| Message ID | 9a573fb1-0d4c-e393-b0b7-a0688b3849e5@sandeen.net (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Thu, Mar 09, 2017 at 02:15:01PM -0600, Eric Sandeen wrote: > 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> > > diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c > index b1469f0..62176b8 100644 > --- a/fs/xfs/xfs_log.c > +++ b/fs/xfs/xfs_log.c > @@ -801,11 +801,14 @@ > int error; > > /* > - * Don't write out unmount record on read-only mounts. > + * Don't write out unmount record on norecovery mounts or ro devices. > * Or, if we are doing a forced umount (typically because of IO errors). > */ > - if (mp->m_flags & XFS_MOUNT_RDONLY) > + if (mp->m_flags & XFS_MOUNT_NORECOVERY || > + xfs_readonly_buftarg(log->l_mp->m_logdev_targp)) { > + ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); > return 0; > + } > > error = _xfs_log_force(mp, XFS_LOG_SYNC, NULL); > ASSERT(error || !(XLOG_FORCED_SHUTDOWN(log))); > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index b1469f0..62176b8 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -801,11 +801,14 @@ int error; /* - * Don't write out unmount record on read-only mounts. + * Don't write out unmount record on norecovery mounts or ro devices. * Or, if we are doing a forced umount (typically because of IO errors). */ - if (mp->m_flags & XFS_MOUNT_RDONLY) + if (mp->m_flags & XFS_MOUNT_NORECOVERY || + xfs_readonly_buftarg(log->l_mp->m_logdev_targp)) { + ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); return 0; + } error = _xfs_log_force(mp, XFS_LOG_SYNC, NULL); ASSERT(error || !(XLOG_FORCED_SHUTDOWN(log)));
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> --- -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html