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=-0.9 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 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 E526AC4CECE for ; Mon, 16 Sep 2019 17:22:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BCA33214D9 for ; Mon, 16 Sep 2019 17:22:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="ZrCMRNMB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729670AbfIPRWR (ORCPT ); Mon, 16 Sep 2019 13:22:17 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:46928 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727593AbfIPRWR (ORCPT ); Mon, 16 Sep 2019 13:22:17 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x8GHJ1v8030790; Mon, 16 Sep 2019 17:19:55 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=to : cc : subject : from : references : date : in-reply-to : message-id : mime-version : content-type; s=corp-2019-08-05; bh=cv+DwWu9qoA7iqv3H2CpGW617J3RoXHp/vizYrY+tpY=; b=ZrCMRNMBnZlDrtqwP8+dWglJrV2cGcPJexJJOkZWUlOaXHwOmKWyhKw1v79KTFHsHQ4t tRVXhGRos4gX2mYvfqLgWKO69LEq7POoj/KBvsUozw6QIb6QVczGByQALTVGRfw3/rha 5/p3LEu9DDdm+xgb3qLe/tJYhSg0jER2apZMeGhZV2PoSTJcNu2DyA2mPwM99gaEt30b Lxu3sC2GzLh7h+pyG0ZbPtDpH5YV/3rkRky0wmMfwd7cPe6C28EKm6dQzQ0zmODPakJd RXiH+E6yQhjsE6mqvghJeXymtVoZE7Gg+Re5EX9L0rJ3Eq8hJuLRURKboZXZRsfSuhfG fw== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2130.oracle.com with ESMTP id 2v2bx2s5nd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 16 Sep 2019 17:19:55 +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 x8GHIngj084270; Mon, 16 Sep 2019 17:19:54 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3030.oracle.com with ESMTP id 2v0p8uwmbn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 16 Sep 2019 17:19:54 +0000 Received: from abhmp0006.oracle.com (abhmp0006.oracle.com [141.146.116.12]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x8GHJsEq014272; Mon, 16 Sep 2019 17:19:54 GMT Received: from ca-mkp.ca.oracle.com (/10.159.214.123) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 16 Sep 2019 10:19:53 -0700 To: Christoph Hellwig Cc: "Martin K. Petersen" , Max Gurtovoy , axboe@kernel.dk, keith.busch@intel.com, sagi@grimberg.me, israelr@mellanox.com, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, shlomin@mellanox.com Subject: Re: [PATCH v4 1/3] block: centralize PI remapping logic to the block layer From: "Martin K. Petersen" Organization: Oracle Corporation References: <1567956405-5585-1-git-send-email-maxg@mellanox.com> <61ab22ba-6f2d-3dbd-3991-693426db1133@mellanox.com> <20190916080328.GB25898@lst.de> Date: Mon, 16 Sep 2019 13:19:51 -0400 In-Reply-To: <20190916080328.GB25898@lst.de> (Christoph Hellwig's message of "Mon, 16 Sep 2019 10:03:28 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1.92 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9382 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=795 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909160171 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9382 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=870 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909160172 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Christoph, > Do we actually have Linux users of Type 3 at all? I think for NVMe > we could just trivially disable Linux support, and I suspect for SCSI > as well, but I'll have to defer to you on that. There were several companies looking into building Linux things using Type 3 SCSI devices. No idea whether this happened. I definitely still get lots of mail from people using Type 2. Something which also really shouldn't exist outside of a disk array. For NVMe, I assume nobody has tried Type 3 given the discrepancy between how SCSI works and how the NVMe spec is currently written. In any case. Since Type 3 is a pretty trivial subset of Type 1, I don't see much benefit in actively removing it. One could argue we could reduce the plumbing by removing a level of indirection. However, we'll need the infrastructure to support the impending Type 4 as well. So my preference is to just leave things as-is for now. -- Martin K. Petersen Oracle Linux Engineering