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Date: Sat, 05 Sep 2009 08:42:25 +0300
From: Alexander Motin <mav@FreeBSD.org>
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To: Matthew Dillon <dillon@apollo.backplane.com>
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Cc: Ryan Rogers <webmaster@doghouserepair.com>, current@freebsd.org
Subject: Re: non aligned DMA transfer attempted
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Matthew Dillon wrote:
> :>    The physio code directly maps the userland buffer via vmapbuf() and
> :>    supplies it as a BIO to the device.  The ATA driver does not use
> :>    BUSDMA (and never has)... it assumes BIOs are minimally aligned.
> :
> :Wrong.
> 
>     By the way Scott, do you honestly believe that idiotic one-line
>     answers just as a means to try to screw over my postings are
>     appropriate for someone of your standing in the FreeBSD community?

His answer is short, but correct, because all ATA drivers do use BUSDMA.
And as I have already said, BUSDMA manages proper alignment there, by
implementing bounce buffers.

-- 
Alexander Motin