code: public Task unmountDiskMapping_Task(VsanHostDiskMapping[] mapping) throws InvalidState, RuntimeFault, VsanFault, RemoteException {
          return new Task(getServerConnection(), getVimService().unmountDiskMapping_Task(getMOR(), mapping));
      }
docs: Unmount the mounted DiskMapping. An unmounted volume cannot be used for any VSAN operations. In contrast to
  RemoveDiskMapping_Task, this operation does not destroy or alter VSAN data on the disks. AddDisks_Task and
  InitializeDisks_Task can be used to re-mount the diskMapping.
  
  @param mapping Mapping
  @return This method returns a Task object with which to monitor the operation.
  @throws InvalidState
  @throws RuntimeFault
  @throws VsanFault
  @throws RemoteException