[dm-devel] New dm development

[Kevin Corry]

On Wednesday 07 July 2004 4:15 pm, Allen Jack wrote:
> I am interested in developing 2 new target types for the device-mapper.
> Could you point me in the right direction on how to plug my drivers into
> the device-mapper frame?  One of these is a RAID1 type target, and
> another is a RAID5 type target.  Any help here would be great.  I have
> never written dm drivers before.

Well, the best place to start is to review some of the existing targets (in 
drivers/md/ in the kernel source tree) to see how they work in the DM 
framework. dm-linear and dm-stripe are both simple targets and will give you 
a good starting point. And there are several more complicated ones to review 
once you understand the basics.

Also, DM already has a raid1 target. Have you taken a look at that one yet? If 
that one doesn't quite meet your needs, it would definitely be preferrable to 
try to add on to it if at all possible rather than start a whole new one.

A raid5 target would certainly be very nice to have. Will you be trying to 
reuse code from MD's raid5 personality?

-- 
Kevin Corry
kevcorry at us.ibm.com
http://evms.sourceforge.net/