/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/var.h>
#include <sys/thread.h>
#include <sys/cpuvar.h>
#include <sys/kstat.h>
#include <sys/uadmin.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/cmn_err.h>
#include <sys/procset.h>
#include <sys/processor.h>
#include <sys/debug.h>
#include <sys/task.h>
#include <sys/project.h>
#include <sys/zone.h>
#include <sys/contract_impl.h>
#include <sys/contract/process_impl.h>

/*
 * Bind all the threads of a process to a CPU.
 */
static int
cpu_bind_process(proc_t *pp, processorid_t bind, processorid_t *obind,
    int *error)
{
        kthread_t       *tp;
        kthread_t       *fp;
        int             err = 0;
        int             i;

        ASSERT(MUTEX_HELD(&pidlock));

        /* skip kernel processes */
        if (pp->p_flag & SSYS) {
                *obind = PBIND_NONE;
                *error = ENOTSUP;
                return (0);
        }

        mutex_enter(&pp->p_lock);
        tp = pp->p_tlist;
        if (tp != NULL) {
                fp = tp;
                do {
                        i = cpu_bind_thread(tp, bind, obind, error);
                        if (err == 0)
                                err = i;
                } while ((tp = tp->t_forw) != fp);
        }

        mutex_exit(&pp->p_lock);
        return (err);
}

/*
 * Bind all the processes of a task to a CPU.
 */
static int
cpu_bind_task(task_t *tk, processorid_t bind, processorid_t *obind,
    int *error)
{
        proc_t  *p;
        int     err = 0;
        int     i;

        ASSERT(MUTEX_HELD(&pidlock));

        if ((p = tk->tk_memb_list) == NULL)
                return (ESRCH);

        do {
                if (!(p->p_flag & SSYS)) {
                        i = cpu_bind_process(p, bind, obind, error);
                        if (err == 0)
                                err = i;
                }
        } while ((p = p->p_tasknext) != tk->tk_memb_list);

        return (err);
}

/*
 * Bind all the processes in a project to a CPU.
 */
static int
cpu_bind_project(kproject_t *kpj, processorid_t bind, processorid_t *obind,
    int *error)
{
        proc_t *p;
        int err = 0;
        int i;

        ASSERT(MUTEX_HELD(&pidlock));

        for (p = practive; p != NULL; p = p->p_next) {
                if (p->p_tlist == NULL)
                        continue;
                if (p->p_task->tk_proj == kpj && !(p->p_flag & SSYS)) {
                        i = cpu_bind_process(p, bind, obind, error);
                        if (err == 0)
                                err = i;
                }
        }
        return (err);
}

/*
 * Bind all the processes in a zone to a CPU.
 */
int
cpu_bind_zone(zone_t *zptr, processorid_t bind, processorid_t *obind,
    int *error)
{
        proc_t *p;
        int err = 0;
        int i;

        ASSERT(MUTEX_HELD(&pidlock));

        for (p = practive; p != NULL; p = p->p_next) {
                if (p->p_tlist == NULL)
                        continue;
                if (p->p_zone == zptr && !(p->p_flag & SSYS)) {
                        i = cpu_bind_process(p, bind, obind, error);
                        if (err == 0)
                                err = i;
                }
        }
        return (err);
}

/*
 * Bind all the processes in a process contract to a CPU.
 */
int
cpu_bind_contract(cont_process_t *ctp, processorid_t bind, processorid_t *obind,
    int *error)
{
        proc_t *p;
        int err = 0;
        int i;

        ASSERT(MUTEX_HELD(&pidlock));

        for (p = practive; p != NULL; p = p->p_next) {
                if (p->p_tlist == NULL)
                        continue;
                if (p->p_ct_process == ctp) {
                        i = cpu_bind_process(p, bind, obind, error);
                        if (err == 0)
                                err = i;
                }
        }
        return (err);
}

/*
 * processor_bind(2) - Processor binding interfaces.
 */
int
processor_bind(idtype_t idtype, id_t id, processorid_t bind,
    processorid_t *obindp)
{
        processorid_t   obind = PBIND_NONE;
        int             ret = 0;
        int             err = 0;
        cpu_t           *cp;
        kthread_id_t    tp;
        proc_t          *pp;
        task_t          *tk;
        kproject_t      *kpj;
        zone_t          *zptr;
        contract_t      *ct;

        /*
         * Since we might be making a binding to a processor, hold the
         * cpu_lock so that the processor cannot be taken offline while
         * we do this.
         */
        mutex_enter(&cpu_lock);

        /*
         * Check to be sure binding processor ID is valid.
         */
        switch (bind) {
        default:
                if ((cp = cpu_get(bind)) == NULL ||
                    (cp->cpu_flags & (CPU_QUIESCED | CPU_OFFLINE)))
                        ret = EINVAL;
                else if ((cp->cpu_flags & CPU_READY) == 0)
                        ret = EIO;
                break;

        case PBIND_NONE:
        case PBIND_QUERY:
        case PBIND_HARD:
        case PBIND_SOFT:
        case PBIND_QUERY_TYPE:
                break;
        }

        if (ret) {
                mutex_exit(&cpu_lock);
                return (set_errno(ret));
        }

        switch (idtype) {
        case P_LWPID:
                pp = curproc;
                mutex_enter(&pp->p_lock);
                if (id == P_MYID) {
                        ret = cpu_bind_thread(curthread, bind, &obind, &err);
                } else {
                        int     found = 0;

                        tp = pp->p_tlist;
                        do {
                                if (tp->t_tid == id) {
                                        ret = cpu_bind_thread(tp,
                                            bind, &obind, &err);
                                        found = 1;
                                        break;
                                }
                        } while ((tp = tp->t_forw) != pp->p_tlist);
                        if (!found)
                                ret = ESRCH;
                }
                mutex_exit(&pp->p_lock);
                break;

        case P_PID:
                /*
                 * Note.  Cannot use dotoprocs here because it doesn't find
                 * system class processes, which are legal to query.
                 */
                mutex_enter(&pidlock);
                if (id == P_MYID) {
                        ret = cpu_bind_process(curproc, bind, &obind, &err);
                } else if ((pp = prfind(id)) != NULL) {
                        ret = cpu_bind_process(pp, bind, &obind, &err);
                } else {
                        ret = ESRCH;
                }
                mutex_exit(&pidlock);
                break;

        case P_TASKID:
                mutex_enter(&pidlock);
                if (id == P_MYID) {
                        proc_t *p = curproc;
                        id = p->p_task->tk_tkid;
                }

                if ((tk = task_hold_by_id(id)) != NULL) {
                        ret = cpu_bind_task(tk, bind, &obind, &err);
                        mutex_exit(&pidlock);
                        task_rele(tk);
                } else {
                        mutex_exit(&pidlock);
                        ret = ESRCH;
                }
                break;

        case P_PROJID:
                pp = curproc;
                if (id == P_MYID)
                        id = curprojid();
                if ((kpj = project_hold_by_id(id, pp->p_zone,
                    PROJECT_HOLD_FIND)) == NULL) {
                        ret = ESRCH;
                } else {
                        mutex_enter(&pidlock);
                        ret = cpu_bind_project(kpj, bind, &obind, &err);
                        mutex_exit(&pidlock);
                        project_rele(kpj);
                }
                break;

        case P_ZONEID:
                if (id == P_MYID)
                        id = getzoneid();

                if ((zptr = zone_find_by_id(id)) == NULL) {
                        ret = ESRCH;
                } else {
                        mutex_enter(&pidlock);
                        ret = cpu_bind_zone(zptr, bind, &obind, &err);
                        mutex_exit(&pidlock);
                        zone_rele(zptr);
                }
                break;

        case P_CTID:
                if (id == P_MYID)
                        id = PRCTID(curproc);

                if ((ct = contract_type_ptr(process_type, id,
                    curproc->p_zone->zone_uniqid)) == NULL) {
                        ret = ESRCH;
                } else {
                        mutex_enter(&pidlock);
                        ret = cpu_bind_contract(ct->ct_data,
                            bind, &obind, &err);
                        mutex_exit(&pidlock);
                        contract_rele(ct);
                }
                break;

        case P_CPUID:
                if (id == P_MYID || bind != PBIND_NONE || cpu_get(id) == NULL)
                        ret = EINVAL;
                else
                        ret = cpu_unbind(id, B_TRUE);
                break;

        case P_ALL:
                if (id == P_MYID || bind != PBIND_NONE) {
                        ret = EINVAL;
                } else {
                        int i;
                        cpu_t *cp = cpu_list;
                        do {
                                if ((cp->cpu_flags & CPU_EXISTS) == 0)
                                        continue;
                                i = cpu_unbind(cp->cpu_id, B_TRUE);
                                if (ret == 0)
                                        ret = i;
                        } while ((cp = cp->cpu_next) != cpu_list);
                }
                break;

        default:
                /*
                 * Spec says this is invalid, even though we could
                 * handle other idtypes.
                 */
                ret = EINVAL;
                break;
        }
        mutex_exit(&cpu_lock);

        /*
         * If no search error occurred, see if any permissions errors did.
         */
        if (ret == 0)
                ret = err;

        if (ret == 0 && obindp != NULL)
                if (copyout((caddr_t)&obind, (caddr_t)obindp,
                    sizeof (obind)) == -1)
                        ret = EFAULT;
        return (ret ? set_errno(ret) : 0);      /* return success or failure */
}