/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright 2012 Konstantin Belousov <kib@FreeBSD.ORG>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _SYS_VDSO_H
#define _SYS_VDSO_H

#include <sys/types.h>
#include <machine/vdso.h>

struct vdso_timehands {
        uint32_t        th_algo;
        uint32_t        th_gen;
        uint64_t        th_scale;
        uint32_t        th_offset_count;
        uint32_t        th_counter_mask;
        struct bintime  th_offset;
        struct bintime  th_boottime;
        VDSO_TIMEHANDS_MD
};

struct vdso_timekeep {
        uint32_t        tk_ver;
        uint32_t        tk_enabled;
        uint32_t        tk_current;
        struct vdso_timehands   tk_th[];
};

#define VDSO_TK_CURRENT_BUSY    0xffffffff
#define VDSO_TK_VER_1           0x1
#define VDSO_TK_VER_CURR        VDSO_TK_VER_1
#define VDSO_TH_ALGO_1          0x1
#define VDSO_TH_ALGO_2          0x2
#define VDSO_TH_ALGO_3          0x3
#define VDSO_TH_ALGO_4          0x4

struct vdso_fxrng_generation_1 {
        uint32_t        fx_vdso_version;        /* 1 */
        uint32_t        fx_generation32;
        uint64_t        _fx_reserved;
};
_Static_assert(sizeof(struct vdso_fxrng_generation_1) == 16, "");
#define vdso_fxrng_generation   vdso_fxrng_generation_1

/* fx_vdso_version values: */
#define VDSO_FXRNG_VER_1        0x1
#define VDSO_FXRNG_VER_CURR     VDSO_FXRNG_VER_1

#ifndef _KERNEL

struct timespec;
struct timeval;
struct timezone;

int __vdso_clock_gettime(clockid_t clock_id, struct timespec *ts);
int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz);
int __vdso_gettc(const struct vdso_timehands *vdso_th, u_int *tc);
int __vdso_gettimekeep(struct vdso_timekeep **tk);

#endif

#ifdef _KERNEL

struct timecounter;

struct vdso_sv_tk {
        int             sv_timekeep_off;
        int             sv_timekeep_curr;
        uint32_t        sv_timekeep_gen;
};

#ifdef RANDOM_FENESTRASX
void fxrng_push_seed_generation(uint64_t gen);
#endif
void timekeep_push_vdso(void);

uint32_t tc_fill_vdso_timehands(struct vdso_timehands *vdso_th);

/*
 * The cpu_fill_vdso_timehands() function should fill MD-part of the
 * struct vdso_timehands, which is both machine- and
 * timecounter-depended. The return value should be 1 if fast
 * userspace timecounter is enabled by hardware, and 0 otherwise. The
 * global sysctl enable override is handled by machine-independed code
 * after cpu_fill_vdso_timehands() call is made.
 */
uint32_t cpu_fill_vdso_timehands(struct vdso_timehands *vdso_th,
    struct timecounter *tc);

struct vdso_sv_tk *alloc_sv_tk(void);

#define VDSO_TH_NUM     4

#ifdef COMPAT_FREEBSD32

/*
 * i386 is the only arch with a 32 bit time_t.
 */
struct bintime32 {
#if defined(__amd64__)
        uint32_t        sec;
#else
        uint64_t        sec;
#endif
        uint32_t        frac[2];
};

struct vdso_timehands32 {
        uint32_t        th_algo;
        uint32_t        th_gen;
        uint32_t        th_scale[2];
        uint32_t        th_offset_count;
        uint32_t        th_counter_mask;
        struct bintime32        th_offset;
        struct bintime32        th_boottime;
        VDSO_TIMEHANDS_MD32
};

struct vdso_timekeep32 {
        uint32_t        tk_ver;
        uint32_t        tk_enabled;
        uint32_t        tk_current;
        struct vdso_timehands32 tk_th[];
};

uint32_t tc_fill_vdso_timehands32(struct vdso_timehands32 *vdso_th32);
uint32_t cpu_fill_vdso_timehands32(struct vdso_timehands32 *vdso_th32,
    struct timecounter *tc);
struct vdso_sv_tk *alloc_sv_tk_compat32(void);

#endif
#endif

#endif