source: bootcd/isolinux/syslinux-6.03/gpxe/src/image/efi_image.c

/*
 * 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 <gpxe/efi/efi.h>
#include <gpxe/image.h>
#include <gpxe/features.h>

FEATURE ( FEATURE_IMAGE, "EFI", DHCP_EB_FEATURE_EFI, 1 );

struct image_type efi_image_type __image_type ( PROBE_NORMAL );

/**
 * Execute EFI image
 *
 * @v image             EFI image
 * @ret rc              Return status code
 */
static int efi_image_exec ( struct image *image ) {
        EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
        EFI_HANDLE handle;
        UINTN exit_data_size;
        CHAR16 *exit_data;
        EFI_STATUS efirc;

        /* Attempt loading image */
        if ( ( efirc = bs->LoadImage ( FALSE, efi_image_handle, NULL,
                                       user_to_virt ( image->data, 0 ),
                                       image->len, &handle ) ) != 0 ) {
                /* Not an EFI image */
                DBGC ( image, "EFIIMAGE %p could not load: %s\n",
                       image, efi_strerror ( efirc ) );
                return -ENOEXEC;
        }

        /* Start the image */
        if ( ( efirc = bs->StartImage ( handle, &exit_data_size,
                                        &exit_data ) ) != 0 ) {
                DBGC ( image, "EFIIMAGE %p returned with status %s\n",
                       image, efi_strerror ( efirc ) );
                goto done;
        }

 done:
        /* Unload the image.  We can't leave it loaded, because we
         * have no "unload" operation.
         */
        bs->UnloadImage ( handle );

        return EFIRC_TO_RC ( efirc );
}

/**
 * Load EFI image into memory
 *
 * @v image             EFI file
 * @ret rc              Return status code
 */
static int efi_image_load ( struct image *image ) {
        EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
        EFI_HANDLE handle;
        EFI_STATUS efirc;

        /* Attempt loading image */
        if ( ( efirc = bs->LoadImage ( FALSE, efi_image_handle, NULL,
                                       user_to_virt ( image->data, 0 ),
                                       image->len, &handle ) ) != 0 ) {
                /* Not an EFI image */
                DBGC ( image, "EFIIMAGE %p could not load: %s\n",
                       image, efi_strerror ( efirc ) );
                return -ENOEXEC;
        }

        /* This is an EFI image */
        if ( ! image->type )
                image->type = &efi_image_type;

        /* Unload the image.  We can't leave it loaded, because we
         * have no "unload" operation.
         */
        bs->UnloadImage ( handle );

        return 0;
}

/** EFI image type */
struct image_type efi_image_type __image_type ( PROBE_NORMAL ) = {
        .name = "EFI",
        .load = efi_image_load,
        .exec = efi_image_exec,
};