code: func diskCapacityInGiB(disk *types.VirtualDisk) int {
  	if disk.CapacityInBytes > 0 {
  		return int(structure.ByteToGiB(disk.CapacityInBytes).(int64))
  	}
  	log.Printf(
  		"[DEBUG] diskCapacityInGiB: capacityInBytes missing for for %s, falling back to capacityInKB",
  		object.VirtualDeviceList{}.Name(disk),
  	)
  	return int(structure.ByteToGiB(disk.CapacityInKB * 1024).(int64))
  }
docs: // diskCapacityInGiB reports the supplied disk's capacity, by first checking
  // CapacityInBytes, and then falling back to CapacityInKB if that value is
  // unavailable. This helps correct some situations where the former value's
  // data gets cleared, which seems to happen on upgrades.