[PATCH 2/5] vfio: Move realize() after attach_device()

[Zhenzhong Duan <zhenzhong.duan@intel.com>]

Previously device attaching depends on realize() getting host iommu
capabilities to check dirty tracking support.

Now we save a caps copy in VFIODevice and check that copy for dirty
tracking support, there is no dependency any more, move realize()
call after attach_device() call in vfio_device_attach().

Drop vfio_device_hiod_realize() which looks redundant now.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Suggested-by: Donald Dutile <ddutile@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 include/hw/vfio/vfio-device.h |  1 -
 hw/vfio/container.c           |  4 ----
 hw/vfio/device.c              | 28 +++++++++++-----------------
 hw/vfio/iommufd.c             |  4 ----
 4 files changed, 11 insertions(+), 26 deletions(-)

diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h
index 09a7af891a..14559733c6 100644
--- a/include/hw/vfio/vfio-device.h
+++ b/include/hw/vfio/vfio-device.h
@@ -124,7 +124,6 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex
 
 void vfio_device_reset_handler(void *opaque);
 bool vfio_device_is_mdev(VFIODevice *vbasedev);
-bool vfio_device_hiod_realize(VFIODevice *vbasedev, Error **errp);
 bool vfio_device_attach(char *name, VFIODevice *vbasedev,
                         AddressSpace *as, Error **errp);
 void vfio_device_detach(VFIODevice *vbasedev);
diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index 23a3373470..676e88cef4 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -883,10 +883,6 @@ static bool vfio_legacy_attach_device(const char *name, VFIODevice *vbasedev,
 
     trace_vfio_device_attach(vbasedev->name, groupid);
 
-    if (!vfio_device_hiod_realize(vbasedev, errp)) {
-        return false;
-    }
-
     group = vfio_group_get(groupid, as, errp);
     if (!group) {
         return false;
diff --git a/hw/vfio/device.c b/hw/vfio/device.c
index 4de6948cf4..6154d3f443 100644
--- a/hw/vfio/device.c
+++ b/hw/vfio/device.c
@@ -347,17 +347,6 @@ bool vfio_device_is_mdev(VFIODevice *vbasedev)
     return subsys && (strcmp(subsys, "/sys/bus/mdev") == 0);
 }
 
-bool vfio_device_hiod_realize(VFIODevice *vbasedev, Error **errp)
-{
-    HostIOMMUDevice *hiod = vbasedev->hiod;
-
-    if (!hiod) {
-        return true;
-    }
-
-    return HOST_IOMMU_DEVICE_GET_CLASS(hiod)->realize(hiod, vbasedev, errp);
-}
-
 VFIODevice *vfio_get_vfio_device(Object *obj)
 {
     if (object_dynamic_cast(obj, TYPE_VFIO_PCI)) {
@@ -372,6 +361,7 @@ bool vfio_device_attach(char *name, VFIODevice *vbasedev,
 {
     const VFIOIOMMUClass *ops =
         VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_LEGACY));
+    HostIOMMUDeviceClass *hiodc;
     HostIOMMUDevice *hiod = NULL;
 
     if (vbasedev->iommufd) {
@@ -380,16 +370,20 @@ bool vfio_device_attach(char *name, VFIODevice *vbasedev,
 
     assert(ops);
 
+    if (!ops->attach_device(name, vbasedev, as, errp)) {
+        return false;
+    }
 
     if (!vbasedev->mdev) {
         hiod = HOST_IOMMU_DEVICE(object_new(ops->hiod_typename));
-        vbasedev->hiod = hiod;
-    }
+        hiodc = HOST_IOMMU_DEVICE_GET_CLASS(hiod);
 
-    if (!ops->attach_device(name, vbasedev, as, errp)) {
-        object_unref(hiod);
-        vbasedev->hiod = NULL;
-        return false;
+        if (!hiodc->realize(hiod, vbasedev, errp)) {
+            object_unref(hiod);
+            ops->detach_device(vbasedev);
+            return false;
+        }
+        vbasedev->hiod = hiod;
     }
 
     return true;
diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index 530cde6740..e05b472e35 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -502,10 +502,6 @@ static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
      * FD to be connected and having a devid to be able to successfully call
      * iommufd_backend_get_device_info().
      */
-    if (!vfio_device_hiod_realize(vbasedev, errp)) {
-        goto err_alloc_ioas;
-    }
-
     if (!iommufd_backend_get_device_info(vbasedev->iommufd, vbasedev->devid,
                                          &caps->type, &caps->vendor_caps,
                                          sizeof(VendorCaps), &caps->hw_caps,
-- 
2.34.1