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Linux kernel mirror (for testing)
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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#ifndef _EXFAT_FS_H
7#define _EXFAT_FS_H
8
9#include <linux/fs.h>
10#include <linux/ratelimit.h>
11#include <linux/nls.h>
12
13#define EXFAT_SUPER_MAGIC 0x2011BAB0UL
14#define EXFAT_ROOT_INO 1
15
16#define EXFAT_CLUSTERS_UNTRACKED (~0u)
17
18/*
19 * exfat error flags
20 */
21enum exfat_error_mode {
22 EXFAT_ERRORS_CONT, /* ignore error and continue */
23 EXFAT_ERRORS_PANIC, /* panic on error */
24 EXFAT_ERRORS_RO, /* remount r/o on error */
25};
26
27/*
28 * exfat nls lossy flag
29 */
30enum {
31 NLS_NAME_NO_LOSSY, /* no lossy */
32 NLS_NAME_LOSSY, /* just detected incorrect filename(s) */
33 NLS_NAME_OVERLEN, /* the length is over than its limit */
34};
35
36#define EXFAT_HASH_BITS 8
37#define EXFAT_HASH_SIZE (1UL << EXFAT_HASH_BITS)
38
39/*
40 * Type Definitions
41 */
42#define ES_2_ENTRIES 2
43#define ES_ALL_ENTRIES 0
44
45#define DIR_DELETED 0xFFFF0321
46
47/* type values */
48#define TYPE_UNUSED 0x0000
49#define TYPE_DELETED 0x0001
50#define TYPE_INVALID 0x0002
51#define TYPE_CRITICAL_PRI 0x0100
52#define TYPE_BITMAP 0x0101
53#define TYPE_UPCASE 0x0102
54#define TYPE_VOLUME 0x0103
55#define TYPE_DIR 0x0104
56#define TYPE_FILE 0x011F
57#define TYPE_CRITICAL_SEC 0x0200
58#define TYPE_STREAM 0x0201
59#define TYPE_EXTEND 0x0202
60#define TYPE_ACL 0x0203
61#define TYPE_BENIGN_PRI 0x0400
62#define TYPE_GUID 0x0401
63#define TYPE_PADDING 0x0402
64#define TYPE_ACLTAB 0x0403
65#define TYPE_BENIGN_SEC 0x0800
66#define TYPE_ALL 0x0FFF
67
68#define MAX_CHARSET_SIZE 6 /* max size of multi-byte character */
69#define MAX_NAME_LENGTH 255 /* max len of file name excluding NULL */
70#define MAX_VFSNAME_BUF_SIZE ((MAX_NAME_LENGTH + 1) * MAX_CHARSET_SIZE)
71
72/* Enough size to hold 256 dentry (even 512 Byte sector) */
73#define DIR_CACHE_SIZE (256*sizeof(struct exfat_dentry)/512+1)
74
75#define EXFAT_HINT_NONE -1
76#define EXFAT_MIN_SUBDIR 2
77
78/*
79 * helpers for cluster size to byte conversion.
80 */
81#define EXFAT_CLU_TO_B(b, sbi) ((b) << (sbi)->cluster_size_bits)
82#define EXFAT_B_TO_CLU(b, sbi) ((b) >> (sbi)->cluster_size_bits)
83#define EXFAT_B_TO_CLU_ROUND_UP(b, sbi) \
84 (((b - 1) >> (sbi)->cluster_size_bits) + 1)
85#define EXFAT_CLU_OFFSET(off, sbi) ((off) & ((sbi)->cluster_size - 1))
86
87/*
88 * helpers for block size to byte conversion.
89 */
90#define EXFAT_BLK_TO_B(b, sb) ((b) << (sb)->s_blocksize_bits)
91#define EXFAT_B_TO_BLK(b, sb) ((b) >> (sb)->s_blocksize_bits)
92#define EXFAT_B_TO_BLK_ROUND_UP(b, sb) \
93 (((b - 1) >> (sb)->s_blocksize_bits) + 1)
94#define EXFAT_BLK_OFFSET(off, sb) ((off) & ((sb)->s_blocksize - 1))
95
96/*
97 * helpers for block size to dentry size conversion.
98 */
99#define EXFAT_B_TO_DEN_IDX(b, sbi) \
100 ((b) << ((sbi)->cluster_size_bits - DENTRY_SIZE_BITS))
101#define EXFAT_B_TO_DEN(b) ((b) >> DENTRY_SIZE_BITS)
102#define EXFAT_DEN_TO_B(b) ((b) << DENTRY_SIZE_BITS)
103
104/*
105 * helpers for fat entry.
106 */
107#define FAT_ENT_SIZE (4)
108#define FAT_ENT_SIZE_BITS (2)
109#define FAT_ENT_OFFSET_SECTOR(sb, loc) (EXFAT_SB(sb)->FAT1_start_sector + \
110 (((u64)loc << FAT_ENT_SIZE_BITS) >> sb->s_blocksize_bits))
111#define FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc) \
112 ((loc << FAT_ENT_SIZE_BITS) & (sb->s_blocksize - 1))
113
114/*
115 * helpers for bitmap.
116 */
117#define CLUSTER_TO_BITMAP_ENT(clu) ((clu) - EXFAT_RESERVED_CLUSTERS)
118#define BITMAP_ENT_TO_CLUSTER(ent) ((ent) + EXFAT_RESERVED_CLUSTERS)
119#define BITS_PER_SECTOR(sb) ((sb)->s_blocksize * BITS_PER_BYTE)
120#define BITS_PER_SECTOR_MASK(sb) (BITS_PER_SECTOR(sb) - 1)
121#define BITMAP_OFFSET_SECTOR_INDEX(sb, ent) \
122 ((ent / BITS_PER_BYTE) >> (sb)->s_blocksize_bits)
123#define BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent) (ent & BITS_PER_SECTOR_MASK(sb))
124#define BITMAP_OFFSET_BYTE_IN_SECTOR(sb, ent) \
125 ((ent / BITS_PER_BYTE) & ((sb)->s_blocksize - 1))
126#define BITS_PER_BYTE_MASK 0x7
127#define IGNORED_BITS_REMAINED(clu, clu_base) ((1 << ((clu) - (clu_base))) - 1)
128
129struct exfat_dentry_namebuf {
130 char *lfn;
131 int lfnbuf_len; /* usually MAX_UNINAME_BUF_SIZE */
132};
133
134/* unicode name structure */
135struct exfat_uni_name {
136 /* +3 for null and for converting */
137 unsigned short name[MAX_NAME_LENGTH + 3];
138 u16 name_hash;
139 unsigned char name_len;
140};
141
142/* directory structure */
143struct exfat_chain {
144 unsigned int dir;
145 unsigned int size;
146 unsigned char flags;
147};
148
149/* first empty entry hint information */
150struct exfat_hint_femp {
151 /* entry index of a directory */
152 int eidx;
153 /* count of continuous empty entry */
154 int count;
155 /* the cluster that first empty slot exists in */
156 struct exfat_chain cur;
157};
158
159/* hint structure */
160struct exfat_hint {
161 unsigned int clu;
162 union {
163 unsigned int off; /* cluster offset */
164 int eidx; /* entry index */
165 };
166};
167
168struct exfat_entry_set_cache {
169 struct super_block *sb;
170 bool modified;
171 unsigned int start_off;
172 int num_bh;
173 struct buffer_head *bh[DIR_CACHE_SIZE];
174 unsigned int num_entries;
175};
176
177struct exfat_dir_entry {
178 struct exfat_chain dir;
179 int entry;
180 unsigned int type;
181 unsigned int start_clu;
182 unsigned char flags;
183 unsigned short attr;
184 loff_t size;
185 unsigned int num_subdirs;
186 struct timespec64 atime;
187 struct timespec64 mtime;
188 struct timespec64 crtime;
189 struct exfat_dentry_namebuf namebuf;
190};
191
192/*
193 * exfat mount in-memory data
194 */
195struct exfat_mount_options {
196 kuid_t fs_uid;
197 kgid_t fs_gid;
198 unsigned short fs_fmask;
199 unsigned short fs_dmask;
200 /* permission for setting the [am]time */
201 unsigned short allow_utime;
202 /* charset for filename input/display */
203 char *iocharset;
204 /* on error: continue, panic, remount-ro */
205 enum exfat_error_mode errors;
206 unsigned utf8:1, /* Use of UTF-8 character set */
207 discard:1; /* Issue discard requests on deletions */
208 int time_offset; /* Offset of timestamps from UTC (in minutes) */
209};
210
211/*
212 * EXFAT file system superblock in-memory data
213 */
214struct exfat_sb_info {
215 unsigned long long num_sectors; /* num of sectors in volume */
216 unsigned int num_clusters; /* num of clusters in volume */
217 unsigned int cluster_size; /* cluster size in bytes */
218 unsigned int cluster_size_bits;
219 unsigned int sect_per_clus; /* cluster size in sectors */
220 unsigned int sect_per_clus_bits;
221 unsigned long long FAT1_start_sector; /* FAT1 start sector */
222 unsigned long long FAT2_start_sector; /* FAT2 start sector */
223 unsigned long long data_start_sector; /* data area start sector */
224 unsigned int num_FAT_sectors; /* num of FAT sectors */
225 unsigned int root_dir; /* root dir cluster */
226 unsigned int dentries_per_clu; /* num of dentries per cluster */
227 unsigned int vol_flags; /* volume flags */
228 unsigned int vol_flags_persistent; /* volume flags to retain */
229 struct buffer_head *boot_bh; /* buffer_head of BOOT sector */
230
231 unsigned int map_clu; /* allocation bitmap start cluster */
232 unsigned int map_sectors; /* num of allocation bitmap sectors */
233 struct buffer_head **vol_amap; /* allocation bitmap */
234
235 unsigned short *vol_utbl; /* upcase table */
236
237 unsigned int clu_srch_ptr; /* cluster search pointer */
238 unsigned int used_clusters; /* number of used clusters */
239
240 struct mutex s_lock; /* superblock lock */
241 struct exfat_mount_options options;
242 struct nls_table *nls_io; /* Charset used for input and display */
243 struct ratelimit_state ratelimit;
244
245 spinlock_t inode_hash_lock;
246 struct hlist_head inode_hashtable[EXFAT_HASH_SIZE];
247
248 struct rcu_head rcu;
249};
250
251#define EXFAT_CACHE_VALID 0
252
253/*
254 * EXFAT file system inode in-memory data
255 */
256struct exfat_inode_info {
257 struct exfat_chain dir;
258 int entry;
259 unsigned int type;
260 unsigned short attr;
261 unsigned int start_clu;
262 unsigned char flags;
263 /*
264 * the copy of low 32bit of i_version to check
265 * the validation of hint_stat.
266 */
267 unsigned int version;
268
269 /* hint for cluster last accessed */
270 struct exfat_hint hint_bmap;
271 /* hint for entry index we try to lookup next time */
272 struct exfat_hint hint_stat;
273 /* hint for first empty entry */
274 struct exfat_hint_femp hint_femp;
275
276 spinlock_t cache_lru_lock;
277 struct list_head cache_lru;
278 int nr_caches;
279 /* for avoiding the race between alloc and free */
280 unsigned int cache_valid_id;
281
282 /*
283 * NOTE: i_size_ondisk is 64bits, so must hold ->inode_lock to access.
284 * physically allocated size.
285 */
286 loff_t i_size_ondisk;
287 /* block-aligned i_size (used in cont_write_begin) */
288 loff_t i_size_aligned;
289 /* on-disk position of directory entry or 0 */
290 loff_t i_pos;
291 /* hash by i_location */
292 struct hlist_node i_hash_fat;
293 /* protect bmap against truncate */
294 struct rw_semaphore truncate_lock;
295 struct inode vfs_inode;
296 /* File creation time */
297 struct timespec64 i_crtime;
298};
299
300static inline struct exfat_sb_info *EXFAT_SB(struct super_block *sb)
301{
302 return sb->s_fs_info;
303}
304
305static inline struct exfat_inode_info *EXFAT_I(struct inode *inode)
306{
307 return container_of(inode, struct exfat_inode_info, vfs_inode);
308}
309
310/*
311 * If ->i_mode can't hold 0222 (i.e. ATTR_RO), we use ->i_attrs to
312 * save ATTR_RO instead of ->i_mode.
313 *
314 * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
315 * bit, it's just used as flag for app.
316 */
317static inline int exfat_mode_can_hold_ro(struct inode *inode)
318{
319 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
320
321 if (S_ISDIR(inode->i_mode))
322 return 0;
323
324 if ((~sbi->options.fs_fmask) & 0222)
325 return 1;
326 return 0;
327}
328
329/* Convert attribute bits and a mask to the UNIX mode. */
330static inline mode_t exfat_make_mode(struct exfat_sb_info *sbi,
331 unsigned short attr, mode_t mode)
332{
333 if ((attr & ATTR_READONLY) && !(attr & ATTR_SUBDIR))
334 mode &= ~0222;
335
336 if (attr & ATTR_SUBDIR)
337 return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
338
339 return (mode & ~sbi->options.fs_fmask) | S_IFREG;
340}
341
342/* Return the FAT attribute byte for this inode */
343static inline unsigned short exfat_make_attr(struct inode *inode)
344{
345 unsigned short attr = EXFAT_I(inode)->attr;
346
347 if (S_ISDIR(inode->i_mode))
348 attr |= ATTR_SUBDIR;
349 if (exfat_mode_can_hold_ro(inode) && !(inode->i_mode & 0222))
350 attr |= ATTR_READONLY;
351 return attr;
352}
353
354static inline void exfat_save_attr(struct inode *inode, unsigned short attr)
355{
356 if (exfat_mode_can_hold_ro(inode))
357 EXFAT_I(inode)->attr = attr & (ATTR_RWMASK | ATTR_READONLY);
358 else
359 EXFAT_I(inode)->attr = attr & ATTR_RWMASK;
360}
361
362static inline bool exfat_is_last_sector_in_cluster(struct exfat_sb_info *sbi,
363 sector_t sec)
364{
365 return ((sec - sbi->data_start_sector + 1) &
366 ((1 << sbi->sect_per_clus_bits) - 1)) == 0;
367}
368
369static inline sector_t exfat_cluster_to_sector(struct exfat_sb_info *sbi,
370 unsigned int clus)
371{
372 return ((sector_t)(clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits) +
373 sbi->data_start_sector;
374}
375
376static inline int exfat_sector_to_cluster(struct exfat_sb_info *sbi,
377 sector_t sec)
378{
379 return ((sec - sbi->data_start_sector) >> sbi->sect_per_clus_bits) +
380 EXFAT_RESERVED_CLUSTERS;
381}
382
383/* super.c */
384int exfat_set_volume_dirty(struct super_block *sb);
385int exfat_clear_volume_dirty(struct super_block *sb);
386
387/* fatent.c */
388#define exfat_get_next_cluster(sb, pclu) exfat_ent_get(sb, *(pclu), pclu)
389
390int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc,
391 struct exfat_chain *p_chain);
392int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain);
393int exfat_ent_get(struct super_block *sb, unsigned int loc,
394 unsigned int *content);
395int exfat_ent_set(struct super_block *sb, unsigned int loc,
396 unsigned int content);
397int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir,
398 int entry, struct exfat_dentry *p_entry);
399int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain,
400 unsigned int len);
401int exfat_zeroed_cluster(struct inode *dir, unsigned int clu);
402int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain,
403 unsigned int *ret_clu);
404int exfat_count_num_clusters(struct super_block *sb,
405 struct exfat_chain *p_chain, unsigned int *ret_count);
406
407/* balloc.c */
408int exfat_load_bitmap(struct super_block *sb);
409void exfat_free_bitmap(struct exfat_sb_info *sbi);
410int exfat_set_bitmap(struct inode *inode, unsigned int clu);
411void exfat_clear_bitmap(struct inode *inode, unsigned int clu);
412unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu);
413int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count);
414
415/* file.c */
416extern const struct file_operations exfat_file_operations;
417int __exfat_truncate(struct inode *inode, loff_t new_size);
418void exfat_truncate(struct inode *inode, loff_t size);
419int exfat_setattr(struct dentry *dentry, struct iattr *attr);
420int exfat_getattr(const struct path *path, struct kstat *stat,
421 unsigned int request_mask, unsigned int query_flags);
422int exfat_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
423
424/* namei.c */
425extern const struct dentry_operations exfat_dentry_ops;
426extern const struct dentry_operations exfat_utf8_dentry_ops;
427
428/* cache.c */
429int exfat_cache_init(void);
430void exfat_cache_shutdown(void);
431void exfat_cache_inval_inode(struct inode *inode);
432int exfat_get_cluster(struct inode *inode, unsigned int cluster,
433 unsigned int *fclus, unsigned int *dclus,
434 unsigned int *last_dclus, int allow_eof);
435
436/* dir.c */
437extern const struct inode_operations exfat_dir_inode_operations;
438extern const struct file_operations exfat_dir_operations;
439unsigned int exfat_get_entry_type(struct exfat_dentry *p_entry);
440int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir,
441 int entry, unsigned int type, unsigned int start_clu,
442 unsigned long long size);
443int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir,
444 int entry, int num_entries, struct exfat_uni_name *p_uniname);
445int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir,
446 int entry, int order, int num_entries);
447int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
448 int entry);
449void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es);
450int exfat_calc_num_entries(struct exfat_uni_name *p_uniname);
451int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei,
452 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
453 int num_entries, unsigned int type);
454int exfat_alloc_new_dir(struct inode *inode, struct exfat_chain *clu);
455int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir,
456 int entry, sector_t *sector, int *offset);
457struct exfat_dentry *exfat_get_dentry(struct super_block *sb,
458 struct exfat_chain *p_dir, int entry, struct buffer_head **bh,
459 sector_t *sector);
460struct exfat_dentry *exfat_get_dentry_cached(struct exfat_entry_set_cache *es,
461 int num);
462struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
463 struct exfat_chain *p_dir, int entry, unsigned int type);
464int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync);
465int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir);
466
467/* inode.c */
468extern const struct inode_operations exfat_file_inode_operations;
469void exfat_sync_inode(struct inode *inode);
470struct inode *exfat_build_inode(struct super_block *sb,
471 struct exfat_dir_entry *info, loff_t i_pos);
472void exfat_hash_inode(struct inode *inode, loff_t i_pos);
473void exfat_unhash_inode(struct inode *inode);
474struct inode *exfat_iget(struct super_block *sb, loff_t i_pos);
475int exfat_write_inode(struct inode *inode, struct writeback_control *wbc);
476void exfat_evict_inode(struct inode *inode);
477int exfat_block_truncate_page(struct inode *inode, loff_t from);
478
479/* exfat/nls.c */
480unsigned short exfat_toupper(struct super_block *sb, unsigned short a);
481int exfat_uniname_ncmp(struct super_block *sb, unsigned short *a,
482 unsigned short *b, unsigned int len);
483int exfat_utf16_to_nls(struct super_block *sb,
484 struct exfat_uni_name *uniname, unsigned char *p_cstring,
485 int len);
486int exfat_nls_to_utf16(struct super_block *sb,
487 const unsigned char *p_cstring, const int len,
488 struct exfat_uni_name *uniname, int *p_lossy);
489int exfat_create_upcase_table(struct super_block *sb);
490void exfat_free_upcase_table(struct exfat_sb_info *sbi);
491
492/* exfat/misc.c */
493void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
494 __printf(3, 4) __cold;
495#define exfat_fs_error(sb, fmt, args...) \
496 __exfat_fs_error(sb, 1, fmt, ## args)
497#define exfat_fs_error_ratelimit(sb, fmt, args...) \
498 __exfat_fs_error(sb, __ratelimit(&EXFAT_SB(sb)->ratelimit), \
499 fmt, ## args)
500void exfat_msg(struct super_block *sb, const char *lv, const char *fmt, ...)
501 __printf(3, 4) __cold;
502#define exfat_err(sb, fmt, ...) \
503 exfat_msg(sb, KERN_ERR, fmt, ##__VA_ARGS__)
504#define exfat_warn(sb, fmt, ...) \
505 exfat_msg(sb, KERN_WARNING, fmt, ##__VA_ARGS__)
506#define exfat_info(sb, fmt, ...) \
507 exfat_msg(sb, KERN_INFO, fmt, ##__VA_ARGS__)
508
509void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
510 u8 tz, __le16 time, __le16 date, u8 time_cs);
511void exfat_truncate_atime(struct timespec64 *ts);
512void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
513 u8 *tz, __le16 *time, __le16 *date, u8 *time_cs);
514u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type);
515u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type);
516void exfat_update_bh(struct buffer_head *bh, int sync);
517int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync);
518void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
519 unsigned int size, unsigned char flags);
520void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec);
521
522#endif /* !_EXFAT_FS_H */