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 #include <linux/irq_work.h>
25 
26 /**
27  * struct dma_fence_array_cb - callback helper for fence array
28  * @cb: fence callback structure for signaling
29  * @array: reference to the parent fence array object
30  */
31 struct dma_fence_array_cb {
32 	struct dma_fence_cb cb;
33 	struct dma_fence_array *array;
34 };
35 
36 /**
37  * struct dma_fence_array - fence to represent an array of fences
38  * @base: fence base class
39  * @lock: spinlock for fence handling
40  * @num_fences: number of fences in the array
41  * @num_pending: fences in the array still pending
42  * @fences: array of the fences
43  */
44 struct dma_fence_array {
45 	struct dma_fence base;
46 
47 	spinlock_t lock;
48 	unsigned num_fences;
49 	atomic_t num_pending;
50 	struct dma_fence **fences;
51 
52 	struct irq_work work;
53 };
54 
55 extern const struct dma_fence_ops dma_fence_array_ops;
56 
57 /**
58  * dma_fence_is_array - check if a fence is from the array subsclass
59  * @fence: fence to test
60  *
61  * Return true if it is a dma_fence_array and false otherwise.
62  */
63 static inline bool dma_fence_is_array(struct dma_fence *fence)
64 {
65 	return fence->ops == &dma_fence_array_ops;
66 }
67 
68 /**
69  * to_dma_fence_array - cast a fence to a dma_fence_array
70  * @fence: fence to cast to a dma_fence_array
71  *
72  * Returns NULL if the fence is not a dma_fence_array,
73  * or the dma_fence_array otherwise.
74  */
75 static inline struct dma_fence_array *
76 to_dma_fence_array(struct dma_fence *fence)
77 {
78 	if (fence->ops != &dma_fence_array_ops)
79 		return NULL;
80 
81 	return container_of(fence, struct dma_fence_array, base);
82 }
83 
84 struct dma_fence_array *dma_fence_array_create(int num_fences,
85 					       struct dma_fence **fences,
86 					       u64 context, unsigned seqno,
87 					       bool signal_on_any);
88 
89 bool dma_fence_match_context(struct dma_fence *fence, u64 context);
90 
91 #endif /* __LINUX_DMA_FENCE_ARRAY_H */
92