From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261226AbUBTOAQ (ORCPT ); Fri, 20 Feb 2004 09:00:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261229AbUBTOAN (ORCPT ); Fri, 20 Feb 2004 09:00:13 -0500 Received: from mx2.elte.hu ([157.181.151.9]:10450 "EHLO mx2.elte.hu") by vger.kernel.org with ESMTP id S261237AbUBTN7V (ORCPT ); Fri, 20 Feb 2004 08:59:21 -0500 Date: Fri, 20 Feb 2004 15:00:25 +0100 From: Ingo Molnar To: Jamie Lokier Cc: Linus Torvalds , Tridge , Al Viro , "H. Peter Anvin" , Kernel Mailing List Subject: Re: explicit dcache <-> user-space cache coherency, sys_mark_dir_clean(), O_CLEAN Message-ID: <20040220140025.GA13381@elte.hu> References: <20040219081027.GB4113@mail.shareable.org> <20040219163838.GC2308@mail.shareable.org> <20040219182948.GA3414@mail.shareable.org> <20040220120417.GA4010@elte.hu> <20040220131932.GB8994@mail.shareable.org> <20040220133707.GA11773@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040220133707.GA11773@elte.hu> User-Agent: Mutt/1.4.1i X-ELTE-SpamVersion: MailScanner-4.26.8-itk2 SpamAssassin 2.63 ClamAV 0.65 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org for Samba, the use of sys_mark_dir_clean() & O_CLEAN would be that it could fully cache all namespace data in user-space (as it already does), and could assume that the userspace cache is uptodate and ensure that a particular name does not exist - under whatever namespace rules it wants to use. create(O_CLEAN) will return with -EFLUSH if this assumption is not true anymore - in which case it can re-read that directory. this way the fastpath would not involve any readdir() calls at all - even in a mixed environment. Ingo