xfs: scrub rmap btrees

Check the reverse mapping records to make sure that the contents
make sense.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

fs/xfs/scrub/scrub.c

@@ -191,6 +191,11 @@ static const struct xfs_scrub_meta_ops meta_scrub_ops[] = {
 		.scrub	= xfs_scrub_finobt,
 		.has	= xfs_sb_version_hasfinobt,
 	},
+	{ /* rmapbt */
+		.setup	= xfs_scrub_setup_ag_rmapbt,
+		.scrub	= xfs_scrub_rmapbt,
+		.has	= xfs_sb_version_hasrmapbt,
+	},
 };
 
 /* This isn't a stable feature, warn once per day. */