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Subject: Re: [PATCH] 2.5.67-ac2 direct-IO for IDE taskfile ioctl (0/4)
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Andrew Morton <akpm@digeo.com>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>,
       Andre Hedrick <andre@linux-ide.org>, axboe@suse.de,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Date: 23 Apr 2003 23:09:47 +0100
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On Mer, 2003-04-23 at 23:35, Andrew Morton wrote:
> Dumb question: what does all this code actually do?
> 
> It appears to be implementing an IDE-specific ioctl() which performs bulk
> IO direct to/from userspace.  But that seems to be equivalent to O_DIRECT
> access to /dev/hda.
> 
> What is special about the IDE ioctl approach?

Think /dev/sg at the ATA level