Messages in this thread |  | | From | "H. Peter Anvin" <> | Subject | Re: hammer: MAP_32BIT | Date | 9 May 2003 11:11:15 -0700 |
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Followup to: <20030509113845.GA4586@averell> By author: Andi Kleen <ak@muc.de> In newsgroup: linux.dev.kernel > > > On Fri, May 09, 2003 at 01:28:11PM +0200, mikpe@csd.uu.se wrote: > > I have a potential use for mmap()ing in the low 4GB on x86_64. > > Just use MAP_32BIT > > > Sounds like your MAP_32BIT really is MAP_31BIT :-( which is too limiting. > > What about a more generic way of indicating which parts of the address > > space one wants? The simplest that would work for me is a single byte > > 'nrbits' specifying the target address space as [0 .. 2^nrbits-1]. > > This could be specified on a per-mmap() basis or as a settable process attribute. > > On x86-64 an mmap extension for that would be fine, but on i386 you get > problems because mmap64() already maxes out the argument limit and you > cannot add more. >
How about this: since the address argument is basically unused anyway unless MAP_FIXED is set, how about a MAP_MAXADDR which interprets the address argument as the highest permissible address (or lowest nonpermissible address)?
-hpa -- <hpa@transmeta.com> at work, <hpa@zytor.com> in private! "Unix gives you enough rope to shoot yourself in the foot." Architectures needed: ia64 m68k mips64 ppc ppc64 s390 s390x sh v850 x86-64 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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