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_SB_DIRTY 0 17 18 #define EXFAT_CLUSTERS_UNTRACKED (~0u) 19 20 /* 21 * exfat error flags 22 */ 23 enum exfat_error_mode { 24 EXFAT_ERRORS_CONT, /* ignore error and continue */ 25 EXFAT_ERRORS_PANIC, /* panic on error */ 26 EXFAT_ERRORS_RO, /* remount r/o on error */ 27 }; 28 29 /* 30 * exfat nls lossy flag 31 */ 32 enum { 33 NLS_NAME_NO_LOSSY, /* no lossy */ 34 NLS_NAME_LOSSY, /* just detected incorrect filename(s) */ 35 NLS_NAME_OVERLEN, /* the length is over than its limit */ 36 }; 37 38 #define EXFAT_HASH_BITS 8 39 #define EXFAT_HASH_SIZE (1UL << EXFAT_HASH_BITS) 40 41 /* 42 * Type Definitions 43 */ 44 #define ES_2_ENTRIES 2 45 #define ES_ALL_ENTRIES 0 46 47 #define DIR_DELETED 0xFFFF0321 48 49 /* type values */ 50 #define TYPE_UNUSED 0x0000 51 #define TYPE_DELETED 0x0001 52 #define TYPE_INVALID 0x0002 53 #define TYPE_CRITICAL_PRI 0x0100 54 #define TYPE_BITMAP 0x0101 55 #define TYPE_UPCASE 0x0102 56 #define TYPE_VOLUME 0x0103 57 #define TYPE_DIR 0x0104 58 #define TYPE_FILE 0x011F 59 #define TYPE_CRITICAL_SEC 0x0200 60 #define TYPE_STREAM 0x0201 61 #define TYPE_EXTEND 0x0202 62 #define TYPE_ACL 0x0203 63 #define TYPE_BENIGN_PRI 0x0400 64 #define TYPE_GUID 0x0401 65 #define TYPE_PADDING 0x0402 66 #define TYPE_ACLTAB 0x0403 67 #define TYPE_BENIGN_SEC 0x0800 68 #define TYPE_ALL 0x0FFF 69 70 #define MAX_CHARSET_SIZE 6 /* max size of multi-byte character */ 71 #define MAX_NAME_LENGTH 255 /* max len of file name excluding NULL */ 72 #define MAX_VFSNAME_BUF_SIZE ((MAX_NAME_LENGTH + 1) * MAX_CHARSET_SIZE) 73 74 #define FAT_CACHE_SIZE 128 75 #define FAT_CACHE_HASH_SIZE 64 76 #define BUF_CACHE_SIZE 256 77 #define BUF_CACHE_HASH_SIZE 64 78 79 #define EXFAT_HINT_NONE -1 80 #define EXFAT_MIN_SUBDIR 2 81 82 /* 83 * helpers for cluster size to byte conversion. 84 */ 85 #define EXFAT_CLU_TO_B(b, sbi) ((b) << (sbi)->cluster_size_bits) 86 #define EXFAT_B_TO_CLU(b, sbi) ((b) >> (sbi)->cluster_size_bits) 87 #define EXFAT_B_TO_CLU_ROUND_UP(b, sbi) \ 88 (((b - 1) >> (sbi)->cluster_size_bits) + 1) 89 #define EXFAT_CLU_OFFSET(off, sbi) ((off) & ((sbi)->cluster_size - 1)) 90 91 /* 92 * helpers for block size to byte conversion. 93 */ 94 #define EXFAT_BLK_TO_B(b, sb) ((b) << (sb)->s_blocksize_bits) 95 #define EXFAT_B_TO_BLK(b, sb) ((b) >> (sb)->s_blocksize_bits) 96 #define EXFAT_B_TO_BLK_ROUND_UP(b, sb) \ 97 (((b - 1) >> (sb)->s_blocksize_bits) + 1) 98 #define EXFAT_BLK_OFFSET(off, sb) ((off) & ((sb)->s_blocksize - 1)) 99 100 /* 101 * helpers for block size to dentry size conversion. 102 */ 103 #define EXFAT_B_TO_DEN_IDX(b, sbi) \ 104 ((b) << ((sbi)->cluster_size_bits - DENTRY_SIZE_BITS)) 105 #define EXFAT_B_TO_DEN(b) ((b) >> DENTRY_SIZE_BITS) 106 #define EXFAT_DEN_TO_B(b) ((b) << DENTRY_SIZE_BITS) 107 108 /* 109 * helpers for fat entry. 110 */ 111 #define FAT_ENT_SIZE (4) 112 #define FAT_ENT_SIZE_BITS (2) 113 #define FAT_ENT_OFFSET_SECTOR(sb, loc) (EXFAT_SB(sb)->FAT1_start_sector + \ 114 (((u64)loc << FAT_ENT_SIZE_BITS) >> sb->s_blocksize_bits)) 115 #define FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc) \ 116 ((loc << FAT_ENT_SIZE_BITS) & (sb->s_blocksize - 1)) 117 118 /* 119 * helpers for bitmap. 120 */ 121 #define CLUSTER_TO_BITMAP_ENT(clu) ((clu) - EXFAT_RESERVED_CLUSTERS) 122 #define BITMAP_ENT_TO_CLUSTER(ent) ((ent) + EXFAT_RESERVED_CLUSTERS) 123 #define BITS_PER_SECTOR(sb) ((sb)->s_blocksize * BITS_PER_BYTE) 124 #define BITS_PER_SECTOR_MASK(sb) (BITS_PER_SECTOR(sb) - 1) 125 #define BITMAP_OFFSET_SECTOR_INDEX(sb, ent) \ 126 ((ent / BITS_PER_BYTE) >> (sb)->s_blocksize_bits) 127 #define BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent) (ent & BITS_PER_SECTOR_MASK(sb)) 128 #define BITMAP_OFFSET_BYTE_IN_SECTOR(sb, ent) \ 129 ((ent / BITS_PER_BYTE) & ((sb)->s_blocksize - 1)) 130 #define BITS_PER_BYTE_MASK 0x7 131 #define IGNORED_BITS_REMAINED(clu, clu_base) ((1 << ((clu) - (clu_base))) - 1) 132 133 struct exfat_dentry_namebuf { 134 char *lfn; 135 int lfnbuf_len; /* usally MAX_UNINAME_BUF_SIZE */ 136 }; 137 138 /* unicode name structure */ 139 struct exfat_uni_name { 140 /* +3 for null and for converting */ 141 unsigned short name[MAX_NAME_LENGTH + 3]; 142 unsigned short name_hash; 143 unsigned char name_len; 144 }; 145 146 /* directory structure */ 147 struct exfat_chain { 148 unsigned int dir; 149 unsigned int size; 150 unsigned char flags; 151 }; 152 153 /* first empty entry hint information */ 154 struct exfat_hint_femp { 155 /* entry index of a directory */ 156 int eidx; 157 /* count of continuous empty entry */ 158 int count; 159 /* the cluster that first empty slot exists in */ 160 struct exfat_chain cur; 161 }; 162 163 /* hint structure */ 164 struct exfat_hint { 165 unsigned int clu; 166 union { 167 unsigned int off; /* cluster offset */ 168 int eidx; /* entry index */ 169 }; 170 }; 171 172 struct exfat_entry_set_cache { 173 /* sector number that contains file_entry */ 174 sector_t sector; 175 /* byte offset in the sector */ 176 unsigned int offset; 177 /* flag in stream entry. 01 for cluster chain, 03 for contig. */ 178 int alloc_flag; 179 unsigned int num_entries; 180 struct exfat_dentry entries[]; 181 }; 182 183 struct exfat_dir_entry { 184 struct exfat_chain dir; 185 int entry; 186 unsigned int type; 187 unsigned int start_clu; 188 unsigned char flags; 189 unsigned short attr; 190 loff_t size; 191 unsigned int num_subdirs; 192 struct timespec64 atime; 193 struct timespec64 mtime; 194 struct timespec64 crtime; 195 struct exfat_dentry_namebuf namebuf; 196 }; 197 198 /* 199 * exfat mount in-memory data 200 */ 201 struct exfat_mount_options { 202 kuid_t fs_uid; 203 kgid_t fs_gid; 204 unsigned short fs_fmask; 205 unsigned short fs_dmask; 206 /* permission for setting the [am]time */ 207 unsigned short allow_utime; 208 /* charset for filename input/display */ 209 char *iocharset; 210 /* on error: continue, panic, remount-ro */ 211 enum exfat_error_mode errors; 212 unsigned utf8:1, /* Use of UTF-8 character set */ 213 discard:1; /* Issue discard requests on deletions */ 214 int time_offset; /* Offset of timestamps from UTC (in minutes) */ 215 }; 216 217 /* 218 * EXFAT file system superblock in-memory data 219 */ 220 struct exfat_sb_info { 221 unsigned long long num_sectors; /* num of sectors in volume */ 222 unsigned int num_clusters; /* num of clusters in volume */ 223 unsigned int cluster_size; /* cluster size in bytes */ 224 unsigned int cluster_size_bits; 225 unsigned int sect_per_clus; /* cluster size in sectors */ 226 unsigned int sect_per_clus_bits; 227 unsigned long long FAT1_start_sector; /* FAT1 start sector */ 228 unsigned long long FAT2_start_sector; /* FAT2 start sector */ 229 unsigned long long data_start_sector; /* data area start sector */ 230 unsigned int num_FAT_sectors; /* num of FAT sectors */ 231 unsigned int root_dir; /* root dir cluster */ 232 unsigned int dentries_per_clu; /* num of dentries per cluster */ 233 unsigned int vol_flag; /* volume dirty flag */ 234 struct buffer_head *pbr_bh; /* buffer_head of PBR sector */ 235 236 unsigned int map_clu; /* allocation bitmap start cluster */ 237 unsigned int map_sectors; /* num of allocation bitmap sectors */ 238 struct buffer_head **vol_amap; /* allocation bitmap */ 239 240 unsigned short *vol_utbl; /* upcase table */ 241 242 unsigned int clu_srch_ptr; /* cluster search pointer */ 243 unsigned int used_clusters; /* number of used clusters */ 244 245 unsigned long s_state; 246 struct mutex s_lock; /* superblock lock */ 247 struct exfat_mount_options options; 248 struct nls_table *nls_io; /* Charset used for input and display */ 249 struct ratelimit_state ratelimit; 250 251 spinlock_t inode_hash_lock; 252 struct hlist_head inode_hashtable[EXFAT_HASH_SIZE]; 253 254 struct rcu_head rcu; 255 }; 256 257 /* 258 * EXFAT file system inode in-memory data 259 */ 260 struct exfat_inode_info { 261 struct exfat_chain dir; 262 int entry; 263 unsigned int type; 264 unsigned short attr; 265 unsigned int start_clu; 266 unsigned char flags; 267 /* 268 * the copy of low 32bit of i_version to check 269 * the validation of hint_stat. 270 */ 271 unsigned int version; 272 /* file offset or dentry index for readdir */ 273 loff_t rwoffset; 274 275 /* hint for cluster last accessed */ 276 struct exfat_hint hint_bmap; 277 /* hint for entry index we try to lookup next time */ 278 struct exfat_hint hint_stat; 279 /* hint for first empty entry */ 280 struct exfat_hint_femp hint_femp; 281 282 spinlock_t cache_lru_lock; 283 struct list_head cache_lru; 284 int nr_caches; 285 /* for avoiding the race between alloc and free */ 286 unsigned int cache_valid_id; 287 288 /* 289 * NOTE: i_size_ondisk is 64bits, so must hold ->inode_lock to access. 290 * physically allocated size. 291 */ 292 loff_t i_size_ondisk; 293 /* block-aligned i_size (used in cont_write_begin) */ 294 loff_t i_size_aligned; 295 /* on-disk position of directory entry or 0 */ 296 loff_t i_pos; 297 /* hash by i_location */ 298 struct hlist_node i_hash_fat; 299 /* protect bmap against truncate */ 300 struct rw_semaphore truncate_lock; 301 struct inode vfs_inode; 302 /* File creation time */ 303 struct timespec64 i_crtime; 304 }; 305 306 static inline struct exfat_sb_info *EXFAT_SB(struct super_block *sb) 307 { 308 return sb->s_fs_info; 309 } 310 311 static inline struct exfat_inode_info *EXFAT_I(struct inode *inode) 312 { 313 return container_of(inode, struct exfat_inode_info, vfs_inode); 314 } 315 316 /* 317 * If ->i_mode can't hold 0222 (i.e. ATTR_RO), we use ->i_attrs to 318 * save ATTR_RO instead of ->i_mode. 319 * 320 * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only 321 * bit, it's just used as flag for app. 322 */ 323 static inline int exfat_mode_can_hold_ro(struct inode *inode) 324 { 325 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb); 326 327 if (S_ISDIR(inode->i_mode)) 328 return 0; 329 330 if ((~sbi->options.fs_fmask) & 0222) 331 return 1; 332 return 0; 333 } 334 335 /* Convert attribute bits and a mask to the UNIX mode. */ 336 static inline mode_t exfat_make_mode(struct exfat_sb_info *sbi, 337 unsigned short attr, mode_t mode) 338 { 339 if ((attr & ATTR_READONLY) && !(attr & ATTR_SUBDIR)) 340 mode &= ~0222; 341 342 if (attr & ATTR_SUBDIR) 343 return (mode & ~sbi->options.fs_dmask) | S_IFDIR; 344 345 return (mode & ~sbi->options.fs_fmask) | S_IFREG; 346 } 347 348 /* Return the FAT attribute byte for this inode */ 349 static inline unsigned short exfat_make_attr(struct inode *inode) 350 { 351 unsigned short attr = EXFAT_I(inode)->attr; 352 353 if (S_ISDIR(inode->i_mode)) 354 attr |= ATTR_SUBDIR; 355 if (exfat_mode_can_hold_ro(inode) && !(inode->i_mode & 0222)) 356 attr |= ATTR_READONLY; 357 return attr; 358 } 359 360 static inline void exfat_save_attr(struct inode *inode, unsigned short attr) 361 { 362 if (exfat_mode_can_hold_ro(inode)) 363 EXFAT_I(inode)->attr = attr & (ATTR_RWMASK | ATTR_READONLY); 364 else 365 EXFAT_I(inode)->attr = attr & ATTR_RWMASK; 366 } 367 368 static inline bool exfat_is_last_sector_in_cluster(struct exfat_sb_info *sbi, 369 sector_t sec) 370 { 371 return ((sec - sbi->data_start_sector + 1) & 372 ((1 << sbi->sect_per_clus_bits) - 1)) == 0; 373 } 374 375 static inline sector_t exfat_cluster_to_sector(struct exfat_sb_info *sbi, 376 unsigned int clus) 377 { 378 return ((clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits) + 379 sbi->data_start_sector; 380 } 381 382 static inline int exfat_sector_to_cluster(struct exfat_sb_info *sbi, 383 sector_t sec) 384 { 385 return ((sec - sbi->data_start_sector) >> sbi->sect_per_clus_bits) + 386 EXFAT_RESERVED_CLUSTERS; 387 } 388 389 /* super.c */ 390 int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag); 391 392 /* fatent.c */ 393 #define exfat_get_next_cluster(sb, pclu) exfat_ent_get(sb, *(pclu), pclu) 394 395 int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc, 396 struct exfat_chain *p_chain); 397 int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain); 398 int exfat_ent_get(struct super_block *sb, unsigned int loc, 399 unsigned int *content); 400 int exfat_ent_set(struct super_block *sb, unsigned int loc, 401 unsigned int content); 402 int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir, 403 int entry, struct exfat_dentry *p_entry); 404 int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain, 405 unsigned int len); 406 int exfat_zeroed_cluster(struct inode *dir, unsigned int clu); 407 int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain, 408 unsigned int *ret_clu); 409 int exfat_count_num_clusters(struct super_block *sb, 410 struct exfat_chain *p_chain, unsigned int *ret_count); 411 412 /* balloc.c */ 413 int exfat_load_bitmap(struct super_block *sb); 414 void exfat_free_bitmap(struct exfat_sb_info *sbi); 415 int exfat_set_bitmap(struct inode *inode, unsigned int clu); 416 void exfat_clear_bitmap(struct inode *inode, unsigned int clu); 417 unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu); 418 int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count); 419 420 /* file.c */ 421 extern const struct file_operations exfat_file_operations; 422 int __exfat_truncate(struct inode *inode, loff_t new_size); 423 void exfat_truncate(struct inode *inode, loff_t size); 424 int exfat_setattr(struct dentry *dentry, struct iattr *attr); 425 int exfat_getattr(const struct path *path, struct kstat *stat, 426 unsigned int request_mask, unsigned int query_flags); 427 428 /* namei.c */ 429 extern const struct dentry_operations exfat_dentry_ops; 430 extern const struct dentry_operations exfat_utf8_dentry_ops; 431 432 /* cache.c */ 433 int exfat_cache_init(void); 434 void exfat_cache_shutdown(void); 435 void exfat_cache_init_inode(struct inode *inode); 436 void exfat_cache_inval_inode(struct inode *inode); 437 int exfat_get_cluster(struct inode *inode, unsigned int cluster, 438 unsigned int *fclus, unsigned int *dclus, 439 unsigned int *last_dclus, int allow_eof); 440 441 /* dir.c */ 442 extern const struct inode_operations exfat_dir_inode_operations; 443 extern const struct file_operations exfat_dir_operations; 444 unsigned int exfat_get_entry_type(struct exfat_dentry *p_entry); 445 int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir, 446 int entry, unsigned int type, unsigned int start_clu, 447 unsigned long long size); 448 int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir, 449 int entry, int num_entries, struct exfat_uni_name *p_uniname); 450 int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir, 451 int entry, int order, int num_entries); 452 int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir, 453 int entry); 454 int exfat_update_dir_chksum_with_entry_set(struct super_block *sb, 455 struct exfat_entry_set_cache *es, int sync); 456 int exfat_calc_num_entries(struct exfat_uni_name *p_uniname); 457 int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei, 458 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname, 459 int num_entries, unsigned int type); 460 int exfat_alloc_new_dir(struct inode *inode, struct exfat_chain *clu); 461 int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir, 462 int entry, sector_t *sector, int *offset); 463 struct exfat_dentry *exfat_get_dentry(struct super_block *sb, 464 struct exfat_chain *p_dir, int entry, struct buffer_head **bh, 465 sector_t *sector); 466 struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, 467 struct exfat_chain *p_dir, int entry, unsigned int type, 468 struct exfat_dentry **file_ep); 469 int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir); 470 471 /* inode.c */ 472 extern const struct inode_operations exfat_file_inode_operations; 473 void exfat_sync_inode(struct inode *inode); 474 struct inode *exfat_build_inode(struct super_block *sb, 475 struct exfat_dir_entry *info, loff_t i_pos); 476 void exfat_hash_inode(struct inode *inode, loff_t i_pos); 477 void exfat_unhash_inode(struct inode *inode); 478 struct inode *exfat_iget(struct super_block *sb, loff_t i_pos); 479 int exfat_write_inode(struct inode *inode, struct writeback_control *wbc); 480 void exfat_evict_inode(struct inode *inode); 481 int exfat_block_truncate_page(struct inode *inode, loff_t from); 482 483 /* exfat/nls.c */ 484 unsigned short exfat_toupper(struct super_block *sb, unsigned short a); 485 int exfat_uniname_ncmp(struct super_block *sb, unsigned short *a, 486 unsigned short *b, unsigned int len); 487 int exfat_utf16_to_nls(struct super_block *sb, 488 struct exfat_uni_name *uniname, unsigned char *p_cstring, 489 int len); 490 int exfat_nls_to_utf16(struct super_block *sb, 491 const unsigned char *p_cstring, const int len, 492 struct exfat_uni_name *uniname, int *p_lossy); 493 int exfat_create_upcase_table(struct super_block *sb); 494 void exfat_free_upcase_table(struct exfat_sb_info *sbi); 495 unsigned short exfat_high_surrogate(unicode_t u); 496 unsigned short exfat_low_surrogate(unicode_t u); 497 498 /* exfat/misc.c */ 499 void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...) 500 __printf(3, 4) __cold; 501 #define exfat_fs_error(sb, fmt, args...) \ 502 __exfat_fs_error(sb, 1, fmt, ## args) 503 #define exfat_fs_error_ratelimit(sb, fmt, args...) \ 504 __exfat_fs_error(sb, __ratelimit(&EXFAT_SB(sb)->ratelimit), \ 505 fmt, ## args) 506 void exfat_msg(struct super_block *sb, const char *lv, const char *fmt, ...) 507 __printf(3, 4) __cold; 508 void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts, 509 u8 tz, __le16 time, __le16 date, u8 time_ms); 510 void exfat_truncate_atime(struct timespec64 *ts); 511 void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts, 512 u8 *tz, __le16 *time, __le16 *date, u8 *time_ms); 513 unsigned short exfat_calc_chksum_2byte(void *data, int len, 514 unsigned short chksum, int type); 515 void exfat_update_bh(struct super_block *sb, struct buffer_head *bh, int sync); 516 void exfat_chain_set(struct exfat_chain *ec, unsigned int dir, 517 unsigned int size, unsigned char flags); 518 void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec); 519 520 #endif /* !_EXFAT_FS_H */ 521