Suspend writes in RAID1 if within range

If there is a resync going on, all nodes must suspend writes to the
range. This is recorded in the suspend_info/suspend_list.

If there is an I/O within the ranges of any of the suspend_info,
should_suspend will return 1.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h
index 054f9ea..0378540 100644
--- a/drivers/md/md-cluster.h
+++ b/drivers/md/md-cluster.h
@@ -17,6 +17,7 @@
 	int (*metadata_update_start)(struct mddev *mddev);
 	int (*metadata_update_finish)(struct mddev *mddev);
 	int (*metadata_update_cancel)(struct mddev *mddev);
+	int (*area_resyncing)(struct mddev *mddev, sector_t lo, sector_t hi);
 };
 
 #endif /* _MD_CLUSTER_H */