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From: Arnd Bergmann <arnd@arndb.de>
To: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Subject: Re: [PATCH 41/44 take 2] [UBI] gluebi unit header
Date: Sun, 18 Feb 2007 23:37:51 +0100
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On Sunday 18 February 2007 04:02:17 Josh Boyer wrote:
> On Sun, Feb 18, 2007 at 03:15:23AM +0100, Arnd Bergmann wrote:
> > On Sunday 18 February 2007 03:04, Josh Boyer wrote:
> > > No, the MTD interface isn't flawed.  gluebi is present to make things
> > > like JFFS2 work on top of UBI volumes with very little adaptations.  If
> > > you go changing _every_ MTD user to now use either an MTD device or a
> > > native UBI device, then the code for those users just gets bloated.
> >
> > Right, that was my point. If the MTD API in the kernel is not flawed, why
> > do we need the 'native' UBI interface? Just merge gluebi into UBI and
> > get rid of the extra abstraction.
>
> That suggestion came up several times.  gluebi represents a compromise
> between the two groups.  IIRC, the issue was that representing UBI volumes
> as MTD devices only makes sense in the dynamic volume case.  Static UBI
> volumes require special write/update handling and so there was a need for
> a native interface anyway.

Which brings be back to my original point ;-)

I'm sure this has been discussed before, but I'd still like to understand
what is so special with 'static UBI volumes' that they can't be used with
a slightly extended MTD interface.

	Arnd <><