/* 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 24-28: kind (e.g. int, ptr, array...etc)	 * bits 29-30: unused	 * bit     31: kind_flag, currently used by	 *             struct, union, enum, fwd, enum64,	 *             decl_tag and type_tag	 */	__u32 info;	/* "size" is used by INT, ENUM, STRUCT, UNION, DATASEC and ENUM64.	 * "size" tells the size of the type it is describing.	 *	 * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,	 * FUNC, FUNC_PROTO, VAR, DECL_TAG and TYPE_TAG.	 * "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) enum {	BTF_KIND_UNKN		= 0,	/* Unknown	*/	BTF_KIND_INT		= 1,	/* Integer	*/	BTF_KIND_PTR		= 2,	/* Pointer	*/	BTF_KIND_ARRAY		= 3,	/* Array	*/	BTF_KIND_STRUCT		= 4,	/* Struct	*/	BTF_KIND_UNION		= 5,	/* Union	*/	BTF_KIND_ENUM		= 6,	/* Enumeration up to 32-bit values */	BTF_KIND_FWD		= 7,	/* Forward	*/	BTF_KIND_TYPEDEF	= 8,	/* Typedef	*/	BTF_KIND_VOLATILE	= 9,	/* Volatile	*/	BTF_KIND_CONST		= 10,	/* Const	*/	BTF_KIND_RESTRICT	= 11,	/* Restrict	*/	BTF_KIND_FUNC		= 12,	/* Function	*/	BTF_KIND_FUNC_PROTO	= 13,	/* Function Proto	*/	BTF_KIND_VAR		= 14,	/* Variable	*/	BTF_KIND_DATASEC	= 15,	/* Section	*/	BTF_KIND_FLOAT		= 16,	/* Floating point	*/	BTF_KIND_DECL_TAG	= 17,	/* Decl Tag */	BTF_KIND_TYPE_TAG	= 18,	/* Type Tag */	BTF_KIND_ENUM64		= 19,	/* Enumeration up to 64-bit values */ 	NR_BTF_KINDS,	BTF_KIND_MAX		= NR_BTF_KINDS - 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;}; /* BTF_KIND_DECL_TAG is followed by a single "struct btf_decl_tag" to describe * additional information related to the tag applied location. * If component_idx == -1, the tag is applied to a struct, union, * variable or function. Otherwise, it is applied to a struct/union * member or a func argument, and component_idx indicates which member * or argument (0 ... vlen-1). */struct btf_decl_tag {       __s32   component_idx;}; /* BTF_KIND_ENUM64 is followed by multiple "struct btf_enum64". * The exact number of btf_enum64 is stored in the vlen (of the * info in "struct btf_type"). */struct btf_enum64 {	__u32	name_off;	__u32	val_lo32;	__u32	val_hi32;}; #endif /* _UAPI__LINUX_BTF_H__ */