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Date:      Fri, 18 Sep 1998 14:48:33 -0400 (EDT)
From:      Scott Smyth <smyth@bashful.realminfo.com>
To:        Steve Friedrich <SteveFriedrich@Hot-Shot.com>
Cc:        freebsd-questions <freebsd-questions@FreeBSD.ORG>
Subject:   Re: memory allocation above "physical" memory (fwd)
Message-ID:  <Pine.LNX.3.96.980918144009.606N-100000@bashful.realminfo.com>
In-Reply-To: <199809181817.OAA10242@laker.net>

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On Fri, 18 Sep 1998, Steve Friedrich wrote:

> On Fri, 18 Sep 1998 12:08:45 -0400 (EDT), Scott Smyth wrote:
> 
> >Subject: memory allocation above "physical" memory
> >
> >The example: physical memory the kernel knows: 64 MB, but the
> >real memory banks hold 96 MB.  How can I access the top 32 MB?
> >Does functionality exist for:
> >1) getting page tables;
> >2) mapping page tables to virtual addresses.
> >
> 
> Would you be interested in the kernel detecting that 32MB ??
> Look in the LINT config is /sys/i386/conf for MAXMEM.  There are notes
> regarding usage...
> 

Yes.  I use that already too.  I am talking a way to allocate
pages and memory outside of the regular kernel mapping for my
own purposes.  I am going to try and allocate the memory
treating it like a device (/dev/exmem like /dev/mem) pages using
d_mmap.  That way I can access them without any other OS
"interference" if you will for my own special buffer use.

Thanks

-- 
Scott Smyth, Senior Developer R&D
(770) 446-1332
ssmyth@realminfo.com


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