Re: [PATCH] mmc_spi: use EILSEQ for possible transmission errors

From: Pierre Ossman
Date: Mon May 25 2009 - 07:48:47 EST

On Wed, 20 May 2009 19:02:51 -0700
David Brownell <david-b@xxxxxxxxxxx> wrote:

> On Wednesday 20 May 2009, Pierre Ossman wrote:
> > > Remember that the
> > > firmware in the card can leverage "that's erased" knowledge for
> > > things like wear leveling. ÂSSDs and other storage devices would
> > > likewise benefit from such knowledge. ÂI'm quite certain there's
> > > been discussion about adding support for that in the block layer.
> >
> > It's already in AFAIK. I even had code for hooking it up to mmc_block.
> > But it didn't produce any measurable results so I never merged it.
> I'd expect the results would take time to show. As in, they would
> facilitate wear leveling logic, which may be difficult to measure
> except by testing various cards to destruction ... even for vendors
> that *do* have decent wear leveling. :)

Who are these mythical decent vendors you speak of? ;)

Seriously though, the modifications to mmc_block can still be found
here if anyone wants to play with it:

I haven't checked if it still applies to the current version of the
kernel though, so you're on your own. ;)

-- Pierre Ossman

WARNING: This correspondence is being monitored by the
Swedish government. Make sure your server uses encryption
for SMTP traffic and consider using PGP for end-to-end

Attachment: signature.asc
Description: PGP signature