1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020 Facebook */
3 #include "bpf_iter.h"
4 #include <bpf/bpf_helpers.h>
5 #include <bpf/bpf_tracing.h>
6
7 char _license[] SEC("license") = "GPL";
8
9 struct {
10 __uint(type, BPF_MAP_TYPE_ARRAY);
11 __uint(max_entries, 3);
12 __type(key, __u32);
13 __type(value, __u64);
14 } arraymap1 SEC(".maps");
15
16 struct {
17 __uint(type, BPF_MAP_TYPE_HASH);
18 __uint(max_entries, 10);
19 __type(key, __u64);
20 __type(value, __u32);
21 } hashmap1 SEC(".maps");
22
23 __u32 key_sum = 0;
24 __u64 val_sum = 0;
25
26 SEC("iter/bpf_map_elem")
dump_bpf_array_map(struct bpf_iter__bpf_map_elem * ctx)27 int dump_bpf_array_map(struct bpf_iter__bpf_map_elem *ctx)
28 {
29 __u32 *hmap_val, *key = ctx->key;
30 __u64 *val = ctx->value;
31
32 if (key == (void *)0 || val == (void *)0)
33 return 0;
34
35 bpf_seq_write(ctx->meta->seq, key, sizeof(__u32));
36 bpf_seq_write(ctx->meta->seq, val, sizeof(__u64));
37 key_sum += *key;
38 val_sum += *val;
39
40 /* workaround - It's necessary to do this convoluted (val, key)
41 * write into hashmap1, instead of simply doing
42 * bpf_map_update_elem(&hashmap1, val, key, BPF_ANY);
43 * because key has MEM_RDONLY flag and bpf_map_update elem expects
44 * types without this flag
45 */
46 bpf_map_update_elem(&hashmap1, val, val, BPF_ANY);
47 hmap_val = bpf_map_lookup_elem(&hashmap1, val);
48 if (hmap_val)
49 *hmap_val = *key;
50
51 *val = *key;
52 return 0;
53 }
54