// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <sys/mman.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <stdbool.h>
#include "../kselftest.h"
#include "mlock2.h"
struct vm_boundaries {
unsigned long start;
unsigned long end;
};
static int get_vm_area(unsigned long addr, struct vm_boundaries *area)
{
FILE *file;
int ret = 1;
char line[1024] = {0};
unsigned long start;
unsigned long end;
if (!area)
return ret;
file = fopen("/proc/self/maps", "r");
if (!file) {
perror("fopen");
return ret;
}
memset(area, 0, sizeof(struct vm_boundaries));
while(fgets(line, 1024, file)) {
if (sscanf(line, "%lx-%lx", &start, &end) != 2) {
ksft_print_msg("cannot parse /proc/self/maps\n");
goto out;
}
if (start <= addr && end > addr) {
area->start = start;
area->end = end;
ret = 0;
goto out;
}
}
out:
fclose(file);
return ret;
}
#define VMFLAGS "VmFlags:"
static bool is_vmflag_set(unsigned long addr, const char *vmflag)
{
char *line = NULL;
char *flags;
size_t size = 0;
bool ret = false;
FILE *smaps;
smaps = seek_to_smaps_entry(addr);
if (!smaps) {
ksft_print_msg("Unable to parse /proc/self/smaps\n");
goto out;
}
while (getline(&line, &size, smaps) > 0) {
if (!strstr(line, VMFLAGS)) {
free(line);
line = NULL;
size = 0;
continue;
}
flags = line + strlen(VMFLAGS);
ret = (strstr(flags, vmflag) != NULL);
goto out;
}
out:
free(line);
fclose(smaps);
return ret;
}
#define SIZE "Size:"
#define RSS "Rss:"
#define LOCKED "lo"
static unsigned long get_value_for_name(unsigned long addr, const char *name)
{
char *line = NULL;
size_t size = 0;
char *value_ptr;
FILE *smaps = NULL;
unsigned long value = -1UL;
smaps = seek_to_smaps_entry(addr);
if (!smaps) {
ksft_print_msg("Unable to parse /proc/self/smaps\n");
goto out;
}
while (getline(&line, &size, smaps) > 0) {
if (!strstr(line, name)) {
free(line);
line = NULL;
size = 0;
continue;
}
value_ptr = line + strlen(name);
if (sscanf(value_ptr, "%lu kB", &value) < 1) {
ksft_print_msg("Unable to parse smaps entry for Size\n");
goto out;
}
break;
}
out:
if (smaps)
fclose(smaps);
free(line);
return value;
}
static bool is_vma_lock_on_fault(unsigned long addr)
{
bool locked;
unsigned long vma_size, vma_rss;
locked = is_vmflag_set(addr, LOCKED);
if (!locked)
return false;
vma_size = get_value_for_name(addr, SIZE);
vma_rss = get_value_for_name(addr, RSS);
/* only one page is faulted in */
return (vma_rss < vma_size);
}
#define PRESENT_BIT 0x8000000000000000ULL
#define PFN_MASK 0x007FFFFFFFFFFFFFULL
#define UNEVICTABLE_BIT (1UL << 18)
static int lock_check(unsigned long addr)
{
bool locked;
unsigned long vma_size, vma_rss;
locked = is_vmflag_set(addr, LOCKED);
if (!locked)
return false;
vma_size = get_value_for_name(addr, SIZE);
vma_rss = get_value_for_name(addr, RSS);
return (vma_rss == vma_size);
}
static int unlock_lock_check(char *map)
{
if (is_vmflag_set((unsigned long)map, LOCKED)) {
ksft_print_msg("VMA flag %s is present on page 1 after unlock\n", LOCKED);
return 1;
}
return 0;
}
static void test_mlock_lock(void)
{
char *map;
unsigned long page_size = getpagesize();
map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (map == MAP_FAILED)
ksft_exit_fail_msg("mmap error: %s", strerror(errno));
if (mlock2_(map, 2 * page_size, 0)) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("mlock2(0): %s\n", strerror(errno));
}
ksft_test_result(lock_check((unsigned long)map), "%s: Locked\n", __func__);
/* Now unlock and recheck attributes */
if (munlock(map, 2 * page_size)) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("munlock(): %s\n", strerror(errno));
}
ksft_test_result(!unlock_lock_check(map), "%s: Locked\n", __func__);
munmap(map, 2 * page_size);
}
static int onfault_check(char *map)
{
*map = 'a';
if (!is_vma_lock_on_fault((unsigned long)map)) {
ksft_print_msg("VMA is not marked for lock on fault\n");
return 1;
}
return 0;
}
static int unlock_onfault_check(char *map)
{
unsigned long page_size = getpagesize();
if (is_vma_lock_on_fault((unsigned long)map) ||
is_vma_lock_on_fault((unsigned long)map + page_size)) {
ksft_print_msg("VMA is still lock on fault after unlock\n");
return 1;
}
return 0;
}
static void test_mlock_onfault(void)
{
char *map;
unsigned long page_size = getpagesize();
map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (map == MAP_FAILED)
ksft_exit_fail_msg("mmap error: %s", strerror(errno));
if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("mlock2(MLOCK_ONFAULT): %s\n", strerror(errno));
}
ksft_test_result(!onfault_check(map), "%s: VMA marked for lock on fault\n", __func__);
/* Now unlock and recheck attributes */
if (munlock(map, 2 * page_size)) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("munlock(): %s\n", strerror(errno));
}
ksft_test_result(!unlock_onfault_check(map), "VMA open lock after fault\n");
munmap(map, 2 * page_size);
}
static void test_lock_onfault_of_present(void)
{
char *map;
unsigned long page_size = getpagesize();
map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (map == MAP_FAILED)
ksft_exit_fail_msg("mmap error: %s", strerror(errno));
*map = 'a';
if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {
munmap(map, 2 * page_size);
ksft_test_result_fail("mlock2(MLOCK_ONFAULT) error: %s", strerror(errno));
}
ksft_test_result(is_vma_lock_on_fault((unsigned long)map) ||
is_vma_lock_on_fault((unsigned long)map + page_size),
"VMA with present pages is not marked lock on fault\n");
munmap(map, 2 * page_size);
}
static void test_munlockall0(void)
{
char *map;
unsigned long page_size = getpagesize();
map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (map == MAP_FAILED)
ksft_exit_fail_msg("mmap error: %s\n", strerror(errno));
if (mlockall(MCL_CURRENT)) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("mlockall(MCL_CURRENT): %s\n", strerror(errno));
}
ksft_test_result(lock_check((unsigned long)map), "%s: Locked memory area\n", __func__);
if (munlockall()) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("munlockall(): %s\n", strerror(errno));
}
ksft_test_result(!unlock_lock_check(map), "%s: No locked memory\n", __func__);
munmap(map, 2 * page_size);
}
static void test_munlockall1(void)
{
char *map;
unsigned long page_size = getpagesize();
map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (map == MAP_FAILED)
ksft_exit_fail_msg("mmap error: %s", strerror(errno));
if (mlockall(MCL_CURRENT | MCL_ONFAULT)) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("mlockall(MCL_CURRENT | MCL_ONFAULT): %s\n", strerror(errno));
}
ksft_test_result(!onfault_check(map), "%s: VMA marked for lock on fault\n", __func__);
if (munlockall()) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("munlockall(): %s\n", strerror(errno));
}
ksft_test_result(!unlock_onfault_check(map), "%s: Unlocked\n", __func__);
if (mlockall(MCL_CURRENT | MCL_FUTURE)) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("mlockall(MCL_CURRENT | MCL_FUTURE): %s\n", strerror(errno));
}
ksft_test_result(lock_check((unsigned long)map), "%s: Locked\n", __func__);
if (munlockall()) {
munmap(map, 2 * page_size);
ksft_exit_fail_msg("munlockall() %s\n", strerror(errno));
}
ksft_test_result(!unlock_lock_check(map), "%s: No locked memory\n", __func__);
munmap(map, 2 * page_size);
}
static void test_vma_management(bool call_mlock)
{
void *map;
unsigned long page_size = getpagesize();
struct vm_boundaries page1;
struct vm_boundaries page2;
struct vm_boundaries page3;
map = mmap(NULL, 3 * page_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (map == MAP_FAILED)
ksft_exit_fail_msg("mmap error: %s", strerror(errno));
if (call_mlock && mlock2_(map, 3 * page_size, MLOCK_ONFAULT)) {
munmap(map, 3 * page_size);
ksft_test_result_fail("mlock error: %s", strerror(errno));
}
if (get_vm_area((unsigned long)map, &page1) ||
get_vm_area((unsigned long)map + page_size, &page2) ||
get_vm_area((unsigned long)map + page_size * 2, &page3)) {
munmap(map, 3 * page_size);
ksft_test_result_fail("couldn't find mapping in /proc/self/maps");
}
/*
* Before we unlock a portion, we need to that all three pages are in
* the same VMA. If they are not we abort this test (Note that this is
* not a failure)
*/
if (page1.start != page2.start || page2.start != page3.start) {
munmap(map, 3 * page_size);
ksft_test_result_fail("VMAs are not merged to start, aborting test");
}
if (munlock(map + page_size, page_size)) {
munmap(map, 3 * page_size);
ksft_test_result_fail("munlock(): %s", strerror(errno));
}
if (get_vm_area((unsigned long)map, &page1) ||
get_vm_area((unsigned long)map + page_size, &page2) ||
get_vm_area((unsigned long)map + page_size * 2, &page3)) {
munmap(map, 3 * page_size);
ksft_test_result_fail("couldn't find mapping in /proc/self/maps");
}
/* All three VMAs should be different */
if (page1.start == page2.start || page2.start == page3.start) {
munmap(map, 3 * page_size);
ksft_test_result_fail("failed to split VMA for munlock");
}
/* Now unlock the first and third page and check the VMAs again */
if (munlock(map, page_size * 3)) {
munmap(map, 3 * page_size);
ksft_test_result_fail("munlock(): %s", strerror(errno));
}
if (get_vm_area((unsigned long)map, &page1) ||
get_vm_area((unsigned long)map + page_size, &page2) ||
get_vm_area((unsigned long)map + page_size * 2, &page3)) {
munmap(map, 3 * page_size);
ksft_test_result_fail("couldn't find mapping in /proc/self/maps");
}
/* Now all three VMAs should be the same */
if (page1.start != page2.start || page2.start != page3.start) {
munmap(map, 3 * page_size);
ksft_test_result_fail("failed to merge VMAs after munlock");
}
ksft_test_result_pass("%s call_mlock %d\n", __func__, call_mlock);
munmap(map, 3 * page_size);
}
static void test_mlockall(void)
{
if (mlockall(MCL_CURRENT | MCL_ONFAULT | MCL_FUTURE))
ksft_exit_fail_msg("mlockall failed: %s\n", strerror(errno));
test_vma_management(false);
munlockall();
}
int main(int argc, char **argv)
{
int ret, size = 3 * getpagesize();
void *map;
ksft_print_header();
map = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (map == MAP_FAILED)
ksft_exit_fail_msg("mmap error: %s", strerror(errno));
ret = mlock2_(map, size, MLOCK_ONFAULT);
if (ret && errno == ENOSYS)
ksft_finished();
munmap(map, size);
ksft_set_plan(13);
test_mlock_lock();
test_mlock_onfault();
test_munlockall0();
test_munlockall1();
test_lock_onfault_of_present();
test_vma_management(true);
test_mlockall();
ksft_finished();
}
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