sys/vfs/msdosfs/bootsect.h

   1 /* $FreeBSD: src/sys/msdosfs/bootsect.h,v 1.7 1999/08/28 00:48:06 peter Exp $ */
   2 /* $DragonFly: src/sys/vfs/msdosfs/bootsect.h,v 1.3 2004/01/08 18:39:18 asmodai Exp $ */
   3 /*      $NetBSD: bootsect.h,v 1.9 1997/11/17 15:36:17 ws Exp $  */
   4
   5 /*
   6  * Written by Paul Popelka (paulp@uts.amdahl.com)
   7  *
   8  * You can do anything you want with this software, just don't say you wrote
   9  * it, and don't remove this notice.
  10  *
  11  * This software is provided "as is".
  12  *
  13  * The author supplies this software to be publicly redistributed on the
  14  * understanding that the author is not responsible for the correct
  15  * functioning of this software in any circumstances and is not liable for
  16  * any damages caused by this software.
  17  *
  18  * October 1992
  19  */
  20
  21 /*
  22  * Format of a boot sector.  This is the first sector on a DOS floppy disk
  23  * or the fist sector of a partition on a hard disk.  But, it is not the
  24  * first sector of a partitioned hard disk.
  25  */
  26 struct bootsector33 {
  27         u_int8_t        bsJump[3];              /* jump inst E9xxxx or EBxx90 */
  28         int8_t          bsOemName[8];           /* OEM name and version */
  29         int8_t          bsBPB[19];              /* BIOS parameter block */
  30         int8_t          bsDriveNumber;          /* drive number (0x80) */
  31         int8_t          bsBootCode[479];        /* pad so struct is 512b */
  32         u_int8_t        bsBootSectSig0;
  33         u_int8_t        bsBootSectSig1;
  34 #define BOOTSIG0        0x55
  35 #define BOOTSIG1        0xaa
  36 };
  37
  38 struct extboot {
  39         int8_t          exDriveNumber;          /* drive number (0x80) */
  40         int8_t          exReserved1;            /* reserved */
  41         int8_t          exBootSignature;        /* ext. boot signature (0x29) */
  42 #define EXBOOTSIG       0x29
  43         int8_t          exVolumeID[4];          /* volume ID number */
  44         int8_t          exVolumeLabel[11];      /* volume label */
  45         int8_t          exFileSysType[8];       /* fs type (FAT12 or FAT16) */
  46 };
  47
  48 struct bootsector50 {
  49         u_int8_t        bsJump[3];              /* jump inst E9xxxx or EBxx90 */
  50         int8_t          bsOemName[8];           /* OEM name and version */
  51         int8_t          bsBPB[25];              /* BIOS parameter block */
  52         int8_t          bsExt[26];              /* Bootsector Extension */
  53         int8_t          bsBootCode[448];        /* pad so structure is 512b */
  54         u_int8_t        bsBootSectSig0;
  55         u_int8_t        bsBootSectSig1;
  56 #define BOOTSIG0        0x55
  57 #define BOOTSIG1        0xaa
  58 };
  59
  60 struct bootsector710 {
  61         u_int8_t        bsJump[3];              /* jump inst E9xxxx or EBxx90 */
  62         int8_t          bsOEMName[8];           /* OEM name and version */
  63         int8_t          bsPBP[53];              /* BIOS parameter block */
  64         int8_t          bsExt[26];              /* Bootsector Extension */
  65         int8_t          bsBootCode[418];        /* pad so structure is 512b */
  66         u_int8_t        bsBootSectSig2;         /* 2 & 3 are only defined for FAT32? */
  67         u_int8_t        bsBootSectSig3;
  68         u_int8_t        bsBootSectSig0;
  69         u_int8_t        bsBootSectSig1;
  70 #define BOOTSIG0        0x55
  71 #define BOOTSIG1        0xaa
  72 #define BOOTSIG2        0
  73 #define BOOTSIG3        0
  74 };
  75 #ifdef  atari
  76 /*
  77  * The boot sector on a gemdos fs is a little bit different from the msdos fs
  78  * format. Currently there is no need to declare a separate structure, the
  79  * bootsector33 struct will do.
  80  */
  81 #if 0
  82 struct bootsec_atari {
  83         u_int8_t        bsBranch[2];            /* branch inst if auto-boot     */
  84         int8_t          bsFiller[6];            /* anything or nothing          */
  85         int8_t          bsSerial[3];            /* serial no. for mediachange   */
  86         int8_t          bsBPB[19];              /* BIOS parameter block         */
  87         int8_t          bsBootCode[482];        /* pad so struct is 512b        */
  88 };
  89 #endif
  90 #endif /* atari */
  91
  92 union bootsector {
  93         struct bootsector33 bs33;
  94         struct bootsector50 bs50;
  95         struct bootsector710 bs710;
  96 };
  97
  98 #if 0
  99 /*
 100  * Shorthand for fields in the bpb.
 101  */
 102 #define bsBytesPerSec   bsBPB.bpbBytesPerSec
 103 #define bsSectPerClust  bsBPB.bpbSectPerClust
 104 #define bsResSectors    bsBPB.bpbResSectors
 105 #define bsFATS          bsBPB.bpbFATS
 106 #define bsRootDirEnts   bsBPB.bpbRootDirEnts
 107 #define bsSectors       bsBPB.bpbSectors
 108 #define bsMedia         bsBPB.bpbMedia
 109 #define bsFATsecs       bsBPB.bpbFATsecs
 110 #define bsSectPerTrack  bsBPB.bpbSectPerTrack
 111 #define bsHeads         bsBPB.bpbHeads
 112 #define bsHiddenSecs    bsBPB.bpbHiddenSecs
 113 #define bsHugeSectors   bsBPB.bpbHugeSectors
 114 #endif