root/sys/sys/dkbad.h
/*      $NetBSD: dkbad.h,v 1.16 2026/07/03 21:35:57 thorpej Exp $       */

/*-
 * Copyright (c) 1982, 1986, 1993, 1994
 *      The 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. 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.
 *
 *      @(#)dkbad.h     8.2 (Berkeley) 7/10/94
 */

#ifndef _SYS_DKBAD_H_
#define _SYS_DKBAD_H_

/*
 * 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 sectors.
 */
#define NBT_BAD 126

struct dkbad {
        int32_t   bt_csn;               /* cartridge serial number */
        uint16_t bt_mbz;                /* unused; should be 0 */
        uint16_t bt_flag;               /* -1 => alignment cartridge */
        struct bt_bad {
                uint16_t bt_cyl;        /* cylinder number of bad sector */
                uint16_t bt_trksec;     /* track and sector number */
        } bt_bad[NBT_BAD];
};

#define BAD144_MAXCYLNO 0xffff          /* maximum cylinder number */
#define BAD144_MAXTRKNO 0xff            /* maximum track number */
#define BAD144_MAXSECNO 0xff            /* maximum sector number */

/*
 * An indicator that the bad block handling is available. This is used
 * to conditionally enable code that performs badblock re-mapping.
 */
#define HAS_BAD144_HANDLING

#define ECC     0
#define SSE     1
#define BSE     2
#define CONT    3

#ifdef _KERNEL
struct bad144_context;

struct bad144_context *
        bad144_init(uint32_t, uint32_t, uint32_t, uint32_t);
void    bad144_fini(struct bad144_context *);
int     bad144_set(struct bad144_context *, const struct dkbad *);
int     bad144_load(struct bad144_context *, dev_t, void (*)(struct buf *));
int     bad144_isbad_chs(const struct bad144_context *,
                         uint32_t, uint32_t, uint32_t);
int     bad144_isbad_lba(const struct bad144_context *,
                         daddr_t, int, int *);
#endif /* _KERNEL */

#endif /* _SYS_DKBAD_H_ */