root/sys/arch/atari/stand/tostools/libtos/disklbl.h
/*      $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 */