From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: adding proper O_SYNC/O_DSYNC, was Re: O_DIRECT and barriers Date: Fri, 28 Aug 2009 17:08:38 -0400 Message-ID: <20090828210838.GA26799@infradead.org> References: <20090824023422.GA775@infradead.org> <20090827143459.GB31453@shareable.org> <20090827171044.GA5427@infradead.org> <4A96C14C.8040105@redhat.com> <20090828154647.GA15808@infradead.org> <4A98008B.6050503@redhat.com> <20090828161745.GA8755@infradead.org> <4A9806D9.5050409@redhat.com> <20090828164106.GA9951@infradead.org> <4A984337.7080009@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Christoph Hellwig , Jamie Lokier , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org To: Ulrich Drepper Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:45600 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751134AbZH1VIj (ORCPT ); Fri, 28 Aug 2009 17:08:39 -0400 Content-Disposition: inline In-Reply-To: <4A984337.7080009@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Fri, Aug 28, 2009 at 01:51:03PM -0700, Ulrich Drepper wrote: > No, that's not a good idea. This would mean a program compiled with > newer headers is using O_SYNC which isn't known to old kernels and > ignored. Such programs will then not even get the current O_DSYNC > benefits. Ok, let's agree on how to proceed: once 2.6.31 is out we will do the following - do a global s/O_SYNC/O_DSYNC/g over the whole kernel tree - add a this to include/asm-generic/fcntl.h and in modified form to arch headers not using it: #ifndef O_FULLSYNC #define O_FULLSYNC 02000000 #endif #ifndef O_RSYNC #define O_RSYNC 04000000 #endif #define O_SYNC (O_FULLSYNC|O_DSYNC) - during the normal merge window I will add a real implementation for for O_FULLSYNC and O_RSYNC P.S. better naming suggestions for O_FULLSYNC welcome