Line data Source code
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 2 :
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 1 :
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 1 :
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 1438 : return sb->s_fs_info;
123 : }
124 :
125 : static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
126 : {
127 14001 : 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 88 : struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
140 22 : mode_t mask;
141 22 :
142 66 : if (S_ISDIR(inode->i_mode)) {
143 44 : if (!sbi->options.rodir)
144 22 : return 0;
145 22 : mask = ~sbi->options.fs_dmask;
146 : } else
147 22 : mask = ~sbi->options.fs_fmask;
148 :
149 44 : if (!(mask & S_IWUGO))
150 22 : return 0;
151 22 : 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 42 : if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir))
159 7 : mode &= ~S_IWUGO;
160 :
161 14 : if (attrs & ATTR_DIR)
162 7 : return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
163 : else
164 7 : 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 45 : u8 attrs = MSDOS_I(inode)->i_attrs;
171 36 : if (S_ISDIR(inode->i_mode))
172 18 : attrs |= ATTR_DIR;
173 63 : if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO))
174 9 : attrs |= ATTR_RO;
175 9 : return attrs;
176 : }
177 :
178 : static inline void fat_save_attrs(struct inode *inode, u8 attrs)
179 : {
180 20 : if (fat_mode_can_hold_ro(inode))
181 16 : MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED;
182 4 : else
183 12 : MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO);
184 8 : }
185 :
186 : static inline unsigned char fat_checksum(const __u8 *name)
187 : {
188 6 : unsigned char s = name[0];
189 6 : s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2];
190 6 : s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4];
191 6 : s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6];
192 6 : s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8];
193 6 : s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10];
194 3 : return s;
195 : }
196 :
197 : static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus)
198 : {
199 72 : 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 9 : memcpy(dst, src, len * 2);
212 9 : #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 1 : 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 2 :
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 : {
266 310 : fatent->nr_bhs = 0;
267 155 : fatent->entry = 0;
268 155 : fatent->u.ent32_p = NULL;
269 465 : fatent->bhs[0] = fatent->bhs[1] = NULL;
270 155 : fatent->fat_inode = NULL;
271 155 : }
272 :
273 : static inline void fatent_set_entry(struct fat_entry *fatent, int entry)
274 : {
275 82 : fatent->entry = entry;
276 82 : fatent->u.ent32_p = NULL;
277 82 : }
278 :
279 : static inline void fatent_brelse(struct fat_entry *fatent)
280 : {
281 570 : int i;
282 1140 : fatent->u.ent32_p = NULL;
283 2850 : for (i = 0; i < fatent->nr_bhs; i++)
284 1710 : brelse(fatent->bhs[i]);
285 1710 : fatent->nr_bhs = 0;
286 1710 : fatent->bhs[0] = fatent->bhs[1] = NULL;
287 570 : fatent->fat_inode = NULL;
288 570 : }
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 1 : extern const struct file_operations fat_file_operations;
304 1 : 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 2 :
341 : #endif /* !_FAT_H */
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