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grub/loader/i386/multiboot.c
Vladimir 'phcoder' Serbinenko 14e43c6e02 First working newreloc
2010-01-10 15:06:17 +01:00

516 lines
13 KiB
C
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/* multiboot.c - boot a multiboot OS image. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 1999,2000,2001,2002,2003,2004,2005,2007,2008,2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* FIXME: The following features from the Multiboot specification still
* need to be implemented:
* - VBE support
* - symbol table
* - drives table
* - ROM configuration table
* - APM table
*/
/* The bits in the required part of flags field we don't support. */
#define UNSUPPORTED_FLAGS 0x0000fff0
#include <grub/loader.h>
#include <grub/machine/loader.h>
#include <grub/multiboot.h>
#include <grub/machine/init.h>
#include <grub/machine/memory.h>
#include <grub/cpu/multiboot.h>
#include <grub/elf.h>
#include <grub/aout.h>
#include <grub/file.h>
#include <grub/err.h>
#include <grub/dl.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/gzio.h>
#include <grub/env.h>
#ifdef GRUB_MACHINE_PCBIOS
#include <grub/machine/biosnum.h>
#include <grub/disk.h>
#include <grub/device.h>
#include <grub/partition.h>
#endif
#include <grub/i386/relocator.h>
extern grub_dl_t my_mod;
static struct multiboot_info *mbi, *mbi_dest;
struct grub_relocator *grub_multiboot_relocator = NULL;
static grub_size_t code_size;
grub_uint32_t grub_multiboot_payload_eip;
static grub_err_t
grub_multiboot_boot (void)
{
struct grub_relocator32_state state =
{
.eax = MULTIBOOT_BOOTLOADER_MAGIC,
.ebx = PTR_TO_UINT32 (mbi_dest),
.ecx = 0,
.edx = 0,
.eip = grub_multiboot_payload_eip,
/* Set esp to some random location in low memory to avoid breaking
non-compliant kernels. */
.esp = 0x7ff00
};
grub_relocator32_boot (grub_multiboot_relocator, state);
/* Not reached. */
return GRUB_ERR_NONE;
}
static grub_err_t
grub_multiboot_unload (void)
{
if (mbi)
{
unsigned int i;
for (i = 0; i < mbi->mods_count; i++)
{
grub_free ((void *)
((struct multiboot_mod_list *) mbi->mods_addr)[i].mod_start);
grub_free ((void *)
((struct multiboot_mod_list *) mbi->mods_addr)[i].cmdline);
}
grub_free ((void *) mbi->mods_addr);
}
grub_relocator_unload (grub_multiboot_relocator);
grub_multiboot_relocator = NULL;
mbi = NULL;
grub_dl_unref (my_mod);
return GRUB_ERR_NONE;
}
/* Return the length of the Multiboot mmap that will be needed to allocate
our platform's map. */
static grub_uint32_t
grub_get_multiboot_mmap_len (void)
{
grub_size_t count = 0;
auto int NESTED_FUNC_ATTR hook (grub_uint64_t, grub_uint64_t, grub_uint32_t);
int NESTED_FUNC_ATTR hook (grub_uint64_t addr __attribute__ ((unused)),
grub_uint64_t size __attribute__ ((unused)),
grub_uint32_t type __attribute__ ((unused)))
{
count++;
return 0;
}
grub_mmap_iterate (hook);
return count * sizeof (struct multiboot_mmap_entry);
}
/* Fill previously allocated Multiboot mmap. */
static void
grub_fill_multiboot_mmap (struct multiboot_mmap_entry *first_entry)
{
struct multiboot_mmap_entry *mmap_entry = (struct multiboot_mmap_entry *) first_entry;
auto int NESTED_FUNC_ATTR hook (grub_uint64_t, grub_uint64_t, grub_uint32_t);
int NESTED_FUNC_ATTR hook (grub_uint64_t addr, grub_uint64_t size, grub_uint32_t type)
{
mmap_entry->addr = addr;
mmap_entry->len = size;
mmap_entry->type = type;
mmap_entry->size = sizeof (struct multiboot_mmap_entry) - sizeof (mmap_entry->size);
mmap_entry++;
return 0;
}
grub_mmap_iterate (hook);
}
#define MULTIBOOT_LOAD_ELF64
#include "multiboot_elfxx.c"
#undef MULTIBOOT_LOAD_ELF64
#define MULTIBOOT_LOAD_ELF32
#include "multiboot_elfxx.c"
#undef MULTIBOOT_LOAD_ELF32
/* Load ELF32 or ELF64. */
static grub_err_t
grub_multiboot_load_elf (grub_file_t file, void *buffer)
{
if (grub_multiboot_is_elf32 (buffer))
return grub_multiboot_load_elf32 (file, buffer);
else if (grub_multiboot_is_elf64 (buffer))
return grub_multiboot_load_elf64 (file, buffer);
return grub_error (GRUB_ERR_UNKNOWN_OS, "unknown ELF class");
}
static int
grub_multiboot_get_bootdev (grub_uint32_t *bootdev)
{
#ifdef GRUB_MACHINE_PCBIOS
char *p;
grub_uint32_t biosdev, slice = ~0, part = ~0;
grub_device_t dev;
biosdev = grub_get_root_biosnumber ();
dev = grub_device_open (0);
if (dev && dev->disk && dev->disk->partition)
{
p = dev->disk->partition->partmap->get_name (dev->disk->partition);
if (p)
{
if ((p[0] >= '0') && (p[0] <= '9'))
{
slice = grub_strtoul (p, &p, 0) - 1;
if ((p) && (p[0] == ','))
p++;
}
if ((p[0] >= 'a') && (p[0] <= 'z'))
part = p[0] - 'a';
}
}
if (dev)
grub_device_close (dev);
*bootdev = ((biosdev & 0xff) << 24) | ((slice & 0xff) << 16)
| ((part & 0xff) << 8) | 0xff;
return (biosdev != ~0UL);
#else
*bootdev = 0xffffffff;
return 0;
#endif
}
void
grub_multiboot (int argc, char *argv[])
{
grub_file_t file = 0;
char buffer[MULTIBOOT_SEARCH], *cmdline = 0, *p;
struct multiboot_header *header;
grub_ssize_t len, cmdline_length, boot_loader_name_length;
grub_uint32_t mmap_length;
int i;
int cmdline_argc;
char **cmdline_argv;
int mbichunk_size;
void *mbichunk;
grub_addr_t mbichunk_dest;
grub_err_t err;
grub_loader_unset ();
if (argc == 0)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, "no kernel specified");
goto fail;
}
file = grub_gzfile_open (argv[0], 1);
if (! file)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, "couldn't open file");
goto fail;
}
len = grub_file_read (file, buffer, MULTIBOOT_SEARCH);
if (len < 32)
{
grub_error (GRUB_ERR_BAD_OS, "file too small");
goto fail;
}
/* Look for the multiboot header in the buffer. The header should
be at least 12 bytes and aligned on a 4-byte boundary. */
for (header = (struct multiboot_header *) buffer;
((char *) header <= buffer + len - 12) || (header = 0);
header = (struct multiboot_header *) ((char *) header + 4))
{
if (header->magic == MULTIBOOT_HEADER_MAGIC
&& !(header->magic + header->flags + header->checksum))
break;
}
if (header == 0)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, "no multiboot header found");
goto fail;
}
if (header->flags & UNSUPPORTED_FLAGS)
{
grub_error (GRUB_ERR_UNKNOWN_OS,
"unsupported flag: 0x%x", header->flags);
goto fail;
}
grub_relocator_unload (grub_multiboot_relocator);
grub_multiboot_relocator = NULL;
mmap_length = grub_get_multiboot_mmap_len ();
/* Figure out cmdline length. */
/* Skip filename. */
cmdline_argc = argc - 1;
cmdline_argv = argv + 1;
for (i = 0, cmdline_length = 0; i < cmdline_argc; i++)
cmdline_length += grub_strlen (cmdline_argv[i]) + 1;
if (cmdline_length == 0)
cmdline_length = 1;
boot_loader_name_length = sizeof(PACKAGE_STRING);
#define cmdline_addr(x) ((void *) (((grub_uint8_t *) x)))
#define boot_loader_name_addr(x) \
((void *) (((grub_uint8_t *) x) + cmdline_length))
#define mbi_addr(x) ((void *) (((grub_uint8_t *) x) + cmdline_length + boot_loader_name_length))
#define mmap_addr(x) ((void *) (((grub_uint8_t *) x) + cmdline_length + boot_loader_name_length + sizeof (struct multiboot_info)))
mbichunk_size = cmdline_length
/* boot_loader_name_length might need to grow for mbi,etc to be aligned (see below) */
+ boot_loader_name_length + 3
+ sizeof (struct multiboot_info) + mmap_length;
grub_multiboot_relocator = grub_relocator_new ();
if (!grub_multiboot_relocator)
goto fail;
if (header->flags & MULTIBOOT_AOUT_KLUDGE)
{
int offset = ((char *) header - buffer -
(header->header_addr - header->load_addr));
int load_size = ((header->load_end_addr == 0) ? file->size - offset :
header->load_end_addr - header->load_addr);
void *source;
if (header->bss_end_addr)
code_size = (header->bss_end_addr - header->load_addr);
else
code_size = load_size;
err = grub_relocator_alloc_chunk_addr (grub_multiboot_relocator,
&source, header->load_addr,
code_size);
if (err)
{
grub_dprintf ("multiboot_loader", "Error loading aout kludge\n");
goto fail;
}
if ((grub_file_seek (file, offset)) == (grub_off_t) -1)
goto fail;
grub_file_read (file, source, load_size);
if (grub_errno)
goto fail;
if (header->bss_end_addr)
grub_memset ((grub_uint32_t *) source + load_size, 0,
header->bss_end_addr - header->load_addr - load_size);
grub_multiboot_payload_eip = header->entry_addr;
}
else if (grub_multiboot_load_elf (file, buffer) != GRUB_ERR_NONE)
goto fail;
/* This provides alignment for the MBI, the memory map and the backward relocator. */
boot_loader_name_length += (0x04 - ((unsigned long) mbi_addr (0) & 0x03));
err = grub_relocator_alloc_chunk_align (grub_multiboot_relocator, &mbichunk,
&mbichunk_dest,
0, (0xffffffff - mbichunk_size) + 1,
mbichunk_size, 4);
if (err)
{
grub_dprintf ("multiboot_loader", "Error allocating mbi chunk\n");
goto fail;
}
mbi = mbi_addr (mbichunk);
mbi_dest = mbi_addr (mbichunk_dest);
grub_memset (mbi, 0, sizeof (struct multiboot_info));
mbi->mmap_length = mmap_length;
grub_fill_multiboot_mmap (mmap_addr (mbichunk));
mbi->mmap_addr = (grub_uint32_t) mmap_addr (mbichunk_dest);
mbi->flags |= MULTIBOOT_INFO_MEM_MAP;
/* Convert from bytes to kilobytes. */
mbi->mem_lower = grub_mmap_get_lower () / 1024;
mbi->mem_upper = grub_mmap_get_upper () / 1024;
mbi->flags |= MULTIBOOT_INFO_MEMORY;
cmdline = p = cmdline_addr (mbichunk);
if (! cmdline)
goto fail;
for (i = 0; i < cmdline_argc; i++)
{
p = grub_stpcpy (p, cmdline_argv[i]);
*(p++) = ' ';
}
/* Remove the space after the last word. */
if (p != cmdline)
p--;
*p = 0;
mbi->flags |= MULTIBOOT_INFO_CMDLINE;
mbi->cmdline = (grub_uint32_t) cmdline_addr (mbichunk_dest);
grub_strcpy (boot_loader_name_addr (mbichunk), PACKAGE_STRING);
mbi->flags |= MULTIBOOT_INFO_BOOT_LOADER_NAME;
mbi->boot_loader_name = (grub_uint32_t) boot_loader_name_addr (mbichunk_dest);
if (grub_multiboot_get_bootdev (&mbi->boot_device))
mbi->flags |= MULTIBOOT_INFO_BOOTDEV;
grub_loader_set (grub_multiboot_boot, grub_multiboot_unload, 0);
fail:
if (file)
grub_file_close (file);
if (grub_errno != GRUB_ERR_NONE)
{
grub_free (cmdline);
grub_free (mbi);
grub_dl_unref (my_mod);
}
}
void
grub_module (int argc, char *argv[])
{
grub_file_t file = 0;
grub_ssize_t size, len = 0;
char *module = 0, *cmdline = 0, *p;
int i;
int cmdline_argc;
char **cmdline_argv;
if (argc == 0)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, "no module specified");
goto fail;
}
if (!mbi)
{
grub_error (GRUB_ERR_BAD_ARGUMENT,
"you need to load the multiboot kernel first");
goto fail;
}
file = grub_gzfile_open (argv[0], 1);
if (! file)
goto fail;
size = grub_file_size (file);
module = grub_memalign (MULTIBOOT_MOD_ALIGN, size);
if (! module)
goto fail;
if (grub_file_read (file, module, size) != size)
{
grub_error (GRUB_ERR_FILE_READ_ERROR, "couldn't read file");
goto fail;
}
/* Skip module name. */
cmdline_argc = argc - 1;
cmdline_argv = argv + 1;
for (i = 0; i < cmdline_argc; i++)
len += grub_strlen (cmdline_argv[i]) + 1;
if (len == 0)
len = 1;
cmdline = p = grub_malloc (len);
if (! cmdline)
goto fail;
for (i = 0; i < cmdline_argc; i++)
{
p = grub_stpcpy (p, cmdline_argv[i]);
*(p++) = ' ';
}
/* Remove the space after the last word. */
if (p != cmdline)
p--;
*p = '\0';
if (mbi->flags & MULTIBOOT_INFO_MODS)
{
struct multiboot_mod_list *modlist = (struct multiboot_mod_list *) mbi->mods_addr;
modlist = grub_realloc (modlist, (mbi->mods_count + 1)
* sizeof (struct multiboot_mod_list));
if (! modlist)
goto fail;
mbi->mods_addr = (grub_uint32_t) modlist;
modlist += mbi->mods_count;
modlist->mod_start = (grub_uint32_t) module;
modlist->mod_end = (grub_uint32_t) module + size;
modlist->cmdline = (grub_uint32_t) cmdline;
modlist->pad = 0;
mbi->mods_count++;
}
else
{
struct multiboot_mod_list *modlist = grub_zalloc (sizeof (struct multiboot_mod_list));
if (! modlist)
goto fail;
modlist->mod_start = (grub_uint32_t) module;
modlist->mod_end = (grub_uint32_t) module + size;
modlist->cmdline = (grub_uint32_t) cmdline;
mbi->mods_count = 1;
mbi->mods_addr = (grub_uint32_t) modlist;
mbi->flags |= MULTIBOOT_INFO_MODS;
}
fail:
if (file)
grub_file_close (file);
if (grub_errno != GRUB_ERR_NONE)
{
grub_free (module);
grub_free (cmdline);
}
}
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