1// SPDX-License-Identifier: GPL-2.0
  2
  3#include <linux/bpf.h>
  4#include <stdint.h>
  5
  6#include <bpf/bpf_helpers.h>
  7#include <bpf/bpf_core_read.h>
  8
  9#include "bpf_misc.h"
 10
 11struct core_reloc_bitfields {
 12	/* unsigned bitfields */
 13	uint8_t		ub1: 1;
 14	uint8_t		ub2: 2;
 15	uint32_t	ub7: 7;
 16	/* signed bitfields */
 17	int8_t		sb4: 4;
 18	int32_t		sb20: 20;
 19	/* non-bitfields */
 20	uint32_t	u32;
 21	int32_t		s32;
 22} __attribute__((preserve_access_index));
 23
 24SEC("tc")
 25__description("single CO-RE bitfield roundtrip")
 26__btf_path("btf__core_reloc_bitfields.bpf.o")
 27__success
 28__retval(3)
 29int single_field_roundtrip(struct __sk_buff *ctx)
 30{
 31	struct core_reloc_bitfields bitfields;
 32
 33	__builtin_memset(&bitfields, 0, sizeof(bitfields));
 34	BPF_CORE_WRITE_BITFIELD(&bitfields, ub2, 3);
 35	return BPF_CORE_READ_BITFIELD(&bitfields, ub2);
 36}
 37
 38SEC("tc")
 39__description("multiple CO-RE bitfield roundtrip")
 40__btf_path("btf__core_reloc_bitfields.bpf.o")
 41__success
 42__retval(0x3FD)
 43int multiple_field_roundtrip(struct __sk_buff *ctx)
 44{
 45	struct core_reloc_bitfields bitfields;
 46	uint8_t ub2;
 47	int8_t sb4;
 48
 49	__builtin_memset(&bitfields, 0, sizeof(bitfields));
 50	BPF_CORE_WRITE_BITFIELD(&bitfields, ub2, 1);
 51	BPF_CORE_WRITE_BITFIELD(&bitfields, sb4, -1);
 52
 53	ub2 = BPF_CORE_READ_BITFIELD(&bitfields, ub2);
 54	sb4 = BPF_CORE_READ_BITFIELD(&bitfields, sb4);
 55
 56	return (((uint8_t)sb4) << 2) | ub2;
 57}
 58
 59SEC("tc")
 60__description("adjacent CO-RE bitfield roundtrip")
 61__btf_path("btf__core_reloc_bitfields.bpf.o")
 62__success
 63__retval(7)
 64int adjacent_field_roundtrip(struct __sk_buff *ctx)
 65{
 66	struct core_reloc_bitfields bitfields;
 67	uint8_t ub1, ub2;
 68
 69	__builtin_memset(&bitfields, 0, sizeof(bitfields));
 70	BPF_CORE_WRITE_BITFIELD(&bitfields, ub1, 1);
 71	BPF_CORE_WRITE_BITFIELD(&bitfields, ub2, 3);
 72
 73	ub1 = BPF_CORE_READ_BITFIELD(&bitfields, ub1);
 74	ub2 = BPF_CORE_READ_BITFIELD(&bitfields, ub2);
 75
 76	return (ub2 << 1) | ub1;
 77}
 78
 79SEC("tc")
 80__description("multibyte CO-RE bitfield roundtrip")
 81__btf_path("btf__core_reloc_bitfields.bpf.o")
 82__success
 83__retval(0x21)
 84int multibyte_field_roundtrip(struct __sk_buff *ctx)
 85{
 86	struct core_reloc_bitfields bitfields;
 87	uint32_t ub7;
 88	uint8_t ub1;
 89
 90	__builtin_memset(&bitfields, 0, sizeof(bitfields));
 91	BPF_CORE_WRITE_BITFIELD(&bitfields, ub1, 1);
 92	BPF_CORE_WRITE_BITFIELD(&bitfields, ub7, 16);
 93
 94	ub1 = BPF_CORE_READ_BITFIELD(&bitfields, ub1);
 95	ub7 = BPF_CORE_READ_BITFIELD(&bitfields, ub7);
 96
 97	return (ub7 << 1) | ub1;
 98}
 99
100char _license[] SEC("license") = "GPL";