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

Peter Xu
2022-07-25T14:21:01Z

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);

--
2.32.0