1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * Copyright (C) 2022 Advanced Micro Devices, Inc. |
4 | * Authors: |
5 | * Christian König <christian.koenig@amd.com> |
6 | */ |
7 | |
8 | #ifndef __LINUX_DMA_FENCE_UNWRAP_H |
9 | #define __LINUX_DMA_FENCE_UNWRAP_H |
10 | |
11 | struct dma_fence; |
12 | |
13 | /** |
14 | * struct dma_fence_unwrap - cursor into the container structure |
15 | * |
16 | * Should be used with dma_fence_unwrap_for_each() iterator macro. |
17 | */ |
18 | struct dma_fence_unwrap { |
19 | /** |
20 | * @chain: potential dma_fence_chain, but can be other fence as well |
21 | */ |
22 | struct dma_fence *chain; |
23 | /** |
24 | * @array: potential dma_fence_array, but can be other fence as well |
25 | */ |
26 | struct dma_fence *array; |
27 | /** |
28 | * @index: last returned index if @array is really a dma_fence_array |
29 | */ |
30 | unsigned int index; |
31 | }; |
32 | |
33 | struct dma_fence *dma_fence_unwrap_first(struct dma_fence *head, |
34 | struct dma_fence_unwrap *cursor); |
35 | struct dma_fence *dma_fence_unwrap_next(struct dma_fence_unwrap *cursor); |
36 | |
37 | /** |
38 | * dma_fence_unwrap_for_each - iterate over all fences in containers |
39 | * @fence: current fence |
40 | * @cursor: current position inside the containers |
41 | * @head: starting point for the iterator |
42 | * |
43 | * Unwrap dma_fence_chain and dma_fence_array containers and deep dive into all |
44 | * potential fences in them. If @head is just a normal fence only that one is |
45 | * returned. |
46 | */ |
47 | #define dma_fence_unwrap_for_each(fence, cursor, head) \ |
48 | for (fence = dma_fence_unwrap_first(head, cursor); fence; \ |
49 | fence = dma_fence_unwrap_next(cursor)) |
50 | |
51 | struct dma_fence *__dma_fence_unwrap_merge(unsigned int num_fences, |
52 | struct dma_fence **fences, |
53 | struct dma_fence_unwrap *cursors); |
54 | |
55 | /** |
56 | * dma_fence_unwrap_merge - unwrap and merge fences |
57 | * |
58 | * All fences given as parameters are unwrapped and merged back together as flat |
59 | * dma_fence_array. Useful if multiple containers need to be merged together. |
60 | * |
61 | * Implemented as a macro to allocate the necessary arrays on the stack and |
62 | * account the stack frame size to the caller. |
63 | * |
64 | * Returns NULL on memory allocation failure, a dma_fence object representing |
65 | * all the given fences otherwise. |
66 | */ |
67 | #define dma_fence_unwrap_merge(...) \ |
68 | ({ \ |
69 | struct dma_fence *__f[] = { __VA_ARGS__ }; \ |
70 | struct dma_fence_unwrap __c[ARRAY_SIZE(__f)]; \ |
71 | \ |
72 | __dma_fence_unwrap_merge(ARRAY_SIZE(__f), __f, __c); \ |
73 | }) |
74 | |
75 | #endif |
76 | |