Don't include unused space in LOG_NEWPAGE records.

This is the same trick we use when taking a full page image of a buffer
passed to XLogInsert.

src/backend/commands/tablecmds.c

@@ -9130,9 +9130,13 @@ copy_relation_data(SMgrRelation src, SMgrRelation dst,
 										   src->smgr_rnode.backend,
 										   forkNum))));
 
-		/* XLOG stuff */
+		/*
+		 * WAL-log the copied page. Unfortunately we don't know what kind of
+		 * a page this is, so we have to log the full page including any
+		 * unused space.
+		 */
 		if (use_wal)
-			log_newpage(&dst->smgr_rnode.node, forkNum, blkno, page);
+			log_newpage(&dst->smgr_rnode.node, forkNum, blkno, page, false);
 
 		PageSetChecksumInplace(page, blkno);
 

src/backend/commands/vacuumlazy.c

@@ -699,14 +699,10 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
 				 * which will cause a PANIC.  To prevent that, check whether
 				 * the page has been previously WAL-logged, and if not, do that
 				 * now.
-				 *
-				 * XXX: It would be nice to use a logging method supporting
-				 * standard buffers here since log_newpage_buffer() will write
-				 * the full block instead of omitting the hole.
 				 */
 				if (RelationNeedsWAL(onerel) &&
 					PageGetLSN(page) == InvalidXLogRecPtr)
-					log_newpage_buffer(buf);
+					log_newpage_buffer(buf, true);
 
 				PageSetAllVisible(page);
 				visibilitymap_set(onerel, blkno, buf, InvalidXLogRecPtr,