/*
 * Copyright (c) 2013-2014 Richard Braun.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <errno.h>
#include <stddef.h>

#include <kern/bitmap.h>
#include <kern/cpumap.h>
#include <kern/init.h>
#include <kern/kmem.h>
#include <kern/macros.h>
#include <machine/cpu.h>

static struct cpumap cpumap_active_cpus __read_mostly = { { 1 } };

static struct kmem_cache cpumap_cache;

static int __init
cpumap_setup(void)
{
    unsigned int i, nr_cpus;

    kmem_cache_init(&cpumap_cache, "cpumap", sizeof(struct cpumap), 0, NULL, 0);
    cpumap_zero(&cpumap_active_cpus);
    nr_cpus = cpu_count();

    for (i = 0; i < nr_cpus; i++) {
        cpumap_set(&cpumap_active_cpus, i);
    }

    return 0;
}

INIT_OP_DEFINE(cpumap_setup,
               INIT_OP_DEP(kmem_setup, true),
               INIT_OP_DEP(cpu_mp_probe, true));

const struct cpumap *
cpumap_all(void)
{
    return &cpumap_active_cpus;
}

int
cpumap_create(struct cpumap **cpumapp)
{
    struct cpumap *cpumap;

    cpumap = kmem_cache_alloc(&cpumap_cache);

    if (cpumap == NULL) {
        return ENOMEM;
    }

    *cpumapp = cpumap;
    return 0;
}

void
cpumap_destroy(struct cpumap *cpumap)
{
    kmem_cache_free(&cpumap_cache, cpumap);
}

int
cpumap_check(const struct cpumap *cpumap)
{
    int index;

    index = bitmap_find_first(cpumap->cpus, cpu_count());

    if (index == -1) {
        return EINVAL;
    }

    return 0;
}