linux-zen-desktop/tools/testing/selftests/powerpc/mm/prot_sao.c

49 lines
1.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2016, Michael Ellerman, IBM Corp.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
#include <asm/cputable.h>
#include "utils.h"
#define SIZE (64 * 1024)
int test_prot_sao(void)
{
char *p;
/*
* SAO was introduced in 2.06 and removed in 3.1. It's disabled in
* guests/LPARs by default, so also skip if we are running in a guest.
*/
SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06) ||
have_hwcap2(PPC_FEATURE2_ARCH_3_1) ||
access("/proc/device-tree/rtas/ibm,hypertas-functions", F_OK) == 0);
/*
* Ensure we can ask for PROT_SAO.
* We can't really verify that it does the right thing, but at least we
* confirm the kernel will accept it.
*/
p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE | PROT_SAO,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
FAIL_IF(p == MAP_FAILED);
/* Write to the mapping, to at least cause a fault */
memset(p, 0xaa, SIZE);
return 0;
}
int main(void)
{
return test_harness(test_prot_sao, "prot-sao");
}