1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Copyright (c) 2018 Facebook */ 3 4 #ifndef _LINUX_BTF_H 5 #define _LINUX_BTF_H 1 6 7 #include <linux/types.h> 8 #include <uapi/linux/btf.h> 9 10 struct btf; 11 struct btf_member; 12 struct btf_type; 13 union bpf_attr; 14 15 extern const struct file_operations btf_fops; 16 17 void btf_put(struct btf *btf); 18 int btf_new_fd(const union bpf_attr *attr); 19 struct btf *btf_get_by_fd(int fd); 20 int btf_get_info_by_fd(const struct btf *btf, 21 const union bpf_attr *attr, 22 union bpf_attr __user *uattr); 23 /* Figure out the size of a type_id. If type_id is a modifier 24 * (e.g. const), it will be resolved to find out the type with size. 25 * 26 * For example: 27 * In describing "const void *", type_id is "const" and "const" 28 * refers to "void *". The return type will be "void *". 29 * 30 * If type_id is a simple "int", then return type will be "int". 31 * 32 * @btf: struct btf object 33 * @type_id: Find out the size of type_id. The type_id of the return 34 * type is set to *type_id. 35 * @ret_size: It can be NULL. If not NULL, the size of the return 36 * type is set to *ret_size. 37 * Return: The btf_type (resolved to another type with size info if needed). 38 * NULL is returned if type_id itself does not have size info 39 * (e.g. void) or it cannot be resolved to another type that 40 * has size info. 41 * *type_id and *ret_size will not be changed in the 42 * NULL return case. 43 */ 44 const struct btf_type *btf_type_id_size(const struct btf *btf, 45 u32 *type_id, 46 u32 *ret_size); 47 void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj, 48 struct seq_file *m); 49 int btf_get_fd_by_id(u32 id); 50 u32 btf_id(const struct btf *btf); 51 bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s, 52 const struct btf_member *m, 53 u32 expected_offset, u32 expected_size); 54 int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t); 55 bool btf_type_is_void(const struct btf_type *t); 56 57 static inline bool btf_type_is_ptr(const struct btf_type *t) 58 { 59 return BTF_INFO_KIND(t->info) == BTF_KIND_PTR; 60 } 61 62 static inline bool btf_type_is_int(const struct btf_type *t) 63 { 64 return BTF_INFO_KIND(t->info) == BTF_KIND_INT; 65 } 66 67 static inline bool btf_type_is_enum(const struct btf_type *t) 68 { 69 return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM; 70 } 71 72 static inline bool btf_type_is_typedef(const struct btf_type *t) 73 { 74 return BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF; 75 } 76 77 static inline bool btf_type_is_func(const struct btf_type *t) 78 { 79 return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC; 80 } 81 82 static inline bool btf_type_is_func_proto(const struct btf_type *t) 83 { 84 return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO; 85 } 86 87 #ifdef CONFIG_BPF_SYSCALL 88 const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id); 89 const char *btf_name_by_offset(const struct btf *btf, u32 offset); 90 struct btf *btf_parse_vmlinux(void); 91 struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog); 92 #else 93 static inline const struct btf_type *btf_type_by_id(const struct btf *btf, 94 u32 type_id) 95 { 96 return NULL; 97 } 98 static inline const char *btf_name_by_offset(const struct btf *btf, 99 u32 offset) 100 { 101 return NULL; 102 } 103 #endif 104 105 #endif 106