[530] | 1 | //////////////////////////////////////////////////////////////////////////////// |
---|
[258] | 2 | // File : fat32.h |
---|
| 3 | // Date : 01/09/2013 |
---|
[587] | 4 | // Author : Alain Greiner / Marco Jankovic |
---|
[258] | 5 | // Copyright (c) UPMC-LIP6 |
---|
[530] | 6 | //////////////////////////////////////////////////////////////////////////////// |
---|
[258] | 7 | |
---|
| 8 | #ifndef _FAT32_H |
---|
| 9 | #define _FAT32_H |
---|
| 10 | |
---|
[663] | 11 | #include "fat32_shared.h" |
---|
[258] | 12 | #include "giet_config.h" |
---|
[503] | 13 | #include "kernel_locks.h" |
---|
[258] | 14 | |
---|
[530] | 15 | /*************** Partition Boot Sector Format **********************************/ |
---|
[258] | 16 | // offset | length |
---|
| 17 | #define BS_JMPBOOT 0 , 3 |
---|
| 18 | #define BS_OEMNAME 3 , 8 |
---|
| 19 | #define BPB_BYTSPERSEC 11 , 2 |
---|
| 20 | #define BPB_SECPERCLUS 13 , 1 |
---|
| 21 | #define BPB_RSVDSECCNT 14 , 2 |
---|
| 22 | #define BPB_NUMFATS 16 , 1 |
---|
| 23 | #define BPB_ROOTENTCNT 17 , 2 |
---|
| 24 | #define BPB_TOTSEC16 19 , 2 |
---|
| 25 | #define BPB_MEDIA 21 , 1 |
---|
| 26 | #define BPB_FATSZ16 22 , 2 |
---|
| 27 | #define BPB_SECPERTRK 24 , 2 |
---|
| 28 | #define BPB_NUMHEADS 26 , 2 |
---|
| 29 | #define BPB_HIDDSEC 28 , 4 |
---|
| 30 | #define BPB_TOTSEC32 32 , 4 |
---|
| 31 | #define BPB_PARTITION_TABLE 446 , 64 |
---|
| 32 | |
---|
| 33 | // FAT 32 |
---|
| 34 | #define BPB_FAT32_FATSZ32 36 , 4 |
---|
| 35 | #define BPB_FAT32_EXTFLAGS 40 , 2 |
---|
| 36 | #define BPB_FAT32_FSVER 42 , 2 |
---|
| 37 | #define BPB_FAT32_ROOTCLUS 44 , 4 |
---|
| 38 | #define BPB_FAT32_FSINFO 48 , 2 |
---|
| 39 | #define BPB_FAT32_BKBOOTSEC 50 , 2 |
---|
| 40 | #define BS_FAT32_DRVNUM 64 , 1 |
---|
| 41 | #define BS_FAT32_BOOTSIG 66 , 1 |
---|
| 42 | #define BS_FAT32_VOLID 67 , 4 |
---|
| 43 | #define BS_FAT32_VOLLAB 71 , 11 |
---|
| 44 | #define BS_FAT32_FILSYSTYPE 82 , 8 |
---|
| 45 | |
---|
| 46 | // Partitions |
---|
| 47 | #define FIRST_PARTITION_ACTIVE 446 , 8 |
---|
| 48 | #define FIRST_PARTITION_BEGIN_LBA 454 , 4 |
---|
| 49 | #define FIRST_PARTITION_SIZE 458 , 4 |
---|
| 50 | #define SECOND_PARTITION_ACTIVE 462 , 8 |
---|
| 51 | #define SECOND_PARTITION_BEGIN_LBA 470 , 4 |
---|
| 52 | #define SECOND_PARTITION_SIZE 474 , 4 |
---|
| 53 | #define THIRD_PARTITION_ACTIVE 478 , 8 |
---|
| 54 | #define THIRD_PARTITION_BEGIN_LBA 486 , 4 |
---|
| 55 | #define THIRD_PARTITION_SIZE 490 , 4 |
---|
| 56 | #define FOURTH_PARTITION_ACTIVE 494 , 8 |
---|
| 57 | #define FOURTH_PARTITION_BEGIN_LBA 502 , 4 |
---|
| 58 | #define FOURTH_PARTITION_SIZE 506 , 4 |
---|
[530] | 59 | /*******************************************************************************/ |
---|
[258] | 60 | |
---|
| 61 | #define MBR_SIGNATURE_POSITION 510 , 2 |
---|
| 62 | #define MBR_SIGNATURE_VALUE 0xAA55 |
---|
| 63 | |
---|
[530] | 64 | /************** FAT_FS_INFO SECTOR ********************************************/ |
---|
[258] | 65 | #define FS_SIGNATURE_VALUE_1 0x52526141 |
---|
| 66 | #define FS_SIGNATURE_VALUE_2 0x72724161 |
---|
| 67 | #define FS_SIGNATURE_VALUE_3 0x000055AA |
---|
| 68 | #define FS_SIGNATURE_POSITION_1 0 , 4 |
---|
| 69 | #define FS_SIGNATURE_POSITION_2 484 , 4 |
---|
| 70 | #define FS_SIGNATURE_POSITION_3 508 , 4 |
---|
[587] | 71 | #define FS_FREE_CLUSTERS 488 , 4 |
---|
[291] | 72 | #define FS_FREE_CLUSTER_HINT 492 , 4 |
---|
[530] | 73 | /*******************************************************************************/ |
---|
[258] | 74 | |
---|
| 75 | #define DIR_ENTRY_SIZE 32 |
---|
| 76 | |
---|
[587] | 77 | #define NAME_MAX_SIZE 31 |
---|
| 78 | |
---|
[530] | 79 | /******* Directory Entry Structure (32 bytes) **********************************/ |
---|
[587] | 80 | // offset | length |
---|
| 81 | #define DIR_NAME 0 , 11 // dir_entry name |
---|
| 82 | #define DIR_ATTR 11 , 1 // attributes |
---|
| 83 | #define DIR_NTRES 12 , 1 // reserved for the OS |
---|
| 84 | #define DIR_CRT_TIMES_TENTH 13 , 1 |
---|
| 85 | #define DIR_FST_CLUS_HI 20 , 2 // cluster index 16 MSB bits |
---|
| 86 | #define DIR_WRT_TIME 22 , 2 // time of last write |
---|
| 87 | #define DIR_WRT_DATE 24 , 2 // date of last write |
---|
| 88 | #define DIR_FST_CLUS_LO 26 , 2 // cluster index 16 LSB bit |
---|
| 89 | #define DIR_FILE_SIZE 28 , 4 // file size (up to 4 giga bytes) |
---|
[530] | 90 | /*******************************************************************************/ |
---|
[258] | 91 | |
---|
[530] | 92 | /******* LFN Directory Entry Structure (32 bytes) *****************************/ |
---|
[587] | 93 | // offset | length |
---|
| 94 | #define LDIR_ORD 0 , 1 // Sequence number (from 0x01 to 0x0f) |
---|
| 95 | #define LDIR_NAME_1 1 , 10 // name broken into 3 parts |
---|
| 96 | #define LDIR_ATTR 11 , 1 // attributes (must be 0x0F) |
---|
| 97 | #define LDIR_TYPE 12 , 1 // directory type (must be 0x00) |
---|
| 98 | #define LDIR_CHKSUM 13 , 1 // checksum of name in short dir |
---|
| 99 | #define LDIR_NAME_2 14 , 12 |
---|
| 100 | #define LDIR_RSVD 26 , 2 // artifact of previous fat (must be 0) |
---|
| 101 | #define LDIR_NAME_3 28 , 4 |
---|
[530] | 102 | /*******************************************************************************/ |
---|
[258] | 103 | |
---|
[530] | 104 | /*********************** DIR_ATTR values (attributes) ************************/ |
---|
[587] | 105 | #define ATTR_READ_ONLY 0x01 |
---|
| 106 | #define ATTR_HIDDEN 0x02 |
---|
| 107 | #define ATTR_SYSTEM 0x04 |
---|
| 108 | #define ATTR_VOLUME_ID 0x08 |
---|
| 109 | #define ATTR_DIRECTORY 0x10 |
---|
| 110 | #define ATTR_ARCHIVE 0x20 |
---|
| 111 | #define ATTR_LONG_NAME_MASK 0x0f // READ_ONLY|HIDDEN|SYSTEM|VOLUME_ID |
---|
[530] | 112 | /*******************************************************************************/ |
---|
[258] | 113 | |
---|
[530] | 114 | /********************* DIR_ORD special values **********************************/ |
---|
[587] | 115 | #define FREE_ENTRY 0xE5 // this entry is free in the directory |
---|
| 116 | #define NO_MORE_ENTRY 0x00 // no more entry in the directory |
---|
[530] | 117 | /*******************************************************************************/ |
---|
[258] | 118 | |
---|
[530] | 119 | /******************** CLuster Index Special Values *****************************/ |
---|
[587] | 120 | #define FREE_CLUSTER 0x00000000 |
---|
| 121 | #define RESERVED_CLUSTER 0x00000001 |
---|
| 122 | #define BAD_CLUSTER 0x0FFFFFF7 |
---|
| 123 | #define END_OF_CHAIN_CLUSTER_MIN 0x0ffffff8 |
---|
| 124 | #define END_OF_CHAIN_CLUSTER_MAX 0x0fffffff |
---|
[530] | 125 | /*******************************************************************************/ |
---|
[258] | 126 | |
---|
[674] | 127 | #define FAT_INITIALIZED 0xBABEF00D |
---|
[587] | 128 | |
---|
| 129 | /******************************************************************************** |
---|
| 130 | This struct defines a non terminal node in a 64-tree implementing a File-Cache |
---|
| 131 | associated to an open file, or the Fat-Cache, associated to the FAT itself. |
---|
| 132 | Each node has 64 children, and we use the void* type, because the children |
---|
| 133 | can be non-terminal (fat_cache_node_t) or terminal (fat_cache_cluster_t). |
---|
| 134 | ********************************************************************************/ |
---|
| 135 | |
---|
| 136 | typedef struct fat_cache_node_s |
---|
[258] | 137 | { |
---|
[587] | 138 | void* children[64]; // pointers on the 64 children |
---|
| 139 | } fat_cache_node_t; |
---|
[258] | 140 | |
---|
[587] | 141 | |
---|
| 142 | /******************************************************************************** |
---|
| 143 | This struct defines a cluster descriptor, that is a leaf cell in a 64-tree. |
---|
| 144 | Each cluster descriptor contains a pointer on a 4K bytes buffer, and the |
---|
| 145 | lba on block device. |
---|
| 146 | ********************************************************************************/ |
---|
| 147 | |
---|
| 148 | typedef struct fat_cache_desc_s |
---|
[258] | 149 | { |
---|
[587] | 150 | unsigned int lba; // cluster lba on block device |
---|
| 151 | unsigned int dirty; // modified if non zero |
---|
| 152 | unsigned char* buffer; // pointer on the 4 Kbytes buffer |
---|
| 153 | } fat_cache_desc_t; |
---|
[258] | 154 | |
---|
[587] | 155 | |
---|
| 156 | /******************************************************************************** |
---|
| 157 | This struct defines a file/directory inode / size = 64 bytes |
---|
| 158 | ********************************************************************************/ |
---|
| 159 | |
---|
| 160 | typedef struct fat_inode_s |
---|
| 161 | { |
---|
| 162 | struct fat_inode_s* parent; // parent directory inode |
---|
| 163 | struct fat_inode_s* next; // next inode in same directory |
---|
| 164 | struct fat_inode_s* child; // first children inode (dir only) |
---|
| 165 | fat_cache_node_t* cache; // pointer on the file_cache root |
---|
| 166 | unsigned int cluster; // first cluster index in FAT |
---|
| 167 | unsigned int size; // number of bytes (file only) |
---|
| 168 | unsigned int count; // number open if file / 0 if dir |
---|
| 169 | unsigned short dentry; // directory entry index in parent |
---|
| 170 | unsigned char levels; // number of levels in file_cache |
---|
| 171 | unsigned char is_dir; // directory if non zero |
---|
| 172 | char name[32]; // file directory name |
---|
| 173 | } fat_inode_t; |
---|
| 174 | |
---|
| 175 | /******************************************************************************** |
---|
| 176 | This struct defines a file descriptor (handler) / size = 16 bytes |
---|
| 177 | ********************************************************************************/ |
---|
| 178 | |
---|
| 179 | typedef struct fat_file_desc_s |
---|
| 180 | { |
---|
| 181 | unsigned int seek; // current offset value (bytes) |
---|
| 182 | fat_inode_t* inode; // pointer on inode |
---|
| 183 | char allocated; // file descriptor allocated |
---|
| 184 | char read_only; // write protected |
---|
| 185 | char reserved[6]; // reserved |
---|
| 186 | } fat_file_desc_t; |
---|
| 187 | |
---|
| 188 | /******************************************************************************** |
---|
| 189 | This struct defines a FAT32 File system descriptor |
---|
| 190 | *******************************************************************************/ |
---|
| 191 | |
---|
| 192 | typedef struct fat_desc_s |
---|
| 193 | { |
---|
| 194 | unsigned char block_buffer[512]; // one block buffer (for FS_INFO) |
---|
| 195 | fat_file_desc_t fd[GIET_OPEN_FILES_MAX]; // file descriptors array |
---|
| 196 | spin_lock_t fat_lock; // global lock protecting FAT |
---|
| 197 | fat_inode_t* inode_tree_root; // Inode-Tree root pointer |
---|
| 198 | fat_cache_node_t* fat_cache_root; // Fat_Cache root pointer |
---|
| 199 | unsigned int fat_cache_levels; // number of levels in Fat-Cache |
---|
| 200 | unsigned int block_buffer_lba; // lba of block in block_buffer |
---|
[674] | 201 | unsigned int initialized; // 0xBABEF00D when FAT initialized |
---|
[587] | 202 | unsigned int sector_size; // must be 512 |
---|
| 203 | unsigned int cluster_size; // must be 4096 |
---|
| 204 | unsigned int fat_lba; // lba of first FAT sector |
---|
| 205 | unsigned int fat_sectors; // number of sectors in FAT region |
---|
| 206 | unsigned int data_lba; // lba of first DATA sector |
---|
| 207 | unsigned int data_sectors; // number of sectors inf DATA region |
---|
| 208 | unsigned int fs_info_lba; // lba of fs_info |
---|
| 209 | unsigned int first_free_cluster; // free cluster with smallest index |
---|
| 210 | unsigned int free_clusters_number; // total number of free clusters |
---|
| 211 | } fat_desc_t; |
---|
| 212 | |
---|
| 213 | |
---|
[530] | 214 | /*********************** Extern Functions *************************************/ |
---|
[258] | 215 | |
---|
[587] | 216 | extern int _fat_init(); |
---|
[258] | 217 | |
---|
[587] | 218 | extern int _fat_open( char* pathname, // path from root |
---|
| 219 | unsigned int flags ); // O_CREATE/O_RDONLY |
---|
[258] | 220 | |
---|
[587] | 221 | extern int _fat_close( unsigned int fd_id ); // file descriptor |
---|
[258] | 222 | |
---|
[658] | 223 | extern int _fat_file_info( unsigned int fd_id, // file descriptor |
---|
| 224 | fat_file_info_t* info ); // file info struct |
---|
[258] | 225 | |
---|
[587] | 226 | extern int _fat_read( unsigned int fd_id, // file descriptor |
---|
| 227 | void* buffer, // destination buffer |
---|
| 228 | unsigned int count ); // number of bytes |
---|
[258] | 229 | |
---|
[587] | 230 | extern int _fat_write( unsigned int fd_id, // file descriptor |
---|
| 231 | void* buffer, // source buffer |
---|
| 232 | unsigned int count ); // number of bytes |
---|
[258] | 233 | |
---|
[587] | 234 | extern int _fat_lseek( unsigned int fd_id, // file descriptor |
---|
| 235 | unsigned int offset, // new offset value |
---|
| 236 | unsigned int whence ); // command type |
---|
[260] | 237 | |
---|
[587] | 238 | extern int _fat_remove( char* pathname, // path from root |
---|
| 239 | unsigned int should_be_dir ); // for checking |
---|
[258] | 240 | |
---|
[587] | 241 | extern int _fat_rename( char* old_path, // path from root |
---|
| 242 | char* new_path ); // path from root |
---|
[258] | 243 | |
---|
[587] | 244 | extern int _fat_mkdir( char* pathname ); // path from root |
---|
[258] | 245 | |
---|
[658] | 246 | extern int _fat_opendir( char* pathname ); // path from root |
---|
| 247 | |
---|
| 248 | extern int _fat_closedir( unsigned int fd_id ); // file descriptor |
---|
| 249 | |
---|
| 250 | extern int _fat_readdir( unsigned int fd_id, // file descriptor |
---|
| 251 | fat_dirent_t* entry ); // directory entry |
---|
| 252 | |
---|
[587] | 253 | extern int _fat_load_no_cache( char* pathname, // path from root |
---|
| 254 | unsigned int buffer_vbase, // buffer base |
---|
| 255 | unsigned int buffer_size ); // buffer size |
---|
| 256 | |
---|
[530] | 257 | /*******************************************************************************/ |
---|
[258] | 258 | |
---|
| 259 | |
---|
| 260 | #endif |
---|
| 261 | |
---|
| 262 | |
---|
| 263 | // Local Variables: |
---|
| 264 | // tab-width: 4 |
---|
| 265 | // c-basic-offset: 4 |
---|
| 266 | // c-file-offsets:((innamespace . 0)(inline-open . 0)) |
---|
| 267 | // indent-tabs-mode: nil |
---|
| 268 | // End: |
---|
| 269 | // vim: filetype=c:expandtab:shiftwidth=4:tabstop=4:softtabstop=4 |
---|
| 270 | |
---|