1 /*
2 * dirinfo.c --- maintains the directory information table for e2fsck.
3 *
4 * Copyright (C) 1993 Theodore Ts'o. This file may be redistributed
5 * under the terms of the GNU Public License.
6 */
7
8 #undef DIRINFO_DEBUG
9
10 #include "config.h"
11 #include "e2fsck.h"
12 #include <sys/stat.h>
13 #include <fcntl.h>
14 #include "uuid/uuid.h"
15
16 #include "ext2fs/ext2fs.h"
17 #include <ext2fs/tdb.h>
18
19 struct dir_info_db {
20 ext2_ino_t count;
21 ext2_ino_t size;
22 struct dir_info *array;
23 struct dir_info *last_lookup;
24 #ifdef CONFIG_TDB
25 char *tdb_fn;
26 TDB_CONTEXT *tdb;
27 #endif
28 };
29
30 struct dir_info_iter {
31 ext2_ino_t i;
32 #ifdef CONFIG_TDB
33 TDB_DATA tdb_iter;
34 #endif
35 };
36
37 struct dir_info_ent {
38 ext2_ino_t dotdot; /* Parent according to '..' */
39 ext2_ino_t parent; /* Parent according to treewalk */
40 };
41
42
43 static void e2fsck_put_dir_info(e2fsck_t ctx, struct dir_info *dir);
44
45 #ifdef CONFIG_TDB
setup_tdb(e2fsck_t ctx,ext2_ino_t num_dirs)46 static void setup_tdb(e2fsck_t ctx, ext2_ino_t num_dirs)
47 {
48 struct dir_info_db *db = ctx->dir_info;
49 ext2_ino_t threshold;
50 errcode_t retval;
51 mode_t save_umask;
52 char *tdb_dir, uuid[40];
53 int fd, enable;
54
55 profile_get_string(ctx->profile, "scratch_files", "directory", 0, 0,
56 &tdb_dir);
57 profile_get_uint(ctx->profile, "scratch_files",
58 "numdirs_threshold", 0, 0, &threshold);
59 profile_get_boolean(ctx->profile, "scratch_files",
60 "dirinfo", 0, 1, &enable);
61
62 if (!enable || !tdb_dir || access(tdb_dir, W_OK) ||
63 (threshold && num_dirs <= threshold))
64 return;
65
66 retval = ext2fs_get_mem(strlen(tdb_dir) + 64, &db->tdb_fn);
67 if (retval)
68 return;
69
70 uuid_unparse(ctx->fs->super->s_uuid, uuid);
71 sprintf(db->tdb_fn, "%s/%s-dirinfo-XXXXXX", tdb_dir, uuid);
72 save_umask = umask(077);
73 fd = mkstemp(db->tdb_fn);
74 umask(save_umask);
75 if (fd < 0) {
76 db->tdb = NULL;
77 return;
78 }
79
80 if (num_dirs < 99991)
81 num_dirs = 99991; /* largest 5 digit prime */
82
83 db->tdb = tdb_open(db->tdb_fn, num_dirs, TDB_NOLOCK | TDB_NOSYNC,
84 O_RDWR | O_CREAT | O_TRUNC, 0600);
85 close(fd);
86 }
87 #endif
88
setup_db(e2fsck_t ctx)89 static void setup_db(e2fsck_t ctx)
90 {
91 struct dir_info_db *db;
92 ext2_ino_t num_dirs;
93 errcode_t retval;
94
95 db = (struct dir_info_db *)
96 e2fsck_allocate_memory(ctx, sizeof(struct dir_info_db),
97 "directory map db");
98 db->count = db->size = 0;
99 db->array = 0;
100
101 ctx->dir_info = db;
102
103 retval = ext2fs_get_num_dirs(ctx->fs, &num_dirs);
104 if (retval)
105 num_dirs = 1024; /* Guess */
106
107 #ifdef CONFIG_TDB
108 setup_tdb(ctx, num_dirs);
109
110 if (db->tdb) {
111 #ifdef DIRINFO_DEBUG
112 printf("Note: using tdb!\n");
113 #endif
114 return;
115 }
116 #endif
117
118 db->size = num_dirs + 10;
119 db->array = (struct dir_info *)
120 e2fsck_allocate_memory(ctx, db->size
121 * sizeof (struct dir_info),
122 "directory map");
123 }
124
125 /*
126 * This subroutine is called during pass1 to create a directory info
127 * entry. During pass1, the passed-in parent is 0; it will get filled
128 * in during pass2.
129 */
e2fsck_add_dir_info(e2fsck_t ctx,ext2_ino_t ino,ext2_ino_t parent)130 void e2fsck_add_dir_info(e2fsck_t ctx, ext2_ino_t ino, ext2_ino_t parent)
131 {
132 struct dir_info *dir, *old_array;
133 ext2_ino_t i, j;
134 errcode_t retval;
135 unsigned long old_size;
136
137 #ifdef DIRINFO_DEBUG
138 printf("add_dir_info for inode (%u, %u)...\n", ino, parent);
139 #endif
140 if (!ctx->dir_info)
141 setup_db(ctx);
142
143 if (ctx->dir_info->count >= ctx->dir_info->size) {
144 old_size = ctx->dir_info->size * sizeof(struct dir_info);
145 ctx->dir_info->size += 10;
146 old_array = ctx->dir_info->array;
147 retval = ext2fs_resize_mem(old_size, ctx->dir_info->size *
148 sizeof(struct dir_info),
149 &ctx->dir_info->array);
150 if (retval) {
151 fprintf(stderr, "Couldn't reallocate dir_info "
152 "structure to %u entries\n",
153 ctx->dir_info->size);
154 fatal_error(ctx, 0);
155 ctx->dir_info->size -= 10;
156 return;
157 }
158 if (old_array != ctx->dir_info->array)
159 ctx->dir_info->last_lookup = NULL;
160 }
161
162 #ifdef CONFIG_TDB
163 if (ctx->dir_info->tdb) {
164 struct dir_info ent;
165
166 ent.ino = ino;
167 ent.parent = parent;
168 ent.dotdot = parent;
169 e2fsck_put_dir_info(ctx, &ent);
170 return;
171 }
172 #endif
173
174 /*
175 * Normally, add_dir_info is called with each inode in
176 * sequential order; but once in a while (like when pass 3
177 * needs to recreate the root directory or lost+found
178 * directory) it is called out of order. In those cases, we
179 * need to move the dir_info entries down to make room, since
180 * the dir_info array needs to be sorted by inode number for
181 * get_dir_info()'s sake.
182 */
183 if (ctx->dir_info->count &&
184 ctx->dir_info->array[ctx->dir_info->count-1].ino >= ino) {
185 for (i = ctx->dir_info->count-1; i > 0; i--)
186 if (ctx->dir_info->array[i-1].ino < ino)
187 break;
188 dir = &ctx->dir_info->array[i];
189 if (dir->ino != ino)
190 for (j = ctx->dir_info->count++; j > i; j--)
191 ctx->dir_info->array[j] = ctx->dir_info->array[j-1];
192 } else
193 dir = &ctx->dir_info->array[ctx->dir_info->count++];
194
195 dir->ino = ino;
196 dir->dotdot = parent;
197 dir->parent = parent;
198 }
199
200 /*
201 * get_dir_info() --- given an inode number, try to find the directory
202 * information entry for it.
203 */
e2fsck_get_dir_info(e2fsck_t ctx,ext2_ino_t ino)204 static struct dir_info *e2fsck_get_dir_info(e2fsck_t ctx, ext2_ino_t ino)
205 {
206 struct dir_info_db *db = ctx->dir_info;
207 ext2_ino_t low, high, mid;
208
209 if (!db)
210 return 0;
211
212 #ifdef DIRINFO_DEBUG
213 printf("e2fsck_get_dir_info %u...", ino);
214 #endif
215
216 #ifdef CONFIG_TDB
217 if (db->tdb) {
218 static struct dir_info ret_dir_info;
219 TDB_DATA key, data;
220 struct dir_info_ent *buf;
221
222 key.dptr = (unsigned char *) &ino;
223 key.dsize = sizeof(ext2_ino_t);
224
225 data = tdb_fetch(db->tdb, key);
226 if (!data.dptr) {
227 if (tdb_error(db->tdb) != TDB_ERR_NOEXIST)
228 printf("fetch failed: %s\n",
229 tdb_errorstr(db->tdb));
230 return 0;
231 }
232
233 buf = (struct dir_info_ent *) data.dptr;
234 ret_dir_info.ino = ino;
235 ret_dir_info.dotdot = buf->dotdot;
236 ret_dir_info.parent = buf->parent;
237 #ifdef DIRINFO_DEBUG
238 printf("(%u,%u,%u)\n", ino, buf->dotdot, buf->parent);
239 #endif
240 free(data.dptr);
241 return &ret_dir_info;
242 }
243 #endif
244
245 if (db->last_lookup && db->last_lookup->ino == ino)
246 return db->last_lookup;
247
248 low = 0;
249 high = ctx->dir_info->count - 1;
250 if (ino == ctx->dir_info->array[low].ino) {
251 #ifdef DIRINFO_DEBUG
252 printf("(%u,%u,%u)\n", ino,
253 ctx->dir_info->array[low].dotdot,
254 ctx->dir_info->array[low].parent);
255 #endif
256 return &ctx->dir_info->array[low];
257 }
258 if (ino == ctx->dir_info->array[high].ino) {
259 #ifdef DIRINFO_DEBUG
260 printf("(%u,%u,%u)\n", ino,
261 ctx->dir_info->array[high].dotdot,
262 ctx->dir_info->array[high].parent);
263 #endif
264 return &ctx->dir_info->array[high];
265 }
266
267 while (low < high) {
268 /* sum may overflow, but result will fit into mid again */
269 mid = (unsigned long long)(low + high) / 2;
270 if (mid == low || mid == high)
271 break;
272 if (ino == ctx->dir_info->array[mid].ino) {
273 #ifdef DIRINFO_DEBUG
274 printf("(%u,%u,%u)\n", ino,
275 ctx->dir_info->array[mid].dotdot,
276 ctx->dir_info->array[mid].parent);
277 #endif
278 return &ctx->dir_info->array[mid];
279 }
280 if (ino < ctx->dir_info->array[mid].ino)
281 high = mid;
282 else
283 low = mid;
284 }
285 return 0;
286 }
287
e2fsck_put_dir_info(e2fsck_t ctx EXT2FS_NO_TDB_UNUSED,struct dir_info * dir EXT2FS_NO_TDB_UNUSED)288 static void e2fsck_put_dir_info(e2fsck_t ctx EXT2FS_NO_TDB_UNUSED,
289 struct dir_info *dir EXT2FS_NO_TDB_UNUSED)
290 {
291 #ifdef CONFIG_TDB
292 struct dir_info_db *db = ctx->dir_info;
293 struct dir_info_ent buf;
294 TDB_DATA key, data;
295 #endif
296
297 #ifdef DIRINFO_DEBUG
298 printf("e2fsck_put_dir_info (%u, %u, %u)...", dir->ino, dir->dotdot,
299 dir->parent);
300 #endif
301
302 #ifdef CONFIG_TDB
303 if (!db->tdb)
304 return;
305
306 buf.parent = dir->parent;
307 buf.dotdot = dir->dotdot;
308
309 key.dptr = (unsigned char *) &dir->ino;
310 key.dsize = sizeof(ext2_ino_t);
311 data.dptr = (unsigned char *) &buf;
312 data.dsize = sizeof(buf);
313
314 if (tdb_store(db->tdb, key, data, TDB_REPLACE) == -1) {
315 printf("store failed: %s\n", tdb_errorstr(db->tdb));
316 }
317 #endif
318 }
319
320 /*
321 * Free the dir_info structure when it isn't needed any more.
322 */
e2fsck_free_dir_info(e2fsck_t ctx)323 void e2fsck_free_dir_info(e2fsck_t ctx)
324 {
325 if (ctx->dir_info) {
326 #ifdef CONFIG_TDB
327 if (ctx->dir_info->tdb)
328 tdb_close(ctx->dir_info->tdb);
329 if (ctx->dir_info->tdb_fn) {
330 if (unlink(ctx->dir_info->tdb_fn) < 0)
331 com_err("e2fsck_free_dir_info", errno,
332 _("while freeing dir_info tdb file"));
333 ext2fs_free_mem(&ctx->dir_info->tdb_fn);
334 }
335 #endif
336 if (ctx->dir_info->array)
337 ext2fs_free_mem(&ctx->dir_info->array);
338 ctx->dir_info->array = 0;
339 ctx->dir_info->size = 0;
340 ctx->dir_info->count = 0;
341 ext2fs_free_mem(&ctx->dir_info);
342 ctx->dir_info = 0;
343 }
344 }
345
346 /*
347 * Return the count of number of directories in the dir_info structure
348 */
e2fsck_get_num_dirinfo(e2fsck_t ctx)349 int e2fsck_get_num_dirinfo(e2fsck_t ctx)
350 {
351 return ctx->dir_info ? ctx->dir_info->count : 0;
352 }
353
e2fsck_dir_info_iter_begin(e2fsck_t ctx)354 struct dir_info_iter *e2fsck_dir_info_iter_begin(e2fsck_t ctx)
355 {
356 struct dir_info_iter *iter;
357
358 iter = e2fsck_allocate_memory(ctx, sizeof(struct dir_info_iter),
359 "dir_info iterator");
360
361 #ifdef CONFIG_TDB
362 if (ctx->dir_info->tdb)
363 iter->tdb_iter = tdb_firstkey(ctx->dir_info->tdb);
364 #endif
365
366 return iter;
367 }
368
e2fsck_dir_info_iter_end(e2fsck_t ctx EXT2FS_ATTR ((unused)),struct dir_info_iter * iter)369 void e2fsck_dir_info_iter_end(e2fsck_t ctx EXT2FS_ATTR((unused)),
370 struct dir_info_iter *iter)
371 {
372 #ifdef CONFIG_TDB
373 free(iter->tdb_iter.dptr);
374 #endif
375 ext2fs_free_mem(&iter);
376 }
377
378 /*
379 * A simple iterator function
380 */
e2fsck_dir_info_iter(e2fsck_t ctx,struct dir_info_iter * iter)381 struct dir_info *e2fsck_dir_info_iter(e2fsck_t ctx, struct dir_info_iter *iter)
382 {
383 if (!ctx->dir_info || !iter)
384 return 0;
385
386 #ifdef CONFIG_TDB
387 if (ctx->dir_info->tdb) {
388 static struct dir_info ret_dir_info;
389 struct dir_info_ent *buf;
390 TDB_DATA data, key;
391
392 if (iter->tdb_iter.dptr == 0)
393 return 0;
394 key = iter->tdb_iter;
395 data = tdb_fetch(ctx->dir_info->tdb, key);
396 if (!data.dptr) {
397 printf("iter fetch failed: %s\n",
398 tdb_errorstr(ctx->dir_info->tdb));
399 return 0;
400 }
401 buf = (struct dir_info_ent *) data.dptr;
402 ret_dir_info.ino = *((ext2_ino_t *) iter->tdb_iter.dptr);
403 ret_dir_info.dotdot = buf->dotdot;
404 ret_dir_info.parent = buf->parent;
405 iter->tdb_iter = tdb_nextkey(ctx->dir_info->tdb, key);
406 free(key.dptr);
407 free(data.dptr);
408 return &ret_dir_info;
409 }
410 #endif
411
412 if (iter->i >= ctx->dir_info->count)
413 return 0;
414
415 #ifdef DIRINFO_DEBUG
416 printf("iter(%u, %u, %u)...", ctx->dir_info->array[iter->i].ino,
417 ctx->dir_info->array[iter->i].dotdot,
418 ctx->dir_info->array[iter->i].parent);
419 #endif
420 ctx->dir_info->last_lookup = ctx->dir_info->array + iter->i++;
421 return(ctx->dir_info->last_lookup);
422 }
423
424 /*
425 * This function only sets the parent pointer, and requires that
426 * dirinfo structure has already been created.
427 */
e2fsck_dir_info_set_parent(e2fsck_t ctx,ext2_ino_t ino,ext2_ino_t parent)428 int e2fsck_dir_info_set_parent(e2fsck_t ctx, ext2_ino_t ino,
429 ext2_ino_t parent)
430 {
431 struct dir_info *p;
432
433 p = e2fsck_get_dir_info(ctx, ino);
434 if (!p)
435 return 1;
436 p->parent = parent;
437 e2fsck_put_dir_info(ctx, p);
438 return 0;
439 }
440
441 /*
442 * This function only sets the dot dot pointer, and requires that
443 * dirinfo structure has already been created.
444 */
e2fsck_dir_info_set_dotdot(e2fsck_t ctx,ext2_ino_t ino,ext2_ino_t dotdot)445 int e2fsck_dir_info_set_dotdot(e2fsck_t ctx, ext2_ino_t ino,
446 ext2_ino_t dotdot)
447 {
448 struct dir_info *p;
449
450 p = e2fsck_get_dir_info(ctx, ino);
451 if (!p)
452 return 1;
453 p->dotdot = dotdot;
454 e2fsck_put_dir_info(ctx, p);
455 return 0;
456 }
457
458 /*
459 * This function only sets the parent pointer, and requires that
460 * dirinfo structure has already been created.
461 */
e2fsck_dir_info_get_parent(e2fsck_t ctx,ext2_ino_t ino,ext2_ino_t * parent)462 int e2fsck_dir_info_get_parent(e2fsck_t ctx, ext2_ino_t ino,
463 ext2_ino_t *parent)
464 {
465 struct dir_info *p;
466
467 p = e2fsck_get_dir_info(ctx, ino);
468 if (!p)
469 return 1;
470 *parent = p->parent;
471 return 0;
472 }
473
474 /*
475 * This function only sets the dot dot pointer, and requires that
476 * dirinfo structure has already been created.
477 */
e2fsck_dir_info_get_dotdot(e2fsck_t ctx,ext2_ino_t ino,ext2_ino_t * dotdot)478 int e2fsck_dir_info_get_dotdot(e2fsck_t ctx, ext2_ino_t ino,
479 ext2_ino_t *dotdot)
480 {
481 struct dir_info *p;
482
483 p = e2fsck_get_dir_info(ctx, ino);
484 if (!p)
485 return 1;
486 *dotdot = p->dotdot;
487 return 0;
488 }
489
490