root/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */

#include <test_progs.h>

#include "test_btf_map_in_map.skel.h"

static int duration;

static __u32 bpf_map_id(struct bpf_map *map)
{
        struct bpf_map_info info;
        __u32 info_len = sizeof(info);
        int err;

        memset(&info, 0, info_len);
        err = bpf_map_get_info_by_fd(bpf_map__fd(map), &info, &info_len);
        if (err)
                return 0;
        return info.id;
}

static void test_lookup_update(void)
{
        int map1_fd, map2_fd, map3_fd, map4_fd, map5_fd, map1_id, map2_id;
        int outer_arr_fd, outer_hash_fd, outer_arr_dyn_fd;
        struct test_btf_map_in_map *skel;
        int err, key = 0, val, i;

        skel = test_btf_map_in_map__open_and_load();
        if (CHECK(!skel, "skel_open", "failed to open&load skeleton\n"))
                return;

        err = test_btf_map_in_map__attach(skel);
        if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
                goto cleanup;

        map1_fd = bpf_map__fd(skel->maps.inner_map1);
        map2_fd = bpf_map__fd(skel->maps.inner_map2);
        map3_fd = bpf_map__fd(skel->maps.inner_map3);
        map4_fd = bpf_map__fd(skel->maps.inner_map4);
        map5_fd = bpf_map__fd(skel->maps.inner_map5);
        outer_arr_dyn_fd = bpf_map__fd(skel->maps.outer_arr_dyn);
        outer_arr_fd = bpf_map__fd(skel->maps.outer_arr);
        outer_hash_fd = bpf_map__fd(skel->maps.outer_hash);

        /* inner1 = input, inner2 = input + 1, inner3 = input + 2 */
        bpf_map_update_elem(outer_arr_fd, &key, &map1_fd, 0);
        bpf_map_update_elem(outer_hash_fd, &key, &map2_fd, 0);
        bpf_map_update_elem(outer_arr_dyn_fd, &key, &map3_fd, 0);
        skel->bss->input = 1;
        usleep(1);
        bpf_map_lookup_elem(map1_fd, &key, &val);
        CHECK(val != 1, "inner1", "got %d != exp %d\n", val, 1);
        bpf_map_lookup_elem(map2_fd, &key, &val);
        CHECK(val != 2, "inner2", "got %d != exp %d\n", val, 2);
        bpf_map_lookup_elem(map3_fd, &key, &val);
        CHECK(val != 3, "inner3", "got %d != exp %d\n", val, 3);

        /* inner2 = input, inner1 = input + 1, inner4 = input + 2 */
        bpf_map_update_elem(outer_arr_fd, &key, &map2_fd, 0);
        bpf_map_update_elem(outer_hash_fd, &key, &map1_fd, 0);
        bpf_map_update_elem(outer_arr_dyn_fd, &key, &map4_fd, 0);
        skel->bss->input = 3;
        usleep(1);
        bpf_map_lookup_elem(map1_fd, &key, &val);
        CHECK(val != 4, "inner1", "got %d != exp %d\n", val, 4);
        bpf_map_lookup_elem(map2_fd, &key, &val);
        CHECK(val != 3, "inner2", "got %d != exp %d\n", val, 3);
        bpf_map_lookup_elem(map4_fd, &key, &val);
        CHECK(val != 5, "inner4", "got %d != exp %d\n", val, 5);

        /* inner5 = input + 2 */
        bpf_map_update_elem(outer_arr_dyn_fd, &key, &map5_fd, 0);
        skel->bss->input = 5;
        usleep(1);
        bpf_map_lookup_elem(map5_fd, &key, &val);
        CHECK(val != 7, "inner5", "got %d != exp %d\n", val, 7);

        for (i = 0; i < 5; i++) {
                val = i % 2 ? map1_fd : map2_fd;
                err = bpf_map_update_elem(outer_hash_fd, &key, &val, 0);
                if (CHECK_FAIL(err)) {
                        printf("failed to update hash_of_maps on iter #%d\n", i);
                        goto cleanup;
                }
                err = bpf_map_update_elem(outer_arr_fd, &key, &val, 0);
                if (CHECK_FAIL(err)) {
                        printf("failed to update array_of_maps on iter #%d\n", i);
                        goto cleanup;
                }
                val = i % 2 ? map4_fd : map5_fd;
                err = bpf_map_update_elem(outer_arr_dyn_fd, &key, &val, 0);
                if (CHECK_FAIL(err)) {
                        printf("failed to update array_of_maps (dyn) on iter #%d\n", i);
                        goto cleanup;
                }
        }

        map1_id = bpf_map_id(skel->maps.inner_map1);
        map2_id = bpf_map_id(skel->maps.inner_map2);
        CHECK(map1_id == 0, "map1_id", "failed to get ID 1\n");
        CHECK(map2_id == 0, "map2_id", "failed to get ID 2\n");

cleanup:
        test_btf_map_in_map__destroy(skel);
}

static void test_diff_size(void)
{
        struct test_btf_map_in_map *skel;
        int err, inner_map_fd, zero = 0;

        skel = test_btf_map_in_map__open_and_load();
        if (CHECK(!skel, "skel_open", "failed to open&load skeleton\n"))
                return;

        inner_map_fd = bpf_map__fd(skel->maps.sockarr_sz2);
        err = bpf_map_update_elem(bpf_map__fd(skel->maps.outer_sockarr), &zero,
                                  &inner_map_fd, 0);
        CHECK(err, "outer_sockarr inner map size check",
              "cannot use a different size inner_map\n");

        inner_map_fd = bpf_map__fd(skel->maps.inner_map_sz2);
        err = bpf_map_update_elem(bpf_map__fd(skel->maps.outer_arr), &zero,
                                  &inner_map_fd, 0);
        CHECK(!err, "outer_arr inner map size check",
              "incorrectly updated with a different size inner_map\n");

        test_btf_map_in_map__destroy(skel);
}

void test_btf_map_in_map(void)
{
        if (test__start_subtest("lookup_update"))
                test_lookup_update();

        if (test__start_subtest("diff_size"))
                test_diff_size();
}