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i386/relocator: Add grub_relocator64_efi relocator

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Add grub_relocator64_efi relocator. It will be used on EFI 64-bit platforms
when multiboot2 compatible image requests MULTIBOOT_TAG_TYPE_EFI_BS. Relocator
will set lower parts of %rax and %rbx accordingly to multiboot2 specification.
On the other hand processor mode, just before jumping into loaded image, will
be set accordingly to Unified Extensible Firmware Interface Specification,
Version 2.4 Errata B, section 2.3.4, x64 Platforms, boot services. This way
loaded image will be able to use EFI boot services without any issues.

Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
This commit is contained in:
Daniel Kiper 2015-07-17 19:43:42 +02:00
parent e563928ba4
commit 9862b24121
8 changed files with 186 additions and 9 deletions
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11
grub-core/lib/i386/relocator64.S
View file

@ -73,6 +73,14 @@ VARIABLE(grub_relocator64_rsp)
movq %rax, %rsp
/*
* Here is grub_relocator64_efi_start() entry point.
* Following code is shared between grub_relocator64_efi_start()
* and grub_relocator64_start().
*
* Think twice before changing anything below!!!
*/
VARIABLE(grub_relocator64_efi_start)
/* mov imm64, %rax */
.byte 0x48
.byte 0xb8
@ -120,6 +128,9 @@ LOCAL(jump_addr):
VARIABLE(grub_relocator64_rip)
.quad 0
/* Here grub_relocator64_efi_start() ends. Ufff... */
VARIABLE(grub_relocator64_efi_end)
#ifndef __x86_64__
.p2align 4
LOCAL(gdt):

80
grub-core/lib/x86_64/efi/relocator.c Normal file
View file

@ -0,0 +1,80 @@
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 Free Software Foundation, Inc.
* Copyright (C) 2016 Oracle and/or its affiliates. All rights reserved.
*
* 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/i386/relocator.h>
#include <grub/relocator_private.h>
extern grub_uint64_t grub_relocator64_rax;
extern grub_uint64_t grub_relocator64_rbx;
extern grub_uint64_t grub_relocator64_rcx;
extern grub_uint64_t grub_relocator64_rdx;
extern grub_uint64_t grub_relocator64_rip;
extern grub_uint64_t grub_relocator64_rsi;
extern grub_uint8_t grub_relocator64_efi_start;
extern grub_uint8_t grub_relocator64_efi_end;
#define RELOCATOR_SIZEOF(x) (&grub_relocator##x##_end - &grub_relocator##x##_start)
grub_err_t
grub_relocator64_efi_boot (struct grub_relocator *rel,
struct grub_relocator64_efi_state state)
{
grub_err_t err;
void *relst;
grub_relocator_chunk_t ch;
/*
* 64-bit relocator code may live above 4 GiB quite well.
* However, I do not want ask for problems. Just in case.
*/
err = grub_relocator_alloc_chunk_align (rel, &ch, 0,
0x100000000 - RELOCATOR_SIZEOF (64_efi),
RELOCATOR_SIZEOF (64_efi), 16,
GRUB_RELOCATOR_PREFERENCE_NONE, 1);
if (err)
return err;
/* Do not touch %rsp! It points to EFI created stack. */
grub_relocator64_rax = state.rax;
grub_relocator64_rbx = state.rbx;
grub_relocator64_rcx = state.rcx;
grub_relocator64_rdx = state.rdx;
grub_relocator64_rip = state.rip;
grub_relocator64_rsi = state.rsi;
grub_memmove (get_virtual_current_address (ch), &grub_relocator64_efi_start,
RELOCATOR_SIZEOF (64_efi));
err = grub_relocator_prepare_relocs (rel, get_physical_target_address (ch),
&relst, NULL);
if (err)
return err;
((void (*) (void)) relst) ();
/* Not reached. */
return GRUB_ERR_NONE;
}