[dm-devel] Re: A simple, generic DM-API, for codecs/transcoders to use?

[Wes Felter]

Navid Zamani wrote:
> Hello DM mailing list.
> 
> I a have a simple question:
> Is there a way to use the device-mapper to hang an arbitrary program
> in-between a real block device, and the virtual device created by the
> device-mapper?

http://static.danplanet.com/dm-userspace/

> In case you are interested in the reasons: Modern consumer HDDs do not
> have any ECC, but they get less and less reliable.

I don't think this is correct. All disks use ECC; cheap disks just don't 
use strong enough ECC. 4K sectors may fix this in the distant future.

> So I decided to put my whole archive on a partititon with software-based
> ECC. And because I could not find something that resembled this, I chose
> to implement it myself.

Honestly I would use RAID + Btrfs instead of software ECC. But if you're 
determined to go down this path, you may want to investigate LDPC 
instead of RS.

Wes Felter - wesley at felter.org