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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 
exfat_d_version(struct dentry * dentry)15 static inline unsigned long exfat_d_version(struct dentry *dentry)
16 {
17 	return (unsigned long) dentry->d_fsdata;
18 }
19 
exfat_d_version_set(struct dentry * dentry,unsigned long version)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  */
exfat_d_revalidate(struct dentry * dentry,unsigned int flags)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 */
exfat_striptail_len(unsigned int len,const char * name,bool keep_last_dots)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  */
exfat_d_hash(const struct dentry * dentry,struct qstr * qstr)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 
exfat_d_cmp(const struct dentry * dentry,unsigned int len,const char * str,const struct qstr * name)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 
exfat_utf8_d_hash(const struct dentry * dentry,struct qstr * qstr)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 
exfat_utf8_d_cmp(const struct dentry * dentry,unsigned int len,const char * str,const struct qstr * name)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 */
exfat_search_empty_slot(struct super_block * sb,struct exfat_hint_femp * hint_femp,struct exfat_chain * p_dir,int num_entries,struct exfat_entry_set_cache * es)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 
exfat_check_max_dentries(struct inode * inode)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  */
exfat_find_empty_entry(struct inode * inode,struct exfat_chain * p_dir,int num_entries,struct exfat_entry_set_cache * es)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  */
__exfat_resolve_path(struct inode * inode,const unsigned char * path,struct exfat_chain * p_dir,struct exfat_uni_name * p_uniname,int lookup)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 
exfat_resolve_path(struct inode * inode,const unsigned char * path,struct exfat_chain * dir,struct exfat_uni_name * uni)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 
exfat_resolve_path_for_lookup(struct inode * inode,const unsigned char * path,struct exfat_chain * dir,struct exfat_uni_name * uni)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 
exfat_make_i_pos(struct exfat_dir_entry * info)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 
exfat_add_entry(struct inode * inode,const char * path,struct exfat_chain * p_dir,unsigned int type,struct exfat_dir_entry * info)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 
exfat_create(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,bool excl)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 */
exfat_find(struct inode * dir,struct qstr * qname,struct exfat_dir_entry * info)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 	if (unlikely(EXFAT_B_TO_CLU_ROUND_UP(info->size, sbi) > sbi->used_clusters)) {
643 		exfat_fs_error(sb, "data size is invalid(%lld)", info->size);
644 		return -EIO;
645 	}
646 
647 	info->start_clu = le32_to_cpu(ep2->dentry.stream.start_clu);
648 	if (!is_valid_cluster(sbi, info->start_clu) && info->size) {
649 		exfat_warn(sb, "start_clu is invalid cluster(0x%x)",
650 				info->start_clu);
651 		info->size = 0;
652 		info->valid_size = 0;
653 	}
654 
655 	if (info->valid_size > info->size) {
656 		exfat_warn(sb, "valid_size(%lld) is greater than size(%lld)",
657 				info->valid_size, info->size);
658 		info->valid_size = info->size;
659 	}
660 
661 	if (info->size == 0) {
662 		info->flags = ALLOC_NO_FAT_CHAIN;
663 		info->start_clu = EXFAT_EOF_CLUSTER;
664 	} else
665 		info->flags = ep2->dentry.stream.flags;
666 
667 	exfat_get_entry_time(sbi, &info->crtime,
668 			     ep->dentry.file.create_tz,
669 			     ep->dentry.file.create_time,
670 			     ep->dentry.file.create_date,
671 			     ep->dentry.file.create_time_cs);
672 	exfat_get_entry_time(sbi, &info->mtime,
673 			     ep->dentry.file.modify_tz,
674 			     ep->dentry.file.modify_time,
675 			     ep->dentry.file.modify_date,
676 			     ep->dentry.file.modify_time_cs);
677 	exfat_get_entry_time(sbi, &info->atime,
678 			     ep->dentry.file.access_tz,
679 			     ep->dentry.file.access_time,
680 			     ep->dentry.file.access_date,
681 			     0);
682 	exfat_put_dentry_set(&es, false);
683 
684 	if (ei->start_clu == EXFAT_FREE_CLUSTER) {
685 		exfat_fs_error(sb,
686 			       "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
687 			       i_size_read(dir), ei->dir.dir, ei->entry);
688 		return -EIO;
689 	}
690 
691 	if (info->type == TYPE_DIR) {
692 		exfat_chain_set(&cdir, info->start_clu,
693 				EXFAT_B_TO_CLU(info->size, sbi), info->flags);
694 		count = exfat_count_dir_entries(sb, &cdir);
695 		if (count < 0)
696 			return -EIO;
697 
698 		info->num_subdirs = count + EXFAT_MIN_SUBDIR;
699 	}
700 	return 0;
701 }
702 
exfat_d_anon_disconn(struct dentry * dentry)703 static int exfat_d_anon_disconn(struct dentry *dentry)
704 {
705 	return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
706 }
707 
exfat_lookup(struct inode * dir,struct dentry * dentry,unsigned int flags)708 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
709 		unsigned int flags)
710 {
711 	struct super_block *sb = dir->i_sb;
712 	struct inode *inode;
713 	struct dentry *alias;
714 	struct exfat_dir_entry info;
715 	int err;
716 	loff_t i_pos;
717 	mode_t i_mode;
718 
719 	mutex_lock(&EXFAT_SB(sb)->s_lock);
720 	err = exfat_find(dir, &dentry->d_name, &info);
721 	if (err) {
722 		if (err == -ENOENT) {
723 			inode = NULL;
724 			goto out;
725 		}
726 		goto unlock;
727 	}
728 
729 	i_pos = exfat_make_i_pos(&info);
730 	inode = exfat_build_inode(sb, &info, i_pos);
731 	err = PTR_ERR_OR_ZERO(inode);
732 	if (err)
733 		goto unlock;
734 
735 	i_mode = inode->i_mode;
736 	alias = d_find_alias(inode);
737 
738 	/*
739 	 * Checking "alias->d_parent == dentry->d_parent" to make sure
740 	 * FS is not corrupted (especially double linked dir).
741 	 */
742 	if (alias && alias->d_parent == dentry->d_parent &&
743 			!exfat_d_anon_disconn(alias)) {
744 
745 		/*
746 		 * Unhashed alias is able to exist because of revalidate()
747 		 * called by lookup_fast. You can easily make this status
748 		 * by calling create and lookup concurrently
749 		 * In such case, we reuse an alias instead of new dentry
750 		 */
751 		if (d_unhashed(alias)) {
752 			WARN_ON(alias->d_name.hash_len !=
753 				dentry->d_name.hash_len);
754 			exfat_info(sb, "rehashed a dentry(%p) in read lookup",
755 				   alias);
756 			d_drop(dentry);
757 			d_rehash(alias);
758 		} else if (!S_ISDIR(i_mode)) {
759 			/*
760 			 * This inode has non anonymous-DCACHE_DISCONNECTED
761 			 * dentry. This means, the user did ->lookup() by an
762 			 * another name (longname vs 8.3 alias of it) in past.
763 			 *
764 			 * Switch to new one for reason of locality if possible.
765 			 */
766 			d_move(alias, dentry);
767 		}
768 		iput(inode);
769 		mutex_unlock(&EXFAT_SB(sb)->s_lock);
770 		return alias;
771 	}
772 	dput(alias);
773 out:
774 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
775 	if (!inode)
776 		exfat_d_version_set(dentry, inode_query_iversion(dir));
777 
778 	return d_splice_alias(inode, dentry);
779 unlock:
780 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
781 	return ERR_PTR(err);
782 }
783 
784 /* remove an entry, BUT don't truncate */
exfat_unlink(struct inode * dir,struct dentry * dentry)785 static int exfat_unlink(struct inode *dir, struct dentry *dentry)
786 {
787 	struct exfat_chain cdir;
788 	struct super_block *sb = dir->i_sb;
789 	struct inode *inode = dentry->d_inode;
790 	struct exfat_inode_info *ei = EXFAT_I(inode);
791 	struct exfat_entry_set_cache es;
792 	int entry, err = 0;
793 
794 	if (unlikely(exfat_forced_shutdown(sb)))
795 		return -EIO;
796 
797 	mutex_lock(&EXFAT_SB(sb)->s_lock);
798 	exfat_chain_dup(&cdir, &ei->dir);
799 	entry = ei->entry;
800 	if (ei->dir.dir == DIR_DELETED) {
801 		exfat_err(sb, "abnormal access to deleted dentry");
802 		err = -ENOENT;
803 		goto unlock;
804 	}
805 
806 	err = exfat_get_dentry_set(&es, sb, &cdir, entry, ES_ALL_ENTRIES);
807 	if (err) {
808 		err = -EIO;
809 		goto unlock;
810 	}
811 
812 	exfat_set_volume_dirty(sb);
813 
814 	/* update the directory entry */
815 	exfat_remove_entries(inode, &es, ES_IDX_FILE);
816 
817 	err = exfat_put_dentry_set(&es, IS_DIRSYNC(inode));
818 	if (err)
819 		goto unlock;
820 
821 	/* This doesn't modify ei */
822 	ei->dir.dir = DIR_DELETED;
823 
824 	inode_inc_iversion(dir);
825 	simple_inode_init_ts(dir);
826 	exfat_truncate_inode_atime(dir);
827 	mark_inode_dirty(dir);
828 
829 	clear_nlink(inode);
830 	simple_inode_init_ts(inode);
831 	exfat_truncate_inode_atime(inode);
832 	exfat_unhash_inode(inode);
833 	exfat_d_version_set(dentry, inode_query_iversion(dir));
834 unlock:
835 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
836 	return err;
837 }
838 
exfat_mkdir(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)839 static int exfat_mkdir(struct mnt_idmap *idmap, struct inode *dir,
840 		       struct dentry *dentry, umode_t mode)
841 {
842 	struct super_block *sb = dir->i_sb;
843 	struct inode *inode;
844 	struct exfat_dir_entry info;
845 	struct exfat_chain cdir;
846 	loff_t i_pos;
847 	int err;
848 	loff_t size = i_size_read(dir);
849 
850 	if (unlikely(exfat_forced_shutdown(sb)))
851 		return -EIO;
852 
853 	mutex_lock(&EXFAT_SB(sb)->s_lock);
854 	exfat_set_volume_dirty(sb);
855 	err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
856 		&info);
857 	if (err)
858 		goto unlock;
859 
860 	inode_inc_iversion(dir);
861 	inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
862 	if (IS_DIRSYNC(dir) && size != i_size_read(dir))
863 		exfat_sync_inode(dir);
864 	else
865 		mark_inode_dirty(dir);
866 	inc_nlink(dir);
867 
868 	i_pos = exfat_make_i_pos(&info);
869 	inode = exfat_build_inode(sb, &info, i_pos);
870 	err = PTR_ERR_OR_ZERO(inode);
871 	if (err)
872 		goto unlock;
873 
874 	inode_inc_iversion(inode);
875 	EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode);
876 	exfat_truncate_inode_atime(inode);
877 	/* timestamp is already written, so mark_inode_dirty() is unneeded. */
878 
879 	d_instantiate(dentry, inode);
880 
881 unlock:
882 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
883 	return err;
884 }
885 
exfat_check_dir_empty(struct super_block * sb,struct exfat_chain * p_dir)886 static int exfat_check_dir_empty(struct super_block *sb,
887 		struct exfat_chain *p_dir)
888 {
889 	int i, dentries_per_clu;
890 	unsigned int type;
891 	unsigned int clu_count = 0;
892 	struct exfat_chain clu;
893 	struct exfat_dentry *ep;
894 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
895 	struct buffer_head *bh;
896 
897 	dentries_per_clu = sbi->dentries_per_clu;
898 
899 	if (p_dir->dir == EXFAT_EOF_CLUSTER)
900 		return 0;
901 
902 	exfat_chain_dup(&clu, p_dir);
903 
904 	while (clu.dir != EXFAT_EOF_CLUSTER) {
905 		for (i = 0; i < dentries_per_clu; i++) {
906 			ep = exfat_get_dentry(sb, &clu, i, &bh);
907 			if (!ep)
908 				return -EIO;
909 			type = exfat_get_entry_type(ep);
910 			brelse(bh);
911 			if (type == TYPE_UNUSED)
912 				return 0;
913 
914 			if (type != TYPE_FILE && type != TYPE_DIR)
915 				continue;
916 
917 			return -ENOTEMPTY;
918 		}
919 
920 		if (clu.flags == ALLOC_NO_FAT_CHAIN) {
921 			if (--clu.size > 0)
922 				clu.dir++;
923 			else
924 				clu.dir = EXFAT_EOF_CLUSTER;
925 		} else {
926 			if (exfat_get_next_cluster(sb, &(clu.dir)))
927 				return -EIO;
928 
929 			/* break if the cluster chain includes a loop */
930 			if (unlikely(++clu_count > EXFAT_DATA_CLUSTER_COUNT(sbi)))
931 				break;
932 		}
933 	}
934 
935 	return 0;
936 }
937 
exfat_rmdir(struct inode * dir,struct dentry * dentry)938 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
939 {
940 	struct inode *inode = dentry->d_inode;
941 	struct exfat_chain cdir, clu_to_free;
942 	struct super_block *sb = inode->i_sb;
943 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
944 	struct exfat_inode_info *ei = EXFAT_I(inode);
945 	struct exfat_entry_set_cache es;
946 	int entry, err;
947 
948 	if (unlikely(exfat_forced_shutdown(sb)))
949 		return -EIO;
950 
951 	mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
952 
953 	exfat_chain_dup(&cdir, &ei->dir);
954 	entry = ei->entry;
955 
956 	if (ei->dir.dir == DIR_DELETED) {
957 		exfat_err(sb, "abnormal access to deleted dentry");
958 		err = -ENOENT;
959 		goto unlock;
960 	}
961 
962 	exfat_chain_set(&clu_to_free, ei->start_clu,
963 		EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
964 
965 	err = exfat_check_dir_empty(sb, &clu_to_free);
966 	if (err) {
967 		if (err == -EIO)
968 			exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)",
969 				  err);
970 		goto unlock;
971 	}
972 
973 	err = exfat_get_dentry_set(&es, sb, &cdir, entry, ES_ALL_ENTRIES);
974 	if (err) {
975 		err = -EIO;
976 		goto unlock;
977 	}
978 
979 	exfat_set_volume_dirty(sb);
980 
981 	exfat_remove_entries(inode, &es, ES_IDX_FILE);
982 
983 	err = exfat_put_dentry_set(&es, IS_DIRSYNC(dir));
984 	if (err)
985 		goto unlock;
986 
987 	ei->dir.dir = DIR_DELETED;
988 
989 	inode_inc_iversion(dir);
990 	simple_inode_init_ts(dir);
991 	exfat_truncate_inode_atime(dir);
992 	if (IS_DIRSYNC(dir))
993 		exfat_sync_inode(dir);
994 	else
995 		mark_inode_dirty(dir);
996 	drop_nlink(dir);
997 
998 	clear_nlink(inode);
999 	simple_inode_init_ts(inode);
1000 	exfat_truncate_inode_atime(inode);
1001 	exfat_unhash_inode(inode);
1002 	exfat_d_version_set(dentry, inode_query_iversion(dir));
1003 unlock:
1004 	mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
1005 	return err;
1006 }
1007 
exfat_rename_file(struct inode * inode,struct exfat_chain * p_dir,int oldentry,struct exfat_uni_name * p_uniname,struct exfat_inode_info * ei)1008 static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
1009 		int oldentry, struct exfat_uni_name *p_uniname,
1010 		struct exfat_inode_info *ei)
1011 {
1012 	int ret, num_new_entries;
1013 	struct exfat_dentry *epold, *epnew;
1014 	struct super_block *sb = inode->i_sb;
1015 	struct exfat_entry_set_cache old_es, new_es;
1016 	int sync = IS_DIRSYNC(inode);
1017 
1018 	if (unlikely(exfat_forced_shutdown(sb)))
1019 		return -EIO;
1020 
1021 	num_new_entries = exfat_calc_num_entries(p_uniname);
1022 	if (num_new_entries < 0)
1023 		return num_new_entries;
1024 
1025 	ret = exfat_get_dentry_set(&old_es, sb, p_dir, oldentry, ES_ALL_ENTRIES);
1026 	if (ret) {
1027 		ret = -EIO;
1028 		return ret;
1029 	}
1030 
1031 	epold = exfat_get_dentry_cached(&old_es, ES_IDX_FILE);
1032 
1033 	if (old_es.num_entries < num_new_entries) {
1034 		int newentry;
1035 
1036 		newentry = exfat_find_empty_entry(inode, p_dir, num_new_entries,
1037 				&new_es);
1038 		if (newentry < 0) {
1039 			ret = newentry; /* -EIO or -ENOSPC */
1040 			goto put_old_es;
1041 		}
1042 
1043 		epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE);
1044 		*epnew = *epold;
1045 		if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1046 			epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1047 			ei->attr |= EXFAT_ATTR_ARCHIVE;
1048 		}
1049 
1050 		epold = exfat_get_dentry_cached(&old_es, ES_IDX_STREAM);
1051 		epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM);
1052 		*epnew = *epold;
1053 
1054 		exfat_init_ext_entry(&new_es, num_new_entries, p_uniname);
1055 
1056 		ret = exfat_put_dentry_set(&new_es, sync);
1057 		if (ret)
1058 			goto put_old_es;
1059 
1060 		exfat_remove_entries(inode, &old_es, ES_IDX_FILE);
1061 		ei->dir = *p_dir;
1062 		ei->entry = newentry;
1063 	} else {
1064 		if (exfat_get_entry_type(epold) == TYPE_FILE) {
1065 			epold->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1066 			ei->attr |= EXFAT_ATTR_ARCHIVE;
1067 		}
1068 
1069 		exfat_remove_entries(inode, &old_es, ES_IDX_FIRST_FILENAME + 1);
1070 		exfat_init_ext_entry(&old_es, num_new_entries, p_uniname);
1071 	}
1072 	return exfat_put_dentry_set(&old_es, sync);
1073 
1074 put_old_es:
1075 	exfat_put_dentry_set(&old_es, false);
1076 	return ret;
1077 }
1078 
exfat_move_file(struct inode * inode,struct exfat_chain * p_olddir,int oldentry,struct exfat_chain * p_newdir,struct exfat_uni_name * p_uniname,struct exfat_inode_info * ei)1079 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
1080 		int oldentry, struct exfat_chain *p_newdir,
1081 		struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1082 {
1083 	int ret, newentry, num_new_entries;
1084 	struct exfat_dentry *epmov, *epnew;
1085 	struct super_block *sb = inode->i_sb;
1086 	struct exfat_entry_set_cache mov_es, new_es;
1087 
1088 	num_new_entries = exfat_calc_num_entries(p_uniname);
1089 	if (num_new_entries < 0)
1090 		return num_new_entries;
1091 
1092 	ret = exfat_get_dentry_set(&mov_es, sb, p_olddir, oldentry,
1093 			ES_ALL_ENTRIES);
1094 	if (ret)
1095 		return -EIO;
1096 
1097 	newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries,
1098 			&new_es);
1099 	if (newentry < 0) {
1100 		ret = newentry; /* -EIO or -ENOSPC */
1101 		goto put_mov_es;
1102 	}
1103 
1104 	epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_FILE);
1105 	epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE);
1106 	*epnew = *epmov;
1107 	if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1108 		epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE);
1109 		ei->attr |= EXFAT_ATTR_ARCHIVE;
1110 	}
1111 
1112 	epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_STREAM);
1113 	epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM);
1114 	*epnew = *epmov;
1115 
1116 	exfat_init_ext_entry(&new_es, num_new_entries, p_uniname);
1117 	exfat_remove_entries(inode, &mov_es, ES_IDX_FILE);
1118 
1119 	exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1120 		p_newdir->flags);
1121 
1122 	ei->entry = newentry;
1123 
1124 	ret = exfat_put_dentry_set(&new_es, IS_DIRSYNC(inode));
1125 	if (ret)
1126 		goto put_mov_es;
1127 
1128 	return exfat_put_dentry_set(&mov_es, IS_DIRSYNC(inode));
1129 
1130 put_mov_es:
1131 	exfat_put_dentry_set(&mov_es, false);
1132 
1133 	return ret;
1134 }
1135 
1136 /* rename or move a old file into a new file */
__exfat_rename(struct inode * old_parent_inode,struct exfat_inode_info * ei,struct inode * new_parent_inode,struct dentry * new_dentry)1137 static int __exfat_rename(struct inode *old_parent_inode,
1138 		struct exfat_inode_info *ei, struct inode *new_parent_inode,
1139 		struct dentry *new_dentry)
1140 {
1141 	int ret;
1142 	int dentry;
1143 	struct exfat_chain olddir, newdir;
1144 	struct exfat_chain *p_dir = NULL;
1145 	struct exfat_uni_name uni_name;
1146 	struct exfat_dentry *ep;
1147 	struct super_block *sb = old_parent_inode->i_sb;
1148 	struct exfat_sb_info *sbi = EXFAT_SB(sb);
1149 	const unsigned char *new_path = new_dentry->d_name.name;
1150 	struct inode *new_inode = new_dentry->d_inode;
1151 	struct exfat_inode_info *new_ei = NULL;
1152 	unsigned int new_entry_type = TYPE_UNUSED;
1153 	int new_entry = 0;
1154 	struct buffer_head *new_bh = NULL;
1155 
1156 	/* check the validity of pointer parameters */
1157 	if (new_path == NULL || strlen(new_path) == 0)
1158 		return -EINVAL;
1159 
1160 	if (ei->dir.dir == DIR_DELETED) {
1161 		exfat_err(sb, "abnormal access to deleted source dentry");
1162 		return -ENOENT;
1163 	}
1164 
1165 	exfat_chain_set(&olddir, EXFAT_I(old_parent_inode)->start_clu,
1166 		EXFAT_B_TO_CLU_ROUND_UP(i_size_read(old_parent_inode), sbi),
1167 		EXFAT_I(old_parent_inode)->flags);
1168 	dentry = ei->entry;
1169 
1170 	/* check whether new dir is existing directory and empty */
1171 	if (new_inode) {
1172 		ret = -EIO;
1173 		new_ei = EXFAT_I(new_inode);
1174 
1175 		if (new_ei->dir.dir == DIR_DELETED) {
1176 			exfat_err(sb, "abnormal access to deleted target dentry");
1177 			goto out;
1178 		}
1179 
1180 		p_dir = &(new_ei->dir);
1181 		new_entry = new_ei->entry;
1182 		ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh);
1183 		if (!ep)
1184 			goto out;
1185 
1186 		new_entry_type = exfat_get_entry_type(ep);
1187 		brelse(new_bh);
1188 
1189 		/* if new_inode exists, update ei */
1190 		if (new_entry_type == TYPE_DIR) {
1191 			struct exfat_chain new_clu;
1192 
1193 			new_clu.dir = new_ei->start_clu;
1194 			new_clu.size =
1195 				EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1196 				sbi);
1197 			new_clu.flags = new_ei->flags;
1198 
1199 			ret = exfat_check_dir_empty(sb, &new_clu);
1200 			if (ret)
1201 				goto out;
1202 		}
1203 	}
1204 
1205 	/* check the validity of directory name in the given new pathname */
1206 	ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1207 			&uni_name);
1208 	if (ret)
1209 		goto out;
1210 
1211 	exfat_set_volume_dirty(sb);
1212 
1213 	if (olddir.dir == newdir.dir)
1214 		ret = exfat_rename_file(new_parent_inode, &olddir, dentry,
1215 				&uni_name, ei);
1216 	else
1217 		ret = exfat_move_file(new_parent_inode, &olddir, dentry,
1218 				&newdir, &uni_name, ei);
1219 
1220 	if (!ret && new_inode) {
1221 		struct exfat_entry_set_cache es;
1222 
1223 		/* delete entries of new_dir */
1224 		ret = exfat_get_dentry_set(&es, sb, p_dir, new_entry,
1225 				ES_ALL_ENTRIES);
1226 		if (ret) {
1227 			ret = -EIO;
1228 			goto del_out;
1229 		}
1230 
1231 		exfat_remove_entries(new_inode, &es, ES_IDX_FILE);
1232 
1233 		ret = exfat_put_dentry_set(&es, IS_DIRSYNC(new_inode));
1234 		if (ret)
1235 			goto del_out;
1236 
1237 		/* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1238 		if (new_entry_type == TYPE_DIR &&
1239 		    new_ei->start_clu != EXFAT_EOF_CLUSTER) {
1240 			/* new_ei, new_clu_to_free */
1241 			struct exfat_chain new_clu_to_free;
1242 
1243 			exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1244 				EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1245 				sbi), new_ei->flags);
1246 
1247 			if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1248 				/* just set I/O error only */
1249 				ret = -EIO;
1250 			}
1251 
1252 			i_size_write(new_inode, 0);
1253 			new_ei->valid_size = 0;
1254 			new_ei->start_clu = EXFAT_EOF_CLUSTER;
1255 			new_ei->flags = ALLOC_NO_FAT_CHAIN;
1256 		}
1257 del_out:
1258 		/* Update new_inode ei
1259 		 * Prevent syncing removed new_inode
1260 		 * (new_ei is already initialized above code ("if (new_inode)")
1261 		 */
1262 		new_ei->dir.dir = DIR_DELETED;
1263 	}
1264 out:
1265 	return ret;
1266 }
1267 
exfat_rename(struct mnt_idmap * idmap,struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry,unsigned int flags)1268 static int exfat_rename(struct mnt_idmap *idmap,
1269 			struct inode *old_dir, struct dentry *old_dentry,
1270 			struct inode *new_dir, struct dentry *new_dentry,
1271 			unsigned int flags)
1272 {
1273 	struct inode *old_inode, *new_inode;
1274 	struct super_block *sb = old_dir->i_sb;
1275 	loff_t i_pos;
1276 	int err;
1277 	loff_t size = i_size_read(new_dir);
1278 
1279 	/*
1280 	 * The VFS already checks for existence, so for local filesystems
1281 	 * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1282 	 * Don't support any other flags
1283 	 */
1284 	if (flags & ~RENAME_NOREPLACE)
1285 		return -EINVAL;
1286 
1287 	mutex_lock(&EXFAT_SB(sb)->s_lock);
1288 	old_inode = old_dentry->d_inode;
1289 	new_inode = new_dentry->d_inode;
1290 
1291 	err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1292 	if (err)
1293 		goto unlock;
1294 
1295 	inode_inc_iversion(new_dir);
1296 	simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry);
1297 	EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1298 	exfat_truncate_inode_atime(new_dir);
1299 	if (IS_DIRSYNC(new_dir) && size != i_size_read(new_dir))
1300 		exfat_sync_inode(new_dir);
1301 	else
1302 		mark_inode_dirty(new_dir);
1303 
1304 	i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1305 		(EXFAT_I(old_inode)->entry & 0xffffffff);
1306 	exfat_unhash_inode(old_inode);
1307 	exfat_hash_inode(old_inode, i_pos);
1308 	if (IS_DIRSYNC(new_dir))
1309 		exfat_sync_inode(old_inode);
1310 	else
1311 		mark_inode_dirty(old_inode);
1312 
1313 	if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1314 		drop_nlink(old_dir);
1315 		if (!new_inode)
1316 			inc_nlink(new_dir);
1317 	}
1318 
1319 	inode_inc_iversion(old_dir);
1320 	if (new_dir != old_dir)
1321 		mark_inode_dirty(old_dir);
1322 
1323 	if (new_inode) {
1324 		exfat_unhash_inode(new_inode);
1325 
1326 		/* skip drop_nlink if new_inode already has been dropped */
1327 		if (new_inode->i_nlink) {
1328 			drop_nlink(new_inode);
1329 			if (S_ISDIR(new_inode->i_mode))
1330 				drop_nlink(new_inode);
1331 		} else {
1332 			exfat_warn(sb, "abnormal access to an inode dropped");
1333 			WARN_ON(new_inode->i_nlink == 0);
1334 		}
1335 		EXFAT_I(new_inode)->i_crtime = current_time(new_inode);
1336 	}
1337 
1338 unlock:
1339 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
1340 	return err;
1341 }
1342 
1343 const struct inode_operations exfat_dir_inode_operations = {
1344 	.create		= exfat_create,
1345 	.lookup		= exfat_lookup,
1346 	.unlink		= exfat_unlink,
1347 	.mkdir		= exfat_mkdir,
1348 	.rmdir		= exfat_rmdir,
1349 	.rename		= exfat_rename,
1350 	.setattr	= exfat_setattr,
1351 	.getattr	= exfat_getattr,
1352 };
1353