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=-3.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,UNPARSEABLE_RELAY 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 8F33AC43387 for ; Fri, 4 Jan 2019 06:12:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AB5121871 for ; Fri, 4 Jan 2019 06:12:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="3rJ+zKvp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727303AbfADGMH (ORCPT ); Fri, 4 Jan 2019 01:12:07 -0500 Received: from aserp2130.oracle.com ([141.146.126.79]:60984 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726679AbfADGMD (ORCPT ); Fri, 4 Jan 2019 01:12:03 -0500 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id x0469DNf120714; Fri, 4 Jan 2019 06:11:54 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-2018-07-02; bh=8zIchHV4RQyk+6MQv0cOkh7RiQWpg8cazpdY8JNeqoI=; b=3rJ+zKvprXsprmcPrlvEAYLSL3x6qTppLfGHicSBD7jjMzJwhO8GzEYyHehypEq3HMiY biq3FfbJ+cabkEb33nvbq8uroZjES4jo3JAwL/5zgcmMalO/KxEwPuQCXXb0Z4HCZHA+ 7Nw+nuNcwRvIb+LHm9Xua2OUFl4o2m/R5uA+yaPtP7IPoVD3iPSYu1qSEk+AVSwbh8tF U42K/dfA+IXXWljj5ntKmcbydZalNLHY0zbfQ7WRZPIVCEbUbNp/IjUPg65zFnr7IXtH RRz4btqpq5pdLSQcq9SCJT5oQ+CT8iJ7apL/jL0Kdd4EP9K5EUdw858/M/XWSzEIr4zg NA== Received: from aserv0022.oracle.com (aserv0022.oracle.com [141.146.126.234]) by aserp2130.oracle.com with ESMTP id 2pnxeeapu2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 04 Jan 2019 06:11:54 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserv0022.oracle.com (8.14.4/8.14.4) with ESMTP id x046Brwi028394 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 4 Jan 2019 06:11:53 GMT Received: from abhmp0004.oracle.com (abhmp0004.oracle.com [141.146.116.10]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x046BqK9022808; Fri, 4 Jan 2019 06:11:52 GMT Received: from ca-mkp.ca.oracle.com (/10.159.214.123) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 03 Jan 2019 22:11:51 -0800 To: Randall Huang Cc: "Martin K. Petersen" , jejb@linux.vnet.ibm.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, huangrandall@google.com Subject: Re: [PATCH] scsi: associate bio write hint with WRITE CDB From: "Martin K. Petersen" Organization: Oracle Corporation References: <20181226041504.66283-1-huangrandall@google.com> <20190103075133.GA5141@infradead.org> <20190103094755.GA96532@google.com> <6152b478ea77dacf57eef6f758ba795f756cd3da.camel@redhat.com> <20190104052251.GA205256@google.com> Date: Fri, 04 Jan 2019 01:11:49 -0500 In-Reply-To: <20190104052251.GA205256@google.com> (Randall Huang's message of "Fri, 4 Jan 2019 13:22:51 +0800") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9125 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=907 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1901040054 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Randall, > I am working on Android phone. > The idea is to enable write hint for Turbo write UFS feature. Turbo > write feature in UFS 3.x is under discussion in JEDEC JC-64. This > patch is the under-lying framework for supporting this feature. OK, but we can't blindly go setting GROUP NUMBER to a non-zero value. That'll break a massive amount of devices which will fail READ/WRITE commands with INVALID FIELD IN CDB. So aside from requiring the device to report GROUP_SUP=1, we'll need some sort of indication that this device supports the UFS Turbo Write feature. If you are engaged with JEDEC on this, please tell them we'll need a VPD page, a mode page, or something similar to use as trigger to entertain enabling this feature. -- Martin K. Petersen Oracle Linux Engineering