xref: /openbmc/linux/fs/hfs/catalog.c (revision 367b8112)
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  */
23 void hfs_cat_build_key(struct super_block *sb, btree_key *key, u32 parent, 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 
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 
65 static int hfs_cat_build_thread(struct super_block *sb,
66 				hfs_cat_rec *rec, int type,
67 				u32 parentid, 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  */
82 int hfs_cat_create(u32 cnid, struct inode *dir, 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 	dprint(DBG_CAT_MOD, "create_cat: %s,%u(%d)\n", str->name, cnid, inode->i_nlink);
91 	if (dir->i_size >= HFS_MAX_VALENCE)
92 		return -ENOSPC;
93 
94 	sb = dir->i_sb;
95 	hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
96 
97 	hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
98 	entry_size = hfs_cat_build_thread(sb, &entry, S_ISDIR(inode->i_mode) ?
99 			HFS_CDR_THD : HFS_CDR_FTH,
100 			dir->i_ino, str);
101 	err = hfs_brec_find(&fd);
102 	if (err != -ENOENT) {
103 		if (!err)
104 			err = -EEXIST;
105 		goto err2;
106 	}
107 	err = hfs_brec_insert(&fd, &entry, entry_size);
108 	if (err)
109 		goto err2;
110 
111 	hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
112 	entry_size = hfs_cat_build_record(&entry, cnid, inode);
113 	err = hfs_brec_find(&fd);
114 	if (err != -ENOENT) {
115 		/* panic? */
116 		if (!err)
117 			err = -EEXIST;
118 		goto err1;
119 	}
120 	err = hfs_brec_insert(&fd, &entry, entry_size);
121 	if (err)
122 		goto err1;
123 
124 	dir->i_size++;
125 	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
126 	mark_inode_dirty(dir);
127 	hfs_find_exit(&fd);
128 	return 0;
129 
130 err1:
131 	hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
132 	if (!hfs_brec_find(&fd))
133 		hfs_brec_remove(&fd);
134 err2:
135 	hfs_find_exit(&fd);
136 	return err;
137 }
138 
139 /*
140  * hfs_cat_compare()
141  *
142  * Description:
143  *   This is the comparison function used for the catalog B-tree.  In
144  *   comparing catalog B-tree entries, the parent id is the most
145  *   significant field (compared as unsigned ints).  The name field is
146  *   the least significant (compared in "Macintosh lexical order",
147  *   see hfs_strcmp() in string.c)
148  * Input Variable(s):
149  *   struct hfs_cat_key *key1: pointer to the first key to compare
150  *   struct hfs_cat_key *key2: pointer to the second key to compare
151  * Output Variable(s):
152  *   NONE
153  * Returns:
154  *   int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
155  * Preconditions:
156  *   key1 and key2 point to "valid" (struct hfs_cat_key)s.
157  * Postconditions:
158  *   This function has no side-effects
159  */
160 int hfs_cat_keycmp(const btree_key *key1, const btree_key *key2)
161 {
162 	int retval;
163 
164 	retval = be32_to_cpu(key1->cat.ParID) - be32_to_cpu(key2->cat.ParID);
165 	if (!retval)
166 		retval = hfs_strcmp(key1->cat.CName.name, key1->cat.CName.len,
167 				    key2->cat.CName.name, key2->cat.CName.len);
168 
169 	return retval;
170 }
171 
172 /* Try to get a catalog entry for given catalog id */
173 // move to read_super???
174 int hfs_cat_find_brec(struct super_block *sb, u32 cnid,
175 		      struct hfs_find_data *fd)
176 {
177 	hfs_cat_rec rec;
178 	int res, len, type;
179 
180 	hfs_cat_build_key(sb, fd->search_key, cnid, NULL);
181 	res = hfs_brec_read(fd, &rec, sizeof(rec));
182 	if (res)
183 		return res;
184 
185 	type = rec.type;
186 	if (type != HFS_CDR_THD && type != HFS_CDR_FTH) {
187 		printk(KERN_ERR "hfs: found bad thread record in catalog\n");
188 		return -EIO;
189 	}
190 
191 	fd->search_key->cat.ParID = rec.thread.ParID;
192 	len = fd->search_key->cat.CName.len = rec.thread.CName.len;
193 	if (len > HFS_NAMELEN) {
194 		printk(KERN_ERR "hfs: bad catalog namelength\n");
195 		return -EIO;
196 	}
197 	memcpy(fd->search_key->cat.CName.name, rec.thread.CName.name, len);
198 	return hfs_brec_find(fd);
199 }
200 
201 
202 /*
203  * hfs_cat_delete()
204  *
205  * Delete the indicated file or directory.
206  * The associated thread is also removed unless ('with_thread'==0).
207  */
208 int hfs_cat_delete(u32 cnid, struct inode *dir, struct qstr *str)
209 {
210 	struct super_block *sb;
211 	struct hfs_find_data fd;
212 	struct list_head *pos;
213 	int res, type;
214 
215 	dprint(DBG_CAT_MOD, "delete_cat: %s,%u\n", str ? str->name : NULL, cnid);
216 	sb = dir->i_sb;
217 	hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
218 
219 	hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);
220 	res = hfs_brec_find(&fd);
221 	if (res)
222 		goto out;
223 
224 	type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
225 	if (type == HFS_CDR_FIL) {
226 		struct hfs_cat_file file;
227 		hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
228 		if (be32_to_cpu(file.FlNum) == cnid) {
229 #if 0
230 			hfs_free_fork(sb, &file, HFS_FK_DATA);
231 #endif
232 			hfs_free_fork(sb, &file, HFS_FK_RSRC);
233 		}
234 	}
235 
236 	list_for_each(pos, &HFS_I(dir)->open_dir_list) {
237 		struct hfs_readdir_data *rd =
238 			list_entry(pos, struct hfs_readdir_data, list);
239 		if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
240 			rd->file->f_pos--;
241 	}
242 
243 	res = hfs_brec_remove(&fd);
244 	if (res)
245 		goto out;
246 
247 	hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
248 	res = hfs_brec_find(&fd);
249 	if (!res) {
250 		res = hfs_brec_remove(&fd);
251 		if (res)
252 			goto out;
253 	}
254 
255 	dir->i_size--;
256 	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
257 	mark_inode_dirty(dir);
258 	res = 0;
259 out:
260 	hfs_find_exit(&fd);
261 
262 	return res;
263 }
264 
265 /*
266  * hfs_cat_move()
267  *
268  * Rename a file or directory, possibly to a new directory.
269  * If the destination exists it is removed and a
270  * (struct hfs_cat_entry) for it is returned in '*result'.
271  */
272 int hfs_cat_move(u32 cnid, struct inode *src_dir, struct qstr *src_name,
273 		 struct inode *dst_dir, struct qstr *dst_name)
274 {
275 	struct super_block *sb;
276 	struct hfs_find_data src_fd, dst_fd;
277 	union hfs_cat_rec entry;
278 	int entry_size, type;
279 	int err;
280 
281 	dprint(DBG_CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n", cnid, src_dir->i_ino, src_name->name,
282 		dst_dir->i_ino, dst_name->name);
283 	sb = src_dir->i_sb;
284 	hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
285 	dst_fd = src_fd;
286 
287 	/* find the old dir entry and read the data */
288 	hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
289 	err = hfs_brec_find(&src_fd);
290 	if (err)
291 		goto out;
292 
293 	hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
294 			    src_fd.entrylength);
295 
296 	/* create new dir entry with the data from the old entry */
297 	hfs_cat_build_key(sb, dst_fd.search_key, dst_dir->i_ino, dst_name);
298 	err = hfs_brec_find(&dst_fd);
299 	if (err != -ENOENT) {
300 		if (!err)
301 			err = -EEXIST;
302 		goto out;
303 	}
304 
305 	err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
306 	if (err)
307 		goto out;
308 	dst_dir->i_size++;
309 	dst_dir->i_mtime = dst_dir->i_ctime = CURRENT_TIME_SEC;
310 	mark_inode_dirty(dst_dir);
311 
312 	/* finally remove the old entry */
313 	hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);
314 	err = hfs_brec_find(&src_fd);
315 	if (err)
316 		goto out;
317 	err = hfs_brec_remove(&src_fd);
318 	if (err)
319 		goto out;
320 	src_dir->i_size--;
321 	src_dir->i_mtime = src_dir->i_ctime = CURRENT_TIME_SEC;
322 	mark_inode_dirty(src_dir);
323 
324 	type = entry.type;
325 	if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
326 		goto out;
327 
328 	/* remove old thread entry */
329 	hfs_cat_build_key(sb, src_fd.search_key, cnid, NULL);
330 	err = hfs_brec_find(&src_fd);
331 	if (err)
332 		goto out;
333 	err = hfs_brec_remove(&src_fd);
334 	if (err)
335 		goto out;
336 
337 	/* create new thread entry */
338 	hfs_cat_build_key(sb, dst_fd.search_key, cnid, NULL);
339 	entry_size = hfs_cat_build_thread(sb, &entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,
340 					dst_dir->i_ino, dst_name);
341 	err = hfs_brec_find(&dst_fd);
342 	if (err != -ENOENT) {
343 		if (!err)
344 			err = -EEXIST;
345 		goto out;
346 	}
347 	err = hfs_brec_insert(&dst_fd, &entry, entry_size);
348 out:
349 	hfs_bnode_put(dst_fd.bnode);
350 	hfs_find_exit(&src_fd);
351 	return err;
352 }
353