diff options
Diffstat (limited to 'tools/testing/selftests/mm/guard-regions.c')
| -rw-r--r-- | tools/testing/selftests/mm/guard-regions.c | 73 |
1 files changed, 67 insertions, 6 deletions
diff --git a/tools/testing/selftests/mm/guard-regions.c b/tools/testing/selftests/mm/guard-regions.c index b3d0e2771096..0cd9d236649d 100644 --- a/tools/testing/selftests/mm/guard-regions.c +++ b/tools/testing/selftests/mm/guard-regions.c @@ -8,6 +8,7 @@ #include <fcntl.h> #include <linux/limits.h> #include <linux/userfaultfd.h> +#include <linux/fs.h> #include <setjmp.h> #include <signal.h> #include <stdbool.h> @@ -271,12 +272,16 @@ FIXTURE_SETUP(guard_regions) self->page_size = (unsigned long)sysconf(_SC_PAGESIZE); setup_sighandler(); - if (variant->backing == ANON_BACKED) + switch (variant->backing) { + case ANON_BACKED: return; - - self->fd = open_file( - variant->backing == SHMEM_BACKED ? "/tmp/" : "", - self->path); + case LOCAL_FILE_BACKED: + self->fd = open_file("", self->path); + break; + case SHMEM_BACKED: + self->fd = memfd_create(self->path, 0); + break; + } /* We truncate file to at least 100 pages, tests can modify as needed. */ ASSERT_EQ(ftruncate(self->fd, 100 * self->page_size), 0); @@ -1696,7 +1701,7 @@ TEST_F(guard_regions, readonly_file) char *ptr; int i; - if (variant->backing == ANON_BACKED) + if (variant->backing != LOCAL_FILE_BACKED) SKIP(return, "Read-only test specific to file-backed"); /* Map shared so we can populate with pattern, populate it, unmap. */ @@ -2071,4 +2076,60 @@ TEST_F(guard_regions, pagemap) ASSERT_EQ(munmap(ptr, 10 * page_size), 0); } +/* + * Assert that PAGEMAP_SCAN correctly reports guard region ranges. + */ +TEST_F(guard_regions, pagemap_scan) +{ + const unsigned long page_size = self->page_size; + struct page_region pm_regs[10]; + struct pm_scan_arg pm_scan_args = { + .size = sizeof(struct pm_scan_arg), + .category_anyof_mask = PAGE_IS_GUARD, + .return_mask = PAGE_IS_GUARD, + .vec = (long)&pm_regs, + .vec_len = ARRAY_SIZE(pm_regs), + }; + int proc_fd, i; + char *ptr; + + proc_fd = open("/proc/self/pagemap", O_RDONLY); + ASSERT_NE(proc_fd, -1); + + ptr = mmap_(self, variant, NULL, 10 * page_size, + PROT_READ | PROT_WRITE, 0, 0); + ASSERT_NE(ptr, MAP_FAILED); + + pm_scan_args.start = (long)ptr; + pm_scan_args.end = (long)ptr + 10 * page_size; + ASSERT_EQ(ioctl(proc_fd, PAGEMAP_SCAN, &pm_scan_args), 0); + ASSERT_EQ(pm_scan_args.walk_end, (long)ptr + 10 * page_size); + + /* Install a guard region in every other page. */ + for (i = 0; i < 10; i += 2) { + char *ptr_p = &ptr[i * page_size]; + + ASSERT_EQ(syscall(__NR_madvise, ptr_p, page_size, MADV_GUARD_INSTALL), 0); + } + + /* + * Assert ioctl() returns the count of located regions, where each + * region spans every other page within the range of 10 pages. + */ + ASSERT_EQ(ioctl(proc_fd, PAGEMAP_SCAN, &pm_scan_args), 5); + ASSERT_EQ(pm_scan_args.walk_end, (long)ptr + 10 * page_size); + + /* Re-read from pagemap, and assert guard regions are detected. */ + for (i = 0; i < 5; i++) { + long ptr_p = (long)&ptr[2 * i * page_size]; + + ASSERT_EQ(pm_regs[i].start, ptr_p); + ASSERT_EQ(pm_regs[i].end, ptr_p + page_size); + ASSERT_EQ(pm_regs[i].categories, PAGE_IS_GUARD); + } + + ASSERT_EQ(close(proc_fd), 0); + ASSERT_EQ(munmap(ptr, 10 * page_size), 0); +} + TEST_HARNESS_MAIN |