subr_diskslice.c implements everything related to slices and labels except

reading and writing the slice tables and labels. subr_dkbad.c implements everything related to bad sector remapping using the bad144 format.
svn path=/head/; revision=5059
2024-12-13 10:02:38 +00:00 · 1994-12-12 00:20:34 +00:00 · 1994-12-12 00:20:34 +00:00 · d1f35d579f · 2020-12-20 02:59:44 +00:00
commit d1f35d579f
parent e82f07e12e
2 changed files with 680 additions and 0 deletions
--- a/sys/kern/subr_diskslice.c
+++ b/sys/kern/subr_diskslice.c
@ -0,0 +1,522 @@
+/*-
+ * Copyright (c) 1994 Bruce D. Evans.
+ * All rights reserved.
+ *
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * William Jolitz.
+ *
+ * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	from: @(#)wd.c	7.2 (Berkeley) 5/9/91
+ *	from: wd.c,v 1.55 1994/10/22 01:57:12 phk Exp $
+ *	from: @(#)ufs_disksubr.c	7.16 (Berkeley) 5/4/91
+ *	from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $
+ *	$Id:
+ */
+
+#include <sys/param.h>
+#include <sys/buf.h>
+#include <sys/disklabel.h>
+#include <sys/diskslice.h>
+#include <sys/dkbad.h>
+#include <sys/fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/malloc.h>
+#include <sys/stat.h>
+#include <sys/syslog.h>
+#include <sys/systm.h>
+
+#define b_cylinder	b_resid
+
+#define	FALSE	0
+#define	TRUE	1
+typedef	u_char	bool_t;
+
+static char *fixlabel __P((char *dname, int unit, int slice,
+			   struct diskslice *sp, struct disklabel *lp));
+static void partition_info __P((char *dname, int unit, int slice,
+				int part, struct partition *pp));
+static void slice_info __P((char *dname, int unit, int slice,
+			    struct diskslice *sp));
+
+/*
+ * Determine the size of the transfer, and make sure it is
+ * within the boundaries of the partition. Adjust transfer
+ * if needed, and signal errors or early completion.
+ *
+ * XXX TODO:
+ *	o Do bad sector remapping.  May need to split buffer.
+ *	o Split buffers that are too big for the device.
+ *	o Check for overflow.
+ *	o Finish cleaning this up.
+ */
+int
+dscheck(bp, ssp)
+	struct buf *bp;
+	struct diskslices *ssp;
+{
+	daddr_t	blkno;
+	daddr_t	labelsect;
+	struct disklabel *lp;
+	u_long	maxsz;
+	struct partition *pp;
+	struct diskslice *sp;
+	long	sz;
+
+	sp = &ssp->dss_slices[dkslice(bp->b_dev)];
+	lp = sp->ds_label;
+	sz = (bp->b_bcount + DEV_BSIZE - 1) >> DEV_BSHIFT;
+	if (lp == NULL) {
+		blkno = bp->b_blkno;
+		labelsect = -LABELSECTOR - 1;
+		maxsz = sp->ds_size;
+	} else {
+		labelsect = lp->d_partitions[LABEL_PART].p_offset;
+if (labelsect != 0) Debugger("");
+		pp = &lp->d_partitions[dkpart(bp->b_dev)];
+		blkno = pp->p_offset + bp->b_blkno;
+		maxsz = pp->p_size;
+		if (sp->ds_bad != NULL) {
+			daddr_t	newblkno;
+
+			newblkno = transbad144(sp->ds_bad, blkno);
+			if (newblkno != blkno)
+				printf("bad block %lu -> %lu\n",
+				       blkno, newblkno);
+		}
+	}
+
+	/* overwriting disk label ? */
+	/* XXX should also protect bootstrap in first 8K */
+	if (blkno <= LABELSECTOR + labelsect &&
+#if LABELSECTOR != 0
+	    bp->b_blkno + sz > LABELSECTOR + labelsect &&
+#endif
+	    (bp->b_flags & B_READ) == 0 && sp->ds_wlabel == 0) {
+		bp->b_error = EROFS;
+		goto bad;
+	}
+
+#if defined(DOSBBSECTOR) && defined(notyet)
+	/* overwriting master boot record? */
+	if (blkno <= DOSBBSECTOR && (bp->b_flags & B_READ) == 0 &&
+	    sp->ds_wlabel == 0) {
+		bp->b_error = EROFS;
+		goto bad;
+	}
+#endif
+
+	/* beyond partition? */
+	if (bp->b_blkno < 0 || bp->b_blkno + sz > maxsz) {
+		/* if exactly at end of disk, return an EOF */
+		if (bp->b_blkno == maxsz) {
+			bp->b_resid = bp->b_bcount;
+			return (0);
+		}
+		/* or truncate if part of it fits */
+		sz = maxsz - bp->b_blkno;
+		if (sz <= 0) {
+			bp->b_error = EINVAL;
+			goto bad;
+		}
+		bp->b_bcount = sz << DEV_BSHIFT;
+	}
+
+	/* calculate cylinder for disksort to order transfers with */
+	bp->b_pblkno = blkno + sp->ds_offset;
+
+	if (lp == NULL)
+		bp->b_cylinder = 0;	/* XXX all 0 would be better */
+	else
+		bp->b_cylinder = bp->b_pblkno / lp->d_secpercyl;
+	return (1);
+
+bad:
+	bp->b_flags |= B_ERROR;
+	return (-1);
+}
+
+void
+dsclose(dev, mode, ssp)
+	dev_t	dev;
+	int	mode;
+	struct diskslices *ssp;
+{
+	u_char	mask;
+	struct diskslice *sp;
+
+	sp = &ssp->dss_slices[dkslice(dev)];
+	mask = 1 << dkpart(dev);
+	switch (mode) {
+	case S_IFBLK:
+		sp->ds_bopenmask &= ~mask;
+		break;
+	case S_IFCHR:
+		sp->ds_copenmask &= ~mask;
+		break;
+	}
+	sp->ds_openmask = sp->ds_bopenmask | sp->ds_copenmask;
+}
+
+/*
+ * For the "write" commands (DIOCSBAD, DIOCSDINFO and DIOCWDINFO), this
+ * is subject to the same restriction as dsopen().
+ */
+int
+dsioctl(dev, cmd, data, flags, ssp, strat, setgeom)
+	dev_t	dev;
+	int	cmd;
+	caddr_t	data;
+	int	flags;
+	struct diskslices *ssp;
+	d_strategy_t *strat;
+	ds_setgeom_t *setgeom;
+{
+	int	error;
+	struct disklabel *lp;
+	int	old_wlabel;
+	struct diskslice *sp;
+
+	sp = &ssp->dss_slices[dkslice(dev)];
+	lp = sp->ds_label;
+	switch (cmd) {
+
+	case DIOCGDINFO:
+		if (lp == NULL)
+			return (EINVAL);
+		*(struct disklabel *)data = *lp;
+		return (0);
+
+#ifdef notyet
+	case DIOCGDINFOP:
+		if (lp == NULL)
+			return (EINVAL);
+		*(struct disklabel **)data = lp;
+		return (0);
+#endif
+
+	case DIOCGPART:
+		if (lp == NULL)
+			return (EINVAL);
+		((struct partinfo *)data)->disklab = lp;
+		((struct partinfo *)data)->part
+			= &lp->d_partitions[dkpart(dev)];
+		return (0);
+
+	case DIOCSBAD:
+		if (!(flags & FWRITE))
+			return (EBADF);
+		if (lp == NULL)
+			return (EINVAL);
+		if (sp->ds_bad != NULL)
+			free(sp->ds_bad, M_DEVBUF);
+		sp->ds_bad = internbad144((struct dkbad *)data, lp);
+		return (0);
+
+	case DIOCSDINFO:
+		if (!(flags & FWRITE))
+			return (EBADF);
+		lp = malloc(sizeof *lp, M_DEVBUF, M_WAITOK);
+		error = setdisklabel(lp, (struct disklabel *)data,
+				     sp->ds_label != NULL
+				     ? sp->ds_openmask : (u_long)0);
+#if 0 /* XXX */
+		if (error != 0 && setgeom != NULL)
+			error = setgeom(lp);
+#endif
+		if (error != 0) {
+			free(lp, M_DEVBUF);
+			return (error);
+		}
+		if (sp->ds_label != NULL)
+			free(sp->ds_label, M_DEVBUF);
+		sp->ds_label = lp;
+		return (0);
+
+	case DIOCWDINFO:
+		error = dsioctl(dev, DIOCSDINFO, data, flags, ssp, strat,
+				setgeom);
+		if (error != 0)
+			return (error);
+		/*
+		 * XXX this used to hack on dk_openpart to fake opening
+		 * partition 0 in case that is used instead of dkpart(dev).
+		 */
+		old_wlabel = sp->ds_wlabel;
+		sp->ds_wlabel = TRUE;
+		error = writedisklabel(dev, strat, sp->ds_label);
+		sp->ds_wlabel = old_wlabel;
+		return (error);
+
+	case DIOCWLABEL:
+		if (!(flags & FWRITE))
+			return (EBADF);
+		sp->ds_wlabel = (*(int *)data != 0);
+		return (0);
+
+	default:
+		return (-1);
+	}
+}
+
+/*
+ * This should only be called when the unit is inactive and the strategy
+ * routine should not allow it to become active unless we call it.  Our
+ * strategy routine must be special to allow activity.
+ */
+int
+dsopen(dname, dev, mode, sspp, lp, strat, setgeom)
+	char	*dname;
+	dev_t	dev;
+	int	mode;
+	struct diskslices **sspp;
+	struct disklabel *lp;
+	d_strategy_t *strat;
+	ds_setgeom_t *setgeom;
+{
+	int	error;
+	char	*msg;
+	u_char	mask;
+	bool_t	need_init;
+	int	part;
+	int	slice;
+	struct diskslice *sp;
+	struct diskslices *ssp;
+	int	unit;
+
+	need_init = TRUE;
+	if (*sspp != NULL) {
+		/*
+		 * XXX reinitialize the slice table unless there is an open
+		 * device on the unit.  This should only be done if the media
+		 * has changed.
+		 */
+		for (slice = 0, ssp = *sspp; slice < ssp->dss_nslices; slice++)
+			if (ssp->dss_slices[slice].ds_openmask) {
+				need_init = FALSE;
+				break;
+			}
+		if (need_init)
+			for (slice = 0, ssp = *sspp; slice < ssp->dss_nslices;
+			     slice++) {
+				sp = &ssp->dss_slices[slice];
+				if (sp->ds_bad != NULL) {
+					free(sp->ds_bad, M_DEVBUF);
+					sp->ds_bad = NULL;
+				}
+				if (sp->ds_label != NULL) {
+					free(sp->ds_label, M_DEVBUF);
+					sp->ds_label = NULL;
+				}
+			}
+	}
+	if (need_init) {
+		printf("dsinit\n");
+		error = dsinit(dname, dev, strat, lp, sspp);
+		if (error != 0)
+			return (error);
+		if (setgeom != NULL) {
+			error = setgeom(lp);
+			if (error != 0)
+				/* XXX clean up? */
+				return (error);
+		}
+	}
+	ssp = *sspp;
+	slice = dkslice(dev);
+	if (slice >= ssp->dss_nslices)
+		return (ENXIO);
+	sp = &ssp->dss_slices[slice];
+	part = dkpart(dev);
+	unit = dkunit(dev);
+	if (/* slice != WHOLE_DISK_SLICE && */ sp->ds_label == NULL) {
+		struct disklabel *lp1;
+
+		lp1 = malloc(sizeof *lp1, M_DEVBUF, M_WAITOK);
+		*lp1 = *lp;
+		lp = lp1;	
+		printf("readdisklabel\n");
+		msg = correct_readdisklabel(dkmodpart(dev, RAW_PART), strat, lp);
+#if 0 /* XXX */
+		if (msg == NULL && setgeom != NULL && setgeom(lp) != 0)
+			msg = "setgeom failed";
+#endif
+		if (msg == NULL)
+			msg = fixlabel(dname, unit, slice, sp, lp);
+		if (msg != NULL) {
+			free(lp, M_DEVBUF);
+			log(LOG_WARNING, "%s%ds%d: cannot find label (%s)\n",
+			    dname, unit, slice, msg);
+			if (part == RAW_PART)
+				goto out;
+			return (EINVAL);	/* XXX needs translation */
+		}
+		if (lp->d_flags & D_BADSECT) {
+			struct dkbad *btp;
+
+			btp = malloc(sizeof *btp, M_DEVBUF, M_WAITOK);
+			printf("readbad144\n");
+			msg = readbad144(dev, strat, lp, btp);
+			if (msg != NULL) {
+				log(LOG_WARNING,
+				"%s%ds%d: cannot find bad sector table (%s)\n",
+				    dname, unit, slice, msg);
+				free(btp, M_DEVBUF);
+				free(lp, M_DEVBUF);
+				if (part == RAW_PART)
+					goto out;
+				return (EINVAL);  /* XXX needs translation */
+			}
+			sp->ds_bad = internbad144(btp, lp);
+			free(btp, M_DEVBUF);
+			if (sp->ds_bad == NULL) {
+				free(lp, M_DEVBUF);
+				if (part == RAW_PART)
+					goto out;
+				return (EINVAL);  /* XXX needs translation */
+			}
+		}
+		sp->ds_label = lp;
+		sp->ds_wlabel = TRUE;
+	}
+	if (part != RAW_PART
+	    && (sp->ds_label == NULL || part >= sp->ds_label->d_npartitions))
+		return (EINVAL);	/* XXX needs translation */
+out:
+	mask = 1 << part;
+	switch (mode) {
+	case S_IFBLK:
+		sp->ds_bopenmask |= mask;
+		break;
+	case S_IFCHR:
+		sp->ds_copenmask |= mask;
+		break;
+	}
+	sp->ds_openmask = sp->ds_bopenmask | sp->ds_copenmask;
+	return (0);
+}
+
+static char *
+fixlabel(dname, unit, slice, sp, lp)
+	char	*dname;
+	int	unit;
+	int	slice;
+	struct diskslice *sp;
+	struct disklabel *lp;
+{
+	bool_t	adjust;
+	int	bsdpart;
+	struct partition *pp;
+	bool_t	warned;
+
+	pp = &lp->d_partitions[LABEL_PART];
+	if (pp->p_offset != 0 && pp->p_offset != sp->ds_offset) {
+		printf(
+"%s%ds%d: rejecting BSD label: label partition start != 0 and != slice start\n",
+		       dname, unit, slice);
+		slice_info(dname, unit, slice, sp);
+		partition_info(dname, unit, slice, LABEL_PART, pp);
+		return ("invalid partition table");
+	}
+	if (pp->p_size != sp->ds_size) {
+		printf("%s%ds%d: label partition size != slice size\n",
+		       dname, unit, slice);
+		slice_info(dname, unit, slice, sp);
+		partition_info(dname, unit, slice, LABEL_PART, pp);
+		if (pp->p_size > sp->ds_size) {
+			printf("%s%ds%d: truncating label partition\n",
+			       dname, unit, slice);
+			pp->p_size = sp->ds_size;
+		}
+	}
+	adjust = FALSE;
+	warned = FALSE;
+	if (pp->p_offset != 0) {
+		printf("%s%ds%d: adjusting offsets in BSD label\n",
+		       dname, unit, slice);
+		slice_info(dname, unit, slice, sp);
+		partition_info(dname, unit, slice, LABEL_PART, pp);
+		adjust = TRUE;
+		warned = TRUE;
+	}
+	pp -= LABEL_PART;
+	for (bsdpart = 0; bsdpart < lp->d_npartitions; bsdpart++, pp++) {
+		if (adjust && (pp->p_offset != 0 || pp->p_size != 0))
+			pp->p_offset -= sp->ds_offset;
+		if (pp->p_offset + pp->p_size > sp->ds_size
+		    || pp->p_offset + pp->p_size < pp->p_offset) {
+			printf(
+"%s%ds%d: rejecting partition in BSD label: it isn't entirely within the slice\n",
+			       dname, unit, slice);
+			if (!warned) {
+				slice_info(dname, unit, slice, sp);
+				warned = TRUE;
+			}
+			if (adjust)
+				pp->p_offset += sp->ds_offset;
+			partition_info(dname, unit, slice, bsdpart, pp);
+			bzero(pp, sizeof *pp);
+		}
+	}
+
+	/* XXX TODO: fix general params in *lp? */
+
+	return (NULL);
+}
+
+static void
+partition_info(dname, unit, slice, part, pp)
+	char	*dname;
+	int	unit;
+	int	slice;
+	int	part;
+	struct partition *pp;
+{
+	printf("%s%ds%d%c: start %lu, end %lu, size %lu\n",
+	       dname, unit, slice, 'a' + part,
+	       pp->p_offset, pp->p_offset + pp->p_size - 1, pp->p_size);
+}
+
+static void
+slice_info(dname, unit, slice, sp)
+	char	*dname;
+	int	unit;
+	int	slice;
+	struct diskslice *sp;
+{
+	printf("%s%ds%d: start %lu, end %lu, size %lu\n",
+	       dname, unit, slice,
+	       sp->ds_offset, sp->ds_offset + sp->ds_size - 1, sp->ds_size);
+}
--- a/sys/kern/subr_dkbad.c
+++ b/sys/kern/subr_dkbad.c
@ -0,0 +1,158 @@
+/*-
+ * Copyright (c) 1994 Bruce D. Evans.
+ * All rights reserved.
+ *
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * William Jolitz.
+ *
+ * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	from: @(#)wd.c	7.2 (Berkeley) 5/9/91
+ *	from: wd.c,v 1.55 1994/10/22 01:57:12 phk Exp $
+ *	from: @(#)ufs_disksubr.c	7.16 (Berkeley) 5/4/91
+ *	from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $
+ *	$Id:
+ */
+
+#include <sys/param.h>
+#include <sys/buf.h>
+#include <sys/disklabel.h>
+#include <sys/dkbad.h>
+#include <sys/malloc.h>
+
+/*
+ * Internalize the bad sector table.
+ * TODO:
+ *	o Fix types.
+ *	  Type long should be daddr_t since we compare with blkno's.
+ *	  Sentinel -1 should be ((daddr_t)-1).
+ *	o Can remove explicit test for sentinel if it is a positive
+ *	  (unsigned or not) value larger than all possible blkno's.
+ *	o Check that the table is sorted.
+ *	o Use faster searches.
+ *	o Use the internal table in wddump().
+ *	o Don't duplicate so much code.
+ *	o Do all bad block handing in a driver-independent file.
+ *	o Remove limit of 126 spare sectors.
+ */
+struct dkbad_intern *
+internbad144(btp, lp)
+	struct dkbad *btp;
+	struct disklabel *lp;
+{
+	struct dkbad_intern *bip;
+	int i;
+
+	bip = malloc(sizeof *bip, M_DEVBUF, M_WAITOK);
+	/*
+	 * Spare sectors are allocated beginning with the last sector of
+	 * the second last track of the disk (the last track is used for
+	 * the bad sector list).
+	 */
+	bip->bi_maxspare = lp->d_secperunit - lp->d_nsectors - 1;
+	bip->bi_nbad = DKBAD_MAXBAD;
+	i = 0;
+	for (; i < DKBAD_MAXBAD && btp->bt_bad[i].bt_cyl != DKBAD_NOCYL; i++)
+		bip->bi_bad[i] = btp->bt_bad[i].bt_cyl * lp->d_secpercyl
+				 + (btp->bt_bad[i].bt_trksec >> 8)
+				   * lp->d_nsectors
+				 + (btp->bt_bad[i].bt_trksec & 0x00ff);
+	bip->bi_bad[i] = -1;
+	return (bip);
+}
+
+char *
+readbad144(dev, strat, lp, bdp)
+	dev_t	dev;
+	d_strategy_t *strat;
+	struct disklabel *lp;
+	struct dkbad *bdp;
+{
+	struct buf *bp;
+	struct dkbad *db;
+	int	i;
+	char	*msg;
+
+	bp = geteblk((int)lp->d_secsize);
+	i = 0;
+	do {
+		/* Read a bad sector table. */
+		bp->b_dev = dev;
+		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_flags = B_BUSY | B_READ;
+		(*strat)(bp);
+
+		/* If successful, validate, otherwise try another. */
+		if (biowait(bp) == 0) {
+			db = (struct dkbad *)(bp->b_un.b_addr);
+			if (db->bt_mbz == 0 && db->bt_flag == DKBAD_MAGIC) {
+				msg = NULL;
+				*bdp = *db;
+				break;
+			}
+			msg = "bad sector table corrupted";
+		} else
+			msg = "bad sector table I/O error";
+	} while ((bp->b_flags & B_ERROR) && (i += 2) < 10 &&
+		 i < lp->d_nsectors);
+	bp->b_flags = B_INVAL | B_AGE;
+	brelse(bp);
+	return (msg);
+}
+
+daddr_t
+transbad144(bip, blkno)
+	struct dkbad_intern *bip;
+	daddr_t	blkno;
+{
+	int	i;
+
+	/*
+	 * List is sorted, so the search can terminate when it is past our
+	 * sector.
+	 */
+	for (i = 0; bip->bi_bad[i] != -1 && bip->bi_bad[i] <= blkno; i++)
+		if (bip->bi_bad[i] == blkno)
+			/*
+			 * Spare sectors are allocated in decreasing order.
+			 */
+			return (bip->bi_maxspare - i);
+	return (blkno);
+}