mapped devices and filesystem

(mapped-devices
   (list (mapped-device
          (source (uuid "6da2634c-710a-4061-b878-38e0c0c1f615"))
          (target "my-home")
          (type luks-device-mapping))))
  ;; Specify a mapped device for the encrypted root partition.
  ;; The UUID is that returned by 'cryptsetup luksUUID'.
  (file-systems (cons* (file-system
                        (device "root")
			(title 'label)
                        (mount-point "/")
                        (type "ext4"))
		      (file-system
                        (device (uuid "3FDD-83DF" 'fat))
			(title 'uuid)
                        (mount-point "/boot/efi")
                        (type "vfat"))
		      (file-system
                        (device "/dev/mapper/my-home")
			(title 'device)
                        (mount-point "/home")
                        (type "ext4"))
			;;(needed-for-boot? #f)
			;;(mount? #f)
                        ;;(dependencies mapped-devices))
                      %base-file-systems))