From patchwork Mon Sep 6 01:58:09 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: 12476217 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=unavailable 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 CB7B3C4332F for ; Mon, 6 Sep 2021 01:58:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B411D60EE6 for ; Mon, 6 Sep 2021 01:58:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238721AbhIFB7g (ORCPT ); Sun, 5 Sep 2021 21:59:36 -0400 Received: from esa6.hgst.iphmx.com ([216.71.154.45]:22459 "EHLO esa6.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238908AbhIFB7X (ORCPT ); Sun, 5 Sep 2021 21:59:23 -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=1630893500; x=1662429500; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=UeMxn3O3a5dQiuRdZYEQiywnhJ5mySyNi0lx2Vh5+XQ=; b=fHMXXxOKHyBwA9nHOCgCvK4aLvLjNxd40/G34Q/HtOD5kNBfyP3632DS pB7nYsaLmYNmx7ab5gzCTiIZjxv+rv1FRqYI31wGlXao39I3LeITmiKrU 1uiRIKx9MCAVAtxd06yyi4VxmtcVR2QZqGrqImrlUGU8BONuyFATwlOOX tcq0V3oLi5kj8oyfiuk8v8IMNRZNve49V0u5YHN2WgcpwOLvT5Dd8Kdg+ U3uKL9pEtA84y98OyvkYkmmBzZ7XctEF3VjP58vNeD+bMETeL7+OYczR4 JWROIpoxPXMAhXe4HL0xQRUlPkgJoyGASgo/MWxUKYIzwep7fdOkmCzEB A==; X-IronPort-AV: E=Sophos;i="5.85,271,1624291200"; d="scan'208";a="179789034" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 06 Sep 2021 09:58:20 +0800 IronPort-SDR: KUlV65eOtrQpPo4iqlt4PoFKiRgMUttlwPNg+0WbiHrfZ8Ae9VwI5ZOWSEeVK2X1lOn1mzvcNi LdxcMNmiefK4+4vdhOg7Qt44NuB84QmXW1wtSJWOLllrMr7F2GHyORaD2Yck/m8O5qlAhmTW4+ 4n95MjgP/+fDQbrpWiTL6kXhSfeC7nL+aht3++Ggd5AENwFJE0HH7kNQkl5Q9DCzuPF38z8uDg g5bcb+JRGa71B2Q9KgPrc44toKpB4JYIPQiRAn0ldR39ijSJ60b1OMq3qEF5c7FBEJOkIDJ8M8 rGsOttwEN2KeG6nt1RI1PzZH 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; 05 Sep 2021 18:33:20 -0700 IronPort-SDR: qU/VE53OEQsWG8FEzEnQVWPSz8clj1JSG9LmpWKkdBpFMIXp+zxbc1khRoCeNUB1yDVlEEuOGw vnRAlt3gPH1HfvvtAQJpNwCfU2I9yc2H8zqwS8+HJTq66Ans5jb5cIy9M1Vf8BLlhVb6Sqptyr Y3GIq5RtWunI7BKU3PRmw3jBFBfkEv5w/8QQsqgagnXCu0VT7+mw46uFFna8M/C/SCD0oV+qdg xwGhtabrKwEGsmwe7gh8yfEXjy0MTIGL8azJSUvC7P3ASPVouosjdfacHts/XJl3tH7kv3n0gZ VDY= WDCIronportException: Internal Received: from washi.fujisawa.hgst.com ([10.149.53.254]) by uls-op-cesaip02.wdc.com with ESMTP; 05 Sep 2021 18:58:19 -0700 From: Damien Le Moal To: Jens Axboe , linux-block@vger.kernel.org, linux-ide@vger.kernel.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org Subject: [PATCH v7 4/5] doc: document sysfs queue/independent_access_ranges attributes Date: Mon, 6 Sep 2021 10:58:09 +0900 Message-Id: <20210906015810.732799-5-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210906015810.732799-1-damien.lemoal@wdc.com> References: <20210906015810.732799-1-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 Reviewed-by: Hannes Reinecke --- Documentation/block/queue-sysfs.rst | 31 +++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst index 4dc7f0d499a8..b6e8983d8eda 100644 --- a/Documentation/block/queue-sysfs.rst +++ b/Documentation/block/queue-sysfs.rst @@ -286,4 +286,35 @@ 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 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 sectors 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. Independent access ranges do not +overlap and include all sectors within the device capacity. The access +ranges are numbered in increasing order of the range start sector, +that is, the sector attribute of range 0 always has the value 0. + Jens Axboe , February 2009