Date: Tue, 02 Jan 2007 16:20:58 -0800 (PST)
Message-Id: <20070102.162058.55482337.davem@davemloft.net>
To: James.Bottomley@SteelEye.com
Cc: rmk+lkml@arm.linux.org.uk, miklos@szeredi.hu, arjan@infradead.org,
       torvalds@osdl.org, linux-kernel@vger.kernel.org,
       linux-arch@vger.kernel.org, akpm@osdl.org
Subject: Re: fuse, get_user_pages, flush_anon_page, aliasing caches and all
 that again
From: David Miller <davem@davemloft.net>
In-Reply-To: <1167780858.3687.13.camel@mulgrave.il.steeleye.com>
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	<20070102.151906.21595863.davem@davemloft.net>
	<1167780858.3687.13.camel@mulgrave.il.steeleye.com>
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From: James Bottomley <James.Bottomley@SteelEye.com>
Date: Tue, 02 Jan 2007 17:34:18 -0600

> Erm ... for a device driver, if we're preparing to do I/O on the page
> something must have made the user caches coherent ... that can't be
> kmap, because the driver might elect to DMA on the page ... unless
> another component of this API is going to be to make dma_map_... also
> flush the user cache?

The DMA map/unmap/sync performs the necessary cache flushes.
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