switch d_materialise_unique() users to d_splice_alias()
[linux-2.6-block.git] / fs / affs / namei.c
CommitLineData
1da177e4
LT
1/*
2 * linux/fs/affs/namei.c
3 *
4 * (c) 1996 Hans-Joachim Widmaier - Rewritten
5 *
6 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
7 *
8 * (C) 1991 Linus Torvalds - minix filesystem
9 */
10
11#include "affs.h"
12
13typedef int (*toupper_t)(int);
14
15static int affs_toupper(int ch);
da53be12
LT
16static int affs_hash_dentry(const struct dentry *, struct qstr *);
17static int affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
621e155a 18 unsigned int len, const char *str, const struct qstr *name);
1da177e4 19static int affs_intl_toupper(int ch);
da53be12
LT
20static int affs_intl_hash_dentry(const struct dentry *, struct qstr *);
21static int affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
621e155a 22 unsigned int len, const char *str, const struct qstr *name);
1da177e4 23
e16404ed 24const struct dentry_operations affs_dentry_operations = {
1da177e4
LT
25 .d_hash = affs_hash_dentry,
26 .d_compare = affs_compare_dentry,
27};
28
a129880d 29const struct dentry_operations affs_intl_dentry_operations = {
1da177e4
LT
30 .d_hash = affs_intl_hash_dentry,
31 .d_compare = affs_intl_compare_dentry,
32};
33
34
35/* Simple toupper() for DOS\1 */
36
37static int
38affs_toupper(int ch)
39{
40 return ch >= 'a' && ch <= 'z' ? ch -= ('a' - 'A') : ch;
41}
42
43/* International toupper() for DOS\3 ("international") */
44
45static int
46affs_intl_toupper(int ch)
47{
48 return (ch >= 'a' && ch <= 'z') || (ch >= 0xE0
49 && ch <= 0xFE && ch != 0xF7) ?
50 ch - ('a' - 'A') : ch;
51}
52
53static inline toupper_t
54affs_get_toupper(struct super_block *sb)
55{
56 return AFFS_SB(sb)->s_flags & SF_INTL ? affs_intl_toupper : affs_toupper;
57}
58
59/*
60 * Note: the dentry argument is the parent dentry.
61 */
62static inline int
8ca57722 63__affs_hash_dentry(struct qstr *qstr, toupper_t toupper, bool notruncate)
1da177e4
LT
64{
65 const u8 *name = qstr->name;
66 unsigned long hash;
67 int i;
68
8ca57722 69 i = affs_check_name(qstr->name, qstr->len, notruncate);
1da177e4
LT
70 if (i)
71 return i;
72
73 hash = init_name_hash();
74 i = min(qstr->len, 30u);
75 for (; i > 0; name++, i--)
76 hash = partial_name_hash(toupper(*name), hash);
77 qstr->hash = end_name_hash(hash);
78
79 return 0;
80}
81
82static int
da53be12 83affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
1da177e4 84{
8ca57722
FF
85 return __affs_hash_dentry(qstr, affs_toupper,
86 affs_nofilenametruncate(dentry));
87
1da177e4 88}
8ca57722 89
1da177e4 90static int
da53be12 91affs_intl_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
1da177e4 92{
8ca57722
FF
93 return __affs_hash_dentry(qstr, affs_intl_toupper,
94 affs_nofilenametruncate(dentry));
95
1da177e4
LT
96}
97
621e155a 98static inline int __affs_compare_dentry(unsigned int len,
8ca57722
FF
99 const char *str, const struct qstr *name, toupper_t toupper,
100 bool notruncate)
1da177e4 101{
621e155a
NP
102 const u8 *aname = str;
103 const u8 *bname = name->name;
1da177e4 104
621e155a
NP
105 /*
106 * 'str' is the name of an already existing dentry, so the name
107 * must be valid. 'name' must be validated first.
1da177e4
LT
108 */
109
8ca57722 110 if (affs_check_name(name->name, name->len, notruncate))
1da177e4
LT
111 return 1;
112
621e155a
NP
113 /*
114 * If the names are longer than the allowed 30 chars,
1da177e4
LT
115 * the excess is ignored, so their length may differ.
116 */
1da177e4 117 if (len >= 30) {
621e155a 118 if (name->len < 30)
1da177e4
LT
119 return 1;
120 len = 30;
621e155a 121 } else if (len != name->len)
1da177e4
LT
122 return 1;
123
124 for (; len > 0; len--)
125 if (toupper(*aname++) != toupper(*bname++))
126 return 1;
127
128 return 0;
129}
130
131static int
da53be12 132affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
621e155a 133 unsigned int len, const char *str, const struct qstr *name)
1da177e4 134{
8ca57722
FF
135
136 return __affs_compare_dentry(len, str, name, affs_toupper,
137 affs_nofilenametruncate(parent));
1da177e4 138}
8ca57722 139
1da177e4 140static int
da53be12 141affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
621e155a 142 unsigned int len, const char *str, const struct qstr *name)
1da177e4 143{
8ca57722
FF
144 return __affs_compare_dentry(len, str, name, affs_intl_toupper,
145 affs_nofilenametruncate(parent));
146
1da177e4
LT
147}
148
149/*
150 * NOTE! unlike strncmp, affs_match returns 1 for success, 0 for failure.
151 */
152
153static inline int
154affs_match(struct dentry *dentry, const u8 *name2, toupper_t toupper)
155{
156 const u8 *name = dentry->d_name.name;
157 int len = dentry->d_name.len;
158
159 if (len >= 30) {
160 if (*name2 < 30)
161 return 0;
162 len = 30;
163 } else if (len != *name2)
164 return 0;
165
166 for (name2++; len > 0; len--)
167 if (toupper(*name++) != toupper(*name2++))
168 return 0;
169 return 1;
170}
171
172int
173affs_hash_name(struct super_block *sb, const u8 *name, unsigned int len)
174{
175 toupper_t toupper = affs_get_toupper(sb);
176 int hash;
177
178 hash = len = min(len, 30u);
179 for (; len > 0; len--)
180 hash = (hash * 13 + toupper(*name++)) & 0x7ff;
181
182 return hash % AFFS_SB(sb)->s_hashsize;
183}
184
185static struct buffer_head *
186affs_find_entry(struct inode *dir, struct dentry *dentry)
187{
188 struct super_block *sb = dir->i_sb;
189 struct buffer_head *bh;
190 toupper_t toupper = affs_get_toupper(sb);
191 u32 key;
192
9606d9aa
FF
193 pr_debug("%s(\"%.*s\")\n",
194 __func__, (int)dentry->d_name.len, dentry->d_name.name);
1da177e4
LT
195
196 bh = affs_bread(sb, dir->i_ino);
197 if (!bh)
198 return ERR_PTR(-EIO);
199
200 key = be32_to_cpu(AFFS_HEAD(bh)->table[affs_hash_name(sb, dentry->d_name.name, dentry->d_name.len)]);
201
202 for (;;) {
203 affs_brelse(bh);
204 if (key == 0)
205 return NULL;
206 bh = affs_bread(sb, key);
207 if (!bh)
208 return ERR_PTR(-EIO);
209 if (affs_match(dentry, AFFS_TAIL(sb, bh)->name, toupper))
210 return bh;
211 key = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
212 }
213}
214
215struct dentry *
00cd8dd3 216affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
1da177e4
LT
217{
218 struct super_block *sb = dir->i_sb;
219 struct buffer_head *bh;
220 struct inode *inode = NULL;
221
9606d9aa
FF
222 pr_debug("%s(\"%.*s\")\n",
223 __func__, (int)dentry->d_name.len, dentry->d_name.name);
1da177e4
LT
224
225 affs_lock_dir(dir);
226 bh = affs_find_entry(dir, dentry);
227 affs_unlock_dir(dir);
210f8559 228 if (IS_ERR(bh))
e231c2ee 229 return ERR_CAST(bh);
1da177e4
LT
230 if (bh) {
231 u32 ino = bh->b_blocknr;
232
233 /* store the real header ino in d_fsdata for faster lookups */
234 dentry->d_fsdata = (void *)(long)ino;
235 switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
236 //link to dirs disabled
237 //case ST_LINKDIR:
238 case ST_LINKFILE:
239 ino = be32_to_cpu(AFFS_TAIL(sb, bh)->original);
240 }
241 affs_brelse(bh);
210f8559
DH
242 inode = affs_iget(sb, ino);
243 if (IS_ERR(inode))
cccad8f9 244 return ERR_CAST(inode);
1da177e4 245 }
1da177e4
LT
246 d_add(dentry, inode);
247 return NULL;
248}
249
250int
251affs_unlink(struct inode *dir, struct dentry *dentry)
252{
9606d9aa
FF
253 pr_debug("%s(dir=%d, %lu \"%.*s\")\n",
254 __func__, (u32)dir->i_ino, dentry->d_inode->i_ino,
255 (int)dentry->d_name.len, dentry->d_name.name);
1da177e4
LT
256
257 return affs_remove_header(dentry);
258}
259
260int
ebfc3b49 261affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
1da177e4
LT
262{
263 struct super_block *sb = dir->i_sb;
264 struct inode *inode;
265 int error;
266
9606d9aa
FF
267 pr_debug("%s(%lu,\"%.*s\",0%ho)\n",
268 __func__, dir->i_ino, (int)dentry->d_name.len,
1da177e4
LT
269 dentry->d_name.name,mode);
270
271 inode = affs_new_inode(dir);
272 if (!inode)
273 return -ENOSPC;
274
275 inode->i_mode = mode;
276 mode_to_prot(inode);
277 mark_inode_dirty(inode);
278
279 inode->i_op = &affs_file_inode_operations;
280 inode->i_fop = &affs_file_operations;
281 inode->i_mapping->a_ops = (AFFS_SB(sb)->s_flags & SF_OFS) ? &affs_aops_ofs : &affs_aops;
282 error = affs_add_entry(dir, inode, dentry, ST_FILE);
283 if (error) {
6d6b77f1 284 clear_nlink(inode);
1da177e4
LT
285 iput(inode);
286 return error;
287 }
288 return 0;
289}
290
291int
18bb1db3 292affs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1da177e4
LT
293{
294 struct inode *inode;
295 int error;
296
9606d9aa
FF
297 pr_debug("%s(%lu,\"%.*s\",0%ho)\n",
298 __func__, dir->i_ino, (int)dentry->d_name.len,
299 dentry->d_name.name, mode);
1da177e4
LT
300
301 inode = affs_new_inode(dir);
302 if (!inode)
303 return -ENOSPC;
304
305 inode->i_mode = S_IFDIR | mode;
306 mode_to_prot(inode);
307
308 inode->i_op = &affs_dir_inode_operations;
309 inode->i_fop = &affs_dir_operations;
310
311 error = affs_add_entry(dir, inode, dentry, ST_USERDIR);
312 if (error) {
6d6b77f1 313 clear_nlink(inode);
1da177e4
LT
314 mark_inode_dirty(inode);
315 iput(inode);
316 return error;
317 }
318 return 0;
319}
320
321int
322affs_rmdir(struct inode *dir, struct dentry *dentry)
323{
9606d9aa
FF
324 pr_debug("%s(dir=%u, %lu \"%.*s\")\n",
325 __func__, (u32)dir->i_ino, dentry->d_inode->i_ino,
1da177e4
LT
326 (int)dentry->d_name.len, dentry->d_name.name);
327
328 return affs_remove_header(dentry);
329}
330
331int
332affs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
333{
334 struct super_block *sb = dir->i_sb;
335 struct buffer_head *bh;
336 struct inode *inode;
337 char *p;
338 int i, maxlen, error;
339 char c, lc;
340
9606d9aa
FF
341 pr_debug("%s(%lu,\"%.*s\" -> \"%s\")\n",
342 __func__, dir->i_ino, (int)dentry->d_name.len,
343 dentry->d_name.name, symname);
1da177e4
LT
344
345 maxlen = AFFS_SB(sb)->s_hashsize * sizeof(u32) - 1;
346 inode = affs_new_inode(dir);
347 if (!inode)
348 return -ENOSPC;
349
350 inode->i_op = &affs_symlink_inode_operations;
351 inode->i_data.a_ops = &affs_symlink_aops;
352 inode->i_mode = S_IFLNK | 0777;
353 mode_to_prot(inode);
354
355 error = -EIO;
356 bh = affs_bread(sb, inode->i_ino);
357 if (!bh)
358 goto err;
359 i = 0;
360 p = (char *)AFFS_HEAD(bh)->table;
361 lc = '/';
362 if (*symname == '/') {
29333920 363 struct affs_sb_info *sbi = AFFS_SB(sb);
1da177e4
LT
364 while (*symname == '/')
365 symname++;
29333920
AV
366 spin_lock(&sbi->symlink_lock);
367 while (sbi->s_volume[i]) /* Cannot overflow */
368 *p++ = sbi->s_volume[i++];
369 spin_unlock(&sbi->symlink_lock);
1da177e4
LT
370 }
371 while (i < maxlen && (c = *symname++)) {
372 if (c == '.' && lc == '/' && *symname == '.' && symname[1] == '/') {
373 *p++ = '/';
374 i++;
375 symname += 2;
376 lc = '/';
377 } else if (c == '.' && lc == '/' && *symname == '/') {
378 symname++;
379 lc = '/';
380 } else {
381 *p++ = c;
382 lc = c;
383 i++;
384 }
385 if (lc == '/')
386 while (*symname == '/')
387 symname++;
388 }
389 *p = 0;
390 mark_buffer_dirty_inode(bh, inode);
391 affs_brelse(bh);
392 mark_inode_dirty(inode);
393
394 error = affs_add_entry(dir, inode, dentry, ST_SOFTLINK);
395 if (error)
396 goto err;
397
398 return 0;
399
400err:
6d6b77f1 401 clear_nlink(inode);
1da177e4
LT
402 mark_inode_dirty(inode);
403 iput(inode);
404 return error;
405}
406
407int
408affs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
409{
410 struct inode *inode = old_dentry->d_inode;
411
9606d9aa
FF
412 pr_debug("%s(%u, %u, \"%.*s\")\n",
413 __func__, (u32)inode->i_ino, (u32)dir->i_ino,
1da177e4
LT
414 (int)dentry->d_name.len,dentry->d_name.name);
415
416 return affs_add_entry(dir, inode, dentry, ST_LINKFILE);
417}
418
419int
420affs_rename(struct inode *old_dir, struct dentry *old_dentry,
421 struct inode *new_dir, struct dentry *new_dentry)
422{
423 struct super_block *sb = old_dir->i_sb;
424 struct buffer_head *bh = NULL;
425 int retval;
426
9606d9aa
FF
427 pr_debug("%s(old=%u,\"%*s\" to new=%u,\"%*s\")\n",
428 __func__, (u32)old_dir->i_ino, (int)old_dentry->d_name.len,
429 old_dentry->d_name.name, (u32)new_dir->i_ino,
430 (int)new_dentry->d_name.len, new_dentry->d_name.name);
1da177e4 431
8ca57722
FF
432 retval = affs_check_name(new_dentry->d_name.name,
433 new_dentry->d_name.len,
434 affs_nofilenametruncate(old_dentry));
435
1da177e4
LT
436 if (retval)
437 return retval;
438
439 /* Unlink destination if it already exists */
440 if (new_dentry->d_inode) {
441 retval = affs_remove_header(new_dentry);
442 if (retval)
443 return retval;
444 }
445
1da177e4
LT
446 bh = affs_bread(sb, old_dentry->d_inode->i_ino);
447 if (!bh)
3ac81413 448 return -EIO;
1da177e4
LT
449
450 /* Remove header from its parent directory. */
451 affs_lock_dir(old_dir);
452 retval = affs_remove_hash(old_dir, bh);
453 affs_unlock_dir(old_dir);
454 if (retval)
455 goto done;
456
457 /* And insert it into the new directory with the new name. */
458 affs_copy_name(AFFS_TAIL(sb, bh)->name, new_dentry);
459 affs_fix_checksum(sb, bh);
460 affs_lock_dir(new_dir);
461 retval = affs_insert_hash(new_dir, bh);
462 affs_unlock_dir(new_dir);
463 /* TODO: move it back to old_dir, if error? */
464
465done:
466 mark_buffer_dirty_inode(bh, retval ? old_dir : new_dir);
467 affs_brelse(bh);
468 return retval;
469}