From e6b3bb78962e65c4ad125598755cfbf2a8779e86 Mon Sep 17 00:00:00 2001 From: Carlos Maiolino Date: Wed, 18 May 2016 11:11:27 +1000 Subject: xfs: add "fail at unmount" error handling configuration If we take "retry forever" literally on metadata IO errors, we can hang at unmount, once it retries those writes forever. This is the default behavior, unfortunately. Add an error configuration option for this behavior and default it to "fail" so that an unmount will trigger actuall errors, a shutdown and allow the unmount to succeed. It will be noisy, though, as it will log the errors and shutdown that occurs. To fix this, we need to mark the filesystem as being in the process of unmounting. Do this with a mount flag that is added at the appropriate time (i.e. before the blocking AIL sync). We also need to add this flag if mount fails after the initial phase of log recovery has been run. Signed-off-by: Dave Chinner Signed-off-by: Carlos Maiolino Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- fs/xfs/xfs_mount.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'fs/xfs/xfs_mount.c') diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 677c3e0da472..7c05a22c1a73 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -681,6 +681,9 @@ xfs_mountfs( xfs_set_maxicount(mp); + /* enable fail_at_unmount as default */ + mp->m_fail_unmount = 1; + error = xfs_sysfs_init(&mp->m_kobj, &xfs_mp_ktype, NULL, mp->m_fsname); if (error) goto out; @@ -962,6 +965,7 @@ xfs_mountfs( cancel_delayed_work_sync(&mp->m_reclaim_work); xfs_reclaim_inodes(mp, SYNC_WAIT); out_log_dealloc: + mp->m_flags |= XFS_MOUNT_UNMOUNTING; xfs_log_mount_cancel(mp); out_fail_wait: if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) @@ -1012,6 +1016,14 @@ xfs_unmountfs( */ xfs_log_force(mp, XFS_LOG_SYNC); + /* + * We now need to tell the world we are unmounting. This will allow + * us to detect that the filesystem is going away and we should error + * out anything that we have been retrying in the background. This will + * prevent neverending retries in AIL pushing from hanging the unmount. + */ + mp->m_flags |= XFS_MOUNT_UNMOUNTING; + /* * Flush all pending changes from the AIL. */ -- cgit v1.2.3