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Date: Thu, 3 Jul 2008 23:26:34 -0400 (EDT)
From: Mikulas Patocka <mpatocka@redhat.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
cc: Jens Axboe <jens.axboe@oracle.com>, linux-kernel@vger.kernel.org,
       Neil Brown <neilb@suse.de>
Subject: Re: [PATCH 1/2] Avoid bio_endio recursion
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On Fri, 4 Jul 2008, Alan Cox wrote:

>
>> But not for SATA disks. The only thing SCSI and SATA disk have common is
>> that they may process concurrently more requests. There's nothing else.
>
> The only material difference between SATA and SCSI is the encoding of the
> command blocks and responses.
>
> Alan

That statement is true for any two block device protocol. Then, why 
doesn't Linux use SCSI for all block devices? --- add scsi command block 
to struct bio and we can pass them directly to controller driver :)

Mikulas