Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86/efi changes from Peter Anvin:
 "The bulk of these changes are cleaning up the efivars handling and
  breaking it up into a tree of files.  There are a number of fixes as
  well.

  The entire changeset is pretty big, but most of it is code movement.

  Several of these commits are quite new; the history got very messed up
  due to a mismerge with the urgent changes for rc8 which completely
  broke IA64, and so Ingo requested that we rebase it to straighten it
  out."

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: remove "kfree(NULL)"
  efi: locking fix in efivar_entry_set_safe()
  efi, pstore: Read data from variable store before memcpy()
  efi, pstore: Remove entry from list when erasing
  efi, pstore: Initialise 'entry' before iterating
  efi: split efisubsystem from efivars
  efivarfs: Move to fs/efivarfs
  efivars: Move pstore code into the new EFI directory
  efivars: efivar_entry API
  efivars: Keep a private global pointer to efivars
  efi: move utf16 string functions to efi.h
  x86, efi: Make efi_memblock_x86_reserve_range more readable
  efivarfs: convert to use simple_open()

MAINTAINERS

@@ -3025,9 +3025,18 @@ F:	arch/ia64/kernel/efi.c
 F:	arch/x86/boot/compressed/eboot.[ch]
 F:	arch/x86/include/asm/efi.h
 F:	arch/x86/platform/efi/*
-F:	drivers/firmware/efivars.c
+F:	drivers/firmware/efi/*
 F:	include/linux/efi*.h
 
+EFI VARIABLE FILESYSTEM
+M:	Matthew Garrett <matthew.garrett@nebula.com>
+M:	Jeremy Kerr <jk@ozlabs.org>
+M:	Matt Fleming <matt.fleming@intel.com>
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git
+L:	linux-efi@vger.kernel.org
+S:	Maintained
+F:	fs/efivarfs/
+
 EFIFB FRAMEBUFFER DRIVER
 L:	linux-fbdev@vger.kernel.org
 M:	Peter Jones <pjones@redhat.com>
@@ -6391,7 +6400,7 @@ S:	Maintained
 T:	git git://git.infradead.org/users/cbou/linux-pstore.git
 F:	fs/pstore/
 F:	include/linux/pstore*
-F:	drivers/firmware/efivars.c
+F:	drivers/firmware/efi/efi-pstore.c
 F:	drivers/acpi/apei/erst.c
 
 PTP HARDWARE CLOCK SUPPORT

arch/ia64/Kconfig

@@ -110,6 +110,7 @@ config DMI
 
 config EFI
 	bool
+	select UCS2_STRING
 	default y
 
 config SCHED_OMIT_FRAME_POINTER

arch/x86/platform/efi/efi.c

@@ -453,24 +453,25 @@ static void __init do_add_efi_memmap(void)
 
 int __init efi_memblock_x86_reserve_range(void)
 {
+	struct efi_info *e = &boot_params.efi_info;
 	unsigned long pmap;
 
 #ifdef CONFIG_X86_32
 	/* Can't handle data above 4GB at this time */
-	if (boot_params.efi_info.efi_memmap_hi) {
+	if (e->efi_memmap_hi) {
 		pr_err("Memory map is above 4GB, disabling EFI.\n");
 		return -EINVAL;
 	}
-	pmap = boot_params.efi_info.efi_memmap;
+	pmap =  e->efi_memmap;
 #else
-	pmap = (boot_params.efi_info.efi_memmap |
-		((__u64)boot_params.efi_info.efi_memmap_hi<<32));
+	pmap = (e->efi_memmap |	((__u64)e->efi_memmap_hi << 32));
 #endif
-	memmap.phys_map = (void *)pmap;
-	memmap.nr_map = boot_params.efi_info.efi_memmap_size /
-		boot_params.efi_info.efi_memdesc_size;
-	memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
-	memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
+	memmap.phys_map		= (void *)pmap;
+	memmap.nr_map		= e->efi_memmap_size /
+				  e->efi_memdesc_size;
+	memmap.desc_size	= e->efi_memdesc_size;
+	memmap.desc_version	= e->efi_memdesc_version;
+
 	memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 
 	return 0;

drivers/firmware/Kconfig

@@ -36,42 +36,6 @@ config FIRMWARE_MEMMAP
 
       See also Documentation/ABI/testing/sysfs-firmware-memmap.
 
-config EFI_VARS
-	tristate "EFI Variable Support via sysfs"
-	depends on EFI
-	select UCS2_STRING
-	default n
-	help
-	  If you say Y here, you are able to get EFI (Extensible Firmware
-	  Interface) variable information via sysfs.  You may read,
-	  write, create, and destroy EFI variables through this interface.
-
-	  Note that using this driver in concert with efibootmgr requires
-	  at least test release version 0.5.0-test3 or later, which is
-	  available from Matt Domsch's website located at:
-	  <http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz>
-
-	  Subsequent efibootmgr releases may be found at:
-	  <http://linux.dell.com/efibootmgr>
-
-config EFI_VARS_PSTORE
-	bool "Register efivars backend for pstore"
-	depends on EFI_VARS && PSTORE
-	default y
-	help
-	  Say Y here to enable use efivars as a backend to pstore. This
-	  will allow writing console messages, crash dumps, or anything
-	  else supported by pstore to EFI variables.
-
-config EFI_VARS_PSTORE_DEFAULT_DISABLE
-	bool "Disable using efivars as a pstore backend by default"
-	depends on EFI_VARS_PSTORE
-	default n
-	help
-	  Saying Y here will disable the use of efivars as a storage
-	  backend for pstore by default. This setting can be overridden
-	  using the efivars module's pstore_disable parameter.
-
 config EFI_PCDP
 	bool "Console device selection via EFI PCDP or HCDP table"
 	depends on ACPI && EFI && IA64
@@ -165,5 +129,6 @@ config ISCSI_IBFT
 	  Otherwise, say N.
 
 source "drivers/firmware/google/Kconfig"
+source "drivers/firmware/efi/Kconfig"
 
 endmenu

drivers/firmware/Makefile

@@ -4,7 +4,6 @@
 obj-$(CONFIG_DMI)		+= dmi_scan.o
 obj-$(CONFIG_DMI_SYSFS)		+= dmi-sysfs.o
 obj-$(CONFIG_EDD)		+= edd.o
-obj-$(CONFIG_EFI_VARS)		+= efivars.o
 obj-$(CONFIG_EFI_PCDP)		+= pcdp.o
 obj-$(CONFIG_DELL_RBU)          += dell_rbu.o
 obj-$(CONFIG_DCDBAS)		+= dcdbas.o
@@ -14,3 +13,4 @@ obj-$(CONFIG_ISCSI_IBFT)	+= iscsi_ibft.o
 obj-$(CONFIG_FIRMWARE_MEMMAP)	+= memmap.o
 
 obj-$(CONFIG_GOOGLE_FIRMWARE)	+= google/
+obj-$(CONFIG_EFI)		+= efi/

drivers/firmware/efi/Kconfig

@@ -0,0 +1,39 @@
+menu "EFI (Extensible Firmware Interface) Support"
+	depends on EFI
+
+config EFI_VARS
+	tristate "EFI Variable Support via sysfs"
+	depends on EFI
+	default n
+	help
+	  If you say Y here, you are able to get EFI (Extensible Firmware
+	  Interface) variable information via sysfs.  You may read,
+	  write, create, and destroy EFI variables through this interface.
+
+	  Note that using this driver in concert with efibootmgr requires
+	  at least test release version 0.5.0-test3 or later, which is
+	  available from Matt Domsch's website located at:
+	  <http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz>
+
+	  Subsequent efibootmgr releases may be found at:
+	  <http://linux.dell.com/efibootmgr>
+
+config EFI_VARS_PSTORE
+	tristate "Register efivars backend for pstore"
+	depends on EFI_VARS && PSTORE
+	default y
+	help
+	  Say Y here to enable use efivars as a backend to pstore. This
+	  will allow writing console messages, crash dumps, or anything
+	  else supported by pstore to EFI variables.
+
+config EFI_VARS_PSTORE_DEFAULT_DISABLE
+	bool "Disable using efivars as a pstore backend by default"
+	depends on EFI_VARS_PSTORE
+	default n
+	help
+	  Saying Y here will disable the use of efivars as a storage
+	  backend for pstore by default. This setting can be overridden
+	  using the efivars module's pstore_disable parameter.
+
+endmenu

drivers/firmware/efi/Makefile

@@ -0,0 +1,6 @@
+#
+# Makefile for linux kernel
+#
+obj-y					+= efi.o vars.o
+obj-$(CONFIG_EFI_VARS)			+= efivars.o
+obj-$(CONFIG_EFI_VARS_PSTORE)		+= efi-pstore.o

drivers/firmware/efi/efi-pstore.c

@@ -0,0 +1,251 @@
+#include <linux/efi.h>
+#include <linux/module.h>
+#include <linux/pstore.h>
+#include <linux/ucs2_string.h>
+
+#define DUMP_NAME_LEN 52
+
+static bool efivars_pstore_disable =
+	IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE);
+
+module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644);
+
+#define PSTORE_EFI_ATTRIBUTES \
+	(EFI_VARIABLE_NON_VOLATILE | \
+	 EFI_VARIABLE_BOOTSERVICE_ACCESS | \
+	 EFI_VARIABLE_RUNTIME_ACCESS)
+
+static int efi_pstore_open(struct pstore_info *psi)
+{
+	efivar_entry_iter_begin();
+	psi->data = NULL;
+	return 0;
+}
+
+static int efi_pstore_close(struct pstore_info *psi)
+{
+	efivar_entry_iter_end();
+	psi->data = NULL;
+	return 0;
+}
+
+struct pstore_read_data {
+	u64 *id;
+	enum pstore_type_id *type;
+	int *count;
+	struct timespec *timespec;
+	char **buf;
+};
+
+static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
+{
+	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+	struct pstore_read_data *cb_data = data;
+	char name[DUMP_NAME_LEN];
+	int i;
+	int cnt;
+	unsigned int part;
+	unsigned long time, size;
+
+	if (efi_guidcmp(entry->var.VendorGuid, vendor))
+		return 0;
+
+	for (i = 0; i < DUMP_NAME_LEN; i++)
+		name[i] = entry->var.VariableName[i];
+
+	if (sscanf(name, "dump-type%u-%u-%d-%lu",
+		   cb_data->type, &part, &cnt, &time) == 4) {
+		*cb_data->id = part;
+		*cb_data->count = cnt;
+		cb_data->timespec->tv_sec = time;
+		cb_data->timespec->tv_nsec = 0;
+	} else if (sscanf(name, "dump-type%u-%u-%lu",
+			  cb_data->type, &part, &time) == 3) {
+		/*
+		 * Check if an old format,
+		 * which doesn't support holding
+		 * multiple logs, remains.
+		 */
+		*cb_data->id = part;
+		*cb_data->count = 0;
+		cb_data->timespec->tv_sec = time;
+		cb_data->timespec->tv_nsec = 0;
+	} else
+		return 0;
+
+	entry->var.DataSize = 1024;
+	__efivar_entry_get(entry, &entry->var.Attributes,
+			   &entry->var.DataSize, entry->var.Data);
+	size = entry->var.DataSize;
+
+	*cb_data->buf = kmalloc(size, GFP_KERNEL);
+	if (*cb_data->buf == NULL)
+		return -ENOMEM;
+	memcpy(*cb_data->buf, entry->var.Data, size);
+	return size;
+}
+
+static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
+			       int *count, struct timespec *timespec,
+			       char **buf, struct pstore_info *psi)
+{
+	struct pstore_read_data data;
+
+	data.id = id;
+	data.type = type;
+	data.count = count;
+	data.timespec = timespec;
+	data.buf = buf;
+
+	return __efivar_entry_iter(efi_pstore_read_func, &efivar_sysfs_list, &data,
+				   (struct efivar_entry **)&psi->data);
+}
+
+static int efi_pstore_write(enum pstore_type_id type,
+		enum kmsg_dump_reason reason, u64 *id,
+		unsigned int part, int count, size_t size,
+		struct pstore_info *psi)
+{
+	char name[DUMP_NAME_LEN];
+	efi_char16_t efi_name[DUMP_NAME_LEN];
+	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+	int i, ret = 0;
+
+	sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count,
+		get_seconds());
+
+	for (i = 0; i < DUMP_NAME_LEN; i++)
+		efi_name[i] = name[i];
+
+	efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES,
+			      !pstore_cannot_block_path(reason),
+			      size, psi->buf);
+
+	if (reason == KMSG_DUMP_OOPS)
+		efivar_run_worker();
+
+	*id = part;
+	return ret;
+};
+
+struct pstore_erase_data {
+	u64 id;
+	enum pstore_type_id type;
+	int count;
+	struct timespec time;
+	efi_char16_t *name;
+};
+
+/*
+ * Clean up an entry with the same name
+ */
+static int efi_pstore_erase_func(struct efivar_entry *entry, void *data)
+{
+	struct pstore_erase_data *ed = data;
+	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+	efi_char16_t efi_name_old[DUMP_NAME_LEN];
+	efi_char16_t *efi_name = ed->name;
+	unsigned long ucs2_len = ucs2_strlen(ed->name);
+	char name_old[DUMP_NAME_LEN];
+	int i;
+
+	if (efi_guidcmp(entry->var.VendorGuid, vendor))
+		return 0;
+
+	if (ucs2_strncmp(entry->var.VariableName,
+			  efi_name, (size_t)ucs2_len)) {
+		/*
+		 * Check if an old format, which doesn't support
+		 * holding multiple logs, remains.
+		 */
+		sprintf(name_old, "dump-type%u-%u-%lu", ed->type,
+			(unsigned int)ed->id, ed->time.tv_sec);
+
+		for (i = 0; i < DUMP_NAME_LEN; i++)
+			efi_name_old[i] = name_old[i];
+
+		if (ucs2_strncmp(entry->var.VariableName, efi_name_old,
+				  ucs2_strlen(efi_name_old)))
+			return 0;
+	}
+
+	/* found */
+	__efivar_entry_delete(entry);
+	list_del(&entry->list);
+
+	return 1;
+}
+
+static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
+			    struct timespec time, struct pstore_info *psi)
+{
+	struct pstore_erase_data edata;
+	struct efivar_entry *entry = NULL;
+	char name[DUMP_NAME_LEN];
+	efi_char16_t efi_name[DUMP_NAME_LEN];
+	int found, i;
+
+	sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count,
+		time.tv_sec);
+
+	for (i = 0; i < DUMP_NAME_LEN; i++)
+		efi_name[i] = name[i];
+
+	edata.id = id;
+	edata.type = type;
+	edata.count = count;
+	edata.time = time;
+	edata.name = efi_name;
+
+	efivar_entry_iter_begin();
+	found = __efivar_entry_iter(efi_pstore_erase_func, &efivar_sysfs_list, &edata, &entry);
+	efivar_entry_iter_end();
+
+	if (found)
+		efivar_unregister(entry);
+
+	return 0;
+}
+
+static struct pstore_info efi_pstore_info = {
+	.owner		= THIS_MODULE,
+	.name		= "efi",
+	.open		= efi_pstore_open,
+	.close		= efi_pstore_close,
+	.read		= efi_pstore_read,
+	.write		= efi_pstore_write,
+	.erase		= efi_pstore_erase,
+};
+
+static __init int efivars_pstore_init(void)
+{
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		return 0;
+
+	if (!efivars_kobject())
+		return 0;
+
+	if (efivars_pstore_disable)
+		return 0;
+
+	efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL);
+	if (!efi_pstore_info.buf)
+		return -ENOMEM;
+
+	efi_pstore_info.bufsize = 1024;
+	spin_lock_init(&efi_pstore_info.buf_lock);
+
+	pstore_register(&efi_pstore_info);
+
+	return 0;
+}
+
+static __exit void efivars_pstore_exit(void)
+{
+}
+
+module_init(efivars_pstore_init);
+module_exit(efivars_pstore_exit);
+
+MODULE_DESCRIPTION("EFI variable backend for pstore");
+MODULE_LICENSE("GPL");

drivers/firmware/efi/efi.c

@@ -0,0 +1,134 @@
+/*
+ * efi.c - EFI subsystem
+ *
+ * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
+ * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
+ * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
+ *
+ * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
+ * allowing the efivarfs to be mounted or the efivars module to be loaded.
+ * The existance of /sys/firmware/efi may also be used by userspace to
+ * determine that the system supports EFI.
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/efi.h>
+
+static struct kobject *efi_kobj;
+static struct kobject *efivars_kobj;
+
+/*
+ * Let's not leave out systab information that snuck into
+ * the efivars driver
+ */
+static ssize_t systab_show(struct kobject *kobj,
+			   struct kobj_attribute *attr, char *buf)
+{
+	char *str = buf;
+
+	if (!kobj || !buf)
+		return -EINVAL;
+
+	if (efi.mps != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "MPS=0x%lx\n", efi.mps);
+	if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
+	if (efi.acpi != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
+	if (efi.smbios != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
+	if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
+	if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
+	if (efi.uga != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "UGA=0x%lx\n", efi.uga);
+
+	return str - buf;
+}
+
+static struct kobj_attribute efi_attr_systab =
+			__ATTR(systab, 0400, systab_show, NULL);
+
+static struct attribute *efi_subsys_attrs[] = {
+	&efi_attr_systab.attr,
+	NULL,	/* maybe more in the future? */
+};
+
+static struct attribute_group efi_subsys_attr_group = {
+	.attrs = efi_subsys_attrs,
+};
+
+static struct efivars generic_efivars;
+static struct efivar_operations generic_ops;
+
+static int generic_ops_register(void)
+{
+	generic_ops.get_variable = efi.get_variable;
+	generic_ops.set_variable = efi.set_variable;
+	generic_ops.get_next_variable = efi.get_next_variable;
+	generic_ops.query_variable_store = efi_query_variable_store;
+
+	return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
+}
+
+static void generic_ops_unregister(void)
+{
+	efivars_unregister(&generic_efivars);
+}
+
+/*
+ * We register the efi subsystem with the firmware subsystem and the
+ * efivars subsystem with the efi subsystem, if the system was booted with
+ * EFI.
+ */
+static int __init efisubsys_init(void)
+{
+	int error;
+
+	if (!efi_enabled(EFI_BOOT))
+		return 0;
+
+	/* We register the efi directory at /sys/firmware/efi */
+	efi_kobj = kobject_create_and_add("efi", firmware_kobj);
+	if (!efi_kobj) {
+		pr_err("efi: Firmware registration failed.\n");
+		return -ENOMEM;
+	}
+
+	error = generic_ops_register();
+	if (error)
+		goto err_put;
+
+	error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
+	if (error) {
+		pr_err("efi: Sysfs attribute export failed with error %d.\n",
+		       error);
+		goto err_unregister;
+	}
+
+	/* and the standard mountpoint for efivarfs */
+	efivars_kobj = kobject_create_and_add("efivars", efi_kobj);
+	if (!efivars_kobj) {
+		pr_err("efivars: Subsystem registration failed.\n");
+		error = -ENOMEM;
+		goto err_remove_group;
+	}
+
+	return 0;
+
+err_remove_group:
+	sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
+err_unregister:
+	generic_ops_unregister();
+err_put:
+	kobject_put(efi_kobj);
+	return error;
+}
+
+subsys_initcall(efisubsys_init);

drivers/firmware/efi/efivars.c

@@ -0,0 +1,616 @@
+/*
+ * Originally from efivars.c,
+ *
+ * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
+ * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
+ *
+ * This code takes all variables accessible from EFI runtime and
+ *  exports them via sysfs
+ *
+ *  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
+ *  (at your option) 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Changelog:
+ *
+ *  17 May 2004 - Matt Domsch <Matt_Domsch@dell.com>
+ *   remove check for efi_enabled in exit
+ *   add MODULE_VERSION
+ *
+ *  26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com>
+ *   minor bug fixes
+ *
+ *  21 Apr 2004 - Matt Tolentino <matthew.e.tolentino@intel.com)
+ *   converted driver to export variable information via sysfs
+ *   and moved to drivers/firmware directory
+ *   bumped revision number to v0.07 to reflect conversion & move
+ *
+ *  10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com>
+ *   fix locking per Peter Chubb's findings
+ *
+ *  25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com>
+ *   move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_unparse()
+ *
+ *  12 Feb 2002 - Matt Domsch <Matt_Domsch@dell.com>
+ *   use list_for_each_safe when deleting vars.
+ *   remove ifdef CONFIG_SMP around include <linux/smp.h>
+ *   v0.04 release to linux-ia64@linuxia64.org
+ *
+ *  20 April 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   Moved vars from /proc/efi to /proc/efi/vars, and made
+ *   efi.c own the /proc/efi directory.
+ *   v0.03 release to linux-ia64@linuxia64.org
+ *
+ *  26 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   At the request of Stephane, moved ownership of /proc/efi
+ *   to efi.c, and now efivars lives under /proc/efi/vars.
+ *
+ *  12 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   Feedback received from Stephane Eranian incorporated.
+ *   efivar_write() checks copy_from_user() return value.
+ *   efivar_read/write() returns proper errno.
+ *   v0.02 release to linux-ia64@linuxia64.org
+ *
+ *  26 February 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   v0.01 release to linux-ia64@linuxia64.org
+ */
+
+#include <linux/efi.h>
+#include <linux/module.h>
+#include <linux/ucs2_string.h>
+
+#define EFIVARS_VERSION "0.08"
+#define EFIVARS_DATE "2004-May-17"
+
+MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
+MODULE_DESCRIPTION("sysfs interface to EFI Variables");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(EFIVARS_VERSION);
+
+LIST_HEAD(efivar_sysfs_list);
+EXPORT_SYMBOL_GPL(efivar_sysfs_list);
+
+static struct kset *efivars_kset;
+
+static struct bin_attribute *efivars_new_var;
+static struct bin_attribute *efivars_del_var;
+
+struct efivar_attribute {
+	struct attribute attr;
+	ssize_t (*show) (struct efivar_entry *entry, char *buf);
+	ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count);
+};
+
+#define EFIVAR_ATTR(_name, _mode, _show, _store) \
+struct efivar_attribute efivar_attr_##_name = { \
+	.attr = {.name = __stringify(_name), .mode = _mode}, \
+	.show = _show, \
+	.store = _store, \
+};
+
+#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr)
+#define to_efivar_entry(obj)  container_of(obj, struct efivar_entry, kobj)
+
+/*
+ * Prototype for sysfs creation function
+ */
+static int
+efivar_create_sysfs_entry(struct efivar_entry *new_var);
+
+static ssize_t
+efivar_guid_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+	char *str = buf;
+
+	if (!entry || !buf)
+		return 0;
+
+	efi_guid_unparse(&var->VendorGuid, str);
+	str += strlen(str);
+	str += sprintf(str, "\n");
+
+	return str - buf;
+}
+
+static ssize_t
+efivar_attr_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+	char *str = buf;
+
+	if (!entry || !buf)
+		return -EINVAL;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
+		return -EIO;
+
+	if (var->Attributes & EFI_VARIABLE_NON_VOLATILE)
+		str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n");
+	if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS)
+		str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n");
+	if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS)
+		str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n");
+	if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
+		str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n");
+	if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS)
+		str += sprintf(str,
+			"EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n");
+	if (var->Attributes &
+			EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
+		str += sprintf(str,
+			"EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n");
+	if (var->Attributes & EFI_VARIABLE_APPEND_WRITE)
+		str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n");
+	return str - buf;
+}
+
+static ssize_t
+efivar_size_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+	char *str = buf;
+
+	if (!entry || !buf)
+		return -EINVAL;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
+		return -EIO;
+
+	str += sprintf(str, "0x%lx\n", var->DataSize);
+	return str - buf;
+}
+
+static ssize_t
+efivar_data_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+
+	if (!entry || !buf)
+		return -EINVAL;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
+		return -EIO;
+
+	memcpy(buf, var->Data, var->DataSize);
+	return var->DataSize;
+}
+/*
+ * We allow each variable to be edited via rewriting the
+ * entire efi variable structure.
+ */
+static ssize_t
+efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
+{
+	struct efi_variable *new_var, *var = &entry->var;
+	int err;
+
+	if (count != sizeof(struct efi_variable))
+		return -EINVAL;
+
+	new_var = (struct efi_variable *)buf;
+	/*
+	 * If only updating the variable data, then the name
+	 * and guid should remain the same
+	 */
+	if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) ||
+		efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) {
+		printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n");
+		return -EINVAL;
+	}
+
+	if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){
+		printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n");
+		return -EINVAL;
+	}
+
+	if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 ||
+	    efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) {
+		printk(KERN_ERR "efivars: Malformed variable content\n");
+		return -EINVAL;
+	}
+
+	memcpy(&entry->var, new_var, count);
+
+	err = efivar_entry_set(entry, new_var->Attributes,
+			       new_var->DataSize, new_var->Data, false);
+	if (err) {
+		printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err);
+		return -EIO;
+	}
+
+	return count;
+}
+
+static ssize_t
+efivar_show_raw(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+
+	if (!entry || !buf)
+		return 0;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &entry->var.Attributes,
+			     &entry->var.DataSize, entry->var.Data))
+		return -EIO;
+
+	memcpy(buf, var, sizeof(*var));
+
+	return sizeof(*var);
+}
+
+/*
+ * Generic read/write functions that call the specific functions of
+ * the attributes...
+ */
+static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr,
+				char *buf)
+{
+	struct efivar_entry *var = to_efivar_entry(kobj);
+	struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
+	ssize_t ret = -EIO;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (efivar_attr->show) {
+		ret = efivar_attr->show(var, buf);
+	}
+	return ret;
+}
+
+static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr,
+				const char *buf, size_t count)
+{
+	struct efivar_entry *var = to_efivar_entry(kobj);
+	struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
+	ssize_t ret = -EIO;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (efivar_attr->store)
+		ret = efivar_attr->store(var, buf, count);
+
+	return ret;
+}
+
+static const struct sysfs_ops efivar_attr_ops = {
+	.show = efivar_attr_show,
+	.store = efivar_attr_store,
+};
+
+static void efivar_release(struct kobject *kobj)
+{
+	struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj);
+	kfree(var);
+}
+
+static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL);
+static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL);
+static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL);
+static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL);
+static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw);
+
+static struct attribute *def_attrs[] = {
+	&efivar_attr_guid.attr,
+	&efivar_attr_size.attr,
+	&efivar_attr_attributes.attr,
+	&efivar_attr_data.attr,
+	&efivar_attr_raw_var.attr,
+	NULL,
+};
+
+static struct kobj_type efivar_ktype = {
+	.release = efivar_release,
+	.sysfs_ops = &efivar_attr_ops,
+	.default_attrs = def_attrs,
+};
+
+static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
+			     struct bin_attribute *bin_attr,
+			     char *buf, loff_t pos, size_t count)
+{
+	struct efi_variable *new_var = (struct efi_variable *)buf;
+	struct efivar_entry *new_entry;
+	int err;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 ||
+	    efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) {
+		printk(KERN_ERR "efivars: Malformed variable content\n");
+		return -EINVAL;
+	}
+
+	new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL);
+	if (!new_entry)
+		return -ENOMEM;
+
+	memcpy(&new_entry->var, new_var, sizeof(*new_var));
+
+	err = efivar_entry_set(new_entry, new_var->Attributes, new_var->DataSize,
+			       new_var->Data, &efivar_sysfs_list);
+	if (err) {
+		if (err == -EEXIST)
+			err = -EINVAL;
+		goto out;
+	}
+
+	if (efivar_create_sysfs_entry(new_entry)) {
+		printk(KERN_WARNING "efivars: failed to create sysfs entry.\n");
+		kfree(new_entry);
+	}
+	return count;
+
+out:
+	kfree(new_entry);
+	return err;
+}
+
+static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
+			     struct bin_attribute *bin_attr,
+			     char *buf, loff_t pos, size_t count)
+{
+	struct efi_variable *del_var = (struct efi_variable *)buf;
+	struct efivar_entry *entry;
+	int err = 0;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	efivar_entry_iter_begin();
+	entry = efivar_entry_find(del_var->VariableName, del_var->VendorGuid,
+				  &efivar_sysfs_list, true);
+	if (!entry)
+		err = -EINVAL;
+	else if (__efivar_entry_delete(entry))
+		err = -EIO;
+
+	efivar_entry_iter_end();
+
+	if (err)
+		return err;
+
+	efivar_unregister(entry);
+
+	/* It's dead Jim.... */
+	return count;
+}
+
+/**
+ * efivar_create_sysfs_entry - create a new entry in sysfs
+ * @new_var: efivar entry to create
+ *
+ * Returns 1 on failure, 0 on success
+ */
+static int
+efivar_create_sysfs_entry(struct efivar_entry *new_var)
+{
+	int i, short_name_size;
+	char *short_name;
+	unsigned long variable_name_size;
+	efi_char16_t *variable_name;
+
+	variable_name = new_var->var.VariableName;
+	variable_name_size = ucs2_strlen(variable_name) * sizeof(efi_char16_t);
+
+	/*
+	 * Length of the variable bytes in ASCII, plus the '-' separator,
+	 * plus the GUID, plus trailing NUL
+	 */
+	short_name_size = variable_name_size / sizeof(efi_char16_t)
+				+ 1 + EFI_VARIABLE_GUID_LEN + 1;
+
+	short_name = kzalloc(short_name_size, GFP_KERNEL);
+
+	if (!short_name)
+		return 1;
+
+	/* Convert Unicode to normal chars (assume top bits are 0),
+	   ala UTF-8 */
+	for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) {
+		short_name[i] = variable_name[i] & 0xFF;
+	}
+	/* This is ugly, but necessary to separate one vendor's
+	   private variables from another's.         */
+
+	*(short_name + strlen(short_name)) = '-';
+	efi_guid_unparse(&new_var->var.VendorGuid,
+			 short_name + strlen(short_name));
+
+	new_var->kobj.kset = efivars_kset;
+
+	i = kobject_init_and_add(&new_var->kobj, &efivar_ktype,
+				   NULL, "%s", short_name);
+	kfree(short_name);
+	if (i)
+		return 1;
+
+	kobject_uevent(&new_var->kobj, KOBJ_ADD);
+	efivar_entry_add(new_var, &efivar_sysfs_list);
+
+	return 0;
+}
+
+static int
+create_efivars_bin_attributes(void)
+{
+	struct bin_attribute *attr;
+	int error;
+
+	/* new_var */
+	attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+	if (!attr)
+		return -ENOMEM;
+
+	attr->attr.name = "new_var";
+	attr->attr.mode = 0200;
+	attr->write = efivar_create;
+	efivars_new_var = attr;
+
+	/* del_var */
+	attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+	if (!attr) {
+		error = -ENOMEM;
+		goto out_free;
+	}
+	attr->attr.name = "del_var";
+	attr->attr.mode = 0200;
+	attr->write = efivar_delete;
+	efivars_del_var = attr;
+
+	sysfs_bin_attr_init(efivars_new_var);
+	sysfs_bin_attr_init(efivars_del_var);
+
+	/* Register */
+	error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_new_var);
+	if (error) {
+		printk(KERN_ERR "efivars: unable to create new_var sysfs file"
+			" due to error %d\n", error);
+		goto out_free;
+	}
+
+	error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_del_var);
+	if (error) {
+		printk(KERN_ERR "efivars: unable to create del_var sysfs file"
+			" due to error %d\n", error);
+		sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var);
+		goto out_free;
+	}
+
+	return 0;
+out_free:
+	kfree(efivars_del_var);
+	efivars_del_var = NULL;
+	kfree(efivars_new_var);
+	efivars_new_var = NULL;
+	return error;
+}
+
+static int efivar_update_sysfs_entry(efi_char16_t *name, efi_guid_t vendor,
+				     unsigned long name_size, void *data)
+{
+	struct efivar_entry *entry = data;
+
+	if (efivar_entry_find(name, vendor, &efivar_sysfs_list, false))
+		return 0;
+
+	memcpy(entry->var.VariableName, name, name_size);
+	memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
+
+	return 1;
+}
+
+static void efivar_update_sysfs_entries(struct work_struct *work)
+{
+	struct efivar_entry *entry;
+	int err;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return;
+
+	/* Add new sysfs entries */
+	while (1) {
+		memset(entry, 0, sizeof(*entry));
+
+		err = efivar_init(efivar_update_sysfs_entry, entry,
+				  true, false, &efivar_sysfs_list);
+		if (!err)
+			break;
+
+		efivar_create_sysfs_entry(entry);
+	}
+
+	kfree(entry);
+}
+
+static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor,
+				  unsigned long name_size, void *data)
+{
+	struct efivar_entry *entry;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	memcpy(entry->var.VariableName, name, name_size);
+	memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
+
+	efivar_create_sysfs_entry(entry);
+
+	return 0;
+}
+
+static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data)
+{
+	efivar_entry_remove(entry);
+	efivar_unregister(entry);
+	return 0;
+}
+
+void efivars_sysfs_exit(void)
+{
+	/* Remove all entries and destroy */
+	__efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL, NULL);
+
+	if (efivars_new_var)
+		sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var);
+	if (efivars_del_var)
+		sysfs_remove_bin_file(&efivars_kset->kobj, efivars_del_var);
+	kfree(efivars_new_var);
+	kfree(efivars_del_var);
+	kset_unregister(efivars_kset);
+}
+
+int efivars_sysfs_init(void)
+{
+	struct kobject *parent_kobj = efivars_kobject();
+	int error = 0;
+
+	/* No efivars has been registered yet */
+	if (!parent_kobj)
+		return 0;
+
+	printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION,
+	       EFIVARS_DATE);
+
+	efivars_kset = kset_create_and_add("vars", NULL, parent_kobj);
+	if (!efivars_kset) {
+		printk(KERN_ERR "efivars: Subsystem registration failed.\n");
+		return -ENOMEM;
+	}
+
+	efivar_init(efivars_sysfs_callback, NULL, false,
+		    true, &efivar_sysfs_list);
+
+	error = create_efivars_bin_attributes();
+	if (error) {
+		efivars_sysfs_exit();
+		return error;
+	}
+
+	INIT_WORK(&efivar_work, efivar_update_sysfs_entries);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(efivars_sysfs_init);
+
+module_init(efivars_sysfs_init);
+module_exit(efivars_sysfs_exit);

drivers/firmware/efi/vars.c

@@ -0,0 +1,1041 @@
+/*
+ * Originally from efivars.c
+ *
+ * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
+ * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
+ *
+ *  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
+ *  (at your option) 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/capability.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/smp.h>
+#include <linux/efi.h>
+#include <linux/sysfs.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/ctype.h>
+#include <linux/ucs2_string.h>
+
+/* Private pointer to registered efivars */
+static struct efivars *__efivars;
+
+static bool efivar_wq_enabled = true;
+DECLARE_WORK(efivar_work, NULL);
+EXPORT_SYMBOL_GPL(efivar_work);
+
+static bool
+validate_device_path(struct efi_variable *var, int match, u8 *buffer,
+		     unsigned long len)
+{
+	struct efi_generic_dev_path *node;
+	int offset = 0;
+
+	node = (struct efi_generic_dev_path *)buffer;
+
+	if (len < sizeof(*node))
+		return false;
+
+	while (offset <= len - sizeof(*node) &&
+	       node->length >= sizeof(*node) &&
+		node->length <= len - offset) {
+		offset += node->length;
+
+		if ((node->type == EFI_DEV_END_PATH ||
+		     node->type == EFI_DEV_END_PATH2) &&
+		    node->sub_type == EFI_DEV_END_ENTIRE)
+			return true;
+
+		node = (struct efi_generic_dev_path *)(buffer + offset);
+	}
+
+	/*
+	 * If we're here then either node->length pointed past the end
+	 * of the buffer or we reached the end of the buffer without
+	 * finding a device path end node.
+	 */
+	return false;
+}
+
+static bool
+validate_boot_order(struct efi_variable *var, int match, u8 *buffer,
+		    unsigned long len)
+{
+	/* An array of 16-bit integers */
+	if ((len % 2) != 0)
+		return false;
+
+	return true;
+}
+
+static bool
+validate_load_option(struct efi_variable *var, int match, u8 *buffer,
+		     unsigned long len)
+{
+	u16 filepathlength;
+	int i, desclength = 0, namelen;
+
+	namelen = ucs2_strnlen(var->VariableName, sizeof(var->VariableName));
+
+	/* Either "Boot" or "Driver" followed by four digits of hex */
+	for (i = match; i < match+4; i++) {
+		if (var->VariableName[i] > 127 ||
+		    hex_to_bin(var->VariableName[i] & 0xff) < 0)
+			return true;
+	}
+
+	/* Reject it if there's 4 digits of hex and then further content */
+	if (namelen > match + 4)
+		return false;
+
+	/* A valid entry must be at least 8 bytes */
+	if (len < 8)
+		return false;
+
+	filepathlength = buffer[4] | buffer[5] << 8;
+
+	/*
+	 * There's no stored length for the description, so it has to be
+	 * found by hand
+	 */
+	desclength = ucs2_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2;
+
+	/* Each boot entry must have a descriptor */
+	if (!desclength)
+		return false;
+
+	/*
+	 * If the sum of the length of the description, the claimed filepath
+	 * length and the original header are greater than the length of the
+	 * variable, it's malformed
+	 */
+	if ((desclength + filepathlength + 6) > len)
+		return false;
+
+	/*
+	 * And, finally, check the filepath
+	 */
+	return validate_device_path(var, match, buffer + desclength + 6,
+				    filepathlength);
+}
+
+static bool
+validate_uint16(struct efi_variable *var, int match, u8 *buffer,
+		unsigned long len)
+{
+	/* A single 16-bit integer */
+	if (len != 2)
+		return false;
+
+	return true;
+}
+
+static bool
+validate_ascii_string(struct efi_variable *var, int match, u8 *buffer,
+		      unsigned long len)
+{
+	int i;
+
+	for (i = 0; i < len; i++) {
+		if (buffer[i] > 127)
+			return false;
+
+		if (buffer[i] == 0)
+			return true;
+	}
+
+	return false;
+}
+
+struct variable_validate {
+	char *name;
+	bool (*validate)(struct efi_variable *var, int match, u8 *data,
+			 unsigned long len);
+};
+
+static const struct variable_validate variable_validate[] = {
+	{ "BootNext", validate_uint16 },
+	{ "BootOrder", validate_boot_order },
+	{ "DriverOrder", validate_boot_order },
+	{ "Boot*", validate_load_option },
+	{ "Driver*", validate_load_option },
+	{ "ConIn", validate_device_path },
+	{ "ConInDev", validate_device_path },
+	{ "ConOut", validate_device_path },
+	{ "ConOutDev", validate_device_path },
+	{ "ErrOut", validate_device_path },
+	{ "ErrOutDev", validate_device_path },
+	{ "Timeout", validate_uint16 },
+	{ "Lang", validate_ascii_string },
+	{ "PlatformLang", validate_ascii_string },
+	{ "", NULL },
+};
+
+bool
+efivar_validate(struct efi_variable *var, u8 *data, unsigned long len)
+{
+	int i;
+	u16 *unicode_name = var->VariableName;
+
+	for (i = 0; variable_validate[i].validate != NULL; i++) {
+		const char *name = variable_validate[i].name;
+		int match;
+
+		for (match = 0; ; match++) {
+			char c = name[match];
+			u16 u = unicode_name[match];
+
+			/* All special variables are plain ascii */
+			if (u > 127)
+				return true;
+
+			/* Wildcard in the matching name means we've matched */
+			if (c == '*')
+				return variable_validate[i].validate(var,
+							     match, data, len);
+
+			/* Case sensitive match */
+			if (c != u)
+				break;
+
+			/* Reached the end of the string while matching */
+			if (!c)
+				return variable_validate[i].validate(var,
+							     match, data, len);
+		}
+	}
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(efivar_validate);
+
+static efi_status_t
+check_var_size(u32 attributes, unsigned long size)
+{
+	const struct efivar_operations *fops = __efivars->ops;
+
+	if (!fops->query_variable_store)
+		return EFI_UNSUPPORTED;
+
+	return fops->query_variable_store(attributes, size);
+}
+
+static int efi_status_to_err(efi_status_t status)
+{
+	int err;
+
+	switch (status) {
+	case EFI_SUCCESS:
+		err = 0;
+		break;
+	case EFI_INVALID_PARAMETER:
+		err = -EINVAL;
+		break;
+	case EFI_OUT_OF_RESOURCES:
+		err = -ENOSPC;
+		break;
+	case EFI_DEVICE_ERROR:
+		err = -EIO;
+		break;
+	case EFI_WRITE_PROTECTED:
+		err = -EROFS;
+		break;
+	case EFI_SECURITY_VIOLATION:
+		err = -EACCES;
+		break;
+	case EFI_NOT_FOUND:
+		err = -ENOENT;
+		break;
+	default:
+		err = -EINVAL;
+	}
+
+	return err;
+}
+
+static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor,
+				struct list_head *head)
+{
+	struct efivar_entry *entry, *n;
+	unsigned long strsize1, strsize2;
+	bool found = false;
+
+	strsize1 = ucs2_strsize(variable_name, 1024);
+	list_for_each_entry_safe(entry, n, head, list) {
+		strsize2 = ucs2_strsize(entry->var.VariableName, 1024);
+		if (strsize1 == strsize2 &&
+			!memcmp(variable_name, &(entry->var.VariableName),
+				strsize2) &&
+			!efi_guidcmp(entry->var.VendorGuid,
+				*vendor)) {
+			found = true;
+			break;
+		}
+	}
+	return found;
+}
+
+/*
+ * Returns the size of variable_name, in bytes, including the
+ * terminating NULL character, or variable_name_size if no NULL
+ * character is found among the first variable_name_size bytes.
+ */
+static unsigned long var_name_strnsize(efi_char16_t *variable_name,
+				       unsigned long variable_name_size)
+{
+	unsigned long len;
+	efi_char16_t c;
+
+	/*
+	 * The variable name is, by definition, a NULL-terminated
+	 * string, so make absolutely sure that variable_name_size is
+	 * the value we expect it to be. If not, return the real size.
+	 */
+	for (len = 2; len <= variable_name_size; len += sizeof(c)) {
+		c = variable_name[(len / sizeof(c)) - 1];
+		if (!c)
+			break;
+	}
+
+	return min(len, variable_name_size);
+}
+
+/*
+ * Print a warning when duplicate EFI variables are encountered and
+ * disable the sysfs workqueue since the firmware is buggy.
+ */
+static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid,
+			     unsigned long len16)
+{
+	size_t i, len8 = len16 / sizeof(efi_char16_t);
+	char *s8;
+
+	/*
+	 * Disable the workqueue since the algorithm it uses for
+	 * detecting new variables won't work with this buggy
+	 * implementation of GetNextVariableName().
+	 */
+	efivar_wq_enabled = false;
+
+	s8 = kzalloc(len8, GFP_KERNEL);
+	if (!s8)
+		return;
+
+	for (i = 0; i < len8; i++)
+		s8[i] = s16[i];
+
+	printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n",
+	       s8, vendor_guid);
+	kfree(s8);
+}
+
+/**
+ * efivar_init - build the initial list of EFI variables
+ * @func: callback function to invoke for every variable
+ * @data: function-specific data to pass to @func
+ * @atomic: do we need to execute the @func-loop atomically?
+ * @duplicates: error if we encounter duplicates on @head?
+ * @head: initialised head of variable list
+ *
+ * Get every EFI variable from the firmware and invoke @func. @func
+ * should call efivar_entry_add() to build the list of variables.
+ *
+ * Returns 0 on success, or a kernel error code on failure.
+ */
+int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *),
+		void *data, bool atomic, bool duplicates,
+		struct list_head *head)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	unsigned long variable_name_size = 1024;
+	efi_char16_t *variable_name;
+	efi_status_t status;
+	efi_guid_t vendor_guid;
+	int err = 0;
+
+	variable_name = kzalloc(variable_name_size, GFP_KERNEL);
+	if (!variable_name) {
+		printk(KERN_ERR "efivars: Memory allocation failed.\n");
+		return -ENOMEM;
+	}
+
+	spin_lock_irq(&__efivars->lock);
+
+	/*
+	 * Per EFI spec, the maximum storage allocated for both
+	 * the variable name and variable data is 1024 bytes.
+	 */
+
+	do {
+		variable_name_size = 1024;
+
+		status = ops->get_next_variable(&variable_name_size,
+						variable_name,
+						&vendor_guid);
+		switch (status) {
+		case EFI_SUCCESS:
+			if (!atomic)
+				spin_unlock_irq(&__efivars->lock);
+
+			variable_name_size = var_name_strnsize(variable_name,
+							       variable_name_size);
+
+			/*
+			 * Some firmware implementations return the
+			 * same variable name on multiple calls to
+			 * get_next_variable(). Terminate the loop
+			 * immediately as there is no guarantee that
+			 * we'll ever see a different variable name,
+			 * and may end up looping here forever.
+			 */
+			if (duplicates &&
+			    variable_is_present(variable_name, &vendor_guid, head)) {
+				dup_variable_bug(variable_name, &vendor_guid,
+						 variable_name_size);
+				if (!atomic)
+					spin_lock_irq(&__efivars->lock);
+
+				status = EFI_NOT_FOUND;
+				break;
+			}
+
+			err = func(variable_name, vendor_guid, variable_name_size, data);
+			if (err)
+				status = EFI_NOT_FOUND;
+
+			if (!atomic)
+				spin_lock_irq(&__efivars->lock);
+
+			break;
+		case EFI_NOT_FOUND:
+			break;
+		default:
+			printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n",
+				status);
+			status = EFI_NOT_FOUND;
+			break;
+		}
+
+	} while (status != EFI_NOT_FOUND);
+
+	spin_unlock_irq(&__efivars->lock);
+
+	kfree(variable_name);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(efivar_init);
+
+/**
+ * efivar_entry_add - add entry to variable list
+ * @entry: entry to add to list
+ * @head: list head
+ */
+void efivar_entry_add(struct efivar_entry *entry, struct list_head *head)
+{
+	spin_lock_irq(&__efivars->lock);
+	list_add(&entry->list, head);
+	spin_unlock_irq(&__efivars->lock);
+}
+EXPORT_SYMBOL_GPL(efivar_entry_add);
+
+/**
+ * efivar_entry_remove - remove entry from variable list
+ * @entry: entry to remove from list
+ */
+void efivar_entry_remove(struct efivar_entry *entry)
+{
+	spin_lock_irq(&__efivars->lock);
+	list_del(&entry->list);
+	spin_unlock_irq(&__efivars->lock);
+}
+EXPORT_SYMBOL_GPL(efivar_entry_remove);
+
+/*
+ * efivar_entry_list_del_unlock - remove entry from variable list
+ * @entry: entry to remove
+ *
+ * Remove @entry from the variable list and release the list lock.
+ *
+ * NOTE: slightly weird locking semantics here - we expect to be
+ * called with the efivars lock already held, and we release it before
+ * returning. This is because this function is usually called after
+ * set_variable() while the lock is still held.
+ */
+static void efivar_entry_list_del_unlock(struct efivar_entry *entry)
+{
+	WARN_ON(!spin_is_locked(&__efivars->lock));
+
+	list_del(&entry->list);
+	spin_unlock_irq(&__efivars->lock);
+}
+
+/**
+ * __efivar_entry_delete - delete an EFI variable
+ * @entry: entry containing EFI variable to delete
+ *
+ * Delete the variable from the firmware but leave @entry on the
+ * variable list.
+ *
+ * This function differs from efivar_entry_delete() because it does
+ * not remove @entry from the variable list. Also, it is safe to be
+ * called from within a efivar_entry_iter_begin() and
+ * efivar_entry_iter_end() region, unlike efivar_entry_delete().
+ *
+ * Returns 0 on success, or a converted EFI status code if
+ * set_variable() fails.
+ */
+int __efivar_entry_delete(struct efivar_entry *entry)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	efi_status_t status;
+
+	WARN_ON(!spin_is_locked(&__efivars->lock));
+
+	status = ops->set_variable(entry->var.VariableName,
+				   &entry->var.VendorGuid,
+				   0, 0, NULL);
+
+	return efi_status_to_err(status);
+}
+EXPORT_SYMBOL_GPL(__efivar_entry_delete);
+
+/**
+ * efivar_entry_delete - delete variable and remove entry from list
+ * @entry: entry containing variable to delete
+ *
+ * Delete the variable from the firmware and remove @entry from the
+ * variable list. It is the caller's responsibility to free @entry
+ * once we return.
+ *
+ * Returns 0 on success, or a converted EFI status code if
+ * set_variable() fails.
+ */
+int efivar_entry_delete(struct efivar_entry *entry)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	efi_status_t status;
+
+	spin_lock_irq(&__efivars->lock);
+	status = ops->set_variable(entry->var.VariableName,
+				   &entry->var.VendorGuid,
+				   0, 0, NULL);
+	if (!(status == EFI_SUCCESS || status == EFI_NOT_FOUND)) {
+		spin_unlock_irq(&__efivars->lock);
+		return efi_status_to_err(status);
+	}
+
+	efivar_entry_list_del_unlock(entry);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(efivar_entry_delete);
+
+/**
+ * efivar_entry_set - call set_variable()
+ * @entry: entry containing the EFI variable to write
+ * @attributes: variable attributes
+ * @size: size of @data buffer
+ * @data: buffer containing variable data
+ * @head: head of variable list
+ *
+ * Calls set_variable() for an EFI variable. If creating a new EFI
+ * variable, this function is usually followed by efivar_entry_add().
+ *
+ * Before writing the variable, the remaining EFI variable storage
+ * space is checked to ensure there is enough room available.
+ *
+ * If @head is not NULL a lookup is performed to determine whether
+ * the entry is already on the list.
+ *
+ * Returns 0 on success, -EEXIST if a lookup is performed and the entry
+ * already exists on the list, or a converted EFI status code if
+ * set_variable() fails.
+ */
+int efivar_entry_set(struct efivar_entry *entry, u32 attributes,
+		     unsigned long size, void *data, struct list_head *head)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	efi_status_t status;
+	efi_char16_t *name = entry->var.VariableName;
+	efi_guid_t vendor = entry->var.VendorGuid;
+
+	spin_lock_irq(&__efivars->lock);
+
+	if (head && efivar_entry_find(name, vendor, head, false)) {
+		spin_unlock_irq(&__efivars->lock);
+		return -EEXIST;
+	}
+
+	status = check_var_size(attributes, size + ucs2_strsize(name, 1024));
+	if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED)
+		status = ops->set_variable(name, &vendor,
+					   attributes, size, data);
+
+	spin_unlock_irq(&__efivars->lock);
+
+	return efi_status_to_err(status);
+
+}
+EXPORT_SYMBOL_GPL(efivar_entry_set);
+
+/**
+ * efivar_entry_set_safe - call set_variable() if enough space in firmware
+ * @name: buffer containing the variable name
+ * @vendor: variable vendor guid
+ * @attributes: variable attributes
+ * @block: can we block in this context?
+ * @size: size of @data buffer
+ * @data: buffer containing variable data
+ *
+ * Ensures there is enough free storage in the firmware for this variable, and
+ * if so, calls set_variable(). If creating a new EFI variable, this function
+ * is usually followed by efivar_entry_add().
+ *
+ * Returns 0 on success, -ENOSPC if the firmware does not have enough
+ * space for set_variable() to succeed, or a converted EFI status code
+ * if set_variable() fails.
+ */
+int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes,
+			  bool block, unsigned long size, void *data)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	unsigned long flags;
+	efi_status_t status;
+
+	if (!ops->query_variable_store)
+		return -ENOSYS;
+
+	if (!block) {
+		if (!spin_trylock_irqsave(&__efivars->lock, flags))
+			return -EBUSY;
+	} else {
+		spin_lock_irqsave(&__efivars->lock, flags);
+	}
+
+	status = check_var_size(attributes, size + ucs2_strsize(name, 1024));
+	if (status != EFI_SUCCESS) {
+		spin_unlock_irqrestore(&__efivars->lock, flags);
+		return -ENOSPC;
+	}
+
+	status = ops->set_variable(name, &vendor, attributes, size, data);
+
+	spin_unlock_irqrestore(&__efivars->lock, flags);
+
+	return efi_status_to_err(status);
+}
+EXPORT_SYMBOL_GPL(efivar_entry_set_safe);
+
+/**
+ * efivar_entry_find - search for an entry
+ * @name: the EFI variable name
+ * @guid: the EFI variable vendor's guid
+ * @head: head of the variable list
+ * @remove: should we remove the entry from the list?
+ *
+ * Search for an entry on the variable list that has the EFI variable
+ * name @name and vendor guid @guid. If an entry is found on the list
+ * and @remove is true, the entry is removed from the list.
+ *
+ * The caller MUST call efivar_entry_iter_begin() and
+ * efivar_entry_iter_end() before and after the invocation of this
+ * function, respectively.
+ *
+ * Returns the entry if found on the list, %NULL otherwise.
+ */
+struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid,
+				       struct list_head *head, bool remove)
+{
+	struct efivar_entry *entry, *n;
+	int strsize1, strsize2;
+	bool found = false;
+
+	WARN_ON(!spin_is_locked(&__efivars->lock));
+
+	list_for_each_entry_safe(entry, n, head, list) {
+		strsize1 = ucs2_strsize(name, 1024);
+		strsize2 = ucs2_strsize(entry->var.VariableName, 1024);
+		if (strsize1 == strsize2 &&
+		    !memcmp(name, &(entry->var.VariableName), strsize1) &&
+		    !efi_guidcmp(guid, entry->var.VendorGuid)) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found)
+		return NULL;
+
+	if (remove)
+		list_del(&entry->list);
+
+	return entry;
+}
+EXPORT_SYMBOL_GPL(efivar_entry_find);
+
+/**
+ * efivar_entry_size - obtain the size of a variable
+ * @entry: entry for this variable
+ * @size: location to store the variable's size
+ */
+int efivar_entry_size(struct efivar_entry *entry, unsigned long *size)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	efi_status_t status;
+
+	*size = 0;
+
+	spin_lock_irq(&__efivars->lock);
+	status = ops->get_variable(entry->var.VariableName,
+				   &entry->var.VendorGuid, NULL, size, NULL);
+	spin_unlock_irq(&__efivars->lock);
+
+	if (status != EFI_BUFFER_TOO_SMALL)
+		return efi_status_to_err(status);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(efivar_entry_size);
+
+/**
+ * __efivar_entry_get - call get_variable()
+ * @entry: read data for this variable
+ * @attributes: variable attributes
+ * @size: size of @data buffer
+ * @data: buffer to store variable data
+ *
+ * The caller MUST call efivar_entry_iter_begin() and
+ * efivar_entry_iter_end() before and after the invocation of this
+ * function, respectively.
+ */
+int __efivar_entry_get(struct efivar_entry *entry, u32 *attributes,
+		       unsigned long *size, void *data)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	efi_status_t status;
+
+	WARN_ON(!spin_is_locked(&__efivars->lock));
+
+	status = ops->get_variable(entry->var.VariableName,
+				   &entry->var.VendorGuid,
+				   attributes, size, data);
+
+	return efi_status_to_err(status);
+}
+EXPORT_SYMBOL_GPL(__efivar_entry_get);
+
+/**
+ * efivar_entry_get - call get_variable()
+ * @entry: read data for this variable
+ * @attributes: variable attributes
+ * @size: size of @data buffer
+ * @data: buffer to store variable data
+ */
+int efivar_entry_get(struct efivar_entry *entry, u32 *attributes,
+		     unsigned long *size, void *data)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	efi_status_t status;
+
+	spin_lock_irq(&__efivars->lock);
+	status = ops->get_variable(entry->var.VariableName,
+				   &entry->var.VendorGuid,
+				   attributes, size, data);
+	spin_unlock_irq(&__efivars->lock);
+
+	return efi_status_to_err(status);
+}
+EXPORT_SYMBOL_GPL(efivar_entry_get);
+
+/**
+ * efivar_entry_set_get_size - call set_variable() and get new size (atomic)
+ * @entry: entry containing variable to set and get
+ * @attributes: attributes of variable to be written
+ * @size: size of data buffer
+ * @data: buffer containing data to write
+ * @set: did the set_variable() call succeed?
+ *
+ * This is a pretty special (complex) function. See efivarfs_file_write().
+ *
+ * Atomically call set_variable() for @entry and if the call is
+ * successful, return the new size of the variable from get_variable()
+ * in @size. The success of set_variable() is indicated by @set.
+ *
+ * Returns 0 on success, -EINVAL if the variable data is invalid,
+ * -ENOSPC if the firmware does not have enough available space, or a
+ * converted EFI status code if either of set_variable() or
+ * get_variable() fail.
+ *
+ * If the EFI variable does not exist when calling set_variable()
+ * (EFI_NOT_FOUND), @entry is removed from the variable list.
+ */
+int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes,
+			      unsigned long *size, void *data, bool *set)
+{
+	const struct efivar_operations *ops = __efivars->ops;
+	efi_char16_t *name = entry->var.VariableName;
+	efi_guid_t *vendor = &entry->var.VendorGuid;
+	efi_status_t status;
+	int err;
+
+	*set = false;
+
+	if (efivar_validate(&entry->var, data, *size) == false)
+		return -EINVAL;
+
+	/*
+	 * The lock here protects the get_variable call, the conditional
+	 * set_variable call, and removal of the variable from the efivars
+	 * list (in the case of an authenticated delete).
+	 */
+	spin_lock_irq(&__efivars->lock);
+
+	/*
+	 * Ensure that the available space hasn't shrunk below the safe level
+	 */
+	status = check_var_size(attributes, *size + ucs2_strsize(name, 1024));
+	if (status != EFI_SUCCESS) {
+		if (status != EFI_UNSUPPORTED) {
+			err = efi_status_to_err(status);
+			goto out;
+		}
+
+		if (*size > 65536) {
+			err = -ENOSPC;
+			goto out;
+		}
+	}
+
+	status = ops->set_variable(name, vendor, attributes, *size, data);
+	if (status != EFI_SUCCESS) {
+		err = efi_status_to_err(status);
+		goto out;
+	}
+
+	*set = true;
+
+	/*
+	 * Writing to the variable may have caused a change in size (which
+	 * could either be an append or an overwrite), or the variable to be
+	 * deleted. Perform a GetVariable() so we can tell what actually
+	 * happened.
+	 */
+	*size = 0;
+	status = ops->get_variable(entry->var.VariableName,
+				   &entry->var.VendorGuid,
+				   NULL, size, NULL);
+
+	if (status == EFI_NOT_FOUND)
+		efivar_entry_list_del_unlock(entry);
+	else
+		spin_unlock_irq(&__efivars->lock);
+
+	if (status && status != EFI_BUFFER_TOO_SMALL)
+		return efi_status_to_err(status);
+
+	return 0;
+
+out:
+	spin_unlock_irq(&__efivars->lock);
+	return err;
+
+}
+EXPORT_SYMBOL_GPL(efivar_entry_set_get_size);
+
+/**
+ * efivar_entry_iter_begin - begin iterating the variable list
+ *
+ * Lock the variable list to prevent entry insertion and removal until
+ * efivar_entry_iter_end() is called. This function is usually used in
+ * conjunction with __efivar_entry_iter() or efivar_entry_iter().
+ */
+void efivar_entry_iter_begin(void)
+{
+	spin_lock_irq(&__efivars->lock);
+}
+EXPORT_SYMBOL_GPL(efivar_entry_iter_begin);
+
+/**
+ * efivar_entry_iter_end - finish iterating the variable list
+ *
+ * Unlock the variable list and allow modifications to the list again.
+ */
+void efivar_entry_iter_end(void)
+{
+	spin_unlock_irq(&__efivars->lock);
+}
+EXPORT_SYMBOL_GPL(efivar_entry_iter_end);
+
+/**
+ * __efivar_entry_iter - iterate over variable list
+ * @func: callback function
+ * @head: head of the variable list
+ * @data: function-specific data to pass to callback
+ * @prev: entry to begin iterating from
+ *
+ * Iterate over the list of EFI variables and call @func with every
+ * entry on the list. It is safe for @func to remove entries in the
+ * list via efivar_entry_delete().
+ *
+ * You MUST call efivar_enter_iter_begin() before this function, and
+ * efivar_entry_iter_end() afterwards.
+ *
+ * It is possible to begin iteration from an arbitrary entry within
+ * the list by passing @prev. @prev is updated on return to point to
+ * the last entry passed to @func. To begin iterating from the
+ * beginning of the list @prev must be %NULL.
+ *
+ * The restrictions for @func are the same as documented for
+ * efivar_entry_iter().
+ */
+int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *),
+			struct list_head *head, void *data,
+			struct efivar_entry **prev)
+{
+	struct efivar_entry *entry, *n;
+	int err = 0;
+
+	if (!prev || !*prev) {
+		list_for_each_entry_safe(entry, n, head, list) {
+			err = func(entry, data);
+			if (err)
+				break;
+		}
+
+		if (prev)
+			*prev = entry;
+
+		return err;
+	}
+
+
+	list_for_each_entry_safe_continue((*prev), n, head, list) {
+		err = func(*prev, data);
+		if (err)
+			break;
+	}
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(__efivar_entry_iter);
+
+/**
+ * efivar_entry_iter - iterate over variable list
+ * @func: callback function
+ * @head: head of variable list
+ * @data: function-specific data to pass to callback
+ *
+ * Iterate over the list of EFI variables and call @func with every
+ * entry on the list. It is safe for @func to remove entries in the
+ * list via efivar_entry_delete() while iterating.
+ *
+ * Some notes for the callback function:
+ *  - a non-zero return value indicates an error and terminates the loop
+ *  - @func is called from atomic context
+ */
+int efivar_entry_iter(int (*func)(struct efivar_entry *, void *),
+		      struct list_head *head, void *data)
+{
+	int err = 0;
+
+	efivar_entry_iter_begin();
+	err = __efivar_entry_iter(func, head, data, NULL);
+	efivar_entry_iter_end();
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(efivar_entry_iter);
+
+/**
+ * efivars_kobject - get the kobject for the registered efivars
+ *
+ * If efivars_register() has not been called we return NULL,
+ * otherwise return the kobject used at registration time.
+ */
+struct kobject *efivars_kobject(void)
+{
+	if (!__efivars)
+		return NULL;
+
+	return __efivars->kobject;
+}
+EXPORT_SYMBOL_GPL(efivars_kobject);
+
+/**
+ * efivar_run_worker - schedule the efivar worker thread
+ */
+void efivar_run_worker(void)
+{
+	if (efivar_wq_enabled)
+		schedule_work(&efivar_work);
+}
+EXPORT_SYMBOL_GPL(efivar_run_worker);
+
+/**
+ * efivars_register - register an efivars
+ * @efivars: efivars to register
+ * @ops: efivars operations
+ * @kobject: @efivars-specific kobject
+ *
+ * Only a single efivars can be registered at any time.
+ */
+int efivars_register(struct efivars *efivars,
+		     const struct efivar_operations *ops,
+		     struct kobject *kobject)
+{
+	spin_lock_init(&efivars->lock);
+	efivars->ops = ops;
+	efivars->kobject = kobject;
+
+	__efivars = efivars;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(efivars_register);
+
+/**
+ * efivars_unregister - unregister an efivars
+ * @efivars: efivars to unregister
+ *
+ * The caller must have already removed every entry from the list,
+ * failure to do so is an error.
+ */
+int efivars_unregister(struct efivars *efivars)
+{
+	int rv;
+
+	if (!__efivars) {
+		printk(KERN_ERR "efivars not registered\n");
+		rv = -EINVAL;
+		goto out;
+	}
+
+	if (__efivars != efivars) {
+		rv = -EINVAL;
+		goto out;
+	}
+
+	__efivars = NULL;
+
+	rv = 0;
+out:
+	return rv;
+}
+EXPORT_SYMBOL_GPL(efivars_unregister);

drivers/firmware/efivars.c

@@ -1,2117 +0,0 @@
-/*
- * EFI Variables - efivars.c
- *
- * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
- * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
- *
- * This code takes all variables accessible from EFI runtime and
- *  exports them via sysfs
- *
- *  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
- *  (at your option) 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
- * Changelog:
- *
- *  17 May 2004 - Matt Domsch <Matt_Domsch@dell.com>
- *   remove check for efi_enabled in exit
- *   add MODULE_VERSION
- *
- *  26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com>
- *   minor bug fixes
- *
- *  21 Apr 2004 - Matt Tolentino <matthew.e.tolentino@intel.com)
- *   converted driver to export variable information via sysfs
- *   and moved to drivers/firmware directory
- *   bumped revision number to v0.07 to reflect conversion & move
- *
- *  10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com>
- *   fix locking per Peter Chubb's findings
- *
- *  25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com>
- *   move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_unparse()
- *
- *  12 Feb 2002 - Matt Domsch <Matt_Domsch@dell.com>
- *   use list_for_each_safe when deleting vars.
- *   remove ifdef CONFIG_SMP around include <linux/smp.h>
- *   v0.04 release to linux-ia64@linuxia64.org
- *
- *  20 April 2001 - Matt Domsch <Matt_Domsch@dell.com>
- *   Moved vars from /proc/efi to /proc/efi/vars, and made
- *   efi.c own the /proc/efi directory.
- *   v0.03 release to linux-ia64@linuxia64.org
- *
- *  26 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
- *   At the request of Stephane, moved ownership of /proc/efi
- *   to efi.c, and now efivars lives under /proc/efi/vars.
- *
- *  12 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
- *   Feedback received from Stephane Eranian incorporated.
- *   efivar_write() checks copy_from_user() return value.
- *   efivar_read/write() returns proper errno.
- *   v0.02 release to linux-ia64@linuxia64.org
- *
- *  26 February 2001 - Matt Domsch <Matt_Domsch@dell.com>
- *   v0.01 release to linux-ia64@linuxia64.org
- */
-
-#include <linux/capability.h>
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/mm.h>
-#include <linux/module.h>
-#include <linux/string.h>
-#include <linux/smp.h>
-#include <linux/efi.h>
-#include <linux/sysfs.h>
-#include <linux/kobject.h>
-#include <linux/device.h>
-#include <linux/slab.h>
-#include <linux/pstore.h>
-#include <linux/ctype.h>
-#include <linux/ucs2_string.h>
-
-#include <linux/fs.h>
-#include <linux/ramfs.h>
-#include <linux/pagemap.h>
-
-#include <asm/uaccess.h>
-
-#define EFIVARS_VERSION "0.08"
-#define EFIVARS_DATE "2004-May-17"
-
-MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
-MODULE_DESCRIPTION("sysfs interface to EFI Variables");
-MODULE_LICENSE("GPL");
-MODULE_VERSION(EFIVARS_VERSION);
-
-#define DUMP_NAME_LEN 52
-
-/*
- * Length of a GUID string (strlen("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee"))
- * not including trailing NUL
- */
-#define GUID_LEN 36
-
-static bool efivars_pstore_disable =
-	IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE);
-
-module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644);
-
-/*
- * The maximum size of VariableName + Data = 1024
- * Therefore, it's reasonable to save that much
- * space in each part of the structure,
- * and we use a page for reading/writing.
- */
-
-struct efi_variable {
-	efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
-	efi_guid_t    VendorGuid;
-	unsigned long DataSize;
-	__u8          Data[1024];
-	efi_status_t  Status;
-	__u32         Attributes;
-} __attribute__((packed));
-
-struct efivar_entry {
-	struct efivars *efivars;
-	struct efi_variable var;
-	struct list_head list;
-	struct kobject kobj;
-};
-
-struct efivar_attribute {
-	struct attribute attr;
-	ssize_t (*show) (struct efivar_entry *entry, char *buf);
-	ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count);
-};
-
-static struct efivars __efivars;
-static struct efivar_operations ops;
-
-#define PSTORE_EFI_ATTRIBUTES \
-	(EFI_VARIABLE_NON_VOLATILE | \
-	 EFI_VARIABLE_BOOTSERVICE_ACCESS | \
-	 EFI_VARIABLE_RUNTIME_ACCESS)
-
-#define EFIVAR_ATTR(_name, _mode, _show, _store) \
-struct efivar_attribute efivar_attr_##_name = { \
-	.attr = {.name = __stringify(_name), .mode = _mode}, \
-	.show = _show, \
-	.store = _store, \
-};
-
-#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr)
-#define to_efivar_entry(obj)  container_of(obj, struct efivar_entry, kobj)
-
-/*
- * Prototype for sysfs creation function
- */
-static int
-efivar_create_sysfs_entry(struct efivars *efivars,
-			  unsigned long variable_name_size,
-			  efi_char16_t *variable_name,
-			  efi_guid_t *vendor_guid);
-
-/*
- * Prototype for workqueue functions updating sysfs entry
- */
-
-static void efivar_update_sysfs_entries(struct work_struct *);
-static DECLARE_WORK(efivar_work, efivar_update_sysfs_entries);
-static bool efivar_wq_enabled = true;
-
-static bool
-validate_device_path(struct efi_variable *var, int match, u8 *buffer,
-		     unsigned long len)
-{
-	struct efi_generic_dev_path *node;
-	int offset = 0;
-
-	node = (struct efi_generic_dev_path *)buffer;
-
-	if (len < sizeof(*node))
-		return false;
-
-	while (offset <= len - sizeof(*node) &&
-	       node->length >= sizeof(*node) &&
-		node->length <= len - offset) {
-		offset += node->length;
-
-		if ((node->type == EFI_DEV_END_PATH ||
-		     node->type == EFI_DEV_END_PATH2) &&
-		    node->sub_type == EFI_DEV_END_ENTIRE)
-			return true;
-
-		node = (struct efi_generic_dev_path *)(buffer + offset);
-	}
-
-	/*
-	 * If we're here then either node->length pointed past the end
-	 * of the buffer or we reached the end of the buffer without
-	 * finding a device path end node.
-	 */
-	return false;
-}
-
-static bool
-validate_boot_order(struct efi_variable *var, int match, u8 *buffer,
-		    unsigned long len)
-{
-	/* An array of 16-bit integers */
-	if ((len % 2) != 0)
-		return false;
-
-	return true;
-}
-
-static bool
-validate_load_option(struct efi_variable *var, int match, u8 *buffer,
-		     unsigned long len)
-{
-	u16 filepathlength;
-	int i, desclength = 0, namelen;
-
-	namelen = ucs2_strnlen(var->VariableName, sizeof(var->VariableName));
-
-	/* Either "Boot" or "Driver" followed by four digits of hex */
-	for (i = match; i < match+4; i++) {
-		if (var->VariableName[i] > 127 ||
-		    hex_to_bin(var->VariableName[i] & 0xff) < 0)
-			return true;
-	}
-
-	/* Reject it if there's 4 digits of hex and then further content */
-	if (namelen > match + 4)
-		return false;
-
-	/* A valid entry must be at least 8 bytes */
-	if (len < 8)
-		return false;
-
-	filepathlength = buffer[4] | buffer[5] << 8;
-
-	/*
-	 * There's no stored length for the description, so it has to be
-	 * found by hand
-	 */
-	desclength = ucs2_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2;
-
-	/* Each boot entry must have a descriptor */
-	if (!desclength)
-		return false;
-
-	/*
-	 * If the sum of the length of the description, the claimed filepath
-	 * length and the original header are greater than the length of the
-	 * variable, it's malformed
-	 */
-	if ((desclength + filepathlength + 6) > len)
-		return false;
-
-	/*
-	 * And, finally, check the filepath
-	 */
-	return validate_device_path(var, match, buffer + desclength + 6,
-				    filepathlength);
-}
-
-static bool
-validate_uint16(struct efi_variable *var, int match, u8 *buffer,
-		unsigned long len)
-{
-	/* A single 16-bit integer */
-	if (len != 2)
-		return false;
-
-	return true;
-}
-
-static bool
-validate_ascii_string(struct efi_variable *var, int match, u8 *buffer,
-		      unsigned long len)
-{
-	int i;
-
-	for (i = 0; i < len; i++) {
-		if (buffer[i] > 127)
-			return false;
-
-		if (buffer[i] == 0)
-			return true;
-	}
-
-	return false;
-}
-
-struct variable_validate {
-	char *name;
-	bool (*validate)(struct efi_variable *var, int match, u8 *data,
-			 unsigned long len);
-};
-
-static const struct variable_validate variable_validate[] = {
-	{ "BootNext", validate_uint16 },
-	{ "BootOrder", validate_boot_order },
-	{ "DriverOrder", validate_boot_order },
-	{ "Boot*", validate_load_option },
-	{ "Driver*", validate_load_option },
-	{ "ConIn", validate_device_path },
-	{ "ConInDev", validate_device_path },
-	{ "ConOut", validate_device_path },
-	{ "ConOutDev", validate_device_path },
-	{ "ErrOut", validate_device_path },
-	{ "ErrOutDev", validate_device_path },
-	{ "Timeout", validate_uint16 },
-	{ "Lang", validate_ascii_string },
-	{ "PlatformLang", validate_ascii_string },
-	{ "", NULL },
-};
-
-static bool
-validate_var(struct efi_variable *var, u8 *data, unsigned long len)
-{
-	int i;
-	u16 *unicode_name = var->VariableName;
-
-	for (i = 0; variable_validate[i].validate != NULL; i++) {
-		const char *name = variable_validate[i].name;
-		int match;
-
-		for (match = 0; ; match++) {
-			char c = name[match];
-			u16 u = unicode_name[match];
-
-			/* All special variables are plain ascii */
-			if (u > 127)
-				return true;
-
-			/* Wildcard in the matching name means we've matched */
-			if (c == '*')
-				return variable_validate[i].validate(var,
-							     match, data, len);
-
-			/* Case sensitive match */
-			if (c != u)
-				break;
-
-			/* Reached the end of the string while matching */
-			if (!c)
-				return variable_validate[i].validate(var,
-							     match, data, len);
-		}
-	}
-
-	return true;
-}
-
-static efi_status_t
-get_var_data_locked(struct efivars *efivars, struct efi_variable *var)
-{
-	efi_status_t status;
-
-	var->DataSize = 1024;
-	status = efivars->ops->get_variable(var->VariableName,
-					    &var->VendorGuid,
-					    &var->Attributes,
-					    &var->DataSize,
-					    var->Data);
-	return status;
-}
-
-static efi_status_t
-get_var_data(struct efivars *efivars, struct efi_variable *var)
-{
-	efi_status_t status;
-	unsigned long flags;
-
-	spin_lock_irqsave(&efivars->lock, flags);
-	status = get_var_data_locked(efivars, var);
-	spin_unlock_irqrestore(&efivars->lock, flags);
-
-	if (status != EFI_SUCCESS) {
-		printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n",
-			status);
-	}
-	return status;
-}
-
-static efi_status_t
-check_var_size_locked(struct efivars *efivars, u32 attributes,
-			unsigned long size)
-{
-	const struct efivar_operations *fops = efivars->ops;
-
-	if (!efivars->ops->query_variable_store)
-		return EFI_UNSUPPORTED;
-
-	return fops->query_variable_store(attributes, size);
-}
-
-
-static efi_status_t
-check_var_size(struct efivars *efivars, u32 attributes, unsigned long size)
-{
-	efi_status_t status;
-	unsigned long flags;
-
-	spin_lock_irqsave(&efivars->lock, flags);
-	status = check_var_size_locked(efivars, attributes, size);
-	spin_unlock_irqrestore(&efivars->lock, flags);
-
-	return status;
-}
-
-static ssize_t
-efivar_guid_read(struct efivar_entry *entry, char *buf)
-{
-	struct efi_variable *var = &entry->var;
-	char *str = buf;
-
-	if (!entry || !buf)
-		return 0;
-
-	efi_guid_unparse(&var->VendorGuid, str);
-	str += strlen(str);
-	str += sprintf(str, "\n");
-
-	return str - buf;
-}
-
-static ssize_t
-efivar_attr_read(struct efivar_entry *entry, char *buf)
-{
-	struct efi_variable *var = &entry->var;
-	char *str = buf;
-	efi_status_t status;
-
-	if (!entry || !buf)
-		return -EINVAL;
-
-	status = get_var_data(entry->efivars, var);
-	if (status != EFI_SUCCESS)
-		return -EIO;
-
-	if (var->Attributes & EFI_VARIABLE_NON_VOLATILE)
-		str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n");
-	if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS)
-		str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n");
-	if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS)
-		str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n");
-	if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
-		str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n");
-	if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS)
-		str += sprintf(str,
-			"EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n");
-	if (var->Attributes &
-			EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
-		str += sprintf(str,
-			"EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n");
-	if (var->Attributes & EFI_VARIABLE_APPEND_WRITE)
-		str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n");
-	return str - buf;
-}
-
-static ssize_t
-efivar_size_read(struct efivar_entry *entry, char *buf)
-{
-	struct efi_variable *var = &entry->var;
-	char *str = buf;
-	efi_status_t status;
-
-	if (!entry || !buf)
-		return -EINVAL;
-
-	status = get_var_data(entry->efivars, var);
-	if (status != EFI_SUCCESS)
-		return -EIO;
-
-	str += sprintf(str, "0x%lx\n", var->DataSize);
-	return str - buf;
-}
-
-static ssize_t
-efivar_data_read(struct efivar_entry *entry, char *buf)
-{
-	struct efi_variable *var = &entry->var;
-	efi_status_t status;
-
-	if (!entry || !buf)
-		return -EINVAL;
-
-	status = get_var_data(entry->efivars, var);
-	if (status != EFI_SUCCESS)
-		return -EIO;
-
-	memcpy(buf, var->Data, var->DataSize);
-	return var->DataSize;
-}
-/*
- * We allow each variable to be edited via rewriting the
- * entire efi variable structure.
- */
-static ssize_t
-efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
-{
-	struct efi_variable *new_var, *var = &entry->var;
-	struct efivars *efivars = entry->efivars;
-	efi_status_t status = EFI_NOT_FOUND;
-
-	if (count != sizeof(struct efi_variable))
-		return -EINVAL;
-
-	new_var = (struct efi_variable *)buf;
-	/*
-	 * If only updating the variable data, then the name
-	 * and guid should remain the same
-	 */
-	if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) ||
-		efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) {
-		printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n");
-		return -EINVAL;
-	}
-
-	if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){
-		printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n");
-		return -EINVAL;
-	}
-
-	if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 ||
-	    validate_var(new_var, new_var->Data, new_var->DataSize) == false) {
-		printk(KERN_ERR "efivars: Malformed variable content\n");
-		return -EINVAL;
-	}
-
-	spin_lock_irq(&efivars->lock);
-
-	status = check_var_size_locked(efivars, new_var->Attributes,
-	       new_var->DataSize + ucs2_strsize(new_var->VariableName, 1024));
-
-	if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED)
-		status = efivars->ops->set_variable(new_var->VariableName,
-						    &new_var->VendorGuid,
-						    new_var->Attributes,
-						    new_var->DataSize,
-						    new_var->Data);
-
-	spin_unlock_irq(&efivars->lock);
-
-	if (status != EFI_SUCCESS) {
-		printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
-			status);
-		return -EIO;
-	}
-
-	memcpy(&entry->var, new_var, count);
-	return count;
-}
-
-static ssize_t
-efivar_show_raw(struct efivar_entry *entry, char *buf)
-{
-	struct efi_variable *var = &entry->var;
-	efi_status_t status;
-
-	if (!entry || !buf)
-		return 0;
-
-	status = get_var_data(entry->efivars, var);
-	if (status != EFI_SUCCESS)
-		return -EIO;
-
-	memcpy(buf, var, sizeof(*var));
-	return sizeof(*var);
-}
-
-/*
- * Generic read/write functions that call the specific functions of
- * the attributes...
- */
-static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr,
-				char *buf)
-{
-	struct efivar_entry *var = to_efivar_entry(kobj);
-	struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
-	ssize_t ret = -EIO;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
-
-	if (efivar_attr->show) {
-		ret = efivar_attr->show(var, buf);
-	}
-	return ret;
-}
-
-static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr,
-				const char *buf, size_t count)
-{
-	struct efivar_entry *var = to_efivar_entry(kobj);
-	struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
-	ssize_t ret = -EIO;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
-
-	if (efivar_attr->store)
-		ret = efivar_attr->store(var, buf, count);
-
-	return ret;
-}
-
-static const struct sysfs_ops efivar_attr_ops = {
-	.show = efivar_attr_show,
-	.store = efivar_attr_store,
-};
-
-static void efivar_release(struct kobject *kobj)
-{
-	struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj);
-	kfree(var);
-}
-
-static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL);
-static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL);
-static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL);
-static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL);
-static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw);
-
-static struct attribute *def_attrs[] = {
-	&efivar_attr_guid.attr,
-	&efivar_attr_size.attr,
-	&efivar_attr_attributes.attr,
-	&efivar_attr_data.attr,
-	&efivar_attr_raw_var.attr,
-	NULL,
-};
-
-static struct kobj_type efivar_ktype = {
-	.release = efivar_release,
-	.sysfs_ops = &efivar_attr_ops,
-	.default_attrs = def_attrs,
-};
-
-static inline void
-efivar_unregister(struct efivar_entry *var)
-{
-	kobject_put(&var->kobj);
-}
-
-static int efivarfs_file_open(struct inode *inode, struct file *file)
-{
-	file->private_data = inode->i_private;
-	return 0;
-}
-
-static int efi_status_to_err(efi_status_t status)
-{
-	int err;
-
-	switch (status) {
-	case EFI_INVALID_PARAMETER:
-		err = -EINVAL;
-		break;
-	case EFI_OUT_OF_RESOURCES:
-		err = -ENOSPC;
-		break;
-	case EFI_DEVICE_ERROR:
-		err = -EIO;
-		break;
-	case EFI_WRITE_PROTECTED:
-		err = -EROFS;
-		break;
-	case EFI_SECURITY_VIOLATION:
-		err = -EACCES;
-		break;
-	case EFI_NOT_FOUND:
-		err = -EIO;
-		break;
-	default:
-		err = -EINVAL;
-	}
-
-	return err;
-}
-
-static ssize_t efivarfs_file_write(struct file *file,
-		const char __user *userbuf, size_t count, loff_t *ppos)
-{
-	struct efivar_entry *var = file->private_data;
-	struct efivars *efivars;
-	efi_status_t status;
-	void *data;
-	u32 attributes;
-	struct inode *inode = file->f_mapping->host;
-	unsigned long datasize = count - sizeof(attributes);
-	unsigned long newdatasize, varsize;
-	ssize_t bytes = 0;
-
-	if (count < sizeof(attributes))
-		return -EINVAL;
-
-	if (copy_from_user(&attributes, userbuf, sizeof(attributes)))
-		return -EFAULT;
-
-	if (attributes & ~(EFI_VARIABLE_MASK))
-		return -EINVAL;
-
-	efivars = var->efivars;
-
-	/*
-	 * Ensure that the user can't allocate arbitrarily large
-	 * amounts of memory. Pick a default size of 64K if
-	 * QueryVariableInfo() isn't supported by the firmware.
-	 */
-
-	varsize = datasize + ucs2_strsize(var->var.VariableName, 1024);
-	status = check_var_size(efivars, attributes, varsize);
-
-	if (status != EFI_SUCCESS) {
-		if (status != EFI_UNSUPPORTED)
-			return efi_status_to_err(status);
-
-		if (datasize > 65536)
-			return -ENOSPC;
-	}
-
-	data = kmalloc(datasize, GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	if (copy_from_user(data, userbuf + sizeof(attributes), datasize)) {
-		bytes = -EFAULT;
-		goto out;
-	}
-
-	if (validate_var(&var->var, data, datasize) == false) {
-		bytes = -EINVAL;
-		goto out;
-	}
-
-	/*
-	 * The lock here protects the get_variable call, the conditional
-	 * set_variable call, and removal of the variable from the efivars
-	 * list (in the case of an authenticated delete).
-	 */
-	spin_lock_irq(&efivars->lock);
-
-	/*
-	 * Ensure that the available space hasn't shrunk below the safe level
-	 */
-
-	status = check_var_size_locked(efivars, attributes, varsize);
-
-	if (status != EFI_SUCCESS && status != EFI_UNSUPPORTED) {
-		spin_unlock_irq(&efivars->lock);
-		kfree(data);
-
-		return efi_status_to_err(status);
-	}
-
-	status = efivars->ops->set_variable(var->var.VariableName,
-					    &var->var.VendorGuid,
-					    attributes, datasize,
-					    data);
-
-	if (status != EFI_SUCCESS) {
-		spin_unlock_irq(&efivars->lock);
-		kfree(data);
-
-		return efi_status_to_err(status);
-	}
-
-	bytes = count;
-
-	/*
-	 * Writing to the variable may have caused a change in size (which
-	 * could either be an append or an overwrite), or the variable to be
-	 * deleted. Perform a GetVariable() so we can tell what actually
-	 * happened.
-	 */
-	newdatasize = 0;
-	status = efivars->ops->get_variable(var->var.VariableName,
-					    &var->var.VendorGuid,
-					    NULL, &newdatasize,
-					    NULL);
-
-	if (status == EFI_BUFFER_TOO_SMALL) {
-		spin_unlock_irq(&efivars->lock);
-		mutex_lock(&inode->i_mutex);
-		i_size_write(inode, newdatasize + sizeof(attributes));
-		mutex_unlock(&inode->i_mutex);
-
-	} else if (status == EFI_NOT_FOUND) {
-		list_del(&var->list);
-		spin_unlock_irq(&efivars->lock);
-		efivar_unregister(var);
-		drop_nlink(inode);
-		d_delete(file->f_dentry);
-		dput(file->f_dentry);
-
-	} else {
-		spin_unlock_irq(&efivars->lock);
-		pr_warn("efivarfs: inconsistent EFI variable implementation? "
-				"status = %lx\n", status);
-	}
-
-out:
-	kfree(data);
-
-	return bytes;
-}
-
-static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf,
-		size_t count, loff_t *ppos)
-{
-	struct efivar_entry *var = file->private_data;
-	struct efivars *efivars = var->efivars;
-	efi_status_t status;
-	unsigned long datasize = 0;
-	u32 attributes;
-	void *data;
-	ssize_t size = 0;
-
-	spin_lock_irq(&efivars->lock);
-	status = efivars->ops->get_variable(var->var.VariableName,
-					    &var->var.VendorGuid,
-					    &attributes, &datasize, NULL);
-	spin_unlock_irq(&efivars->lock);
-
-	if (status != EFI_BUFFER_TOO_SMALL)
-		return efi_status_to_err(status);
-
-	data = kmalloc(datasize + sizeof(attributes), GFP_KERNEL);
-
-	if (!data)
-		return -ENOMEM;
-
-	spin_lock_irq(&efivars->lock);
-	status = efivars->ops->get_variable(var->var.VariableName,
-					    &var->var.VendorGuid,
-					    &attributes, &datasize,
-					    (data + sizeof(attributes)));
-	spin_unlock_irq(&efivars->lock);
-
-	if (status != EFI_SUCCESS) {
-		size = efi_status_to_err(status);
-		goto out_free;
-	}
-
-	memcpy(data, &attributes, sizeof(attributes));
-	size = simple_read_from_buffer(userbuf, count, ppos,
-				       data, datasize + sizeof(attributes));
-out_free:
-	kfree(data);
-
-	return size;
-}
-
-static void efivarfs_evict_inode(struct inode *inode)
-{
-	clear_inode(inode);
-}
-
-static const struct super_operations efivarfs_ops = {
-	.statfs = simple_statfs,
-	.drop_inode = generic_delete_inode,
-	.evict_inode = efivarfs_evict_inode,
-	.show_options = generic_show_options,
-};
-
-static struct super_block *efivarfs_sb;
-
-static const struct inode_operations efivarfs_dir_inode_operations;
-
-static const struct file_operations efivarfs_file_operations = {
-	.open	= efivarfs_file_open,
-	.read	= efivarfs_file_read,
-	.write	= efivarfs_file_write,
-	.llseek	= no_llseek,
-};
-
-static struct inode *efivarfs_get_inode(struct super_block *sb,
-				const struct inode *dir, int mode, dev_t dev)
-{
-	struct inode *inode = new_inode(sb);
-
-	if (inode) {
-		inode->i_ino = get_next_ino();
-		inode->i_mode = mode;
-		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-		switch (mode & S_IFMT) {
-		case S_IFREG:
-			inode->i_fop = &efivarfs_file_operations;
-			break;
-		case S_IFDIR:
-			inode->i_op = &efivarfs_dir_inode_operations;
-			inode->i_fop = &simple_dir_operations;
-			inc_nlink(inode);
-			break;
-		}
-	}
-	return inode;
-}
-
-/*
- * Return true if 'str' is a valid efivarfs filename of the form,
- *
- *	VariableName-12345678-1234-1234-1234-1234567891bc
- */
-static bool efivarfs_valid_name(const char *str, int len)
-{
-	static const char dashes[GUID_LEN] = {
-		[8] = 1, [13] = 1, [18] = 1, [23] = 1
-	};
-	const char *s = str + len - GUID_LEN;
-	int i;
-
-	/*
-	 * We need a GUID, plus at least one letter for the variable name,
-	 * plus the '-' separator
-	 */
-	if (len < GUID_LEN + 2)
-		return false;
-
-	/* GUID must be preceded by a '-' */
-	if (*(s - 1) != '-')
-		return false;
-
-	/*
-	 * Validate that 's' is of the correct format, e.g.
-	 *
-	 *	12345678-1234-1234-1234-123456789abc
-	 */
-	for (i = 0; i < GUID_LEN; i++) {
-		if (dashes[i]) {
-			if (*s++ != '-')
-				return false;
-		} else {
-			if (!isxdigit(*s++))
-				return false;
-		}
-	}
-
-	return true;
-}
-
-static void efivarfs_hex_to_guid(const char *str, efi_guid_t *guid)
-{
-	guid->b[0] = hex_to_bin(str[6]) << 4 | hex_to_bin(str[7]);
-	guid->b[1] = hex_to_bin(str[4]) << 4 | hex_to_bin(str[5]);
-	guid->b[2] = hex_to_bin(str[2]) << 4 | hex_to_bin(str[3]);
-	guid->b[3] = hex_to_bin(str[0]) << 4 | hex_to_bin(str[1]);
-	guid->b[4] = hex_to_bin(str[11]) << 4 | hex_to_bin(str[12]);
-	guid->b[5] = hex_to_bin(str[9]) << 4 | hex_to_bin(str[10]);
-	guid->b[6] = hex_to_bin(str[16]) << 4 | hex_to_bin(str[17]);
-	guid->b[7] = hex_to_bin(str[14]) << 4 | hex_to_bin(str[15]);
-	guid->b[8] = hex_to_bin(str[19]) << 4 | hex_to_bin(str[20]);
-	guid->b[9] = hex_to_bin(str[21]) << 4 | hex_to_bin(str[22]);
-	guid->b[10] = hex_to_bin(str[24]) << 4 | hex_to_bin(str[25]);
-	guid->b[11] = hex_to_bin(str[26]) << 4 | hex_to_bin(str[27]);
-	guid->b[12] = hex_to_bin(str[28]) << 4 | hex_to_bin(str[29]);
-	guid->b[13] = hex_to_bin(str[30]) << 4 | hex_to_bin(str[31]);
-	guid->b[14] = hex_to_bin(str[32]) << 4 | hex_to_bin(str[33]);
-	guid->b[15] = hex_to_bin(str[34]) << 4 | hex_to_bin(str[35]);
-}
-
-static int efivarfs_create(struct inode *dir, struct dentry *dentry,
-			  umode_t mode, bool excl)
-{
-	struct inode *inode;
-	struct efivars *efivars = &__efivars;
-	struct efivar_entry *var;
-	int namelen, i = 0, err = 0;
-
-	if (!efivarfs_valid_name(dentry->d_name.name, dentry->d_name.len))
-		return -EINVAL;
-
-	inode = efivarfs_get_inode(dir->i_sb, dir, mode, 0);
-	if (!inode)
-		return -ENOMEM;
-
-	var = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL);
-	if (!var) {
-		err = -ENOMEM;
-		goto out;
-	}
-
-	/* length of the variable name itself: remove GUID and separator */
-	namelen = dentry->d_name.len - GUID_LEN - 1;
-
-	efivarfs_hex_to_guid(dentry->d_name.name + namelen + 1,
-			&var->var.VendorGuid);
-
-	for (i = 0; i < namelen; i++)
-		var->var.VariableName[i] = dentry->d_name.name[i];
-
-	var->var.VariableName[i] = '\0';
-
-	inode->i_private = var;
-	var->efivars = efivars;
-	var->kobj.kset = efivars->kset;
-
-	err = kobject_init_and_add(&var->kobj, &efivar_ktype, NULL, "%s",
-			     dentry->d_name.name);
-	if (err)
-		goto out;
-
-	kobject_uevent(&var->kobj, KOBJ_ADD);
-	spin_lock_irq(&efivars->lock);
-	list_add(&var->list, &efivars->list);
-	spin_unlock_irq(&efivars->lock);
-	d_instantiate(dentry, inode);
-	dget(dentry);
-out:
-	if (err) {
-		kfree(var);
-		iput(inode);
-	}
-	return err;
-}
-
-static int efivarfs_unlink(struct inode *dir, struct dentry *dentry)
-{
-	struct efivar_entry *var = dentry->d_inode->i_private;
-	struct efivars *efivars = var->efivars;
-	efi_status_t status;
-
-	spin_lock_irq(&efivars->lock);
-
-	status = efivars->ops->set_variable(var->var.VariableName,
-					    &var->var.VendorGuid,
-					    0, 0, NULL);
-
-	if (status == EFI_SUCCESS || status == EFI_NOT_FOUND) {
-		list_del(&var->list);
-		spin_unlock_irq(&efivars->lock);
-		efivar_unregister(var);
-		drop_nlink(dentry->d_inode);
-		dput(dentry);
-		return 0;
-	}
-
-	spin_unlock_irq(&efivars->lock);
-	return -EINVAL;
-};
-
-/*
- * Compare two efivarfs file names.
- *
- * An efivarfs filename is composed of two parts,
- *
- *	1. A case-sensitive variable name
- *	2. A case-insensitive GUID
- *
- * So we need to perform a case-sensitive match on part 1 and a
- * case-insensitive match on part 2.
- */
-static int efivarfs_d_compare(const struct dentry *parent, const struct inode *pinode,
-			      const struct dentry *dentry, const struct inode *inode,
-			      unsigned int len, const char *str,
-			      const struct qstr *name)
-{
-	int guid = len - GUID_LEN;
-
-	if (name->len != len)
-		return 1;
-
-	/* Case-sensitive compare for the variable name */
-	if (memcmp(str, name->name, guid))
-		return 1;
-
-	/* Case-insensitive compare for the GUID */
-	return strncasecmp(name->name + guid, str + guid, GUID_LEN);
-}
-
-static int efivarfs_d_hash(const struct dentry *dentry,
-			   const struct inode *inode, struct qstr *qstr)
-{
-	unsigned long hash = init_name_hash();
-	const unsigned char *s = qstr->name;
-	unsigned int len = qstr->len;
-
-	if (!efivarfs_valid_name(s, len))
-		return -EINVAL;
-
-	while (len-- > GUID_LEN)
-		hash = partial_name_hash(*s++, hash);
-
-	/* GUID is case-insensitive. */
-	while (len--)
-		hash = partial_name_hash(tolower(*s++), hash);
-
-	qstr->hash = end_name_hash(hash);
-	return 0;
-}
-
-/*
- * Retaining negative dentries for an in-memory filesystem just wastes
- * memory and lookup time: arrange for them to be deleted immediately.
- */
-static int efivarfs_delete_dentry(const struct dentry *dentry)
-{
-	return 1;
-}
-
-static struct dentry_operations efivarfs_d_ops = {
-	.d_compare = efivarfs_d_compare,
-	.d_hash = efivarfs_d_hash,
-	.d_delete = efivarfs_delete_dentry,
-};
-
-static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name)
-{
-	struct dentry *d;
-	struct qstr q;
-	int err;
-
-	q.name = name;
-	q.len = strlen(name);
-
-	err = efivarfs_d_hash(NULL, NULL, &q);
-	if (err)
-		return ERR_PTR(err);
-
-	d = d_alloc(parent, &q);
-	if (d)
-		return d;
-
-	return ERR_PTR(-ENOMEM);
-}
-
-static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
-{
-	struct inode *inode = NULL;
-	struct dentry *root;
-	struct efivar_entry *entry, *n;
-	struct efivars *efivars = &__efivars;
-	char *name;
-	int err = -ENOMEM;
-
-	efivarfs_sb = sb;
-
-	sb->s_maxbytes          = MAX_LFS_FILESIZE;
-	sb->s_blocksize         = PAGE_CACHE_SIZE;
-	sb->s_blocksize_bits    = PAGE_CACHE_SHIFT;
-	sb->s_magic             = EFIVARFS_MAGIC;
-	sb->s_op                = &efivarfs_ops;
-	sb->s_d_op		= &efivarfs_d_ops;
-	sb->s_time_gran         = 1;
-
-	inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0);
-	if (!inode)
-		return -ENOMEM;
-	inode->i_op = &efivarfs_dir_inode_operations;
-
-	root = d_make_root(inode);
-	sb->s_root = root;
-	if (!root)
-		return -ENOMEM;
-
-	list_for_each_entry_safe(entry, n, &efivars->list, list) {
-		struct dentry *dentry, *root = efivarfs_sb->s_root;
-		unsigned long size = 0;
-		int len, i;
-
-		inode = NULL;
-
-		len = ucs2_strlen(entry->var.VariableName);
-
-		/* name, plus '-', plus GUID, plus NUL*/
-		name = kmalloc(len + 1 + GUID_LEN + 1, GFP_ATOMIC);
-		if (!name)
-			goto fail;
-
-		for (i = 0; i < len; i++)
-			name[i] = entry->var.VariableName[i] & 0xFF;
-
-		name[len] = '-';
-
-		efi_guid_unparse(&entry->var.VendorGuid, name + len + 1);
-
-		name[len+GUID_LEN+1] = '\0';
-
-		inode = efivarfs_get_inode(efivarfs_sb, root->d_inode,
-					  S_IFREG | 0644, 0);
-		if (!inode)
-			goto fail_name;
-
-		dentry = efivarfs_alloc_dentry(root, name);
-		if (IS_ERR(dentry)) {
-			err = PTR_ERR(dentry);
-			goto fail_inode;
-		}
-
-		/* copied by the above to local storage in the dentry. */
-		kfree(name);
-
-		spin_lock_irq(&efivars->lock);
-		efivars->ops->get_variable(entry->var.VariableName,
-					   &entry->var.VendorGuid,
-					   &entry->var.Attributes,
-					   &size,
-					   NULL);
-		spin_unlock_irq(&efivars->lock);
-
-		mutex_lock(&inode->i_mutex);
-		inode->i_private = entry;
-		i_size_write(inode, size + sizeof(entry->var.Attributes));
-		mutex_unlock(&inode->i_mutex);
-		d_add(dentry, inode);
-	}
-
-	return 0;
-
-fail_inode:
-	iput(inode);
-fail_name:
-	kfree(name);
-fail:
-	return err;
-}
-
-static struct dentry *efivarfs_mount(struct file_system_type *fs_type,
-				    int flags, const char *dev_name, void *data)
-{
-	return mount_single(fs_type, flags, data, efivarfs_fill_super);
-}
-
-static void efivarfs_kill_sb(struct super_block *sb)
-{
-	kill_litter_super(sb);
-	efivarfs_sb = NULL;
-}
-
-static struct file_system_type efivarfs_type = {
-	.name    = "efivarfs",
-	.mount   = efivarfs_mount,
-	.kill_sb = efivarfs_kill_sb,
-};
-MODULE_ALIAS_FS("efivarfs");
-
-/*
- * Handle negative dentry.
- */
-static struct dentry *efivarfs_lookup(struct inode *dir, struct dentry *dentry,
-				      unsigned int flags)
-{
-	if (dentry->d_name.len > NAME_MAX)
-		return ERR_PTR(-ENAMETOOLONG);
-	d_add(dentry, NULL);
-	return NULL;
-}
-
-static const struct inode_operations efivarfs_dir_inode_operations = {
-	.lookup = efivarfs_lookup,
-	.unlink = efivarfs_unlink,
-	.create = efivarfs_create,
-};
-
-#ifdef CONFIG_EFI_VARS_PSTORE
-
-static int efi_pstore_open(struct pstore_info *psi)
-{
-	struct efivars *efivars = psi->data;
-
-	spin_lock_irq(&efivars->lock);
-	efivars->walk_entry = list_first_entry(&efivars->list,
-					       struct efivar_entry, list);
-	return 0;
-}
-
-static int efi_pstore_close(struct pstore_info *psi)
-{
-	struct efivars *efivars = psi->data;
-
-	spin_unlock_irq(&efivars->lock);
-	return 0;
-}
-
-static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
-			       int *count, struct timespec *timespec,
-			       char **buf, struct pstore_info *psi)
-{
-	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
-	struct efivars *efivars = psi->data;
-	char name[DUMP_NAME_LEN];
-	int i;
-	int cnt;
-	unsigned int part, size;
-	unsigned long time;
-
-	while (&efivars->walk_entry->list != &efivars->list) {
-		if (!efi_guidcmp(efivars->walk_entry->var.VendorGuid,
-				 vendor)) {
-			for (i = 0; i < DUMP_NAME_LEN; i++) {
-				name[i] = efivars->walk_entry->var.VariableName[i];
-			}
-			if (sscanf(name, "dump-type%u-%u-%d-%lu",
-				   type, &part, &cnt, &time) == 4) {
-				*id = part;
-				*count = cnt;
-				timespec->tv_sec = time;
-				timespec->tv_nsec = 0;
-			} else if (sscanf(name, "dump-type%u-%u-%lu",
-				   type, &part, &time) == 3) {
-				/*
-				 * Check if an old format,
-				 * which doesn't support holding
-				 * multiple logs, remains.
-				 */
-				*id = part;
-				*count = 0;
-				timespec->tv_sec = time;
-				timespec->tv_nsec = 0;
-			} else {
-				efivars->walk_entry = list_entry(
-						efivars->walk_entry->list.next,
-						struct efivar_entry, list);
-				continue;
-			}
-
-			get_var_data_locked(efivars, &efivars->walk_entry->var);
-			size = efivars->walk_entry->var.DataSize;
-			*buf = kmalloc(size, GFP_KERNEL);
-			if (*buf == NULL)
-				return -ENOMEM;
-			memcpy(*buf, efivars->walk_entry->var.Data,
-			       size);
-			efivars->walk_entry = list_entry(
-					efivars->walk_entry->list.next,
-					struct efivar_entry, list);
-			return size;
-		}
-		efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
-						 struct efivar_entry, list);
-	}
-	return 0;
-}
-
-static int efi_pstore_write(enum pstore_type_id type,
-		enum kmsg_dump_reason reason, u64 *id,
-		unsigned int part, int count, size_t size,
-		struct pstore_info *psi)
-{
-	char name[DUMP_NAME_LEN];
-	efi_char16_t efi_name[DUMP_NAME_LEN];
-	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
-	struct efivars *efivars = psi->data;
-	int i, ret = 0;
-	efi_status_t status = EFI_NOT_FOUND;
-	unsigned long flags;
-
-	if (pstore_cannot_block_path(reason)) {
-		/*
-		 * If the lock is taken by another cpu in non-blocking path,
-		 * this driver returns without entering firmware to avoid
-		 * hanging up.
-		 */
-		if (!spin_trylock_irqsave(&efivars->lock, flags))
-			return -EBUSY;
-	} else
-		spin_lock_irqsave(&efivars->lock, flags);
-
-	/*
-	 * Check if there is a space enough to log.
-	 * size: a size of logging data
-	 * DUMP_NAME_LEN * 2: a maximum size of variable name
-	 */
-
-	status = check_var_size_locked(efivars, PSTORE_EFI_ATTRIBUTES,
-					 size + DUMP_NAME_LEN * 2);
-
-	if (status) {
-		spin_unlock_irqrestore(&efivars->lock, flags);
-		*id = part;
-		return -ENOSPC;
-	}
-
-	sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count,
-		get_seconds());
-
-	for (i = 0; i < DUMP_NAME_LEN; i++)
-		efi_name[i] = name[i];
-
-	efivars->ops->set_variable(efi_name, &vendor, PSTORE_EFI_ATTRIBUTES,
-				   size, psi->buf);
-
-	spin_unlock_irqrestore(&efivars->lock, flags);
-
-	if (reason == KMSG_DUMP_OOPS && efivar_wq_enabled)
-		schedule_work(&efivar_work);
-
-	*id = part;
-	return ret;
-};
-
-static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
-			    struct timespec time, struct pstore_info *psi)
-{
-	char name[DUMP_NAME_LEN];
-	efi_char16_t efi_name[DUMP_NAME_LEN];
-	char name_old[DUMP_NAME_LEN];
-	efi_char16_t efi_name_old[DUMP_NAME_LEN];
-	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
-	struct efivars *efivars = psi->data;
-	struct efivar_entry *entry, *found = NULL;
-	int i;
-
-	sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count,
-		time.tv_sec);
-
-	spin_lock_irq(&efivars->lock);
-
-	for (i = 0; i < DUMP_NAME_LEN; i++)
-		efi_name[i] = name[i];
-
-	/*
-	 * Clean up an entry with the same name
-	 */
-
-	list_for_each_entry(entry, &efivars->list, list) {
-		get_var_data_locked(efivars, &entry->var);
-
-		if (efi_guidcmp(entry->var.VendorGuid, vendor))
-			continue;
-		if (ucs2_strncmp(entry->var.VariableName, efi_name,
-				  ucs2_strlen(efi_name))) {
-			/*
-			 * Check if an old format,
-			 * which doesn't support holding
-			 * multiple logs, remains.
-			 */
-			sprintf(name_old, "dump-type%u-%u-%lu", type,
-				(unsigned int)id, time.tv_sec);
-
-			for (i = 0; i < DUMP_NAME_LEN; i++)
-				efi_name_old[i] = name_old[i];
-
-			if (ucs2_strncmp(entry->var.VariableName, efi_name_old,
-					  ucs2_strlen(efi_name_old)))
-				continue;
-		}
-
-		/* found */
-		found = entry;
-		efivars->ops->set_variable(entry->var.VariableName,
-					   &entry->var.VendorGuid,
-					   PSTORE_EFI_ATTRIBUTES,
-					   0, NULL);
-		break;
-	}
-
-	if (found)
-		list_del(&found->list);
-
-	spin_unlock_irq(&efivars->lock);
-
-	if (found)
-		efivar_unregister(found);
-
-	return 0;
-}
-
-static struct pstore_info efi_pstore_info = {
-	.owner		= THIS_MODULE,
-	.name		= "efi",
-	.open		= efi_pstore_open,
-	.close		= efi_pstore_close,
-	.read		= efi_pstore_read,
-	.write		= efi_pstore_write,
-	.erase		= efi_pstore_erase,
-};
-
-static void efivar_pstore_register(struct efivars *efivars)
-{
-	efivars->efi_pstore_info = efi_pstore_info;
-	efivars->efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL);
-	if (efivars->efi_pstore_info.buf) {
-		efivars->efi_pstore_info.bufsize = 1024;
-		efivars->efi_pstore_info.data = efivars;
-		spin_lock_init(&efivars->efi_pstore_info.buf_lock);
-		pstore_register(&efivars->efi_pstore_info);
-	}
-}
-#else
-static void efivar_pstore_register(struct efivars *efivars)
-{
-	return;
-}
-#endif
-
-static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
-			     struct bin_attribute *bin_attr,
-			     char *buf, loff_t pos, size_t count)
-{
-	struct efi_variable *new_var = (struct efi_variable *)buf;
-	struct efivars *efivars = bin_attr->private;
-	struct efivar_entry *search_efivar, *n;
-	unsigned long strsize1, strsize2;
-	efi_status_t status = EFI_NOT_FOUND;
-	int found = 0;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
-
-	if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 ||
-	    validate_var(new_var, new_var->Data, new_var->DataSize) == false) {
-		printk(KERN_ERR "efivars: Malformed variable content\n");
-		return -EINVAL;
-	}
-
-	spin_lock_irq(&efivars->lock);
-
-	/*
-	 * Does this variable already exist?
-	 */
-	list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
-		strsize1 = ucs2_strsize(search_efivar->var.VariableName, 1024);
-		strsize2 = ucs2_strsize(new_var->VariableName, 1024);
-		if (strsize1 == strsize2 &&
-			!memcmp(&(search_efivar->var.VariableName),
-				new_var->VariableName, strsize1) &&
-			!efi_guidcmp(search_efivar->var.VendorGuid,
-				new_var->VendorGuid)) {
-			found = 1;
-			break;
-		}
-	}
-	if (found) {
-		spin_unlock_irq(&efivars->lock);
-		return -EINVAL;
-	}
-
-	status = check_var_size_locked(efivars, new_var->Attributes,
-	       new_var->DataSize + ucs2_strsize(new_var->VariableName, 1024));
-
-	if (status && status != EFI_UNSUPPORTED) {
-		spin_unlock_irq(&efivars->lock);
-		return efi_status_to_err(status);
-	}
-
-	/* now *really* create the variable via EFI */
-	status = efivars->ops->set_variable(new_var->VariableName,
-					    &new_var->VendorGuid,
-					    new_var->Attributes,
-					    new_var->DataSize,
-					    new_var->Data);
-
-	if (status != EFI_SUCCESS) {
-		printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
-			status);
-		spin_unlock_irq(&efivars->lock);
-		return -EIO;
-	}
-	spin_unlock_irq(&efivars->lock);
-
-	/* Create the entry in sysfs.  Locking is not required here */
-	status = efivar_create_sysfs_entry(efivars,
-					   ucs2_strsize(new_var->VariableName,
-							 1024),
-					   new_var->VariableName,
-					   &new_var->VendorGuid);
-	if (status) {
-		printk(KERN_WARNING "efivars: variable created, but sysfs entry wasn't.\n");
-	}
-	return count;
-}
-
-static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
-			     struct bin_attribute *bin_attr,
-			     char *buf, loff_t pos, size_t count)
-{
-	struct efi_variable *del_var = (struct efi_variable *)buf;
-	struct efivars *efivars = bin_attr->private;
-	struct efivar_entry *search_efivar, *n;
-	unsigned long strsize1, strsize2;
-	efi_status_t status = EFI_NOT_FOUND;
-	int found = 0;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
-
-	spin_lock_irq(&efivars->lock);
-
-	/*
-	 * Does this variable already exist?
-	 */
-	list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
-		strsize1 = ucs2_strsize(search_efivar->var.VariableName, 1024);
-		strsize2 = ucs2_strsize(del_var->VariableName, 1024);
-		if (strsize1 == strsize2 &&
-			!memcmp(&(search_efivar->var.VariableName),
-				del_var->VariableName, strsize1) &&
-			!efi_guidcmp(search_efivar->var.VendorGuid,
-				del_var->VendorGuid)) {
-			found = 1;
-			break;
-		}
-	}
-	if (!found) {
-		spin_unlock_irq(&efivars->lock);
-		return -EINVAL;
-	}
-	/* force the Attributes/DataSize to 0 to ensure deletion */
-	del_var->Attributes = 0;
-	del_var->DataSize = 0;
-
-	status = efivars->ops->set_variable(del_var->VariableName,
-					    &del_var->VendorGuid,
-					    del_var->Attributes,
-					    del_var->DataSize,
-					    del_var->Data);
-
-	if (status != EFI_SUCCESS) {
-		printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
-			status);
-		spin_unlock_irq(&efivars->lock);
-		return -EIO;
-	}
-	list_del(&search_efivar->list);
-	/* We need to release this lock before unregistering. */
-	spin_unlock_irq(&efivars->lock);
-	efivar_unregister(search_efivar);
-
-	/* It's dead Jim.... */
-	return count;
-}
-
-static bool variable_is_present(struct efivars *efivars,
-				efi_char16_t *variable_name,
-				efi_guid_t *vendor)
-{
-	struct efivar_entry *entry, *n;
-	unsigned long strsize1, strsize2;
-	bool found = false;
-
-	strsize1 = ucs2_strsize(variable_name, 1024);
-	list_for_each_entry_safe(entry, n, &efivars->list, list) {
-		strsize2 = ucs2_strsize(entry->var.VariableName, 1024);
-		if (strsize1 == strsize2 &&
-			!memcmp(variable_name, &(entry->var.VariableName),
-				strsize2) &&
-			!efi_guidcmp(entry->var.VendorGuid,
-				*vendor)) {
-			found = true;
-			break;
-		}
-	}
-	return found;
-}
-
-/*
- * Returns the size of variable_name, in bytes, including the
- * terminating NULL character, or variable_name_size if no NULL
- * character is found among the first variable_name_size bytes.
- */
-static unsigned long var_name_strnsize(efi_char16_t *variable_name,
-				       unsigned long variable_name_size)
-{
-	unsigned long len;
-	efi_char16_t c;
-
-	/*
-	 * The variable name is, by definition, a NULL-terminated
-	 * string, so make absolutely sure that variable_name_size is
-	 * the value we expect it to be. If not, return the real size.
-	 */
-	for (len = 2; len <= variable_name_size; len += sizeof(c)) {
-		c = variable_name[(len / sizeof(c)) - 1];
-		if (!c)
-			break;
-	}
-
-	return min(len, variable_name_size);
-}
-
-static void efivar_update_sysfs_entries(struct work_struct *work)
-{
-	struct efivars *efivars = &__efivars;
-	efi_guid_t vendor;
-	efi_char16_t *variable_name;
-	unsigned long variable_name_size = 1024;
-	efi_status_t status = EFI_NOT_FOUND;
-	bool found;
-
-	/* Add new sysfs entries */
-	while (1) {
-		variable_name = kzalloc(variable_name_size, GFP_KERNEL);
-		if (!variable_name) {
-			pr_err("efivars: Memory allocation failed.\n");
-			return;
-		}
-
-		spin_lock_irq(&efivars->lock);
-		found = false;
-		while (1) {
-			variable_name_size = 1024;
-			status = efivars->ops->get_next_variable(
-							&variable_name_size,
-							variable_name,
-							&vendor);
-			if (status != EFI_SUCCESS) {
-				break;
-			} else {
-				if (!variable_is_present(efivars,
-				    variable_name, &vendor)) {
-					found = true;
-					break;
-				}
-			}
-		}
-		spin_unlock_irq(&efivars->lock);
-
-		if (!found) {
-			kfree(variable_name);
-			break;
-		} else {
-			variable_name_size = var_name_strnsize(variable_name,
-							       variable_name_size);
-			efivar_create_sysfs_entry(efivars,
-						  variable_name_size,
-						  variable_name, &vendor);
-		}
-	}
-}
-
-/*
- * Let's not leave out systab information that snuck into
- * the efivars driver
- */
-static ssize_t systab_show(struct kobject *kobj,
-			   struct kobj_attribute *attr, char *buf)
-{
-	char *str = buf;
-
-	if (!kobj || !buf)
-		return -EINVAL;
-
-	if (efi.mps != EFI_INVALID_TABLE_ADDR)
-		str += sprintf(str, "MPS=0x%lx\n", efi.mps);
-	if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
-		str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
-	if (efi.acpi != EFI_INVALID_TABLE_ADDR)
-		str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
-	if (efi.smbios != EFI_INVALID_TABLE_ADDR)
-		str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
-	if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
-		str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
-	if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
-		str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
-	if (efi.uga != EFI_INVALID_TABLE_ADDR)
-		str += sprintf(str, "UGA=0x%lx\n", efi.uga);
-
-	return str - buf;
-}
-
-static struct kobj_attribute efi_attr_systab =
-			__ATTR(systab, 0400, systab_show, NULL);
-
-static struct attribute *efi_subsys_attrs[] = {
-	&efi_attr_systab.attr,
-	NULL,	/* maybe more in the future? */
-};
-
-static struct attribute_group efi_subsys_attr_group = {
-	.attrs = efi_subsys_attrs,
-};
-
-static struct kobject *efi_kobj;
-
-/*
- * efivar_create_sysfs_entry()
- * Requires:
- *    variable_name_size = number of bytes required to hold
- *                         variable_name (not counting the NULL
- *                         character at the end.
- *    efivars->lock is not held on entry or exit.
- * Returns 1 on failure, 0 on success
- */
-static int
-efivar_create_sysfs_entry(struct efivars *efivars,
-			  unsigned long variable_name_size,
-			  efi_char16_t *variable_name,
-			  efi_guid_t *vendor_guid)
-{
-	int i, short_name_size;
-	char *short_name;
-	struct efivar_entry *new_efivar;
-
-	/*
-	 * Length of the variable bytes in ASCII, plus the '-' separator,
-	 * plus the GUID, plus trailing NUL
-	 */
-	short_name_size = variable_name_size / sizeof(efi_char16_t)
-				+ 1 + GUID_LEN + 1;
-
-	short_name = kzalloc(short_name_size, GFP_KERNEL);
-	new_efivar = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL);
-
-	if (!short_name || !new_efivar)  {
-		kfree(short_name);
-		kfree(new_efivar);
-		return 1;
-	}
-
-	new_efivar->efivars = efivars;
-	memcpy(new_efivar->var.VariableName, variable_name,
-		variable_name_size);
-	memcpy(&(new_efivar->var.VendorGuid), vendor_guid, sizeof(efi_guid_t));
-
-	/* Convert Unicode to normal chars (assume top bits are 0),
-	   ala UTF-8 */
-	for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) {
-		short_name[i] = variable_name[i] & 0xFF;
-	}
-	/* This is ugly, but necessary to separate one vendor's
-	   private variables from another's.         */
-
-	*(short_name + strlen(short_name)) = '-';
-	efi_guid_unparse(vendor_guid, short_name + strlen(short_name));
-
-	new_efivar->kobj.kset = efivars->kset;
-	i = kobject_init_and_add(&new_efivar->kobj, &efivar_ktype, NULL,
-				 "%s", short_name);
-	if (i) {
-		kfree(short_name);
-		kfree(new_efivar);
-		return 1;
-	}
-
-	kobject_uevent(&new_efivar->kobj, KOBJ_ADD);
-	kfree(short_name);
-	short_name = NULL;
-
-	spin_lock_irq(&efivars->lock);
-	list_add(&new_efivar->list, &efivars->list);
-	spin_unlock_irq(&efivars->lock);
-
-	return 0;
-}
-
-static int
-create_efivars_bin_attributes(struct efivars *efivars)
-{
-	struct bin_attribute *attr;
-	int error;
-
-	/* new_var */
-	attr = kzalloc(sizeof(*attr), GFP_KERNEL);
-	if (!attr)
-		return -ENOMEM;
-
-	attr->attr.name = "new_var";
-	attr->attr.mode = 0200;
-	attr->write = efivar_create;
-	attr->private = efivars;
-	efivars->new_var = attr;
-
-	/* del_var */
-	attr = kzalloc(sizeof(*attr), GFP_KERNEL);
-	if (!attr) {
-		error = -ENOMEM;
-		goto out_free;
-	}
-	attr->attr.name = "del_var";
-	attr->attr.mode = 0200;
-	attr->write = efivar_delete;
-	attr->private = efivars;
-	efivars->del_var = attr;
-
-	sysfs_bin_attr_init(efivars->new_var);
-	sysfs_bin_attr_init(efivars->del_var);
-
-	/* Register */
-	error = sysfs_create_bin_file(&efivars->kset->kobj,
-				      efivars->new_var);
-	if (error) {
-		printk(KERN_ERR "efivars: unable to create new_var sysfs file"
-			" due to error %d\n", error);
-		goto out_free;
-	}
-	error = sysfs_create_bin_file(&efivars->kset->kobj,
-				      efivars->del_var);
-	if (error) {
-		printk(KERN_ERR "efivars: unable to create del_var sysfs file"
-			" due to error %d\n", error);
-		sysfs_remove_bin_file(&efivars->kset->kobj,
-				      efivars->new_var);
-		goto out_free;
-	}
-
-	return 0;
-out_free:
-	kfree(efivars->del_var);
-	efivars->del_var = NULL;
-	kfree(efivars->new_var);
-	efivars->new_var = NULL;
-	return error;
-}
-
-void unregister_efivars(struct efivars *efivars)
-{
-	struct efivar_entry *entry, *n;
-
-	list_for_each_entry_safe(entry, n, &efivars->list, list) {
-		spin_lock_irq(&efivars->lock);
-		list_del(&entry->list);
-		spin_unlock_irq(&efivars->lock);
-		efivar_unregister(entry);
-	}
-	if (efivars->new_var)
-		sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var);
-	if (efivars->del_var)
-		sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var);
-	kfree(efivars->new_var);
-	kfree(efivars->del_var);
-	kobject_put(efivars->kobject);
-	kset_unregister(efivars->kset);
-}
-EXPORT_SYMBOL_GPL(unregister_efivars);
-
-/*
- * Print a warning when duplicate EFI variables are encountered and
- * disable the sysfs workqueue since the firmware is buggy.
- */
-static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid,
-			     unsigned long len16)
-{
-	size_t i, len8 = len16 / sizeof(efi_char16_t);
-	char *s8;
-
-	/*
-	 * Disable the workqueue since the algorithm it uses for
-	 * detecting new variables won't work with this buggy
-	 * implementation of GetNextVariableName().
-	 */
-	efivar_wq_enabled = false;
-
-	s8 = kzalloc(len8, GFP_KERNEL);
-	if (!s8)
-		return;
-
-	for (i = 0; i < len8; i++)
-		s8[i] = s16[i];
-
-	printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n",
-	       s8, vendor_guid);
-	kfree(s8);
-}
-
-int register_efivars(struct efivars *efivars,
-		     const struct efivar_operations *ops,
-		     struct kobject *parent_kobj)
-{
-	efi_status_t status = EFI_NOT_FOUND;
-	efi_guid_t vendor_guid;
-	efi_char16_t *variable_name;
-	unsigned long variable_name_size = 1024;
-	int error = 0;
-
-	variable_name = kzalloc(variable_name_size, GFP_KERNEL);
-	if (!variable_name) {
-		printk(KERN_ERR "efivars: Memory allocation failed.\n");
-		return -ENOMEM;
-	}
-
-	spin_lock_init(&efivars->lock);
-	INIT_LIST_HEAD(&efivars->list);
-	efivars->ops = ops;
-
-	efivars->kset = kset_create_and_add("vars", NULL, parent_kobj);
-	if (!efivars->kset) {
-		printk(KERN_ERR "efivars: Subsystem registration failed.\n");
-		error = -ENOMEM;
-		goto out;
-	}
-
-	efivars->kobject = kobject_create_and_add("efivars", parent_kobj);
-	if (!efivars->kobject) {
-		pr_err("efivars: Subsystem registration failed.\n");
-		error = -ENOMEM;
-		kset_unregister(efivars->kset);
-		goto out;
-	}
-
-	/*
-	 * Per EFI spec, the maximum storage allocated for both
-	 * the variable name and variable data is 1024 bytes.
-	 */
-
-	do {
-		variable_name_size = 1024;
-
-		status = ops->get_next_variable(&variable_name_size,
-						variable_name,
-						&vendor_guid);
-		switch (status) {
-		case EFI_SUCCESS:
-			variable_name_size = var_name_strnsize(variable_name,
-							       variable_name_size);
-
-			/*
-			 * Some firmware implementations return the
-			 * same variable name on multiple calls to
-			 * get_next_variable(). Terminate the loop
-			 * immediately as there is no guarantee that
-			 * we'll ever see a different variable name,
-			 * and may end up looping here forever.
-			 */
-			if (variable_is_present(efivars, variable_name,
-						&vendor_guid)) {
-				dup_variable_bug(variable_name, &vendor_guid,
-						 variable_name_size);
-				status = EFI_NOT_FOUND;
-				break;
-			}
-
-			efivar_create_sysfs_entry(efivars,
-						  variable_name_size,
-						  variable_name,
-						  &vendor_guid);
-			break;
-		case EFI_NOT_FOUND:
-			break;
-		default:
-			printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n",
-				status);
-			status = EFI_NOT_FOUND;
-			break;
-		}
-	} while (status != EFI_NOT_FOUND);
-
-	error = create_efivars_bin_attributes(efivars);
-	if (error)
-		unregister_efivars(efivars);
-
-	if (!efivars_pstore_disable)
-		efivar_pstore_register(efivars);
-
-	register_filesystem(&efivarfs_type);
-
-out:
-	kfree(variable_name);
-
-	return error;
-}
-EXPORT_SYMBOL_GPL(register_efivars);
-
-/*
- * For now we register the efi subsystem with the firmware subsystem
- * and the vars subsystem with the efi subsystem.  In the future, it
- * might make sense to split off the efi subsystem into its own
- * driver, but for now only efivars will register with it, so just
- * include it here.
- */
-
-static int __init
-efivars_init(void)
-{
-	int error = 0;
-
-	printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION,
-	       EFIVARS_DATE);
-
-	if (!efi_enabled(EFI_RUNTIME_SERVICES))
-		return 0;
-
-	/* For now we'll register the efi directory at /sys/firmware/efi */
-	efi_kobj = kobject_create_and_add("efi", firmware_kobj);
-	if (!efi_kobj) {
-		printk(KERN_ERR "efivars: Firmware registration failed.\n");
-		return -ENOMEM;
-	}
-
-	ops.get_variable = efi.get_variable;
-	ops.set_variable = efi.set_variable;
-	ops.get_next_variable = efi.get_next_variable;
-	ops.query_variable_store = efi_query_variable_store;
-
-	error = register_efivars(&__efivars, &ops, efi_kobj);
-	if (error)
-		goto err_put;
-
-	/* Don't forget the systab entry */
-	error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
-	if (error) {
-		printk(KERN_ERR
-		       "efivars: Sysfs attribute export failed with error %d.\n",
-		       error);
-		goto err_unregister;
-	}
-
-	return 0;
-
-err_unregister:
-	unregister_efivars(&__efivars);
-err_put:
-	kobject_put(efi_kobj);
-	return error;
-}
-
-static void __exit
-efivars_exit(void)
-{
-	cancel_work_sync(&efivar_work);
-
-	if (efi_enabled(EFI_RUNTIME_SERVICES)) {
-		unregister_efivars(&__efivars);
-		kobject_put(efi_kobj);
-	}
-}
-
-module_init(efivars_init);
-module_exit(efivars_exit);
-

drivers/firmware/google/gsmi.c

@@ -28,6 +28,7 @@
 #include <linux/reboot.h>
 #include <linux/efi.h>
 #include <linux/module.h>
+#include <linux/ucs2_string.h>
 
 #define GSMI_SHUTDOWN_CLEAN	0	/* Clean Shutdown */
 /* TODO(mikew@google.com): Tie in HARDLOCKUP_DETECTOR with NMIWDT */
@@ -288,17 +289,6 @@ static int gsmi_exec(u8 func, u8 sub)
 	return rc;
 }
 
-/* Return the number of unicode characters in data */
-static size_t
-utf16_strlen(efi_char16_t *data, unsigned long maxlength)
-{
-	unsigned long length = 0;
-
-	while (*data++ != 0 && length < maxlength)
-		length++;
-	return length;
-}
-
 static efi_status_t gsmi_get_variable(efi_char16_t *name,
 				      efi_guid_t *vendor, u32 *attr,
 				      unsigned long *data_size,
@@ -311,7 +301,7 @@ static efi_status_t gsmi_get_variable(efi_char16_t *name,
 	};
 	efi_status_t ret = EFI_SUCCESS;
 	unsigned long flags;
-	size_t name_len = utf16_strlen(name, GSMI_BUF_SIZE / 2);
+	size_t name_len = ucs2_strnlen(name, GSMI_BUF_SIZE / 2);
 	int rc;
 
 	if (name_len >= GSMI_BUF_SIZE / 2)
@@ -380,7 +370,7 @@ static efi_status_t gsmi_get_next_variable(unsigned long *name_size,
 		return EFI_BAD_BUFFER_SIZE;
 
 	/* Let's make sure the thing is at least null-terminated */
-	if (utf16_strlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2)
+	if (ucs2_strnlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2)
 		return EFI_INVALID_PARAMETER;
 
 	spin_lock_irqsave(&gsmi_dev.lock, flags);
@@ -408,7 +398,7 @@ static efi_status_t gsmi_get_next_variable(unsigned long *name_size,
 
 		/* Copy the name back */
 		memcpy(name, gsmi_dev.name_buf->start, GSMI_BUF_SIZE);
-		*name_size = utf16_strlen(name, GSMI_BUF_SIZE / 2) * 2;
+		*name_size = ucs2_strnlen(name, GSMI_BUF_SIZE / 2) * 2;
 
 		/* copy guid to return buffer */
 		memcpy(vendor, &param.guid, sizeof(param.guid));
@@ -434,7 +424,7 @@ static efi_status_t gsmi_set_variable(efi_char16_t *name,
 			      EFI_VARIABLE_BOOTSERVICE_ACCESS |
 			      EFI_VARIABLE_RUNTIME_ACCESS,
 	};
-	size_t name_len = utf16_strlen(name, GSMI_BUF_SIZE / 2);
+	size_t name_len = ucs2_strnlen(name, GSMI_BUF_SIZE / 2);
 	efi_status_t ret = EFI_SUCCESS;
 	int rc;
 	unsigned long flags;
@@ -893,12 +883,19 @@ static __init int gsmi_init(void)
 		goto out_remove_bin_file;
 	}
 
-	ret = register_efivars(&efivars, &efivar_ops, gsmi_kobj);
+	ret = efivars_register(&efivars, &efivar_ops, gsmi_kobj);
 	if (ret) {
 		printk(KERN_INFO "gsmi: Failed to register efivars\n");
 		goto out_remove_sysfs_files;
 	}
 
+	ret = efivars_sysfs_init();
+	if (ret) {
+		printk(KERN_INFO "gsmi: Failed to create efivars files\n");
+		efivars_unregister(&efivars);
+		goto out_remove_sysfs_files;
+	}
+
 	register_reboot_notifier(&gsmi_reboot_notifier);
 	register_die_notifier(&gsmi_die_notifier);
 	atomic_notifier_chain_register(&panic_notifier_list,
@@ -930,7 +927,7 @@ static void __exit gsmi_exit(void)
 	unregister_die_notifier(&gsmi_die_notifier);
 	atomic_notifier_chain_unregister(&panic_notifier_list,
 					 &gsmi_panic_notifier);
-	unregister_efivars(&efivars);
+	efivars_unregister(&efivars);
 
 	sysfs_remove_files(gsmi_kobj, gsmi_attrs);
 	sysfs_remove_bin_file(gsmi_kobj, &eventlog_bin_attr);

fs/Kconfig

@@ -211,6 +211,7 @@ source "fs/sysv/Kconfig"
 source "fs/ufs/Kconfig"
 source "fs/exofs/Kconfig"
 source "fs/f2fs/Kconfig"
+source "fs/efivarfs/Kconfig"
 
 endif # MISC_FILESYSTEMS
 

fs/Makefile

@@ -125,3 +125,4 @@ obj-$(CONFIG_F2FS_FS)		+= f2fs/
 obj-y				+= exofs/ # Multiple modules
 obj-$(CONFIG_CEPH_FS)		+= ceph/
 obj-$(CONFIG_PSTORE)		+= pstore/
+obj-$(CONFIG_EFIVAR_FS)		+= efivarfs/

fs/efivarfs/Kconfig

@@ -0,0 +1,12 @@
+config EFIVAR_FS
+	tristate "EFI Variable filesystem"
+	depends on EFI
+	help
+	  efivarfs is a replacement filesystem for the old EFI
+	  variable support via sysfs, as it doesn't suffer from the
+	  same 1024-byte variable size limit.
+
+	  To compile this file system support as a module, choose M
+	  here. The module will be called efivarfs.
+
+	  If unsure, say N.

fs/efivarfs/Makefile

@@ -0,0 +1,7 @@
+#
+# Makefile for the efivarfs filesystem
+#
+
+obj-$(CONFIG_EFIVAR_FS)		+= efivarfs.o
+
+efivarfs-objs			:= inode.o file.o super.o

fs/efivarfs/file.c

@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2012 Red Hat, Inc.
+ * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/efi.h>
+#include <linux/fs.h>
+
+#include "internal.h"
+
+static ssize_t efivarfs_file_write(struct file *file,
+		const char __user *userbuf, size_t count, loff_t *ppos)
+{
+	struct efivar_entry *var = file->private_data;
+	void *data;
+	u32 attributes;
+	struct inode *inode = file->f_mapping->host;
+	unsigned long datasize = count - sizeof(attributes);
+	ssize_t bytes = 0;
+	bool set = false;
+
+	if (count < sizeof(attributes))
+		return -EINVAL;
+
+	if (copy_from_user(&attributes, userbuf, sizeof(attributes)))
+		return -EFAULT;
+
+	if (attributes & ~(EFI_VARIABLE_MASK))
+		return -EINVAL;
+
+	data = kmalloc(datasize, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	if (copy_from_user(data, userbuf + sizeof(attributes), datasize)) {
+		bytes = -EFAULT;
+		goto out;
+	}
+
+	bytes = efivar_entry_set_get_size(var, attributes, &datasize,
+					  data, &set);
+	if (!set && bytes)
+		goto out;
+
+	if (bytes == -ENOENT) {
+		drop_nlink(inode);
+		d_delete(file->f_dentry);
+		dput(file->f_dentry);
+	} else {
+		mutex_lock(&inode->i_mutex);
+		i_size_write(inode, datasize + sizeof(attributes));
+		mutex_unlock(&inode->i_mutex);
+	}
+
+	bytes = count;
+
+out:
+	kfree(data);
+
+	return bytes;
+}
+
+static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf,
+		size_t count, loff_t *ppos)
+{
+	struct efivar_entry *var = file->private_data;
+	unsigned long datasize = 0;
+	u32 attributes;
+	void *data;
+	ssize_t size = 0;
+	int err;
+
+	err = efivar_entry_size(var, &datasize);
+	if (err)
+		return err;
+
+	data = kmalloc(datasize + sizeof(attributes), GFP_KERNEL);
+
+	if (!data)
+		return -ENOMEM;
+
+	size = efivar_entry_get(var, &attributes, &datasize,
+				data + sizeof(attributes));
+	if (size)
+		goto out_free;
+
+	memcpy(data, &attributes, sizeof(attributes));
+	size = simple_read_from_buffer(userbuf, count, ppos,
+				       data, datasize + sizeof(attributes));
+out_free:
+	kfree(data);
+
+	return size;
+}
+
+const struct file_operations efivarfs_file_operations = {
+	.open	= simple_open,
+	.read	= efivarfs_file_read,
+	.write	= efivarfs_file_write,
+	.llseek	= no_llseek,
+};

fs/efivarfs/inode.c

@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2012 Red Hat, Inc.
+ * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/efi.h>
+#include <linux/fs.h>
+#include <linux/ctype.h>
+
+#include "internal.h"
+
+struct inode *efivarfs_get_inode(struct super_block *sb,
+				const struct inode *dir, int mode, dev_t dev)
+{
+	struct inode *inode = new_inode(sb);
+
+	if (inode) {
+		inode->i_ino = get_next_ino();
+		inode->i_mode = mode;
+		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+		switch (mode & S_IFMT) {
+		case S_IFREG:
+			inode->i_fop = &efivarfs_file_operations;
+			break;
+		case S_IFDIR:
+			inode->i_op = &efivarfs_dir_inode_operations;
+			inode->i_fop = &simple_dir_operations;
+			inc_nlink(inode);
+			break;
+		}
+	}
+	return inode;
+}
+
+/*
+ * Return true if 'str' is a valid efivarfs filename of the form,
+ *
+ *	VariableName-12345678-1234-1234-1234-1234567891bc
+ */
+bool efivarfs_valid_name(const char *str, int len)
+{
+	static const char dashes[EFI_VARIABLE_GUID_LEN] = {
+		[8] = 1, [13] = 1, [18] = 1, [23] = 1
+	};
+	const char *s = str + len - EFI_VARIABLE_GUID_LEN;
+	int i;
+
+	/*
+	 * We need a GUID, plus at least one letter for the variable name,
+	 * plus the '-' separator
+	 */
+	if (len < EFI_VARIABLE_GUID_LEN + 2)
+		return false;
+
+	/* GUID must be preceded by a '-' */
+	if (*(s - 1) != '-')
+		return false;
+
+	/*
+	 * Validate that 's' is of the correct format, e.g.
+	 *
+	 *	12345678-1234-1234-1234-123456789abc
+	 */
+	for (i = 0; i < EFI_VARIABLE_GUID_LEN; i++) {
+		if (dashes[i]) {
+			if (*s++ != '-')
+				return false;
+		} else {
+			if (!isxdigit(*s++))
+				return false;
+		}
+	}
+
+	return true;
+}
+
+static void efivarfs_hex_to_guid(const char *str, efi_guid_t *guid)
+{
+	guid->b[0] = hex_to_bin(str[6]) << 4 | hex_to_bin(str[7]);
+	guid->b[1] = hex_to_bin(str[4]) << 4 | hex_to_bin(str[5]);
+	guid->b[2] = hex_to_bin(str[2]) << 4 | hex_to_bin(str[3]);
+	guid->b[3] = hex_to_bin(str[0]) << 4 | hex_to_bin(str[1]);
+	guid->b[4] = hex_to_bin(str[11]) << 4 | hex_to_bin(str[12]);
+	guid->b[5] = hex_to_bin(str[9]) << 4 | hex_to_bin(str[10]);
+	guid->b[6] = hex_to_bin(str[16]) << 4 | hex_to_bin(str[17]);
+	guid->b[7] = hex_to_bin(str[14]) << 4 | hex_to_bin(str[15]);
+	guid->b[8] = hex_to_bin(str[19]) << 4 | hex_to_bin(str[20]);
+	guid->b[9] = hex_to_bin(str[21]) << 4 | hex_to_bin(str[22]);
+	guid->b[10] = hex_to_bin(str[24]) << 4 | hex_to_bin(str[25]);
+	guid->b[11] = hex_to_bin(str[26]) << 4 | hex_to_bin(str[27]);
+	guid->b[12] = hex_to_bin(str[28]) << 4 | hex_to_bin(str[29]);
+	guid->b[13] = hex_to_bin(str[30]) << 4 | hex_to_bin(str[31]);
+	guid->b[14] = hex_to_bin(str[32]) << 4 | hex_to_bin(str[33]);
+	guid->b[15] = hex_to_bin(str[34]) << 4 | hex_to_bin(str[35]);
+}
+
+static int efivarfs_create(struct inode *dir, struct dentry *dentry,
+			  umode_t mode, bool excl)
+{
+	struct inode *inode;
+	struct efivar_entry *var;
+	int namelen, i = 0, err = 0;
+
+	if (!efivarfs_valid_name(dentry->d_name.name, dentry->d_name.len))
+		return -EINVAL;
+
+	inode = efivarfs_get_inode(dir->i_sb, dir, mode, 0);
+	if (!inode)
+		return -ENOMEM;
+
+	var = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL);
+	if (!var) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	/* length of the variable name itself: remove GUID and separator */
+	namelen = dentry->d_name.len - EFI_VARIABLE_GUID_LEN - 1;
+
+	efivarfs_hex_to_guid(dentry->d_name.name + namelen + 1,
+			&var->var.VendorGuid);
+
+	for (i = 0; i < namelen; i++)
+		var->var.VariableName[i] = dentry->d_name.name[i];
+
+	var->var.VariableName[i] = '\0';
+
+	inode->i_private = var;
+
+	efivar_entry_add(var, &efivarfs_list);
+	d_instantiate(dentry, inode);
+	dget(dentry);
+out:
+	if (err) {
+		kfree(var);
+		iput(inode);
+	}
+	return err;
+}
+
+static int efivarfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+	struct efivar_entry *var = dentry->d_inode->i_private;
+
+	if (efivar_entry_delete(var))
+		return -EINVAL;
+
+	drop_nlink(dentry->d_inode);
+	dput(dentry);
+	return 0;
+};
+
+/*
+ * Handle negative dentry.
+ */
+static struct dentry *efivarfs_lookup(struct inode *dir, struct dentry *dentry,
+				      unsigned int flags)
+{
+	if (dentry->d_name.len > NAME_MAX)
+		return ERR_PTR(-ENAMETOOLONG);
+	d_add(dentry, NULL);
+	return NULL;
+}
+
+const struct inode_operations efivarfs_dir_inode_operations = {
+	.lookup = efivarfs_lookup,
+	.unlink = efivarfs_unlink,
+	.create = efivarfs_create,
+};

fs/efivarfs/internal.h

@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2012 Red Hat, Inc.
+ * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef EFIVAR_FS_INTERNAL_H
+#define EFIVAR_FS_INTERNAL_H
+
+#include <linux/list.h>
+
+extern const struct file_operations efivarfs_file_operations;
+extern const struct inode_operations efivarfs_dir_inode_operations;
+extern bool efivarfs_valid_name(const char *str, int len);
+extern struct inode *efivarfs_get_inode(struct super_block *sb,
+			const struct inode *dir, int mode, dev_t dev);
+
+extern struct list_head efivarfs_list;
+
+#endif /* EFIVAR_FS_INTERNAL_H */

fs/efivarfs/super.c

@@ -0,0 +1,268 @@
+/*
+ * Copyright (C) 2012 Red Hat, Inc.
+ * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/ctype.h>
+#include <linux/efi.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/pagemap.h>
+#include <linux/ucs2_string.h>
+
+#include "internal.h"
+
+LIST_HEAD(efivarfs_list);
+
+static void efivarfs_evict_inode(struct inode *inode)
+{
+	clear_inode(inode);
+}
+
+static const struct super_operations efivarfs_ops = {
+	.statfs = simple_statfs,
+	.drop_inode = generic_delete_inode,
+	.evict_inode = efivarfs_evict_inode,
+	.show_options = generic_show_options,
+};
+
+static struct super_block *efivarfs_sb;
+
+/*
+ * Compare two efivarfs file names.
+ *
+ * An efivarfs filename is composed of two parts,
+ *
+ *	1. A case-sensitive variable name
+ *	2. A case-insensitive GUID
+ *
+ * So we need to perform a case-sensitive match on part 1 and a
+ * case-insensitive match on part 2.
+ */
+static int efivarfs_d_compare(const struct dentry *parent, const struct inode *pinode,
+			      const struct dentry *dentry, const struct inode *inode,
+			      unsigned int len, const char *str,
+			      const struct qstr *name)
+{
+	int guid = len - EFI_VARIABLE_GUID_LEN;
+
+	if (name->len != len)
+		return 1;
+
+	/* Case-sensitive compare for the variable name */
+	if (memcmp(str, name->name, guid))
+		return 1;
+
+	/* Case-insensitive compare for the GUID */
+	return strncasecmp(name->name + guid, str + guid, EFI_VARIABLE_GUID_LEN);
+}
+
+static int efivarfs_d_hash(const struct dentry *dentry,
+			   const struct inode *inode, struct qstr *qstr)
+{
+	unsigned long hash = init_name_hash();
+	const unsigned char *s = qstr->name;
+	unsigned int len = qstr->len;
+
+	if (!efivarfs_valid_name(s, len))
+		return -EINVAL;
+
+	while (len-- > EFI_VARIABLE_GUID_LEN)
+		hash = partial_name_hash(*s++, hash);
+
+	/* GUID is case-insensitive. */
+	while (len--)
+		hash = partial_name_hash(tolower(*s++), hash);
+
+	qstr->hash = end_name_hash(hash);
+	return 0;
+}
+
+/*
+ * Retaining negative dentries for an in-memory filesystem just wastes
+ * memory and lookup time: arrange for them to be deleted immediately.
+ */
+static int efivarfs_delete_dentry(const struct dentry *dentry)
+{
+	return 1;
+}
+
+static struct dentry_operations efivarfs_d_ops = {
+	.d_compare = efivarfs_d_compare,
+	.d_hash = efivarfs_d_hash,
+	.d_delete = efivarfs_delete_dentry,
+};
+
+static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name)
+{
+	struct dentry *d;
+	struct qstr q;
+	int err;
+
+	q.name = name;
+	q.len = strlen(name);
+
+	err = efivarfs_d_hash(NULL, NULL, &q);
+	if (err)
+		return ERR_PTR(err);
+
+	d = d_alloc(parent, &q);
+	if (d)
+		return d;
+
+	return ERR_PTR(-ENOMEM);
+}
+
+static int efivarfs_callback(efi_char16_t *name16, efi_guid_t vendor,
+			     unsigned long name_size, void *data)
+{
+	struct super_block *sb = (struct super_block *)data;
+	struct efivar_entry *entry;
+	struct inode *inode = NULL;
+	struct dentry *dentry, *root = sb->s_root;
+	unsigned long size = 0;
+	char *name;
+	int len, i;
+	int err = -ENOMEM;
+
+	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return err;
+
+	memcpy(entry->var.VariableName, name16, name_size);
+	memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
+
+	len = ucs2_strlen(entry->var.VariableName);
+
+	/* name, plus '-', plus GUID, plus NUL*/
+	name = kmalloc(len + 1 + EFI_VARIABLE_GUID_LEN + 1, GFP_KERNEL);
+	if (!name)
+		goto fail;
+
+	for (i = 0; i < len; i++)
+		name[i] = entry->var.VariableName[i] & 0xFF;
+
+	name[len] = '-';
+
+	efi_guid_unparse(&entry->var.VendorGuid, name + len + 1);
+
+	name[len + EFI_VARIABLE_GUID_LEN+1] = '\0';
+
+	inode = efivarfs_get_inode(sb, root->d_inode, S_IFREG | 0644, 0);
+	if (!inode)
+		goto fail_name;
+
+	dentry = efivarfs_alloc_dentry(root, name);
+	if (IS_ERR(dentry)) {
+		err = PTR_ERR(dentry);
+		goto fail_inode;
+	}
+
+	/* copied by the above to local storage in the dentry. */
+	kfree(name);
+
+	efivar_entry_size(entry, &size);
+	efivar_entry_add(entry, &efivarfs_list);
+
+	mutex_lock(&inode->i_mutex);
+	inode->i_private = entry;
+	i_size_write(inode, size + sizeof(entry->var.Attributes));
+	mutex_unlock(&inode->i_mutex);
+	d_add(dentry, inode);
+
+	return 0;
+
+fail_inode:
+	iput(inode);
+fail_name:
+	kfree(name);
+fail:
+	kfree(entry);
+	return err;
+}
+
+static int efivarfs_destroy(struct efivar_entry *entry, void *data)
+{
+	efivar_entry_remove(entry);
+	kfree(entry);
+	return 0;
+}
+
+static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct inode *inode = NULL;
+	struct dentry *root;
+	int err;
+
+	efivarfs_sb = sb;
+
+	sb->s_maxbytes          = MAX_LFS_FILESIZE;
+	sb->s_blocksize         = PAGE_CACHE_SIZE;
+	sb->s_blocksize_bits    = PAGE_CACHE_SHIFT;
+	sb->s_magic             = EFIVARFS_MAGIC;
+	sb->s_op                = &efivarfs_ops;
+	sb->s_d_op		= &efivarfs_d_ops;
+	sb->s_time_gran         = 1;
+
+	inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0);
+	if (!inode)
+		return -ENOMEM;
+	inode->i_op = &efivarfs_dir_inode_operations;
+
+	root = d_make_root(inode);
+	sb->s_root = root;
+	if (!root)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&efivarfs_list);
+
+	err = efivar_init(efivarfs_callback, (void *)sb, false,
+			  true, &efivarfs_list);
+	if (err)
+		__efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL);
+
+	return err;
+}
+
+static struct dentry *efivarfs_mount(struct file_system_type *fs_type,
+				    int flags, const char *dev_name, void *data)
+{
+	return mount_single(fs_type, flags, data, efivarfs_fill_super);
+}
+
+static void efivarfs_kill_sb(struct super_block *sb)
+{
+	kill_litter_super(sb);
+	efivarfs_sb = NULL;
+
+	/* Remove all entries and destroy */
+	__efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL);
+}
+
+static struct file_system_type efivarfs_type = {
+	.name    = "efivarfs",
+	.mount   = efivarfs_mount,
+	.kill_sb = efivarfs_kill_sb,
+};
+
+static __init int efivarfs_init(void)
+{
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		return 0;
+
+	if (!efivars_kobject())
+		return 0;
+
+	return register_filesystem(&efivarfs_type);
+}
+
+MODULE_AUTHOR("Matthew Garrett, Jeremy Kerr");
+MODULE_DESCRIPTION("EFI Variable Filesystem");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_FS("efivarfs");
+
+module_init(efivarfs_init);

include/linux/efi.h

@@ -669,6 +669,12 @@ static inline int efi_enabled(int facility)
 				EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | \
 				EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS | \
 				EFI_VARIABLE_APPEND_WRITE)
+/*
+ * Length of a GUID string (strlen("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee"))
+ * not including trailing NUL
+ */
+#define EFI_VARIABLE_GUID_LEN 36
+
 /*
  * The type of search to perform when calling boottime->locate_handle
  */
@@ -726,7 +732,6 @@ static inline void memrange_efi_to_native(u64 *addr, u64 *npages)
 	*addr &= PAGE_MASK;
 }
 
-#if defined(CONFIG_EFI_VARS) || defined(CONFIG_EFI_VARS_MODULE)
 /*
  * EFI Variable support.
  *
@@ -752,19 +757,88 @@ struct efivars {
 	 * which is protected by the BKL, so that path is safe.
 	 */
 	spinlock_t lock;
-	struct list_head list;
 	struct kset *kset;
 	struct kobject *kobject;
-	struct bin_attribute *new_var, *del_var;
 	const struct efivar_operations *ops;
-	struct efivar_entry *walk_entry;
-	struct pstore_info efi_pstore_info;
 };
 
-int register_efivars(struct efivars *efivars,
+/*
+ * The maximum size of VariableName + Data = 1024
+ * Therefore, it's reasonable to save that much
+ * space in each part of the structure,
+ * and we use a page for reading/writing.
+ */
+
+struct efi_variable {
+	efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
+	efi_guid_t    VendorGuid;
+	unsigned long DataSize;
+	__u8          Data[1024];
+	efi_status_t  Status;
+	__u32         Attributes;
+} __attribute__((packed));
+
+struct efivar_entry {
+	struct efi_variable var;
+	struct list_head list;
+	struct kobject kobj;
+};
+
+extern struct list_head efivar_sysfs_list;
+
+static inline void
+efivar_unregister(struct efivar_entry *var)
+{
+	kobject_put(&var->kobj);
+}
+
+int efivars_register(struct efivars *efivars,
 		     const struct efivar_operations *ops,
-		     struct kobject *parent_kobj);
-void unregister_efivars(struct efivars *efivars);
+		     struct kobject *kobject);
+int efivars_unregister(struct efivars *efivars);
+struct kobject *efivars_kobject(void);
+
+int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *),
+		void *data, bool atomic, bool duplicates,
+		struct list_head *head);
+
+void efivar_entry_add(struct efivar_entry *entry, struct list_head *head);
+void efivar_entry_remove(struct efivar_entry *entry);
+
+int __efivar_entry_delete(struct efivar_entry *entry);
+int efivar_entry_delete(struct efivar_entry *entry);
+
+int efivar_entry_size(struct efivar_entry *entry, unsigned long *size);
+int __efivar_entry_get(struct efivar_entry *entry, u32 *attributes,
+		       unsigned long *size, void *data);
+int efivar_entry_get(struct efivar_entry *entry, u32 *attributes,
+		     unsigned long *size, void *data);
+int efivar_entry_set(struct efivar_entry *entry, u32 attributes,
+		     unsigned long size, void *data, struct list_head *head);
+int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes,
+			      unsigned long *size, void *data, bool *set);
+int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes,
+			  bool block, unsigned long size, void *data);
+
+void efivar_entry_iter_begin(void);
+void efivar_entry_iter_end(void);
+
+int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *),
+			struct list_head *head, void *data,
+			struct efivar_entry **prev);
+int efivar_entry_iter(int (*func)(struct efivar_entry *, void *),
+		      struct list_head *head, void *data);
+
+struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid,
+				       struct list_head *head, bool remove);
+
+bool efivar_validate(struct efi_variable *var, u8 *data, unsigned long len);
+
+extern struct work_struct efivar_work;
+void efivar_run_worker(void);
+
+#if defined(CONFIG_EFI_VARS) || defined(CONFIG_EFI_VARS_MODULE)
+int efivars_sysfs_init(void);
 
 #endif /* CONFIG_EFI_VARS */