| /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ |
| /* Copyright (c) 2018 Facebook */ |
| #ifndef _UAPI__LINUX_BTF_H__ |
| #define _UAPI__LINUX_BTF_H__ |
| |
| #include <linux/types.h> |
| |
| #define BTF_MAGIC 0xeB9F |
| #define BTF_VERSION 1 |
| |
| struct btf_header { |
| __u16 magic; |
| __u8 version; |
| __u8 flags; |
| __u32 hdr_len; |
| |
| /* All offsets are in bytes relative to the end of this header */ |
| __u32 type_off; /* offset of type section */ |
| __u32 type_len; /* length of type section */ |
| __u32 str_off; /* offset of string section */ |
| __u32 str_len; /* length of string section */ |
| }; |
| |
| /* Max # of type identifier */ |
| #define BTF_MAX_TYPE 0x000fffff |
| /* Max offset into the string section */ |
| #define BTF_MAX_NAME_OFFSET 0x00ffffff |
| /* Max # of struct/union/enum members or func args */ |
| #define BTF_MAX_VLEN 0xffff |
| |
| struct btf_type { |
| __u32 name_off; |
| /* "info" bits arrangement |
| * bits 0-15: vlen (e.g. # of struct's members) |
| * bits 16-23: unused |
| * bits 24-27: kind (e.g. int, ptr, array...etc) |
| * bits 28-30: unused |
| * bit 31: kind_flag, currently used by |
| * struct, union and fwd |
| */ |
| __u32 info; |
| /* "size" is used by INT, ENUM, STRUCT, UNION and DATASEC. |
| * "size" tells the size of the type it is describing. |
| * |
| * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT, |
| * FUNC, FUNC_PROTO and VAR. |
| * "type" is a type_id referring to another type. |
| */ |
| union { |
| __u32 size; |
| __u32 type; |
| }; |
| }; |
| |
| #define BTF_INFO_KIND(info) (((info) >> 24) & 0x1f) |
| #define BTF_INFO_VLEN(info) ((info) & 0xffff) |
| #define BTF_INFO_KFLAG(info) ((info) >> 31) |
| |
| #define BTF_KIND_UNKN 0 /* Unknown */ |
| #define BTF_KIND_INT 1 /* Integer */ |
| #define BTF_KIND_PTR 2 /* Pointer */ |
| #define BTF_KIND_ARRAY 3 /* Array */ |
| #define BTF_KIND_STRUCT 4 /* Struct */ |
| #define BTF_KIND_UNION 5 /* Union */ |
| #define BTF_KIND_ENUM 6 /* Enumeration */ |
| #define BTF_KIND_FWD 7 /* Forward */ |
| #define BTF_KIND_TYPEDEF 8 /* Typedef */ |
| #define BTF_KIND_VOLATILE 9 /* Volatile */ |
| #define BTF_KIND_CONST 10 /* Const */ |
| #define BTF_KIND_RESTRICT 11 /* Restrict */ |
| #define BTF_KIND_FUNC 12 /* Function */ |
| #define BTF_KIND_FUNC_PROTO 13 /* Function Proto */ |
| #define BTF_KIND_VAR 14 /* Variable */ |
| #define BTF_KIND_DATASEC 15 /* Section */ |
| #define BTF_KIND_FLOAT 16 /* Floating point */ |
| #define BTF_KIND_MAX BTF_KIND_FLOAT |
| #define NR_BTF_KINDS (BTF_KIND_MAX + 1) |
| |
| /* For some specific BTF_KIND, "struct btf_type" is immediately |
| * followed by extra data. |
| */ |
| |
| /* BTF_KIND_INT is followed by a u32 and the following |
| * is the 32 bits arrangement: |
| */ |
| #define BTF_INT_ENCODING(VAL) (((VAL) & 0x0f000000) >> 24) |
| #define BTF_INT_OFFSET(VAL) (((VAL) & 0x00ff0000) >> 16) |
| #define BTF_INT_BITS(VAL) ((VAL) & 0x000000ff) |
| |
| /* Attributes stored in the BTF_INT_ENCODING */ |
| #define BTF_INT_SIGNED (1 << 0) |
| #define BTF_INT_CHAR (1 << 1) |
| #define BTF_INT_BOOL (1 << 2) |
| |
| /* BTF_KIND_ENUM is followed by multiple "struct btf_enum". |
| * The exact number of btf_enum is stored in the vlen (of the |
| * info in "struct btf_type"). |
| */ |
| struct btf_enum { |
| __u32 name_off; |
| __s32 val; |
| }; |
| |
| /* BTF_KIND_ARRAY is followed by one "struct btf_array" */ |
| struct btf_array { |
| __u32 type; |
| __u32 index_type; |
| __u32 nelems; |
| }; |
| |
| /* BTF_KIND_STRUCT and BTF_KIND_UNION are followed |
| * by multiple "struct btf_member". The exact number |
| * of btf_member is stored in the vlen (of the info in |
| * "struct btf_type"). |
| */ |
| struct btf_member { |
| __u32 name_off; |
| __u32 type; |
| /* If the type info kind_flag is set, the btf_member offset |
| * contains both member bitfield size and bit offset. The |
| * bitfield size is set for bitfield members. If the type |
| * info kind_flag is not set, the offset contains only bit |
| * offset. |
| */ |
| __u32 offset; |
| }; |
| |
| /* If the struct/union type info kind_flag is set, the |
| * following two macros are used to access bitfield_size |
| * and bit_offset from btf_member.offset. |
| */ |
| #define BTF_MEMBER_BITFIELD_SIZE(val) ((val) >> 24) |
| #define BTF_MEMBER_BIT_OFFSET(val) ((val) & 0xffffff) |
| |
| /* BTF_KIND_FUNC_PROTO is followed by multiple "struct btf_param". |
| * The exact number of btf_param is stored in the vlen (of the |
| * info in "struct btf_type"). |
| */ |
| struct btf_param { |
| __u32 name_off; |
| __u32 type; |
| }; |
| |
| enum { |
| BTF_VAR_STATIC = 0, |
| BTF_VAR_GLOBAL_ALLOCATED = 1, |
| BTF_VAR_GLOBAL_EXTERN = 2, |
| }; |
| |
| enum btf_func_linkage { |
| BTF_FUNC_STATIC = 0, |
| BTF_FUNC_GLOBAL = 1, |
| BTF_FUNC_EXTERN = 2, |
| }; |
| |
| /* BTF_KIND_VAR is followed by a single "struct btf_var" to describe |
| * additional information related to the variable such as its linkage. |
| */ |
| struct btf_var { |
| __u32 linkage; |
| }; |
| |
| /* BTF_KIND_DATASEC is followed by multiple "struct btf_var_secinfo" |
| * to describe all BTF_KIND_VAR types it contains along with it's |
| * in-section offset as well as size. |
| */ |
| struct btf_var_secinfo { |
| __u32 type; |
| __u32 offset; |
| __u32 size; |
| }; |
| |
| #endif /* _UAPI__LINUX_BTF_H__ */ |