/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
/*
 *  IPv6 IOAM implementation
 *
 *  Author:
 *  Justin Iurman <justin.iurman@uliege.be>
 */

#ifndef _UAPI_LINUX_IOAM6_H
#define _UAPI_LINUX_IOAM6_H

#include <asm/byteorder.h>
#include <linux/types.h>

#define IOAM6_U16_UNAVAILABLE U16_MAX
#define IOAM6_U32_UNAVAILABLE U32_MAX
#define IOAM6_U64_UNAVAILABLE U64_MAX

#define IOAM6_DEFAULT_ID (IOAM6_U32_UNAVAILABLE >> 8)
#define IOAM6_DEFAULT_ID_WIDE (IOAM6_U64_UNAVAILABLE >> 8)
#define IOAM6_DEFAULT_IF_ID IOAM6_U16_UNAVAILABLE
#define IOAM6_DEFAULT_IF_ID_WIDE IOAM6_U32_UNAVAILABLE

/*
 * IPv6 IOAM Option Header
 */
struct ioam6_hdr {
        __u8 opt_type;
        __u8 opt_len;
        __u8 :8;                                /* reserved */
#define IOAM6_TYPE_PREALLOC 0
        __u8 type;
} __attribute__((packed));

/*
 * IOAM Trace Header
 */
struct ioam6_trace_hdr {
        __be16  namespace_id;

#if defined(__LITTLE_ENDIAN_BITFIELD)

        __u8    :1,                             /* unused */
                :1,                             /* unused */
                overflow:1,
                nodelen:5;

        __u8    remlen:7,
                :1;                             /* unused */

        union {
                __be32 type_be32;

                struct {
                        __u32   bit7:1,
                                bit6:1,
                                bit5:1,
                                bit4:1,
                                bit3:1,
                                bit2:1,
                                bit1:1,
                                bit0:1,
                                bit15:1,        /* unused */
                                bit14:1,        /* unused */
                                bit13:1,        /* unused */
                                bit12:1,        /* unused */
                                bit11:1,
                                bit10:1,
                                bit9:1,
                                bit8:1,
                                bit23:1,        /* reserved */
                                bit22:1,
                                bit21:1,        /* unused */
                                bit20:1,        /* unused */
                                bit19:1,        /* unused */
                                bit18:1,        /* unused */
                                bit17:1,        /* unused */
                                bit16:1,        /* unused */
                                :8;             /* reserved */
                } type;
        };

#elif defined(__BIG_ENDIAN_BITFIELD)

        __u8    nodelen:5,
                overflow:1,
                :1,                             /* unused */
                :1;                             /* unused */

        __u8    :1,                             /* unused */
                remlen:7;

        union {
                __be32 type_be32;

                struct {
                        __u32   bit0:1,
                                bit1:1,
                                bit2:1,
                                bit3:1,
                                bit4:1,
                                bit5:1,
                                bit6:1,
                                bit7:1,
                                bit8:1,
                                bit9:1,
                                bit10:1,
                                bit11:1,
                                bit12:1,        /* unused */
                                bit13:1,        /* unused */
                                bit14:1,        /* unused */
                                bit15:1,        /* unused */
                                bit16:1,        /* unused */
                                bit17:1,        /* unused */
                                bit18:1,        /* unused */
                                bit19:1,        /* unused */
                                bit20:1,        /* unused */
                                bit21:1,        /* unused */
                                bit22:1,
                                bit23:1,        /* reserved */
                                :8;             /* reserved */
                } type;
        };

#else
#error "Please fix <asm/byteorder.h>"
#endif

#define IOAM6_TRACE_DATA_SIZE_MAX 244
        __u8    data[];
} __attribute__((packed));

#endif /* _UAPI_LINUX_IOAM6_H */