On Fri, May 19, 2023 at 12:27:23PM +0200, David Hildenbrand wrote:
> Similar to the COW selftests, also use io_uring fixed buffers to test
> if long-term page pinning works as expected.
>
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
> tools/testing/selftests/mm/gup_longterm.c | 73 +++++++++++++++++++++++
> 1 file changed, 73 insertions(+)
>
> diff --git a/tools/testing/selftests/mm/gup_longterm.c b/tools/testing/selftests/mm/gup_longterm.c
> index 44a3617fd423..d33d3e68ffab 100644
> --- a/tools/testing/selftests/mm/gup_longterm.c
> +++ b/tools/testing/selftests/mm/gup_longterm.c
> @@ -22,6 +22,9 @@
> #include <linux/memfd.h>
>
> #include "local_config.h"
> +#ifdef LOCAL_CONFIG_HAVE_LIBURING
> +#include <liburing.h>
> +#endif /* LOCAL_CONFIG_HAVE_LIBURING */
>
> #include "../../../../mm/gup_test.h"
> #include "../kselftest.h"
> @@ -80,6 +83,9 @@ enum test_type {
> TEST_TYPE_RO_FAST,
> TEST_TYPE_RW,
> TEST_TYPE_RW_FAST,
> +#ifdef LOCAL_CONFIG_HAVE_LIBURING
> + TEST_TYPE_IOURING,
> +#endif /* LOCAL_CONFIG_HAVE_LIBURING */
> };
>
> static void do_test(int fd, size_t size, enum test_type type, bool shared)
> @@ -173,6 +179,51 @@ static void do_test(int fd, size_t size, enum test_type type, bool shared)
> ksft_test_result(should_work, "Should have worked\n");
> break;
> }
> +#ifdef LOCAL_CONFIG_HAVE_LIBURING
> + case TEST_TYPE_IOURING: {
> + struct io_uring ring;
> + struct iovec iov;
> +
> + /* io_uring always pins pages writable. */
> + if (shared && fs_is_unknown(fs_type)) {
> + ksft_test_result_skip("Unknown filesystem\n");
> + return;
> + }
> + should_work = !shared ||
> + fs_supports_writable_longterm_pinning(fs_type);
> +
> + /* Skip on errors, as we might just lack kernel support. */
> + ret = io_uring_queue_init(1, &ring, 0);
> + if (ret < 0) {
> + ksft_test_result_skip("io_uring_queue_init() failed\n");
> + break;
> + }
> + /*
> + * Register the range as a fixed buffer. This will FOLL_WRITE |
> + * FOLL_PIN | FOLL_LONGTERM the range.
> + */
> + iov.iov_base = mem;
> + iov.iov_len = size;
> + ret = io_uring_register_buffers(&ring, &iov, 1);
> + /* Only new kernels return EFAULT. */
> + if (ret && (errno == ENOSPC || errno == EOPNOTSUPP ||
> + errno == EFAULT)) {
> + ksft_test_result(!should_work, "Should have failed\n");
> + } else if (ret) {
> + /*
> + * We might just lack support or have insufficient
> + * MEMLOCK limits.
> + */
> + ksft_test_result_skip("io_uring_register_buffers() failed\n");
> + } else {
> + ksft_test_result(should_work, "Should have worked\n");
> + io_uring_unregister_buffers(&ring);
> + }
> +
> + io_uring_queue_exit(&ring);
> + break;
> + }
> +#endif /* LOCAL_CONFIG_HAVE_LIBURING */
> default:
> assert(false);
> }
> @@ -310,6 +361,18 @@ static void test_private_ro_fast_pin(int fd, size_t size)
> do_test(fd, size, TEST_TYPE_RO_FAST, false);
> }
>
> +#ifdef LOCAL_CONFIG_HAVE_LIBURING
> +static void test_shared_iouring(int fd, size_t size)
> +{
> + do_test(fd, size, TEST_TYPE_IOURING, true);
> +}
> +
> +static void test_private_iouring(int fd, size_t size)
> +{
> + do_test(fd, size, TEST_TYPE_IOURING, false);
> +}
> +#endif /* LOCAL_CONFIG_HAVE_LIBURING */
> +
> static const struct test_case test_cases[] = {
> {
> "R/W longterm GUP pin in MAP_SHARED file mapping",
> @@ -343,6 +406,16 @@ static const struct test_case test_cases[] = {
> "R/O longterm GUP-fast pin in MAP_PRIVATE file mapping",
> test_private_ro_fast_pin,
> },
> +#ifdef LOCAL_CONFIG_HAVE_LIBURING
> + {
> + "io_uring fixed buffer with MAP_SHARED file mapping",
> + test_shared_iouring,
> + },
> + {
> + "io_uring fixed buffer with MAP_PRIVATE file mapping",
> + test_private_iouring,
> + },
> +#endif /* LOCAL_CONFIG_HAVE_LIBURING */
> };
>
> static void run_test_case(struct test_case const *test_case)
> --
> 2.40.1
>
All good,
Reviewed-by: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
