PowerMax Driver - Fix assign SRP during promotion retype

SRP is not assigned during failover-promotion retype. In cases
where SRP is different between primary and remote arrays this
can lead to issues once failover-promotion is finalized. Fixed
by adding SRP assignment when generating volume's model update.

Change-Id: Id0500c2f85974818fa2a841c9dca77f1fef4df04
Closes-Bug: 1905564
(cherry picked from commit 00ad39a600)

cinder/tests/unit/volume/drivers/dell_emc/powermax/test_powermax_replication.py

@@ -1186,15 +1186,16 @@ class PowerMaxReplicationTest(test.TestCase):
         return_value=(True, tpd.PowerMaxData.defaultstoragegroup_name))
     def test_migrate_volume_success_rep_promotion(
             self, mck_retype, mck_get, mck_break, mck_valid):
-        array_id = self.data.array
+        array_id = self.data.remote_array
         volume = self.data.test_rep_volume
         device_id = self.data.device_id
-        srp = self.data.srp
+        srp = 'SRP_2'
         target_slo = self.data.slo_silver
         target_workload = self.data.workload
         volume_name = volume.name
         new_type = {'extra_specs': {}}
         extra_specs = self.data.rep_extra_specs_rep_config
+        updated_host = 'HostX@Backend#Diamond+DSS+SRP_2+000197800124'
         self.common.promotion = True
         target_extra_specs = {
             utils.SRP: srp, utils.ARRAY: array_id, utils.SLO: target_slo,
@@ -1205,6 +1206,7 @@ class PowerMaxReplicationTest(test.TestCase):
         success, model_update = self.common._migrate_volume(
             array_id, volume, device_id, srp, target_slo, target_workload,
             volume_name, new_type, extra_specs)
+        self.assertEqual(model_update['host'], updated_host)
         mck_break.assert_called_once_with(
             array_id, device_id, volume_name, extra_specs)
         mck_retype.assert_called_once_with(

cinder/volume/drivers/dell_emc/powermax/common.py

@@ -4086,7 +4086,9 @@ class PowerMaxCommon(object):
                     previous_host = volume.get('host')
                     host_details = previous_host.split('+')
                     array_index = len(host_details) - 1
+                    srp_index = len(host_details) - 2
                     host_details[array_index] = array
+                    host_details[srp_index] = srp
                     updated_host = '+'.join(host_details)
                     model_update['host'] = updated_host
 

releasenotes/notes/bug-1905564-e7dcf28fd734d3b2.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    PowerMax Driver `bug #1905564
+    <https://bugs.launchpad.net/cinder/+bug/1905564>`_: Fix
+    Fix remote SRP not being assigned to volume's Host when
+    performing retype during failover-promotion.