1 #ifndef _FAT_H 2 #define _FAT_H 3 4 #include <linux/buffer_head.h> 5 #include <linux/string.h> 6 #include <linux/nls.h> 7 #include <linux/fs.h> 8 #include <linux/mutex.h> 9 #include <linux/msdos_fs.h> 10 11 /* 12 * vfat shortname flags 13 */ 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 */ 19 20 #define FAT_ERRORS_CONT 1 /* ignore error and continue */ 21 #define FAT_ERRORS_PANIC 2 /* panic on error */ 22 #define FAT_ERRORS_RO 3 /* remount r/o on error */ 23 24 struct fat_mount_options { 25 uid_t fs_uid; 26 gid_t fs_gid; 27 unsigned short fs_fmask; 28 unsigned short fs_dmask; 29 unsigned short codepage; /* Codepage for shortname conversions */ 30 char *iocharset; /* Charset used for filename input/display */ 31 unsigned short shortname; /* flags for shortname display/create rule */ 32 unsigned char name_check; /* r = relaxed, n = normal, s = strict */ 33 unsigned char errors; /* On error: continue, panic, remount-ro */ 34 unsigned short allow_utime;/* permission for setting the [am]time */ 35 unsigned quiet:1, /* set = fake successful chmods and chowns */ 36 showexec:1, /* set = only set x bit for com/exe/bat */ 37 sys_immutable:1, /* set = system files are immutable */ 38 dotsOK:1, /* set = hidden and system files are named '.filename' */ 39 isvfat:1, /* 0=no vfat long filename support, 1=vfat support */ 40 utf8:1, /* Use of UTF-8 character set (Default) */ 41 unicode_xlate:1, /* create escape sequences for unhandled Unicode */ 42 numtail:1, /* Does first alias have a numeric '~1' type tail? */ 43 flush:1, /* write things quickly */ 44 nocase:1, /* Does this need case conversion? 0=need case conversion*/ 45 usefree:1, /* Use free_clusters for FAT32 */ 46 tz_utc:1, /* Filesystem timestamps are in UTC */ 47 rodir:1; /* allow ATTR_RO for directory */ 48 }; 49 50 #define FAT_HASH_BITS 8 51 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) 52 53 /* 54 * MS-DOS file system in-core superblock data 55 */ 56 struct msdos_sb_info { 57 unsigned short sec_per_clus; /* sectors/cluster */ 58 unsigned short cluster_bits; /* log2(cluster_size) */ 59 unsigned int cluster_size; /* cluster size */ 60 unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ 61 unsigned short fat_start; 62 unsigned long fat_length; /* FAT start & length (sec.) */ 63 unsigned long dir_start; 64 unsigned short dir_entries; /* root dir start & entries */ 65 unsigned long data_start; /* first data sector */ 66 unsigned long max_cluster; /* maximum cluster number */ 67 unsigned long root_cluster; /* first cluster of the root directory */ 68 unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ 69 struct mutex fat_lock; 70 unsigned int prev_free; /* previously allocated cluster number */ 71 unsigned int free_clusters; /* -1 if undefined */ 72 unsigned int free_clus_valid; /* is free_clusters valid? */ 73 struct fat_mount_options options; 74 struct nls_table *nls_disk; /* Codepage used on disk */ 75 struct nls_table *nls_io; /* Charset used for input and display */ 76 const void *dir_ops; /* Opaque; default directory operations */ 77 int dir_per_block; /* dir entries per block */ 78 int dir_per_block_bits; /* log2(dir_per_block) */ 79 80 int fatent_shift; 81 struct fatent_operations *fatent_ops; 82 struct inode *fat_inode; 83 84 spinlock_t inode_hash_lock; 85 struct hlist_head inode_hashtable[FAT_HASH_SIZE]; 86 }; 87 88 #define FAT_CACHE_VALID 0 /* special case for valid cache */ 89 90 /* 91 * MS-DOS file system inode data in memory 92 */ 93 struct msdos_inode_info { 94 spinlock_t cache_lru_lock; 95 struct list_head cache_lru; 96 int nr_caches; 97 /* for avoiding the race between fat_free() and fat_get_cluster() */ 98 unsigned int cache_valid_id; 99 100 /* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */ 101 loff_t mmu_private; /* physically allocated size */ 102 103 int i_start; /* first cluster or 0 */ 104 int i_logstart; /* logical first cluster */ 105 int i_attrs; /* unused attribute bits */ 106 loff_t i_pos; /* on-disk position of directory entry or 0 */ 107 struct hlist_node i_fat_hash; /* hash by i_location */ 108 struct inode vfs_inode; 109 }; 110 111 struct fat_slot_info { 112 loff_t i_pos; /* on-disk position of directory entry */ 113 loff_t slot_off; /* offset for slot or de start */ 114 int nr_slots; /* number of slots + 1(de) in filename */ 115 struct msdos_dir_entry *de; 116 struct buffer_head *bh; 117 }; 118 119 static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) 120 { 121 return sb->s_fs_info; 122 } 123 124 static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) 125 { 126 return container_of(inode, struct msdos_inode_info, vfs_inode); 127 } 128 129 /* 130 * If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to 131 * save ATTR_RO instead of ->i_mode. 132 * 133 * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only 134 * bit, it's just used as flag for app. 135 */ 136 static inline int fat_mode_can_hold_ro(struct inode *inode) 137 { 138 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); 139 mode_t mask; 140 141 if (S_ISDIR(inode->i_mode)) { 142 if (!sbi->options.rodir) 143 return 0; 144 mask = ~sbi->options.fs_dmask; 145 } else 146 mask = ~sbi->options.fs_fmask; 147 148 if (!(mask & S_IWUGO)) 149 return 0; 150 return 1; 151 } 152 153 /* Convert attribute bits and a mask to the UNIX mode. */ 154 static inline mode_t fat_make_mode(struct msdos_sb_info *sbi, 155 u8 attrs, mode_t mode) 156 { 157 if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir)) 158 mode &= ~S_IWUGO; 159 160 if (attrs & ATTR_DIR) 161 return (mode & ~sbi->options.fs_dmask) | S_IFDIR; 162 else 163 return (mode & ~sbi->options.fs_fmask) | S_IFREG; 164 } 165 166 /* Return the FAT attribute byte for this inode */ 167 static inline u8 fat_make_attrs(struct inode *inode) 168 { 169 u8 attrs = MSDOS_I(inode)->i_attrs; 170 if (S_ISDIR(inode->i_mode)) 171 attrs |= ATTR_DIR; 172 if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO)) 173 attrs |= ATTR_RO; 174 return attrs; 175 } 176 177 static inline void fat_save_attrs(struct inode *inode, u8 attrs) 178 { 179 if (fat_mode_can_hold_ro(inode)) 180 MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED; 181 else 182 MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO); 183 } 184 185 static inline unsigned char fat_checksum(const __u8 *name) 186 { 187 unsigned char s = name[0]; 188 s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2]; 189 s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4]; 190 s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6]; 191 s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8]; 192 s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10]; 193 return s; 194 } 195 196 static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) 197 { 198 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus 199 + sbi->data_start; 200 } 201 202 static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) 203 { 204 #ifdef __BIG_ENDIAN 205 while (len--) { 206 *dst++ = src[0] | (src[1] << 8); 207 src += 2; 208 } 209 #else 210 memcpy(dst, src, len * 2); 211 #endif 212 } 213 214 static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) 215 { 216 #ifdef __BIG_ENDIAN 217 while (len--) { 218 dst[0] = *src & 0x00FF; 219 dst[1] = (*src & 0xFF00) >> 8; 220 dst += 2; 221 src++; 222 } 223 #else 224 memcpy(dst, src, len * 2); 225 #endif 226 } 227 228 /* fat/cache.c */ 229 extern void fat_cache_inval_inode(struct inode *inode); 230 extern int fat_get_cluster(struct inode *inode, int cluster, 231 int *fclus, int *dclus); 232 extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, 233 unsigned long *mapped_blocks, int create); 234 235 /* fat/dir.c */ 236 extern const struct file_operations fat_dir_operations; 237 extern int fat_search_long(struct inode *inode, const unsigned char *name, 238 int name_len, struct fat_slot_info *sinfo); 239 extern int fat_dir_empty(struct inode *dir); 240 extern int fat_subdirs(struct inode *dir); 241 extern int fat_scan(struct inode *dir, const unsigned char *name, 242 struct fat_slot_info *sinfo); 243 extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 244 struct msdos_dir_entry **de, loff_t *i_pos); 245 extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); 246 extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 247 struct fat_slot_info *sinfo); 248 extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); 249 250 /* fat/fatent.c */ 251 struct fat_entry { 252 int entry; 253 union { 254 u8 *ent12_p[2]; 255 __le16 *ent16_p; 256 __le32 *ent32_p; 257 } u; 258 int nr_bhs; 259 struct buffer_head *bhs[2]; 260 struct inode *fat_inode; 261 }; 262 263 static inline void fatent_init(struct fat_entry *fatent) 264 { 265 fatent->nr_bhs = 0; 266 fatent->entry = 0; 267 fatent->u.ent32_p = NULL; 268 fatent->bhs[0] = fatent->bhs[1] = NULL; 269 fatent->fat_inode = NULL; 270 } 271 272 static inline void fatent_set_entry(struct fat_entry *fatent, int entry) 273 { 274 fatent->entry = entry; 275 fatent->u.ent32_p = NULL; 276 } 277 278 static inline void fatent_brelse(struct fat_entry *fatent) 279 { 280 int i; 281 fatent->u.ent32_p = NULL; 282 for (i = 0; i < fatent->nr_bhs; i++) 283 brelse(fatent->bhs[i]); 284 fatent->nr_bhs = 0; 285 fatent->bhs[0] = fatent->bhs[1] = NULL; 286 fatent->fat_inode = NULL; 287 } 288 289 extern void fat_ent_access_init(struct super_block *sb); 290 extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, 291 int entry); 292 extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, 293 int new, int wait); 294 extern int fat_alloc_clusters(struct inode *inode, int *cluster, 295 int nr_cluster); 296 extern int fat_free_clusters(struct inode *inode, int cluster); 297 extern int fat_count_free_clusters(struct super_block *sb); 298 299 /* fat/file.c */ 300 extern int fat_generic_ioctl(struct inode *inode, struct file *filp, 301 unsigned int cmd, unsigned long arg); 302 extern const struct file_operations fat_file_operations; 303 extern const struct inode_operations fat_file_inode_operations; 304 extern int fat_setattr(struct dentry * dentry, struct iattr * attr); 305 extern void fat_truncate(struct inode *inode); 306 extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, 307 struct kstat *stat); 308 extern int fat_file_fsync(struct file *file, struct dentry *dentry, 309 int datasync); 310 311 /* fat/inode.c */ 312 extern void fat_attach(struct inode *inode, loff_t i_pos); 313 extern void fat_detach(struct inode *inode); 314 extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); 315 extern struct inode *fat_build_inode(struct super_block *sb, 316 struct msdos_dir_entry *de, loff_t i_pos); 317 extern int fat_sync_inode(struct inode *inode); 318 extern int fat_fill_super(struct super_block *sb, void *data, int silent, 319 const struct inode_operations *fs_dir_inode_ops, int isvfat); 320 321 extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, 322 struct inode *i2); 323 /* fat/misc.c */ 324 extern void fat_fs_error(struct super_block *s, const char *fmt, ...) 325 __attribute__ ((format (printf, 2, 3))) __cold; 326 extern int fat_clusters_flush(struct super_block *sb); 327 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); 328 extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts, 329 __le16 __time, __le16 __date, u8 time_cs); 330 extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts, 331 __le16 *time, __le16 *date, u8 *time_cs); 332 extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); 333 334 int fat_cache_init(void); 335 void fat_cache_destroy(void); 336 337 /* helper for printk */ 338 typedef unsigned long long llu; 339 340 #endif /* !_FAT_H */ 341