1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef _UAPI_LINUX_MSDOS_FS_H 3 #define _UAPI_LINUX_MSDOS_FS_H 4 5 #include <linux/types.h> 6 #include <linux/magic.h> 7 #include <asm/byteorder.h> 8 9 /* 10 * The MS-DOS filesystem constants/structures 11 */ 12 13 #define SECTOR_SIZE 512 /* sector size (bytes) */ 14 #define SECTOR_BITS 9 /* log2(SECTOR_SIZE) */ 15 #define MSDOS_DPB (MSDOS_DPS) /* dir entries per block */ 16 #define MSDOS_DPB_BITS 4 /* log2(MSDOS_DPB) */ 17 #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) 18 #define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */ 19 #define MSDOS_LONGNAME 256 /* maximum name length */ 20 #define CF_LE_W(v) le16_to_cpu(v) 21 #define CF_LE_L(v) le32_to_cpu(v) 22 #define CT_LE_W(v) cpu_to_le16(v) 23 #define CT_LE_L(v) cpu_to_le32(v) 24 25 #define MSDOS_ROOT_INO 1 /* The root inode number */ 26 #define MSDOS_FSINFO_INO 2 /* Used for managing the FSINFO block */ 27 28 #define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */ 29 30 /* directory limit */ 31 #define FAT_MAX_DIR_ENTRIES (65536) 32 #define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS) 33 34 #define ATTR_NONE 0 /* no attribute bits */ 35 #define ATTR_RO 1 /* read-only */ 36 #define ATTR_HIDDEN 2 /* hidden */ 37 #define ATTR_SYS 4 /* system */ 38 #define ATTR_VOLUME 8 /* volume label */ 39 #define ATTR_DIR 16 /* directory */ 40 #define ATTR_ARCH 32 /* archived */ 41 42 /* attribute bits that are copied "as is" */ 43 #define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN) 44 /* bits that are used by the Windows 95/Windows NT extended FAT */ 45 #define ATTR_EXT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME) 46 47 #define CASE_LOWER_BASE 8 /* base is lower case */ 48 #define CASE_LOWER_EXT 16 /* extension is lower case */ 49 50 #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */ 51 #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG) 52 53 #define FAT_LFN_LEN 255 /* maximum long name length */ 54 #define MSDOS_NAME 11 /* maximum name length */ 55 #define MSDOS_SLOTS 21 /* max # of slots for short and long names */ 56 #define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */ 57 #define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */ 58 59 #define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \ 60 MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x)) 61 62 /* start of data cluster's entry (number of reserved clusters) */ 63 #define FAT_START_ENT 2 64 65 /* maximum number of clusters */ 66 #define MAX_FAT12 0xFF4 67 #define MAX_FAT16 0xFFF4 68 #define MAX_FAT32 0x0FFFFFF6 69 #define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \ 70 MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12) 71 72 /* bad cluster mark */ 73 #define BAD_FAT12 0xFF7 74 #define BAD_FAT16 0xFFF7 75 #define BAD_FAT32 0x0FFFFFF7 76 77 /* standard EOF */ 78 #define EOF_FAT12 0xFFF 79 #define EOF_FAT16 0xFFFF 80 #define EOF_FAT32 0x0FFFFFFF 81 82 #define FAT_ENT_FREE (0) 83 #define FAT_ENT_BAD (BAD_FAT32) 84 #define FAT_ENT_EOF (EOF_FAT32) 85 86 #define FAT_FSINFO_SIG1 0x41615252 87 #define FAT_FSINFO_SIG2 0x61417272 88 #define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \ 89 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2) 90 91 #define FAT_STATE_DIRTY 0x01 92 93 struct __fat_dirent { 94 long d_ino; 95 __kernel_off_t d_off; 96 unsigned short d_reclen; 97 char d_name[256]; /* We must not include limits.h! */ 98 }; 99 100 /* 101 * ioctl commands 102 */ 103 #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct __fat_dirent[2]) 104 #define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct __fat_dirent[2]) 105 /* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */ 106 #define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32) 107 #define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32) 108 /*Android kernel has used 0x12, so we use 0x13*/ 109 #define FAT_IOCTL_GET_VOLUME_ID _IOR('r', 0x13, __u32) 110 111 struct fat_boot_sector { 112 __u8 ignored[3]; /* Boot strap short or near jump */ 113 __u8 system_id[8]; /* Name - can be used to special case 114 partition manager volumes */ 115 __u8 sector_size[2]; /* bytes per logical sector */ 116 __u8 sec_per_clus; /* sectors/cluster */ 117 __le16 reserved; /* reserved sectors */ 118 __u8 fats; /* number of FATs */ 119 __u8 dir_entries[2]; /* root directory entries */ 120 __u8 sectors[2]; /* number of sectors */ 121 __u8 media; /* media code */ 122 __le16 fat_length; /* sectors/FAT */ 123 __le16 secs_track; /* sectors per track */ 124 __le16 heads; /* number of heads */ 125 __le32 hidden; /* hidden sectors (unused) */ 126 __le32 total_sect; /* number of sectors (if sectors == 0) */ 127 128 union { 129 struct { 130 /* Extended BPB Fields for FAT16 */ 131 __u8 drive_number; /* Physical drive number */ 132 __u8 state; /* undocumented, but used 133 for mount state. */ 134 __u8 signature; /* extended boot signature */ 135 __u8 vol_id[4]; /* volume ID */ 136 __u8 vol_label[11]; /* volume label */ 137 __u8 fs_type[8]; /* file system type */ 138 /* other fields are not added here */ 139 } fat16; 140 141 struct { 142 /* only used by FAT32 */ 143 __le32 length; /* sectors/FAT */ 144 __le16 flags; /* bit 8: fat mirroring, 145 low 4: active fat */ 146 __u8 version[2]; /* major, minor filesystem 147 version */ 148 __le32 root_cluster; /* first cluster in 149 root directory */ 150 __le16 info_sector; /* filesystem info sector */ 151 __le16 backup_boot; /* backup boot sector */ 152 __le16 reserved2[6]; /* Unused */ 153 /* Extended BPB Fields for FAT32 */ 154 __u8 drive_number; /* Physical drive number */ 155 __u8 state; /* undocumented, but used 156 for mount state. */ 157 __u8 signature; /* extended boot signature */ 158 __u8 vol_id[4]; /* volume ID */ 159 __u8 vol_label[11]; /* volume label */ 160 __u8 fs_type[8]; /* file system type */ 161 /* other fields are not added here */ 162 } fat32; 163 }; 164 }; 165 166 struct fat_boot_fsinfo { 167 __le32 signature1; /* 0x41615252L */ 168 __le32 reserved1[120]; /* Nothing as far as I can tell */ 169 __le32 signature2; /* 0x61417272L */ 170 __le32 free_clusters; /* Free cluster count. -1 if unknown */ 171 __le32 next_cluster; /* Most recently allocated cluster */ 172 __le32 reserved2[4]; 173 }; 174 175 struct msdos_dir_entry { 176 __u8 name[MSDOS_NAME];/* name and extension */ 177 __u8 attr; /* attribute bits */ 178 __u8 lcase; /* Case for base and extension */ 179 __u8 ctime_cs; /* Creation time, centiseconds (0-199) */ 180 __le16 ctime; /* Creation time */ 181 __le16 cdate; /* Creation date */ 182 __le16 adate; /* Last access date */ 183 __le16 starthi; /* High 16 bits of cluster in FAT32 */ 184 __le16 time,date,start;/* time, date and first cluster */ 185 __le32 size; /* file size (in bytes) */ 186 }; 187 188 /* Up to 13 characters of the name */ 189 struct msdos_dir_slot { 190 __u8 id; /* sequence number for slot */ 191 __u8 name0_4[10]; /* first 5 characters in name */ 192 __u8 attr; /* attribute byte */ 193 __u8 reserved; /* always 0 */ 194 __u8 alias_checksum; /* checksum for 8.3 alias */ 195 __u8 name5_10[12]; /* 6 more characters in name */ 196 __le16 start; /* starting cluster number, 0 in long slots */ 197 __u8 name11_12[4]; /* last 2 characters in name */ 198 }; 199 200 #endif /* _UAPI_LINUX_MSDOS_FS_H */ 201