xref: /linux/fs/exfat/namei.c (revision ac844e91364a03c35838fd488437605fbe56f8c3)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
4  */
5 
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>
11 
12 #include "exfat_raw.h"
13 #include "exfat_fs.h"
14 
15 static inline unsigned long exfat_d_version(struct dentry *dentry)
16 {
17 	return (unsigned long) dentry->d_fsdata;
18 }
19 
20 static inline void exfat_d_version_set(struct dentry *dentry,
21 		unsigned long version)
22 {
23 	dentry->d_fsdata = (void *) version;
24 }
25 
26 /*
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.
30  *
31  * If it happened, the negative dentry isn't actually negative anymore.  So,
32  * drop it.
33  */
34 static int exfat_d_revalidate(struct dentry *dentry, unsigned int flags)
35 {
36 	int ret;
37 
38 	if (flags & LOOKUP_RCU)
39 		return -ECHILD;
40 
41 	/*
42 	 * This is not negative dentry. Always valid.
43 	 *
44 	 * Note, rename() to existing directory entry will have ->d_inode, and
45 	 * will use existing name which isn't specified name by user.
46 	 *
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.
50 	 */
51 	if (d_really_is_positive(dentry))
52 		return 1;
53 
54 	/*
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.
57 	 */
58 	if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
59 		return 0;
60 
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;
66 }
67 
68 /* returns the length of a struct qstr, ignoring trailing dots if necessary */
69 static unsigned int exfat_striptail_len(unsigned int len, const char *name,
70 					bool keep_last_dots)
71 {
72 	if (!keep_last_dots) {
73 		while (len && name[len - 1] == '.')
74 			len--;
75 	}
76 	return len;
77 }
78 
79 /*
80  * Compute the hash for the exfat name corresponding to the dentry.  If the name
81  * is invalid, we leave the hash code unchanged so that the existing dentry can
82  * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate.
83  */
84 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
85 {
86 	struct super_block *sb = dentry->d_sb;
87 	struct nls_table *t = EXFAT_SB(sb)->nls_io;
88 	const unsigned char *name = qstr->name;
89 	unsigned int len = exfat_striptail_len(qstr->len, qstr->name,
90 			   EXFAT_SB(sb)->options.keep_last_dots);
91 	unsigned long hash = init_name_hash(dentry);
92 	int i, charlen;
93 	wchar_t c;
94 
95 	for (i = 0; i < len; i += charlen) {
96 		charlen = t->char2uni(&name[i], len - i, &c);
97 		if (charlen < 0)
98 			return charlen;
99 		hash = partial_name_hash(exfat_toupper(sb, c), hash);
100 	}
101 
102 	qstr->hash = end_name_hash(hash);
103 	return 0;
104 }
105 
106 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
107 		const char *str, const struct qstr *name)
108 {
109 	struct super_block *sb = dentry->d_sb;
110 	struct nls_table *t = EXFAT_SB(sb)->nls_io;
111 	unsigned int alen = exfat_striptail_len(name->len, name->name,
112 				EXFAT_SB(sb)->options.keep_last_dots);
113 	unsigned int blen = exfat_striptail_len(len, str,
114 				EXFAT_SB(sb)->options.keep_last_dots);
115 	wchar_t c1, c2;
116 	int charlen, i;
117 
118 	if (alen != blen)
119 		return 1;
120 
121 	for (i = 0; i < len; i += charlen) {
122 		charlen = t->char2uni(&name->name[i], alen - i, &c1);
123 		if (charlen < 0)
124 			return 1;
125 		if (charlen != t->char2uni(&str[i], blen - i, &c2))
126 			return 1;
127 
128 		if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
129 			return 1;
130 	}
131 
132 	return 0;
133 }
134 
135 const struct dentry_operations exfat_dentry_ops = {
136 	.d_revalidate	= exfat_d_revalidate,
137 	.d_hash		= exfat_d_hash,
138 	.d_compare	= exfat_d_cmp,
139 };
140 
141 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
142 {
143 	struct super_block *sb = dentry->d_sb;
144 	const unsigned char *name = qstr->name;
145 	unsigned int len = exfat_striptail_len(qstr->len, qstr->name,
146 			       EXFAT_SB(sb)->options.keep_last_dots);
147 	unsigned long hash = init_name_hash(dentry);
148 	int i, charlen;
149 	unicode_t u;
150 
151 	for (i = 0; i < len; i += charlen) {
152 		charlen = utf8_to_utf32(&name[i], len - i, &u);
153 		if (charlen < 0)
154 			return charlen;
155 
156 		/*
157 		 * exfat_toupper() works only for code points up to the U+FFFF.
158 		 */
159 		hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u,
160 					 hash);
161 	}
162 
163 	qstr->hash = end_name_hash(hash);
164 	return 0;
165 }
166 
167 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
168 		const char *str, const struct qstr *name)
169 {
170 	struct super_block *sb = dentry->d_sb;
171 	unsigned int alen = exfat_striptail_len(name->len, name->name,
172 				EXFAT_SB(sb)->options.keep_last_dots);
173 	unsigned int blen = exfat_striptail_len(len, str,
174 				EXFAT_SB(sb)->options.keep_last_dots);
175 
176 	unicode_t u_a, u_b;
177 	int charlen, i;
178 
179 	if (alen != blen)
180 		return 1;
181 
182 	for (i = 0; i < alen; i += charlen) {
183 		charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
184 		if (charlen < 0)
185 			return 1;
186 		if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
187 			return 1;
188 
189 		if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
190 			if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
191 				return 1;
192 		} else {
193 			if (u_a != u_b)
194 				return 1;
195 		}
196 	}
197 
198 	return 0;
199 }
200 
201 const struct dentry_operations exfat_utf8_dentry_ops = {
202 	.d_revalidate	= exfat_d_revalidate,
203 	.d_hash		= exfat_utf8_d_hash,
204 	.d_compare	= exfat_utf8_d_cmp,
205 };
206 
207 /* search EMPTY CONTINUOUS "num_entries" entries */
208 static int exfat_search_empty_slot(struct super_block *sb,
209 		struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
210 		int num_entries, struct exfat_entry_set_cache *es)
211 {
212 	int i, dentry, ret;
213 	int dentries_per_clu;
214 	struct exfat_chain clu;
215 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
216 	int total_entries = EXFAT_CLU_TO_DEN(p_dir->size, sbi);
217 
218 	dentries_per_clu = sbi->dentries_per_clu;
219 
220 	if (hint_femp->eidx != EXFAT_HINT_NONE) {
221 		dentry = hint_femp->eidx;
222 
223 		/*
224 		 * If hint_femp->count is enough, it is needed to check if
225 		 * there are actual empty entries.
226 		 * Otherwise, and if "dentry + hint_famp->count" is also equal
227 		 * to "p_dir->size * dentries_per_clu", it means ENOSPC.
228 		 */
229 		if (dentry + hint_femp->count == total_entries &&
230 		    num_entries > hint_femp->count)
231 			return -ENOSPC;
232 
233 		hint_femp->eidx = EXFAT_HINT_NONE;
234 		exfat_chain_dup(&clu, &hint_femp->cur);
235 	} else {
236 		exfat_chain_dup(&clu, p_dir);
237 		dentry = 0;
238 	}
239 
240 	while (dentry + num_entries < total_entries &&
241 	       clu.dir != EXFAT_EOF_CLUSTER) {
242 		i = dentry & (dentries_per_clu - 1);
243 
244 		ret = exfat_get_empty_dentry_set(es, sb, &clu, i, num_entries);
245 		if (ret < 0)
246 			return ret;
247 		else if (ret == 0)
248 			return dentry;
249 
250 		dentry += ret;
251 		i += ret;
252 
253 		while (i >= dentries_per_clu) {
254 			if (clu.flags == ALLOC_NO_FAT_CHAIN) {
255 				if (--clu.size > 0)
256 					clu.dir++;
257 				else
258 					clu.dir = EXFAT_EOF_CLUSTER;
259 			} else {
260 				if (exfat_get_next_cluster(sb, &clu.dir))
261 					return -EIO;
262 			}
263 
264 			i -= dentries_per_clu;
265 		}
266 	}
267 
268 	hint_femp->eidx = dentry;
269 	hint_femp->count = 0;
270 	if (dentry == total_entries || clu.dir == EXFAT_EOF_CLUSTER)
271 		exfat_chain_set(&hint_femp->cur, EXFAT_EOF_CLUSTER, 0,
272 				clu.flags);
273 	else
274 		hint_femp->cur = clu;
275 
276 	return -ENOSPC;
277 }
278 
279 static int exfat_check_max_dentries(struct inode *inode)
280 {
281 	if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
282 		/*
283 		 * exFAT spec allows a dir to grow up to 8388608(256MB)
284 		 * dentries
285 		 */
286 		return -ENOSPC;
287 	}
288 	return 0;
289 }
290 
291 /* find empty directory entry.
292  * if there isn't any empty slot, expand cluster chain.
293  */
294 static int exfat_find_empty_entry(struct inode *inode,
295 		struct exfat_chain *p_dir, int num_entries,
296 		struct exfat_entry_set_cache *es)
297 {
298 	int dentry;
299 	unsigned int ret, last_clu;
300 	loff_t size = 0;
301 	struct exfat_chain clu;
302 	struct super_block *sb = inode->i_sb;
303 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
304 	struct exfat_inode_info *ei = EXFAT_I(inode);
305 	struct exfat_hint_femp hint_femp;
306 
307 	hint_femp.eidx = EXFAT_HINT_NONE;
308 
309 	if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
310 		hint_femp = ei->hint_femp;
311 		ei->hint_femp.eidx = EXFAT_HINT_NONE;
312 	}
313 
314 	while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
315 					num_entries, es)) < 0) {
316 		if (dentry == -EIO)
317 			break;
318 
319 		if (exfat_check_max_dentries(inode))
320 			return -ENOSPC;
321 
322 		/*
323 		 * Allocate new cluster to this directory
324 		 */
325 		if (ei->start_clu != EXFAT_EOF_CLUSTER) {
326 			/* we trust p_dir->size regardless of FAT type */
327 			if (exfat_find_last_cluster(sb, p_dir, &last_clu))
328 				return -EIO;
329 
330 			exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
331 		} else {
332 			/* This directory is empty */
333 			exfat_chain_set(&clu, EXFAT_EOF_CLUSTER, 0,
334 					ALLOC_NO_FAT_CHAIN);
335 		}
336 
337 		/* allocate a cluster */
338 		ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode));
339 		if (ret)
340 			return ret;
341 
342 		if (exfat_zeroed_cluster(inode, clu.dir))
343 			return -EIO;
344 
345 		if (ei->start_clu == EXFAT_EOF_CLUSTER) {
346 			ei->start_clu = clu.dir;
347 			p_dir->dir = clu.dir;
348 			hint_femp.eidx = 0;
349 		}
350 
351 		/* append to the FAT chain */
352 		if (clu.flags != p_dir->flags) {
353 			/* no-fat-chain bit is disabled,
354 			 * so fat-chain should be synced with alloc-bitmap
355 			 */
356 			exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
357 			p_dir->flags = ALLOC_FAT_CHAIN;
358 			hint_femp.cur.flags = ALLOC_FAT_CHAIN;
359 		}
360 
361 		if (clu.flags == ALLOC_FAT_CHAIN)
362 			if (exfat_ent_set(sb, last_clu, clu.dir))
363 				return -EIO;
364 
365 		if (hint_femp.cur.dir == EXFAT_EOF_CLUSTER)
366 			exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
367 
368 		hint_femp.count += sbi->dentries_per_clu;
369 
370 		hint_femp.cur.size++;
371 		p_dir->size++;
372 		size = EXFAT_CLU_TO_B(p_dir->size, sbi);
373 
374 		/* directory inode should be updated in here */
375 		i_size_write(inode, size);
376 		ei->valid_size += sbi->cluster_size;
377 		ei->flags = p_dir->flags;
378 		inode->i_blocks += sbi->cluster_size >> 9;
379 	}
380 
381 	return dentry;
382 }
383 
384 /*
385  * Name Resolution Functions :
386  * Zero if it was successful; otherwise nonzero.
387  */
388 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
389 		struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
390 		int lookup)
391 {
392 	int namelen;
393 	int lossy = NLS_NAME_NO_LOSSY;
394 	struct super_block *sb = inode->i_sb;
395 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
396 	struct exfat_inode_info *ei = EXFAT_I(inode);
397 	int pathlen = strlen(path);
398 
399 	/*
400 	 * get the length of the pathname excluding
401 	 * trailing periods, if any.
402 	 */
403 	namelen = exfat_striptail_len(pathlen, path, false);
404 	if (EXFAT_SB(sb)->options.keep_last_dots) {
405 		/*
406 		 * Do not allow the creation of files with names
407 		 * ending with period(s).
408 		 */
409 		if (!lookup && (namelen < pathlen))
410 			return -EINVAL;
411 		namelen = pathlen;
412 	}
413 	if (!namelen)
414 		return -ENOENT;
415 	if (pathlen > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
416 		return -ENAMETOOLONG;
417 
418 	/*
419 	 * strip all leading spaces :
420 	 * "MS windows 7" supports leading spaces.
421 	 * So we should skip this preprocessing for compatibility.
422 	 */
423 
424 	/* file name conversion :
425 	 * If lookup case, we allow bad-name for compatibility.
426 	 */
427 	namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
428 			&lossy);
429 	if (namelen < 0)
430 		return namelen; /* return error value */
431 
432 	if ((lossy && !lookup) || !namelen)
433 		return (lossy & NLS_NAME_OVERLEN) ? -ENAMETOOLONG : -EINVAL;
434 
435 	exfat_chain_set(p_dir, ei->start_clu,
436 		EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
437 
438 	return 0;
439 }
440 
441 static inline int exfat_resolve_path(struct inode *inode,
442 		const unsigned char *path, struct exfat_chain *dir,
443 		struct exfat_uni_name *uni)
444 {
445 	return __exfat_resolve_path(inode, path, dir, uni, 0);
446 }
447 
448 static inline int exfat_resolve_path_for_lookup(struct inode *inode,
449 		const unsigned char *path, struct exfat_chain *dir,
450 		struct exfat_uni_name *uni)
451 {
452 	return __exfat_resolve_path(inode, path, dir, uni, 1);
453 }
454 
455 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
456 {
457 	return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
458 }
459 
460 static int exfat_add_entry(struct inode *inode, const char *path,
461 		struct exfat_chain *p_dir, unsigned int type,
462 		struct exfat_dir_entry *info)
463 {
464 	int ret, dentry, num_entries;
465 	struct super_block *sb = inode->i_sb;
466 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
467 	struct exfat_uni_name uniname;
468 	struct exfat_chain clu;
469 	struct timespec64 ts = current_time(inode);
470 	struct exfat_entry_set_cache es;
471 	int clu_size = 0;
472 	unsigned int start_clu = EXFAT_FREE_CLUSTER;
473 
474 	ret = exfat_resolve_path(inode, path, p_dir, &uniname);
475 	if (ret)
476 		goto out;
477 
478 	num_entries = exfat_calc_num_entries(&uniname);
479 	if (num_entries < 0) {
480 		ret = num_entries;
481 		goto out;
482 	}
483 
484 	/* exfat_find_empty_entry must be called before alloc_cluster() */
485 	dentry = exfat_find_empty_entry(inode, p_dir, num_entries, &es);
486 	if (dentry < 0) {
487 		ret = dentry; /* -EIO or -ENOSPC */
488 		goto out;
489 	}
490 
491 	if (type == TYPE_DIR && !sbi->options.zero_size_dir) {
492 		ret = exfat_alloc_new_dir(inode, &clu);
493 		if (ret) {
494 			exfat_put_dentry_set(&es, false);
495 			goto out;
496 		}
497 		start_clu = clu.dir;
498 		clu_size = sbi->cluster_size;
499 	}
500 
501 	/* update the directory entry */
502 	/* fill the dos name directory entry information of the created file.
503 	 * the first cluster is not determined yet. (0)
504 	 */
505 	exfat_init_dir_entry(&es, type, start_clu, clu_size, &ts);
506 	exfat_init_ext_entry(&es, num_entries, &uniname);
507 
508 	ret = exfat_put_dentry_set(&es, IS_DIRSYNC(inode));
509 	if (ret)
510 		goto out;
511 
512 	info->dir = *p_dir;
513 	info->entry = dentry;
514 	info->flags = ALLOC_NO_FAT_CHAIN;
515 	info->type = type;
516 
517 	if (type == TYPE_FILE) {
518 		info->attr = EXFAT_ATTR_ARCHIVE;
519 		info->start_clu = EXFAT_EOF_CLUSTER;
520 		info->size = 0;
521 		info->num_subdirs = 0;
522 	} else {
523 		info->attr = EXFAT_ATTR_SUBDIR;
524 		if (sbi->options.zero_size_dir)
525 			info->start_clu = EXFAT_EOF_CLUSTER;
526 		else
527 			info->start_clu = start_clu;
528 		info->size = clu_size;
529 		info->num_subdirs = EXFAT_MIN_SUBDIR;
530 	}
531 	info->valid_size = info->size;
532 
533 	memset(&info->crtime, 0, sizeof(info->crtime));
534 	memset(&info->mtime, 0, sizeof(info->mtime));
535 	memset(&info->atime, 0, sizeof(info->atime));
536 out:
537 	return ret;
538 }
539 
540 static int exfat_create(struct mnt_idmap *idmap, struct inode *dir,
541 			struct dentry *dentry, umode_t mode, bool excl)
542 {
543 	struct super_block *sb = dir->i_sb;
544 	struct inode *inode;
545 	struct exfat_chain cdir;
546 	struct exfat_dir_entry info;
547 	loff_t i_pos;
548 	int err;
549 	loff_t size = i_size_read(dir);
550 
551 	if (unlikely(exfat_forced_shutdown(sb)))
552 		return -EIO;
553 
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 	if (err)
559 		goto unlock;
560 
561 	inode_inc_iversion(dir);
562 	inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
563 	if (IS_DIRSYNC(dir) && size != i_size_read(dir))
564 		exfat_sync_inode(dir);
565 	else
566 		mark_inode_dirty(dir);
567 
568 	i_pos = exfat_make_i_pos(&info);
569 	inode = exfat_build_inode(sb, &info, i_pos);
570 	err = PTR_ERR_OR_ZERO(inode);
571 	if (err)
572 		goto unlock;
573 
574 	inode_inc_iversion(inode);
575 	EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode);
576 	exfat_truncate_inode_atime(inode);
577 
578 	/* timestamp is already written, so mark_inode_dirty() is unneeded. */
579 
580 	d_instantiate(dentry, inode);
581 unlock:
582 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
583 	return err;
584 }
585 
586 /* lookup a file */
587 static int exfat_find(struct inode *dir, struct qstr *qname,
588 		struct exfat_dir_entry *info)
589 {
590 	int ret, dentry, count;
591 	struct exfat_chain cdir;
592 	struct exfat_uni_name uni_name;
593 	struct super_block *sb = dir->i_sb;
594 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
595 	struct exfat_inode_info *ei = EXFAT_I(dir);
596 	struct exfat_dentry *ep, *ep2;
597 	struct exfat_entry_set_cache es;
598 	/* for optimized dir & entry to prevent long traverse of cluster chain */
599 	struct exfat_hint hint_opt;
600 
601 	if (qname->len == 0)
602 		return -ENOENT;
603 
604 	/* check the validity of directory name in the given pathname */
605 	ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name);
606 	if (ret)
607 		return ret;
608 
609 	/* check the validation of hint_stat and initialize it if required */
610 	if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
611 		ei->hint_stat.clu = cdir.dir;
612 		ei->hint_stat.eidx = 0;
613 		ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
614 		ei->hint_femp.eidx = EXFAT_HINT_NONE;
615 	}
616 
617 	/* search the file name for directories */
618 	dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name, &hint_opt);
619 	if (dentry < 0)
620 		return dentry; /* -error value */
621 
622 	info->dir = cdir;
623 	info->entry = dentry;
624 	info->num_subdirs = 0;
625 
626 	/* adjust cdir to the optimized value */
627 	cdir.dir = hint_opt.clu;
628 	if (cdir.flags & ALLOC_NO_FAT_CHAIN)
629 		cdir.size -= dentry / sbi->dentries_per_clu;
630 	dentry = hint_opt.eidx;
631 	if (exfat_get_dentry_set(&es, sb, &cdir, dentry, ES_2_ENTRIES))
632 		return -EIO;
633 	ep = exfat_get_dentry_cached(&es, ES_IDX_FILE);
634 	ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM);
635 
636 	info->type = exfat_get_entry_type(ep);
637 	info->attr = le16_to_cpu(ep->dentry.file.attr);
638 	info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
639 	info->valid_size = le64_to_cpu(ep2->dentry.stream.valid_size);
640 	info->size = le64_to_cpu(ep2->dentry.stream.size);
641 
642 	info->start_clu = le32_to_cpu(ep2->dentry.stream.start_clu);
643 	if (!is_valid_cluster(sbi, info->start_clu) && info->size) {
644 		exfat_warn(sb, "start_clu is invalid cluster(0x%x)",
645 				info->start_clu);
646 		info->size = 0;
647 		info->valid_size = 0;
648 	}
649 
650 	if (info->valid_size > info->size) {
651 		exfat_warn(sb, "valid_size(%lld) is greater than size(%lld)",
652 				info->valid_size, info->size);
653 		info->valid_size = info->size;
654 	}
655 
656 	if (info->size == 0) {
657 		info->flags = ALLOC_NO_FAT_CHAIN;
658 		info->start_clu = EXFAT_EOF_CLUSTER;
659 	} else
660 		info->flags = ep2->dentry.stream.flags;
661 
662 	exfat_get_entry_time(sbi, &info->crtime,
663 			     ep->dentry.file.create_tz,
664 			     ep->dentry.file.create_time,
665 			     ep->dentry.file.create_date,
666 			     ep->dentry.file.create_time_cs);
667 	exfat_get_entry_time(sbi, &info->mtime,
668 			     ep->dentry.file.modify_tz,
669 			     ep->dentry.file.modify_time,
670 			     ep->dentry.file.modify_date,
671 			     ep->dentry.file.modify_time_cs);
672 	exfat_get_entry_time(sbi, &info->atime,
673 			     ep->dentry.file.access_tz,
674 			     ep->dentry.file.access_time,
675 			     ep->dentry.file.access_date,
676 			     0);
677 	exfat_put_dentry_set(&es, false);
678 
679 	if (ei->start_clu == EXFAT_FREE_CLUSTER) {
680 		exfat_fs_error(sb,
681 			       "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
682 			       i_size_read(dir), ei->dir.dir, ei->entry);
683 		return -EIO;
684 	}
685 
686 	if (info->type == TYPE_DIR) {
687 		exfat_chain_set(&cdir, info->start_clu,
688 				EXFAT_B_TO_CLU(info->size, sbi), info->flags);
689 		count = exfat_count_dir_entries(sb, &cdir);
690 		if (count < 0)
691 			return -EIO;
692 
693 		info->num_subdirs = count + EXFAT_MIN_SUBDIR;
694 	}
695 	return 0;
696 }
697 
698 static int exfat_d_anon_disconn(struct dentry *dentry)
699 {
700 	return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
701 }
702 
703 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
704 		unsigned int flags)
705 {
706 	struct super_block *sb = dir->i_sb;
707 	struct inode *inode;
708 	struct dentry *alias;
709 	struct exfat_dir_entry info;
710 	int err;
711 	loff_t i_pos;
712 	mode_t i_mode;
713 
714 	mutex_lock(&EXFAT_SB(sb)->s_lock);
715 	err = exfat_find(dir, &dentry->d_name, &info);
716 	if (err) {
717 		if (err == -ENOENT) {
718 			inode = NULL;
719 			goto out;
720 		}
721 		goto unlock;
722 	}
723 
724 	i_pos = exfat_make_i_pos(&info);
725 	inode = exfat_build_inode(sb, &info, i_pos);
726 	err = PTR_ERR_OR_ZERO(inode);
727 	if (err)
728 		goto unlock;
729 
730 	i_mode = inode->i_mode;
731 	alias = d_find_alias(inode);
732 
733 	/*
734 	 * Checking "alias->d_parent == dentry->d_parent" to make sure
735 	 * FS is not corrupted (especially double linked dir).
736 	 */
737 	if (alias && alias->d_parent == dentry->d_parent &&
738 			!exfat_d_anon_disconn(alias)) {
739 
740 		/*
741 		 * Unhashed alias is able to exist because of revalidate()
742 		 * called by lookup_fast. You can easily make this status
743 		 * by calling create and lookup concurrently
744 		 * In such case, we reuse an alias instead of new dentry
745 		 */
746 		if (d_unhashed(alias)) {
747 			WARN_ON(alias->d_name.hash_len !=
748 				dentry->d_name.hash_len);
749 			exfat_info(sb, "rehashed a dentry(%p) in read lookup",
750 				   alias);
751 			d_drop(dentry);
752 			d_rehash(alias);
753 		} else if (!S_ISDIR(i_mode)) {
754 			/*
755 			 * This inode has non anonymous-DCACHE_DISCONNECTED
756 			 * dentry. This means, the user did ->lookup() by an
757 			 * another name (longname vs 8.3 alias of it) in past.
758 			 *
759 			 * Switch to new one for reason of locality if possible.
760 			 */
761 			d_move(alias, dentry);
762 		}
763 		iput(inode);
764 		mutex_unlock(&EXFAT_SB(sb)->s_lock);
765 		return alias;
766 	}
767 	dput(alias);
768 out:
769 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
770 	if (!inode)
771 		exfat_d_version_set(dentry, inode_query_iversion(dir));
772 
773 	return d_splice_alias(inode, dentry);
774 unlock:
775 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
776 	return ERR_PTR(err);
777 }
778 
779 /* remove an entry, BUT don't truncate */
780 static int exfat_unlink(struct inode *dir, struct dentry *dentry)
781 {
782 	struct super_block *sb = dir->i_sb;
783 	struct inode *inode = dentry->d_inode;
784 	struct exfat_inode_info *ei = EXFAT_I(inode);
785 	struct exfat_entry_set_cache es;
786 	int err = 0;
787 
788 	if (unlikely(exfat_forced_shutdown(sb)))
789 		return -EIO;
790 
791 	mutex_lock(&EXFAT_SB(sb)->s_lock);
792 	if (ei->dir.dir == DIR_DELETED) {
793 		exfat_err(sb, "abnormal access to deleted dentry");
794 		err = -ENOENT;
795 		goto unlock;
796 	}
797 
798 	err = exfat_get_dentry_set_by_ei(&es, sb, ei);
799 	if (err) {
800 		err = -EIO;
801 		goto unlock;
802 	}
803 
804 	exfat_set_volume_dirty(sb);
805 
806 	/* update the directory entry */
807 	exfat_remove_entries(inode, &es, ES_IDX_FILE);
808 
809 	err = exfat_put_dentry_set(&es, IS_DIRSYNC(inode));
810 	if (err)
811 		goto unlock;
812 
813 	/* This doesn't modify ei */
814 	ei->dir.dir = DIR_DELETED;
815 
816 	inode_inc_iversion(dir);
817 	simple_inode_init_ts(dir);
818 	exfat_truncate_inode_atime(dir);
819 	mark_inode_dirty(dir);
820 
821 	clear_nlink(inode);
822 	simple_inode_init_ts(inode);
823 	exfat_truncate_inode_atime(inode);
824 	exfat_unhash_inode(inode);
825 	exfat_d_version_set(dentry, inode_query_iversion(dir));
826 unlock:
827 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
828 	return err;
829 }
830 
831 static int exfat_mkdir(struct mnt_idmap *idmap, struct inode *dir,
832 		       struct dentry *dentry, umode_t mode)
833 {
834 	struct super_block *sb = dir->i_sb;
835 	struct inode *inode;
836 	struct exfat_dir_entry info;
837 	struct exfat_chain cdir;
838 	loff_t i_pos;
839 	int err;
840 	loff_t size = i_size_read(dir);
841 
842 	if (unlikely(exfat_forced_shutdown(sb)))
843 		return -EIO;
844 
845 	mutex_lock(&EXFAT_SB(sb)->s_lock);
846 	exfat_set_volume_dirty(sb);
847 	err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
848 		&info);
849 	if (err)
850 		goto unlock;
851 
852 	inode_inc_iversion(dir);
853 	inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
854 	if (IS_DIRSYNC(dir) && size != i_size_read(dir))
855 		exfat_sync_inode(dir);
856 	else
857 		mark_inode_dirty(dir);
858 	inc_nlink(dir);
859 
860 	i_pos = exfat_make_i_pos(&info);
861 	inode = exfat_build_inode(sb, &info, i_pos);
862 	err = PTR_ERR_OR_ZERO(inode);
863 	if (err)
864 		goto unlock;
865 
866 	inode_inc_iversion(inode);
867 	EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode);
868 	exfat_truncate_inode_atime(inode);
869 	/* timestamp is already written, so mark_inode_dirty() is unneeded. */
870 
871 	d_instantiate(dentry, inode);
872 
873 unlock:
874 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
875 	return err;
876 }
877 
878 static int exfat_check_dir_empty(struct super_block *sb,
879 		struct exfat_chain *p_dir)
880 {
881 	int i, dentries_per_clu;
882 	unsigned int type;
883 	struct exfat_chain clu;
884 	struct exfat_dentry *ep;
885 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
886 	struct buffer_head *bh;
887 
888 	dentries_per_clu = sbi->dentries_per_clu;
889 
890 	if (p_dir->dir == EXFAT_EOF_CLUSTER)
891 		return 0;
892 
893 	exfat_chain_dup(&clu, p_dir);
894 
895 	while (clu.dir != EXFAT_EOF_CLUSTER) {
896 		for (i = 0; i < dentries_per_clu; i++) {
897 			ep = exfat_get_dentry(sb, &clu, i, &bh);
898 			if (!ep)
899 				return -EIO;
900 			type = exfat_get_entry_type(ep);
901 			brelse(bh);
902 			if (type == TYPE_UNUSED)
903 				return 0;
904 
905 			if (type != TYPE_FILE && type != TYPE_DIR)
906 				continue;
907 
908 			return -ENOTEMPTY;
909 		}
910 
911 		if (clu.flags == ALLOC_NO_FAT_CHAIN) {
912 			if (--clu.size > 0)
913 				clu.dir++;
914 			else
915 				clu.dir = EXFAT_EOF_CLUSTER;
916 		} else {
917 			if (exfat_get_next_cluster(sb, &(clu.dir)))
918 				return -EIO;
919 		}
920 	}
921 
922 	return 0;
923 }
924 
925 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
926 {
927 	struct inode *inode = dentry->d_inode;
928 	struct exfat_chain clu_to_free;
929 	struct super_block *sb = inode->i_sb;
930 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
931 	struct exfat_inode_info *ei = EXFAT_I(inode);
932 	struct exfat_entry_set_cache es;
933 	int err;
934 
935 	if (unlikely(exfat_forced_shutdown(sb)))
936 		return -EIO;
937 
938 	mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
939 
940 	if (ei->dir.dir == DIR_DELETED) {
941 		exfat_err(sb, "abnormal access to deleted dentry");
942 		err = -ENOENT;
943 		goto unlock;
944 	}
945 
946 	exfat_chain_set(&clu_to_free, ei->start_clu,
947 		EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
948 
949 	err = exfat_check_dir_empty(sb, &clu_to_free);
950 	if (err) {
951 		if (err == -EIO)
952 			exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)",
953 				  err);
954 		goto unlock;
955 	}
956 
957 	err = exfat_get_dentry_set_by_ei(&es, sb, ei);
958 	if (err) {
959 		err = -EIO;
960 		goto unlock;
961 	}
962 
963 	exfat_set_volume_dirty(sb);
964 
965 	exfat_remove_entries(inode, &es, ES_IDX_FILE);
966 
967 	err = exfat_put_dentry_set(&es, IS_DIRSYNC(dir));
968 	if (err)
969 		goto unlock;
970 
971 	ei->dir.dir = DIR_DELETED;
972 
973 	inode_inc_iversion(dir);
974 	simple_inode_init_ts(dir);
975 	exfat_truncate_inode_atime(dir);
976 	if (IS_DIRSYNC(dir))
977 		exfat_sync_inode(dir);
978 	else
979 		mark_inode_dirty(dir);
980 	drop_nlink(dir);
981 
982 	clear_nlink(inode);
983 	simple_inode_init_ts(inode);
984 	exfat_truncate_inode_atime(inode);
985 	exfat_unhash_inode(inode);
986 	exfat_d_version_set(dentry, inode_query_iversion(dir));
987 unlock:
988 	mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
989 	return err;
990 }
991 
992 static int exfat_rename_file(struct inode *parent_inode,
993 		struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
994 		struct exfat_inode_info *ei)
995 {
996 	int ret, num_new_entries;
997 	struct exfat_dentry *epold, *epnew;
998 	struct super_block *sb = parent_inode->i_sb;
999 	struct exfat_entry_set_cache old_es, new_es;
1000 	int sync = IS_DIRSYNC(parent_inode);
1001 
1002 	if (unlikely(exfat_forced_shutdown(sb)))
1003 		return -EIO;
1004 
1005 	num_new_entries = exfat_calc_num_entries(p_uniname);
1006 	if (num_new_entries < 0)
1007 		return num_new_entries;
1008 
1009 	ret = exfat_get_dentry_set_by_ei(&old_es, sb, ei);
1010 	if (ret) {
1011 		ret = -EIO;
1012 		return ret;
1013 	}
1014 
1015 	epold = exfat_get_dentry_cached(&old_es, ES_IDX_FILE);
1016 
1017 	if (old_es.num_entries < num_new_entries) {
1018 		int newentry;
1019 
1020 		newentry = exfat_find_empty_entry(parent_inode, p_dir, num_new_entries,
1021 				&new_es);
1022 		if (newentry < 0) {
1023 			ret = newentry; /* -EIO or -ENOSPC */
1024 			goto put_old_es;
1025 		}
1026 
1027 		epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE);
1028 		*epnew = *epold;
1029 		if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1030 			epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1031 			ei->attr |= EXFAT_ATTR_ARCHIVE;
1032 		}
1033 
1034 		epold = exfat_get_dentry_cached(&old_es, ES_IDX_STREAM);
1035 		epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM);
1036 		*epnew = *epold;
1037 
1038 		exfat_init_ext_entry(&new_es, num_new_entries, p_uniname);
1039 
1040 		ret = exfat_put_dentry_set(&new_es, sync);
1041 		if (ret)
1042 			goto put_old_es;
1043 
1044 		exfat_remove_entries(parent_inode, &old_es, ES_IDX_FILE);
1045 		ei->dir = *p_dir;
1046 		ei->entry = newentry;
1047 	} else {
1048 		if (exfat_get_entry_type(epold) == TYPE_FILE) {
1049 			epold->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1050 			ei->attr |= EXFAT_ATTR_ARCHIVE;
1051 		}
1052 
1053 		exfat_remove_entries(parent_inode, &old_es, ES_IDX_FIRST_FILENAME + 1);
1054 		exfat_init_ext_entry(&old_es, num_new_entries, p_uniname);
1055 	}
1056 	return exfat_put_dentry_set(&old_es, sync);
1057 
1058 put_old_es:
1059 	exfat_put_dentry_set(&old_es, false);
1060 	return ret;
1061 }
1062 
1063 static int exfat_move_file(struct inode *parent_inode,
1064 		struct exfat_chain *p_newdir, struct exfat_uni_name *p_uniname,
1065 		struct exfat_inode_info *ei)
1066 {
1067 	int ret, newentry, num_new_entries;
1068 	struct exfat_dentry *epmov, *epnew;
1069 	struct exfat_entry_set_cache mov_es, new_es;
1070 
1071 	num_new_entries = exfat_calc_num_entries(p_uniname);
1072 	if (num_new_entries < 0)
1073 		return num_new_entries;
1074 
1075 	ret = exfat_get_dentry_set_by_ei(&mov_es, parent_inode->i_sb, ei);
1076 	if (ret)
1077 		return -EIO;
1078 
1079 	newentry = exfat_find_empty_entry(parent_inode, p_newdir, num_new_entries,
1080 			&new_es);
1081 	if (newentry < 0) {
1082 		ret = newentry; /* -EIO or -ENOSPC */
1083 		goto put_mov_es;
1084 	}
1085 
1086 	epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_FILE);
1087 	epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE);
1088 	*epnew = *epmov;
1089 	if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1090 		epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1091 		ei->attr |= EXFAT_ATTR_ARCHIVE;
1092 	}
1093 
1094 	epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_STREAM);
1095 	epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM);
1096 	*epnew = *epmov;
1097 
1098 	exfat_init_ext_entry(&new_es, num_new_entries, p_uniname);
1099 	exfat_remove_entries(parent_inode, &mov_es, ES_IDX_FILE);
1100 
1101 	exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1102 		p_newdir->flags);
1103 
1104 	ei->entry = newentry;
1105 
1106 	ret = exfat_put_dentry_set(&new_es, IS_DIRSYNC(parent_inode));
1107 	if (ret)
1108 		goto put_mov_es;
1109 
1110 	return exfat_put_dentry_set(&mov_es, IS_DIRSYNC(parent_inode));
1111 
1112 put_mov_es:
1113 	exfat_put_dentry_set(&mov_es, false);
1114 
1115 	return ret;
1116 }
1117 
1118 /* rename or move a old file into a new file */
1119 static int __exfat_rename(struct inode *old_parent_inode,
1120 		struct exfat_inode_info *ei, struct inode *new_parent_inode,
1121 		struct dentry *new_dentry)
1122 {
1123 	int ret;
1124 	struct exfat_chain newdir;
1125 	struct exfat_uni_name uni_name;
1126 	struct super_block *sb = old_parent_inode->i_sb;
1127 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
1128 	const unsigned char *new_path = new_dentry->d_name.name;
1129 	struct inode *new_inode = new_dentry->d_inode;
1130 	struct exfat_inode_info *new_ei = NULL;
1131 
1132 	/* check the validity of pointer parameters */
1133 	if (new_path == NULL || strlen(new_path) == 0)
1134 		return -EINVAL;
1135 
1136 	if (ei->dir.dir == DIR_DELETED) {
1137 		exfat_err(sb, "abnormal access to deleted source dentry");
1138 		return -ENOENT;
1139 	}
1140 
1141 	/* check whether new dir is existing directory and empty */
1142 	if (new_inode) {
1143 		ret = -EIO;
1144 		new_ei = EXFAT_I(new_inode);
1145 
1146 		if (new_ei->dir.dir == DIR_DELETED) {
1147 			exfat_err(sb, "abnormal access to deleted target dentry");
1148 			goto out;
1149 		}
1150 
1151 		/* if new_inode exists, update ei */
1152 		if (S_ISDIR(new_inode->i_mode)) {
1153 			struct exfat_chain new_clu;
1154 
1155 			new_clu.dir = new_ei->start_clu;
1156 			new_clu.size =
1157 				EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1158 				sbi);
1159 			new_clu.flags = new_ei->flags;
1160 
1161 			ret = exfat_check_dir_empty(sb, &new_clu);
1162 			if (ret)
1163 				goto out;
1164 		}
1165 	}
1166 
1167 	/* check the validity of directory name in the given new pathname */
1168 	ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1169 			&uni_name);
1170 	if (ret)
1171 		goto out;
1172 
1173 	exfat_set_volume_dirty(sb);
1174 
1175 	if (new_parent_inode == old_parent_inode)
1176 		ret = exfat_rename_file(new_parent_inode, &newdir,
1177 				&uni_name, ei);
1178 	else
1179 		ret = exfat_move_file(new_parent_inode, &newdir,
1180 				&uni_name, ei);
1181 
1182 	if (!ret && new_inode) {
1183 		struct exfat_entry_set_cache es;
1184 
1185 		/* delete entries of new_dir */
1186 		ret = exfat_get_dentry_set_by_ei(&es, sb, new_ei);
1187 		if (ret) {
1188 			ret = -EIO;
1189 			goto del_out;
1190 		}
1191 
1192 		exfat_remove_entries(new_inode, &es, ES_IDX_FILE);
1193 
1194 		ret = exfat_put_dentry_set(&es, IS_DIRSYNC(new_inode));
1195 		if (ret)
1196 			goto del_out;
1197 
1198 		/* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1199 		if (S_ISDIR(new_inode->i_mode) &&
1200 		    new_ei->start_clu != EXFAT_EOF_CLUSTER) {
1201 			/* new_ei, new_clu_to_free */
1202 			struct exfat_chain new_clu_to_free;
1203 
1204 			exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1205 				EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1206 				sbi), new_ei->flags);
1207 
1208 			if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1209 				/* just set I/O error only */
1210 				ret = -EIO;
1211 			}
1212 
1213 			i_size_write(new_inode, 0);
1214 			new_ei->valid_size = 0;
1215 			new_ei->start_clu = EXFAT_EOF_CLUSTER;
1216 			new_ei->flags = ALLOC_NO_FAT_CHAIN;
1217 		}
1218 del_out:
1219 		/* Update new_inode ei
1220 		 * Prevent syncing removed new_inode
1221 		 * (new_ei is already initialized above code ("if (new_inode)")
1222 		 */
1223 		new_ei->dir.dir = DIR_DELETED;
1224 	}
1225 out:
1226 	return ret;
1227 }
1228 
1229 static int exfat_rename(struct mnt_idmap *idmap,
1230 			struct inode *old_dir, struct dentry *old_dentry,
1231 			struct inode *new_dir, struct dentry *new_dentry,
1232 			unsigned int flags)
1233 {
1234 	struct inode *old_inode, *new_inode;
1235 	struct super_block *sb = old_dir->i_sb;
1236 	loff_t i_pos;
1237 	int err;
1238 	loff_t size = i_size_read(new_dir);
1239 
1240 	/*
1241 	 * The VFS already checks for existence, so for local filesystems
1242 	 * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1243 	 * Don't support any other flags
1244 	 */
1245 	if (flags & ~RENAME_NOREPLACE)
1246 		return -EINVAL;
1247 
1248 	mutex_lock(&EXFAT_SB(sb)->s_lock);
1249 	old_inode = old_dentry->d_inode;
1250 	new_inode = new_dentry->d_inode;
1251 
1252 	err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1253 	if (err)
1254 		goto unlock;
1255 
1256 	inode_inc_iversion(new_dir);
1257 	simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry);
1258 	EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1259 	exfat_truncate_inode_atime(new_dir);
1260 	if (IS_DIRSYNC(new_dir) && size != i_size_read(new_dir))
1261 		exfat_sync_inode(new_dir);
1262 	else
1263 		mark_inode_dirty(new_dir);
1264 
1265 	i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1266 		(EXFAT_I(old_inode)->entry & 0xffffffff);
1267 	exfat_unhash_inode(old_inode);
1268 	exfat_hash_inode(old_inode, i_pos);
1269 	if (IS_DIRSYNC(new_dir))
1270 		exfat_sync_inode(old_inode);
1271 	else
1272 		mark_inode_dirty(old_inode);
1273 
1274 	if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1275 		drop_nlink(old_dir);
1276 		if (!new_inode)
1277 			inc_nlink(new_dir);
1278 	}
1279 
1280 	inode_inc_iversion(old_dir);
1281 	if (new_dir != old_dir)
1282 		mark_inode_dirty(old_dir);
1283 
1284 	if (new_inode) {
1285 		exfat_unhash_inode(new_inode);
1286 
1287 		/* skip drop_nlink if new_inode already has been dropped */
1288 		if (new_inode->i_nlink) {
1289 			drop_nlink(new_inode);
1290 			if (S_ISDIR(new_inode->i_mode))
1291 				drop_nlink(new_inode);
1292 		} else {
1293 			exfat_warn(sb, "abnormal access to an inode dropped");
1294 			WARN_ON(new_inode->i_nlink == 0);
1295 		}
1296 		EXFAT_I(new_inode)->i_crtime = current_time(new_inode);
1297 	}
1298 
1299 unlock:
1300 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
1301 	return err;
1302 }
1303 
1304 const struct inode_operations exfat_dir_inode_operations = {
1305 	.create		= exfat_create,
1306 	.lookup		= exfat_lookup,
1307 	.unlink		= exfat_unlink,
1308 	.mkdir		= exfat_mkdir,
1309 	.rmdir		= exfat_rmdir,
1310 	.rename		= exfat_rename,
1311 	.setattr	= exfat_setattr,
1312 	.getattr	= exfat_getattr,
1313 };
1314