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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,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 1936FECE58D for ; Wed, 9 Oct 2019 17:12:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DB75720B7C for ; Wed, 9 Oct 2019 17:12:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="bKd8BnYR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731862AbfJIRMW (ORCPT ); Wed, 9 Oct 2019 13:12:22 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:44272 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731433AbfJIRMW (ORCPT ); Wed, 9 Oct 2019 13:12:22 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x99H4RRg042492; Wed, 9 Oct 2019 17:11:58 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2019-08-05; bh=D4ahQEa/3t7Vqczl0GG7OBaPn9wEXOpVUYF/xsTU20A=; b=bKd8BnYRSWqER8g5IqufuZVLV802nfphh27t2+XxSYmCHFbpLwbSc6FpmwFlMWdf7hXk 2yEtCe3OGKV7uzoChJZqFZ2XExzaXLKPmQpnRnVmqAHSMRYdJjzzBgz8srQxYHpQ+ahq w2me6MDEGYOVFL32hsWoSBdirHCLRCQTJn92Qb9JpTSZbWi/iqiEV4lE6/aMGmk7GbmU jG/8Usa9cTzrTlq3GCTDZnUYHMaSdTldfLDyiLAWrXxb5AsDMQSvMjRFsyUwIVbjxQvt Nh7YNO01hlG0o3aaS9kxjTjfKjQC5+/7JHZqYxCLKd9jwzk9eab9//tpOerSohV4PVrn +Q== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2120.oracle.com with ESMTP id 2vektrnvmw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 09 Oct 2019 17:11:58 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x99H42uk196304; Wed, 9 Oct 2019 17:11:57 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3030.oracle.com with ESMTP id 2vh8k15e76-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 09 Oct 2019 17:11:57 +0000 Received: from abhmp0006.oracle.com (abhmp0006.oracle.com [141.146.116.12]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x99HBswv025543; Wed, 9 Oct 2019 17:11:55 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 09 Oct 2019 10:11:54 -0700 Date: Wed, 9 Oct 2019 10:11:52 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: Shiyang Ruan , linux-xfs@vger.kernel.org, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, rgoldwyn@suse.de, gujx@cn.fujitsu.com, david@fromorbit.com, qi.fuli@fujitsu.com, caoj.fnst@cn.fujitsu.com Subject: Re: [RFC PATCH 0/7] xfs: add reflink & dedupe support for fsdax. Message-ID: <20191009171152.GF13108@magnolia> References: <20190731114935.11030-1-ruansy.fnst@cn.fujitsu.com> <20191009063144.GA4300@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191009063144.GA4300@infradead.org> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9405 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=843 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910090148 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9405 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=930 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910090148 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 08, 2019 at 11:31:44PM -0700, Christoph Hellwig wrote: > Btw, I just had a chat with Dan last week on this. And he pointed out > that while this series deals with the read/write path issues of > reflink on DAX it doesn't deal with the mmap side issue that > page->mapping and page->index can point back to exactly one file. > > I think we want a few xfstests that reflink a file and then use the > different links using mmap, as that should blow up pretty reliably. Hmm, you're right, we don't actually have a test that checks the behavior of mwriting all copies of a shared block. Ok, I'll go write one. --D