Commit b9394d8a authored by Linus Torvalds's avatar Linus Torvalds

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()
parents 126de6b2 7b2dd6d2
......@@ -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
......
......@@ -110,6 +110,7 @@ config DMI
config EFI
bool
select UCS2_STRING
default y
config SCHED_OMIT_FRAME_POINTER
......
......@@ -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.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;
......
......@@ -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
......@@ -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-$(CONFIG_EFI) += efi/
menu "EFI (Extensible Firmware Interface) Support"
depends on EFI
config EFI_VARS
tristate "EFI Variable Support via sysfs"
depends on EFI
default n
help
If you say Y here, you are able to get EFI (Extensible Firmware
Interface) variable information via sysfs. You may read,
write, create, and destroy EFI variables through this interface.
Note that using this driver in concert with efibootmgr requires
at least test release version 0.5.0-test3 or later, which is
available from Matt Domsch's website located at:
<http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz>
Subsequent efibootmgr releases may be found at:
<http://linux.dell.com/efibootmgr>
config EFI_VARS_PSTORE
tristate "Register efivars backend for pstore"
depends on EFI_VARS && PSTORE
default y
help
Say Y here to enable use efivars as a backend to pstore. This
will allow writing console messages, crash dumps, or anything
else supported by pstore to EFI variables.
config EFI_VARS_PSTORE_DEFAULT_DISABLE
bool "Disable using efivars as a pstore backend by default"
depends on EFI_VARS_PSTORE
default n
help
Saying Y here will disable the use of efivars as a storage
backend for pstore by default. This setting can be overridden
using the efivars module's pstore_disable parameter.
endmenu
#
# Makefile for linux kernel
#
obj-y += efi.o vars.o
obj-$(CONFIG_EFI_VARS) += efivars.o
obj-$(CONFIG_EFI_VARS_PSTORE) += efi-pstore.o
#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");
/*
* 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);
/*
* 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);
/*
* 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);
/*
* 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);
......@@ -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);
......
......@@ -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
......
......@@ -125,3 +125,4 @@ obj-$(CONFIG_F2FS_FS) += f2fs/
obj-y += exofs/ # Multiple modules
obj-$(CONFIG_CEPH_FS) += ceph/
obj-$(CONFIG_PSTORE) += pstore/
obj-$(CONFIG_EFIVAR_FS) += efivarfs/
config EFIVAR_FS
tristate "EFI Variable filesystem"
depends on EFI
help
efivarfs is a replacement filesystem for the old EFI
variable support via sysfs, as it doesn't suffer from the
same 1024-byte variable size limit.
To compile this file system support as a module, choose M
here. The module will be called efivarfs.
If unsure, say N.
#
# Makefile for the efivarfs filesystem
#
obj-$(CONFIG_EFIVAR_FS) += efivarfs.o
efivarfs-objs := inode.o file.o super.o
/*
* 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,
};
/*
* 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,
};
/*
* 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 */
/*
* 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);
......@@ -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 */
......
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