1/*
2 * Copyright �� 2017 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 */
24
25#include "lib_sw_fence.h"
26
27/* Small library of different fence types useful for writing tests */
28
29static int
30nop_fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
31{
32	return NOTIFY_DONE;
33}
34
35void __onstack_fence_init(struct i915_sw_fence *fence,
36			  const char *name,
37			  struct lock_class_key *key)
38{
39	debug_fence_init_onstack(fence);
40
41	__init_waitqueue_head(&fence->wait, name, key);
42	atomic_set(&fence->pending, 1);
43	fence->error = 0;
44	fence->fn = nop_fence_notify;
45}
46
47void onstack_fence_fini(struct i915_sw_fence *fence)
48{
49	if (!fence->fn)
50		return;
51
52	i915_sw_fence_commit(fence);
53	i915_sw_fence_fini(fence);
54}
55
56static void timed_fence_wake(struct timer_list *t)
57{
58	struct timed_fence *tf = from_timer(tf, t, timer);
59
60	i915_sw_fence_commit(&tf->fence);
61}
62
63void timed_fence_init(struct timed_fence *tf, unsigned long expires)
64{
65	onstack_fence_init(&tf->fence);
66
67	timer_setup_on_stack(&tf->timer, timed_fence_wake, 0);
68
69	if (time_after(expires, jiffies))
70		mod_timer(&tf->timer, expires);
71	else
72		i915_sw_fence_commit(&tf->fence);
73}
74
75void timed_fence_fini(struct timed_fence *tf)
76{
77	if (del_timer_sync(&tf->timer))
78		i915_sw_fence_commit(&tf->fence);
79
80	destroy_timer_on_stack(&tf->timer);
81	i915_sw_fence_fini(&tf->fence);
82}
83
84struct heap_fence {
85	struct i915_sw_fence fence;
86	union {
87		struct kref ref;
88		struct rcu_head rcu;
89	};
90};
91
92static int
93heap_fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
94{
95	struct heap_fence *h = container_of(fence, typeof(*h), fence);
96
97	switch (state) {
98	case FENCE_COMPLETE:
99		break;
100
101	case FENCE_FREE:
102		heap_fence_put(&h->fence);
103	}
104
105	return NOTIFY_DONE;
106}
107
108struct i915_sw_fence *heap_fence_create(gfp_t gfp)
109{
110	struct heap_fence *h;
111
112	h = kmalloc(sizeof(*h), gfp);
113	if (!h)
114		return NULL;
115
116	i915_sw_fence_init(&h->fence, heap_fence_notify);
117	refcount_set(&h->ref.refcount, 2);
118
119	return &h->fence;
120}
121
122static void heap_fence_release(struct kref *ref)
123{
124	struct heap_fence *h = container_of(ref, typeof(*h), ref);
125
126	i915_sw_fence_fini(&h->fence);
127
128	kfree_rcu(h, rcu);
129}
130
131void heap_fence_put(struct i915_sw_fence *fence)
132{
133	struct heap_fence *h = container_of(fence, typeof(*h), fence);
134
135	kref_put(&h->ref, heap_fence_release);
136}
137