include/linux/msdos_fs.h
changeset 0 aa628870c1d3
child 2 d1f6d8b6f81c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/linux/msdos_fs.h	Sun Jan 11 20:20:11 2009 +0100
@@ -0,0 +1,171 @@
+#ifndef _LINUX_MSDOS_FS_H
+#define _LINUX_MSDOS_FS_H
+
+#include <linux/magic.h>
+#include <asm/byteorder.h>
+
+/*
+ * The MS-DOS filesystem constants/structures
+ */
+
+#define SECTOR_SIZE	512		/* sector size (bytes) */
+#define SECTOR_BITS	9		/* log2(SECTOR_SIZE) */
+#define MSDOS_DPB	(MSDOS_DPS)	/* dir entries per block */
+#define MSDOS_DPB_BITS	4		/* log2(MSDOS_DPB) */
+#define MSDOS_DPS	(SECTOR_SIZE / sizeof(struct msdos_dir_entry))
+#define MSDOS_DPS_BITS	4		/* log2(MSDOS_DPS) */
+#define CF_LE_W(v)	le16_to_cpu(v)
+#define CF_LE_L(v)	le32_to_cpu(v)
+#define CT_LE_W(v)	cpu_to_le16(v)
+#define CT_LE_L(v)	cpu_to_le32(v)
+
+
+#define MSDOS_ROOT_INO	1	/* == MINIX_ROOT_INO */
+#define MSDOS_DIR_BITS	5	/* log2(sizeof(struct msdos_dir_entry)) */
+
+/* directory limit */
+#define FAT_MAX_DIR_ENTRIES	(65536)
+#define FAT_MAX_DIR_SIZE	(FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS)
+
+#define ATTR_NONE	0	/* no attribute bits */
+#define ATTR_RO		1	/* read-only */
+#define ATTR_HIDDEN	2	/* hidden */
+#define ATTR_SYS	4	/* system */
+#define ATTR_VOLUME	8	/* volume label */
+#define ATTR_DIR	16	/* directory */
+#define ATTR_ARCH	32	/* archived */
+
+/* attribute bits that are copied "as is" */
+#define ATTR_UNUSED	(ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN)
+/* bits that are used by the Windows 95/Windows NT extended FAT */
+#define ATTR_EXT	(ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME)
+
+#define CASE_LOWER_BASE	8	/* base is lower case */
+#define CASE_LOWER_EXT	16	/* extension is lower case */
+
+#define DELETED_FLAG	0xe5	/* marks file as deleted when in name[0] */
+#define IS_FREE(n)	(!*(n) || *(n) == DELETED_FLAG)
+
+#define MSDOS_NAME	11	/* maximum name length */
+#define MSDOS_LONGNAME	256	/* maximum name length */
+#define MSDOS_SLOTS	21	/* max # of slots for short and long names */
+#define MSDOS_DOT	".          "	/* ".", padded to MSDOS_NAME chars */
+#define MSDOS_DOTDOT	"..         "	/* "..", padded to MSDOS_NAME chars */
+
+#define FAT_FIRST_ENT(s, x)	((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \
+	MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x))
+
+/* start of data cluster's entry (number of reserved clusters) */
+#define FAT_START_ENT	2
+
+/* maximum number of clusters */
+#define MAX_FAT12	0xFF4
+#define MAX_FAT16	0xFFF4
+#define MAX_FAT32	0x0FFFFFF6
+#define MAX_FAT(s)	(MSDOS_SB(s)->fat_bits == 32 ? MAX_FAT32 : \
+	MSDOS_SB(s)->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12)
+
+/* bad cluster mark */
+#define BAD_FAT12	0xFF7
+#define BAD_FAT16	0xFFF7
+#define BAD_FAT32	0x0FFFFFF7
+
+/* standard EOF */
+#define EOF_FAT12	0xFFF
+#define EOF_FAT16	0xFFFF
+#define EOF_FAT32	0x0FFFFFFF
+
+#define FAT_ENT_FREE	(0)
+#define FAT_ENT_BAD	(BAD_FAT32)
+#define FAT_ENT_EOF	(EOF_FAT32)
+
+#define FAT_FSINFO_SIG1	0x41615252
+#define FAT_FSINFO_SIG2	0x61417272
+#define IS_FSINFO(x)	(le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \
+			 && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2)
+
+struct __fat_dirent {
+	long		d_ino;
+	__kernel_off_t	d_off;
+	unsigned short	d_reclen;
+	char		d_name[256]; /* We must not include limits.h! */
+};
+
+/*
+ * ioctl commands
+ */
+#define VFAT_IOCTL_READDIR_BOTH		_IOR('r', 1, struct __fat_dirent[2])
+#define VFAT_IOCTL_READDIR_SHORT	_IOR('r', 2, struct __fat_dirent[2])
+/* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */
+#define FAT_IOCTL_GET_ATTRIBUTES	_IOR('r', 0x10, __u32)
+#define FAT_IOCTL_SET_ATTRIBUTES	_IOW('r', 0x11, __u32)
+
+struct fat_boot_sector {
+	__u8	ignored[3];	/* Boot strap short or near jump */
+	__u8	system_id[8];	/* Name - can be used to special case
+				   partition manager volumes */
+	__u8	sector_size[2];	/* bytes per logical sector */
+	__u8	sec_per_clus;	/* sectors/cluster */
+	__le16	reserved;	/* reserved sectors */
+	__u8	fats;		/* number of FATs */
+	__u8	dir_entries[2];	/* root directory entries */
+	__u8	sectors[2];	/* number of sectors */
+	__u8	media;		/* media code */
+	__le16	fat_length;	/* sectors/FAT */
+	__le16	secs_track;	/* sectors per track */
+	__le16	heads;		/* number of heads */
+	__le32	hidden;		/* hidden sectors (unused) */
+	__le32	total_sect;	/* number of sectors (if sectors == 0) */
+
+	/* The following fields are only used by FAT32 */
+	__le32	fat32_length;	/* sectors/FAT */
+	__le16	flags;		/* bit 8: fat mirroring, low 4: active fat */
+	__u8	version[2];	/* major, minor filesystem version */
+	__le32	root_cluster;	/* first cluster in root directory */
+	__le16	info_sector;	/* filesystem info sector */
+	__le16	backup_boot;	/* backup boot sector */
+	__le16	reserved2[6];	/* Unused */
+};
+
+struct fat_boot_fsinfo {
+	__le32   signature1;	/* 0x41615252L */
+	__le32   reserved1[120];	/* Nothing as far as I can tell */
+	__le32   signature2;	/* 0x61417272L */
+	__le32   free_clusters;	/* Free cluster count.  -1 if unknown */
+	__le32   next_cluster;	/* Most recently allocated cluster */
+	__le32   reserved2[4];
+};
+
+struct msdos_dir_entry {
+	__u8	name[MSDOS_NAME];/* name and extension */
+	__u8	attr;		/* attribute bits */
+	__u8    lcase;		/* Case for base and extension */
+	__u8	ctime_cs;	/* Creation time, centiseconds (0-199) */
+	__le16	ctime;		/* Creation time */
+	__le16	cdate;		/* Creation date */
+	__le16	adate;		/* Last access date */
+	__le16	starthi;	/* High 16 bits of cluster in FAT32 */
+	__le16	time,date,start;/* time, date and first cluster */
+	__le32	size;		/* file size (in bytes) */
+};
+
+/* Up to 13 characters of the name */
+struct msdos_dir_slot {
+	__u8    id;		/* sequence number for slot */
+	__u8    name0_4[10];	/* first 5 characters in name */
+	__u8    attr;		/* attribute byte */
+	__u8    reserved;	/* always 0 */
+	__u8    alias_checksum;	/* checksum for 8.3 alias */
+	__u8    name5_10[12];	/* 6 more characters in name */
+	__le16   start;		/* starting cluster number, 0 in long slots */
+	__u8    name11_12[4];	/* last 2 characters in name */
+};
+
+#ifdef __KERNEL__
+/* media of boot sector */
+static inline int fat_valid_media(u8 media)
+{
+	return 0xf8 <= media || media == 0xf0;
+}
+#endif /* !__KERNEL__ */
+#endif /* !_LINUX_MSDOS_FS_H */