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The C and C++ Include Header Files

cat -n /usr/include/iproute2/bpf_elf.h

     1	/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
     2	#ifndef __BPF_ELF__
     3	#define __BPF_ELF__
     4	
     5	#include <asm/types.h>
     6	
     7	/* Note:
     8	 *
     9	 * Below ELF section names and bpf_elf_map structure definition
    10	 * are not (!) kernel ABI. It's rather a "contract" between the
    11	 * application and the BPF loader in tc. For compatibility, the
    12	 * section names should stay as-is. Introduction of aliases, if
    13	 * needed, are a possibility, though.
    14	 */
    15	
    16	/* ELF section names, etc */
    17	#define ELF_SECTION_LICENSE	"license"
    18	#define ELF_SECTION_MAPS	"maps"
    19	#define ELF_SECTION_PROG	"prog"
    20	#define ELF_SECTION_CLASSIFIER	"classifier"
    21	#define ELF_SECTION_ACTION	"action"
    22	
    23	#define ELF_MAX_MAPS		64
    24	#define ELF_MAX_LICENSE_LEN	128
    25	
    26	/* Object pinning settings */
    27	#define PIN_NONE		0
    28	#define PIN_OBJECT_NS		1
    29	#define PIN_GLOBAL_NS		2
    30	
    31	/* ELF map definition */
    32	struct bpf_elf_map {
    33		__u32 type;
    34		__u32 size_key;
    35		__u32 size_value;
    36		__u32 max_elem;
    37		__u32 flags;
    38		__u32 id;
    39		__u32 pinning;
    40		__u32 inner_id;
    41		__u32 inner_idx;
    42	};
    43	
    44	#define BPF_ANNOTATE_KV_PAIR(name, type_key, type_val)		\
    45		struct ____btf_map_##name {				\
    46			type_key key;					\
    47			type_val value;					\
    48		};							\
    49		struct ____btf_map_##name				\
    50		    __attribute__ ((section(".maps." #name), used))	\
    51		    ____btf_map_##name = { }
    52	
    53	#endif /* __BPF_ELF__ */