1 /*
2 * linux/fs/hfs/catalog.c
3 *
4 * Copyright (C) 1995-1997 Paul H. Hargrove
5 * (C) 2003 Ardis Technologies <roman@ardistech.com>
6 * This file may be distributed under the terms of the GNU General Public License.
7 *
8 * This file contains the functions related to the catalog B-tree.
9 *
10 * Cache code shamelessly stolen from
11 * linux/fs/inode.c Copyright (C) 1991, 1992 Linus Torvalds
12 * re-shamelessly stolen Copyright (C) 1997 Linus Torvalds
13 */
14
15 #include "hfs_fs.h"
16 #include "btree.h"
17
18 /*
19 * hfs_cat_build_key()
20 *
21 * Given the ID of the parent and the name build a search key.
22 */
hfs_cat_build_key(struct super_block * sb,btree_key * key,u32 parent,const struct qstr * name)23 void hfs_cat_build_key(struct super_block *sb, btree_key *key, u32 parent, const struct qstr *name)
24 {
25 key->cat.reserved = 0;
26 key->cat.ParID = cpu_to_be32(parent);
27 if (name) {
28 hfs_asc2mac(sb, &key->cat.CName, name);
29 key->key_len = 6 + key->cat.CName.len;
30 } else {
31 memset(&key->cat.CName, 0, sizeof(struct hfs_name));
32 key->key_len = 6;
33 }
34 }
35
hfs_cat_build_record(hfs_cat_rec * rec,u32 cnid,struct inode * inode)36 static int hfs_cat_build_record(hfs_cat_rec *rec, u32 cnid, struct inode *inode)
37 {
38 __be32 mtime = hfs_mtime();
39
40 memset(rec, 0, sizeof(*rec));
41 if (S_ISDIR(inode->i_mode)) {
42 rec->type = HFS_CDR_DIR;
43 rec->dir.DirID = cpu_to_be32(cnid);
44 rec->dir.CrDat = mtime;
45 rec->dir.MdDat = mtime;
46 rec->dir.BkDat = 0;
47 rec->dir.UsrInfo.frView = cpu_to_be16(0xff);
48 return sizeof(struct hfs_cat_dir);
49 } else {
50 /* init some fields for the file record */
51 rec->type = HFS_CDR_FIL;
52 rec->file.Flags = HFS_FIL_USED | HFS_FIL_THD;
53 if (!(inode->i_mode & S_IWUSR))
54 rec->file.Flags |= HFS_FIL_LOCK;
55 rec->file.FlNum = cpu_to_be32(cnid);
56 rec->file.CrDat = mtime;
57 rec->file.MdDat = mtime;
58 rec->file.BkDat = 0;
59 rec->file.UsrWds.fdType = HFS_SB(inode->i_sb)->s_type;
60 rec->file.UsrWds.fdCreator = HFS_SB(inode->i_sb)->s_creator;
61 return sizeof(struct hfs_cat_file);
62 }
63 }
64
hfs_cat_build_thread(struct super_block * sb,hfs_cat_rec * rec,int type,u32 parentid,const struct qstr * name)65 static int hfs_cat_build_thread(struct super_block *sb,
66 hfs_cat_rec *rec, int type,
67 u32 parentid, const struct qstr *name)
68 {
69 rec->type = type;
70 memset(rec->thread.reserved, 0, sizeof(rec->thread.reserved));
71 rec->thread.ParID = cpu_to_be32(parentid);
72 hfs_asc2mac(sb, &rec->thread.CName, name);
73 return sizeof(struct hfs_cat_thread);
74 }
75
76 /*
77 * create_entry()
78 *
79 * Add a new file or directory to the catalog B-tree and
80 * return a (struct hfs_cat_entry) for it in '*result'.
81 */
hfs_cat_create(u32 cnid,struct inode * dir,const struct qstr * str,struct inode * inode)82 int hfs_cat_create(u32 cnid, struct inode *dir, const struct qstr *str, struct inode *inode)
83 {
84 struct hfs_find_data fd;
85 struct super_block *sb;
86 union hfs_cat_rec entry;
87 int entry_size;
88 int err;
89
90 hfs_dbg("name %s, cnid %u, i_nlink %d\n",
91 str->name, cnid, inode->i_nlink);
92 if (dir->i_size >= HFS_MAX_VALENCE)
93 return -ENOSPC;
94
95 sb = dir->i_sb;
96 err = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
97 if (err)
98 return err;
99
100 /*
101 * Fail early and avoid ENOSPC during the btree operations. We may
102 * have to split the root node at most once.
103 */
104 err = hfs_bmap_reserve(fd.tree, 2 * fd.tree->depth);
105 if (err)
106 goto err2;
107
108 hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
109 entry_size = hfs_cat_build_thread(sb, &entry, S_ISDIR(inode->i_mode) ?
110 HFS_CDR_THD : HFS_CDR_FTH,
111 dir->i_ino, str);
112 err = hfs_brec_find(&fd);
113 if (err != -ENOENT) {
114 if (!err)
115 err = -EEXIST;
116 goto err2;
117 }
118 err = hfs_brec_insert(&fd, &entry, entry_size);
119 if (err)
120 goto err2;
121
122 hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
123 entry_size = hfs_cat_build_record(&entry, cnid, inode);
124 err = hfs_brec_find(&fd);
125 if (err != -ENOENT) {
126 /* panic? */
127 if (!err)
128 err = -EEXIST;
129 goto err1;
130 }
131 err = hfs_brec_insert(&fd, &entry, entry_size);
132 if (err)
133 goto err1;
134
135 dir->i_size++;
136 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
137 mark_inode_dirty(dir);
138 hfs_find_exit(&fd);
139 return 0;
140
141 err1:
142 hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
143 if (!hfs_brec_find(&fd))
144 hfs_brec_remove(&fd);
145 err2:
146 hfs_find_exit(&fd);
147 return err;
148 }
149
150 /*
151 * hfs_cat_compare()
152 *
153 * Description:
154 * This is the comparison function used for the catalog B-tree. In
155 * comparing catalog B-tree entries, the parent id is the most
156 * significant field (compared as unsigned ints). The name field is
157 * the least significant (compared in "Macintosh lexical order",
158 * see hfs_strcmp() in string.c)
159 * Input Variable(s):
160 * struct hfs_cat_key *key1: pointer to the first key to compare
161 * struct hfs_cat_key *key2: pointer to the second key to compare
162 * Output Variable(s):
163 * NONE
164 * Returns:
165 * int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
166 * Preconditions:
167 * key1 and key2 point to "valid" (struct hfs_cat_key)s.
168 * Postconditions:
169 * This function has no side-effects
170 */
hfs_cat_keycmp(const btree_key * key1,const btree_key * key2)171 int hfs_cat_keycmp(const btree_key *key1, const btree_key *key2)
172 {
173 __be32 k1p, k2p;
174
175 k1p = key1->cat.ParID;
176 k2p = key2->cat.ParID;
177
178 if (k1p != k2p)
179 return be32_to_cpu(k1p) < be32_to_cpu(k2p) ? -1 : 1;
180
181 return hfs_strcmp(key1->cat.CName.name, key1->cat.CName.len,
182 key2->cat.CName.name, key2->cat.CName.len);
183 }
184
185 /* Try to get a catalog entry for given catalog id */
186 // move to read_super???
hfs_cat_find_brec(struct super_block * sb,u32 cnid,struct hfs_find_data * fd)187 int hfs_cat_find_brec(struct super_block *sb, u32 cnid,
188 struct hfs_find_data *fd)
189 {
190 hfs_cat_rec rec;
191 int res, len, type;
192
193 hfs_cat_build_key(sb, fd->search_key, cnid, NULL);
194 res = hfs_brec_read(fd, &rec, sizeof(rec));
195 if (res)
196 return res;
197
198 type = rec.type;
199 if (type != HFS_CDR_THD && type != HFS_CDR_FTH) {
200 pr_err("found bad thread record in catalog\n");
201 return -EIO;
202 }
203
204 fd->search_key->cat.ParID = rec.thread.ParID;
205 len = fd->search_key->cat.CName.len = rec.thread.CName.len;
206 if (len > HFS_NAMELEN) {
207 pr_err("bad catalog namelength\n");
208 return -EIO;
209 }
210 memcpy(fd->search_key->cat.CName.name, rec.thread.CName.name, len);
211 return hfs_brec_find(fd);
212 }
213
214 static inline
hfs_set_next_unused_CNID(struct super_block * sb,u32 deleted_cnid,u32 found_cnid)215 void hfs_set_next_unused_CNID(struct super_block *sb,
216 u32 deleted_cnid, u32 found_cnid)
217 {
218 if (found_cnid < HFS_FIRSTUSER_CNID) {
219 atomic64_cmpxchg(&HFS_SB(sb)->next_id,
220 deleted_cnid + 1, HFS_FIRSTUSER_CNID);
221 } else {
222 atomic64_cmpxchg(&HFS_SB(sb)->next_id,
223 deleted_cnid + 1, found_cnid + 1);
224 }
225 }
226
227 /*
228 * hfs_correct_next_unused_CNID()
229 *
230 * Correct the next unused CNID of Catalog Tree.
231 */
232 static
hfs_correct_next_unused_CNID(struct super_block * sb,u32 cnid)233 int hfs_correct_next_unused_CNID(struct super_block *sb, u32 cnid)
234 {
235 struct hfs_btree *cat_tree;
236 struct hfs_bnode *node;
237 s64 leaf_head;
238 s64 leaf_tail;
239 s64 node_id;
240
241 hfs_dbg("cnid %u, next_id %lld\n",
242 cnid, atomic64_read(&HFS_SB(sb)->next_id));
243
244 if ((cnid + 1) < atomic64_read(&HFS_SB(sb)->next_id)) {
245 /* next ID should be unchanged */
246 return 0;
247 }
248
249 cat_tree = HFS_SB(sb)->cat_tree;
250 leaf_head = cat_tree->leaf_head;
251 leaf_tail = cat_tree->leaf_tail;
252
253 if (leaf_head > leaf_tail) {
254 pr_err("node is corrupted: leaf_head %lld, leaf_tail %lld\n",
255 leaf_head, leaf_tail);
256 return -ERANGE;
257 }
258
259 node = hfs_bnode_find(cat_tree, leaf_tail);
260 if (IS_ERR(node)) {
261 pr_err("fail to find leaf node: node ID %lld\n",
262 leaf_tail);
263 return -ENOENT;
264 }
265
266 node_id = leaf_tail;
267
268 do {
269 int i;
270
271 if (node_id != leaf_tail) {
272 node = hfs_bnode_find(cat_tree, node_id);
273 if (IS_ERR(node))
274 return -ENOENT;
275 }
276
277 hfs_dbg("node %lld, leaf_tail %lld, leaf_head %lld\n",
278 node_id, leaf_tail, leaf_head);
279
280 hfs_bnode_dump(node);
281
282 for (i = node->num_recs - 1; i >= 0; i--) {
283 hfs_cat_rec rec;
284 u16 off, len, keylen;
285 int entryoffset;
286 int entrylength;
287 u32 found_cnid;
288
289 len = hfs_brec_lenoff(node, i, &off);
290 keylen = hfs_brec_keylen(node, i);
291 if (keylen == 0) {
292 pr_err("fail to get the keylen: "
293 "node_id %lld, record index %d\n",
294 node_id, i);
295 return -EINVAL;
296 }
297
298 entryoffset = off + keylen;
299 entrylength = len - keylen;
300
301 if (entrylength > sizeof(rec)) {
302 pr_err("unexpected record length: "
303 "entrylength %d\n",
304 entrylength);
305 return -EINVAL;
306 }
307
308 hfs_bnode_read(node, &rec, entryoffset, entrylength);
309
310 if (rec.type == HFS_CDR_DIR) {
311 found_cnid = be32_to_cpu(rec.dir.DirID);
312 hfs_dbg("found_cnid %u\n", found_cnid);
313 hfs_set_next_unused_CNID(sb, cnid, found_cnid);
314 hfs_bnode_put(node);
315 return 0;
316 } else if (rec.type == HFS_CDR_FIL) {
317 found_cnid = be32_to_cpu(rec.file.FlNum);
318 hfs_dbg("found_cnid %u\n", found_cnid);
319 hfs_set_next_unused_CNID(sb, cnid, found_cnid);
320 hfs_bnode_put(node);
321 return 0;
322 }
323 }
324
325 hfs_bnode_put(node);
326
327 node_id = node->prev;
328 } while (node_id >= leaf_head);
329
330 return -ENOENT;
331 }
332
333 /*
334 * hfs_cat_delete()
335 *
336 * Delete the indicated file or directory.
337 * The associated thread is also removed unless ('with_thread'==0).
338 */
hfs_cat_delete(u32 cnid,struct inode * dir,const struct qstr * str)339 int hfs_cat_delete(u32 cnid, struct inode *dir, const struct qstr *str)
340 {
341 struct super_block *sb;
342 struct hfs_find_data fd;
343 struct hfs_readdir_data *rd;
344 int res, type;
345
346 hfs_dbg("name %s, cnid %u\n", str ? str->name : NULL, cnid);
347 sb = dir->i_sb;
348 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
349 if (res)
350 return res;
351
352 hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
353 res = hfs_brec_find(&fd);
354 if (res)
355 goto out;
356
357 type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
358 if (type == HFS_CDR_FIL) {
359 struct hfs_cat_file file;
360 hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
361 if (be32_to_cpu(file.FlNum) == cnid) {
362 #if 0
363 hfs_free_fork(sb, &file, HFS_FK_DATA);
364 #endif
365 hfs_free_fork(sb, &file, HFS_FK_RSRC);
366 }
367 }
368
369 /* we only need to take spinlock for exclusion with ->release() */
370 spin_lock(&HFS_I(dir)->open_dir_lock);
371 list_for_each_entry(rd, &HFS_I(dir)->open_dir_list, list) {
372 if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
373 rd->file->f_pos--;
374 }
375 spin_unlock(&HFS_I(dir)->open_dir_lock);
376
377 res = hfs_brec_remove(&fd);
378 if (res)
379 goto out;
380
381 hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
382 res = hfs_brec_find(&fd);
383 if (!res) {
384 res = hfs_brec_remove(&fd);
385 if (res)
386 goto out;
387 }
388
389 dir->i_size--;
390 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
391 mark_inode_dirty(dir);
392
393 res = hfs_correct_next_unused_CNID(sb, cnid);
394 if (res)
395 goto out;
396
397 res = 0;
398 out:
399 hfs_find_exit(&fd);
400
401 return res;
402 }
403
404 /*
405 * hfs_cat_move()
406 *
407 * Rename a file or directory, possibly to a new directory.
408 * If the destination exists it is removed and a
409 * (struct hfs_cat_entry) for it is returned in '*result'.
410 */
hfs_cat_move(u32 cnid,struct inode * src_dir,const struct qstr * src_name,struct inode * dst_dir,const struct qstr * dst_name)411 int hfs_cat_move(u32 cnid, struct inode *src_dir, const struct qstr *src_name,
412 struct inode *dst_dir, const struct qstr *dst_name)
413 {
414 struct super_block *sb;
415 struct hfs_find_data src_fd, dst_fd;
416 union hfs_cat_rec entry;
417 int entry_size, type;
418 int err;
419
420 hfs_dbg("cnid %u - (ino %lu, name %s) - (ino %lu, name %s)\n",
421 cnid, src_dir->i_ino, src_name->name,
422 dst_dir->i_ino, dst_name->name);
423 sb = src_dir->i_sb;
424 err = hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
425 if (err)
426 return err;
427 dst_fd = src_fd;
428
429 /*
430 * Fail early and avoid ENOSPC during the btree operations. We may
431 * have to split the root node at most once.
432 */
433 err = hfs_bmap_reserve(src_fd.tree, 2 * src_fd.tree->depth);
434 if (err)
435 goto out;
436
437 /* find the old dir entry and read the data */
438 hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
439 err = hfs_brec_find(&src_fd);
440 if (err)
441 goto out;
442 if (src_fd.entrylength > sizeof(entry) || src_fd.entrylength < 0) {
443 err = -EIO;
444 goto out;
445 }
446
447 hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
448 src_fd.entrylength);
449
450 /* create new dir entry with the data from the old entry */
451 hfs_cat_build_key(sb, dst_fd.search_key, dst_dir->i_ino, dst_name);
452 err = hfs_brec_find(&dst_fd);
453 if (err != -ENOENT) {
454 if (!err)
455 err = -EEXIST;
456 goto out;
457 }
458
459 err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
460 if (err)
461 goto out;
462 dst_dir->i_size++;
463 inode_set_mtime_to_ts(dst_dir, inode_set_ctime_current(dst_dir));
464 mark_inode_dirty(dst_dir);
465
466 /* finally remove the old entry */
467 hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
468 err = hfs_brec_find(&src_fd);
469 if (err)
470 goto out;
471 err = hfs_brec_remove(&src_fd);
472 if (err)
473 goto out;
474 src_dir->i_size--;
475 inode_set_mtime_to_ts(src_dir, inode_set_ctime_current(src_dir));
476 mark_inode_dirty(src_dir);
477
478 type = entry.type;
479 if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
480 goto out;
481
482 /* remove old thread entry */
483 hfs_cat_build_key(sb, src_fd.search_key, cnid, NULL);
484 err = hfs_brec_find(&src_fd);
485 if (err)
486 goto out;
487 err = hfs_brec_remove(&src_fd);
488 if (err)
489 goto out;
490
491 /* create new thread entry */
492 hfs_cat_build_key(sb, dst_fd.search_key, cnid, NULL);
493 entry_size = hfs_cat_build_thread(sb, &entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,
494 dst_dir->i_ino, dst_name);
495 err = hfs_brec_find(&dst_fd);
496 if (err != -ENOENT) {
497 if (!err)
498 err = -EEXIST;
499 goto out;
500 }
501 err = hfs_brec_insert(&dst_fd, &entry, entry_size);
502 out:
503 hfs_bnode_put(dst_fd.bnode);
504 hfs_find_exit(&src_fd);
505 return err;
506 }
507