4 #include <linux/buffer_head.h>
5 #include <linux/string.h>
8 #include <linux/mutex.h>
9 #include <linux/msdos_fs.h>
12 * vfat shortname flags
14 #define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */
15 #define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */
16 #define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */
17 #define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */
18 #define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */
20 struct fat_mount_options {
23 unsigned short fs_fmask;
24 unsigned short fs_dmask;
25 unsigned short codepage; /* Codepage for shortname conversions */
26 char *iocharset; /* Charset used for filename input/display */
27 unsigned short shortname; /* flags for shortname display/create rule */
28 unsigned char name_check; /* r = relaxed, n = normal, s = strict */
29 unsigned short allow_utime;/* permission for setting the [am]time */
30 unsigned quiet:1, /* set = fake successful chmods and chowns */
31 showexec:1, /* set = only set x bit for com/exe/bat */
32 sys_immutable:1, /* set = system files are immutable */
33 dotsOK:1, /* set = hidden and system files are named '.filename' */
34 isvfat:1, /* 0=no vfat long filename support, 1=vfat support */
35 utf8:1, /* Use of UTF-8 character set (Default) */
36 unicode_xlate:1, /* create escape sequences for unhandled Unicode */
37 numtail:1, /* Does first alias have a numeric '~1' type tail? */
38 flush:1, /* write things quickly */
39 nocase:1, /* Does this need case conversion? 0=need case conversion*/
40 usefree:1, /* Use free_clusters for FAT32 */
41 tz_utc:1; /* Filesystem timestamps are in UTC */
44 #define FAT_HASH_BITS 8
45 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS)
46 #define FAT_HASH_MASK (FAT_HASH_SIZE-1)
49 * MS-DOS file system in-core superblock data
51 struct msdos_sb_info {
52 unsigned short sec_per_clus; /* sectors/cluster */
53 unsigned short cluster_bits; /* log2(cluster_size) */
54 unsigned int cluster_size; /* cluster size */
55 unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */
56 unsigned short fat_start;
57 unsigned long fat_length; /* FAT start & length (sec.) */
58 unsigned long dir_start;
59 unsigned short dir_entries; /* root dir start & entries */
60 unsigned long data_start; /* first data sector */
61 unsigned long max_cluster; /* maximum cluster number */
62 unsigned long root_cluster; /* first cluster of the root directory */
63 unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */
64 struct mutex fat_lock;
65 unsigned int prev_free; /* previously allocated cluster number */
66 unsigned int free_clusters; /* -1 if undefined */
67 unsigned int free_clus_valid; /* is free_clusters valid? */
68 struct fat_mount_options options;
69 struct nls_table *nls_disk; /* Codepage used on disk */
70 struct nls_table *nls_io; /* Charset used for input and display */
71 const void *dir_ops; /* Opaque; default directory operations */
72 int dir_per_block; /* dir entries per block */
73 int dir_per_block_bits; /* log2(dir_per_block) */
76 struct fatent_operations *fatent_ops;
78 spinlock_t inode_hash_lock;
79 struct hlist_head inode_hashtable[FAT_HASH_SIZE];
82 #define FAT_CACHE_VALID 0 /* special case for valid cache */
85 * MS-DOS file system inode data in memory
87 struct msdos_inode_info {
88 spinlock_t cache_lru_lock;
89 struct list_head cache_lru;
91 /* for avoiding the race between fat_free() and fat_get_cluster() */
92 unsigned int cache_valid_id;
95 int i_start; /* first cluster or 0 */
96 int i_logstart; /* logical first cluster */
97 int i_attrs; /* unused attribute bits */
98 loff_t i_pos; /* on-disk position of directory entry or 0 */
99 struct hlist_node i_fat_hash; /* hash by i_location */
100 struct inode vfs_inode;
103 struct fat_slot_info {
104 loff_t i_pos; /* on-disk position of directory entry */
105 loff_t slot_off; /* offset for slot or de start */
106 int nr_slots; /* number of slots + 1(de) in filename */
107 struct msdos_dir_entry *de;
108 struct buffer_head *bh;
111 static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb)
113 return sb->s_fs_info;
116 static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
118 return container_of(inode, struct msdos_inode_info, vfs_inode);
121 /* Return the FAT attribute byte for this inode */
122 static inline u8 fat_attr(struct inode *inode)
124 return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) |
125 (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) |
126 MSDOS_I(inode)->i_attrs;
129 static inline unsigned char fat_checksum(const __u8 *name)
131 unsigned char s = name[0];
132 s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2];
133 s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4];
134 s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6];
135 s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8];
136 s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10];
140 static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus)
142 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus
146 static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len)
150 *dst++ = src[0] | (src[1] << 8);
154 memcpy(dst, src, len * 2);
158 static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len)
162 dst[0] = *src & 0x00FF;
163 dst[1] = (*src & 0xFF00) >> 8;
168 memcpy(dst, src, len * 2);
173 extern void fat_cache_inval_inode(struct inode *inode);
174 extern int fat_get_cluster(struct inode *inode, int cluster,
175 int *fclus, int *dclus);
176 extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
177 unsigned long *mapped_blocks);
180 extern const struct file_operations fat_dir_operations;
181 extern int fat_search_long(struct inode *inode, const unsigned char *name,
182 int name_len, struct fat_slot_info *sinfo);
183 extern int fat_dir_empty(struct inode *dir);
184 extern int fat_subdirs(struct inode *dir);
185 extern int fat_scan(struct inode *dir, const unsigned char *name,
186 struct fat_slot_info *sinfo);
187 extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
188 struct msdos_dir_entry **de, loff_t *i_pos);
189 extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts);
190 extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
191 struct fat_slot_info *sinfo);
192 extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo);
203 struct buffer_head *bhs[2];
206 static inline void fatent_init(struct fat_entry *fatent)
210 fatent->u.ent32_p = NULL;
211 fatent->bhs[0] = fatent->bhs[1] = NULL;
214 static inline void fatent_set_entry(struct fat_entry *fatent, int entry)
216 fatent->entry = entry;
217 fatent->u.ent32_p = NULL;
220 static inline void fatent_brelse(struct fat_entry *fatent)
223 fatent->u.ent32_p = NULL;
224 for (i = 0; i < fatent->nr_bhs; i++)
225 brelse(fatent->bhs[i]);
227 fatent->bhs[0] = fatent->bhs[1] = NULL;
230 extern void fat_ent_access_init(struct super_block *sb);
231 extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent,
233 extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent,
235 extern int fat_alloc_clusters(struct inode *inode, int *cluster,
237 extern int fat_free_clusters(struct inode *inode, int cluster);
238 extern int fat_count_free_clusters(struct super_block *sb);
241 extern int fat_generic_ioctl(struct inode *inode, struct file *filp,
242 unsigned int cmd, unsigned long arg);
243 extern const struct file_operations fat_file_operations;
244 extern const struct inode_operations fat_file_inode_operations;
245 extern int fat_setattr(struct dentry * dentry, struct iattr * attr);
246 extern void fat_truncate(struct inode *inode);
247 extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry,
251 extern void fat_attach(struct inode *inode, loff_t i_pos);
252 extern void fat_detach(struct inode *inode);
253 extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos);
254 extern struct inode *fat_build_inode(struct super_block *sb,
255 struct msdos_dir_entry *de, loff_t i_pos);
256 extern int fat_sync_inode(struct inode *inode);
257 extern int fat_fill_super(struct super_block *sb, void *data, int silent,
258 const struct inode_operations *fs_dir_inode_ops, int isvfat);
260 extern int fat_flush_inodes(struct super_block *sb, struct inode *i1,
263 extern void fat_fs_panic(struct super_block *s, const char *fmt, ...);
264 extern void fat_clusters_flush(struct super_block *sb);
265 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
266 extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
267 __le16 __time, __le16 __date, u8 time_cs);
268 extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
269 __le16 *time, __le16 *date, u8 *time_cs);
270 extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs);
272 int fat_cache_init(void);
273 void fat_cache_destroy(void);