Source to i386/stand/bootxx.c
/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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.
*
* @(#)bootxx.c 8.1 (Berkeley) 6/11/93
*/
#include <sys/param.h>
#include <sys/reboot.h>
#include <sys/disklabel.h>
#include <a.out.h>
#include <stand/saio.h>
char *bootprog = "/boot";
extern int opendev, bootdev, cyloffset;
extern struct disklabel disklabel;
/*
* Boot program... loads /boot out of filesystem indicated by arguements.
* We assume an autoboot unless we detect a misconfiguration.
*/
main(dev, unit, off)
{
register struct disklabel *lp;
register int io, partition, howto;
/* are we a disk, if so look at disklabel and do things */
lp = &disklabel;
if (lp->d_magic == DISKMAGIC) {
/*
* Synthesize bootdev from dev, unit, type and partition
* information from the block 0 bootstrap.
* It's dirty work, but someone's got to do it.
* This will be used by the filesystem primatives, and
* drivers. Ultimately, opendev will be created corresponding
* to which drive to pass to top level bootstrap.
*/
for (io = 0; io < 8; io++)
#ifdef notyetSCSI
if (lp->d_type == DTYPE_SCSI) {
if (lp->d_partitions[io].p_offset == off)
break;
} else
#endif
if (lp->d_partitions[io].p_offset == off*lp->d_secpercyl)
break;
if (io == 8) goto screwed;
cyloffset = off;
} else {
screwed:
/* probably a bad or non-existant disklabel */
io = 0 ;
howto |= RB_SINGLE|RB_ASKNAME ;
}
/* construct bootdev */
/* currently, PC has no way of booting off alternate controllers */
bootdev = MAKEBOOTDEV(/*i_dev*/ dev, /*i_adapt*/0, /*i_ctlr*/0,
unit, /*i_part*/io);
printf("loading %s\n", bootprog);
io = open(bootprog, 0);
if (io >= 0)
copyunix(io, howto);
_stop("boot failed\n");
}
/*ARGSUSED*/
copyunix(io, howto)
register io;
{
struct exec x;
register int i;
char *addr;
i = read(io, (char *)&x, sizeof x);
if (i != sizeof x ||
(x.a_magic != 0407 && x.a_magic != 0413 && x.a_magic != 0410))
_stop("Bad format\n");
if ((x.a_magic == 0413 || x.a_magic == 0410) &&
lseek(io, 0x400, 0) == -1)
goto shread;
if (read(io, (char *)0, x.a_text) != x.a_text)
goto shread;
addr = (char *)x.a_text;
if (x.a_magic == 0413 || x.a_magic == 0410)
while ((int)addr & CLOFSET)
*addr++ = 0;
if (read(io, addr, x.a_data) != x.a_data)
goto shread;
addr += x.a_data;
for (i = 0; i < x.a_bss; i++)
*addr++ = 0;
(*((int (*)()) x.a_entry))(howto, opendev, cyloffset);
return;
shread:
_stop("Short read\n");
}