Reject resize operation for accelerator

When resize with a new flavor with accelerator, we should raise
forbidden exception to reject the resize operation.
Add related unit test.
Follow up the comment:
https://review.opendev.org/#/c/715326/22/nova/compute/api.py@3907

Conflicts:
  nova/compute/api.py
  nova/tests/unit/compute/test_compute_api.py

NOTE(brinzhang): Conflicts are due to change
eef4b5435e7cdfe53ee9d9265d96c7dd278d9e93 ("api: Reject
non-spawn operations for vTPM") which modified the same code.

Add 'extra_specs={}' as a request parameter in test_resize_quota_check()
in nova/tests/unit/compute/test_compute_api.py. Actually this change is
required due to not having patch
I147bf4d95e6d86ff1f967a8ce37260730f21d236 in stable ussuri.

Co-Authored-By: Wenping Song <songwenping@inspur.com>

Closes-Bug: #1893751

Change-Id: Ie20a620588e3b0d18055c34ec7671e91e6bf6ee0
(cherry picked from commit 97267fc05c60b60761ebe8ec2773e8920148ae06)

2 files changed, 26 insertions, 1 deletions

diff --git a/nova/compute/api.py b/nova/compute/api.py
index 2b9ae0f982..0ec92174ec 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -3875,6 +3875,12 @@ class API(base.Base):
         else:
             new_instance_type = flavors.get_flavor_by_flavor_id(
                     flavor_id, read_deleted="no")
+            # NOTE(wenping): We use this instead of the 'block_accelerator'
+            # decorator since the operation can differ depending on args,
+            # and for resize we have two flavors to worry about, we should
+            # reject resize with new flavor with accelerator.
+            if new_instance_type.extra_specs.get('accel:device_profile'):
+                raise exception.ForbiddenWithAccelerators()
             # Check to see if we're resizing to a zero-disk flavor which is
             # only supported with volume-backed servers.
             if (new_instance_type.get('root_gb') == 0 and
diff --git a/nova/tests/unit/compute/test_compute_api.py b/nova/tests/unit/compute/test_compute_api.py
index 624fdf2d74..c7515fedfc 100644
--- a/nova/tests/unit/compute/test_compute_api.py
+++ b/nova/tests/unit/compute/test_compute_api.py
@@ -2063,7 +2063,7 @@ class _ComputeAPIUnitTestMixIn(object):
         fake_inst = self._create_instance_obj()
         fake_inst.flavor = cur_flavor
         new_flavor = objects.Flavor(id=2, name='bar', vcpus=1, memory_mb=2048,
-                                    root_gb=10, disabled=False)
+                                    root_gb=10, disabled=False, extra_specs={})
         mock_get.return_value = new_flavor
         mock_check.side_effect = exception.OverQuota(
                 overs=['ram'], quotas={'cores': 1, 'ram': 2048},
@@ -2078,6 +2078,25 @@ class _ComputeAPIUnitTestMixIn(object):
                 project_values={'cores': 1, 'ram': 2560},
                 project_id=fake_inst.project_id, user_id=fake_inst.user_id)
 
+    @mock.patch('nova.compute.api.API.get_instance_host_status',
+                new=mock.Mock(return_value=fields_obj.HostStatus.UP))
+    @mock.patch('nova.compute.utils.is_volume_backed_instance',
+                new=mock.Mock(return_value=False))
+    @mock.patch.object(flavors, 'get_flavor_by_flavor_id')
+    def test_resize__with_accelerator(self, mock_get_flavor):
+        """Ensure resizes are rejected if either flavor requests accelerator.
+        """
+        fake_inst = self._create_instance_obj()
+        new_flavor = self._create_flavor(
+            id=200, flavorid='new-flavor-id', name='new_flavor',
+            disabled=False, extra_specs={'accel:device_profile': 'dp'})
+        mock_get_flavor.return_value = new_flavor
+
+        self.assertRaises(
+            exception.ForbiddenWithAccelerators,
+            self.compute_api.resize,
+            self.context, fake_inst, flavor_id=new_flavor.flavorid)
+
     def test_migrate(self):
         self._test_migrate()