/* $OpenBSD: bpb.h,v 1.3 1998/01/11 20:39:03 provos Exp $ */ /* $NetBSD: bpb.h,v 1.6 1997/10/17 11:23:35 ws Exp $ */ /* * Written by Paul Popelka (paulp@uts.amdahl.com) * * You can do anything you want with this software, just don't say you wrote * it, and don't remove this notice. * * This software is provided "as is". * * The author supplies this software to be publicly redistributed on the * understanding that the author is not responsible for the correct * functioning of this software in any circumstances and is not liable for * any damages caused by this software. * * October 1992 */ /* * BIOS Parameter Block (BPB) for DOS 3.3 */ struct bpb33 { u_int16_t bpbBytesPerSec; /* bytes per sector */ u_int8_t bpbSecPerClust; /* sectors per cluster */ u_int16_t bpbResSectors; /* number of reserved sectors */ u_int8_t bpbFATs; /* number of FATs */ u_int16_t bpbRootDirEnts; /* number of root directory entries */ u_int16_t bpbSectors; /* total number of sectors */ u_int8_t bpbMedia; /* media descriptor */ u_int16_t bpbFATsecs; /* number of sectors per FAT */ u_int16_t bpbSecPerTrack; /* sectors per track */ u_int16_t bpbHeads; /* number of heads */ u_int16_t bpbHiddenSecs; /* number of hidden sectors */ }; /* * BPB for DOS 5.0 The difference is bpbHiddenSecs is a short for DOS 3.3, * and bpbHugeSectors is not in the 3.3 bpb. */ struct bpb50 { u_int16_t bpbBytesPerSec; /* bytes per sector */ u_int8_t bpbSecPerClust; /* sectors per cluster */ u_int16_t bpbResSectors; /* number of reserved sectors */ u_int8_t bpbFATs; /* number of FATs */ u_int16_t bpbRootDirEnts; /* number of root directory entries */ u_int16_t bpbSectors; /* total number of sectors */ u_int8_t bpbMedia; /* media descriptor */ u_int16_t bpbFATsecs; /* number of sectors per FAT */ u_int16_t bpbSecPerTrack; /* sectors per track */ u_int16_t bpbHeads; /* number of heads */ u_int32_t bpbHiddenSecs; /* # of hidden sectors */ u_int32_t bpbHugeSectors; /* # of sectors if bpbSectors == 0 */ }; /* * BPB for DOS 7.10 (FAT32). This one has a few extensions to bpb50. */ struct bpb710 { u_int16_t bpbBytesPerSec; /* bytes per sector */ u_int8_t bpbSecPerClust; /* sectors per cluster */ u_int16_t bpbResSectors; /* number of reserved sectors */ u_int8_t bpbFATs; /* number of FATs */ u_int16_t bpbRootDirEnts; /* number of root directory entries */ u_int16_t bpbSectors; /* total number of sectors */ u_int8_t bpbMedia; /* media descriptor */ u_int16_t bpbFATsecs; /* number of sectors per FAT */ u_int16_t bpbSecPerTrack; /* sectors per track */ u_int16_t bpbHeads; /* number of heads */ u_int32_t bpbHiddenSecs; /* # of hidden sectors */ u_int32_t bpbHugeSectors; /* # of sectors if bpbSectors == 0 */ u_int32_t bpbBigFATsecs; /* like bpbFATsecs for FAT32 */ u_int16_t bpbExtFlags; /* extended flags: */ #define FATNUM 0xf /* mask for numbering active FAT */ #define FATMIRROR 0x80 /* FAT is mirrored (like it always was) */ u_int16_t bpbFSVers; /* filesystem version */ #define FSVERS 0 /* currently only 0 is understood */ u_int32_t bpbRootClust; /* start cluster for root directory */ u_int16_t bpbFSInfo; /* filesystem info structure sector */ u_int16_t bpbBackup; /* backup boot sector */ /* There is a 12 byte filler here, but we ignore it */ }; #ifdef atari /* * BPB for gemdos filesystems. Atari leaves the obsolete stuff undefined. * Currently there is no need for a separate BPB structure. */ #if 0 struct bpb_a { u_int16_t bpbBytesPerSec; /* bytes per sector */ u_int8_t bpbSecPerClust; /* sectors per cluster */ u_int16_t bpbResSectors; /* number of reserved sectors */ u_int8_t bpbFATs; /* number of FATs */ u_int16_t bpbRootDirEnts; /* number of root directory entries */ u_int16_t bpbSectors; /* total number of sectors */ u_int8_t bpbUseless1; /* meaningless on gemdos fs */ u_int16_t bpbFATsecs; /* number of sectors per FAT */ u_int16_t bpbUseless2; /* meaningless for harddisk fs */ u_int16_t bpbUseless3; /* meaningless for harddisk fs */ u_int16_t bpbHiddenSecs; /* the TOS-BIOS ignores this */ }; #endif #endif /* atari */ /* * The following structures represent how the bpb's look on disk. shorts * and longs are just character arrays of the appropriate length. This is * because the compiler forces shorts and longs to align on word or * halfword boundaries. * * XXX The little-endian code here assumes that the processor can access * 16-bit and 32-bit quantities on byte boundaries. If this is not true, * use the macros for the big-endian case. */ #include <machine/endian.h> #if (BYTE_ORDER == LITTLE_ENDIAN) && defined(UNALIGNED_ACCESS) #define getushort(x) *((u_int16_t *)(x)) #define getulong(x) *((u_int32_t *)(x)) #define putushort(p, v) (*((u_int16_t *)(p)) = (v)) #define putulong(p, v) (*((u_int32_t *)(p)) = (v)) #else #define getushort(x) (((u_int8_t *)(x))[0] + (((u_int8_t *)(x))[1] << 8)) #define getulong(x) (((u_int8_t *)(x))[0] + (((u_int8_t *)(x))[1] << 8) \ + (((u_int8_t *)(x))[2] << 16) \ + (((u_int8_t *)(x))[3] << 24)) #define putushort(p, v) (((u_int8_t *)(p))[0] = (v), \ ((u_int8_t *)(p))[1] = (v) >> 8) #define putulong(p, v) (((u_int8_t *)(p))[0] = (v), \ ((u_int8_t *)(p))[1] = (v) >> 8, \ ((u_int8_t *)(p))[2] = (v) >> 16,\ ((u_int8_t *)(p))[3] = (v) >> 24) #endif /* * BIOS Parameter Block (BPB) for DOS 3.3 */ struct byte_bpb33 { int8_t bpbBytesPerSec[2]; /* bytes per sector */ int8_t bpbSecPerClust; /* sectors per cluster */ int8_t bpbResSectors[2]; /* number of reserved sectors */ int8_t bpbFATs; /* number of FATs */ int8_t bpbRootDirEnts[2]; /* number of root directory entries */ int8_t bpbSectors[2]; /* total number of sectors */ int8_t bpbMedia; /* media descriptor */ int8_t bpbFATsecs[2]; /* number of sectors per FAT */ int8_t bpbSecPerTrack[2]; /* sectors per track */ int8_t bpbHeads[2]; /* number of heads */ int8_t bpbHiddenSecs[2]; /* number of hidden sectors */ }; /* * BPB for DOS 5.0 The difference is bpbHiddenSecs is a short for DOS 3.3, * and bpbHugeSectors is not in the 3.3 bpb. */ struct byte_bpb50 { int8_t bpbBytesPerSec[2]; /* bytes per sector */ int8_t bpbSecPerClust; /* sectors per cluster */ int8_t bpbResSectors[2]; /* number of reserved sectors */ int8_t bpbFATs; /* number of FATs */ int8_t bpbRootDirEnts[2]; /* number of root directory entries */ int8_t bpbSectors[2]; /* total number of sectors */ int8_t bpbMedia; /* media descriptor */ int8_t bpbFATsecs[2]; /* number of sectors per FAT */ int8_t bpbSecPerTrack[2]; /* sectors per track */ int8_t bpbHeads[2]; /* number of heads */ int8_t bpbHiddenSecs[4]; /* number of hidden sectors */ int8_t bpbHugeSectors[4]; /* # of sectors if bpbSectors == 0 */ }; /* * BPB for DOS 7.10 (FAT32). This one has a few extensions to bpb50. */ struct byte_bpb710 { u_int8_t bpbBytesPerSec[2]; /* bytes per sector */ u_int8_t bpbSecPerClust; /* sectors per cluster */ u_int8_t bpbResSectors[2]; /* number of reserved sectors */ u_int8_t bpbFATs; /* number of FATs */ u_int8_t bpbRootDirEnts[2]; /* number of root directory entries */ u_int8_t bpbSectors[2]; /* total number of sectors */ u_int8_t bpbMedia; /* media descriptor */ u_int8_t bpbFATsecs[2]; /* number of sectors per FAT */ u_int8_t bpbSecPerTrack[2]; /* sectors per track */ u_int8_t bpbHeads[2]; /* number of heads */ u_int8_t bpbHiddenSecs[4]; /* # of hidden sectors */ u_int8_t bpbHugeSectors[4]; /* # of sectors if bpbSectors == 0 */ u_int8_t bpbBigFATsecs[4]; /* like bpbFATsecs for FAT32 */ u_int8_t bpbExtFlags[2]; /* extended flags: */ u_int8_t bpbFSVers[2]; /* filesystem version */ u_int8_t bpbRootClust[4]; /* start cluster for root directory */ u_int8_t bpbFSInfo[2]; /* filesystem info structure sector */ u_int8_t bpbBackup[2]; /* backup boot sector */ /* There is a 12 byte filler here, but we ignore it */ }; /* * FAT32 FSInfo block. */ struct fsinfo { u_int8_t fsisig1[4]; u_int8_t fsifill1[480]; u_int8_t fsisig2[4]; u_int8_t fsinfree[4]; u_int8_t fsinxtfree[4]; u_int8_t fsifill2[12]; u_int8_t fsisig3[4]; u_int8_t fsifill3[508]; u_int8_t fsisig4[4]; };