1/*
2 * Copyright 2007 Nouveau Project
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 shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
18 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
19 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20 * SOFTWARE.
21 */
22
23#include <stdlib.h>
24#include <errno.h>
25
26#include "nouveau_heap.h"
27
28int
29nouveau_heap_init(struct nouveau_heap **heap,
30                  unsigned start, unsigned size)
31{
32	struct nouveau_heap *r;
33
34	r = calloc(1, sizeof(struct nouveau_heap));
35	if (!r)
36		return 1;
37
38	r->start = start;
39	r->size  = size;
40	*heap = r;
41	return 0;
42}
43
44void
45nouveau_heap_destroy(struct nouveau_heap **heap)
46{
47	if (!*heap)
48		return;
49	free(*heap);
50	*heap = NULL;
51}
52
53int
54nouveau_heap_alloc(struct nouveau_heap *heap, unsigned size, void *priv,
55                   struct nouveau_heap **res)
56{
57	struct nouveau_heap *r;
58
59	if (!heap || !size || !res || *res)
60		return 1;
61
62	while (heap) {
63		if (!heap->in_use && heap->size >= size) {
64			r = calloc(1, sizeof(struct nouveau_heap));
65			if (!r)
66				return 1;
67
68			r->start  = (heap->start + heap->size) - size;
69			r->size   = size;
70			r->in_use = 1;
71			r->priv   = priv;
72
73			heap->size -= size;
74
75			r->next = heap->next;
76			if (heap->next)
77				heap->next->prev = r;
78			r->prev = heap;
79			heap->next = r;
80
81			*res = r;
82			return 0;
83		}
84
85		heap = heap->next;
86	}
87
88	return 1;
89}
90
91void
92nouveau_heap_free(struct nouveau_heap **res)
93{
94	struct nouveau_heap *r;
95
96	if (!res || !*res)
97		return;
98	r = *res;
99	*res = NULL;
100
101	r->in_use = 0;
102
103	if (r->next && !r->next->in_use) {
104		struct nouveau_heap *new = r->next;
105
106		new->prev = r->prev;
107		if (r->prev)
108			r->prev->next = new;
109		new->size += r->size;
110		new->start = r->start;
111
112		free(r);
113		r = new;
114	}
115
116	if (r->prev && !r->prev->in_use) {
117		r->prev->next = r->next;
118		if (r->next)
119			r->next->prev = r->prev;
120		r->prev->size += r->size;
121		free(r);
122	}
123}
124