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/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009-2013 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/mm.h>
#include <grub/misc.h>
#include <grub/types.h>
#include <grub/err.h>
#include <grub/term.h>
#include <grub/relocator.h>
#include <grub/relocator_private.h>
extern grub_uint8_t grub_relocator_forward_start;
extern grub_uint8_t grub_relocator_forward_end;
extern grub_uint8_t grub_relocator_backward_start;
extern grub_uint8_t grub_relocator_backward_end;
extern void *grub_relocator_backward_dest;
extern void *grub_relocator_backward_src;
extern grub_size_t grub_relocator_backward_chunk_size;
extern void *grub_relocator_forward_dest;
extern void *grub_relocator_forward_src;
extern grub_size_t grub_relocator_forward_chunk_size;
#define RELOCATOR_SIZEOF(x) (&grub_relocator##x##_end - &grub_relocator##x##_start)
grub_size_t grub_relocator_align = 1;
grub_size_t grub_relocator_forward_size;
grub_size_t grub_relocator_backward_size;
#ifdef __x86_64__
grub_size_t grub_relocator_jumper_size = 12;
#else
grub_size_t grub_relocator_jumper_size = 7;
#endif
void
grub_cpu_relocator_init (void)
{
grub_relocator_forward_size = RELOCATOR_SIZEOF (_forward);
grub_relocator_backward_size = RELOCATOR_SIZEOF (_backward);
}
void
grub_cpu_relocator_jumper (void *rels, grub_addr_t addr)
{
grub_uint8_t *ptr;
ptr = rels;
#ifdef __x86_64__
/* movq imm64, %rax (for relocator) */
*(grub_uint8_t *) ptr = 0x48;
ptr++;
*(grub_uint8_t *) ptr = 0xb8;
ptr++;
*(grub_uint64_t *) ptr = addr;
ptr += sizeof (grub_uint64_t);
#else
/* movl imm32, %eax (for relocator) */
*(grub_uint8_t *) ptr = 0xb8;
ptr++;
*(grub_uint32_t *) ptr = addr;
ptr += sizeof (grub_uint32_t);
#endif
/* jmp $eax/$rax */
*(grub_uint8_t *) ptr = 0xff;
ptr++;
*(grub_uint8_t *) ptr = 0xe0;
ptr++;
}
void
grub_cpu_relocator_backward (void *ptr, void *src, void *dest,
grub_size_t size)
{
grub_relocator_backward_dest = dest;
grub_relocator_backward_src = src;
grub_relocator_backward_chunk_size = size;
grub_memmove (ptr,
&grub_relocator_backward_start, RELOCATOR_SIZEOF (_backward));
}
void
grub_cpu_relocator_forward (void *ptr, void *src, void *dest,
grub_size_t size)
{
grub_relocator_forward_dest = dest;
grub_relocator_forward_src = src;
grub_relocator_forward_chunk_size = size;
grub_memmove (ptr,
&grub_relocator_forward_start, RELOCATOR_SIZEOF (_forward));
}
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