vfio: register container for cpr

Define entry points to perform per-container cpr-specific initialization
and teardown.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>

hw/vfio/container.c

@@ -621,10 +621,15 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
         goto free_container_exit;
     }
 
+    ret = vfio_cpr_register_container(bcontainer, errp);
+    if (ret) {
+        goto free_container_exit;
+    }
+
     ret = vfio_ram_block_discard_disable(container, true);
     if (ret) {
         error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken");
-        goto free_container_exit;
+        goto unregister_container_exit;
     }
 
     assert(bcontainer->ops->setup);
@@ -667,6 +672,9 @@ listener_release_exit:
 enable_discards_exit:
     vfio_ram_block_discard_disable(container, false);
 
+unregister_container_exit:
+    vfio_cpr_unregister_container(bcontainer);
+
 free_container_exit:
     g_free(container);
 
@@ -710,6 +718,7 @@ static void vfio_disconnect_container(VFIOGroup *group)
         vfio_container_destroy(bcontainer);
 
         trace_vfio_disconnect_container(container->fd);
+        vfio_cpr_unregister_container(bcontainer);
         close(container->fd);
         g_free(container);
 

hw/vfio/cpr.c

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2021-2024 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/vfio/vfio-common.h"
+#include "qapi/error.h"
+
+int vfio_cpr_register_container(VFIOContainerBase *bcontainer, Error **errp)
+{
+    return 0;
+}
+
+void vfio_cpr_unregister_container(VFIOContainerBase *bcontainer)
+{
+}

hw/vfio/iommufd.c

@@ -411,6 +411,11 @@ found_container:
         goto err_listener_register;
     }
 
+    ret = vfio_cpr_register_container(bcontainer, errp);
+    if (ret) {
+        goto err_listener_register;
+    }
+
     /*
      * TODO: examine RAM_BLOCK_DISCARD stuff, should we do group level
      * for discarding incompatibility check as well?
@@ -461,6 +466,7 @@ static void iommufd_cdev_detach(VFIODevice *vbasedev)
         iommufd_cdev_ram_block_discard_disable(false);
     }
 
+    vfio_cpr_unregister_container(bcontainer);
     iommufd_cdev_detach_container(vbasedev, container);
     iommufd_cdev_container_destroy(container);
     vfio_put_address_space(space);

hw/vfio/meson.build

@@ -5,6 +5,7 @@ vfio_ss.add(files(
   'container-base.c',
   'container.c',
   'migration.c',
+  'cpr.c',
 ))
 vfio_ss.add(when: 'CONFIG_PSERIES', if_true: files('spapr.c'))
 vfio_ss.add(when: 'CONFIG_IOMMUFD', if_true: files(

include/hw/vfio/vfio-common.h

@@ -205,6 +205,9 @@ void vfio_detach_device(VFIODevice *vbasedev);
 int vfio_kvm_device_add_fd(int fd, Error **errp);
 int vfio_kvm_device_del_fd(int fd, Error **errp);
 
+int vfio_cpr_register_container(VFIOContainerBase *bcontainer, Error **errp);
+void vfio_cpr_unregister_container(VFIOContainerBase *bcontainer);
+
 extern const MemoryRegionOps vfio_region_ops;
 typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
 typedef QLIST_HEAD(VFIODeviceList, VFIODevice) VFIODeviceList;