/* $NetBSD: bpb.h,v 1.7 1997/11/17 15:36:24 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 */ #ifndef _FS_MSDOSFS_BPB_H_ #define _FS_MSDOSFS_BPB_H_ /* * BIOS Parameter Block (BPB) for DOS 3.3 */ struct bpb33 { uint16_t bpbBytesPerSec; /* bytes per sector */ uint8_t bpbSecPerClust; /* sectors per cluster */ uint16_t bpbResSectors; /* number of reserved sectors */ uint8_t bpbFATs; /* number of FATs */ uint16_t bpbRootDirEnts; /* number of root directory entries */ uint16_t bpbSectors; /* total number of sectors */ uint8_t bpbMedia; /* media descriptor */ uint16_t bpbFATsecs; /* number of sectors per FAT */ uint16_t bpbSecPerTrack; /* sectors per track */ uint16_t bpbHeads; /* number of heads */ uint16_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 { uint16_t bpbBytesPerSec; /* bytes per sector */ uint8_t bpbSecPerClust; /* sectors per cluster */ uint16_t bpbResSectors; /* number of reserved sectors */ uint8_t bpbFATs; /* number of FATs */ uint16_t bpbRootDirEnts; /* number of root directory entries */ uint16_t bpbSectors; /* total number of sectors */ uint8_t bpbMedia; /* media descriptor */ uint16_t bpbFATsecs; /* number of sectors per FAT */ uint16_t bpbSecPerTrack; /* sectors per track */ uint16_t bpbHeads; /* number of heads */ uint32_t bpbHiddenSecs; /* # of hidden sectors */ uint32_t bpbHugeSectors; /* # of sectors if bpbSectors == 0 */ }; /* * BPB for DOS 7.10 (FAT32). This one has a few extensions to bpb50. */ struct bpb710 { uint16_t bpbBytesPerSec; /* bytes per sector */ uint8_t bpbSecPerClust; /* sectors per cluster */ uint16_t bpbResSectors; /* number of reserved sectors */ uint8_t bpbFATs; /* number of FATs */ uint16_t bpbRootDirEnts; /* number of root directory entries */ uint16_t bpbSectors; /* total number of sectors */ uint8_t bpbMedia; /* media descriptor */ uint16_t bpbFATsecs; /* number of sectors per FAT */ uint16_t bpbSecPerTrack; /* sectors per track */ uint16_t bpbHeads; /* number of heads */ uint32_t bpbHiddenSecs; /* # of hidden sectors */ uint32_t bpbHugeSectors; /* # of sectors if bpbSectors == 0 */ uint32_t bpbBigFATsecs; /* like bpbFATsecs for FAT32 */ uint16_t bpbExtFlags; /* extended flags: */ #define FATNUM 0xf /* mask for numbering active FAT */ #define FATMIRROR 0x80 /* FAT is mirrored (like it always was) */ uint16_t bpbFSVers; /* filesystem version */ #define FSVERS 0 /* currently only 0 is understood */ uint32_t bpbRootClust; /* start cluster for root directory */ uint16_t bpbFSInfo; /* filesystem info structure sector */ uint16_t bpbBackup; /* backup boot sector */ uint8_t bpbReserved[12]; /* reserved for future expansion */ }; /* * 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. */ #include <sys/endian.h> #define getushort(x) le16dec(x) #define getulong(x) le32dec(x) #define putushort(p, v) le16enc(p, v) #define putulong(p, v) le32enc(p, v) /* * 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 { uint8_t bpbBytesPerSec[2]; /* bytes per sector */ uint8_t bpbSecPerClust; /* sectors per cluster */ uint8_t bpbResSectors[2]; /* number of reserved sectors */ uint8_t bpbFATs; /* number of FATs */ uint8_t bpbRootDirEnts[2]; /* number of root directory entries */ uint8_t bpbSectors[2]; /* total number of sectors */ uint8_t bpbMedia; /* media descriptor */ uint8_t bpbFATsecs[2]; /* number of sectors per FAT */ uint8_t bpbSecPerTrack[2]; /* sectors per track */ uint8_t bpbHeads[2]; /* number of heads */ uint8_t bpbHiddenSecs[4]; /* # of hidden sectors */ uint8_t bpbHugeSectors[4]; /* # of sectors if bpbSectors == 0 */ uint8_t bpbBigFATsecs[4]; /* like bpbFATsecs for FAT32 */ uint8_t bpbExtFlags[2]; /* extended flags: */ uint8_t bpbFSVers[2]; /* filesystem version */ uint8_t bpbRootClust[4]; /* start cluster for root directory */ uint8_t bpbFSInfo[2]; /* filesystem info structure sector */ uint8_t bpbBackup[2]; /* backup boot sector */ uint8_t bpbReserved[12]; /* reserved for future expansion */ }; /* * FAT32 FSInfo block. */ struct fsinfo { uint8_t fsisig1[4]; uint8_t fsifill1[480]; uint8_t fsisig2[4]; uint8_t fsinfree[4]; uint8_t fsinxtfree[4]; uint8_t fsifill2[12]; uint8_t fsisig3[4]; }; #endif /* !_FS_MSDOSFS_BPB_H_ */
