/**************************************************************************
 *
 * Copyright 2008-2009 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/
/*
 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
 */

#include <sys/cdefs.h>
#include <dev/drm2/drmP.h>
#include <dev/drm2/drm_global.h>

MALLOC_DEFINE(M_DRM_GLOBAL, "drm_global", "DRM Global Items");

struct drm_global_item {
        struct sx mutex;
        void *object;
        int refcount;
};

static struct drm_global_item glob[DRM_GLOBAL_NUM];

void drm_global_init(void)
{
        int i;

        for (i = 0; i < DRM_GLOBAL_NUM; ++i) {
                struct drm_global_item *item = &glob[i];
                sx_init(&item->mutex, "drmgi");
                item->object = NULL;
                item->refcount = 0;
        }
}

void drm_global_release(void)
{
        int i;
        for (i = 0; i < DRM_GLOBAL_NUM; ++i) {
                struct drm_global_item *item = &glob[i];
                MPASS(item->object == NULL);
                MPASS(item->refcount == 0);
                sx_destroy(&item->mutex);
        }
}

int drm_global_item_ref(struct drm_global_reference *ref)
{
        int ret;
        struct drm_global_item *item = &glob[ref->global_type];

        sx_xlock(&item->mutex);
        if (item->refcount == 0) {
                item->object = malloc(ref->size, M_DRM_GLOBAL,
                    M_NOWAIT | M_ZERO);
                if (unlikely(item->object == NULL)) {
                        ret = -ENOMEM;
                        goto out_err;
                }

                ref->object = item->object;
                ret = ref->init(ref);
                if (unlikely(ret != 0))
                        goto out_err;

        }
        ++item->refcount;
        ref->object = item->object;
        sx_xunlock(&item->mutex);
        return 0;
out_err:
        sx_xunlock(&item->mutex);
        item->object = NULL;
        return ret;
}
EXPORT_SYMBOL(drm_global_item_ref);

void drm_global_item_unref(struct drm_global_reference *ref)
{
        struct drm_global_item *item = &glob[ref->global_type];

        sx_xlock(&item->mutex);
        MPASS(item->refcount != 0);
        MPASS(ref->object == item->object);
        if (--item->refcount == 0) {
                ref->release(ref);
                free(item->object, M_DRM_GLOBAL);
                item->object = NULL;
        }
        sx_xunlock(&item->mutex);
}
EXPORT_SYMBOL(drm_global_item_unref);