vbatts
/
grub
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
grub/grub-core/loader/i386/pc/linux.c

456 lines
12 KiB
C
Raw Blame History

/* linux.c - boot Linux zImage or bzImage */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 1999,2000,2001,2002,2003,2004,2005,2007,2008,2009,2010 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/>.
*/
#include <grub/loader.h>
#include <grub/machine/loader.h>
#include <grub/file.h>
#include <grub/err.h>
#include <grub/device.h>
#include <grub/disk.h>
#include <grub/misc.h>
#include <grub/types.h>
#include <grub/machine/memory.h>
#include <grub/dl.h>
#include <grub/cpu/linux.h>
#include <grub/command.h>
#include <grub/i18n.h>
#include <grub/mm.h>
#include <grub/cpu/relocator.h>
#include <grub/video.h>
#include <grub/i386/floppy.h>
#define GRUB_LINUX_CL_OFFSET 0x9000
#define GRUB_LINUX_CL_END_OFFSET 0x90FF
static grub_dl_t my_mod;
static grub_size_t linux_mem_size;
static int loaded;
static struct grub_relocator *relocator = NULL;
static grub_addr_t grub_linux_real_target;
static char *grub_linux_real_chunk;
static grub_size_t grub_linux16_prot_size;
static grub_err_t
grub_linux16_boot (void)
{
grub_uint16_t segment;
struct grub_relocator16_state state;
segment = grub_linux_real_target >> 4;
state.gs = state.fs = state.es = state.ds = state.ss = segment;
state.sp = GRUB_LINUX_SETUP_STACK;
state.cs = segment + 0x20;
state.ip = 0;
grub_video_set_mode ("text", 0, 0);
grub_stop_floppy ();
return grub_relocator16_boot (relocator, state);
}
static grub_err_t
grub_linux_unload (void)
{
grub_dl_unref (my_mod);
loaded = 0;
grub_relocator_unload (relocator);
relocator = NULL;
return GRUB_ERR_NONE;
}
static grub_err_t
grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
int argc, char *argv[])
{
grub_file_t file = 0;
struct linux_kernel_header lh;
grub_uint8_t setup_sects;
grub_size_t real_size;
grub_ssize_t len;
int i;
char *dest;
char *grub_linux_prot_chunk;
int grub_linux_is_bzimage;
grub_addr_t grub_linux_prot_target;
grub_err_t err;
grub_dl_ref (my_mod);
if (argc == 0)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, "no kernel specified");
goto fail;
}
file = grub_file_open (argv[0]);
if (! file)
goto fail;
if (grub_file_read (file, &lh, sizeof (lh)) != sizeof (lh))
{
grub_error (GRUB_ERR_READ_ERROR, "cannot read the Linux header");
goto fail;
}
if (lh.boot_flag != grub_cpu_to_le16 (0xaa55))
{
grub_error (GRUB_ERR_BAD_OS, "invalid magic number");
goto fail;
}
if (lh.setup_sects > GRUB_LINUX_MAX_SETUP_SECTS)
{
grub_error (GRUB_ERR_BAD_OS, "too many setup sectors");
goto fail;
}
grub_linux_is_bzimage = 0;
setup_sects = lh.setup_sects;
linux_mem_size = 0;
if (lh.header == grub_cpu_to_le32 (GRUB_LINUX_MAGIC_SIGNATURE)
&& grub_le_to_cpu16 (lh.version) >= 0x0200)
{
grub_linux_is_bzimage = (lh.loadflags & GRUB_LINUX_FLAG_BIG_KERNEL);
lh.type_of_loader = GRUB_LINUX_BOOT_LOADER_TYPE;
/* Put the real mode part at as a high location as possible. */
grub_linux_real_target = grub_mmap_get_lower ()
- GRUB_LINUX_SETUP_MOVE_SIZE;
/* But it must not exceed the traditional area. */
if (grub_linux_real_target > GRUB_LINUX_OLD_REAL_MODE_ADDR)
grub_linux_real_target = GRUB_LINUX_OLD_REAL_MODE_ADDR;
if (grub_le_to_cpu16 (lh.version) >= 0x0201)
{
lh.heap_end_ptr = grub_cpu_to_le16 (GRUB_LINUX_HEAP_END_OFFSET);
lh.loadflags |= GRUB_LINUX_FLAG_CAN_USE_HEAP;
}
if (grub_le_to_cpu16 (lh.version) >= 0x0202)
lh.cmd_line_ptr = grub_linux_real_target + GRUB_LINUX_CL_OFFSET;
else
{
lh.cl_magic = grub_cpu_to_le16 (GRUB_LINUX_CL_MAGIC);
lh.cl_offset = grub_cpu_to_le16 (GRUB_LINUX_CL_OFFSET);
lh.setup_move_size = grub_cpu_to_le16 (GRUB_LINUX_SETUP_MOVE_SIZE);
}
}
else
{
/* Your kernel is quite old... */
lh.cl_magic = grub_cpu_to_le16 (GRUB_LINUX_CL_MAGIC);
lh.cl_offset = grub_cpu_to_le16 (GRUB_LINUX_CL_OFFSET);
setup_sects = GRUB_LINUX_DEFAULT_SETUP_SECTS;
grub_linux_real_target = GRUB_LINUX_OLD_REAL_MODE_ADDR;
}
/* If SETUP_SECTS is not set, set it to the default (4). */
if (! setup_sects)
setup_sects = GRUB_LINUX_DEFAULT_SETUP_SECTS;
real_size = setup_sects << GRUB_DISK_SECTOR_BITS;
grub_linux16_prot_size = grub_file_size (file)
- real_size - GRUB_DISK_SECTOR_SIZE;
if (! grub_linux_is_bzimage
&& GRUB_LINUX_ZIMAGE_ADDR + grub_linux16_prot_size
> grub_linux_real_target)
{
grub_error (GRUB_ERR_BAD_OS, "too big zImage (0x%x > 0x%x), use bzImage instead",
(char *) GRUB_LINUX_ZIMAGE_ADDR + grub_linux16_prot_size,
(grub_size_t) grub_linux_real_target);
goto fail;
}
if (grub_linux_real_target + GRUB_LINUX_SETUP_MOVE_SIZE
> grub_mmap_get_lower ())
{
grub_error (GRUB_ERR_OUT_OF_RANGE,
"too small lower memory (0x%x > 0x%x)",
grub_linux_real_target + GRUB_LINUX_SETUP_MOVE_SIZE,
(int) grub_mmap_get_lower ());
goto fail;
}
grub_printf (" [Linux-%s, setup=0x%x, size=0x%x]\n",
grub_linux_is_bzimage ? "bzImage" : "zImage", real_size,
grub_linux16_prot_size);
relocator = grub_relocator_new ();
if (!relocator)
goto fail;
for (i = 1; i < argc; i++)
if (grub_memcmp (argv[i], "vga=", 4) == 0)
{
/* Video mode selection support. */
grub_uint16_t vid_mode;
char *val = argv[i] + 4;
if (grub_strcmp (val, "normal") == 0)
vid_mode = GRUB_LINUX_VID_MODE_NORMAL;
else if (grub_strcmp (val, "ext") == 0)
vid_mode = GRUB_LINUX_VID_MODE_EXTENDED;
else if (grub_strcmp (val, "ask") == 0)
vid_mode = GRUB_LINUX_VID_MODE_ASK;
else
vid_mode = (grub_uint16_t) grub_strtoul (val, 0, 0);
if (grub_errno)
goto fail;
lh.vid_mode = grub_cpu_to_le16 (vid_mode);
}
else if (grub_memcmp (argv[i], "mem=", 4) == 0)
{
char *val = argv[i] + 4;
linux_mem_size = grub_strtoul (val, &val, 0);
if (grub_errno)
{
grub_errno = GRUB_ERR_NONE;
linux_mem_size = 0;
}
else
{
int shift = 0;
switch (grub_tolower (val[0]))
{
case 'g':
shift += 10;
case 'm':
shift += 10;
case 'k':
shift += 10;
default:
break;
}
/* Check an overflow. */
if (linux_mem_size > (~0UL >> shift))
linux_mem_size = 0;
else
linux_mem_size <<= shift;
}
}
{
grub_relocator_chunk_t ch;
err = grub_relocator_alloc_chunk_addr (relocator, &ch,
grub_linux_real_target,
GRUB_LINUX_SETUP_MOVE_SIZE);
if (err)
return err;
grub_linux_real_chunk = get_virtual_current_address (ch);
}
/* Put the real mode code at the temporary address. */
grub_memmove (grub_linux_real_chunk, &lh, sizeof (lh));
len = real_size + GRUB_DISK_SECTOR_SIZE - sizeof (lh);
if (grub_file_read (file, grub_linux_real_chunk + sizeof (lh), len) != len)
{
grub_error (GRUB_ERR_FILE_READ_ERROR, "couldn't read file");
goto fail;
}
if (lh.header != grub_cpu_to_le32 (GRUB_LINUX_MAGIC_SIGNATURE)
|| grub_le_to_cpu16 (lh.version) < 0x0200)
/* Clear the heap space. */
grub_memset (grub_linux_real_chunk
+ ((setup_sects + 1) << GRUB_DISK_SECTOR_BITS),
0,
((GRUB_LINUX_MAX_SETUP_SECTS - setup_sects - 1)
<< GRUB_DISK_SECTOR_BITS));
/* Specify the boot file. */
dest = grub_stpcpy (grub_linux_real_chunk + GRUB_LINUX_CL_OFFSET,
"BOOT_IMAGE=");
dest = grub_stpcpy (dest, argv[0]);
/* Copy kernel parameters. */
for (i = 1;
i < argc
&& dest + grub_strlen (argv[i]) + 1 < (grub_linux_real_chunk
+ GRUB_LINUX_CL_END_OFFSET);
i++)
{
*dest++ = ' ';
dest = grub_stpcpy (dest, argv[i]);
}
if (grub_linux_is_bzimage)
grub_linux_prot_target = GRUB_LINUX_BZIMAGE_ADDR;
else
grub_linux_prot_target = GRUB_LINUX_ZIMAGE_ADDR;
{
grub_relocator_chunk_t ch;
err = grub_relocator_alloc_chunk_addr (relocator, &ch,
grub_linux_prot_target,
grub_linux16_prot_size);
if (err)
return err;
grub_linux_prot_chunk = get_virtual_current_address (ch);
}
len = grub_linux16_prot_size;
if (grub_file_read (file, grub_linux_prot_chunk, grub_linux16_prot_size)
!= (grub_ssize_t) grub_linux16_prot_size)
grub_error (GRUB_ERR_FILE_READ_ERROR, "couldn't read file");
if (grub_errno == GRUB_ERR_NONE)
{
grub_loader_set (grub_linux16_boot, grub_linux_unload, 0);
loaded = 1;
}
fail:
if (file)
grub_file_close (file);
if (grub_errno != GRUB_ERR_NONE)
{
grub_dl_unref (my_mod);
loaded = 0;
grub_relocator_unload (relocator);
}
return grub_errno;
}
static grub_err_t
grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)),
int argc, char *argv[])
{
grub_file_t file = 0;
grub_ssize_t size;
grub_addr_t addr_max, addr_min;
struct linux_kernel_header *lh;
grub_uint8_t *initrd_chunk;
grub_addr_t initrd_addr;
grub_err_t err;
if (argc == 0)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, "no module specified");
goto fail;
}
if (!loaded)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, "you need to load the kernel first");
goto fail;
}
lh = (struct linux_kernel_header *) grub_linux_real_chunk;
if (!(lh->header == grub_cpu_to_le32 (GRUB_LINUX_MAGIC_SIGNATURE)
&& grub_le_to_cpu16 (lh->version) >= 0x0200))
{
grub_error (GRUB_ERR_BAD_OS, "the kernel is too old for initrd");
goto fail;
}
/* Get the highest address available for the initrd. */
if (grub_le_to_cpu16 (lh->version) >= 0x0203)
{
addr_max = grub_cpu_to_le32 (lh->initrd_addr_max);
/* XXX in reality, Linux specifies a bogus value, so
it is necessary to make sure that ADDR_MAX does not exceed
0x3fffffff. */
if (addr_max > GRUB_LINUX_INITRD_MAX_ADDRESS)
addr_max = GRUB_LINUX_INITRD_MAX_ADDRESS;
}
else
addr_max = GRUB_LINUX_INITRD_MAX_ADDRESS;
if (linux_mem_size != 0 && linux_mem_size < addr_max)
addr_max = linux_mem_size;
/* Linux 2.3.xx has a bug in the memory range check, so avoid
the last page.
Linux 2.2.xx has a bug in the memory range check, which is
worse than that of Linux 2.3.xx, so avoid the last 64kb. */
addr_max -= 0x10000;
addr_min = GRUB_LINUX_BZIMAGE_ADDR + grub_linux16_prot_size;
grub_file_filter_disable_compression ();
file = grub_file_open (argv[0]);
if (!file)
goto fail;
size = grub_file_size (file);
{
grub_relocator_chunk_t ch;
err = grub_relocator_alloc_chunk_align (relocator, &ch,
addr_min, addr_max - size,
size, 0x1000,
GRUB_RELOCATOR_PREFERENCE_HIGH);
if (err)
return err;
initrd_chunk = get_virtual_current_address (ch);
initrd_addr = get_physical_target_address (ch);
}
if (grub_file_read (file, initrd_chunk, size) != size)
{
grub_error (GRUB_ERR_FILE_READ_ERROR, "couldn't read file");
goto fail;
}
lh->ramdisk_image = initrd_addr;
lh->ramdisk_size = size;
fail:
if (file)
grub_file_close (file);
return grub_errno;
}
static grub_command_t cmd_linux, cmd_initrd;
GRUB_MOD_INIT(linux16)
{
cmd_linux =
grub_register_command ("linux16", grub_cmd_linux,
0, N_("Load Linux."));
cmd_initrd =
grub_register_command ("initrd16", grub_cmd_initrd,
0, N_("Load initrd."));
my_mod = mod;
}
GRUB_MOD_FINI(linux16)
{
grub_unregister_command (cmd_linux);
grub_unregister_command (cmd_initrd);
}
Reference in New Issue View Git Blame Copy Permalink