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Date: Tue, 1 Feb 2011 12:56:08 -0500
From: Christoph Hellwig <hch@infradead.org>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>, Amerigo Wang <amwang@redhat.com>,
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        David Woodhouse <David.Woodhouse@intel.com>,
        Andy Fleming <afleming@freescale.com>,
        "David S. Miller" <davem@davemloft.net>
Subject: Re: [RFC Patch] virtio: export model and type in /sys
Message-ID: <20110201175608.GA28913@infradead.org>
References: <1296442381-21652-1-git-send-email-amwang@redhat.com>
 <20110201173738.GA18526@infradead.org>
 <20110201174607.GA24924@redhat.com>
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On Tue, Feb 01, 2011 at 07:46:07PM +0200, Michael S. Tsirkin wrote:
> ide seems to export these too.
> 
> $ cat /sys/class/block/sr0/device/model 
> DVDRAM GSA-U20N 
> 
> and I am pretty sure my dvd isn't scsi ...

And I'm pretty sure it is, not just in one but two different ways.
For one all ATA attached CDROMS are ATAPI, which just means a SCSI
command set (MMC in this case) tunneled over an ATA transport.  Second
libata always is a scsi low level driver, even when talking to ATA
disk, it just responds to the SCSI commands by translating them to
equivalent ATA commands or faking them up.