/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
/* Copyright (c) 2019 Facebook */
#ifndef __RELO_CORE_H
#define __RELO_CORE_H
#include <linux/bpf.h>
struct bpf_core_cand {
const struct btf *btf;
__u32 id;
};
/* dynamically sized list of type IDs and its associated struct btf */
struct bpf_core_cand_list {
struct bpf_core_cand *cands;
int len;
};
#define BPF_CORE_SPEC_MAX_LEN 64
/* represents BPF CO-RE field or array element accessor */
struct bpf_core_accessor {
__u32 type_id; /* struct/union type or array element type */
__u32 idx; /* field index or array index */
const char *name; /* field name or NULL for array accessor */
};
struct bpf_core_spec {
const struct btf *btf;
/* high-level spec: named fields and array indices only */
struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN];
/* original unresolved (no skip_mods_or_typedefs) root type ID */
__u32 root_type_id;
/* CO-RE relocation kind */
enum bpf_core_relo_kind relo_kind;
/* high-level spec length */
int len;
/* raw, low-level spec: 1-to-1 with accessor spec string */
int raw_spec[BPF_CORE_SPEC_MAX_LEN];
/* raw spec length */
int raw_len;
/* field bit offset represented by spec */
__u32 bit_offset;
};
struct bpf_core_relo_res {
/* expected value in the instruction, unless validate == false */
__u64 orig_val;
/* new value that needs to be patched up to */
__u64 new_val;
/* relocation unsuccessful, poison instruction, but don't fail load */
bool poison;
/* some relocations can't be validated against orig_val */
bool validate;
/* for field byte offset relocations or the forms:
* *(T *)(rX + <off>) = rY
* rX = *(T *)(rY + <off>),
* we remember original and resolved field size to adjust direct
* memory loads of pointers and integers; this is necessary for 32-bit
* host kernel architectures, but also allows to automatically
* relocate fields that were resized from, e.g., u32 to u64, etc.
*/
bool fail_memsz_adjust;
__u32 orig_sz;
__u32 orig_type_id;
__u32 new_sz;
__u32 new_type_id;
};
int __bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
const struct btf *targ_btf, __u32 targ_id, int level);
int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
const struct btf *targ_btf, __u32 targ_id);
int __bpf_core_types_match(const struct btf *local_btf, __u32 local_id, const struct btf *targ_btf,
__u32 targ_id, bool behind_ptr, int level);
int bpf_core_types_match(const struct btf *local_btf, __u32 local_id, const struct btf *targ_btf,
__u32 targ_id);
size_t bpf_core_essential_name_len(const char *name);
int bpf_core_calc_relo_insn(const char *prog_name,
const struct bpf_core_relo *relo, int relo_idx,
const struct btf *local_btf,
struct bpf_core_cand_list *cands,
struct bpf_core_spec *specs_scratch,
struct bpf_core_relo_res *targ_res);
int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
int insn_idx, const struct bpf_core_relo *relo,
int relo_idx, const struct bpf_core_relo_res *res);
int bpf_core_parse_spec(const char *prog_name, const struct btf *btf,
const struct bpf_core_relo *relo,
struct bpf_core_spec *spec);
int bpf_core_format_spec(char *buf, size_t buf_sz, const struct bpf_core_spec *spec);
#endif