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 */
23void 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
36static 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
65static 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 */
82int 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	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
141err1:
142	hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
143	if (!hfs_brec_find(&fd))
144		hfs_brec_remove(&fd);
145err2:
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 */
171int 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???
187int 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 */
221int 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	inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
273	mark_inode_dirty(dir);
274	res = 0;
275out:
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 */
288int 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	inode_set_mtime_to_ts(dst_dir, 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	inode_set_mtime_to_ts(src_dir, 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);
379out:
380	hfs_bnode_put(dst_fd.bnode);
381	hfs_find_exit(&src_fd);
382	return err;
383}
384