[linux-2.6-block.git] / drivers / gpu / drm / drm_global.c

/**************************************************************************
 *
 * 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 <linux/mutex.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <drm/drm_global.h>

struct drm_global_item {
	struct mutex 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];
		mutex_init(&item->mutex);
		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];
		BUG_ON(item->object != NULL);
		BUG_ON(item->refcount != 0);
	}
}

int drm_global_item_ref(struct drm_global_reference *ref)
{
	int ret = 0;
	struct drm_global_item *item = &glob[ref->global_type];

	mutex_lock(&item->mutex);
	if (item->refcount == 0) {
		ref->object = kzalloc(ref->size, GFP_KERNEL);
		if (unlikely(ref->object == NULL)) {
			ret = -ENOMEM;
			goto error_unlock;
		}
		ret = ref->init(ref);
		if (unlikely(ret != 0))
			goto error_free;

		item->object = ref->object;
	} else {
		ref->object = item->object;
	}

	++item->refcount;
	mutex_unlock(&item->mutex);
	return 0;

error_free:
	kfree(ref->object);
	ref->object = NULL;
error_unlock:
	mutex_unlock(&item->mutex);
	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];

	mutex_lock(&item->mutex);
	BUG_ON(item->refcount == 0);
	BUG_ON(ref->object != item->object);
	if (--item->refcount == 0) {
		ref->release(ref);
		item->object = NULL;
	}
	mutex_unlock(&item->mutex);
}
EXPORT_SYMBOL(drm_global_item_unref);
Commit	Line	Data
ba4e7d97 TH	1	/**************************************************************************
	2	*
	3	* Copyright 2008-2009 VMware, Inc., Palo Alto, CA., USA
	4	* All Rights Reserved.
	5	*
	6	* Permission is hereby granted, free of charge, to any person obtaining a
	7	* copy of this software and associated documentation files (the
	8	* "Software"), to deal in the Software without restriction, including
	9	* without limitation the rights to use, copy, modify, merge, publish,
	10	* distribute, sub license, and/or sell copies of the Software, and to
	11	* permit persons to whom the Software is furnished to do so, subject to
	12	* the following conditions:
	13	*
	14	* The above copyright notice and this permission notice (including the
	15	* next paragraph) shall be included in all copies or substantial portions
	16	* of the Software.
	17	*
	18	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	19	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	20	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	21	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	22	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	23	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	24	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	25	*
	26	**************************************************************************/
	27	/*
	28	* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
	29	*/
	30
ba4e7d97 TH	31	#include <linux/mutex.h>
	32	#include <linux/slab.h>
	33	#include <linux/module.h>
760285e7	34	#include <drm/drm_global.h>
ba4e7d97	35
ba4420c2	36	struct drm_global_item {
ba4e7d97 TH	37	struct mutex mutex;
	38	void *object;
	39	int refcount;
	40	};
	41
ba4420c2	42	static struct drm_global_item glob[DRM_GLOBAL_NUM];
ba4e7d97	43
ba4420c2	44	void drm_global_init(void)
ba4e7d97 TH	45	{
	46	int i;
	47
ba4420c2 DA	48	for (i = 0; i < DRM_GLOBAL_NUM; ++i) {
ba4420c2 DA	49	struct drm_global_item *item = &glob[i];
ba4e7d97 TH	50	mutex_init(&item->mutex);
	51	item->object = NULL;
	52	item->refcount = 0;
	53	}
	54	}
	55
ba4420c2	56	void drm_global_release(void)
ba4e7d97 TH	57	{
ba4e7d97 TH	58	int i;
ba4420c2 DA	59	for (i = 0; i < DRM_GLOBAL_NUM; ++i) {
ba4420c2 DA	60	struct drm_global_item *item = &glob[i];
ba4e7d97 TH	61	BUG_ON(item->object != NULL);
	62	BUG_ON(item->refcount != 0);
	63	}
	64	}
	65
ba4420c2	66	int drm_global_item_ref(struct drm_global_reference *ref)
ba4e7d97	67	{
d28d6e6f	68	int ret = 0;
ba4420c2	69	struct drm_global_item *item = &glob[ref->global_type];
ba4e7d97 TH	70
	71	mutex_lock(&item->mutex);
	72	if (item->refcount == 0) {
d28d6e6f HR	73	ref->object = kzalloc(ref->size, GFP_KERNEL);
d28d6e6f HR	74	if (unlikely(ref->object == NULL)) {
ba4e7d97	75	ret = -ENOMEM;
d28d6e6f	76	goto error_unlock;
ba4e7d97	77	}
ba4e7d97 TH	78	ret = ref->init(ref);
ba4e7d97 TH	79	if (unlikely(ret != 0))
d28d6e6f	80	goto error_free;
ba4e7d97	81
d28d6e6f HR	82	item->object = ref->object;
	83	} else {
	84	ref->object = item->object;
ba4e7d97	85	}
d28d6e6f	86
df748b02	87	++item->refcount;
ba4e7d97 TH	88	mutex_unlock(&item->mutex);
ba4e7d97 TH	89	return 0;
d28d6e6f HR	90
	91	error_free:
	92	kfree(ref->object);
	93	ref->object = NULL;
	94	error_unlock:
ba4e7d97	95	mutex_unlock(&item->mutex);
ba4e7d97 TH	96	return ret;
ba4e7d97 TH	97	}
ba4420c2	98	EXPORT_SYMBOL(drm_global_item_ref);
ba4e7d97	99
ba4420c2	100	void drm_global_item_unref(struct drm_global_reference *ref)
ba4e7d97	101	{
ba4420c2	102	struct drm_global_item *item = &glob[ref->global_type];
ba4e7d97 TH	103
	104	mutex_lock(&item->mutex);
	105	BUG_ON(item->refcount == 0);
	106	BUG_ON(ref->object != item->object);
	107	if (--item->refcount == 0) {
	108	ref->release(ref);
ba4e7d97 TH	109	item->object = NULL;
	110	}
	111	mutex_unlock(&item->mutex);
	112	}
ba4420c2	113	EXPORT_SYMBOL(drm_global_item_unref);
ba4e7d97	114