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

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (c) 2019 Facebook
   3
   4 #include <linux/bpf.h>
   5 #include <stdint.h>
   6 #include <bpf/bpf_helpers.h>
   7 #include <bpf/bpf_core_read.h>
   8
   9 char _license[] SEC("license") = "GPL";
  10
  11 struct {
  12         char in[256];
  13         char out[256];
  14 } data = {};
  15
  16 struct core_reloc_existence_output {
  17         int a_exists;
  18         int a_value;
  19         int b_exists;
  20         int b_value;
  21         int c_exists;
  22         int c_value;
  23         int arr_exists;
  24         int arr_value;
  25         int s_exists;
  26         int s_value;
  27 };
  28
  29 struct core_reloc_existence {
  30         struct {
  31                 int x;
  32         } s;
  33         int arr[1];
  34         int a;
  35         struct {
  36                 int b;
  37         };
  38         int c;
  39 };
  40
  41 SEC("raw_tracepoint/sys_enter")
  42 int test_core_existence(void *ctx)
  43 {
  44         struct core_reloc_existence *in = (void *)&data.in;
  45         struct core_reloc_existence_output *out = (void *)&data.out;
  46
  47         out->a_exists = bpf_core_field_exists(in->a);
  48         if (bpf_core_field_exists(in->a))
  49                 out->a_value = BPF_CORE_READ(in, a);
  50         else
  51                 out->a_value = 0xff000001u;
  52
  53         out->b_exists = bpf_core_field_exists(in->b);
  54         if (bpf_core_field_exists(in->b))
  55                 out->b_value = BPF_CORE_READ(in, b);
  56         else
  57                 out->b_value = 0xff000002u;
  58
  59         out->c_exists = bpf_core_field_exists(in->c);
  60         if (bpf_core_field_exists(in->c))
  61                 out->c_value = BPF_CORE_READ(in, c);
  62         else
  63                 out->c_value = 0xff000003u;
  64
  65         out->arr_exists = bpf_core_field_exists(in->arr);
  66         if (bpf_core_field_exists(in->arr))
  67                 out->arr_value = BPF_CORE_READ(in, arr[0]);
  68         else
  69                 out->arr_value = 0xff000004u;
  70
  71         out->s_exists = bpf_core_field_exists(in->s);
  72         if (bpf_core_field_exists(in->s))
  73                 out->s_value = BPF_CORE_READ(in, s.x);
  74         else
  75                 out->s_value = 0xff000005u;
  76
  77         return 0;
  78 }
  79