From owner-freebsd-arch@FreeBSD.ORG  Mon Jun 26 09:16:22 2006
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To: Robert Watson <rwatson@FreeBSD.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 26 Jun 2006 09:15:42 +0100."
	<20060626090937.U24406@fledge.watson.org> 
Date: Mon, 26 Jun 2006 08:50:09 +0000
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Cc: John-Mark Gurney <gurney_j@resnet.uoregon.edu>,
	Pawel Jakub Dawidek <pjd@FreeBSD.org>, freebsd-arch@freebsd.org
Subject: Re: Accessing disks via their serial numbers. 
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In message <20060626090937.U24406@fledge.watson.org>, Robert Watson writes:

>Yes -- one of the problems/benefits of the disk(9) API is that it's a very 
>narrow API.  I'd like to see an attribute API pushed into disk(9) so that GEOM 
>modules can query additional disk properties in much the same way they can 
>query GEOM attributes.

I'm not against this, I just don't want to do it more than once :-)

>GEOM univerally provides similar 
>guarantees, such as sectorsize not changing.  Media size is a slightly more 
>dubious one, of course, and probably should become variable.

Mediasize and sectorsize are only (required to be) constant while
the device is held open.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.