示例#1
0
文件: disksubr.c 项目: MarginC/kame
/*
 * Attempt to read a disk label from a device
 * using the indicated strategy routine.
 * The label must be partly set up before this:
 * secpercyl, secsize and anything required for a block i/o read
 * operation in the driver's strategy/start routines
 * must be filled in before calling us.
 *
 * If dos partition table requested, attempt to load it and
 * find disklabel inside a DOS partition. Also, if bad block
 * table needed, attempt to extract it as well. Return buffer
 * for use in signalling errors if requested.
 *
 * Returns null on success and an error string on failure.
 */
char *
readdisklabel(dev_t dev, void (*strat)(struct buf *), struct disklabel *lp,
    struct cpu_disklabel *osdep)
{
	struct mbr_partition *dp;
	struct partition *pp;
	struct dkbad *bdp;
	struct buf *bp;
	struct disklabel *dlp;
	char *msg = NULL;
	int dospartoff, cyl, i;

	/* minimal requirements for archtypal disk label */
	if (lp->d_secsize == 0)
		lp->d_secsize = DEV_BSIZE;
	if (lp->d_secperunit == 0)
		lp->d_secperunit = 0x1fffffff;
#if 0
	if (lp->d_ncylinders == 16383) {
		printf("disklabel: Disk > 8G ... readjusting chs %d/%d/%d to ",
			lp->d_ncylinders, lp->d_ntracks, lp->d_nsectors);
		lp->d_ncylinders = lp->d_secperunit /  lp->d_ntracks / lp->d_nsectors;
		printf("%d/%d/%d\n",
			lp->d_ncylinders, lp->d_ntracks, lp->d_nsectors);
	}
#endif
	lp->d_npartitions = RAW_PART + 1;
	for (i = 0; i < RAW_PART; i++) {
		lp->d_partitions[i].p_size = 0;
		lp->d_partitions[i].p_offset = 0;
	}
	if (lp->d_partitions[i].p_size == 0)
		lp->d_partitions[i].p_size = 0x1fffffff;
	lp->d_partitions[i].p_offset = 0;

	/* get a buffer and initialize it */
	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = dev;

	/* do dos partitions in the process of getting disklabel? */
	dospartoff = 0;
	cyl = LABELSECTOR / lp->d_secpercyl;
	if (!osdep)
		goto nombrpart;
	dp = osdep->dosparts;

	/* read master boot record */
	bp->b_blkno = MBR_BBSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags |= B_READ;
	bp->b_cylinder = MBR_BBSECTOR / lp->d_secpercyl;
	(*strat)(bp);

	/* if successful, wander through dos partition table */
	if (biowait(bp)) {
		msg = "dos partition I/O error";
		goto done;
	} else {
		struct mbr_partition *ourdp = NULL;

		ourdp = mbr_findslice(dp, bp);
		if (ourdp ==  NO_MBR_SIGNATURE)
			goto nombrpart;

		for (i = 0; i < NMBRPART; i++, dp++) {
			/* Install in partition e, f, g, or h. */
			pp = &lp->d_partitions[RAW_PART + 1 + i];
			pp->p_offset = dp->mbrp_start;
			pp->p_size = dp->mbrp_size;
			if (dp->mbrp_typ == MBR_PTYPE_LNXEXT2)
				pp->p_fstype = FS_EX2FS;

			if (dp->mbrp_typ == MBR_PTYPE_LNXSWAP)
				pp->p_fstype = FS_SWAP;

			/* is this ours? */
			if (dp == ourdp) {
				/* need sector address for SCSI/IDE,
				 cylinder for ESDI/ST506/RLL */
				dospartoff = dp->mbrp_start;
				cyl = MBR_PCYL(dp->mbrp_scyl, dp->mbrp_ssect);

				/* update disklabel with details */
				lp->d_partitions[2].p_size =
				    dp->mbrp_size;
				lp->d_partitions[2].p_offset = 
				    dp->mbrp_start;
			}
		}
		lp->d_npartitions = RAW_PART + 1 + i;
	}

nombrpart:
	/* next, dig out disk label */
	bp->b_blkno = dospartoff + LABELSECTOR;
	bp->b_cylinder = cyl;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags &= ~(B_DONE);
	bp->b_flags |= B_READ;
	(*strat)(bp);

	/* if successful, locate disk label within block and validate */
	if (biowait(bp)) {
		msg = "disk label I/O error";
		goto done;
	}
	for (dlp = (struct disklabel *)bp->b_data;
	    dlp <= (struct disklabel *)(bp->b_data + lp->d_secsize - sizeof(*dlp));
	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
		if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC) {
			if (msg == NULL)
				msg = "no disk label";
		} else if (dlp->d_npartitions > MAXPARTITIONS ||
			   dkcksum(dlp) != 0)
			msg = "disk label corrupted";
		else {
			*lp = *dlp;
			msg = NULL;
			break;
		}
	}

	if (msg)
		goto done;

	/* obtain bad sector table if requested and present */
	if (osdep && (lp->d_flags & D_BADSECT)) {
		struct dkbad *db;

		bdp = &osdep->bad;
		i = 0;
		do {
			/* read a bad sector table */
			bp->b_flags &= ~(B_DONE);
			bp->b_flags |= B_READ;
			bp->b_blkno = lp->d_secperunit - lp->d_nsectors + i;
			if (lp->d_secsize > DEV_BSIZE)
				bp->b_blkno *= lp->d_secsize / DEV_BSIZE;
			else
				bp->b_blkno /= DEV_BSIZE / lp->d_secsize;
			bp->b_bcount = lp->d_secsize;
			bp->b_cylinder = lp->d_ncylinders - 1;
			(*strat)(bp);

			/* if successful, validate, otherwise try another */
			if (biowait(bp)) {
				msg = "bad sector table I/O error";
			} else {
				db = (struct dkbad *)(bp->b_data);
#define DKBAD_MAGIC 0x4321
				if (db->bt_mbz == 0
					&& db->bt_flag == DKBAD_MAGIC) {
					msg = NULL;
					*bdp = *db;
					break;
				} else
					msg = "bad sector table corrupted";
			}
		} while ((bp->b_flags & B_ERROR) && (i += 2) < 10 &&
			i < lp->d_nsectors);
	}

done:
	brelse(bp);
	return (msg);
}
示例#2
0
文件: disksubr.c 项目: ryo/netbsd-src
/*
 * Write disk label back to device after modification.
 */
int
writedisklabel(dev_t dev, void (*strat)(struct buf *), struct disklabel *lp,
    struct cpu_disklabel *osdep)
{
	struct mbr_partition *dp;
	struct buf *bp;
	struct disklabel *dlp;
	int error, dospartoff, cyl;

	/* get a buffer and initialize it */
	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = dev;

	/* do dos partitions in the process of getting disklabel? */
	dospartoff = 0;
	cyl = LABELSECTOR / lp->d_secpercyl;
	if (!osdep)
		goto nombrpart;
	dp = osdep->mbrparts;

	/* read master boot record */
	bp->b_blkno = MBR_BBSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags |= B_READ;
	bp->b_cylinder = MBR_BBSECTOR / lp->d_secpercyl;
	(*strat)(bp);

	if ((error = biowait(bp)) == 0) {
		struct mbr_partition *ourdp = NULL;

		ourdp = mbr_findslice(dp, bp);
		if (ourdp ==  NO_MBR_SIGNATURE)
			goto nombrpart;

		if (ourdp) {
			/* need sector address for SCSI/IDE,
			   cylinder for ESDI/ST506/RLL */
			dospartoff = le32toh(ourdp->mbrp_start);
			cyl = MBR_PCYL(ourdp->mbrp_scyl, ourdp->mbrp_ssect);
		}
	}

 nombrpart:
#ifdef maybe
	/* disklabel in appropriate location? */
	if (lp->d_partitions[2].p_offset != 0
	    && lp->d_partitions[2].p_offset != dospartoff) {
		error = EXDEV;
		goto done;
	}
#endif

	/* next, dig out disk label */
	bp->b_blkno = dospartoff + LABELSECTOR;
	bp->b_cylinder = cyl;
	bp->b_bcount = lp->d_secsize;
	bp->b_oflags &= ~(BO_DONE);
	bp->b_flags |= B_READ;
	(*strat)(bp);

	/* if successful, locate disk label within block and validate */
	if ((error = biowait(bp)) != 0)
		goto done;
	for (dlp = (struct disklabel *)bp->b_data;
	    dlp <= (struct disklabel *)((char *)bp->b_data + lp->d_secsize -
		sizeof(*dlp));
	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC &&
		    dlp->d_npartitions <= MAXPARTITIONS &&
		    dkcksum(dlp) == 0) {
			/* found disklabel in host's endian */
			*dlp = *lp;
			goto found;
#ifdef BSDDISKLABEL_EI
		} else if (bswap32(dlp->d_magic) == DISKMAGIC &&
		    bswap32(dlp->d_magic2) == DISKMAGIC &&
		    bswap16(dlp->d_npartitions) <= MAXPARTITIONS &&
		    dkcksum_re(dlp) == 0) {
			/* found disklabel in the opposite endian */
			swap_endian_disklabel(dlp, lp);
			/* recalculate cksum in reversed endian */
			dlp->d_checksum = 0;
			dlp->d_checksum = dkcksum_re(dlp);
			goto found;
#endif
#ifdef COMPAT_MMEYE_OLDLABEL
		} else if (le32toh(dlp->d_magic) == DISKMAGIC &&
		    le32toh(dlp->d_magic2) == DISKMAGIC &&
		    le16toh(dlp->d_npartitions) <= MAXPARTITIONS &&
		    dkcksum_mmeye(dlp) == 0) {
			/* found disklabel by old mmeye's rule */
			swap_mmeye_disklabel(dlp, lp);
			/* recalculate cksum for it */
			dlp->d_checksum = 0;
			dlp->d_checksum = dkcksum_mmeye(dlp);
			goto found;
#endif
		}
	}
	/* No valid disklabel found on disk */
	error = ESRCH;
	goto done;

 found:
	bp->b_oflags &= ~(BO_DONE);
	bp->b_flags &= ~(B_READ);
	bp->b_flags |= B_WRITE;
	(*strat)(bp);
	error = biowait(bp);

 done:
	brelse(bp, 0);
	return (error);
}
示例#3
0
文件: disksubr.c 项目: MarginC/kame
/*
 * Write disk label back to device after modification.
 */
int
writedisklabel(dev_t dev, void (*strat)(struct buf *), struct disklabel *lp,
    struct cpu_disklabel *osdep)
{
	struct mbr_partition *dp;
	struct buf *bp;
	struct disklabel *dlp;
	int error, dospartoff, cyl;

	/* get a buffer and initialize it */
	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = dev;

	/* do dos partitions in the process of getting disklabel? */
	dospartoff = 0;
	cyl = LABELSECTOR / lp->d_secpercyl;
	if (!osdep)
		goto nombrpart;
	dp = osdep->dosparts;

	/* read master boot record */
	bp->b_blkno = MBR_BBSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags |= B_READ;
	bp->b_cylinder = MBR_BBSECTOR / lp->d_secpercyl;
	(*strat)(bp);

	if ((error = biowait(bp)) == 0) {
		struct mbr_partition *ourdp = NULL;

		ourdp = mbr_findslice(dp, bp);
		if (ourdp ==  NO_MBR_SIGNATURE)
			goto nombrpart;

		if (ourdp) {
			/* need sector address for SCSI/IDE,
			 cylinder for ESDI/ST506/RLL */
			dospartoff = ourdp->mbrp_start;
			cyl = MBR_PCYL(ourdp->mbrp_scyl, ourdp->mbrp_ssect);
		}
	}

nombrpart:
	/* next, dig out disk label */
	bp->b_blkno = dospartoff + LABELSECTOR;
	bp->b_cylinder = cyl;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags &= ~(B_DONE);
	bp->b_flags |= B_READ;
	(*strat)(bp);

	/* if successful, locate disk label within block and validate */
	if ((error = biowait(bp)) != 0)
		goto done;
	for (dlp = (struct disklabel *)bp->b_data;
	    dlp <= (struct disklabel *)(bp->b_data + lp->d_secsize - sizeof(*dlp));
	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC &&
		    dkcksum(dlp) == 0) {
			*dlp = *lp;
			bp->b_flags &= ~(B_READ|B_DONE);
			bp->b_flags |= B_WRITE;
			(*strat)(bp);
			error = biowait(bp);
			goto done;
		}
	}
	error = ESRCH;

done:
	brelse(bp);
	return (error);
}
示例#4
0
文件: disksubr.c 项目: ryo/netbsd-src
/*
 * Attempt to read a disk label from a device
 * using the indicated strategy routine.
 * The label must be partly set up before this:
 * secpercyl, secsize and anything required for a block i/o read
 * operation in the driver's strategy/start routines
 * must be filled in before calling us.
 *
 * If dos partition table requested, attempt to load it and
 * find disklabel inside a DOS partition. Also, if bad block
 * table needed, attempt to extract it as well. Return buffer
 * for use in signalling errors if requested.
 *
 * Returns null on success and an error string on failure.
 */
const char *
readdisklabel(dev_t dev, void (*strat)(struct buf *), struct disklabel *lp,
    struct cpu_disklabel *osdep)
{
	struct mbr_partition *dp;
	struct partition *pp;
	struct dkbad *bdp;
	struct buf *bp;
	struct disklabel *dlp;
	const char *msg = NULL;
	int dospartoff, cyl, i, *ip;

	/* minimal requirements for archtypal disk label */
	if (lp->d_secsize == 0)
		lp->d_secsize = DEV_BSIZE;
	if (lp->d_secperunit == 0)
		lp->d_secperunit = 0x1fffffff;
#if 0
	if (lp->d_ncylinders == 16383) {
		printf("disklabel: Disk > 8G ... readjusting chs %d/%d/%d to ",
		    lp->d_ncylinders, lp->d_ntracks, lp->d_nsectors);
		lp->d_ncylinders = lp->d_secperunit /  lp->d_ntracks / lp->d_nsectors;
		printf("%d/%d/%d\n",
		    lp->d_ncylinders, lp->d_ntracks, lp->d_nsectors);
	}
#endif
	lp->d_npartitions = RAW_PART + 1;
	for (i = 0; i < RAW_PART; i++) {
		lp->d_partitions[i].p_size = 0;
		lp->d_partitions[i].p_offset = 0;
	}
	if (lp->d_partitions[i].p_size == 0)
		lp->d_partitions[i].p_size = 0x1fffffff;
	lp->d_partitions[i].p_offset = 0;

	/* get a buffer and initialize it */
	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = dev;

	/* do dos partitions in the process of getting disklabel? */
	dospartoff = 0;
	cyl = LABELSECTOR / lp->d_secpercyl;
	if (!osdep)
		goto nombrpart;
	dp = osdep->mbrparts;

	/* read master boot record */
	bp->b_blkno = MBR_BBSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags |= B_READ;
	bp->b_cylinder = MBR_BBSECTOR / lp->d_secpercyl;
	(*strat)(bp);

	/* if successful, wander through dos partition table */
	if (biowait(bp)) {
		msg = "dos partition I/O error";
		goto done;
	} else {
		struct mbr_partition *ourdp = NULL;

		ourdp = mbr_findslice(dp, bp);
		if (ourdp == NO_MBR_SIGNATURE)
			goto nombrpart;

		for (i = 0; i < MBR_PART_COUNT; i++, dp++) {
			/* Install in partition e, f, g, or h. */
			pp = &lp->d_partitions[RAW_PART + 1 + i];
			pp->p_offset = le32toh(dp->mbrp_start);
			pp->p_size = le32toh(dp->mbrp_size);
			for (ip = fat_types; *ip != -1; ip++) {
				if (dp->mbrp_type == *ip)
					pp->p_fstype = FS_MSDOS;
			}
			if (dp->mbrp_type == MBR_PTYPE_LNXEXT2)
				pp->p_fstype = FS_EX2FS;

			if (dp->mbrp_type == MBR_PTYPE_NTFS)
				pp->p_fstype = FS_NTFS;

			/* is this ours? */
			if (dp == ourdp) {
				/* need sector address for SCSI/IDE,
				   cylinder for ESDI/ST506/RLL */
				dospartoff = le32toh(dp->mbrp_start);
				cyl = MBR_PCYL(dp->mbrp_scyl, dp->mbrp_ssect);

				/* update disklabel with details */
				lp->d_partitions[2].p_size =
				    le32toh(dp->mbrp_size);
				lp->d_partitions[2].p_offset =
				    le32toh(dp->mbrp_start);
#if 0
				if (lp->d_ntracks != dp->mbrp_ehd + 1 ||
				    lp->d_nsectors != MBR_PSECT(dp->mbrp_esect)) {
					printf("disklabel: BIOS sees chs %d/%d/%d as ",
					    lp->d_ncylinders, lp->d_ntracks,
					    lp->d_nsectors);
					lp->d_ntracks = dp->mbrp_ehd + 1;
					lp->d_nsectors = MBR_PSECT(dp->mbrp_esect);
					lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors;
					lp->d_ncylinders = lp->d_secperunit / lp->d_secpercyl;
					if (! lp->d_ncylinders)
						lp->d_ncylinders = 1;
					printf("%d/%d/%d\n",
					    lp->d_ncylinders, lp->d_ntracks,
					    lp->d_nsectors);
				}
#endif
			}
		}
		lp->d_npartitions = RAW_PART + 1 + i;
	}

 nombrpart:
	/* next, dig out disk label */
	bp->b_blkno = dospartoff + LABELSECTOR;
	bp->b_cylinder = cyl;
	bp->b_bcount = lp->d_secsize;
	bp->b_oflags &= ~(BO_DONE);
	bp->b_flags |= B_READ;
	(*strat)(bp);

	/* if successful, locate disk label within block and validate */
	if (biowait(bp)) {
		msg = "disk label I/O error";
		goto done;
	}
	for (dlp = (struct disklabel *)bp->b_data;
	    dlp <= (struct disklabel *)((char *)bp->b_data + lp->d_secsize -
		sizeof(*dlp));
	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC) {
			/* disklabel is written in host's endian */
			if (dlp->d_npartitions > MAXPARTITIONS ||
			    dkcksum(dlp) != 0)
				msg = "disk label corruptted";
			else {
				*lp = *dlp;
				msg = NULL;
				break;
			}
		}
#ifdef BSDDISKLABEL_EI
		if (bswap32(dlp->d_magic) == DISKMAGIC &&
		    bswap32(dlp->d_magic2) == DISKMAGIC) {
			/* disklabel is written in reversed endian */
			if (bswap16(dlp->d_npartitions) > MAXPARTITIONS ||
			    dkcksum_re(dlp) != 0)
				msg = "disk label corruptted";
			else {
				swap_endian_disklabel(lp, dlp);
				/* recalculate cksum in host's endian */
				lp->d_checksum = 0;
				lp->d_checksum = dkcksum(lp);

				msg = NULL;
				break;
			}
		}
#endif
#ifdef COMPAT_MMEYE_OLDLABEL
		if (le32toh(dlp->d_magic) == DISKMAGIC &&
		    le32toh(dlp->d_magic2) == DISKMAGIC) {
			if (le16toh(dlp->d_npartitions) > MAXPARTITIONS ||
			    dkcksum_mmeye(dlp) != 0)
				msg = "disk label corruptted";
			else {
				/* disklabel is written in old mmeye's way */
				swap_mmeye_disklabel(lp, dlp);
				/* recalculate cksum in host's endian */
				lp->d_checksum = 0;
				lp->d_checksum = dkcksum(lp);

				msg = NULL;
				break;
			}
		}
#endif
		if (msg == NULL)
			msg = "no disk label";
	}

	if (msg)
		goto done;

	/* obtain bad sector table if requested and present */
	if (osdep && (lp->d_flags & D_BADSECT)) {
		struct dkbad *db;

		bdp = &osdep->bad;
		i = 0;
		do {
			/* read a bad sector table */
			bp->b_oflags &= ~(BO_DONE);
			bp->b_flags |= B_READ;
			bp->b_blkno = lp->d_secperunit - lp->d_nsectors + i;
			if (lp->d_secsize > DEV_BSIZE)
				bp->b_blkno *= lp->d_secsize / DEV_BSIZE;
			else
				bp->b_blkno /= DEV_BSIZE / lp->d_secsize;
			bp->b_bcount = lp->d_secsize;
			bp->b_cylinder = lp->d_ncylinders - 1;
			(*strat)(bp);

			/* if successful, validate, otherwise try another */
			if (biowait(bp)) {
				msg = "bad sector table I/O error";
			} else {
				db = (struct dkbad *)(bp->b_data);
#define	DKBAD_MAGIC 0x4321
				if (db->bt_mbz == 0
				    && db->bt_flag == DKBAD_MAGIC) {
					msg = NULL;
					*bdp = *db;
					break;
				} else
					msg = "bad sector table corrupted";
			}
		} while (bp->b_error != 0 && (i += 2) < 10 &&
		    i < lp->d_nsectors);
	}

 done:
	brelse(bp, 0);
	return (msg);
}