tools/testing/selftests/bpf/prog_tests/global_func_args.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include "test_progs.h"
   3 #include "network_helpers.h"
   4
   5 static __u32 duration;
   6
   7 static void test_global_func_args0(struct bpf_object *obj)
   8 {
   9         int err, i, map_fd, actual_value;
  10         const char *map_name = "values";
  11
  12         map_fd = bpf_find_map(__func__, obj, map_name);
  13         if (CHECK(map_fd < 0, "bpf_find_map", "cannot find BPF map %s: %s\n",
  14                 map_name, strerror(errno)))
  15                 return;
  16
  17         struct {
  18                 const char *descr;
  19                 int expected_value;
  20         } tests[] = {
  21                 {"passing NULL pointer", 0},
  22                 {"returning value", 1},
  23                 {"reading local variable", 100 },
  24                 {"writing local variable", 101 },
  25                 {"reading global variable", 42 },
  26                 {"writing global variable", 43 },
  27                 {"writing to pointer-to-pointer", 1 },
  28         };
  29
  30         for (i = 0; i < ARRAY_SIZE(tests); ++i) {
  31                 const int expected_value = tests[i].expected_value;
  32
  33                 err = bpf_map_lookup_elem(map_fd, &i, &actual_value);
  34
  35                 CHECK(err || actual_value != expected_value, tests[i].descr,
  36                          "err %d result %d expected %d\n", err, actual_value, expected_value);
  37         }
  38 }
  39
  40 void test_global_func_args(void)
  41 {
  42         const char *file = "./test_global_func_args.bpf.o";
  43         struct bpf_object *obj;
  44         int err, prog_fd;
  45         LIBBPF_OPTS(bpf_test_run_opts, topts,
  46                 .data_in = &pkt_v4,
  47                 .data_size_in = sizeof(pkt_v4),
  48                 .repeat = 1,
  49         );
  50
  51         err = bpf_prog_test_load(file, BPF_PROG_TYPE_CGROUP_SKB, &obj, &prog_fd);
  52         if (CHECK(err, "load program", "error %d loading %s\n", err, file))
  53                 return;
  54
  55         err = bpf_prog_test_run_opts(prog_fd, &topts);
  56         ASSERT_OK(err, "test_run");
  57         ASSERT_OK(topts.retval, "test_run retval");
  58
  59         test_global_func_args0(obj);
  60
  61         bpf_object__close(obj);
  62 }