Reject live migration and suspend on SEV guests

As per the spec[0], live migration and suspend are not (yet) supported
for SEV guests, so reject them at the API level with an HTTP
409 (Conflict).

[0] http://specs.openstack.org/openstack/nova-specs/specs/train/approved/amd-sev-libvirt-support.html#limitations

blueprint: amd-sev-libvirt-support
Change-Id: I69b6e153324a3e5680e096cd714e5d4dd05bae34

nova/api/openstack/compute/migrate_server.py

@@ -171,6 +171,8 @@ class MigrateServerController(wsgi.Controller):
                               "'%(ex)s'", {'ex': ex})
             else:
                 raise exc.HTTPBadRequest(explanation=ex.format_message())
+        except exception.OperationNotSupportedForSEV as e:
+            raise exc.HTTPConflict(explanation=e.format_message())
         except exception.InstanceIsLocked as e:
             raise exc.HTTPConflict(explanation=e.format_message())
         except exception.ComputeHostNotFound as e:

nova/api/openstack/compute/suspend_server.py

@@ -38,7 +38,8 @@ class SuspendServerController(wsgi.Controller):
                         target={'user_id': server.user_id,
                                 'project_id': server.project_id})
             self.compute_api.suspend(context, server)
-        except exception.InstanceIsLocked as e:
+        except (exception.OperationNotSupportedForSEV,
+                exception.InstanceIsLocked) as e:
             raise exc.HTTPConflict(explanation=e.format_message())
         except exception.InstanceInvalidState as state_error:
             common.raise_http_conflict_for_instance_invalid_state(state_error,

nova/compute/api.py

@@ -205,6 +205,24 @@ def check_instance_lock(function):
     return inner
 
 
+def reject_sev_instances(operation):
+    """Decorator.  Raise OperationNotSupportedForSEV if instance has SEV
+    enabled.
+    """
+
+    def outer(f):
+        @six.wraps(f)
+        def inner(self, context, instance, *args, **kw):
+            if hardware.get_mem_encryption_constraint(instance.flavor,
+                                                      instance.image_meta):
+                raise exception.OperationNotSupportedForSEV(
+                    instance_uuid=instance.uuid,
+                    operation=operation)
+            return f(self, context, instance, *args, **kw)
+        return inner
+    return outer
+
+
 def _diff_dict(orig, new):
     """Return a dict describing how to change orig to new.  The keys
     correspond to values that have changed; the value will be a list
@@ -3785,6 +3803,7 @@ class API(base.Base):
         return self.compute_rpcapi.get_instance_diagnostics(context,
                                                             instance=instance)
 
+    @reject_sev_instances(instance_actions.SUSPEND)
     @check_instance_lock
     @check_instance_state(vm_state=[vm_states.ACTIVE])
     def suspend(self, context, instance):
@@ -4448,6 +4467,7 @@ class API(base.Base):
                                                      diff=diff)
         return _metadata
 
+    @reject_sev_instances(instance_actions.LIVE_MIGRATION)
     @check_instance_lock
     @check_instance_state(vm_state=[vm_states.ACTIVE, vm_states.PAUSED])
     def live_migrate(self, context, instance, block_migration,

nova/exception.py

@@ -533,6 +533,12 @@ class UnableToMigrateToSelf(Invalid):
                 "to current host (%(host)s).")
 
 
+class OperationNotSupportedForSEV(NovaException):
+    msg_fmt = _("Operation '%(operation)s' not supported for SEV-enabled "
+                "instance (%(instance_uuid)s).")
+    code = 409
+
+
 class InvalidHypervisorType(Invalid):
     msg_fmt = _("The supplied hypervisor type of is invalid.")
 

nova/tests/unit/api/openstack/compute/test_migrate_server.py

@@ -609,6 +609,20 @@ class MigrateServerTestsV268(MigrateServerTestsV256):
                            method_translations=method_translations,
                            args_map=args_map)
 
+    @mock.patch('nova.virt.hardware.get_mem_encryption_constraint',
+                new=mock.Mock(return_value=True))
+    @mock.patch.object(objects.instance.Instance, 'image_meta')
+    def test_live_migrate_sev_rejected(self, mock_image):
+        instance = self._stub_instance_get()
+        body = {'os-migrateLive': {'host': 'hostname',
+                                   'block_migration': 'auto'}}
+        ex = self.assertRaises(webob.exc.HTTPConflict,
+                               self.controller._migrate_live,
+                               self.req, fakes.FAKE_UUID, body=body)
+        self.assertIn("Operation 'live-migration' not supported for "
+                      "SEV-enabled instance (%s)" % instance.uuid,
+                      six.text_type(ex))
+
     def test_live_migrate_with_forced_host(self):
         body = {'os-migrateLive': {'host': 'hostname',
                                    'block_migration': 'auto',

nova/tests/unit/api/openstack/compute/test_suspend_server.py

@@ -13,10 +13,13 @@
 #    under the License.
 
 import mock
+import six
+import webob
 
 from nova.api.openstack.compute import suspend_server as \
     suspend_server_v21
 from nova import exception
+from nova import objects
 from nova import test
 from nova.tests.unit.api.openstack.compute import admin_only_action_common
 from nova.tests.unit.api.openstack import fakes
@@ -39,6 +42,17 @@ class SuspendServerTestsV21(admin_only_action_common.CommonTests):
     def test_suspend_resume(self):
         self._test_actions(['_suspend', '_resume'])
 
+    @mock.patch('nova.virt.hardware.get_mem_encryption_constraint',
+                new=mock.Mock(return_value=True))
+    @mock.patch.object(objects.instance.Instance, 'image_meta')
+    def test_suspend_sev_rejected(self, mock_image):
+        instance = self._stub_instance_get()
+        ex = self.assertRaises(webob.exc.HTTPConflict,
+                               self.controller._suspend,
+                               self.req, fakes.FAKE_UUID, body={})
+        self.assertIn("Operation 'suspend' not supported for SEV-enabled "
+                      "instance (%s)" % instance.uuid, six.text_type(ex))
+
     def test_suspend_resume_with_non_existed_instance(self):
         self._test_actions_with_non_existed_instance(['_suspend', '_resume'])