1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) 2018 Facebook */
7 #include <linux/types.h>
8 #include <uapi/linux/btf.h>
9 #include <uapi/linux/bpf.h>
11 #define BTF_TYPE_EMIT(type) ((void)(type *)0)
19 extern const struct file_operations btf_fops;
21 void btf_get(struct btf *btf);
22 void btf_put(struct btf *btf);
23 int btf_new_fd(const union bpf_attr *attr);
24 struct btf *btf_get_by_fd(int fd);
25 int btf_get_info_by_fd(const struct btf *btf,
26 const union bpf_attr *attr,
27 union bpf_attr __user *uattr);
28 /* Figure out the size of a type_id. If type_id is a modifier
29 * (e.g. const), it will be resolved to find out the type with size.
32 * In describing "const void *", type_id is "const" and "const"
33 * refers to "void *". The return type will be "void *".
35 * If type_id is a simple "int", then return type will be "int".
37 * @btf: struct btf object
38 * @type_id: Find out the size of type_id. The type_id of the return
39 * type is set to *type_id.
40 * @ret_size: It can be NULL. If not NULL, the size of the return
41 * type is set to *ret_size.
42 * Return: The btf_type (resolved to another type with size info if needed).
43 * NULL is returned if type_id itself does not have size info
44 * (e.g. void) or it cannot be resolved to another type that
46 * *type_id and *ret_size will not be changed in the
49 const struct btf_type *btf_type_id_size(const struct btf *btf,
54 * Options to control show behaviour.
55 * - BTF_SHOW_COMPACT: no formatting around type information
56 * - BTF_SHOW_NONAME: no struct/union member names/types
57 * - BTF_SHOW_PTR_RAW: show raw (unobfuscated) pointer values;
59 * - BTF_SHOW_ZERO: show zero-valued struct/union members; they
60 * are not displayed by default
61 * - BTF_SHOW_UNSAFE: skip use of bpf_probe_read() to safely read
62 * data before displaying it.
64 #define BTF_SHOW_COMPACT BTF_F_COMPACT
65 #define BTF_SHOW_NONAME BTF_F_NONAME
66 #define BTF_SHOW_PTR_RAW BTF_F_PTR_RAW
67 #define BTF_SHOW_ZERO BTF_F_ZERO
68 #define BTF_SHOW_UNSAFE (1ULL << 4)
70 void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj,
72 int btf_type_seq_show_flags(const struct btf *btf, u32 type_id, void *obj,
73 struct seq_file *m, u64 flags);
76 * Copy len bytes of string representation of obj of BTF type_id into buf.
78 * @btf: struct btf object
79 * @type_id: type id of type obj points to
80 * @obj: pointer to typed data
81 * @buf: buffer to write to
82 * @len: maximum length to write to buf
83 * @flags: show options (see above)
85 * Return: length that would have been/was copied as per snprintf, or
88 int btf_type_snprintf_show(const struct btf *btf, u32 type_id, void *obj,
89 char *buf, int len, u64 flags);
91 int btf_get_fd_by_id(u32 id);
92 u32 btf_obj_id(const struct btf *btf);
93 bool btf_is_kernel(const struct btf *btf);
94 bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
95 const struct btf_member *m,
96 u32 expected_offset, u32 expected_size);
97 int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t);
98 bool btf_type_is_void(const struct btf_type *t);
99 s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind);
100 const struct btf_type *btf_type_skip_modifiers(const struct btf *btf,
101 u32 id, u32 *res_id);
102 const struct btf_type *btf_type_resolve_ptr(const struct btf *btf,
103 u32 id, u32 *res_id);
104 const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf,
105 u32 id, u32 *res_id);
106 const struct btf_type *
107 btf_resolve_size(const struct btf *btf, const struct btf_type *type,
110 #define for_each_member(i, struct_type, member) \
111 for (i = 0, member = btf_type_member(struct_type); \
112 i < btf_type_vlen(struct_type); \
115 #define for_each_vsi(i, datasec_type, member) \
116 for (i = 0, member = btf_type_var_secinfo(datasec_type); \
117 i < btf_type_vlen(datasec_type); \
120 static inline bool btf_type_is_ptr(const struct btf_type *t)
122 return BTF_INFO_KIND(t->info) == BTF_KIND_PTR;
125 static inline bool btf_type_is_int(const struct btf_type *t)
127 return BTF_INFO_KIND(t->info) == BTF_KIND_INT;
130 static inline bool btf_type_is_small_int(const struct btf_type *t)
132 return btf_type_is_int(t) && t->size <= sizeof(u64);
135 static inline bool btf_type_is_enum(const struct btf_type *t)
137 return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM;
140 static inline bool btf_type_is_typedef(const struct btf_type *t)
142 return BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF;
145 static inline bool btf_type_is_func(const struct btf_type *t)
147 return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC;
150 static inline bool btf_type_is_func_proto(const struct btf_type *t)
152 return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO;
155 static inline bool btf_type_is_var(const struct btf_type *t)
157 return BTF_INFO_KIND(t->info) == BTF_KIND_VAR;
160 /* union is only a special case of struct:
161 * all its offsetof(member) == 0
163 static inline bool btf_type_is_struct(const struct btf_type *t)
165 u8 kind = BTF_INFO_KIND(t->info);
167 return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
170 static inline u16 btf_type_vlen(const struct btf_type *t)
172 return BTF_INFO_VLEN(t->info);
175 static inline u16 btf_func_linkage(const struct btf_type *t)
177 return BTF_INFO_VLEN(t->info);
180 static inline bool btf_type_kflag(const struct btf_type *t)
182 return BTF_INFO_KFLAG(t->info);
185 static inline u32 btf_member_bit_offset(const struct btf_type *struct_type,
186 const struct btf_member *member)
188 return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset)
192 static inline u32 btf_member_bitfield_size(const struct btf_type *struct_type,
193 const struct btf_member *member)
195 return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset)
199 static inline const struct btf_member *btf_type_member(const struct btf_type *t)
201 return (const struct btf_member *)(t + 1);
204 static inline const struct btf_var_secinfo *btf_type_var_secinfo(
205 const struct btf_type *t)
207 return (const struct btf_var_secinfo *)(t + 1);
210 #ifdef CONFIG_BPF_SYSCALL
213 const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id);
214 const char *btf_name_by_offset(const struct btf *btf, u32 offset);
215 struct btf *btf_parse_vmlinux(void);
216 struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog);
218 static inline const struct btf_type *btf_type_by_id(const struct btf *btf,
223 static inline const char *btf_name_by_offset(const struct btf *btf,