diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 4e913bd..0f0cd1f 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -1542,7 +1542,8 @@ heap_beginscan_internal(Relation relation, Snapshot snapshot,
  */
 void
 heap_rescan(HeapScanDesc scan,
-			ScanKey key)
+			ScanKey key,
+			bool keep_startblock)
 {
 	/*
 	 * unpin scan buffers
@@ -1553,7 +1554,7 @@ heap_rescan(HeapScanDesc scan,
 	/*
 	 * reinitialize scan descriptor
 	 */
-	initscan(scan, key, true);
+	initscan(scan, key, keep_startblock);
 }
 
 /* ----------------
@@ -1574,7 +1575,7 @@ heap_rescan_set_params(HeapScanDesc scan, ScanKey key,
 	scan->rs_allow_sync = allow_sync;
 	scan->rs_pageatatime = allow_pagemode && IsMVCCSnapshot(scan->rs_snapshot);
 	/* ... and rescan */
-	heap_rescan(scan, key);
+	heap_rescan(scan, key, true);
 }
 
 /* ----------------
@@ -1772,6 +1773,29 @@ heap_beginscan_parallel(Relation relation, ParallelHeapScanDesc parallel_scan)
 }
 
 /* ----------------
+ *		heap_parallel_rescan		- restart a parallel relation scan
+ * ----------------
+ */
+void
+heap_parallel_rescan(ParallelHeapScanDesc pscan,
+					 HeapScanDesc scan)
+{
+	if (pscan != NULL)
+		scan->rs_parallel = pscan;
+
+	heap_rescan(scan,			/* scan desc */
+				NULL,			/* new scan keys */
+				false);			/* don't preserve start block */
+
+	/*
+	 * Ensure all the backends participating in parallel scan must share the
+	 * syncscan property.
+	 */
+	if (pscan)
+		scan->rs_syncscan = pscan->phs_syncscan;
+}
+
+/* ----------------
  *		heap_getnext	- retrieve next tuple in scan
  *
  *		Fix to work with index relations.
diff --git a/src/backend/executor/nodeBitmapHeapscan.c b/src/backend/executor/nodeBitmapHeapscan.c
index c784b9e..9131dae 100644
--- a/src/backend/executor/nodeBitmapHeapscan.c
+++ b/src/backend/executor/nodeBitmapHeapscan.c
@@ -452,7 +452,7 @@ ExecReScanBitmapHeapScan(BitmapHeapScanState *node)
 	PlanState  *outerPlan = outerPlanState(node);
 
 	/* rescan to release any page pin */
-	heap_rescan(node->ss.ss_currentScanDesc, NULL);
+	heap_rescan(node->ss.ss_currentScanDesc, NULL, true);
 
 	if (node->tbmiterator)
 		tbm_end_iterate(node->tbmiterator);
diff --git a/src/backend/executor/nodeSeqscan.c b/src/backend/executor/nodeSeqscan.c
index 3cb81fc..75607b2 100644
--- a/src/backend/executor/nodeSeqscan.c
+++ b/src/backend/executor/nodeSeqscan.c
@@ -268,7 +268,8 @@ ExecReScanSeqScan(SeqScanState *node)
 	scan = node->ss_currentScanDesc;
 
 	heap_rescan(scan,			/* scan desc */
-				NULL);			/* new scan keys */
+				NULL,			/* new scan keys */
+				true);			/* preserve start block */
 
 	ExecScanReScan((ScanState *) node);
 }
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h
index 98a586d..894ee3f 100644
--- a/src/include/access/heapam.h
+++ b/src/include/access/heapam.h
@@ -121,9 +121,10 @@ extern HeapScanDesc heap_beginscan_sampling(Relation relation,
 extern void heap_setscanlimits(HeapScanDesc scan, BlockNumber startBlk,
 				   BlockNumber endBlk);
 extern void heapgetpage(HeapScanDesc scan, BlockNumber page);
-extern void heap_rescan(HeapScanDesc scan, ScanKey key);
+extern void heap_rescan(HeapScanDesc scan, ScanKey key, bool keep_startblock);
 extern void heap_rescan_set_params(HeapScanDesc scan, ScanKey key,
 					 bool allow_strat, bool allow_sync, bool allow_pagemode);
+extern void heap_parallel_rescan(ParallelHeapScanDesc pscan, HeapScanDesc scan);
 extern void heap_endscan(HeapScanDesc scan);
 extern HeapTuple heap_getnext(HeapScanDesc scan, ScanDirection direction);