1#ifndef _LINUX_MSDOS_FS_H 2#define _LINUX_MSDOS_FS_H 3 4#include <linux/magic.h> 5 6/* 7 * The MS-DOS filesystem constants/structures 8 */ 9#include <asm/byteorder.h> 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/* 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#define VFAT_IOCTL_GET_VOLUME_ID _IOR('r', 0x12, __u32) 103 104/* 105 * vfat shortname flags 106 */ 107#define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */ 108#define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */ 109#define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */ 110#define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */ 111#define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */ 112 113struct fat_boot_sector { 114 __u8 ignored[3]; /* Boot strap short or near jump */ 115 __u8 system_id[8]; /* Name - can be used to special case 116 partition manager volumes */ 117 __u8 sector_size[2]; /* bytes per logical sector */ 118 __u8 sec_per_clus; /* sectors/cluster */ 119 __le16 reserved; /* reserved sectors */ 120 __u8 fats; /* number of FATs */ 121 __u8 dir_entries[2]; /* root directory entries */ 122 __u8 sectors[2]; /* number of sectors */ 123 __u8 media; /* media code */ 124 __le16 fat_length; /* sectors/FAT */ 125 __le16 secs_track; /* sectors per track */ 126 __le16 heads; /* number of heads */ 127 __le32 hidden; /* hidden sectors (unused) */ 128 __le32 total_sect; /* number of sectors (if sectors == 0) */ 129 130 /* The following fields are only used by FAT32 */ 131 __le32 fat32_length; /* sectors/FAT */ 132 __le16 flags; /* bit 8: fat mirroring, low 4: active fat */ 133 __u8 version[2]; /* major, minor filesystem version */ 134 __le32 root_cluster; /* first cluster in root directory */ 135 __le16 info_sector; /* filesystem info sector */ 136 __le16 backup_boot; /* backup boot sector */ 137 __le16 reserved2[6]; /* Unused */ 138}; 139 140struct fat_boot_fsinfo { 141 __le32 signature1; /* 0x41615252L */ 142 __le32 reserved1[120]; /* Nothing as far as I can tell */ 143 __le32 signature2; /* 0x61417272L */ 144 __le32 free_clusters; /* Free cluster count. -1 if unknown */ 145 __le32 next_cluster; /* Most recently allocated cluster */ 146 __le32 reserved2[4]; 147}; 148 149struct fat_boot_bsx { 150 __u8 drive; /* drive number */ 151 __u8 reserved1; 152 __u8 signature; /* extended boot signature */ 153 __u8 vol_id[4]; /* volume ID */ 154 __u8 vol_label[11]; /* volume label */ 155 __u8 type[8]; /* file system type */ 156}; 157#define FAT16_BSX_OFFSET 36 /* offset of fat_boot_bsx in FAT12 and FAT16 */ 158#define FAT32_BSX_OFFSET 64 /* offset of fat_boot_bsx in FAT32 */ 159 160struct msdos_dir_entry { 161 __u8 name[MSDOS_NAME];/* name and extension */ 162 __u8 attr; /* attribute bits */ 163 __u8 lcase; /* Case for base and extension */ 164 __u8 ctime_cs; /* Creation time, centiseconds (0-199) */ 165 __le16 ctime; /* Creation time */ 166 __le16 cdate; /* Creation date */ 167 __le16 adate; /* Last access date */ 168 __le16 starthi; /* High 16 bits of cluster in FAT32 */ 169 __le16 time,date,start;/* time, date and first cluster */ 170 __le32 size; /* file size (in bytes) */ 171}; 172 173/* Up to 13 characters of the name */ 174struct msdos_dir_slot { 175 __u8 id; /* sequence number for slot */ 176 __u8 name0_4[10]; /* first 5 characters in name */ 177 __u8 attr; /* attribute byte */ 178 __u8 reserved; /* always 0 */ 179 __u8 alias_checksum; /* checksum for 8.3 alias */ 180 __u8 name5_10[12]; /* 6 more characters in name */ 181 __le16 start; /* starting cluster number, 0 in long slots */ 182 __u8 name11_12[4]; /* last 2 characters in name */ 183}; 184 185struct fat_slot_info { 186 loff_t i_pos; /* on-disk position of directory entry */ 187 loff_t slot_off; /* offset for slot or de start */ 188 int nr_slots; /* number of slots + 1(de) in filename */ 189 struct msdos_dir_entry *de; 190 struct buffer_head *bh; 191}; 192 193#ifdef __KERNEL__ 194 195#include <linux/buffer_head.h> 196#include <linux/string.h> 197#include <linux/nls.h> 198#include <linux/fs.h> 199#include <linux/mutex.h> 200 201struct fat_mount_options { 202 uid_t fs_uid; 203 gid_t fs_gid; 204 unsigned short fs_fmask; 205 unsigned short fs_dmask; 206 unsigned short codepage; /* Codepage for shortname conversions */ 207 char *iocharset; /* Charset used for filename input/display */ 208 unsigned short shortname; /* flags for shortname display/create rule */ 209 unsigned char name_check; /* r = relaxed, n = normal, s = strict */ 210 unsigned quiet:1, /* set = fake successful chmods and chowns */ 211 showexec:1, /* set = only set x bit for com/exe/bat */ 212 sys_immutable:1, /* set = system files are immutable */ 213 dotsOK:1, /* set = hidden and system files are named '.filename' */ 214 isvfat:1, /* 0=no vfat long filename support, 1=vfat support */ 215 utf8:1, /* Use of UTF-8 character set (Default) */ 216 unicode_xlate:1, /* create escape sequences for unhandled Unicode */ 217 numtail:1, /* Does first alias have a numeric '~1' type tail? */ 218 atari:1, /* Use Atari GEMDOS variation of MS-DOS fs */ 219 flush:1, /* write things quickly */ 220 nocase:1, /* Does this need case conversion? 0=need case conversion*/ 221 usefree:1; /* Use free_clusters for FAT32 */ 222}; 223 224#define FAT_HASH_BITS 8 225#define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) 226#define FAT_HASH_MASK (FAT_HASH_SIZE-1) 227 228/* 229 * MS-DOS file system in-core superblock data 230 */ 231struct msdos_sb_info { 232 unsigned short sec_per_clus; /* sectors/cluster */ 233 unsigned short cluster_bits; /* log2(cluster_size) */ 234 unsigned int cluster_size; /* cluster size */ 235 unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ 236 unsigned short fat_start; 237 unsigned long fat_length; /* FAT start & length (sec.) */ 238 unsigned long dir_start; 239 unsigned short dir_entries; /* root dir start & entries */ 240 unsigned long data_start; /* first data sector */ 241 unsigned long max_cluster; /* maximum cluster number */ 242 unsigned long root_cluster; /* first cluster of the root directory */ 243 unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ 244 struct mutex fat_lock; 245 unsigned int prev_free; /* previously allocated cluster number */ 246 unsigned int free_clusters; /* -1 if undefined */ 247 struct fat_mount_options options; 248 struct nls_table *nls_disk; /* Codepage used on disk */ 249 struct nls_table *nls_io; /* Charset used for input and display */ 250 const void *dir_ops; /* Opaque; default directory operations */ 251 int dir_per_block; /* dir entries per block */ 252 int dir_per_block_bits; /* log2(dir_per_block) */ 253 unsigned long vol_id; /* volume ID */ 254 255 int fatent_shift; 256 struct fatent_operations *fatent_ops; 257 258 spinlock_t inode_hash_lock; 259 struct hlist_head inode_hashtable[FAT_HASH_SIZE]; 260}; 261 262#define FAT_CACHE_VALID 0 /* special case for valid cache */ 263 264/* 265 * MS-DOS file system inode data in memory 266 */ 267struct msdos_inode_info { 268 spinlock_t cache_lru_lock; 269 struct list_head cache_lru; 270 int nr_caches; 271 /* for avoiding the race between fat_free() and fat_get_cluster() */ 272 unsigned int cache_valid_id; 273 274 loff_t mmu_private; 275 int i_start; /* first cluster or 0 */ 276 int i_logstart; /* logical first cluster */ 277 int i_attrs; /* unused attribute bits */ 278 loff_t i_pos; /* on-disk position of directory entry or 0 */ 279 struct hlist_node i_fat_hash; /* hash by i_location */ 280 struct inode vfs_inode; 281}; 282 283static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) 284{ 285 return sb->s_fs_info; 286} 287 288static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) 289{ 290 return container_of(inode, struct msdos_inode_info, vfs_inode); 291} 292 293/* Return the FAT attribute byte for this inode */ 294static inline u8 fat_attr(struct inode *inode) 295{ 296 return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) | 297 (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) | 298 MSDOS_I(inode)->i_attrs; 299} 300 301static inline unsigned char fat_checksum(const __u8 *name) 302{ 303 unsigned char s = name[0]; 304 s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2]; 305 s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4]; 306 s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6]; 307 s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8]; 308 s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10]; 309 return s; 310} 311 312static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) 313{ 314 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus 315 + sbi->data_start; 316} 317 318static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) 319{ 320#ifdef __BIG_ENDIAN 321 while (len--) { 322 *dst++ = src[0] | (src[1] << 8); 323 src += 2; 324 } 325#else 326 memcpy(dst, src, len * 2); 327#endif 328} 329 330static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) 331{ 332#ifdef __BIG_ENDIAN 333 while (len--) { 334 dst[0] = *src & 0x00FF; 335 dst[1] = (*src & 0xFF00) >> 8; 336 dst += 2; 337 src++; 338 } 339#else 340 memcpy(dst, src, len * 2); 341#endif 342} 343 344/* fat/cache.c */ 345extern void fat_cache_inval_inode(struct inode *inode); 346extern int fat_get_cluster(struct inode *inode, int cluster, 347 int *fclus, int *dclus); 348extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, 349 unsigned long *mapped_blocks); 350 351/* fat/dir.c */ 352extern const struct file_operations fat_dir_operations; 353extern int fat_search_long(struct inode *inode, const unsigned char *name, 354 int name_len, struct fat_slot_info *sinfo); 355extern int fat_dir_empty(struct inode *dir); 356extern int fat_subdirs(struct inode *dir); 357extern int fat_scan(struct inode *dir, const unsigned char *name, 358 struct fat_slot_info *sinfo); 359extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 360 struct msdos_dir_entry **de, loff_t *i_pos); 361extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); 362extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 363 struct fat_slot_info *sinfo); 364extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); 365 366/* fat/fatent.c */ 367struct 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 378static 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 386static inline void fatent_set_entry(struct fat_entry *fatent, int entry) 387{ 388 fatent->entry = entry; 389 fatent->u.ent32_p = NULL; 390} 391 392static 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 402extern void fat_ent_access_init(struct super_block *sb); 403extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, 404 int entry); 405extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, 406 int new, int wait); 407extern int fat_alloc_clusters(struct inode *inode, int *cluster, 408 int nr_cluster); 409extern int fat_free_clusters(struct inode *inode, int cluster); 410extern int fat_count_free_clusters(struct super_block *sb); 411 412/* fat/file.c */ 413extern int fat_generic_ioctl(struct inode *inode, struct file *filp, 414 unsigned int cmd, unsigned long arg); 415extern const struct file_operations fat_file_operations; 416extern const struct inode_operations fat_file_inode_operations; 417extern int fat_notify_change(struct dentry * dentry, struct iattr * attr); 418extern void fat_truncate(struct inode *inode); 419extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, 420 struct kstat *stat); 421 422/* fat/inode.c */ 423extern void fat_attach(struct inode *inode, loff_t i_pos); 424extern void fat_detach(struct inode *inode); 425extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); 426extern struct inode *fat_build_inode(struct super_block *sb, 427 struct msdos_dir_entry *de, loff_t i_pos); 428extern int fat_sync_inode(struct inode *inode); 429extern int fat_fill_super(struct super_block *sb, void *data, int silent, 430 const struct inode_operations *fs_dir_inode_ops, int isvfat); 431 432extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, 433 struct inode *i2); 434/* fat/misc.c */ 435extern void fat_fs_panic(struct super_block *s, const char *fmt, ...); 436extern void fat_clusters_flush(struct super_block *sb); 437extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); 438extern int date_dos2unix(unsigned short time, unsigned short date); 439extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date); 440extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); 441 442int fat_cache_init(void); 443void fat_cache_destroy(void); 444 445#endif /* __KERNEL__ */ 446 447#endif 448