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Date: Fri, 09 Apr 2010 17:29:27 +0300
From: Andriy Gapon <avg@freebsd.org>
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To: Scott Long <scottl@samsco.org>
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Cc: arch@freebsd.org, Rick Macklem <rmacklem@uoguelph.ca>
Subject: Re: (in)appropriate uses for MAXBSIZE
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on 09/04/2010 16:52 Scott Long said the following:
> 
> Storage drivers are insulated from the details of MAXBSIZE by GEOM honoring
> the driver's advertised max-i/o-size attribute.  What I see when I grep through the
> sources are mostly uses in busdma attributes, which themselves probably came
> via cut-n-paste from prior drivers.  I can't come up with any explanation for that
> which makes good design sense, so I'll agree that storage drivers shouldn't
> reference MAXBSIZE.

Should DFLTPHYS be used there?
Or is there a better DMA-specific constant?
Or, perhaps, each driver should just use its won private constant based on its
hardware capabilities?

-- 
Andriy Gapon