tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (c) 2020 Facebook */
   3 #include "bpf_iter.h"
   4 #include <bpf/bpf_helpers.h>
   5
   6 char _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
  12 static volatile const __u32 print_len;
  13 static volatile const __u32 ret1;
  14
  15 SEC("iter/bpf_map")
  16 int 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 }