-    vbasedev->ram_block_discard_allowed = true;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_AP, &vfio_ap_ops,
+                     DEVICE(vapdev), true);
 }
 
 #ifdef CONFIG_IOMMUFD

hw/vfio/ccw.c

@@ -683,11 +683,6 @@ static void vfio_ccw_instance_init(Object *obj)
     VFIOCCWDevice *vcdev = VFIO_CCW(obj);
     VFIODevice *vbasedev = &vcdev->vdev;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_CCW;
-    vbasedev->ops = &vfio_ccw_ops;
-    vbasedev->dev = DEVICE(vcdev);
-    vbasedev->fd = -1;
-
     /*
      * All vfio-ccw devices are believed to operate in a way compatible with
      * discarding of memory in RAM blocks, ie. pages pinned in the host are
@@ -696,7 +691,8 @@ static void vfio_ccw_instance_init(Object *obj)
      * needs to be set before vfio_get_device() for vfio common to handle
      * ram_block_discard_disable().
      */
-    vbasedev->ram_block_discard_allowed = true;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_CCW, &vfio_ccw_ops,
+                     DEVICE(vcdev), true);
 }
 
 #ifdef CONFIG_IOMMUFD

hw/vfio/helpers.c

@@ -652,3 +652,14 @@ void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp)
     }
     vbasedev->fd = fd;
 }
+
+void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
+                      DeviceState *dev, bool ram_discard)
+{
+    vbasedev->type = type;
+    vbasedev->ops = ops;
+    vbasedev->dev = dev;
+    vbasedev->fd = -1;
+
+    vbasedev->ram_block_discard_allowed = ram_discard;
+}

hw/vfio/pci.c

@@ -3327,10 +3327,8 @@ static void vfio_instance_init(Object *obj)
     vdev->host.slot = ~0U;
     vdev->host.function = ~0U;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_PCI;
-    vbasedev->ops = &vfio_pci_ops;
-    vbasedev->dev = DEVICE(vdev);
-    vbasedev->fd = -1;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PCI, &vfio_pci_ops,
+                     DEVICE(vdev), false);
 
     vdev->nv_gpudirect_clique = 0xFF;
 

hw/vfio/platform.c

@@ -657,10 +657,8 @@ static void vfio_platform_instance_init(Object *obj)
     VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(obj);
     VFIODevice *vbasedev = &vdev->vbasedev;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_PLATFORM;
-    vbasedev->ops = &vfio_platform_ops;
-    vbasedev->dev = DEVICE(vdev);
-    vbasedev->fd = -1;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PLATFORM, &vfio_platform_ops,
+                     DEVICE(vdev), false);
 }
 
 #ifdef CONFIG_IOMMUFD

include/hw/vfio/vfio-common.h

@@ -257,4 +257,6 @@ int vfio_get_dirty_bitmap(const VFIOContainerBase *bcontainer, uint64_t iova,
 /* Returns 0 on success, or a negative errno. */
 int vfio_device_get_name(VFIODevice *vbasedev, Error **errp);
 void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp);
+void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
+                      DeviceState *dev, bool ram_discard);
 #endif /* HW_VFIO_VFIO_COMMON_H */