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) 102 103/* 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 112struct 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 139struct 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 148struct 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 */ 162struct 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 173struct 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#include <linux/mutex.h> 188 189struct fat_mount_options { 190 uid_t fs_uid; 191 gid_t fs_gid; 192 unsigned short fs_fmask; 193 unsigned short fs_dmask; 194 unsigned short codepage; /* Codepage for shortname conversions */ 195 char *iocharset; /* Charset used for filename input/display */ 196 unsigned short shortname; /* flags for shortname display/create rule */ 197 unsigned char name_check; /* r = relaxed, n = normal, s = strict */ 198 unsigned quiet:1, /* set = fake successful chmods and chowns */ 199 showexec:1, /* set = only set x bit for com/exe/bat */ 200 sys_immutable:1, /* set = system files are immutable */ 201 dotsOK:1, /* set = hidden and system files are named '.filename' */ 202 isvfat:1, /* 0=no vfat long filename support, 1=vfat support */ 203 utf8:1, /* Use of UTF-8 character set (Default) */ 204 unicode_xlate:1, /* create escape sequences for unhandled Unicode */ 205 numtail:1, /* Does first alias have a numeric '~1' type tail? */ 206 atari:1, /* Use Atari GEMDOS variation of MS-DOS fs */ 207 flush:1, /* write things quickly */ 208 nocase:1, /* Does this need case conversion? 0=need case conversion*/ 209 usefree:1; /* Use free_clusters for FAT32 */ 210}; 211 212#define FAT_HASH_BITS 8 213#define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) 214#define FAT_HASH_MASK (FAT_HASH_SIZE-1) 215 216/* 217 * MS-DOS file system in-core superblock data 218 */ 219struct msdos_sb_info { 220 unsigned short sec_per_clus; /* sectors/cluster */ 221 unsigned short cluster_bits; /* log2(cluster_size) */ 222 unsigned int cluster_size; /* cluster size */ 223 unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ 224 unsigned short fat_start; 225 unsigned long fat_length; /* FAT start & length (sec.) */ 226 unsigned long dir_start; 227 unsigned short dir_entries; /* root dir start & entries */ 228 unsigned long data_start; /* first data sector */ 229 unsigned long max_cluster; /* maximum cluster number */ 230 unsigned long root_cluster; /* first cluster of the root directory */ 231 unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ 232 struct mutex fat_lock; 233 unsigned int prev_free; /* previously allocated cluster number */ 234 unsigned int free_clusters; /* -1 if undefined */ 235 struct fat_mount_options options; 236 struct nls_table *nls_disk; /* Codepage used on disk */ 237 struct nls_table *nls_io; /* Charset used for input and display */ 238 const void *dir_ops; /* Opaque; default directory operations */ 239 int dir_per_block; /* dir entries per block */ 240 int dir_per_block_bits; /* log2(dir_per_block) */ 241 242 int fatent_shift; 243 struct fatent_operations *fatent_ops; 244 245 spinlock_t inode_hash_lock; 246 struct hlist_head inode_hashtable[FAT_HASH_SIZE]; 247}; 248 249#define FAT_CACHE_VALID 0 /* special case for valid cache */ 250 251/* 252 * MS-DOS file system inode data in memory 253 */ 254struct msdos_inode_info { 255 spinlock_t cache_lru_lock; 256 struct list_head cache_lru; 257 int nr_caches; 258 /* for avoiding the race between fat_free() and fat_get_cluster() */ 259 unsigned int cache_valid_id; 260 261 loff_t mmu_private; 262 int i_start; /* first cluster or 0 */ 263 int i_logstart; /* logical first cluster */ 264 int i_attrs; /* unused attribute bits */ 265 loff_t i_pos; /* on-disk position of directory entry or 0 */ 266 struct hlist_node i_fat_hash; /* hash by i_location */ 267 struct inode vfs_inode; 268}; 269 270static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) 271{ 272 return sb->s_fs_info; 273} 274 275static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) 276{ 277 return container_of(inode, struct msdos_inode_info, vfs_inode); 278} 279 280/* Return the FAT attribute byte for this inode */ 281static inline u8 fat_attr(struct inode *inode) 282{ 283 return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) | 284 (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) | 285 MSDOS_I(inode)->i_attrs; 286} 287 288static inline unsigned char fat_checksum(const __u8 *name) 289{ 290 unsigned char s = name[0]; 291 s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2]; 292 s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4]; 293 s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6]; 294 s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8]; 295 s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10]; 296 return s; 297} 298 299static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) 300{ 301 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus 302 + sbi->data_start; 303} 304 305static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) 306{ 307#ifdef __BIG_ENDIAN 308 while (len--) { 309 *dst++ = src[0] | (src[1] << 8); 310 src += 2; 311 } 312#else 313 memcpy(dst, src, len * 2); 314#endif 315} 316 317static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) 318{ 319#ifdef __BIG_ENDIAN 320 while (len--) { 321 dst[0] = *src & 0x00FF; 322 dst[1] = (*src & 0xFF00) >> 8; 323 dst += 2; 324 src++; 325 } 326#else 327 memcpy(dst, src, len * 2); 328#endif 329} 330 331/* fat/cache.c */ 332extern void fat_cache_inval_inode(struct inode *inode); 333extern int fat_get_cluster(struct inode *inode, int cluster, 334 int *fclus, int *dclus); 335extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, 336 unsigned long *mapped_blocks); 337 338/* fat/dir.c */ 339extern const struct file_operations fat_dir_operations; 340extern int fat_search_long(struct inode *inode, const unsigned char *name, 341 int name_len, struct fat_slot_info *sinfo); 342extern int fat_dir_empty(struct inode *dir); 343extern int fat_subdirs(struct inode *dir); 344extern int fat_scan(struct inode *dir, const unsigned char *name, 345 struct fat_slot_info *sinfo); 346extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 347 struct msdos_dir_entry **de, loff_t *i_pos); 348extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); 349extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 350 struct fat_slot_info *sinfo); 351extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); 352 353/* fat/fatent.c */ 354struct fat_entry { 355 int entry; 356 union { 357 u8 *ent12_p[2]; 358 __le16 *ent16_p; 359 __le32 *ent32_p; 360 } u; 361 int nr_bhs; 362 struct buffer_head *bhs[2]; 363}; 364 365static inline void fatent_init(struct fat_entry *fatent) 366{ 367 fatent->nr_bhs = 0; 368 fatent->entry = 0; 369 fatent->u.ent32_p = NULL; 370 fatent->bhs[0] = fatent->bhs[1] = NULL; 371} 372 373static inline void fatent_set_entry(struct fat_entry *fatent, int entry) 374{ 375 fatent->entry = entry; 376 fatent->u.ent32_p = NULL; 377} 378 379static inline void fatent_brelse(struct fat_entry *fatent) 380{ 381 int i; 382 fatent->u.ent32_p = NULL; 383 for (i = 0; i < fatent->nr_bhs; i++) 384 brelse(fatent->bhs[i]); 385 fatent->nr_bhs = 0; 386 fatent->bhs[0] = fatent->bhs[1] = NULL; 387} 388 389extern void fat_ent_access_init(struct super_block *sb); 390extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, 391 int entry); 392extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, 393 int new, int wait); 394extern int fat_alloc_clusters(struct inode *inode, int *cluster, 395 int nr_cluster); 396extern int fat_free_clusters(struct inode *inode, int cluster); 397extern int fat_count_free_clusters(struct super_block *sb); 398 399/* fat/file.c */ 400extern int fat_generic_ioctl(struct inode *inode, struct file *filp, 401 unsigned int cmd, unsigned long arg); 402extern const struct file_operations fat_file_operations; 403extern const struct inode_operations fat_file_inode_operations; 404extern int fat_notify_change(struct dentry * dentry, struct iattr * attr); 405extern void fat_truncate(struct inode *inode); 406extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, 407 struct kstat *stat); 408 409/* fat/inode.c */ 410extern void fat_attach(struct inode *inode, loff_t i_pos); 411extern void fat_detach(struct inode *inode); 412extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); 413extern struct inode *fat_build_inode(struct super_block *sb, 414 struct msdos_dir_entry *de, loff_t i_pos); 415extern int fat_sync_inode(struct inode *inode); 416extern int fat_fill_super(struct super_block *sb, void *data, int silent, 417 const struct inode_operations *fs_dir_inode_ops, int isvfat); 418 419extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, 420 struct inode *i2); 421/* fat/misc.c */ 422extern void fat_fs_panic(struct super_block *s, const char *fmt, ...); 423extern void fat_clusters_flush(struct super_block *sb); 424extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); 425extern int date_dos2unix(unsigned short time, unsigned short date); 426extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date); 427extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); 428 429int fat_cache_init(void); 430void fat_cache_destroy(void); 431 432#endif /* __KERNEL__ */ 433 434#endif 435