From patchwork Thu Aug 12 02:26:25 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: 12432311 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,URIBL_BLOCKED,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 79E15C432BE for ; Thu, 12 Aug 2021 02:26:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EC066109E for ; Thu, 12 Aug 2021 02:26:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233652AbhHLC1T (ORCPT ); Wed, 11 Aug 2021 22:27:19 -0400 Received: from esa2.hgst.iphmx.com ([68.232.143.124]:55307 "EHLO esa2.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233677AbhHLC1Q (ORCPT ); Wed, 11 Aug 2021 22:27:16 -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=1628735212; x=1660271212; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=YlAMtc1NFjSacQjRaTROX9F+tPKC3ulFDw9e3bnV9hc=; b=S+J4QxlDP4M4U5mKyYZbkeW4TS4q6Lnl4lR6fVxr4xtSLrcY+iSQyC9k zdPqhpyprPthwr6qk6m4C/RhAyK0+qIA6dpjUyqu235whH5rctuafM0nC 46IvLb6xssS8h4iAhFORwbdjF+8nvjxH+CLvydYNbxYB52NiYNhUGLFgu nki0VJWQB5Casak1VMgLKJYJp4QAOYNcDyBvUnmb9AzE2lnTnnr2WPPKy NYA/KLL1EaZYPmKdZ6sZuY9Rc3UKgDYACrwVRPHG0P6zgQjdPxPxsXq/W 1uAlWTL2qIxxFpEn0VR8ivtp7TAWOFGshq2urYX5N7iqvYmmQAEZoFMSy w==; X-IronPort-AV: E=Sophos;i="5.84,314,1620662400"; d="scan'208";a="280823447" Received: from h199-255-45-14.hgst.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 12 Aug 2021 10:26:51 +0800 IronPort-SDR: F8L9J5rhEmP9+/VTbMjVYNjCg9I2NjPb5Tg/urvNCmx/AjTMUugVPOV6bh548eKN7oz49ISShL Q6wwr9wtHAqKUwwBDzs5TciNHFRsLRY0TqTeObGNQUBYvMXktFSTyOqSjqeRgDK0mp/U4jOLE4 3eQ5a1eugKfFomjl0QGb146dhgrmkOV+Voi1XAGR/SgI+EfXvSOk7Cpk9GBlEFKTLeM6CLQPkr 4fSjiy26mG0EvBRiLufoVUpOO4O+iFx+4me4WVOrSUyAHmMDGWjGA15sEcOzmVowjouyqkZSN3 4qAmjpyyamANK0SQxU090DoN Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Aug 2021 19:04:11 -0700 IronPort-SDR: lJREHWqVL3eXXswXTUw02WIfvDfJPa6EGfnf7NlUwgKpkCTy0okz87liIltWTZ+dVcLVVS8pYv zsVOPP7FC4ycP7cbwIoBFAZ3S/3sP7gElw+yga632FADis+SA/emfUgk0azvc2bi437n7fbYFh ke9w5F3hd5vyNhtSOvQBx5snpuNbf+gFgMflPjfCKshFuR6gLEzmgalyFfK/FHrj94chHCqnI+ c2aMO1POEOeLaEttTHp0nCmupckAHAWZkgQG/WGPLiW8JSiBaL92HIkskP7BW7HcWIEXcDmPiA 5io= WDCIronportException: Internal Received: from washi.fujisawa.hgst.com ([10.149.53.254]) by uls-op-cesaip02.wdc.com with ESMTP; 11 Aug 2021 19:26:51 -0700 From: Damien Le Moal To: Jens Axboe , linux-block@vger.kernel.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org Subject: [PATCH v4 4/5] doc: document sysfs queue/cranges attributes Date: Thu, 12 Aug 2021 11:26:25 +0900 Message-Id: <20210812022626.694329-5-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210812022626.694329-1-damien.lemoal@wdc.com> References: <20210812022626.694329-1-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 concurrent sector ranges (e.g. concurrent positioning ranges for multi-actuator hard-disks). While at it, also fix a typo in this file introduction paragraph. Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig --- 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..757609bbb1e2 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. +cranges (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 a cranges directory if the device correctly +advertizes the sector ranges of its actuators. + +The cranges directory contains one directory per concurrent 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. +For example, a dual-actuator hard disk will have the following cranges +entries.:: + + $ tree /sys/block//queue/cranges/ + /sys/block//queue/cranges/ + |-- 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