114 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			114 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
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| /* Copyright (c) 2018 Facebook */
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| #ifndef _UAPI__LINUX_BTF_H__
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| #define _UAPI__LINUX_BTF_H__
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| 
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| #include <linux/types.h>
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| 
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| #define BTF_MAGIC	0xeB9F
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| #define BTF_VERSION	1
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| 
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| struct btf_header {
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| 	__u16	magic;
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| 	__u8	version;
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| 	__u8	flags;
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| 	__u32	hdr_len;
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| 
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| 	/* All offsets are in bytes relative to the end of this header */
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| 	__u32	type_off;	/* offset of type section	*/
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| 	__u32	type_len;	/* length of type section	*/
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| 	__u32	str_off;	/* offset of string section	*/
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| 	__u32	str_len;	/* length of string section	*/
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| };
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| 
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| /* Max # of type identifier */
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| #define BTF_MAX_TYPE	0x0000ffff
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| /* Max offset into the string section */
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| #define BTF_MAX_NAME_OFFSET	0x0000ffff
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| /* Max # of struct/union/enum members or func args */
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| #define BTF_MAX_VLEN	0xffff
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| 
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| struct btf_type {
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| 	__u32 name_off;
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| 	/* "info" bits arrangement
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| 	 * bits  0-15: vlen (e.g. # of struct's members)
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| 	 * bits 16-23: unused
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| 	 * bits 24-27: kind (e.g. int, ptr, array...etc)
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| 	 * bits 28-31: unused
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| 	 */
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| 	__u32 info;
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| 	/* "size" is used by INT, ENUM, STRUCT and UNION.
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| 	 * "size" tells the size of the type it is describing.
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| 	 *
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| 	 * "type" is used by PTR, TYPEDEF, VOLATILE, CONST and RESTRICT.
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| 	 * "type" is a type_id referring to another type.
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| 	 */
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| 	union {
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| 		__u32 size;
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| 		__u32 type;
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| 	};
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| };
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| 
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| #define BTF_INFO_KIND(info)	(((info) >> 24) & 0x0f)
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| #define BTF_INFO_VLEN(info)	((info) & 0xffff)
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| 
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| #define BTF_KIND_UNKN		0	/* Unknown	*/
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| #define BTF_KIND_INT		1	/* Integer	*/
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| #define BTF_KIND_PTR		2	/* Pointer	*/
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| #define BTF_KIND_ARRAY		3	/* Array	*/
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| #define BTF_KIND_STRUCT		4	/* Struct	*/
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| #define BTF_KIND_UNION		5	/* Union	*/
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| #define BTF_KIND_ENUM		6	/* Enumeration	*/
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| #define BTF_KIND_FWD		7	/* Forward	*/
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| #define BTF_KIND_TYPEDEF	8	/* Typedef	*/
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| #define BTF_KIND_VOLATILE	9	/* Volatile	*/
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| #define BTF_KIND_CONST		10	/* Const	*/
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| #define BTF_KIND_RESTRICT	11	/* Restrict	*/
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| #define BTF_KIND_MAX		11
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| #define NR_BTF_KINDS		12
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| 
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| /* For some specific BTF_KIND, "struct btf_type" is immediately
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|  * followed by extra data.
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|  */
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| 
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| /* BTF_KIND_INT is followed by a u32 and the following
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|  * is the 32 bits arrangement:
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|  */
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| #define BTF_INT_ENCODING(VAL)	(((VAL) & 0x0f000000) >> 24)
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| #define BTF_INT_OFFSET(VAL)	(((VAL  & 0x00ff0000)) >> 16)
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| #define BTF_INT_BITS(VAL)	((VAL)  & 0x000000ff)
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| 
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| /* Attributes stored in the BTF_INT_ENCODING */
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| #define BTF_INT_SIGNED	(1 << 0)
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| #define BTF_INT_CHAR	(1 << 1)
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| #define BTF_INT_BOOL	(1 << 2)
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| 
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| /* BTF_KIND_ENUM is followed by multiple "struct btf_enum".
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|  * The exact number of btf_enum is stored in the vlen (of the
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|  * info in "struct btf_type").
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|  */
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| struct btf_enum {
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| 	__u32	name_off;
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| 	__s32	val;
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| };
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| 
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| /* BTF_KIND_ARRAY is followed by one "struct btf_array" */
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| struct btf_array {
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| 	__u32	type;
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| 	__u32	index_type;
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| 	__u32	nelems;
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| };
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| 
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| /* BTF_KIND_STRUCT and BTF_KIND_UNION are followed
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|  * by multiple "struct btf_member".  The exact number
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|  * of btf_member is stored in the vlen (of the info in
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|  * "struct btf_type").
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|  */
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| struct btf_member {
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| 	__u32	name_off;
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| 	__u32	type;
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| 	__u32	offset;	/* offset in bits */
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| };
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| 
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| #endif /* _UAPI__LINUX_BTF_H__ */
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