1 /*
2 * GLX Hardware Device Driver common code
3 * Copyright (C) 1999 Wittawat Yamwong
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included
13 * in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * WITTAWAT YAMWONG, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM,
19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
21 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22 *
23 */
24
25 #include <stdlib.h>
26 #include <assert.h>
27
28 #include "xf86drm.h"
29 #include "mm.h"
30
mmDumpMemInfo(const struct mem_block * heap)31 void mmDumpMemInfo(const struct mem_block *heap)
32 {
33 drmMsg("Memory heap %p:\n", (void *)heap);
34 if (heap == 0) {
35 drmMsg(" heap == 0\n");
36 } else {
37 const struct mem_block *p;
38
39 for (p = heap->next; p != heap; p = p->next) {
40 drmMsg(" Offset:%08x, Size:%08x, %c%c\n", p->ofs,
41 p->size, p->free ? 'F' : '.',
42 p->reserved ? 'R' : '.');
43 }
44
45 drmMsg("\nFree list:\n");
46
47 for (p = heap->next_free; p != heap; p = p->next_free) {
48 drmMsg(" FREE Offset:%08x, Size:%08x, %c%c\n", p->ofs,
49 p->size, p->free ? 'F' : '.',
50 p->reserved ? 'R' : '.');
51 }
52
53 }
54 drmMsg("End of memory blocks\n");
55 }
56
mmInit(int ofs,int size)57 struct mem_block *mmInit(int ofs, int size)
58 {
59 struct mem_block *heap, *block;
60
61 if (size <= 0)
62 return NULL;
63
64 heap = (struct mem_block *)calloc(1, sizeof(struct mem_block));
65 if (!heap)
66 return NULL;
67
68 block = (struct mem_block *)calloc(1, sizeof(struct mem_block));
69 if (!block) {
70 free(heap);
71 return NULL;
72 }
73
74 heap->next = block;
75 heap->prev = block;
76 heap->next_free = block;
77 heap->prev_free = block;
78
79 block->heap = heap;
80 block->next = heap;
81 block->prev = heap;
82 block->next_free = heap;
83 block->prev_free = heap;
84
85 block->ofs = ofs;
86 block->size = size;
87 block->free = 1;
88
89 return heap;
90 }
91
SliceBlock(struct mem_block * p,int startofs,int size,int reserved,int alignment)92 static struct mem_block *SliceBlock(struct mem_block *p,
93 int startofs, int size,
94 int reserved, int alignment)
95 {
96 struct mem_block *newblock;
97
98 /* break left [p, newblock, p->next], then p = newblock */
99 if (startofs > p->ofs) {
100 newblock =
101 (struct mem_block *)calloc(1, sizeof(struct mem_block));
102 if (!newblock)
103 return NULL;
104 newblock->ofs = startofs;
105 newblock->size = p->size - (startofs - p->ofs);
106 newblock->free = 1;
107 newblock->heap = p->heap;
108
109 newblock->next = p->next;
110 newblock->prev = p;
111 p->next->prev = newblock;
112 p->next = newblock;
113
114 newblock->next_free = p->next_free;
115 newblock->prev_free = p;
116 p->next_free->prev_free = newblock;
117 p->next_free = newblock;
118
119 p->size -= newblock->size;
120 p = newblock;
121 }
122
123 /* break right, also [p, newblock, p->next] */
124 if (size < p->size) {
125 newblock =
126 (struct mem_block *)calloc(1, sizeof(struct mem_block));
127 if (!newblock)
128 return NULL;
129 newblock->ofs = startofs + size;
130 newblock->size = p->size - size;
131 newblock->free = 1;
132 newblock->heap = p->heap;
133
134 newblock->next = p->next;
135 newblock->prev = p;
136 p->next->prev = newblock;
137 p->next = newblock;
138
139 newblock->next_free = p->next_free;
140 newblock->prev_free = p;
141 p->next_free->prev_free = newblock;
142 p->next_free = newblock;
143
144 p->size = size;
145 }
146
147 /* p = middle block */
148 p->free = 0;
149
150 /* Remove p from the free list:
151 */
152 p->next_free->prev_free = p->prev_free;
153 p->prev_free->next_free = p->next_free;
154
155 p->next_free = 0;
156 p->prev_free = 0;
157
158 p->reserved = reserved;
159 return p;
160 }
161
mmAllocMem(struct mem_block * heap,int size,int align2,int startSearch)162 struct mem_block *mmAllocMem(struct mem_block *heap, int size, int align2,
163 int startSearch)
164 {
165 struct mem_block *p;
166 const int mask = (1 << align2) - 1;
167 int startofs = 0;
168 int endofs;
169
170 if (!heap || align2 < 0 || size <= 0)
171 return NULL;
172
173 for (p = heap->next_free; p != heap; p = p->next_free) {
174 assert(p->free);
175
176 startofs = (p->ofs + mask) & ~mask;
177 if (startofs < startSearch) {
178 startofs = startSearch;
179 }
180 endofs = startofs + size;
181 if (endofs <= (p->ofs + p->size))
182 break;
183 }
184
185 if (p == heap)
186 return NULL;
187
188 assert(p->free);
189 p = SliceBlock(p, startofs, size, 0, mask + 1);
190
191 return p;
192 }
193
mmFindBlock(struct mem_block * heap,int start)194 struct mem_block *mmFindBlock(struct mem_block *heap, int start)
195 {
196 struct mem_block *p;
197
198 for (p = heap->next; p != heap; p = p->next) {
199 if (p->ofs == start)
200 return p;
201 }
202
203 return NULL;
204 }
205
Join2Blocks(struct mem_block * p)206 static int Join2Blocks(struct mem_block *p)
207 {
208 /* XXX there should be some assertions here */
209
210 /* NOTE: heap->free == 0 */
211
212 if (p->free && p->next->free) {
213 struct mem_block *q = p->next;
214
215 assert(p->ofs + p->size == q->ofs);
216 p->size += q->size;
217
218 p->next = q->next;
219 q->next->prev = p;
220
221 q->next_free->prev_free = q->prev_free;
222 q->prev_free->next_free = q->next_free;
223
224 free(q);
225 return 1;
226 }
227 return 0;
228 }
229
mmFreeMem(struct mem_block * b)230 int mmFreeMem(struct mem_block *b)
231 {
232 if (!b)
233 return 0;
234
235 if (b->free) {
236 drmMsg("block already free\n");
237 return -1;
238 }
239 if (b->reserved) {
240 drmMsg("block is reserved\n");
241 return -1;
242 }
243
244 b->free = 1;
245 b->next_free = b->heap->next_free;
246 b->prev_free = b->heap;
247 b->next_free->prev_free = b;
248 b->prev_free->next_free = b;
249
250 Join2Blocks(b);
251 if (b->prev != b->heap)
252 Join2Blocks(b->prev);
253
254 return 0;
255 }
256
mmDestroy(struct mem_block * heap)257 void mmDestroy(struct mem_block *heap)
258 {
259 struct mem_block *p;
260
261 if (!heap)
262 return;
263
264 for (p = heap->next; p != heap;) {
265 struct mem_block *next = p->next;
266 free(p);
267 p = next;
268 }
269
270 free(heap);
271 }
272