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-rw-r--r--tools/testing/selftests/vm/mlock2-tests.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/tools/testing/selftests/vm/mlock2-tests.c b/tools/testing/selftests/vm/mlock2-tests.c
new file mode 100644
index 000000000..11b2301f3
--- /dev/null
+++ b/tools/testing/selftests/vm/mlock2-tests.c
@@ -0,0 +1,520 @@
+// 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 "mlock2.h"
+
+#include "../kselftest.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};
+ char *end_addr;
+ char *stop;
+ 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)) {
+ end_addr = strchr(line, '-');
+ if (!end_addr) {
+ printf("cannot parse /proc/self/maps\n");
+ goto out;
+ }
+ *end_addr = '\0';
+ end_addr++;
+ stop = strchr(end_addr, ' ');
+ if (!stop) {
+ printf("cannot parse /proc/self/maps\n");
+ goto out;
+ }
+ stop = '\0';
+
+ sscanf(line, "%lx", &start);
+ sscanf(end_addr, "%lx", &end);
+
+ 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) {
+ printf("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) {
+ printf("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) {
+ printf("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)) {
+ printf("VMA flag %s is present on page 1 after unlock\n", LOCKED);
+ return 1;
+ }
+
+ return 0;
+}
+
+static int test_mlock_lock()
+{
+ char *map;
+ int ret = 1;
+ 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) {
+ perror("test_mlock_locked mmap");
+ goto out;
+ }
+
+ if (mlock2_(map, 2 * page_size, 0)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock2(0)");
+ goto unmap;
+ }
+
+ if (!lock_check((unsigned long)map))
+ goto unmap;
+
+ /* Now unlock and recheck attributes */
+ if (munlock(map, 2 * page_size)) {
+ perror("munlock()");
+ goto unmap;
+ }
+
+ ret = unlock_lock_check(map);
+
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ return ret;
+}
+
+static int onfault_check(char *map)
+{
+ *map = 'a';
+ if (!is_vma_lock_on_fault((unsigned long)map)) {
+ printf("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)) {
+ printf("VMA is still lock on fault after unlock\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+static int test_mlock_onfault()
+{
+ char *map;
+ int ret = 1;
+ 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) {
+ perror("test_mlock_locked mmap");
+ goto out;
+ }
+
+ if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock2(MLOCK_ONFAULT)");
+ goto unmap;
+ }
+
+ if (onfault_check(map))
+ goto unmap;
+
+ /* Now unlock and recheck attributes */
+ if (munlock(map, 2 * page_size)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("munlock()");
+ goto unmap;
+ }
+
+ ret = unlock_onfault_check(map);
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ return ret;
+}
+
+static int test_lock_onfault_of_present()
+{
+ char *map;
+ int ret = 1;
+ 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) {
+ perror("test_mlock_locked mmap");
+ goto out;
+ }
+
+ *map = 'a';
+
+ if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock2(MLOCK_ONFAULT)");
+ goto unmap;
+ }
+
+ if (!is_vma_lock_on_fault((unsigned long)map) ||
+ !is_vma_lock_on_fault((unsigned long)map + page_size)) {
+ printf("VMA with present pages is not marked lock on fault\n");
+ goto unmap;
+ }
+ ret = 0;
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ return ret;
+}
+
+static int test_munlockall()
+{
+ char *map;
+ int ret = 1;
+ 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) {
+ perror("test_munlockall mmap");
+ goto out;
+ }
+
+ if (mlockall(MCL_CURRENT)) {
+ perror("mlockall(MCL_CURRENT)");
+ goto out;
+ }
+
+ if (!lock_check((unsigned long)map))
+ goto unmap;
+
+ if (munlockall()) {
+ perror("munlockall()");
+ goto unmap;
+ }
+
+ if (unlock_lock_check(map))
+ goto unmap;
+
+ munmap(map, 2 * page_size);
+
+ map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+
+ if (map == MAP_FAILED) {
+ perror("test_munlockall second mmap");
+ goto out;
+ }
+
+ if (mlockall(MCL_CURRENT | MCL_ONFAULT)) {
+ perror("mlockall(MCL_CURRENT | MCL_ONFAULT)");
+ goto unmap;
+ }
+
+ if (onfault_check(map))
+ goto unmap;
+
+ if (munlockall()) {
+ perror("munlockall()");
+ goto unmap;
+ }
+
+ if (unlock_onfault_check(map))
+ goto unmap;
+
+ if (mlockall(MCL_CURRENT | MCL_FUTURE)) {
+ perror("mlockall(MCL_CURRENT | MCL_FUTURE)");
+ goto out;
+ }
+
+ if (!lock_check((unsigned long)map))
+ goto unmap;
+
+ if (munlockall()) {
+ perror("munlockall()");
+ goto unmap;
+ }
+
+ ret = unlock_lock_check(map);
+
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ munlockall();
+ return ret;
+}
+
+static int test_vma_management(bool call_mlock)
+{
+ int ret = 1;
+ 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) {
+ perror("mmap()");
+ return ret;
+ }
+
+ if (call_mlock && mlock2_(map, 3 * page_size, MLOCK_ONFAULT)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock(ONFAULT)\n");
+ goto out;
+ }
+
+ 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)) {
+ printf("couldn't find mapping in /proc/self/maps\n");
+ goto out;
+ }
+
+ /*
+ * 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) {
+ printf("VMAs are not merged to start, aborting test\n");
+ ret = 0;
+ goto out;
+ }
+
+ if (munlock(map + page_size, page_size)) {
+ perror("munlock()");
+ goto out;
+ }
+
+ 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)) {
+ printf("couldn't find mapping in /proc/self/maps\n");
+ goto out;
+ }
+
+ /* All three VMAs should be different */
+ if (page1.start == page2.start || page2.start == page3.start) {
+ printf("failed to split VMA for munlock\n");
+ goto out;
+ }
+
+ /* Now unlock the first and third page and check the VMAs again */
+ if (munlock(map, page_size * 3)) {
+ perror("munlock()");
+ goto out;
+ }
+
+ 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)) {
+ printf("couldn't find mapping in /proc/self/maps\n");
+ goto out;
+ }
+
+ /* Now all three VMAs should be the same */
+ if (page1.start != page2.start || page2.start != page3.start) {
+ printf("failed to merge VMAs after munlock\n");
+ goto out;
+ }
+
+ ret = 0;
+out:
+ munmap(map, 3 * page_size);
+ return ret;
+}
+
+static int test_mlockall(int (test_function)(bool call_mlock))
+{
+ int ret = 1;
+
+ if (mlockall(MCL_CURRENT | MCL_ONFAULT | MCL_FUTURE)) {
+ perror("mlockall");
+ return ret;
+ }
+
+ ret = test_function(false);
+ munlockall();
+ return ret;
+}
+
+int main(int argc, char **argv)
+{
+ int ret = 0;
+ ret += test_mlock_lock();
+ ret += test_mlock_onfault();
+ ret += test_munlockall();
+ ret += test_lock_onfault_of_present();
+ ret += test_vma_management(true);
+ ret += test_mlockall(test_vma_management);
+ return ret;
+}