1 // SPDX-License-Identifier: MIT
2 
3 /*
4  * Copyright © 2019 Intel Corporation
5  */
6 
7 #include "i915_sw_fence_work.h"
8 
9 static void fence_complete(struct dma_fence_work *f)
10 {
11 	if (f->ops->release)
12 		f->ops->release(f);
13 	dma_fence_signal(&f->dma);
14 }
15 
16 static void fence_work(struct work_struct *work)
17 {
18 	struct dma_fence_work *f = container_of(work, typeof(*f), work);
19 
20 	f->ops->work(f);
21 
22 	fence_complete(f);
23 	dma_fence_put(&f->dma);
24 }
25 
26 static int
27 fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
28 {
29 	struct dma_fence_work *f = container_of(fence, typeof(*f), chain);
30 
31 	switch (state) {
32 	case FENCE_COMPLETE:
33 		if (fence->error)
34 			dma_fence_set_error(&f->dma, fence->error);
35 
36 		if (!f->dma.error) {
37 			dma_fence_get(&f->dma);
38 			if (test_bit(DMA_FENCE_WORK_IMM, &f->dma.flags))
39 				fence_work(&f->work);
40 			else
41 				queue_work(system_unbound_wq, &f->work);
42 		} else {
43 			fence_complete(f);
44 		}
45 		break;
46 
47 	case FENCE_FREE:
48 		dma_fence_put(&f->dma);
49 		break;
50 	}
51 
52 	return NOTIFY_DONE;
53 }
54 
55 static const char *get_driver_name(struct dma_fence *fence)
56 {
57 	return "dma-fence";
58 }
59 
60 static const char *get_timeline_name(struct dma_fence *fence)
61 {
62 	struct dma_fence_work *f = container_of(fence, typeof(*f), dma);
63 
64 	return f->ops->name ?: "work";
65 }
66 
67 static void fence_release(struct dma_fence *fence)
68 {
69 	struct dma_fence_work *f = container_of(fence, typeof(*f), dma);
70 
71 	i915_sw_fence_fini(&f->chain);
72 
73 	BUILD_BUG_ON(offsetof(typeof(*f), dma));
74 	dma_fence_free(&f->dma);
75 }
76 
77 static const struct dma_fence_ops fence_ops = {
78 	.get_driver_name = get_driver_name,
79 	.get_timeline_name = get_timeline_name,
80 	.release = fence_release,
81 };
82 
83 void dma_fence_work_init(struct dma_fence_work *f,
84 			 const struct dma_fence_work_ops *ops)
85 {
86 	f->ops = ops;
87 	spin_lock_init(&f->lock);
88 	dma_fence_init(&f->dma, &fence_ops, &f->lock, 0, 0);
89 	i915_sw_fence_init(&f->chain, fence_notify);
90 	INIT_WORK(&f->work, fence_work);
91 }
92 
93 int dma_fence_work_chain(struct dma_fence_work *f, struct dma_fence *signal)
94 {
95 	if (!signal)
96 		return 0;
97 
98 	return __i915_sw_fence_await_dma_fence(&f->chain, signal, &f->cb);
99 }
100