LXR linux/tools/testing/selftests/powerpc/mm/prot

   1/*
   2 * Copyright 2016, Michael Ellerman, IBM Corp.
   3 * Licensed under GPLv2.
   4 */
   5
   6#include <stdio.h>
   7#include <stdlib.h>
   8#include <string.h>
   9#include <sys/mman.h>
  10
  11#include <asm/cputable.h>
  12
  13#include "utils.h"
  14
  15#define SIZE (64 * 1024)
  16
  17int test_prot_sao(void)
  18{
  19        char *p;
  20
  21        /* 2.06 or later should support SAO */
  22        SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06));
  23
  24        /*
  25         * Ensure we can ask for PROT_SAO.
  26         * We can't really verify that it does the right thing, but at least we
  27         * confirm the kernel will accept it.
  28         */
  29        p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE | PROT_SAO,
  30                 MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
  31        FAIL_IF(p == MAP_FAILED);
  32
  33        /* Write to the mapping, to at least cause a fault */
  34        memset(p, 0xaa, SIZE);
  35
  36        return 0;
  37}
  38
  39int main(void)
  40{
  41        return test_harness(test_prot_sao, "prot-sao");
  42}
  43