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#ifndef _LINUX_MSDOS_FS_H
#define _LINUX_MSDOS_FS_H
/*
* The MS-DOS filesystem constants/structures
*/
#include <asm/byteorder.h>
#define SECTOR_SIZE 512 /* sector size (bytes) */
#define SECTOR_BITS 9 /* log2(SECTOR_SIZE) */
#define MSDOS_DPB (MSDOS_DPS) /* dir entries per block */
#define MSDOS_DPB_BITS 4 /* log2(MSDOS_DPB) */
#define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry))
#define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */
#define MSDOS_SUPER_MAGIC 0x4d44 /* MD */
#define MSDOS_ROOT_INO 1 /* == MINIX_ROOT_INO */
#define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */
/* directory limit */
#define FAT_MAX_DIR_ENTRIES (65536)
#define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS)
#define ATTR_NONE 0 /* no attribute bits */
#define ATTR_RO 1 /* read-only */
#define ATTR_HIDDEN 2 /* hidden */
#define ATTR_SYS 4 /* system */
#define ATTR_VOLUME 8 /* volume label */
#define ATTR_DIR 16 /* directory */
#define ATTR_ARCH 32 /* archived */
/* attribute bits that are copied "as is" */
#define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN)
/* bits that are used by the Windows 95/Windows NT extended FAT */
#define ATTR_EXT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME)
#define CASE_LOWER_BASE 8 /* base is lower case */
#define CASE_LOWER_EXT 16 /* extension is lower case */
#define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */
#define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG)
/* valid file mode bits */
#define MSDOS_VALID_MODE (S_IFREG | S_IFDIR | S_IRWXU | S_IRWXG | S_IRWXO)
/* Convert attribute bits and a mask to the UNIX mode. */
#define MSDOS_MKMODE(a, m) (m & (a & ATTR_RO ? S_IRUGO|S_IXUGO : S_IRWXUGO))
/* Convert the UNIX mode to MS-DOS attribute bits. */
#define MSDOS_MKATTR(m) ((m & S_IWUGO) ? ATTR_NONE : ATTR_RO)
#define MSDOS_NAME 11 /* maximum name length */
#define MSDOS_LONGNAME 256 /* maximum name length */
#define MSDOS_SLOTS 21 /* max # of slots needed for short and long names */
#define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */
#define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */
/* media of boot sector */
#define FAT_VALID_MEDIA(x) ((0xF8 <= (x) && (x) <= 0xFF) || (x) == 0xF0)
#define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \
MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x))
/* maximum number of clusters */
#define MAX_FAT12 0xFF4
#define MAX_FAT16 0xFFF4
#define MAX_FAT32 0x0FFFFFF6
#define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \
MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12)
/* bad cluster mark */
#define BAD_FAT12 0xFF7
#define BAD_FAT16 0xFFF7
#define BAD_FAT32 0x0FFFFFF7
#define BAD_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? BAD_FAT32 : \
MSDOS_SB(s)->fat_bits == 16 ? BAD_FAT16 : BAD_FAT12)
/* standard EOF */
#define EOF_FAT12 0xFFF
#define EOF_FAT16 0xFFFF
#define EOF_FAT32 0x0FFFFFFF
#define EOF_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? EOF_FAT32 : \
MSDOS_SB(s)->fat_bits == 16 ? EOF_FAT16 : EOF_FAT12)
#define FAT_ENT_FREE (0)
#define FAT_ENT_BAD (BAD_FAT32)
#define FAT_ENT_EOF (EOF_FAT32)
#define FAT_FSINFO_SIG1 0x41615252
#define FAT_FSINFO_SIG2 0x61417272
#define IS_FSINFO(x) (CF_LE_L((x)->signature1) == FAT_FSINFO_SIG1 \
&& CF_LE_L((x)->signature2) == FAT_FSINFO_SIG2)
/*
* ioctl commands
*/
#define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct dirent [2])
#define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct dirent [2])
/*
* vfat shortname flags
*/
#define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */
#define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */
#define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */
#define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */
#define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */
/*
* Conversion from and to little-endian byte order. (no-op on i386/i486)
*
* Naming: Ca_b_c, where a: F = from, T = to, b: LE = little-endian,
* BE = big-endian, c: W = word (16 bits), L = longword (32 bits)
*/
#define CF_LE_W(v) le16_to_cpu(v)
#define CF_LE_L(v) le32_to_cpu(v)
#define CT_LE_W(v) cpu_to_le16(v)
#define CT_LE_L(v) cpu_to_le32(v)
struct fat_boot_sector {
__u8 ignored[3]; /* Boot strap short or near jump */
__u8 system_id[8]; /* Name - can be used to special case
partition manager volumes */
__u8 sector_size[2]; /* bytes per logical sector */
__u8 sec_per_clus; /* sectors/cluster */
__u16 reserved; /* reserved sectors */
__u8 fats; /* number of FATs */
__u8 dir_entries[2]; /* root directory entries */
__u8 sectors[2]; /* number of sectors */
__u8 media; /* media code */
__u16 fat_length; /* sectors/FAT */
__u16 secs_track; /* sectors per track */
__u16 heads; /* number of heads */
__u32 hidden; /* hidden sectors (unused) */
__u32 total_sect; /* number of sectors (if sectors == 0) */
/* The following fields are only used by FAT32 */
__u32 fat32_length; /* sectors/FAT */
__u16 flags; /* bit 8: fat mirroring, low 4: active fat */
__u8 version[2]; /* major, minor filesystem version */
__u32 root_cluster; /* first cluster in root directory */
__u16 info_sector; /* filesystem info sector */
__u16 backup_boot; /* backup boot sector */
__u16 reserved2[6]; /* Unused */
};
struct fat_boot_fsinfo {
__u32 signature1; /* 0x41615252L */
__u32 reserved1[120]; /* Nothing as far as I can tell */
__u32 signature2; /* 0x61417272L */
__u32 free_clusters; /* Free cluster count. -1 if unknown */
__u32 next_cluster; /* Most recently allocated cluster */
__u32 reserved2[4];
};
struct msdos_dir_entry {
__u8 name[8],ext[3]; /* name and extension */
__u8 attr; /* attribute bits */
__u8 lcase; /* Case for base and extension */
__u8 ctime_ms; /* Creation time, milliseconds */
__u16 ctime; /* Creation time */
__u16 cdate; /* Creation date */
__u16 adate; /* Last access date */
__u16 starthi; /* High 16 bits of cluster in FAT32 */
__u16 time,date,start;/* time, date and first cluster */
__u32 size; /* file size (in bytes) */
};
/* Up to 13 characters of the name */
struct msdos_dir_slot {
__u8 id; /* sequence number for slot */
__u8 name0_4[10]; /* first 5 characters in name */
__u8 attr; /* attribute byte */
__u8 reserved; /* always 0 */
__u8 alias_checksum; /* checksum for 8.3 alias */
__u8 name5_10[12]; /* 6 more characters in name */
__u16 start; /* starting cluster number, 0 in long slots */
__u8 name11_12[4]; /* last 2 characters in name */
};
struct vfat_slot_info {
int long_slots; /* number of long slots in filename */
loff_t longname_offset; /* dir offset for longname start */
loff_t i_pos; /* on-disk position of directory entry */
};
#ifdef __KERNEL__
#include <linux/buffer_head.h>
#include <linux/string.h>
#include <linux/nls.h>
#include <linux/msdos_fs_i.h>
#include <linux/msdos_fs_sb.h>
static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb)
{
return sb->s_fs_info;
}
static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
{
return container_of(inode, struct msdos_inode_info, vfs_inode);
}
static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len)
{
#ifdef __BIG_ENDIAN
while (len--) {
*dst++ = src[0] | (src[1] << 8);
src += 2;
}
#else
memcpy(dst, src, len * 2);
#endif
}
static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len)
{
#ifdef __BIG_ENDIAN
while (len--) {
dst[0] = *src & 0x00FF;
dst[1] = (*src & 0xFF00) >> 8;
dst += 2;
src++;
}
#else
memcpy(dst, src, len * 2);
#endif
}
/* fat/cache.c */
extern int fat_access(struct super_block *sb, int nr, int new_value);
extern int __fat_access(struct super_block *sb, int nr, int new_value);
extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys);
extern void fat_cache_init(struct super_block *sb);
extern void fat_cache_lookup(struct inode *inode, int cluster, int *f_clu,
int *d_clu);
extern void fat_cache_add(struct inode *inode, int f_clu, int d_clu);
extern void fat_cache_inval_inode(struct inode *inode);
extern int fat_get_cluster(struct inode *inode, int cluster,
int *fclus, int *dclus);
extern int fat_free(struct inode *inode, int skip);
/* fat/dir.c */
extern struct file_operations fat_dir_operations;
extern int fat_search_long(struct inode *inode, const unsigned char *name,
int name_len, int anycase,
loff_t *spos, loff_t *lpos);
extern int fat_readdir(struct file *filp, void *dirent, filldir_t filldir);
extern int fat_dir_ioctl(struct inode * inode, struct file * filp,
unsigned int cmd, unsigned long arg);
extern int fat_add_entries(struct inode *dir, int slots, struct buffer_head **bh,
struct msdos_dir_entry **de, loff_t *i_pos);
extern int fat_new_dir(struct inode *dir, struct inode *parent, int is_vfat);
extern int fat_dir_empty(struct inode *dir);
extern int fat_subdirs(struct inode *dir);
extern int fat_scan(struct inode *dir, const unsigned char *name,
struct buffer_head **res_bh,
struct msdos_dir_entry **res_de, loff_t *i_pos);
/* fat/file.c */
extern struct file_operations fat_file_operations;
extern struct inode_operations fat_file_inode_operations;
extern int fat_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create);
extern void fat_truncate(struct inode *inode);
/* fat/inode.c */
extern void fat_hash_init(void);
extern void fat_attach(struct inode *inode, loff_t i_pos);
extern void fat_detach(struct inode *inode);
extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos);
extern struct inode *fat_build_inode(struct super_block *sb,
struct msdos_dir_entry *de, loff_t i_pos, int *res);
extern void fat_delete_inode(struct inode *inode);
extern void fat_clear_inode(struct inode *inode);
extern void fat_put_super(struct super_block *sb);
int fat_fill_super(struct super_block *sb, void *data, int silent,
struct inode_operations *fs_dir_inode_ops, int isvfat);
extern int fat_statfs(struct super_block *sb, struct kstatfs *buf);
extern void fat_write_inode(struct inode *inode, int wait);
extern int fat_notify_change(struct dentry * dentry, struct iattr * attr);
/* fat/misc.c */
extern void fat_fs_panic(struct super_block *s, const char *fmt, ...);
extern void lock_fat(struct super_block *sb);
extern void unlock_fat(struct super_block *sb);
extern void fat_clusters_flush(struct super_block *sb);
extern int fat_add_cluster(struct inode *inode);
extern struct buffer_head *fat_extend_dir(struct inode *inode);
extern int date_dos2unix(unsigned short time, unsigned short date);
extern void fat_date_unix2dos(int unix_date, unsigned short *time,
unsigned short *date);
extern int fat__get_entry(struct inode *dir, loff_t *pos,
struct buffer_head **bh,
struct msdos_dir_entry **de, loff_t *i_pos);
static __inline__ int fat_get_entry(struct inode *dir, loff_t *pos,
struct buffer_head **bh,
struct msdos_dir_entry **de, loff_t *i_pos)
{
/* Fast stuff first */
if (*bh && *de &&
(*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
*pos += sizeof(struct msdos_dir_entry);
(*de)++;
(*i_pos)++;
return 0;
}
return fat__get_entry(dir, pos, bh, de, i_pos);
}
#endif /* __KERNEL__ */
#endif
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