1// SPDX-License-Identifier: GPL-2.0
2#ifndef _XDP_SAMPLE_BPF_H
3#define _XDP_SAMPLE_BPF_H
4
5#include "vmlinux.h"
6#include <bpf/bpf_tracing.h>
7#include <bpf/bpf_core_read.h>
8#include <bpf/bpf_helpers.h>
9
10#include "xdp_sample_shared.h"
11
12#define ETH_ALEN 6
13#define ETH_P_802_3_MIN 0x0600
14#define ETH_P_8021Q 0x8100
15#define ETH_P_8021AD 0x88A8
16#define ETH_P_IP 0x0800
17#define ETH_P_IPV6 0x86DD
18#define ETH_P_ARP 0x0806
19#define IPPROTO_ICMPV6 58
20
21#define EINVAL 22
22#define ENETDOWN 100
23#define EMSGSIZE 90
24#define EOPNOTSUPP 95
25#define ENOSPC 28
26
27typedef struct {
28	__uint(type, BPF_MAP_TYPE_ARRAY);
29	__uint(map_flags, BPF_F_MMAPABLE);
30	__type(key, unsigned int);
31	__type(value, struct datarec);
32} array_map;
33
34extern array_map rx_cnt;
35extern const volatile int nr_cpus;
36
37enum {
38	XDP_REDIRECT_SUCCESS = 0,
39	XDP_REDIRECT_ERROR = 1
40};
41
42static __always_inline void swap_src_dst_mac(void *data)
43{
44	unsigned short *p = data;
45	unsigned short dst[3];
46
47	dst[0] = p[0];
48	dst[1] = p[1];
49	dst[2] = p[2];
50	p[0] = p[3];
51	p[1] = p[4];
52	p[2] = p[5];
53	p[3] = dst[0];
54	p[4] = dst[1];
55	p[5] = dst[2];
56}
57
58#if defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && \
59	__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
60#define bpf_ntohs(x)		__builtin_bswap16(x)
61#define bpf_htons(x)		__builtin_bswap16(x)
62#elif defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && \
63	__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
64#define bpf_ntohs(x)		(x)
65#define bpf_htons(x)		(x)
66#else
67# error "Endianness detection needs to be set up for your compiler?!"
68#endif
69
70/*
71 * Note: including linux/compiler.h or linux/kernel.h for the macros below
72 * conflicts with vmlinux.h include in BPF files, so we define them here.
73 *
74 * Following functions are taken from kernel sources and
75 * break aliasing rules in their original form.
76 *
77 * While kernel is compiled with -fno-strict-aliasing,
78 * perf uses -Wstrict-aliasing=3 which makes build fail
79 * under gcc 4.4.
80 *
81 * Using extra __may_alias__ type to allow aliasing
82 * in this case.
83 */
84typedef __u8  __attribute__((__may_alias__))  __u8_alias_t;
85typedef __u16 __attribute__((__may_alias__)) __u16_alias_t;
86typedef __u32 __attribute__((__may_alias__)) __u32_alias_t;
87typedef __u64 __attribute__((__may_alias__)) __u64_alias_t;
88
89static __always_inline void __read_once_size(const volatile void *p, void *res, int size)
90{
91	switch (size) {
92	case 1: *(__u8_alias_t  *) res = *(volatile __u8_alias_t  *) p; break;
93	case 2: *(__u16_alias_t *) res = *(volatile __u16_alias_t *) p; break;
94	case 4: *(__u32_alias_t *) res = *(volatile __u32_alias_t *) p; break;
95	case 8: *(__u64_alias_t *) res = *(volatile __u64_alias_t *) p; break;
96	default:
97		asm volatile ("" : : : "memory");
98		__builtin_memcpy((void *)res, (const void *)p, size);
99		asm volatile ("" : : : "memory");
100	}
101}
102
103static __always_inline void __write_once_size(volatile void *p, void *res, int size)
104{
105	switch (size) {
106	case 1: *(volatile  __u8_alias_t *) p = *(__u8_alias_t  *) res; break;
107	case 2: *(volatile __u16_alias_t *) p = *(__u16_alias_t *) res; break;
108	case 4: *(volatile __u32_alias_t *) p = *(__u32_alias_t *) res; break;
109	case 8: *(volatile __u64_alias_t *) p = *(__u64_alias_t *) res; break;
110	default:
111		asm volatile ("" : : : "memory");
112		__builtin_memcpy((void *)p, (const void *)res, size);
113		asm volatile ("" : : : "memory");
114	}
115}
116
117#define READ_ONCE(x)					\
118({							\
119	union { typeof(x) __val; char __c[1]; } __u =	\
120		{ .__c = { 0 } };			\
121	__read_once_size(&(x), __u.__c, sizeof(x));	\
122	__u.__val;					\
123})
124
125#define WRITE_ONCE(x, val)				\
126({							\
127	union { typeof(x) __val; char __c[1]; } __u =	\
128		{ .__val = (val) }; 			\
129	__write_once_size(&(x), __u.__c, sizeof(x));	\
130	__u.__val;					\
131})
132
133/* Add a value using relaxed read and relaxed write. Less expensive than
134 * fetch_add when there is no write concurrency.
135 */
136#define NO_TEAR_ADD(x, val) WRITE_ONCE((x), READ_ONCE(x) + (val))
137#define NO_TEAR_INC(x) NO_TEAR_ADD((x), 1)
138
139#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
140
141#endif
142