aboutsummaryrefslogtreecommitdiffstats
path: root/tools/testing/selftests/vm/userfaultfd.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/testing/selftests/vm/userfaultfd.c')
-rw-r--r--tools/testing/selftests/vm/userfaultfd.c484
1 files changed, 441 insertions, 43 deletions
diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c
index d77ed41b2094..e9449c801888 100644
--- a/tools/testing/selftests/vm/userfaultfd.c
+++ b/tools/testing/selftests/vm/userfaultfd.c
@@ -63,6 +63,7 @@
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>
+#include <sys/wait.h>
#include <pthread.h>
#include <linux/userfaultfd.h>
@@ -76,8 +77,12 @@ static unsigned long nr_cpus, nr_pages, nr_pages_per_cpu, page_size;
#define BOUNCE_POLL (1<<3)
static int bounces;
+#ifdef HUGETLB_TEST
+static int huge_fd;
+static char *huge_fd_off0;
+#endif
static unsigned long long *count_verify;
-static int uffd, finished, *pipefd;
+static int uffd, uffd_flags, finished, *pipefd;
static char *area_src, *area_dst;
static char *zeropage;
pthread_attr_t attr;
@@ -97,6 +102,102 @@ pthread_attr_t attr;
~(unsigned long)(sizeof(unsigned long long) \
- 1)))
+#if !defined(HUGETLB_TEST) && !defined(SHMEM_TEST)
+
+/* Anonymous memory */
+#define EXPECTED_IOCTLS ((1 << _UFFDIO_WAKE) | \
+ (1 << _UFFDIO_COPY) | \
+ (1 << _UFFDIO_ZEROPAGE))
+
+static int release_pages(char *rel_area)
+{
+ int ret = 0;
+
+ if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED)) {
+ perror("madvise");
+ ret = 1;
+ }
+
+ return ret;
+}
+
+static void allocate_area(void **alloc_area)
+{
+ if (posix_memalign(alloc_area, page_size, nr_pages * page_size)) {
+ fprintf(stderr, "out of memory\n");
+ *alloc_area = NULL;
+ }
+}
+
+#else /* HUGETLB_TEST or SHMEM_TEST */
+
+#define EXPECTED_IOCTLS UFFD_API_RANGE_IOCTLS_BASIC
+
+#ifdef HUGETLB_TEST
+
+/* HugeTLB memory */
+static int release_pages(char *rel_area)
+{
+ int ret = 0;
+
+ if (fallocate(huge_fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ rel_area == huge_fd_off0 ? 0 :
+ nr_pages * page_size,
+ nr_pages * page_size)) {
+ perror("fallocate");
+ ret = 1;
+ }
+
+ return ret;
+}
+
+
+static void allocate_area(void **alloc_area)
+{
+ *alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_HUGETLB, huge_fd,
+ *alloc_area == area_src ? 0 :
+ nr_pages * page_size);
+ if (*alloc_area == MAP_FAILED) {
+ fprintf(stderr, "mmap of hugetlbfs file failed\n");
+ *alloc_area = NULL;
+ }
+
+ if (*alloc_area == area_src)
+ huge_fd_off0 = *alloc_area;
+}
+
+#elif defined(SHMEM_TEST)
+
+/* Shared memory */
+static int release_pages(char *rel_area)
+{
+ int ret = 0;
+
+ if (madvise(rel_area, nr_pages * page_size, MADV_REMOVE)) {
+ perror("madvise");
+ ret = 1;
+ }
+
+ return ret;
+}
+
+static void allocate_area(void **alloc_area)
+{
+ *alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_SHARED, -1, 0);
+ if (*alloc_area == MAP_FAILED) {
+ fprintf(stderr, "shared memory mmap failed\n");
+ *alloc_area = NULL;
+ }
+}
+
+#else /* SHMEM_TEST */
+#error "Undefined test type"
+#endif /* HUGETLB_TEST */
+
+#endif /* !defined(HUGETLB_TEST) && !defined(SHMEM_TEST) */
+
static int my_bcmp(char *str1, char *str2, size_t n)
{
unsigned long i;
@@ -217,7 +318,7 @@ static void *locking_thread(void *arg)
return NULL;
}
-static int copy_page(unsigned long offset)
+static int copy_page(int ufd, unsigned long offset)
{
struct uffdio_copy uffdio_copy;
@@ -229,7 +330,7 @@ static int copy_page(unsigned long offset)
uffdio_copy.len = page_size;
uffdio_copy.mode = 0;
uffdio_copy.copy = 0;
- if (ioctl(uffd, UFFDIO_COPY, &uffdio_copy)) {
+ if (ioctl(ufd, UFFDIO_COPY, &uffdio_copy)) {
/* real retval in ufdio_copy.copy */
if (uffdio_copy.copy != -EEXIST)
fprintf(stderr, "UFFDIO_COPY error %Ld\n",
@@ -247,6 +348,7 @@ static void *uffd_poll_thread(void *arg)
unsigned long cpu = (unsigned long) arg;
struct pollfd pollfd[2];
struct uffd_msg msg;
+ struct uffdio_register uffd_reg;
int ret;
unsigned long offset;
char tmp_chr;
@@ -278,16 +380,35 @@ static void *uffd_poll_thread(void *arg)
continue;
perror("nonblocking read error"), exit(1);
}
- if (msg.event != UFFD_EVENT_PAGEFAULT)
+ switch (msg.event) {
+ default:
fprintf(stderr, "unexpected msg event %u\n",
msg.event), exit(1);
- if (msg.arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE)
- fprintf(stderr, "unexpected write fault\n"), exit(1);
- offset = (char *)(unsigned long)msg.arg.pagefault.address -
- area_dst;
- offset &= ~(page_size-1);
- if (copy_page(offset))
- userfaults++;
+ break;
+ case UFFD_EVENT_PAGEFAULT:
+ if (msg.arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE)
+ fprintf(stderr, "unexpected write fault\n"), exit(1);
+ offset = (char *)(unsigned long)msg.arg.pagefault.address -
+ area_dst;
+ offset &= ~(page_size-1);
+ if (copy_page(uffd, offset))
+ userfaults++;
+ break;
+ case UFFD_EVENT_FORK:
+ uffd = msg.arg.fork.ufd;
+ pollfd[0].fd = uffd;
+ break;
+ case UFFD_EVENT_REMOVE:
+ uffd_reg.range.start = msg.arg.remove.start;
+ uffd_reg.range.len = msg.arg.remove.end -
+ msg.arg.remove.start;
+ if (ioctl(uffd, UFFDIO_UNREGISTER, &uffd_reg.range))
+ fprintf(stderr, "remove failure\n"), exit(1);
+ break;
+ case UFFD_EVENT_REMAP:
+ area_dst = (char *)(unsigned long)msg.arg.remap.to;
+ break;
+ }
}
return (void *)userfaults;
}
@@ -324,7 +445,7 @@ static void *uffd_read_thread(void *arg)
offset = (char *)(unsigned long)msg.arg.pagefault.address -
area_dst;
offset &= ~(page_size-1);
- if (copy_page(offset))
+ if (copy_page(uffd, offset))
(*this_cpu_userfaults)++;
}
return (void *)NULL;
@@ -338,7 +459,7 @@ static void *background_thread(void *arg)
for (page_nr = cpu * nr_pages_per_cpu;
page_nr < (cpu+1) * nr_pages_per_cpu;
page_nr++)
- copy_page(page_nr * page_size);
+ copy_page(uffd, page_nr * page_size);
return NULL;
}
@@ -384,10 +505,8 @@ static int stress(unsigned long *userfaults)
* UFFDIO_COPY without writing zero pages into area_dst
* because the background threads already completed).
*/
- if (madvise(area_src, nr_pages * page_size, MADV_DONTNEED)) {
- perror("madvise");
+ if (release_pages(area_src))
return 1;
- }
for (cpu = 0; cpu < nr_cpus; cpu++) {
char c;
@@ -414,27 +533,9 @@ static int stress(unsigned long *userfaults)
return 0;
}
-static int userfaultfd_stress(void)
+static int userfaultfd_open(int features)
{
- void *area;
- char *tmp_area;
- unsigned long nr;
- struct uffdio_register uffdio_register;
struct uffdio_api uffdio_api;
- unsigned long cpu;
- int uffd_flags, err;
- unsigned long userfaults[nr_cpus];
-
- if (posix_memalign(&area, page_size, nr_pages * page_size)) {
- fprintf(stderr, "out of memory\n");
- return 1;
- }
- area_src = area;
- if (posix_memalign(&area, page_size, nr_pages * page_size)) {
- fprintf(stderr, "out of memory\n");
- return 1;
- }
- area_dst = area;
uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
if (uffd < 0) {
@@ -445,7 +546,7 @@ static int userfaultfd_stress(void)
uffd_flags = fcntl(uffd, F_GETFD, NULL);
uffdio_api.api = UFFD_API;
- uffdio_api.features = 0;
+ uffdio_api.features = features;
if (ioctl(uffd, UFFDIO_API, &uffdio_api)) {
fprintf(stderr, "UFFDIO_API\n");
return 1;
@@ -455,6 +556,233 @@ static int userfaultfd_stress(void)
return 1;
}
+ return 0;
+}
+
+/*
+ * For non-cooperative userfaultfd test we fork() a process that will
+ * generate pagefaults, will mremap the area monitored by the
+ * userfaultfd and at last this process will release the monitored
+ * area.
+ * For the anonymous and shared memory the area is divided into two
+ * parts, the first part is accessed before mremap, and the second
+ * part is accessed after mremap. Since hugetlbfs does not support
+ * mremap, the entire monitored area is accessed in a single pass for
+ * HUGETLB_TEST.
+ * The release of the pages currently generates event for shmem and
+ * anonymous memory (UFFD_EVENT_REMOVE), hence it is not checked
+ * for hugetlb.
+ */
+static int faulting_process(void)
+{
+ unsigned long nr;
+ unsigned long long count;
+
+#ifndef HUGETLB_TEST
+ unsigned long split_nr_pages = (nr_pages + 1) / 2;
+#else
+ unsigned long split_nr_pages = nr_pages;
+#endif
+
+ for (nr = 0; nr < split_nr_pages; nr++) {
+ count = *area_count(area_dst, nr);
+ if (count != count_verify[nr]) {
+ fprintf(stderr,
+ "nr %lu memory corruption %Lu %Lu\n",
+ nr, count,
+ count_verify[nr]), exit(1);
+ }
+ }
+
+#ifndef HUGETLB_TEST
+ area_dst = mremap(area_dst, nr_pages * page_size, nr_pages * page_size,
+ MREMAP_MAYMOVE | MREMAP_FIXED, area_src);
+ if (area_dst == MAP_FAILED)
+ perror("mremap"), exit(1);
+
+ for (; nr < nr_pages; nr++) {
+ count = *area_count(area_dst, nr);
+ if (count != count_verify[nr]) {
+ fprintf(stderr,
+ "nr %lu memory corruption %Lu %Lu\n",
+ nr, count,
+ count_verify[nr]), exit(1);
+ }
+ }
+
+ if (release_pages(area_dst))
+ return 1;
+
+ for (nr = 0; nr < nr_pages; nr++) {
+ if (my_bcmp(area_dst + nr * page_size, zeropage, page_size))
+ fprintf(stderr, "nr %lu is not zero\n", nr), exit(1);
+ }
+
+#endif /* HUGETLB_TEST */
+
+ return 0;
+}
+
+static int uffdio_zeropage(int ufd, unsigned long offset)
+{
+ struct uffdio_zeropage uffdio_zeropage;
+ int ret;
+ unsigned long has_zeropage = EXPECTED_IOCTLS & (1 << _UFFDIO_ZEROPAGE);
+
+ if (offset >= nr_pages * page_size)
+ fprintf(stderr, "unexpected offset %lu\n",
+ offset), exit(1);
+ uffdio_zeropage.range.start = (unsigned long) area_dst + offset;
+ uffdio_zeropage.range.len = page_size;
+ uffdio_zeropage.mode = 0;
+ ret = ioctl(ufd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
+ if (ret) {
+ /* real retval in ufdio_zeropage.zeropage */
+ if (has_zeropage) {
+ if (uffdio_zeropage.zeropage == -EEXIST)
+ fprintf(stderr, "UFFDIO_ZEROPAGE -EEXIST\n"),
+ exit(1);
+ else
+ fprintf(stderr, "UFFDIO_ZEROPAGE error %Ld\n",
+ uffdio_zeropage.zeropage), exit(1);
+ } else {
+ if (uffdio_zeropage.zeropage != -EINVAL)
+ fprintf(stderr,
+ "UFFDIO_ZEROPAGE not -EINVAL %Ld\n",
+ uffdio_zeropage.zeropage), exit(1);
+ }
+ } else if (has_zeropage) {
+ if (uffdio_zeropage.zeropage != page_size) {
+ fprintf(stderr, "UFFDIO_ZEROPAGE unexpected %Ld\n",
+ uffdio_zeropage.zeropage), exit(1);
+ } else
+ return 1;
+ } else {
+ fprintf(stderr,
+ "UFFDIO_ZEROPAGE succeeded %Ld\n",
+ uffdio_zeropage.zeropage), exit(1);
+ }
+
+ return 0;
+}
+
+/* exercise UFFDIO_ZEROPAGE */
+static int userfaultfd_zeropage_test(void)
+{
+ struct uffdio_register uffdio_register;
+ unsigned long expected_ioctls;
+
+ printf("testing UFFDIO_ZEROPAGE: ");
+ fflush(stdout);
+
+ if (release_pages(area_dst))
+ return 1;
+
+ if (userfaultfd_open(0) < 0)
+ return 1;
+ uffdio_register.range.start = (unsigned long) area_dst;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ fprintf(stderr, "register failure\n"), exit(1);
+
+ expected_ioctls = EXPECTED_IOCTLS;
+ if ((uffdio_register.ioctls & expected_ioctls) !=
+ expected_ioctls)
+ fprintf(stderr,
+ "unexpected missing ioctl for anon memory\n"),
+ exit(1);
+
+ if (uffdio_zeropage(uffd, 0)) {
+ if (my_bcmp(area_dst, zeropage, page_size))
+ fprintf(stderr, "zeropage is not zero\n"), exit(1);
+ }
+
+ close(uffd);
+ printf("done.\n");
+ return 0;
+}
+
+static int userfaultfd_events_test(void)
+{
+ struct uffdio_register uffdio_register;
+ unsigned long expected_ioctls;
+ unsigned long userfaults;
+ pthread_t uffd_mon;
+ int err, features;
+ pid_t pid;
+ char c;
+
+ printf("testing events (fork, remap, remove): ");
+ fflush(stdout);
+
+ if (release_pages(area_dst))
+ return 1;
+
+ features = UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_EVENT_REMAP |
+ UFFD_FEATURE_EVENT_REMOVE;
+ if (userfaultfd_open(features) < 0)
+ return 1;
+ fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+
+ uffdio_register.range.start = (unsigned long) area_dst;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ fprintf(stderr, "register failure\n"), exit(1);
+
+ expected_ioctls = EXPECTED_IOCTLS;
+ if ((uffdio_register.ioctls & expected_ioctls) !=
+ expected_ioctls)
+ fprintf(stderr,
+ "unexpected missing ioctl for anon memory\n"),
+ exit(1);
+
+ if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, NULL))
+ perror("uffd_poll_thread create"), exit(1);
+
+ pid = fork();
+ if (pid < 0)
+ perror("fork"), exit(1);
+
+ if (!pid)
+ return faulting_process();
+
+ waitpid(pid, &err, 0);
+ if (err)
+ fprintf(stderr, "faulting process failed\n"), exit(1);
+
+ if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+ perror("pipe write"), exit(1);
+ if (pthread_join(uffd_mon, (void **)&userfaults))
+ return 1;
+
+ close(uffd);
+ printf("userfaults: %ld\n", userfaults);
+
+ return userfaults != nr_pages;
+}
+
+static int userfaultfd_stress(void)
+{
+ void *area;
+ char *tmp_area;
+ unsigned long nr;
+ struct uffdio_register uffdio_register;
+ unsigned long cpu;
+ int err;
+ unsigned long userfaults[nr_cpus];
+
+ allocate_area((void **)&area_src);
+ if (!area_src)
+ return 1;
+ allocate_area((void **)&area_dst);
+ if (!area_dst)
+ return 1;
+
+ if (userfaultfd_open(0) < 0)
+ return 1;
+
count_verify = malloc(nr_pages * sizeof(unsigned long long));
if (!count_verify) {
perror("count_verify");
@@ -528,9 +856,7 @@ static int userfaultfd_stress(void)
fprintf(stderr, "register failure\n");
return 1;
}
- expected_ioctls = (1 << _UFFDIO_WAKE) |
- (1 << _UFFDIO_COPY) |
- (1 << _UFFDIO_ZEROPAGE);
+ expected_ioctls = EXPECTED_IOCTLS;
if ((uffdio_register.ioctls & expected_ioctls) !=
expected_ioctls) {
fprintf(stderr,
@@ -562,10 +888,8 @@ static int userfaultfd_stress(void)
* MADV_DONTNEED only after the UFFDIO_REGISTER, so it's
* required to MADV_DONTNEED here.
*/
- if (madvise(area_dst, nr_pages * page_size, MADV_DONTNEED)) {
- perror("madvise 2");
+ if (release_pages(area_dst))
return 1;
- }
/* bounce pass */
if (stress(userfaults))
@@ -603,9 +927,15 @@ static int userfaultfd_stress(void)
printf("\n");
}
- return err;
+ if (err)
+ return err;
+
+ close(uffd);
+ return userfaultfd_zeropage_test() || userfaultfd_events_test();
}
+#ifndef HUGETLB_TEST
+
int main(int argc, char **argv)
{
if (argc < 3)
@@ -632,6 +962,74 @@ int main(int argc, char **argv)
return userfaultfd_stress();
}
+#else /* HUGETLB_TEST */
+
+/*
+ * Copied from mlock2-tests.c
+ */
+unsigned long default_huge_page_size(void)
+{
+ unsigned long hps = 0;
+ char *line = NULL;
+ size_t linelen = 0;
+ FILE *f = fopen("/proc/meminfo", "r");
+
+ if (!f)
+ return 0;
+ while (getline(&line, &linelen, f) > 0) {
+ if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) {
+ hps <<= 10;
+ break;
+ }
+ }
+
+ free(line);
+ fclose(f);
+ return hps;
+}
+
+int main(int argc, char **argv)
+{
+ if (argc < 4)
+ fprintf(stderr, "Usage: <MiB> <bounces> <hugetlbfs_file>\n"),
+ exit(1);
+ nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+ page_size = default_huge_page_size();
+ if (!page_size)
+ fprintf(stderr, "Unable to determine huge page size\n"),
+ exit(2);
+ if ((unsigned long) area_count(NULL, 0) + sizeof(unsigned long long) * 2
+ > page_size)
+ fprintf(stderr, "Impossible to run this test\n"), exit(2);
+ nr_pages_per_cpu = atol(argv[1]) * 1024*1024 / page_size /
+ nr_cpus;
+ if (!nr_pages_per_cpu) {
+ fprintf(stderr, "invalid MiB\n");
+ fprintf(stderr, "Usage: <MiB> <bounces>\n"), exit(1);
+ }
+ bounces = atoi(argv[2]);
+ if (bounces <= 0) {
+ fprintf(stderr, "invalid bounces\n");
+ fprintf(stderr, "Usage: <MiB> <bounces>\n"), exit(1);
+ }
+ nr_pages = nr_pages_per_cpu * nr_cpus;
+ huge_fd = open(argv[3], O_CREAT | O_RDWR, 0755);
+ if (huge_fd < 0) {
+ fprintf(stderr, "Open of %s failed", argv[3]);
+ perror("open");
+ exit(1);
+ }
+ if (ftruncate(huge_fd, 0)) {
+ fprintf(stderr, "ftruncate %s to size 0 failed", argv[3]);
+ perror("ftruncate");
+ exit(1);
+ }
+ printf("nr_pages: %lu, nr_pages_per_cpu: %lu\n",
+ nr_pages, nr_pages_per_cpu);
+ return userfaultfd_stress();
+}
+
+#endif
#else /* __NR_userfaultfd */
#warning "missing __NR_userfaultfd definition"