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/*
* Copyright (c) 1998 Robert Nordier
* All rights reserved.
*
* Redistribution and use in source and binary forms are freely
* permitted provided that the above copyright notice and this
* paragraph and the following disclaimer are duplicated in all
* such forms.
*
* This software is provided "AS IS" and without any express or
* implied warranties, including, without limitation, the implied
* warranties of merchantability and fitness for a particular
* purpose.
*/
/*
* $Id: boot2.c,v 1.15 1998/11/08 18:29:29 rnordier Exp $
*/
#include <sys/param.h>
#include <sys/reboot.h>
#include <sys/diskslice.h>
#include <sys/disklabel.h>
#include <sys/dirent.h>
#include <machine/bootinfo.h>
#include <ufs/ffs/fs.h>
#include <ufs/ufs/dinode.h>
#include <stdarg.h>
#include <a.out.h>
#include <elf.h>
#include <btxv86.h>
#include "lib.h"
#define RBX_ASKNAME 0x0 /* -a */
#define RBX_SINGLE 0x1 /* -s */
#define RBX_DFLTROOT 0x5 /* -r */
#define RBX_KDB 0x6 /* -d */
#define RBX_CONFIG 0xa /* -c */
#define RBX_VERBOSE 0xb /* -v */
#define RBX_SERIAL 0xc /* -h */
#define RBX_CDROM 0xd /* -C */
#define RBX_GDB 0xf /* -g */
#define RBX_DUAL 0x1d /* -D */
#define RBX_PROBEKBD 0x1e /* -P */
#define RBX_MASK 0xffff
#define PATH_CONFIG "/boot.config"
#define PATH_BOOT3 "/boot/loader"
#define PATH_KERNEL "/kernel"
#define PATH_HELP "boot.help"
#define ARGS 0x800
#define NOPT 11
#define BSIZEMAX 8192
#define NDEV 5
#define MEM_BASE 0x12
#define MEM_EXT 0x15
#define V86_CY(x) ((x) & 1)
#define V86_ZR(x) ((x) & 0x40)
#define DRV_HARD 0x80
#define DRV_MASK 0x7f
#define MAJ_WD 0
#define MAJ_WFD 1
#define MAJ_FD 2
#define MAJ_DA 4
extern uint32_t _end;
static const char optstr[NOPT] = "DhaCcdgPrsv";
static const unsigned char flags[NOPT] = {
RBX_DUAL,
RBX_SERIAL,
RBX_ASKNAME,
RBX_CDROM,
RBX_CONFIG,
RBX_KDB,
RBX_GDB,
RBX_PROBEKBD,
RBX_DFLTROOT,
RBX_SINGLE,
RBX_VERBOSE
};
static const char *const dev_nm[] = {"wd", " ", "fd", " ", "da"};
static struct dsk {
unsigned drive;
unsigned type;
unsigned unit;
unsigned slice;
unsigned part;
unsigned start;
int init;
int meta;
} dsk;
static char cmd[512];
static char kname[1024];
static char help[2048];
static uint32_t opts;
static struct bootinfo bootinfo;
static int ls;
static uint32_t fs_off;
static uint8_t ioctrl = 0x1;
void exit(int);
static void load(const char *);
static int parse(char *);
static void readfile(const char *, void *, size_t);
static ino_t lookup(const char *);
static int fsfind(const char *, ino_t *);
static int xfsread(ino_t, void *, size_t);
static ssize_t fsread(ino_t, void *, size_t);
static int dskread(void *, unsigned, unsigned);
static int printf(const char *,...);
static void getstr(char *, int);
static int putchar(int);
static int getchar(void);
static void *memcpy(void *, const void *, size_t);
static int strcmp(const char *, const char *);
static void *malloc(size_t);
static uint32_t memsize(int);
static uint32_t drvinfo(int);
static int drvread(void *, unsigned, unsigned);
static int keyhit(unsigned);
static int xputc(int);
static int xgetc(int);
static void putc(int);
static int getc(int);
int
main(void)
{
int autoboot, helpon, i;
v86.ctl = V86_FLAGS;
dsk.drive = *(uint8_t *)PTOV(ARGS);
dsk.type = dsk.drive & DRV_HARD ? MAJ_WD : MAJ_FD;
dsk.unit = dsk.drive & DRV_MASK;
dsk.slice = *(uint8_t *)PTOV(ARGS + 1) + 1;
bootinfo.bi_version = BOOTINFO_VERSION;
bootinfo.bi_size = sizeof(bootinfo);
bootinfo.bi_basemem = memsize(MEM_BASE);
bootinfo.bi_extmem = memsize(MEM_EXT);
bootinfo.bi_memsizes_valid++;
for (i = 0; i < N_BIOS_GEOM; i++)
bootinfo.bi_bios_geom[i] = drvinfo(i);
autoboot = 2;
helpon = 1;
readfile(PATH_HELP, help, sizeof(help));
readfile(PATH_CONFIG, cmd, sizeof(cmd));
if (*cmd) {
printf("%s: %s", PATH_CONFIG, cmd);
if (parse(cmd))
autoboot = 0;
*cmd = 0;
}
if (autoboot && !*kname) {
if (autoboot == 2) {
memcpy(kname, PATH_BOOT3, sizeof(PATH_BOOT3));
if (!keyhit(0x37)) {
load(kname);
autoboot = 1;
}
}
if (autoboot == 1)
memcpy(kname, PATH_KERNEL, sizeof(PATH_KERNEL));
}
for (;;) {
printf(" \n>> FreeBSD/i386 BOOT\n"
"Default: %u:%s(%u,%c)%s\n"
"%s"
"boot: ",
dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
'a' + dsk.part, kname, helpon ? help : "");
if (ioctrl & 0x2)
sio_flush();
if (!autoboot || keyhit(0x5a))
getstr(cmd, sizeof(cmd));
else
putchar('\n');
autoboot = helpon = 0;
if (parse(cmd))
helpon = 1;
else
load(kname);
}
}
void
exit(int x)
{
}
static void
load(const char *fname)
{
union {
struct exec ex;
Elf32_Ehdr eh;
} hdr;
Elf32_Phdr ep[2];
Elf32_Shdr es[2];
caddr_t p;
ino_t ino;
uint32_t addr, x;
int fmt, i, j;
if (!(ino = lookup(fname))) {
if (!ls)
printf("No %s\n", fname);
return;
}
if (xfsread(ino, &hdr, sizeof(hdr)))
return;
if (N_GETMAGIC(hdr.ex) == ZMAGIC)
fmt = 0;
else if (IS_ELF(hdr.eh))
fmt = 1;
else {
printf("Invalid %s\n", "format");
return;
}
if (fmt == 0) {
addr = hdr.ex.a_entry & 0xffffff;
p = PTOV(addr);
fs_off = PAGE_SIZE;
if (xfsread(ino, p, hdr.ex.a_text))
return;
p += roundup2(hdr.ex.a_text, PAGE_SIZE);
if (xfsread(ino, p, hdr.ex.a_data))
return;
p += hdr.ex.a_data + roundup2(hdr.ex.a_bss, PAGE_SIZE);
bootinfo.bi_symtab = VTOP(p);
memcpy(p, &hdr.ex.a_syms, sizeof(hdr.ex.a_syms));
p += sizeof(hdr.ex.a_syms);
if (hdr.ex.a_syms) {
if (xfsread(ino, p, hdr.ex.a_syms))
return;
p += hdr.ex.a_syms;
if (xfsread(ino, p, sizeof(int)))
return;
x = *(uint32_t *)p;
p += sizeof(int);
x -= sizeof(int);
if (xfsread(ino, p, x))
return;
p += x;
}
} else {
fs_off = hdr.eh.e_phoff;
for (j = i = 0; i < hdr.eh.e_phoff && j < 2; i++) {
if (xfsread(ino, ep + j, sizeof(ep[0])))
return;
if (ep[j].p_type == PT_LOAD)
j++;
}
for (i = 0; i < 2; i++) {
p = PTOV(ep[i].p_paddr & 0xffffff);
fs_off = ep[i].p_offset;
if (xfsread(ino, p, ep[i].p_filesz))
return;
}
p += roundup2(ep[1].p_memsz, PAGE_SIZE);
bootinfo.bi_symtab = VTOP(p);
if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
fs_off = hdr.eh.e_shoff + sizeof(es[0]) *
(hdr.eh.e_shstrndx + 1);
if (xfsread(ino, &es, sizeof(es)))
return;
for (i = 0; i < 2; i++) {
memcpy(p, &es[i].sh_size, sizeof(es[i].sh_size));
p += sizeof(es[i].sh_size);
fs_off = es[i].sh_offset;
if (xfsread(ino, p, es[i].sh_size))
return;
p += es[i].sh_size;
}
}
addr = hdr.eh.e_entry & 0xffffff;
}
bootinfo.bi_esymtab = VTOP(p);
bootinfo.bi_kernelname = VTOP(fname);
__exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
MAKEBOOTDEV(dsk.type, 0, dsk.slice, dsk.unit, dsk.part),
0, 0, 0, VTOP(&bootinfo));
}
static int
parse(char *arg)
{
char *p, *q;
int drv, c, i;
while ((c = *arg++)) {
if (c == ' ')
continue;
for (p = arg; *p && *p != '\n' && *p != ' '; p++);
if (*p)
*p++ = 0;
if (c == '-') {
while ((c = *arg++)) {
for (i = 0; c != optstr[i]; i++)
if (i == NOPT - 1)
return -1;
opts ^= 1 << flags[i];
}
if (opts & 1 << RBX_PROBEKBD) {
i = *(uint8_t *)PTOV(0x496) & 0x10;
printf("Keyboard: %s\n", i ? "yes" : "no");
if (!i)
opts |= 1 << RBX_DUAL | 1 << RBX_SERIAL;
opts &= ~(1 << RBX_PROBEKBD);
}
ioctrl = opts & 1 << RBX_DUAL ? 0x3 :
opts & 1 << RBX_SERIAL ? 0x2 : 0x1;
if (ioctrl & 0x2)
sio_init();
} else {
for (q = arg--; *q && *q != '('; q++);
if (*q) {
drv = -1;
if (arg[1] == ':') {
if (*arg < '0' || *arg > '9')
return -1;
drv = *arg - '0';
arg += 2;
}
if (q - arg != 2)
return -1;
for (i = 0; arg[0] != dev_nm[i][0] ||
arg[1] != dev_nm[i][1]; i++)
if (i == NDEV - 1)
return -1;
dsk.type = i;
arg += 3;
if (arg[1] != ',' || *arg < '0' || *arg > '9')
return -1;
dsk.unit = *arg - '0';
arg += 2;
dsk.slice = WHOLE_DISK_SLICE;
if (arg[1] == ',') {
if (*arg < '0' || *arg > '0' + NDOSPART)
return -1;
if ((dsk.slice = *arg - '0'))
dsk.slice++;
arg += 2;
}
if (arg[1] != ')' || *arg < 'a' || *arg > 'p')
return -1;
dsk.part = *arg - 'a';
arg += 2;
if (drv == -1)
drv = dsk.unit;
dsk.drive = (dsk.type == MAJ_WD ||
dsk.type == MAJ_DA ? DRV_HARD : 0) + drv;
dsk.meta = 0;
fsread(0, NULL, 0);
}
if ((i = p - arg - !*(p - 1))) {
if (i >= sizeof(kname))
return -1;
memcpy(kname, arg, i + 1);
}
}
arg = p;
}
return 0;
}
static void
readfile(const char *fname, void *buf, size_t size)
{
ino_t ino;
if ((ino = lookup(fname)))
fsread(ino, buf, size);
}
static ino_t
lookup(const char *path)
{
char name[MAXNAMLEN + 1];
const char *s;
ino_t ino;
ssize_t n;
int dt;
ino = ROOTINO;
dt = DT_DIR;
for (;;) {
if (*path == '/')
path++;
if (!*path)
break;
for (s = path; *s && *s != '/'; s++);
if ((n = s - path) > MAXNAMLEN)
return 0;
ls = *path == '?' && n == 1 && !*s;
memcpy(name, path, n);
name[n] = 0;
if ((dt = fsfind(name, &ino)) <= 0)
break;
path = s;
}
return dt == DT_REG ? ino : 0;
}
static int
fsfind(const char *name, ino_t * ino)
{
char buf[DEV_BSIZE];
struct dirent *d;
char *s;
ssize_t n;
fs_off = 0;
while ((n = fsread(*ino, buf, DEV_BSIZE)) > 0)
for (s = buf; s < buf + DEV_BSIZE;) {
d = (void *)s;
if (ls)
printf("%s ", d->d_name);
else if (!strcmp(name, d->d_name)) {
*ino = d->d_fileno;
return d->d_type;
}
s += d->d_reclen;
}
if (n != -1 && ls)
putchar('\n');
return 0;
}
static int
xfsread(ino_t inode, void *buf, size_t nbyte)
{
if (fsread(inode, buf, nbyte) != nbyte) {
printf("Invalid %s\n", "format");
return -1;
}
return 0;
}
static ssize_t
fsread(ino_t inode, void *buf, size_t nbyte)
{
static struct fs fs;
static struct dinode din;
static char *blkbuf;
static ufs_daddr_t *indbuf;
static ino_t inomap;
static ufs_daddr_t blkmap, indmap;
static unsigned fsblks;
char *s;
ufs_daddr_t lbn, addr;
size_t n, nb, off;
if (!dsk.meta) {
if (!blkbuf)
blkbuf = malloc(BSIZEMAX);
inomap = 0;
if (dskread(blkbuf, SBOFF / DEV_BSIZE, SBSIZE / DEV_BSIZE))
return -1;
memcpy(&fs, blkbuf, sizeof(fs));
if (fs.fs_magic != FS_MAGIC) {
printf("Not ufs\n");
return -1;
}
fsblks = fs.fs_bsize >> DEV_BSHIFT;
dsk.meta++;
}
if (!inode)
return 0;
if (inomap != inode) {
if (dskread(blkbuf, fsbtodb(&fs, ino_to_fsba(&fs, inode)),
fsblks))
return -1;
din = ((struct dinode *)blkbuf)[inode % INOPB(&fs)];
inomap = inode;
fs_off = 0;
blkmap = indmap = 0;
}
s = buf;
if (nbyte > (n = din.di_size - fs_off))
nbyte = n;
nb = nbyte;
while (nb) {
lbn = lblkno(&fs, fs_off);
if (lbn < NDADDR)
addr = din.di_db[lbn];
else {
if (indmap != din.di_ib[0]) {
if (!indbuf)
indbuf = malloc(BSIZEMAX);
if (dskread(indbuf, fsbtodb(&fs, din.di_ib[0]),
fsblks))
return -1;
indmap = din.di_ib[0];
}
addr = indbuf[(lbn - NDADDR) % NINDIR(&fs)];
}
n = dblksize(&fs, &din, lbn);
if (blkmap != addr) {
if (dskread(blkbuf, fsbtodb(&fs, addr), n >> DEV_BSHIFT))
return -1;
blkmap = addr;
}
off = blkoff(&fs, fs_off);
n -= off;
if (n > nb)
n = nb;
memcpy(s, blkbuf + off, n);
s += n;
fs_off += n;
nb -= n;
}
return nbyte;
}
static int
dskread(void *buf, unsigned lba, unsigned nblk)
{
static char *sec;
struct dos_partition *dp;
struct disklabel *d;
unsigned sl, i;
if (!dsk.meta) {
if (!sec)
sec = malloc(DEV_BSIZE);
dsk.start = 0;
if (drvread(sec, DOSBBSECTOR, 1))
return -1;
dp = (void *)(sec + DOSPARTOFF);
sl = dsk.slice;
if (sl < BASE_SLICE) {
for (i = 0; i < NDOSPART; i++)
if (dp[i].dp_typ == DOSPTYP_386BSD &&
(dp[i].dp_flag & 0x80 || sl < BASE_SLICE)) {
sl = BASE_SLICE + i;
if (dp[i].dp_flag & 0x80 ||
dsk.slice == COMPATIBILITY_SLICE)
break;
}
if (dsk.slice == WHOLE_DISK_SLICE)
dsk.slice = sl;
}
if (sl != WHOLE_DISK_SLICE) {
if (sl != COMPATIBILITY_SLICE)
dp += sl - BASE_SLICE;
if (dp->dp_typ != DOSPTYP_386BSD) {
printf("Invalid %s\n", "slice");
return -1;
}
dsk.start = dp->dp_start;
}
if (drvread(sec, dsk.start + LABELSECTOR, 1))
return -1;
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 = MAJ_DA;
dsk.init++;
}
if (dsk.part >= d->d_npartitions) {
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 void
getstr(char *str, int size)
{
char *s;
int c;
s = str;
do {
switch (c = getchar()) {
case 0:
break;
case '\b':
if (s > str) {
s--;
putchar(c);
putchar(' ');
} else
c = 0;
break;
case '\n':
*s = 0;
break;
default:
if (s - str < size - 1)
*s++ = c;
}
if (c)
putchar(c);
} while (c != '\n');
}
static int
putchar(int c)
{
if (c == '\n')
xputc('\r');
return xputc(c);
}
static int
getchar(void)
{
int c;
c = xgetc(0);
if (c == '\r')
c = '\n';
return c;
}
static void *
memcpy(void *dst, const void *src, size_t size)
{
const char *s;
char *d;
for (d = dst, s = src; size; size--)
*d++ = *s++;
return dst;
}
static int
strcmp(const char *s1, const char *s2)
{
for (; *s1 == *s2 && *s1; s1++, s2++);
return (u_char)*s1 - (u_char)*s2;
}
static void *
malloc(size_t size)
{
static uint32_t next;
void *p;
if (!next)
next = roundup2(__base + _end, 0x10000) - __base;
p = (void *)next;
next += size;
return p;
}
static uint32_t
memsize(int type)
{
v86.addr = type;
v86.eax = 0x8800;
v86int();
return v86.eax;
}
static uint32_t
drvinfo(int drive)
{
v86.addr = 0x13;
v86.eax = 0x800;
v86.edx = DRV_HARD + drive;
v86int();
if (V86_CY(v86.efl))
return 0x4f010f;
return ((v86.ecx & 0xc0) << 18) | ((v86.ecx & 0xff00) << 8) |
(v86.edx & 0xff00) | (v86.ecx & 0x3f);
}
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 = 0x604;
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;
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 & 0x1)
putc(c);
if (ioctrl & 0x2)
sio_putc(c);
return c;
}
static int
xgetc(int fn)
{
for (;;) {
if (ioctrl & 0x1 && getc(1))
return fn ? 1 : getc(0);
if (ioctrl & 0x2 && sio_ischar())
return fn ? 1 : sio_getc();
if (fn)
return 0;
}
}
static void
putc(int c)
{
v86.addr = 0x10;
v86.eax = 0xe00 | (c & 0xff);
v86.ebx = 0x7;
v86int();
}
static int
getc(int fn)
{
v86.addr = 0x16;
v86.eax = fn << 8;
v86int();
return fn == 0 ? v86.eax & 0xff : !V86_ZR(v86.efl);
}
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