xref: /freebsd/sys/vm/uma_dbg.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson <jeff@FreeBSD.org>
5  * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
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 unmodified, this list of conditions, and the following
13  *    disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * uma_dbg.c	Debugging features for UMA users
32  *
33  */
34 
35 #include <sys/cdefs.h>
36 #include "opt_vm.h"
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/bitset.h>
41 #include <sys/kernel.h>
42 #include <sys/types.h>
43 #include <sys/queue.h>
44 #include <sys/lock.h>
45 #include <sys/mutex.h>
46 #include <sys/malloc.h>
47 
48 #include <vm/vm.h>
49 #include <vm/vm_object.h>
50 #include <vm/vm_page.h>
51 #include <vm/uma.h>
52 #include <vm/uma_int.h>
53 #include <vm/uma_dbg.h>
54 #include <vm/memguard.h>
55 
56 static const uint32_t uma_junk = 0xdeadc0de;
57 
58 /*
59  * Checks an item to make sure it hasn't been overwritten since it was freed,
60  * prior to subsequent reallocation.
61  *
62  * Complies with standard ctor arg/return
63  */
64 int
65 trash_ctor(void *mem, int size, void *arg, int flags)
66 {
67 	int cnt;
68 	uint32_t *p;
69 
70 #ifdef DEBUG_MEMGUARD
71 	if (is_memguard_addr(mem))
72 		return (0);
73 #endif
74 
75 	cnt = size / sizeof(uma_junk);
76 
77 	for (p = mem; cnt > 0; cnt--, p++)
78 		if (*p != uma_junk) {
79 #ifdef INVARIANTS
80 			panic("Memory modified after free %p(%d) val=%x @ %p\n",
81 			    mem, size, *p, p);
82 #else
83 			printf("Memory modified after free %p(%d) val=%x @ %p\n",
84 			    mem, size, *p, p);
85 #endif
86 			return (0);
87 		}
88 	return (0);
89 }
90 
91 /*
92  * Fills an item with predictable garbage
93  *
94  * Complies with standard dtor arg/return
95  *
96  */
97 void
98 trash_dtor(void *mem, int size, void *arg)
99 {
100 	int cnt;
101 	uint32_t *p;
102 
103 #ifdef DEBUG_MEMGUARD
104 	if (is_memguard_addr(mem))
105 		return;
106 #endif
107 
108 	cnt = size / sizeof(uma_junk);
109 
110 	for (p = mem; cnt > 0; cnt--, p++)
111 		*p = uma_junk;
112 }
113 
114 /*
115  * Fills an item with predictable garbage
116  *
117  * Complies with standard init arg/return
118  *
119  */
120 int
121 trash_init(void *mem, int size, int flags)
122 {
123 	trash_dtor(mem, size, NULL);
124 	return (0);
125 }
126 
127 /*
128  * Checks an item to make sure it hasn't been overwritten since it was freed.
129  *
130  * Complies with standard fini arg/return
131  *
132  */
133 void
134 trash_fini(void *mem, int size)
135 {
136 	(void)trash_ctor(mem, size, NULL, 0);
137 }
138 
139 int
140 mtrash_ctor(void *mem, int size, void *arg, int flags)
141 {
142 	struct malloc_type **ksp;
143 	uint32_t *p = mem;
144 	int cnt;
145 
146 #ifdef DEBUG_MEMGUARD
147 	if (is_memguard_addr(mem))
148 		return (0);
149 #endif
150 
151 	size -= sizeof(struct malloc_type *);
152 	ksp = (struct malloc_type **)mem;
153 	ksp += size / sizeof(struct malloc_type *);
154 	cnt = size / sizeof(uma_junk);
155 
156 	for (p = mem; cnt > 0; cnt--, p++)
157 		if (*p != uma_junk) {
158 			printf("Memory modified after free %p(%d) val=%x @ %p\n",
159 			    mem, size, *p, p);
160 			panic("Most recently used by %s\n", (*ksp == NULL)?
161 			    "none" : (*ksp)->ks_shortdesc);
162 		}
163 	return (0);
164 }
165 
166 /*
167  * Fills an item with predictable garbage
168  *
169  * Complies with standard dtor arg/return
170  *
171  */
172 void
173 mtrash_dtor(void *mem, int size, void *arg)
174 {
175 	int cnt;
176 	uint32_t *p;
177 
178 #ifdef DEBUG_MEMGUARD
179 	if (is_memguard_addr(mem))
180 		return;
181 #endif
182 
183 	size -= sizeof(struct malloc_type *);
184 	cnt = size / sizeof(uma_junk);
185 
186 	for (p = mem; cnt > 0; cnt--, p++)
187 		*p = uma_junk;
188 }
189 
190 /*
191  * Fills an item with predictable garbage
192  *
193  * Complies with standard init arg/return
194  *
195  */
196 int
197 mtrash_init(void *mem, int size, int flags)
198 {
199 	struct malloc_type **ksp;
200 
201 #ifdef DEBUG_MEMGUARD
202 	if (is_memguard_addr(mem))
203 		return (0);
204 #endif
205 
206 	mtrash_dtor(mem, size, NULL);
207 
208 	ksp = (struct malloc_type **)mem;
209 	ksp += (size / sizeof(struct malloc_type *)) - 1;
210 	*ksp = NULL;
211 	return (0);
212 }
213 
214 /*
215  * Checks an item to make sure it hasn't been overwritten since it was freed,
216  * prior to freeing it back to available memory.
217  *
218  * Complies with standard fini arg/return
219  *
220  */
221 void
222 mtrash_fini(void *mem, int size)
223 {
224 	(void)mtrash_ctor(mem, size, NULL, 0);
225 }
226