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Date: Thu, 7 Dec 2006 10:11:51 +0000
From: Christoph Hellwig <hch@infradead.org>
To: Linas Vepstas <linas@austin.ibm.com>
Subject: Re: [PATCH 1/16] Spidernet DMA coalescing
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	<20061206232745.GA4649@austin.ibm.com>
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Cc: Andrew Morton <akpm@osdl.org>, Arnd Bergmann <arnd@arndb.de>,
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On Wed, Dec 06, 2006 at 05:27:45PM -0600, Linas Vepstas wrote:
> 
> The current driver code performs 512 DMA mappings of a bunch of 
> 32-byte structures. This is silly, as they are all in contiguous 
> memory. Ths patch changes the code to DMA map the entie area
> with just one call.

This is still wrong.  The descriptor array must be in dma_alloc_coherent
memory, not a streaming mapping.  (I also think I pointed this out a while
ago when I made dma_alloc_coherent node-aware)