From owner-freebsd-current@FreeBSD.ORG Tue Oct 10 18:09:36 2006 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id D258C16A403; Tue, 10 Oct 2006 18:09:36 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [209.31.154.42]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7786943D79; Tue, 10 Oct 2006 18:09:36 +0000 (GMT) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [209.31.154.41]) by cyrus.watson.org (Postfix) with ESMTP id E160A46B08; Tue, 10 Oct 2006 14:09:35 -0400 (EDT) Date: Tue, 10 Oct 2006 19:09:36 +0100 (BST) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: Daichi GOTO In-Reply-To: <452BA8C4.7040906@freebsd.org> Message-ID: <20061010190815.L92182@fledge.watson.org> References: <452BA8C4.7040906@freebsd.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: freebsd-fs@freebsd.org, freebsd-hackers@freebsd.org, freebsd-current@freebsd.org, ozawa@ongs.co.jp, rodrigc@crodrigues.org Subject: Re: [REQUEST] unionfs needs some guys can do implements new 2 APIs for VFS X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 Oct 2006 18:09:36 -0000 On Tue, 10 Oct 2006, Daichi GOTO wrote: > 1 Introduction > > We have always tried to keep changes just in unionfs segment > only. But by accomplish nothing, we need change the other segment. > > > 2 Problem Description > > Until now we have did many improvements for unionfs, but > now we feel the limication arount the process of unionfs's > "copied-up file". Additional thinking of future support for > MAC extention, ADVLOCK lock infomation and somethinkg like those, > all the more reason to be careful. > > 3 Impact > > It leads the confution of unionfs implementation and some > problem around lock mechanism. We cannot solve those problem > by just only changes in unionfs segument. So, just to be clear that I understand things: the basic problem here is that when unionfs copies a file up a layer in the stack due to local modifications in the upper layer, you are not able to properly preserve the full set of file attributes, so are looking for a way to do this? Robert N M Watson Computer Laboratory University of Cambridge