From patchwork Fri Jul 20 00:16:56 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Verma, Vishal L" X-Patchwork-Id: 10535827 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D1ABF603B5 for ; Fri, 20 Jul 2018 00:17:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BBC7728A02 for ; Fri, 20 Jul 2018 00:17:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AF9CA29961; Fri, 20 Jul 2018 00:17:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 62A3F28A02 for ; Fri, 20 Jul 2018 00:17:03 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id EBB1D2098EA9B; Thu, 19 Jul 2018 17:17:02 -0700 (PDT) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=192.55.52.120; helo=mga04.intel.com; envelope-from=vishal.l.verma@intel.com; receiver=linux-nvdimm@lists.01.org Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 9EA5A2098EA8C for ; Thu, 19 Jul 2018 17:17:01 -0700 (PDT) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Jul 2018 17:17:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,376,1526367600"; d="scan'208";a="217463866" Received: from vverma7-desk1.lm.intel.com ([10.232.112.133]) by orsmga004.jf.intel.com with ESMTP; 19 Jul 2018 17:17:00 -0700 From: Vishal Verma To: Subject: [ndctl PATCH] Documentation, create-namespace: clarify fsdax wording Date: Thu, 19 Jul 2018 18:16:56 -0600 Message-Id: <20180720001656.16990-1-vishal.l.verma@intel.com> X-Mailer: git-send-email 2.14.4 X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP Reword the description of the fsdax mode in the create-namespace documentation to better distinguish when DAX can be used vs. how the raw block device will use the page cache. Link: https://github.com/pmem/issues/issues/915 Cc: Dan Williams Signed-off-by: Vishal Verma Reviewed-by: Ross Zwisler --- Documentation/ndctl/ndctl-create-namespace.txt | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/Documentation/ndctl/ndctl-create-namespace.txt b/Documentation/ndctl/ndctl-create-namespace.txt index 4b8b0d1..343733d 100644 --- a/Documentation/ndctl/ndctl-create-namespace.txt +++ b/Documentation/ndctl/ndctl-create-namespace.txt @@ -68,10 +68,11 @@ OPTIONS comes at the cost of allocating per-page metadata. The capacity can be allocated from "System RAM", or from a reserved portion of "Persistent Memory" (see the --map= - option). Note that a filesystem is required for dax - operation, the resulting raw block device (/dev/pmemX) will - use the page cache. See "devdax" mode for raw device access - that supports dax. + option). NOTE: A filesystem that supports DAX is required + for dax operation. If the raw block device (/dev/pmemX) is + used directly without a filesystem, it will use the page + cache. See "devdax" mode for raw device access that supports + dax. - "devdax": The device-dax character device interface is a statically allocated / raw access analogue of filesystem-dax