From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id 036536810C3 for ; Fri, 25 Aug 2017 12:25:40 -0400 (EDT) Received: by mail-wr0-f198.google.com with SMTP id y14so408703wrd.3 for ; Fri, 25 Aug 2017 09:25:39 -0700 (PDT) Received: from mout.gmx.net (mout.gmx.net. [212.227.17.21]) by mx.google.com with ESMTPS id j64si1537750wmd.63.2017.08.25.09.25.38 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 25 Aug 2017 09:25:38 -0700 (PDT) Subject: Re: [PATCH v6 3/5] mm: introduce mmap3 for safely defining new mmap flags References: <150353211413.5039.5228914877418362329.stgit@dwillia2-desk3.amr.corp.intel.com> <150353213097.5039.6729469069608762658.stgit@dwillia2-desk3.amr.corp.intel.com> <20170824165546.GA3121@infradead.org> <20170825130011.GA30072@infradead.org> <20170825155803.4km7wttzadfqw2vb@node.shutemov.name> <20170825160236.GA2561@infradead.org> <20170825161607.6v6beg4zjktllt2z@node.shutemov.name> From: Helge Deller Message-ID: <4de21e8d-5e10-ec40-c731-0c079953cf48@gmx.de> Date: Fri, 25 Aug 2017 18:19:19 +0200 MIME-Version: 1.0 In-Reply-To: <20170825161607.6v6beg4zjktllt2z@node.shutemov.name> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" , Christoph Hellwig Cc: Dan Williams , Andrew Morton , Jan Kara , Arnd Bergmann , "linux-nvdimm@lists.01.org" , Linux API , "linux-kernel@vger.kernel.org" , linux-xfs@vger.kernel.org, Linux MM , Andy Lutomirski , linux-fsdevel , "Kirill A. Shutemov" , linux-parisc@vger.kernel.org On 25.08.2017 18:16, Kirill A. Shutemov wrote: > On Fri, Aug 25, 2017 at 09:02:36AM -0700, Christoph Hellwig wrote: >> On Fri, Aug 25, 2017 at 06:58:03PM +0300, Kirill A. Shutemov wrote: >>> Not all archs are ready for this: >>> >>> arch/parisc/include/uapi/asm/mman.h:#define MAP_TYPE 0x03 /* Mask for type of mapping */ >>> arch/parisc/include/uapi/asm/mman.h:#define MAP_FIXED 0x04 /* Interpret addr exactly */ >> >> I'd be happy to say that we should not care about parisc for >> persistent memory. We'll just have to find a way to exclude >> parisc without making life too ugly. > > I don't think creapling mmap() interface for one arch is the right way to > go. I think the interface should be universal. > > I may imagine MAP_DIRECT can be useful not only for persistent memory. > For tmpfs instead of mlock()? On parisc we have #define MAP_SHARED 0x01 /* Share changes */ #define MAP_PRIVATE 0x02 /* Changes are private */ #define MAP_TYPE 0x03 /* Mask for type of mapping */ #define MAP_FIXED 0x04 /* Interpret addr exactly */ #define MAP_ANONYMOUS 0x10 /* don't use a file */ So, if you need a MAP_DIRECT, wouldn't e.g. #define MAP_DIRECT 0x08 be possible (for parisc, and others 0x04). And if MAP_TYPE needs to include this flag on parisc: #define MAP_TYPE (0x03 | 0x08) /* Mask for type of mapping */ Helge -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org