Return-Path: Received: from fn.samba.org ([216.83.154.106]:45902 "EHLO lists.samba.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755601Ab0HEXwb (ORCPT ); Thu, 5 Aug 2010 19:52:31 -0400 Date: Thu, 5 Aug 2010 16:52:18 -0700 From: Jeremy Allison To: Jeff Layton Cc: utz lehmann , Linus Torvalds , Jeremy Allison , Volker.Lendecke@sernet.de, David Howells , Jan Engelhardt , linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk, linux-fsde@jasper.es Subject: Re: [PATCH 02/18] xstat: Add a pair of system calls to make extended file stats available [ver #6] Message-ID: <20100805235218.GB31233@jeremy-laptop> Reply-To: Jeremy Allison References: <20100715021709.5544.64506.stgit@warthog.procyon.org.uk> <20100715021712.5544.44845.stgit@warthog.procyon.org.uk> <30448.1279800887@redhat.com> <1280524978.2452.9.camel@segv.aura.of.mankind> <20100801092529.5e6ba0e0@corrin.poochiereds.net> Content-Type: text/plain; charset=us-ascii In-Reply-To: <20100801092529.5e6ba0e0@corrin.poochiereds.net> Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On Sun, Aug 01, 2010 at 09:25:29AM -0400, Jeff Layton wrote: > On Fri, 30 Jul 2010 23:22:58 +0200 > utz lehmann wrote: > > > On Thu, 2010-07-22 at 09:40 -0700, Linus Torvalds wrote: > > > But the fact is, th Unix ctime semantics are insane and largely > > > useless. There's a damn good reason almost nobody uses ctime under > > > unix. > > > > > > So what I'm suggesting is that we have a flag - either per-process or > > > per-mount - that just says "use windows semantics for ctime". > > > > When abusing an existing time stamp use atime not ctime please. > > ctime has it's uses. atime was just a mistake and is nearly useless. > > > > And with noatime we already have creation time semantics for atime. > > > > Ugh. Honestly all of this talk of abusing different time fields seems > like craziness to me. It's going to be very hard to do that without > breaking *something*. There's also very little reason to do this when > xattrs are a much cleaner approach. > > Neil Brown has put forth a very reasoned justification for putting the > birthtime in an xattr. After reading it, I think that makes more sense > than anything. It's also something that can be done without any extra > infrastructure. If at some point in the future we get an xstat-like > syscall then we can always add birthtime to that as well. Just my 2 cents (as a Samba server implementor). I *hate* the idea of adding a "virtual" EA for birthtime. If you're going to add it, just add it to the stat struct like *BSD does. Don't abuse the other time fields, it's a new one. Jeff, please don't advocate for an EA for the Samba server to use. Don't add it as an EA. It's *not* an EA, it's a timestamp. Jeremy.