From patchwork Thu Sep 10 07:59:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Thumshirn X-Patchwork-Id: 11766981 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 B0AB2618 for ; Thu, 10 Sep 2020 08:00:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 87CED2054F for ; Thu, 10 Sep 2020 08:00:30 +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="lTm9Em/z" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727820AbgIJIA2 (ORCPT ); Thu, 10 Sep 2020 04:00:28 -0400 Received: from esa6.hgst.iphmx.com ([216.71.154.45]:52840 "EHLO esa6.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726893AbgIJIAN (ORCPT ); Thu, 10 Sep 2020 04:00:13 -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=1599724814; x=1631260814; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=sMgkTYfIVhjzdVujgdBcvqxrVYyGCgcXIKPhIxj2SRw=; b=lTm9Em/zkakI0ZPbY2QxL+ZFUkSV0v0tGa3mgtM+yemT/nL0bGMpbiZP ropu61bnBfcW23fVpzLqI7vCoxO1mhYLQA/OJgz5MJ9+nO1n2J/2H59rD InlUu2sGSOBQhkToT0faKEtQxgJC9QX3w+K2S6xAOPyr2VHOz6tOLq0SY y4Vn88BAG1bvLC5/uGy5A6slHaFxbReMP8hF3n1WtNQdipwr8FDEl6fiU W2gddBZU9k+ojMi7aNswQjTNgqu6k1/7iVUlNAai9TXkqeN+FWE6mkk44 vSodwQasa/jYnB53LFIqRuKfDffJuQmw+CvHN1kiptXj6VwC9v6LxTA01 Q==; IronPort-SDR: HyEEx0XnKXgPPL2PHjVT/FnUPnXWRQV5bpTkvRAPGlKHn5Gi9JFCo6ptGQc72XPVPOU0PcnAnl CMJd+NUEaQwqVneFV8KgITGog3IiqsfSOemy4giQu5lz1yIzMSbv7pjANtzAHPwfPVJ5eoZucT PfPwklLYMUPV0ATZQDZnLc1esGzMCg4jTDlsR0xS7dOo8P3mxAuhcXtkImBKw2NxFtTCWS9R3T fSi6AOBQXH06lWzKsHYzkGNtr4Lhg3t4X4G9iBAMUvLT3WYL5x5aac1O0IzTE80lK5JSA/SvxQ WEA= X-IronPort-AV: E=Sophos;i="5.76,412,1592841600"; d="scan'208";a="148233444" 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; 10 Sep 2020 16:00:13 +0800 IronPort-SDR: tnsv+kokqnAjehCZJ+hRj8uirtA+qfScgMQqpB/AEfzvKDhtbNJf/jklzWloB5S3eO+xZBQwkC wvZmUUoibQpg== Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Sep 2020 00:47:30 -0700 IronPort-SDR: Y0E5G24OEbuPKOjdh+sYszIrDE8g5TENzkXeypXy24HqT+1u+CmVfBomWvU5aerLRs6ktob6Kn DWDBPGMb3B+A== WDCIronportException: Internal Received: from unknown (HELO redsun60.ssa.fujisawa.hgst.com) ([10.149.66.36]) by uls-op-cesaip01.wdc.com with ESMTP; 10 Sep 2020 01:00:13 -0700 From: Johannes Thumshirn To: Damien Le Moal Cc: linux-fsdevel@vger.kernel.org, Johannes Thumshirn , Damien Le Moal Subject: [PATCH v3 3/3] zonefs: document the explicit-open mount option Date: Thu, 10 Sep 2020 16:59:57 +0900 Message-Id: <20200910075957.7307-4-johannes.thumshirn@wdc.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200910075957.7307-1-johannes.thumshirn@wdc.com> References: <20200910075957.7307-1-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 =======================