path: root/sys/arch/hp300/hp300/disksubr.c

/*	$OpenBSD: disksubr.c,v 1.21 2006/09/24 22:43:00 krw Exp $	*/
/*	$NetBSD: disksubr.c,v 1.9 1997/04/01 03:12:13 scottr Exp $	*/

/*
 * Copyright (c) 1982, 1986, 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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. 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.
 *
 *	@(#)ufs_disksubr.c	8.5 (Berkeley) 1/21/94
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/disk.h>
#include <sys/disklabel.h>
#include <sys/syslog.h>

/*
 * Attempt to read a disk label from a device using the indicated strategy
 * routine.  The label must be partly set up before this: secpercyl and
 * anything required in the strategy routine (e.g., sector size) must be
 * filled in before calling us.  Returns null on success and an error
 * string on failure.
 */
char *
readdisklabel(dev, strat, lp, osdep, spoofonly)
	dev_t dev;
	void (*strat)(struct buf *);
	struct disklabel *lp;
	struct cpu_disklabel *osdep;
	int spoofonly;
{
	struct buf *bp;
	struct disklabel *dlp;
	char *msg = NULL;

	/* minimal requirements for archetypal disk label */
	if (lp->d_secsize < DEV_BSIZE)
		lp->d_secsize = DEV_BSIZE;
	if (lp->d_secperunit == 0)
		lp->d_secperunit = 0x1fffffff;
	if (lp->d_secpercyl == 0)
		return ("invalid geometry");
	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 = lp->d_secperunit;
	lp->d_partitions[i].p_offset = 0;

	/* don't read the on-disk label if we are in spoofed-only mode */
	if (spoofonly)
		return (NULL);

	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = dev;
	bp->b_blkno = LABELSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags = B_BUSY | B_READ;
	bp->b_cylinder = LABELSECTOR / lp->d_secpercyl;
	(*strat)(bp);
	if (biowait(bp))
		msg = "disk label I/O error";
	else for (dlp = (struct disklabel *)bp->b_data;
	    dlp <= (struct disklabel *)((char *)bp->b_data +
	    DEV_BSIZE - sizeof(*dlp));
	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
		if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC) {
			if (msg == NULL) {
#if defined(CD9660)
				if (iso_disklabelspoof(dev, strat, lp) != 0)
#endif
					msg = "no disk label";
#if defined(UDF)
				if (msg && udf_disklabelspoof(dev, strat, lp) == 0)
					msg = NULL;
#endif
			}
		} else if (dlp->d_npartitions > MAXPARTITIONS ||
			   dkcksum(dlp) != 0)
			msg = "disk label corrupted";
		else {
			*lp = *dlp;
			msg = NULL;
			break;
		}
	}
	bp->b_flags = B_INVAL | B_AGE;
	brelse(bp);
	return (msg);
}

/*
 * Check new disk label for sensibility before setting it.
 */
int
setdisklabel(olp, nlp, openmask, osdep)
	struct disklabel *olp, *nlp;
	u_long openmask;
	struct cpu_disklabel *osdep;
{
	int i;
	struct partition *opp, *npp;

	if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC ||
	    dkcksum(nlp) != 0)
		return (EINVAL);
	while ((i = ffs((long)openmask)) != 0) {
		i--;
		openmask &= ~(1 << i);
		if (nlp->d_npartitions <= i)
			return (EBUSY);
		opp = &olp->d_partitions[i];
		npp = &nlp->d_partitions[i];
		if (npp->p_offset != opp->p_offset || npp->p_size < opp->p_size)
			return (EBUSY);
		/*
		 * Copy internally-set partition information
		 * if new label doesn't include it.		XXX
		 */
		if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) {
			npp->p_fstype = opp->p_fstype;
			npp->p_fsize = opp->p_fsize;
			npp->p_frag = opp->p_frag;
			npp->p_cpg = opp->p_cpg;
		}
	}
	nlp->d_checksum = 0;
	nlp->d_checksum = dkcksum(nlp);
	*olp = *nlp;
	return (0);
}

/*
 * Write disk label back to device after modification.
 */
int
writedisklabel(dev, strat, lp, osdep)
	dev_t dev;
	void (*strat)(struct buf *);
	struct disklabel *lp;
	struct cpu_disklabel *osdep;
{
	struct buf *bp;
	struct disklabel *dlp;
	int labelpart;
	int error = 0;

	labelpart = DISKPART(dev);
	if (lp->d_partitions[labelpart].p_offset != 0) {
		if (lp->d_partitions[0].p_offset != 0)
			return (EXDEV);			/* not quite right */
		labelpart = 0;
	}
	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = MAKEDISKDEV(major(dev), DISKUNIT(dev), labelpart);
	bp->b_blkno = LABELSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags = B_READ;
	(*strat)(bp);
	if ((error = biowait(bp)))
		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 &&
		    dkcksum(dlp) == 0) {
			*dlp = *lp;
			bp->b_flags = B_WRITE;
			(*strat)(bp);
			error = biowait(bp);
			goto done;
		}
	}
	/* Write it in the regular place. */
	*(struct disklabel *)bp->b_data = *lp;
	bp->b_flags = B_BUSY | B_WRITE;
	(*strat)(bp);
	error = biowait(bp);
	goto done;

done:
	brelse(bp);
	return (error);
}

/*
 * 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.
 */
int
bounds_check_with_label(bp, lp, osdep, wlabel)
	struct buf *bp;
	struct disklabel *lp;
	struct cpu_disklabel *osdep;
	int wlabel;
{
#define blockpersec(count, lp) ((count) * (((lp)->d_secsize) / DEV_BSIZE))
	struct partition *p = &lp->d_partitions[DISKPART(bp->b_dev)];
	int labelsect = blockpersec(lp->d_partitions[0].p_offset, lp) +
	    LABELSECTOR;
	int sz = howmany(bp->b_bcount, DEV_BSIZE);

	/* avoid division by zero */
	if (lp->d_secpercyl == 0) {
		bp->b_error = EINVAL;
		goto bad;
	}

	/* Overwriting disk label? */
	if (bp->b_blkno + blockpersec(p->p_offset, lp) <= labelsect &&
	    (bp->b_flags & B_READ) == 0 && !wlabel) {
		bp->b_error = EROFS;
		goto bad;
	}

	/* beyond partition? */
	if (bp->b_blkno + sz > blockpersec(p->p_size, lp)) {
		sz = blockpersec(p->p_size, lp) - bp->b_blkno;
		if (sz == 0) {
			/* If exactly at end of disk, return EOF. */
			bp->b_resid = bp->b_bcount;
			return (0);
		}
		if (sz < 0) {
			bp->b_error = EINVAL;
			goto bad;
		}
		/* ... or truncate if part of it fits */
		bp->b_bcount = sz << DEV_BSHIFT;
	}

	/* calculate cylinder for disksort to order transfers with */
	bp->b_resid = (bp->b_blkno + blockpersec(p->p_offset, lp)) /
	    lp->d_secpercyl;
	return (1);

bad:
	bp->b_flags |= B_ERROR;
	return (-1);
}