From 785ebf3b029b7b79a90eb15ae2ddb9e984389fd7 Mon Sep 17 00:00:00 2001
From: Hubert Zhang <hzhang@pivotal.io>
Date: Mon, 10 Feb 2020 07:54:51 +0000
Subject: [PATCH] Print physical file path when checksum check fails

---
 src/backend/storage/buffer/bufmgr.c | 11 +++++++----
 src/common/relpath.c                | 27 +++++++++++++++++++++++++++
 src/include/common/relpath.h        | 21 +++++++++++++++++++++
 3 files changed, 55 insertions(+), 4 deletions(-)

diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index aba3960481..84308bd7a4 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -912,17 +912,20 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 				{
 					ereport(WARNING,
 							(errcode(ERRCODE_DATA_CORRUPTED),
-							 errmsg("invalid page in block %u of relation %s; zeroing out page",
+							 errmsg("invalid page in block %u of relation %s, "
+									"file path %s; zeroing out page",
 									blockNum,
-									relpath(smgr->smgr_rnode, forkNum))));
+									relpath(smgr->smgr_rnode, forkNum),
+									relfilepath(smgr->smgr_rnode, forkNum, blockNum))));
 					MemSet((char *) bufBlock, 0, BLCKSZ);
 				}
 				else
 					ereport(ERROR,
 							(errcode(ERRCODE_DATA_CORRUPTED),
-							 errmsg("invalid page in block %u of relation %s",
+							 errmsg("invalid page in block %u of relation %s, file path %s",
 									blockNum,
-									relpath(smgr->smgr_rnode, forkNum))));
+									relpath(smgr->smgr_rnode, forkNum),
+									relfilepath(smgr->smgr_rnode, forkNum, blockNum))));
 			}
 		}
 	}
diff --git a/src/common/relpath.c b/src/common/relpath.c
index ad733d1363..8b39c4ac4f 100644
--- a/src/common/relpath.c
+++ b/src/common/relpath.c
@@ -208,3 +208,30 @@ GetRelationPath(Oid dbNode, Oid spcNode, Oid relNode,
 	}
 	return path;
 }
+
+/*
+ * GetRelationFilePath - construct path to a relation's physical file
+ * given its block number.
+ */
+	char *
+GetRelationFilePath(Oid dbNode, Oid spcNode, Oid relNode,
+					int backendId, ForkNumber forkNumber, BlockNumber blkno)
+{
+	char	   *path;
+	char	   *fullpath;
+	BlockNumber	segno;
+
+	path = GetRelationPath(dbNode, spcNode, relNode, backendId, forkNumber);
+
+	segno = blkno / ((BlockNumber) RELSEG_SIZE);
+
+	if (segno > 0)
+	{
+		fullpath = psprintf("%s.%u", path, segno);
+		pfree(path);
+	}
+	else
+		fullpath = path;
+
+	return fullpath;
+}
diff --git a/src/include/common/relpath.h b/src/include/common/relpath.h
index 869cabcc0d..7e036f4086 100644
--- a/src/include/common/relpath.h
+++ b/src/include/common/relpath.h
@@ -13,6 +13,8 @@
 #ifndef RELPATH_H
 #define RELPATH_H
 
+#include "storage/block.h"
+
 /*
  *	'pgrminclude ignore' needed here because CppAsString2() does not throw
  *	an error if the symbol is not defined.
@@ -69,6 +71,9 @@ extern char *GetDatabasePath(Oid dbNode, Oid spcNode);
 extern char *GetRelationPath(Oid dbNode, Oid spcNode, Oid relNode,
 							 int backendId, ForkNumber forkNumber);
 
+extern char *GetRelationFilePath(Oid dbNode, Oid spcNode, Oid relNode,
+								 int backendId, ForkNumber forkNumber, BlockNumber blkno);
+
 /*
  * Wrapper macros for GetRelationPath.  Beware of multiple
  * evaluation of the RelFileNode or RelFileNodeBackend argument!
@@ -87,4 +92,20 @@ extern char *GetRelationPath(Oid dbNode, Oid spcNode, Oid relNode,
 #define relpath(rnode, forknum) \
 	relpathbackend((rnode).node, (rnode).backend, forknum)
 
+/*
+ * File path of a relation given the block number.
+ * Note that a file can contain at most RELSEG_SIZE number
+ * of blocks. We supply relfilepath macro to display the
+ * physical file name for a relation given the block number.
+ */
+
+/* First argument is a RelFileNode */
+#define relfilepathbackend(rnode, backend, forknum, blkno) \
+	GetRelationFilePath((rnode).dbNode, (rnode).spcNode, (rnode).relNode, \
+						backend, forknum, blkno)
+
+/* First argument is a RelFileNodeBackend */
+#define relfilepath(rnode, forknum, blkno) \
+	relfilepathbackend((rnode).node, (rnode).backend, forknum, blkno)
+
 #endif							/* RELPATH_H */
-- 
2.16.6