From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1DB03C71155 for ; Tue, 1 Dec 2020 03:12:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6518F20725 for ; Tue, 1 Dec 2020 03:12:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fieldses.org header.i=@fieldses.org header.b="IqPun1Z4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727303AbgLADMM (ORCPT ); Mon, 30 Nov 2020 22:12:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53974 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725859AbgLADML (ORCPT ); Mon, 30 Nov 2020 22:12:11 -0500 Received: from fieldses.org (fieldses.org [IPv6:2600:3c00:e000:2f7::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9BE15C0613CF for ; Mon, 30 Nov 2020 19:11:31 -0800 (PST) Received: by fieldses.org (Postfix, from userid 2815) id 3FAE86F4A; Mon, 30 Nov 2020 22:11:30 -0500 (EST) DKIM-Filter: OpenDKIM Filter v2.11.0 fieldses.org 3FAE86F4A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fieldses.org; s=default; t=1606792290; bh=KjdfVVQGHz1pqiDdxN52V4QbZ29aTlUAGPf2WdluaoQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IqPun1Z4EqPD7FyQF1itBMQOvNC9IkoD+S4wVPGk7/gNHQE/TuO9+ygB4z6TzjkEu 7w9ODCq+YTqW8PjaKHQWgVZKPYPZjCmiV0WcZqRjQITvzv2Tdzq6+EDXYji+pbwWHG X7MRtYGCG4gdi+1IqPvRKuebmvtlbckhLEmymJdw= Date: Mon, 30 Nov 2020 22:11:30 -0500 From: "bfields@fieldses.org" To: Trond Myklebust Cc: "bfields@redhat.com" , "linux-nfs@vger.kernel.org" , "chuck.lever@oracle.com" Subject: Re: [PATCH 1/6] nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations Message-ID: <20201201031130.GD22446@fieldses.org> References: <20201130212455.254469-1-trondmy@kernel.org> <20201130212455.254469-2-trondmy@kernel.org> <20201130225842.GA22446@fieldses.org> <1b525278a9a7541529290588a83852a0754cee3e.camel@hammerspace.com> <20201201022834.GA241188@pick.fieldses.org> <66f93208c6edf2dad70ee41c349c5130b30b8ed4.camel@hammerspace.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <66f93208c6edf2dad70ee41c349c5130b30b8ed4.camel@hammerspace.com> User-Agent: Mutt/1.5.21 (2010-09-15) Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Tue, Dec 01, 2020 at 03:06:46AM +0000, Trond Myklebust wrote: > A local filesystem might choose to set the 'non-atomic' flag without > wanting to turn off NFSv3 WCC attributes. Yes, the latter are assumed > to be atomic, but a number of commercial servers do abuse that > assumption in practice. What do you mean by abusing that assumption? I thought that leaving off the post-op attrs was the v3 protocol's way of saying that it couldn't give you atomic wcc information. --b.