LXR linux/tools/testing/selftests/bpf/progs/bpf_iter_test

   1// SPDX-License-Identifier: GPL-2.0
   2/* Copyright (c) 2020 Facebook */
   3#include "bpf_iter.h"
   4#include <bpf/bpf_helpers.h>
   5
   6char _license[] SEC("license") = "GPL";
   7
   8__u32 map1_id = 0, map2_id = 0;
   9__u32 map1_accessed = 0, map2_accessed = 0;
  10__u64 map1_seqnum = 0, map2_seqnum1 = 0, map2_seqnum2 = 0;
  11
  12static volatile const __u32 print_len;
  13static volatile const __u32 ret1;
  14
  15SEC("iter/bpf_map")
  16int dump_bpf_map(struct bpf_iter__bpf_map *ctx)
  17{
  18        struct seq_file *seq = ctx->meta->seq;
  19        struct bpf_map *map = ctx->map;
  20        __u64 seq_num;
  21        int i, ret = 0;
  22
  23        if (map == (void *)0)
  24                return 0;
  25
  26        /* only dump map1_id and map2_id */
  27        if (map->id != map1_id && map->id != map2_id)
  28                return 0;
  29
  30        seq_num = ctx->meta->seq_num;
  31        if (map->id == map1_id) {
  32                map1_seqnum = seq_num;
  33                map1_accessed++;
  34        }
  35
  36        if (map->id == map2_id) {
  37                if (map2_accessed == 0) {
  38                        map2_seqnum1 = seq_num;
  39                        if (ret1)
  40                                ret = 1;
  41                } else {
  42                        map2_seqnum2 = seq_num;
  43                }
  44                map2_accessed++;
  45        }
  46
  47        /* fill seq_file buffer */
  48        for (i = 0; i < print_len; i++)
  49                bpf_seq_write(seq, &seq_num, sizeof(seq_num));
  50
  51        return ret;
  52}
  53