code: func SelectDisks(l object.VirtualDeviceList, count int) object.VirtualDeviceList {
  	devices := l.Select(func(device types.BaseVirtualDevice) bool {
  		if disk, ok := device.(*types.VirtualDisk); ok {
  			ctlr, err := findControllerForDevice(l, disk)
  			if err != nil {
  				log.Printf("[DEBUG] DiskRefreshOperation: Error looking for controller for device %q: %s", l.Name(disk), err)
  				return false
  			}
  			if sc, ok := ctlr.(types.BaseVirtualSCSIController); ok && sc.GetVirtualSCSIController().BusNumber < int32(count) {
  				cd := sc.(types.BaseVirtualDevice)
  				log.Printf("[DEBUG] DiskRefreshOperation: Found controller %q for device %q", l.Name(cd), l.Name(disk))
  				return true
  			}
  		}
  		return false
  	})
  	return devices
  }
docs: // SelectDisks looks for disks that Terraform is supposed to manage. count is
  // the number of controllers that Terraform is managing and serves as an upper
  // limit (count - 1) of the SCSI bus number for a controller that eligible
  // disks need to be attached to.