4 #include <linux/buffer_head.h>
5 #include <linux/string.h>
8 #include <linux/hash.h>
9 #include <linux/mutex.h>
10 #include <linux/ratelimit.h>
11 #include <linux/msdos_fs.h>
14 * vfat shortname flags
16 #define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */
17 #define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */
18 #define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */
19 #define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */
20 #define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */
22 #define FAT_ERRORS_CONT 1 /* ignore error and continue */
23 #define FAT_ERRORS_PANIC 2 /* panic on error */
24 #define FAT_ERRORS_RO 3 /* remount r/o on error */
26 struct fat_mount_options
{
29 unsigned short fs_fmask
;
30 unsigned short fs_dmask
;
31 unsigned short codepage
; /* Codepage for shortname conversions */
32 char *iocharset
; /* Charset used for filename input/display */
33 unsigned short shortname
; /* flags for shortname display/create rule */
34 unsigned char name_check
; /* r = relaxed, n = normal, s = strict */
35 unsigned char errors
; /* On error: continue, panic, remount-ro */
36 unsigned short allow_utime
;/* permission for setting the [am]time */
37 unsigned quiet
:1, /* set = fake successful chmods and chowns */
38 showexec
:1, /* set = only set x bit for com/exe/bat */
39 sys_immutable
:1, /* set = system files are immutable */
40 dotsOK
:1, /* set = hidden and system files are named '.filename' */
41 isvfat
:1, /* 0=no vfat long filename support, 1=vfat support */
42 utf8
:1, /* Use of UTF-8 character set (Default) */
43 unicode_xlate
:1, /* create escape sequences for unhandled Unicode */
44 numtail
:1, /* Does first alias have a numeric '~1' type tail? */
45 flush
:1, /* write things quickly */
46 nocase
:1, /* Does this need case conversion? 0=need case conversion*/
47 usefree
:1, /* Use free_clusters for FAT32 */
48 tz_utc
:1, /* Filesystem timestamps are in UTC */
49 rodir
:1, /* allow ATTR_RO for directory */
50 discard
:1, /* Issue discard requests on deletions */
51 nfs
:1; /* Do extra work needed for NFS export */
54 #define FAT_HASH_BITS 8
55 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS)
58 * MS-DOS file system in-core superblock data
60 struct msdos_sb_info
{
61 unsigned short sec_per_clus
; /* sectors/cluster */
62 unsigned short cluster_bits
; /* log2(cluster_size) */
63 unsigned int cluster_size
; /* cluster size */
64 unsigned char fats
,fat_bits
; /* number of FATs, FAT bits (12 or 16) */
65 unsigned short fat_start
;
66 unsigned long fat_length
; /* FAT start & length (sec.) */
67 unsigned long dir_start
;
68 unsigned short dir_entries
; /* root dir start & entries */
69 unsigned long data_start
; /* first data sector */
70 unsigned long max_cluster
; /* maximum cluster number */
71 unsigned long root_cluster
; /* first cluster of the root directory */
72 unsigned long fsinfo_sector
; /* sector number of FAT32 fsinfo */
73 struct mutex fat_lock
;
74 unsigned int prev_free
; /* previously allocated cluster number */
75 unsigned int free_clusters
; /* -1 if undefined */
76 unsigned int free_clus_valid
; /* is free_clusters valid? */
77 struct fat_mount_options options
;
78 struct nls_table
*nls_disk
; /* Codepage used on disk */
79 struct nls_table
*nls_io
; /* Charset used for input and display */
80 const void *dir_ops
; /* Opaque; default directory operations */
81 int dir_per_block
; /* dir entries per block */
82 int dir_per_block_bits
; /* log2(dir_per_block) */
85 struct fatent_operations
*fatent_ops
;
86 struct inode
*fat_inode
;
87 struct inode
*fsinfo_inode
;
89 struct ratelimit_state ratelimit
;
91 spinlock_t inode_hash_lock
;
92 struct hlist_head inode_hashtable
[FAT_HASH_SIZE
];
94 spinlock_t dir_hash_lock
;
95 struct hlist_head dir_hashtable
[FAT_HASH_SIZE
];
98 #define FAT_CACHE_VALID 0 /* special case for valid cache */
101 * MS-DOS file system inode data in memory
103 struct msdos_inode_info
{
104 spinlock_t cache_lru_lock
;
105 struct list_head cache_lru
;
107 /* for avoiding the race between fat_free() and fat_get_cluster() */
108 unsigned int cache_valid_id
;
110 /* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */
111 loff_t mmu_private
; /* physically allocated size */
113 int i_start
; /* first cluster or 0 */
114 int i_logstart
; /* logical first cluster */
115 int i_attrs
; /* unused attribute bits */
116 loff_t i_pos
; /* on-disk position of directory entry or 0 */
117 struct hlist_node i_fat_hash
; /* hash by i_location */
118 struct hlist_node i_dir_hash
; /* hash by i_logstart */
119 struct rw_semaphore truncate_lock
; /* protect bmap against truncate */
120 struct inode vfs_inode
;
123 struct fat_slot_info
{
124 loff_t i_pos
; /* on-disk position of directory entry */
125 loff_t slot_off
; /* offset for slot or de start */
126 int nr_slots
; /* number of slots + 1(de) in filename */
127 struct msdos_dir_entry
*de
;
128 struct buffer_head
*bh
;
131 static inline struct msdos_sb_info
*MSDOS_SB(struct super_block
*sb
)
133 return sb
->s_fs_info
;
136 static inline struct msdos_inode_info
*MSDOS_I(struct inode
*inode
)
138 return container_of(inode
, struct msdos_inode_info
, vfs_inode
);
142 * If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to
143 * save ATTR_RO instead of ->i_mode.
145 * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
146 * bit, it's just used as flag for app.
148 static inline int fat_mode_can_hold_ro(struct inode
*inode
)
150 struct msdos_sb_info
*sbi
= MSDOS_SB(inode
->i_sb
);
153 if (S_ISDIR(inode
->i_mode
)) {
154 if (!sbi
->options
.rodir
)
156 mask
= ~sbi
->options
.fs_dmask
;
158 mask
= ~sbi
->options
.fs_fmask
;
160 if (!(mask
& S_IWUGO
))
165 /* Convert attribute bits and a mask to the UNIX mode. */
166 static inline umode_t
fat_make_mode(struct msdos_sb_info
*sbi
,
167 u8 attrs
, umode_t mode
)
169 if (attrs
& ATTR_RO
&& !((attrs
& ATTR_DIR
) && !sbi
->options
.rodir
))
172 if (attrs
& ATTR_DIR
)
173 return (mode
& ~sbi
->options
.fs_dmask
) | S_IFDIR
;
175 return (mode
& ~sbi
->options
.fs_fmask
) | S_IFREG
;
178 /* Return the FAT attribute byte for this inode */
179 static inline u8
fat_make_attrs(struct inode
*inode
)
181 u8 attrs
= MSDOS_I(inode
)->i_attrs
;
182 if (S_ISDIR(inode
->i_mode
))
184 if (fat_mode_can_hold_ro(inode
) && !(inode
->i_mode
& S_IWUGO
))
189 static inline void fat_save_attrs(struct inode
*inode
, u8 attrs
)
191 if (fat_mode_can_hold_ro(inode
))
192 MSDOS_I(inode
)->i_attrs
= attrs
& ATTR_UNUSED
;
194 MSDOS_I(inode
)->i_attrs
= attrs
& (ATTR_UNUSED
| ATTR_RO
);
197 static inline unsigned char fat_checksum(const __u8
*name
)
199 unsigned char s
= name
[0];
200 s
= (s
<<7) + (s
>>1) + name
[1]; s
= (s
<<7) + (s
>>1) + name
[2];
201 s
= (s
<<7) + (s
>>1) + name
[3]; s
= (s
<<7) + (s
>>1) + name
[4];
202 s
= (s
<<7) + (s
>>1) + name
[5]; s
= (s
<<7) + (s
>>1) + name
[6];
203 s
= (s
<<7) + (s
>>1) + name
[7]; s
= (s
<<7) + (s
>>1) + name
[8];
204 s
= (s
<<7) + (s
>>1) + name
[9]; s
= (s
<<7) + (s
>>1) + name
[10];
208 static inline sector_t
fat_clus_to_blknr(struct msdos_sb_info
*sbi
, int clus
)
210 return ((sector_t
)clus
- FAT_START_ENT
) * sbi
->sec_per_clus
214 static inline void fat16_towchar(wchar_t *dst
, const __u8
*src
, size_t len
)
218 *dst
++ = src
[0] | (src
[1] << 8);
222 memcpy(dst
, src
, len
* 2);
226 static inline int fat_get_start(const struct msdos_sb_info
*sbi
,
227 const struct msdos_dir_entry
*de
)
229 int cluster
= le16_to_cpu(de
->start
);
230 if (sbi
->fat_bits
== 32)
231 cluster
|= (le16_to_cpu(de
->starthi
) << 16);
235 static inline void fat_set_start(struct msdos_dir_entry
*de
, int cluster
)
237 de
->start
= cpu_to_le16(cluster
);
238 de
->starthi
= cpu_to_le16(cluster
>> 16);
241 static inline void fatwchar_to16(__u8
*dst
, const wchar_t *src
, size_t len
)
245 dst
[0] = *src
& 0x00FF;
246 dst
[1] = (*src
& 0xFF00) >> 8;
251 memcpy(dst
, src
, len
* 2);
256 extern void fat_cache_inval_inode(struct inode
*inode
);
257 extern int fat_get_cluster(struct inode
*inode
, int cluster
,
258 int *fclus
, int *dclus
);
259 extern int fat_bmap(struct inode
*inode
, sector_t sector
, sector_t
*phys
,
260 unsigned long *mapped_blocks
, int create
);
263 extern const struct file_operations fat_dir_operations
;
264 extern int fat_search_long(struct inode
*inode
, const unsigned char *name
,
265 int name_len
, struct fat_slot_info
*sinfo
);
266 extern int fat_dir_empty(struct inode
*dir
);
267 extern int fat_subdirs(struct inode
*dir
);
268 extern int fat_scan(struct inode
*dir
, const unsigned char *name
,
269 struct fat_slot_info
*sinfo
);
270 extern int fat_get_dotdot_entry(struct inode
*dir
, struct buffer_head
**bh
,
271 struct msdos_dir_entry
**de
);
272 extern int fat_alloc_new_dir(struct inode
*dir
, struct timespec
*ts
);
273 extern int fat_add_entries(struct inode
*dir
, void *slots
, int nr_slots
,
274 struct fat_slot_info
*sinfo
);
275 extern int fat_remove_entries(struct inode
*dir
, struct fat_slot_info
*sinfo
);
286 struct buffer_head
*bhs
[2];
287 struct inode
*fat_inode
;
290 static inline void fatent_init(struct fat_entry
*fatent
)
294 fatent
->u
.ent32_p
= NULL
;
295 fatent
->bhs
[0] = fatent
->bhs
[1] = NULL
;
296 fatent
->fat_inode
= NULL
;
299 static inline void fatent_set_entry(struct fat_entry
*fatent
, int entry
)
301 fatent
->entry
= entry
;
302 fatent
->u
.ent32_p
= NULL
;
305 static inline void fatent_brelse(struct fat_entry
*fatent
)
308 fatent
->u
.ent32_p
= NULL
;
309 for (i
= 0; i
< fatent
->nr_bhs
; i
++)
310 brelse(fatent
->bhs
[i
]);
312 fatent
->bhs
[0] = fatent
->bhs
[1] = NULL
;
313 fatent
->fat_inode
= NULL
;
316 extern void fat_ent_access_init(struct super_block
*sb
);
317 extern int fat_ent_read(struct inode
*inode
, struct fat_entry
*fatent
,
319 extern int fat_ent_write(struct inode
*inode
, struct fat_entry
*fatent
,
321 extern int fat_alloc_clusters(struct inode
*inode
, int *cluster
,
323 extern int fat_free_clusters(struct inode
*inode
, int cluster
);
324 extern int fat_count_free_clusters(struct super_block
*sb
);
327 extern long fat_generic_ioctl(struct file
*filp
, unsigned int cmd
,
329 extern const struct file_operations fat_file_operations
;
330 extern const struct inode_operations fat_file_inode_operations
;
331 extern int fat_setattr(struct dentry
* dentry
, struct iattr
* attr
);
332 extern void fat_truncate_blocks(struct inode
*inode
, loff_t offset
);
333 extern int fat_getattr(struct vfsmount
*mnt
, struct dentry
*dentry
,
335 extern int fat_file_fsync(struct file
*file
, loff_t start
, loff_t end
,
339 extern void fat_attach(struct inode
*inode
, loff_t i_pos
);
340 extern void fat_detach(struct inode
*inode
);
341 extern struct inode
*fat_iget(struct super_block
*sb
, loff_t i_pos
);
342 extern struct inode
*fat_build_inode(struct super_block
*sb
,
343 struct msdos_dir_entry
*de
, loff_t i_pos
);
344 extern int fat_sync_inode(struct inode
*inode
);
345 extern int fat_fill_super(struct super_block
*sb
, void *data
, int silent
,
346 int isvfat
, void (*setup
)(struct super_block
*));
348 extern int fat_flush_inodes(struct super_block
*sb
, struct inode
*i1
,
350 static inline unsigned long fat_dir_hash(int logstart
)
352 return hash_32(logstart
, FAT_HASH_BITS
);
356 extern __printf(3, 4) __cold
357 void __fat_fs_error(struct super_block
*sb
, int report
, const char *fmt
, ...);
358 #define fat_fs_error(sb, fmt, args...) \
359 __fat_fs_error(sb, 1, fmt , ## args)
360 #define fat_fs_error_ratelimit(sb, fmt, args...) \
361 __fat_fs_error(sb, __ratelimit(&MSDOS_SB(sb)->ratelimit), fmt , ## args)
362 __printf(3, 4) __cold
363 void fat_msg(struct super_block
*sb
, const char *level
, const char *fmt
, ...);
364 #define fat_msg_ratelimit(sb, level, fmt, args...) \
366 if (__ratelimit(&MSDOS_SB(sb)->ratelimit)) \
367 fat_msg(sb, level, fmt, ## args); \
369 extern int fat_clusters_flush(struct super_block
*sb
);
370 extern int fat_chain_add(struct inode
*inode
, int new_dclus
, int nr_cluster
);
371 extern void fat_time_fat2unix(struct msdos_sb_info
*sbi
, struct timespec
*ts
,
372 __le16 __time
, __le16 __date
, u8 time_cs
);
373 extern void fat_time_unix2fat(struct msdos_sb_info
*sbi
, struct timespec
*ts
,
374 __le16
*time
, __le16
*date
, u8
*time_cs
);
375 extern int fat_sync_bhs(struct buffer_head
**bhs
, int nr_bhs
);
377 int fat_cache_init(void);
378 void fat_cache_destroy(void);
382 extern struct dentry
*fat_fh_to_dentry(struct super_block
*sb
, struct fid
*fid
,
383 int fh_len
, int fh_type
);
384 extern struct dentry
*fat_fh_to_parent(struct super_block
*sb
, struct fid
*fid
,
385 int fh_len
, int fh_type
);
386 extern struct dentry
*fat_get_parent(struct dentry
*child_dir
);
388 /* helper for printk */
389 typedef unsigned long long llu
;