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=-8.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 39F5DC8300F for ; Tue, 1 Dec 2020 19:25:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E8D742168B for ; Tue, 1 Dec 2020 19:25:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="G1uFtDqk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404368AbgLATYe (ORCPT ); Tue, 1 Dec 2020 14:24:34 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:37755 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404354AbgLATY3 (ORCPT ); Tue, 1 Dec 2020 14:24:29 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1606850583; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WOvlm/2by5V81YbdnYUcfCHCjbYXKTUV3qAl9vLT98w=; b=G1uFtDqkAWLjUhX5soPnDtOXIu9pfE7IBTaSi/py0Pbh1P7ASH9jQay15jvjzUrEYkW185 f53kO/xF1rVpE52Rd1qemkAn76Rf4bn9w+7MaWoBmoQUi4S22LX8zPWSNwjxLsg1bZFamb rjdTgrRyOZOetyeLCyz8vGCuNo1RgOs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-366-moM0juacPHuFCfBqqoTWVQ-1; Tue, 01 Dec 2020 14:23:01 -0500 X-MC-Unique: moM0juacPHuFCfBqqoTWVQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 792CD8558E8 for ; Tue, 1 Dec 2020 19:23:00 +0000 (UTC) Received: from liberator.sandeen.net (ovpn04.gateway.prod.ext.phx2.redhat.com [10.5.9.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 505B65D9CA for ; Tue, 1 Dec 2020 19:23:00 +0000 (UTC) Subject: Re: [PATCH 0/2] xfs: fix up some reflink+dax interactions From: Eric Sandeen To: xfs References: <1d87a83e-ba03-b735-f19a-955a09bcdcf7@redhat.com> Message-ID: <7680868b-d804-faf2-9fbd-f03ca8a69fdd@redhat.com> Date: Tue, 1 Dec 2020 13:23:00 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <1d87a83e-ba03-b735-f19a-955a09bcdcf7@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On 12/1/20 1:10 PM, Eric Sandeen wrote: > dax behavior has changed semi-recently, most notably that per-inode dax > flags are back, which opens the possibility of dax-capable files existing on > reflink-capable filesystems. > > While we still have a reflink-vs-dax-on-the-same-file incompatibilty, and for > the most part this is handled correctly, there are a couple of known issues: > > 1) xfs_dinode_verify will trap an inode with reflink+dax flags as corrupted; > this needs to be removed, because we actually can get into this state today, > and eventually that state will be supported in future kernels. > > 2) (more RFC) until we actually support reflink+dax files, perhaps we should > prevent the flags from co-existing in a kernel that cannot support both > states. patch 2 stops us from reflinking files with the dax flag set, > whether or not the file is actually "in the CPU direct access state" > > -Eric Also yes I owe xfstests for these but wanted to see if the patches fly, first. -Eric