1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/* $OpenBSD: alloc.c,v 1.3 2003/10/16 04:30:09 drahn Exp $ */
/* $NetBSD: alloc.c,v 1.1 1997/04/16 20:29:16 thorpej Exp $ */
/*
* Copyright (c) 1997 Jason R. Thorpe. All rights reserved.
* Copyright (c) 1997 Christopher G. Demetriou. All rights reserved.
* Copyright (c) 1996
* Matthias Drochner. All rights reserved.
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Dynamic memory allocator suitable for use with OpenFirmware.
*
* Compile options:
*
* ALLOC_TRACE enable tracing of allocations/deallocations
*
* ALLOC_FIRST_FIT use a first-fit allocation algorithm, rather than
* the default best-fit algorithm.
*
* DEBUG enable debugging sanity checks.
*/
#include <sys/param.h>
#include <sys/queue.h>
#include <lib/libsa/stand.h>
#include <macppc/stand/openfirm.h>
/*
* Each block actually has ALIGN(struct ml) + ALIGN(size) bytes allocated
* to it, as follows:
*
* 0 ... (sizeof(struct ml) - 1)
* allocated or unallocated: holds size of user-data part of block.
*
* sizeof(struct ml) ... (ALIGN(sizeof(struct ml)) - 1)
* allocated: unused
* unallocated: depends on packing of struct fl
*
* ALIGN(sizeof(struct ml)) ... (ALIGN(sizeof(struct ml)) +
* ALIGN(data size) - 1)
* allocated: user data
* unallocated: depends on packing of struct fl
*
* 'next' is only used when the block is unallocated (i.e. on the free list).
* However, note that ALIGN(sizeof(struct ml)) + ALIGN(data size) must
* be at least 'sizeof(struct fl)', so that blocks can be used as structures
* when on the free list.
*/
/*
* Memory lists.
*/
struct ml {
unsigned size;
LIST_ENTRY(ml) list;
};
/* XXX - this is from NetBSD */
#define LIST_HEAD_INITIALIZER(head) { NULL }
LIST_HEAD(, ml) freelist = LIST_HEAD_INITIALIZER(freelist);
LIST_HEAD(, ml) allocatedlist = LIST_HEAD_INITIALIZER(allocatedlist);
#define OVERHEAD ALIGN(sizeof (struct ml)) /* shorthand */
void *
alloc(unsigned size)
{
struct ml *f, *bestf;
unsigned bestsize = 0xffffffff; /* greater than any real size */
char *help;
int failed;
#ifdef ALLOC_TRACE
printf("alloc(%u)", size);
#endif
/*
* Account for overhead now, so that we don't get an
* "exact fit" which doesn't have enough space.
*/
size = ALIGN(size) + OVERHEAD;
#ifdef ALLOC_FIRST_FIT
/* scan freelist */
for (f = freelist.lh_first; f != NULL && f->size < size;
f = f->list.le_next)
/* noop */ ;
bestf = f;
failed = (bestf == (struct fl *)0);
#else
/* scan freelist */
f = freelist.lh_first;
while (f != NULL) {
if (f->size >= size) {
if (f->size == size) /* exact match */
goto found;
if (f->size < bestsize) {
/* keep best fit */
bestf = f;
bestsize = f->size;
}
}
f = f->list.le_next;
}
/* no match in freelist if bestsize unchanged */
failed = (bestsize == 0xffffffff);
#endif
if (failed) { /* nothing found */
/*
* Allocate memory from the OpenFirmware, rounded
* to page size, and record the chunk size.
*/
size = roundup(size, NBPG);
help = OF_claim(0, size, NBPG);
if (help == (char *)-1)
panic("alloc: out of memory");
f = (struct ml *)help;
f->size = size;
#ifdef ALLOC_TRACE
printf("=%lx (new chunk size %u)\n",
(u_long)(help + OVERHEAD), f->f_size);
#endif
goto out;
}
/* we take the best fit */
f = bestf;
found:
/* remove from freelist */
LIST_REMOVE(f, list);
help = (char *)f;
#ifdef ALLOC_TRACE
printf("=%lx (origsize %u)\n", (u_long)(help + OVERHEAD), f->size);
#endif
out:
/* place on allocated list */
LIST_INSERT_HEAD(&allocatedlist, f, list);
return (help + OVERHEAD);
}
void
free(void *ptr, unsigned size)
{
register struct ml *a = (struct ml *)((char *)ptr - OVERHEAD);
#ifdef ALLOC_TRACE
printf("free(%lx, %u) (origsize %u)\n", (u_long)ptr, size, a->size);
#endif
#ifdef DEBUG
if (size > a->size)
printf("free %u bytes @%lx, should be <=%u\n",
size, (u_long)ptr, a->size);
#endif
/* Remove from allocated list, place on freelist. */
LIST_REMOVE(a, list);
LIST_INSERT_HEAD(&freelist, a, list);
}
void
freeall()
{
#ifdef __notyet__ /* Firmware bug ?! */
struct ml *m;
/* Release chunks on freelist... */
while ((m = freelist.lh_first) != NULL) {
LIST_REMOVE(m, list);
OF_release(m, m->size);
}
/* ...and allocated list. */
while ((m = allocatedlist.lh_first) != NULL) {
LIST_REMOVE(m, list);
OF_release(m, m->size);
}
#endif /* __notyet__ */
}
|
