selftests: soft-dirty: add test for mprotect

Add two soft-dirty test cases for mprotect() on both anon or file.

Link: https://lkml.kernel.org/r/20220725142048.30450-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/tools/testing/selftests/vm/soft-dirty.c b/tools/testing/selftests/vm/soft-dirty.c
index 08ab62a4a9d071095649765661e71bcd7f9e6be7..e3a43f5d4fa2bb8f3916161a0efb0eb39ac657f8 100644 (file)
--- 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);