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Date: Fri, 7 Aug 2009 23:28:46 +0800
From: JiSheng Zhang <jszhang3@gmail.com>
To: Adrian Hunter <adrian.hunter@nokia.com>
Subject: Re: [UBI UBIFS] replace vmalloc with kmalloc
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Adrian Hunter <adrian.hunter@nokia.com> wrote:
> 
> vmalloc allows large (> 128KiB) buffers, but kmalloc doesn't.
> So we presently have no choice but to use vmalloc.

But vmalloced buffer can't be easily passed to DMA, is there better choice?

> 
> I do not know what hardware you have or exactly what driver you
> are using, but we have UBIFS on OneNAND using DMA.

An arm soc board, the controller driver hasn't been merged upstream.
> See drivers/mtd/onenand/omap2.c
>

One limit of the omap2.c is that the buffer passed to DMA can't be larger than
PAGESIZE?

Jisheng