Don't change volume's status when create backups from snapshots

when users try to create a backup from a snapshot, the volume
related to the snapshot is set to backing-up during the action
and can't be used for other actions.
When create a backup from a large snapshot, such as larger
than 1 TB, it will cost few hours generally. It's really a
problem that the volume is not available for such a long time.

If the snapshot is provided, we change the status of the snapshot;
otherwise, we change the status of the volume as usual.

This patch added "backing-up" status for snapshot as well

DocImpact

Change-Id: I86d34c470fabbf4132b5e004d9f368e751c893a5
Closes-bug: #1670541

cinder/backup/api.py

@@ -291,7 +291,10 @@ class API(base.Base):
         if snapshot_id:
             snapshot = objects.Snapshot.get_by_id(context, snapshot_id)
             data_timestamp = snapshot.created_at
-
+            self.db.snapshot_update(
+                context, snapshot_id,
+                {'status': fields.SnapshotStatus.BACKING_UP})
+        else:
             self.db.volume_update(context, volume_id,
                                   {'status': 'backing-up',
                                    'previous_status': previous_status})

cinder/backup/manager.py

@@ -355,7 +355,10 @@ class BackupManager(manager.ThreadPoolManager):
     def create_backup(self, context, backup):
         """Create volume backups using configured backup service."""
         volume_id = backup.volume_id
+        snapshot_id = backup.snapshot_id
         volume = objects.Volume.get_by_id(context, volume_id)
+        snapshot = objects.Snapshot.get_by_id(
+            context, snapshot_id) if snapshot_id else None
         previous_status = volume.get('previous_status', None)
         LOG.info('Create backup started, backup: %(backup_id)s '
                  'volume: %(volume_id)s.',
@@ -368,7 +371,7 @@ class BackupManager(manager.ThreadPoolManager):
         backup.availability_zone = self.az
         backup.save()
 
-        expected_status = 'backing-up'
+        expected_status = 'available' if snapshot_id else "backing-up"
         actual_status = volume['status']
         if actual_status != expected_status:
             err = _('Create backup aborted, expected volume status '
@@ -379,6 +382,18 @@ class BackupManager(manager.ThreadPoolManager):
             self._update_backup_error(backup, err)
             raise exception.InvalidVolume(reason=err)
 
+        if snapshot_id:
+            expected_status = fields.SnapshotStatus.BACKING_UP
+            actual_status = snapshot['status']
+            if actual_status != expected_status:
+                err = _('Create backup aborted, expected snapshot status '
+                        '%(expected_status)s but got %(actual_status)s.') % {
+                    'expected_status': expected_status,
+                    'actual_status': actual_status,
+                }
+                self._update_backup_error(backup, err)
+                raise exception.InvalidSnapshot(reason=err)
+
         expected_status = fields.BackupStatus.CREATING
         actual_status = backup.status
         if actual_status != expected_status:
@@ -401,6 +416,10 @@ class BackupManager(manager.ThreadPoolManager):
                 self._update_backup_error(backup, six.text_type(err))
 
         # Restore the original status.
+        if snapshot_id:
+            self.db.snapshot_update(context, snapshot_id,
+                                    {'status': fields.BackupStatus.AVAILABLE})
+        else:
             self.db.volume_update(context, volume_id,
                                   {'status': previous_status,
                                    'previous_status': 'backing-up'})

cinder/objects/base.py

@@ -129,6 +129,7 @@ OBJ_VERSIONS.add('1.21', {'ManageableSnapshot': '1.0',
                           'ManageableVolume': '1.0',
                           'ManageableVolumeList': '1.0',
                           'ManageableSnapshotList': '1.0'})
+OBJ_VERSIONS.add('1.22', {'Snapshot': '1.4'})
 
 
 class CinderObjectRegistry(base.VersionedObjectRegistry):

cinder/objects/fields.py

@@ -123,9 +123,10 @@ class SnapshotStatus(BaseCinderEnum):
     UPDATING = 'updating'
     ERROR_DELETING = 'error_deleting'
     UNMANAGING = 'unmanaging'
+    BACKING_UP = 'backing-up'
 
     ALL = (ERROR, AVAILABLE, CREATING, DELETING, DELETED,
-           UPDATING, ERROR_DELETING, UNMANAGING)
+           UPDATING, ERROR_DELETING, UNMANAGING, BACKING_UP)
 
 
 class SnapshotStatusField(BaseEnumField):

cinder/objects/snapshot.py

@@ -36,7 +36,8 @@ class Snapshot(cleanable.CinderCleanableObject, base.CinderObject,
     # Version 1.1: Changed 'status' field to use SnapshotStatusField
     # Version 1.2: This object is now cleanable (adds rows to workers table)
     # Version 1.3: SnapshotStatusField now includes "unmanaging"
-    VERSION = '1.3'
+    # Version 1.4: SnapshotStatusField now includes "backing-up"
+    VERSION = '1.4'
 
     # NOTE(thangp): OPTIONAL_FIELDS are fields that would be lazy-loaded. They
     # are typically the relationship in the sqlalchemy object.
@@ -121,6 +122,9 @@ class Snapshot(cleanable.CinderCleanableObject, base.CinderObject,
         if target_version < (1, 3):
             if primitive.get('status') == c_fields.SnapshotStatus.UNMANAGING:
                 primitive['status'] = c_fields.SnapshotStatus.DELETING
+        if target_version < (1, 4):
+            if primitive.get('status') == c_fields.SnapshotStatus.BACKING_UP:
+                primitive['status'] = c_fields.SnapshotStatus.AVAILABLE
 
     @classmethod
     def _from_db_object(cls, context, snapshot, db_snapshot,

cinder/tests/unit/backup/test_backup.py

@@ -78,7 +78,8 @@ class BaseBackupTest(test.TestCase):
                                 project_id=str(uuid.uuid4()),
                                 service=None,
                                 temp_volume_id=None,
-                                temp_snapshot_id=None):
+                                temp_snapshot_id=None,
+                                snapshot_id=None):
         """Create a backup entry in the DB.
 
         Return the entry ID
@@ -96,7 +97,7 @@ class BaseBackupTest(test.TestCase):
         kwargs['status'] = status
         kwargs['fail_reason'] = ''
         kwargs['service'] = service or CONF.backup_driver
-        kwargs['snapshot'] = False
+        kwargs['snapshot_id'] = snapshot_id
         kwargs['parent_id'] = None
         kwargs['size'] = size
         kwargs['object_count'] = object_count
@@ -618,6 +619,28 @@ class BackupTestCase(BaseBackupTest):
         self.assertEqual(fields.BackupStatus.AVAILABLE, backup['status'])
         self.assertEqual(vol_size, backup['size'])
 
+    @mock.patch('cinder.backup.manager.BackupManager._run_backup')
+    @ddt.data(fields.SnapshotStatus.BACKING_UP,
+              fields.SnapshotStatus.AVAILABLE)
+    def test_create_backup_with_snapshot(self, snapshot_status,
+                                         mock_run_backup):
+        vol_id = self._create_volume_db_entry(status='available')
+        snapshot = self._create_snapshot_db_entry(volume_id=vol_id,
+                                                  status=snapshot_status)
+        backup = self._create_backup_db_entry(volume_id=vol_id,
+                                              snapshot_id=snapshot.id)
+        if snapshot_status == fields.SnapshotStatus.BACKING_UP:
+            self.backup_mgr.create_backup(self.ctxt, backup)
+
+            vol = objects.Volume.get_by_id(self.ctxt, vol_id)
+            snapshot = objects.Snapshot.get_by_id(self.ctxt, snapshot.id)
+
+            self.assertEqual('available', vol.status)
+            self.assertEqual(fields.SnapshotStatus.AVAILABLE, snapshot.status)
+        else:
+            self.assertRaises(exception.InvalidSnapshot,
+                              self.backup_mgr.create_backup, self.ctxt, backup)
+
     @mock.patch('cinder.utils.brick_get_connector_properties')
     @mock.patch('cinder.volume.rpcapi.VolumeAPI.get_backup_device')
     @mock.patch('cinder.utils.temporary_chown')
@@ -1495,6 +1518,32 @@ class BackupAPITestCase(BaseBackupTest):
         backup = self.api.create(self.ctxt, None, None, volume_id, None)
         self.assertEqual('testhost', backup.host)
 
+    @mock.patch.object(api.API, '_get_available_backup_service_host',
+                       return_value='fake_host')
+    @mock.patch('cinder.backup.rpcapi.BackupAPI.create_backup')
+    @ddt.data(True, False)
+    def test_create_backup_resource_status(self, is_snapshot, mock_create,
+                                           mock_get_service):
+        self.ctxt.user_id = 'fake_user'
+        self.ctxt.project_id = 'fake_project'
+        volume_id = self._create_volume_db_entry(status='available')
+        snapshot = self._create_snapshot_db_entry(volume_id=volume_id)
+        if is_snapshot:
+            self.api.create(self.ctxt, None, None, volume_id, None,
+                            snapshot_id=snapshot.id)
+            volume = objects.Volume.get_by_id(self.ctxt, volume_id)
+            snapshot = objects.Snapshot.get_by_id(self.ctxt, snapshot.id)
+
+            self.assertEqual('backing-up', snapshot.status)
+            self.assertEqual('available', volume.status)
+        else:
+            self.api.create(self.ctxt, None, None, volume_id, None)
+            volume = objects.Volume.get_by_id(self.ctxt, volume_id)
+            snapshot = objects.Snapshot.get_by_id(self.ctxt, snapshot.id)
+
+            self.assertEqual('available', snapshot.status)
+            self.assertEqual('backing-up', volume.status)
+
     @mock.patch('cinder.backup.api.API._get_available_backup_service_host')
     @mock.patch('cinder.backup.rpcapi.BackupAPI.restore_backup')
     def test_restore_volume(self,

cinder/tests/unit/objects/test_objects.py

@@ -43,7 +43,7 @@ object_data = {
     'RequestSpec': '1.1-b0bd1a28d191d75648901fa853e8a733',
     'Service': '1.4-c7d011989d1718ca0496ccf640b42712',
     'ServiceList': '1.1-15ecf022a68ddbb8c2a6739cfc9f8f5e',
-    'Snapshot': '1.3-69dfbe3244992478a0174cb512cd7f27',
+    'Snapshot': '1.4-b7aa184837ccff570b8443bfd1773017',
     'SnapshotList': '1.0-15ecf022a68ddbb8c2a6739cfc9f8f5e',
     'Volume': '1.6-7d3bc8577839d5725670d55e480fe95f',
     'VolumeList': '1.1-15ecf022a68ddbb8c2a6739cfc9f8f5e',

cinder/tests/unit/objects/test_snapshot.py

@@ -231,7 +231,7 @@ class TestSnapshot(test_objects.BaseObjectsTestCase):
                       fake.SNAPSHOT_ID)])
 
     @ddt.data('1.1', '1.3')
-    def test_obj_make_compatible(self, version):
+    def test_obj_make_compatible_1_3(self, version):
         snapshot = objects.Snapshot(context=self.context)
         snapshot.status = 'unmanaging'
         primitive = snapshot.obj_to_primitive(version)
@@ -242,6 +242,18 @@ class TestSnapshot(test_objects.BaseObjectsTestCase):
             status = fields.SnapshotStatus.DELETING
         self.assertEqual(status, snapshot.status)
 
+    @ddt.data('1.3', '1.4')
+    def test_obj_make_compatible_1_4(self, version):
+        snapshot = objects.Snapshot(context=self.context)
+        snapshot.status = fields.SnapshotStatus.BACKING_UP
+        primitive = snapshot.obj_to_primitive(version)
+        snapshot = objects.Snapshot.obj_from_primitive(primitive)
+        if version == '1.4':
+            status = fields.SnapshotStatus.BACKING_UP
+        else:
+            status = fields.SnapshotStatus.AVAILABLE
+        self.assertEqual(status, snapshot.status)
+
 
 class TestSnapshotList(test_objects.BaseObjectsTestCase):
     @mock.patch('cinder.objects.volume.Volume.get_by_id')

releasenotes/notes/snapshot_backing_up_status_support-164fbbb2a564e137.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - Fix the unreasonable status change for volumes and snapshots when creating
+    backups from snapshots.
+upgrade:
+  - The "backing-up" status is added to snapshot's status matrix.