From 94c1d241533397bb938682abeaa51ae74d069cb7 Mon Sep 17 00:00:00 2001
From: Naoki Saito <nasaito@nec.com>
Date: Fri, 17 Jul 2020 17:30:17 +0900
Subject: [PATCH] NEC driver: fix live-migration failure with FC

The initialize_connection() in the driver sometimes returns wrong LUN
and causes a live-migration failure.
The function searches the LUN from LD sets (attached hosts) and returns
the first hit.
The function must return an LUN of the destination host, but the first
hit may be an LUN of the source host.

This patch fixes initialize_connection() to return correct LUN by
searching with WWPN of the desitination host.

Change-Id: I102ae84204e0d88814a7d2e028f7cec118ad6b60
Closes-Bug: #1887908
---
 .../unit/volume/drivers/nec/test_volume.py    | 69 ++++++++++++++++++-
 cinder/volume/drivers/nec/volume_helper.py    |  8 +--
 ...ation-failure-withfc-3128fff7c48e739f.yaml |  6 ++
 3 files changed, 76 insertions(+), 7 deletions(-)
 create mode 100644 releasenotes/notes/bug-1887908-nec-live-migration-failure-withfc-3128fff7c48e739f.yaml

diff --git a/cinder/tests/unit/volume/drivers/nec/test_volume.py b/cinder/tests/unit/volume/drivers/nec/test_volume.py
index 1a93ece3e96..b069c68a448 100644
--- a/cinder/tests/unit/volume/drivers/nec/test_volume.py
+++ b/cinder/tests/unit/volume/drivers/nec/test_volume.py
@@ -211,6 +211,17 @@ xml_out = '''
      <UNIT name="RPL Attribute">IV</UNIT>
     </SECTION>
    </OBJECT>
+   <OBJECT name="Logical Disk">
+    <SECTION name="LD Detail Information">
+     <UNIT name="LDN(h)">0011</UNIT>
+     <UNIT name="OS Type">LX</UNIT>
+     <UNIT name="LD Name">6EWPOChJkdSysJmpMAB9YR</UNIT>
+     <UNIT name="LD Capacity">6442450944</UNIT>
+     <UNIT name="Pool No.(h)">0001</UNIT>
+     <UNIT name="Purpose">---</UNIT>
+     <UNIT name="RPL Attribute">IV</UNIT>
+    </SECTION>
+   </OBJECT>
    <OBJECT name="Logical Disk">
     <SECTION name="LD Detail Information">
      <UNIT name="LDN(h)">0fff</UNIT>
@@ -331,6 +342,26 @@ xml_out = '''
      <UNIT name="LUN(h)">0001</UNIT>
      <UNIT name="LDN(h)">0006</UNIT>
     </SECTION>
+    <SECTION name="LUN/LD List">
+     <UNIT name="LUN(h)">0002</UNIT>
+     <UNIT name="LDN(h)">0011</UNIT>
+    </SECTION>
+   </OBJECT>
+   <OBJECT name="LD Set(FC)">
+    <SECTION name="LD Set(FC) Information">
+     <UNIT name="Platform">LX</UNIT>
+     <UNIT name="LD Set Name">OpenStack3</UNIT>
+    </SECTION>
+    <SECTION name="Path List">
+     <UNIT name="Path">1000-0090-FAA0-786D</UNIT>
+    </SECTION>
+    <SECTION name="Path List">
+     <UNIT name="Path">1000-0090-FAA0-786C</UNIT>
+    </SECTION>
+    <SECTION name="LUN/LD List">
+     <UNIT name="LUN(h)">0001</UNIT>
+     <UNIT name="LDN(h)">0011</UNIT>
+    </SECTION>
    </OBJECT>
    <OBJECT name="LD Set(iSCSI)">
     <SECTION name="LD Set(iSCSI) Information">
@@ -1033,6 +1064,37 @@ class ExportTest(volume_helper.MStorageDSVDriver, test.TestCase):
             self._fc_terminate_connection(vol, connector)
             delldsetld_mock.assert_not_called()
 
+        vol = fake_volume_obj(ctx, id='ccd662e5-2efe-4899-b12f-114b5cad81c3')
+        connector = {'wwpns': ["10000090FAA0786A", "10000090FAA0786B"],
+                     'host': 'HostA'}
+        atchmnt = {
+            'id': constants.ATTACHMENT_ID,
+            'volume_id': vol.id,
+            'connector': connector
+        }
+        attach_object = volume_attachment.VolumeAttachment(**atchmnt)
+        attachment = volume_attachment.VolumeAttachmentList(
+            objects=[attach_object])
+        vol.volume_attachment = attachment
+
+        info = self._fc_initialize_connection(vol, connector)
+        self.assertEqual(2, info['data']['target_lun'])
+
+        connector = {'wwpns': ["10000090FAA0786C", "10000090FAA0786D"],
+                     'host': 'HostB'}
+        atchmnt = {
+            'id': constants.ATTACHMENT_ID,
+            'volume_id': vol.id,
+            'connector': connector
+        }
+        attach_object = volume_attachment.VolumeAttachment(**atchmnt)
+        attachment = volume_attachment.VolumeAttachmentList(
+            objects=[attach_object])
+        vol.volume_attachment = attachment
+
+        info = self._fc_initialize_connection(vol, connector)
+        self.assertEqual(1, info['data']['target_lun'])
+
     def test_fc_terminate_connection(self):
         ctx = context.RequestContext('admin', 'fake', True)
         vol = fake_volume_obj(ctx, id='46045673-41e7-44a7-9333-02f07feab04b')
@@ -1244,7 +1306,12 @@ class NonDisruptiveBackup_test(volume_helper.MStorageDSVDriver,
                       'protocol': 'FC',
                       'wwpn': ['1000-0090-FAA0-786A', '1000-0090-FAA0-786B'],
                       'port': []}
-        return_ldset = [ldset_lds0, ldset_lds1]
+        ldset_lds2 = {'ldsetname': 'LX:OpenStack1',
+                      'lds': {6: {'ldn': 6, 'lun': 1}},
+                      'protocol': 'FC',
+                      'wwpn': ['1000-0090-FAA0-786A', '1000-0090-FAA0-786B'],
+                      'port': []}
+        return_ldset = [ldset_lds0, ldset_lds1, ldset_lds2]
         self.mock_object(self, '_validate_fcldset_exist',
                          side_effect=return_ldset)
         mocker = self.mock_object(self._cli, 'addldsetld',
diff --git a/cinder/volume/drivers/nec/volume_helper.py b/cinder/volume/drivers/nec/volume_helper.py
index 05a374a59f7..dd60f7bf89c 100644
--- a/cinder/volume/drivers/nec/volume_helper.py
+++ b/cinder/volume/drivers/nec/volume_helper.py
@@ -1275,15 +1275,11 @@ class MStorageDriver(volume_common.MStorageVolumeCommon):
         else:
             ldn = lds[ldname]['ldn']
 
-        lun = None
-        for ldset in ldsets.values():
-            if ldn in ldset['lds']:
-                lun = ldset['lds'][ldn]['lun']
-                break
+        ldset = self._validate_fcldset_exist(ldsets, connector)
 
         info = {
             'driver_volume_type': 'fibre_channel',
-            'data': {'target_lun': lun,
+            'data': {'target_lun': ldset['lds'][ldn]['lun'],
                      'target_wwn': target_wwns,
                      'initiator_target_map': init_targ_map}}
 
diff --git a/releasenotes/notes/bug-1887908-nec-live-migration-failure-withfc-3128fff7c48e739f.yaml b/releasenotes/notes/bug-1887908-nec-live-migration-failure-withfc-3128fff7c48e739f.yaml
new file mode 100644
index 00000000000..34fce49ff5e
--- /dev/null
+++ b/releasenotes/notes/bug-1887908-nec-live-migration-failure-withfc-3128fff7c48e739f.yaml
@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    `Bug #1887908 <https://bugs.launchpad.net/cinder/+bug/1887908>`_：
+    In NEC driver, fix live-migration failure with FC.
+