On Wed, Apr 12, 2023 at 12:42:57PM -0400, Peter Xu wrote:
> Add one simple test for UFFDIO_API. With that, I also added a bunch of
> small but handy helpers along the way.
>
> Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Reviewed-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
> ---
> tools/testing/selftests/mm/uffd-unit-tests.c | 109 ++++++++++++++++++-
> 1 file changed, 108 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c
> index 6857388783be..bb492c258486 100644
> --- a/tools/testing/selftests/mm/uffd-unit-tests.c
> +++ b/tools/testing/selftests/mm/uffd-unit-tests.c
> @@ -9,9 +9,116 @@
>
> #ifdef __NR_userfaultfd
>
> +static void uffd_test_report(void)
> +{
> + printf("Userfaults unit tests: pass=%u, skip=%u, fail=%u (total=%u)\n",
> + ksft_get_pass_cnt(),
> + ksft_get_xskip_cnt(),
> + ksft_get_fail_cnt(),
> + ksft_test_num());
> +}
> +
> +static void uffd_test_pass(void)
> +{
> + printf("done\n");
> + ksft_inc_pass_cnt();
> +}
> +
> +#define uffd_test_start(...) do { \
> + printf("Testing "); \
> + printf(__VA_ARGS__); \
> + printf("... "); \
> + fflush(stdout); \
> + } while (0)
> +
> +#define uffd_test_fail(...) do { \
> + printf("failed [reason: "); \
> + printf(__VA_ARGS__); \
> + printf("]\n"); \
> + ksft_inc_fail_cnt(); \
> + } while (0)
> +
> +#define uffd_test_skip(...) do { \
> + printf("skipped [reason: "); \
> + printf(__VA_ARGS__); \
> + printf("]\n"); \
> + ksft_inc_xskip_cnt(); \
> + } while (0)
> +
> +/*
> + * Returns 1 if specific userfaultfd supported, 0 otherwise. Note, we'll
> + * return 1 even if some test failed as long as uffd supported, because in
> + * that case we still want to proceed with the rest uffd unit tests.
> + */
> +static int test_uffd_api(bool use_dev)
> +{
> + struct uffdio_api uffdio_api;
> + int uffd;
> +
> + uffd_test_start("UFFDIO_API (with %s)",
> + use_dev ? "/dev/userfaultfd" : "syscall");
> +
> + if (use_dev)
> + uffd = uffd_open_dev(UFFD_FLAGS);
> + else
> + uffd = uffd_open_sys(UFFD_FLAGS);
> + if (uffd < 0) {
> + uffd_test_skip("cannot open userfaultfd handle");
> + return 0;
> + }
> +
> + /* Test wrong UFFD_API */
> + uffdio_api.api = 0xab;
> + uffdio_api.features = 0;
> + if (ioctl(uffd, UFFDIO_API, &uffdio_api) == 0) {
> + uffd_test_fail("UFFDIO_API should fail with wrong api but didn't");
> + goto out;
> + }
> +
> + /* Test wrong feature bit */
> + uffdio_api.api = UFFD_API;
> + uffdio_api.features = BIT_ULL(63);
> + if (ioctl(uffd, UFFDIO_API, &uffdio_api) == 0) {
> + uffd_test_fail("UFFDIO_API should fail with wrong feature but didn't");
> + goto out;
> + }
> +
> + /* Test normal UFFDIO_API */
> + uffdio_api.api = UFFD_API;
> + uffdio_api.features = 0;
> + if (ioctl(uffd, UFFDIO_API, &uffdio_api)) {
> + uffd_test_fail("UFFDIO_API should succeed but failed");
> + goto out;
> + }
> +
> + /* Test double requests of UFFDIO_API with a random feature set */
> + uffdio_api.features = BIT_ULL(0);
> + if (ioctl(uffd, UFFDIO_API, &uffdio_api) == 0) {
> + uffd_test_fail("UFFDIO_API should reject initialized uffd");
> + goto out;
> + }
> +
> + uffd_test_pass();
> +out:
> + close(uffd);
> + /* We have a valid uffd handle */
> + return 1;
> +}
> +
> int main(int argc, char *argv[])
> {
> - return KSFT_PASS;
> + int has_uffd;
> +
> + has_uffd = test_uffd_api(false);
> + has_uffd |= test_uffd_api(true);
> +
> + if (!has_uffd) {
> + printf("Userfaultfd not supported or unprivileged, skip all tests\n");
> + exit(KSFT_SKIP);
> + }
> + uffd_test_report();
> +
> + return ksft_get_fail_cnt() ? KSFT_FAIL : KSFT_PASS;
> }
>
> #else /* __NR_userfaultfd */
> --
> 2.39.1
>
--
Sincerely yours,
Mike.
