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 discard:1; /* Issue discard requests on deletions */ 49 }; 50 51 #define FAT_HASH_BITS 8 52 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) 53 54 /* 55 * MS-DOS file system in-core superblock data 56 */ 57 struct msdos_sb_info { 58 unsigned short sec_per_clus; /* sectors/cluster */ 59 unsigned short cluster_bits; /* log2(cluster_size) */ 60 unsigned int cluster_size; /* cluster size */ 61 unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ 62 unsigned short fat_start; 63 unsigned long fat_length; /* FAT start & length (sec.) */ 64 unsigned long dir_start; 65 unsigned short dir_entries; /* root dir start & entries */ 66 unsigned long data_start; /* first data sector */ 67 unsigned long max_cluster; /* maximum cluster number */ 68 unsigned long root_cluster; /* first cluster of the root directory */ 69 unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ 70 struct mutex fat_lock; 71 unsigned int prev_free; /* previously allocated cluster number */ 72 unsigned int free_clusters; /* -1 if undefined */ 73 unsigned int free_clus_valid; /* is free_clusters valid? */ 74 struct fat_mount_options options; 75 struct nls_table *nls_disk; /* Codepage used on disk */ 76 struct nls_table *nls_io; /* Charset used for input and display */ 77 const void *dir_ops; /* Opaque; default directory operations */ 78 int dir_per_block; /* dir entries per block */ 79 int dir_per_block_bits; /* log2(dir_per_block) */ 80 81 int fatent_shift; 82 struct fatent_operations *fatent_ops; 83 struct inode *fat_inode; 84 85 spinlock_t inode_hash_lock; 86 struct hlist_head inode_hashtable[FAT_HASH_SIZE]; 87 }; 88 89 #define FAT_CACHE_VALID 0 /* special case for valid cache */ 90 91 /* 92 * MS-DOS file system inode data in memory 93 */ 94 struct msdos_inode_info { 95 spinlock_t cache_lru_lock; 96 struct list_head cache_lru; 97 int nr_caches; 98 /* for avoiding the race between fat_free() and fat_get_cluster() */ 99 unsigned int cache_valid_id; 100 101 /* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */ 102 loff_t mmu_private; /* physically allocated size */ 103 104 int i_start; /* first cluster or 0 */ 105 int i_logstart; /* logical first cluster */ 106 int i_attrs; /* unused attribute bits */ 107 loff_t i_pos; /* on-disk position of directory entry or 0 */ 108 struct hlist_node i_fat_hash; /* hash by i_location */ 109 struct inode vfs_inode; 110 }; 111 112 struct fat_slot_info { 113 loff_t i_pos; /* on-disk position of directory entry */ 114 loff_t slot_off; /* offset for slot or de start */ 115 int nr_slots; /* number of slots + 1(de) in filename */ 116 struct msdos_dir_entry *de; 117 struct buffer_head *bh; 118 }; 119 120 static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) 121 { 122 return sb->s_fs_info; 123 } 124 125 static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) 126 { 127 return container_of(inode, struct msdos_inode_info, vfs_inode); 128 } 129 130 /* 131 * If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to 132 * save ATTR_RO instead of ->i_mode. 133 * 134 * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only 135 * bit, it's just used as flag for app. 136 */ 137 static inline int fat_mode_can_hold_ro(struct inode *inode) 138 { 139 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); 140 mode_t mask; 141 142 if (S_ISDIR(inode->i_mode)) { 143 if (!sbi->options.rodir) 144 return 0; 145 mask = ~sbi->options.fs_dmask; 146 } else 147 mask = ~sbi->options.fs_fmask; 148 149 if (!(mask & S_IWUGO)) 150 return 0; 151 return 1; 152 } 153 154 /* Convert attribute bits and a mask to the UNIX mode. */ 155 static inline mode_t fat_make_mode(struct msdos_sb_info *sbi, 156 u8 attrs, mode_t mode) 157 { 158 if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir)) 159 mode &= ~S_IWUGO; 160 161 if (attrs & ATTR_DIR) 162 return (mode & ~sbi->options.fs_dmask) | S_IFDIR; 163 else 164 return (mode & ~sbi->options.fs_fmask) | S_IFREG; 165 } 166 167 /* Return the FAT attribute byte for this inode */ 168 static inline u8 fat_make_attrs(struct inode *inode) 169 { 170 u8 attrs = MSDOS_I(inode)->i_attrs; 171 if (S_ISDIR(inode->i_mode)) 172 attrs |= ATTR_DIR; 173 if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO)) 174 attrs |= ATTR_RO; 175 return attrs; 176 } 177 178 static inline void fat_save_attrs(struct inode *inode, u8 attrs) 179 { 180 if (fat_mode_can_hold_ro(inode)) 181 MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED; 182 else 183 MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO); 184 } 185 186 static inline unsigned char fat_checksum(const __u8 *name) 187 { 188 unsigned char s = name[0]; 189 s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2]; 190 s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4]; 191 s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6]; 192 s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8]; 193 s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10]; 194 return s; 195 } 196 197 static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) 198 { 199 return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus 200 + sbi->data_start; 201 } 202 203 static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) 204 { 205 #ifdef __BIG_ENDIAN 206 while (len--) { 207 *dst++ = src[0] | (src[1] << 8); 208 src += 2; 209 } 210 #else 211 memcpy(dst, src, len * 2); 212 #endif 213 } 214 215 static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) 216 { 217 #ifdef __BIG_ENDIAN 218 while (len--) { 219 dst[0] = *src & 0x00FF; 220 dst[1] = (*src & 0xFF00) >> 8; 221 dst += 2; 222 src++; 223 } 224 #else 225 memcpy(dst, src, len * 2); 226 #endif 227 } 228 229 /* fat/cache.c */ 230 extern void fat_cache_inval_inode(struct inode *inode); 231 extern int fat_get_cluster(struct inode *inode, int cluster, 232 int *fclus, int *dclus); 233 extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, 234 unsigned long *mapped_blocks, int create); 235 236 /* fat/dir.c */ 237 extern const struct file_operations fat_dir_operations; 238 extern int fat_search_long(struct inode *inode, const unsigned char *name, 239 int name_len, struct fat_slot_info *sinfo); 240 extern int fat_dir_empty(struct inode *dir); 241 extern int fat_subdirs(struct inode *dir); 242 extern int fat_scan(struct inode *dir, const unsigned char *name, 243 struct fat_slot_info *sinfo); 244 extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 245 struct msdos_dir_entry **de, loff_t *i_pos); 246 extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); 247 extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 248 struct fat_slot_info *sinfo); 249 extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); 250 251 /* fat/fatent.c */ 252 struct fat_entry { 253 int entry; 254 union { 255 u8 *ent12_p[2]; 256 __le16 *ent16_p; 257 __le32 *ent32_p; 258 } u; 259 int nr_bhs; 260 struct buffer_head *bhs[2]; 261 struct inode *fat_inode; 262 }; 263 264 static inline void fatent_init(struct fat_entry *fatent) 265 { 266 fatent->nr_bhs = 0; 267 fatent->entry = 0; 268 fatent->u.ent32_p = NULL; 269 fatent->bhs[0] = fatent->bhs[1] = NULL; 270 fatent->fat_inode = NULL; 271 } 272 273 static inline void fatent_set_entry(struct fat_entry *fatent, int entry) 274 { 275 fatent->entry = entry; 276 fatent->u.ent32_p = NULL; 277 } 278 279 static inline void fatent_brelse(struct fat_entry *fatent) 280 { 281 int i; 282 fatent->u.ent32_p = NULL; 283 for (i = 0; i < fatent->nr_bhs; i++) 284 brelse(fatent->bhs[i]); 285 fatent->nr_bhs = 0; 286 fatent->bhs[0] = fatent->bhs[1] = NULL; 287 fatent->fat_inode = NULL; 288 } 289 290 extern void fat_ent_access_init(struct super_block *sb); 291 extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, 292 int entry); 293 extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, 294 int new, int wait); 295 extern int fat_alloc_clusters(struct inode *inode, int *cluster, 296 int nr_cluster); 297 extern int fat_free_clusters(struct inode *inode, int cluster); 298 extern int fat_count_free_clusters(struct super_block *sb); 299 300 /* fat/file.c */ 301 extern int fat_generic_ioctl(struct inode *inode, struct file *filp, 302 unsigned int cmd, unsigned long arg); 303 extern const struct file_operations fat_file_operations; 304 extern const struct inode_operations fat_file_inode_operations; 305 extern int fat_setattr(struct dentry * dentry, struct iattr * attr); 306 extern void fat_truncate(struct inode *inode); 307 extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, 308 struct kstat *stat); 309 extern int fat_file_fsync(struct file *file, struct dentry *dentry, 310 int datasync); 311 312 /* fat/inode.c */ 313 extern void fat_attach(struct inode *inode, loff_t i_pos); 314 extern void fat_detach(struct inode *inode); 315 extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); 316 extern struct inode *fat_build_inode(struct super_block *sb, 317 struct msdos_dir_entry *de, loff_t i_pos); 318 extern int fat_sync_inode(struct inode *inode); 319 extern int fat_fill_super(struct super_block *sb, void *data, int silent, 320 const struct inode_operations *fs_dir_inode_ops, int isvfat); 321 322 extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, 323 struct inode *i2); 324 /* fat/misc.c */ 325 extern void fat_fs_error(struct super_block *s, const char *fmt, ...) 326 __attribute__ ((format (printf, 2, 3))) __cold; 327 extern int fat_clusters_flush(struct super_block *sb); 328 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); 329 extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts, 330 __le16 __time, __le16 __date, u8 time_cs); 331 extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts, 332 __le16 *time, __le16 *date, u8 *time_cs); 333 extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); 334 335 int fat_cache_init(void); 336 void fat_cache_destroy(void); 337 338 /* helper for printk */ 339 typedef unsigned long long llu; 340 341 #endif /* !_FAT_H */ 342