1 #ifndef _LINUX_MSDOS_FS_H 2 #define _LINUX_MSDOS_FS_H 3 4 /* 5 * The MS-DOS filesystem constants/structures 6 */ 7 #include <asm/byteorder.h> 8 9 #define SECTOR_SIZE 512 /* sector size (bytes) */ 10 #define SECTOR_BITS 9 /* log2(SECTOR_SIZE) */ 11 #define MSDOS_DPB (MSDOS_DPS) /* dir entries per block */ 12 #define MSDOS_DPB_BITS 4 /* log2(MSDOS_DPB) */ 13 #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) 14 #define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */ 15 #define CF_LE_W(v) le16_to_cpu(v) 16 #define CF_LE_L(v) le32_to_cpu(v) 17 #define CT_LE_W(v) cpu_to_le16(v) 18 #define CT_LE_L(v) cpu_to_le32(v) 19 20 21 #define MSDOS_SUPER_MAGIC 0x4d44 /* MD */ 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 /* media of boot sector */ 61 #define FAT_VALID_MEDIA(x) ((0xF8 <= (x) && (x) <= 0xFF) || (x) == 0xF0) 62 #define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \ 63 MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x)) 64 65 /* start of data cluster's entry (number of reserved clusters) */ 66 #define FAT_START_ENT 2 67 68 /* maximum number of clusters */ 69 #define MAX_FAT12 0xFF4 70 #define MAX_FAT16 0xFFF4 71 #define MAX_FAT32 0x0FFFFFF6 72 #define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \ 73 MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12) 74 75 /* bad cluster mark */ 76 #define BAD_FAT12 0xFF7 77 #define BAD_FAT16 0xFFF7 78 #define BAD_FAT32 0x0FFFFFF7 79 80 /* standard EOF */ 81 #define EOF_FAT12 0xFFF 82 #define EOF_FAT16 0xFFFF 83 #define EOF_FAT32 0x0FFFFFFF 84 85 #define FAT_ENT_FREE (0) 86 #define FAT_ENT_BAD (BAD_FAT32) 87 #define FAT_ENT_EOF (EOF_FAT32) 88 89 #define FAT_FSINFO_SIG1 0x41615252 90 #define FAT_FSINFO_SIG2 0x61417272 91 #define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \ 92 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2) 93 94 /* 95 * ioctl commands 96 */ 97 #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct dirent [2]) 98 #define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct dirent [2]) 99 /* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */ 100 #define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32) 101 #define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32) 102 103 /* 104 * vfat shortname flags 105 */ 106 #define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */ 107 #define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */ 108 #define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */ 109 #define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */ 110 #define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */ 111 112 struct fat_boot_sector { 113 __u8 ignored[3]; /* Boot strap short or near jump */ 114 __u8 system_id[8]; /* Name - can be used to special case 115 partition manager volumes */ 116 __u8 sector_size[2]; /* bytes per logical sector */ 117 __u8 sec_per_clus; /* sectors/cluster */ 118 __le16 reserved; /* reserved sectors */ 119 __u8 fats; /* number of FATs */ 120 __u8 dir_entries[2]; /* root directory entries */ 121 __u8 sectors[2]; /* number of sectors */ 122 __u8 media; /* media code */ 123 __le16 fat_length; /* sectors/FAT */ 124 __le16 secs_track; /* sectors per track */ 125 __le16 heads; /* number of heads */ 126 __le32 hidden; /* hidden sectors (unused) */ 127 __le32 total_sect; /* number of sectors (if sectors == 0) */ 128 129 /* The following fields are only used by FAT32 */ 130 __le32 fat32_length; /* sectors/FAT */ 131 __le16 flags; /* bit 8: fat mirroring, low 4: active fat */ 132 __u8 version[2]; /* major, minor filesystem version */ 133 __le32 root_cluster; /* first cluster in root directory */ 134 __le16 info_sector; /* filesystem info sector */ 135 __le16 backup_boot; /* backup boot sector */ 136 __le16 reserved2[6]; /* Unused */ 137 }; 138 139 struct fat_boot_fsinfo { 140 __le32 signature1; /* 0x41615252L */ 141 __le32 reserved1[120]; /* Nothing as far as I can tell */ 142 __le32 signature2; /* 0x61417272L */ 143 __le32 free_clusters; /* Free cluster count. -1 if unknown */ 144 __le32 next_cluster; /* Most recently allocated cluster */ 145 __le32 reserved2[4]; 146 }; 147 148 struct msdos_dir_entry { 149 __u8 name[8],ext[3]; /* name and extension */ 150 __u8 attr; /* attribute bits */ 151 __u8 lcase; /* Case for base and extension */ 152 __u8 ctime_cs; /* Creation time, centiseconds (0-199) */ 153 __le16 ctime; /* Creation time */ 154 __le16 cdate; /* Creation date */ 155 __le16 adate; /* Last access date */ 156 __le16 starthi; /* High 16 bits of cluster in FAT32 */ 157 __le16 time,date,start;/* time, date and first cluster */ 158 __le32 size; /* file size (in bytes) */ 159 }; 160 161 /* Up to 13 characters of the name */ 162 struct msdos_dir_slot { 163 __u8 id; /* sequence number for slot */ 164 __u8 name0_4[10]; /* first 5 characters in name */ 165 __u8 attr; /* attribute byte */ 166 __u8 reserved; /* always 0 */ 167 __u8 alias_checksum; /* checksum for 8.3 alias */ 168 __u8 name5_10[12]; /* 6 more characters in name */ 169 __le16 start; /* starting cluster number, 0 in long slots */ 170 __u8 name11_12[4]; /* last 2 characters in name */ 171 }; 172 173 struct fat_slot_info { 174 loff_t i_pos; /* on-disk position of directory entry */ 175 loff_t slot_off; /* offset for slot or de start */ 176 int nr_slots; /* number of slots + 1(de) in filename */ 177 struct msdos_dir_entry *de; 178 struct buffer_head *bh; 179 }; 180 181 #ifdef __KERNEL__ 182 183 #include <linux/buffer_head.h> 184 #include <linux/string.h> 185 #include <linux/nls.h> 186 #include <linux/fs.h> 187 188 struct fat_mount_options { 189 uid_t fs_uid; 190 gid_t fs_gid; 191 unsigned short fs_fmask; 192 unsigned short fs_dmask; 193 unsigned short codepage; /* Codepage for shortname conversions */ 194 char *iocharset; /* Charset used for filename input/display */ 195 unsigned short shortname; /* flags for shortname display/create rule */ 196 unsigned char name_check; /* r = relaxed, n = normal, s = strict */ 197 unsigned quiet:1, /* set = fake successful chmods and chowns */ 198 showexec:1, /* set = only set x bit for com/exe/bat */ 199 sys_immutable:1, /* set = system files are immutable */ 200 dotsOK:1, /* set = hidden and system files are named '.filename' */ 201 isvfat:1, /* 0=no vfat long filename support, 1=vfat support */ 202 utf8:1, /* Use of UTF8 character set (Default) */ 203 unicode_xlate:1, /* create escape sequences for unhandled Unicode */ 204 numtail:1, /* Does first alias have a numeric '~1' type tail? */ 205 atari:1, /* Use Atari GEMDOS variation of MS-DOS fs */ 206 nocase:1; /* Does this need case conversion? 0=need case conversion*/ 207 }; 208 209 #define FAT_HASH_BITS 8 210 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) 211 #define FAT_HASH_MASK (FAT_HASH_SIZE-1) 212 213 /* 214 * MS-DOS file system in-core superblock data 215 */ 216 struct msdos_sb_info { 217 unsigned short sec_per_clus; /* sectors/cluster */ 218 unsigned short cluster_bits; /* log2(cluster_size) */ 219 unsigned int cluster_size; /* cluster size */ 220 unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ 221 unsigned short fat_start; 222 unsigned long fat_length; /* FAT start & length (sec.) */ 223 unsigned long dir_start; 224 unsigned short dir_entries; /* root dir start & entries */ 225 unsigned long data_start; /* first data sector */ 226 unsigned long max_cluster; /* maximum cluster number */ 227 unsigned long root_cluster; /* first cluster of the root directory */ 228 unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ 229 struct semaphore fat_lock; 230 unsigned int prev_free; /* previously allocated cluster number */ 231 unsigned int free_clusters; /* -1 if undefined */ 232 struct fat_mount_options options; 233 struct nls_table *nls_disk; /* Codepage used on disk */ 234 struct nls_table *nls_io; /* Charset used for input and display */ 235 void *dir_ops; /* Opaque; default directory operations */ 236 int dir_per_block; /* dir entries per block */ 237 int dir_per_block_bits; /* log2(dir_per_block) */ 238 239 int fatent_shift; 240 struct fatent_operations *fatent_ops; 241 242 spinlock_t inode_hash_lock; 243 struct hlist_head inode_hashtable[FAT_HASH_SIZE]; 244 }; 245 246 #define FAT_CACHE_VALID 0 /* special case for valid cache */ 247 248 /* 249 * MS-DOS file system inode data in memory 250 */ 251 struct msdos_inode_info { 252 spinlock_t cache_lru_lock; 253 struct list_head cache_lru; 254 int nr_caches; 255 /* for avoiding the race between fat_free() and fat_get_cluster() */ 256 unsigned int cache_valid_id; 257 258 loff_t mmu_private; 259 int i_start; /* first cluster or 0 */ 260 int i_logstart; /* logical first cluster */ 261 int i_attrs; /* unused attribute bits */ 262 loff_t i_pos; /* on-disk position of directory entry or 0 */ 263 struct hlist_node i_fat_hash; /* hash by i_location */ 264 struct inode vfs_inode; 265 }; 266 267 static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) 268 { 269 return sb->s_fs_info; 270 } 271 272 static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) 273 { 274 return container_of(inode, struct msdos_inode_info, vfs_inode); 275 } 276 277 /* Return the FAT attribute byte for this inode */ 278 static inline u8 fat_attr(struct inode *inode) 279 { 280 return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) | 281 (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) | 282 MSDOS_I(inode)->i_attrs; 283 } 284 285 static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) 286 { 287 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus 288 + sbi->data_start; 289 } 290 291 static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) 292 { 293 #ifdef __BIG_ENDIAN 294 while (len--) { 295 *dst++ = src[0] | (src[1] << 8); 296 src += 2; 297 } 298 #else 299 memcpy(dst, src, len * 2); 300 #endif 301 } 302 303 static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) 304 { 305 #ifdef __BIG_ENDIAN 306 while (len--) { 307 dst[0] = *src & 0x00FF; 308 dst[1] = (*src & 0xFF00) >> 8; 309 dst += 2; 310 src++; 311 } 312 #else 313 memcpy(dst, src, len * 2); 314 #endif 315 } 316 317 /* fat/cache.c */ 318 extern void fat_cache_inval_inode(struct inode *inode); 319 extern int fat_get_cluster(struct inode *inode, int cluster, 320 int *fclus, int *dclus); 321 extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys); 322 323 /* fat/dir.c */ 324 extern struct file_operations fat_dir_operations; 325 extern int fat_search_long(struct inode *inode, const unsigned char *name, 326 int name_len, struct fat_slot_info *sinfo); 327 extern int fat_dir_empty(struct inode *dir); 328 extern int fat_subdirs(struct inode *dir); 329 extern int fat_scan(struct inode *dir, const unsigned char *name, 330 struct fat_slot_info *sinfo); 331 extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 332 struct msdos_dir_entry **de, loff_t *i_pos); 333 extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); 334 extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 335 struct fat_slot_info *sinfo); 336 extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); 337 338 /* fat/fatent.c */ 339 struct fat_entry { 340 int entry; 341 union { 342 u8 *ent12_p[2]; 343 __le16 *ent16_p; 344 __le32 *ent32_p; 345 } u; 346 int nr_bhs; 347 struct buffer_head *bhs[2]; 348 }; 349 350 static inline void fatent_init(struct fat_entry *fatent) 351 { 352 fatent->nr_bhs = 0; 353 fatent->entry = 0; 354 fatent->u.ent32_p = NULL; 355 fatent->bhs[0] = fatent->bhs[1] = NULL; 356 } 357 358 static inline void fatent_set_entry(struct fat_entry *fatent, int entry) 359 { 360 fatent->entry = entry; 361 fatent->u.ent32_p = NULL; 362 } 363 364 static inline void fatent_brelse(struct fat_entry *fatent) 365 { 366 int i; 367 fatent->u.ent32_p = NULL; 368 for (i = 0; i < fatent->nr_bhs; i++) 369 brelse(fatent->bhs[i]); 370 fatent->nr_bhs = 0; 371 fatent->bhs[0] = fatent->bhs[1] = NULL; 372 } 373 374 extern void fat_ent_access_init(struct super_block *sb); 375 extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, 376 int entry); 377 extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, 378 int new, int wait); 379 extern int fat_alloc_clusters(struct inode *inode, int *cluster, 380 int nr_cluster); 381 extern int fat_free_clusters(struct inode *inode, int cluster); 382 extern int fat_count_free_clusters(struct super_block *sb); 383 384 /* fat/file.c */ 385 extern int fat_generic_ioctl(struct inode *inode, struct file *filp, 386 unsigned int cmd, unsigned long arg); 387 extern struct file_operations fat_file_operations; 388 extern struct inode_operations fat_file_inode_operations; 389 extern int fat_notify_change(struct dentry * dentry, struct iattr * attr); 390 extern void fat_truncate(struct inode *inode); 391 392 /* fat/inode.c */ 393 extern void fat_attach(struct inode *inode, loff_t i_pos); 394 extern void fat_detach(struct inode *inode); 395 extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); 396 extern struct inode *fat_build_inode(struct super_block *sb, 397 struct msdos_dir_entry *de, loff_t i_pos); 398 extern int fat_sync_inode(struct inode *inode); 399 extern int fat_fill_super(struct super_block *sb, void *data, int silent, 400 struct inode_operations *fs_dir_inode_ops, int isvfat); 401 402 /* fat/misc.c */ 403 extern void fat_fs_panic(struct super_block *s, const char *fmt, ...); 404 extern void fat_clusters_flush(struct super_block *sb); 405 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); 406 extern int date_dos2unix(unsigned short time, unsigned short date); 407 extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date); 408 extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); 409 410 #endif /* __KERNEL__ */ 411 412 #endif 413