freebsd-dev/sys/boot/i386/libi386/bootinfo32.c
Peter Wemm 48a0b96a50 Enable the i386 loader to load and run an amd64 kernel. If this puts
things over floppy size limits, I can exclude it for release builds or
something like that.  Most of the changes are to get the load_elf.c file
into a seperate elf32_ or elf64_ namespace so that you can have two
ELF loaders present at once.  Note that for 64 bit kernels, it actually
starts up the kernel already in 64 bit mode with paging enabled.  This
is really easy because we have a known minimum feature set.

Of note is that for amd64, we have to pass in the bios int 15 0xe821
memory map because once in long mode, you absolutely cannot make VM86
calls.  amd64 does not use 'struct bootinfo' at all.  It is a pure loader
metadata startup, just like sparc64 and powerpc.  Much of the
infrastructure to support this was adapted from sparc64.
2003-05-01 03:56:30 +00:00

273 lines
8.5 KiB
C

/*-
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* 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.
*
* $FreeBSD$
*/
#include <stand.h>
#include <sys/param.h>
#include <sys/reboot.h>
#include <sys/linker.h>
#include <machine/bootinfo.h>
#include "bootstrap.h"
#include "libi386.h"
#include "btxv86.h"
static struct bootinfo bi;
/*
* Copy module-related data into the load area, where it can be
* used as a directory for loaded modules.
*
* Module data is presented in a self-describing format. Each datum
* is preceded by a 32-bit identifier and a 32-bit size field.
*
* Currently, the following data are saved:
*
* MOD_NAME (variable) module name (string)
* MOD_TYPE (variable) module type (string)
* MOD_ARGS (variable) module parameters (string)
* MOD_ADDR sizeof(vm_offset_t) module load address
* MOD_SIZE sizeof(size_t) module size
* MOD_METADATA (variable) type-specific metadata
*/
#define COPY32(v, a, c) { \
u_int32_t x = (v); \
if (c) \
i386_copyin(&x, a, sizeof(x)); \
a += sizeof(x); \
}
#define MOD_STR(t, a, s, c) { \
COPY32(t, a, c); \
COPY32(strlen(s) + 1, a, c); \
if (c) \
i386_copyin(s, a, strlen(s) + 1); \
a += roundup(strlen(s) + 1, sizeof(u_long));\
}
#define MOD_NAME(a, s, c) MOD_STR(MODINFO_NAME, a, s, c)
#define MOD_TYPE(a, s, c) MOD_STR(MODINFO_TYPE, a, s, c)
#define MOD_ARGS(a, s, c) MOD_STR(MODINFO_ARGS, a, s, c)
#define MOD_VAR(t, a, s, c) { \
COPY32(t, a, c); \
COPY32(sizeof(s), a, c); \
if (c) \
i386_copyin(&s, a, sizeof(s)); \
a += roundup(sizeof(s), sizeof(u_long)); \
}
#define MOD_ADDR(a, s, c) MOD_VAR(MODINFO_ADDR, a, s, c)
#define MOD_SIZE(a, s, c) MOD_VAR(MODINFO_SIZE, a, s, c)
#define MOD_METADATA(a, mm, c) { \
COPY32(MODINFO_METADATA | mm->md_type, a, c); \
COPY32(mm->md_size, a, c); \
if (c) \
i386_copyin(mm->md_data, a, mm->md_size); \
a += roundup(mm->md_size, sizeof(u_long));\
}
#define MOD_END(a, c) { \
COPY32(MODINFO_END, a, c); \
COPY32(0, a, c); \
}
static vm_offset_t
bi_copymodules32(vm_offset_t addr)
{
struct preloaded_file *fp;
struct file_metadata *md;
int c;
c = addr != 0;
/* start with the first module on the list, should be the kernel */
for (fp = file_findfile(NULL, NULL); fp != NULL; fp = fp->f_next) {
MOD_NAME(addr, fp->f_name, c); /* this field must come first */
MOD_TYPE(addr, fp->f_type, c);
if (fp->f_args)
MOD_ARGS(addr, fp->f_args, c);
MOD_ADDR(addr, fp->f_addr, c);
MOD_SIZE(addr, fp->f_size, c);
for (md = fp->f_metadata; md != NULL; md = md->md_next)
if (!(md->md_type & MODINFOMD_NOCOPY))
MOD_METADATA(addr, md, c);
}
MOD_END(addr, c);
return(addr);
}
/*
* Load the information expected by an i386 kernel.
*
* - The 'boothowto' argument is constructed
* - The 'bootdev' argument is constructed
* - The 'bootinfo' struct is constructed, and copied into the kernel space.
* - The kernel environment is copied into kernel space.
* - Module metadata are formatted and placed in kernel space.
*/
int
bi_load32(char *args, int *howtop, int *bootdevp, vm_offset_t *bip, vm_offset_t *modulep, vm_offset_t *kernendp)
{
struct preloaded_file *xp, *kfp;
struct i386_devdesc *rootdev;
struct file_metadata *md;
vm_offset_t addr;
vm_offset_t kernend;
vm_offset_t envp;
vm_offset_t size;
vm_offset_t ssym, esym;
char *rootdevname;
int bootdevnr, i, howto;
char *kernelname;
const char *kernelpath;
howto = bi_getboothowto(args);
/*
* Allow the environment variable 'rootdev' to override the supplied device
* This should perhaps go to MI code and/or have $rootdev tested/set by
* MI code before launching the kernel.
*/
rootdevname = getenv("rootdev");
i386_getdev((void **)(&rootdev), rootdevname, NULL);
if (rootdev == NULL) { /* bad $rootdev/$currdev */
printf("can't determine root device\n");
return(EINVAL);
}
/* Try reading the /etc/fstab file to select the root device */
getrootmount(i386_fmtdev((void *)rootdev));
/* Do legacy rootdev guessing */
/* XXX - use a default bootdev of 0. Is this ok??? */
bootdevnr = 0;
switch(rootdev->d_type) {
case DEVT_CD:
/* Pass in BIOS device number. */
bi.bi_bios_dev = bc_unit2bios(rootdev->d_kind.bioscd.unit);
bootdevnr = bc_getdev(rootdev);
break;
case DEVT_DISK:
/* pass in the BIOS device number of the current disk */
bi.bi_bios_dev = bd_unit2bios(rootdev->d_kind.biosdisk.unit);
bootdevnr = bd_getdev(rootdev);
break;
case DEVT_NET:
break;
default:
printf("WARNING - don't know how to boot from device type %d\n", rootdev->d_type);
}
if (bootdevnr == -1) {
printf("root device %s invalid\n", i386_fmtdev(rootdev));
return (EINVAL);
}
free(rootdev);
/* find the last module in the chain */
addr = 0;
for (xp = file_findfile(NULL, NULL); xp != NULL; xp = xp->f_next) {
if (addr < (xp->f_addr + xp->f_size))
addr = xp->f_addr + xp->f_size;
}
/* pad to a page boundary */
addr = roundup(addr, PAGE_SIZE);
/* copy our environment */
envp = addr;
addr = bi_copyenv(addr);
/* pad to a page boundary */
addr = roundup(addr, PAGE_SIZE);
kfp = file_findfile(NULL, "elf64 kernel");
if (kfp == NULL)
kfp = file_findfile(NULL, "elf32 kernel");
if (kfp == NULL)
panic("can't find kernel file");
kernend = 0; /* fill it in later */
file_addmetadata(kfp, MODINFOMD_HOWTO, sizeof howto, &howto);
file_addmetadata(kfp, MODINFOMD_ENVP, sizeof envp, &envp);
file_addmetadata(kfp, MODINFOMD_KERNEND, sizeof kernend, &kernend);
bios_addsmapdata(kfp);
/* Figure out the size and location of the metadata */
*modulep = addr;
size = bi_copymodules32(0);
kernend = roundup(addr + size, PAGE_SIZE);
*kernendp = kernend;
/* patch MODINFOMD_KERNEND */
md = file_findmetadata(kfp, MODINFOMD_KERNEND);
bcopy(&kernend, md->md_data, sizeof kernend);
/* copy module list and metadata */
(void)bi_copymodules32(addr);
ssym = esym = 0;
md = file_findmetadata(kfp, MODINFOMD_SSYM);
if (md != NULL)
ssym = *((vm_offset_t *)&(md->md_data));
md = file_findmetadata(kfp, MODINFOMD_ESYM);
if (md != NULL)
esym = *((vm_offset_t *)&(md->md_data));
if (ssym == 0 || esym == 0)
ssym = esym = 0; /* sanity */
/* legacy bootinfo structure */
kernelname = getenv("kernelname");
i386_getdev(NULL, kernelname, &kernelpath);
bi.bi_version = BOOTINFO_VERSION;
bi.bi_kernelname = 0; /* XXX char * -> kernel name */
bi.bi_nfs_diskless = 0; /* struct nfs_diskless * */
bi.bi_n_bios_used = 0; /* XXX would have to hook biosdisk driver for these */
for (i = 0; i < N_BIOS_GEOM; i++)
bi.bi_bios_geom[i] = bd_getbigeom(i);
bi.bi_size = sizeof(bi);
bi.bi_memsizes_valid = 1;
bi.bi_basemem = bios_basemem / 1024;
bi.bi_extmem = bios_extmem / 1024;
bi.bi_envp = envp;
bi.bi_modulep = *modulep;
bi.bi_kernend = kernend;
bi.bi_kernelname = VTOP(kernelpath);
bi.bi_symtab = ssym; /* XXX this is only the primary kernel symtab */
bi.bi_esymtab = esym;
/* legacy boot arguments */
*howtop = howto | RB_BOOTINFO;
*bootdevp = bootdevnr;
*bip = VTOP(&bi);
return(0);
}