1 #ifndef _LINUX_MSDOS_FS_H 2 #define _LINUX_MSDOS_FS_H 3 4 #include <linux/magic.h> 5 #include <asm/byteorder.h> 6 7 /* 8 * The MS-DOS filesystem constants/structures 9 */ 10 11 #define SECTOR_SIZE 512 /* sector size (bytes) */ 12 #define SECTOR_BITS 9 /* log2(SECTOR_SIZE) */ 13 #define MSDOS_DPB (MSDOS_DPS) /* dir entries per block */ 14 #define MSDOS_DPB_BITS 4 /* log2(MSDOS_DPB) */ 15 #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) 16 #define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */ 17 #define CF_LE_W(v) le16_to_cpu(v) 18 #define CF_LE_L(v) le32_to_cpu(v) 19 #define CT_LE_W(v) cpu_to_le16(v) 20 #define CT_LE_L(v) cpu_to_le32(v) 21 22 23 #define MSDOS_ROOT_INO 1 /* == MINIX_ROOT_INO */ 24 #define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */ 25 26 /* directory limit */ 27 #define FAT_MAX_DIR_ENTRIES (65536) 28 #define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS) 29 30 #define ATTR_NONE 0 /* no attribute bits */ 31 #define ATTR_RO 1 /* read-only */ 32 #define ATTR_HIDDEN 2 /* hidden */ 33 #define ATTR_SYS 4 /* system */ 34 #define ATTR_VOLUME 8 /* volume label */ 35 #define ATTR_DIR 16 /* directory */ 36 #define ATTR_ARCH 32 /* archived */ 37 38 /* attribute bits that are copied "as is" */ 39 #define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN) 40 /* bits that are used by the Windows 95/Windows NT extended FAT */ 41 #define ATTR_EXT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME) 42 43 #define CASE_LOWER_BASE 8 /* base is lower case */ 44 #define CASE_LOWER_EXT 16 /* extension is lower case */ 45 46 #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */ 47 #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG) 48 49 /* valid file mode bits */ 50 #define MSDOS_VALID_MODE (S_IFREG | S_IFDIR | S_IRWXU | S_IRWXG | S_IRWXO) 51 /* Convert attribute bits and a mask to the UNIX mode. */ 52 #define MSDOS_MKMODE(a, m) (m & (a & ATTR_RO ? S_IRUGO|S_IXUGO : S_IRWXUGO)) 53 54 #define MSDOS_NAME 11 /* maximum name length */ 55 #define MSDOS_LONGNAME 256 /* maximum name length */ 56 #define MSDOS_SLOTS 21 /* max # of slots for short and long names */ 57 #define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */ 58 #define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */ 59 60 #define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \ 61 MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x)) 62 63 /* start of data cluster's entry (number of reserved clusters) */ 64 #define FAT_START_ENT 2 65 66 /* maximum number of clusters */ 67 #define MAX_FAT12 0xFF4 68 #define MAX_FAT16 0xFFF4 69 #define MAX_FAT32 0x0FFFFFF6 70 #define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \ 71 MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12) 72 73 /* bad cluster mark */ 74 #define BAD_FAT12 0xFF7 75 #define BAD_FAT16 0xFFF7 76 #define BAD_FAT32 0x0FFFFFF7 77 78 /* standard EOF */ 79 #define EOF_FAT12 0xFFF 80 #define EOF_FAT16 0xFFFF 81 #define EOF_FAT32 0x0FFFFFFF 82 83 #define FAT_ENT_FREE (0) 84 #define FAT_ENT_BAD (BAD_FAT32) 85 #define FAT_ENT_EOF (EOF_FAT32) 86 87 #define FAT_FSINFO_SIG1 0x41615252 88 #define FAT_FSINFO_SIG2 0x61417272 89 #define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \ 90 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2) 91 92 struct __fat_dirent { 93 long d_ino; 94 __kernel_off_t d_off; 95 unsigned short d_reclen; 96 char d_name[256]; /* We must not include limits.h! */ 97 }; 98 99 /* 100 * ioctl commands 101 */ 102 #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct __fat_dirent[2]) 103 #define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct __fat_dirent[2]) 104 /* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */ 105 #define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32) 106 #define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32) 107 108 struct fat_boot_sector { 109 __u8 ignored[3]; /* Boot strap short or near jump */ 110 __u8 system_id[8]; /* Name - can be used to special case 111 partition manager volumes */ 112 __u8 sector_size[2]; /* bytes per logical sector */ 113 __u8 sec_per_clus; /* sectors/cluster */ 114 __le16 reserved; /* reserved sectors */ 115 __u8 fats; /* number of FATs */ 116 __u8 dir_entries[2]; /* root directory entries */ 117 __u8 sectors[2]; /* number of sectors */ 118 __u8 media; /* media code */ 119 __le16 fat_length; /* sectors/FAT */ 120 __le16 secs_track; /* sectors per track */ 121 __le16 heads; /* number of heads */ 122 __le32 hidden; /* hidden sectors (unused) */ 123 __le32 total_sect; /* number of sectors (if sectors == 0) */ 124 125 /* The following fields are only used by FAT32 */ 126 __le32 fat32_length; /* sectors/FAT */ 127 __le16 flags; /* bit 8: fat mirroring, low 4: active fat */ 128 __u8 version[2]; /* major, minor filesystem version */ 129 __le32 root_cluster; /* first cluster in root directory */ 130 __le16 info_sector; /* filesystem info sector */ 131 __le16 backup_boot; /* backup boot sector */ 132 __le16 reserved2[6]; /* Unused */ 133 }; 134 135 struct fat_boot_fsinfo { 136 __le32 signature1; /* 0x41615252L */ 137 __le32 reserved1[120]; /* Nothing as far as I can tell */ 138 __le32 signature2; /* 0x61417272L */ 139 __le32 free_clusters; /* Free cluster count. -1 if unknown */ 140 __le32 next_cluster; /* Most recently allocated cluster */ 141 __le32 reserved2[4]; 142 }; 143 144 struct msdos_dir_entry { 145 __u8 name[MSDOS_NAME];/* name and extension */ 146 __u8 attr; /* attribute bits */ 147 __u8 lcase; /* Case for base and extension */ 148 __u8 ctime_cs; /* Creation time, centiseconds (0-199) */ 149 __le16 ctime; /* Creation time */ 150 __le16 cdate; /* Creation date */ 151 __le16 adate; /* Last access date */ 152 __le16 starthi; /* High 16 bits of cluster in FAT32 */ 153 __le16 time,date,start;/* time, date and first cluster */ 154 __le32 size; /* file size (in bytes) */ 155 }; 156 157 /* Up to 13 characters of the name */ 158 struct msdos_dir_slot { 159 __u8 id; /* sequence number for slot */ 160 __u8 name0_4[10]; /* first 5 characters in name */ 161 __u8 attr; /* attribute byte */ 162 __u8 reserved; /* always 0 */ 163 __u8 alias_checksum; /* checksum for 8.3 alias */ 164 __u8 name5_10[12]; /* 6 more characters in name */ 165 __le16 start; /* starting cluster number, 0 in long slots */ 166 __u8 name11_12[4]; /* last 2 characters in name */ 167 }; 168 169 #ifdef __KERNEL__ 170 171 #include <linux/buffer_head.h> 172 #include <linux/string.h> 173 #include <linux/nls.h> 174 #include <linux/fs.h> 175 #include <linux/mutex.h> 176 177 /* 178 * vfat shortname flags 179 */ 180 #define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */ 181 #define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */ 182 #define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */ 183 #define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */ 184 #define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */ 185 186 struct fat_mount_options { 187 uid_t fs_uid; 188 gid_t fs_gid; 189 unsigned short fs_fmask; 190 unsigned short fs_dmask; 191 unsigned short codepage; /* Codepage for shortname conversions */ 192 char *iocharset; /* Charset used for filename input/display */ 193 unsigned short shortname; /* flags for shortname display/create rule */ 194 unsigned char name_check; /* r = relaxed, n = normal, s = strict */ 195 unsigned short allow_utime;/* permission for setting the [am]time */ 196 unsigned quiet:1, /* set = fake successful chmods and chowns */ 197 showexec:1, /* set = only set x bit for com/exe/bat */ 198 sys_immutable:1, /* set = system files are immutable */ 199 dotsOK:1, /* set = hidden and system files are named '.filename' */ 200 isvfat:1, /* 0=no vfat long filename support, 1=vfat support */ 201 utf8:1, /* Use of UTF-8 character set (Default) */ 202 unicode_xlate:1, /* create escape sequences for unhandled Unicode */ 203 numtail:1, /* Does first alias have a numeric '~1' type tail? */ 204 flush:1, /* write things quickly */ 205 nocase:1, /* Does this need case conversion? 0=need case conversion*/ 206 usefree:1, /* Use free_clusters for FAT32 */ 207 tz_utc:1; /* Filesystem timestamps are in UTC */ 208 }; 209 210 #define FAT_HASH_BITS 8 211 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) 212 #define FAT_HASH_MASK (FAT_HASH_SIZE-1) 213 214 /* 215 * MS-DOS file system in-core superblock data 216 */ 217 struct msdos_sb_info { 218 unsigned short sec_per_clus; /* sectors/cluster */ 219 unsigned short cluster_bits; /* log2(cluster_size) */ 220 unsigned int cluster_size; /* cluster size */ 221 unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ 222 unsigned short fat_start; 223 unsigned long fat_length; /* FAT start & length (sec.) */ 224 unsigned long dir_start; 225 unsigned short dir_entries; /* root dir start & entries */ 226 unsigned long data_start; /* first data sector */ 227 unsigned long max_cluster; /* maximum cluster number */ 228 unsigned long root_cluster; /* first cluster of the root directory */ 229 unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ 230 struct mutex fat_lock; 231 unsigned int prev_free; /* previously allocated cluster number */ 232 unsigned int free_clusters; /* -1 if undefined */ 233 unsigned int free_clus_valid; /* is free_clusters valid? */ 234 struct fat_mount_options options; 235 struct nls_table *nls_disk; /* Codepage used on disk */ 236 struct nls_table *nls_io; /* Charset used for input and display */ 237 const void *dir_ops; /* Opaque; default directory operations */ 238 int dir_per_block; /* dir entries per block */ 239 int dir_per_block_bits; /* log2(dir_per_block) */ 240 241 int fatent_shift; 242 struct fatent_operations *fatent_ops; 243 244 spinlock_t inode_hash_lock; 245 struct hlist_head inode_hashtable[FAT_HASH_SIZE]; 246 }; 247 248 #define FAT_CACHE_VALID 0 /* special case for valid cache */ 249 250 /* 251 * MS-DOS file system inode data in memory 252 */ 253 struct msdos_inode_info { 254 spinlock_t cache_lru_lock; 255 struct list_head cache_lru; 256 int nr_caches; 257 /* for avoiding the race between fat_free() and fat_get_cluster() */ 258 unsigned int cache_valid_id; 259 260 loff_t mmu_private; 261 int i_start; /* first cluster or 0 */ 262 int i_logstart; /* logical first cluster */ 263 int i_attrs; /* unused attribute bits */ 264 loff_t i_pos; /* on-disk position of directory entry or 0 */ 265 struct hlist_node i_fat_hash; /* hash by i_location */ 266 struct inode vfs_inode; 267 }; 268 269 struct fat_slot_info { 270 loff_t i_pos; /* on-disk position of directory entry */ 271 loff_t slot_off; /* offset for slot or de start */ 272 int nr_slots; /* number of slots + 1(de) in filename */ 273 struct msdos_dir_entry *de; 274 struct buffer_head *bh; 275 }; 276 277 static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) 278 { 279 return sb->s_fs_info; 280 } 281 282 static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) 283 { 284 return container_of(inode, struct msdos_inode_info, vfs_inode); 285 } 286 287 /* Return the FAT attribute byte for this inode */ 288 static inline u8 fat_attr(struct inode *inode) 289 { 290 return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) | 291 (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) | 292 MSDOS_I(inode)->i_attrs; 293 } 294 295 static inline unsigned char fat_checksum(const __u8 *name) 296 { 297 unsigned char s = name[0]; 298 s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2]; 299 s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4]; 300 s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6]; 301 s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8]; 302 s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10]; 303 return s; 304 } 305 306 static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) 307 { 308 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus 309 + sbi->data_start; 310 } 311 312 static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) 313 { 314 #ifdef __BIG_ENDIAN 315 while (len--) { 316 *dst++ = src[0] | (src[1] << 8); 317 src += 2; 318 } 319 #else 320 memcpy(dst, src, len * 2); 321 #endif 322 } 323 324 static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) 325 { 326 #ifdef __BIG_ENDIAN 327 while (len--) { 328 dst[0] = *src & 0x00FF; 329 dst[1] = (*src & 0xFF00) >> 8; 330 dst += 2; 331 src++; 332 } 333 #else 334 memcpy(dst, src, len * 2); 335 #endif 336 } 337 338 /* media of boot sector */ 339 static inline int fat_valid_media(u8 media) 340 { 341 return 0xf8 <= media || media == 0xf0; 342 } 343 344 /* fat/cache.c */ 345 extern void fat_cache_inval_inode(struct inode *inode); 346 extern int fat_get_cluster(struct inode *inode, int cluster, 347 int *fclus, int *dclus); 348 extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, 349 unsigned long *mapped_blocks); 350 351 /* fat/dir.c */ 352 extern const struct file_operations fat_dir_operations; 353 extern int fat_search_long(struct inode *inode, const unsigned char *name, 354 int name_len, struct fat_slot_info *sinfo); 355 extern int fat_dir_empty(struct inode *dir); 356 extern int fat_subdirs(struct inode *dir); 357 extern int fat_scan(struct inode *dir, const unsigned char *name, 358 struct fat_slot_info *sinfo); 359 extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 360 struct msdos_dir_entry **de, loff_t *i_pos); 361 extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); 362 extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 363 struct fat_slot_info *sinfo); 364 extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); 365 366 /* fat/fatent.c */ 367 struct fat_entry { 368 int entry; 369 union { 370 u8 *ent12_p[2]; 371 __le16 *ent16_p; 372 __le32 *ent32_p; 373 } u; 374 int nr_bhs; 375 struct buffer_head *bhs[2]; 376 }; 377 378 static inline void fatent_init(struct fat_entry *fatent) 379 { 380 fatent->nr_bhs = 0; 381 fatent->entry = 0; 382 fatent->u.ent32_p = NULL; 383 fatent->bhs[0] = fatent->bhs[1] = NULL; 384 } 385 386 static inline void fatent_set_entry(struct fat_entry *fatent, int entry) 387 { 388 fatent->entry = entry; 389 fatent->u.ent32_p = NULL; 390 } 391 392 static inline void fatent_brelse(struct fat_entry *fatent) 393 { 394 int i; 395 fatent->u.ent32_p = NULL; 396 for (i = 0; i < fatent->nr_bhs; i++) 397 brelse(fatent->bhs[i]); 398 fatent->nr_bhs = 0; 399 fatent->bhs[0] = fatent->bhs[1] = NULL; 400 } 401 402 extern void fat_ent_access_init(struct super_block *sb); 403 extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, 404 int entry); 405 extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, 406 int new, int wait); 407 extern int fat_alloc_clusters(struct inode *inode, int *cluster, 408 int nr_cluster); 409 extern int fat_free_clusters(struct inode *inode, int cluster); 410 extern int fat_count_free_clusters(struct super_block *sb); 411 412 /* fat/file.c */ 413 extern int fat_generic_ioctl(struct inode *inode, struct file *filp, 414 unsigned int cmd, unsigned long arg); 415 extern const struct file_operations fat_file_operations; 416 extern const struct inode_operations fat_file_inode_operations; 417 extern int fat_setattr(struct dentry * dentry, struct iattr * attr); 418 extern void fat_truncate(struct inode *inode); 419 extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, 420 struct kstat *stat); 421 422 /* fat/inode.c */ 423 extern void fat_attach(struct inode *inode, loff_t i_pos); 424 extern void fat_detach(struct inode *inode); 425 extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); 426 extern struct inode *fat_build_inode(struct super_block *sb, 427 struct msdos_dir_entry *de, loff_t i_pos); 428 extern int fat_sync_inode(struct inode *inode); 429 extern int fat_fill_super(struct super_block *sb, void *data, int silent, 430 const struct inode_operations *fs_dir_inode_ops, int isvfat); 431 432 extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, 433 struct inode *i2); 434 /* fat/misc.c */ 435 extern void fat_fs_panic(struct super_block *s, const char *fmt, ...); 436 extern void fat_clusters_flush(struct super_block *sb); 437 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); 438 extern int date_dos2unix(unsigned short time, unsigned short date, int tz_utc); 439 extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date, 440 int tz_utc); 441 extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); 442 443 int fat_cache_init(void); 444 void fat_cache_destroy(void); 445 446 #endif /* __KERNEL__ */ 447 448 #endif 449