7d924377ca
Factor the ufs reading code out of the i386/boot2 loader so it can be reused by for instance sparc64. Sponsored by: DARPA and NAI Labs.
673 lines
14 KiB
C
673 lines
14 KiB
C
/*
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* Copyright (c) 1998 Robert Nordier
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms are freely
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* permitted provided that the above copyright notice and this
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* paragraph and the following disclaimer are duplicated in all
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* such forms.
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*
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* This software is provided "AS IS" and without any express or
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* implied warranties, including, without limitation, the implied
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* warranties of merchantability and fitness for a particular
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* purpose.
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*/
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/*
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* $FreeBSD$
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*/
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#include <sys/param.h>
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#include <sys/reboot.h>
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#include <sys/diskslice.h>
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#include <sys/disklabel.h>
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#include <sys/dirent.h>
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#include <machine/bootinfo.h>
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#include <machine/elf.h>
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#include <stdarg.h>
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#include <a.out.h>
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#include <btxv86.h>
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#include "boot2.h"
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#include "lib.h"
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#define IO_KEYBOARD 1
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#define IO_SERIAL 2
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#define SECOND 18 /* Circa that many ticks in a second. */
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#define RBX_ASKNAME 0x0 /* -a */
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#define RBX_SINGLE 0x1 /* -s */
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#define RBX_DFLTROOT 0x5 /* -r */
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#define RBX_KDB 0x6 /* -d */
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#define RBX_CONFIG 0xa /* -c */
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#define RBX_VERBOSE 0xb /* -v */
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#define RBX_SERIAL 0xc /* -h */
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#define RBX_CDROM 0xd /* -C */
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#define RBX_GDB 0xf /* -g */
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#define RBX_MUTE 0x10 /* -m */
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#define RBX_PAUSE 0x12 /* -p */
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#define RBX_DUAL 0x1d /* -D */
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#define RBX_PROBEKBD 0x1e /* -P */
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#define RBX_NOINTR 0x1f /* -n */
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#define RBX_MASK 0x2005ffff
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#define PATH_CONFIG "/boot.config"
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#define PATH_BOOT3 "/boot/loader"
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#define PATH_KERNEL "/kernel"
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#define ARGS 0x900
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#define NOPT 14
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#define NDEV 5
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#define MEM_BASE 0x12
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#define MEM_EXT 0x15
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#define V86_CY(x) ((x) & 1)
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#define V86_ZR(x) ((x) & 0x40)
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#define DRV_HARD 0x80
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#define DRV_MASK 0x7f
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#define TYPE_AD 0
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#define TYPE_WD 1
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#define TYPE_WFD 2
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#define TYPE_FD 3
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#define TYPE_DA 4
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extern uint32_t _end;
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static const char optstr[NOPT] = "DhaCcdgmnPprsv";
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static const unsigned char flags[NOPT] = {
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RBX_DUAL,
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RBX_SERIAL,
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RBX_ASKNAME,
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RBX_CDROM,
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RBX_CONFIG,
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RBX_KDB,
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RBX_GDB,
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RBX_MUTE,
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RBX_NOINTR,
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RBX_PROBEKBD,
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RBX_PAUSE,
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RBX_DFLTROOT,
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RBX_SINGLE,
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RBX_VERBOSE
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};
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static const char *const dev_nm[] = {"ad", "wd", " ", "fd", "da"};
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static const unsigned dev_maj[] = {30, 0, 1, 2, 4};
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static struct dsk {
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unsigned drive;
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unsigned type;
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unsigned unit;
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unsigned slice;
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unsigned part;
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unsigned start;
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int init;
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} dsk;
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static char cmd[512];
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static char kname[1024];
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static uint32_t opts;
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static struct bootinfo bootinfo;
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static uint8_t ioctrl = IO_KEYBOARD;
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void exit(int);
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static void load(const char *);
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static int parse(char *);
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static ino_t lookup(const char *);
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static int xfsread(ino_t, void *, size_t);
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static ssize_t fsread(ino_t, void *, size_t);
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static int dskread(void *, unsigned, unsigned);
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static int printf(const char *,...);
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static int putchar(int);
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static uint32_t memsize(int);
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static int drvread(void *, unsigned, unsigned);
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static int keyhit(unsigned);
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static int xputc(int);
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static int xgetc(int);
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static int getc(int);
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#define memcpy __builtin_memcpy
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static inline void
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readfile(const char *fname, void *buf, size_t size)
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{
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ino_t ino;
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if ((ino = lookup(fname)))
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fsread(ino, buf, size);
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}
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static inline int
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strcmp(const char *s1, const char *s2)
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{
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for (; *s1 == *s2 && *s1; s1++, s2++);
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return (u_char)*s1 - (u_char)*s2;
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}
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#include "ufsread.c"
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static inline int
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getchar(void)
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{
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int c;
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c = xgetc(0);
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if (c == '\r')
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c = '\n';
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return c;
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}
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static inline void
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getstr(char *str, int size)
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{
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char *s;
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int c;
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s = str;
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do {
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switch (c = getchar()) {
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case 0:
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break;
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case '\b':
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case '\177':
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if (s > str) {
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s--;
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putchar('\b');
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putchar(' ');
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} else
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c = 0;
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break;
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case '\n':
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*s = 0;
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break;
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default:
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if (s - str < size - 1)
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*s++ = c;
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}
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if (c)
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putchar(c);
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} while (c != '\n');
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}
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static inline uint32_t
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drvinfo(int drive)
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{
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v86.addr = 0x13;
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v86.eax = 0x800;
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v86.edx = DRV_HARD + drive;
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v86int();
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if (V86_CY(v86.efl))
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return 0x4f010f;
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return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
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(v86.edx & 0xff00) | (v86.ecx & 0x3f);
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}
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static inline void
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putc(int c)
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{
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v86.addr = 0x10;
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v86.eax = 0xe00 | (c & 0xff);
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v86.ebx = 0x7;
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v86int();
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}
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int
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main(void)
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{
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int autoboot, i;
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dmadat = (void *)(roundup2(__base + _end, 0x10000) - __base);
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v86.ctl = V86_FLAGS;
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dsk.drive = *(uint8_t *)PTOV(ARGS);
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dsk.type = dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
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dsk.unit = dsk.drive & DRV_MASK;
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dsk.slice = *(uint8_t *)PTOV(ARGS + 1) + 1;
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bootinfo.bi_version = BOOTINFO_VERSION;
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bootinfo.bi_size = sizeof(bootinfo);
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bootinfo.bi_basemem = memsize(MEM_BASE);
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bootinfo.bi_extmem = memsize(MEM_EXT);
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bootinfo.bi_memsizes_valid++;
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for (i = 0; i < N_BIOS_GEOM; i++)
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bootinfo.bi_bios_geom[i] = drvinfo(i);
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/* Process configuration file */
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autoboot = 1;
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readfile(PATH_CONFIG, cmd, sizeof(cmd));
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if (*cmd) {
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printf("%s: %s", PATH_CONFIG, cmd);
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if (parse(cmd))
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autoboot = 0;
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/* Do not process this command twice */
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*cmd = 0;
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}
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/*
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* Try to exec stage 3 boot loader. If interrupted by a keypress,
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* or in case of failure, try to load a kernel directly instead.
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*/
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if (autoboot && !*kname) {
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memcpy(kname, PATH_BOOT3, sizeof(PATH_BOOT3));
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if (!keyhit(3*SECOND)) {
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load(kname);
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memcpy(kname, PATH_KERNEL, sizeof(PATH_KERNEL));
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}
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}
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/* Present the user with the boot2 prompt. */
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for (;;) {
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printf(" \n>> FreeBSD/i386 BOOT\n"
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"Default: %u:%s(%u,%c)%s\n"
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"boot: ",
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dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
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'a' + dsk.part, kname);
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if (ioctrl & IO_SERIAL)
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sio_flush();
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if (!autoboot || keyhit(5*SECOND))
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getstr(cmd, sizeof(cmd));
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else
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putchar('\n');
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autoboot = 0;
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if (parse(cmd))
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putchar('\a');
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else
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load(kname);
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}
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}
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/* XXX - Needed for btxld to link the boot2 binary; do not remove. */
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void
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exit(int x)
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{
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}
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static void
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load(const char *fname)
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{
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union {
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struct exec ex;
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Elf32_Ehdr eh;
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} hdr;
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Elf32_Phdr ep[2];
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Elf32_Shdr es[2];
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caddr_t p;
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ino_t ino;
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uint32_t addr, x;
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int fmt, i, j;
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if (!(ino = lookup(fname))) {
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if (!ls)
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printf("No %s\n", fname);
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return;
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}
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if (xfsread(ino, &hdr, sizeof(hdr)))
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return;
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if (N_GETMAGIC(hdr.ex) == ZMAGIC)
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fmt = 0;
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else if (IS_ELF(hdr.eh))
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fmt = 1;
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else {
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printf("Invalid %s\n", "format");
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return;
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}
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if (fmt == 0) {
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addr = hdr.ex.a_entry & 0xffffff;
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p = PTOV(addr);
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fs_off = PAGE_SIZE;
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if (xfsread(ino, p, hdr.ex.a_text))
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return;
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p += roundup2(hdr.ex.a_text, PAGE_SIZE);
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if (xfsread(ino, p, hdr.ex.a_data))
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return;
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p += hdr.ex.a_data + roundup2(hdr.ex.a_bss, PAGE_SIZE);
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bootinfo.bi_symtab = VTOP(p);
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memcpy(p, &hdr.ex.a_syms, sizeof(hdr.ex.a_syms));
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p += sizeof(hdr.ex.a_syms);
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if (hdr.ex.a_syms) {
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if (xfsread(ino, p, hdr.ex.a_syms))
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return;
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p += hdr.ex.a_syms;
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if (xfsread(ino, p, sizeof(int)))
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return;
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x = *(uint32_t *)p;
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p += sizeof(int);
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x -= sizeof(int);
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if (xfsread(ino, p, x))
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return;
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p += x;
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}
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} else {
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fs_off = hdr.eh.e_phoff;
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for (j = i = 0; i < hdr.eh.e_phnum && j < 2; i++) {
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if (xfsread(ino, ep + j, sizeof(ep[0])))
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return;
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if (ep[j].p_type == PT_LOAD)
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j++;
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}
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for (i = 0; i < 2; i++) {
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p = PTOV(ep[i].p_paddr & 0xffffff);
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fs_off = ep[i].p_offset;
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if (xfsread(ino, p, ep[i].p_filesz))
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return;
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}
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p += roundup2(ep[1].p_memsz, PAGE_SIZE);
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bootinfo.bi_symtab = VTOP(p);
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if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
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fs_off = hdr.eh.e_shoff + sizeof(es[0]) *
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(hdr.eh.e_shstrndx + 1);
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if (xfsread(ino, &es, sizeof(es)))
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return;
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for (i = 0; i < 2; i++) {
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memcpy(p, &es[i].sh_size, sizeof(es[i].sh_size));
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p += sizeof(es[i].sh_size);
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fs_off = es[i].sh_offset;
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if (xfsread(ino, p, es[i].sh_size))
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return;
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p += es[i].sh_size;
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}
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}
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addr = hdr.eh.e_entry & 0xffffff;
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}
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bootinfo.bi_esymtab = VTOP(p);
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bootinfo.bi_kernelname = VTOP(fname);
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bootinfo.bi_bios_dev = dsk.drive;
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__exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
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MAKEBOOTDEV(dev_maj[dsk.type], 0, dsk.slice, dsk.unit, dsk.part),
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0, 0, 0, VTOP(&bootinfo));
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}
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static int
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parse(char *arg)
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{
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char *p, *q;
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int drv, c, i;
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while ((c = *arg++)) {
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if (c == ' ' || c == '\t' || c == '\n')
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continue;
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for (p = arg; *p && *p != '\n' && *p != ' ' && *p != '\t'; p++);
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if (*p)
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*p++ = 0;
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if (c == '-') {
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while ((c = *arg++)) {
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for (i = 0; c != optstr[i]; i++)
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if (i == NOPT - 1)
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return -1;
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opts ^= 1 << flags[i];
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}
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if (opts & 1 << RBX_PROBEKBD) {
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i = *(uint8_t *)PTOV(0x496) & 0x10;
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printf("Keyboard: %s\n", i ? "yes" : "no");
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if (!i)
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opts |= 1 << RBX_DUAL | 1 << RBX_SERIAL;
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opts &= ~(1 << RBX_PROBEKBD);
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}
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ioctrl = opts & 1 << RBX_DUAL ? (IO_SERIAL|IO_KEYBOARD) :
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opts & 1 << RBX_SERIAL ? IO_SERIAL : IO_KEYBOARD;
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if (ioctrl & IO_SERIAL)
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sio_init();
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} else {
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for (q = arg--; *q && *q != '('; q++);
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if (*q) {
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drv = -1;
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if (arg[1] == ':') {
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if (*arg < '0' || *arg > '9')
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return -1;
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drv = *arg - '0';
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arg += 2;
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}
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if (q - arg != 2)
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return -1;
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for (i = 0; arg[0] != dev_nm[i][0] ||
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arg[1] != dev_nm[i][1]; i++)
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if (i == NDEV - 1)
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return -1;
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dsk.type = i;
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arg += 3;
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if (arg[1] != ',' || *arg < '0' || *arg > '9')
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return -1;
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dsk.unit = *arg - '0';
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arg += 2;
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dsk.slice = WHOLE_DISK_SLICE;
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if (arg[1] == ',') {
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if (*arg < '0' || *arg > '0' + NDOSPART)
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return -1;
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if ((dsk.slice = *arg - '0'))
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dsk.slice++;
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arg += 2;
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}
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if (arg[1] != ')' || *arg < 'a' || *arg > 'p')
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return -1;
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dsk.part = *arg - 'a';
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arg += 2;
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if (drv == -1)
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drv = dsk.unit;
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dsk.drive = (dsk.type == TYPE_WD ||
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dsk.type == TYPE_AD ||
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dsk.type == TYPE_DA ? DRV_HARD : 0) + drv;
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dsk_meta = 0;
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fsread(0, NULL, 0);
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}
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if ((i = p - arg - !*(p - 1))) {
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if (i >= sizeof(kname))
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return -1;
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memcpy(kname, arg, i + 1);
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}
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}
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arg = p;
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}
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return 0;
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}
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static int
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xfsread(ino_t inode, void *buf, size_t nbyte)
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{
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if (fsread(inode, buf, nbyte) != nbyte) {
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printf("Invalid %s\n", "format");
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return -1;
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}
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return 0;
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}
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static int
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dskread(void *buf, unsigned lba, unsigned nblk)
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{
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struct dos_partition *dp;
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struct disklabel *d;
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char *sec;
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unsigned sl, i;
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if (!dsk_meta) {
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sec = dmadat->secbuf;
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dsk.start = 0;
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if (drvread(sec, DOSBBSECTOR, 1))
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return -1;
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dp = (void *)(sec + DOSPARTOFF);
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sl = dsk.slice;
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if (sl < BASE_SLICE) {
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for (i = 0; i < NDOSPART; i++)
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if (dp[i].dp_typ == DOSPTYP_386BSD &&
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(dp[i].dp_flag & 0x80 || sl < BASE_SLICE)) {
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sl = BASE_SLICE + i;
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if (dp[i].dp_flag & 0x80 ||
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dsk.slice == COMPATIBILITY_SLICE)
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break;
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}
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if (dsk.slice == WHOLE_DISK_SLICE)
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dsk.slice = sl;
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}
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if (sl != WHOLE_DISK_SLICE) {
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if (sl != COMPATIBILITY_SLICE)
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dp += sl - BASE_SLICE;
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if (dp->dp_typ != DOSPTYP_386BSD) {
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printf("Invalid %s\n", "slice");
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return -1;
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}
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dsk.start = dp->dp_start;
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}
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if (drvread(sec, dsk.start + LABELSECTOR, 1))
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return -1;
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d = (void *)(sec + LABELOFFSET);
|
|
if (d->d_magic != DISKMAGIC || d->d_magic2 != DISKMAGIC) {
|
|
if (dsk.part != RAW_PART) {
|
|
printf("Invalid %s\n", "label");
|
|
return -1;
|
|
}
|
|
} else {
|
|
if (!dsk.init) {
|
|
if (d->d_type == DTYPE_SCSI)
|
|
dsk.type = TYPE_DA;
|
|
dsk.init++;
|
|
}
|
|
if (dsk.part >= d->d_npartitions ||
|
|
!d->d_partitions[dsk.part].p_size) {
|
|
printf("Invalid %s\n", "partition");
|
|
return -1;
|
|
}
|
|
dsk.start = d->d_partitions[dsk.part].p_offset;
|
|
}
|
|
}
|
|
return drvread(buf, dsk.start + lba, nblk);
|
|
}
|
|
|
|
static int
|
|
printf(const char *fmt,...)
|
|
{
|
|
static const char digits[16] = "0123456789abcdef";
|
|
va_list ap;
|
|
char buf[10];
|
|
char *s;
|
|
unsigned r, u;
|
|
int c;
|
|
|
|
va_start(ap, fmt);
|
|
while ((c = *fmt++)) {
|
|
if (c == '%') {
|
|
c = *fmt++;
|
|
switch (c) {
|
|
case 'c':
|
|
putchar(va_arg(ap, int));
|
|
continue;
|
|
case 's':
|
|
for (s = va_arg(ap, char *); *s; s++)
|
|
putchar(*s);
|
|
continue;
|
|
case 'u':
|
|
case 'x':
|
|
r = c == 'u' ? 10U : 16U;
|
|
u = va_arg(ap, unsigned);
|
|
s = buf;
|
|
do
|
|
*s++ = digits[u % r];
|
|
while (u /= r);
|
|
while (--s >= buf)
|
|
putchar(*s);
|
|
continue;
|
|
}
|
|
}
|
|
putchar(c);
|
|
}
|
|
va_end(ap);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
putchar(int c)
|
|
{
|
|
if (c == '\n')
|
|
xputc('\r');
|
|
return xputc(c);
|
|
}
|
|
|
|
static uint32_t
|
|
memsize(int type)
|
|
{
|
|
v86.addr = type;
|
|
v86.eax = 0x8800;
|
|
v86int();
|
|
return v86.eax;
|
|
}
|
|
|
|
static int
|
|
drvread(void *buf, unsigned lba, unsigned nblk)
|
|
{
|
|
static unsigned c = 0x2d5c7c2f;
|
|
|
|
printf("%c\b", c = c << 8 | c >> 24);
|
|
v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
|
|
v86.addr = XREADORG; /* call to xread in boot1 */
|
|
v86.es = VTOPSEG(buf);
|
|
v86.eax = lba;
|
|
v86.ebx = VTOPOFF(buf);
|
|
v86.ecx = lba >> 16;
|
|
v86.edx = nblk << 8 | dsk.drive;
|
|
v86int();
|
|
v86.ctl = V86_FLAGS;
|
|
if (V86_CY(v86.efl)) {
|
|
printf("Disk error 0x%x (lba=0x%x)\n", v86.eax >> 8 & 0xff,
|
|
lba);
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
keyhit(unsigned ticks)
|
|
{
|
|
uint32_t t0, t1;
|
|
|
|
if (opts & 1 << RBX_NOINTR)
|
|
return 0;
|
|
t0 = 0;
|
|
for (;;) {
|
|
if (xgetc(1))
|
|
return 1;
|
|
t1 = *(uint32_t *)PTOV(0x46c);
|
|
if (!t0)
|
|
t0 = t1;
|
|
if (t1 < t0 || t1 >= t0 + ticks)
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static int
|
|
xputc(int c)
|
|
{
|
|
if (ioctrl & IO_KEYBOARD)
|
|
putc(c);
|
|
if (ioctrl & IO_SERIAL)
|
|
sio_putc(c);
|
|
return c;
|
|
}
|
|
|
|
static int
|
|
xgetc(int fn)
|
|
{
|
|
if (opts & 1 << RBX_NOINTR)
|
|
return 0;
|
|
for (;;) {
|
|
if (ioctrl & IO_KEYBOARD && getc(1))
|
|
return fn ? 1 : getc(0);
|
|
if (ioctrl & IO_SERIAL && sio_ischar())
|
|
return fn ? 1 : sio_getc();
|
|
if (fn)
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static int
|
|
getc(int fn)
|
|
{
|
|
v86.addr = 0x16;
|
|
v86.eax = fn << 8;
|
|
v86int();
|
|
return fn == 0 ? v86.eax & 0xff : !V86_ZR(v86.efl);
|
|
}
|