/*-
 * SPDX-License-Identifier: BSD-4-Clause
 *
 * Copyright (c) 1996, 1997, 1998
 *      HD Associates, Inc.  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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by HD Associates, Inc
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES AND CONTRIBUTORS ``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 HD ASSOCIATES OR CONTRIBUTORS 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.
 */

/* p1003_1b: Real Time common code.
 */

#include <sys/cdefs.h>
#include "opt_posix.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/posix4.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/sysproto.h>

MALLOC_DEFINE(M_P31B, "p1003.1b", "Posix 1003.1B");

/* The system calls return ENOSYS if an entry is called that is not run-time
 * supported.  I am also logging since some programs start to use this when
 * they shouldn't.  That will be removed if annoying.
 */
int
syscall_not_present(struct thread *td, const char *s, struct nosys_args *uap)
{
        log(LOG_ERR, "cmd %s pid %d tried to use non-present %s\n",
                        td->td_name, td->td_proc->p_pid, s);

        /* a " return nosys(p, uap); " here causes a core dump.
         */

        return ENOSYS;
}

#if !defined(_KPOSIX_PRIORITY_SCHEDULING)

/* Not configured but loadable via a module:
 */

static int
sched_attach(void)
{
        return 0;
}

SYSCALL_NOT_PRESENT_GEN(sched_setparam)
SYSCALL_NOT_PRESENT_GEN(sched_getparam)
SYSCALL_NOT_PRESENT_GEN(sched_setscheduler)
SYSCALL_NOT_PRESENT_GEN(sched_getscheduler)
SYSCALL_NOT_PRESENT_GEN(sched_yield)
SYSCALL_NOT_PRESENT_GEN(sched_get_priority_max)
SYSCALL_NOT_PRESENT_GEN(sched_get_priority_min)
SYSCALL_NOT_PRESENT_GEN(sched_rr_get_interval)
#else

/* Configured in kernel version:
 */
static struct ksched *ksched;

static int
sched_attach(void)
{
        int ret = ksched_attach(&ksched);

        if (ret == 0)
                p31b_setcfg(CTL_P1003_1B_PRIORITY_SCHEDULING, 200112L);

        return ret;
}

int
sys_sched_setparam(struct thread *td, struct sched_setparam_args *uap)
{
        struct thread *targettd;
        struct proc *targetp;
        int e;
        struct sched_param sched_param;

        e = copyin(uap->param, &sched_param, sizeof(sched_param));
        if (e)
                return (e);

        if (uap->pid == 0) {
                targetp = td->td_proc;
                targettd = td;
                PROC_LOCK(targetp);
        } else {
                targetp = pfind(uap->pid);
                if (targetp == NULL)
                        return (ESRCH);
                targettd = FIRST_THREAD_IN_PROC(targetp);
        }

        e = kern_sched_setparam(td, targettd, &sched_param);
        PROC_UNLOCK(targetp);
        return (e);
}

int
kern_sched_setparam(struct thread *td, struct thread *targettd,
    struct sched_param *param)
{
        struct proc *targetp;
        int error;

        targetp = targettd->td_proc;
        PROC_LOCK_ASSERT(targetp, MA_OWNED);

        error = p_cansched(td, targetp);
        if (error == 0)
                error = ksched_setparam(ksched, targettd,
                    (const struct sched_param *)param);
        return (error);
}

int
sys_sched_getparam(struct thread *td, struct sched_getparam_args *uap)
{
        int e;
        struct sched_param sched_param;
        struct thread *targettd;
        struct proc *targetp;

        if (uap->pid == 0) {
                targetp = td->td_proc;
                targettd = td;
                PROC_LOCK(targetp);
        } else {
                targetp = pfind(uap->pid);
                if (targetp == NULL) {
                        return (ESRCH);
                }
                targettd = FIRST_THREAD_IN_PROC(targetp);
        }

        e = kern_sched_getparam(td, targettd, &sched_param);
        PROC_UNLOCK(targetp);
        if (e == 0)
                e = copyout(&sched_param, uap->param, sizeof(sched_param));
        return (e);
}

int
kern_sched_getparam(struct thread *td, struct thread *targettd,
    struct sched_param *param)
{
        struct proc *targetp;
        int error;

        targetp = targettd->td_proc;
        PROC_LOCK_ASSERT(targetp, MA_OWNED);

        error = p_cansee(td, targetp);
        if (error == 0)
                error = ksched_getparam(ksched, targettd, param);
        return (error);
}

int
sys_sched_setscheduler(struct thread *td, struct sched_setscheduler_args *uap)
{
        int e;
        struct sched_param sched_param;
        struct thread *targettd;
        struct proc *targetp;

        e = copyin(uap->param, &sched_param, sizeof(sched_param));
        if (e)
                return (e);

        if (uap->pid == 0) {
                targetp = td->td_proc;
                targettd = td;
                PROC_LOCK(targetp);
        } else {
                targetp = pfind(uap->pid);
                if (targetp == NULL)
                        return (ESRCH);
                targettd = FIRST_THREAD_IN_PROC(targetp);
        }

        e = kern_sched_setscheduler(td, targettd, uap->policy,
            &sched_param);
        PROC_UNLOCK(targetp);
        return (e);
}

int
kern_sched_setscheduler(struct thread *td, struct thread *targettd,
    int policy, struct sched_param *param)
{
        struct proc *targetp;
        int error;

        targetp = targettd->td_proc;
        PROC_LOCK_ASSERT(targetp, MA_OWNED);

        /* Only privileged users are allowed to set a scheduler policy. */
        error = priv_check(td, PRIV_SCHED_SETPOLICY);
        if (error)
                return (error);

        error = p_cansched(td, targetp);
        if (error == 0)
                error = ksched_setscheduler(ksched, targettd, policy,
                    (const struct sched_param *)param);
        return (error);
}

int
sys_sched_getscheduler(struct thread *td, struct sched_getscheduler_args *uap)
{
        int e, policy;
        struct thread *targettd;
        struct proc *targetp;

        if (uap->pid == 0) {
                targetp = td->td_proc;
                targettd = td;
                PROC_LOCK(targetp);
        } else {
                targetp = pfind(uap->pid);
                if (targetp == NULL)
                        return (ESRCH);
                targettd = FIRST_THREAD_IN_PROC(targetp);
        }

        e = kern_sched_getscheduler(td, targettd, &policy);
        PROC_UNLOCK(targetp);
        if (e == 0)
                td->td_retval[0] = policy;

        return (e);
}

int
kern_sched_getscheduler(struct thread *td, struct thread *targettd,
    int *policy)
{
        struct proc *targetp;
        int error;

        targetp = targettd->td_proc;
        PROC_LOCK_ASSERT(targetp, MA_OWNED);

        error = p_cansee(td, targetp);
        if (error == 0)
                error = ksched_getscheduler(ksched, targettd, policy);
        return (error);
}

int
sys_sched_yield(struct thread *td, struct sched_yield_args *uap)
{

        sched_relinquish(td);
        return (0);
}

int
sys_sched_get_priority_max(struct thread *td,
    struct sched_get_priority_max_args *uap)
{
        int error, prio;

        error = ksched_get_priority_max(ksched, uap->policy, &prio);
        td->td_retval[0] = prio;
        return (error);
}

int
sys_sched_get_priority_min(struct thread *td,
    struct sched_get_priority_min_args *uap)
{
        int error, prio;

        error = ksched_get_priority_min(ksched, uap->policy, &prio);
        td->td_retval[0] = prio;
        return (error);
}

int
sys_sched_rr_get_interval(struct thread *td,
    struct sched_rr_get_interval_args *uap)
{
        struct timespec timespec;
        int error;

        error = kern_sched_rr_get_interval(td, uap->pid, &timespec);
        if (error == 0)
                error = copyout(&timespec, uap->interval, sizeof(timespec));
        return (error);
}

int
kern_sched_rr_get_interval(struct thread *td, pid_t pid,
    struct timespec *ts)
{
        int e;
        struct thread *targettd;
        struct proc *targetp;

        if (pid == 0) {
                targettd = td;
                targetp = td->td_proc;
                PROC_LOCK(targetp);
        } else {
                targetp = pfind(pid);
                if (targetp == NULL)
                        return (ESRCH);
                targettd = FIRST_THREAD_IN_PROC(targetp);
        }

        e = kern_sched_rr_get_interval_td(td, targettd, ts);
        PROC_UNLOCK(targetp);
        return (e);
}

int
kern_sched_rr_get_interval_td(struct thread *td, struct thread *targettd,
    struct timespec *ts)
{
        struct proc *p;
        int error;

        p = targettd->td_proc;
        PROC_LOCK_ASSERT(p, MA_OWNED);

        error = p_cansee(td, p);
        if (error == 0)
                error = ksched_rr_get_interval(ksched, targettd, ts);
        return (error);
}
#endif

static void
p31binit(void *notused)
{
        (void) sched_attach();
        p31b_setcfg(CTL_P1003_1B_PAGESIZE, PAGE_SIZE);
}

SYSINIT(p31b, SI_SUB_P1003_1B, SI_ORDER_FIRST, p31binit, NULL);