#!/bin/bash
# $1 VG
# $2 LV
# $2 SIZE eg '800.00 MB'

lvdisplay | grep -A 5 'LV Name.*/dev/mapper/'$1-$2 | grep -q available || exit 1
lvdisplay | grep -A 7 'LV Name.*/dev/mapper/'$1-$2 | grep -q 'LV Size.*'"$2" || exit 2