linux/drivers/firmware/efi/efibc.c
Ard Biesheuvel 4febfb8dd0 efi: Replace GPL license boilerplate with SPDX headers
Replace all GPL license blurbs with an equivalent SPDX header (most
files are GPLv2, some are GPLv2+). While at it, drop some outdated
header changelogs as well.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190202094119.13230-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:27:25 +01:00

106 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* efibc: control EFI bootloaders which obey LoaderEntryOneShot var
* Copyright (c) 2013-2016, Intel Corporation.
*/
#define pr_fmt(fmt) "efibc: " fmt
#include <linux/efi.h>
#include <linux/module.h>
#include <linux/reboot.h>
#include <linux/slab.h>
static void efibc_str_to_str16(const char *str, efi_char16_t *str16)
{
size_t i;
for (i = 0; i < strlen(str); i++)
str16[i] = str[i];
str16[i] = '\0';
}
static int efibc_set_variable(const char *name, const char *value)
{
int ret;
efi_guid_t guid = LINUX_EFI_LOADER_ENTRY_GUID;
struct efivar_entry *entry;
size_t size = (strlen(value) + 1) * sizeof(efi_char16_t);
if (size > sizeof(entry->var.Data)) {
pr_err("value is too large (%zu bytes) for '%s' EFI variable\n", size, name);
return -EINVAL;
}
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
if (!entry) {
pr_err("failed to allocate efivar entry for '%s' EFI variable\n", name);
return -ENOMEM;
}
efibc_str_to_str16(name, entry->var.VariableName);
efibc_str_to_str16(value, (efi_char16_t *)entry->var.Data);
memcpy(&entry->var.VendorGuid, &guid, sizeof(guid));
ret = efivar_entry_set(entry,
EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS,
size, entry->var.Data, NULL);
if (ret)
pr_err("failed to set %s EFI variable: 0x%x\n",
name, ret);
kfree(entry);
return ret;
}
static int efibc_reboot_notifier_call(struct notifier_block *notifier,
unsigned long event, void *data)
{
const char *reason = "shutdown";
int ret;
if (event == SYS_RESTART)
reason = "reboot";
ret = efibc_set_variable("LoaderEntryRebootReason", reason);
if (ret || !data)
return NOTIFY_DONE;
efibc_set_variable("LoaderEntryOneShot", (char *)data);
return NOTIFY_DONE;
}
static struct notifier_block efibc_reboot_notifier = {
.notifier_call = efibc_reboot_notifier_call,
};
static int __init efibc_init(void)
{
int ret;
if (!efi_enabled(EFI_RUNTIME_SERVICES))
return -ENODEV;
ret = register_reboot_notifier(&efibc_reboot_notifier);
if (ret)
pr_err("unable to register reboot notifier\n");
return ret;
}
module_init(efibc_init);
static void __exit efibc_exit(void)
{
unregister_reboot_notifier(&efibc_reboot_notifier);
}
module_exit(efibc_exit);
MODULE_AUTHOR("Jeremy Compostella <jeremy.compostella@intel.com>");
MODULE_AUTHOR("Matt Gumbel <matthew.k.gumbel@intel.com");
MODULE_DESCRIPTION("EFI Bootloader Control");
MODULE_LICENSE("GPL v2");