1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * fence-array: aggregates fence to be waited together
4 *
5 * Copyright (C) 2016 Collabora Ltd
6 * Copyright (C) 2016 Advanced Micro Devices, Inc.
7 * Authors:
8 *	Gustavo Padovan <gustavo@padovan.org>
9 *	Christian K��nig <christian.koenig@amd.com>
10 */
11
12#ifndef __LINUX_DMA_FENCE_ARRAY_H
13#define __LINUX_DMA_FENCE_ARRAY_H
14
15#include <linux/dma-fence.h>
16#include <linux/irq_work.h>
17
18/**
19 * struct dma_fence_array_cb - callback helper for fence array
20 * @cb: fence callback structure for signaling
21 * @array: reference to the parent fence array object
22 */
23struct dma_fence_array_cb {
24	struct dma_fence_cb cb;
25	struct dma_fence_array *array;
26};
27
28/**
29 * struct dma_fence_array - fence to represent an array of fences
30 * @base: fence base class
31 * @lock: spinlock for fence handling
32 * @num_fences: number of fences in the array
33 * @num_pending: fences in the array still pending
34 * @fences: array of the fences
35 * @work: internal irq_work function
36 */
37struct dma_fence_array {
38	struct dma_fence base;
39
40	spinlock_t lock;
41	unsigned num_fences;
42	atomic_t num_pending;
43	struct dma_fence **fences;
44
45	struct irq_work work;
46};
47
48/**
49 * to_dma_fence_array - cast a fence to a dma_fence_array
50 * @fence: fence to cast to a dma_fence_array
51 *
52 * Returns NULL if the fence is not a dma_fence_array,
53 * or the dma_fence_array otherwise.
54 */
55static inline struct dma_fence_array *
56to_dma_fence_array(struct dma_fence *fence)
57{
58	if (!fence || !dma_fence_is_array(fence))
59		return NULL;
60
61	return container_of(fence, struct dma_fence_array, base);
62}
63
64/**
65 * dma_fence_array_for_each - iterate over all fences in array
66 * @fence: current fence
67 * @index: index into the array
68 * @head: potential dma_fence_array object
69 *
70 * Test if @array is a dma_fence_array object and if yes iterate over all fences
71 * in the array. If not just iterate over the fence in @array itself.
72 *
73 * For a deep dive iterator see dma_fence_unwrap_for_each().
74 */
75#define dma_fence_array_for_each(fence, index, head)			\
76	for (index = 0, fence = dma_fence_array_first(head); fence;	\
77	     ++(index), fence = dma_fence_array_next(head, index))
78
79struct dma_fence_array *dma_fence_array_create(int num_fences,
80					       struct dma_fence **fences,
81					       u64 context, unsigned seqno,
82					       bool signal_on_any);
83
84bool dma_fence_match_context(struct dma_fence *fence, u64 context);
85
86struct dma_fence *dma_fence_array_first(struct dma_fence *head);
87struct dma_fence *dma_fence_array_next(struct dma_fence *head,
88				       unsigned int index);
89
90#endif /* __LINUX_DMA_FENCE_ARRAY_H */
91