+++ /dev/null
-#include <stdlib.h>
-#include <stdio.h>
-#include <sys/mman.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/types.h>
-
-typedef unsigned long long u64;
-
-#define PME_PRESENT (1ULL << 63)
-#define PME_SOFT_DIRTY (1Ull << 55)
-
-#define PAGES_TO_TEST 3
-#ifndef PAGE_SIZE
-#define PAGE_SIZE 4096
-#endif
-
-static void get_pagemap2(char *mem, u64 *map)
-{
- int fd;
-
- fd = open("/proc/self/pagemap2", O_RDONLY);
- if (fd < 0) {
- perror("Can't open pagemap2");
- exit(1);
- }
-
- lseek(fd, (unsigned long)mem / PAGE_SIZE * sizeof(u64), SEEK_SET);
- read(fd, map, sizeof(u64) * PAGES_TO_TEST);
- close(fd);
-}
-
-static inline char map_p(u64 map)
-{
- return map & PME_PRESENT ? 'p' : '-';
-}
-
-static inline char map_sd(u64 map)
-{
- return map & PME_SOFT_DIRTY ? 'd' : '-';
-}
-
-static int check_pte(int step, int page, u64 *map, u64 want)
-{
- if ((map[page] & want) != want) {
- printf("Step %d Page %d has %c%c, want %c%c\n",
- step, page,
- map_p(map[page]), map_sd(map[page]),
- map_p(want), map_sd(want));
- return 1;
- }
-
- return 0;
-}
-
-static void clear_refs(void)
-{
- int fd;
- char *v = "4";
-
- fd = open("/proc/self/clear_refs", O_WRONLY);
- if (write(fd, v, 3) < 3) {
- perror("Can't clear soft-dirty bit");
- exit(1);
- }
- close(fd);
-}
-
-int main(void)
-{
- char *mem, x;
- u64 map[PAGES_TO_TEST];
-
- mem = mmap(NULL, PAGES_TO_TEST * PAGE_SIZE,
- PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, 0, 0);
-
- x = mem[0];
- mem[2 * PAGE_SIZE] = 'c';
- get_pagemap2(mem, map);
-
- if (check_pte(1, 0, map, PME_PRESENT))
- return 1;
- if (check_pte(1, 1, map, 0))
- return 1;
- if (check_pte(1, 2, map, PME_PRESENT | PME_SOFT_DIRTY))
- return 1;
-
- clear_refs();
- get_pagemap2(mem, map);
-
- if (check_pte(2, 0, map, PME_PRESENT))
- return 1;
- if (check_pte(2, 1, map, 0))
- return 1;
- if (check_pte(2, 2, map, PME_PRESENT))
- return 1;
-
- mem[0] = 'a';
- mem[PAGE_SIZE] = 'b';
- x = mem[2 * PAGE_SIZE];
- get_pagemap2(mem, map);
-
- if (check_pte(3, 0, map, PME_PRESENT | PME_SOFT_DIRTY))
- return 1;
- if (check_pte(3, 1, map, PME_PRESENT | PME_SOFT_DIRTY))
- return 1;
- if (check_pte(3, 2, map, PME_PRESENT))
- return 1;
-
- (void)x; /* gcc warn */
-
- printf("PASS\n");
- return 0;
-}