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To: "David S. Miller" <davem@redhat.com>
cc: andrea@suse.de, linux-kernel@vger.kernel.org
Subject: Re: mincore on anon mappings
References: <28R2T-8ld-13@gated-at.bofh.it> <28Tev-1Bm-23@gated-at.bofh.it>
From: Andi Kleen <ak@muc.de>
Date: Sun, 20 Jun 2004 02:05:19 +0200
In-Reply-To: <28Tev-1Bm-23@gated-at.bofh.it> (David S. Miller's message of
 "Sat, 19 Jun 2004 21:00:15 +0200")
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"David S. Miller" <davem@redhat.com> writes:

>
> Therefore I propose we add a MAP_FORCE which does exactly what GCC wants
> which is:
>
> 1) The passed in 'hint' address is treated as mandatory, if exactly that
>    address cannot be used, we fail.
>
> 2) Existing areas get in the way, and cause failure.

That sounds unintuitive. I would expect MAP_FORCE to do exactly
that (that is is done by default right now is a different story).
But you want to reverse the meaning.

How about calling it MAP_STRICT or just MAP_CHECK ? 

>
> 3) get_unmapped_area() implementations shut off any 'hint' address
>    modification logic they may have.

Good idea definitely.


-Andi