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