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.o";
43 	__u32 retval;
44 	struct bpf_object *obj;
45 	int err, prog_fd;
46 
47 	err = bpf_prog_load(file, BPF_PROG_TYPE_CGROUP_SKB, &obj, &prog_fd);
48 	if (CHECK(err, "load program", "error %d loading %s\n", err, file))
49 		return;
50 
51 	err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
52 				NULL, NULL, &retval, &duration);
53 	CHECK(err || retval, "pass global func args run",
54 	      "err %d errno %d retval %d duration %d\n",
55 	      err, errno, retval, duration);
56 
57 	test_global_func_args0(obj);
58 
59 	bpf_object__close(obj);
60 }
61