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