Re: dm core patches

[Jens Axboe <axboe@suse.de>]

On Fri, Feb 13 2004, Lars Marowsky-Bree wrote:
> > The other thing we need is to try and get the drivers to deferentiate
> > between a media error and a path error, so that media errors get
> > reported up quickly and don't cause false path failures.  This is
> > possibly an area that you could help with ?
> 
> I thought the IO stack in 2.6 provided us with such sense keys already,
> which you'd then need to handle in the DM personality. Of course,
> drivers need to make sure they pass up appropriate sense-keys, but
> that's a hardware vendor issue and not something which should delay the
> DM personality...
> 
> Jens, do you have the pointer on this handy?

The mechanism is in place, but the SCSI stack still needs a few changes
to pass down the correct errors. The easiest would be to pass down
pseudo-sense keys (I'd rather just call them something else as not to
confuse things, io error hints or something) to
end_that_request_first(), changing uptodate from a bool to a hint.

I can help get this done, it's not something that should hold up dm-mp
by any stretch.

-- 
Jens Axboe