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Subject: Re: [PATCHv3] UBI: new module ubiblk: block layer on top of UBI
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Arnd Bergmann <arnd@arndb.de>
Date: Tue, 06 Sep 2011 07:29:51 +0300
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On Tue, 2011-09-06 at 07:10 +0300, Artem Bityutskiy wrote:
> On Tue, 2011-09-06 at 06:44 +0300, Artem Bityutskiy wrote:
> > > It's not a dummy bus, in this approach it would be a the bus that gets
> > > used by all ubiblk devices, which is a very common concept by itself.
> > > It's more like the classic understanding of a 'device class' that Greg
> > > wants to see get replaced by bus_types in the kernel.
> > 
> > Yes, this sounds OK. Although UBI already has notifiers, so we could
> > just add 2 more events.
> 
> Hmm, with notifications the error handling becomes a problem - we want
> the ioctls for creating/removing the block device to be synchronous,
> and, should an error occur, we want to return the error code to the
> user-space. So the existing notifications mechanism does not work well.

... but we can change it a little and have error codes handling, this is
just UB implementation issues.

-- 
Best Regards,
Artem Bityutskiy