freebsd-dev/sys/geom/geom_sunlabel_enc.c

173 lines
5.5 KiB
C

/*-
* Copyright (c) 2003 Jake Burkholder
* Copyright (c) 2003 Poul-Henning Kamp
* Copyright (c) 2004 Joerg Wunsch
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
/* Functions to encode or decode struct sun_disklabel into a bytestream
* of correct endianess and packing.
*
* NB! This file must be usable both in kernel and userland.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/endian.h>
#include <sys/errno.h>
#include <sys/sun_disklabel.h>
#define SL_TEXT 0x0
#define SL_TEXT_SIZEOF 0x80
#define SL_VTOC_VERS 0x80
#define SL_VTOC_NPART 0x8c
#define SL_VTOC_MAP 0x8e
#define SL_VTOC_SANITY 0xbc
#define SL_RPM 0x1a4
#define SL_PCYLINDERS 0x1a6
#define SL_SPARESPERCYL 0x1a8
#define SL_INTERLEAVE 0x1ae
#define SL_NCYLINDERS 0x1b0
#define SL_ACYLINDERS 0x1b2
#define SL_NTRACKS 0x1b4
#define SL_NSECTORS 0x1b6
#define SL_PART 0x1bc
#define SL_MAGIC 0x1fc
#define SL_CKSUM 0x1fe
#define SDKP_CYLOFFSET 0
#define SDKP_NSECTORS 0x4
#define SDKP_SIZEOF 0x8 /* size of a partition entry */
#define SVTOC_TAG 0
#define SVTOC_FLAG 0x2
#define SVTOC_SIZEOF 0x4 /* size of a VTOC tag/flag entry */
/*
* Decode the relevant fields of a sun disk label, and return zero if the
* magic and checksum works out OK.
*/
int
sunlabel_dec(void const *pp, struct sun_disklabel *sl)
{
const uint8_t *p;
size_t i;
u_int u;
uint32_t vtocsane;
uint16_t npart;
p = pp;
for (i = 0; i < sizeof(sl->sl_text); i++)
sl->sl_text[i] = p[SL_TEXT + i];
sl->sl_rpm = be16dec(p + SL_RPM);
sl->sl_pcylinders = be16dec(p + SL_PCYLINDERS);
sl->sl_sparespercyl = be16dec(p + SL_SPARESPERCYL);
sl->sl_interleave = be16dec(p + SL_INTERLEAVE);
sl->sl_ncylinders = be16dec(p + SL_NCYLINDERS);
sl->sl_acylinders = be16dec(p + SL_ACYLINDERS);
sl->sl_ntracks = be16dec(p + SL_NTRACKS);
sl->sl_nsectors = be16dec(p + SL_NSECTORS);
for (i = 0; i < SUN_NPART; i++) {
sl->sl_part[i].sdkp_cyloffset = be32dec(p + SL_PART +
(i * SDKP_SIZEOF) + SDKP_CYLOFFSET);
sl->sl_part[i].sdkp_nsectors = be32dec(p + SL_PART +
(i * SDKP_SIZEOF) + SDKP_NSECTORS);
}
sl->sl_magic = be16dec(p + SL_MAGIC);
vtocsane = be32dec(p + SL_VTOC_SANITY);
npart = be16dec(p + SL_VTOC_NPART);
if (vtocsane == SUN_VTOC_SANE && npart == SUN_NPART) {
/*
* Seems we've got SVR4-compatible VTOC information
* as well, decode it.
*/
sl->sl_vtoc_sane = vtocsane;
sl->sl_vtoc_vers = be32dec(p + SL_VTOC_VERS);
sl->sl_vtoc_nparts = SUN_NPART;
for (i = 0; i < SUN_NPART; i++) {
sl->sl_vtoc_map[i].svtoc_tag = be16dec(p +
SL_VTOC_MAP + (i * SVTOC_SIZEOF) + SVTOC_TAG);
sl->sl_vtoc_map[i].svtoc_flag = be16dec(p +
SL_VTOC_MAP + (i * SVTOC_SIZEOF) + SVTOC_FLAG);
}
}
for (i = u = 0; i < SUN_SIZE; i += 2)
u ^= be16dec(p + i);
if (u == 0 && sl->sl_magic == SUN_DKMAGIC)
return (0);
else
return (EINVAL);
}
/*
* Encode the relevant fields into a sun disklabel, compute new checksum.
*/
void
sunlabel_enc(void *pp, struct sun_disklabel *sl)
{
uint8_t *p;
size_t i;
u_int u;
p = pp;
for (i = 0; i < SL_TEXT_SIZEOF; i++)
p[SL_TEXT + i] = sl->sl_text[i];
be16enc(p + SL_RPM, sl->sl_rpm);
be16enc(p + SL_PCYLINDERS, sl->sl_pcylinders);
be16enc(p + SL_SPARESPERCYL, sl->sl_sparespercyl);
be16enc(p + SL_INTERLEAVE, sl->sl_interleave);
be16enc(p + SL_NCYLINDERS, sl->sl_ncylinders);
be16enc(p + SL_ACYLINDERS, sl->sl_acylinders);
be16enc(p + SL_NTRACKS, sl->sl_ntracks);
be16enc(p + SL_NSECTORS, sl->sl_nsectors);
for (i = 0; i < SUN_NPART; i++) {
be32enc(p + SL_PART + (i * SDKP_SIZEOF) + SDKP_CYLOFFSET,
sl->sl_part[i].sdkp_cyloffset);
be32enc(p + SL_PART + (i * SDKP_SIZEOF) + SDKP_NSECTORS,
sl->sl_part[i].sdkp_nsectors);
}
be16enc(p + SL_MAGIC, sl->sl_magic);
if (sl->sl_vtoc_sane == SUN_VTOC_SANE
&& sl->sl_vtoc_nparts == SUN_NPART) {
/*
* Write SVR4-compatible VTOC elements.
*/
be32enc(p + SL_VTOC_VERS, sl->sl_vtoc_vers);
be32enc(p + SL_VTOC_SANITY, SUN_VTOC_SANE);
be16enc(p + SL_VTOC_NPART, SUN_NPART);
for (i = 0; i < SUN_NPART; i++) {
be16enc(p + SL_VTOC_MAP + (i * SVTOC_SIZEOF)
+ SVTOC_TAG,
sl->sl_vtoc_map[i].svtoc_tag);
be16enc(p + SL_VTOC_MAP + (i * SVTOC_SIZEOF)
+ SVTOC_FLAG,
sl->sl_vtoc_map[i].svtoc_flag);
}
}
for (i = u = 0; i < SUN_SIZE; i += 2)
u ^= be16dec(p + i);
be16enc(p + SL_CKSUM, u);
}