Re: [Linaro-uefi] [PATCH v3 2/4] arm64: Add xen_boot module file

Committed without the xen_module command. Its argument parsing was non-trivial and I don't quite get what its intent is. Can you resubmit? On 23.07.2015 07:16, fu.wei@linaro.org wrote:

From: Fu Wei fu.wei@linaro.org

grub-core/loader/arm64/xen_boot.c

• This adds support for the Xen boot on ARM specification for arm64.
• Introduce xen_hypervisor, xen_linux, xen_initrd and xen_xsm to load different binaries for xen boot; Introduce xen_module to load common or custom module for xen boot.
• This Xen boot support is a separated module for aarch64, but reuse the existing code of devicetree in linux module.

Signed-off-by: Fu Wei fu.wei@linaro.org

grub-core/Makefile.core.def | 7 + grub-core/loader/arm64/xen_boot.c | 685 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 692 insertions(+)

diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def index a6101de..796f7e9 100644 --- a/grub-core/Makefile.core.def +++ b/grub-core/Makefile.core.def @@ -1648,6 +1648,13 @@ module = { }; module = {

• name = xen_boot;
• common = lib/cmdline.c;
• arm64 = loader/arm64/xen_boot.c;
• enable = arm64;

+};

+module = { name = linux; x86 = loader/i386/linux.c; xen = loader/i386/xen.c; diff --git a/grub-core/loader/arm64/xen_boot.c b/grub-core/loader/arm64/xen_boot.c new file mode 100644 index 0000000..33a65dd --- /dev/null +++ b/grub-core/loader/arm64/xen_boot.c @@ -0,0 +1,685 @@ +/*

• • GRUB -- GRand Unified Bootloader
• • Copyright (C) 2014 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/cache.h> +#include <grub/charset.h> +#include <grub/command.h> +#include <grub/err.h> +#include <grub/file.h> +#include <grub/fdt.h> +#include <grub/linux.h> +#include <grub/list.h> +#include <grub/loader.h> +#include <grub/misc.h> +#include <grub/mm.h> +#include <grub/types.h> +#include <grub/cpu/linux.h> +#include <grub/efi/efi.h> +#include <grub/efi/pe32.h> /* required by struct xen_hypervisor_header */ +#include <grub/i18n.h> +#include <grub/lib/cmdline.h>

+GRUB_MOD_LICENSE ("GPLv3+");

+#define XEN_HYPERVISOR_NAME "xen_hypervisor"

+#define MODULE_DEFAULT_ALIGN (0x0) +#define MODULE_IMAGE_MIN_ALIGN MODULE_DEFAULT_ALIGN +#define MODULE_INITRD_MIN_ALIGN MODULE_DEFAULT_ALIGN +#define MODULE_XSM_MIN_ALIGN MODULE_DEFAULT_ALIGN +#define MODULE_CUSTOM_MIN_ALIGN MODULE_DEFAULT_ALIGN

+/* #define MODULE_IMAGE_COMPATIBLE "xen,linux-image\0xen,module" +#define MODULE_INITRD_COMPATIBLE "xen,linux-image\0xen,module" +#define MODULE_XSM_COMPATIBLE "xen,xsm-policy\0xen,module" +#define MODULE_CUSTOM_COMPATIBLE "xen,module" */ +#define MODULE_IMAGE_COMPATIBLE "multiboot,kernel\0multiboot,module" +#define MODULE_INITRD_COMPATIBLE "multiboot,ramdisk\0multiboot,module" +#define MODULE_XSM_COMPATIBLE "xen,xsm-policy\0multiboot,module" +#define MODULE_CUSTOM_COMPATIBLE "multiboot,module"

+/* This maximum size is defined in Power.org ePAPR V1.1

• • https://www.power.org/documentation/epapr-version-1-1/
• • 2.2.1.1 Node Name Requirements
• • node-name@unit-address
• • 31 + 1(@) + 16(64bit address in hex format) + 1(\0) = 49
• */

+#define FDT_NODE_NAME_MAX_SIZE (49)

+#define ARG_SHIFT(argc, argv) \

• do { \
• (argc)--; \
• (argv)++; \
• } while (0)

+struct compat_string_struct +{

• grub_size_t size;
• const char *compat_string;

+}; +typedef struct compat_string_struct compat_string_struct_t; +#define FDT_COMPATIBLE(x) {.size = sizeof(x), .compat_string = (x)}

+enum module_type +{

• MODULE_IMAGE,
• MODULE_INITRD,
• MODULE_XSM,
• MODULE_CUSTOM

+}; +typedef enum module_type module_type_t;

+struct fdt_node_info +{

• module_type_t type;
• const char *compat_string;
• grub_size_t compat_string_size;

+};

+struct xen_hypervisor_header +{

• struct grub_arm64_linux_kernel_header efi_head;
• /* This is always PE\0\0. */
• grub_uint8_t signature[GRUB_PE32_SIGNATURE_SIZE];
• /* The COFF file header. */
• struct grub_pe32_coff_header coff_header;
• /* The Optional header. */
• struct grub_pe64_optional_header optional_header;

+};

+struct xen_boot_binary +{

• struct xen_boot_binary *next;
• struct xen_boot_binary **prev;
• const char *name;
• grub_addr_t start;
• grub_size_t size;
• grub_size_t align;
• char *cmdline;
• int cmdline_size;
• struct fdt_node_info node_info;

+};

+static grub_dl_t my_mod;

+static struct xen_boot_binary *xen_hypervisor; +static struct xen_boot_binary *module_head; +static const grub_size_t module_default_align[] = {

• MODULE_IMAGE_MIN_ALIGN,
• MODULE_INITRD_MIN_ALIGN,
• MODULE_XSM_MIN_ALIGN,
• MODULE_CUSTOM_MIN_ALIGN

+};

+static void *xen_boot_fdt; +static const compat_string_struct_t default_compat_string[] = {

• FDT_COMPATIBLE (MODULE_IMAGE_COMPATIBLE),
• FDT_COMPATIBLE (MODULE_INITRD_COMPATIBLE),
• FDT_COMPATIBLE (MODULE_XSM_COMPATIBLE),
• FDT_COMPATIBLE (MODULE_CUSTOM_COMPATIBLE)

+};

+static __inline grub_addr_t +xen_boot_address_align (grub_addr_t start, grub_size_t align) +{

• return (align ? (ALIGN_UP (start, align)) : start);

+}

+/* Parse the option of xen_module command. For now, we support

• (1) --type <the compatible stream>
• We also set up the type of module in this function.
• If there are some "--type" options in the command line,
• we make a custom compatible stream in this function. */

+static grub_err_t +set_module_type (grub_command_t cmd, struct xen_boot_binary *module,

•  int argc, char *argv[], int *file_name_index)
  

+{

• char **compat_string_temp_array;
• grub_size_t total_size = 0;
• int num_types = 0, i;
• char *temp = NULL;
• *file_name_index = 0;
• if (!grub_strcmp (cmd->name, "xen_linux"))
• module->node_info.type = MODULE_IMAGE;
• else if (!grub_strcmp (cmd->name, "xen_initrd"))
• module->node_info.type = MODULE_INITRD;
• else if (!grub_strcmp (cmd->name, "xen_xsm"))
• module->node_info.type = MODULE_XSM;
• else if (!grub_strcmp (cmd->name, "xen_module"))
• module->node_info.type = MODULE_CUSTOM;
• /* if there are some options we need to process. */
• if (module->node_info.type == MODULE_CUSTOM)
• {

•  compat_string_temp_array =
  

• (char **) grub_zalloc (sizeof (char *) * argc);

•  if (!compat_string_temp_array)
  

• return grub_errno;

•  /* the module type is set by "--type"(MODULE_CUSTOM) */
  

•  while (argc > 2 && !grub_strcmp (argv[0], "--type"))
  

• {

•  module->node_info.type = MODULE_CUSTOM;
  

•  ARG_SHIFT (argc, argv);
  

•  total_size += grub_strlen (argv[0]) + 1;
  

•  compat_string_temp_array[num_types++] = argv[0];
  

•  ARG_SHIFT (argc, argv);
  

•  (*file_name_index) += 2;
  

• }

•  if (total_size)
  

• {

•  module->node_info.compat_string = temp =
  

•    (char *) grub_zalloc (total_size);
  

•  if (!temp)
  

•    {
  

•      grub_free (compat_string_temp_array);
  

•      return grub_errno;
  

•    }
  

•  module->node_info.compat_string_size = total_size;
  

•  for (i = 0; num_types > 0; num_types--, i++, temp++)
  

•    {
  

•      grub_strcpy (temp, compat_string_temp_array[i]);
  

•      temp += grub_strlen (compat_string_temp_array[i]);
  

•    }
  

• }

•  else
  

• {

•  module->node_info.compat_string =
  

•    default_compat_string[MODULE_CUSTOM].compat_string;
  

•  module->node_info.compat_string_size =
  

•    default_compat_string[MODULE_CUSTOM].size;
  

• }

•  grub_free (compat_string_temp_array);
  

• }
• return GRUB_ERR_NONE;

+}

+static grub_err_t +prepare_xen_hypervisor_params (void) +{

• int chosen_node = 0;
• int retval;
• xen_boot_fdt = grub_linux_get_fdt ();
• if (!xen_boot_fdt)
• return grub_error (GRUB_ERR_IO, "failed to get FDT");
• chosen_node = grub_fdt_find_subnode (xen_boot_fdt, 0, "chosen");
• if (chosen_node < 0)
• chosen_node = grub_fdt_add_subnode (xen_boot_fdt, 0, "chosen");
• if (chosen_node < 1)
• return grub_error (GRUB_ERR_IO, "failed to get chosen node in FDT");
• grub_dprintf ("xen_loader",

• "Xen Hypervisor cmdline : %s @ %p size:%d\n",
  

• xen_hypervisor->cmdline, xen_hypervisor->cmdline,
  

• xen_hypervisor->cmdline_size);
  

• retval = grub_fdt_set_prop (xen_boot_fdt, chosen_node, "bootargs",

• 	      xen_hypervisor->cmdline,
  

• 	      xen_hypervisor->cmdline_size);
  

• if (retval)
• return grub_error (GRUB_ERR_IO, "failed to install/update FDT");
• return GRUB_ERR_NONE;

+}

+static grub_err_t +prepare_xen_module_params (struct xen_boot_binary *module) +{

• int retval, chosen_node = 0, module_node = 0;
• char module_name[FDT_NODE_NAME_MAX_SIZE];
• retval = grub_snprintf (module_name, FDT_NODE_NAME_MAX_SIZE, "module@%lx",

• 	  xen_boot_address_align (module->start,
  

• 				  module->align));
  

• grub_dprintf ("xen_loader", "Module node name %s \n", module_name);
• if (retval < (int) sizeof ("module@"))
• return grub_error (GRUB_ERR_IO, N_("failed to get FDT"));
• chosen_node = grub_fdt_find_subnode (xen_boot_fdt, 0, "chosen");
• if (chosen_node < 0)
• chosen_node = grub_fdt_add_subnode (xen_boot_fdt, 0, "chosen");
• if (chosen_node < 1)
• return grub_error (GRUB_ERR_IO, "failed to get chosen node in FDT");
• module_node =
• grub_fdt_find_subnode (xen_boot_fdt, chosen_node, module_name);
• if (module_node < 0)
• module_node =

•  grub_fdt_add_subnode (xen_boot_fdt, chosen_node, module_name);
  

• retval = grub_fdt_set_prop (xen_boot_fdt, module_node, "compatible",

• 	      module->node_info.compat_string,
  

• 	      (grub_uint32_t) module->
  

• 	      node_info.compat_string_size);
  

• if (retval)
• return grub_error (GRUB_ERR_IO, N_("failed to update FDT"));
• grub_dprintf ("xen_loader", "Module %s compatible = %s size = 0x%lx\n",

• module->name, module->node_info.compat_string,
  

• module->node_info.compat_string_size);
  

• retval = grub_fdt_set_reg64 (xen_boot_fdt, module_node,

• 	       xen_boot_address_align (module->start,
  

• 				       module->align),
  

• 	       module->size);
  

• if (retval)
• return grub_error (GRUB_ERR_IO, N_("failed to update FDT"));
• if (module->cmdline && module->cmdline_size > 0)
• {

•  grub_dprintf ("xen_loader",
  

•     "Module %s cmdline : %s @ %p size:%d\n", module->name,
  

•     module->cmdline, module->cmdline, module->cmdline_size);
  

•  retval = grub_fdt_set_prop (xen_boot_fdt, module_node, "bootargs",
  

• 		  module->cmdline, module->cmdline_size + 1);
  

•  if (retval)
  

• return grub_error (GRUB_ERR_IO, "failed to update FDT");
• }
• else
• {

•  grub_dprintf ("xen_loader", "Module %s has not bootargs!\n",
  

•     module->name);
  

• }
• return GRUB_ERR_NONE;

+}

+static grub_err_t +install_all_params (void) +{

• grub_efi_guid_t fdt_guid = GRUB_EFI_DEVICE_TREE_GUID;
• grub_efi_boot_services_t *b;
• grub_efi_status_t status;
• b = grub_efi_system_table->boot_services;
• status = b->install_configuration_table (&fdt_guid, xen_boot_fdt);
• if (status != GRUB_EFI_SUCCESS)
• return grub_error (GRUB_ERR_IO, "failed to install FDT");
• grub_dprintf ("xen_loader",

• "Installed/updated FDT configuration table @ %p\n",
  

• xen_boot_fdt);
  

• return GRUB_ERR_NONE;

+}

+static grub_err_t +clean_all_params (void) +{

• if (xen_boot_fdt)
• {

•  grub_efi_free_pages ((grub_efi_physical_address_t) xen_boot_fdt,
  

• 	   BYTES_TO_PAGES (grub_fdt_get_totalsize
  

• 			   (xen_boot_fdt)));
  

•  xen_boot_fdt = NULL;
  

• }
• return GRUB_ERR_NONE;

+}

+static grub_err_t +finalize_params_xen_boot (void) +{

• struct xen_boot_binary *module;
• if (xen_hypervisor)
• {

•  if (prepare_xen_hypervisor_params () != GRUB_ERR_NONE)
  

• goto fail;
• }
• else
• {

•  grub_dprintf ("xen_loader", "Failed to get Xen Hypervisor info!\n");
  

•  goto fail;
  

• }
• /* Set module params info */
• FOR_LIST_ELEMENTS (module, module_head)
• {
• if (module->start && module->size > 0)

•  {
  

• grub_dprintf ("xen_loader", "Module %s @ 0x%lx size:0x%lx\n",

•       module->name,
  

•       xen_boot_address_align (module->start, module->align),
  

•       module->size);
  

• if (prepare_xen_module_params (module) != GRUB_ERR_NONE)

•  goto fail;
  

•  }
  

• else

•  {
  

• grub_dprintf ("xen_loader", "Module info error: %s!\n", module->name);
• goto fail;

•  }
  

• }
• if (install_all_params () == GRUB_ERR_NONE)
• return GRUB_ERR_NONE;

+fail:

• clean_all_params ();
• return grub_error (GRUB_ERR_IO, "failed to install/update FDT");

+}

+static grub_err_t +xen_boot (void) +{

• grub_err_t err = finalize_params_xen_boot ();
• if (err)
• return err;
• return grub_arm64_uefi_boot_image (xen_hypervisor->start,

• 		     xen_hypervisor->size,
  

• 		     xen_hypervisor->cmdline);
  

+}

+static void +single_binary_unload (struct xen_boot_binary *binary) +{

• if (!binary)
• return;
• if (binary->start && binary->size > 0)
• {

•  grub_efi_free_pages ((grub_efi_physical_address_t) binary->start,
  

• 	   BYTES_TO_PAGES (binary->size + binary->align));
  

• }
• if (binary->cmdline && binary->cmdline_size > 0)
• {

•  grub_free (binary->cmdline);
  

•  grub_dprintf ("xen_loader",
  

•     "Module %s cmdline memory free @ %p size: %d\n",
  

•     binary->name, binary->cmdline, binary->cmdline_size);
  

• }
• if (binary->node_info.type == MODULE_CUSTOM)
• grub_free ((void *) binary->node_info.compat_string);
• if (grub_strcmp (binary->name, XEN_HYPERVISOR_NAME))
• grub_list_remove (GRUB_AS_LIST (binary));
• grub_dprintf ("xen_loader",

• "Module %s struct memory free @ %p size: 0x%lx\n",
  

• binary->name, binary, sizeof (binary));
  

• grub_free (binary);
• return;

+}

+static void +all_binaries_unload (void) +{

• struct xen_boot_binary *binary;
• FOR_LIST_ELEMENTS (binary, module_head)
• {
• single_binary_unload (binary);
• }
• if (xen_hypervisor)
• single_binary_unload (xen_hypervisor);
• return;

+}

+static grub_err_t +xen_unload (void) +{

• grub_linux_set_loaded (0);
• all_binaries_unload ();
• clean_all_params ();
• grub_dl_unref (my_mod);
• return GRUB_ERR_NONE;

+}

+static void +xen_boot_binary_load (struct xen_boot_binary *binary, grub_file_t file,

•       int argc, char *argv[])
  

+{

• binary->size = grub_file_size (file);
• grub_dprintf ("xen_loader", "Xen_boot %s file size: 0x%lx\n",

• binary->name, binary->size);
  

• binary->start = (grub_addr_t) grub_efi_allocate_pages (0,

• 					 (BYTES_TO_PAGES
  

• 					  (binary->size +
  

• 					   binary->align)));
  

• if (!binary->start)
• {

•  grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
  

•  return;
  

• }
• grub_dprintf ("xen_loader", "Xen_boot %s numpages: 0x%lx\n",

• binary->name, BYTES_TO_PAGES (binary->size + binary->align));
  

• if (grub_file_read (file, (void *) xen_boot_address_align (binary->start,

• 					     binary->align),
  

•       binary->size) != (grub_ssize_t) binary->size)
  

• {

•  single_binary_unload (binary);
  

•  grub_error (GRUB_ERR_BAD_OS, N_("premature end of file %s"), argv[0]);
  

•  return;
  

• }
• if (argc > 1)
• {

•  binary->cmdline_size = grub_loader_cmdline_size (argc - 1, argv + 1);
  

•  binary->cmdline = grub_zalloc (binary->cmdline_size);
  

•  if (!binary->cmdline)
  

• {

•  single_binary_unload (binary);
  

•  grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
  

•  return;
  

• }

•  grub_create_loader_cmdline (argc - 1, argv + 1, binary->cmdline,
  

• 		  binary->cmdline_size);
  

•  grub_dprintf ("xen_loader",
  

•     "Xen_boot %s cmdline @ %p %s, size: %d\n", binary->name,
  

•     binary->cmdline, binary->cmdline, binary->cmdline_size);
  

• }
• else
• {

•  binary->cmdline_size = 0;
  

•  binary->cmdline = NULL;
  

• }
• grub_errno = GRUB_ERR_NONE;
• return;

+}

+static grub_err_t +grub_cmd_xen_module (grub_command_t cmd, int argc, char *argv[]) +{

• struct xen_boot_binary *module = NULL;
• int file_name_index = 0;
• grub_file_t file = 0;
• if (!argc)
• {

•  grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
  

•  goto fail;
  

• }
• if (!grub_linux_get_loaded ())
• {

•  grub_error (GRUB_ERR_BAD_ARGUMENT,
  

•   N_("you need to load the Xen Hypervisor first"));
  

•  goto fail;
  

• }
• module =
• (struct xen_boot_binary *) grub_zalloc (sizeof (struct xen_boot_binary));
• if (!module)
• return grub_errno;
• /* process all the options and get module type */
• if (set_module_type (cmd, module, argc, argv, &file_name_index) !=

•  GRUB_ERR_NONE)
  

• goto fail;
• switch (module->node_info.type)
• {
• case MODULE_IMAGE:
• case MODULE_INITRD:
• case MODULE_XSM:

•  module->node_info.compat_string =
  

• default_compat_string[module->node_info.type].compat_string;

•  module->node_info.compat_string_size =
  

• default_compat_string[module->node_info.type].size;

•  break;
  

• case MODULE_CUSTOM:

•  /* we have set the node_info in set_module_type */
  

•  break;
  

• default:

•  return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("invalid argument"));
  

• }
• module->name = module->node_info.compat_string;
• module->align = module_default_align[module->node_info.type];
• grub_dprintf ("xen_loader", "Init %s module and node info:\n"

• "compatible %s\ncompat_string_size 0x%lx\n",
  

• module->name, module->node_info.compat_string,
  

• module->node_info.compat_string_size);
  

• file = grub_file_open (argv[file_name_index]);
• if (!file)
• goto fail;
• xen_boot_binary_load (module, file, argc - file_name_index,

• 	argv + file_name_index);
  

• if (grub_errno == GRUB_ERR_NONE)
• grub_list_push (GRUB_AS_LIST_P (&module_head), GRUB_AS_LIST (module));

+fail:

• if (file)
• grub_file_close (file);
• if (grub_errno != GRUB_ERR_NONE)
• single_binary_unload (module);
• return grub_errno;

+}

+static grub_err_t +grub_cmd_xen_hypervisor (grub_command_t cmd __attribute__ ((unused)),

• 	 int argc, char *argv[])
  

+{

• struct xen_hypervisor_header sh;
• grub_file_t file = NULL;
• grub_dl_ref (my_mod);
• if (!argc)
• {

•  grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
  

•  goto fail;
  

• }
• file = grub_file_open (argv[0]);
• if (!file)
• goto fail;
• if (grub_file_read (file, &sh, sizeof (sh)) != (long) sizeof (sh))
• goto fail;
• if (grub_arm64_uefi_check_image

•  ((struct grub_arm64_linux_kernel_header *) &sh) != GRUB_ERR_NONE)
  

• goto fail;
• grub_file_seek (file, 0);
• /* if another module has called grub_loader_set,

• we need to make sure that another module is unloaded properly */
  

• grub_loader_unset ();
• xen_hypervisor =
• (struct xen_boot_binary *) grub_zalloc (sizeof (struct xen_boot_binary));
• if (!xen_hypervisor)
• return grub_errno;
• xen_hypervisor->name = XEN_HYPERVISOR_NAME;
• xen_hypervisor->align = (grub_size_t) sh.optional_header.section_alignment;
• xen_boot_binary_load (xen_hypervisor, file, argc, argv);
• if (grub_errno == GRUB_ERR_NONE)
• {

•  grub_loader_set (xen_boot, xen_unload, 0);
  

•  grub_linux_set_loaded (1);
  

• }

+fail:

• if (file)
• grub_file_close (file);
• if (grub_errno != GRUB_ERR_NONE)
• {

•  grub_linux_set_loaded (0);
  

•  all_binaries_unload ();
  

•  grub_dl_unref (my_mod);
  

• }
• return grub_errno;

+}

+static grub_command_t cmd_xen_hypervisor, cmd_xen_module; +static grub_command_t cmd_xen_linux, cmd_xen_initrd, cmd_xen_xsm;

+GRUB_MOD_INIT (xen_boot) +{

• cmd_xen_hypervisor =
• grub_register_command ("xen_hypervisor", grub_cmd_xen_hypervisor, 0,

• 	   N_("Load a xen hypervisor."));
  

• cmd_xen_linux =
• grub_register_command ("xen_linux", grub_cmd_xen_module, 0,

• 	   N_("Load a xen linux kernel for dom0."));
  

• cmd_xen_initrd =
• grub_register_command ("xen_initrd", grub_cmd_xen_module, 0,

• 	   N_("Load a xen initrd for dom0."));
  

• cmd_xen_xsm =
• grub_register_command ("xen_xsm", grub_cmd_xen_module, 0,

• 	   N_("Load a xen security module."));
  

• cmd_xen_module =
• grub_register_command ("xen_module", grub_cmd_xen_module, 0,

• 	   N_("Load a xen module."));
  

• my_mod = mod;

+}

+GRUB_MOD_FINI (xen_boot) +{

• grub_unregister_command (cmd_xen_hypervisor);
• grub_unregister_command (cmd_xen_linux);
• grub_unregister_command (cmd_xen_initrd);
• grub_unregister_command (cmd_xen_xsm);
• grub_unregister_command (cmd_xen_module);

+}