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Date:      Tue, 26 Aug 1997 13:32:33 +0930
From:      Greg Lehey <grog@lemis.com>
To:        Mike Smith <mike@smith.net.au>
Cc:        Joerg Wunsch <joerg_wunsch@uriah.heep.sax.de>, "hackers@freebsd.org" <hackers@FreeBSD.ORG>, Mike Burgett <mburgett@awen.com>
Subject:   Re: special malloc needs...
Message-ID:  <19970826133233.19386@lemis.com>
In-Reply-To: <199708260352.NAA00731@word.smith.net.au>; from Mike Smith on Tue, Aug 26, 1997 at 01:22:50PM %2B0930
References:  <19970826124223.62337@lemis.com> <199708260352.NAA00731@word.smith.net.au>

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On Tue, Aug 26, 1997 at 01:22:50PM +0930, Mike Smith wrote:
>> On Mon, Aug 25, 1997 at 10:20:08PM +0200, J Wunsch wrote:
>>> As Mike Burgett wrote:
>>>
>>>> Is there any way to malloc memory (from userland code) that is at
>>>> specific offsets from each other in physical memory (i.e. 2 chunks
>>>> exactly XXM apart in physical RAM) or failing that, to allocate a
>>>> very large (>32M) chunk of contig physical RAM? (again, from
>>>> userland?)
>>>
>>> No, you can't do this.  You get virtual memory, nothing else.  It's
>>> not even backed with physical memory at all when you've got it.
>>
>> Well, you can't malloc() it, but you can try to mmap() it with
>> MAP_FIXED.  man mmap(2).
>
> This only gives you a fixed _virtual_ address.

Yes, it does.  That's what I thought he wanted.  Re-reading the
original message, I see I was wrong.  Mike (B), whatever do you want
to allocate physical memory for?

Greg



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