1 files changed, 127 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
new file mode 100644
index 000000000000..b8136d12a0f8
--- /dev/null
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <stdint.h>
+#include <stdbool.h>
+#include <sys/mman.h>
+#include <err.h>
+#include <stdarg.h>
+#include <strings.h> /* ffsl() */
+#include <unistd.h> /* _SC_PAGESIZE */
+#include "../kselftest.h"
+#include <linux/fs.h>
+
+#define BIT_ULL(nr)                   (1ULL << (nr))
+#define PM_SOFT_DIRTY                 BIT_ULL(55)
+#define PM_MMAP_EXCLUSIVE             BIT_ULL(56)
+#define PM_UFFD_WP                    BIT_ULL(57)
+#define PM_GUARD_REGION               BIT_ULL(58)
+#define PM_FILE                       BIT_ULL(61)
+#define PM_SWAP                       BIT_ULL(62)
+#define PM_PRESENT                    BIT_ULL(63)
+
+extern unsigned int __page_size;
+extern unsigned int __page_shift;
+
+/*
+ * Represents an open fd and PROCMAP_QUERY state for binary (via ioctl)
+ * /proc/$pid/[s]maps lookup.
+ */
+struct procmap_fd {
+	int fd;
+	struct procmap_query query;
+};
+
+static inline unsigned int psize(void)
+{
+	if (!__page_size)
+		__page_size = sysconf(_SC_PAGESIZE);
+	return __page_size;
+}
+
+static inline unsigned int pshift(void)
+{
+	if (!__page_shift)
+		__page_shift = (ffsl(psize()) - 1);
+	return __page_shift;
+}
+
+/*
+ * Plan 9 FS has bugs (at least on QEMU) where certain operations fail with
+ * ENOENT on unlinked files. See
+ * https://gitlab.com/qemu-project/qemu/-/issues/103 for some info about such
+ * bugs. There are rumours of NFS implementations with similar bugs.
+ *
+ * Ideally, tests should just detect filesystems known to have such issues and
+ * bail early. But 9pfs has the additional "feature" that it causes fstatfs to
+ * pass through the f_type field from the host filesystem. To avoid having to
+ * scrape /proc/mounts or some other hackery, tests can call this function when
+ * it seems such a bug might have been encountered.
+ */
+static inline void skip_test_dodgy_fs(const char *op_name)
+{
+	ksft_test_result_skip("%s failed with ENOENT. Filesystem might be buggy (9pfs?)\n", op_name);
+}
+
+uint64_t pagemap_get_entry(int fd, char *start);
+bool pagemap_is_softdirty(int fd, char *start);
+bool pagemap_is_swapped(int fd, char *start);
+bool pagemap_is_populated(int fd, char *start);
+unsigned long pagemap_get_pfn(int fd, char *start);
+void clear_softdirty(void);
+bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len);
+uint64_t read_pmd_pagesize(void);
+unsigned long rss_anon(void);
+bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size);
+bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size);
+bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size);
+int64_t allocate_transhuge(void *ptr, int pagemap_fd);
+unsigned long default_huge_page_size(void);
+int detect_hugetlb_page_sizes(size_t sizes[], int max);
+
+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_register_with_ioctls(int uffd, void *addr, uint64_t len,
+			      bool miss, bool wp, bool minor, uint64_t *ioctls);
+unsigned long get_free_hugepages(void);
+bool check_vmflag_io(void *addr);
+int open_procmap(pid_t pid, struct procmap_fd *procmap_out);
+int query_procmap(struct procmap_fd *procmap);
+bool find_vma_procmap(struct procmap_fd *procmap, void *address);
+int close_procmap(struct procmap_fd *procmap);
+int write_sysfs(const char *file_path, unsigned long val);
+int read_sysfs(const char *file_path, unsigned long *val);
+
+static inline int open_self_procmap(struct procmap_fd *procmap_out)
+{
+	pid_t pid = getpid();
+
+	return open_procmap(pid, procmap_out);
+}
+
+/* These helpers need to be inline to match the kselftest.h idiom. */
+static char test_name[1024];
+
+static inline void log_test_start(const char *name, ...)
+{
+	va_list args;
+	va_start(args, name);
+
+	vsnprintf(test_name, sizeof(test_name), name, args);
+	ksft_print_msg("[RUN] %s\n", test_name);
+
+	va_end(args);
+}
+
+static inline void log_test_result(int result)
+{
+	ksft_test_result_report(result, "%s\n", test_name);
+}
+
+/*
+ * On ppc64 this will only work with radix 2M hugepage size
+ */
+#define HPAGE_SHIFT 21
+#define HPAGE_SIZE (1 << HPAGE_SHIFT)
+
+#define PAGEMAP_PRESENT(ent)	(((ent) & (1ull << 63)) != 0)
+#define PAGEMAP_PFN(ent)	((ent) & ((1ull << 55) - 1))