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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 A3FEAC433E2 for ; Mon, 31 Aug 2020 14:46:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 828332083E for ; Mon, 31 Aug 2020 14:46:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="HPY3lwom" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728109AbgHaOqX (ORCPT ); Mon, 31 Aug 2020 10:46:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726948AbgHaOqC (ORCPT ); Mon, 31 Aug 2020 10:46:02 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BA33C061575 for ; Mon, 31 Aug 2020 07:46:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=uN9Ii7LwRnIVqWqYpXM2y6R/htpHOxiLuPI7LAVAu9I=; b=HPY3lwom0COfnDdfEVj3T2j18G 28fjOZ7uanwOWWtfZjC+485PQmb/AFejhJUQRSoe5PaRIt9xJI1VDN4SXhK3vYfPbnsekK8Pzjgti ZEUjIKarX6RAn6Y7IImUiUiii+Eh/Yx73V+dd9NjMxKYX/Af9EFQXaw3co7HD4rS8rm/HmeBEoVpT Bfj/l44EdBJjlSwanec3FiU9g1UCnbPTBs8Y29PGgmN72imu+BW7VROLG1L3KWcQ8cMPp8ERFIQyZ YzNOvun0fjf2kRYRc+hhwzyL59IsnaNRw50VzboV40U5TDOrXFkxBITXj1EVsZzVRruXrzjsrDK8g 83ZYs6og==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kCl4F-0005Dv-1P; Mon, 31 Aug 2020 14:45:55 +0000 Date: Mon, 31 Aug 2020 15:45:54 +0100 From: Matthew Wilcox To: "Theodore Y. Ts'o" Cc: Miklos Szeredi , Al Viro , Dave Chinner , "Dr. David Alan Gilbert" , Greg Kurz , linux-fsdevel@vger.kernel.org, Stefan Hajnoczi , Miklos Szeredi , Vivek Goyal , Giuseppe Scrivano , Daniel J Walsh , Chirantan Ekbote Subject: Re: xattr names for unprivileged stacking? Message-ID: <20200831144554.GF14765@casper.infradead.org> References: <20200829180448.GQ1236603@ZenIV.linux.org.uk> <20200829192522.GS1236603@ZenIV.linux.org.uk> <20200830191016.GZ14765@casper.infradead.org> <20200831113705.GA14765@casper.infradead.org> <20200831132339.GD14765@casper.infradead.org> <20200831142532.GC4267@mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200831142532.GC4267@mit.edu> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, Aug 31, 2020 at 10:25:32AM -0400, Theodore Y. Ts'o wrote: > Oh, one other question about ADS; if a file system supports reflink, > what is supposed to happen when you reflink a file? You have to > consider all of the ADS's to be reflinked as well? In some ways, this > is good, because the overhead and complexity will probably cause most > file system maintainers to throw up their had, say this is madness, > and refuse to implement it. :-) Why is it so much harder than reflinking all the xattrs on a file? If one thinks that Miklos' crazypants infinite hierarchy is the way to go, then yes, this is absurdly complex. If these are closer in spirit to being seekable xattrs, then it looks a lot more managable.