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1// SPDX-License-Identifier: GPL-2.02#ifndef _XDP_SAMPLE_BPF_H3#define _XDP_SAMPLE_BPF_H4 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 2214#define ENETDOWN 10015#define EMSGSIZE 9016#define EOPNOTSUPP 9517#define ENOSPC 2818 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 = 132};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 below52 * conflicts with vmlinux.h include in BPF files, so we define them here.53 *54 * Following functions are taken from kernel sources and55 * 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 fail59 * under gcc 4.4.60 *61 * Using extra __may_alias__ type to allow aliasing62 * 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 than114 * 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#endif122