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 */
21 enum 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 */
30 enum {
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
129 struct exfat_dentry_namebuf {
130 char *lfn;
131 int lfnbuf_len; /* usually MAX_UNINAME_BUF_SIZE */
132 };
133
134 /* unicode name structure */
135 struct 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 */
143 struct exfat_chain {
144 unsigned int dir;
145 unsigned int size;
146 unsigned char flags;
147 };
148
149 /* first empty entry hint information */
150 struct 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 */
160 struct exfat_hint {
161 unsigned int clu;
162 union {
163 unsigned int off; /* cluster offset */
164 int eidx; /* entry index */
165 };
166 };
167
168 struct 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
177 struct 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 */
195 struct 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 */
214 struct 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 mutex bitmap_lock; /* bitmap lock */
242 struct exfat_mount_options options;
243 struct nls_table *nls_io; /* Charset used for input and display */
244 struct ratelimit_state ratelimit;
245
246 spinlock_t inode_hash_lock;
247 struct hlist_head inode_hashtable[EXFAT_HASH_SIZE];
248
249 struct rcu_head rcu;
250 };
251
252 #define EXFAT_CACHE_VALID 0
253
254 /*
255 * EXFAT file system inode in-memory data
256 */
257 struct exfat_inode_info {
258 struct exfat_chain dir;
259 int entry;
260 unsigned int type;
261 unsigned short attr;
262 unsigned int start_clu;
263 unsigned char flags;
264 /*
265 * the copy of low 32bit of i_version to check
266 * the validation of hint_stat.
267 */
268 unsigned int version;
269
270 /* hint for cluster last accessed */
271 struct exfat_hint hint_bmap;
272 /* hint for entry index we try to lookup next time */
273 struct exfat_hint hint_stat;
274 /* hint for first empty entry */
275 struct exfat_hint_femp hint_femp;
276
277 spinlock_t cache_lru_lock;
278 struct list_head cache_lru;
279 int nr_caches;
280 /* for avoiding the race between alloc and free */
281 unsigned int cache_valid_id;
282
283 /*
284 * NOTE: i_size_ondisk is 64bits, so must hold ->inode_lock to access.
285 * physically allocated size.
286 */
287 loff_t i_size_ondisk;
288 /* block-aligned i_size (used in cont_write_begin) */
289 loff_t i_size_aligned;
290 /* on-disk position of directory entry or 0 */
291 loff_t i_pos;
292 /* hash by i_location */
293 struct hlist_node i_hash_fat;
294 /* protect bmap against truncate */
295 struct rw_semaphore truncate_lock;
296 struct inode vfs_inode;
297 /* File creation time */
298 struct timespec64 i_crtime;
299 };
300
EXFAT_SB(struct super_block * sb)301 static inline struct exfat_sb_info *EXFAT_SB(struct super_block *sb)
302 {
303 return sb->s_fs_info;
304 }
305
EXFAT_I(struct inode * inode)306 static inline struct exfat_inode_info *EXFAT_I(struct inode *inode)
307 {
308 return container_of(inode, struct exfat_inode_info, vfs_inode);
309 }
310
311 /*
312 * If ->i_mode can't hold 0222 (i.e. ATTR_RO), we use ->i_attrs to
313 * save ATTR_RO instead of ->i_mode.
314 *
315 * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
316 * bit, it's just used as flag for app.
317 */
exfat_mode_can_hold_ro(struct inode * inode)318 static inline int exfat_mode_can_hold_ro(struct inode *inode)
319 {
320 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
321
322 if (S_ISDIR(inode->i_mode))
323 return 0;
324
325 if ((~sbi->options.fs_fmask) & 0222)
326 return 1;
327 return 0;
328 }
329
330 /* Convert attribute bits and a mask to the UNIX mode. */
exfat_make_mode(struct exfat_sb_info * sbi,unsigned short attr,mode_t mode)331 static inline mode_t exfat_make_mode(struct exfat_sb_info *sbi,
332 unsigned short attr, mode_t mode)
333 {
334 if ((attr & ATTR_READONLY) && !(attr & ATTR_SUBDIR))
335 mode &= ~0222;
336
337 if (attr & ATTR_SUBDIR)
338 return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
339
340 return (mode & ~sbi->options.fs_fmask) | S_IFREG;
341 }
342
343 /* Return the FAT attribute byte for this inode */
exfat_make_attr(struct inode * inode)344 static inline unsigned short exfat_make_attr(struct inode *inode)
345 {
346 unsigned short attr = EXFAT_I(inode)->attr;
347
348 if (S_ISDIR(inode->i_mode))
349 attr |= ATTR_SUBDIR;
350 if (exfat_mode_can_hold_ro(inode) && !(inode->i_mode & 0222))
351 attr |= ATTR_READONLY;
352 return attr;
353 }
354
exfat_save_attr(struct inode * inode,unsigned short attr)355 static inline void exfat_save_attr(struct inode *inode, unsigned short attr)
356 {
357 if (exfat_mode_can_hold_ro(inode))
358 EXFAT_I(inode)->attr = attr & (ATTR_RWMASK | ATTR_READONLY);
359 else
360 EXFAT_I(inode)->attr = attr & ATTR_RWMASK;
361 }
362
exfat_is_last_sector_in_cluster(struct exfat_sb_info * sbi,sector_t sec)363 static inline bool exfat_is_last_sector_in_cluster(struct exfat_sb_info *sbi,
364 sector_t sec)
365 {
366 return ((sec - sbi->data_start_sector + 1) &
367 ((1 << sbi->sect_per_clus_bits) - 1)) == 0;
368 }
369
exfat_cluster_to_sector(struct exfat_sb_info * sbi,unsigned int clus)370 static inline sector_t exfat_cluster_to_sector(struct exfat_sb_info *sbi,
371 unsigned int clus)
372 {
373 return ((sector_t)(clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits) +
374 sbi->data_start_sector;
375 }
376
exfat_sector_to_cluster(struct exfat_sb_info * sbi,sector_t sec)377 static inline int exfat_sector_to_cluster(struct exfat_sb_info *sbi,
378 sector_t sec)
379 {
380 return ((sec - sbi->data_start_sector) >> sbi->sect_per_clus_bits) +
381 EXFAT_RESERVED_CLUSTERS;
382 }
383
384 /* super.c */
385 int exfat_set_volume_dirty(struct super_block *sb);
386 int exfat_clear_volume_dirty(struct super_block *sb);
387
388 /* fatent.c */
389 #define exfat_get_next_cluster(sb, pclu) exfat_ent_get(sb, *(pclu), pclu)
390
391 int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc,
392 struct exfat_chain *p_chain, bool sync_bmap);
393 int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain);
394 int exfat_ent_get(struct super_block *sb, unsigned int loc,
395 unsigned int *content);
396 int exfat_ent_set(struct super_block *sb, unsigned int loc,
397 unsigned int content);
398 int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir,
399 int entry, struct exfat_dentry *p_entry);
400 int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain,
401 unsigned int len);
402 int exfat_zeroed_cluster(struct inode *dir, unsigned int clu);
403 int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain,
404 unsigned int *ret_clu);
405 int exfat_count_num_clusters(struct super_block *sb,
406 struct exfat_chain *p_chain, unsigned int *ret_count);
407
408 /* balloc.c */
409 int exfat_load_bitmap(struct super_block *sb);
410 void exfat_free_bitmap(struct exfat_sb_info *sbi);
411 int exfat_set_bitmap(struct inode *inode, unsigned int clu, bool sync);
412 void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync);
413 unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu);
414 int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count);
415 int exfat_trim_fs(struct inode *inode, struct fstrim_range *range);
416
417 /* file.c */
418 extern const struct file_operations exfat_file_operations;
419 int __exfat_truncate(struct inode *inode, loff_t new_size);
420 void exfat_truncate(struct inode *inode, loff_t size);
421 int exfat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
422 struct iattr *attr);
423 int exfat_getattr(struct user_namespace *mnt_userns, const struct path *path,
424 struct kstat *stat, unsigned int request_mask,
425 unsigned int query_flags);
426 int exfat_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
427 long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
428 long exfat_compat_ioctl(struct file *filp, unsigned int cmd,
429 unsigned long arg);
430
431 /* namei.c */
432 extern const struct dentry_operations exfat_dentry_ops;
433 extern const struct dentry_operations exfat_utf8_dentry_ops;
434
435 /* cache.c */
436 int exfat_cache_init(void);
437 void exfat_cache_shutdown(void);
438 void exfat_cache_inval_inode(struct inode *inode);
439 int exfat_get_cluster(struct inode *inode, unsigned int cluster,
440 unsigned int *fclus, unsigned int *dclus,
441 unsigned int *last_dclus, int allow_eof);
442
443 /* dir.c */
444 extern const struct inode_operations exfat_dir_inode_operations;
445 extern const struct file_operations exfat_dir_operations;
446 unsigned int exfat_get_entry_type(struct exfat_dentry *p_entry);
447 int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir,
448 int entry, unsigned int type, unsigned int start_clu,
449 unsigned long long size);
450 int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir,
451 int entry, int num_entries, struct exfat_uni_name *p_uniname);
452 int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir,
453 int entry, int order, int num_entries);
454 int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
455 int entry);
456 void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es);
457 int exfat_calc_num_entries(struct exfat_uni_name *p_uniname);
458 int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei,
459 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
460 int num_entries, unsigned int type, struct exfat_hint *hint_opt);
461 int exfat_alloc_new_dir(struct inode *inode, struct exfat_chain *clu);
462 int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir,
463 int entry, sector_t *sector, int *offset);
464 struct exfat_dentry *exfat_get_dentry(struct super_block *sb,
465 struct exfat_chain *p_dir, int entry, struct buffer_head **bh,
466 sector_t *sector);
467 struct exfat_dentry *exfat_get_dentry_cached(struct exfat_entry_set_cache *es,
468 int num);
469 struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
470 struct exfat_chain *p_dir, int entry, unsigned int type);
471 int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync);
472 int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir);
473
474 /* inode.c */
475 extern const struct inode_operations exfat_file_inode_operations;
476 void exfat_sync_inode(struct inode *inode);
477 struct inode *exfat_build_inode(struct super_block *sb,
478 struct exfat_dir_entry *info, loff_t i_pos);
479 void exfat_hash_inode(struct inode *inode, loff_t i_pos);
480 void exfat_unhash_inode(struct inode *inode);
481 struct inode *exfat_iget(struct super_block *sb, loff_t i_pos);
482 int exfat_write_inode(struct inode *inode, struct writeback_control *wbc);
483 void exfat_evict_inode(struct inode *inode);
484 int exfat_block_truncate_page(struct inode *inode, loff_t from);
485
486 /* exfat/nls.c */
487 unsigned short exfat_toupper(struct super_block *sb, unsigned short a);
488 int exfat_uniname_ncmp(struct super_block *sb, unsigned short *a,
489 unsigned short *b, unsigned int len);
490 int exfat_utf16_to_nls(struct super_block *sb,
491 struct exfat_uni_name *uniname, unsigned char *p_cstring,
492 int len);
493 int exfat_nls_to_utf16(struct super_block *sb,
494 const unsigned char *p_cstring, const int len,
495 struct exfat_uni_name *uniname, int *p_lossy);
496 int exfat_create_upcase_table(struct super_block *sb);
497 void exfat_free_upcase_table(struct exfat_sb_info *sbi);
498
499 /* exfat/misc.c */
500 void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
501 __printf(3, 4) __cold;
502 #define exfat_fs_error(sb, fmt, args...) \
503 __exfat_fs_error(sb, 1, fmt, ## args)
504 #define exfat_fs_error_ratelimit(sb, fmt, args...) \
505 __exfat_fs_error(sb, __ratelimit(&EXFAT_SB(sb)->ratelimit), \
506 fmt, ## args)
507 void exfat_msg(struct super_block *sb, const char *lv, const char *fmt, ...)
508 __printf(3, 4) __cold;
509 #define exfat_err(sb, fmt, ...) \
510 exfat_msg(sb, KERN_ERR, fmt, ##__VA_ARGS__)
511 #define exfat_warn(sb, fmt, ...) \
512 exfat_msg(sb, KERN_WARNING, fmt, ##__VA_ARGS__)
513 #define exfat_info(sb, fmt, ...) \
514 exfat_msg(sb, KERN_INFO, fmt, ##__VA_ARGS__)
515
516 void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
517 u8 tz, __le16 time, __le16 date, u8 time_cs);
518 void exfat_truncate_atime(struct timespec64 *ts);
519 void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
520 u8 *tz, __le16 *time, __le16 *date, u8 *time_cs);
521 u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type);
522 u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type);
523 void exfat_update_bh(struct buffer_head *bh, int sync);
524 int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync);
525 void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
526 unsigned int size, unsigned char flags);
527 void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec);
528
529 #endif /* !_EXFAT_FS_H */
530
