Return iSCSI Initiator for VIOSes

Adding the get_iscsi_initiators method in iscsi volume adapter
to discover all iSCSI initiators for active VIOSes and return
the first initiator from the sorted collection of initiators.

Change-Id: Ic842bd49e0a3dc6e4f4a3bf14409ca2f70369a26

nova_powervm/tests/virt/powervm/test_driver.py

@@ -1,4 +1,4 @@
-# Copyright 2014, 2017 IBM Corp.
+# Copyright 2014, 2018 IBM Corp.
 #
 # All Rights Reserved.
 #
@@ -15,7 +15,7 @@
 #    under the License.
 
 from __future__ import absolute_import
-
+import collections
 import fixtures
 import logging
 import mock
@@ -206,21 +206,21 @@ class TestPowerVMDriver(test.NoDBTestCase):
         self.assertTrue(
             self.drv.session.get_event_listener.return_value.shutdown.called)
 
-    @mock.patch('nova_powervm.virt.powervm.volume.get_iscsi_initiator',
+    @mock.patch('nova_powervm.virt.powervm.volume.iscsi.get_iscsi_initiators')
-                autospec=True)
+    def test_get_volume_connector(self, mock_initiators):
-    def test_get_volume_connector(self, mock_initiator):
         """Tests that a volume connector can be built."""
-        mock_initiator.return_value = 'iscsi_initiator'
+
+        initiators = [('1300C76F-9814-4A4D-B1F0-5B69352A7DEA', 'fake_iqn1'),
+                      ('7DBBE705-E4C4-4458-8223-3EBE07015CA9', 'fake_iqn2')]
+        initiators = collections.OrderedDict(initiators)
+
+        mock_initiators.return_value = initiators
 
         self.flags(volume_adapter='fibre_channel', group='powervm')
         vol_connector = self.drv.get_volume_connector(mock.Mock())
         self.assertIsNotNone(vol_connector['wwpns'])
         self.assertIsNotNone(vol_connector['host'])
-        self.assertEqual('iscsi_initiator', vol_connector['initiator'])
+        self.assertEqual('fake_iqn1', vol_connector['initiator'])
-
-        self.flags(volume_adapter='iscsi', group='powervm')
-        vol_connector = self.drv.get_volume_connector(mock.Mock())
-        self.assertEqual('iscsi_initiator', vol_connector['initiator'])
 
     def test_setup_disk_adapter(self):
         # Ensure we can handle upper case option and we instantiate the class

nova_powervm/tests/virt/powervm/volume/test_driver.py

@@ -1,4 +1,4 @@
-# Copyright 2015, 2017 IBM Corp.
+# Copyright 2015, 2018 IBM Corp.
 #
 # All Rights Reserved.
 #
@@ -15,7 +15,6 @@
 #    under the License.
 
 import mock
-from pypowervm.wrappers import virtual_io_server as pvm_vios
 import six
 
 from nova import test
@@ -54,34 +53,6 @@ class TestInitMethods(test.NoDBTestCase):
         'gpfs': gpfs.GPFSVolumeAdapter,
     }
 
-    @mock.patch('pypowervm.tasks.hdisk.discover_iscsi_initiator')
-    @mock.patch('pypowervm.tasks.partition.get_mgmt_partition')
-    def test_get_iscsi_initiator(self, mock_mgmt, mock_iscsi_init):
-        # Set up mocks and clear out data that may have been set by other
-        # tests
-        mock_adpt = mock.Mock()
-        mock_mgmt.return_value = mock.Mock(spec=pvm_vios.VIOS)
-        mock_iscsi_init.return_value = 'test_initiator'
-
-        self.assertEqual('test_initiator',
-                         volume.get_iscsi_initiator(mock_adpt))
-
-        # Make sure it gets set properly in the backend
-        self.assertEqual('test_initiator', volume._ISCSI_INITIATOR)
-        self.assertTrue(volume._ISCSI_LOOKUP_COMPLETE)
-        mock_mgmt.assert_called_once_with(mock_adpt)
-        self.assertEqual(1, mock_mgmt.call_count)
-
-        # Invoke again, make sure it doesn't call down to the mgmt part again
-        self.assertEqual('test_initiator',
-                         volume.get_iscsi_initiator(mock_adpt))
-        self.assertEqual(1, mock_mgmt.call_count)
-
-        # Check if initiator returned does not have newline character
-        mock_iscsi_init.return_value = 'test_initiator\n'
-        self.assertEqual('test_initiator',
-                         volume.get_iscsi_initiator(mock_adpt))
-
     def test_get_volume_class(self):
         for vol_type, class_type in six.iteritems(self.volume_drivers):
             self.assertEqual(class_type, volume.get_volume_class(vol_type))

nova_powervm/tests/virt/powervm/volume/test_iscsi.py

@@ -392,3 +392,64 @@ class TestISCSIAdapter(test_vol.TestVolumeAdapter):
         retrieved_devname = self.vol_drv._get_devname()
         # Check key not found
         self.assertIsNone(retrieved_devname)
+
+    @mock.patch('pypowervm.tasks.partition.get_active_vioses')
+    @mock.patch('pypowervm.tasks.hdisk.discover_iscsi_initiator')
+    def test_get_iscsi_initiators(self, mock_iscsi_init, mock_active_vioses):
+        # Set up mocks and clear out data that may have been set by other
+        # tests
+        iscsi._ISCSI_INITIATORS = dict()
+        mock_iscsi_init.return_value = 'test_initiator'
+
+        vios_ids = ['1300C76F-9814-4A4D-B1F0-5B69352A7DEA',
+                    '7DBBE705-E4C4-4458-8223-3EBE07015CA9']
+
+        mock_active_vioses.return_value = vios_ids
+
+        expected_output = {
+            '1300C76F-9814-4A4D-B1F0-5B69352A7DEA': 'test_initiator',
+            '7DBBE705-E4C4-4458-8223-3EBE07015CA9': 'test_initiator'
+        }
+
+        self.assertEqual(expected_output,
+                         iscsi.get_iscsi_initiators(self.adpt, vios_ids))
+
+        # Make sure it gets set properly in the backend
+        self.assertEqual(expected_output, iscsi._ISCSI_INITIATORS)
+        self.assertEqual(mock_active_vioses.call_count, 0)
+        self.assertEqual(mock_iscsi_init.call_count, 2)
+
+        # Invoke again, make sure it doesn't call down to the mgmt part again
+        mock_iscsi_init.reset_mock()
+        self.assertEqual(expected_output,
+                         iscsi.get_iscsi_initiators(self.adpt, vios_ids))
+        self.assertEqual(mock_active_vioses.call_count, 0)
+        self.assertEqual(mock_iscsi_init.call_count, 0)
+
+        # Invoke iscsi.get_iscsi_initiators with vios_id=None
+        iscsi._ISCSI_INITIATORS = dict()
+        mock_iscsi_init.reset_mock()
+        self.assertEqual(expected_output,
+                         iscsi.get_iscsi_initiators(self.adpt, None))
+        self.assertEqual(expected_output, iscsi._ISCSI_INITIATORS)
+        self.assertEqual(mock_active_vioses.call_count, 1)
+        self.assertEqual(mock_iscsi_init.call_count, 2)
+
+        # Invoke again with vios_id=None to ensure get_active_vioses,
+        # discover_iscsi_initiator is not called
+        mock_iscsi_init.reset_mock()
+        mock_active_vioses.reset_mock()
+        self.assertEqual(expected_output,
+                         iscsi.get_iscsi_initiators(self.adpt, None))
+        self.assertEqual(mock_active_vioses.call_count, 0)
+        self.assertEqual(mock_iscsi_init.call_count, 0)
+
+        # Invoke iscsi.get_iscsi_initiators with discover_iscsi_initiator()
+        # raises ISCSIDiscoveryFailed exception
+        iscsi._ISCSI_INITIATORS = dict()
+        mock_iscsi_init.reset_mock()
+        mock_iscsi_init.side_effect = pvm_exc.ISCSIDiscoveryFailed(
+            vios_uuid='fake_vios_uid', status="fake_status")
+        self.assertEqual(dict(),
+                         iscsi.get_iscsi_initiators(self.adpt, vios_ids))
+        self.assertEqual(dict(), iscsi._ISCSI_INITIATORS)

nova_powervm/virt/powervm/driver.py

@@ -1,4 +1,4 @@
-# Copyright 2014, 2017 IBM Corp.
+# Copyright 2014, 2018 IBM Corp.
 #
 # All Rights Reserved.
 #
@@ -66,7 +66,7 @@ from nova_powervm.virt.powervm.tasks import storage as tf_stg
 from nova_powervm.virt.powervm.tasks import vm as tf_vm
 from nova_powervm.virt.powervm import vm
 from nova_powervm.virt.powervm import volume as vol_attach
-
+from nova_powervm.virt.powervm.volume import iscsi
 
 LOG = logging.getLogger(__name__)
 CONF = cfg.CONF
@@ -1103,7 +1103,9 @@ class PowerVMDriver(driver.ComputeDriver):
             connector["wwpns"] = wwpn_list
         connector["multipath"] = CONF.powervm.volume_use_multipath
         connector['host'] = vol_attach.get_hostname_for_volume(instance)
-        connector['initiator'] = vol_attach.get_iscsi_initiator(self.adapter)
+        initiator_dict = iscsi.get_iscsi_initiators(self.adapter)
+        if initiator_dict:
+            connector['initiator'] = list(initiator_dict.values())[0]
         return connector
 
     def migrate_disk_and_power_off(self, context, instance, dest,

nova_powervm/virt/powervm/volume/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2015, 2017 IBM Corp.
+# Copyright 2015, 2018 IBM Corp.
 #
 # All Rights Reserved.
 #
@@ -14,11 +14,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from oslo_concurrency import lockutils
-from pypowervm.tasks import hdisk
-from pypowervm.tasks import partition
-from pypowervm.wrappers import virtual_io_server as pvm_vios
-
 
 # Defines the various volume connectors that can be used.
 from nova import exception
@@ -85,28 +80,3 @@ def get_wwpns_for_volume_connector(adapter, host_uuid, instance):
     fc_vol_drv = build_volume_driver(adapter, host_uuid, instance,
                                      fake_fc_conn_info)
     return fc_vol_drv.wwpns()
-
-
-_ISCSI_INITIATOR = None
-_ISCSI_LOOKUP_COMPLETE = False
-
-
-@lockutils.synchronized("PowerVM_iSCSI_Initiator_Lookup")
-def get_iscsi_initiator(adapter):
-    """Gets the iSCSI initiator.
-
-    This is looked up once at process start up.  Stored in memory thereafter.
-
-    :param adapter: The pypowervm adapter.
-    :return: The initiator name.  If the NovaLink is not capable of supporting
-             iSCSI, None will be returned.
-    """
-    global _ISCSI_INITIATOR, _ISCSI_LOOKUP_COMPLETE
-    if not _ISCSI_LOOKUP_COMPLETE:
-        mgmt_w = partition.get_mgmt_partition(adapter)
-        if isinstance(mgmt_w, pvm_vios.VIOS):
-            _ISCSI_INITIATOR = hdisk.discover_iscsi_initiator(
-                adapter, mgmt_w.uuid).strip()
-
-    _ISCSI_LOOKUP_COMPLETE = True
-    return _ISCSI_INITIATOR

nova_powervm/virt/powervm/volume/iscsi.py

@@ -13,6 +13,7 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
+import collections
 import copy
 from oslo_concurrency import lockutils
 from oslo_log import log as logging
@@ -26,6 +27,7 @@ from nova_powervm.virt.powervm.volume import volume
 from pypowervm import const as pvm_const
 from pypowervm import exceptions as pvm_exc
 from pypowervm.tasks import hdisk
+from pypowervm.tasks import partition as pvm_partition
 from pypowervm.utils import transaction as tx
 from pypowervm.wrappers import virtual_io_server as pvm_vios
 
@@ -37,6 +39,56 @@ import six
 LOG = logging.getLogger(__name__)
 CONF = cfg.CONF
 DEVNAME_KEY = 'target_devname'
+_ISCSI_INITIATORS = collections.OrderedDict()
+
+
+def get_iscsi_initiators(adapter, vios_ids=None):
+    """Gets the VIOS iSCSI initiators.
+
+     For the first time invocation of this method after process start up,
+     it populates initiators data for VIOSes (if specified, otherwise it
+     gets active VIOSes from the host) and stores in memory for futher
+     lookup.
+
+    :param adapter: The pypowervm adapter
+    :param vios_ids: List of VIOS ids to get the initiators. If not
+                     specified, a list of active VIOSes for the
+                     host is fetched (but only for the first time)
+                     through the pypowervm adapter.
+    :return: A dict of the form
+             {<vios_id>: <list of initiators>}
+    """
+
+    global _ISCSI_INITIATORS
+
+    def discover_initiator(vios_id):
+
+        # Get the VIOS id lock for initiator lookup
+        @lockutils.synchronized('inititator-lookup-' + vios_id)
+        def _discover_initiator():
+            if (vios_id in _ISCSI_INITIATORS and
+                    _ISCSI_INITIATORS[vios_id]):
+                return
+            else:
+                try:
+                    initiator = hdisk.discover_iscsi_initiator(
+                        adapter, vios_id)
+                    _ISCSI_INITIATORS[vios_id] = initiator
+                except pvm_exc.ISCSIDiscoveryFailed as e:
+                    # TODO(chhagarw): handle differently based on
+                    # error codes
+                    LOG.error(e)
+
+        _discover_initiator()
+
+    if vios_ids is None and not _ISCSI_INITIATORS:
+        vios_ids = pvm_partition.get_active_vioses(adapter)
+
+    for vios_id in vios_ids or []:
+        discover_initiator(vios_id)
+
+    LOG.debug("iSCSI initiator info: %s" % _ISCSI_INITIATORS)
+    return _ISCSI_INITIATORS
 
 
 class IscsiVolumeAdapter(volume.VscsiVolumeAdapter,