sys/sys/disklabel.h

/*-
 * Copyright (c) 1987, 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)disklabel.h	8.2 (Berkeley) 7/10/94
 * $FreeBSD: head/sys/sys/disklabel.h 139825 2005-01-07 02:29:27Z imp $
 */

#ifndef _SYS_DISKLABEL_H_
#define	_SYS_DISKLABEL_H_

#ifndef _KERNEL
#include <sys/types.h>
#endif
#include <sys/ioccom.h>

/*
 * Disk description table, see disktab(5)
 */
#define	_PATH_DISKTAB	"/etc/disktab"

/*
 * Each disk has a label which includes information about the hardware
 * disk geometry, filesystem partitions, and drive specific information.
 * The label is in block 0 or 1, possibly offset from the beginning
 * to leave room for a bootstrap, etc.
 */

/* XXX these should be defined per controller (or drive) elsewhere, not here! */
#if defined(__i386__) || defined(__amd64__) || defined(__ia64__)
#define LABELSECTOR	1			/* sector containing label */
#define LABELOFFSET	0			/* offset of label in sector */
#endif

#ifdef __alpha__
#define LABELSECTOR	0
#define LABELOFFSET	64
#endif

#define DISKMAGIC	((u_int32_t)0x82564557)	/* The disk magic number */
#ifndef MAXPARTITIONS
#define	MAXPARTITIONS	8
#endif

/* Size of bootblock area in sector-size neutral bytes */
#define BBSIZE		8192

#define	LABEL_PART	2		/* partition containing label */
#define	RAW_PART	2		/* partition containing whole disk */
#define	SWAP_PART	1		/* partition normally containing swap */

struct disklabel {
	u_int32_t d_magic;		/* the magic number */
	u_int16_t d_type;		/* drive type */
	u_int16_t d_subtype;		/* controller/d_type specific */
	char	  d_typename[16];	/* type name, e.g. "eagle" */

	char      d_packname[16];	/* pack identifier */

			/* disk geometry: */
	u_int32_t d_secsize;		/* # of bytes per sector */
	u_int32_t d_nsectors;		/* # of data sectors per track */
	u_int32_t d_ntracks;		/* # of tracks per cylinder */
	u_int32_t d_ncylinders;		/* # of data cylinders per unit */
	u_int32_t d_secpercyl;		/* # of data sectors per cylinder */
	u_int32_t d_secperunit;		/* # of data sectors per unit */

	/*
	 * Spares (bad sector replacements) below are not counted in
	 * d_nsectors or d_secpercyl.  Spare sectors are assumed to
	 * be physical sectors which occupy space at the end of each
	 * track and/or cylinder.
	 */
	u_int16_t d_sparespertrack;	/* # of spare sectors per track */
	u_int16_t d_sparespercyl;	/* # of spare sectors per cylinder */
	/*
	 * Alternate cylinders include maintenance, replacement, configuration
	 * description areas, etc.
	 */
	u_int32_t d_acylinders;		/* # of alt. cylinders per unit */

			/* hardware characteristics: */
	/*
	 * d_interleave, d_trackskew and d_cylskew describe perturbations
	 * in the media format used to compensate for a slow controller.
	 * Interleave is physical sector interleave, set up by the
	 * formatter or controller when formatting.  When interleaving is
	 * in use, logically adjacent sectors are not physically
	 * contiguous, but instead are separated by some number of
	 * sectors.  It is specified as the ratio of physical sectors
	 * traversed per logical sector.  Thus an interleave of 1:1
	 * implies contiguous layout, while 2:1 implies that logical
	 * sector 0 is separated by one sector from logical sector 1.
	 * d_trackskew is the offset of sector 0 on track N relative to
	 * sector 0 on track N-1 on the same cylinder.  Finally, d_cylskew
	 * is the offset of sector 0 on cylinder N relative to sector 0
	 * on cylinder N-1.
	 */
	u_int16_t d_rpm;		/* rotational speed */
	u_int16_t d_interleave;		/* hardware sector interleave */
	u_int16_t d_trackskew;		/* sector 0 skew, per track */
	u_int16_t d_cylskew;		/* sector 0 skew, per cylinder */
	u_int32_t d_headswitch;		/* head switch time, usec */
	u_int32_t d_trkseek;		/* track-to-track seek, usec */
	u_int32_t d_flags;		/* generic flags */
#define NDDATA 5
	u_int32_t d_drivedata[NDDATA];	/* drive-type specific information */
#define NSPARE 5
	u_int32_t d_spare[NSPARE];	/* reserved for future use */
	u_int32_t d_magic2;		/* the magic number (again) */
	u_int16_t d_checksum;		/* xor of data incl. partitions */

			/* filesystem and partition information: */
	u_int16_t d_npartitions;	/* number of partitions in following */
	u_int32_t d_bbsize;		/* size of boot area at sn0, bytes */
	u_int32_t d_sbsize;		/* max size of fs superblock, bytes */
	struct partition {		/* the partition table */
		u_int32_t p_size;	/* number of sectors in partition */
		u_int32_t p_offset;	/* starting sector */
		u_int32_t p_fsize;	/* filesystem basic fragment size */
		u_int8_t p_fstype;	/* filesystem type, see below */
		u_int8_t p_frag;	/* filesystem fragments per block */
		u_int16_t p_cpg;	/* filesystem cylinders per group */
	} d_partitions[MAXPARTITIONS];	/* actually may be more */
};

#ifdef CTASSERT
CTASSERT(sizeof(struct disklabel) == 148 + MAXPARTITIONS * 16);
#endif

static __inline u_int16_t dkcksum(struct disklabel *lp);
static __inline u_int16_t
dkcksum(struct disklabel *lp)
{
	u_int16_t *start, *end;
	u_int16_t sum = 0;

	start = (u_int16_t *)lp;
	end = (u_int16_t *)&lp->d_partitions[lp->d_npartitions];
	while (start < end)
		sum ^= *start++;
	return (sum);
}


/* d_type values: */
#define	DTYPE_SMD		1		/* SMD, XSMD; VAX hp/up */
#define	DTYPE_MSCP		2		/* MSCP */
#define	DTYPE_DEC		3		/* other DEC (rk, rl) */
#define	DTYPE_SCSI		4		/* SCSI */
#define	DTYPE_ESDI		5		/* ESDI interface */
#define	DTYPE_ST506		6		/* ST506 etc. */
#define	DTYPE_HPIB		7		/* CS/80 on HP-IB */
#define	DTYPE_HPFL		8		/* HP Fiber-link */
#define	DTYPE_FLOPPY		10		/* floppy */
#define	DTYPE_CCD		11		/* concatenated disk */
#define	DTYPE_VINUM		12		/* vinum volume */
#define	DTYPE_DOC2K		13		/* Msys DiskOnChip */
#define	DTYPE_RAID		14		/* CMU RAIDFrame */
#define	DTYPE_JFS2		16		/* IBM JFS 2 */

#ifdef DKTYPENAMES
static const char *dktypenames[] = {
	"unknown",
	"SMD",
	"MSCP",
	"old DEC",
	"SCSI",
	"ESDI",
	"ST506",
	"HP-IB",
	"HP-FL",
	"type 9",
	"floppy",
	"CCD",
	"Vinum",
	"DOC2K",
	"Raid",
	"?",
	"jfs",
	NULL
};
#define DKMAXTYPES	(sizeof(dktypenames) / sizeof(dktypenames[0]) - 1)
#endif

/*
 * Filesystem type and version.
 * Used to interpret other filesystem-specific
 * per-partition information.
 */
#define	FS_UNUSED	0		/* unused */
#define	FS_SWAP		1		/* swap */
#define	FS_V6		2		/* Sixth Edition */
#define	FS_V7		3		/* Seventh Edition */
#define	FS_SYSV		4		/* System V */
#define	FS_V71K		5		/* V7 with 1K blocks (4.1, 2.9) */
#define	FS_V8		6		/* Eighth Edition, 4K blocks */
#define	FS_BSDFFS	7		/* 4.2BSD fast filesystem */
#define	FS_MSDOS	8		/* MSDOS filesystem */
#define	FS_BSDLFS	9		/* 4.4BSD log-structured filesystem */
#define	FS_OTHER	10		/* in use, but unknown/unsupported */
#define	FS_HPFS		11		/* OS/2 high-performance filesystem */
#define	FS_ISO9660	12		/* ISO 9660, normally CD-ROM */
#define	FS_BOOT		13		/* partition contains bootstrap */
#define	FS_VINUM	14		/* Vinum drive */
#define	FS_RAID		15		/* RAIDFrame drive */
#define	FS_JFS2		21		/* IBM JFS2 */

#ifdef	FSTYPENAMES
static const char *fstypenames[] = {
	"unused",
	"swap",
	"Version 6",
	"Version 7",
	"System V",
	"4.1BSD",
	"Eighth Edition",
	"4.2BSD",
	"MSDOS",
	"4.4LFS",
	"unknown",
	"HPFS",
	"ISO9660",
	"boot",
	"vinum",
	"raid",
	"?",
	"?",
	"?",
	"?",
	"jfs",
	NULL
};
#define FSMAXTYPES	(sizeof(fstypenames) / sizeof(fstypenames[0]) - 1)
#endif

/*
 * flags shared by various drives:
 */
#define	D_REMOVABLE	0x01		/* removable media */
#define	D_ECC		0x02		/* supports ECC */
#define	D_BADSECT	0x04		/* supports bad sector forw. */
#define	D_RAMDISK	0x08		/* disk emulator */
#define	D_CHAIN		0x10		/* can do back-back transfers */

/*
 * Disklabel-specific ioctls.
 *
 * NB: <sys/disk.h> defines ioctls from 'd'/128 and up.
 */
		/* get and set disklabel */
#define DIOCGDINFO	_IOR('d', 101, struct disklabel)/* get */
#define DIOCSDINFO	_IOW('d', 102, struct disklabel)/* set */
#define DIOCWDINFO	_IOW('d', 103, struct disklabel)/* set, update disk */
#define DIOCBSDBB	_IOW('d', 110, void *)	/* write bootblocks */

/*
 * Functions for proper encoding/decoding of struct disklabel into/from
 * bytestring.
 */
void bsd_partition_le_dec(u_char *ptr, struct partition *d);
int bsd_disklabel_le_dec(u_char *ptr, struct disklabel *d, int maxpart);
void bsd_partition_le_enc(u_char *ptr, struct partition *d);
void bsd_disklabel_le_enc(u_char *ptr, struct disklabel *d);

#ifndef _KERNEL
__BEGIN_DECLS
struct disklabel *getdiskbyname(const char *);
__END_DECLS
#endif

#endif /* !_SYS_DISKLABEL_H_ */