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>

drivers/md/md.c

@@ -68,6 +68,7 @@ static LIST_HEAD(pers_list);
 static DEFINE_SPINLOCK(pers_lock);
 
 struct md_cluster_operations *md_cluster_ops;
+EXPORT_SYMBOL(md_cluster_ops);
 struct module *md_cluster_mod;
 EXPORT_SYMBOL(md_cluster_mod);