diskid documentation

[Pawel Jakub Dawidek]

On Mon, Jun 02, 2014 at 03:27:06PM -0700, John-Mark Gurney wrote:
> Pawel Jakub Dawidek wrote this message on Mon, Jun 02, 2014 at 22:26 +0200:
> > The problem is that GPT labels (or GPT IDs for that matter) should not
> > be implemented within GLABEL. This is wrong. It should be implemented as
> > part of GPART, so that GPART would create ada0p1, gpt/label and
> > gptid/whatever. Opening one of those should not make the others
> > disappear then. Only opening ada0 for writting would make them disappear.
> 
> even gpart would be wrong IMO... What happens if there is another
> provider like GPART, but different, do they need to implement diskid
> creation too to prevent the same issue?
> 
> Shouldn't geom be updated to say, this ident is an alias, everything
> you do w/ this, it's exactly the same as the other one?  This would
> also have the advantage of possibly removing one layer in the call
> chain when dealing w/ IO. (or does GEOM has a pass-through flag that
> says, I don't do anything, just skip me?)

As for disk IDs it definitely shouldn't be implemented in GPART or
GLABEL. IMHO the right place is the DISK class - both ada0 and
diskid-of-ada0 should exist on the same rights (two providers of one
geom). This also would address your concern about additional layer.

-- 
Pawel Jakub Dawidek                       http://www.wheelsystems.com
FreeBSD committer                         http://www.FreeBSD.org
Am I Evil? Yes, I Am!                     http://mobter.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 196 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-geom/attachments/20140604/70edee56/attachment.sig>