/*      $NetBSD: disklbl.h,v 1.3 2005/12/11 12:17:00 christos Exp $     */

/*
* 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.
* 3. 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
*/

#ifndef DISKLABEL_H
#define DISKLABEL_H

#define DISKMAGIC       ((u_int32_t)0x82564557) /* The disk magic number */

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" */

       /*
        * d_packname contains the pack identifier and is returned when
        * the disklabel is read off the disk or in-core copy.
        * d_boot0 and d_boot1 are the (optional) names of the
        * primary (block 0) and secondary (block 1-15) bootstraps
        * as found in /usr/mdec.  These are returned when using
        * getdiskbyname(3) to retrieve the values from /etc/disktab.
        */
       union {
               char    un_d_packname[16];      /* pack identifier */
               struct {
                       char *un_d_boot0;       /* primary bootstrap name */
                       char *un_d_boot1;       /* secondary bootstrap name */
               } un_b;
       } d_un;
#define d_packname      d_un.un_d_packname
#define d_boot0         d_un.un_b.un_d_boot0
#define d_boot1         d_un.un_b.un_d_boot1

                       /* 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 */
               union {
                       u_int16_t cpg;  /* UFS: FS cylinders per group */
                       u_int16_t sgs;  /* LFS: FS segment shift */
               } __partition_u1;
#define p_cpg   __partition_u1.cpg
#define p_sgs   __partition_u1.sgs
       } d_partitions[MAXPARTITIONS];  /* actually may be more */
};

#endif /* DISKLABEL_H */