[linux-2.6-block.git] / include / linux / reservation.h

/*
 * Header file for reservations for dma-buf and ttm
 *
 * Copyright(C) 2011 Linaro Limited. All rights reserved.
 * Copyright (C) 2012-2013 Canonical Ltd
 * Copyright (C) 2012 Texas Instruments
 *
 * Authors:
 * Rob Clark <robdclark@gmail.com>
 * Maarten Lankhorst <maarten.lankhorst@canonical.com>
 * Thomas Hellstrom <thellstrom-at-vmware-dot-com>
 *
 * Based on bo.c which bears the following copyright notice,
 * but is dual licensed:
 *
 * Copyright (c) 2006-2009 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.
 */
#ifndef _LINUX_RESERVATION_H
#define _LINUX_RESERVATION_H

#include <linux/ww_mutex.h>
#include <linux/fence.h>
#include <linux/slab.h>
#include <linux/seqlock.h>
#include <linux/rcupdate.h>

extern struct ww_class reservation_ww_class;
extern struct lock_class_key reservation_seqcount_class;
extern const char reservation_seqcount_string[];

struct reservation_object_list {
	struct rcu_head rcu;
	u32 shared_count, shared_max;
	struct fence __rcu *shared[];
};

struct reservation_object {
	struct ww_mutex lock;
	seqcount_t seq;

	struct fence __rcu *fence_excl;
	struct reservation_object_list __rcu *fence;
	struct reservation_object_list *staged;
};

#define reservation_object_held(obj) lockdep_is_held(&(obj)->lock.base)
#define reservation_object_assert_held(obj) \
	lockdep_assert_held(&(obj)->lock.base)

static inline void
reservation_object_init(struct reservation_object *obj)
{
	ww_mutex_init(&obj->lock, &reservation_ww_class);

	__seqcount_init(&obj->seq, reservation_seqcount_string, &reservation_seqcount_class);
	RCU_INIT_POINTER(obj->fence, NULL);
	RCU_INIT_POINTER(obj->fence_excl, NULL);
	obj->staged = NULL;
}

static inline void
reservation_object_fini(struct reservation_object *obj)
{
	int i;
	struct reservation_object_list *fobj;
	struct fence *excl;

	/*
	 * This object should be dead and all references must have
	 * been released to it, so no need to be protected with rcu.
	 */
	excl = rcu_dereference_protected(obj->fence_excl, 1);
	if (excl)
		fence_put(excl);

	fobj = rcu_dereference_protected(obj->fence, 1);
	if (fobj) {
		for (i = 0; i < fobj->shared_count; ++i)
			fence_put(rcu_dereference_protected(fobj->shared[i], 1));

		kfree(fobj);
	}
	kfree(obj->staged);

	ww_mutex_destroy(&obj->lock);
}

static inline struct reservation_object_list *
reservation_object_get_list(struct reservation_object *obj)
{
	return rcu_dereference_protected(obj->fence,
					 reservation_object_held(obj));
}

static inline struct fence *
reservation_object_get_excl(struct reservation_object *obj)
{
	return rcu_dereference_protected(obj->fence_excl,
					 reservation_object_held(obj));
}

int reservation_object_reserve_shared(struct reservation_object *obj);
void reservation_object_add_shared_fence(struct reservation_object *obj,
					 struct fence *fence);

void reservation_object_add_excl_fence(struct reservation_object *obj,
				       struct fence *fence);

int reservation_object_get_fences_rcu(struct reservation_object *obj,
				      struct fence **pfence_excl,
				      unsigned *pshared_count,
				      struct fence ***pshared);

long reservation_object_wait_timeout_rcu(struct reservation_object *obj,
					 bool wait_all, bool intr,
					 unsigned long timeout);

bool reservation_object_test_signaled_rcu(struct reservation_object *obj,
					  bool test_all);

#endif /* _LINUX_RESERVATION_H */
Commit	Line	Data
786d7257 ML	1	/*
	2	* Header file for reservations for dma-buf and ttm
	3	*
	4	* Copyright(C) 2011 Linaro Limited. All rights reserved.
	5	* Copyright (C) 2012-2013 Canonical Ltd
	6	* Copyright (C) 2012 Texas Instruments
	7	*
	8	* Authors:
0ba6b8fb	9	* Rob Clark <robdclark@gmail.com>
786d7257 ML	10	* Maarten Lankhorst <maarten.lankhorst@canonical.com>
	11	* Thomas Hellstrom <thellstrom-at-vmware-dot-com>
	12	*
	13	* Based on bo.c which bears the following copyright notice,
	14	* but is dual licensed:
	15	*
	16	* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
	17	* All Rights Reserved.
	18	*
	19	* Permission is hereby granted, free of charge, to any person obtaining a
	20	* copy of this software and associated documentation files (the
	21	* "Software"), to deal in the Software without restriction, including
	22	* without limitation the rights to use, copy, modify, merge, publish,
	23	* distribute, sub license, and/or sell copies of the Software, and to
	24	* permit persons to whom the Software is furnished to do so, subject to
	25	* the following conditions:
	26	*
	27	* The above copyright notice and this permission notice (including the
	28	* next paragraph) shall be included in all copies or substantial portions
	29	* of the Software.
	30	*
	31	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	32	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	33	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	34	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	35	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	36	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	37	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	38	*/
	39	#ifndef _LINUX_RESERVATION_H
	40	#define _LINUX_RESERVATION_H
	41
1b375dc3	42	#include <linux/ww_mutex.h>
0ba6b8fb ML	43	#include <linux/fence.h>
0ba6b8fb ML	44	#include <linux/slab.h>
3c3b177a ML	45	#include <linux/seqlock.h>
3c3b177a ML	46	#include <linux/rcupdate.h>
786d7257 ML	47
786d7257 ML	48	extern struct ww_class reservation_ww_class;
3c3b177a ML	49	extern struct lock_class_key reservation_seqcount_class;
3c3b177a ML	50	extern const char reservation_seqcount_string[];
786d7257	51
04a5faa8	52	struct reservation_object_list {
3c3b177a	53	struct rcu_head rcu;
04a5faa8	54	u32 shared_count, shared_max;
3c3b177a	55	struct fence __rcu *shared[];
04a5faa8 ML	56	};
04a5faa8 ML	57
786d7257 ML	58	struct reservation_object {
786d7257 ML	59	struct ww_mutex lock;
3c3b177a	60	seqcount_t seq;
0ba6b8fb	61
3c3b177a ML	62	struct fence __rcu *fence_excl;
3c3b177a ML	63	struct reservation_object_list __rcu *fence;
04a5faa8	64	struct reservation_object_list *staged;
786d7257 ML	65	};
786d7257 ML	66
3c3b177a	67	#define reservation_object_held(obj) lockdep_is_held(&(obj)->lock.base)
04a5faa8 ML	68	#define reservation_object_assert_held(obj) \
	69	lockdep_assert_held(&(obj)->lock.base)
	70
786d7257 ML	71	static inline void
	72	reservation_object_init(struct reservation_object *obj)
	73	{
	74	ww_mutex_init(&obj->lock, &reservation_ww_class);
0ba6b8fb	75
3c3b177a ML	76	__seqcount_init(&obj->seq, reservation_seqcount_string, &reservation_seqcount_class);
	77	RCU_INIT_POINTER(obj->fence, NULL);
	78	RCU_INIT_POINTER(obj->fence_excl, NULL);
04a5faa8	79	obj->staged = NULL;
786d7257 ML	80	}
	81
	82	static inline void
	83	reservation_object_fini(struct reservation_object *obj)
	84	{
0ba6b8fb	85	int i;
04a5faa8	86	struct reservation_object_list *fobj;
3c3b177a	87	struct fence *excl;
0ba6b8fb	88
04a5faa8 ML	89	/*
04a5faa8 ML	90	* This object should be dead and all references must have
3c3b177a	91	* been released to it, so no need to be protected with rcu.
04a5faa8	92	*/
3c3b177a ML	93	excl = rcu_dereference_protected(obj->fence_excl, 1);
	94	if (excl)
	95	fence_put(excl);
04a5faa8	96
3c3b177a	97	fobj = rcu_dereference_protected(obj->fence, 1);
04a5faa8 ML	98	if (fobj) {
04a5faa8 ML	99	for (i = 0; i < fobj->shared_count; ++i)
3c3b177a	100	fence_put(rcu_dereference_protected(fobj->shared[i], 1));
04a5faa8 ML	101
	102	kfree(fobj);
	103	}
	104	kfree(obj->staged);
0ba6b8fb	105
786d7257 ML	106	ww_mutex_destroy(&obj->lock);
	107	}
	108
04a5faa8 ML	109	static inline struct reservation_object_list *
	110	reservation_object_get_list(struct reservation_object *obj)
	111	{
3c3b177a ML	112	return rcu_dereference_protected(obj->fence,
3c3b177a ML	113	reservation_object_held(obj));
04a5faa8 ML	114	}
	115
	116	static inline struct fence *
	117	reservation_object_get_excl(struct reservation_object *obj)
	118	{
3c3b177a ML	119	return rcu_dereference_protected(obj->fence_excl,
3c3b177a ML	120	reservation_object_held(obj));
04a5faa8 ML	121	}
	122
	123	int reservation_object_reserve_shared(struct reservation_object *obj);
	124	void reservation_object_add_shared_fence(struct reservation_object *obj,
	125	struct fence *fence);
	126
	127	void reservation_object_add_excl_fence(struct reservation_object *obj,
	128	struct fence *fence);
	129
3c3b177a ML	130	int reservation_object_get_fences_rcu(struct reservation_object *obj,
	131	struct fence **pfence_excl,
	132	unsigned *pshared_count,
	133	struct fence ***pshared);
	134
	135	long reservation_object_wait_timeout_rcu(struct reservation_object *obj,
	136	bool wait_all, bool intr,
	137	unsigned long timeout);
	138
	139	bool reservation_object_test_signaled_rcu(struct reservation_object *obj,
	140	bool test_all);
	141
786d7257	142	#endif /* _LINUX_RESERVATION_H */