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 <asm/byteorder.h> 13 #include <fs.h> 14 15 /* Maximum Long File Name length supported here is 128 UTF-16 code units */ 16 #define VFAT_MAXLEN_BYTES 256 /* Maximum LFN buffer in bytes */ 17 #define VFAT_MAXSEQ 9 /* Up to 9 of 13 2-byte UTF-16 entries */ 18 #define PREFETCH_BLOCKS 2 19 20 #define MAX_CLUSTSIZE CONFIG_FS_FAT_MAX_CLUSTSIZE 21 22 #define DIRENTSPERBLOCK (mydata->sect_size / sizeof(dir_entry)) 23 #define DIRENTSPERCLUST ((mydata->clust_size * mydata->sect_size) / \ 24 sizeof(dir_entry)) 25 26 #define FATBUFBLOCKS 6 27 #define FATBUFSIZE (mydata->sect_size * FATBUFBLOCKS) 28 #define FAT12BUFSIZE ((FATBUFSIZE*2)/3) 29 #define FAT16BUFSIZE (FATBUFSIZE/2) 30 #define FAT32BUFSIZE (FATBUFSIZE/4) 31 32 /* Maximum number of entry for long file name according to spec */ 33 #define MAX_LFN_SLOT 20 34 35 /* Filesystem identifiers */ 36 #define FAT12_SIGN "FAT12 " 37 #define FAT16_SIGN "FAT16 " 38 #define FAT32_SIGN "FAT32 " 39 #define SIGNLEN 8 40 41 /* File attributes */ 42 #define ATTR_RO 1 43 #define ATTR_HIDDEN 2 44 #define ATTR_SYS 4 45 #define ATTR_VOLUME 8 46 #define ATTR_DIR 16 47 #define ATTR_ARCH 32 48 49 #define ATTR_VFAT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME) 50 51 #define DELETED_FLAG ((char)0xe5) /* Marks deleted files when in name[0] */ 52 #define aRING 0x05 /* Used as special character in name[0] */ 53 54 /* 55 * Indicates that the entry is the last long entry in a set of long 56 * dir entries 57 */ 58 #define LAST_LONG_ENTRY_MASK 0x40 59 60 #define ISDIRDELIM(c) ((c) == '/' || (c) == '\\') 61 62 #define FSTYPE_NONE (-1) 63 64 #if defined(__linux__) && defined(__KERNEL__) 65 #define FAT2CPU16 le16_to_cpu 66 #define FAT2CPU32 le32_to_cpu 67 #else 68 #if __LITTLE_ENDIAN 69 #define FAT2CPU16(x) (x) 70 #define FAT2CPU32(x) (x) 71 #else 72 #define FAT2CPU16(x) ((((x) & 0x00ff) << 8) | (((x) & 0xff00) >> 8)) 73 #define FAT2CPU32(x) ((((x) & 0x000000ff) << 24) | \ 74 (((x) & 0x0000ff00) << 8) | \ 75 (((x) & 0x00ff0000) >> 8) | \ 76 (((x) & 0xff000000) >> 24)) 77 #endif 78 #endif 79 80 #define START(dent) (FAT2CPU16((dent)->start) \ 81 + (mydata->fatsize != 32 ? 0 : \ 82 (FAT2CPU16((dent)->starthi) << 16))) 83 #define IS_LAST_CLUST(x, fatsize) ((x) >= ((fatsize) != 32 ? \ 84 ((fatsize) != 16 ? 0xff8 : 0xfff8) : \ 85 0xffffff8)) 86 #define CHECK_CLUST(x, fatsize) ((x) <= 1 || \ 87 (x) >= ((fatsize) != 32 ? \ 88 ((fatsize) != 16 ? 0xff0 : 0xfff0) : \ 89 0xffffff0)) 90 91 typedef struct boot_sector { 92 __u8 ignored[3]; /* Bootstrap code */ 93 char system_id[8]; /* Name of fs */ 94 __u8 sector_size[2]; /* Bytes/sector */ 95 __u8 cluster_size; /* Sectors/cluster */ 96 __u16 reserved; /* Number of reserved sectors */ 97 __u8 fats; /* Number of FATs */ 98 __u8 dir_entries[2]; /* Number of root directory entries */ 99 __u8 sectors[2]; /* Number of sectors */ 100 __u8 media; /* Media code */ 101 __u16 fat_length; /* Sectors/FAT */ 102 __u16 secs_track; /* Sectors/track */ 103 __u16 heads; /* Number of heads */ 104 __u32 hidden; /* Number of hidden sectors */ 105 __u32 total_sect; /* Number of sectors (if sectors == 0) */ 106 107 /* FAT32 only */ 108 __u32 fat32_length; /* Sectors/FAT */ 109 __u16 flags; /* Bit 8: fat mirroring, low 4: active fat */ 110 __u8 version[2]; /* Filesystem version */ 111 __u32 root_cluster; /* First cluster in root directory */ 112 __u16 info_sector; /* Filesystem info sector */ 113 __u16 backup_boot; /* Backup boot sector */ 114 __u16 reserved2[6]; /* Unused */ 115 } boot_sector; 116 117 typedef struct volume_info 118 { 119 __u8 drive_number; /* BIOS drive number */ 120 __u8 reserved; /* Unused */ 121 __u8 ext_boot_sign; /* 0x29 if fields below exist (DOS 3.3+) */ 122 __u8 volume_id[4]; /* Volume ID number */ 123 char volume_label[11]; /* Volume label */ 124 char fs_type[8]; /* Typically FAT12, FAT16, or FAT32 */ 125 /* Boot code comes next, all but 2 bytes to fill up sector */ 126 /* Boot sign comes last, 2 bytes */ 127 } volume_info; 128 129 /* see dir_entry::lcase: */ 130 #define CASE_LOWER_BASE 8 /* base (name) is lower case */ 131 #define CASE_LOWER_EXT 16 /* extension is lower case */ 132 133 typedef struct dir_entry { 134 char name[8],ext[3]; /* 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 static inline u32 clust_to_sect(fsdata *fsdata, u32 clust) 181 { 182 return fsdata->data_begin + clust * fsdata->clust_size; 183 } 184 185 static inline u32 sect_to_clust(fsdata *fsdata, int sect) 186 { 187 return (sect - fsdata->data_begin) / fsdata->clust_size; 188 } 189 190 int file_fat_detectfs(void); 191 int fat_exists(const char *filename); 192 int fat_size(const char *filename, loff_t *size); 193 int file_fat_read_at(const char *filename, loff_t pos, void *buffer, 194 loff_t maxsize, loff_t *actread); 195 int file_fat_read(const char *filename, void *buffer, int maxsize); 196 int fat_set_blk_dev(struct blk_desc *rbdd, disk_partition_t *info); 197 int fat_register_device(struct blk_desc *dev_desc, int part_no); 198 199 int file_fat_write(const char *filename, void *buf, loff_t offset, loff_t len, 200 loff_t *actwrite); 201 int fat_read_file(const char *filename, void *buf, loff_t offset, loff_t len, 202 loff_t *actread); 203 int fat_opendir(const char *filename, struct fs_dir_stream **dirsp); 204 int fat_readdir(struct fs_dir_stream *dirs, struct fs_dirent **dentp); 205 void fat_closedir(struct fs_dir_stream *dirs); 206 int fat_unlink(const char *filename); 207 int fat_mkdir(const char *dirname); 208 void fat_close(void); 209 #endif /* _FAT_H_ */ 210