Use volume driver specific exceptions

Change generic use of exception.NovaException in the nova/volume directory
to specific exceptions. The exceptions used in this patch are:

 exception.VolumeBackendAPIException
 exception.InvalidInput
 exception.InvalidVolume
 exception.VolumeAtatched

Patch includes updates to the appropriate tests as well.

(cherry picked from cinder commit 3905a99)

Change-Id: I10407ff3f5babe64e88f445d3529269b7665ee16

6 files changed, 108 insertions, 90 deletions

diff --git a/nova/volume/driver.py b/nova/volume/driver.py
index d03ad7cdc..8aa7fd595 100644
--- a/nova/volume/driver.py
+++ b/nova/volume/driver.py
@@ -104,8 +104,9 @@ class VolumeDriver(object):
                                 run_as_root=True)
         volume_groups = out.split()
         if not FLAGS.volume_group in volume_groups:
-            raise exception.NovaException(_("volume group %s doesn't exist")
+            exception_message = (_("volume group %s doesn't exist")
                                   % FLAGS.volume_group)
+            raise exception.VolumeBackendAPIException(data=exception_message)
 
     def _create_volume(self, volume_name, sizestr):
         self._try_execute('lvcreate', '-L', sizestr, '-n',
@@ -429,9 +430,9 @@ class ISCSIDriver(VolumeDriver):
             location = self._do_iscsi_discovery(volume)
 
             if not location:
-                raise exception.NovaException(_("Could not find iSCSI export "
-                                        " for volume %s") %
-                                      (volume['name']))
+                raise exception.InvalidVolume(_("Could not find iSCSI export "
+                                                " for volume %s") %
+                                              (volume['name']))
 
             LOG.debug(_("ISCSI Discovery: Found %s") % (location))
             properties['target_discovered'] = True
@@ -563,8 +564,9 @@ class RBDDriver(VolumeDriver):
         (stdout, stderr) = self._execute('rados', 'lspools')
         pools = stdout.split("\n")
         if not FLAGS.rbd_pool in pools:
-            raise exception.NovaException(_("rbd has no pool %s") %
-                                  FLAGS.rbd_pool)
+            exception_message = (_("rbd has no pool %s") %
+                                    FLAGS.rbd_pool)
+            raise exception.VolumeBackendAPIException(data=exception_message)
 
     def create_volume(self, volume):
         """Creates a logical volume."""
@@ -641,10 +643,13 @@ class SheepdogDriver(VolumeDriver):
             #  use it and just check if 'running' is in the output.
             (out, err) = self._execute('collie', 'cluster', 'info')
             if not 'running' in out.split():
-                msg = _("Sheepdog is not working: %s") % out
-                raise exception.NovaException(msg)
+                exception_message = _("Sheepdog is not working: %s") % out
+                raise exception.VolumeBackendAPIException(
+                                                data=exception_message)
+
         except exception.ProcessExecutionError:
-            raise exception.NovaException(_("Sheepdog is not working"))
+            exception_message = _("Sheepdog is not working")
+            raise exception.NovaException(data=exception_message)
 
     def create_volume(self, volume):
         """Creates a sheepdog volume"""
diff --git a/nova/volume/manager.py b/nova/volume/manager.py
index a45ae0d65..eed73e212 100644
--- a/nova/volume/manager.py
+++ b/nova/volume/manager.py
@@ -164,10 +164,11 @@ class VolumeManager(manager.SchedulerDependentManager):
         context = context.elevated()
         volume_ref = self.db.volume_get(context, volume_id)
         if volume_ref['attach_status'] == "attached":
-            raise exception.NovaException(_("Volume is still attached"))
+            # Volume is still attached, need to detach first
+            raise exception.VolumeAttached(volume_id=volume_id)
         if volume_ref['host'] != self.host:
-            msg = _("Volume is not local to this node")
-            raise exception.NovaException(msg)
+            raise exception.InvalidVolume(
+                reason=_("Volume is not local to this node"))
 
         self._notify_about_volume_usage(context, volume_ref, "delete.start")
         self._reset_stats()
diff --git a/nova/volume/netapp.py b/nova/volume/netapp.py
index 6dd5c0e31..1d0c574c7 100644
--- a/nova/volume/netapp.py
+++ b/nova/volume/netapp.py
@@ -106,7 +106,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
             name = request.Name
             reason = response.Reason
             msg = _('API %(name)s failed: %(reason)s')
-            raise exception.NovaException(msg % locals())
+            raise exception.VolumeBackendAPIException(data=msg % locals())
 
     def _create_client(self, **kwargs):
         """Instantiate a web services client.
@@ -151,11 +151,12 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
                 'netapp_server_hostname', 'netapp_server_port']
         for flag in required_flags:
             if not getattr(FLAGS, flag, None):
-                raise exception.NovaException(_('%s is not set') % flag)
+                raise exception.InvalidInput(reason=_('%s is not set') % flag)
         if not (FLAGS.netapp_storage_service or
                 FLAGS.netapp_storage_service_prefix):
-            raise exception.NovaException(_('Either netapp_storage_service or '
-                'netapp_storage_service_prefix must be set'))
+            raise exception.InvalidInput(reason=_('Either '
+                'netapp_storage_service or netapp_storage_service_prefix must '
+                'be set'))
 
     def do_setup(self, context):
         """Setup the NetApp Volume driver.
@@ -293,8 +294,8 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
             events = self._get_job_progress(job_id)
             for event in events:
                 if event.EventStatus == 'error':
-                    raise exception.NovaException(_('Job failed: %s') %
-                        (event.ErrorMessage))
+                    msg = _('Job failed: %s') % (event.ErrorMessage)
+                    raise exception.VolumeBackendAPIException(data=msg)
                 if event.EventType == 'job-end':
                     return events
             time.sleep(5)
@@ -324,11 +325,11 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         if ss_type and not self.storage_service_prefix:
             msg = _('Attempt to use volume_type without specifying '
                 'netapp_storage_service_prefix flag.')
-            raise exception.NovaException(msg)
+            raise exception.VolumeBackendAPIException(data=msg)
         if not (ss_type or self.storage_service):
             msg = _('You must set the netapp_storage_service flag in order to '
                 'create volumes with no volume_type.')
-            raise exception.NovaException(msg)
+            raise exception.VolumeBackendAPIException(data=msg)
         storage_service = self.storage_service
         if ss_type:
             storage_service = self.storage_service_prefix + ss_type
@@ -396,7 +397,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         except (suds.WebFault, Exception):
             server.DatasetEditRollback(EditLockId=lock_id)
             msg = _('Failed to provision dataset member')
-            raise exception.NovaException(msg)
+            raise exception.VolumeBackendAPIException(data=msg)
 
         lun_id = None
         lunpath = None
@@ -411,7 +412,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
 
         if not lun_id:
             msg = _('No LUN was created by the provision job')
-            raise exception.NovaException(msg)
+            raise exception.VolumeBackendAPIException(data=msg)
 
         lun = DfmLun(dataset, lunpath, lun_id)
         self.discovered_luns.append(lun)
@@ -449,7 +450,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         except (suds.WebFault, Exception):
             server.DatasetEditRollback(EditLockId=lock_id)
             msg = _('Failed to remove and delete dataset member')
-            raise exception.NovaException(msg)
+            raise exception.VolumeBackendAPIException(data=msg)
 
     def create_volume(self, volume):
         """Driver entry point for creating a new volume."""
@@ -489,8 +490,8 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
             if lun.lunpath.endswith(lunpath_suffix):
                 self.lun_table[name] = lun
                 return lun
-        msg = _("No entry in LUN table for volume %s")
-        raise exception.NovaException(msg % (name))
+        msg = _("No entry in LUN table for volume %s") % (name)
+        raise exception.VolumeBackendAPIException(data=msg)
 
     def delete_volume(self, volume):
         """Driver entry point for destroying existing volumes."""
@@ -510,7 +511,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         finally:
             server.LunListInfoIterEnd(Tag=tag)
         msg = _('Failed to get LUN details for LUN ID %s')
-        raise exception.NovaException(msg % lun_id)
+        raise exception.VolumeBackendAPIException(data=msg % lun_id)
 
     def _get_host_details(self, host_id):
         """Given the ID of a host, get the details about it.
@@ -527,7 +528,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         finally:
             server.HostListInfoIterEnd(Tag=tag)
         msg = _('Failed to get host details for host ID %s')
-        raise exception.NovaException(msg % host_id)
+        raise exception.VolumeBackendAPIException(data=msg % host_id)
 
     def _get_iqn_for_host(self, host_id):
         """Get the iSCSI Target Name for a storage system."""
@@ -763,8 +764,8 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         initiator_name = connector['initiator']
         lun_id = volume['provider_location']
         if not lun_id:
-            msg = _("No LUN ID for volume %s")
-            raise exception.NovaException(msg % volume['name'])
+            msg = _("No LUN ID for volume %s") % volume['name']
+            raise exception.VolumeBackendAPIException(data=msg)
         lun = self._get_lun_details(lun_id)
         lun_num = self._ensure_initiator_mapped(lun.HostId, lun.LunPath,
                                                 initiator_name)
@@ -773,12 +774,12 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
                                                   host.HostAddress)
         if not portal:
             msg = _('Failed to get target portal for filer: %s')
-            raise exception.NovaException(msg % host.HostName)
+            raise exception.VolumeBackendAPIException(data=msg % host.HostName)
 
         iqn = self._get_iqn_for_host(host.HostId)
         if not iqn:
             msg = _('Failed to get target IQN for filer: %s')
-            raise exception.NovaException(msg % host.HostName)
+            raise exception.VolumeBackendAPIException(data=msg % host.HostName)
 
         properties = {}
         properties['target_discovered'] = False
@@ -810,8 +811,8 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         initiator_name = connector['initiator']
         lun_id = volume['provider_location']
         if not lun_id:
-            msg = _('No LUN ID for volume %s')
-            raise exception.NovaException(msg % (volume['name']))
+            msg = _('No LUN ID for volume %s') % volume['name']
+            raise exception.VolumeBackendAPIException(data=msg)
         lun = self._get_lun_details(lun_id)
         self._ensure_initiator_unmapped(lun.HostId, lun.LunPath,
                                         initiator_name)
@@ -966,7 +967,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         if vol_size != snap_size:
             msg = _('Cannot create volume of size %(vol_size)s from '
                 'snapshot of size %(snap_size)s')
-            raise exception.NovaException(msg % locals())
+            raise exception.VolumeBackendAPIException(data=msg % locals())
         vol_name = snapshot['volume_name']
         snapshot_name = snapshot['name']
         project = snapshot['project_id']
@@ -978,7 +979,7 @@ class NetAppISCSIDriver(driver.ISCSIDriver):
         if new_type != old_type:
             msg = _('Cannot create volume of type %(new_type)s from '
                 'snapshot of type %(old_type)s')
-            raise exception.NovaException(msg % locals())
+            raise exception.VolumeBackendAPIException(data=msg % locals())
         lun = self._get_lun_details(lun_id)
         extra_gb = vol_size
         new_size = '+%dg' % extra_gb
diff --git a/nova/volume/san.py b/nova/volume/san.py
index 6fe46b1db..e6927a12d 100644
--- a/nova/volume/san.py
+++ b/nova/volume/san.py
@@ -112,7 +112,7 @@ class SanISCSIDriver(nova.volume.driver.ISCSIDriver):
                         pkey=privatekey)
         else:
             msg = _("Specify san_password or san_private_key")
-            raise exception.NovaException(msg)
+            raise exception.InvalidInput(reason=msg)
         return ssh
 
     def _execute(self, *cmd, **kwargs):
@@ -150,12 +150,12 @@ class SanISCSIDriver(nova.volume.driver.ISCSIDriver):
         """Returns an error if prerequisites aren't met."""
         if not self.run_local:
             if not (FLAGS.san_password or FLAGS.san_private_key):
-                raise exception.NovaException(_('Specify san_password or '
-                                        'san_private_key'))
+                raise exception.InvalidInput(
+                    reason=_('Specify san_password or san_private_key'))
 
         # The san_ip must always be set, because we use it for the target
         if not (FLAGS.san_ip):
-            raise exception.NovaException(_("san_ip must be set"))
+            raise exception.InvalidInput(reason=_("san_ip must be set"))
 
 
 def _collect_lines(data):
@@ -226,8 +226,8 @@ class SolarisISCSIDriver(SanISCSIDriver):
         if "View Entry:" in out:
             return True
 
-        msg = _("Cannot parse list-view output: %s") % (out)
-        raise exception.NovaException()
+        msg = _("Cannot parse list-view output: %s") % out
+        raise exception.VolumeBackendAPIException(data=msg)
 
     def _get_target_groups(self):
         """Gets list of target groups from host."""
@@ -320,8 +320,9 @@ class SolarisISCSIDriver(SanISCSIDriver):
                 luid = items[0].strip()
                 return luid
 
-        raise Exception(_('LUID not found for %(zfs_poolname)s. '
-                          'Output=%(out)s') % locals())
+        msg = _('LUID not found for %(zfs_poolname)s. '
+                'Output=%(out)s') % locals()
+        raise exception.VolumeBackendAPIException(data=msg)
 
     def _is_lu_created(self, volume):
         luid = self._get_luid(volume)
@@ -461,7 +462,7 @@ class HpSanISCSIDriver(SanISCSIDriver):
                 msg = (_("Malformed response to CLIQ command "
                          "%(verb)s %(cliq_args)s. Result=%(out)s") %
                        locals())
-                raise exception.NovaException(msg)
+                raise exception.VolumeBackendAPIException(data=msg)
 
             result_code = response_node.attrib.get("result")
 
@@ -469,7 +470,7 @@ class HpSanISCSIDriver(SanISCSIDriver):
                 msg = (_("Error running CLIQ command %(verb)s %(cliq_args)s. "
                          " Result=%(out)s") %
                        locals())
-                raise exception.NovaException(msg)
+                raise exception.VolumeBackendAPIException(data=msg)
 
         return result_xml
 
@@ -499,7 +500,7 @@ class HpSanISCSIDriver(SanISCSIDriver):
         msg = (_("Unexpected number of virtual ips for cluster "
                  " %(cluster_name)s. Result=%(_xml)s") %
                locals())
-        raise exception.NovaException(msg)
+        raise exception.VolumeBackendAPIException(data=msg)
 
     def _cliq_get_volume_info(self, volume_name):
         """Gets the volume info, including IQN"""
@@ -602,7 +603,8 @@ class HpSanISCSIDriver(SanISCSIDriver):
 
     def local_path(self, volume):
         # TODO(justinsb): Is this needed here?
-        raise exception.NovaException(_("local_path not supported"))
+        msg = _("local_path not supported")
+        raise exception.VolumeBackendAPIException(data=msg)
 
     def initialize_connection(self, volume, connector):
         """Assigns the volume to a server.
diff --git a/nova/volume/storwize_svc.py b/nova/volume/storwize_svc.py
index dc3ed309d..d9b92126e 100644
--- a/nova/volume/storwize_svc.py
+++ b/nova/volume/storwize_svc.py
@@ -151,9 +151,9 @@ class StorwizeSVCDriver(san.SanISCSIDriver):
                    'err': str(err)})
         search_text = '!%s!' % getattr(FLAGS, 'storwize_svc_volpool_name')
         if search_text not in out:
-            raise exception.InvalidParameterValue(
-                    err=_('pool %s doesn\'t exist')
-                        % getattr(FLAGS, 'storwize_svc_volpool_name'))
+            raise exception.InvalidInput(
+                    reason=(_('pool %s doesn\'t exist')
+                        % getattr(FLAGS, 'storwize_svc_volpool_name')))
 
         storage_nodes = {}
         # Get the iSCSI names of the Storwize/SVC nodes
@@ -322,63 +322,64 @@ class StorwizeSVCDriver(san.SanISCSIDriver):
                           'storwize_svc_volpool_name']
         for flag in required_flags:
             if not getattr(FLAGS, flag, None):
-                raise exception.InvalidParameterValue(
-                        err=_('%s is not set') % flag)
+                raise exception.InvalidInput(
+                        reason=_('%s is not set') % flag)
 
         # Ensure that either password or keyfile were set
         if not (getattr(FLAGS, 'san_password', None)
                 or getattr(FLAGS, 'san_private_key', None)):
-            raise exception.InvalidParameterValue(
-                err=_('Password or SSH private key is required for '
-                      'authentication: set either san_password or '
-                      'san_private_key option'))
+            raise exception.InvalidInput(
+                reason=_('Password or SSH private key is required for '
+                         'authentication: set either san_password or '
+                         'san_private_key option'))
 
         # vtype should either be 'striped' or 'seq'
         vtype = getattr(FLAGS, 'storwize_svc_vol_vtype')
         if vtype not in ['striped', 'seq']:
-            raise exception.InvalidParameterValue(
-                err=_('Illegal value specified for storwize_svc_vol_vtype: '
-                  'set to either \'striped\' or \'seq\''))
+            raise exception.InvalidInput(
+                reason=_('Illegal value specified for storwize_svc_vol_vtype: '
+                         'set to either \'striped\' or \'seq\''))
 
         # Check that rsize is a number or percentage
         rsize = getattr(FLAGS, 'storwize_svc_vol_rsize')
         if not self._check_num_perc(rsize) and (rsize not in ['auto', '-1']):
-            raise exception.InvalidParameterValue(
-                err=_('Illegal value specified for storwize_svc_vol_rsize: '
-                  'set to either a number or a percentage'))
+            raise exception.InvalidInput(
+                reason=_('Illegal value specified for storwize_svc_vol_rsize: '
+                         'set to either a number or a percentage'))
 
         # Check that warning is a number or percentage
         warning = getattr(FLAGS, 'storwize_svc_vol_warning')
         if not self._check_num_perc(warning):
-            raise exception.InvalidParameterValue(
-                err=_('Illegal value specified for storwize_svc_vol_warning: '
-                  'set to either a number or a percentage'))
+            raise exception.InvalidInput(
+                reason=_('Illegal value specified for '
+                         'storwize_svc_vol_warning: '
+                         'set to either a number or a percentage'))
 
         # Check that autoexpand is a boolean
         autoexpand = getattr(FLAGS, 'storwize_svc_vol_autoexpand')
         if type(autoexpand) != type(True):
-            raise exception.InvalidParameterValue(
-                err=_('Illegal value specified for '
-                  'storwize_svc_vol_autoexpand: set to either '
-                  'True or False'))
+            raise exception.InvalidInput(
+                reason=_('Illegal value specified for '
+                         'storwize_svc_vol_autoexpand: set to either '
+                         'True or False'))
 
         # Check that grainsize is 32/64/128/256
         grainsize = getattr(FLAGS, 'storwize_svc_vol_grainsize')
         if grainsize not in ['32', '64', '128', '256']:
-            raise exception.InvalidParameterValue(
-                err=_('Illegal value specified for '
-                  'storwize_svc_vol_grainsize: set to either '
-                  '\'32\', \'64\', \'128\', or \'256\''))
+            raise exception.InvalidInput(
+                reason=_('Illegal value specified for '
+                         'storwize_svc_vol_grainsize: set to either '
+                         '\'32\', \'64\', \'128\', or \'256\''))
 
         # Check that flashcopy_timeout is numeric and 32/64/128/256
         flashcopy_timeout = getattr(FLAGS, 'storwize_svc_flashcopy_timeout')
         if not (flashcopy_timeout.isdigit() and int(flashcopy_timeout) > 0 and
             int(flashcopy_timeout) <= 600):
-            raise exception.InvalidParameterValue(
-                err=_('Illegal value %s specified for '
-                      'storwize_svc_flashcopy_timeout: '
-                      'valid values are between 0 and 600')
-                      % flashcopy_timeout)
+            raise exception.InvalidInput(
+                reason=_('Illegal value %s specified for '
+                         'storwize_svc_flashcopy_timeout: '
+                         'valid values are between 0 and 600')
+                                         % flashcopy_timeout)
 
         # Check that compression is a boolean
         volume_compression = getattr(FLAGS, 'storwize_svc_vol_compression')
diff --git a/nova/volume/xensm.py b/nova/volume/xensm.py
index bde69e60d..3deec66f0 100644
--- a/nova/volume/xensm.py
+++ b/nova/volume/xensm.py
@@ -59,7 +59,8 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
             except Exception as ex:
                 LOG.debug(_("Failed to create sr %s...continuing") %
                           str(backend_ref['id']))
-                raise exception.NovaException(_('Create failed'))
+                msg = _('Create failed')
+                raise exception.VolumeBackendAPIException(data=msg)
 
             LOG.debug(_('SR UUID of new SR is: %s') % sr_uuid)
             try:
@@ -68,7 +69,8 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
                                                dict(sr_uuid=sr_uuid))
             except Exception as ex:
                 LOG.exception(ex)
-                raise exception.NovaException(_("Failed to update db"))
+                msg = _("Failed to update db")
+                raise exception.VolumeBackendAPIException(data=msg)
 
         else:
             # sr introduce, if not already done
@@ -88,8 +90,8 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
                 self._create_storage_repo(context, backend)
             except Exception as ex:
                 LOG.exception(ex)
-                raise exception.NovaException(_('Failed to reach backend %d')
-                                      % backend['id'])
+                msg = _('Failed to reach backend %d') % backend['id']
+                raise exception.VolumeBackendAPIException(data=msg)
 
     def __init__(self, *args, **kwargs):
         """Connect to the hypervisor."""
@@ -98,7 +100,7 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
         # hypervisor to be Xen
         if FLAGS.connection_type != 'xenapi':
             msg = _('XenSMDriver requires xenapi connection')
-            raise exception.NovaException(msg)
+            raise exception.VolumeBackendAPIException(data=msg)
 
         url = FLAGS.xenapi_connection_url
         username = FLAGS.xenapi_connection_username
@@ -108,7 +110,8 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
             self._volumeops = volumeops.VolumeOps(session)
         except Exception as ex:
             LOG.exception(ex)
-            raise exception.NovaException(_("Failed to initiate session"))
+            msg = _("Failed to initiate session")
+            raise exception.VolumeBackendAPIException(data=msg)
 
         super(XenSMDriver, self).__init__(execute=utils.execute,
                                           sync_exec=utils.execute,
@@ -153,10 +156,11 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
             except Exception as ex:
                 LOG.exception(ex)
                 msg = _("Failed to update volume in db")
-                raise exception.NovaException(msg)
+                raise exception.VolumeBackendAPIException(data=msg)
 
         else:
-            raise exception.NovaException(_('Unable to create volume'))
+            msg = _('Unable to create volume')
+            raise exception.VolumeBackendAPIException(data=msg)
 
     def delete_volume(self, volume):
 
@@ -172,13 +176,15 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
             self._volumeops.delete_volume_for_sm(vol_rec['vdi_uuid'])
         except Exception as ex:
             LOG.exception(ex)
-            raise exception.NovaException(_("Failed to delete vdi"))
+            msg = _("Failed to delete vdi")
+            raise exception.VolumeBackendAPIException(data=msg)
 
         try:
             self.db.sm_volume_delete(self.ctxt, volume['id'])
         except Exception as ex:
             LOG.exception(ex)
-            raise exception.NovaException(_("Failed to delete volume in db"))
+            msg = _("Failed to delete volume in db")
+            raise exception.VolumeBackendAPIException(data=msg)
 
     def local_path(self, volume):
         return str(volume['id'])
@@ -211,7 +217,8 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
                                                           volume['id']))
         except Exception as ex:
             LOG.exception(ex)
-            raise exception.NovaException(_("Failed to find volume in db"))
+            msg = _("Failed to find volume in db")
+            raise exception.VolumeBackendAPIException(data=msg)
 
         # Keep the volume id key consistent with what ISCSI driver calls it
         xensm_properties['volume_id'] = xensm_properties['id']
@@ -222,7 +229,8 @@ class XenSMDriver(nova.volume.driver.VolumeDriver):
                                   xensm_properties['backend_id'])
         except Exception as ex:
             LOG.exception(ex)
-            raise exception.NovaException(_("Failed to find backend in db"))
+            msg = _("Failed to find backend in db")
+            raise exception.VolumeBackendAPIException(data=msg)
 
         params = self._convert_config_params(backend_conf['config_params'])