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Subject: Re: atmel_nand, DMA, and "Fall back to CPU I/O"
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Brian Norris <computersforpeace@gmail.com>
Date: Thu, 03 May 2012 13:35:18 +0300
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Cc: George Pontis <GPontis@z9.com>, linux-mtd@lists.infradead.org
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On Wed, 2012-05-02 at 12:32 -0700, Brian Norris wrote:
>=20
> And how might you recommend we use kmalloc()'ed memory, Artem? We
> can't really kmalloc() whole eraseblock-sized chunks. Or is there an
> inexpensive way of providing an intermediary kmalloc'ed buffer? I'm
> not too familiar at hacking at UBI(FS), but it might be worth a shot
> sometime, if you think it's reasonable.

This would need to change several places in UBI and UBIFS and switch
from continuous vmalloc buffers to iterating over an array of smaller
buffers.

I was thinking about this in the past but this is rather big project (a
months or a couple I'd say) so I did not have time to do this.

I think we basically need to switch to flexible arrays
(Documentation/flexible-arrays.txt), but last time I looked at this I
remember I decided that flexible arrays functionality would need to be
extended for our purposes.

If someone seriously is going to do this work, I am happy to discuss.

--=20
Best Regards,
Artem Bityutskiy

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