How to get volume mount point while cloning linux server using vCenter Converter SDK

I Use the following code to get volume mount point while cloning linux server.

But sometimes VolumeInfo[count].getLabel() get empty information.

Is there any constraint in this API? Is there any other API can get volume mount point ?

ConverterComputerInfo _converterSrcInfo = _converterServer.GetConverterQuery(buildLiveSourceSpec());

ConverterStorageInfoVolumeInfo VolumeInfo[] = _converterSrcInfo.getHardwareInfo().getStorage().getVolume();

VolumeInfo[count].getLabel();

Thanks

Scott