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/*
* Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program 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 2 of the
* License, or any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <errno.h>
#include <elf.h>
#include <gpxe/image.h>
#include <gpxe/elf.h>
#include <gpxe/features.h>
#include <gpxe/init.h>
/**
* @file
*
* ELF bootable image
*
*/
FEATURE ( FEATURE_IMAGE, "ELF", DHCP_EB_FEATURE_ELF, 1 );
struct image_type elfboot_image_type __image_type ( PROBE_NORMAL );
/**
* Execute ELF image
*
* @v image ELF image
* @ret rc Return status code
*/
static int elfboot_exec ( struct image *image ) {
physaddr_t entry = image->priv.phys;
/* An ELF image has no callback interface, so we need to shut
* down before invoking it.
*/
shutdown ( SHUTDOWN_BOOT );
/* Jump to OS with flat physical addressing */
DBGC ( image, "ELF %p starting execution at %lx\n", image, entry );
__asm__ __volatile__ ( PHYS_CODE ( "call *%%edi\n\t" )
: : "D" ( entry )
: "eax", "ebx", "ecx", "edx", "esi", "ebp",
"memory" );
DBGC ( image, "ELF %p returned\n", image );
/* It isn't safe to continue after calling shutdown() */
while ( 1 ) {}
return -ECANCELED; /* -EIMPOSSIBLE, anyone? */
}
/**
* Load ELF image into memory
*
* @v image ELF file
* @ret rc Return status code
*/
static int elfboot_load ( struct image *image ) {
Elf32_Ehdr ehdr;
static const uint8_t e_ident[] = {
[EI_MAG0] = ELFMAG0,
[EI_MAG1] = ELFMAG1,
[EI_MAG2] = ELFMAG2,
[EI_MAG3] = ELFMAG3,
[EI_CLASS] = ELFCLASS32,
[EI_DATA] = ELFDATA2LSB,
[EI_VERSION] = EV_CURRENT,
};
int rc;
/* Read ELF header */
copy_from_user ( &ehdr, image->data, 0, sizeof ( ehdr ) );
if ( memcmp ( ehdr.e_ident, e_ident, sizeof ( e_ident ) ) != 0 ) {
DBG ( "Invalid ELF identifier\n" );
return -ENOEXEC;
}
/* This is an ELF image, valid or otherwise */
if ( ! image->type )
image->type = &elfboot_image_type;
/* Load the image using core ELF support */
if ( ( rc = elf_load ( image ) ) != 0 ) {
DBGC ( image, "ELF %p could not load: %s\n",
image, strerror ( rc ) );
return rc;
}
return 0;
}
/** ELF image type */
struct image_type elfboot_image_type __image_type ( PROBE_NORMAL ) = {
.name = "ELF",
.load = elfboot_load,
.exec = elfboot_exec,
};
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