#!/bin/bash

if [[ -z $1 ]] ; then
	echo "Usage: $0 <root>"
	exit 1
fi

prompt=true
case $1 in
-y) prompt=false; shift;;
esac

while [[ $# -gt 0 ]] ; do

root=$1
shift

mounts=$(gawk -v p="${root%/}" '$2 ~ "^"p { print $2 }' /proc/mounts | tac)
if [[ -z ${mounts} ]] ; then
	echo "No mounts found ..."
	echo
	mount
	continue
fi

echo "Unmounting: "
printf '\t%s\n' ${mounts}

if ${prompt} ; then
	printf "OK? [y/N] "
	read v
else
	v=y
fi
[[ ${v} == "y" ]] && sudo umount -v ${mounts}

done