[VNX] Restore snapshot to volume

Add `revert_to_snapshot` API support for VNX Cinder driver.

Implements: blueprint vnx-revert-to-snapshot

Change-Id: Id6e3090d96a5bbf4879e8577fe3565c3032de228

cinder/tests/unit/volume/drivers/dell_emc/vnx/mocked_cinder.yaml

@@ -207,6 +207,10 @@ test_create_snapshot_adapter:
 test_delete_snapshot_adapter:
   snapshot: *snapshot_base
 
+test_restore_snapshot_adapter:
+  volume: *volume_base
+  snapshot: *snapshot_base
+
 test_do_create_cgsnap: &cg_snap_and_snaps
   cg_snap: *cg_snapshot_base
   snap1: *snapshot_base

cinder/tests/unit/volume/drivers/dell_emc/vnx/mocked_vnx.yaml

@@ -696,6 +696,15 @@ test_modify_snapshot:
     _methods:
       get_snap: *snap_modify
 
+test_restore_snapshot: &test_restore_snapshot
+  lun: &lun_restore
+    _methods:
+      restore_snap:
+
+  vnx:
+    _methods:
+      get_lun: *lun_restore
+
 test_create_cg_snapshot: &test_create_cg_snapshot
   cg_snap: &cg_snap_exist
     _properties:
@@ -1614,6 +1623,8 @@ test_create_snapshot_adapter: *test_create_snapshot
 
 test_delete_snapshot_adapter: *test_delete_snapshot
 
+test_restore_snapshot_adapter: *test_restore_snapshot
+
 test_create_cgsnapshot: *test_create_cg_snapshot
 
 test_do_create_cgsnap: *test_create_cg_snapshot

cinder/tests/unit/volume/drivers/dell_emc/vnx/test_adapter.py

@@ -619,6 +619,13 @@ class TestCommonAdapter(test.TestCase):
                                      mocked_input):
         common_adapter.delete_snapshot(mocked_input['snapshot'])
 
+    @res_mock.mock_driver_input
+    @res_mock.patch_common_adapter
+    def test_restore_snapshot_adapter(self, common_adapter, _ignore,
+                                      mocked_input):
+        common_adapter.restore_snapshot(mocked_input['volume'],
+                                        mocked_input['snapshot'])
+
     @res_mock.patch_common_adapter
     def test_create_cgsnapshot(self, common_adapter, _):
         common_adapter.do_create_cgsnap = mock.Mock(

cinder/tests/unit/volume/drivers/dell_emc/vnx/test_client.py

@@ -309,6 +309,10 @@ class TestClient(test.TestCase):
     def test_modify_snapshot(self, client, mocked):
         client.modify_snapshot('snap_name', True, True)
 
+    @res_mock.patch_client
+    def test_restore_snapshot(self, client, mocked):
+        client.restore_snapshot('lun-id', 'snap_name')
+
     @res_mock.patch_client
     def test_create_cg_snapshot(self, client, mocked):
         snap = client.create_cg_snapshot('cg_snap_name', 'cg_name')

cinder/volume/drivers/dell_emc/vnx/adapter.py

@@ -811,6 +811,11 @@ class CommonAdapter(replication.ReplicationAdapter):
         """Deletes a snapshot."""
         self.client.delete_snapshot(snapshot.name)
 
+    def restore_snapshot(self, volume, snapshot):
+        """Restores a snapshot."""
+        lun_id = self.client.get_lun_id(volume)
+        self.client.restore_snapshot(lun_id, snapshot.name)
+
     def _get_referenced_lun(self, existing_ref):
         lun = None
         if 'source-id' in existing_ref:

cinder/volume/drivers/dell_emc/vnx/client.py

@@ -337,6 +337,10 @@ class Client(object):
         snap.modify(allow_rw=allow_rw, auto_delete=auto_delete,
                     keep_for=None)
 
+    def restore_snapshot(self, lun_id, snap_name):
+        lun = self.get_lun(lun_id=lun_id)
+        lun.restore_snap(snap_name)
+
     def create_consistency_group(self, cg_name, lun_id_list=None):
         try:
             cg = self.vnx.create_cg(name=cg_name, members=lun_id_list)

cinder/volume/drivers/dell_emc/vnx/driver.py

@@ -77,9 +77,10 @@ class VNXDriver(driver.ManageableVD,
           10.1.0 - Add QoS support
           10.2.0 - Add replication group support
           11.0.0 - Fix failure of migration during cloning
+          12.0.0 - Add `volume revert to snapshot` support
     """
 
-    VERSION = '11.00.00'
+    VERSION = '12.00.00'
     VENDOR = 'Dell EMC'
     # ThirdPartySystems wiki page
     CI_WIKI_NAME = "EMC_VNX_CI"
@@ -141,6 +142,10 @@ class VNXDriver(driver.ManageableVD,
         """Deletes a snapshot."""
         self.adapter.delete_snapshot(snapshot)
 
+    def revert_to_snapshot(self, context, volume, snapshot):
+        """Reverts a volume to a snapshot"""
+        self.adapter.restore_snapshot(volume, snapshot)
+
     def ensure_export(self, context, volume):
         """Driver entry point to get the export info for an existing volume."""
         pass

doc/source/configuration/block-storage/drivers/dell-emc-vnx-driver.rst

@@ -39,6 +39,7 @@ Supported operations
 - Create a consistency group from consistency group snapshots.
 - Replication v2.1 support.
 - Generic Group support.
+- Revert a volume to a snapshot.
 
 Preparation
 ~~~~~~~~~~~

driver-requirements.txt

@@ -32,7 +32,7 @@ rados # LGPLv2.1
 rbd # LGPLv2.1
 
 # Dell EMC VNX
-storops>=0.4.8 # Apache-2.0
+storops>=0.5.7 # Apache-2.0
 
 # Violin
 vmemclient>=1.1.8 # Apache-2.0

releasenotes/notes/vnx-revert-to-snapshot-e5494b6fb5ad5a1e.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Added support to revert a volume to a snapshot with the Dell EMC VNX
+    driver.