1 #ifndef _LINUX_MSDOS_FS_H 2 #define _LINUX_MSDOS_FS_H 3 4 #include <linux/types.h> 5 #include <linux/magic.h> 6 #include <asm/byteorder.h> 7 8 /* 9 * The MS-DOS filesystem constants/structures 10 */ 11 12 #define SECTOR_SIZE 512 /* sector size (bytes) */ 13 #define SECTOR_BITS 9 /* log2(SECTOR_SIZE) */ 14 #define MSDOS_DPB (MSDOS_DPS) /* dir entries per block */ 15 #define MSDOS_DPB_BITS 4 /* log2(MSDOS_DPB) */ 16 #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) 17 #define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */ 18 #define CF_LE_W(v) le16_to_cpu(v) 19 #define CF_LE_L(v) le32_to_cpu(v) 20 #define CT_LE_W(v) cpu_to_le16(v) 21 #define CT_LE_L(v) cpu_to_le32(v) 22 23 24 #define MSDOS_ROOT_INO 1 /* == MINIX_ROOT_INO */ 25 #define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */ 26 27 /* directory limit */ 28 #define FAT_MAX_DIR_ENTRIES (65536) 29 #define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS) 30 31 #define ATTR_NONE 0 /* no attribute bits */ 32 #define ATTR_RO 1 /* read-only */ 33 #define ATTR_HIDDEN 2 /* hidden */ 34 #define ATTR_SYS 4 /* system */ 35 #define ATTR_VOLUME 8 /* volume label */ 36 #define ATTR_DIR 16 /* directory */ 37 #define ATTR_ARCH 32 /* archived */ 38 39 /* attribute bits that are copied "as is" */ 40 #define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN) 41 /* bits that are used by the Windows 95/Windows NT extended FAT */ 42 #define ATTR_EXT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME) 43 44 #define CASE_LOWER_BASE 8 /* base is lower case */ 45 #define CASE_LOWER_EXT 16 /* extension is lower case */ 46 47 #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */ 48 #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG) 49 50 #define MSDOS_NAME 11 /* maximum name length */ 51 #define MSDOS_LONGNAME 256 /* maximum name length */ 52 #define MSDOS_SLOTS 21 /* max # of slots for short and long names */ 53 #define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */ 54 #define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */ 55 56 #define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \ 57 MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x)) 58 59 /* start of data cluster's entry (number of reserved clusters) */ 60 #define FAT_START_ENT 2 61 62 /* maximum number of clusters */ 63 #define MAX_FAT12 0xFF4 64 #define MAX_FAT16 0xFFF4 65 #define MAX_FAT32 0x0FFFFFF6 66 #define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \ 67 MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12) 68 69 /* bad cluster mark */ 70 #define BAD_FAT12 0xFF7 71 #define BAD_FAT16 0xFFF7 72 #define BAD_FAT32 0x0FFFFFF7 73 74 /* standard EOF */ 75 #define EOF_FAT12 0xFFF 76 #define EOF_FAT16 0xFFFF 77 #define EOF_FAT32 0x0FFFFFFF 78 79 #define FAT_ENT_FREE (0) 80 #define FAT_ENT_BAD (BAD_FAT32) 81 #define FAT_ENT_EOF (EOF_FAT32) 82 83 #define FAT_FSINFO_SIG1 0x41615252 84 #define FAT_FSINFO_SIG2 0x61417272 85 #define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \ 86 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2) 87 88 struct __fat_dirent { 89 long d_ino; 90 __kernel_off_t d_off; 91 unsigned short d_reclen; 92 char d_name[256]; /* We must not include limits.h! */ 93 }; 94 95 /* 96 * ioctl commands 97 */ 98 #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct __fat_dirent[2]) 99 #define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct __fat_dirent[2]) 100 /* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */ 101 #define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32) 102 #define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32) 103 104 struct fat_boot_sector { 105 __u8 ignored[3]; /* Boot strap short or near jump */ 106 __u8 system_id[8]; /* Name - can be used to special case 107 partition manager volumes */ 108 __u8 sector_size[2]; /* bytes per logical sector */ 109 __u8 sec_per_clus; /* sectors/cluster */ 110 __le16 reserved; /* reserved sectors */ 111 __u8 fats; /* number of FATs */ 112 __u8 dir_entries[2]; /* root directory entries */ 113 __u8 sectors[2]; /* number of sectors */ 114 __u8 media; /* media code */ 115 __le16 fat_length; /* sectors/FAT */ 116 __le16 secs_track; /* sectors per track */ 117 __le16 heads; /* number of heads */ 118 __le32 hidden; /* hidden sectors (unused) */ 119 __le32 total_sect; /* number of sectors (if sectors == 0) */ 120 121 /* The following fields are only used by FAT32 */ 122 __le32 fat32_length; /* sectors/FAT */ 123 __le16 flags; /* bit 8: fat mirroring, low 4: active fat */ 124 __u8 version[2]; /* major, minor filesystem version */ 125 __le32 root_cluster; /* first cluster in root directory */ 126 __le16 info_sector; /* filesystem info sector */ 127 __le16 backup_boot; /* backup boot sector */ 128 __le16 reserved2[6]; /* Unused */ 129 }; 130 131 struct fat_boot_fsinfo { 132 __le32 signature1; /* 0x41615252L */ 133 __le32 reserved1[120]; /* Nothing as far as I can tell */ 134 __le32 signature2; /* 0x61417272L */ 135 __le32 free_clusters; /* Free cluster count. -1 if unknown */ 136 __le32 next_cluster; /* Most recently allocated cluster */ 137 __le32 reserved2[4]; 138 }; 139 140 struct msdos_dir_entry { 141 __u8 name[MSDOS_NAME];/* name and extension */ 142 __u8 attr; /* attribute bits */ 143 __u8 lcase; /* Case for base and extension */ 144 __u8 ctime_cs; /* Creation time, centiseconds (0-199) */ 145 __le16 ctime; /* Creation time */ 146 __le16 cdate; /* Creation date */ 147 __le16 adate; /* Last access date */ 148 __le16 starthi; /* High 16 bits of cluster in FAT32 */ 149 __le16 time,date,start;/* time, date and first cluster */ 150 __le32 size; /* file size (in bytes) */ 151 }; 152 153 /* Up to 13 characters of the name */ 154 struct msdos_dir_slot { 155 __u8 id; /* sequence number for slot */ 156 __u8 name0_4[10]; /* first 5 characters in name */ 157 __u8 attr; /* attribute byte */ 158 __u8 reserved; /* always 0 */ 159 __u8 alias_checksum; /* checksum for 8.3 alias */ 160 __u8 name5_10[12]; /* 6 more characters in name */ 161 __le16 start; /* starting cluster number, 0 in long slots */ 162 __u8 name11_12[4]; /* last 2 characters in name */ 163 }; 164 165 #ifdef __KERNEL__ 166 /* media of boot sector */ 167 static inline int fat_valid_media(u8 media) 168 { 169 return 0xf8 <= media || media == 0xf0; 170 } 171 #endif /* !__KERNEL__ */ 172 #endif /* !_LINUX_MSDOS_FS_H */ 173