Date: Thu, 25 Jun 2009 10:46:41 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: "Martin K. Petersen" <martin.petersen@oracle.com>
cc: NeilBrown <neilb@suse.de>, Mike Snitzer <snitzer@redhat.com>,
       Alasdair G Kergon <agk@redhat.com>, jens.axboe@oracle.com,
       linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
       linux-raid@vger.kernel.org, linux-ide@vger.kernel.org,
       linux-fsdevel@vger.kernel.org,
       device-mapper development <dm-devel@redhat.com>
Subject: Re: [dm-devel] REQUEST for new 'topology' metrics to be moved out 
 of the 'queue' sysfs directory.
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On Thu, 25 Jun 2009, Martin K. Petersen wrote:
> 
> Neil> So I asked git why it as added, and it pointed to
> Neil>   commit 1308835ffffe6d61ad1f48c5c381c9cc47f683ec
> 
> Neil> which suggests that it was added so that user space could tell the
> Neil> kernel whether the device was rotational, rather than the other
> Neil> way around.
> 
> There's an option to do it via udev for broken devices that don't report
> it.  But both SCSI and ATA have a setting that gets queried and the
> queue flag set accordingly.

.. except few devices actually set it. 

That flag is _definitely_ all about the user being able to override it.

		Linus
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