There are dueling comments in the xfs code about intent
for log writes when unmounting a readonly filesystem.
In xfs_mountfs, we see the intent:
/*
* Now the log is fully replayed, we can transition to full read-only
* mode for read-only mounts. This will sync all the metadata and clean
* the log so that the recovery we just performed does not have to be
* replayed again on the next mount.
*/
and it calls xfs_quiesce_attr(), but by the time we get to
xfs_log_unmount_write(), it returns early for a RDONLY mount:
* Don't write out unmount record on read-only mounts.
Because of this, sequential ro mounts of a filesystem with
a dirty log will replay the log each time, which seems odd.
Fix this by writing an unmount record even for RO mounts, as long
as norecovery wasn't specified (don't write a clean log record
if a dirty log may still be there!) and the log device is
writable.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
757a69ef6c