xref: /openbmc/linux/fs/hfs/catalog.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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(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_triv2mac(&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(hfs_cat_rec *rec, int type,
66 				u32 parentid, struct qstr *name)
67 {
68 	rec->type = type;
69 	memset(rec->thread.reserved, 0, sizeof(rec->thread.reserved));
70 	rec->thread.ParID = cpu_to_be32(parentid);
71 	hfs_triv2mac(&rec->thread.CName, name);
72 	return sizeof(struct hfs_cat_thread);
73 }
74 
75 /*
76  * create_entry()
77  *
78  * Add a new file or directory to the catalog B-tree and
79  * return a (struct hfs_cat_entry) for it in '*result'.
80  */
81 int hfs_cat_create(u32 cnid, struct inode *dir, struct qstr *str, struct inode *inode)
82 {
83 	struct hfs_find_data fd;
84 	struct super_block *sb;
85 	union hfs_cat_rec entry;
86 	int entry_size;
87 	int err;
88 
89 	dprint(DBG_CAT_MOD, "create_cat: %s,%u(%d)\n", str->name, cnid, inode->i_nlink);
90 	if (dir->i_size >= HFS_MAX_VALENCE)
91 		return -ENOSPC;
92 
93 	sb = dir->i_sb;
94 	hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
95 
96 	hfs_cat_build_key(fd.search_key, cnid, NULL);
97 	entry_size = hfs_cat_build_thread(&entry, S_ISDIR(inode->i_mode) ?
98 			HFS_CDR_THD : HFS_CDR_FTH,
99 			dir->i_ino, str);
100 	err = hfs_brec_find(&fd);
101 	if (err != -ENOENT) {
102 		if (!err)
103 			err = -EEXIST;
104 		goto err2;
105 	}
106 	err = hfs_brec_insert(&fd, &entry, entry_size);
107 	if (err)
108 		goto err2;
109 
110 	hfs_cat_build_key(fd.search_key, dir->i_ino, str);
111 	entry_size = hfs_cat_build_record(&entry, cnid, inode);
112 	err = hfs_brec_find(&fd);
113 	if (err != -ENOENT) {
114 		/* panic? */
115 		if (!err)
116 			err = -EEXIST;
117 		goto err1;
118 	}
119 	err = hfs_brec_insert(&fd, &entry, entry_size);
120 	if (err)
121 		goto err1;
122 
123 	dir->i_size++;
124 	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
125 	mark_inode_dirty(dir);
126 	hfs_find_exit(&fd);
127 	return 0;
128 
129 err1:
130 	hfs_cat_build_key(fd.search_key, cnid, NULL);
131 	if (!hfs_brec_find(&fd))
132 		hfs_brec_remove(&fd);
133 err2:
134 	hfs_find_exit(&fd);
135 	return err;
136 }
137 
138 /*
139  * hfs_cat_compare()
140  *
141  * Description:
142  *   This is the comparison function used for the catalog B-tree.  In
143  *   comparing catalog B-tree entries, the parent id is the most
144  *   significant field (compared as unsigned ints).  The name field is
145  *   the least significant (compared in "Macintosh lexical order",
146  *   see hfs_strcmp() in string.c)
147  * Input Variable(s):
148  *   struct hfs_cat_key *key1: pointer to the first key to compare
149  *   struct hfs_cat_key *key2: pointer to the second key to compare
150  * Output Variable(s):
151  *   NONE
152  * Returns:
153  *   int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
154  * Preconditions:
155  *   key1 and key2 point to "valid" (struct hfs_cat_key)s.
156  * Postconditions:
157  *   This function has no side-effects
158  */
159 int hfs_cat_keycmp(const btree_key *key1, const btree_key *key2)
160 {
161 	int retval;
162 
163 	retval = be32_to_cpu(key1->cat.ParID) - be32_to_cpu(key2->cat.ParID);
164 	if (!retval)
165 		retval = hfs_strcmp(key1->cat.CName.name, key1->cat.CName.len,
166 				    key2->cat.CName.name, key2->cat.CName.len);
167 
168 	return retval;
169 }
170 
171 /* Try to get a catalog entry for given catalog id */
172 // move to read_super???
173 int hfs_cat_find_brec(struct super_block *sb, u32 cnid,
174 		      struct hfs_find_data *fd)
175 {
176 	hfs_cat_rec rec;
177 	int res, len, type;
178 
179 	hfs_cat_build_key(fd->search_key, cnid, NULL);
180 	res = hfs_brec_read(fd, &rec, sizeof(rec));
181 	if (res)
182 		return res;
183 
184 	type = rec.type;
185 	if (type != HFS_CDR_THD && type != HFS_CDR_FTH) {
186 		printk("HFS-fs: Found bad thread record in catalog\n");
187 		return -EIO;
188 	}
189 
190 	fd->search_key->cat.ParID = rec.thread.ParID;
191 	len = fd->search_key->cat.CName.len = rec.thread.CName.len;
192 	memcpy(fd->search_key->cat.CName.name, rec.thread.CName.name, len);
193 	return hfs_brec_find(fd);
194 }
195 
196 
197 /*
198  * hfs_cat_delete()
199  *
200  * Delete the indicated file or directory.
201  * The associated thread is also removed unless ('with_thread'==0).
202  */
203 int hfs_cat_delete(u32 cnid, struct inode *dir, struct qstr *str)
204 {
205 	struct super_block *sb;
206 	struct hfs_find_data fd;
207 	struct list_head *pos;
208 	int res, type;
209 
210 	dprint(DBG_CAT_MOD, "delete_cat: %s,%u\n", str ? str->name : NULL, cnid);
211 	sb = dir->i_sb;
212 	hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
213 
214 	hfs_cat_build_key(fd.search_key, dir->i_ino, str);
215 	res = hfs_brec_find(&fd);
216 	if (res)
217 		goto out;
218 
219 	type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
220 	if (type == HFS_CDR_FIL) {
221 		struct hfs_cat_file file;
222 		hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
223 		if (be32_to_cpu(file.FlNum) == cnid) {
224 #if 0
225 			hfs_free_fork(sb, &file, HFS_FK_DATA);
226 #endif
227 			hfs_free_fork(sb, &file, HFS_FK_RSRC);
228 		}
229 	}
230 
231 	list_for_each(pos, &HFS_I(dir)->open_dir_list) {
232 		struct hfs_readdir_data *rd =
233 			list_entry(pos, struct hfs_readdir_data, list);
234 		if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
235 			rd->file->f_pos--;
236 	}
237 
238 	res = hfs_brec_remove(&fd);
239 	if (res)
240 		goto out;
241 
242 	hfs_cat_build_key(fd.search_key, cnid, NULL);
243 	res = hfs_brec_find(&fd);
244 	if (!res) {
245 		res = hfs_brec_remove(&fd);
246 		if (res)
247 			goto out;
248 	}
249 
250 	dir->i_size--;
251 	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
252 	mark_inode_dirty(dir);
253 	res = 0;
254 out:
255 	hfs_find_exit(&fd);
256 
257 	return res;
258 }
259 
260 /*
261  * hfs_cat_move()
262  *
263  * Rename a file or directory, possibly to a new directory.
264  * If the destination exists it is removed and a
265  * (struct hfs_cat_entry) for it is returned in '*result'.
266  */
267 int hfs_cat_move(u32 cnid, struct inode *src_dir, struct qstr *src_name,
268 		 struct inode *dst_dir, struct qstr *dst_name)
269 {
270 	struct super_block *sb;
271 	struct hfs_find_data src_fd, dst_fd;
272 	union hfs_cat_rec entry;
273 	int entry_size, type;
274 	int err;
275 
276 	dprint(DBG_CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n", cnid, src_dir->i_ino, src_name->name,
277 		dst_dir->i_ino, dst_name->name);
278 	sb = src_dir->i_sb;
279 	hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
280 	dst_fd = src_fd;
281 
282 	/* find the old dir entry and read the data */
283 	hfs_cat_build_key(src_fd.search_key, src_dir->i_ino, src_name);
284 	err = hfs_brec_find(&src_fd);
285 	if (err)
286 		goto out;
287 
288 	hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
289 			    src_fd.entrylength);
290 
291 	/* create new dir entry with the data from the old entry */
292 	hfs_cat_build_key(dst_fd.search_key, dst_dir->i_ino, dst_name);
293 	err = hfs_brec_find(&dst_fd);
294 	if (err != -ENOENT) {
295 		if (!err)
296 			err = -EEXIST;
297 		goto out;
298 	}
299 
300 	err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
301 	if (err)
302 		goto out;
303 	dst_dir->i_size++;
304 	dst_dir->i_mtime = dst_dir->i_ctime = CURRENT_TIME_SEC;
305 	mark_inode_dirty(dst_dir);
306 
307 	/* finally remove the old entry */
308 	hfs_cat_build_key(src_fd.search_key, src_dir->i_ino, src_name);
309 	err = hfs_brec_find(&src_fd);
310 	if (err)
311 		goto out;
312 	err = hfs_brec_remove(&src_fd);
313 	if (err)
314 		goto out;
315 	src_dir->i_size--;
316 	src_dir->i_mtime = src_dir->i_ctime = CURRENT_TIME_SEC;
317 	mark_inode_dirty(src_dir);
318 
319 	type = entry.type;
320 	if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
321 		goto out;
322 
323 	/* remove old thread entry */
324 	hfs_cat_build_key(src_fd.search_key, cnid, NULL);
325 	err = hfs_brec_find(&src_fd);
326 	if (err)
327 		goto out;
328 	err = hfs_brec_remove(&src_fd);
329 	if (err)
330 		goto out;
331 
332 	/* create new thread entry */
333 	hfs_cat_build_key(dst_fd.search_key, cnid, NULL);
334 	entry_size = hfs_cat_build_thread(&entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,
335 					dst_dir->i_ino, dst_name);
336 	err = hfs_brec_find(&dst_fd);
337 	if (err != -ENOENT) {
338 		if (!err)
339 			err = -EEXIST;
340 		goto out;
341 	}
342 	err = hfs_brec_insert(&dst_fd, &entry, entry_size);
343 out:
344 	hfs_bnode_put(dst_fd.bnode);
345 	hfs_find_exit(&src_fd);
346 	return err;
347 }
348