grub/lib/relocator.c
Vladimir 'phcoder' Serbinenko 3d1933fb20 Fix compilation on x86_64-efi
2009-11-27 10:57:52 +01:00

137 lines
4.2 KiB
C

/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 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/>.
*/
#define MAX_OVERHEAD ((RELOCATOR_SIZEOF (forward) + RELOCATOR_ALIGN) \
+ (RELOCATOR_SIZEOF (backward) + RELOCATOR_ALIGN) \
+ (RELOCATOR_SIZEOF (forward) + RELOCATOR_ALIGN) \
+ (RELOCATOR_SIZEOF (backward) + RELOCATOR_ALIGN))
#define PRE_REGION_SIZE (RELOCATOR_SIZEOF (backward) + RELOCATOR_ALIGN)
void *
PREFIX (alloc) (grub_size_t size)
{
char *playground;
playground = grub_malloc (size + MAX_OVERHEAD);
if (!playground)
return 0;
*(grub_size_t *) playground = size;
return playground + PRE_REGION_SIZE;
}
void *
PREFIX (realloc) (void *relocator, grub_size_t size)
{
char *playground;
if (!relocator)
return PREFIX (alloc) (size);
playground = (char *) relocator - PRE_REGION_SIZE;
playground = grub_realloc (playground, size + MAX_OVERHEAD);
if (!playground)
return 0;
*(grub_size_t *) playground = size;
return playground + PRE_REGION_SIZE;
}
void
PREFIX(free) (void *relocator)
{
if (relocator)
grub_free ((char *) relocator - PRE_REGION_SIZE);
}
grub_err_t
PREFIX (boot) (void *relocator, grub_uint32_t dest,
struct grub_relocator32_state state)
{
grub_size_t size;
char *playground;
playground = (char *) relocator - PRE_REGION_SIZE;
size = *(grub_size_t *) playground;
grub_dprintf ("relocator",
"Relocator: source: %p, destination: 0x%x, size: 0x%lx\n",
relocator, (unsigned) dest, (unsigned long) size);
/* Very unlikely condition: Relocator may risk overwrite itself.
Just move it a bit up. */
if ((grub_uint8_t *) UINT_TO_PTR (dest) - (grub_uint8_t *) relocator
< (signed) (RELOCATOR_SIZEOF (backward) + RELOCATOR_ALIGN)
&& (grub_uint8_t *) UINT_TO_PTR (dest) - (grub_uint8_t *) relocator
> - (signed) (RELOCATOR_SIZEOF (forward) + RELOCATOR_ALIGN))
{
void *relocator_new = ((grub_uint8_t *) relocator)
+ (RELOCATOR_SIZEOF (forward) + RELOCATOR_ALIGN)
+ (RELOCATOR_SIZEOF (backward) + RELOCATOR_ALIGN);
grub_dprintf ("relocator", "Overwrite condition detected moving "
"relocator from %p to %p\n", relocator, relocator_new);
grub_memmove (relocator_new, relocator,
(RELOCATOR_SIZEOF (forward) + RELOCATOR_ALIGN)
+ size
+ (RELOCATOR_SIZEOF (backward) + RELOCATOR_ALIGN));
relocator = relocator_new;
}
if (UINT_TO_PTR (dest) >= relocator)
{
int overhead;
overhead = dest -
ALIGN_UP (dest - RELOCATOR_SIZEOF (backward) - RELOCATOR_ALIGN,
RELOCATOR_ALIGN);
grub_dprintf ("relocator",
"Backward relocator: code %p, source: %p, "
"destination: 0x%x, size: 0x%lx\n",
(char *) relocator - overhead,
(char *) relocator - overhead,
(unsigned) dest - overhead,
(unsigned long) size + overhead);
write_call_relocator_bw ((char *) relocator - overhead,
(char *) relocator - overhead,
dest - overhead, size + overhead, state);
}
else
{
int overhead;
overhead = ALIGN_UP (dest + size, RELOCATOR_ALIGN)
+ RELOCATOR_SIZEOF (forward) - (dest + size);
grub_dprintf ("relocator",
"Forward relocator: code %p, source: %p, "
"destination: 0x%x, size: 0x%lx\n",
(char *) relocator + size + overhead
- RELOCATOR_SIZEOF (forward),
relocator, (unsigned) dest,
(unsigned long) size + overhead);
write_call_relocator_fw ((char *) relocator + size + overhead
- RELOCATOR_SIZEOF (forward),
relocator, dest, size + overhead, state);
}
/* Not reached. */
return GRUB_ERR_NONE;
}