1 #ifndef _LINUX_MSDOS_FS_H 2 #define _LINUX_MSDOS_FS_H 3 4 #include <linux/magic.h> 5 6 /* 7 * The MS-DOS filesystem constants/structures 8 */ 9 #include <asm/byteorder.h> 10 11 #define SECTOR_SIZE 512 /* sector size (bytes) */ 12 #define SECTOR_BITS 9 /* log2(SECTOR_SIZE) */ 13 #define MSDOS_DPB (MSDOS_DPS) /* dir entries per block */ 14 #define MSDOS_DPB_BITS 4 /* log2(MSDOS_DPB) */ 15 #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) 16 #define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */ 17 #define CF_LE_W(v) le16_to_cpu(v) 18 #define CF_LE_L(v) le32_to_cpu(v) 19 #define CT_LE_W(v) cpu_to_le16(v) 20 #define CT_LE_L(v) cpu_to_le32(v) 21 22 23 #define MSDOS_ROOT_INO 1 /* == MINIX_ROOT_INO */ 24 #define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */ 25 26 /* directory limit */ 27 #define FAT_MAX_DIR_ENTRIES (65536) 28 #define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS) 29 30 #define ATTR_NONE 0 /* no attribute bits */ 31 #define ATTR_RO 1 /* read-only */ 32 #define ATTR_HIDDEN 2 /* hidden */ 33 #define ATTR_SYS 4 /* system */ 34 #define ATTR_VOLUME 8 /* volume label */ 35 #define ATTR_DIR 16 /* directory */ 36 #define ATTR_ARCH 32 /* archived */ 37 38 /* attribute bits that are copied "as is" */ 39 #define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN) 40 /* bits that are used by the Windows 95/Windows NT extended FAT */ 41 #define ATTR_EXT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME) 42 43 #define CASE_LOWER_BASE 8 /* base is lower case */ 44 #define CASE_LOWER_EXT 16 /* extension is lower case */ 45 46 #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */ 47 #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG) 48 49 /* valid file mode bits */ 50 #define MSDOS_VALID_MODE (S_IFREG | S_IFDIR | S_IRWXU | S_IRWXG | S_IRWXO) 51 /* Convert attribute bits and a mask to the UNIX mode. */ 52 #define MSDOS_MKMODE(a, m) (m & (a & ATTR_RO ? S_IRUGO|S_IXUGO : S_IRWXUGO)) 53 54 #define MSDOS_NAME 11 /* maximum name length */ 55 #define MSDOS_LONGNAME 256 /* maximum name length */ 56 #define MSDOS_SLOTS 21 /* max # of slots for short and long names */ 57 #define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */ 58 #define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */ 59 60 /* media of boot sector */ 61 #define FAT_VALID_MEDIA(x) ((0xF8 <= (x) && (x) <= 0xFF) || (x) == 0xF0) 62 #define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \ 63 MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x)) 64 65 /* start of data cluster's entry (number of reserved clusters) */ 66 #define FAT_START_ENT 2 67 68 /* maximum number of clusters */ 69 #define MAX_FAT12 0xFF4 70 #define MAX_FAT16 0xFFF4 71 #define MAX_FAT32 0x0FFFFFF6 72 #define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \ 73 MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12) 74 75 /* bad cluster mark */ 76 #define BAD_FAT12 0xFF7 77 #define BAD_FAT16 0xFFF7 78 #define BAD_FAT32 0x0FFFFFF7 79 80 /* standard EOF */ 81 #define EOF_FAT12 0xFFF 82 #define EOF_FAT16 0xFFFF 83 #define EOF_FAT32 0x0FFFFFFF 84 85 #define FAT_ENT_FREE (0) 86 #define FAT_ENT_BAD (BAD_FAT32) 87 #define FAT_ENT_EOF (EOF_FAT32) 88 89 #define FAT_FSINFO_SIG1 0x41615252 90 #define FAT_FSINFO_SIG2 0x61417272 91 #define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \ 92 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2) 93 94 /* 95 * ioctl commands 96 */ 97 #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct dirent [2]) 98 #define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct dirent [2]) 99 /* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */ 100 #define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32) 101 #define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32) 102 103 /* 104 * vfat shortname flags 105 */ 106 #define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */ 107 #define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */ 108 #define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */ 109 #define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */ 110 #define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */ 111 112 struct fat_boot_sector { 113 __u8 ignored[3]; /* Boot strap short or near jump */ 114 __u8 system_id[8]; /* Name - can be used to special case 115 partition manager volumes */ 116 __u8 sector_size[2]; /* bytes per logical sector */ 117 __u8 sec_per_clus; /* sectors/cluster */ 118 __le16 reserved; /* reserved sectors */ 119 __u8 fats; /* number of FATs */ 120 __u8 dir_entries[2]; /* root directory entries */ 121 __u8 sectors[2]; /* number of sectors */ 122 __u8 media; /* media code */ 123 __le16 fat_length; /* sectors/FAT */ 124 __le16 secs_track; /* sectors per track */ 125 __le16 heads; /* number of heads */ 126 __le32 hidden; /* hidden sectors (unused) */ 127 __le32 total_sect; /* number of sectors (if sectors == 0) */ 128 129 /* The following fields are only used by FAT32 */ 130 __le32 fat32_length; /* sectors/FAT */ 131 __le16 flags; /* bit 8: fat mirroring, low 4: active fat */ 132 __u8 version[2]; /* major, minor filesystem version */ 133 __le32 root_cluster; /* first cluster in root directory */ 134 __le16 info_sector; /* filesystem info sector */ 135 __le16 backup_boot; /* backup boot sector */ 136 __le16 reserved2[6]; /* Unused */ 137 }; 138 139 struct fat_boot_fsinfo { 140 __le32 signature1; /* 0x41615252L */ 141 __le32 reserved1[120]; /* Nothing as far as I can tell */ 142 __le32 signature2; /* 0x61417272L */ 143 __le32 free_clusters; /* Free cluster count. -1 if unknown */ 144 __le32 next_cluster; /* Most recently allocated cluster */ 145 __le32 reserved2[4]; 146 }; 147 148 struct msdos_dir_entry { 149 __u8 name[MSDOS_NAME];/* name and extension */ 150 __u8 attr; /* attribute bits */ 151 __u8 lcase; /* Case for base and extension */ 152 __u8 ctime_cs; /* Creation time, centiseconds (0-199) */ 153 __le16 ctime; /* Creation time */ 154 __le16 cdate; /* Creation date */ 155 __le16 adate; /* Last access date */ 156 __le16 starthi; /* High 16 bits of cluster in FAT32 */ 157 __le16 time,date,start;/* time, date and first cluster */ 158 __le32 size; /* file size (in bytes) */ 159 }; 160 161 /* Up to 13 characters of the name */ 162 struct msdos_dir_slot { 163 __u8 id; /* sequence number for slot */ 164 __u8 name0_4[10]; /* first 5 characters in name */ 165 __u8 attr; /* attribute byte */ 166 __u8 reserved; /* always 0 */ 167 __u8 alias_checksum; /* checksum for 8.3 alias */ 168 __u8 name5_10[12]; /* 6 more characters in name */ 169 __le16 start; /* starting cluster number, 0 in long slots */ 170 __u8 name11_12[4]; /* last 2 characters in name */ 171 }; 172 173 struct fat_slot_info { 174 loff_t i_pos; /* on-disk position of directory entry */ 175 loff_t slot_off; /* offset for slot or de start */ 176 int nr_slots; /* number of slots + 1(de) in filename */ 177 struct msdos_dir_entry *de; 178 struct buffer_head *bh; 179 }; 180 181 182 #endif 183