Commit c942f5bd authored by Peter Xu's avatar Peter Xu Committed by Andrew Morton
Browse files

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: default avatarPeter Xu <peterx@redhat.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 76aefad6

tools/testing/selftests/vm/soft-dirty.c

+66 −1
Original line number Diff line number Diff line
@@ -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);