LXR iproute2/examples/bpf/legacy/bpf_map_in

   1#include "../../../include/bpf_api.h"
   2
   3#define MAP_INNER_ID    42
   4
   5struct bpf_elf_map __section_maps map_inner = {
   6        .type           = BPF_MAP_TYPE_ARRAY,
   7        .size_key       = sizeof(uint32_t),
   8        .size_value     = sizeof(uint32_t),
   9        .id             = MAP_INNER_ID,
  10        .inner_idx      = 0,
  11        .pinning        = PIN_GLOBAL_NS,
  12        .max_elem       = 1,
  13};
  14
  15struct bpf_elf_map __section_maps map_outer = {
  16        .type           = BPF_MAP_TYPE_ARRAY_OF_MAPS,
  17        .size_key       = sizeof(uint32_t),
  18        .size_value     = sizeof(uint32_t),
  19        .inner_id       = MAP_INNER_ID,
  20        .pinning        = PIN_GLOBAL_NS,
  21        .max_elem       = 1,
  22};
  23
  24__section("egress")
  25int emain(struct __sk_buff *skb)
  26{
  27        struct bpf_elf_map *map_inner;
  28        int key = 0, *val;
  29
  30        map_inner = map_lookup_elem(&map_outer, &key);
  31        if (map_inner) {
  32                val = map_lookup_elem(map_inner, &key);
  33                if (val)
  34                        lock_xadd(val, 1);
  35        }
  36
  37        return BPF_H_DEFAULT;
  38}
  39
  40__section("ingress")
  41int imain(struct __sk_buff *skb)
  42{
  43        struct bpf_elf_map *map_inner;
  44        int key = 0, *val;
  45
  46        map_inner = map_lookup_elem(&map_outer, &key);
  47        if (map_inner) {
  48                val = map_lookup_elem(map_inner, &key);
  49                if (val)
  50                        printt("map val: %d\n", *val);
  51        }
  52
  53        return BPF_H_DEFAULT;
  54}
  55
  56BPF_LICENSE("GPL");
  57