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#ifndef _FAT_H
#define _FAT_H
#include <linux/buffer_head.h>
#include <linux/string.h>
#include <linux/nls.h>
#include <linux/fs.h>
#include <linux/mutex.h>
#include <linux/ratelimit.h>
#include <linux/msdos_fs.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 */
#define FAT_ERRORS_CONT 1 /* ignore error and continue */
#define FAT_ERRORS_PANIC 2 /* panic on error */
#define FAT_ERRORS_RO 3 /* remount r/o on error */
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 char errors; /* On error: continue, panic, remount-ro */
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 */
rodir:1, /* allow ATTR_RO for directory */
discard:1; /* Issue discard requests on deletions */
};
#define FAT_HASH_BITS 8
#define FAT_HASH_SIZE (1UL << FAT_HASH_BITS)
/*
* 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;
struct inode *fat_inode;
struct ratelimit_state ratelimit;
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;
/* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */
loff_t mmu_private; /* physically allocated size */
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 rw_semaphore truncate_lock; /* protect bmap against truncate */
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);
}
/*
* If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to
* save ATTR_RO instead of ->i_mode.
*
* If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
* bit, it's just used as flag for app.
*/
static inline int fat_mode_can_hold_ro(struct inode *inode)
{
struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
umode_t mask;
if (S_ISDIR(inode->i_mode)) {
if (!sbi->options.rodir)
return 0;
mask = ~sbi->options.fs_dmask;
} else
mask = ~sbi->options.fs_fmask;
if (!(mask & S_IWUGO))
return 0;
return 1;
}
/* Convert attribute bits and a mask to the UNIX mode. */
static inline umode_t fat_make_mode(struct msdos_sb_info *sbi,
u8 attrs, umode_t mode)
{
if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir))
mode &= ~S_IWUGO;
if (attrs & ATTR_DIR)
return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
else
return (mode & ~sbi->options.fs_fmask) | S_IFREG;
}
/* Return the FAT attribute byte for this inode */
static inline u8 fat_make_attrs(struct inode *inode)
{
u8 attrs = MSDOS_I(inode)->i_attrs;
if (S_ISDIR(inode->i_mode))
attrs |= ATTR_DIR;
if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO))
attrs |= ATTR_RO;
return attrs;
}
static inline void fat_save_attrs(struct inode *inode, u8 attrs)
{
if (fat_mode_can_hold_ro(inode))
MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED;
else
MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO);
}
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
}
/* fat/cache.c */
extern void fat_cache_inval_inode(struct inode *inode);
extern int fat_get_cluster
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