test_core_reloc_bitfields_direct.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
 9char _license[] SEC("license") = "GPL";
10
11struct {
12	char in[256];
13	char out[256];
14} data = {};
15
16struct core_reloc_bitfields {
17	/* unsigned bitfields */
18	uint8_t		ub1: 1;
19	uint8_t		ub2: 2;
20	uint32_t	ub7: 7;
21	/* signed bitfields */
22	int8_t		sb4: 4;
23	int32_t		sb20: 20;
24	/* non-bitfields */
25	uint32_t	u32;
26	int32_t		s32;
27};
28
29/* bitfield read results, all as plain integers */
30struct core_reloc_bitfields_output {
31	int64_t		ub1;
32	int64_t		ub2;
33	int64_t		ub7;
34	int64_t		sb4;
35	int64_t		sb20;
36	int64_t		u32;
37	int64_t		s32;
38};
39
40struct pt_regs;
41
42struct trace_sys_enter {
43	struct pt_regs *regs;
44	long id;
45};
46
47SEC("tp_btf/sys_enter")
48int test_core_bitfields_direct(void *ctx)
49{
50	struct core_reloc_bitfields *in = (void *)&data.in;
51	struct core_reloc_bitfields_output *out = (void *)&data.out;
52
53	out->ub1 = BPF_CORE_READ_BITFIELD(in, ub1);
54	out->ub2 = BPF_CORE_READ_BITFIELD(in, ub2);
55	out->ub7 = BPF_CORE_READ_BITFIELD(in, ub7);
56	out->sb4 = BPF_CORE_READ_BITFIELD(in, sb4);
57	out->sb20 = BPF_CORE_READ_BITFIELD(in, sb20);
58	out->u32 = BPF_CORE_READ_BITFIELD(in, u32);
59	out->s32 = BPF_CORE_READ_BITFIELD(in, s32);
60
61	return 0;
62}
63