From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751192AbVIDFuD (ORCPT ); Sun, 4 Sep 2005 01:50:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751207AbVIDFuD (ORCPT ); Sun, 4 Sep 2005 01:50:03 -0400 Received: from rgminet02.oracle.com ([148.87.122.31]:52562 "EHLO rgminet02.oracle.com") by vger.kernel.org with ESMTP id S1751192AbVIDFt7 (ORCPT ); Sun, 4 Sep 2005 01:49:59 -0400 Date: Sat, 3 Sep 2005 22:49:37 -0700 From: Joel Becker To: linux clustering Cc: phillips@istop.com, linux-fsdevel@vger.kernel.org, ak@suse.de, linux-kernel@vger.kernel.org Subject: Re: [Linux-cluster] Re: GFS, what's remaining Message-ID: <20050904054936.GW8684@ca-server1.us.oracle.com> Mail-Followup-To: linux clustering , phillips@istop.com, linux-fsdevel@vger.kernel.org, ak@suse.de, linux-kernel@vger.kernel.org References: <20050901104620.GA22482@redhat.com> <20050903183241.1acca6c9.akpm@osdl.org> <20050904030640.GL8684@ca-server1.us.oracle.com> <200509040022.37102.phillips@istop.com> <20050903214653.1b8a8cb7.akpm@osdl.org> <20050904045821.GT8684@ca-server1.us.oracle.com> <20050903224140.0442fac4.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050903224140.0442fac4.akpm@osdl.org> X-Burt-Line: Trees are cool. X-Red-Smith: Ninety feet between bases is perhaps as close as man has ever come to perfection. User-Agent: Mutt/1.5.10i X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 03, 2005 at 10:41:40PM -0700, Andrew Morton wrote: > Are you saying that the posix-file lookalike interface provides access to > part of the functionality, but there are other APIs which are used to > access the rest of the functionality? If so, what is that interface, and > why cannot that interface offer access to 100% of the functionality, thus > making the posix-file tricks unnecessary? Currently, this is all the interface that the OCFS2 DLM provides. But yes, if you wanted to provide the rest of the VMS functionality (something that GFS2's DLM does), you'd need to use a more concrete interface. IMHO, it's worthwhile to have a simple interface, one already used by mkfs.ocfs2, mount.ocfs2, fsck.ocfs2, etc. This is an interface that can and is used by shell scripts even (we do this to test the DLM). If you make it a C-library-only interface, you've just restricted the subset of folks that can use it, while adding programming complexity. I think that a simple fs-based interface can coexist with a more complex one. FILE* doesn't give you the flexibility of read()/write(), but I wouldn't remove it :-) Joel -- "In the beginning, the universe was created. This has made a lot of people very angry, and is generally considered to have been a bad move." - Douglas Adams Joel Becker Senior Member of Technical Staff Oracle E-mail: joel.becker@oracle.com Phone: (650) 506-8127