Sure. It's basically code from dm-linear.c and dm-stripe.c (you can
reverse chunks of a given size). The target syntax is "<chunk size>
<device> <first sector>".

I added some lines so that it can be compiled as module outside of the
kernel (the reference counting is working fine).

dm-reverse.c is attached.

--
Christophe Saout <christophe@saout.de>
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