1 /* $NetBSD: disklbl.h,v 1.3 2005/12/11 12:17:00 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1987, 1988, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)disklabel.h 8.2 (Berkeley) 7/10/94 32 */ 33 34 #ifndef DISKLABEL_H 35 #define DISKLABEL_H 36 37 #define DISKMAGIC ((u_int32_t)0x82564557) /* The disk magic number */ 38 39 struct disklabel { 40 u_int32_t d_magic; /* the magic number */ 41 u_int16_t d_type; /* drive type */ 42 u_int16_t d_subtype; /* controller/d_type specific */ 43 char d_typename[16]; /* type name, e.g. "eagle" */ 44 45 /* 46 * d_packname contains the pack identifier and is returned when 47 * the disklabel is read off the disk or in-core copy. 48 * d_boot0 and d_boot1 are the (optional) names of the 49 * primary (block 0) and secondary (block 1-15) bootstraps 50 * as found in /usr/mdec. These are returned when using 51 * getdiskbyname(3) to retrieve the values from /etc/disktab. 52 */ 53 union { 54 char un_d_packname[16]; /* pack identifier */ 55 struct { 56 char *un_d_boot0; /* primary bootstrap name */ 57 char *un_d_boot1; /* secondary bootstrap name */ 58 } un_b; 59 } d_un; 60 #define d_packname d_un.un_d_packname 61 #define d_boot0 d_un.un_b.un_d_boot0 62 #define d_boot1 d_un.un_b.un_d_boot1 63 64 /* disk geometry: */ 65 u_int32_t d_secsize; /* # of bytes per sector */ 66 u_int32_t d_nsectors; /* # of data sectors per track */ 67 u_int32_t d_ntracks; /* # of tracks per cylinder */ 68 u_int32_t d_ncylinders; /* # of data cylinders per unit */ 69 u_int32_t d_secpercyl; /* # of data sectors per cylinder */ 70 u_int32_t d_secperunit; /* # of data sectors per unit */ 71 72 /* 73 * Spares (bad sector replacements) below are not counted in 74 * d_nsectors or d_secpercyl. Spare sectors are assumed to 75 * be physical sectors which occupy space at the end of each 76 * track and/or cylinder. 77 */ 78 u_int16_t d_sparespertrack; /* # of spare sectors per track */ 79 u_int16_t d_sparespercyl; /* # of spare sectors per cylinder */ 80 /* 81 * Alternate cylinders include maintenance, replacement, configuration 82 * description areas, etc. 83 */ 84 u_int32_t d_acylinders; /* # of alt. cylinders per unit */ 85 86 /* hardware characteristics: */ 87 /* 88 * d_interleave, d_trackskew and d_cylskew describe perturbations 89 * in the media format used to compensate for a slow controller. 90 * Interleave is physical sector interleave, set up by the 91 * formatter or controller when formatting. When interleaving is 92 * in use, logically adjacent sectors are not physically 93 * contiguous, but instead are separated by some number of 94 * sectors. It is specified as the ratio of physical sectors 95 * traversed per logical sector. Thus an interleave of 1:1 96 * implies contiguous layout, while 2:1 implies that logical 97 * sector 0 is separated by one sector from logical sector 1. 98 * d_trackskew is the offset of sector 0 on track N relative to 99 * sector 0 on track N-1 on the same cylinder. Finally, d_cylskew 100 * is the offset of sector 0 on cylinder N relative to sector 0 101 * on cylinder N-1. 102 */ 103 u_int16_t d_rpm; /* rotational speed */ 104 u_int16_t d_interleave; /* hardware sector interleave */ 105 u_int16_t d_trackskew; /* sector 0 skew, per track */ 106 u_int16_t d_cylskew; /* sector 0 skew, per cylinder */ 107 u_int32_t d_headswitch; /* head switch time, usec */ 108 u_int32_t d_trkseek; /* track-to-track seek, usec */ 109 u_int32_t d_flags; /* generic flags */ 110 #define NDDATA 5 111 u_int32_t d_drivedata[NDDATA]; /* drive-type specific information */ 112 #define NSPARE 5 113 u_int32_t d_spare[NSPARE]; /* reserved for future use */ 114 u_int32_t d_magic2; /* the magic number (again) */ 115 u_int16_t d_checksum; /* xor of data incl. partitions */ 116 117 /* filesystem and partition information: */ 118 u_int16_t d_npartitions; /* number of partitions in following */ 119 u_int32_t d_bbsize; /* size of boot area at sn0, bytes */ 120 u_int32_t d_sbsize; /* max size of fs superblock, bytes */ 121 struct partition { /* the partition table */ 122 u_int32_t p_size; /* number of sectors in partition */ 123 u_int32_t p_offset; /* starting sector */ 124 u_int32_t p_fsize; /* filesystem basic fragment size */ 125 u_int8_t p_fstype; /* filesystem type, see below */ 126 u_int8_t p_frag; /* filesystem fragments per block */ 127 union { 128 u_int16_t cpg; /* UFS: FS cylinders per group */ 129 u_int16_t sgs; /* LFS: FS segment shift */ 130 } __partition_u1; 131 #define p_cpg __partition_u1.cpg 132 #define p_sgs __partition_u1.sgs 133 } d_partitions[MAXPARTITIONS]; /* actually may be more */ 134 }; 135 136 #endif /* DISKLABEL_H */ 137