| Current File : //usr/include/linux/msdos_fs.h |
#ifndef _LINUX_MSDOS_FS_H
#define _LINUX_MSDOS_FS_H
#include <linux/types.h>
#include <linux/magic.h>
#include <asm/byteorder.h>
/*
* The MS-DOS filesystem constants/structures
*/
#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_LONGNAME 256 /* maximum name length */
#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)
#define MSDOS_ROOT_INO 1 /* The root inode number */
#define MSDOS_FSINFO_INO 2 /* Used for managing the FSINFO block */
#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)
#define FAT_LFN_LEN 255 /* maximum long name length */
#define MSDOS_NAME 11 /* maximum name length */
#define MSDOS_SLOTS 21 /* max # of slots for short and long names */
#define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */
#define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */
#define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \
MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x))
/* start of data cluster's entry (number of reserved clusters) */
#define FAT_START_ENT 2
/* 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
/* standard EOF */
#define EOF_FAT12 0xFFF
#define EOF_FAT16 0xFFFF
#define EOF_FAT32 0x0FFFFFFF
#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) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \
&& le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2)
#define FAT_STATE_DIRTY 0x01
struct __fat_dirent {
long d_ino;
__kernel_off_t d_off;
unsigned short d_reclen;
char d_name[256]; /* We must not include limits.h! */
};
/*
* ioctl commands
*/
#define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct __fat_dirent[2])
#define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct __fat_dirent[2])
/* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */
#define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32)
#define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32)
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 */
__le16 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 */
__le16 fat_length; /* sectors/FAT */
__le16 secs_track; /* sectors per track */
__le16 heads; /* number of heads */
__le32 hidden; /* hidden sectors (unused) */
__le32 total_sect; /* number of sectors (if sectors == 0) */
union {
struct {
/* Extended BPB Fields for FAT16 */
__u8 drive_number; /* Physical drive number */
__u8 state; /* undocumented, but used
for mount state. */
/* other fiealds are not added here */
} fat16;
struct {
/* only used by FAT32 */
__le32 length; /* sectors/FAT */
__le16 flags; /* bit 8: fat mirroring,
low 4: active fat */
__u8 version[2]; /* major, minor filesystem
version */
__le32 root_cluster; /* first cluster in
root directory */
__le16 info_sector; /* filesystem info sector */
__le16 backup_boot; /* backup boot sector */
__le16 reserved2[6]; /* Unused */
/* Extended BPB Fields for FAT32 */
__u8 drive_number; /* Physical drive number */
__u8 state; /* undocumented, but used
for mount state. */
/* other fiealds are not added here */
} fat32;
};
};
struct fat_boot_fsinfo {
__le32 signature1; /* 0x41615252L */
__le32 reserved1[120]; /* Nothing as far as I can tell */
__le32 signature2; /* 0x61417272L */
__le32 free_clusters; /* Free cluster count. -1 if unknown */
__le32 next_cluster; /* Most recently allocated cluster */
__le32 reserved2[4];
};
struct msdos_dir_entry {
__u8 name[MSDOS_NAME];/* name and extension */
__u8 attr; /* attribute bits */
__u8 lcase; /* Case for base and extension */
__u8 ctime_cs; /* Creation time, centiseconds (0-199) */
__le16 ctime; /* Creation time */
__le16 cdate; /* Creation date */
__le16 adate; /* Last access date */
__le16 starthi; /* High 16 bits of cluster in FAT32 */
__le16 time,date,start;/* time, date and first cluster */
__le32 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 */
__le16 start; /* starting cluster number, 0 in long slots */
__u8 name11_12[4]; /* last 2 characters in name */
};
#endif /* _LINUX_MSDOS_FS_H */