diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/mmap.c')
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/mmap.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/mmap.c b/tools/testing/selftests/bpf/prog_tests/mmap.c new file mode 100644 index 000000000000..051a6d48762c --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/mmap.c @@ -0,0 +1,220 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include <sys/mman.h> + +struct map_data { + __u64 val[512 * 4]; +}; + +struct bss_data { + __u64 in_val; + __u64 out_val; +}; + +static size_t roundup_page(size_t sz) +{ + long page_size = sysconf(_SC_PAGE_SIZE); + return (sz + page_size - 1) / page_size * page_size; +} + +void test_mmap(void) +{ + const char *file = "test_mmap.o"; + const char *probe_name = "raw_tracepoint/sys_enter"; + const char *tp_name = "sys_enter"; + const size_t bss_sz = roundup_page(sizeof(struct bss_data)); + const size_t map_sz = roundup_page(sizeof(struct map_data)); + const int zero = 0, one = 1, two = 2, far = 1500; + const long page_size = sysconf(_SC_PAGE_SIZE); + int err, duration = 0, i, data_map_fd; + struct bpf_program *prog; + struct bpf_object *obj; + struct bpf_link *link = NULL; + struct bpf_map *data_map, *bss_map; + void *bss_mmaped = NULL, *map_mmaped = NULL, *tmp1, *tmp2; + volatile struct bss_data *bss_data; + volatile struct map_data *map_data; + __u64 val = 0; + + obj = bpf_object__open_file("test_mmap.o", NULL); + if (CHECK(IS_ERR(obj), "obj_open", "failed to open '%s': %ld\n", + file, PTR_ERR(obj))) + return; + prog = bpf_object__find_program_by_title(obj, probe_name); + if (CHECK(!prog, "find_probe", "prog '%s' not found\n", probe_name)) + goto cleanup; + err = bpf_object__load(obj); + if (CHECK(err, "obj_load", "failed to load prog '%s': %d\n", + probe_name, err)) + goto cleanup; + + bss_map = bpf_object__find_map_by_name(obj, "test_mma.bss"); + if (CHECK(!bss_map, "find_bss_map", ".bss map not found\n")) + goto cleanup; + data_map = bpf_object__find_map_by_name(obj, "data_map"); + if (CHECK(!data_map, "find_data_map", "data_map map not found\n")) + goto cleanup; + data_map_fd = bpf_map__fd(data_map); + + bss_mmaped = mmap(NULL, bss_sz, PROT_READ | PROT_WRITE, MAP_SHARED, + bpf_map__fd(bss_map), 0); + if (CHECK(bss_mmaped == MAP_FAILED, "bss_mmap", + ".bss mmap failed: %d\n", errno)) { + bss_mmaped = NULL; + goto cleanup; + } + /* map as R/W first */ + map_mmaped = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED, + data_map_fd, 0); + if (CHECK(map_mmaped == MAP_FAILED, "data_mmap", + "data_map mmap failed: %d\n", errno)) { + map_mmaped = NULL; + goto cleanup; + } + + bss_data = bss_mmaped; + map_data = map_mmaped; + + CHECK_FAIL(bss_data->in_val); + CHECK_FAIL(bss_data->out_val); + CHECK_FAIL(map_data->val[0]); + CHECK_FAIL(map_data->val[1]); + CHECK_FAIL(map_data->val[2]); + CHECK_FAIL(map_data->val[far]); + + link = bpf_program__attach_raw_tracepoint(prog, tp_name); + if (CHECK(IS_ERR(link), "attach_raw_tp", "err %ld\n", PTR_ERR(link))) + goto cleanup; + + bss_data->in_val = 123; + val = 111; + CHECK_FAIL(bpf_map_update_elem(data_map_fd, &zero, &val, 0)); + + usleep(1); + + CHECK_FAIL(bss_data->in_val != 123); + CHECK_FAIL(bss_data->out_val != 123); + CHECK_FAIL(map_data->val[0] != 111); + CHECK_FAIL(map_data->val[1] != 222); + CHECK_FAIL(map_data->val[2] != 123); + CHECK_FAIL(map_data->val[far] != 3 * 123); + + CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &zero, &val)); + CHECK_FAIL(val != 111); + CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &one, &val)); + CHECK_FAIL(val != 222); + CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &two, &val)); + CHECK_FAIL(val != 123); + CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &far, &val)); + CHECK_FAIL(val != 3 * 123); + + /* data_map freeze should fail due to R/W mmap() */ + err = bpf_map_freeze(data_map_fd); + if (CHECK(!err || errno != EBUSY, "no_freeze", + "data_map freeze succeeded: err=%d, errno=%d\n", err, errno)) + goto cleanup; + + /* unmap R/W mapping */ + err = munmap(map_mmaped, map_sz); + map_mmaped = NULL; + if (CHECK(err, "data_map_munmap", "data_map munmap failed: %d\n", errno)) + goto cleanup; + + /* re-map as R/O now */ + map_mmaped = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0); + if (CHECK(map_mmaped == MAP_FAILED, "data_mmap", + "data_map R/O mmap failed: %d\n", errno)) { + map_mmaped = NULL; + goto cleanup; + } + map_data = map_mmaped; + + /* map/unmap in a loop to test ref counting */ + for (i = 0; i < 10; i++) { + int flags = i % 2 ? PROT_READ : PROT_WRITE; + void *p; + + p = mmap(NULL, map_sz, flags, MAP_SHARED, data_map_fd, 0); + if (CHECK_FAIL(p == MAP_FAILED)) + goto cleanup; + err = munmap(p, map_sz); + if (CHECK_FAIL(err)) + goto cleanup; + } + + /* data_map freeze should now succeed due to no R/W mapping */ + err = bpf_map_freeze(data_map_fd); + if (CHECK(err, "freeze", "data_map freeze failed: err=%d, errno=%d\n", + err, errno)) + goto cleanup; + + /* mapping as R/W now should fail */ + tmp1 = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED, + data_map_fd, 0); + if (CHECK(tmp1 != MAP_FAILED, "data_mmap", "mmap succeeded\n")) { + munmap(tmp1, map_sz); + goto cleanup; + } + + bss_data->in_val = 321; + usleep(1); + CHECK_FAIL(bss_data->in_val != 321); + CHECK_FAIL(bss_data->out_val != 321); + CHECK_FAIL(map_data->val[0] != 111); + CHECK_FAIL(map_data->val[1] != 222); + CHECK_FAIL(map_data->val[2] != 321); + CHECK_FAIL(map_data->val[far] != 3 * 321); + + /* check some more advanced mmap() manipulations */ + + /* map all but last page: pages 1-3 mapped */ + tmp1 = mmap(NULL, 3 * page_size, PROT_READ, MAP_SHARED, + data_map_fd, 0); + if (CHECK(tmp1 == MAP_FAILED, "adv_mmap1", "errno %d\n", errno)) + goto cleanup; + + /* unmap second page: pages 1, 3 mapped */ + err = munmap(tmp1 + page_size, page_size); + if (CHECK(err, "adv_mmap2", "errno %d\n", errno)) { + munmap(tmp1, map_sz); + goto cleanup; + } + + /* map page 2 back */ + tmp2 = mmap(tmp1 + page_size, page_size, PROT_READ, + MAP_SHARED | MAP_FIXED, data_map_fd, 0); + if (CHECK(tmp2 == MAP_FAILED, "adv_mmap3", "errno %d\n", errno)) { + munmap(tmp1, page_size); + munmap(tmp1 + 2*page_size, page_size); + goto cleanup; + } + CHECK(tmp1 + page_size != tmp2, "adv_mmap4", + "tmp1: %p, tmp2: %p\n", tmp1, tmp2); + + /* re-map all 4 pages */ + tmp2 = mmap(tmp1, 4 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED, + data_map_fd, 0); + if (CHECK(tmp2 == MAP_FAILED, "adv_mmap5", "errno %d\n", errno)) { + munmap(tmp1, 3 * page_size); /* unmap page 1 */ + goto cleanup; + } + CHECK(tmp1 != tmp2, "adv_mmap6", "tmp1: %p, tmp2: %p\n", tmp1, tmp2); + + map_data = tmp2; + CHECK_FAIL(bss_data->in_val != 321); + CHECK_FAIL(bss_data->out_val != 321); + CHECK_FAIL(map_data->val[0] != 111); + CHECK_FAIL(map_data->val[1] != 222); + CHECK_FAIL(map_data->val[2] != 321); + CHECK_FAIL(map_data->val[far] != 3 * 321); + + munmap(tmp2, 4 * page_size); +cleanup: + if (bss_mmaped) + CHECK_FAIL(munmap(bss_mmaped, bss_sz)); + if (map_mmaped) + CHECK_FAIL(munmap(map_mmaped, map_sz)); + if (!IS_ERR_OR_NULL(link)) + bpf_link__destroy(link); + bpf_object__close(obj); +} |