xref: /freebsd/stand/libsa/zalloc_malloc.c (revision 8f76bb7dad48538c6832c2fb466a433d2a3f8cd5)
1 /*
2  * This module derived from code donated to the FreeBSD Project by
3  * Matthew Dillon <dillon@backplane.com>
4  *
5  * Copyright (c) 1998 The FreeBSD Project
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 /*
32  * MALLOC.C - malloc equivalent, runs on top of zalloc and uses sbrk
33  */
34 
35 #include "zalloc_defs.h"
36 
37 static MemPool	MallocPool;
38 
39 #ifdef DMALLOCDEBUG
40 static int MallocMax;
41 static int MallocCount;
42 
43 void mallocstats(void);
44 #endif
45 
46 #ifdef malloc
47 #undef malloc
48 #undef free
49 #endif
50 
51 static void *Malloc_align(size_t, size_t);
52 
53 #ifndef MIN
54 # define MIN(a,b) ((a) <= (b)) ? (a) : (b)
55 #endif
56 
57 void *
58 Malloc(size_t bytes, const char *file __unused, int line __unused)
59 {
60 	return (Malloc_align(bytes, 1));
61 }
62 
63 void *
64 Memalign(size_t alignment, size_t bytes, const char *file __unused,
65     int line __unused)
66 {
67 	if (alignment == 0)
68 		alignment = 1;
69 
70 	return (Malloc_align(bytes, alignment));
71 }
72 
73 static void *
74 Malloc_align(size_t bytes, size_t alignment)
75 {
76 	Guard *res;
77 
78 #ifdef USEENDGUARD
79 	bytes += MALLOCALIGN + 1;
80 #else
81 	bytes += MALLOCALIGN;
82 #endif
83 
84 	while ((res = znalloc(&MallocPool, bytes, alignment)) == NULL) {
85 		int incr = (bytes + BLKEXTENDMASK) & ~BLKEXTENDMASK;
86 		char *base;
87 
88 		if ((base = sbrk(incr)) == (char *)-1)
89 			return (NULL);
90 		zextendPool(&MallocPool, base, incr);
91 		zfree(&MallocPool, base, incr);
92 	}
93 #ifdef DMALLOCDEBUG
94 	if (++MallocCount > MallocMax)
95 		MallocMax = MallocCount;
96 #endif
97 #ifdef USEGUARD
98 	res->ga_Magic = GAMAGIC;
99 #endif
100 	res->ga_Bytes = bytes;
101 #ifdef USEENDGUARD
102 	*((signed char *)res + bytes - 1) = -2;
103 #endif
104 
105 	return ((char *)res + MALLOCALIGN);
106 }
107 
108 void
109 Free(void *ptr, const char *file, int line)
110 {
111 	size_t bytes;
112 
113 	if (ptr != NULL) {
114 		Guard *res = (void *)((char *)ptr - MALLOCALIGN);
115 
116 		if (file == NULL)
117 			file = "unknown";
118 #ifdef USEGUARD
119 		if (res->ga_Magic == GAFREE) {
120 			printf("free: duplicate free @ %p from %s:%d\n",
121 			    ptr, file, line);
122 			return;
123 		}
124 		if (res->ga_Magic != GAMAGIC) {
125 			size_t dump_bytes;
126 
127 			dump_bytes = MIN((ptr - MallocPool.mp_Base), 512);
128 			hexdump(ptr - dump_bytes, dump_bytes);
129 			panic("free: guard1 fail @ %p from %s:%d",
130 			    ptr, file, line);
131 		}
132 		res->ga_Magic = GAFREE;
133 #endif
134 #ifdef USEENDGUARD
135 		if (*((signed char *)res + res->ga_Bytes - 1) == -1) {
136 			printf("free: duplicate2 free @ %p from %s:%d\n",
137 			    ptr, file, line);
138 			return;
139 		}
140 		if (*((signed char *)res + res->ga_Bytes - 1) != -2)
141 			panic("free: guard2 fail @ %p + %zu from %s:%d",
142 			    ptr, res->ga_Bytes - MALLOCALIGN, file, line);
143 		*((signed char *)res + res->ga_Bytes - 1) = -1;
144 #endif
145 
146 		bytes = res->ga_Bytes;
147 		zfree(&MallocPool, res, bytes);
148 #ifdef DMALLOCDEBUG
149 		--MallocCount;
150 #endif
151 	}
152 }
153 
154 
155 void *
156 Calloc(size_t n1, size_t n2, const char *file, int line)
157 {
158 	uintptr_t bytes = (uintptr_t)n1 * (uintptr_t)n2;
159 	void *res;
160 
161 	if ((res = Malloc(bytes, file, line)) != NULL) {
162 		bzero(res, bytes);
163 #ifdef DMALLOCDEBUG
164 		if (++MallocCount > MallocMax)
165 			MallocMax = MallocCount;
166 #endif
167 	}
168 	return (res);
169 }
170 
171 /*
172  * realloc() - I could be fancier here and free the old buffer before
173  *	       allocating the new one (saving potential fragmentation
174  *	       and potential buffer copies).  But I don't bother.
175  */
176 
177 void *
178 Realloc(void *ptr, size_t size, const char *file, int line)
179 {
180 	void *res;
181 	size_t old;
182 
183 	if ((res = Malloc(size, file, line)) != NULL) {
184 		if (ptr != NULL) {
185 			Guard *g = (Guard *)((char *)ptr - MALLOCALIGN);
186 
187 			old = g->ga_Bytes - MALLOCALIGN;
188 			if (old < size)
189 				bcopy(ptr, res, old);
190 			else
191 				bcopy(ptr, res, size);
192 			Free(ptr, file, line);
193 		} else {
194 #ifdef DMALLOCDEBUG
195 			if (++MallocCount > MallocMax)
196 				MallocMax = MallocCount;
197 #ifdef EXITSTATS
198 			if (DidAtExit == 0) {
199 				DidAtExit = 1;
200 				atexit(mallocstats);
201 			}
202 #endif
203 #endif
204 		}
205 	}
206 	return (res);
207 }
208 
209 void *
210 Reallocf(void *ptr, size_t size, const char *file, int line)
211 {
212 	void *res;
213 
214 	if ((res = Realloc(ptr, size, file, line)) == NULL)
215 		Free(ptr, file, line);
216 	return (res);
217 }
218 
219 #ifdef DMALLOCDEBUG
220 
221 void
222 mallocstats(void)
223 {
224 	printf("Active Allocations: %d/%d\n", MallocCount, MallocMax);
225 #ifdef ZALLOCDEBUG
226 	zallocstats(&MallocPool);
227 #endif
228 }
229 
230 #endif
231