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#ifndef _LINUX_MSDOS_FS_H
#define _LINUX_MSDOS_FS_H
/*
* The MS-DOS filesystem constants/structures
*/
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/fd.h>
#define MSDOS_ROOT_INO 1 /* == MINIX_ROOT_INO */
#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_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */
#define MSDOS_SUPER_MAGIC 0x4d44 /* MD */
#define FAT_CACHE 8 /* FAT cache size */
#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 */
#define ATTR_NONE 0 /* no attribute bits */
#define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN)
/* attribute bits that are copied "as is" */
#define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */
#define IS_FREE(n) (!*(n) || *(unsigned char *) (n) == DELETED_FLAG || \
*(unsigned char *) (n) == FD_FILL_BYTE)
#define MSDOS_VALID_MODE (S_IFREG | S_IFDIR | S_IRWXU | S_IRWXG | S_IRWXO)
/* valid file mode bits */
#define MSDOS_SB(s) (&((s)->u.msdos_sb))
#define MSDOS_I(i) (&((i)->u.msdos_i))
#define MSDOS_NAME 11 /* maximum name length */
#define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */
#define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */
#define MSDOS_FAT12 4078 /* maximum number of clusters in a 12 bit FAT */
/*
* 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) (v)
#define CF_LE_L(v) (v)
#define CT_LE_W(v) (v)
#define CT_LE_L(v) (v)
struct msdos_boot_sector {
char ignored[3]; /* Boot strap short or near jump */
char system_id[8]; /* Name - can be used to special case
partition manager volumes */
unsigned char sector_size[2];/* bytes per logical sector */
unsigned char cluster_size; /* sectors/cluster */
unsigned short reserved; /* reserved sectors */
unsigned char fats; /* number of FATs */
unsigned char dir_entries[2];/* root directory entries */
unsigned char sectors[2]; /* number of sectors */
unsigned char media; /* media code (unused) */
unsigned short fat_length; /* sectors/FAT */
unsigned short secs_track; /* sectors per track */
unsigned short heads; /* number of heads */
unsigned long hidden; /* hidden sectors (unused) */
unsigned long total_sect; /* number of sectors (if sectors == 0) */
};
struct msdos_dir_entry {
char name[8],ext[3]; /* name and extension */
unsigned char attr; /* attribute bits */
char unused[10];
unsigned short time,date,start; /* time, date and first cluster */
unsigned long size; /* file size (in bytes) */
};
struct fat_cache {
int device; /* device number. 0 means unused. */
int ino; /* inode number. */
int file_cluster; /* cluster number in the file. */
int disk_cluster; /* cluster number on disk. */
struct fat_cache *next; /* next cache entry */
};
/* Determine whether this FS has kB-aligned data. */
#define MSDOS_CAN_BMAP(mib) (!(((mib)->cluster_size & 1) || \
((mib)->data_start & 1)))
/* 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)
#ifdef __KERNEL__
static inline struct buffer_head *msdos_sread(int dev,int sector)
{
return bread(dev,sector,SECTOR_SIZE);
}
/* misc.c */
extern void fs_panic(struct super_block *s,char *msg);
extern int is_binary(char conversion,char *extension);
extern void lock_creation(void);
extern void unlock_creation(void);
extern void lock_fat(struct super_block *sb);
extern void unlock_fat(struct super_block *sb);
extern int msdos_add_cluster(struct inode *inode);
extern int date_dos2unix(unsigned short time,unsigned short date);
extern void date_unix2dos(int unix_date,unsigned short *time,
unsigned short *date);
extern int msdos_get_entry(struct inode *dir,loff_t *pos,struct buffer_head **bh,
struct msdos_dir_entry **de);
extern int msdos_scan(struct inode *dir,char *name,struct buffer_head **res_bh,
struct msdos_dir_entry **res_de,int *ino);
extern int msdos_parent_ino(struct inode *dir,int locked);
extern int msdos_subdirs(struct inode *dir);
/* fat.c */
extern int fat_access(struct super_block *sb,int nr,int new_value);
extern int msdos_smap(struct inode *inode,int sector);
extern int fat_free(struct inode *inode,int skip);
extern void cache_init(void);
void cache_lookup(struct inode *inode,int cluster,int *f_clu,int *d_clu);
void cache_add(struct inode *inode,int f_clu,int d_clu);
void cache_inval_inode(struct inode *inode);
void cache_inval_dev(int device);
int get_cluster(struct inode *inode,int cluster);
/* namei.c */
extern int msdos_lookup(struct inode *dir,const char *name,int len,
struct inode **result);
extern int msdos_create(struct inode *dir,const char *name,int len,int mode,
struct inode **result);
extern int msdos_mkdir(struct inode *dir,const char *name,int len,int mode);
extern int msdos_rmdir(struct inode *dir,const char *name,int len);
extern int msdos_unlink(struct inode *dir,const char *name,int len);
extern int msdos_unlink_umsdos(struct inode *dir,const char *name,int len);
extern int msdos_rename(struct inode *old_dir,const char *old_name,int old_len,
struct inode *new_dir,const char *new_name,int new_len);
/* inode.c */
extern void msdos_put_inode(struct inode *inode);
extern void msdos_put_super(struct super_block *sb);
extern struct super_block *msdos_read_super(struct super_block *s,
void *data,int);
extern void msdos_statfs(struct super_block *sb,struct statfs *buf);
extern int msdos_bmap(struct inode *inode,int block);
extern void msdos_read_inode(struct inode *inode);
extern void msdos_write_inode(struct inode *inode);
extern int msdos_notify_change(struct inode *,struct iattr *);
/* dir.c */
extern struct inode_operations msdos_dir_inode_operations;
extern int msdos_readdir (struct inode *inode, struct file *filp,
struct dirent *dirent, int count);
/* file.c */
extern struct inode_operations msdos_file_inode_operations;
extern int msdos_file_read(struct inode *, struct file *, char *, int);
extern int msdos_file_write(struct inode *, struct file *, char *, int);
extern struct inode_operations msdos_file_inode_operations_no_bmap;
extern void msdos_truncate(struct inode *inode);
/* mmap.c */
extern int msdos_mmap(struct inode *, struct file *, struct vm_area_struct *);
#endif /* __KERNEL__ */
#endif
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