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 
28 int
nouveau_heap_init(struct nouveau_heap ** heap,unsigned start,unsigned size)29 nouveau_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 
44 void
nouveau_heap_destroy(struct nouveau_heap ** heap)45 nouveau_heap_destroy(struct nouveau_heap **heap)
46 {
47 	if (!*heap)
48 		return;
49 	free(*heap);
50 	*heap = NULL;
51 }
52 
53 int
nouveau_heap_alloc(struct nouveau_heap * heap,unsigned size,void * priv,struct nouveau_heap ** res)54 nouveau_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 
91 void
nouveau_heap_free(struct nouveau_heap ** res)92 nouveau_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