162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */
262306a36Sopenharmony_ci/*
362306a36Sopenharmony_ci * Copyright (C) 2015, He Kuang <hekuang@huawei.com>
462306a36Sopenharmony_ci * Copyright (C) 2015, Huawei Inc.
562306a36Sopenharmony_ci */
662306a36Sopenharmony_ci#ifndef __BPF_PROLOGUE_H
762306a36Sopenharmony_ci#define __BPF_PROLOGUE_H
862306a36Sopenharmony_ci
962306a36Sopenharmony_cistruct probe_trace_arg;
1062306a36Sopenharmony_cistruct bpf_insn;
1162306a36Sopenharmony_ci
1262306a36Sopenharmony_ci#define BPF_PROLOGUE_MAX_ARGS 3
1362306a36Sopenharmony_ci#define BPF_PROLOGUE_START_ARG_REG BPF_REG_3
1462306a36Sopenharmony_ci#define BPF_PROLOGUE_FETCH_RESULT_REG BPF_REG_2
1562306a36Sopenharmony_ci
1662306a36Sopenharmony_ci#ifdef HAVE_BPF_PROLOGUE
1762306a36Sopenharmony_ciint bpf__gen_prologue(struct probe_trace_arg *args, int nargs,
1862306a36Sopenharmony_ci		      struct bpf_insn *new_prog, size_t *new_cnt,
1962306a36Sopenharmony_ci		      size_t cnt_space);
2062306a36Sopenharmony_ci#else
2162306a36Sopenharmony_ci#include <linux/compiler.h>
2262306a36Sopenharmony_ci#include <errno.h>
2362306a36Sopenharmony_ci
2462306a36Sopenharmony_cistatic inline int
2562306a36Sopenharmony_cibpf__gen_prologue(struct probe_trace_arg *args __maybe_unused,
2662306a36Sopenharmony_ci		  int nargs __maybe_unused,
2762306a36Sopenharmony_ci		  struct bpf_insn *new_prog __maybe_unused,
2862306a36Sopenharmony_ci		  size_t *new_cnt,
2962306a36Sopenharmony_ci		  size_t cnt_space __maybe_unused)
3062306a36Sopenharmony_ci{
3162306a36Sopenharmony_ci	if (!new_cnt)
3262306a36Sopenharmony_ci		return -EINVAL;
3362306a36Sopenharmony_ci	*new_cnt = 0;
3462306a36Sopenharmony_ci	return -ENOTSUP;
3562306a36Sopenharmony_ci}
3662306a36Sopenharmony_ci#endif
3762306a36Sopenharmony_ci#endif /* __BPF_PROLOGUE_H */
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