[PULL v2 16/32] vfio: Make vfio-pci device migration capable

[Alex Williamson <alex.williamson@redhat.com>]

From: Kirti Wankhede <kwankhede@nvidia.com>

If the device is not a failover primary device, call
vfio_migration_probe() and vfio_migration_finalize() to enable
migration support for those devices that support it respectively to
tear it down again.
Removed migration blocker from VFIO PCI device specific structure and use
migration blocker from generic structure of  VFIO device.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
 hw/vfio/pci.c |   28 ++++++++--------------------
 hw/vfio/pci.h |    1 -
 2 files changed, 8 insertions(+), 21 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index e27c88be6d85..58c0ce8971e3 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2791,17 +2791,6 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
         return;
     }
 
-    if (!pdev->failover_pair_id) {
-        error_setg(&vdev->migration_blocker,
-                "VFIO device doesn't support migration");
-        ret = migrate_add_blocker(vdev->migration_blocker, errp);
-        if (ret) {
-            error_free(vdev->migration_blocker);
-            vdev->migration_blocker = NULL;
-            return;
-        }
-    }
-
     vdev->vbasedev.name = g_path_get_basename(vdev->vbasedev.sysfsdev);
     vdev->vbasedev.ops = &vfio_pci_ops;
     vdev->vbasedev.type = VFIO_DEVICE_TYPE_PCI;
@@ -3069,6 +3058,13 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
         }
     }
 
+    if (!pdev->failover_pair_id) {
+        ret = vfio_migration_probe(&vdev->vbasedev, errp);
+        if (ret) {
+            error_report("%s: Migration disabled", vdev->vbasedev.name);
+        }
+    }
+
     vfio_register_err_notifier(vdev);
     vfio_register_req_notifier(vdev);
     vfio_setup_resetfn_quirk(vdev);
@@ -3083,11 +3079,6 @@ out_teardown:
     vfio_bars_exit(vdev);
 error:
     error_prepend(errp, VFIO_MSG_PREFIX, vdev->vbasedev.name);
-    if (vdev->migration_blocker) {
-        migrate_del_blocker(vdev->migration_blocker);
-        error_free(vdev->migration_blocker);
-        vdev->migration_blocker = NULL;
-    }
 }
 
 static void vfio_instance_finalize(Object *obj)
@@ -3099,10 +3090,6 @@ static void vfio_instance_finalize(Object *obj)
     vfio_bars_finalize(vdev);
     g_free(vdev->emulated_config_bits);
     g_free(vdev->rom);
-    if (vdev->migration_blocker) {
-        migrate_del_blocker(vdev->migration_blocker);
-        error_free(vdev->migration_blocker);
-    }
     /*
      * XXX Leaking igd_opregion is not an oversight, we can't remove the
      * fw_cfg entry therefore leaking this allocation seems like the safest
@@ -3130,6 +3117,7 @@ static void vfio_exitfn(PCIDevice *pdev)
     }
     vfio_teardown_msi(vdev);
     vfio_bars_exit(vdev);
+    vfio_migration_finalize(&vdev->vbasedev);
 }
 
 static void vfio_pci_reset(DeviceState *dev)
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index bce71a9ac93f..1574ef983f8f 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -172,7 +172,6 @@ struct VFIOPCIDevice {
     bool no_vfio_ioeventfd;
     bool enable_ramfb;
     VFIODisplay *dpy;
-    Error *migration_blocker;
     Notifier irqchip_change_notifier;
 };