1 // SPDX-License-Identifier: GPL-2.0
3 * linux/fs/affs/namei.c
5 * (c) 1996 Hans-Joachim Widmaier - Rewritten
7 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
9 * (C) 1991 Linus Torvalds - minix filesystem
13 #include <linux/exportfs.h>
15 typedef int (*toupper_t)(int);
17 /* Simple toupper() for DOS\1 */
22 return ch >= 'a' && ch <= 'z' ? ch -= ('a' - 'A') : ch;
25 /* International toupper() for DOS\3 ("international") */
28 affs_intl_toupper(int ch)
30 return (ch >= 'a' && ch <= 'z') || (ch >= 0xE0
31 && ch <= 0xFE && ch != 0xF7) ?
32 ch - ('a' - 'A') : ch;
35 static inline toupper_t
36 affs_get_toupper(struct super_block *sb)
38 return affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL) ?
39 affs_intl_toupper : affs_toupper;
43 * Note: the dentry argument is the parent dentry.
46 __affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr, toupper_t toupper, bool notruncate)
48 const u8 *name = qstr->name;
53 retval = affs_check_name(qstr->name, qstr->len, notruncate);
57 hash = init_name_hash(dentry);
58 len = min(qstr->len, AFFSNAMEMAX);
59 for (; len > 0; name++, len--)
60 hash = partial_name_hash(toupper(*name), hash);
61 qstr->hash = end_name_hash(hash);
67 affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
69 return __affs_hash_dentry(dentry, qstr, affs_toupper,
70 affs_nofilenametruncate(dentry));
75 affs_intl_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
77 return __affs_hash_dentry(dentry, qstr, affs_intl_toupper,
78 affs_nofilenametruncate(dentry));
82 static inline int __affs_compare_dentry(unsigned int len,
83 const char *str, const struct qstr *name, toupper_t toupper,
86 const u8 *aname = str;
87 const u8 *bname = name->name;
90 * 'str' is the name of an already existing dentry, so the name
91 * must be valid. 'name' must be validated first.
94 if (affs_check_name(name->name, name->len, notruncate))
98 * If the names are longer than the allowed 30 chars,
99 * the excess is ignored, so their length may differ.
101 if (len >= AFFSNAMEMAX) {
102 if (name->len < AFFSNAMEMAX)
105 } else if (len != name->len)
108 for (; len > 0; len--)
109 if (toupper(*aname++) != toupper(*bname++))
116 affs_compare_dentry(const struct dentry *dentry,
117 unsigned int len, const char *str, const struct qstr *name)
120 return __affs_compare_dentry(len, str, name, affs_toupper,
121 affs_nofilenametruncate(dentry));
125 affs_intl_compare_dentry(const struct dentry *dentry,
126 unsigned int len, const char *str, const struct qstr *name)
128 return __affs_compare_dentry(len, str, name, affs_intl_toupper,
129 affs_nofilenametruncate(dentry));
134 * NOTE! unlike strncmp, affs_match returns 1 for success, 0 for failure.
138 affs_match(struct dentry *dentry, const u8 *name2, toupper_t toupper)
140 const u8 *name = dentry->d_name.name;
141 int len = dentry->d_name.len;
143 if (len >= AFFSNAMEMAX) {
144 if (*name2 < AFFSNAMEMAX)
147 } else if (len != *name2)
150 for (name2++; len > 0; len--)
151 if (toupper(*name++) != toupper(*name2++))
157 affs_hash_name(struct super_block *sb, const u8 *name, unsigned int len)
159 toupper_t toupper = affs_get_toupper(sb);
162 hash = len = min(len, AFFSNAMEMAX);
163 for (; len > 0; len--)
164 hash = (hash * 13 + toupper(*name++)) & 0x7ff;
166 return hash % AFFS_SB(sb)->s_hashsize;
169 static struct buffer_head *
170 affs_find_entry(struct inode *dir, struct dentry *dentry)
172 struct super_block *sb = dir->i_sb;
173 struct buffer_head *bh;
174 toupper_t toupper = affs_get_toupper(sb);
177 pr_debug("%s(\"%pd\")\n", __func__, dentry);
179 bh = affs_bread(sb, dir->i_ino);
181 return ERR_PTR(-EIO);
183 key = be32_to_cpu(AFFS_HEAD(bh)->table[affs_hash_name(sb, dentry->d_name.name, dentry->d_name.len)]);
189 bh = affs_bread(sb, key);
191 return ERR_PTR(-EIO);
192 if (affs_match(dentry, AFFS_TAIL(sb, bh)->name, toupper))
194 key = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
199 affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
201 struct super_block *sb = dir->i_sb;
202 struct buffer_head *bh;
203 struct inode *inode = NULL;
205 pr_debug("%s(\"%pd\")\n", __func__, dentry);
208 bh = affs_find_entry(dir, dentry);
210 affs_unlock_dir(dir);
214 u32 ino = bh->b_blocknr;
216 /* store the real header ino in d_fsdata for faster lookups */
217 dentry->d_fsdata = (void *)(long)ino;
218 switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
219 //link to dirs disabled
222 ino = be32_to_cpu(AFFS_TAIL(sb, bh)->original);
225 inode = affs_iget(sb, ino);
227 affs_unlock_dir(dir);
228 return ERR_CAST(inode);
231 d_add(dentry, inode);
232 affs_unlock_dir(dir);
237 affs_unlink(struct inode *dir, struct dentry *dentry)
239 pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino,
240 d_inode(dentry)->i_ino, dentry);
242 return affs_remove_header(dentry);
246 affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
248 struct super_block *sb = dir->i_sb;
252 pr_debug("%s(%lu,\"%pd\",0%ho)\n",
253 __func__, dir->i_ino, dentry, mode);
255 inode = affs_new_inode(dir);
259 inode->i_mode = mode;
260 affs_mode_to_prot(inode);
261 mark_inode_dirty(inode);
263 inode->i_op = &affs_file_inode_operations;
264 inode->i_fop = &affs_file_operations;
265 inode->i_mapping->a_ops = affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS) ?
266 &affs_aops_ofs : &affs_aops;
267 error = affs_add_entry(dir, inode, dentry, ST_FILE);
277 affs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
282 pr_debug("%s(%lu,\"%pd\",0%ho)\n",
283 __func__, dir->i_ino, dentry, mode);
285 inode = affs_new_inode(dir);
289 inode->i_mode = S_IFDIR | mode;
290 affs_mode_to_prot(inode);
292 inode->i_op = &affs_dir_inode_operations;
293 inode->i_fop = &affs_dir_operations;
295 error = affs_add_entry(dir, inode, dentry, ST_USERDIR);
298 mark_inode_dirty(inode);
306 affs_rmdir(struct inode *dir, struct dentry *dentry)
308 pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino,
309 d_inode(dentry)->i_ino, dentry);
311 return affs_remove_header(dentry);
315 affs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
317 struct super_block *sb = dir->i_sb;
318 struct buffer_head *bh;
321 int i, maxlen, error;
324 pr_debug("%s(%lu,\"%pd\" -> \"%s\")\n",
325 __func__, dir->i_ino, dentry, symname);
327 maxlen = AFFS_SB(sb)->s_hashsize * sizeof(u32) - 1;
328 inode = affs_new_inode(dir);
332 inode->i_op = &affs_symlink_inode_operations;
333 inode_nohighmem(inode);
334 inode->i_data.a_ops = &affs_symlink_aops;
335 inode->i_mode = S_IFLNK | 0777;
336 affs_mode_to_prot(inode);
339 bh = affs_bread(sb, inode->i_ino);
343 p = (char *)AFFS_HEAD(bh)->table;
345 if (*symname == '/') {
346 struct affs_sb_info *sbi = AFFS_SB(sb);
347 while (*symname == '/')
349 spin_lock(&sbi->symlink_lock);
350 while (sbi->s_volume[i]) /* Cannot overflow */
351 *p++ = sbi->s_volume[i++];
352 spin_unlock(&sbi->symlink_lock);
354 while (i < maxlen && (c = *symname++)) {
355 if (c == '.' && lc == '/' && *symname == '.' && symname[1] == '/') {
360 } else if (c == '.' && lc == '/' && *symname == '/') {
369 while (*symname == '/')
373 inode->i_size = i + 1;
374 mark_buffer_dirty_inode(bh, inode);
376 mark_inode_dirty(inode);
378 error = affs_add_entry(dir, inode, dentry, ST_SOFTLINK);
386 mark_inode_dirty(inode);
392 affs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
394 struct inode *inode = d_inode(old_dentry);
396 pr_debug("%s(%lu, %lu, \"%pd\")\n", __func__, inode->i_ino, dir->i_ino,
399 return affs_add_entry(dir, inode, dentry, ST_LINKFILE);
403 affs_rename(struct inode *old_dir, struct dentry *old_dentry,
404 struct inode *new_dir, struct dentry *new_dentry)
406 struct super_block *sb = old_dir->i_sb;
407 struct buffer_head *bh = NULL;
410 retval = affs_check_name(new_dentry->d_name.name,
411 new_dentry->d_name.len,
412 affs_nofilenametruncate(old_dentry));
417 /* Unlink destination if it already exists */
418 if (d_really_is_positive(new_dentry)) {
419 retval = affs_remove_header(new_dentry);
424 bh = affs_bread(sb, d_inode(old_dentry)->i_ino);
428 /* Remove header from its parent directory. */
429 affs_lock_dir(old_dir);
430 retval = affs_remove_hash(old_dir, bh);
431 affs_unlock_dir(old_dir);
435 /* And insert it into the new directory with the new name. */
436 affs_copy_name(AFFS_TAIL(sb, bh)->name, new_dentry);
437 affs_fix_checksum(sb, bh);
438 affs_lock_dir(new_dir);
439 retval = affs_insert_hash(new_dir, bh);
440 affs_unlock_dir(new_dir);
441 /* TODO: move it back to old_dir, if error? */
444 mark_buffer_dirty_inode(bh, retval ? old_dir : new_dir);
450 affs_xrename(struct inode *old_dir, struct dentry *old_dentry,
451 struct inode *new_dir, struct dentry *new_dentry)
454 struct super_block *sb = old_dir->i_sb;
455 struct buffer_head *bh_old = NULL;
456 struct buffer_head *bh_new = NULL;
459 bh_old = affs_bread(sb, d_inode(old_dentry)->i_ino);
463 bh_new = affs_bread(sb, d_inode(new_dentry)->i_ino);
469 /* Remove old header from its parent directory. */
470 affs_lock_dir(old_dir);
471 retval = affs_remove_hash(old_dir, bh_old);
472 affs_unlock_dir(old_dir);
476 /* Remove new header from its parent directory. */
477 affs_lock_dir(new_dir);
478 retval = affs_remove_hash(new_dir, bh_new);
479 affs_unlock_dir(new_dir);
483 /* Insert old into the new directory with the new name. */
484 affs_copy_name(AFFS_TAIL(sb, bh_old)->name, new_dentry);
485 affs_fix_checksum(sb, bh_old);
486 affs_lock_dir(new_dir);
487 retval = affs_insert_hash(new_dir, bh_old);
488 affs_unlock_dir(new_dir);
490 /* Insert new into the old directory with the old name. */
491 affs_copy_name(AFFS_TAIL(sb, bh_new)->name, old_dentry);
492 affs_fix_checksum(sb, bh_new);
493 affs_lock_dir(old_dir);
494 retval = affs_insert_hash(old_dir, bh_new);
495 affs_unlock_dir(old_dir);
497 mark_buffer_dirty_inode(bh_old, new_dir);
498 mark_buffer_dirty_inode(bh_new, old_dir);
504 int affs_rename2(struct inode *old_dir, struct dentry *old_dentry,
505 struct inode *new_dir, struct dentry *new_dentry,
509 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
512 pr_debug("%s(old=%lu,\"%pd\" to new=%lu,\"%pd\")\n", __func__,
513 old_dir->i_ino, old_dentry, new_dir->i_ino, new_dentry);
515 if (flags & RENAME_EXCHANGE)
516 return affs_xrename(old_dir, old_dentry, new_dir, new_dentry);
518 return affs_rename(old_dir, old_dentry, new_dir, new_dentry);
521 static struct dentry *affs_get_parent(struct dentry *child)
523 struct inode *parent;
524 struct buffer_head *bh;
526 bh = affs_bread(child->d_sb, d_inode(child)->i_ino);
528 return ERR_PTR(-EIO);
530 parent = affs_iget(child->d_sb,
531 be32_to_cpu(AFFS_TAIL(child->d_sb, bh)->parent));
534 return ERR_CAST(parent);
536 return d_obtain_alias(parent);
539 static struct inode *affs_nfs_get_inode(struct super_block *sb, u64 ino,
544 if (!affs_validblock(sb, ino))
545 return ERR_PTR(-ESTALE);
547 inode = affs_iget(sb, ino);
549 return ERR_CAST(inode);
554 static struct dentry *affs_fh_to_dentry(struct super_block *sb, struct fid *fid,
555 int fh_len, int fh_type)
557 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
561 static struct dentry *affs_fh_to_parent(struct super_block *sb, struct fid *fid,
562 int fh_len, int fh_type)
564 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
568 const struct export_operations affs_export_ops = {
569 .fh_to_dentry = affs_fh_to_dentry,
570 .fh_to_parent = affs_fh_to_parent,
571 .get_parent = affs_get_parent,
574 const struct dentry_operations affs_dentry_operations = {
575 .d_hash = affs_hash_dentry,
576 .d_compare = affs_compare_dentry,
579 const struct dentry_operations affs_intl_dentry_operations = {
580 .d_hash = affs_intl_hash_dentry,
581 .d_compare = affs_intl_compare_dentry,