WIP FPC-III support
[linux/fpc-iii.git] / fs / exfat / namei.c
blob2932b23a3b6c36ebfb82e5a5e7621c07fbb2822d
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
4 */
6 #include <linux/iversion.h>
7 #include <linux/namei.h>
8 #include <linux/slab.h>
9 #include <linux/buffer_head.h>
10 #include <linux/nls.h>
12 #include "exfat_raw.h"
13 #include "exfat_fs.h"
15 static inline unsigned long exfat_d_version(struct dentry *dentry)
17 return (unsigned long) dentry->d_fsdata;
20 static inline void exfat_d_version_set(struct dentry *dentry,
21 unsigned long version)
23 dentry->d_fsdata = (void *) version;
27 * If new entry was created in the parent, it could create the 8.3 alias (the
28 * shortname of logname). So, the parent may have the negative-dentry which
29 * matches the created 8.3 alias.
31 * If it happened, the negative dentry isn't actually negative anymore. So,
32 * drop it.
34 static int exfat_d_revalidate(struct dentry *dentry, unsigned int flags)
36 int ret;
38 if (flags & LOOKUP_RCU)
39 return -ECHILD;
42 * This is not negative dentry. Always valid.
44 * Note, rename() to existing directory entry will have ->d_inode, and
45 * will use existing name which isn't specified name by user.
47 * We may be able to drop this positive dentry here. But dropping
48 * positive dentry isn't good idea. So it's unsupported like
49 * rename("filename", "FILENAME") for now.
51 if (d_really_is_positive(dentry))
52 return 1;
55 * Drop the negative dentry, in order to make sure to use the case
56 * sensitive name which is specified by user if this is for creation.
58 if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
59 return 0;
61 spin_lock(&dentry->d_lock);
62 ret = inode_eq_iversion(d_inode(dentry->d_parent),
63 exfat_d_version(dentry));
64 spin_unlock(&dentry->d_lock);
65 return ret;
68 /* returns the length of a struct qstr, ignoring trailing dots */
69 static unsigned int exfat_striptail_len(unsigned int len, const char *name)
71 while (len && name[len - 1] == '.')
72 len--;
73 return len;
77 * Compute the hash for the exfat name corresponding to the dentry. If the name
78 * is invalid, we leave the hash code unchanged so that the existing dentry can
79 * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate.
81 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
83 struct super_block *sb = dentry->d_sb;
84 struct nls_table *t = EXFAT_SB(sb)->nls_io;
85 const unsigned char *name = qstr->name;
86 unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
87 unsigned long hash = init_name_hash(dentry);
88 int i, charlen;
89 wchar_t c;
91 for (i = 0; i < len; i += charlen) {
92 charlen = t->char2uni(&name[i], len - i, &c);
93 if (charlen < 0)
94 return charlen;
95 hash = partial_name_hash(exfat_toupper(sb, c), hash);
98 qstr->hash = end_name_hash(hash);
99 return 0;
102 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
103 const char *str, const struct qstr *name)
105 struct super_block *sb = dentry->d_sb;
106 struct nls_table *t = EXFAT_SB(sb)->nls_io;
107 unsigned int alen = exfat_striptail_len(name->len, name->name);
108 unsigned int blen = exfat_striptail_len(len, str);
109 wchar_t c1, c2;
110 int charlen, i;
112 if (alen != blen)
113 return 1;
115 for (i = 0; i < len; i += charlen) {
116 charlen = t->char2uni(&name->name[i], alen - i, &c1);
117 if (charlen < 0)
118 return 1;
119 if (charlen != t->char2uni(&str[i], blen - i, &c2))
120 return 1;
122 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
123 return 1;
126 return 0;
129 const struct dentry_operations exfat_dentry_ops = {
130 .d_revalidate = exfat_d_revalidate,
131 .d_hash = exfat_d_hash,
132 .d_compare = exfat_d_cmp,
135 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
137 struct super_block *sb = dentry->d_sb;
138 const unsigned char *name = qstr->name;
139 unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
140 unsigned long hash = init_name_hash(dentry);
141 int i, charlen;
142 unicode_t u;
144 for (i = 0; i < len; i += charlen) {
145 charlen = utf8_to_utf32(&name[i], len - i, &u);
146 if (charlen < 0)
147 return charlen;
150 * exfat_toupper() works only for code points up to the U+FFFF.
152 hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u,
153 hash);
156 qstr->hash = end_name_hash(hash);
157 return 0;
160 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
161 const char *str, const struct qstr *name)
163 struct super_block *sb = dentry->d_sb;
164 unsigned int alen = exfat_striptail_len(name->len, name->name);
165 unsigned int blen = exfat_striptail_len(len, str);
166 unicode_t u_a, u_b;
167 int charlen, i;
169 if (alen != blen)
170 return 1;
172 for (i = 0; i < alen; i += charlen) {
173 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
174 if (charlen < 0)
175 return 1;
176 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
177 return 1;
179 if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
180 if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
181 return 1;
182 } else {
183 if (u_a != u_b)
184 return 1;
188 return 0;
191 const struct dentry_operations exfat_utf8_dentry_ops = {
192 .d_revalidate = exfat_d_revalidate,
193 .d_hash = exfat_utf8_d_hash,
194 .d_compare = exfat_utf8_d_cmp,
197 /* used only in search empty_slot() */
198 #define CNT_UNUSED_NOHIT (-1)
199 #define CNT_UNUSED_HIT (-2)
200 /* search EMPTY CONTINUOUS "num_entries" entries */
201 static int exfat_search_empty_slot(struct super_block *sb,
202 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
203 int num_entries)
205 int i, dentry, num_empty = 0;
206 int dentries_per_clu;
207 unsigned int type;
208 struct exfat_chain clu;
209 struct exfat_dentry *ep;
210 struct exfat_sb_info *sbi = EXFAT_SB(sb);
211 struct buffer_head *bh;
213 dentries_per_clu = sbi->dentries_per_clu;
215 if (hint_femp->eidx != EXFAT_HINT_NONE) {
216 dentry = hint_femp->eidx;
217 if (num_entries <= hint_femp->count) {
218 hint_femp->eidx = EXFAT_HINT_NONE;
219 return dentry;
222 exfat_chain_dup(&clu, &hint_femp->cur);
223 } else {
224 exfat_chain_dup(&clu, p_dir);
225 dentry = 0;
228 while (clu.dir != EXFAT_EOF_CLUSTER) {
229 i = dentry & (dentries_per_clu - 1);
231 for (; i < dentries_per_clu; i++, dentry++) {
232 ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
233 if (!ep)
234 return -EIO;
235 type = exfat_get_entry_type(ep);
236 brelse(bh);
238 if (type == TYPE_UNUSED || type == TYPE_DELETED) {
239 num_empty++;
240 if (hint_femp->eidx == EXFAT_HINT_NONE) {
241 hint_femp->eidx = dentry;
242 hint_femp->count = CNT_UNUSED_NOHIT;
243 exfat_chain_set(&hint_femp->cur,
244 clu.dir, clu.size, clu.flags);
247 if (type == TYPE_UNUSED &&
248 hint_femp->count != CNT_UNUSED_HIT)
249 hint_femp->count = CNT_UNUSED_HIT;
250 } else {
251 if (hint_femp->eidx != EXFAT_HINT_NONE &&
252 hint_femp->count == CNT_UNUSED_HIT) {
253 /* unused empty group means
254 * an empty group which includes
255 * unused dentry
257 exfat_fs_error(sb,
258 "found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)",
259 dentry, hint_femp->eidx,
260 p_dir->dir, clu.dir);
261 return -EIO;
264 num_empty = 0;
265 hint_femp->eidx = EXFAT_HINT_NONE;
268 if (num_empty >= num_entries) {
269 /* found and invalidate hint_femp */
270 hint_femp->eidx = EXFAT_HINT_NONE;
271 return (dentry - (num_entries - 1));
275 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
276 if (--clu.size > 0)
277 clu.dir++;
278 else
279 clu.dir = EXFAT_EOF_CLUSTER;
280 } else {
281 if (exfat_get_next_cluster(sb, &clu.dir))
282 return -EIO;
286 return -ENOSPC;
289 static int exfat_check_max_dentries(struct inode *inode)
291 if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
293 * exFAT spec allows a dir to grow up to 8388608(256MB)
294 * dentries
296 return -ENOSPC;
298 return 0;
301 /* find empty directory entry.
302 * if there isn't any empty slot, expand cluster chain.
304 static int exfat_find_empty_entry(struct inode *inode,
305 struct exfat_chain *p_dir, int num_entries)
307 int dentry;
308 unsigned int ret, last_clu;
309 sector_t sector;
310 loff_t size = 0;
311 struct exfat_chain clu;
312 struct exfat_dentry *ep = NULL;
313 struct super_block *sb = inode->i_sb;
314 struct exfat_sb_info *sbi = EXFAT_SB(sb);
315 struct exfat_inode_info *ei = EXFAT_I(inode);
316 struct exfat_hint_femp hint_femp;
318 hint_femp.eidx = EXFAT_HINT_NONE;
320 if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
321 hint_femp = ei->hint_femp;
322 ei->hint_femp.eidx = EXFAT_HINT_NONE;
325 while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
326 num_entries)) < 0) {
327 if (dentry == -EIO)
328 break;
330 if (exfat_check_max_dentries(inode))
331 return -ENOSPC;
333 /* we trust p_dir->size regardless of FAT type */
334 if (exfat_find_last_cluster(sb, p_dir, &last_clu))
335 return -EIO;
338 * Allocate new cluster to this directory
340 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
342 /* allocate a cluster */
343 ret = exfat_alloc_cluster(inode, 1, &clu);
344 if (ret)
345 return ret;
347 if (exfat_zeroed_cluster(inode, clu.dir))
348 return -EIO;
350 /* append to the FAT chain */
351 if (clu.flags != p_dir->flags) {
352 /* no-fat-chain bit is disabled,
353 * so fat-chain should be synced with alloc-bitmap
355 exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
356 p_dir->flags = ALLOC_FAT_CHAIN;
357 hint_femp.cur.flags = ALLOC_FAT_CHAIN;
360 if (clu.flags == ALLOC_FAT_CHAIN)
361 if (exfat_ent_set(sb, last_clu, clu.dir))
362 return -EIO;
364 if (hint_femp.eidx == EXFAT_HINT_NONE) {
365 /* the special case that new dentry
366 * should be allocated from the start of new cluster
368 hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi);
369 hint_femp.count = sbi->dentries_per_clu;
371 exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
373 hint_femp.cur.size++;
374 p_dir->size++;
375 size = EXFAT_CLU_TO_B(p_dir->size, sbi);
377 /* update the directory entry */
378 if (p_dir->dir != sbi->root_dir) {
379 struct buffer_head *bh;
381 ep = exfat_get_dentry(sb,
382 &(ei->dir), ei->entry + 1, &bh, &sector);
383 if (!ep)
384 return -EIO;
386 ep->dentry.stream.valid_size = cpu_to_le64(size);
387 ep->dentry.stream.size = ep->dentry.stream.valid_size;
388 ep->dentry.stream.flags = p_dir->flags;
389 exfat_update_bh(bh, IS_DIRSYNC(inode));
390 brelse(bh);
391 if (exfat_update_dir_chksum(inode, &(ei->dir),
392 ei->entry))
393 return -EIO;
396 /* directory inode should be updated in here */
397 i_size_write(inode, size);
398 EXFAT_I(inode)->i_size_ondisk += sbi->cluster_size;
399 EXFAT_I(inode)->i_size_aligned += sbi->cluster_size;
400 EXFAT_I(inode)->flags = p_dir->flags;
401 inode->i_blocks += 1 << sbi->sect_per_clus_bits;
404 return dentry;
408 * Name Resolution Functions :
409 * Zero if it was successful; otherwise nonzero.
411 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
412 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
413 int lookup)
415 int namelen;
416 int lossy = NLS_NAME_NO_LOSSY;
417 struct super_block *sb = inode->i_sb;
418 struct exfat_sb_info *sbi = EXFAT_SB(sb);
419 struct exfat_inode_info *ei = EXFAT_I(inode);
421 /* strip all trailing periods */
422 namelen = exfat_striptail_len(strlen(path), path);
423 if (!namelen)
424 return -ENOENT;
426 if (strlen(path) > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
427 return -ENAMETOOLONG;
430 * strip all leading spaces :
431 * "MS windows 7" supports leading spaces.
432 * So we should skip this preprocessing for compatibility.
435 /* file name conversion :
436 * If lookup case, we allow bad-name for compatibility.
438 namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
439 &lossy);
440 if (namelen < 0)
441 return namelen; /* return error value */
443 if ((lossy && !lookup) || !namelen)
444 return -EINVAL;
446 exfat_chain_set(p_dir, ei->start_clu,
447 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
449 return 0;
452 static inline int exfat_resolve_path(struct inode *inode,
453 const unsigned char *path, struct exfat_chain *dir,
454 struct exfat_uni_name *uni)
456 return __exfat_resolve_path(inode, path, dir, uni, 0);
459 static inline int exfat_resolve_path_for_lookup(struct inode *inode,
460 const unsigned char *path, struct exfat_chain *dir,
461 struct exfat_uni_name *uni)
463 return __exfat_resolve_path(inode, path, dir, uni, 1);
466 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
468 return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
471 static int exfat_add_entry(struct inode *inode, const char *path,
472 struct exfat_chain *p_dir, unsigned int type,
473 struct exfat_dir_entry *info)
475 int ret, dentry, num_entries;
476 struct super_block *sb = inode->i_sb;
477 struct exfat_sb_info *sbi = EXFAT_SB(sb);
478 struct exfat_uni_name uniname;
479 struct exfat_chain clu;
480 int clu_size = 0;
481 unsigned int start_clu = EXFAT_FREE_CLUSTER;
483 ret = exfat_resolve_path(inode, path, p_dir, &uniname);
484 if (ret)
485 goto out;
487 num_entries = exfat_calc_num_entries(&uniname);
488 if (num_entries < 0) {
489 ret = num_entries;
490 goto out;
493 /* exfat_find_empty_entry must be called before alloc_cluster() */
494 dentry = exfat_find_empty_entry(inode, p_dir, num_entries);
495 if (dentry < 0) {
496 ret = dentry; /* -EIO or -ENOSPC */
497 goto out;
500 if (type == TYPE_DIR) {
501 ret = exfat_alloc_new_dir(inode, &clu);
502 if (ret)
503 goto out;
504 start_clu = clu.dir;
505 clu_size = sbi->cluster_size;
508 /* update the directory entry */
509 /* fill the dos name directory entry information of the created file.
510 * the first cluster is not determined yet. (0)
512 ret = exfat_init_dir_entry(inode, p_dir, dentry, type,
513 start_clu, clu_size);
514 if (ret)
515 goto out;
517 ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname);
518 if (ret)
519 goto out;
521 info->dir = *p_dir;
522 info->entry = dentry;
523 info->flags = ALLOC_NO_FAT_CHAIN;
524 info->type = type;
526 if (type == TYPE_FILE) {
527 info->attr = ATTR_ARCHIVE;
528 info->start_clu = EXFAT_EOF_CLUSTER;
529 info->size = 0;
530 info->num_subdirs = 0;
531 } else {
532 info->attr = ATTR_SUBDIR;
533 info->start_clu = start_clu;
534 info->size = clu_size;
535 info->num_subdirs = EXFAT_MIN_SUBDIR;
537 memset(&info->crtime, 0, sizeof(info->crtime));
538 memset(&info->mtime, 0, sizeof(info->mtime));
539 memset(&info->atime, 0, sizeof(info->atime));
540 out:
541 return ret;
544 static int exfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
545 bool excl)
547 struct super_block *sb = dir->i_sb;
548 struct inode *inode;
549 struct exfat_chain cdir;
550 struct exfat_dir_entry info;
551 loff_t i_pos;
552 int err;
554 mutex_lock(&EXFAT_SB(sb)->s_lock);
555 exfat_set_volume_dirty(sb);
556 err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,
557 &info);
558 exfat_clear_volume_dirty(sb);
559 if (err)
560 goto unlock;
562 inode_inc_iversion(dir);
563 dir->i_ctime = dir->i_mtime = current_time(dir);
564 if (IS_DIRSYNC(dir))
565 exfat_sync_inode(dir);
566 else
567 mark_inode_dirty(dir);
569 i_pos = exfat_make_i_pos(&info);
570 inode = exfat_build_inode(sb, &info, i_pos);
571 err = PTR_ERR_OR_ZERO(inode);
572 if (err)
573 goto unlock;
575 inode_inc_iversion(inode);
576 inode->i_mtime = inode->i_atime = inode->i_ctime =
577 EXFAT_I(inode)->i_crtime = current_time(inode);
578 exfat_truncate_atime(&inode->i_atime);
579 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
581 d_instantiate(dentry, inode);
582 unlock:
583 mutex_unlock(&EXFAT_SB(sb)->s_lock);
584 return err;
587 /* lookup a file */
588 static int exfat_find(struct inode *dir, struct qstr *qname,
589 struct exfat_dir_entry *info)
591 int ret, dentry, num_entries, count;
592 struct exfat_chain cdir;
593 struct exfat_uni_name uni_name;
594 struct super_block *sb = dir->i_sb;
595 struct exfat_sb_info *sbi = EXFAT_SB(sb);
596 struct exfat_inode_info *ei = EXFAT_I(dir);
597 struct exfat_dentry *ep, *ep2;
598 struct exfat_entry_set_cache *es;
600 if (qname->len == 0)
601 return -ENOENT;
603 /* check the validity of directory name in the given pathname */
604 ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name);
605 if (ret)
606 return ret;
608 num_entries = exfat_calc_num_entries(&uni_name);
609 if (num_entries < 0)
610 return num_entries;
612 /* check the validation of hint_stat and initialize it if required */
613 if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
614 ei->hint_stat.clu = cdir.dir;
615 ei->hint_stat.eidx = 0;
616 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
617 ei->hint_femp.eidx = EXFAT_HINT_NONE;
620 /* search the file name for directories */
621 dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name,
622 num_entries, TYPE_ALL);
624 if (dentry < 0)
625 return dentry; /* -error value */
627 info->dir = cdir;
628 info->entry = dentry;
629 info->num_subdirs = 0;
631 es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES);
632 if (!es)
633 return -EIO;
634 ep = exfat_get_dentry_cached(es, 0);
635 ep2 = exfat_get_dentry_cached(es, 1);
637 info->type = exfat_get_entry_type(ep);
638 info->attr = le16_to_cpu(ep->dentry.file.attr);
639 info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
640 if ((info->type == TYPE_FILE) && (info->size == 0)) {
641 info->flags = ALLOC_NO_FAT_CHAIN;
642 info->start_clu = EXFAT_EOF_CLUSTER;
643 } else {
644 info->flags = ep2->dentry.stream.flags;
645 info->start_clu =
646 le32_to_cpu(ep2->dentry.stream.start_clu);
649 exfat_get_entry_time(sbi, &info->crtime,
650 ep->dentry.file.create_tz,
651 ep->dentry.file.create_time,
652 ep->dentry.file.create_date,
653 ep->dentry.file.create_time_cs);
654 exfat_get_entry_time(sbi, &info->mtime,
655 ep->dentry.file.modify_tz,
656 ep->dentry.file.modify_time,
657 ep->dentry.file.modify_date,
658 ep->dentry.file.modify_time_cs);
659 exfat_get_entry_time(sbi, &info->atime,
660 ep->dentry.file.access_tz,
661 ep->dentry.file.access_time,
662 ep->dentry.file.access_date,
664 exfat_free_dentry_set(es, false);
666 if (ei->start_clu == EXFAT_FREE_CLUSTER) {
667 exfat_fs_error(sb,
668 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
669 i_size_read(dir), ei->dir.dir, ei->entry);
670 return -EIO;
673 if (info->type == TYPE_DIR) {
674 exfat_chain_set(&cdir, info->start_clu,
675 EXFAT_B_TO_CLU(info->size, sbi), info->flags);
676 count = exfat_count_dir_entries(sb, &cdir);
677 if (count < 0)
678 return -EIO;
680 info->num_subdirs = count + EXFAT_MIN_SUBDIR;
682 return 0;
685 static int exfat_d_anon_disconn(struct dentry *dentry)
687 return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
690 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
691 unsigned int flags)
693 struct super_block *sb = dir->i_sb;
694 struct inode *inode;
695 struct dentry *alias;
696 struct exfat_dir_entry info;
697 int err;
698 loff_t i_pos;
699 mode_t i_mode;
701 mutex_lock(&EXFAT_SB(sb)->s_lock);
702 err = exfat_find(dir, &dentry->d_name, &info);
703 if (err) {
704 if (err == -ENOENT) {
705 inode = NULL;
706 goto out;
708 goto unlock;
711 i_pos = exfat_make_i_pos(&info);
712 inode = exfat_build_inode(sb, &info, i_pos);
713 err = PTR_ERR_OR_ZERO(inode);
714 if (err)
715 goto unlock;
717 i_mode = inode->i_mode;
718 alias = d_find_alias(inode);
721 * Checking "alias->d_parent == dentry->d_parent" to make sure
722 * FS is not corrupted (especially double linked dir).
724 if (alias && alias->d_parent == dentry->d_parent &&
725 !exfat_d_anon_disconn(alias)) {
728 * Unhashed alias is able to exist because of revalidate()
729 * called by lookup_fast. You can easily make this status
730 * by calling create and lookup concurrently
731 * In such case, we reuse an alias instead of new dentry
733 if (d_unhashed(alias)) {
734 WARN_ON(alias->d_name.hash_len !=
735 dentry->d_name.hash_len);
736 exfat_info(sb, "rehashed a dentry(%p) in read lookup",
737 alias);
738 d_drop(dentry);
739 d_rehash(alias);
740 } else if (!S_ISDIR(i_mode)) {
742 * This inode has non anonymous-DCACHE_DISCONNECTED
743 * dentry. This means, the user did ->lookup() by an
744 * another name (longname vs 8.3 alias of it) in past.
746 * Switch to new one for reason of locality if possible.
748 d_move(alias, dentry);
750 iput(inode);
751 mutex_unlock(&EXFAT_SB(sb)->s_lock);
752 return alias;
754 dput(alias);
755 out:
756 mutex_unlock(&EXFAT_SB(sb)->s_lock);
757 if (!inode)
758 exfat_d_version_set(dentry, inode_query_iversion(dir));
760 return d_splice_alias(inode, dentry);
761 unlock:
762 mutex_unlock(&EXFAT_SB(sb)->s_lock);
763 return ERR_PTR(err);
766 /* remove an entry, BUT don't truncate */
767 static int exfat_unlink(struct inode *dir, struct dentry *dentry)
769 struct exfat_chain cdir;
770 struct exfat_dentry *ep;
771 struct super_block *sb = dir->i_sb;
772 struct inode *inode = dentry->d_inode;
773 struct exfat_inode_info *ei = EXFAT_I(inode);
774 struct buffer_head *bh;
775 sector_t sector;
776 int num_entries, entry, err = 0;
778 mutex_lock(&EXFAT_SB(sb)->s_lock);
779 exfat_chain_dup(&cdir, &ei->dir);
780 entry = ei->entry;
781 if (ei->dir.dir == DIR_DELETED) {
782 exfat_err(sb, "abnormal access to deleted dentry");
783 err = -ENOENT;
784 goto unlock;
787 ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
788 if (!ep) {
789 err = -EIO;
790 goto unlock;
792 num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
793 if (num_entries < 0) {
794 err = -EIO;
795 brelse(bh);
796 goto unlock;
798 num_entries++;
799 brelse(bh);
801 exfat_set_volume_dirty(sb);
802 /* update the directory entry */
803 if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) {
804 err = -EIO;
805 goto unlock;
808 /* This doesn't modify ei */
809 ei->dir.dir = DIR_DELETED;
810 exfat_clear_volume_dirty(sb);
812 inode_inc_iversion(dir);
813 dir->i_mtime = dir->i_atime = current_time(dir);
814 exfat_truncate_atime(&dir->i_atime);
815 if (IS_DIRSYNC(dir))
816 exfat_sync_inode(dir);
817 else
818 mark_inode_dirty(dir);
820 clear_nlink(inode);
821 inode->i_mtime = inode->i_atime = current_time(inode);
822 exfat_truncate_atime(&inode->i_atime);
823 exfat_unhash_inode(inode);
824 exfat_d_version_set(dentry, inode_query_iversion(dir));
825 unlock:
826 mutex_unlock(&EXFAT_SB(sb)->s_lock);
827 return err;
830 static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
832 struct super_block *sb = dir->i_sb;
833 struct inode *inode;
834 struct exfat_dir_entry info;
835 struct exfat_chain cdir;
836 loff_t i_pos;
837 int err;
839 mutex_lock(&EXFAT_SB(sb)->s_lock);
840 exfat_set_volume_dirty(sb);
841 err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
842 &info);
843 exfat_clear_volume_dirty(sb);
844 if (err)
845 goto unlock;
847 inode_inc_iversion(dir);
848 dir->i_ctime = dir->i_mtime = current_time(dir);
849 if (IS_DIRSYNC(dir))
850 exfat_sync_inode(dir);
851 else
852 mark_inode_dirty(dir);
853 inc_nlink(dir);
855 i_pos = exfat_make_i_pos(&info);
856 inode = exfat_build_inode(sb, &info, i_pos);
857 err = PTR_ERR_OR_ZERO(inode);
858 if (err)
859 goto unlock;
861 inode_inc_iversion(inode);
862 inode->i_mtime = inode->i_atime = inode->i_ctime =
863 EXFAT_I(inode)->i_crtime = current_time(inode);
864 exfat_truncate_atime(&inode->i_atime);
865 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
867 d_instantiate(dentry, inode);
869 unlock:
870 mutex_unlock(&EXFAT_SB(sb)->s_lock);
871 return err;
874 static int exfat_check_dir_empty(struct super_block *sb,
875 struct exfat_chain *p_dir)
877 int i, dentries_per_clu;
878 unsigned int type;
879 struct exfat_chain clu;
880 struct exfat_dentry *ep;
881 struct exfat_sb_info *sbi = EXFAT_SB(sb);
882 struct buffer_head *bh;
884 dentries_per_clu = sbi->dentries_per_clu;
886 exfat_chain_dup(&clu, p_dir);
888 while (clu.dir != EXFAT_EOF_CLUSTER) {
889 for (i = 0; i < dentries_per_clu; i++) {
890 ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
891 if (!ep)
892 return -EIO;
893 type = exfat_get_entry_type(ep);
894 brelse(bh);
895 if (type == TYPE_UNUSED)
896 return 0;
898 if (type != TYPE_FILE && type != TYPE_DIR)
899 continue;
901 return -ENOTEMPTY;
904 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
905 if (--clu.size > 0)
906 clu.dir++;
907 else
908 clu.dir = EXFAT_EOF_CLUSTER;
909 } else {
910 if (exfat_get_next_cluster(sb, &(clu.dir)))
911 return -EIO;
915 return 0;
918 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
920 struct inode *inode = dentry->d_inode;
921 struct exfat_dentry *ep;
922 struct exfat_chain cdir, clu_to_free;
923 struct super_block *sb = inode->i_sb;
924 struct exfat_sb_info *sbi = EXFAT_SB(sb);
925 struct exfat_inode_info *ei = EXFAT_I(inode);
926 struct buffer_head *bh;
927 sector_t sector;
928 int num_entries, entry, err;
930 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
932 exfat_chain_dup(&cdir, &ei->dir);
933 entry = ei->entry;
935 if (ei->dir.dir == DIR_DELETED) {
936 exfat_err(sb, "abnormal access to deleted dentry");
937 err = -ENOENT;
938 goto unlock;
941 exfat_chain_set(&clu_to_free, ei->start_clu,
942 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
944 err = exfat_check_dir_empty(sb, &clu_to_free);
945 if (err) {
946 if (err == -EIO)
947 exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)",
948 err);
949 goto unlock;
952 ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
953 if (!ep) {
954 err = -EIO;
955 goto unlock;
958 num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
959 if (num_entries < 0) {
960 err = -EIO;
961 brelse(bh);
962 goto unlock;
964 num_entries++;
965 brelse(bh);
967 exfat_set_volume_dirty(sb);
968 err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries);
969 if (err) {
970 exfat_err(sb, "failed to exfat_remove_entries : err(%d)", err);
971 goto unlock;
973 ei->dir.dir = DIR_DELETED;
974 exfat_clear_volume_dirty(sb);
976 inode_inc_iversion(dir);
977 dir->i_mtime = dir->i_atime = current_time(dir);
978 exfat_truncate_atime(&dir->i_atime);
979 if (IS_DIRSYNC(dir))
980 exfat_sync_inode(dir);
981 else
982 mark_inode_dirty(dir);
983 drop_nlink(dir);
985 clear_nlink(inode);
986 inode->i_mtime = inode->i_atime = current_time(inode);
987 exfat_truncate_atime(&inode->i_atime);
988 exfat_unhash_inode(inode);
989 exfat_d_version_set(dentry, inode_query_iversion(dir));
990 unlock:
991 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
992 return err;
995 static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
996 int oldentry, struct exfat_uni_name *p_uniname,
997 struct exfat_inode_info *ei)
999 int ret, num_old_entries, num_new_entries;
1000 sector_t sector_old, sector_new;
1001 struct exfat_dentry *epold, *epnew;
1002 struct super_block *sb = inode->i_sb;
1003 struct buffer_head *new_bh, *old_bh;
1004 int sync = IS_DIRSYNC(inode);
1006 epold = exfat_get_dentry(sb, p_dir, oldentry, &old_bh, &sector_old);
1007 if (!epold)
1008 return -EIO;
1010 num_old_entries = exfat_count_ext_entries(sb, p_dir, oldentry, epold);
1011 if (num_old_entries < 0)
1012 return -EIO;
1013 num_old_entries++;
1015 num_new_entries = exfat_calc_num_entries(p_uniname);
1016 if (num_new_entries < 0)
1017 return num_new_entries;
1019 if (num_old_entries < num_new_entries) {
1020 int newentry;
1022 newentry =
1023 exfat_find_empty_entry(inode, p_dir, num_new_entries);
1024 if (newentry < 0)
1025 return newentry; /* -EIO or -ENOSPC */
1027 epnew = exfat_get_dentry(sb, p_dir, newentry, &new_bh,
1028 &sector_new);
1029 if (!epnew)
1030 return -EIO;
1032 *epnew = *epold;
1033 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1034 epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1035 ei->attr |= ATTR_ARCHIVE;
1037 exfat_update_bh(new_bh, sync);
1038 brelse(old_bh);
1039 brelse(new_bh);
1041 epold = exfat_get_dentry(sb, p_dir, oldentry + 1, &old_bh,
1042 &sector_old);
1043 if (!epold)
1044 return -EIO;
1045 epnew = exfat_get_dentry(sb, p_dir, newentry + 1, &new_bh,
1046 &sector_new);
1047 if (!epnew) {
1048 brelse(old_bh);
1049 return -EIO;
1052 *epnew = *epold;
1053 exfat_update_bh(new_bh, sync);
1054 brelse(old_bh);
1055 brelse(new_bh);
1057 ret = exfat_init_ext_entry(inode, p_dir, newentry,
1058 num_new_entries, p_uniname);
1059 if (ret)
1060 return ret;
1062 exfat_remove_entries(inode, p_dir, oldentry, 0,
1063 num_old_entries);
1064 ei->entry = newentry;
1065 } else {
1066 if (exfat_get_entry_type(epold) == TYPE_FILE) {
1067 epold->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1068 ei->attr |= ATTR_ARCHIVE;
1070 exfat_update_bh(old_bh, sync);
1071 brelse(old_bh);
1072 ret = exfat_init_ext_entry(inode, p_dir, oldentry,
1073 num_new_entries, p_uniname);
1074 if (ret)
1075 return ret;
1077 exfat_remove_entries(inode, p_dir, oldentry, num_new_entries,
1078 num_old_entries);
1080 return 0;
1083 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
1084 int oldentry, struct exfat_chain *p_newdir,
1085 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1087 int ret, newentry, num_new_entries, num_old_entries;
1088 sector_t sector_mov, sector_new;
1089 struct exfat_dentry *epmov, *epnew;
1090 struct super_block *sb = inode->i_sb;
1091 struct buffer_head *mov_bh, *new_bh;
1093 epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh, &sector_mov);
1094 if (!epmov)
1095 return -EIO;
1097 num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry,
1098 epmov);
1099 if (num_old_entries < 0)
1100 return -EIO;
1101 num_old_entries++;
1103 num_new_entries = exfat_calc_num_entries(p_uniname);
1104 if (num_new_entries < 0)
1105 return num_new_entries;
1107 newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries);
1108 if (newentry < 0)
1109 return newentry; /* -EIO or -ENOSPC */
1111 epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh, &sector_new);
1112 if (!epnew)
1113 return -EIO;
1115 *epnew = *epmov;
1116 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1117 epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1118 ei->attr |= ATTR_ARCHIVE;
1120 exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1121 brelse(mov_bh);
1122 brelse(new_bh);
1124 epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh,
1125 &sector_mov);
1126 if (!epmov)
1127 return -EIO;
1128 epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh,
1129 &sector_new);
1130 if (!epnew) {
1131 brelse(mov_bh);
1132 return -EIO;
1135 *epnew = *epmov;
1136 exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1137 brelse(mov_bh);
1138 brelse(new_bh);
1140 ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries,
1141 p_uniname);
1142 if (ret)
1143 return ret;
1145 exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries);
1147 exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1148 p_newdir->flags);
1150 ei->entry = newentry;
1151 return 0;
1154 static void exfat_update_parent_info(struct exfat_inode_info *ei,
1155 struct inode *parent_inode)
1157 struct exfat_sb_info *sbi = EXFAT_SB(parent_inode->i_sb);
1158 struct exfat_inode_info *parent_ei = EXFAT_I(parent_inode);
1159 loff_t parent_isize = i_size_read(parent_inode);
1162 * the problem that struct exfat_inode_info caches wrong parent info.
1164 * because of flag-mismatch of ei->dir,
1165 * there is abnormal traversing cluster chain.
1167 if (unlikely(parent_ei->flags != ei->dir.flags ||
1168 parent_isize != EXFAT_CLU_TO_B(ei->dir.size, sbi) ||
1169 parent_ei->start_clu != ei->dir.dir)) {
1170 exfat_chain_set(&ei->dir, parent_ei->start_clu,
1171 EXFAT_B_TO_CLU_ROUND_UP(parent_isize, sbi),
1172 parent_ei->flags);
1176 /* rename or move a old file into a new file */
1177 static int __exfat_rename(struct inode *old_parent_inode,
1178 struct exfat_inode_info *ei, struct inode *new_parent_inode,
1179 struct dentry *new_dentry)
1181 int ret;
1182 int dentry;
1183 struct exfat_chain olddir, newdir;
1184 struct exfat_chain *p_dir = NULL;
1185 struct exfat_uni_name uni_name;
1186 struct exfat_dentry *ep;
1187 struct super_block *sb = old_parent_inode->i_sb;
1188 struct exfat_sb_info *sbi = EXFAT_SB(sb);
1189 const unsigned char *new_path = new_dentry->d_name.name;
1190 struct inode *new_inode = new_dentry->d_inode;
1191 int num_entries;
1192 struct exfat_inode_info *new_ei = NULL;
1193 unsigned int new_entry_type = TYPE_UNUSED;
1194 int new_entry = 0;
1195 struct buffer_head *old_bh, *new_bh = NULL;
1197 /* check the validity of pointer parameters */
1198 if (new_path == NULL || strlen(new_path) == 0)
1199 return -EINVAL;
1201 if (ei->dir.dir == DIR_DELETED) {
1202 exfat_err(sb, "abnormal access to deleted source dentry");
1203 return -ENOENT;
1206 exfat_update_parent_info(ei, old_parent_inode);
1208 exfat_chain_dup(&olddir, &ei->dir);
1209 dentry = ei->entry;
1211 ep = exfat_get_dentry(sb, &olddir, dentry, &old_bh, NULL);
1212 if (!ep) {
1213 ret = -EIO;
1214 goto out;
1216 brelse(old_bh);
1218 /* check whether new dir is existing directory and empty */
1219 if (new_inode) {
1220 ret = -EIO;
1221 new_ei = EXFAT_I(new_inode);
1223 if (new_ei->dir.dir == DIR_DELETED) {
1224 exfat_err(sb, "abnormal access to deleted target dentry");
1225 goto out;
1228 exfat_update_parent_info(new_ei, new_parent_inode);
1230 p_dir = &(new_ei->dir);
1231 new_entry = new_ei->entry;
1232 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1233 if (!ep)
1234 goto out;
1236 new_entry_type = exfat_get_entry_type(ep);
1237 brelse(new_bh);
1239 /* if new_inode exists, update ei */
1240 if (new_entry_type == TYPE_DIR) {
1241 struct exfat_chain new_clu;
1243 new_clu.dir = new_ei->start_clu;
1244 new_clu.size =
1245 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1246 sbi);
1247 new_clu.flags = new_ei->flags;
1249 ret = exfat_check_dir_empty(sb, &new_clu);
1250 if (ret)
1251 goto out;
1255 /* check the validity of directory name in the given new pathname */
1256 ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1257 &uni_name);
1258 if (ret)
1259 goto out;
1261 exfat_set_volume_dirty(sb);
1263 if (olddir.dir == newdir.dir)
1264 ret = exfat_rename_file(new_parent_inode, &olddir, dentry,
1265 &uni_name, ei);
1266 else
1267 ret = exfat_move_file(new_parent_inode, &olddir, dentry,
1268 &newdir, &uni_name, ei);
1270 if (!ret && new_inode) {
1271 /* delete entries of new_dir */
1272 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1273 if (!ep) {
1274 ret = -EIO;
1275 goto del_out;
1278 num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep);
1279 if (num_entries < 0) {
1280 ret = -EIO;
1281 goto del_out;
1283 brelse(new_bh);
1285 if (exfat_remove_entries(new_inode, p_dir, new_entry, 0,
1286 num_entries + 1)) {
1287 ret = -EIO;
1288 goto del_out;
1291 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1292 if (new_entry_type == TYPE_DIR) {
1293 /* new_ei, new_clu_to_free */
1294 struct exfat_chain new_clu_to_free;
1296 exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1297 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1298 sbi), new_ei->flags);
1300 if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1301 /* just set I/O error only */
1302 ret = -EIO;
1305 i_size_write(new_inode, 0);
1306 new_ei->start_clu = EXFAT_EOF_CLUSTER;
1307 new_ei->flags = ALLOC_NO_FAT_CHAIN;
1309 del_out:
1310 /* Update new_inode ei
1311 * Prevent syncing removed new_inode
1312 * (new_ei is already initialized above code ("if (new_inode)")
1314 new_ei->dir.dir = DIR_DELETED;
1316 exfat_clear_volume_dirty(sb);
1317 out:
1318 return ret;
1321 static int exfat_rename(struct inode *old_dir, struct dentry *old_dentry,
1322 struct inode *new_dir, struct dentry *new_dentry,
1323 unsigned int flags)
1325 struct inode *old_inode, *new_inode;
1326 struct super_block *sb = old_dir->i_sb;
1327 loff_t i_pos;
1328 int err;
1331 * The VFS already checks for existence, so for local filesystems
1332 * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1333 * Don't support any other flags
1335 if (flags & ~RENAME_NOREPLACE)
1336 return -EINVAL;
1338 mutex_lock(&EXFAT_SB(sb)->s_lock);
1339 old_inode = old_dentry->d_inode;
1340 new_inode = new_dentry->d_inode;
1342 err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1343 if (err)
1344 goto unlock;
1346 inode_inc_iversion(new_dir);
1347 new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
1348 EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1349 exfat_truncate_atime(&new_dir->i_atime);
1350 if (IS_DIRSYNC(new_dir))
1351 exfat_sync_inode(new_dir);
1352 else
1353 mark_inode_dirty(new_dir);
1355 i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1356 (EXFAT_I(old_inode)->entry & 0xffffffff);
1357 exfat_unhash_inode(old_inode);
1358 exfat_hash_inode(old_inode, i_pos);
1359 if (IS_DIRSYNC(new_dir))
1360 exfat_sync_inode(old_inode);
1361 else
1362 mark_inode_dirty(old_inode);
1364 if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1365 drop_nlink(old_dir);
1366 if (!new_inode)
1367 inc_nlink(new_dir);
1370 inode_inc_iversion(old_dir);
1371 old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1372 if (IS_DIRSYNC(old_dir))
1373 exfat_sync_inode(old_dir);
1374 else
1375 mark_inode_dirty(old_dir);
1377 if (new_inode) {
1378 exfat_unhash_inode(new_inode);
1380 /* skip drop_nlink if new_inode already has been dropped */
1381 if (new_inode->i_nlink) {
1382 drop_nlink(new_inode);
1383 if (S_ISDIR(new_inode->i_mode))
1384 drop_nlink(new_inode);
1385 } else {
1386 exfat_warn(sb, "abnormal access to an inode dropped");
1387 WARN_ON(new_inode->i_nlink == 0);
1389 new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime =
1390 current_time(new_inode);
1393 unlock:
1394 mutex_unlock(&EXFAT_SB(sb)->s_lock);
1395 return err;
1398 const struct inode_operations exfat_dir_inode_operations = {
1399 .create = exfat_create,
1400 .lookup = exfat_lookup,
1401 .unlink = exfat_unlink,
1402 .mkdir = exfat_mkdir,
1403 .rmdir = exfat_rmdir,
1404 .rename = exfat_rename,
1405 .setattr = exfat_setattr,
1406 .getattr = exfat_getattr,