diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-16 13:06:27 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-16 13:06:27 -0700 |
commit | 49817c33433a3cd6f320b13699e6746cc39b453b (patch) | |
tree | 1eb8c4a4d585e648b0783741c02ab611149971d9 /drivers/firmware/efi/efibc.c | |
parent | 230e51f21101e49c8d73018d414adbd0d57459a1 (diff) | |
parent | 6c5450ef66816216e574885cf8d3ddb31ef77428 (diff) |
Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
"The main changes in this cycle were:
- Drop the unused EFI_SYSTEM_TABLES efi.flags bit and ensure the
ARM/arm64 EFI System Table mapping is read-only (Ard Biesheuvel)
- Add a comment to explain that one of the code paths in the x86/pat
code is only executed for EFI boot (Matt Fleming)
- Improve Secure Boot status checks on arm64 and handle unexpected
errors (Linn Crosetto)
- Remove the global EFI memory map variable 'memmap' as the same
information is already available in efi::memmap (Matt Fleming)
- Add EFI Memory Attribute table support for ARM/arm64 (Ard
Biesheuvel)
- Add EFI GOP framebuffer support for ARM/arm64 (Ard Biesheuvel)
- Add EFI Bootloader Control driver for storing reboot(2) data in EFI
variables for consumption by bootloaders (Jeremy Compostella)
- Add Core EFI capsule support (Matt Fleming)
- Add EFI capsule char driver (Kweh, Hock Leong)
- Unify EFI memory map code for ARM and arm64 (Ard Biesheuvel)
- Add generic EFI support for detecting when firmware corrupts CPU
status register bits (like IRQ flags) when performing EFI runtime
service calls (Mark Rutland)
... and other misc cleanups"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
efivarfs: Make efivarfs_file_ioctl() static
efi: Merge boolean flag arguments
efi/capsule: Move 'capsule' to the stack in efi_capsule_supported()
efibc: Fix excessive stack footprint warning
efi/capsule: Make efi_capsule_pending() lockless
efi: Remove unnecessary (and buggy) .memmap initialization from the Xen EFI driver
efi/runtime-wrappers: Remove ARCH_EFI_IRQ_FLAGS_MASK #ifdef
x86/efi: Enable runtime call flag checking
arm/efi: Enable runtime call flag checking
arm64/efi: Enable runtime call flag checking
efi/runtime-wrappers: Detect firmware IRQ flag corruption
efi/runtime-wrappers: Remove redundant #ifdefs
x86/efi: Move to generic {__,}efi_call_virt()
arm/efi: Move to generic {__,}efi_call_virt()
arm64/efi: Move to generic {__,}efi_call_virt()
efi/runtime-wrappers: Add {__,}efi_call_virt() templates
efi/arm-init: Reserve rather than unmap the memory map for ARM as well
efi: Add misc char driver interface to update EFI firmware
x86/efi: Force EFI reboot to process pending capsules
efi: Add 'capsule' update support
...
Diffstat (limited to 'drivers/firmware/efi/efibc.c')
-rw-r--r-- | drivers/firmware/efi/efibc.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/drivers/firmware/efi/efibc.c b/drivers/firmware/efi/efibc.c new file mode 100644 index 000000000000..8dd0c7085e59 --- /dev/null +++ b/drivers/firmware/efi/efibc.c @@ -0,0 +1,113 @@ +/* + * efibc: control EFI bootloaders which obey LoaderEntryOneShot var + * Copyright (c) 2013-2016, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + */ + +#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"); + return -EINVAL; + } + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) { + pr_err("failed to allocate efivar entry"); + 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"); |