Docker - setting the default size of images with device mapper storage driver

Been playing around with docker (http://docker.io) for a while now to see if it can help create a one script setup for setting up the build environment for the avr8 toolchain. One pesky problem when using the device mapper storage driver (the default on RHEL) is that the created images/containers are small - only 10G. That isn’t going to cut it for building the GNU toolchain - the gcc repo itself takes up 2.