1 /*
2  * fence-array: aggregates fence to be waited together
3  *
4  * Copyright (C) 2016 Collabora Ltd
5  * Copyright (C) 2016 Advanced Micro Devices, Inc.
6  * Authors:
7  *	Gustavo Padovan <[email protected]>
8  *	Christian König <[email protected]>
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License version 2 as published by
12  * the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but WITHOUT
15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17  * more details.
18  */
19 
20 #ifndef __LINUX_DMA_FENCE_ARRAY_H
21 #define __LINUX_DMA_FENCE_ARRAY_H
22 
23 #include <linux/dma-fence.h>
24 
25 /**
26  * struct dma_fence_array_cb - callback helper for fence array
27  * @cb: fence callback structure for signaling
28  * @array: reference to the parent fence array object
29  */
30 struct dma_fence_array_cb {
31 	struct dma_fence_cb cb;
32 	struct dma_fence_array *array;
33 };
34 
35 /**
36  * struct dma_fence_array - fence to represent an array of fences
37  * @base: fence base class
38  * @lock: spinlock for fence handling
39  * @num_fences: number of fences in the array
40  * @num_pending: fences in the array still pending
41  * @fences: array of the fences
42  */
43 struct dma_fence_array {
44 	struct dma_fence base;
45 
46 	spinlock_t lock;
47 	unsigned num_fences;
48 	atomic_t num_pending;
49 	struct dma_fence **fences;
50 };
51 
52 extern const struct dma_fence_ops dma_fence_array_ops;
53 
54 /**
55  * dma_fence_is_array - check if a fence is from the array subsclass
56  * @fence: fence to test
57  *
58  * Return true if it is a dma_fence_array and false otherwise.
59  */
60 static inline bool dma_fence_is_array(struct dma_fence *fence)
61 {
62 	return fence->ops == &dma_fence_array_ops;
63 }
64 
65 /**
66  * to_dma_fence_array - cast a fence to a dma_fence_array
67  * @fence: fence to cast to a dma_fence_array
68  *
69  * Returns NULL if the fence is not a dma_fence_array,
70  * or the dma_fence_array otherwise.
71  */
72 static inline struct dma_fence_array *
73 to_dma_fence_array(struct dma_fence *fence)
74 {
75 	if (fence->ops != &dma_fence_array_ops)
76 		return NULL;
77 
78 	return container_of(fence, struct dma_fence_array, base);
79 }
80 
81 struct dma_fence_array *dma_fence_array_create(int num_fences,
82 					       struct dma_fence **fences,
83 					       u64 context, unsigned seqno,
84 					       bool signal_on_any);
85 
86 bool dma_fence_match_context(struct dma_fence *fence, u64 context);
87 
88 #endif /* __LINUX_DMA_FENCE_ARRAY_H */
89