'Get the disk device of the VM which corresponds to the given path.
:param vm: VM reference
:param vmdk_path: Datastore path of virtual disk
:return: Matching disk device'

def get_disk_device(self, vm, vmdk_path):

    disk_devices = self._get_disk_devices(vm)
    for disk_device in disk_devices:
        backing = disk_device.backing
        if ((backing.__class__.__name__ == 'VirtualDiskFlatVer2BackingInfo') and (backing.fileName == vmdk_path)):
            return disk_device
