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Date: Mon, 24 Aug 2009 21:48:00 +0200
From: Christoph Hellwig <hch@lst.de>
To: Becky Bruce <beckyb@kernel.crashing.org>
Subject: Re: [PATCH] powerpc: Change archdata dma_data type to dma_addr_t
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On Mon, Aug 24, 2009 at 11:17:14AM -0500, Becky Bruce wrote:
> Previously, this was specified as a void *, but that's not
> large enough on 32-bit systems with 36-bit physical
> addressing support.  Change the type to dma_addr_t so it
> will scale based on the size of a dma address.

This looks extreml ugly to me.  It seems like the typical use is to
store a pointer to a structure.  So what about making the direct
dma case follow that general scheme instead?

E.g. declare a

struct direct_dma_data {
	dma_addr_t	direct_dma_offset;
};

and have one normal instace of it, and one per weird cell device.