From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753935Ab3LQNvc (ORCPT ); Tue, 17 Dec 2013 08:51:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49117 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752726Ab3LQNv3 (ORCPT ); Tue, 17 Dec 2013 08:51:29 -0500 Date: Tue, 17 Dec 2013 08:50:55 -0500 From: Jeff Layton To: Christoph Hellwig Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, nfs-ganesha-devel@lists.sourceforge.net, samba-technical@lists.samba.org Subject: Re: [PATCH v3 6/6] locks: add new "private" lock type that is owned by the filp Message-ID: <20131217085055.1e89965c@tlielax.poochiereds.net> In-Reply-To: <20131217133721.GA16724@infradead.org> References: <1386703055-22308-1-git-send-email-jlayton@redhat.com> <1386703055-22308-7-git-send-email-jlayton@redhat.com> <20131217083125.4ce0382b@tlielax.poochiereds.net> <20131217133721.GA16724@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 17 Dec 2013 05:37:21 -0800 Christoph Hellwig wrote: > On Tue, Dec 17, 2013 at 08:31:25AM -0500, Jeff Layton wrote: > > So, I think the above semantics are pretty clear, but now that I've had > > a go at sitting down to document this stuff for the POSIX spec and > > manpages, it's clear how convoluted the text in there is becoming. > > > > That makes me wonder...would we be better off with a new set of cmd > > values here instead of new l_type values? IOW, we could add new: > > > > F_GETLKP > > F_SETLKP > > F_SETLKPW > > That seems a tad cleaner to me indeed. > > > ...and then just reuse the same F_RDLCK/F_WRLCK/F_UNLCK values? With > > that too, we could create a new equivalent to struct flock that has > > fixed length types instead of dealing with the off_t mess. > > For the Posix interface you'd need an off_t as that's what the whole > API uses for file offsets. We could make sure to always use a off64_t > for the kernel interface though. > Ok. > What is the API you propose to posix? An new posix_lockf? > I haven't proposed anything concrete to POSIX just yet. I'm trying to get the Linux patches done and then I'll do that. I don't think we want a new syscall when fcntl() will work. If we use new cmd values however, then we don't necessarily need to use struct flock/flock64. I think the question is -- should we stick with struct flock/flock64, or would we be better served with something new for this? Thanks, -- Jeff Layton