From patchwork Mon Jan 6 01:58:25 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 3435191 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 619AD9F399 for ; Mon, 6 Jan 2014 01:57:53 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 870E620163 for ; Mon, 6 Jan 2014 01:57:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 84B722016C for ; Mon, 6 Jan 2014 01:57:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752142AbaAFB5t (ORCPT ); Sun, 5 Jan 2014 20:57:49 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:23518 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751956AbaAFB5p (ORCPT ); Sun, 5 Jan 2014 20:57:45 -0500 X-IronPort-AV: E=Sophos;i="4.95,609,1384272000"; d="scan'208";a="9375728" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 06 Jan 2014 09:54:07 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id s061vfHN002425 for ; Mon, 6 Jan 2014 09:57:43 +0800 Received: from adam-work.lan ([10.167.226.24]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2014010609564375-834989 ; Mon, 6 Jan 2014 09:56:43 +0800 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH v3 1/9] btrfs: Add "barrier" option to support "-o remount, barrier" Date: Mon, 6 Jan 2014 09:58:25 +0800 Message-Id: <1388973513-11240-2-git-send-email-quwenruo@cn.fujitsu.com> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1388973513-11240-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1388973513-11240-1-git-send-email-quwenruo@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2014/01/06 09:56:43, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2014/01/06 09:56:45, Serialize complete at 2014/01/06 09:56:45 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-7.0 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Btrfs can be remounted without barrier, but there is no "barrier" option so nobody can remount btrfs back with barrier on. Only umount and mount again can re-enable barrier.(Quite awkward) Also the mount options in the document is also changed slightly for the further pairing options changes. Reported-by: Daniel Blueman Signed-off-by: Qu Wenruo Signed-off-by: Mike Fleetwood Reviewed-by: David Sterba --- Changelog: v1: Add barrier option v2: Document style change v3: Small description change --- Documentation/filesystems/btrfs.txt | 13 +++++++------ fs/btrfs/super.c | 8 +++++++- 2 files changed, 14 insertions(+), 7 deletions(-) diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt index 5dd282d..ce487a2 100644 --- a/Documentation/filesystems/btrfs.txt +++ b/Documentation/filesystems/btrfs.txt @@ -38,7 +38,7 @@ Mount Options ============= When mounting a btrfs filesystem, the following option are accepted. -Unless otherwise specified, all options default to off. +Options with (*) are default options and will not show in the mount options. alloc_start= Debugging option to force all block allocations above a certain @@ -138,12 +138,13 @@ Unless otherwise specified, all options default to off. Disable support for Posix Access Control Lists (ACLs). See the acl(5) manual page for more information about ACLs. + barrier(*) nobarrier - Disables the use of block layer write barriers. Write barriers ensure - that certain IOs make it through the device cache and are on persistent - storage. If used on a device with a volatile (non-battery-backed) - write-back cache, this option will lead to filesystem corruption on a - system crash or power loss. + Enable/disable the use of block layer write barriers. Write barriers + ensure that certain IOs make it through the device cache and are on + persistent storage. If disabled on a device with a volatile + (non-battery-backed) write-back cache, nobarrier option will lead to + filesystem corruption on a system crash or power loss. nodatacow Disable data copy-on-write for newly created files. Implies nodatasum, diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index e9c13fb..fe9d8a6 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -323,7 +323,7 @@ enum { Opt_no_space_cache, Opt_recovery, Opt_skip_balance, Opt_check_integrity, Opt_check_integrity_including_extent_data, Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, - Opt_commit_interval, + Opt_commit_interval, Opt_barrier, Opt_err, }; @@ -335,6 +335,7 @@ static match_table_t tokens = { {Opt_nodatasum, "nodatasum"}, {Opt_nodatacow, "nodatacow"}, {Opt_nobarrier, "nobarrier"}, + {Opt_barrier, "barrier"}, {Opt_max_inline, "max_inline=%s"}, {Opt_alloc_start, "alloc_start=%s"}, {Opt_thread_pool, "thread_pool=%d"}, @@ -494,6 +495,11 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) btrfs_clear_opt(info->mount_opt, SSD); btrfs_clear_opt(info->mount_opt, SSD_SPREAD); break; + case Opt_barrier: + if (btrfs_test_opt(root, NOBARRIER)) + btrfs_info(root->fs_info, "turning on barriers"); + btrfs_clear_opt(info->mount_opt, NOBARRIER); + break; case Opt_nobarrier: btrfs_info(root->fs_info, "turning off barriers"); btrfs_set_opt(info->mount_opt, NOBARRIER);