md-cluster: introduce resync_info_get interface for sanity check

Since the resync region from suspend_info means one node
is reshaping this area, so the position of reshape_progress
should be included in the area.

Reviewed-by: NeilBrown <[e-mail]>
Signed-off-by: Guoqing Jiang <[e-mail]>
Signed-off-by: Shaohua Li <[e-mail]>

drivers/md/md-cluster.c

···
 	return dlm_lock_sync_interruptible(cinfo->resync_lockres, DLM_LOCK_EX, mddev);
 }
 
+static void resync_info_get(struct mddev *mddev, sector_t *lo, sector_t *hi)
+{
+	struct md_cluster_info *cinfo = mddev->cluster_info;
+	struct suspend_info *s;
+
+	spin_lock_irq(&cinfo->suspend_lock);
+	list_for_each_entry(s, &cinfo->suspend_list, list) {
+		*lo = s->lo;
+		*hi = s->hi;
+	}
+	spin_unlock_irq(&cinfo->suspend_lock);
+}
+
 static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
 {
 	struct md_cluster_info *cinfo = mddev->cluster_info;
···
 	.resync_start = resync_start,
 	.resync_finish = resync_finish,
 	.resync_info_update = resync_info_update,
+	.resync_info_get = resync_info_get,
 	.metadata_update_start = metadata_update_start,
 	.metadata_update_finish = metadata_update_finish,
 	.metadata_update_cancel = metadata_update_cancel,

drivers/md/md-cluster.h

···
 	int (*leave)(struct mddev *mddev);
 	int (*slot_number)(struct mddev *mddev);
 	int (*resync_info_update)(struct mddev *mddev, sector_t lo, sector_t hi);
+	void (*resync_info_get)(struct mddev *mddev, sector_t *lo, sector_t *hi);
 	int (*metadata_update_start)(struct mddev *mddev);
 	int (*metadata_update_finish)(struct mddev *mddev);
 	void (*metadata_update_cancel)(struct mddev *mddev);

drivers/md/raid10.c

···
 static void raid10_update_reshape_pos(struct mddev *mddev)
 {
 	struct r10conf *conf = mddev->private;
+	sector_t lo, hi;
 
-	conf->reshape_progress = mddev->reshape_position;
+	md_cluster_ops->resync_info_get(mddev, &lo, &hi);
+	if (((mddev->reshape_position <= hi) && (mddev->reshape_position >= lo))
+	    || mddev->reshape_position == MaxSector)
+		conf->reshape_progress = mddev->reshape_position;
+	else
+		WARN_ON_ONCE(1);
 }
 
 static int handle_reshape_read_error(struct mddev *mddev,