1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2021 Facebook */
3
4#include "vmlinux.h"
5#include <bpf/bpf_helpers.h>
6#include <bpf/bpf_tracing.h>
7
8struct my_key { long x; };
9struct my_value { long x; };
10
11struct {
12	__uint(type, BPF_MAP_TYPE_HASH);
13	__type(key, struct my_key);
14	__type(value, struct my_value);
15	__uint(max_entries, 16);
16} map1 SEC(".maps");
17
18 /* Matches map2 definition in linked_maps2.c. Order of the attributes doesn't
19  * matter.
20  */
21typedef struct {
22	__uint(max_entries, 8);
23	__type(key, int);
24	__type(value, int);
25	__uint(type, BPF_MAP_TYPE_ARRAY);
26} map2_t;
27
28extern map2_t map2 SEC(".maps");
29
30/* This should be the winning map definition, but we have no way of verifying,
31 * so we just make sure that it links and works without errors
32 */
33struct {
34	__uint(type, BPF_MAP_TYPE_ARRAY);
35	__type(key, int);
36	__type(value, int);
37	__uint(max_entries, 16);
38} map_weak __weak SEC(".maps");
39
40int output_first1;
41int output_second1;
42int output_weak1;
43
44SEC("raw_tp/sys_enter")
45int BPF_PROG(handler_enter1)
46{
47	/* update values with key = 1 */
48	int key = 1, val = 1;
49	struct my_key key_struct = { .x = 1 };
50	struct my_value val_struct = { .x = 1000 };
51
52	bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);
53	bpf_map_update_elem(&map2, &key, &val, 0);
54	bpf_map_update_elem(&map_weak, &key, &val, 0);
55
56	return 0;
57}
58
59SEC("raw_tp/sys_exit")
60int BPF_PROG(handler_exit1)
61{
62	/* lookup values with key = 2, set in another file */
63	int key = 2, *val;
64	struct my_key key_struct = { .x = 2 };
65	struct my_value *value_struct;
66
67	value_struct = bpf_map_lookup_elem(&map1, &key_struct);
68	if (value_struct)
69		output_first1 = value_struct->x;
70
71	val = bpf_map_lookup_elem(&map2, &key);
72	if (val)
73		output_second1 = *val;
74
75	val = bpf_map_lookup_elem(&map_weak, &key);
76	if (val)
77		output_weak1 = *val;
78
79	return 0;
80}
81
82char LICENSE[] SEC("license") = "GPL";
83