xref: /illumos-gate/usr/src/uts/common/sys/dkbad.h (revision 2d6eb4a5)

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 1991,1997-1998 by Sun Microsystems, Inc.
 * All rights reserved.
 */

#ifndef	_SYS_DKBAD_H
#define	_SYS_DKBAD_H

#ifdef	__cplusplus
extern "C" {
#endif

/*
 * Definitions needed to perform bad sector
 * revectoring ala DEC STD 144.
 *
 * The bad sector information is located in the
 * first 5 even numbered sectors of the last
 * track of the disk pack.  There are five
 * identical copies of the information, described
 * by the dkbad structure.
 *
 * Replacement sectors are allocated starting with
 * the first sector before the bad sector information
 * and working backwards towards the beginning of
 * the disk.  A maximum of 126 bad sectors are supported.
 * The position of the bad sector in the bad sector table
 * determines which replacement sector it corresponds to.
 *
 * The bad sector information and replacement sectors
 * are conventionally only accessible through the
 * 'c' file system partition of the disk.  If that
 * partition is used for a file system, the user is
 * responsible for making sure that it does not overlap
 * the bad sector information or any replacement sector.s
 */

#define	NDKBAD		126		/* # of entries maximum */

struct dkbad {
	long	bt_csn;			/* cartridge serial number */
	ushort_t bt_mbz;		/* unused; should be 0 */
	ushort_t bt_flag;		/* -1 => alignment cartridge */
	struct bt_bad {
		short	bt_cyl;		/* cylinder number of bad sector */
		short	bt_trksec;	/* track and sector number */
	} bt_bad[NDKBAD];
};

#ifdef	__cplusplus
}
#endif

#endif	/* _SYS_DKBAD_H */