Пример #1
0
/*
 * 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.
 *
 * 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)
{
	int spoofonly = 0;
	struct buf *bp = NULL;
	const char *msg = "no disk label";
	int i;
	struct disklabel fallbacklabel;

	/* minimal requirements for archetypal disk label */
	if (lp->d_secsize == 0)
		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 = 0x1fffffff;
	lp->d_partitions[i].p_offset = 0;
	fallbacklabel = *lp;

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

	msg = readliflabel(bp, strat, lp, osdep, 0, 0, spoofonly);

#if defined(CD9660)
	if (msg && iso_disklabelspoof(dev, strat, lp) == 0)
		msg = NULL;
#endif

	/* If there was an error, still provide a decent fake one.  */
	if (msg)
		*lp = fallbacklabel;

	if (bp) {
		brelse(bp, BC_INVAL);
	}
	return (msg);
}
Пример #2
0
/*
 * Write disk label back to device after modification.
 */
int
writedisklabel(dev_t dev, void (*strat)(struct buf *), struct disklabel *lp,
    struct cpu_disklabel *osdep)
{
	const char *msg = "no disk label";
	struct buf *bp;
	struct disklabel dl;
	struct cpu_disklabel cdl;
	int labeloffset, error, partoff = 0, cyl = 0;

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

	/*
	 * I once played with the thought of using osdep->label{tag,sector}
	 * as a cache for knowing where (and what) to write.  However, now I
	 * think it might be useful to reprobe if someone has written
	 * a newer disklabel of another type with disklabel(8) and -r.
	 */
	dl = *lp;
	msg = readliflabel(bp, strat, &dl, &cdl, &partoff, &cyl, 0);
	labeloffset = LABELOFFSET;

	if (msg) {
		if (partoff == -1)
			return EIO;

		/* Write it in the regular place with native byte order. */
		labeloffset = LABELOFFSET;
		bp->b_blkno = partoff + LABELSECTOR;
		bp->b_cylinder = cyl;
		bp->b_bcount = lp->d_secsize;
	}

	*(struct disklabel *)((char *)bp->b_data + labeloffset) = *lp;

	bp->b_cflags = BC_BUSY;
	bp->b_flags = B_WRITE;
	(*strat)(bp);
	error = biowait(bp);

	brelse(bp, BC_INVAL);
	return (error);
}
Пример #3
0
/*
 * Write disk label back to device after modification.
 */
int
writedisklabel(dev_t dev, void (*strat)(struct buf *), struct disklabel *lp)
{
	int error = EIO, partoff = -1;
	int offset;
	struct disklabel *dlp;
	struct buf *bp = NULL;

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

	if (readliflabel(bp, strat, lp, &partoff, 1) == 0) {
		bp->b_blkno = partoff + LABELSECTOR;
		offset = LABELOFFSET;
	} else if (readdoslabel(bp, strat, lp, &partoff, 1) == 0) {
		bp->b_blkno = DL_BLKTOSEC(lp, partoff + DOS_LABELSECTOR) *
		    DL_BLKSPERSEC(lp);
		offset = DL_BLKOFFSET(lp, partoff + DOS_LABELSECTOR);
	} else
		goto done;

	/* Read it in, slap the new label in, and write it back out */
	bp->b_bcount = lp->d_secsize;
	CLR(bp->b_flags, B_READ | B_WRITE | B_DONE);
	SET(bp->b_flags, B_BUSY | B_READ | B_RAW);
	(*strat)(bp);
	if ((error = biowait(bp)) != 0)
		goto done;

	dlp = (struct disklabel *)(bp->b_data + offset);
	*dlp = *lp;
	CLR(bp->b_flags, B_READ | B_WRITE | B_DONE);
	SET(bp->b_flags, B_BUSY | B_WRITE | B_RAW);
	(*strat)(bp);
	error = biowait(bp);

done:
	if (bp) {
		bp->b_flags |= B_INVAL;
		brelse(bp);
	}
	disk_change = 1;
	return (error);
}
Пример #4
0
/*
 * 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.
 */
int
readdisklabel(dev_t dev, void (*strat)(struct buf *),
    struct disklabel *lp, int spoofonly)
{
	struct buf *bp = NULL;
	int error;

	if ((error = initdisklabel(lp)))
		goto done;

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

	error = readliflabel(bp, strat, lp, NULL, spoofonly);
	if (error == 0)
		goto done;

	error = readdoslabel(bp, strat, lp, NULL, spoofonly);
	if (error == 0)
		goto done;

#if defined(CD9660)
	error = iso_disklabelspoof(dev, strat, lp);
	if (error == 0)
		goto done;
#endif
#if defined(UDF)
	error = udf_disklabelspoof(dev, strat, lp);
	if (error == 0)
		goto done;
#endif

done:
	if (bp) {
		bp->b_flags |= B_INVAL;
		brelse(bp);
	}
	disk_change = 1;
	return (error);
}