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 10 struct s { 11 int a; 12 long long b; 13 } __attribute__((packed)); 14 15 /* .data section */ 16 int in1 = -1; 17 long long in2 = -1; 18 19 /* .bss section */ 20 char in3 = '\0'; 21 long long in4 __attribute__((aligned(64))) = 0; 22 struct s in5 = {}; 23 24 /* .rodata section */ 25 const volatile struct { 26 const int in6; 27 } in = {}; 28 29 /* .data section */ 30 int out1 = -1; 31 long long out2 = -1; 32 33 /* .bss section */ 34 char out3 = 0; 35 long long out4 = 0; 36 int out6 = 0; 37 38 extern bool CONFIG_BPF_SYSCALL __kconfig; 39 extern int LINUX_KERNEL_VERSION __kconfig; 40 bool bpf_syscall = 0; 41 int kern_ver = 0; 42 43 struct s out5 = {}; 44 45 46 const volatile int in_dynarr_sz SEC(".rodata.dyn"); 47 const volatile int in_dynarr[4] SEC(".rodata.dyn") = { -1, -2, -3, -4 }; 48 49 int out_dynarr[4] SEC(".data.dyn") = { 1, 2, 3, 4 }; 50 51 int read_mostly_var __read_mostly; 52 int out_mostly_var; 53 54 char huge_arr[16 * 1024 * 1024]; 55 56 /* non-mmapable custom .data section */ 57 58 struct my_value { int x, y, z; }; 59 60 __hidden int zero_key SEC(".data.non_mmapable"); 61 static struct my_value zero_value SEC(".data.non_mmapable"); 62 63 struct { 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 70 SEC("raw_tp/sys_enter") 71 int 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 98 char _license[] SEC("license") = "GPL"; 99