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 <assert.h>
26#include <stdio.h>
27#include <stdlib.h>
28
29#include "compiler.h"
30#include "mm.h"
31
32
33void
34mmDumpMemInfo(const struct mem_block *heap)
35{
36   fprintf(stderr, "Memory heap %p:\n", (void *)heap);
37   if (heap == 0) {
38      fprintf(stderr, "  heap == 0\n");
39   } else {
40      const struct mem_block *p;
41
42      for(p = heap->next; p != heap; p = p->next) {
43	 fprintf(stderr, "  Offset:%08x, Size:%08x, %c%c\n",p->ofs,p->size,
44		 p->free ? 'F':'.',
45		 p->reserved ? 'R':'.');
46      }
47
48      fprintf(stderr, "\nFree list:\n");
49
50      for(p = heap->next_free; p != heap; p = p->next_free) {
51	 fprintf(stderr, " FREE Offset:%08x, Size:%08x, %c%c\n",p->ofs,p->size,
52		 p->free ? 'F':'.',
53		 p->reserved ? 'R':'.');
54      }
55
56   }
57   fprintf(stderr, "End of memory blocks\n");
58}
59
60struct mem_block *
61mmInit(unsigned ofs, unsigned size)
62{
63   struct mem_block *heap, *block;
64
65   if (!size)
66      return NULL;
67
68   heap = (struct mem_block *) calloc(1, sizeof(struct mem_block));
69   if (!heap)
70      return NULL;
71
72   block = (struct mem_block *) calloc(1, sizeof(struct mem_block));
73   if (!block) {
74      free(heap);
75      return NULL;
76   }
77
78   heap->next = block;
79   heap->prev = block;
80   heap->next_free = block;
81   heap->prev_free = block;
82
83   block->heap = heap;
84   block->next = heap;
85   block->prev = heap;
86   block->next_free = heap;
87   block->prev_free = heap;
88
89   block->ofs = ofs;
90   block->size = size;
91   block->free = 1;
92
93   return heap;
94}
95
96
97static struct mem_block *
98SliceBlock(struct mem_block *p,
99           unsigned startofs, unsigned size,
100           unsigned reserved, unsigned alignment)
101{
102   struct mem_block *newblock;
103
104   /* break left  [p, newblock, p->next], then p = newblock */
105   if (startofs > p->ofs) {
106      newblock = (struct mem_block*) calloc(1, sizeof(struct mem_block));
107      if (!newblock)
108	 return NULL;
109      newblock->ofs = startofs;
110      newblock->size = p->size - (startofs - p->ofs);
111      newblock->free = 1;
112      newblock->heap = p->heap;
113
114      newblock->next = p->next;
115      newblock->prev = p;
116      p->next->prev = newblock;
117      p->next = newblock;
118
119      newblock->next_free = p->next_free;
120      newblock->prev_free = p;
121      p->next_free->prev_free = newblock;
122      p->next_free = newblock;
123
124      p->size -= newblock->size;
125      p = newblock;
126   }
127
128   /* break right, also [p, newblock, p->next] */
129   if (size < p->size) {
130      newblock = (struct mem_block*) calloc(1, sizeof(struct mem_block));
131      if (!newblock)
132	 return NULL;
133      newblock->ofs = startofs + size;
134      newblock->size = p->size - size;
135      newblock->free = 1;
136      newblock->heap = p->heap;
137
138      newblock->next = p->next;
139      newblock->prev = p;
140      p->next->prev = newblock;
141      p->next = newblock;
142
143      newblock->next_free = p->next_free;
144      newblock->prev_free = p;
145      p->next_free->prev_free = newblock;
146      p->next_free = newblock;
147
148      p->size = size;
149   }
150
151   /* p = middle block */
152   p->free = 0;
153
154   /* Remove p from the free list:
155    */
156   p->next_free->prev_free = p->prev_free;
157   p->prev_free->next_free = p->next_free;
158
159   p->next_free = 0;
160   p->prev_free = 0;
161
162   p->reserved = reserved;
163   return p;
164}
165
166
167struct mem_block *
168mmAllocMem(struct mem_block *heap, unsigned size, unsigned align2, unsigned startSearch)
169{
170   struct mem_block *p;
171   const unsigned mask = (1 << align2)-1;
172   unsigned startofs = 0;
173   unsigned endofs;
174
175   if (!heap || !size)
176      return NULL;
177
178   for (p = heap->next_free; p != heap; p = p->next_free) {
179      assert(p->free);
180
181      startofs = (p->ofs + mask) & ~mask;
182      if ( startofs < startSearch ) {
183	 startofs = startSearch;
184      }
185      endofs = startofs+size;
186      if (endofs <= (p->ofs+p->size))
187	 break;
188   }
189
190   if (p == heap)
191      return NULL;
192
193   assert(p->free);
194   p = SliceBlock(p,startofs,size,0,mask+1);
195
196   return p;
197}
198
199
200struct mem_block *
201mmFindBlock(struct mem_block *heap, unsigned start)
202{
203   struct mem_block *p;
204
205   for (p = heap->next; p != heap; p = p->next) {
206      if (p->ofs == start)
207	 return p;
208   }
209
210   return NULL;
211}
212
213
214static inline int
215Join2Blocks(struct mem_block *p)
216{
217   /* XXX there should be some assertions here */
218
219   /* NOTE: heap->free == 0 */
220
221   if (p->free && p->next->free) {
222      struct mem_block *q = p->next;
223
224      assert(p->ofs + p->size == q->ofs);
225      p->size += q->size;
226
227      p->next = q->next;
228      q->next->prev = p;
229
230      q->next_free->prev_free = q->prev_free;
231      q->prev_free->next_free = q->next_free;
232
233      free(q);
234      return 1;
235   }
236   return 0;
237}
238
239int
240mmFreeMem(struct mem_block *b)
241{
242   if (!b)
243      return 0;
244
245   if (b->free) {
246      fprintf(stderr, "block already free\n");
247      return -1;
248   }
249   if (b->reserved) {
250      fprintf(stderr, "block is reserved\n");
251      return -1;
252   }
253
254   b->free = 1;
255   b->next_free = b->heap->next_free;
256   b->prev_free = b->heap;
257   b->next_free->prev_free = b;
258   b->prev_free->next_free = b;
259
260   Join2Blocks(b);
261   if (b->prev != b->heap)
262      Join2Blocks(b->prev);
263
264   return 0;
265}
266
267
268void
269mmDestroy(struct mem_block *heap)
270{
271   struct mem_block *p;
272
273   if (!heap)
274      return;
275
276   for (p = heap->next; p != heap; ) {
277      struct mem_block *next = p->next;
278      free(p);
279      p = next;
280   }
281
282   free(heap);
283}
284