xfs: sanitise sb_bad_features2 handling
We currently have to ensure that every time we update sb_features2
that we update sb_bad_features2. Now that we log and format the
superblock in it's entirety we actually don't have to care because
we can simply update the sb_bad_features2 when we format it into the
buffer. This removes the need for anything but the mount and
superblock formatting code to care about sb_bad_features2, and
hence removes the possibility that we forget to update bad_features2
when necessary in the future.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
index 63f8148..b0a5fe9 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -497,7 +497,6 @@
to->sb_fdblocks = cpu_to_be64(from->sb_fdblocks);
to->sb_frextents = cpu_to_be64(from->sb_frextents);
-
to->sb_flags = from->sb_flags;
to->sb_shared_vn = from->sb_shared_vn;
to->sb_inoalignmt = cpu_to_be32(from->sb_inoalignmt);
@@ -507,6 +506,13 @@
to->sb_logsectlog = from->sb_logsectlog;
to->sb_logsectsize = cpu_to_be16(from->sb_logsectsize);
to->sb_logsunit = cpu_to_be32(from->sb_logsunit);
+
+ /*
+ * We need to ensure that bad_features2 always matches features2.
+ * Hence we enforce that here rather than having to remember to do it
+ * everywhere else that updates features2.
+ */
+ from->sb_bad_features2 = from->sb_features2;
to->sb_features2 = cpu_to_be32(from->sb_features2);
to->sb_bad_features2 = cpu_to_be32(from->sb_bad_features2);