Support Huawei driver upgrade from grizzly to havana

To make the driver upgrade from grizzly to higher versions, the patch
checks the old host name firstly when creating and deleting host in
Huawei storage system.
If the old host name exists:
*get and use it directly when adding host.
*delete it directly when deleting host.

Closes-bug 1237189

Change-Id: I82a9dbc1ef0bb0b91771afea4aadec5afe65eecf

cinder/volume/drivers/huawei/huawei_t.py

@@ -106,7 +106,8 @@ def initialize_connection(self, volume, connector):
             self._get_iscsi_params(connector['initiator'])
 
         # First, add a host if not added before.
-        host_id = self.common.add_host(connector['host'])
+        host_id = self.common.add_host(connector['host'],
+                                       connector['initiator'])
 
         # Then, add the iSCSI port to the host.
         self._add_iscsi_port_to_host(host_id, connector)
@@ -324,7 +325,8 @@ def terminate_connection(self, volume, connector, **kwargs):
 
         self.common._update_login_info()
         host_id = self.common.remove_map(volume['provider_location'],
-                                         connector['host'])
+                                         connector['host'],
+                                         connector['initiator'])
         if not self.common._get_host_map_info(host_id):
             self._remove_iscsi_port(host_id, connector)
 

cinder/volume/drivers/huawei/ssh_common.py

@@ -892,7 +892,7 @@ def map_volume(self, host_id, volume_id):
 
         return hostlun_id
 
-    def add_host(self, host_name):
+    def add_host(self, host_name, initiator=None):
         """Create a host and add it to hostgroup."""
         # Create an OpenStack hostgroup if not created before.
         hostgroup_name = HOST_GROUP_NAME
@@ -902,6 +902,14 @@ def add_host(self, host_name):
             self.hostgroup_id = self._get_hostgroup_id(hostgroup_name)
 
         # Create a host and add it to the hostgroup.
+        # Check the old host name to support the upgrade from grizzly to
+        # higher versions.
+        if initiator:
+            old_host_name = HOST_NAME_PREFIX + str(hash(initiator))
+            old_host_id = self._get_host_id(old_host_name, self.hostgroup_id)
+            if old_host_id is not None:
+                return old_host_id
+
         host_name = HOST_NAME_PREFIX + host_name
         host_id = self._get_host_id(host_name, self.hostgroup_id)
         if host_id is None:
@@ -1003,13 +1011,20 @@ def change_lun_ctr(self, lun_id, ctr):
                                      'LUN %s' % lun_id,
                                      cli_cmd, out)
 
-    def remove_map(self, volume_id, host_name):
+    def remove_map(self, volume_id, host_name, initiator=None):
         """Remove host map."""
-        host_name = HOST_NAME_PREFIX + host_name
-        host_id = self._get_host_id(host_name, self.hostgroup_id)
+        # Check the old host name to support the upgrade from grizzly to
+        # higher versions.
+        host_id = None
+        if initiator:
+            old_host_name = HOST_NAME_PREFIX + str(hash(initiator))
+            host_id = self._get_host_id(old_host_name, self.hostgroup_id)
         if host_id is None:
-            LOG.error(_('remove_map: Host %s does not exist.') % host_name)
-            raise exception.HostNotFound(host=host_name)
+            host_name = HOST_NAME_PREFIX + host_name
+            host_id = self._get_host_id(host_name, self.hostgroup_id)
+            if host_id is None:
+                LOG.error(_('remove_map: Host %s does not exist.') % host_name)
+                raise exception.HostNotFound(host=host_name)
 
         if not self._check_volume_created(volume_id):
             LOG.error(_('remove_map: Volume %s does not exist.') % volume_id)