irel_ma.c revision 31dbecd482405e0d3a67eb58e1a1c8cb9f2ad83e
1/* 2 * irel_ma.c 3 * 4 * Copyright (C) 1996, 1997 Theodore Ts'o. 5 * 6 * %Begin-Header% 7 * This file may be redistributed under the terms of the GNU Public 8 * License. 9 * %End-Header% 10 */ 11 12#include <fcntl.h> 13#include <stdio.h> 14#include <string.h> 15#if HAVE_UNISTD_H 16#include <unistd.h> 17#endif 18#if HAVE_ERRNO_H 19#include <errno.h> 20#endif 21 22#if EXT2_FLAT_INCLUDES 23#include "ext2_fs.h" 24#else 25#include <linux/ext2_fs.h> 26#endif 27 28#include "ext2fs.h" 29#include "irel.h" 30 31static errcode_t ima_put(ext2_irel irel, ext2_ino_t old, 32 struct ext2_inode_relocate_entry *ent); 33static errcode_t ima_get(ext2_irel irel, ext2_ino_t old, 34 struct ext2_inode_relocate_entry *ent); 35static errcode_t ima_get_by_orig(ext2_irel irel, ext2_ino_t orig, ext2_ino_t *old, 36 struct ext2_inode_relocate_entry *ent); 37static errcode_t ima_start_iter(ext2_irel irel); 38static errcode_t ima_next(ext2_irel irel, ext2_ino_t *old, 39 struct ext2_inode_relocate_entry *ent); 40static errcode_t ima_add_ref(ext2_irel irel, ext2_ino_t ino, 41 struct ext2_inode_reference *ref); 42static errcode_t ima_start_iter_ref(ext2_irel irel, ext2_ino_t ino); 43static errcode_t ima_next_ref(ext2_irel irel, struct ext2_inode_reference *ref); 44static errcode_t ima_move(ext2_irel irel, ext2_ino_t old, ext2_ino_t new); 45static errcode_t ima_delete(ext2_irel irel, ext2_ino_t old); 46static errcode_t ima_free(ext2_irel irel); 47 48/* 49 * This data structure stores the array of inode references; there is 50 * a structure for each inode. 51 */ 52struct inode_reference_entry { 53 __u16 num; 54 struct ext2_inode_reference *refs; 55}; 56 57struct irel_ma { 58 __u32 magic; 59 ext2_ino_t max_inode; 60 ext2_ino_t ref_current; 61 int ref_iter; 62 ext2_ino_t *orig_map; 63 struct ext2_inode_relocate_entry *entries; 64 struct inode_reference_entry *ref_entries; 65}; 66 67errcode_t ext2fs_irel_memarray_create(char *name, ext2_ino_t max_inode, 68 ext2_irel *new_irel) 69{ 70 ext2_irel irel = 0; 71 errcode_t retval; 72 struct irel_ma *ma = 0; 73 size_t size; 74 75 *new_irel = 0; 76 77 /* 78 * Allocate memory structures 79 */ 80 retval = ext2fs_get_mem(sizeof(struct ext2_inode_relocation_table), 81 (void **) &irel); 82 if (retval) 83 goto errout; 84 memset(irel, 0, sizeof(struct ext2_inode_relocation_table)); 85 86 retval = ext2fs_get_mem(strlen(name)+1, (void **) &irel->name); 87 if (retval) 88 goto errout; 89 strcpy(irel->name, name); 90 91 retval = ext2fs_get_mem(sizeof(struct irel_ma), (void **) &ma); 92 if (retval) 93 goto errout; 94 memset(ma, 0, sizeof(struct irel_ma)); 95 irel->priv_data = ma; 96 97 size = (size_t) (sizeof(ext2_ino_t) * (max_inode+1)); 98 retval = ext2fs_get_mem(size, (void **) &ma->orig_map); 99 if (retval) 100 goto errout; 101 memset(ma->orig_map, 0, size); 102 103 size = (size_t) (sizeof(struct ext2_inode_relocate_entry) * 104 (max_inode+1)); 105 retval = ext2fs_get_mem(size, (void **) &ma->entries); 106 if (retval) 107 goto errout; 108 memset(ma->entries, 0, size); 109 110 size = (size_t) (sizeof(struct inode_reference_entry) * 111 (max_inode+1)); 112 retval = ext2fs_get_mem(size, (void **) &ma->ref_entries); 113 if (retval) 114 goto errout; 115 memset(ma->ref_entries, 0, size); 116 ma->max_inode = max_inode; 117 118 /* 119 * Fill in the irel data structure 120 */ 121 irel->put = ima_put; 122 irel->get = ima_get; 123 irel->get_by_orig = ima_get_by_orig; 124 irel->start_iter = ima_start_iter; 125 irel->next = ima_next; 126 irel->add_ref = ima_add_ref; 127 irel->start_iter_ref = ima_start_iter_ref; 128 irel->next_ref = ima_next_ref; 129 irel->move = ima_move; 130 irel->delete = ima_delete; 131 irel->free = ima_free; 132 133 *new_irel = irel; 134 return 0; 135 136errout: 137 ima_free(irel); 138 return retval; 139} 140 141static errcode_t ima_put(ext2_irel irel, ext2_ino_t old, 142 struct ext2_inode_relocate_entry *ent) 143{ 144 struct inode_reference_entry *ref_ent; 145 struct irel_ma *ma; 146 errcode_t retval; 147 size_t size, old_size; 148 149 ma = irel->priv_data; 150 if (old > ma->max_inode) 151 return EXT2_ET_INVALID_ARGUMENT; 152 153 /* 154 * Force the orig field to the correct value; the application 155 * program shouldn't be messing with this field. 156 */ 157 if (ma->entries[(unsigned) old].new == 0) 158 ent->orig = old; 159 else 160 ent->orig = ma->entries[(unsigned) old].orig; 161 162 /* 163 * If max_refs has changed, reallocate the refs array 164 */ 165 ref_ent = ma->ref_entries + (unsigned) old; 166 if (ref_ent->refs && ent->max_refs != 167 ma->entries[(unsigned) old].max_refs) { 168 size = (sizeof(struct ext2_inode_reference) * ent->max_refs); 169 old_size = (sizeof(struct ext2_inode_reference) * 170 ma->entries[(unsigned) old].max_refs); 171 retval = ext2fs_resize_mem(old_size, size, 172 (void **) &ref_ent->refs); 173 if (retval) 174 return retval; 175 } 176 177 ma->entries[(unsigned) old] = *ent; 178 ma->orig_map[(unsigned) ent->orig] = old; 179 return 0; 180} 181 182static errcode_t ima_get(ext2_irel irel, ext2_ino_t old, 183 struct ext2_inode_relocate_entry *ent) 184{ 185 struct irel_ma *ma; 186 187 ma = irel->priv_data; 188 if (old > ma->max_inode) 189 return EXT2_ET_INVALID_ARGUMENT; 190 if (ma->entries[(unsigned) old].new == 0) 191 return ENOENT; 192 *ent = ma->entries[(unsigned) old]; 193 return 0; 194} 195 196static errcode_t ima_get_by_orig(ext2_irel irel, ext2_ino_t orig, ext2_ino_t *old, 197 struct ext2_inode_relocate_entry *ent) 198{ 199 struct irel_ma *ma; 200 ext2_ino_t ino; 201 202 ma = irel->priv_data; 203 if (orig > ma->max_inode) 204 return EXT2_ET_INVALID_ARGUMENT; 205 ino = ma->orig_map[(unsigned) orig]; 206 if (ino == 0) 207 return ENOENT; 208 *old = ino; 209 *ent = ma->entries[(unsigned) ino]; 210 return 0; 211} 212 213static errcode_t ima_start_iter(ext2_irel irel) 214{ 215 irel->current = 0; 216 return 0; 217} 218 219static errcode_t ima_next(ext2_irel irel, ext2_ino_t *old, 220 struct ext2_inode_relocate_entry *ent) 221{ 222 struct irel_ma *ma; 223 224 ma = irel->priv_data; 225 while (++irel->current < ma->max_inode) { 226 if (ma->entries[(unsigned) irel->current].new == 0) 227 continue; 228 *old = irel->current; 229 *ent = ma->entries[(unsigned) irel->current]; 230 return 0; 231 } 232 *old = 0; 233 return 0; 234} 235 236static errcode_t ima_add_ref(ext2_irel irel, ext2_ino_t ino, 237 struct ext2_inode_reference *ref) 238{ 239 struct irel_ma *ma; 240 size_t size; 241 struct inode_reference_entry *ref_ent; 242 struct ext2_inode_relocate_entry *ent; 243 errcode_t retval; 244 245 ma = irel->priv_data; 246 if (ino > ma->max_inode) 247 return EXT2_ET_INVALID_ARGUMENT; 248 249 ref_ent = ma->ref_entries + (unsigned) ino; 250 ent = ma->entries + (unsigned) ino; 251 252 /* 253 * If the inode reference array doesn't exist, create it. 254 */ 255 if (ref_ent->refs == 0) { 256 size = (size_t) ((sizeof(struct ext2_inode_reference) * 257 ent->max_refs)); 258 retval = ext2fs_get_mem(size, (void **) &ref_ent->refs); 259 if (retval) 260 return retval; 261 memset(ref_ent->refs, 0, size); 262 ref_ent->num = 0; 263 } 264 265 if (ref_ent->num >= ent->max_refs) 266 return EXT2_ET_TOO_MANY_REFS; 267 268 ref_ent->refs[(unsigned) ref_ent->num++] = *ref; 269 return 0; 270} 271 272static errcode_t ima_start_iter_ref(ext2_irel irel, ext2_ino_t ino) 273{ 274 struct irel_ma *ma; 275 276 ma = irel->priv_data; 277 if (ino > ma->max_inode) 278 return EXT2_ET_INVALID_ARGUMENT; 279 if (ma->entries[(unsigned) ino].new == 0) 280 return ENOENT; 281 ma->ref_current = ino; 282 ma->ref_iter = 0; 283 return 0; 284} 285 286static errcode_t ima_next_ref(ext2_irel irel, 287 struct ext2_inode_reference *ref) 288{ 289 struct irel_ma *ma; 290 struct inode_reference_entry *ref_ent; 291 292 ma = irel->priv_data; 293 294 ref_ent = ma->ref_entries + ma->ref_current; 295 296 if ((ref_ent->refs == NULL) || 297 (ma->ref_iter >= ref_ent->num)) { 298 ref->block = 0; 299 ref->offset = 0; 300 return 0; 301 } 302 *ref = ref_ent->refs[ma->ref_iter++]; 303 return 0; 304} 305 306 307static errcode_t ima_move(ext2_irel irel, ext2_ino_t old, ext2_ino_t new) 308{ 309 struct irel_ma *ma; 310 311 ma = irel->priv_data; 312 if ((old > ma->max_inode) || (new > ma->max_inode)) 313 return EXT2_ET_INVALID_ARGUMENT; 314 if (ma->entries[(unsigned) old].new == 0) 315 return ENOENT; 316 317 ma->entries[(unsigned) new] = ma->entries[(unsigned) old]; 318 if (ma->ref_entries[(unsigned) new].refs) 319 ext2fs_free_mem((void **) &ma->ref_entries[(unsigned) new].refs); 320 ma->ref_entries[(unsigned) new] = ma->ref_entries[(unsigned) old]; 321 322 ma->entries[(unsigned) old].new = 0; 323 ma->ref_entries[(unsigned) old].num = 0; 324 ma->ref_entries[(unsigned) old].refs = 0; 325 326 ma->orig_map[ma->entries[new].orig] = new; 327 return 0; 328} 329 330static errcode_t ima_delete(ext2_irel irel, ext2_ino_t old) 331{ 332 struct irel_ma *ma; 333 334 ma = irel->priv_data; 335 if (old > ma->max_inode) 336 return EXT2_ET_INVALID_ARGUMENT; 337 if (ma->entries[(unsigned) old].new == 0) 338 return ENOENT; 339 340 ma->entries[old].new = 0; 341 if (ma->ref_entries[(unsigned) old].refs) 342 ext2fs_free_mem((void **) &ma->ref_entries[(unsigned) old].refs); 343 ma->orig_map[ma->entries[(unsigned) old].orig] = 0; 344 345 ma->ref_entries[(unsigned) old].num = 0; 346 ma->ref_entries[(unsigned) old].refs = 0; 347 return 0; 348} 349 350static errcode_t ima_free(ext2_irel irel) 351{ 352 struct irel_ma *ma; 353 ext2_ino_t ino; 354 355 if (!irel) 356 return 0; 357 358 ma = irel->priv_data; 359 360 if (ma) { 361 if (ma->orig_map) 362 ext2fs_free_mem((void **) &ma->orig_map); 363 if (ma->entries) 364 ext2fs_free_mem((void **) &ma->entries); 365 if (ma->ref_entries) { 366 for (ino = 0; ino <= ma->max_inode; ino++) { 367 if (ma->ref_entries[(unsigned) ino].refs) 368 ext2fs_free_mem((void **) &ma->ref_entries[(unsigned) ino].refs); 369 } 370 ext2fs_free_mem((void **) &ma->ref_entries); 371 } 372 ext2fs_free_mem((void **) &ma); 373 } 374 if (irel->name) 375 ext2fs_free_mem((void **) &irel->name); 376 ext2fs_free_mem((void **) &irel); 377 return 0; 378} 379