diff --git a/contrib/pageinspect/brinfuncs.c b/contrib/pageinspect/brinfuncs.c
index f4f0dea860f..fa512aec936 100644
--- a/contrib/pageinspect/brinfuncs.c
+++ b/contrib/pageinspect/brinfuncs.c
@@ -18,6 +18,7 @@
 #include "access/brin_revmap.h"
 #include "access/brin_tuple.h"
 #include "catalog/index.h"
+#include "catalog/pg_am_d.h"
 #include "catalog/pg_type.h"
 #include "funcapi.h"
 #include "lib/stringinfo.h"
@@ -33,6 +34,8 @@ PG_FUNCTION_INFO_V1(brin_page_items);
 PG_FUNCTION_INFO_V1(brin_metapage_info);
 PG_FUNCTION_INFO_V1(brin_revmap_data);
 
+#define IS_BRIN(r) ((r)->rd_rel->relam == BRIN_AM_OID)
+
 typedef struct brin_column_state
 {
 	int			nstored;
@@ -47,8 +50,7 @@ Datum
 brin_page_type(PG_FUNCTION_ARGS)
 {
 	bytea	   *raw_page = PG_GETARG_BYTEA_P(0);
-	Page		page = VARDATA(raw_page);
-	int			raw_page_size;
+	Page		page;
 	char	   *type;
 
 	if (!superuser())
@@ -56,14 +58,7 @@ brin_page_type(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 				 (errmsg("must be superuser to use raw page functions"))));
 
-	raw_page_size = VARSIZE(raw_page) - VARHDRSZ;
-
-	if (raw_page_size != BLCKSZ)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("input page too small"),
-				 errdetail("Expected size %d, got %d",
-						   BLCKSZ, raw_page_size)));
+	page = get_page_from_raw(raw_page);
 
 	switch (BrinPageType(page))
 	{
@@ -91,19 +86,7 @@ brin_page_type(PG_FUNCTION_ARGS)
 static Page
 verify_brin_page(bytea *raw_page, uint16 type, const char *strtype)
 {
-	Page		page;
-	int			raw_page_size;
-
-	raw_page_size = VARSIZE(raw_page) - VARHDRSZ;
-
-	if (raw_page_size != BLCKSZ)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("input page too small"),
-				 errdetail("Expected size %d, got %d",
-						   BLCKSZ, raw_page_size)));
-
-	page = VARDATA(raw_page);
+	Page		page = get_page_from_raw(raw_page);
 
 	/* verify the special space says this page is what we want */
 	if (BrinPageType(page) != type)
@@ -171,6 +154,13 @@ brin_page_items(PG_FUNCTION_ARGS)
 	MemoryContextSwitchTo(oldcontext);
 
 	indexRel = index_open(indexRelid, AccessShareLock);
+
+	if (!IS_BRIN(indexRel))
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("\"%s\" is not a %s index",
+						RelationGetRelationName(indexRel), "BRIN")));
+
 	bdesc = brin_build_desc(indexRel);
 
 	/* minimally verify the page we got */
diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c
index 439d706edee..33d809f4f69 100644
--- a/contrib/pageinspect/btreefuncs.c
+++ b/contrib/pageinspect/btreefuncs.c
@@ -181,8 +181,10 @@ bt_page_stats(PG_FUNCTION_ARGS)
 	rel = relation_openrv(relrv, AccessShareLock);
 
 	if (!IS_INDEX(rel) || !IS_BTREE(rel))
-		elog(ERROR, "relation \"%s\" is not a btree index",
-			 RelationGetRelationName(rel));
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("\"%s\" is not a %s index",
+						RelationGetRelationName(rel), "btree")));
 
 	/*
 	 * Reject attempts to read non-local temporary relations; we would be
@@ -335,8 +337,10 @@ bt_page_items(PG_FUNCTION_ARGS)
 		rel = relation_openrv(relrv, AccessShareLock);
 
 		if (!IS_INDEX(rel) || !IS_BTREE(rel))
-			elog(ERROR, "relation \"%s\" is not a btree index",
-				 RelationGetRelationName(rel));
+			ereport(ERROR,
+					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					 errmsg("\"%s\" is not a %s index",
+							RelationGetRelationName(rel), "btree")));
 
 		/*
 		 * Reject attempts to read non-local temporary relations; we would be
@@ -424,7 +428,6 @@ bt_page_items_bytea(PG_FUNCTION_ARGS)
 	Datum		result;
 	FuncCallContext *fctx;
 	struct user_args *uargs;
-	int			raw_page_size;
 
 	if (!superuser())
 		ereport(ERROR,
@@ -437,19 +440,12 @@ bt_page_items_bytea(PG_FUNCTION_ARGS)
 		MemoryContext mctx;
 		TupleDesc	tupleDesc;
 
-		raw_page_size = VARSIZE(raw_page) - VARHDRSZ;
-
-		if (raw_page_size < SizeOfPageHeaderData)
-			ereport(ERROR,
-					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-					 errmsg("input page too small (%d bytes)", raw_page_size)));
-
 		fctx = SRF_FIRSTCALL_INIT();
 		mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);
 
 		uargs = palloc(sizeof(struct user_args));
 
-		uargs->page = VARDATA(raw_page);
+		uargs->page = get_page_from_raw(raw_page);
 
 		uargs->offset = FirstOffsetNumber;
 
@@ -525,8 +521,10 @@ bt_metap(PG_FUNCTION_ARGS)
 	rel = relation_openrv(relrv, AccessShareLock);
 
 	if (!IS_INDEX(rel) || !IS_BTREE(rel))
-		elog(ERROR, "relation \"%s\" is not a btree index",
-			 RelationGetRelationName(rel));
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("\"%s\" is not a %s index",
+						RelationGetRelationName(rel), "btree")));
 
 	/*
 	 * Reject attempts to read non-local temporary relations; we would be
diff --git a/contrib/pageinspect/expected/brin.out b/contrib/pageinspect/expected/brin.out
index 71eb190380c..10cd36c1778 100644
--- a/contrib/pageinspect/expected/brin.out
+++ b/contrib/pageinspect/expected/brin.out
@@ -48,4 +48,8 @@ SELECT * FROM brin_page_items(get_raw_page('test1_a_idx', 2), 'test1_a_idx')
           1 |      0 |      1 | f        | f        | f           | {1 .. 1}
 (1 row)
 
+-- Failure for non-BRIN index.
+CREATE INDEX test1_a_btree ON test1 (a);
+SELECT brin_page_items(get_raw_page('test1_a_btree', 0), 'test1_a_btree');
+ERROR:  "test1_a_btree" is not a BRIN index
 DROP TABLE test1;
diff --git a/contrib/pageinspect/expected/btree.out b/contrib/pageinspect/expected/btree.out
index 2aaa4df53b1..da86c12846b 100644
--- a/contrib/pageinspect/expected/btree.out
+++ b/contrib/pageinspect/expected/btree.out
@@ -57,4 +57,19 @@ data       | 01 00 00 00 00 00 00 01
 
 SELECT * FROM bt_page_items(get_raw_page('test1_a_idx', 2));
 ERROR:  block number 2 is out of range for relation "test1_a_idx"
+-- Failure when using a non-btree index.
+CREATE INDEX test1_a_hash ON test1 USING hash(a);
+SELECT bt_metap('test1_a_hash');
+ERROR:  "test1_a_hash" is not a btree index
+SELECT bt_page_stats('test1_a_hash', 0);
+ERROR:  "test1_a_hash" is not a btree index
+SELECT bt_page_items('test1_a_hash', 0);
+ERROR:  "test1_a_hash" is not a btree index
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT bt_page_items('aaa'::bytea);
+ERROR:  invalid page size
+\set VERBOSITY default
 DROP TABLE test1;
diff --git a/contrib/pageinspect/expected/gin.out b/contrib/pageinspect/expected/gin.out
index 82f63b23b19..c0f75950987 100644
--- a/contrib/pageinspect/expected/gin.out
+++ b/contrib/pageinspect/expected/gin.out
@@ -35,3 +35,14 @@ FROM gin_leafpage_items(get_raw_page('test1_y_idx',
 -[ RECORD 1 ]
 ?column? | t
 
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT gin_leafpage_items('aaa'::bytea);
+ERROR:  invalid page size
+SELECT gin_metapage_info('bbb'::bytea);
+ERROR:  invalid page size
+SELECT gin_page_opaque_info('ccc'::bytea);
+ERROR:  invalid page size
+\set VERBOSITY default
diff --git a/contrib/pageinspect/expected/hash.out b/contrib/pageinspect/expected/hash.out
index 75d7bcfad5f..12369ddfa29 100644
--- a/contrib/pageinspect/expected/hash.out
+++ b/contrib/pageinspect/expected/hash.out
@@ -159,4 +159,21 @@ SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 4));
 
 SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 5));
 ERROR:  page is not a hash bucket or overflow page
+-- Failure with non-hash index
+CREATE INDEX test_hash_a_btree ON test_hash USING btree (a);
+SELECT hash_bitmap_info('test_hash_a_btree', 0);
+ERROR:  "test_hash_a_btree" is not a hash index
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT hash_metapage_info('aaa'::bytea);
+ERROR:  invalid page size
+SELECT hash_page_items('bbb'::bytea);
+ERROR:  invalid page size
+SELECT hash_page_stats('ccc'::bytea);
+ERROR:  invalid page size
+SELECT hash_page_type('ddd'::bytea);
+ERROR:  invalid page size
+\set VERBOSITY default
 DROP TABLE test_hash;
diff --git a/contrib/pageinspect/expected/page.out b/contrib/pageinspect/expected/page.out
index e4e0c221dba..75d7e8232b4 100644
--- a/contrib/pageinspect/expected/page.out
+++ b/contrib/pageinspect/expected/page.out
@@ -113,3 +113,14 @@ select tuple_data_split('test8'::regclass, t_data, t_infomask, t_infomask2, t_bi
 (1 row)
 
 drop table test8;
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT fsm_page_contents('aaa'::bytea);
+ERROR:  invalid page size
+SELECT page_checksum('bbb'::bytea, 0);
+ERROR:  invalid page size
+SELECT page_header('ccc'::bytea);
+ERROR:  invalid page size
+\set VERBOSITY default
diff --git a/contrib/pageinspect/fsmfuncs.c b/contrib/pageinspect/fsmfuncs.c
index 86e8075845e..788c6fb397c 100644
--- a/contrib/pageinspect/fsmfuncs.c
+++ b/contrib/pageinspect/fsmfuncs.c
@@ -37,6 +37,7 @@ fsm_page_contents(PG_FUNCTION_ARGS)
 {
 	bytea	   *raw_page = PG_GETARG_BYTEA_P(0);
 	StringInfoData sinfo;
+	Page		page;
 	FSMPage		fsmpage;
 	int			i;
 
@@ -45,7 +46,8 @@ fsm_page_contents(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 				 (errmsg("must be superuser to use raw page functions"))));
 
-	fsmpage = (FSMPage) PageGetContents(VARDATA(raw_page));
+	page = get_page_from_raw(raw_page);
+	fsmpage = (FSMPage) PageGetContents(page);
 
 	initStringInfo(&sinfo);
 
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index c49adf207cb..c188a68bc29 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -420,8 +420,10 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 	indexRel = index_open(indexRelid, AccessShareLock);
 
 	if (!IS_HASH(indexRel))
-		elog(ERROR, "relation \"%s\" is not a hash index",
-			 RelationGetRelationName(indexRel));
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("\"%s\" is not a %s index",
+						RelationGetRelationName(indexRel), "hash")));
 
 	if (RELATION_IS_OTHER_TEMP(indexRel))
 		ereport(ERROR,
diff --git a/contrib/pageinspect/rawpage.c b/contrib/pageinspect/rawpage.c
index d7bf782ccd5..072f1efe221 100644
--- a/contrib/pageinspect/rawpage.c
+++ b/contrib/pageinspect/rawpage.c
@@ -218,7 +218,6 @@ Datum
 page_header(PG_FUNCTION_ARGS)
 {
 	bytea	   *raw_page = PG_GETARG_BYTEA_P(0);
-	int			raw_page_size;
 
 	TupleDesc	tupdesc;
 
@@ -235,18 +234,7 @@ page_header(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 				 (errmsg("must be superuser to use raw page functions"))));
 
-	raw_page_size = VARSIZE(raw_page) - VARHDRSZ;
-
-	/*
-	 * Check that enough data was supplied, so that we don't try to access
-	 * fields outside the supplied buffer.
-	 */
-	if (raw_page_size < SizeOfPageHeaderData)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("input page too small (%d bytes)", raw_page_size)));
-
-	page = (PageHeader) VARDATA(raw_page);
+	page = (PageHeader) get_page_from_raw(raw_page);
 
 	/* Build a tuple descriptor for our result type */
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
@@ -299,25 +287,14 @@ page_checksum(PG_FUNCTION_ARGS)
 {
 	bytea	   *raw_page = PG_GETARG_BYTEA_P(0);
 	uint32		blkno = PG_GETARG_INT32(1);
-	int			raw_page_size;
-	PageHeader	page;
+	Page		page;
 
 	if (!superuser())
 		ereport(ERROR,
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 				 (errmsg("must be superuser to use raw page functions"))));
 
-	raw_page_size = VARSIZE(raw_page) - VARHDRSZ;
-
-	/*
-	 * Check that the supplied page is of the right size.
-	 */
-	if (raw_page_size != BLCKSZ)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("incorrect size of input page (%d bytes)", raw_page_size)));
-
-	page = (PageHeader) VARDATA(raw_page);
+	page = get_page_from_raw(raw_page);
 
 	PG_RETURN_INT16(pg_checksum_page((char *) page, blkno));
 }
diff --git a/contrib/pageinspect/sql/brin.sql b/contrib/pageinspect/sql/brin.sql
index 735bc3b6733..8717229c5d2 100644
--- a/contrib/pageinspect/sql/brin.sql
+++ b/contrib/pageinspect/sql/brin.sql
@@ -15,4 +15,8 @@ SELECT * FROM brin_revmap_data(get_raw_page('test1_a_idx', 1)) LIMIT 5;
 SELECT * FROM brin_page_items(get_raw_page('test1_a_idx', 2), 'test1_a_idx')
     ORDER BY blknum, attnum LIMIT 5;
 
+-- Failure for non-BRIN index.
+CREATE INDEX test1_a_btree ON test1 (a);
+SELECT brin_page_items(get_raw_page('test1_a_btree', 0), 'test1_a_btree');
+
 DROP TABLE test1;
diff --git a/contrib/pageinspect/sql/btree.sql b/contrib/pageinspect/sql/btree.sql
index 8eac64c7b3c..174814fb7a4 100644
--- a/contrib/pageinspect/sql/btree.sql
+++ b/contrib/pageinspect/sql/btree.sql
@@ -18,4 +18,17 @@ SELECT * FROM bt_page_items(get_raw_page('test1_a_idx', 0));
 SELECT * FROM bt_page_items(get_raw_page('test1_a_idx', 1));
 SELECT * FROM bt_page_items(get_raw_page('test1_a_idx', 2));
 
+-- Failure when using a non-btree index.
+CREATE INDEX test1_a_hash ON test1 USING hash(a);
+SELECT bt_metap('test1_a_hash');
+SELECT bt_page_stats('test1_a_hash', 0);
+SELECT bt_page_items('test1_a_hash', 0);
+
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT bt_page_items('aaa'::bytea);
+\set VERBOSITY default
+
 DROP TABLE test1;
diff --git a/contrib/pageinspect/sql/gin.sql b/contrib/pageinspect/sql/gin.sql
index d516ed3cbd4..2a653609750 100644
--- a/contrib/pageinspect/sql/gin.sql
+++ b/contrib/pageinspect/sql/gin.sql
@@ -17,3 +17,12 @@ SELECT COUNT(*) > 0
 FROM gin_leafpage_items(get_raw_page('test1_y_idx',
                         (pg_relation_size('test1_y_idx') /
                          current_setting('block_size')::bigint)::int - 1));
+
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT gin_leafpage_items('aaa'::bytea);
+SELECT gin_metapage_info('bbb'::bytea);
+SELECT gin_page_opaque_info('ccc'::bytea);
+\set VERBOSITY default
diff --git a/contrib/pageinspect/sql/hash.sql b/contrib/pageinspect/sql/hash.sql
index 87ee549a7b4..546c780e0e4 100644
--- a/contrib/pageinspect/sql/hash.sql
+++ b/contrib/pageinspect/sql/hash.sql
@@ -76,5 +76,18 @@ SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 3));
 SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 4));
 SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 5));
 
+-- Failure with non-hash index
+CREATE INDEX test_hash_a_btree ON test_hash USING btree (a);
+SELECT hash_bitmap_info('test_hash_a_btree', 0);
+
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT hash_metapage_info('aaa'::bytea);
+SELECT hash_page_items('bbb'::bytea);
+SELECT hash_page_stats('ccc'::bytea);
+SELECT hash_page_type('ddd'::bytea);
+\set VERBOSITY default
 
 DROP TABLE test_hash;
diff --git a/contrib/pageinspect/sql/page.sql b/contrib/pageinspect/sql/page.sql
index 42b69e62f52..dddb80b457c 100644
--- a/contrib/pageinspect/sql/page.sql
+++ b/contrib/pageinspect/sql/page.sql
@@ -52,3 +52,12 @@ select t_bits, t_data from heap_page_items(get_raw_page('test8', 0));
 select tuple_data_split('test8'::regclass, t_data, t_infomask, t_infomask2, t_bits)
     from heap_page_items(get_raw_page('test8', 0));
 drop table test8;
+
+-- Failure with incorrect page size
+-- Suppress the DETAIL message, to allow the tests to work across various
+-- page sizes.
+\set VERBOSITY terse
+SELECT fsm_page_contents('aaa'::bytea);
+SELECT page_checksum('bbb'::bytea, 0);
+SELECT page_header('ccc'::bytea);
+\set VERBOSITY default