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 Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12 #include "config.h"
13 #include <fcntl.h>
14 #include <stdio.h>
15 #include <string.h>
16 #if HAVE_UNISTD_H
17 #include <unistd.h>
18 #endif
19 #if HAVE_ERRNO_H
20 #include <errno.h>
21 #endif
22
23 #include "ext2_fs.h"
24 #include "ext2fs.h"
25 #include "irel.h"
26
27 static errcode_t ima_put(ext2_irel irel, ext2_ino_t old,
28 struct ext2_inode_relocate_entry *ent);
29 static errcode_t ima_get(ext2_irel irel, ext2_ino_t old,
30 struct ext2_inode_relocate_entry *ent);
31 static errcode_t ima_get_by_orig(ext2_irel irel, ext2_ino_t orig, ext2_ino_t *old,
32 struct ext2_inode_relocate_entry *ent);
33 static errcode_t ima_start_iter(ext2_irel irel);
34 static errcode_t ima_next(ext2_irel irel, ext2_ino_t *old,
35 struct ext2_inode_relocate_entry *ent);
36 static errcode_t ima_add_ref(ext2_irel irel, ext2_ino_t ino,
37 struct ext2_inode_reference *ref);
38 static errcode_t ima_start_iter_ref(ext2_irel irel, ext2_ino_t ino);
39 static errcode_t ima_next_ref(ext2_irel irel, struct ext2_inode_reference *ref);
40 static errcode_t ima_move(ext2_irel irel, ext2_ino_t old, ext2_ino_t new);
41 static errcode_t ima_delete(ext2_irel irel, ext2_ino_t old);
42 static errcode_t ima_free(ext2_irel irel);
43
44 /*
45 * This data structure stores the array of inode references; there is
46 * a structure for each inode.
47 */
48 struct inode_reference_entry {
49 __u16 num;
50 struct ext2_inode_reference *refs;
51 };
52
53 struct irel_ma {
54 __u32 magic;
55 ext2_ino_t max_inode;
56 ext2_ino_t ref_current;
57 int ref_iter;
58 ext2_ino_t *orig_map;
59 struct ext2_inode_relocate_entry *entries;
60 struct inode_reference_entry *ref_entries;
61 };
62
ext2fs_irel_memarray_create(char * name,ext2_ino_t max_inode,ext2_irel * new_irel)63 errcode_t ext2fs_irel_memarray_create(char *name, ext2_ino_t max_inode,
64 ext2_irel *new_irel)
65 {
66 ext2_irel irel = 0;
67 errcode_t retval;
68 struct irel_ma *ma = 0;
69 size_t size;
70
71 *new_irel = 0;
72
73 /*
74 * Allocate memory structures
75 */
76 retval = ext2fs_get_mem(sizeof(struct ext2_inode_relocation_table),
77 &irel);
78 if (retval)
79 goto errout;
80 memset(irel, 0, sizeof(struct ext2_inode_relocation_table));
81
82 retval = ext2fs_get_mem(strlen(name)+1, &irel->name);
83 if (retval)
84 goto errout;
85 strcpy(irel->name, name);
86
87 retval = ext2fs_get_mem(sizeof(struct irel_ma), &ma);
88 if (retval)
89 goto errout;
90 memset(ma, 0, sizeof(struct irel_ma));
91 irel->priv_data = ma;
92
93 size = (size_t) (sizeof(ext2_ino_t) * (max_inode+1));
94 retval = ext2fs_get_array(max_inode+1, sizeof(ext2_ino_t),
95 &ma->orig_map);
96 if (retval)
97 goto errout;
98 memset(ma->orig_map, 0, size);
99
100 size = (size_t) (sizeof(struct ext2_inode_relocate_entry) *
101 (max_inode+1));
102 retval = ext2fs_get_array((max_inode+1,
103 sizeof(struct ext2_inode_relocate_entry), &ma->entries);
104 if (retval)
105 goto errout;
106 memset(ma->entries, 0, size);
107
108 size = (size_t) (sizeof(struct inode_reference_entry) *
109 (max_inode+1));
110 retval = ext2fs_get_mem(max_inode+1,
111 sizeof(struct inode_reference_entry), &ma->ref_entries);
112 if (retval)
113 goto errout;
114 memset(ma->ref_entries, 0, size);
115 ma->max_inode = max_inode;
116
117 /*
118 * Fill in the irel data structure
119 */
120 irel->put = ima_put;
121 irel->get = ima_get;
122 irel->get_by_orig = ima_get_by_orig;
123 irel->start_iter = ima_start_iter;
124 irel->next = ima_next;
125 irel->add_ref = ima_add_ref;
126 irel->start_iter_ref = ima_start_iter_ref;
127 irel->next_ref = ima_next_ref;
128 irel->move = ima_move;
129 irel->delete = ima_delete;
130 irel->free = ima_free;
131
132 *new_irel = irel;
133 return 0;
134
135 errout:
136 ima_free(irel);
137 return retval;
138 }
139
140 static errcode_t ima_put(ext2_irel irel, ext2_ino_t old,
141 struct ext2_inode_relocate_entry *ent)
142 {
143 struct inode_reference_entry *ref_ent;
144 struct irel_ma *ma;
145 errcode_t retval;
146 size_t size, old_size;
147
148 ma = irel->priv_data;
149 if (old > ma->max_inode)
150 return EXT2_ET_INVALID_ARGUMENT;
151
152 /*
153 * Force the orig field to the correct value; the application
154 * program shouldn't be messing with this field.
155 */
156 if (ma->entries[(unsigned) old].new == 0)
157 ent->orig = old;
158 else
159 ent->orig = ma->entries[(unsigned) old].orig;
160
161 /*
162 * If max_refs has changed, reallocate the refs array
163 */
164 ref_ent = ma->ref_entries + (unsigned) old;
165 if (ref_ent->refs && ent->max_refs !=
166 ma->entries[(unsigned) old].max_refs) {
167 size = (sizeof(struct ext2_inode_reference) * ent->max_refs);
168 old_size = (sizeof(struct ext2_inode_reference) *
169 ma->entries[(unsigned) old].max_refs);
170 retval = ext2fs_resize_mem(old_size, size, &ref_ent->refs);
171 if (retval)
172 return retval;
173 }
174
175 ma->entries[(unsigned) old] = *ent;
176 ma->orig_map[(unsigned) ent->orig] = old;
177 return 0;
178 }
179
180 static errcode_t ima_get(ext2_irel irel, ext2_ino_t old,
181 struct ext2_inode_relocate_entry *ent)
182 {
183 struct irel_ma *ma;
184
185 ma = irel->priv_data;
186 if (old > ma->max_inode)
187 return EXT2_ET_INVALID_ARGUMENT;
188 if (ma->entries[(unsigned) old].new == 0)
189 return ENOENT;
190 *ent = ma->entries[(unsigned) old];
191 return 0;
192 }
193
194 static errcode_t ima_get_by_orig(ext2_irel irel, ext2_ino_t orig, ext2_ino_t *old,
195 struct ext2_inode_relocate_entry *ent)
196 {
197 struct irel_ma *ma;
198 ext2_ino_t ino;
199
200 ma = irel->priv_data;
201 if (orig > ma->max_inode)
202 return EXT2_ET_INVALID_ARGUMENT;
203 ino = ma->orig_map[(unsigned) orig];
204 if (ino == 0)
205 return ENOENT;
206 *old = ino;
207 *ent = ma->entries[(unsigned) ino];
208 return 0;
209 }
210
211 static errcode_t ima_start_iter(ext2_irel irel)
212 {
213 irel->current = 0;
214 return 0;
215 }
216
217 static errcode_t ima_next(ext2_irel irel, ext2_ino_t *old,
218 struct ext2_inode_relocate_entry *ent)
219 {
220 struct irel_ma *ma;
221
222 ma = irel->priv_data;
223 while (++irel->current < ma->max_inode) {
224 if (ma->entries[(unsigned) irel->current].new == 0)
225 continue;
226 *old = irel->current;
227 *ent = ma->entries[(unsigned) irel->current];
228 return 0;
229 }
230 *old = 0;
231 return 0;
232 }
233
234 static errcode_t ima_add_ref(ext2_irel irel, ext2_ino_t ino,
235 struct ext2_inode_reference *ref)
236 {
237 struct irel_ma *ma;
238 size_t size;
239 struct inode_reference_entry *ref_ent;
240 struct ext2_inode_relocate_entry *ent;
241 errcode_t retval;
242
243 ma = irel->priv_data;
244 if (ino > ma->max_inode)
245 return EXT2_ET_INVALID_ARGUMENT;
246
247 ref_ent = ma->ref_entries + (unsigned) ino;
248 ent = ma->entries + (unsigned) ino;
249
250 /*
251 * If the inode reference array doesn't exist, create it.
252 */
253 if (ref_ent->refs == 0) {
254 size = (size_t) ((sizeof(struct ext2_inode_reference) *
255 ent->max_refs));
256 retval = ext2fs_get_array(ent->max_refs,
257 sizeof(struct ext2_inode_reference), &ref_ent->refs);
258 if (retval)
259 return retval;
260 memset(ref_ent->refs, 0, size);
261 ref_ent->num = 0;
262 }
263
264 if (ref_ent->num >= ent->max_refs)
265 return EXT2_ET_TOO_MANY_REFS;
266
267 ref_ent->refs[(unsigned) ref_ent->num++] = *ref;
268 return 0;
269 }
270
271 static errcode_t ima_start_iter_ref(ext2_irel irel, ext2_ino_t ino)
272 {
273 struct irel_ma *ma;
274
275 ma = irel->priv_data;
276 if (ino > ma->max_inode)
277 return EXT2_ET_INVALID_ARGUMENT;
278 if (ma->entries[(unsigned) ino].new == 0)
279 return ENOENT;
280 ma->ref_current = ino;
281 ma->ref_iter = 0;
282 return 0;
283 }
284
285 static errcode_t ima_next_ref(ext2_irel irel,
286 struct ext2_inode_reference *ref)
287 {
288 struct irel_ma *ma;
289 struct inode_reference_entry *ref_ent;
290
291 ma = irel->priv_data;
292
293 ref_ent = ma->ref_entries + ma->ref_current;
294
295 if ((ref_ent->refs == NULL) ||
296 (ma->ref_iter >= ref_ent->num)) {
297 ref->block = 0;
298 ref->offset = 0;
299 return 0;
300 }
301 *ref = ref_ent->refs[ma->ref_iter++];
302 return 0;
303 }
304
305
306 static errcode_t ima_move(ext2_irel irel, ext2_ino_t old, ext2_ino_t new)
307 {
308 struct irel_ma *ma;
309
310 ma = irel->priv_data;
311 if ((old > ma->max_inode) || (new > ma->max_inode))
312 return EXT2_ET_INVALID_ARGUMENT;
313 if (ma->entries[(unsigned) old].new == 0)
314 return ENOENT;
315
316 ma->entries[(unsigned) new] = ma->entries[(unsigned) old];
317 if (ma->ref_entries[(unsigned) new].refs)
318 ext2fs_free_mem(&ma->ref_entries[(unsigned) new].refs);
319 ma->ref_entries[(unsigned) new] = ma->ref_entries[(unsigned) old];
320
321 ma->entries[(unsigned) old].new = 0;
322 ma->ref_entries[(unsigned) old].num = 0;
323 ma->ref_entries[(unsigned) old].refs = 0;
324
325 ma->orig_map[ma->entries[new].orig] = new;
326 return 0;
327 }
328
329 static errcode_t ima_delete(ext2_irel irel, ext2_ino_t old)
330 {
331 struct irel_ma *ma;
332
333 ma = irel->priv_data;
334 if (old > ma->max_inode)
335 return EXT2_ET_INVALID_ARGUMENT;
336 if (ma->entries[(unsigned) old].new == 0)
337 return ENOENT;
338
339 ma->entries[old].new = 0;
340 if (ma->ref_entries[(unsigned) old].refs)
341 ext2fs_free_mem(&ma->ref_entries[(unsigned) old].refs);
342 ma->orig_map[ma->entries[(unsigned) old].orig] = 0;
343
344 ma->ref_entries[(unsigned) old].num = 0;
345 ma->ref_entries[(unsigned) old].refs = 0;
346 return 0;
347 }
348
349 static errcode_t ima_free(ext2_irel irel)
350 {
351 struct irel_ma *ma;
352 ext2_ino_t ino;
353
354 if (!irel)
355 return 0;
356
357 ma = irel->priv_data;
358
359 if (ma) {
360 if (ma->orig_map)
361 ext2fs_free_mem(&ma->orig_map);
362 if (ma->entries)
363 ext2fs_free_mem(&ma->entries);
364 if (ma->ref_entries) {
365 for (ino = 0; ino <= ma->max_inode; ino++) {
366 if (ma->ref_entries[(unsigned) ino].refs)
367 ext2fs_free_mem(&ma->ref_entries[(unsigned) ino].refs);
368 }
369 ext2fs_free_mem(&ma->ref_entries);
370 }
371 ext2fs_free_mem(&ma);
372 }
373 if (irel->name)
374 ext2fs_free_mem(&irel->name);
375 ext2fs_free_mem(&irel);
376 return 0;
377 }
378