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Date: Fri, 13 Jul 2007 18:35:28 +0200
From: Jens Axboe <jens.axboe@oracle.com>
To: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Subject: Re: [patch 5/6] ps3: BD/DVD/CD-ROM Storage Driver
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Cc: James Bottomley <James.Bottomley@steeleye.com>,
	Arnd Bergmann <arnd@arndb.de>, linux-scsi@vger.kernel.org,
	linux-kernel@vger.kernel.org, Alessandro Rubini <rubini@vision.unipv.it>,
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On Fri, Jul 13 2007, Geert Uytterhoeven wrote:
> > It's probably a good idea to have the flush_kernel_dcache_page() in there
> > anyway, if only to serve as an example for people that copy it into
> > architecture-independent drivers, same as what we do for the
> > k{,un}map_atomic() that is also not required on ppc64.
> 
> Now my next question: why should I add it, if currently no single driver in
> mainline calls flush_kernel_dcache_page()? 
> 
> `git grep' finds it in the following files only:
>     Documentation/cachetlb.txt
>     arch/parisc/kernel/cache.c
>     arch/parisc/kernel/pacache.S
>     include/asm-parisc/cacheflush.h
>     include/linux/highmem.h

Not many drivers fiddle around with stuff like this, it's usually hidden
behind the dma api or in helpers.

-- 
Jens Axboe