1// SPDX-License-Identifier: GPL-2.0 2/* Copyright (c) 2019 Facebook */ 3 4#include <stdbool.h> 5#include <linux/bpf.h> 6#include <bpf/bpf_helpers.h> 7 8#define __read_mostly SEC(".data.read_mostly") 9 10struct s { 11 int a; 12 long long b; 13} __attribute__((packed)); 14 15/* .data section */ 16int in1 = -1; 17long long in2 = -1; 18 19/* .bss section */ 20char in3 = '\0'; 21long long in4 __attribute__((aligned(64))) = 0; 22struct s in5 = {}; 23 24/* .rodata section */ 25const volatile struct { 26 const int in6; 27} in = {}; 28 29/* .data section */ 30int out1 = -1; 31long long out2 = -1; 32 33/* .bss section */ 34char out3 = 0; 35long long out4 = 0; 36int out6 = 0; 37 38extern bool CONFIG_BPF_SYSCALL __kconfig; 39extern int LINUX_KERNEL_VERSION __kconfig; 40bool bpf_syscall = 0; 41int kern_ver = 0; 42 43struct s out5 = {}; 44 45 46const volatile int in_dynarr_sz SEC(".rodata.dyn"); 47const volatile int in_dynarr[4] SEC(".rodata.dyn") = { -1, -2, -3, -4 }; 48 49int out_dynarr[4] SEC(".data.dyn") = { 1, 2, 3, 4 }; 50 51int read_mostly_var __read_mostly; 52int out_mostly_var; 53 54char huge_arr[16 * 1024 * 1024]; 55 56/* non-mmapable custom .data section */ 57 58struct my_value { int x, y, z; }; 59 60__hidden int zero_key SEC(".data.non_mmapable"); 61static struct my_value zero_value SEC(".data.non_mmapable"); 62 63struct { 64 __uint(type, BPF_MAP_TYPE_ARRAY); 65 __type(key, int); 66 __type(value, struct my_value); 67 __uint(max_entries, 1); 68} my_map SEC(".maps"); 69 70SEC("raw_tp/sys_enter") 71int handler(const void *ctx) 72{ 73 int i; 74 75 out1 = in1; 76 out2 = in2; 77 out3 = in3; 78 out4 = in4; 79 out5 = in5; 80 out6 = in.in6; 81 82 bpf_syscall = CONFIG_BPF_SYSCALL; 83 kern_ver = LINUX_KERNEL_VERSION; 84 85 for (i = 0; i < in_dynarr_sz; i++) 86 out_dynarr[i] = in_dynarr[i]; 87 88 out_mostly_var = read_mostly_var; 89 90 huge_arr[sizeof(huge_arr) - 1] = 123; 91 92 /* make sure zero_key and zero_value are not optimized out */ 93 bpf_map_update_elem(&my_map, &zero_key, &zero_value, BPF_ANY); 94 95 return 0; 96} 97 98char _license[] SEC("license") = "GPL"; 99