1 #ifndef _LINUX_MSDOS_FS_H
2 #define _LINUX_MSDOS_FS_H
5 * The MS-DOS filesystem constants/structures
7 #include <asm/byteorder.h>
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)
21 #define MSDOS_SUPER_MAGIC 0x4d44 /* MD */
23 #define MSDOS_ROOT_INO 1 /* == MINIX_ROOT_INO */
24 #define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */
27 #define FAT_MAX_DIR_ENTRIES (65536)
28 #define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS)
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 */
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)
43 #define CASE_LOWER_BASE 8 /* base is lower case */
44 #define CASE_LOWER_EXT 16 /* extension is lower case */
46 #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */
47 #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG)
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 /* Convert the UNIX mode to MS-DOS attribute bits. */
54 #define MSDOS_MKATTR(m) ((m & S_IWUGO) ? ATTR_NONE : ATTR_RO)
56 #define MSDOS_NAME 11 /* maximum name length */
57 #define MSDOS_LONGNAME 256 /* maximum name length */
58 #define MSDOS_SLOTS 21 /* max # of slots for short and long names */
59 #define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */
60 #define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */
62 /* media of boot sector */
63 #define FAT_VALID_MEDIA(x) ((0xF8 <= (x) && (x) <= 0xFF) || (x) == 0xF0)
64 #define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \
65 MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x))
67 /* start of data cluster's entry (number of reserved clusters) */
68 #define FAT_START_ENT 2
70 /* maximum number of clusters */
71 #define MAX_FAT12 0xFF4
72 #define MAX_FAT16 0xFFF4
73 #define MAX_FAT32 0x0FFFFFF6
74 #define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \
75 MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12)
77 /* bad cluster mark */
78 #define BAD_FAT12 0xFF7
79 #define BAD_FAT16 0xFFF7
80 #define BAD_FAT32 0x0FFFFFF7
81 #define BAD_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? BAD_FAT32 : \
82 MSDOS_SB(s)->fat_bits == 16 ? BAD_FAT16 : BAD_FAT12)
85 #define EOF_FAT12 0xFFF
86 #define EOF_FAT16 0xFFFF
87 #define EOF_FAT32 0x0FFFFFFF
88 #define EOF_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? EOF_FAT32 : \
89 MSDOS_SB(s)->fat_bits == 16 ? EOF_FAT16 : EOF_FAT12)
91 #define FAT_ENT_FREE (0)
92 #define FAT_ENT_BAD (BAD_FAT32)
93 #define FAT_ENT_EOF (EOF_FAT32)
95 #define FAT_FSINFO_SIG1 0x41615252
96 #define FAT_FSINFO_SIG2 0x61417272
97 #define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \
98 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2)
103 #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct dirent [2])
104 #define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct dirent [2])
107 * vfat shortname flags
109 #define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */
110 #define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */
111 #define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */
112 #define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */
113 #define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */
115 struct fat_boot_sector {
116 __u8 ignored[3]; /* Boot strap short or near jump */
117 __u8 system_id[8]; /* Name - can be used to special case
118 partition manager volumes */
119 __u8 sector_size[2]; /* bytes per logical sector */
120 __u8 sec_per_clus; /* sectors/cluster */
121 __le16 reserved; /* reserved sectors */
122 __u8 fats; /* number of FATs */
123 __u8 dir_entries[2]; /* root directory entries */
124 __u8 sectors[2]; /* number of sectors */
125 __u8 media; /* media code */
126 __le16 fat_length; /* sectors/FAT */
127 __le16 secs_track; /* sectors per track */
128 __le16 heads; /* number of heads */
129 __le32 hidden; /* hidden sectors (unused) */
130 __le32 total_sect; /* number of sectors (if sectors == 0) */
132 /* The following fields are only used by FAT32 */
133 __le32 fat32_length; /* sectors/FAT */
134 __le16 flags; /* bit 8: fat mirroring, low 4: active fat */
135 __u8 version[2]; /* major, minor filesystem version */
136 __le32 root_cluster; /* first cluster in root directory */
137 __le16 info_sector; /* filesystem info sector */
138 __le16 backup_boot; /* backup boot sector */
139 __le16 reserved2[6]; /* Unused */
142 struct fat_boot_fsinfo {
143 __le32 signature1; /* 0x41615252L */
144 __le32 reserved1[120]; /* Nothing as far as I can tell */
145 __le32 signature2; /* 0x61417272L */
146 __le32 free_clusters; /* Free cluster count. -1 if unknown */
147 __le32 next_cluster; /* Most recently allocated cluster */
151 struct msdos_dir_entry {
152 __u8 name[8],ext[3]; /* name and extension */
153 __u8 attr; /* attribute bits */
154 __u8 lcase; /* Case for base and extension */
155 __u8 ctime_ms; /* Creation time, milliseconds */
156 __le16 ctime; /* Creation time */
157 __le16 cdate; /* Creation date */
158 __le16 adate; /* Last access date */
159 __le16 starthi; /* High 16 bits of cluster in FAT32 */
160 __le16 time,date,start;/* time, date and first cluster */
161 __le32 size; /* file size (in bytes) */
164 /* Up to 13 characters of the name */
165 struct msdos_dir_slot {
166 __u8 id; /* sequence number for slot */
167 __u8 name0_4[10]; /* first 5 characters in name */
168 __u8 attr; /* attribute byte */
169 __u8 reserved; /* always 0 */
170 __u8 alias_checksum; /* checksum for 8.3 alias */
171 __u8 name5_10[12]; /* 6 more characters in name */
172 __le16 start; /* starting cluster number, 0 in long slots */
173 __u8 name11_12[4]; /* last 2 characters in name */
176 struct vfat_slot_info {
177 int long_slots; /* number of long slots in filename */
178 loff_t longname_offset; /* dir offset for longname start */
179 loff_t i_pos; /* on-disk position of directory entry */
184 #include <linux/buffer_head.h>
185 #include <linux/string.h>
186 #include <linux/nls.h>
187 #include <linux/fs.h>
189 struct fat_mount_options {
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 UTF8 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 nocase:1; /* Does this need case conversion? 0=need case conversion*/
210 #define FAT_HASH_BITS 8
211 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS)
212 #define FAT_HASH_MASK (FAT_HASH_SIZE-1)
215 * MS-DOS file system in-core superblock data
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 semaphore fat_lock;
231 int prev_free; /* previously allocated cluster number */
232 int free_clusters; /* -1 if undefined */
233 struct fat_mount_options options;
234 struct nls_table *nls_disk; /* Codepage used on disk */
235 struct nls_table *nls_io; /* Charset used for input and display */
236 void *dir_ops; /* Opaque; default directory operations */
237 int dir_per_block; /* dir entries per block */
238 int dir_per_block_bits; /* log2(dir_per_block) */
240 spinlock_t inode_hash_lock;
241 struct hlist_head inode_hashtable[FAT_HASH_SIZE];
244 #define FAT_CACHE_VALID 0 /* special case for valid cache */
247 * MS-DOS file system inode data in memory
249 struct msdos_inode_info {
250 spinlock_t cache_lru_lock;
251 struct list_head cache_lru;
253 /* for avoiding the race between fat_free() and fat_get_cluster() */
254 unsigned int cache_valid_id;
257 int i_start; /* first cluster or 0 */
258 int i_logstart; /* logical first cluster */
259 int i_attrs; /* unused attribute bits */
260 int i_ctime_ms; /* unused change time in milliseconds */
261 loff_t i_pos; /* on-disk position of directory entry or 0 */
262 struct hlist_node i_fat_hash; /* hash by i_location */
263 struct inode vfs_inode;
266 static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb)
268 return sb->s_fs_info;
271 static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
273 return container_of(inode, struct msdos_inode_info, vfs_inode);
276 static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus)
278 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus
282 static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len)
286 *dst++ = src[0] | (src[1] << 8);
290 memcpy(dst, src, len * 2);
294 static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len)
298 dst[0] = *src & 0x00FF;
299 dst[1] = (*src & 0xFF00) >> 8;
304 memcpy(dst, src, len * 2);
309 extern void fat_cache_inval_inode(struct inode *inode);
310 extern int fat_access(struct super_block *sb, int nr, int new_value);
311 extern int fat_get_cluster(struct inode *inode, int cluster,
312 int *fclus, int *dclus);
313 extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys);
316 extern struct file_operations fat_dir_operations;
317 extern int fat_search_long(struct inode *inode, const unsigned char *name,
318 int name_len, int anycase,
319 loff_t *spos, loff_t *lpos);
320 extern int fat_add_entries(struct inode *dir, int slots,
321 struct buffer_head **bh,
322 struct msdos_dir_entry **de, loff_t *i_pos);
323 extern int fat_new_dir(struct inode *dir, struct inode *parent, int is_vfat);
324 extern int fat_dir_empty(struct inode *dir);
325 extern int fat_subdirs(struct inode *dir);
326 extern int fat_scan(struct inode *dir, const unsigned char *name,
327 struct buffer_head **res_bh,
328 struct msdos_dir_entry **res_de, loff_t *i_pos);
331 extern struct file_operations fat_file_operations;
332 extern struct inode_operations fat_file_inode_operations;
333 extern int fat_notify_change(struct dentry * dentry, struct iattr * attr);
334 extern void fat_truncate(struct inode *inode);
337 extern void fat_attach(struct inode *inode, loff_t i_pos);
338 extern void fat_detach(struct inode *inode);
339 extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos);
340 extern struct inode *fat_build_inode(struct super_block *sb,
341 struct msdos_dir_entry *de, loff_t i_pos, int *res);
342 int fat_fill_super(struct super_block *sb, void *data, int silent,
343 struct inode_operations *fs_dir_inode_ops, int isvfat);
346 extern void fat_fs_panic(struct super_block *s, const char *fmt, ...);
347 extern void lock_fat(struct super_block *sb);
348 extern void unlock_fat(struct super_block *sb);
349 extern void fat_clusters_flush(struct super_block *sb);
350 extern int fat_add_cluster(struct inode *inode);
351 extern int date_dos2unix(unsigned short time, unsigned short date);
352 extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date);
353 extern int fat__get_entry(struct inode *dir, loff_t *pos,
354 struct buffer_head **bh,
355 struct msdos_dir_entry **de, loff_t *i_pos);
356 static __inline__ int fat_get_entry(struct inode *dir, loff_t *pos,
357 struct buffer_head **bh,
358 struct msdos_dir_entry **de, loff_t *i_pos)
360 /* Fast stuff first */
362 (*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
363 *pos += sizeof(struct msdos_dir_entry);
368 return fat__get_entry(dir, pos, bh, de, i_pos);
371 #endif /* __KERNEL__ */