Re: [PATCH v4 2/3] selftests: soft-dirty: Add test for mprotect

David Hildenbrand
2022-07-25T14:28:18Z

On 25.07.22 16:20, Peter Xu wrote:
> Add two soft-dirty test cases for mprotect() on both anon or file.
>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
> tools/testing/selftests/vm/soft-dirty.c | 67 ++++++++++++++++++++++++-
> 1 file changed, 66 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/vm/soft-dirty.c b/tools/testing/selftests/vm/soft-dirty.c
> index 08ab62a4a9d0..e3a43f5d4fa2 100644
> --- a/tools/testing/selftests/vm/soft-dirty.c
> +++ b/tools/testing/selftests/vm/soft-dirty.c
> @@ -121,13 +121,76 @@ static void test_hugepage(int pagemap_fd, int pagesize)
> free(map);
> }
>
> +static void test_mprotect(int pagemap_fd, int pagesize, bool anon)
> +{
> + const char *type[] = {"file", "anon"};
> + const char *fname = "./soft-dirty-test-file";
> + int test_fd;
> + char *map;
> +
> + if (anon) {
> + map = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
> + MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
> + if (!map)
> + ksft_exit_fail_msg("anon mmap failed\n");
> + } else {
> + test_fd = open(fname, O_RDWR | O_CREAT);
> + if (test_fd < 0) {
> + ksft_test_result_skip("Test %s open() file failed\n", __func__);
> + return;
> + }
> + unlink(fname);
> + ftruncate(test_fd, pagesize);
> + map = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
> + MAP_SHARED, test_fd, 0);
> + if (!map)
> + ksft_exit_fail_msg("file mmap failed\n");
> + }
> +
> + *map = 1;
> + ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 1,
> + "Test %s-%s dirty bit of new written page\n",
> + __func__, type[anon]);
> + clear_softdirty();
> + ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 0,
> + "Test %s-%s soft-dirty clear after clear_refs\n",
> + __func__, type[anon]);
> + mprotect(map, pagesize, PROT_READ);
> + ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 0,
> + "Test %s-%s soft-dirty clear after marking RO\n",
> + __func__, type[anon]);
> + mprotect(map, pagesize, PROT_READ|PROT_WRITE);
> + ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 0,
> + "Test %s-%s soft-dirty clear after marking RW\n",
> + __func__, type[anon]);
> + *map = 2;
> + ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 1,
> + "Test %s-%s soft-dirty after rewritten\n",
> + __func__, type[anon]);
> +
> + munmap(map, pagesize);
> +
> + if (!anon)
> + close(test_fd);
> +}
> +
> +static void test_mprotect_anon(int pagemap_fd, int pagesize)
> +{
> + test_mprotect(pagemap_fd, pagesize, true);
> +}
> +
> +static void test_mprotect_file(int pagemap_fd, int pagesize)
> +{
> + test_mprotect(pagemap_fd, pagesize, false);
> +}
> +
> int main(int argc, char **argv)
> {
> int pagemap_fd;
> int pagesize;
>
> ksft_print_header();
> - ksft_set_plan(5);
> + ksft_set_plan(15);
>
> pagemap_fd = open(PAGEMAP_FILE_PATH, O_RDONLY);
> if (pagemap_fd < 0)
> @@ -138,6 +201,8 @@ int main(int argc, char **argv)
> test_simple(pagemap_fd, pagesize);
> test_vma_reuse(pagemap_fd, pagesize);
> test_hugepage(pagemap_fd, pagesize);
> + test_mprotect_anon(pagemap_fd, pagesize);
> + test_mprotect_file(pagemap_fd, pagesize);
>
> close(pagemap_fd);
>

Reviewed-by: David Hildenbrand <david@redhat.com>

--
Thanks,

David / dhildenb