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> --- 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