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(CAT_MOD, "create_cat: %s,%u(%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 dir->i_mtime = 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
215 /*
216 * hfs_cat_delete()
217 *
218 * Delete the indicated file or directory.
219 * The associated thread is also removed unless ('with_thread'==0).
220 */
hfs_cat_delete(u32 cnid,struct inode * dir,const struct qstr * str)221 int hfs_cat_delete(u32 cnid, struct inode *dir, const struct qstr *str)
222 {
223 struct super_block *sb;
224 struct hfs_find_data fd;
225 struct hfs_readdir_data *rd;
226 int res, type;
227
228 hfs_dbg(CAT_MOD, "delete_cat: %s,%u\n", str ? str->name : NULL, cnid);
229 sb = dir->i_sb;
230 res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
231 if (res)
232 return res;
233
234 hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
235 res = hfs_brec_find(&fd);
236 if (res)
237 goto out;
238
239 type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
240 if (type == HFS_CDR_FIL) {
241 struct hfs_cat_file file;
242 hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
243 if (be32_to_cpu(file.FlNum) == cnid) {
244 #if 0
245 hfs_free_fork(sb, &file, HFS_FK_DATA);
246 #endif
247 hfs_free_fork(sb, &file, HFS_FK_RSRC);
248 }
249 }
250
251 /* we only need to take spinlock for exclusion with ->release() */
252 spin_lock(&HFS_I(dir)->open_dir_lock);
253 list_for_each_entry(rd, &HFS_I(dir)->open_dir_list, list) {
254 if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
255 rd->file->f_pos--;
256 }
257 spin_unlock(&HFS_I(dir)->open_dir_lock);
258
259 res = hfs_brec_remove(&fd);
260 if (res)
261 goto out;
262
263 hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
264 res = hfs_brec_find(&fd);
265 if (!res) {
266 res = hfs_brec_remove(&fd);
267 if (res)
268 goto out;
269 }
270
271 dir->i_size--;
272 dir->i_mtime = inode_set_ctime_current(dir);
273 mark_inode_dirty(dir);
274 res = 0;
275 out:
276 hfs_find_exit(&fd);
277
278 return res;
279 }
280
281 /*
282 * hfs_cat_move()
283 *
284 * Rename a file or directory, possibly to a new directory.
285 * If the destination exists it is removed and a
286 * (struct hfs_cat_entry) for it is returned in '*result'.
287 */
hfs_cat_move(u32 cnid,struct inode * src_dir,const struct qstr * src_name,struct inode * dst_dir,const struct qstr * dst_name)288 int hfs_cat_move(u32 cnid, struct inode *src_dir, const struct qstr *src_name,
289 struct inode *dst_dir, const struct qstr *dst_name)
290 {
291 struct super_block *sb;
292 struct hfs_find_data src_fd, dst_fd;
293 union hfs_cat_rec entry;
294 int entry_size, type;
295 int err;
296
297 hfs_dbg(CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n",
298 cnid, src_dir->i_ino, src_name->name,
299 dst_dir->i_ino, dst_name->name);
300 sb = src_dir->i_sb;
301 err = hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
302 if (err)
303 return err;
304 dst_fd = src_fd;
305
306 /*
307 * Fail early and avoid ENOSPC during the btree operations. We may
308 * have to split the root node at most once.
309 */
310 err = hfs_bmap_reserve(src_fd.tree, 2 * src_fd.tree->depth);
311 if (err)
312 goto out;
313
314 /* find the old dir entry and read the data */
315 hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
316 err = hfs_brec_find(&src_fd);
317 if (err)
318 goto out;
319 if (src_fd.entrylength > sizeof(entry) || src_fd.entrylength < 0) {
320 err = -EIO;
321 goto out;
322 }
323
324 hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
325 src_fd.entrylength);
326
327 /* create new dir entry with the data from the old entry */
328 hfs_cat_build_key(sb, dst_fd.search_key, dst_dir->i_ino, dst_name);
329 err = hfs_brec_find(&dst_fd);
330 if (err != -ENOENT) {
331 if (!err)
332 err = -EEXIST;
333 goto out;
334 }
335
336 err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
337 if (err)
338 goto out;
339 dst_dir->i_size++;
340 dst_dir->i_mtime = inode_set_ctime_current(dst_dir);
341 mark_inode_dirty(dst_dir);
342
343 /* finally remove the old entry */
344 hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
345 err = hfs_brec_find(&src_fd);
346 if (err)
347 goto out;
348 err = hfs_brec_remove(&src_fd);
349 if (err)
350 goto out;
351 src_dir->i_size--;
352 src_dir->i_mtime = inode_set_ctime_current(src_dir);
353 mark_inode_dirty(src_dir);
354
355 type = entry.type;
356 if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
357 goto out;
358
359 /* remove old thread entry */
360 hfs_cat_build_key(sb, src_fd.search_key, cnid, NULL);
361 err = hfs_brec_find(&src_fd);
362 if (err)
363 goto out;
364 err = hfs_brec_remove(&src_fd);
365 if (err)
366 goto out;
367
368 /* create new thread entry */
369 hfs_cat_build_key(sb, dst_fd.search_key, cnid, NULL);
370 entry_size = hfs_cat_build_thread(sb, &entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,
371 dst_dir->i_ino, dst_name);
372 err = hfs_brec_find(&dst_fd);
373 if (err != -ENOENT) {
374 if (!err)
375 err = -EEXIST;
376 goto out;
377 }
378 err = hfs_brec_insert(&dst_fd, &entry, entry_size);
379 out:
380 hfs_bnode_put(dst_fd.bnode);
381 hfs_find_exit(&src_fd);
382 return err;
383 }
384