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/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2018 Facebook */
#ifndef _LINUX_BTF_H
#define _LINUX_BTF_H 1
#include <linux/types.h>
#include <linux/bpfptr.h>
#include <uapi/linux/btf.h>
#include <uapi/linux/bpf.h>
#define BTF_TYPE_EMIT(type) ((void)(type *)0)
#define BTF_TYPE_EMIT_ENUM(enum_val) ((void)enum_val)
enum btf_kfunc_type {
BTF_KFUNC_TYPE_CHECK,
BTF_KFUNC_TYPE_ACQUIRE,
BTF_KFUNC_TYPE_RELEASE,
BTF_KFUNC_TYPE_RET_NULL,
BTF_KFUNC_TYPE_KPTR_ACQUIRE,
BTF_KFUNC_TYPE_MAX,
};
struct btf;
struct btf_member;
struct btf_type;
union bpf_attr;
struct btf_show;
struct btf_id_set;
struct btf_kfunc_id_set {
struct module *owner;
union {
struct {
struct btf_id_set *check_set;
struct btf_id_set *acquire_set;
struct btf_id_set *release_set;
struct btf_id_set *ret_null_set;
struct btf_id_set *kptr_acquire_set;
};
struct btf_id_set *sets[BTF_KFUNC_TYPE_MAX];
};
};
struct btf_id_dtor_kfunc {
u32 btf_id;
u32 kfunc_btf_id;
};
typedef void (*btf_dtor_kfunc_t)(void *);
extern const struct file_operations btf_fops;
void btf_get(struct btf *btf);
void btf_put(struct btf *btf);
int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr);
struct btf *btf_get_by_fd(int fd);
int btf_get_info_by_fd(const struct btf *btf,
const union bpf_attr *attr,
union bpf_attr __user *uattr);
/* Figure out the size of a type_id. If type_id is a modifier
* (e.g. const), it will be resolved to find out the type with size.
*
* For example:
* In describing "const void *", type_id is "const" and "const"
* refers to "void *". The return type will be "void *".
*
* If type_id is a simple "int", then return type will be "int".
*
* @btf: struct btf object
* @type_id: Find out the size of type_id. The type_id of the return
* type is set to *type_id.
* @ret_size: It can be NULL. If not NULL, the size of the return
* type is set to *ret_size.
* Return: The btf_type (resolved to another type with size info if needed).
* NULL is returned if type_id itself does not have size info
* (e.g. void) or it cannot be resolved to another type that
* has size info.
* *type_id and *ret_size will not be changed in the
* NULL return case.
*/
const struct btf_type *btf_type_id_size(const struct btf *btf,
u32 *type_id,
u32 *ret_size);
/*
* Options to control show behaviour.
* - BTF_SHOW_COMPACT: no formatting around type information
* - BTF_SHOW_NONAME: no struct/union member names/types
* - BTF_SHOW_PTR_RAW: show raw (unobfuscated) pointer values;
* equivalent to %px.
* - BTF_SHOW_ZERO: show zero-valued struct/union members; they
* are not displayed by default
* - BTF_SHOW_UNSAFE: skip use of bpf_probe_read() to safely read
* data before displaying it.
*/
#define BTF_SHOW_COMPACT BTF_F_COMPACT
#define BTF_SHOW_NONAME BTF_F_NONAME
#define BTF_SHOW_PTR_RAW BTF_F_PTR_RAW
#define BTF_SHOW_ZERO BTF_F_ZERO
#define BTF_SHOW_UNSAFE (1ULL << 4)
void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj,
struct seq_file *m);
int btf_type_seq_show_flags(const struct btf *btf, u32 type_id, void *obj,
struct seq_file *m, u64 flags);
/*
* Copy len bytes of string representation of obj of BTF type_id into buf.
*
* @btf: struct btf object
* @type_id: type id of type obj points to
* @obj: pointer to typed data
* @buf: buffer to write to
* @len: maximum length to write to buf
* @flags: show options (see above)
*
* Return: length that would have been/was copied as per snprintf, or
* negative error.
*/
int btf_type_snprintf_show(const struct btf *btf, u32 type_id, void *obj,
char *buf, int len, u64 flags);
int btf_get_fd_by_id(u32 id);
u32 btf_obj_id(const struct btf *btf);
bool btf_is_kernel(const struct btf *btf);
bool btf_is_module(const struct btf *btf);
struct module *btf_try_get_module(const struct btf *btf);
u32 btf_nr_types(const struct btf *btf);
bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
const struct btf_member *m,
u32 expected_offset, u32 expected_size);
int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t);
int btf_find_timer(const struct btf *btf, const struct btf_type *t);
struct bpf_map_value_off *btf_parse_kptrs(const struct btf *btf,
const struct btf_type *t);
bool btf_type_is_void(const struct btf_type *t);
s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind);
const struct btf_type *btf_type_skip_modifiers(const struct btf *btf,
u32 id, u32 *res_id);
const struct btf_type *btf_type_resolve_ptr(const struct btf *btf,
u32 id, u32 *res_id);
const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf,
u32 id, u32 *res_id);
const struct btf_type *
btf_resolve_size(const struct btf *btf, const struct btf_type *type,
u32 *type_size);
const char *btf_type_str(const struct btf_type *t);
#define for_each_member(i, struct_type, member) \
for (i = 0, member = btf_type_member(struct_type); \
i < btf_type_vlen(struct_type); \
i++, member++)
#define for_each_vsi(i, datasec_type, member) \
for (i = 0, member = btf_type_var_secinfo(datasec_type); \
i < btf_type_vlen(datasec_type); \
i++, member++)
static inline bool btf_type_is_ptr(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_PTR;
}
static inline bool btf_type_is_int(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_INT;
}
static inline bool btf_type_is_small_int(const struct btf_type *t)
{
return btf_type_is_int(t) && t->size <= sizeof(u64);
}
static inline bool btf_type_is_enum(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM;
}
static inline bool str_is_empty(const char *s)
{
return !s || !s[0];
}
static inline u16 btf_kind(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info);
}
static inline bool btf_is_enum(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_ENUM;
}
static inline bool btf_is_composite(const struct btf_type *t)
{
u16 kind = btf_kind(t);
return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
}
static inline bool btf_is_array(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_ARRAY;
}
static inline bool btf_is_int(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_INT;
}
static inline bool btf_is_ptr(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_PTR;
}
static inline u8 btf_int_offset(const struct btf_type *t)
{
return BTF_INT_OFFSET(*(u32 *)(t + 1));
}
static inline u8 btf_int_encoding(const struct btf_type *t)
{
return BTF_INT_ENCODING(*(u32 *)(t + 1));
}
static inline bool btf_type_is_scalar(const struct btf_type *t)
{
return btf_type_is_int(t) || btf_type_is_enum(t);
}
static inline bool btf_type_is_typedef(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF;
}
static inline bool btf_type_is_func(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC;
}
static inline bool btf_type_is_func_proto(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO;
}
static inline bool btf_type_is_var(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_VAR;
}
static inline bool btf_type_is_type_tag(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_TYPE_TAG;
}
/* union is only a special case of struct:
* all its offsetof(member) == 0
*/
static inline bool btf_type_is_struct(const struct btf_type *t)
{
u8 kind = BTF_INFO_KIND(t->info);
return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
}
static inline u16 btf_type_vlen(const struct btf_type *t)
{
return BTF_INFO_VLEN(t->info);
}
static inline u16 btf_vlen(const struct btf_type *t)
{
return btf_type_vlen(t);
}
static inline u16 btf_func_linkage(const struct btf_type *t)
{
return BTF_INFO_VLEN(t->info);
}
static inline bool btf_type_kflag(const struct btf_type *t)
{
return BTF_INFO_KFLAG(t->info);
}
static inline u32 __btf_member_bit_offset(const struct btf_type *struct_type,
const struct btf_member *member)
{
return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset)
: member->offset;
}
static inline u32 __btf_member_bitfield_size(const struct btf_type *struct_type,
const struct btf_member *member)
{
return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset)
: 0;
}
static inline struct btf_member *btf_members(const struct btf_type *t)
{
return (struct btf_member *)(t + 1);
}
static inline u32 btf_member_bit_offset(const struct btf_type *t, u32 member_idx)
{
const struct btf_member *m = btf_members(t) + member_idx;
return __btf_member_bit_offset(t, m);
}
static inline u32 btf_member_bitfield_size(const struct btf_type *t, u32 member_idx)
{
const struct btf_member *m = btf_members(t) + member_idx;
return __btf_member_bitfield_size(t, m);
}
static inline const struct btf_member *btf_type_member(const struct btf_type *t)
{
return (const struct btf_member *)(t + 1);
}
static inline struct btf_array *btf_array(const struct btf_type *t)
{
return (struct btf_array *)(t + 1);
}
static inline struct btf_enum *btf_enum(const struct btf_type *t)
{
return (struct btf_enum *)(t + 1);
}
static inline const struct btf_var_secinfo *btf_type_var_secinfo(
const struct btf_type *t)
{
return (const struct btf_var_secinfo *)(t + 1);
}
static inline struct btf_param *btf_params(const struct btf_type *t)
{
return (struct btf_param *)(t + 1);
}
#ifdef CONFIG_BPF_SYSCALL
struct bpf_prog;
const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id);
const char *btf_name_by_offset(const struct btf *btf, u32 offset);
struct btf *btf_parse_vmlinux(void);
struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog);
bool btf_kfunc_id_set_contains(const struct btf *btf,
enum bpf_prog_type prog_type,
enum btf_kfunc_type type, u32 kfunc_btf_id);
int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
const struct btf_kfunc_id_set *s);
s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id);
int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_cnt,
struct module *owner);
#else
static inline const struct btf_type *btf_type_by_id(const struct btf *btf,
u32 type_id)
{
return NULL;
}
static inline const char *btf_name_by_offset(const struct btf *btf,
u32 offset)
{
return NULL;
}
static inline bool btf_kfunc_id_set_contains(const struct btf *btf,
enum bpf_prog_type prog_type,
enum btf_kfunc_type type,
u32 kfunc_btf_id)
{
return false;
}
static inline int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,
const struct btf_kfunc_id_set *s)
{
return 0;
}
static inline s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id)
{
return -ENOENT;
}
static inline int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors,
u32 add_cnt, struct module *owner)
{
return 0;
}
#endif
#endif
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