On 6/6/23 12:16 PM, John Hubbard wrote:
> 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.
>
> Cc: Peter Xu <peterx@xxxxxxxxxx>
> Acked-by: David Hildenbrand <david@xxxxxxxxxx>
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
Tested-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
> ---
> tools/testing/selftests/mm/uffd-common.c | 59 ++++++++++++++++++++++++
> tools/testing/selftests/mm/uffd-common.h | 5 ++
> tools/testing/selftests/mm/vm_util.c | 59 ------------------------
> tools/testing/selftests/mm/vm_util.h | 4 --
> 4 files changed, 64 insertions(+), 63 deletions(-)
>
> 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;
> +}
> diff --git a/tools/testing/selftests/mm/uffd-common.h b/tools/testing/selftests/mm/uffd-common.h
> index 6068f2346b86..197f5262fe0d 100644
> --- a/tools/testing/selftests/mm/uffd-common.h
> +++ b/tools/testing/selftests/mm/uffd-common.h
> @@ -110,6 +110,11 @@ int __copy_page(int ufd, unsigned long offset, bool retry, bool wp);
> int copy_page(int ufd, unsigned long offset, bool wp);
> void *uffd_poll_thread(void *arg);
>
> +int uffd_open_dev(unsigned int flags);
> +int uffd_open_sys(unsigned int flags);
> +int uffd_open(unsigned int flags);
> +int uffd_get_features(uint64_t *features);
> +
> #define TEST_ANON 1
> #define TEST_HUGETLB 2
> #define TEST_SHMEM 3
> diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
> index 9b06a5034808..681277615839 100644
> --- a/tools/testing/selftests/mm/vm_util.c
> +++ b/tools/testing/selftests/mm/vm_util.c
> @@ -242,62 +242,3 @@ int uffd_unregister(int uffd, void *addr, uint64_t len)
>
> return ret;
> }
> -
> -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;
> -}
> diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
> index 07f39ed2efba..c2d4ff798b91 100644
> --- a/tools/testing/selftests/mm/vm_util.h
> +++ b/tools/testing/selftests/mm/vm_util.h
> @@ -48,10 +48,6 @@ unsigned long default_huge_page_size(void);
> int uffd_register(int uffd, void *addr, uint64_t len,
> bool miss, bool wp, bool minor);
> int uffd_unregister(int uffd, void *addr, uint64_t len);
> -int uffd_open_dev(unsigned int flags);
> -int uffd_open_sys(unsigned int flags);
> -int uffd_open(unsigned int flags);
> -int uffd_get_features(uint64_t *features);
> int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len,
> bool miss, bool wp, bool minor, uint64_t *ioctls);
>
--
BR,
Muhammad Usama Anjum
