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 3CF84C43331 for ; Wed, 13 Nov 2019 03:06:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 103A4222BD for ; Wed, 13 Nov 2019 03:06:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="GjacV2Ha" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727324AbfKMDGq (ORCPT ); Tue, 12 Nov 2019 22:06:46 -0500 Received: from aserp2120.oracle.com ([141.146.126.78]:43178 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727059AbfKMDGq (ORCPT ); Tue, 12 Nov 2019 22:06:46 -0500 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xAD34Gqa093160; Wed, 13 Nov 2019 03:06:37 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=UcUnWbUcO8uAL27ZIr6jIOj83AcLtiKVoXpB4FfilqM=; b=GjacV2HaBVKcqMHAzelHyvgg4nZSeJtWUSRjlLh4BuccCn+zJLwCmiR55CkrkkFzhgUw Wre7xSnMgnrYHanyHNJBAwXLG1Bw+5n9OQIJw5LyanyuItSKKwp+NT/2GsTitHVtf8ba 26WmkOujq2KG5JigYn0khAuFkmi28jAgFpf5nT0yJFhUaUVEWsSwu4iJJf87hPlG4/Lp /cvXGY8VV+93rOWvs/6MysEDGmGGgF2uh+H+G95M7um288/Mc3TF5fB7VrwyEeAxiBPF 07Wqt04eMxkHwr1f6Ch+TafdI0kVk0z+r6/XZTAfRf2zNyhk5Ej+zhIFPaSItoD0mjHK RA== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by aserp2120.oracle.com with ESMTP id 2w5ndq95pp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 13 Nov 2019 03:06:37 +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 xAD34QST156735; Wed, 13 Nov 2019 03:04:36 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3030.oracle.com with ESMTP id 2w7vpnfj9f-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 13 Nov 2019 03:04:36 +0000 Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id xAD33tna006318; Wed, 13 Nov 2019 03:03:56 GMT Received: from ca-mkp.ca.oracle.com (/10.159.214.123) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 12 Nov 2019 19:03:55 -0800 To: Can Guo Cc: asutoshd@codeaurora.org, nguyenb@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, "James E.J. Bottomley" , "Martin K. Petersen" , linux-kernel@vger.kernel.org (open list) Subject: Re: [PATCH v3 1/5] scsi: Adjust DBD setting in mode sense for caching mode page per LLD From: "Martin K. Petersen" Organization: Oracle Corporation References: <1572670898-750-1-git-send-email-cang@codeaurora.org> <1572670898-750-2-git-send-email-cang@codeaurora.org> Date: Tue, 12 Nov 2019 22:03:52 -0500 In-Reply-To: <1572670898-750-2-git-send-email-cang@codeaurora.org> (Can Guo's message of "Fri, 1 Nov 2019 22:01:34 -0700") 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=9439 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=850 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1910280000 definitions=main-1911130025 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9439 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=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=917 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1910280000 definitions=main-1911130025 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Can, > Host sends MODE_SENSE_10 with caching mode page, to check if the > device supports the cache feature. UFS JEDEC standards require DBD > field to be set to 1. UFS requires DBD for all MODE SENSE(10) invocations, not just for accessing the caching mode page. I think the flag name needs to reflect this. Also, I do not particularly like this being a scsi_host flag. All the other flags we have in this department are per scsi_device. My recommendation would be to add a set_dbd_for_ms flag to struct scsi_device and then do: sdev->set_dbd_for_ms = 1; in ufshcd_slave_alloc() mirroring the existing: sdev->use_10_for_ms = 1; This makes the MODE SENSE tweakery consistent. Thanks! -- Martin K. Petersen Oracle Linux Engineering