/*
 * Copyright (c) 1994 Gordon W. Ross (Sun3 changes)
 * 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: i386/disksubr.c,v 1.4 1994/01/11 16:38:48 mycroft
 *	$Id: disksubr.c,v 1.6 1994/07/23 03:27:28 gwr Exp $
 */

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

#include <sys/device.h>
#include <sys/disk.h>

#include <machine/sun_disklabel.h>

#ifdef	SCSIDEBUG
#define STATIC /* not */
#else
#define STATIC static
#endif

/* XXX encoding of disk minor numbers, should be elsewhere... */
#define dkpart(dev)		(minor(dev) & 7)

#define	b_cylin	b_resid

#if LABELSECTOR != 0
#error	"Default value of LABELSECTOR no longer zero?"
#endif

STATIC int sun_disklabel_to_bsd  (caddr_t, struct disklabel *);
STATIC int sun_disklabel_from_bsd(caddr_t, struct disklabel *);

/*
 * Attempt to read a disk label from a device
 * using the indicated stategy 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.
 *
 * Return buffer for use in signalling errors if requested.
 *
 * Returns null on success and an error string on failure.
 */
char *
readdisklabel(dev, strat, lp, osdep)
	dev_t dev;
	void (*strat)();
	register struct disklabel *lp;
	struct cpu_disklabel *osdep;
{
	register struct buf *bp;
	struct disklabel *dlp;
	struct sun_disklabel *slp;
	char *msg = NULL;

	/* minimal requirements for archtypal disk label */
	if (lp->d_secperunit == 0)
		lp->d_secperunit = 0x1fffffff;
	lp->d_npartitions = 1;
	if (lp->d_partitions[0].p_size == 0)
		lp->d_partitions[0].p_size = 0x1fffffff;
	lp->d_partitions[0].p_offset = 0;

	/* obtain buffer to probe drive with */
	bp = geteblk((int)lp->d_secsize);

	/* next, dig out disk label */
	bp->b_dev = dev;
	bp->b_blkno = LABELSECTOR;
	bp->b_cylin = 0;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags = B_BUSY | B_READ;
	(*strat)(bp);

	/* if successful, locate disk label within block and validate */
	if (biowait(bp)) {
		msg = "disk label read error";
		goto done;
	}

	slp = (struct sun_disklabel *) bp->b_un.b_addr;
	if (slp->sl_magic == SUN_DKMAGIC) {
		if (sun_disklabel_to_bsd(bp->b_un.b_addr, lp))
			msg = "SunOS disk label corrupted";
		goto done;
	}

	dlp = (struct disklabel *)(bp->b_un.b_addr + LABELOFFSET);
	if (dlp->d_magic == DISKMAGIC) {
		if (dkcksum(dlp)) {
			msg = "NetBSD disk label corrupted";
			goto done;
		}
		*lp = *dlp; 	/* struct assignment */
		goto done;
	}

	msg = "no disk label";

done:
	bp->b_flags = B_INVAL | B_AGE | B_READ;
	brelse(bp);
	return (msg);
}

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

	/* sanity clause */
	if (nlp->d_secpercyl == 0 || nlp->d_secsize == 0
		|| (nlp->d_secsize % DEV_BSIZE) != 0)
			return(EINVAL);

	/* special case to allow disklabel to be invalidated */
	if (nlp->d_magic == 0xffffffff) {
		*olp = *nlp;
		return (0);
	}

	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.
 */
writedisklabel(dev, strat, lp, osdep)
	dev_t dev;
	void (*strat)();
	register struct disklabel *lp;
	struct cpu_disklabel *osdep;
{
#if 0
	struct buf *bp;
	struct disklabel *dlp;
	struct sun_disklabel *slp;
	int error = 0, cyl, i;

	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = dev;
	bp->b_blkno = LABELSECTOR;
	bp->b_cylin = 0;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags = B_READ;		/* get current label */
	(*strat)(bp);
	if (error = biowait(bp))
		goto done;

	slp = (struct sun_disklabel *) bp->b_un.b_addr;
	if (slp->sl_magic == SUN_DKMAGIC) {
		error = sun_disklabel_from_bsd(bp->b_un.b_addr, lp);
	} else {
		dlp = (struct disklabel *)(bp->b_un.b_addr + LABELOFFSET);
		*dlp = *lp; 	/* struct assignment */
	}
	bp->b_flags = B_WRITE;
	(*strat)(bp);
	error = biowait(bp);

done:
	brelse(bp);
	return (error);
#else
	/* Not sure if the above is right yet... -gwr */
	return ENODEV;
#endif
}

/*
 * 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(struct buf *bp, struct disklabel *lp, int wlabel)
{
	struct partition *p = lp->d_partitions + dkpart(bp->b_dev);
	int labelsect = lp->d_partitions[0].p_offset;
	int maxsz = p->p_size;
	int sz = (bp->b_bcount + DEV_BSIZE - 1) >> DEV_BSHIFT;

	/* overwriting disk label ? */
	/* XXX should also protect bootstrap in first 8K */
	if (bp->b_blkno + p->p_offset <= LABELSECTOR + labelsect &&
	    (bp->b_flags & B_READ) == 0 && wlabel == 0)
	{
		bp->b_error = EROFS;
		goto bad;
	}

	/* 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_cylin = (bp->b_blkno + p->p_offset) / lp->d_secpercyl;
	return(1);

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

/* What partition types to assume for Sun disklabels: */
static u_char
sun_fstypes[8] = {
	FS_BSDFFS,	/* a */
	FS_SWAP,	/* b */
	FS_OTHER,	/* c */
	FS_OTHER,	/* d */
	FS_OTHER,	/* e */
	FS_OTHER,	/* f */
	FS_BSDFFS,	/* g */
	FS_BSDFFS,	/* h */
};

/*
 * The rest of this was taken from arch/sparc/scsi/sun_disklabel.c
 * (and then hacked severely:-)
 */

/*
 * Take a sector (cp) containing a SunOS disk label and set lp to a
 * BSD disk label.  Returns non-zero on error.
 */
STATIC int
sun_disklabel_to_bsd(cp, lp)
	register caddr_t cp;
	register struct disklabel *lp;
{
	u_short *sp;
	struct sun_disklabel *sl;
	struct partition *npp;
	struct sun_dkpart *spp;
	int i, v;

	sp = (u_short *)(cp + sizeof(struct sun_disklabel));
	--sp;
	v = 0;
	while (sp >= (u_short *)cp)
		v ^= *sp--;
	if (v)
		return v;
	sl = (struct sun_disklabel *)cp;
	lp->d_magic = 0;	/* denote as pseudo */
	lp->d_ncylinders = sl->sl_ncylinders;
	lp->d_acylinders = sl->sl_acylinders;
	v = (lp->d_ntracks = sl->sl_ntracks) *
	    (lp->d_nsectors = sl->sl_nsectors);
	lp->d_secpercyl = v;
	lp->d_npartitions = 8;

	for (i = 0; i < 8; i++) {
		spp = &sl->sl_part[i];
		npp = &lp->d_partitions[i];
		npp->p_offset = spp->sdkp_cyloffset * v;
		npp->p_size = spp->sdkp_nsectors;
		if (npp->p_size)
			npp->p_fstype = sun_fstypes[i];
	}
	return 0;
}

#if 0	/* XXX - Not yet. */
int
sun_dkioctl(dk, cmd, data, partition)
	struct dkdevice *dk;
	int cmd;
	caddr_t data;
	int partition;
{
	register struct partition *p;

	switch (cmd) {

	case DKIOCGGEOM:
#define geom ((struct sun_dkgeom *)data)
		bzero(data, sizeof(*geom));
		geom->sdkc_ncylinders = dk->dk_label.d_ncylinders;
		geom->sdkc_acylinders = dk->dk_label.d_acylinders;
		geom->sdkc_ntracks = dk->dk_label.d_ntracks;
		geom->sdkc_nsectors = dk->dk_label.d_nsectors;
		geom->sdkc_interleave = dk->dk_label.d_interleave;
		geom->sdkc_sparespercyl = dk->dk_label.d_sparespercyl;
		geom->sdkc_rpm = dk->dk_label.d_rpm;
		geom->sdkc_pcylinders =
		    dk->dk_label.d_ncylinders + dk->dk_label.d_acylinders;
#undef	geom
		break;

	case DKIOCINFO:
		/* Homey don't do DKIOCINFO */
		bzero(data, sizeof(struct sun_dkctlr));
		break;

	case DKIOCGPART:
		if (dk->dk_label.d_secpercyl == 0)
			return (ERANGE);	/* XXX */
		p = &dk->dk_label.d_partitions[partition];
		if (p->p_offset % dk->dk_label.d_secpercyl != 0)
			return (ERANGE);	/* XXX */
#define part ((struct sun_dkpart *)data)
		part->sdkp_cyloffset = p->p_offset / dk->dk_label.d_secpercyl;
		part->sdkp_nsectors = p->p_size;
#undef	part
		break;

	default:
		return (-1);
	}
	return (0);
}
#endif 0


/* XXX - Where does this belong? */
void
dk_establish(dk, dev)
	struct dkdevice *dk;
	struct device *dev;
{
	/* XXX - Is this OK? -gwr */
}