Add snap reserve config option to NetApp cDOT driver

By default, Data ONTAP sets the snapshot reserve for a share to
5%.  Some users have requested a facility to override the default
for applications where snapshots aren't required. This commit adds
a config option for setting a different snap reserve value for a
specific cDOT backend.

Change-Id: Iba0bf696035353fac87f445f690bb94fa00ae0a0
Implements: blueprint netapp-cdot-snap-reserve-config-option

manila/share/drivers/netapp/dataontap/client/client_cmode.py

@@ -1131,7 +1131,8 @@ class NetAppCmodeClient(client_base.NetAppBaseClient):
     def create_volume(self, aggregate_name, volume_name, size_gb,
                       thin_provisioned=False, snapshot_policy=None,
                       language=None, dedup_enabled=False,
-                      compression_enabled=False, max_files=None):
+                      compression_enabled=False, max_files=None,
+                      snapshot_reserve=None):
 
         """Creates a volume."""
         api_args = {
@@ -1146,6 +1147,9 @@ class NetAppCmodeClient(client_base.NetAppBaseClient):
             api_args['snapshot-policy'] = snapshot_policy
         if language is not None:
             api_args['language-code'] = language
+        if snapshot_reserve is not None:
+            api_args['percentage-snapshot-reserve'] = six.text_type(
+                snapshot_reserve)
         self.send_request('volume-create', api_args)
 
         # cDOT compression requires that deduplication be enabled.

manila/share/drivers/netapp/dataontap/cluster_mode/lib_base.py

@@ -383,9 +383,10 @@ class NetAppCmodeFileStorageLibrary(object):
                   'provisioning options %(options)s',
                   {'share': share_name, 'pool': pool_name,
                    'options': provisioning_options})
-        vserver_client.create_volume(pool_name, share_name,
-                                     share['size'],
-                                     **provisioning_options)
+        vserver_client.create_volume(
+            pool_name, share_name, share['size'],
+            snapshot_reserve=self.configuration.
+            netapp_volume_snapshot_reserve_percent, **provisioning_options)
 
     @na_utils.trace
     def _remap_standard_boolean_extra_specs(self, extra_specs):

manila/share/drivers/netapp/options.py

@@ -83,7 +83,13 @@ netapp_provisioning_opts = [
     cfg.StrOpt('netapp_root_volume',
                deprecated_name='netapp_root_volume_name',
                default='root',
-               help='Root volume name.'), ]
+               help='Root volume name.'),
+    cfg.IntOpt('netapp_volume_snapshot_reserve_percent',
+               min=0,
+               max=90,
+               default=5,
+               help='The percentage of share space set aside as reserve for '
+                    'snapshot usage; valid values range from 0 to 90.'), ]
 
 netapp_cluster_opts = [
     cfg.StrOpt('netapp_vserver',

manila/tests/share/drivers/netapp/dataontap/client/test_client_cmode.py

@@ -2055,7 +2055,7 @@ class NetAppClientCmodeTestCase(test.TestCase):
             fake.SHARE_AGGREGATE_NAME, fake.SHARE_NAME, 100,
             thin_provisioned=True, language='en-US',
             snapshot_policy='default', dedup_enabled=True,
-            compression_enabled=True, max_files=5000)
+            compression_enabled=True, max_files=5000, snapshot_reserve=15)
 
         volume_create_args = {
             'containing-aggr-name': fake.SHARE_AGGREGATE_NAME,
@@ -2065,6 +2065,7 @@ class NetAppClientCmodeTestCase(test.TestCase):
             'space-reserve': 'none',
             'language-code': 'en-US',
             'snapshot-policy': 'default',
+            'percentage-snapshot-reserve': '15',
         }
 
         self.client.send_request.assert_called_with('volume-create',

manila/tests/share/drivers/netapp/dataontap/cluster_mode/test_lib_base.py

@@ -569,7 +569,7 @@ class NetAppFileStorageLibraryTestCase(test.TestCase):
             fake.POOL_NAME, fake.SHARE_NAME, fake.SHARE['size'],
             thin_provisioned=True, snapshot_policy='default',
             language='en-US', dedup_enabled=True,
-            compression_enabled=False, max_files=5000)
+            compression_enabled=False, max_files=5000, snapshot_reserve=8)
         mock_remap_standard_boolean_extra_specs.assert_called_once_with(
             fake.EXTRA_SPEC)
 

manila/tests/share/drivers/netapp/dataontap/fakes.py

@@ -511,4 +511,5 @@ def get_config_cmode():
     config.netapp_root_volume_aggregate = ROOT_VOLUME_AGGREGATE
     config.netapp_root_volume = ROOT_VOLUME
     config.netapp_lif_name_template = LIF_NAME_TEMPLATE
+    config.netapp_volume_snapshot_reserve_percent = 8
     return config