diff --git a/contrib/pageinspect/gistfuncs.c b/contrib/pageinspect/gistfuncs.c
index 100697814d..2b252f85bd 100644
--- a/contrib/pageinspect/gistfuncs.c
+++ b/contrib/pageinspect/gistfuncs.c
@@ -32,13 +32,14 @@ PG_FUNCTION_INFO_V1(gist_page_items_bytea);
 #define IS_GIST(r) ((r)->rd_rel->relam == GIST_AM_OID)
 
 
+static Page verify_gist_page(bytea *raw_page);
+
 Datum
 gist_page_opaque_info(PG_FUNCTION_ARGS)
 {
 	bytea	   *raw_page = PG_GETARG_BYTEA_P(0);
 	TupleDesc	tupdesc;
 	Page		page;
-	GISTPageOpaque opaq;
 	HeapTuple	resultTuple;
 	Datum		values[4];
 	bool		nulls[4];
@@ -51,35 +52,17 @@ gist_page_opaque_info(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 				 errmsg("must be superuser to use raw page functions")));
 
-	page = get_page_from_raw(raw_page);
+	page = verify_gist_page(raw_page);
 
 	if (PageIsNew(page))
 		PG_RETURN_NULL();
 
-	/* verify the special space has the expected size */
-	if (PageGetSpecialSize(page) != MAXALIGN(sizeof(GISTPageOpaqueData)))
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("input page is not a valid %s page", "GiST"),
-				 errdetail("Expected special size %d, got %d.",
-						   (int) MAXALIGN(sizeof(GISTPageOpaqueData)),
-						   (int) PageGetSpecialSize(page))));
-
-	opaq = GistPageGetOpaque(page);
-	if (opaq->gist_page_id != GIST_PAGE_ID)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("input page is not a valid %s page", "GiST"),
-				 errdetail("Expected %08x, got %08x.",
-						   GIST_PAGE_ID,
-						   opaq->gist_page_id)));
-
 	/* Build a tuple descriptor for our result type */
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
 	/* Convert the flags bitmask to an array of human-readable names */
-	flagbits = opaq->flags;
+	flagbits = GistPageGetOpaque(page)->flags;
 	if (flagbits & F_LEAF)
 		flags[nflags++] = CStringGetTextDatum("leaf");
 	if (flagbits & F_DELETED)
@@ -101,7 +84,7 @@ gist_page_opaque_info(PG_FUNCTION_ARGS)
 
 	values[0] = LSNGetDatum(PageGetLSN(page));
 	values[1] = LSNGetDatum(GistPageGetNSN(page));
-	values[2] = Int64GetDatum(opaq->rightlink);
+	values[2] = Int64GetDatum(GistPageGetOpaque(page)->rightlink);
 	values[3] = PointerGetDatum(construct_array_builtin(flags, nflags, TEXTOID));
 
 	/* Build and return the result tuple. */
@@ -116,7 +99,6 @@ gist_page_items_bytea(PG_FUNCTION_ARGS)
 	bytea	   *raw_page = PG_GETARG_BYTEA_P(0);
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
 	Page		page;
-	GISTPageOpaque opaq;
 	OffsetNumber offset;
 	OffsetNumber maxoff = InvalidOffsetNumber;
 
@@ -127,29 +109,11 @@ gist_page_items_bytea(PG_FUNCTION_ARGS)
 
 	InitMaterializedSRF(fcinfo, 0);
 
-	page = get_page_from_raw(raw_page);
+	page = verify_gist_page(raw_page);
 
 	if (PageIsNew(page))
 		PG_RETURN_NULL();
 
-	/* verify the special space has the expected size */
-	if (PageGetSpecialSize(page) != MAXALIGN(sizeof(GISTPageOpaqueData)))
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("input page is not a valid %s page", "GiST"),
-				 errdetail("Expected special size %d, got %d.",
-						   (int) MAXALIGN(sizeof(GISTPageOpaqueData)),
-						   (int) PageGetSpecialSize(page))));
-
-	opaq = GistPageGetOpaque(page);
-	if (opaq->gist_page_id != GIST_PAGE_ID)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("input page is not a valid %s page", "GiST"),
-				 errdetail("Expected %08x, got %08x.",
-						   GIST_PAGE_ID,
-						   opaq->gist_page_id)));
-
 	/* Avoid bogus PageGetMaxOffsetNumber() call with deleted pages */
 	if (GistPageIsDeleted(page))
 		elog(NOTICE, "page is deleted");
@@ -193,6 +157,40 @@ gist_page_items_bytea(PG_FUNCTION_ARGS)
 	return (Datum) 0;
 }
 
+/*
+ * Verify that the given bytea contains a GIST page or die in the attempt.
+ * A pointer to the page is returned.
+ */
+static Page
+verify_gist_page(bytea *raw_page)
+{
+	Page		page = get_page_from_raw(raw_page);
+	GISTPageOpaque opaq;
+
+	if (PageIsNew(page))
+		return page;
+
+	/* verify the special space has the expected size */
+	if (PageGetSpecialSize(page) != MAXALIGN(sizeof(GISTPageOpaqueData)))
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("input page is not a valid %s page", "GiST"),
+				 errdetail("Expected special size %d, got %d.",
+						   (int) MAXALIGN(sizeof(GISTPageOpaqueData)),
+						   (int) PageGetSpecialSize(page))));
+
+	opaq = GistPageGetOpaque(page);
+	if (opaq->gist_page_id != GIST_PAGE_ID)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("input page is not a valid %s page", "GiST"),
+				 errdetail("Expected %08x, got %08x.",
+						   GIST_PAGE_ID,
+						   opaq->gist_page_id)));
+
+	return page;
+}
+
 Datum
 gist_page_items(PG_FUNCTION_ARGS)
 {
@@ -220,7 +218,7 @@ gist_page_items(PG_FUNCTION_ARGS)
 				 errmsg("\"%s\" is not a %s index",
 						RelationGetRelationName(indexRel), "GiST")));
 
-	page = get_page_from_raw(raw_page);
+	page = verify_gist_page(raw_page);
 
 	if (PageIsNew(page))
 	{