From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Renaud=20M=C3=A9trich?= <rmetrich@redhat.com>

Date: Tue, 15 Feb 2022 14:05:22 +0100

Subject: [PATCH] efi: new 'connectefi' command

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When efi.quickboot is enabled on VMWare (which is the default for

hardware release 16 and later), it may happen that not all EFI devices

are connected. Due to this, browsing the devices in make_devices() just

fails to find devices, in particular disks or partitions for a given

disk.

This typically happens when network booting, then trying to chainload to

local disk (this is used in deployment tools such as Red Hat Satellite),

which is done through using the following grub.cfg snippet:

-------- 8< ---------------- 8< ---------------- 8< --------

unset prefix

search --file --set=prefix /EFI/redhat/grubx64.efi

if [ -n "$prefix" ]; then

  chainloader ($prefix)/EFI/redhat/grubx64/efi

...

-------- 8< ---------------- 8< ---------------- 8< --------

With efi.quickboot, none of the devices are connected, causing "search"

to fail. Sometimes devices are connected but not the partition of the

disk matching $prefix, causing partition to not be found by

"chainloader".

This patch introduces a new "connectefi pciroot|scsi" command which

recursively connects all EFI devices starting from a given controller

type:

- if 'pciroot' is specified, recursion is performed for all PCI root

  handles

- if 'scsi' is specified, recursion is performed for all SCSI I/O

  handles (recommended usage to avoid connecting unwanted handles which

  may impact Grub performances)

Typical grub.cfg snippet would then be:

-------- 8< ---------------- 8< ---------------- 8< --------

connectefi scsi

unset prefix

search --file --set=prefix /EFI/redhat/grubx64.efi

if [ -n "$prefix" ]; then

  chainloader ($prefix)/EFI/redhat/grubx64/efi

...

-------- 8< ---------------- 8< ---------------- 8< --------

The code is easily extensible to handle other arguments in the future if

needed.

Signed-off-by: Renaud M├ętrich <rmetrich@redhat.com>

Signed-off-by: Robbie Harwood <rharwood@redhat.com>

---

 grub-core/Makefile.core.def         |   6 ++

 grub-core/commands/efi/connectefi.c | 205 ++++++++++++++++++++++++++++++++++++

 grub-core/commands/efi/lsefi.c      |   1 +

 grub-core/disk/efi/efidisk.c        |  13 +++

 grub-core/kern/efi/efi.c            |  13 +++

 include/grub/efi/disk.h             |   2 +

 include/grub/efi/efi.h              |   5 +

 NEWS                                |   2 +-

 8 files changed, 246 insertions(+), 1 deletion(-)

 create mode 100644 grub-core/commands/efi/connectefi.c

diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def

index ec1ec5083b..741a033978 100644

--- a/grub-core/Makefile.core.def

+++ b/grub-core/Makefile.core.def

@@ -836,6 +836,12 @@ module = {

   enable = efi;

 };

+module = {

+  name = connectefi;

+  common = commands/efi/connectefi.c;

+  enable = efi;

+};

+

 module = {

   name = blocklist;

   common = commands/blocklist.c;

diff --git a/grub-core/commands/efi/connectefi.c b/grub-core/commands/efi/connectefi.c

new file mode 100644

index 0000000000..8ab75bd51b

--- /dev/null

+++ b/grub-core/commands/efi/connectefi.c

@@ -0,0 +1,205 @@

+/*

+ *  GRUB  --  GRand Unified Bootloader

+ *  Copyright (C) 2022  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/types.h>

+#include <grub/mm.h>

+#include <grub/misc.h>

+#include <grub/efi/api.h>

+#include <grub/efi/pci.h>

+#include <grub/efi/efi.h>

+#include <grub/command.h>

+#include <grub/err.h>

+#include <grub/i18n.h>

+

+GRUB_MOD_LICENSE ("GPLv3+");

+

+typedef struct handle_list

+{

+  grub_efi_handle_t handle;

+  struct handle_list *next;

+} handle_list_t;

+

+static handle_list_t *already_handled = NULL;

+

+static grub_err_t

+add_handle (grub_efi_handle_t handle)

+{

+  handle_list_t *e;

+  e = grub_malloc (sizeof (*e));

+  if (! e)

+    return grub_errno;

+  e->handle = handle;

+  e->next = already_handled;

+  already_handled = e;

+  return GRUB_ERR_NONE;

+}

+

+static int

+is_in_list (grub_efi_handle_t handle)

+{

+  handle_list_t *e;

+  for (e = already_handled; e != NULL; e = e->next)

+    if (e->handle == handle)

+      return 1;

+  return 0;

+}

+

+static void

+free_handle_list (void)

+{

+  handle_list_t *e;

+  while ((e = already_handled) != NULL)

+    {

+      already_handled = already_handled->next;

+      grub_free (e);

+    }

+}

+

+typedef enum searched_item_flag

+{

+  SEARCHED_ITEM_FLAG_LOOP = 1,

+  SEARCHED_ITEM_FLAG_RECURSIVE = 2

+} searched_item_flags;

+

+typedef struct searched_item

+{

+  grub_efi_guid_t guid;

+  const char *name;

+  searched_item_flags flags;

+} searched_items;

+

+static grub_err_t

+grub_cmd_connectefi (grub_command_t cmd __attribute__ ((unused)),

+		     int argc, char **args)

+{

+  unsigned s;

+  searched_items pciroot_items[] =

+    {

+      { GRUB_EFI_PCI_ROOT_IO_GUID, "PCI root", SEARCHED_ITEM_FLAG_RECURSIVE }

+    };

+  searched_items scsi_items[] =

+    {

+      { GRUB_EFI_PCI_ROOT_IO_GUID, "PCI root", 0 },

+      { GRUB_EFI_PCI_IO_GUID, "PCI", SEARCHED_ITEM_FLAG_LOOP },

+      { GRUB_EFI_SCSI_IO_PROTOCOL_GUID, "SCSI I/O", SEARCHED_ITEM_FLAG_RECURSIVE }

+    };

+  searched_items *items = NULL;

+  unsigned nitems = 0;

+  grub_err_t grub_err = GRUB_ERR_NONE;

+  unsigned total_connected = 0;

+

+  if (argc != 1)

+    return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));

+

+  if (grub_strcmp(args[0], N_("pciroot")) == 0)

+    {

+      items = pciroot_items;

+      nitems = ARRAY_SIZE (pciroot_items);

+    }

+  else if (grub_strcmp(args[0], N_("scsi")) == 0)

+    {

+      items = scsi_items;

+      nitems = ARRAY_SIZE (scsi_items);

+    }

+  else

+    return grub_error (GRUB_ERR_BAD_ARGUMENT,

+		       N_("unexpected argument `%s'"), args[0]);

+

+  for (s = 0; s < nitems; s++)

+    {

+      grub_efi_handle_t *handles;

+      grub_efi_uintn_t num_handles;

+      unsigned i, connected = 0, loop = 0;

+

+loop:

+      loop++;

+      grub_dprintf ("efi", "step '%s' loop %d:\n", items[s].name, loop);

+

+      handles = grub_efi_locate_handle (GRUB_EFI_BY_PROTOCOL,

+					&items[s].guid, 0, &num_handles);

+

+      if (!handles)

+	continue;

+

+      for (i = 0; i < num_handles; i++)

+	{

+	  grub_efi_handle_t handle = handles[i];

+	  grub_efi_status_t status;

+	  unsigned j;

+

+	  /* Skip already handled handles  */

+	  if (is_in_list (handle))

+	    {

+	      grub_dprintf ("efi", "  handle %p: already processed\n",

+				   handle);

+	      continue;

+	    }

+

+	  status = grub_efi_connect_controller(handle, NULL, NULL,

+			items[s].flags & SEARCHED_ITEM_FLAG_RECURSIVE ? 1 : 0);

+	  if (status == GRUB_EFI_SUCCESS)

+	    {

+	      connected++;

+	      total_connected++;

+	      grub_dprintf ("efi", "  handle %p: connected\n", handle);

+	    }

+	  else

+	    grub_dprintf ("efi", "  handle %p: failed to connect (%d)\n",

+				 handle, (grub_efi_int8_t) status);

+

+	  if ((grub_err = add_handle (handle)) != GRUB_ERR_NONE)

+	    break; /* fatal  */

+	}

+

+      grub_free (handles);

+      if (grub_err != GRUB_ERR_NONE)

+	break; /* fatal  */

+

+      if (items[s].flags & SEARCHED_ITEM_FLAG_LOOP && connected)

+	{

+	  connected = 0;

+	  goto loop;

+	}

+

+      free_handle_list ();

+    }

+

+  free_handle_list ();

+

+  if (total_connected)

+    grub_efidisk_reenumerate_disks ();

+

+  return grub_err;

+}

+

+static grub_command_t cmd;

+

+GRUB_MOD_INIT(connectefi)

+{

+  cmd = grub_register_command ("connectefi", grub_cmd_connectefi,

+			       N_("pciroot|scsi"),

+			       N_("Connect EFI handles."

+				  " If 'pciroot' is specified, connect PCI"

+				  " root EFI handles recursively."

+				  " If 'scsi' is specified, connect SCSI"

+				  " I/O EFI handles recursively."));

+}

+

+GRUB_MOD_FINI(connectefi)

+{

+  grub_unregister_command (cmd);

+}

diff --git a/grub-core/commands/efi/lsefi.c b/grub-core/commands/efi/lsefi.c

index d1ce99af43..f2d2430e66 100644

--- a/grub-core/commands/efi/lsefi.c

+++ b/grub-core/commands/efi/lsefi.c

@@ -19,6 +19,7 @@

 #include <grub/mm.h>

 #include <grub/misc.h>

 #include <grub/efi/api.h>

+#include <grub/efi/disk.h>

 #include <grub/efi/edid.h>

 #include <grub/efi/pci.h>

 #include <grub/efi/efi.h>

diff --git a/grub-core/disk/efi/efidisk.c b/grub-core/disk/efi/efidisk.c

index fe8ba6e6c9..062143dfff 100644

--- a/grub-core/disk/efi/efidisk.c

+++ b/grub-core/disk/efi/efidisk.c

@@ -396,6 +396,19 @@ enumerate_disks (void)

   free_devices (devices);

 }

+void

+grub_efidisk_reenumerate_disks (void)

+{

+  free_devices (fd_devices);

+  free_devices (hd_devices);

+  free_devices (cd_devices);

+  fd_devices = 0;

+  hd_devices = 0;

+  cd_devices = 0;

+

+  enumerate_disks ();

+}

+

 static int

 grub_efidisk_iterate (grub_disk_dev_iterate_hook_t hook, void *hook_data,

 		      grub_disk_pull_t pull)

diff --git a/grub-core/kern/efi/efi.c b/grub-core/kern/efi/efi.c

index 14bc10eb56..7fcca69c17 100644

--- a/grub-core/kern/efi/efi.c

+++ b/grub-core/kern/efi/efi.c

@@ -95,6 +95,19 @@ grub_efi_locate_handle (grub_efi_locate_search_type_t search_type,

   return buffer;

 }

+grub_efi_status_t

+grub_efi_connect_controller (grub_efi_handle_t controller_handle,

+			     grub_efi_handle_t *driver_image_handle,

+			     grub_efi_device_path_protocol_t *remaining_device_path,

+			     grub_efi_boolean_t recursive)

+{

+  grub_efi_boot_services_t *b;

+

+  b = grub_efi_system_table->boot_services;

+  return efi_call_4 (b->connect_controller, controller_handle,

+		     driver_image_handle, remaining_device_path, recursive);

+}

+

 void *

 grub_efi_open_protocol (grub_efi_handle_t handle,

 			grub_efi_guid_t *protocol,

diff --git a/include/grub/efi/disk.h b/include/grub/efi/disk.h

index 254475c842..6845c2f1fd 100644

--- a/include/grub/efi/disk.h

+++ b/include/grub/efi/disk.h

@@ -27,6 +27,8 @@ grub_efi_handle_t

 EXPORT_FUNC(grub_efidisk_get_device_handle) (grub_disk_t disk);

 char *EXPORT_FUNC(grub_efidisk_get_device_name) (grub_efi_handle_t *handle);

+void EXPORT_FUNC(grub_efidisk_reenumerate_disks) (void);

+

 void grub_efidisk_init (void);

 void grub_efidisk_fini (void);

diff --git a/include/grub/efi/efi.h b/include/grub/efi/efi.h

index 8dfc89a33b..ec52083c49 100644

--- a/include/grub/efi/efi.h

+++ b/include/grub/efi/efi.h

@@ -41,6 +41,11 @@ EXPORT_FUNC(grub_efi_locate_handle) (grub_efi_locate_search_type_t search_type,

 				     grub_efi_guid_t *protocol,

 				     void *search_key,

 				     grub_efi_uintn_t *num_handles);

+grub_efi_status_t

+EXPORT_FUNC(grub_efi_connect_controller) (grub_efi_handle_t controller_handle,

+					  grub_efi_handle_t *driver_image_handle,

+					  grub_efi_device_path_protocol_t *remaining_device_path,

+					  grub_efi_boolean_t recursive);

 void *EXPORT_FUNC(grub_efi_open_protocol) (grub_efi_handle_t handle,

 					   grub_efi_guid_t *protocol,

 					   grub_efi_uint32_t attributes);

diff --git a/NEWS b/NEWS

index 73b8492bc4..d7c1d23aed 100644

--- a/NEWS

+++ b/NEWS

@@ -98,7 +98,7 @@ New in 2.02:

   * Prefer pmtimer for TSC calibration.

 * New/improved platform support:

-  * New `efifwsetup' and `lsefi' commands on EFI platforms.

+  * New `efifwsetup', `lsefi' and `connectefi` commands on EFI platforms.

   * New `cmosdump' and `cmosset' commands on platforms with CMOS support.

   * New command `pcidump' for PCI platforms.

   * Improve opcode parsing in ACPI halt implementation.