// clang-format off #include #include // clang-format on struct inner_map_type { __uint(type, BPF_MAP_TYPE_ARRAY); __type(key, __u32); __type(value, __u32); __uint(max_entries, 10); // Size is different from the outer map __uint(map_flags, BPF_F_INNER_MAP); // Flag required due to ^^^ } inner_map SEC(".maps"); struct { __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); __type(key, __u32); // value omitted as should be fixed by loader __uint(max_entries, 1); __array(values, struct inner_map_type); } outer_array_map SEC(".maps") = { .values = { [0] = &inner_map, }, }; struct { __uint(type, BPF_MAP_TYPE_HASH_OF_MAPS); __type(key, __u32); // value omitted as should be fixed by loader __uint(max_entries, 1); __array(values, struct inner_map_type); } outer_hash_map SEC(".maps") = { .values = { [0] = &inner_map, }, }; static int map_in_map_test(void *outer_map) { int key = 0; int value = 42; void *inner_map; inner_map = bpf_map_lookup_elem(outer_map, &key); if (!inner_map) return 0; bpf_map_update_elem(inner_map, &key, &value, 0); return 0; } SEC("xdp") int mim_test_array(struct xdp_md *ctx) { map_in_map_test(&outer_array_map); return XDP_PASS; } SEC("xdp") int mim_test_hash(struct xdp_md *ctx) { map_in_map_test(&outer_hash_map); return XDP_PASS; } char _license[] SEC("license") = "GPL";