Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
 */

#ifndef _EXFAT_FS_H
#define _EXFAT_FS_H

#include <linux/fs.h>
#include <linux/ratelimit.h>
#include <linux/nls.h>

#define EXFAT_ROOT_INO		1

#define EXFAT_CLUSTERS_UNTRACKED (~0u)

/*
 * exfat error flags
 */
enum exfat_error_mode {
	EXFAT_ERRORS_CONT,	/* ignore error and continue */
	EXFAT_ERRORS_PANIC,	/* panic on error */
	EXFAT_ERRORS_RO,	/* remount r/o on error */
};

/*
 * exfat nls lossy flag
 */
enum {
	NLS_NAME_NO_LOSSY =	0,	/* no lossy */
	NLS_NAME_LOSSY =	1 << 0,	/* just detected incorrect filename(s) */
	NLS_NAME_OVERLEN =	1 << 1,	/* the length is over than its limit */
};

#define EXFAT_HASH_BITS		8
#define EXFAT_HASH_SIZE		(1UL << EXFAT_HASH_BITS)

/*
 * Type Definitions
 */
#define ES_2_ENTRIES		2
#define ES_ALL_ENTRIES		0

#define DIR_DELETED		0xFFFFFFF7

/* type values */
#define TYPE_UNUSED		0x0000
#define TYPE_DELETED		0x0001
#define TYPE_INVALID		0x0002
#define TYPE_CRITICAL_PRI	0x0100
#define TYPE_BITMAP		0x0101
#define TYPE_UPCASE		0x0102
#define TYPE_VOLUME		0x0103
#define TYPE_DIR		0x0104
#define TYPE_FILE		0x011F
#define TYPE_CRITICAL_SEC	0x0200
#define TYPE_STREAM		0x0201
#define TYPE_EXTEND		0x0202
#define TYPE_ACL		0x0203
#define TYPE_BENIGN_PRI		0x0400
#define TYPE_GUID		0x0401
#define TYPE_PADDING		0x0402
#define TYPE_ACLTAB		0x0403
#define TYPE_BENIGN_SEC		0x0800
#define TYPE_ALL		0x0FFF

#define MAX_CHARSET_SIZE	6 /* max size of multi-byte character */
#define MAX_NAME_LENGTH		255 /* max len of file name excluding NULL */
#define MAX_VFSNAME_BUF_SIZE	((MAX_NAME_LENGTH + 1) * MAX_CHARSET_SIZE)

/* Enough size to hold 256 dentry (even 512 Byte sector) */
#define DIR_CACHE_SIZE		(256*sizeof(struct exfat_dentry)/512+1)

#define EXFAT_HINT_NONE		-1
#define EXFAT_MIN_SUBDIR	2

/*
 * helpers for cluster size to byte conversion.
 */
#define EXFAT_CLU_TO_B(b, sbi)		((b) << (sbi)->cluster_size_bits)
#define EXFAT_B_TO_CLU(b, sbi)		((b) >> (sbi)->cluster_size_bits)
#define EXFAT_B_TO_CLU_ROUND_UP(b, sbi)	\
	(((b - 1) >> (sbi)->cluster_size_bits) + 1)
#define EXFAT_CLU_OFFSET(off, sbi)	((off) & ((sbi)->cluster_size - 1))

/*
 * helpers for block size to byte conversion.
 */
#define EXFAT_BLK_TO_B(b, sb)		((b) << (sb)->s_blocksize_bits)
#define EXFAT_B_TO_BLK(b, sb)		((b) >> (sb)->s_blocksize_bits)
#define EXFAT_B_TO_BLK_ROUND_UP(b, sb)	\
	(((b - 1) >> (sb)->s_blocksize_bits) + 1)
#define EXFAT_BLK_OFFSET(off, sb)	((off) & ((sb)->s_blocksize - 1))

/*
 * helpers for block size to dentry size conversion.
 */
#define EXFAT_B_TO_DEN_IDX(b, sbi)	\
	((b) << ((sbi)->cluster_size_bits - DENTRY_SIZE_BITS))
#define EXFAT_B_TO_DEN(b)		((b) >> DENTRY_SIZE_BITS)
#define EXFAT_DEN_TO_B(b)		((b) << DENTRY_SIZE_BITS)

/*
 * helpers for fat entry.
 */
#define FAT_ENT_SIZE (4)
#define FAT_ENT_SIZE_BITS (2)
#define FAT_ENT_OFFSET_SECTOR(sb, loc) (EXFAT_SB(sb)->FAT1_start_sector + \
	(((u64)loc << FAT_ENT_SIZE_BITS) >> sb->s_blocksize_bits))
#define FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc)	\
	((loc << FAT_ENT_SIZE_BITS) & (sb->s_blocksize - 1))

/*
 * helpers for bitmap.
 */
#define CLUSTER_TO_BITMAP_ENT(clu) ((clu) - EXFAT_RESERVED_CLUSTERS)
#define BITMAP_ENT_TO_CLUSTER(ent) ((ent) + EXFAT_RESERVED_CLUSTERS)
#define BITS_PER_SECTOR(sb) ((sb)->s_blocksize * BITS_PER_BYTE)
#define BITS_PER_SECTOR_MASK(sb) (BITS_PER_SECTOR(sb) - 1)
#define BITMAP_OFFSET_SECTOR_INDEX(sb, ent) \
	((ent / BITS_PER_BYTE) >> (sb)->s_blocksize_bits)
#define BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent) (ent & BITS_PER_SECTOR_MASK(sb))
#define BITMAP_OFFSET_BYTE_IN_SECTOR(sb, ent) \
	((ent / BITS_PER_BYTE) & ((sb)->s_blocksize - 1))
#define BITS_PER_BYTE_MASK	0x7
#define IGNORED_BITS_REMAINED(clu, clu_base) ((1 << ((clu) - (clu_base))) - 1)

struct exfat_dentry_namebuf {
	char *lfn;
	int lfnbuf_len; /* usually MAX_UNINAME_BUF_SIZE */
};

/* unicode name structure */
struct exfat_uni_name {
	/* +3 for null and for converting */
	unsigned short name[MAX_NAME_LENGTH + 3];
	u16 name_hash;
	unsigned char name_len;
};

/* directory structure */
struct exfat_chain {
	unsigned int dir;
	unsigned int size;
	unsigned char flags;
};

/* first empty entry hint information */
struct exfat_hint_femp {
	/* entry index of a directory */
	int eidx;
	/* count of continuous empty entry */
	int count;
	/* the cluster that first empty slot exists in */
	struct exfat_chain cur;
};

/* hint structure */
struct exfat_hint {
	unsigned int clu;
	union {
		unsigned int off; /* cluster offset */
		int eidx; /* entry index */
	};
};

struct exfat_entry_set_cache {
	struct super_block *sb;
	bool modified;
	unsigned int start_off;
	int num_bh;
	struct buffer_head *bh[DIR_CACHE_SIZE];
	unsigned int num_entries;
};

struct exfat_dir_entry {
	struct exfat_chain dir;
	int entry;
	unsigned int type;
	unsigned int start_clu;
	unsigned char flags;
	unsigned short attr;
	loff_t size;
	unsigned int num_subdirs;
	struct timespec64 atime;
	struct timespec64 mtime;
	struct timespec64 crtime;
	struct exfat_dentry_namebuf namebuf;
};

/*
 * exfat mount in-memory data
 */
struct exfat_mount_options {
	kuid_t fs_uid;
	kgid_t fs_gid;
	unsigned short fs_fmask;
	unsigned short fs_dmask;
	/* permission for setting the [am]time */
	unsigned short allow_utime;
	/* charset for filename input/display */
	char *iocharset;
	/* on error: continue, panic, remount-ro */
	enum exfat_error_mode errors;
	unsigned utf8:1, /* Use of UTF-8 character set */
		 sys_tz:1, /* Use local timezone */
		 discard:1, /* Issue discard requests on deletions */
		 keep_last_dots:1; /* Keep trailing periods in paths */
	int time_offset; /* Offset of timestamps from UTC (in minutes) */
};

/*
 * EXFAT file system superblock in-memory data
 */
struct exfat_sb_info {
	unsigned long long num_sectors; /* num of sectors in volume */
	unsigned int num_clusters; /* num of clusters in volume */
	unsigned int cluster_size; /* cluster size in bytes */
	unsigned int cluster_size_bits;
	unsigned int sect_per_clus; /* cluster size in sectors */
	unsigned int sect_per_clus_bits;
	unsigned long long FAT1_start_sector; /* FAT1 start sector */
	unsigned long long FAT2_start_sector; /* FAT2 start sector */
	unsigned long long data_start_sector; /* data area start sector */
	unsigned int num_FAT_sectors; /* num of FAT sectors */
	unsigned int root_dir; /* root dir cluster */
	unsigned int dentries_per_clu; /* num of dentries per cluster */
	unsigned int vol_flags; /* volume flags */
	unsigned int vol_flags_persistent; /* volume flags to retain */
	struct buffer_head *boot_bh; /* buffer_head of BOOT sector */

	unsigned int map_clu; /* allocation bitmap start cluster */
	unsigned int map_sectors; /* num of allocation bitmap sectors */
	struct buffer_head **vol_amap; /* allocation bitmap */

	unsigned short *vol_utbl; /* upcase table */

	unsigned int clu_srch_ptr; /* cluster search pointer */
	unsigned int used_clusters; /* number of used clusters */

	struct mutex s_lock; /* superblock lock */
	struct mutex bitmap_lock; /* bitmap lock */
	struct exfat_mount_options options;
	struct nls_table *nls_io; /* Charset used for input and display */
	struct ratelimit_state ratelimit;

	spinlock_t inode_hash_lock;
	struct hlist_head inode_hashtable[EXFAT_HASH_SIZE];

	struct rcu_head rcu;
};

#define EXFAT_CACHE_VALID	0

/*
 * EXFAT file system inode in-memory data
 */
struct exfat_inode_info {
	struct exfat_chain dir;
	int entry;
	unsigned int type;
	unsigned short attr;
	unsigned int start_clu;
	unsigned char flags;
	/*
	 * the copy of low 32bit of i_version to check
	 * the validation of hint_stat.
	 */
	unsigned int version;

	/* hint for cluster last accessed */
	struct exfat_hint hint_bmap;
	/* hint for entry index we try to lookup next time */
	struct exfat_hint hint_stat;
	/* hint for first empty entry */
	struct exfat_hint_femp hint_femp;

	spinlock_t cache_lru_lock;
	struct list_head cache_lru;
	int nr_caches;
	/* for avoiding the race between alloc and free */
	unsigned int cache_valid_id;

	/*
	 * NOTE: i_size_ondisk is 64bits, so must hold ->inode_lock to access.
	 * physically allocated size.
	 */
	loff_t i_size_ondisk;
	/* block-aligned i_size (used in cont_write_begin) */
	loff_t i_size_aligned;
	/* on-disk position of directory entry or 0 */
	loff_t i_pos;
	/* hash by i_location */
	struct hlist_node i_hash_fat;
	/* protect bmap against truncate */
	struct rw_semaphore truncate_lock;
	struct inode vfs_inode;
	/* File creation time */
	struct timespec64 i_crtime;
};

static inline struct exfat_sb_info *EXFAT_SB(struct super_block *sb)
{
	return sb->s_fs_info;
}

static inline struct exfat_inode_info *EXFAT_I(struct inode *inode)
{
	return container_of(inode, struct exfat_inode_info, vfs_inode);
}

/*
 * If ->i_mode can't hold 0222 (i.e. ATTR_RO), we use ->i_attrs to
 * save ATTR_RO instead of ->i_mode.
 *
 * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
 * bit, it's just used as flag for app.
 */
static inline int exfat_mode_can_hold_ro(struct inode *inode)
{
	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);

	if (S_ISDIR(inode->i_mode))
		return 0;

	if ((~sbi->options.fs_fmask) & 0222)
		return 1;
	return 0;
}

/* Convert attribute bits and a mask to the UNIX mode. */
static inline mode_t exfat_make_mode(struct exfat_sb_info *sbi,
		unsigned short attr, mode_t mode)
{
	if ((attr & ATTR_READONLY) && !(attr & ATTR_SUBDIR))
		mode &= ~0222;

	if (attr & ATTR_SUBDIR)
		return (mode & ~sbi->options.fs_dmask) | S_IFDIR;

	return (mode & ~sbi->options.fs_fmask) | S_IFREG;
}

/* Return the FAT attribute byte for this inode */
static inline unsigned short exfat_make_attr(struct inode *inode)
{
	unsigned short attr = EXFAT_I(inode)->attr;

	if (S_ISDIR(inode->i_mode))
		attr |= ATTR_SUBDIR;
	if (exfat_mode_can_hold_ro(inode) && !(inode->i_mode & 0222))
		attr |= ATTR_READONLY;
	return attr;
}

static inline void exfat_save_attr(struct inode *inode, unsigned short attr)
{
	if (exfat_mode_can_hold_ro(inode))
		EXFAT_I(inode)->attr = attr & (ATTR_RWMASK | ATTR_READONLY);
	else
		EXFAT_I(inode)->attr = attr & ATTR_RWMASK;
}

static inline bool exfat_is_last_sector_in_cluster(struct exfat_sb_info *sbi,
		sector_t sec)
{
	return ((sec - sbi->data_start_sector + 1) &
		((1 << sbi->sect_per_clus_bits) - 1)) == 0;
}

static inline sector_t exfat_cluster_to_sector(struct exfat_sb_info *sbi,
		unsigned int clus)
{
	return ((sector_t)(clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits) +
		sbi->data_start_sector;
}

static inline int exfat_sector_to_cluster(struct exfat_sb_info *sbi,
		sector_t sec)
{
	return ((sec - sbi->data_start_sector) >> sbi->sect_per_clus_bits) +
		EXFAT_RESERVED_CLUSTERS;
}

static inline bool is_valid_cluster(struct exfat_sb_info *sbi,
		unsigned int clus)
{
	return clus >= EXFAT_FIRST_CLUSTER && clus < sbi->num_clusters;
}

/* super.c */
int exfat_set_volume_dirty(struct super_block *sb);
int exfat_clear_volume_dirty(struct super_block *sb);

/* fatent.c */
#define exfat_get_next_cluster(sb, pclu) exfat_ent_get(sb, *(pclu), pclu)

int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc,
		struct exfat_chain *p_chain, bool sync_bmap);
int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain);
int exfat_ent_get(struct super_block *sb, unsigned int loc,
		unsigned int *content);
int exfat_ent_set(struct super_block *sb, unsigned int loc,
		unsigned int content);
int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir,
		int entry, struct exfat_dentry *p_entry);
int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain,
		unsigned int len);
int exfat_zeroed_cluster(struct inode *dir, unsigned int clu);
int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain,
		unsigned int *ret_clu);
int exfat_count_num_clusters(struct super_block *sb,
		struct exfat_chain *p_chain, unsigned int *ret_count);

/* balloc.c */
int exfat_load_bitmap(struct super_block *sb);
void exfat_free_bitmap(struct exfat_sb_info *sbi);
int exfat_set_bitmap(struct inode *inode, unsigned int clu, bool sync);
void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync);
unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu);
int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count);
int exfat_trim_fs(struct inode *inode, struct fstrim_range *range);

/* file.c */
extern const struct file_operations exfat_file_operations;
int __exfat_truncate(struct inode *inode, loff_t new_size);
void exfat_truncate(struct inode *inode, loff_t size);
int exfat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
		  struct iattr *attr);
int exfat_getattr(struct user_namespace *mnt_userns, const struct path *path,
		  struct kstat *stat, unsigned int request_mask,
		  unsigned int query_flags);
int exfat_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
long exfat_compat_ioctl(struct file *filp, unsigned int cmd,
				unsigned long arg);

/* namei.c */
extern const struct dentry_operations exfat_dentry_ops;
extern const struct dentry_operations exfat_utf8_dentry_ops;

/* cache.c */
int exfat_cache_init(void);
void exfat_cache_shutdown(void);
void exfat_cache_inval_inode(struct inode *inode);
int exfat_get_cluster(struct inode *inode, unsigned int cluster,
		unsigned int *fclus, unsigned int *dclus,
		unsigned int *last_dclus, int allow_eof);

/* dir.c */
extern const struct inode_operations exfat_dir_inode_operations;
extern const struct file_operations exfat_dir_operations;
unsigned int exfat_get_entry_type(struct exfat_dentry *p_entry);
int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir,
		int entry, unsigned int type, unsigned int start_clu,
		unsigned long long size);
int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir,
		int entry, int num_entries, struct exfat_uni_name *p_uniname);
int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir,
		int entry, int order, int num_entries);
int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
		int entry);
void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es);
int exfat_calc_num_entries(struct exfat_uni_name *p_uniname);
int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei,
		struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
		int num_entries, unsigned int type, struct exfat_hint *hint_opt);
int exfat_alloc_new_dir(struct inode *inode, struct exfat_chain *clu);
struct exfat_dentry *exfat_get_dentry(struct super_block *sb,
		struct exfat_chain *p_dir, int entry, struct buffer_head **bh);
struct exfat_dentry *exfat_get_dentry_cached(struct exfat_entry_set_cache *es,
		int num);
struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
		struct exfat_chain *p_dir, int entry, unsigned int type);
int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync);
int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir);

/* inode.c */
extern const struct inode_operations exfat_file_inode_operations;
void exfat_sync_inode(struct inode *inode);
struct inode *exfat_build_inode(struct super_block *sb,
		struct exfat_dir_entry *info, loff_t i_pos);
void exfat_hash_inode(struct inode *inode, loff_t i_pos);
void exfat_unhash_inode(struct inode *inode);
struct inode *exfat_iget(struct super_block *sb, loff_t i_pos);
int __exfat_write_inode(struct inode *inode, int sync);
int exfat_write_inode(struct inode *inode, struct writeback_control *wbc);
void exfat_evict_inode(struct inode *inode);
int exfat_block_truncate_page(struct inode *inode, loff_t from);

/* exfat/nls.c */
unsigned short exfat_toupper(struct super_block *sb, unsigned short a);
int exfat_uniname_ncmp(struct super_block *sb, unsigned short *a,
		unsigned short *b, unsigned int len);
int exfat_utf16_to_nls(struct super_block *sb,
		struct exfat_uni_name *uniname, unsigned char *p_cstring,
		int len);
int exfat_nls_to_utf16(struct super_block *sb,
		const unsigned char *p_cstring, const int len,
		struct exfat_uni_name *uniname, int *p_lossy);
int exfat_create_upcase_table(struct super_block *sb);
void exfat_free_upcase_table(struct exfat_sb_info *sbi);

/* exfat/misc.c */
void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
		__printf(3, 4) __cold;
#define exfat_fs_error(sb, fmt, args...)          \
		__exfat_fs_error(sb, 1, fmt, ## args)
#define exfat_fs_error_ratelimit(sb, fmt, args...) \
		__exfat_fs_error(sb, __ratelimit(&EXFAT_SB(sb)->ratelimit), \
		fmt, ## args)

/* expand to pr_*() with prefix */
#define exfat_err(sb, fmt, ...)						\
	pr_err("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)
#define exfat_warn(sb, fmt, ...)					\
	pr_warn("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)
#define exfat_info(sb, fmt, ...)					\
	pr_info("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)
#define exfat_debug(sb, fmt, ...)					\
	pr_debug("exFAT-fs (%s): " fmt "\n", (sb)->s_id, ##__VA_ARGS__)

void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
		u8 tz, __le16 time, __le16 date, u8 time_cs);
void exfat_truncate_atime(struct timespec64 *ts);
void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
		u8 *tz, __le16 *time, __le16 *date, u8 *time_cs);
u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type);
u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type);
void exfat_update_bh(struct buffer_head *bh, int sync);
int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync);
void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
		unsigned int size, unsigned char flags);
void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec);

#endif /* !_EXFAT_FS_H */