Fix volume retype with migration as non-admin

As a non-admin user, when retyping a volume from type
A -> B, where both types are in different backends,
Cinder will complete the operation but the volumes will
 not be migrated.

This happens because the retype operation relies in
getting the extra_specs information to the related type,
but extra_specs is only avaiable in admin context.

Closes-bug: #1657806
Change-Id: Id9f39ddab3a3648b8721b711ecf78c18c8293451

cinder/tests/unit/volume/__init__.py

@@ -58,6 +58,9 @@ class BaseVolumeTestCase(test.TestCase):
         # assertions with the notification code, it's part of an
         # elastic-recheck query so don't remove it or change it.
         self.project_id = '7f265bd4-3a85-465e-a899-5dc4854a86d3'
+        self.user_context = context.RequestContext(user_id=fake.USER_ID,
+                                                   project_id=self.project_id,
+                                                   is_admin=False)
         self.context.project_id = self.project_id
         self.volume_params = {
             'status': 'creating',

cinder/tests/unit/volume/test_volume_migration.py

@@ -53,8 +53,8 @@ def create_snapshot(volume_id, size=1, metadata=None, ctxt=None,
     metadata = metadata or {}
     snap = objects.Snapshot(ctxt or context.get_admin_context())
     snap.volume_size = size
-    snap.user_id = fake.USER_ID
-    snap.project_id = fake.PROJECT_ID
+    snap.user_id = kwargs.get('user_id', fake.USER_ID)
+    snap.project_id = kwargs.get('project_id', fake.PROJECT_ID)
     snap.volume_id = volume_id
     snap.status = "creating"
     if metadata is not None:
@@ -710,7 +710,10 @@ class VolumeMigrationTestCase(base.BaseVolumeTestCase):
         volume.previous_status = 'available'
         volume.save()
         if snap:
-            create_snapshot(volume.id, size=volume.size)
+            create_snapshot(volume.id, size=volume.size,
+                            user_id=self.user_context.user_id,
+                            project_id=self.user_context.project_id,
+                            ctxt=self.user_context)
         if driver or diff_equal:
             host_obj = {'host': CONF.host, 'capabilities': {}}
         else:
@@ -746,9 +749,11 @@ class VolumeMigrationTestCase(base.BaseVolumeTestCase):
         with mock.patch.object(self.volume.driver, 'retype') as _retype,\
                 mock.patch.object(volume_types, 'volume_types_diff') as _diff,\
                 mock.patch.object(self.volume, 'migrate_volume') as _mig,\
-                mock.patch.object(db.sqlalchemy.api, 'volume_get') as mock_get:
-            mock_get.return_value = volume
+                mock.patch.object(db.sqlalchemy.api, 'volume_get') as _vget,\
+                mock.patch.object(context.RequestContext, 'elevated') as _ctx:
+            _vget.return_value = volume
             _retype.return_value = driver
+            _ctx.return_value = self.context
             returned_diff = {
                 'encryption': {},
                 'qos_specs': {},

cinder/volume/manager.py

@@ -2305,10 +2305,11 @@ class VolumeManager(manager.CleanableManager,
         # We already got the new reservations
         new_reservations = reservations
 
-        # If volume types have the same contents, no need to do anything
+        # If volume types have the same contents, no need to do anything.
+        # Use the admin contex to be able to access volume extra_specs
         retyped = False
         diff, all_equal = volume_types.volume_types_diff(
-            context, volume.volume_type_id, new_type_id)
+            context.elevated(), volume.volume_type_id, new_type_id)
         if all_equal:
             retyped = True
 
@@ -2328,12 +2329,14 @@ class VolumeManager(manager.CleanableManager,
                 not diff.get('encryption') and
                 self._is_our_backend(host['host'], host.get('cluster_name'))):
             try:
-                new_type = volume_types.get_volume_type(context, new_type_id)
-                ret = self.driver.retype(context,
-                                         volume,
-                                         new_type,
-                                         diff,
-                                         host)
+                new_type = volume_types.get_volume_type(context.elevated(),
+                                                        new_type_id)
+                with volume.obj_as_admin():
+                    ret = self.driver.retype(context,
+                                             volume,
+                                             new_type,
+                                             diff,
+                                             host)
                 # Check if the driver retype provided a model update or
                 # just a retype indication
                 if type(ret) == tuple: