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DEFINITIONS
This source file includes following definitions.
- MSDOS_SB
- MSDOS_I
- fat_attr
- fat_checksum
- fat_clus_to_blknr
- fat16_towchar
- fatwchar_to16
- fat_valid_media
- fatent_init
- fatent_set_entry
- fatent_brelse
#ifndef _LINUX_MSDOS_FS_H
#define _LINUX_MSDOS_FS_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 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 /* == 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))
#define MSDOS_NAME 11 /* maximum name length */
#define MSDOS_LONGNAME 256 /* 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)
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) */
/* The following fields are only used by FAT32 */
__le32 fat32_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 */
};
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 */
};
#ifdef __KERNEL__
#include <linux/buffer_head.h>
#include <linux/string.h>
#include <linux/nls.h>
#include <linux/fs.h>
#include <linux/mutex.h>
/*
* 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 */
struct fat_mount_options {
uid_t fs_uid;
gid_t fs_gid;
unsigned short fs_fmask;
unsigned short fs_dmask;
unsigned short codepage; /* Codepage for shortname conversions */
char *iocharset; /* Charset used for filename input/display */
unsigned short shortname; /* flags for shortname display/create rule */
unsigned char name_check; /* r = relaxed, n = normal, s = strict */
unsigned short allow_utime;/* permission for setting the [am]time */
unsigned quiet:1, /* set = fake successful chmods and chowns */
showexec:1, /* set = only set x bit for com/exe/bat */
sys_immutable:1, /* set = system files are immutable */
dotsOK:1, /* set = hidden and system files are named '.filename' */
isvfat:1, /* 0=no vfat long filename support, 1=vfat support */
utf8:1, /* Use of UTF-8 character set (Default) */
unicode_xlate:1, /* create escape sequences for unhandled Unicode */
numtail:1, /* Does first alias have a numeric '~1' type tail? */
flush:1, /* write things quickly */
nocase:1, /* Does this need case conversion? 0=need case conversion*/
usefree:1, /* Use free_clusters for FAT32 */
tz_utc:1; /* Filesystem timestamps are in UTC */
};
#define FAT_HASH_BITS 8
#define FAT_HASH_SIZE (1UL << FAT_HASH_BITS)
#define FAT_HASH_MASK (FAT_HASH_SIZE-1)
/*
* MS-DOS file system in-core superblock data
*/
struct msdos_sb_info {
unsigned short sec_per_clus; /* sectors/cluster */
unsigned short cluster_bits; /* log2(cluster_size) */
unsigned int cluster_size; /* cluster size */
unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */
unsigned short fat_start;
unsigned long fat_length; /* FAT start & length (sec.) */
unsigned long dir_start;
unsigned short dir_entries; /* root dir start & entries */
unsigned long data_start; /* first data sector */
unsigned long max_cluster; /* maximum cluster number */
unsigned long root_cluster; /* first cluster of the root directory */
unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */
struct mutex fat_lock;
unsigned int prev_free; /* previously allocated cluster number */
unsigned int free_clusters; /* -1 if undefined */
unsigned int free_clus_valid; /* is free_clusters valid? */
struct fat_mount_options options;
struct nls_table *nls_disk; /* Codepage used on disk */
struct nls_table *nls_io; /* Charset used for input and display */
const void *dir_ops; /* Opaque; default directory operations */
int dir_per_block; /* dir entries per block */
int dir_per_block_bits; /* log2(dir_per_block) */
int fatent_shift;
struct fatent_operations *fatent_ops;
spinlock_t inode_hash_lock;
struct hlist_head inode_hashtable[FAT_HASH_SIZE];
};
#define FAT_CACHE_VALID 0 /* special case for valid cache */
/*
* MS-DOS file system inode data in memory
*/
struct msdos_inode_info {
spinlock_t cache_lru_lock;
struct list_head cache_lru;
int nr_caches;
/* for avoiding the race between fat_free() and fat_get_cluster() */
unsigned int cache_valid_id;
loff_t mmu_private;
int i_start; /* first cluster or 0 */
int i_logstart; /* logical first cluster */
int i_attrs; /* unused attribute bits */
loff_t i_pos; /* on-disk position of directory entry or 0 */
struct hlist_node i_fat_hash; /* hash by i_location */
struct inode vfs_inode;
};
struct fat_slot_info {
loff_t i_pos; /* on-disk position of directory entry */
loff_t slot_off; /* offset for slot or de start */
int nr_slots; /* number of slots + 1(de) in filename */
struct msdos_dir_entry *de;
struct buffer_head *bh;
};
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);
}
/* Return the FAT attribute byte for this inode */
static inline u8 fat_attr(struct inode *inode)
{
return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) |
(S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) |
MSDOS_I(inode)->i_attrs;
}
static inline unsigned char fat_checksum(const __u8 *name)
{
unsigned char s = name[0];
s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2];
s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4];
s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6];
s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8];
s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10];
return s;
}
static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus)
{
return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus
+ sbi->data_start;
}
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
}
/* media of boot sector */
static inline int fat_valid_media(u8 media)
{
return 0xf8 <= media || media == 0xf0;
}
/* fat/cache.c */
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_bmap(struct inode *inode, sector_t sector, sector_t *phys,
unsigned long *mapped_blocks);
/* fat/dir.c */
extern const struct file_operations fat_dir_operations;
extern int fat_search_long(struct inode *inode, const unsigned char *name,
int name_len, struct fat_slot_info *sinfo);
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 fat_slot_info *sinfo);
extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
struct msdos_dir_entry **de, loff_t *i_pos);
extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts);
extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
struct fat_slot_info *sinfo);
extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo);
/* fat/fatent.c */
struct fat_entry {
int entry;
union {
u8 *ent12_p[2];
__le16 *ent16_p;
__le32 *ent32_p;
} u;
int nr_bhs;
struct buffer_head *bhs[2];
};
static inline void fatent_init(struct fat_entry *fatent)
{
fatent->nr_bhs = 0;
fatent->entry = 0;
fatent->u.ent32_p = NULL;
fatent->bhs[0] = fatent->bhs[1] = NULL;
}
static inline void fatent_set_entry(struct fat_entry *fatent, int entry)
{
fatent->entry = entry;
fatent->u.ent32_p = NULL;
}
static inline void fatent_brelse(struct fat_entry *fatent)
{
int i;
fatent->u.ent32_p = NULL;
for (i = 0; i < fatent->nr_bhs; i++)
brelse(fatent->bhs[i]);
fatent->nr_bhs = 0;
fatent->bhs[0] = fatent->bhs[1] = NULL;
}
extern void fat_ent_access_init(struct super_block *sb);
extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent,
int entry);
extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent,
int new, int wait);
extern int fat_alloc_clusters(struct inode *inode, int *cluster,
int nr_cluster);
extern int fat_free_clusters(struct inode *inode, int cluster);
extern int fat_count_free_clusters(struct super_block *sb);
/* fat/file.c */
extern int fat_generic_ioctl(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg);
extern const struct file_operations fat_file_operations;
extern const struct inode_operations fat_file_inode_operations;
extern int fat_setattr(struct dentry * dentry, struct iattr * attr);
extern void fat_truncate(struct inode *inode);
extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat);
/* fat/inode.c */
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);
extern int fat_sync_inode(struct inode *inode);
extern int fat_fill_super(struct super_block *sb, void *data, int silent,
const struct inode_operations *fs_dir_inode_ops, int isvfat);
extern int fat_flush_inodes(struct super_block *sb, struct inode *i1,
struct inode *i2);
/* fat/misc.c */
extern void fat_fs_panic(struct super_block *s, const char *fmt, ...);
extern void fat_clusters_flush(struct super_block *sb);
extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
extern int date_dos2unix(unsigned short time, unsigned short date, int tz_utc);
extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date,
int tz_utc);
extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs);
int fat_cache_init(void);
void fat_cache_destroy(void);
#endif /* __KERNEL__ */
#endif