None
umount.crypt - unmount a dm-crypt encrypted volume
umount.crypt [-n] directory
-f
This option is ignored (originally is "force unmount for NFS").
-n
Do not update /etc/mtab.
-r
Try mounting read-only if unmounting fails. This option is currently not implemented and is ignored.
umount.crypt will unmount directory and disassociates the underlying crypto device, and loop device if such was used.