From 56d2afff13834020b91a81220684be946a4e1ef3 Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Tue, 6 Jun 2023 00:16:35 -0700 Subject: selftests/mm: move certain uffd*() routines from vm_util.c to uffd-common.c There are only three uffd*() routines that are used outside of the uffd selftests. Leave these in vm_util.c, where they are available to any mm selftest program: uffd_register() uffd_unregister() uffd_register_with_ioctls(). A few other uffd*() routines, however, are only used by the uffd-focused tests found in uffd-stress.c and uffd-unit-tests.c. Move those routines into uffd-common.c. Link: https://lkml.kernel.org/r/20230606071637.267103-10-jhubbard@nvidia.com Signed-off-by: John Hubbard Acked-by: David Hildenbrand Tested-by: Muhammad Usama Anjum Cc: Peter Xu Cc: Jonathan Corbet Cc: Nathan Chancellor Cc: Shuah Khan Signed-off-by: Andrew Morton --- tools/testing/selftests/mm/uffd-common.c | 59 ++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) (limited to 'tools/testing/selftests/mm/uffd-common.c') diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c index 61c6250adf93..ba20d7504022 100644 --- a/tools/testing/selftests/mm/uffd-common.c +++ b/tools/testing/selftests/mm/uffd-common.c @@ -616,3 +616,62 @@ int copy_page(int ufd, unsigned long offset, bool wp) { return __copy_page(ufd, offset, false, wp); } + +int uffd_open_dev(unsigned int flags) +{ + int fd, uffd; + + fd = open("/dev/userfaultfd", O_RDWR | O_CLOEXEC); + if (fd < 0) + return fd; + uffd = ioctl(fd, USERFAULTFD_IOC_NEW, flags); + close(fd); + + return uffd; +} + +int uffd_open_sys(unsigned int flags) +{ +#ifdef __NR_userfaultfd + return syscall(__NR_userfaultfd, flags); +#else + return -1; +#endif +} + +int uffd_open(unsigned int flags) +{ + int uffd = uffd_open_sys(flags); + + if (uffd < 0) + uffd = uffd_open_dev(flags); + + return uffd; +} + +int uffd_get_features(uint64_t *features) +{ + struct uffdio_api uffdio_api = { .api = UFFD_API, .features = 0 }; + /* + * This should by default work in most kernels; the feature list + * will be the same no matter what we pass in here. + */ + int fd = uffd_open(UFFD_USER_MODE_ONLY); + + if (fd < 0) + /* Maybe the kernel is older than user-only mode? */ + fd = uffd_open(0); + + if (fd < 0) + return fd; + + if (ioctl(fd, UFFDIO_API, &uffdio_api)) { + close(fd); + return -errno; + } + + *features = uffdio_api.features; + close(fd); + + return 0; +} -- cgit v1.2.3