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
32struct 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 */
39struct 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 * @ev_fd_list: List of registered eventfd.
58 */
59 struct list_head ev_fd_list;
60 /**
61 * @lock: Protects &cb_list and &ev_fd_list, and write-locks &fence.
62 */
63 spinlock_t lock;
64 /**
65 * @file: A file backing for this syncobj.
66 */
67 struct file *file;
68};
69
70void drm_syncobj_free(struct kref *kref);
71
72/**
73 * drm_syncobj_get - acquire a syncobj reference
74 * @obj: sync object
75 *
76 * This acquires an additional reference to @obj. It is illegal to call this
77 * without already holding a reference. No locks required.
78 */
79static inline void
80drm_syncobj_get(struct drm_syncobj *obj)
81{
82 kref_get(kref: &obj->refcount);
83}
84
85/**
86 * drm_syncobj_put - release a reference to a sync object.
87 * @obj: sync object.
88 */
89static inline void
90drm_syncobj_put(struct drm_syncobj *obj)
91{
92 kref_put(kref: &obj->refcount, release: drm_syncobj_free);
93}
94
95/**
96 * drm_syncobj_fence_get - get a reference to a fence in a sync object
97 * @syncobj: sync object.
98 *
99 * This acquires additional reference to &drm_syncobj.fence contained in @obj,
100 * if not NULL. It is illegal to call this without already holding a reference.
101 * No locks required.
102 *
103 * Returns:
104 * Either the fence of @obj or NULL if there's none.
105 */
106static inline struct dma_fence *
107drm_syncobj_fence_get(struct drm_syncobj *syncobj)
108{
109 struct dma_fence *fence;
110
111 rcu_read_lock();
112 fence = dma_fence_get_rcu_safe(fencep: &syncobj->fence);
113 rcu_read_unlock();
114
115 return fence;
116}
117
118struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
119 u32 handle);
120void drm_syncobj_add_point(struct drm_syncobj *syncobj,
121 struct dma_fence_chain *chain,
122 struct dma_fence *fence,
123 uint64_t point);
124void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
125 struct dma_fence *fence);
126int drm_syncobj_find_fence(struct drm_file *file_private,
127 u32 handle, u64 point, u64 flags,
128 struct dma_fence **fence);
129void drm_syncobj_free(struct kref *kref);
130int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
131 struct dma_fence *fence);
132int drm_syncobj_get_handle(struct drm_file *file_private,
133 struct drm_syncobj *syncobj, u32 *handle);
134int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd);
135
136#endif
137