2 * Header file for reservations for dma-buf and ttm
4 * Copyright(C) 2011 Linaro Limited. All rights reserved.
5 * Copyright (C) 2012-2013 Canonical Ltd
6 * Copyright (C) 2012 Texas Instruments
9 * Rob Clark <robdclark@gmail.com>
10 * Maarten Lankhorst <maarten.lankhorst@canonical.com>
11 * Thomas Hellstrom <thellstrom-at-vmware-dot-com>
13 * Based on bo.c which bears the following copyright notice,
14 * but is dual licensed:
16 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
17 * All Rights Reserved.
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:
27 * The above copyright notice and this permission notice (including the
28 * next paragraph) shall be included in all copies or substantial portions
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.
39 #ifndef _LINUX_RESERVATION_H
40 #define _LINUX_RESERVATION_H
42 #include <linux/ww_mutex.h>
43 #include <linux/fence.h>
44 #include <linux/slab.h>
45 #include <linux/seqlock.h>
46 #include <linux/rcupdate.h>
48 extern struct ww_class reservation_ww_class
;
49 extern struct lock_class_key reservation_seqcount_class
;
50 extern const char reservation_seqcount_string
[];
52 struct reservation_object_list
{
54 u32 shared_count
, shared_max
;
55 struct fence __rcu
*shared
[];
58 struct reservation_object
{
62 struct fence __rcu
*fence_excl
;
63 struct reservation_object_list __rcu
*fence
;
64 struct reservation_object_list
*staged
;
67 #define reservation_object_held(obj) lockdep_is_held(&(obj)->lock.base)
68 #define reservation_object_assert_held(obj) \
69 lockdep_assert_held(&(obj)->lock.base)
72 reservation_object_init(struct reservation_object
*obj
)
74 ww_mutex_init(&obj
->lock
, &reservation_ww_class
);
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
);
83 reservation_object_fini(struct reservation_object
*obj
)
86 struct reservation_object_list
*fobj
;
90 * This object should be dead and all references must have
91 * been released to it, so no need to be protected with rcu.
93 excl
= rcu_dereference_protected(obj
->fence_excl
, 1);
97 fobj
= rcu_dereference_protected(obj
->fence
, 1);
99 for (i
= 0; i
< fobj
->shared_count
; ++i
)
100 fence_put(rcu_dereference_protected(fobj
->shared
[i
], 1));
106 ww_mutex_destroy(&obj
->lock
);
109 static inline struct reservation_object_list
*
110 reservation_object_get_list(struct reservation_object
*obj
)
112 return rcu_dereference_protected(obj
->fence
,
113 reservation_object_held(obj
));
116 static inline struct fence
*
117 reservation_object_get_excl(struct reservation_object
*obj
)
119 return rcu_dereference_protected(obj
->fence_excl
,
120 reservation_object_held(obj
));
123 static inline struct fence
*
124 reservation_object_get_excl_rcu(struct reservation_object
*obj
)
129 seq
= read_seqcount_begin(&obj
->seq
);
131 fence
= rcu_dereference(obj
->fence_excl
);
132 if (read_seqcount_retry(&obj
->seq
, seq
)) {
136 fence
= fence_get(fence
);
141 int reservation_object_reserve_shared(struct reservation_object
*obj
);
142 void reservation_object_add_shared_fence(struct reservation_object
*obj
,
143 struct fence
*fence
);
145 void reservation_object_add_excl_fence(struct reservation_object
*obj
,
146 struct fence
*fence
);
148 int reservation_object_get_fences_rcu(struct reservation_object
*obj
,
149 struct fence
**pfence_excl
,
150 unsigned *pshared_count
,
151 struct fence
***pshared
);
153 long reservation_object_wait_timeout_rcu(struct reservation_object
*obj
,
154 bool wait_all
, bool intr
,
155 unsigned long timeout
);
157 bool reservation_object_test_signaled_rcu(struct reservation_object
*obj
,
160 #endif /* _LINUX_RESERVATION_H */