1 /* 2 * Copyright (c) 2002, Jeffrey Roberson <jroberson@chesapeake.net> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 * 28 */ 29 30 /* 31 * uma_dbg.c Debugging features for UMA users 32 * 33 */ 34 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/types.h> 40 #include <sys/queue.h> 41 #include <sys/lock.h> 42 #include <sys/mutex.h> 43 #include <sys/malloc.h> 44 45 #include <vm/uma.h> 46 #include <vm/uma_int.h> 47 #include <vm/uma_dbg.h> 48 49 static const u_int32_t uma_junk = 0xdeadc0de; 50 51 /* 52 * Checks an item to make sure it hasn't been overwritten since freed. 53 * 54 * Complies with standard ctor arg/return 55 * 56 */ 57 void 58 trash_ctor(void *mem, int size, void *arg) 59 { 60 int cnt; 61 u_int32_t *p; 62 63 cnt = size / sizeof(uma_junk); 64 65 for (p = mem; cnt > 0; cnt--, p++) 66 if (*p != uma_junk) 67 panic("Memory modified after free %p(%d)\n", 68 mem, size); 69 } 70 71 /* 72 * Fills an item with predictable garbage 73 * 74 * Complies with standard dtor arg/return 75 * 76 */ 77 void 78 trash_dtor(void *mem, int size, void *arg) 79 { 80 int cnt; 81 u_int32_t *p; 82 83 cnt = size / sizeof(uma_junk); 84 85 for (p = mem; cnt > 0; cnt--, p++) 86 *p = uma_junk; 87 } 88 89 /* 90 * Fills an item with predictable garbage 91 * 92 * Complies with standard init arg/return 93 * 94 */ 95 void 96 trash_init(void *mem, int size) 97 { 98 trash_dtor(mem, size, NULL); 99 } 100 101 /* 102 * Checks an item to make sure it hasn't been overwritten since it was freed. 103 * 104 * Complies with standard fini arg/return 105 * 106 */ 107 void 108 trash_fini(void *mem, int size) 109 { 110 trash_ctor(mem, size, NULL); 111 } 112 113 /* 114 * Checks an item to make sure it hasn't been overwritten since freed. 115 * 116 * Complies with standard ctor arg/return 117 * 118 */ 119 void 120 mtrash_ctor(void *mem, int size, void *arg) 121 { 122 struct malloc_type **ksp; 123 u_int32_t *p = mem; 124 int cnt; 125 126 size -= sizeof(struct malloc_type *); 127 ksp = (struct malloc_type **)mem; 128 ksp += size / sizeof(struct malloc_type *); 129 cnt = size / sizeof(uma_junk); 130 131 for (p = mem; cnt > 0; cnt--, p++) 132 if (*p != uma_junk) { 133 printf("Memory modified after free %p(%d)\n", 134 mem, size); 135 panic("Most recently used by %s\n", (*ksp == NULL)? 136 "none" : (*ksp)->ks_shortdesc); 137 } 138 } 139 140 /* 141 * Fills an item with predictable garbage 142 * 143 * Complies with standard dtor arg/return 144 * 145 */ 146 void 147 mtrash_dtor(void *mem, int size, void *arg) 148 { 149 int cnt; 150 u_int32_t *p; 151 152 size -= sizeof(struct malloc_type *); 153 cnt = size / sizeof(uma_junk); 154 155 for (p = mem; cnt > 0; cnt--, p++) 156 *p = uma_junk; 157 } 158 159 /* 160 * Fills an item with predictable garbage 161 * 162 * Complies with standard init arg/return 163 * 164 */ 165 void 166 mtrash_init(void *mem, int size) 167 { 168 struct malloc_type **ksp; 169 170 mtrash_dtor(mem, size, NULL); 171 172 ksp = (struct malloc_type **)mem; 173 ksp += (size / sizeof(struct malloc_type *)) - 1; 174 *ksp = NULL; 175 } 176 177 /* 178 * Checks an item to make sure it hasn't been overwritten since it was freed. 179 * 180 * Complies with standard fini arg/return 181 * 182 */ 183 void 184 mtrash_fini(void *mem, int size) 185 { 186 mtrash_ctor(mem, size, NULL); 187 } 188 189 static uma_slab_t 190 uma_dbg_getslab(uma_zone_t zone, void *item) 191 { 192 uma_slab_t slab; 193 u_int8_t *mem; 194 195 mem = (u_int8_t *)((unsigned long)item & (~UMA_SLAB_MASK)); 196 if (zone->uz_flags & UMA_ZFLAG_MALLOC) { 197 mtx_lock(&malloc_mtx); 198 slab = hash_sfind(mallochash, mem); 199 mtx_unlock(&malloc_mtx); 200 } else if (zone->uz_flags & UMA_ZFLAG_OFFPAGE) { 201 ZONE_LOCK(zone); 202 slab = hash_sfind(&zone->uz_hash, mem); 203 ZONE_UNLOCK(zone); 204 } else { 205 mem += zone->uz_pgoff; 206 slab = (uma_slab_t)mem; 207 } 208 209 return (slab); 210 } 211 212 /* 213 * Set up the slab's freei data such that uma_dbg_free can function. 214 * 215 */ 216 217 void 218 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item) 219 { 220 int freei; 221 222 if (slab == NULL) { 223 slab = uma_dbg_getslab(zone, item); 224 if (slab == NULL) 225 panic("uma: item %p did not belong to zone %s\n", 226 item, zone->uz_name); 227 } 228 229 freei = ((unsigned long)item - (unsigned long)slab->us_data) 230 / zone->uz_rsize; 231 232 slab->us_freelist[freei] = 255; 233 234 return; 235 } 236 237 /* 238 * Verifies freed addresses. Checks for alignment, valid slab membership 239 * and duplicate frees. 240 * 241 */ 242 243 void 244 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item) 245 { 246 int freei; 247 248 if (slab == NULL) { 249 slab = uma_dbg_getslab(zone, item); 250 if (slab == NULL) 251 panic("uma: Freed item %p did not belong to zone %s\n", 252 item, zone->uz_name); 253 } 254 255 freei = ((unsigned long)item - (unsigned long)slab->us_data) 256 / zone->uz_rsize; 257 258 if (freei >= zone->uz_ipers) 259 panic("zone: %s(%p) slab %p freelist %d out of range 0-%d\n", 260 zone->uz_name, zone, slab, freei, zone->uz_ipers-1); 261 262 if (((freei * zone->uz_rsize) + slab->us_data) != item) { 263 printf("zone: %s(%p) slab %p freed address %p unaligned.\n", 264 zone->uz_name, zone, slab, item); 265 panic("should be %p\n", 266 (freei * zone->uz_rsize) + slab->us_data); 267 } 268 269 if (slab->us_freelist[freei] != 255) { 270 printf("Slab at %p, freei %d = %d.\n", 271 slab, freei, slab->us_freelist[freei]); 272 panic("Duplicate free of item %p from zone %p(%s)\n", 273 item, zone, zone->uz_name); 274 } 275 276 /* 277 * When this is actually linked into the slab this will change. 278 * Until then the count of valid slabs will make sure we don't 279 * accidentally follow this and assume it's a valid index. 280 */ 281 slab->us_freelist[freei] = 0; 282 } 283