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 __i915_sw_fence_call
 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->flags = (unsigned long)nop_fence_notify;
 45}
 46
 47void onstack_fence_fini(struct i915_sw_fence *fence)
 48{
 49	if (!fence->flags)
 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 __i915_sw_fence_call
 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}