Linux kernel mirror (for testing)
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linux
1#ifndef _UAPI_LINUX_MSDOS_FS_H
2#define _UAPI_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 MSDOS_LONGNAME 256 /* maximum name length */
19#define CF_LE_W(v) le16_to_cpu(v)
20#define CF_LE_L(v) le32_to_cpu(v)
21#define CT_LE_W(v) cpu_to_le16(v)
22#define CT_LE_L(v) cpu_to_le32(v)
23
24#define MSDOS_ROOT_INO 1 /* The root inode number */
25#define MSDOS_FSINFO_INO 2 /* Used for managing the FSINFO block */
26
27#define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */
28
29/* directory limit */
30#define FAT_MAX_DIR_ENTRIES (65536)
31#define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS)
32
33#define ATTR_NONE 0 /* no attribute bits */
34#define ATTR_RO 1 /* read-only */
35#define ATTR_HIDDEN 2 /* hidden */
36#define ATTR_SYS 4 /* system */
37#define ATTR_VOLUME 8 /* volume label */
38#define ATTR_DIR 16 /* directory */
39#define ATTR_ARCH 32 /* archived */
40
41/* attribute bits that are copied "as is" */
42#define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN)
43/* bits that are used by the Windows 95/Windows NT extended FAT */
44#define ATTR_EXT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME)
45
46#define CASE_LOWER_BASE 8 /* base is lower case */
47#define CASE_LOWER_EXT 16 /* extension is lower case */
48
49#define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */
50#define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG)
51
52#define FAT_LFN_LEN 255 /* maximum long name length */
53#define MSDOS_NAME 11 /* maximum name length */
54#define MSDOS_SLOTS 21 /* max # of slots for short and long names */
55#define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */
56#define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */
57
58#define FAT_FIRST_ENT(s, x) ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \
59 MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x))
60
61/* start of data cluster's entry (number of reserved clusters) */
62#define FAT_START_ENT 2
63
64/* maximum number of clusters */
65#define MAX_FAT12 0xFF4
66#define MAX_FAT16 0xFFF4
67#define MAX_FAT32 0x0FFFFFF6
68#define MAX_FAT(s) (MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \
69 MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12)
70
71/* bad cluster mark */
72#define BAD_FAT12 0xFF7
73#define BAD_FAT16 0xFFF7
74#define BAD_FAT32 0x0FFFFFF7
75
76/* standard EOF */
77#define EOF_FAT12 0xFFF
78#define EOF_FAT16 0xFFFF
79#define EOF_FAT32 0x0FFFFFFF
80
81#define FAT_ENT_FREE (0)
82#define FAT_ENT_BAD (BAD_FAT32)
83#define FAT_ENT_EOF (EOF_FAT32)
84
85#define FAT_FSINFO_SIG1 0x41615252
86#define FAT_FSINFO_SIG2 0x61417272
87#define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \
88 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2)
89
90struct __fat_dirent {
91 long d_ino;
92 __kernel_off_t d_off;
93 unsigned short d_reclen;
94 char d_name[256]; /* We must not include limits.h! */
95};
96
97/*
98 * ioctl commands
99 */
100#define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct __fat_dirent[2])
101#define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct __fat_dirent[2])
102/* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */
103#define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32)
104#define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32)
105
106struct fat_boot_sector {
107 __u8 ignored[3]; /* Boot strap short or near jump */
108 __u8 system_id[8]; /* Name - can be used to special case
109 partition manager volumes */
110 __u8 sector_size[2]; /* bytes per logical sector */
111 __u8 sec_per_clus; /* sectors/cluster */
112 __le16 reserved; /* reserved sectors */
113 __u8 fats; /* number of FATs */
114 __u8 dir_entries[2]; /* root directory entries */
115 __u8 sectors[2]; /* number of sectors */
116 __u8 media; /* media code */
117 __le16 fat_length; /* sectors/FAT */
118 __le16 secs_track; /* sectors per track */
119 __le16 heads; /* number of heads */
120 __le32 hidden; /* hidden sectors (unused) */
121 __le32 total_sect; /* number of sectors (if sectors == 0) */
122
123 /* The following fields are only used by FAT32 */
124 __le32 fat32_length; /* sectors/FAT */
125 __le16 flags; /* bit 8: fat mirroring, low 4: active fat */
126 __u8 version[2]; /* major, minor filesystem version */
127 __le32 root_cluster; /* first cluster in root directory */
128 __le16 info_sector; /* filesystem info sector */
129 __le16 backup_boot; /* backup boot sector */
130 __le16 reserved2[6]; /* Unused */
131};
132
133struct fat_boot_fsinfo {
134 __le32 signature1; /* 0x41615252L */
135 __le32 reserved1[120]; /* Nothing as far as I can tell */
136 __le32 signature2; /* 0x61417272L */
137 __le32 free_clusters; /* Free cluster count. -1 if unknown */
138 __le32 next_cluster; /* Most recently allocated cluster */
139 __le32 reserved2[4];
140};
141
142struct msdos_dir_entry {
143 __u8 name[MSDOS_NAME];/* name and extension */
144 __u8 attr; /* attribute bits */
145 __u8 lcase; /* Case for base and extension */
146 __u8 ctime_cs; /* Creation time, centiseconds (0-199) */
147 __le16 ctime; /* Creation time */
148 __le16 cdate; /* Creation date */
149 __le16 adate; /* Last access date */
150 __le16 starthi; /* High 16 bits of cluster in FAT32 */
151 __le16 time,date,start;/* time, date and first cluster */
152 __le32 size; /* file size (in bytes) */
153};
154
155/* Up to 13 characters of the name */
156struct msdos_dir_slot {
157 __u8 id; /* sequence number for slot */
158 __u8 name0_4[10]; /* first 5 characters in name */
159 __u8 attr; /* attribute byte */
160 __u8 reserved; /* always 0 */
161 __u8 alias_checksum; /* checksum for 8.3 alias */
162 __u8 name5_10[12]; /* 6 more characters in name */
163 __le16 start; /* starting cluster number, 0 in long slots */
164 __u8 name11_12[4]; /* last 2 characters in name */
165};
166
167#endif /* _UAPI_LINUX_MSDOS_FS_H */