It does exactly what you want, although it was created for different use cases (Live CDs, layered images as used by Docker, etc.):
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux....
It does exactly what you want, although it was created for different use cases (Live CDs, layered images as used by Docker, etc.):
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux....