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 "net_shared.h"
11#include "xdp_sample_shared.h"
12
13#define EINVAL 22
14#define ENETDOWN 100
15#define EMSGSIZE 90
16#define EOPNOTSUPP 95
17#define ENOSPC 28
18
19typedef struct {
20 __uint(type, BPF_MAP_TYPE_ARRAY);
21 __uint(map_flags, BPF_F_MMAPABLE);
22 __type(key, unsigned int);
23 __type(value, struct datarec);
24} array_map;
25
26extern array_map rx_cnt;
27extern const volatile int nr_cpus;
28
29enum {
30 XDP_REDIRECT_SUCCESS = 0,
31 XDP_REDIRECT_ERROR = 1
32};
33
34static __always_inline void swap_src_dst_mac(void *data)
35{
36 unsigned short *p = data;
37 unsigned short dst[3];
38
39 dst[0] = p[0];
40 dst[1] = p[1];
41 dst[2] = p[2];
42 p[0] = p[3];
43 p[1] = p[4];
44 p[2] = p[5];
45 p[3] = dst[0];
46 p[4] = dst[1];
47 p[5] = dst[2];
48}
49
50/*
51 * Note: including linux/compiler.h or linux/kernel.h for the macros below
52 * conflicts with vmlinux.h include in BPF files, so we define them here.
53 *
54 * Following functions are taken from kernel sources and
55 * break aliasing rules in their original form.
56 *
57 * While kernel is compiled with -fno-strict-aliasing,
58 * perf uses -Wstrict-aliasing=3 which makes build fail
59 * under gcc 4.4.
60 *
61 * Using extra __may_alias__ type to allow aliasing
62 * in this case.
63 */
64typedef __u8 __attribute__((__may_alias__)) __u8_alias_t;
65typedef __u16 __attribute__((__may_alias__)) __u16_alias_t;
66typedef __u32 __attribute__((__may_alias__)) __u32_alias_t;
67typedef __u64 __attribute__((__may_alias__)) __u64_alias_t;
68
69static __always_inline void __read_once_size(const volatile void *p, void *res, int size)
70{
71 switch (size) {
72 case 1: *(__u8_alias_t *) res = *(volatile __u8_alias_t *) p; break;
73 case 2: *(__u16_alias_t *) res = *(volatile __u16_alias_t *) p; break;
74 case 4: *(__u32_alias_t *) res = *(volatile __u32_alias_t *) p; break;
75 case 8: *(__u64_alias_t *) res = *(volatile __u64_alias_t *) p; break;
76 default:
77 asm volatile ("" : : : "memory");
78 __builtin_memcpy((void *)res, (const void *)p, size);
79 asm volatile ("" : : : "memory");
80 }
81}
82
83static __always_inline void __write_once_size(volatile void *p, void *res, int size)
84{
85 switch (size) {
86 case 1: *(volatile __u8_alias_t *) p = *(__u8_alias_t *) res; break;
87 case 2: *(volatile __u16_alias_t *) p = *(__u16_alias_t *) res; break;
88 case 4: *(volatile __u32_alias_t *) p = *(__u32_alias_t *) res; break;
89 case 8: *(volatile __u64_alias_t *) p = *(__u64_alias_t *) res; break;
90 default:
91 asm volatile ("" : : : "memory");
92 __builtin_memcpy((void *)p, (const void *)res, size);
93 asm volatile ("" : : : "memory");
94 }
95}
96
97#define READ_ONCE(x) \
98({ \
99 union { typeof(x) __val; char __c[1]; } __u = \
100 { .__c = { 0 } }; \
101 __read_once_size(&(x), __u.__c, sizeof(x)); \
102 __u.__val; \
103})
104
105#define WRITE_ONCE(x, val) \
106({ \
107 union { typeof(x) __val; char __c[1]; } __u = \
108 { .__val = (val) }; \
109 __write_once_size(&(x), __u.__c, sizeof(x)); \
110 __u.__val; \
111})
112
113/* Add a value using relaxed read and relaxed write. Less expensive than
114 * fetch_add when there is no write concurrency.
115 */
116#define NO_TEAR_ADD(x, val) WRITE_ONCE((x), READ_ONCE(x) + (val))
117#define NO_TEAR_INC(x) NO_TEAR_ADD((x), 1)
118
119#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
120
121#endif
122

source code of linux/samples/bpf/xdp_sample.bpf.h