1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * R/O (V)FAT 12/16/32 filesystem implementation by Marcus Sundberg
4 *
5 * 2002-07-28 - rjones@nexus-tech.net - ported to ppcboot v1.1.6
6 * 2003-03-10 - kharris@nexus-tech.net - ported to u-boot
7 */
8
9 #ifndef _FAT_H_
10 #define _FAT_H_
11
12 #include <fs.h>
13 #include <asm/byteorder.h>
14
15 struct disk_partition;
16
17 /* Maximum Long File Name length supported here is 128 UTF-16 code units */
18 #define VFAT_MAXLEN_BYTES 256 /* Maximum LFN buffer in bytes */
19 #define VFAT_MAXSEQ 9 /* Up to 9 of 13 2-byte UTF-16 entries */
20 #define PREFETCH_BLOCKS 2
21
22 #define MAX_CLUSTSIZE CONFIG_FS_FAT_MAX_CLUSTSIZE
23
24 #define DIRENTSPERCLUST ((mydata->clust_size * mydata->sect_size) / \
25 sizeof(dir_entry))
26
27 #define FATBUFBLOCKS 6
28 #define FATBUFSIZE (mydata->sect_size * FATBUFBLOCKS)
29 #define FAT12BUFSIZE ((FATBUFSIZE*2)/3)
30 #define FAT16BUFSIZE (FATBUFSIZE/2)
31 #define FAT32BUFSIZE (FATBUFSIZE/4)
32
33 /* Maximum number of entry for long file name according to spec */
34 #define MAX_LFN_SLOT 20
35
36 /* File attributes */
37 #define ATTR_RO 1
38 #define ATTR_HIDDEN 2
39 #define ATTR_SYS 4
40 #define ATTR_VOLUME 8
41 #define ATTR_DIR 16
42 #define ATTR_ARCH 32
43
44 #define ATTR_VFAT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME)
45
46 #define DELETED_FLAG ((char)0xe5) /* Marks deleted files when in name[0] */
47 #define aRING 0x05 /* Used as special character in name[0] */
48
49 /*
50 * Indicates that the entry is the last long entry in a set of long
51 * dir entries
52 */
53 #define LAST_LONG_ENTRY_MASK 0x40
54
55 #define ISDIRDELIM(c) ((c) == '/' || (c) == '\\')
56
57 #define FSTYPE_NONE (-1)
58
59 #if defined(__linux__) && defined(__KERNEL__)
60 #define FAT2CPU16 le16_to_cpu
61 #define FAT2CPU32 le32_to_cpu
62 #else
63 #if __LITTLE_ENDIAN
64 #define FAT2CPU16(x) (x)
65 #define FAT2CPU32(x) (x)
66 #else
67 #define FAT2CPU16(x) ((((x) & 0x00ff) << 8) | (((x) & 0xff00) >> 8))
68 #define FAT2CPU32(x) ((((x) & 0x000000ff) << 24) | \
69 (((x) & 0x0000ff00) << 8) | \
70 (((x) & 0x00ff0000) >> 8) | \
71 (((x) & 0xff000000) >> 24))
72 #endif
73 #endif
74
75 #define START(dent) (FAT2CPU16((dent)->start) \
76 + (mydata->fatsize != 32 ? 0 : \
77 (FAT2CPU16((dent)->starthi) << 16)))
78 #define IS_LAST_CLUST(x, fatsize) ((x) >= ((fatsize) != 32 ? \
79 ((fatsize) != 16 ? 0xff8 : 0xfff8) : \
80 0xffffff8))
81 #define CHECK_CLUST(x, fatsize) ((x) <= 1 || \
82 (x) >= ((fatsize) != 32 ? \
83 ((fatsize) != 16 ? 0xff0 : 0xfff0) : \
84 0xffffff0))
85
86 typedef struct boot_sector {
87 __u8 ignored[3]; /* Bootstrap code */
88 char system_id[8]; /* Name of fs */
89 __u8 sector_size[2]; /* Bytes/sector */
90 __u8 cluster_size; /* Sectors/cluster */
91 __u16 reserved; /* Number of reserved sectors */
92 __u8 fats; /* Number of FATs */
93 __u8 dir_entries[2]; /* Number of root directory entries */
94 __u8 sectors[2]; /* Number of sectors */
95 __u8 media; /* Media code */
96 __u16 fat_length; /* Sectors/FAT */
97 __u16 secs_track; /* Sectors/track */
98 __u16 heads; /* Number of heads */
99 __u32 hidden; /* Number of hidden sectors */
100 __u32 total_sect; /* Number of sectors (if sectors == 0) */
101
102 /* FAT32 only */
103 __u32 fat32_length; /* Sectors/FAT */
104 __u16 flags; /* Bit 8: fat mirroring, low 4: active fat */
105 __u8 version[2]; /* Filesystem version */
106 __u32 root_cluster; /* First cluster in root directory */
107 __u16 info_sector; /* Filesystem info sector */
108 __u16 backup_boot; /* Backup boot sector */
109 __u16 reserved2[6]; /* Unused */
110 } boot_sector;
111
112 typedef struct volume_info
113 {
114 __u8 drive_number; /* BIOS drive number */
115 __u8 reserved; /* Unused */
116 __u8 ext_boot_sign; /* 0x29 if fields below exist (DOS 3.3+) */
117 __u8 volume_id[4]; /* Volume ID number */
118 char volume_label[11]; /* Volume label */
119 char fs_type[8]; /* Typically FAT12, FAT16, or FAT32 */
120 /* Boot code comes next, all but 2 bytes to fill up sector */
121 /* Boot sign comes last, 2 bytes */
122 } volume_info;
123
124 /* see dir_entry::lcase: */
125 #define CASE_LOWER_BASE 8 /* base (name) is lower case */
126 #define CASE_LOWER_EXT 16 /* extension is lower case */
127
128 struct nameext {
129 char name[8];
130 char ext[3];
131 };
132
133 typedef struct dir_entry {
134 struct nameext nameext; /* Name and extension */
135 __u8 attr; /* Attribute bits */
136 __u8 lcase; /* Case for name and ext (CASE_LOWER_x) */
137 __u8 ctime_ms; /* Creation time, milliseconds */
138 __u16 ctime; /* Creation time */
139 __u16 cdate; /* Creation date */
140 __u16 adate; /* Last access date */
141 __u16 starthi; /* High 16 bits of cluster in FAT32 */
142 __u16 time,date,start;/* Time, date and first cluster */
143 __u32 size; /* File size in bytes */
144 } dir_entry;
145
146 typedef struct dir_slot {
147 __u8 id; /* Sequence number for slot */
148 __u8 name0_4[10]; /* First 5 characters in name */
149 __u8 attr; /* Attribute byte */
150 __u8 reserved; /* Unused */
151 __u8 alias_checksum;/* Checksum for 8.3 alias */
152 __u8 name5_10[12]; /* 6 more characters in name */
153 __u16 start; /* Unused */
154 __u8 name11_12[4]; /* Last 2 characters in name */
155 } dir_slot;
156
157 /*
158 * Private filesystem parameters
159 *
160 * Note: FAT buffer has to be 32 bit aligned
161 * (see FAT32 accesses)
162 */
163 typedef struct {
164 __u8 *fatbuf; /* Current FAT buffer */
165 int fatsize; /* Size of FAT in bits */
166 __u32 fatlength; /* Length of FAT in sectors */
167 __u16 fat_sect; /* Starting sector of the FAT */
168 __u8 fat_dirty; /* Set if fatbuf has been modified */
169 __u32 rootdir_sect; /* Start sector of root directory */
170 __u16 sect_size; /* Size of sectors in bytes */
171 __u16 clust_size; /* Size of clusters in sectors */
172 int data_begin; /* The sector of the first cluster, can be negative */
173 int fatbufnum; /* Used by get_fatent, init to -1 */
174 int rootdir_size; /* Size of root dir for non-FAT32 */
175 __u32 root_cluster; /* First cluster of root dir for FAT32 */
176 u32 total_sect; /* Number of sectors */
177 int fats; /* Number of FATs */
178 } fsdata;
179
180 struct fat_itr;
181 typedef struct fat_itr fat_itr;
182
clust_to_sect(fsdata * fsdata,u32 clust)183 static inline u32 clust_to_sect(fsdata *fsdata, u32 clust)
184 {
185 return fsdata->data_begin + clust * fsdata->clust_size;
186 }
187
sect_to_clust(fsdata * fsdata,int sect)188 static inline u32 sect_to_clust(fsdata *fsdata, int sect)
189 {
190 return (sect - fsdata->data_begin) / fsdata->clust_size;
191 }
192
193 int file_fat_detectfs(void);
194 int fat_exists(const char *filename);
195 int fat_size(const char *filename, loff_t *size);
196 int file_fat_read(const char *filename, void *buffer, int maxsize);
197 int fat_set_blk_dev(struct blk_desc *rbdd, struct disk_partition *info);
198 int fat_register_device(struct blk_desc *dev_desc, int part_no);
199
200 int file_fat_write(const char *filename, void *buf, loff_t offset, loff_t len,
201 loff_t *actwrite);
202 int fat_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
203 loff_t *actread);
204 int fat_opendir(const char *filename, struct fs_dir_stream **dirsp);
205 int fat_readdir(struct fs_dir_stream *dirs, struct fs_dirent **dentp);
206 void fat_closedir(struct fs_dir_stream *dirs);
207 int fat_unlink(const char *filename);
208 int fat_rename(const char *old_path, const char *new_path);
209 int fat_mkdir(const char *dirname);
210 void fat_close(void);
211 void *fat_next_cluster(fat_itr *itr, unsigned int *nbytes);
212
213 /**
214 * fat_uuid() - get FAT volume ID
215 *
216 * The FAT volume ID returned in @uuid_str as hexadecimal number in XXXX-XXXX
217 * format.
218 *
219 * @uuid_str: caller allocated buffer of at least 10 bytes for the volume ID
220 * Return: 0 on success
221 */
222 int fat_uuid(char *uuid_str);
223
224 #endif /* _FAT_H_ */
225