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/* This file excercises the ELF loader.
*/
#include "common.h"
char __license[] __section("license") = "MIT";
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__type(key, uint32_t);
__type(value, uint64_t);
__uint(max_entries, 1);
__uint(map_flags, BPF_F_NO_PREALLOC);
} hash_map __section(".maps");
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(key_size, sizeof(uint32_t));
__uint(value_size, sizeof(uint64_t));
__uint(max_entries, 2);
} hash_map2 __section(".maps");
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__type(key, uint32_t);
__type(value, uint64_t);
__uint(max_entries, 1);
__uint(pinning, 1 /* LIBBPF_PIN_BY_NAME */);
} btf_pin __section(".maps");
// Named map type definition, without structure variable declaration.
struct inner_map_t {
__uint(type, BPF_MAP_TYPE_HASH);
__type(key, uint32_t);
__type(value, int);
__uint(max_entries, 1);
};
// Anonymous map type definition with structure variable declaration.
struct {
__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
__uint(key_size, sizeof(uint32_t));
__uint(max_entries, 1);
__array(values, struct inner_map_t);
} btf_outer_map __section(".maps");
// Array of maps with anonymous inner struct.
struct {
__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
__uint(key_size, sizeof(uint32_t));
__uint(max_entries, 1);
__array(
values, struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
__type(key, uint32_t);
__type(value, uint32_t);
});
} btf_outer_map_anon __section(".maps");
struct perf_event {
uint64_t foo;
uint64_t bar;
};
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(max_entries, 4096);
__type(value, struct perf_event);
} perf_event_array __section(".maps");
struct bpf_map_def array_of_hash_map __section("maps") = {
.type = BPF_MAP_TYPE_ARRAY_OF_MAPS,
.key_size = sizeof(uint32_t),
.max_entries = 2,
};
typedef struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(key_size, sizeof(uint32_t));
__uint(value_size, sizeof(uint64_t));
__uint(max_entries, 1);
} array_map_t;
// Map definition behind a typedef.
array_map_t btf_typedef_map __section(".maps");
static int __attribute__((noinline)) __section("static") static_fn(uint32_t arg) {
return arg - 1;
}
int __attribute__((noinline)) global_fn2(uint32_t arg) {
return arg + 2;
}
int __attribute__((noinline)) __section("other") global_fn3(uint32_t arg) {
return arg + 1;
}
int __attribute__((noinline)) global_fn(uint32_t arg) {
return static_fn(arg) + global_fn2(arg) + global_fn3(arg);
}
volatile unsigned int key1 = 0; // .bss
volatile unsigned int key2 = 1; // .data
volatile const unsigned int key3 = 2; // .rodata
// .rodata, populated by loader
volatile const uint32_t arg;
// custom .rodata section, populated by loader
volatile const uint32_t arg2 __section(".rodata.test");
// custom .data section
volatile uint32_t arg3 __section(".data.test");
__section("xdp") int xdp_prog() {
bpf_map_lookup_elem(&hash_map, (void *)&key1);
bpf_map_lookup_elem(&hash_map2, (void *)&key2);
bpf_map_lookup_elem(&hash_map2, (void *)&key3);
return static_fn(arg) + global_fn(arg) + arg2 + arg3;
}
// This function has no relocations, and is thus parsed differently.
__section("socket") int no_relocation() {
return 0;
}
// Make sure we allow relocations generated by inline assembly.
__section("socket/2") int asm_relocation() {
int my_const;
asm("%0 = MY_CONST ll" : "=r"(my_const));
return my_const;
}
volatile const unsigned int uneg = -1;
volatile const int neg = -2;
static volatile const unsigned int static_uneg = -3;
static volatile const int static_neg = -4;
__section("socket/3") int data_sections() {
if (uneg != (unsigned int)-1)
return __LINE__;
if (neg != -2)
return __LINE__;
if (static_uneg != (unsigned int)-3)
return __LINE__;
if (static_neg != -4)
return __LINE__;
return 0;
}
/*
* Up until LLVM 14, this program results in an .rodata.cst32 section
* that is accessed by 'return values[i]'. For this section, no BTF is
* emitted. 'values' cannot be rewritten, since there is no BTF info
* describing the data section.
*/
__section("socket/4") int anon_const() {
volatile int ctx = 0;
// 32 bytes wide results in a .rodata.cst32 section.
#define values \
(uint64_t[]) { \
0x0, 0x1, 0x2, 0x3 \
}
int i;
for (i = 0; i < 3; i++) {
if (ctx == values[i]) {
return values[i];
}
}
return 0;
}
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