From patchwork Wed Sep 9 10:26:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Thumshirn X-Patchwork-Id: 11765305 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E2B3D618 for ; Wed, 9 Sep 2020 10:26:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C57E121D82 for ; Wed, 9 Sep 2020 10:26:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="H1EpbGtw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727900AbgIIK0q (ORCPT ); Wed, 9 Sep 2020 06:26:46 -0400 Received: from esa1.hgst.iphmx.com ([68.232.141.245]:43811 "EHLO esa1.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725877AbgIIK0g (ORCPT ); Wed, 9 Sep 2020 06:26:36 -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=1599647196; x=1631183196; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Mw92ho8PPfqLP3dj3WwR/jhErPBWuGbZ4I7LMFxaQ/4=; b=H1EpbGtwAxltre6MqtuTjyMo4bNaInounkZlzi0a3sqLk5SjyBktztEt tMC2xRZ2jY2C3TyUThe5JQKo2aBo9fRvo6WVhcFnoohR2VnD6C1F3sQgY TcDepDwGCILRNcMLlQXxE78yXdrBglbn8ZlKciSuN1cgl2CJ0vFgtxcFh r+U/XgocdMyukoxnMbxsxk7ldODb5AgGms42K87TyphQ6Lg7ToVfZi/rh I1/+FXGg/CUzCPsEB5oMAOC1dmszvdncNX+1Pv7fOlPDyXSugkD1STPhH kmDzsCzfIHhmMeczOiqjz5IUANDSEo7bQ+cMzXBM+QiOKV+TElMNM5LJY w==; IronPort-SDR: VpYXexOUQxLqWuUKC2thFtYk8gJwoEUC2qqI4bCaHepufOGll4+y9s56fvcHP9Vwuz5/R6Uk70 lhPCjCDTQvwvlo9nYwmERw32NCXABCUtOwKDhk8faYYQLJGE+Ozv4RT9oDFZO43XPRvX6f8prg 0gA1JYKUdauBpmJs4F1uWqgbsKZOswNyHWYIJVyicNAv5muAm+8sIMlPecM4KoyWWq2uA3Ez9T 6mTdmVnHY7LtVssSqfEhwnvpnOMCWaJlmWnZmyGl4rQsncsKdcItjCGH9qPp1U+/czKzaFKs44 Gfo= X-IronPort-AV: E=Sophos;i="5.76,409,1592841600"; d="scan'208";a="256500009" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 09 Sep 2020 18:26:34 +0800 IronPort-SDR: XADWj5MnBUxFOuBpzmcbks74P7x0vHm0wrwMHPOwxew39PPZmFUS3vZNZp4M9Qt/YjNiMVRhRJ eDi+fJuaTeaw== 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; 09 Sep 2020 03:13:52 -0700 IronPort-SDR: XQ6lMlLohu3wAWFFDiLIYrbbPghflCgBvhj0YTkKKCmtUlyx541YqmsS78Rp0iVO7CnpE1+Am4 agsahIA23Ddw== WDCIronportException: Internal Received: from unknown (HELO redsun60.ssa.fujisawa.hgst.com) ([10.149.66.36]) by uls-op-cesaip02.wdc.com with ESMTP; 09 Sep 2020 03:26:33 -0700 From: Johannes Thumshirn To: Damien Le Moal Cc: linux-fsdevel@vger.kernel.org, Johannes Thumshirn Subject: [PATCH v2 3/3] zonefs: document the explicit-open mount option Date: Wed, 9 Sep 2020 19:26:14 +0900 Message-Id: <20200909102614.40585-4-johannes.thumshirn@wdc.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200909102614.40585-1-johannes.thumshirn@wdc.com> References: <20200909102614.40585-1-johannes.thumshirn@wdc.com> MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Document the newly introduced explicit-open mount option. Signed-off-by: Johannes Thumshirn Reviewed-by: Damien Le Moal --- Changes to v1: - Address Randy's comments --- Documentation/filesystems/zonefs.rst | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/Documentation/filesystems/zonefs.rst b/Documentation/filesystems/zonefs.rst index 6c18bc8ce332..6b213fe9a33e 100644 --- a/Documentation/filesystems/zonefs.rst +++ b/Documentation/filesystems/zonefs.rst @@ -326,6 +326,21 @@ discover the amount of data that has been written to the zone. In the case of a read-only zone discovered at run-time, as indicated in the previous section. The size of the zone file is left unchanged from its last updated value. +A zoned block device (e.g. an NVMe Zoned Namespace device) may have limits on +the number of zones that can be active, that is, zones that are in the +implicit open, explicit open or closed conditions. This potential limitation +translates into a risk for applications to see write IO errors due to this +limit being exceeded if the zone of a file is not already active when a write +request is issued by the user. + +To avoid these potential errors, the "explicit-open" mount option forces zones +to be made active using an open zone command when a file is opened for writing +for the first time. If the zone open command succeeds, the application is then +guaranteed that write requests can be processed. Conversely, the +"explicit-open" mount option will result in a zone close command being issued +to the device on the last close() of a zone file if the zone is not full nor +empty. + Zonefs User Space Tools =======================