diff --git a/contrib/pg_buffercache/pg_buffercache--1.0--1.1.sql b/contrib/pg_buffercache/pg_buffercache--1.0--1.1.sql
index 54d02f58c01..5e93238ff1e 100644
--- a/contrib/pg_buffercache/pg_buffercache--1.0--1.1.sql
+++ b/contrib/pg_buffercache/pg_buffercache--1.0--1.1.sql
@@ -6,6 +6,6 @@
 -- Upgrade view to 1.1. format
 CREATE OR REPLACE VIEW pg_buffercache AS
 	SELECT P.* FROM pg_buffercache_pages() AS P
-	(bufferid integer, relfilenode oid, reltablespace oid, reldatabase oid,
+	(bufferid integer, relfilenode int8, reltablespace oid, reldatabase oid,
 	 relforknumber int2, relblocknumber int8, isdirty bool, usagecount int2,
 	 pinning_backends int4);
diff --git a/contrib/pg_buffercache/pg_buffercache--1.2.sql b/contrib/pg_buffercache/pg_buffercache--1.2.sql
index 6ee5d8435bd..f52ddcde2b5 100644
--- a/contrib/pg_buffercache/pg_buffercache--1.2.sql
+++ b/contrib/pg_buffercache/pg_buffercache--1.2.sql
@@ -12,7 +12,7 @@ LANGUAGE C PARALLEL SAFE;
 -- Create a view for convenient access.
 CREATE VIEW pg_buffercache AS
 	SELECT P.* FROM pg_buffercache_pages() AS P
-	(bufferid integer, relfilenode oid, reltablespace oid, reldatabase oid,
+	(bufferid integer, relfilenode int8, reltablespace oid, reldatabase oid,
 	 relforknumber int2, relblocknumber int8, isdirty bool, usagecount int2,
 	 pinning_backends int4);
 
diff --git a/contrib/pg_buffercache/pg_buffercache_pages.c b/contrib/pg_buffercache/pg_buffercache_pages.c
index 4a870d62047..83d9bb0b850 100644
--- a/contrib/pg_buffercache/pg_buffercache_pages.c
+++ b/contrib/pg_buffercache/pg_buffercache_pages.c
@@ -209,7 +209,7 @@ pg_buffercache_pages(PG_FUNCTION_ARGS)
 		}
 		else
 		{
-			values[1] = ObjectIdGetDatum(fctx->record[i].relfilenode);
+			values[1] = Int64GetDatum(fctx->record[i].relfilenode);
 			nulls[1] = false;
 			values[2] = ObjectIdGetDatum(fctx->record[i].reltablespace);
 			nulls[2] = false;
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index 98e762c985b..68f243dcee7 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -817,7 +817,7 @@ index_create_internal(Relation heapRelation,
                       Oid indexRelationId,
                       Oid parentIndexRelid,
                       Oid parentConstraintId,
-                      Oid relFileNode,
+                      RelFileNodeId relFileNode,
                       IndexInfo *indexInfo,
                       List *indexColNames,
                       Oid accessMethodObjectId,
diff --git a/src/backend/commands/sequence.c b/src/backend/commands/sequence.c
index f3d9469e257..87fe223d6c6 100644
--- a/src/backend/commands/sequence.c
+++ b/src/backend/commands/sequence.c
@@ -99,7 +99,7 @@ SeqTableKey;
 typedef struct SeqTableData
 {
 	SeqTableKey	key;			/* sequence data hash key */
-	Oid			filenode;		/* last seen relfilenode of this sequence */
+	RelFileNodeId filenode;		/* last seen relfilenode of this sequence */
 	LocalTransactionId lxid;	/* xact in which we last did a seq op */
 	bool		last_valid;		/* do we have a valid "last" value? */
 	int64		last;			/* value last returned by nextval */
diff --git a/src/include/catalog/index.h b/src/include/catalog/index.h
index e13c88e14df..6c5204ec148 100644
--- a/src/include/catalog/index.h
+++ b/src/include/catalog/index.h
@@ -78,7 +78,7 @@ typedef Oid (*index_create_hook_type)(Relation heapRelation,
         Oid indexRelationId,
         Oid parentIndexRelid,
         Oid parentConstraintId,
-        Oid relFileNode,
+        RelFileNodeId relFileNode,
         IndexInfo *indexInfo,
         List *indexColNames,
         Oid accessMethodObjectId,
@@ -118,7 +118,7 @@ extern Oid index_create_internal(Relation heapRelation,
                                  Oid indexRelationId,
                                  Oid parentIndexRelid,
                                  Oid parentConstraintId,
-                                 Oid relFileNode,
+                                 RelFileNodeId relFileNode,
                                  IndexInfo *indexInfo,
                                  List *indexColNames,
                                  Oid accessMethodObjectId,