1 /*
2 * Copyright © 2017 Red Hat
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 *
25 */
26 #ifndef __DRM_SYNCOBJ_H__
27 #define __DRM_SYNCOBJ_H__
28
29 #include <linux/dma-fence.h>
30 #include <linux/dma-fence-chain.h>
31
32 struct drm_file;
33
34 /**
35 * struct drm_syncobj - sync object.
36 *
37 * This structure defines a generic sync object which wraps a &dma_fence.
38 */
39 struct drm_syncobj {
40 /**
41 * @refcount: Reference count of this object.
42 */
43 struct kref refcount;
44 /**
45 * @fence:
46 * NULL or a pointer to the fence bound to this object.
47 *
48 * This field should not be used directly. Use drm_syncobj_fence_get()
49 * and drm_syncobj_replace_fence() instead.
50 */
51 struct dma_fence __rcu *fence;
52 /**
53 * @cb_list: List of callbacks to call when the &fence gets replaced.
54 */
55 struct list_head cb_list;
56 /**
57 * @lock: Protects &cb_list and write-locks &fence.
58 */
59 spinlock_t lock;
60 /**
61 * @file: A file backing for this syncobj.
62 */
63 struct file *file;
64 };
65
66 void drm_syncobj_free(struct kref *kref);
67
68 /**
69 * drm_syncobj_get - acquire a syncobj reference
70 * @obj: sync object
71 *
72 * This acquires an additional reference to @obj. It is illegal to call this
73 * without already holding a reference. No locks required.
74 */
75 static inline void
76 drm_syncobj_get(struct drm_syncobj *obj)
77 {
78 kref_get(&obj->refcount);
79 }
80
81 /**
82 * drm_syncobj_put - release a reference to a sync object.
83 * @obj: sync object.
84 */
85 static inline void
86 drm_syncobj_put(struct drm_syncobj *obj)
87 {
88 kref_put(&obj->refcount, drm_syncobj_free);
89 }
90
91 /**
92 * drm_syncobj_fence_get - get a reference to a fence in a sync object
93 * @syncobj: sync object.
94 *
95 * This acquires additional reference to &drm_syncobj.fence contained in @obj,
96 * if not NULL. It is illegal to call this without already holding a reference.
97 * No locks required.
98 *
99 * Returns:
100 * Either the fence of @obj or NULL if there's none.
101 */
102 static inline struct dma_fence *
103 drm_syncobj_fence_get(struct drm_syncobj *syncobj)
104 {
105 struct dma_fence *fence;
106
107 rcu_read_lock();
108 fence = dma_fence_get_rcu_safe(&syncobj->fence);
109 rcu_read_unlock();
110
111 return fence;
112 }
113
114 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
115 u32 handle);
116 void drm_syncobj_add_point(struct drm_syncobj *syncobj,
117 struct dma_fence_chain *chain,
118 struct dma_fence *fence,
119 uint64_t point);
120 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
121 struct dma_fence *fence);
122 int drm_syncobj_find_fence(struct drm_file *file_private,
123 u32 handle, u64 point, u64 flags,
124 struct dma_fence **fence);
125 void drm_syncobj_free(struct kref *kref);
126 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
127 struct dma_fence *fence);
128 int drm_syncobj_get_handle(struct drm_file *file_private,
129 struct drm_syncobj *syncobj, u32 *handle);
130 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd);
131
132 #endif