Storwize: add backup snapshots support

This patch adds backup snapshots support for Storwize/SVC driver.
The change implements attach and detach snapshot:
initialize_connection_snapshot
terminate_connection_snapshot

Implements: blueprint storwize-backup-snapshots

Change-Id: I65393a6a5f995d609152d4b8546c055d7bf0b253

cinder/tests/unit/volume/drivers/ibm/test_storwize_svc.py

@@ -2758,6 +2758,12 @@ class StorwizeSVCISCSIDriverTestCase(test.TestCase):
         vol = testutils.create_volume(self.ctxt, **prop)
         return vol
 
+    def _generate_snap_info(self, vol_id, size=10):
+        prop = {'volume_id': vol_id,
+                'volume_size': size}
+        snap = testutils.create_snapshot(self.ctxt, **prop)
+        return snap
+
     def _assert_vol_exists(self, name, exists):
         is_vol_defined = self.iscsi_driver._helpers.is_vdisk_defined(name)
         self.assertEqual(exists, is_vol_defined)
@@ -2797,6 +2803,43 @@ class StorwizeSVCISCSIDriverTestCase(test.TestCase):
         self.iscsi_driver.initialize_connection(volume_iSCSI, connector)
         self.iscsi_driver.terminate_connection(volume_iSCSI, connector)
 
+    def test_storwize_iscsi_connection_snapshot(self):
+        # create a iSCSI volume
+        volume_iSCSI = self._create_volume()
+        snapshot = self._generate_snap_info(volume_iSCSI.id)
+        self.iscsi_driver.create_snapshot(snapshot)
+        connector = {'host': 'storwize-svc-host',
+                     'wwnns': ['20000090fa17311e', '20000090fa17311f'],
+                     'wwpns': ['ff00000000000000', 'ff00000000000001'],
+                     'initiator': 'iqn.1993-08.org.debian:01:eac5ccc1aaa'}
+
+        self.iscsi_driver.initialize_connection_snapshot(snapshot, connector)
+        self.iscsi_driver.terminate_connection_snapshot(snapshot, connector)
+
+    def test_storwize_replication_failover_iscsi_connection_snapshot(self):
+        volume_iSCSI = self._create_volume()
+        snapshot = self._generate_snap_info(volume_iSCSI.id)
+        self.iscsi_driver.create_snapshot(snapshot)
+        connector = {'host': 'storwize-svc-host',
+                     'wwnns': ['20000090fa17311e', '20000090fa17311f'],
+                     'wwpns': ['ff00000000000000', 'ff00000000000001'],
+                     'initiator': 'iqn.1993-08.org.debian:01:eac5ccc1aaa'}
+        # a snapshot of a replication failover volume. attach will be failed
+        with mock.patch.object(storwize_svc_common.StorwizeSVCCommonDriver,
+                               '_get_volume_replicated_type') as rep_type:
+            rep_type.return_value = True
+            with mock.patch.object(storwize_svc_common.StorwizeSVCCommonDriver,
+                                   '_get_vol_sys_info') as sys_info:
+                sys_info.return_value = {'volume_name': 'voliscsi',
+                                         'backend_helper':
+                                             'self._aux_backend_helpers',
+                                         'node_state': 'self._state'}
+                self.assertRaises(exception.VolumeDriverException,
+                                  self.iscsi_driver.
+                                  initialize_connection_snapshot,
+                                  snapshot,
+                                  connector)
+
     @mock.patch.object(storwize_svc_iscsi.StorwizeSVCISCSIDriver,
                        '_do_terminate_connection')
     @mock.patch.object(storwize_svc_iscsi.StorwizeSVCISCSIDriver,
@@ -3298,6 +3341,12 @@ class StorwizeSVCFcDriverTestCase(test.TestCase):
         vol = testutils.create_volume(self.ctxt, **prop)
         return vol
 
+    def _generate_snap_info(self, vol_id, size=10):
+        prop = {'volume_id': vol_id,
+                'volume_size': size}
+        snap = testutils.create_snapshot(self.ctxt, **prop)
+        return snap
+
     def _assert_vol_exists(self, name, exists):
         is_vol_defined = self.fc_driver._helpers.is_vdisk_defined(name)
         self.assertEqual(exists, is_vol_defined)
@@ -3315,6 +3364,44 @@ class StorwizeSVCFcDriverTestCase(test.TestCase):
 
         self.assertIsNotNone(host_name)
 
+    def test_storwize_fc_connection_snapshot(self):
+        # create a iSCSI volume
+        volume_fc = self._create_volume()
+        snapshot = self._generate_snap_info(volume_fc.id)
+        self.fc_driver.create_snapshot(snapshot)
+        connector = {'host': 'storwize-svc-host',
+                     'wwnns': ['20000090fa17311e', '20000090fa17311f'],
+                     'wwpns': ['ff00000000000000', 'ff00000000000001'],
+                     'initiator': 'iqn.1993-08.org.debian:01:eac5ccc1aaa'}
+
+        self.fc_driver.initialize_connection_snapshot(snapshot, connector)
+        self.fc_driver.terminate_connection_snapshot(snapshot, connector)
+
+    def test_storwize_replication_failover_fc_connection_snapshot(self):
+        volume_fc = self._create_volume()
+        volume_fc['replication_status'] = fields.ReplicationStatus.FAILED_OVER
+        snapshot = self._generate_snap_info(volume_fc.id)
+        self.fc_driver.create_snapshot(snapshot)
+        connector = {'host': 'storwize-svc-host',
+                     'wwnns': ['20000090fa17311e', '20000090fa17311f'],
+                     'wwpns': ['ff00000000000000', 'ff00000000000001'],
+                     'initiator': 'iqn.1993-08.org.debian:01:eac5ccc1aaa'}
+        # a snapshot of a replication failover volume. attach will be failed
+        with mock.patch.object(storwize_svc_common.StorwizeSVCCommonDriver,
+                               '_get_volume_replicated_type') as rep_type:
+            rep_type.return_value = True
+            with mock.patch.object(storwize_svc_common.StorwizeSVCCommonDriver,
+                                   '_get_vol_sys_info') as sys_info:
+                sys_info.return_value = {'volume_name': 'volfc',
+                                         'backend_helper':
+                                             'self._aux_backend_helpers',
+                                         'node_state': 'self._state'}
+                self.assertRaises(exception.VolumeDriverException,
+                                  self.fc_driver.
+                                  initialize_connection_snapshot,
+                                  snapshot,
+                                  connector)
+
     def test_storwize_get_host_with_fc_connection_with_volume(self):
         # create a FC volume
         volume_fc = self._generate_vol_info(None, None)

cinder/volume/drivers/ibm/storwize_svc/storwize_svc_common.py

@@ -2578,6 +2578,13 @@ class StorwizeSVCCommonDriver(san.SanDriver,
     def remove_export(self, ctxt, volume):
         pass
 
+    def create_export_snapshot(self, ctxt, snapshot, connector):
+        model_update = None
+        return model_update
+
+    def remove_export_snapshot(self, ctxt, snapshot):
+        pass
+
     def _get_vdisk_params(self, type_id, volume_type=None,
                           volume_metadata=None):
         return self._helpers.get_vdisk_params(self.configuration,
@@ -3860,6 +3867,21 @@ class StorwizeSVCCommonDriver(san.SanDriver,
 
         return tgt_vol, backend_helper, node_state
 
+    def _check_snapshot_replica_volume_status(self, snapshot):
+        ctxt = context.get_admin_context()
+        if self._get_volume_replicated_type(ctxt, None,
+                                            snapshot.volume_type_id):
+            LOG.debug('It is a replication volume snapshot for backup.')
+            rep_volume = objects.Volume.get_by_id(ctxt, snapshot.volume_id)
+            volume_name, backend_helper, node_state = self._get_vol_sys_info(
+                rep_volume)
+            if backend_helper != self._helpers or self._active_backend_id:
+                msg = (_('The snapshot of the replication volume %s has '
+                         'failed over to the aux backend. It can not attach'
+                         ' to the aux backend.') % volume_name)
+                LOG.error(msg)
+                raise exception.VolumeDriverException(message=msg)
+
     def migrate_volume(self, ctxt, volume, host):
         """Migrate directly if source and dest are managed by same storage.
 

cinder/volume/drivers/ibm/storwize_svc/storwize_svc_fc.py

@@ -33,6 +33,7 @@ localized format.
 are of different sizes, is not supported.
 
 """
+import collections
 
 from oslo_config import cfg
 from oslo_log import log as logging
@@ -93,6 +94,7 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
         2.2.1 - Add vdisk mirror/stretch cluster support
         2.2.2 - Add npiv support
         2.2.3 - Add replication group support
+        2.2.4 - Add backup snapshots support
     """
 
     VERSION = "2.2.3"
@@ -114,6 +116,21 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
             raise exception.InvalidConnectorException(
                 missing='wwpns')
 
+    def initialize_connection_snapshot(self, snapshot, connector):
+        """Perform attach snapshot for backup snapshots."""
+        # If the snapshot's source volume is a replication volume and the
+        # replication volume has failed over to aux_backend,
+        # attach the snapshot will be failed.
+        self._check_snapshot_replica_volume_status(snapshot)
+
+        vol_attrs = ['id', 'name', 'display_name']
+        Volume = collections.namedtuple('Volume', vol_attrs)
+        volume = Volume(id=snapshot.id,
+                        name=snapshot.name,
+                        display_name='backup-snapshot')
+
+        return self.initialize_connection(volume, connector)
+
     @fczm_utils.add_fc_zone
     def initialize_connection(self, volume, connector):
         """Perform necessary work to make a FC connection."""
@@ -136,9 +153,16 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
 
         """
         LOG.debug('enter: initialize_connection: volume %(vol)s with connector'
-                  ' %(conn)s', {'vol': volume['id'], 'conn': connector})
+                  ' %(conn)s', {'vol': volume.id, 'conn': connector})
-        volume_name, backend_helper, node_state = self._get_vol_sys_info(
+        if volume.display_name == 'backup-snapshot':
-            volume)
+            LOG.debug('It is a virtual volume %(vol)s for attach snapshot.',
+                      {'vol': volume.id})
+            volume_name = volume.name
+            backend_helper = self._helpers
+            node_state = self._state
+        else:
+            volume_name, backend_helper, node_state = self._get_vol_sys_info(
+                volume)
 
         # Check if a host object is defined for this host name
         host_name = backend_helper.get_host_from_connector(connector)
@@ -192,7 +216,7 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
             properties = {}
             properties['target_discovered'] = False
             properties['target_lun'] = lun_id
-            properties['volume_id'] = volume['id']
+            properties['volume_id'] = volume.id
 
             conn_wwpns = backend_helper.get_conn_fc_wwpns(host_name)
 
@@ -234,7 +258,7 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
 
         LOG.debug('leave: initialize_connection:\n volume: %(vol)s\n '
                   'connector %(conn)s\n properties: %(prop)s',
-                  {'vol': volume['id'], 'conn': connector,
+                  {'vol': volume.id, 'conn': connector,
                    'prop': properties})
 
         return {'driver_volume_type': 'fibre_channel', 'data': properties, }
@@ -249,6 +273,16 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
 
         return i_t_map
 
+    def terminate_connection_snapshot(self, snapshot, connector, **kwargs):
+        """Perform detach snapshot for backup snapshots."""
+        vol_attrs = ['id', 'name', 'display_name']
+        Volume = collections.namedtuple('Volume', vol_attrs)
+        volume = Volume(id=snapshot.id,
+                        name=snapshot.name,
+                        display_name='backup-snapshot')
+
+        return self.terminate_connection(volume, connector, **kwargs)
+
     @fczm_utils.remove_fc_zone
     def terminate_connection(self, volume, connector, **kwargs):
         """Cleanup after an FC connection has been terminated."""
@@ -276,8 +310,16 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
            automatically by this driver when mappings are created)
         """
         LOG.debug('enter: terminate_connection: volume %(vol)s with connector'
-                  ' %(conn)s', {'vol': volume['id'], 'conn': connector})
+                  ' %(conn)s', {'vol': volume.id, 'conn': connector})
-        vol_name, backend_helper, node_state = self._get_vol_sys_info(volume)
+        if volume.display_name == 'backup-snapshot':
+            LOG.debug('It is a virtual volume %(vol)s for detach snapshot.',
+                      {'vol': volume.id})
+            vol_name = volume.name
+            backend_helper = self._helpers
+            node_state = self._state
+        else:
+            vol_name, backend_helper, node_state = self._get_vol_sys_info(
+                volume)
 
         info = {}
         if 'host' in connector:
@@ -324,6 +366,6 @@ class StorwizeSVCFCDriver(storwize_common.StorwizeSVCCommonDriver):
                 backend_helper.delete_host(host_name)
 
         LOG.debug('leave: terminate_connection: volume %(vol)s with '
-                  'connector %(conn)s', {'vol': volume['id'],
+                  'connector %(conn)s', {'vol': volume.id,
                                          'conn': connector})
         return info

cinder/volume/drivers/ibm/storwize_svc/storwize_svc_iscsi.py

@@ -33,6 +33,7 @@ localized format.
 are of different sizes, is not supported.
 
 """
+import collections
 
 from oslo_config import cfg
 from oslo_log import log as logging
@@ -92,6 +93,7 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
         2.2 - Add CG capability to generic volume groups
         2.2.1 - Add vdisk mirror/stretch cluster support
         2.2.2 - Add replication group support
+        2.2.3 - Add backup snapshots support
     """
 
     VERSION = "2.2.2"
@@ -113,6 +115,21 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
             raise exception.InvalidConnectorException(
                 missing='initiator')
 
+    def initialize_connection_snapshot(self, snapshot, connector):
+        """Perform attach snapshot for backup snapshots."""
+        # If the snapshot's source volume is a replication volume and the
+        # replication volume has failed over to aux_backend,
+        # attach the snapshot will be failed.
+        self._check_snapshot_replica_volume_status(snapshot)
+
+        vol_attrs = ['id', 'name', 'display_name']
+        Volume = collections.namedtuple('Volume', vol_attrs)
+        volume = Volume(id=snapshot.id,
+                        name=snapshot.name,
+                        display_name='backup-snapshot')
+
+        return self.initialize_connection(volume, connector)
+
     def initialize_connection(self, volume, connector):
         """Perform necessary work to make an iSCSI connection."""
         @utils.synchronized('storwize-host' + self._state['system_id'] +
@@ -133,9 +150,16 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
         proper I/O group)
         """
         LOG.debug('enter: initialize_connection: volume %(vol)s with connector'
-                  ' %(conn)s', {'vol': volume['id'], 'conn': connector})
+                  ' %(conn)s', {'vol': volume.id, 'conn': connector})
-        volume_name, backend_helper, node_state = self._get_vol_sys_info(
+        if volume.display_name == 'backup-snapshot':
-            volume)
+            LOG.debug('It is a virtual volume %(vol)s for attach snapshot.',
+                      {'vol': volume.id})
+            volume_name = volume.name
+            backend_helper = self._helpers
+            node_state = self._state
+        else:
+            volume_name, backend_helper, node_state = self._get_vol_sys_info(
+                volume)
 
         # Check if a host object is defined for this host name
         host_name = backend_helper.get_host_from_connector(connector,
@@ -178,7 +202,7 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
 
         LOG.debug('leave: initialize_connection:\n volume: %(vol)s\n '
                   'connector: %(conn)s\n properties: %(prop)s',
-                  {'vol': volume['id'], 'conn': connector,
+                  {'vol': volume.id, 'conn': connector,
                    'prop': properties})
 
         return {'driver_volume_type': 'iscsi', 'data': properties, }
@@ -186,11 +210,19 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
     def _get_single_iscsi_data(self, volume, connector, lun_id, chap_secret):
         LOG.debug('enter: _get_single_iscsi_data: volume %(vol)s with '
                   'connector %(conn)s lun_id %(lun_id)s',
-                  {'vol': volume['id'], 'conn': connector,
+                  {'vol': volume.id, 'conn': connector,
                    'lun_id': lun_id})
 
-        volume_name, backend_helper, node_state = self._get_vol_sys_info(
+        if volume.display_name == 'backup-snapshot':
-            volume)
+            LOG.debug('It is a virtual volume %(vol)s for attach snapshot',
+                      {'vol': volume.name})
+            volume_name = volume.name
+            backend_helper = self._helpers
+            node_state = self._state
+        else:
+            volume_name, backend_helper, node_state = self._get_vol_sys_info(
+                volume)
+
         volume_attributes = backend_helper.get_vdisk_attributes(volume_name)
         if volume_attributes is None:
             msg = (_('_get_single_iscsi_data: Failed to get attributes'
@@ -311,6 +343,16 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
 
         return properties
 
+    def terminate_connection_snapshot(self, snapshot, connector, **kwargs):
+        """Perform detach snapshot for backup snapshots."""
+        vol_attrs = ['id', 'name', 'display_name']
+        Volume = collections.namedtuple('Volume', vol_attrs)
+        volume = Volume(id=snapshot.id,
+                        name=snapshot.name,
+                        display_name='backup-snapshot')
+
+        return self.terminate_connection(volume, connector, **kwargs)
+
     def terminate_connection(self, volume, connector, **kwargs):
         """Cleanup after an iSCSI connection has been terminated."""
         # If a fake connector is generated by nova when the host
@@ -337,8 +379,16 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
         automatically by this driver when mappings are created)
         """
         LOG.debug('enter: terminate_connection: volume %(vol)s with connector'
-                  ' %(conn)s', {'vol': volume['id'], 'conn': connector})
+                  ' %(conn)s', {'vol': volume.id, 'conn': connector})
-        vol_name, backend_helper, node_state = self._get_vol_sys_info(volume)
+        if volume.display_name == 'backup-snapshot':
+            LOG.debug('It is a virtual volume %(vol)s for detach snapshot.',
+                      {'vol': volume.id})
+            vol_name = volume.name
+            backend_helper = self._helpers
+            node_state = self._state
+        else:
+            vol_name, backend_helper, node_state = self._get_vol_sys_info(
+                volume)
 
         info = {}
         if 'host' in connector:
@@ -366,6 +416,6 @@ class StorwizeSVCISCSIDriver(storwize_common.StorwizeSVCCommonDriver):
                 backend_helper.delete_host(host_name)
 
         LOG.debug('leave: terminate_connection: volume %(vol)s with '
-                  'connector %(conn)s', {'vol': volume['id'],
+                  'connector %(conn)s', {'vol': volume.id,
                                          'conn': connector})
         return info

releasenotes/notes/storwize-backup-snapshot-support-728e18dfa0d42943.yaml

@@ -0,0 +1,3 @@
+---
+features:
+  - Add backup snapshots support for Storwize/SVC driver.