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
31struct drm_file;
32
33/**
34 * struct drm_syncobj - sync object.
35 *
36 * This structure defines a generic sync object which wraps a &dma_fence.
37 */
38struct drm_syncobj {
39 /**
40 * @refcount: Reference count of this object.
41 */
42 struct kref refcount;
43 /**
44 * @fence:
45 * NULL or a pointer to the fence bound to this object.
46 *
47 * This field should not be used directly. Use drm_syncobj_fence_get()
48 * and drm_syncobj_replace_fence() instead.
49 */
50 struct dma_fence __rcu *fence;
51 /**
52 * @cb_list: List of callbacks to call when the &fence gets replaced.
53 */
54 struct list_head cb_list;
55 /**
56 * @lock: Protects &cb_list and write-locks &fence.
57 */
58 spinlock_t lock;
59 /**
60 * @file: A file backing for this syncobj.
61 */
62 struct file *file;
63};
64
65void drm_syncobj_free(struct kref *kref);
66
67/**
68 * drm_syncobj_get - acquire a syncobj reference
69 * @obj: sync object
70 *
71 * This acquires an additional reference to @obj. It is illegal to call this
72 * without already holding a reference. No locks required.
73 */
74static inline void
75drm_syncobj_get(struct drm_syncobj *obj)
76{
77 kref_get(&obj->refcount);
78}
79
80/**
81 * drm_syncobj_put - release a reference to a sync object.
82 * @obj: sync object.
83 */
84static inline void
85drm_syncobj_put(struct drm_syncobj *obj)
86{
87 kref_put(&obj->refcount, drm_syncobj_free);
88}
89
90/**
91 * drm_syncobj_fence_get - get a reference to a fence in a sync object
92 * @syncobj: sync object.
93 *
94 * This acquires additional reference to &drm_syncobj.fence contained in @obj,
95 * if not NULL. It is illegal to call this without already holding a reference.
96 * No locks required.
97 *
98 * Returns:
99 * Either the fence of @obj or NULL if there's none.
100 */
101static inline struct dma_fence *
102drm_syncobj_fence_get(struct drm_syncobj *syncobj)
103{
104 struct dma_fence *fence;
105
106 rcu_read_lock();
107 fence = dma_fence_get_rcu_safe(&syncobj->fence);
108 rcu_read_unlock();
109
110 return fence;
111}
112
113struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
114 u32 handle);
115void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
116 struct dma_fence *fence);
117int drm_syncobj_find_fence(struct drm_file *file_private,
118 u32 handle, u64 point, u64 flags,
119 struct dma_fence **fence);
120void drm_syncobj_free(struct kref *kref);
121int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
122 struct dma_fence *fence);
123int drm_syncobj_get_handle(struct drm_file *file_private,
124 struct drm_syncobj *syncobj, u32 *handle);
125int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd);
126
127#endif
128