dlm: increment ls_count for dlm_scand

Increment the ls_count value while dlm_scand is processing a
lockspace so that release_lockspace()/remove_lockspace() will
wait for dlm_scand to finish.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

fs/dlm/lockspace.c

@@ -255,6 +255,7 @@ static struct dlm_ls *find_ls_to_scan(void)
 	list_for_each_entry(ls, &lslist, ls_list) {
 		if (time_after_eq(jiffies, ls->ls_scan_time +
 					    dlm_config.ci_scan_secs * HZ)) {
+			atomic_inc(&ls->ls_count);
 			spin_unlock_bh(&lslist_lock);
 			return ls;
 		}
@@ -277,6 +278,8 @@ static int dlm_scand(void *data)
 			} else {
 				ls->ls_scan_time += HZ;
 			}
+
+			dlm_put_lockspace(ls);
 			continue;
 		}
 		schedule_timeout_interruptible(dlm_config.ci_scan_secs * HZ);