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

   1// SPDX-License-Identifier: GPL-2.0
   2/* Copyright (c) 2020 Facebook */
   3#define bpf_iter_meta bpf_iter_meta___not_used
   4#define bpf_iter__bpf_map bpf_iter__bpf_map___not_used
   5#include "vmlinux.h"
   6#undef bpf_iter_meta
   7#undef bpf_iter__bpf_map
   8#include <bpf/bpf_helpers.h>
   9
  10char _license[] SEC("license") = "GPL";
  11
  12struct bpf_iter_meta {
  13        struct seq_file *seq;
  14        __u64 session_id;
  15        __u64 seq_num;
  16} __attribute__((preserve_access_index));
  17
  18struct bpf_iter__bpf_map {
  19        struct bpf_iter_meta *meta;
  20        struct bpf_map *map;
  21} __attribute__((preserve_access_index));
  22
  23__u32 map1_id = 0, map2_id = 0;
  24__u32 map1_accessed = 0, map2_accessed = 0;
  25__u64 map1_seqnum = 0, map2_seqnum1 = 0, map2_seqnum2 = 0;
  26
  27static volatile const __u32 print_len;
  28static volatile const __u32 ret1;
  29
  30SEC("iter/bpf_map")
  31int dump_bpf_map(struct bpf_iter__bpf_map *ctx)
  32{
  33        struct seq_file *seq = ctx->meta->seq;
  34        struct bpf_map *map = ctx->map;
  35        __u64 seq_num;
  36        int i, ret = 0;
  37
  38        if (map == (void *)0)
  39                return 0;
  40
  41        /* only dump map1_id and map2_id */
  42        if (map->id != map1_id && map->id != map2_id)
  43                return 0;
  44
  45        seq_num = ctx->meta->seq_num;
  46        if (map->id == map1_id) {
  47                map1_seqnum = seq_num;
  48                map1_accessed++;
  49        }
  50
  51        if (map->id == map2_id) {
  52                if (map2_accessed == 0) {
  53                        map2_seqnum1 = seq_num;
  54                        if (ret1)
  55                                ret = 1;
  56                } else {
  57                        map2_seqnum2 = seq_num;
  58                }
  59                map2_accessed++;
  60        }
  61
  62        /* fill seq_file buffer */
  63        for (i = 0; i < print_len; i++)
  64                bpf_seq_write(seq, &seq_num, sizeof(seq_num));
  65
  66        return ret;
  67}
  68