From patchwork Fri Aug 27 07:50:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 12461443 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 F2194C19F37 for ; Fri, 27 Aug 2021 07:50:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE0E46023E for ; Fri, 27 Aug 2021 07:50:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244537AbhH0Hvn (ORCPT ); Fri, 27 Aug 2021 03:51:43 -0400 Received: from esa3.hgst.iphmx.com ([216.71.153.141]:42485 "EHLO esa3.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244542AbhH0Hvk (ORCPT ); Fri, 27 Aug 2021 03:51:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1630050651; x=1661586651; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=5rn+rIGZyCcnRoiq+blOYH9u92Uq0PoXUIKA2y3DWbE=; b=dD9VhdgPAXmzb+SRyCeEILA0TwOJFiXfSiSUiCp2F1B4whXb4tiXGUdJ nbBFKZG2NOPkT3gD+5/qWim8quXizb+t/EWc9ypApWkFsW3/qOcRHRLqk 1XhG/J3lHrlch8rsw1bjeIiPhBgdgLEcyI9EqiSDv8mkE+HGUrIKoQx/o zo1q1td2X42vj2Slgki0iYZmy/9tFyN3QLCTMHr72BqLIMSmDpgZtU4Qa hSESpSaaYaoFdcKsjOYxmSUj0+EriQT8pHqyLd+rpVMedEi7wNec7LZkc wXrF0XX3pKlOLIYOKsfcO5ursu0Wfxgh+xNjWiUDugloOt3FRTcE+zFI7 A==; X-IronPort-AV: E=Sophos;i="5.84,356,1620662400"; d="scan'208";a="183342793" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 27 Aug 2021 15:50:51 +0800 IronPort-SDR: 6yeqTUueLWK8fTGAFvgqxfdS1dcCCEmACs7eMGXK8AXuHUj7lJJDZFLxZbDqqyq6LNp44ZGu/k qCKomzk7u6K1zg2tQpW1Xh3Gv6vxT3rYnQhVfmheVCNTct/rNe4C4wKm7+EgP/Kwy1X8eGZlyy nsEzGZ0VFv6WbkAlYt37v24g5t3py4qe/5KYRM37N3qpo4LOGl7BVp8/KuD/4N1lgsTMmgdYgg wPxLAx/JIEOfutHVnXSEAP4WU2qWYzHtM39hPI6rMxEJBsEbP8eZLRDf/wv3kEPYgr5BRwY1Ug gQsZfLjeFwhMo4s30YDN8Y4Y Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Aug 2021 00:26:03 -0700 IronPort-SDR: rH8ZzW6Fw9EBpZDViIu6Bd2MSQ7YYr1TH6CKslcS3ECk7+QVYLYPUOQusQ0rkc3YJBQ7uDdXsU hzZ4e0RZ0usr3sCg4hY+O5Dg1e7DuoPmLN3lq3c+P0+O9c8JRRfDJSq8fjQx67bTWKOeqv2Nj2 IF/+7shlqiB8ZSmFPEL/5m8N72x9O6ldrd8GI6hrDWRcYsILdjIT4flDv0saNtouKgBs4UIiyp YRCEOiYq3+QjVC680iQcsV+6jdboqiQAluzNc/kthECs+BJNN5gBNshs8G+OdNc77iBX5vw4my MaE= WDCIronportException: Internal Received: from washi.fujisawa.hgst.com ([10.149.53.254]) by uls-op-cesaip02.wdc.com with ESMTP; 27 Aug 2021 00:50:51 -0700 From: Damien Le Moal To: Jens Axboe , linux-block@vger.kernel.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org Subject: [PATCH v6 4/5] doc: document sysfs queue/independent_access_ranges attributes Date: Fri, 27 Aug 2021 16:50:43 +0900 Message-Id: <20210827075045.642269-5-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210827075045.642269-1-damien.lemoal@wdc.com> References: <20210827075045.642269-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Update the file Documentation/block/queue-sysfs.rst to add a description of a device queue sysfs entries related to independent access ranges (e.g. concurrent positioning ranges for multi-actuator hard-disks). Signed-off-by: Damien Le Moal --- Documentation/block/queue-sysfs.rst | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst index 4dc7f0d499a8..17eef55434e7 100644 --- a/Documentation/block/queue-sysfs.rst +++ b/Documentation/block/queue-sysfs.rst @@ -286,4 +286,32 @@ sequential zones of zoned block devices (devices with a zoned attributed that reports "host-managed" or "host-aware"). This value is always 0 for regular block devices. +independent_access_ranges (RO) +------------------------------ + +The presence of this sub-directory of the /sys/block/xxx/queue/ directory +indicates that the device is capable of executing requests targeting +different sector ranges in parallel. For instance, single LUN multi-actuator +hard-disks will likely have an independent_access_ranges directory if the +device correctly advertizes the sector ranges of its actuators. + +The independent_access_ranges directory contains one directory per access +range, with each range described using the sector (RO) attribute file to +indicate the first sector of the range and the nr_sectors (RO) attribute file +to indicate the total number of sector in the range starting from the first +sector of the range. For example, a dual-actuator hard disk will have the +following independent_access_ranges entries.:: + + $ tree /sys/block//queue/independent_access_ranges/ + /sys/block//queue/independent_access_ranges/ + |-- 0 + | |-- nr_sectors + | `-- sector + `-- 1 + |-- nr_sectors + `-- sector + +The sector and nr_sectors attributes use 512B sector unit, regardless of +the actual block size of the device. + Jens Axboe , February 2009