From owner-freebsd-hackers  Wed Jan 22 00:40:22 1997
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Date: Wed, 22 Jan 1997 19:36:11 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199701220836.TAA10401@godzilla.zeta.org.au>
To: current@freebsd.org, hackers@freebsd.org, sysseh@devetir.qld.gov.au
Subject: Re: Mmaping device space into user space
Sender: owner-hackers@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

>I'm fooling around with some of the sound device drivers, and I'm wanting to 
>know how to mmap some of the DMA buffers that they use into user space. Any 
>clues?

See scmmap() in syscons.c.  Mmaping in device drivers is very easy if the
memory is contiguous, page-aligned and never freed.

Bruce