/*
* 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);
}
/*
* 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);
}
/*
* 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);
}
/*
* 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);
}
