WAL redo checksum

neon_wal_redo.c

 // @@ -569,6 +569,21 @@ PushPage(StringInfo input_message)
	/*
	 * Every backend on the compute side will verify the page checksum
	 * after reading it from pageserver using GetPage@LSN. Here in the
	 * WAL redo process we are reading pages directly from stdin, so we
	 * would better verify checksum too before applying any WAL records
	 * on top of it.
	 */
	if (!PageIsVerifiedExtended((Page) content, blknum,
								PIV_LOG_WARNING | PIV_REPORT_STAT))
		ereport(ERROR,
				(errcode(ERRCODE_DATA_CORRUPTED),
					errmsg("invalid page in block %u of relation %s",
						   blknum,
						   relpathperm(rnode, forknum))));

// @@ -614,6 +629,14 @@ ApplyRecord(StringInfo input_message)
	/*
	 * Validate CRC of the WAL record, because DecodeXLogRecord() doesn not
	 * check it. It is only validated in the XLogReadRecord(), which we do
	 * not use.
	 */
	if (!ValidXLogRecord(&reader_state, record, reader_state.EndRecPtr))
		elog(ERROR, "failed to verify WAL record checksum: %s", reader_state.errormsg_buf);