Hi!

I just wrote a dm target uses a file as backend instead of another block
device.

It's heavily based on the linux 2.5 loop device (so it uses the inode
operation sendfile for read operations and the address space operations
prepare_write and commit_write for write operations).

A dm device can be created with the target options "filename offset"
where offset is given in bytes.

--
Christophe Saout <christophe@saout.de>
Please avoid sending me Word or PowerPoint attachments.
See http://www.fsf.org/philosophy/no-word-attachments.html