From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from szxga05-in.huawei.com ([45.249.212.191]:5083 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751086AbdHaOMT (ORCPT ); Thu, 31 Aug 2017 10:12:19 -0400 From: Hou Tao Subject: [PATCH v2] xfs: add online uevent for mount operation Date: Thu, 31 Aug 2017 22:17:10 +0800 Message-ID: <1504189030-18608-1-git-send-email-houtao1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: linux-xfs@vger.kernel.org Cc: darrick.wong@oracle.com, david@fromorbit.com It will be useful if there is a corresponding online uevent after a XFS filesystem has been mounted. A typical usage of the uevent is setting the error configuration for a specific XFS filesystem or all XFS filesystems by using udevd. The following is an example of udevd rule which will shutdown any XFS filesystem after the filesystem gets any IO error: ACTION=="online", SUBSYSTEM=="xfs", DEVPATH=="/fs/xfs/*", \ RUN+="/bin/sh -c 'echo 0 > /sys%p/error/metadata/default/max_retries; \ echo 0 > /sys%p/error/metadata/EIO/max_retries; \ echo 0 > /sys%p/error/metadata/ENOSPC/max_retries; \ echo 0 > /sys%p/error/metadata/ENODEV/max_retries'" You also could apply an udevd rule to a specific XFS filesystem by UUID filtering: ACTION=="online", SUBSYSTEM=="xfs", \ ENV{UUID}=="8f789c27-391f-4bd7-b17d-9bcf2443dc9c", \ RUN+="/bin/sh -c 'echo 5 > /sys%p/error/metadata/EIO/max_retries'" Suggested-by: Dave Chinner Signed-off-by: Hou Tao --- v2: * add UUID property for mount uevent * add an udev example for UUID filtering v1: * http://www.spinics.net/lists/linux-xfs/msg09484.html --- fs/xfs/xfs_super.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 3a3812b4..6f8351c 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -70,6 +70,11 @@ static struct kset *xfs_kset; /* top-level xfs sysfs dir */ static struct xfs_kobj xfs_dbg_kobj; /* global debug sysfs attrs */ #endif +enum { + XFS_UEVENT_ENV_CNT = 2, + XFS_UEVENT_UUID_LEN = UUID_STRING_LEN + 6, +}; + /* * Table driven mount option parser. */ @@ -1530,6 +1535,28 @@ xfs_destroy_percpu_counters( percpu_counter_destroy(&mp->m_fdblocks); } +static void +xfs_fs_uevent( + struct xfs_mount *mp, + enum kobject_action action) +{ + int err; + char *envp[XFS_UEVENT_ENV_CNT]; + int i = 0; + + if (!uuid_is_null(&mp->m_super->s_uuid)) { + char uuid[XFS_UEVENT_UUID_LEN]; + + snprintf(uuid, sizeof(uuid), "UUID=%pUb", &mp->m_super->s_uuid); + envp[i++] = uuid; + } + envp[i] = NULL; + err = kobject_uevent_env(&mp->m_kobj.kobject, action, envp); + if (err) + xfs_notice(mp, "Sending XFS uevent %d got error %d", + action, err); +} + STATIC int xfs_fs_fill_super( struct super_block *sb, @@ -1667,6 +1694,8 @@ xfs_fs_fill_super( goto out_unmount; } + xfs_fs_uevent(mp, KOBJ_ONLINE); + return 0; out_filestream_unmount: -- 2.5.0