diff options
| -rw-r--r-- | MAINTAINERS | 13 | ||||
| -rw-r--r-- | arch/ia64/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi.c | 19 | ||||
| -rw-r--r-- | drivers/firmware/Kconfig | 37 | ||||
| -rw-r--r-- | drivers/firmware/Makefile | 2 | ||||
| -rw-r--r-- | drivers/firmware/efi/Kconfig | 39 | ||||
| -rw-r--r-- | drivers/firmware/efi/Makefile | 6 | ||||
| -rw-r--r-- | drivers/firmware/efi/efi-pstore.c | 251 | ||||
| -rw-r--r-- | drivers/firmware/efi/efi.c | 134 | ||||
| -rw-r--r-- | drivers/firmware/efi/efivars.c | 616 | ||||
| -rw-r--r-- | drivers/firmware/efi/vars.c | 1041 | ||||
| -rw-r--r-- | drivers/firmware/efivars.c | 2117 | ||||
| -rw-r--r-- | drivers/firmware/google/gsmi.c | 31 | ||||
| -rw-r--r-- | fs/Kconfig | 1 | ||||
| -rw-r--r-- | fs/Makefile | 1 | ||||
| -rw-r--r-- | fs/efivarfs/Kconfig | 12 | ||||
| -rw-r--r-- | fs/efivarfs/Makefile | 7 | ||||
| -rw-r--r-- | fs/efivarfs/file.c | 105 | ||||
| -rw-r--r-- | fs/efivarfs/inode.c | 173 | ||||
| -rw-r--r-- | fs/efivarfs/internal.h | 22 | ||||
| -rw-r--r-- | fs/efivarfs/super.c | 268 | ||||
| -rw-r--r-- | include/linux/efi.h | 90 |
22 files changed, 2796 insertions, 2190 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 46ccc20892a..ee468fac7db 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3025,9 +3025,18 @@ F: arch/ia64/kernel/efi.c F: arch/x86/boot/compressed/eboot.[ch] F: arch/x86/include/asm/efi.h F: arch/x86/platform/efi/* -F: drivers/firmware/efivars.c +F: drivers/firmware/efi/* F: include/linux/efi*.h +EFI VARIABLE FILESYSTEM +M: Matthew Garrett <matthew.garrett@nebula.com> +M: Jeremy Kerr <jk@ozlabs.org> +M: Matt Fleming <matt.fleming@intel.com> +T: git git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git +L: linux-efi@vger.kernel.org +S: Maintained +F: fs/efivarfs/ + EFIFB FRAMEBUFFER DRIVER L: linux-fbdev@vger.kernel.org M: Peter Jones <pjones@redhat.com> @@ -6391,7 +6400,7 @@ S: Maintained T: git git://git.infradead.org/users/cbou/linux-pstore.git F: fs/pstore/ F: include/linux/pstore* -F: drivers/firmware/efivars.c +F: drivers/firmware/efi/efi-pstore.c F: drivers/acpi/apei/erst.c PTP HARDWARE CLOCK SUPPORT diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index e725ea01569..d393f841ff5 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -110,6 +110,7 @@ config DMI config EFI bool + select UCS2_STRING default y config SCHED_OMIT_FRAME_POINTER diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index b55d174e503..6b85db0a7cc 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -453,24 +453,25 @@ static void __init do_add_efi_memmap(void) int __init efi_memblock_x86_reserve_range(void) { + struct efi_info *e = &boot_params.efi_info; unsigned long pmap; #ifdef CONFIG_X86_32 /* Can't handle data above 4GB at this time */ - if (boot_params.efi_info.efi_memmap_hi) { + if (e->efi_memmap_hi) { pr_err("Memory map is above 4GB, disabling EFI.\n"); return -EINVAL; } - pmap = boot_params.efi_info.efi_memmap; + pmap = e->efi_memmap; #else - pmap = (boot_params.efi_info.efi_memmap | - ((__u64)boot_params.efi_info.efi_memmap_hi<<32)); + pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32)); #endif - memmap.phys_map = (void *)pmap; - memmap.nr_map = boot_params.efi_info.efi_memmap_size / - boot_params.efi_info.efi_memdesc_size; - memmap.desc_version = boot_params.efi_info.efi_memdesc_version; - memmap.desc_size = boot_params.efi_info.efi_memdesc_size; + memmap.phys_map = (void *)pmap; + memmap.nr_map = e->efi_memmap_size / + e->efi_memdesc_size; + memmap.desc_size = e->efi_memdesc_size; + memmap.desc_version = e->efi_memdesc_version; + memblock_reserve(pmap, memmap.nr_map * memmap.desc_size); return 0; diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index 3e532002e4d..93876302fb2 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -36,42 +36,6 @@ config FIRMWARE_MEMMAP See also Documentation/ABI/testing/sysfs-firmware-memmap. -config EFI_VARS - tristate "EFI Variable Support via sysfs" - depends on EFI - select UCS2_STRING - default n - help - If you say Y here, you are able to get EFI (Extensible Firmware - Interface) variable information via sysfs. You may read, - write, create, and destroy EFI variables through this interface. - - Note that using this driver in concert with efibootmgr requires - at least test release version 0.5.0-test3 or later, which is - available from Matt Domsch's website located at: - <http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz> - - Subsequent efibootmgr releases may be found at: - <http://linux.dell.com/efibootmgr> - -config EFI_VARS_PSTORE - bool "Register efivars backend for pstore" - depends on EFI_VARS && PSTORE - default y - help - Say Y here to enable use efivars as a backend to pstore. This - will allow writing console messages, crash dumps, or anything - else supported by pstore to EFI variables. - -config EFI_VARS_PSTORE_DEFAULT_DISABLE - bool "Disable using efivars as a pstore backend by default" - depends on EFI_VARS_PSTORE - default n - help - Saying Y here will disable the use of efivars as a storage - backend for pstore by default. This setting can be overridden - using the efivars module's pstore_disable parameter. - config EFI_PCDP bool "Console device selection via EFI PCDP or HCDP table" depends on ACPI && EFI && IA64 @@ -165,5 +129,6 @@ config ISCSI_IBFT Otherwise, say N. source "drivers/firmware/google/Kconfig" +source "drivers/firmware/efi/Kconfig" endmenu diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index 5a7e2739972..299fad6b586 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -4,7 +4,6 @@ obj-$(CONFIG_DMI) += dmi_scan.o obj-$(CONFIG_DMI_SYSFS) += dmi-sysfs.o obj-$(CONFIG_EDD) += edd.o -obj-$(CONFIG_EFI_VARS) += efivars.o obj-$(CONFIG_EFI_PCDP) += pcdp.o obj-$(CONFIG_DELL_RBU) += dell_rbu.o obj-$(CONFIG_DCDBAS) += dcdbas.o @@ -14,3 +13,4 @@ obj-$(CONFIG_ISCSI_IBFT) += iscsi_ibft.o obj-$(CONFIG_FIRMWARE_MEMMAP) += memmap.o obj-$(CONFIG_GOOGLE_FIRMWARE) += google/ +obj-$(CONFIG_EFI) += efi/ diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig new file mode 100644 index 00000000000..b0fc7c79dfb --- /dev/null +++ b/drivers/firmware/efi/Kconfig @@ -0,0 +1,39 @@ +menu "EFI (Extensible Firmware Interface) Support" + depends on EFI + +config EFI_VARS + tristate "EFI Variable Support via sysfs" + depends on EFI + default n + help + If you say Y here, you are able to get EFI (Extensible Firmware + Interface) variable information via sysfs. You may read, + write, create, and destroy EFI variables through this interface. + + Note that using this driver in concert with efibootmgr requires + at least test release version 0.5.0-test3 or later, which is + available from Matt Domsch's website located at: + <http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz> + + Subsequent efibootmgr releases may be found at: + <http://linux.dell.com/efibootmgr> + +config EFI_VARS_PSTORE + tristate "Register efivars backend for pstore" + depends on EFI_VARS && PSTORE + default y + help + Say Y here to enable use efivars as a backend to pstore. This + will allow writing console messages, crash dumps, or anything + else supported by pstore to EFI variables. + +config EFI_VARS_PSTORE_DEFAULT_DISABLE + bool "Disable using efivars as a pstore backend by default" + depends on EFI_VARS_PSTORE + default n + help + Saying Y here will disable the use of efivars as a storage + backend for pstore by default. This setting can be overridden + using the efivars module's pstore_disable parameter. + +endmenu diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile new file mode 100644 index 00000000000..99245ab5a79 --- /dev/null +++ b/drivers/firmware/efi/Makefile @@ -0,0 +1,6 @@ +# +# Makefile for linux kernel +# +obj-y += efi.o vars.o +obj-$(CONFIG_EFI_VARS) += efivars.o +obj-$(CONFIG_EFI_VARS_PSTORE) += efi-pstore.o diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c new file mode 100644 index 00000000000..67615d6d038 --- /dev/null +++ b/drivers/firmware/efi/efi-pstore.c @@ -0,0 +1,251 @@ +#include <linux/efi.h> +#include <linux/module.h> +#include <linux/pstore.h> +#include <linux/ucs2_string.h> + +#define DUMP_NAME_LEN 52 + +static bool efivars_pstore_disable = + IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE); + +module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644); + +#define PSTORE_EFI_ATTRIBUTES \ + (EFI_VARIABLE_NON_VOLATILE | \ + EFI_VARIABLE_BOOTSERVICE_ACCESS | \ + EFI_VARIABLE_RUNTIME_ACCESS) + +static int efi_pstore_open(struct pstore_info *psi) +{ + efivar_entry_iter_begin(); + psi->data = NULL; + return 0; +} + +static int efi_pstore_close(struct pstore_info *psi) +{ + efivar_entry_iter_end(); + psi->data = NULL; + return 0; +} + +struct pstore_read_data { + u64 *id; + enum pstore_type_id *type; + int *count; + struct timespec *timespec; + char **buf; +}; + +static int efi_pstore_read_func(struct efivar_entry *entry, void *data) +{ + efi_guid_t vendor = LINUX_EFI_CRASH_GUID; + struct pstore_read_data *cb_data = data; + char name[DUMP_NAME_LEN]; + int i; + int cnt; + unsigned int part; + unsigned long time, size; + + if (efi_guidcmp(entry->var.VendorGuid, vendor)) + return 0; + + for (i = 0; i < DUMP_NAME_LEN; i++) + name[i] = entry->var.VariableName[i]; + + if (sscanf(name, "dump-type%u-%u-%d-%lu", + cb_data->type, &part, &cnt, &time) == 4) { + *cb_data->id = part; + *cb_data->count = cnt; + cb_data->timespec->tv_sec = time; + cb_data->timespec->tv_nsec = 0; + } else if (sscanf(name, "dump-type%u-%u-%lu", + cb_data->type, &part, &time) == 3) { + /* + * Check if an old format, + * which doesn't support holding + * multiple logs, remains. + */ + *cb_data->id = part; + *cb_data->count = 0; + cb_data->timespec->tv_sec = time; + cb_data->timespec->tv_nsec = 0; + } else + return 0; + + entry->var.DataSize = 1024; + __efivar_entry_get(entry, &entry->var.Attributes, + &entry->var.DataSize, entry->var.Data); + size = entry->var.DataSize; + + *cb_data->buf = kmalloc(size, GFP_KERNEL); + if (*cb_data->buf == NULL) + return -ENOMEM; + memcpy(*cb_data->buf, entry->var.Data, size); + return size; +} + +static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, + int *count, struct timespec *timespec, + char **buf, struct pstore_info *psi) +{ + struct pstore_read_data data; + + data.id = id; + data.type = type; + data.count = count; + data.timespec = timespec; + data.buf = buf; + + return __efivar_entry_iter(efi_pstore_read_func, &efivar_sysfs_list, &data, + (struct efivar_entry **)&psi->data); +} + +static int efi_pstore_write(enum pstore_type_id type, + enum kmsg_dump_reason reason, u64 *id, + unsigned int part, int count, size_t size, + struct pstore_info *psi) +{ + char name[DUMP_NAME_LEN]; + efi_char16_t efi_name[DUMP_NAME_LEN]; + efi_guid_t vendor = LINUX_EFI_CRASH_GUID; + int i, ret = 0; + + sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count, + get_seconds()); + + for (i = 0; i < DUMP_NAME_LEN; i++) + efi_name[i] = name[i]; + + efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES, + !pstore_cannot_block_path(reason), + size, psi->buf); + + if (reason == KMSG_DUMP_OOPS) + efivar_run_worker(); + + *id = part; + return ret; +}; + +struct pstore_erase_data { + u64 id; + enum pstore_type_id type; + int count; + struct timespec time; + efi_char16_t *name; +}; + +/* + * Clean up an entry with the same name + */ +static int efi_pstore_erase_func(struct efivar_entry *entry, void *data) +{ + struct pstore_erase_data *ed = data; + efi_guid_t vendor = LINUX_EFI_CRASH_GUID; + efi_char16_t efi_name_old[DUMP_NAME_LEN]; + efi_char16_t *efi_name = ed->name; + unsigned long ucs2_len = ucs2_strlen(ed->name); + char name_old[DUMP_NAME_LEN]; + int i; + + if (efi_guidcmp(entry->var.VendorGuid, vendor)) + return 0; + + if (ucs2_strncmp(entry->var.VariableName, + efi_name, (size_t)ucs2_len)) { + /* + * Check if an old format, which doesn't support + * holding multiple logs, remains. + */ + sprintf(name_old, "dump-type%u-%u-%lu", ed->type, + (unsigned int)ed->id, ed->time.tv_sec); + + for (i = 0; i < DUMP_NAME_LEN; i++) + efi_name_old[i] = name_old[i]; + + if (ucs2_strncmp(entry->var.VariableName, efi_name_old, + ucs2_strlen(efi_name_old))) + return 0; + } + + /* found */ + __efivar_entry_delete(entry); + list_del(&entry->list); + + return 1; +} + +static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, + struct timespec time, struct pstore_info *psi) +{ + struct pstore_erase_data edata; + struct efivar_entry *entry = NULL; + char name[DUMP_NAME_LEN]; + efi_char16_t efi_name[DUMP_NAME_LEN]; + int found, i; + + sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count, + time.tv_sec); + + for (i = 0; i < DUMP_NAME_LEN; i++) + efi_name[i] = name[i]; + + edata.id = id; + edata.type = type; + edata.count = count; + edata.time = time; + edata.name = efi_name; + + efivar_entry_iter_begin(); + found = __efivar_entry_iter(efi_pstore_erase_func, &efivar_sysfs_list, &edata, &entry); + efivar_entry_iter_end(); + + if (found) + efivar_unregister(entry); + + return 0; +} + +static struct pstore_info efi_pstore_info = { + .owner = THIS_MODULE, + .name = "efi", + .open = efi_pstore_open, + .close = efi_pstore_close, + .read = efi_pstore_read, + .write = efi_pstore_write, + .erase = efi_pstore_erase, +}; + +static __init int efivars_pstore_init(void) +{ + if (!efi_enabled(EFI_RUNTIME_SERVICES)) + return 0; + + if (!efivars_kobject()) + return 0; + + if (efivars_pstore_disable) + return 0; + + efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL); + if (!efi_pstore_info.buf) + return -ENOMEM; + + efi_pstore_info.bufsize = 1024; + spin_lock_init(&efi_pstore_info.buf_lock); + + pstore_register(&efi_pstore_info); + + return 0; +} + +static __exit void efivars_pstore_exit(void) +{ +} + +module_init(efivars_pstore_init); +module_exit(efivars_pstore_exit); + +MODULE_DESCRIPTION("EFI variable backend for pstore"); +MODULE_LICENSE("GPL"); diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c new file mode 100644 index 00000000000..5145fa344ad --- /dev/null +++ b/drivers/firmware/efi/efi.c @@ -0,0 +1,134 @@ +/* + * efi.c - EFI subsystem + * + * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> + * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> + * Copyright (C) 2013 Tom Gundersen <teg@jklm.no> + * + * This code registers /sys/firmware/efi{,/efivars} when EFI is supported, + * allowing the efivarfs to be mounted or the efivars module to be loaded. + * The existance of /sys/firmware/efi may also be used by userspace to + * determine that the system supports EFI. + * + * This file is released under the GPLv2. + */ + +#include <linux/kobject.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/device.h> +#include <linux/efi.h> + +static struct kobject *efi_kobj; +static struct kobject *efivars_kobj; + +/* + * Let's not leave out systab information that snuck into + * the efivars driver + */ +static ssize_t systab_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + char *str = buf; + + if (!kobj || !buf) + return -EINVAL; + + if (efi.mps != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "MPS=0x%lx\n", efi.mps); + if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); + if (efi.acpi != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); + if (efi.smbios != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); + if (efi.hcdp != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp); + if (efi.boot_info != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info); + if (efi.uga != EFI_INVALID_TABLE_ADDR) + str += sprintf(str, "UGA=0x%lx\n", efi.uga); + + return str - buf; +} + +static struct kobj_attribute efi_attr_systab = + __ATTR(systab, 0400, systab_show, NULL); + +static struct attribute *efi_subsys_attrs[] = { + &efi_attr_systab.attr, + NULL, /* maybe more in the future? */ +}; + +static struct attribute_group efi_subsys_attr_group = { + .attrs = efi_subsys_attrs, +}; + +static struct efivars generic_efivars; +static struct efivar_operations generic_ops; + +static int generic_ops_register(void) +{ + generic_ops.get_variable = efi.get_variable; + generic_ops.set_variable = efi.set_variable; + generic_ops.get_next_variable = efi.get_next_variable; + generic_ops.query_variable_store = efi_query_variable_store; + + return efivars_register(&generic_efivars, &generic_ops, efi_kobj); +} + +static void generic_ops_unregister(void) +{ + efivars_unregister(&generic_efivars); +} + +/* + * We register the efi subsystem with the firmware subsystem and the + * efivars subsystem with the efi subsystem, if the system was booted with + * EFI. + */ +static int __init efisubsys_init(void) +{ + int error; + + if (!efi_enabled(EFI_BOOT)) + return 0; + + /* We register the efi directory at /sys/firmware/efi */ + efi_kobj = kobject_create_and_add("efi", firmware_kobj); + if (!efi_kobj) { + pr_err("efi: Firmware registration failed.\n"); + return -ENOMEM; + } + + error = generic_ops_register(); + if (error) + goto err_put; + + error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); + if (error) { + pr_err("efi: Sysfs attribute export failed with error %d.\n", + error); + goto err_unregister; + } + + /* and the standard mountpoint for efivarfs */ + efivars_kobj = kobject_create_and_add("efivars", efi_kobj); + if (!efivars_kobj) { + pr_err("efivars: Subsystem registration failed.\n"); + error = -ENOMEM; + goto err_remove_group; + } + + return 0; + +err_remove_group: + sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); +err_unregister: + generic_ops_unregister(); +err_put: + kobject_put(efi_kobj); + return error; +} + +subsys_initcall(efisubsys_init); diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c new file mode 100644 index 00000000000..5e94897244c --- /dev/null +++ b/drivers/firmware/efi/efivars.c @@ -0,0 +1,616 @@ +/* + * Originally from efivars.c, + * + * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> + * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> + * + * This code takes all variables accessible from EFI runtime and + * exports them via sysfs + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Changelog: + * + * 17 May 2004 - Matt Domsch <Matt_Domsch@dell.com> + * remove check for efi_enabled in exit + * add MODULE_VERSION + * + * 26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com> + * minor bug fixes + * + * 21 Apr 2004 - Matt Tolentino <matthew.e.tolentino@intel.com) + * converted driver to export variable information via sysfs + * and moved to drivers/firmware directory + * bumped revision number to v0.07 to reflect conversion & move + * + * 10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com> + * fix locking per Peter Chubb's findings + * + * 25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com> + * move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_unparse() + * + * 12 Feb 2002 - Matt Domsch <Matt_Domsch@dell.com> + * use list_for_each_safe when deleting vars. + * remove ifdef CONFIG_SMP around include <linux/smp.h> + * v0.04 release to linux-ia64@linuxia64.org + * + * 20 April 2001 - Matt Domsch <Matt_Domsch@dell.com> + * Moved vars from /proc/efi to /proc/efi/vars, and made + * efi.c own the /proc/efi directory. + * v0.03 release to linux-ia64@linuxia64.org + * + * 26 March 2001 - Matt Domsch <Matt_Domsch@dell.com> + * At the request of Stephane, moved ownership of /proc/efi + * to efi.c, and now efivars lives under /proc/efi/vars. + * + * 12 March 2001 - Matt Domsch <Matt_Domsch@dell.com> + * Feedback received from Stephane Eranian incorporated. + * efivar_write() checks copy_from_user() return value. + * efivar_read/write() returns proper errno. + * v0.02 release to linux-ia64@linuxia64.org + * + * 26 February 2001 - Matt Domsch <Matt_Domsch@dell.com> + * v0.01 release to linux-ia64@linuxia64.org + */ + +#include <linux/efi.h> +#include <linux/module.h> +#include <linux/ucs2_string.h> + +#define EFIVARS_VERSION "0.08" +#define EFIVARS_DATE "2004-May-17" + +MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>"); +MODULE_DESCRIPTION("sysfs interface to EFI Variables"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(EFIVARS_VERSION); + +LIST_HEAD(efivar_sysfs_list); +EXPORT_SYMBOL_GPL(efivar_sysfs_list); + +static struct kset *efivars_kset; + +static struct bin_attribute *efivars_new_var; +static struct bin_attribute *efivars_del_var; + +struct efivar_attribute { + struct attribute attr; + ssize_t (*show) (struct efivar_entry *entry, char *buf); + ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count); +}; + +#define EFIVAR_ATTR(_name, _mode, _show, _store) \ +struct efivar_attribute efivar_attr_##_name = { \ + .attr = {.name = __stringify(_name), .mode = _mode}, \ + .show = _show, \ + .store = _store, \ +}; + +#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr) +#define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj) + +/* + * Prototype for sysfs creation function + */ +static int +efivar_create_sysfs_entry(struct efivar_entry *new_var); + +static ssize_t +efivar_guid_read(struct efivar_entry *entry, char *buf) +{ + struct efi_variable *var = &entry->var; + char *str = buf; + + if (!entry || !buf) + return 0; + + efi_guid_unparse(&var->VendorGuid, str); + str += strlen(str); + str += sprintf(str, "\n"); + + return str - buf; +} + +static ssize_t +efivar_attr_read(struct efivar_entry *entry, char *buf) +{ + struct efi_variable *var = &entry->var; + char *str = buf; + + if (!entry || !buf) + return -EINVAL; + + var->DataSize = 1024; + if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) + return -EIO; + + if (var->Attributes & EFI_VARIABLE_NON_VOLATILE) + str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n"); + if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS) + str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n"); + if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS) + str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n"); + if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) + str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n"); + if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) + str += sprintf(str, + "EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n"); + if (var->Attributes & + EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) + str += sprintf(str, + "EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n"); + if (var->Attributes & EFI_VARIABLE_APPEND_WRITE) + str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n"); + return str - buf; +} + +static ssize_t +efivar_size_read(struct efivar_entry *entry, char *buf) +{ + struct efi_variable *var = &entry->var; + char *str = buf; + + if (!entry || !buf) + return -EINVAL; + + var->DataSize = 1024; + if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) + return -EIO; + + str += sprintf(str, "0x%lx\n", var->DataSize); + return str - buf; +} + +static ssize_t +efivar_data_read(struct efivar_entry *entry, char *buf) +{ + struct efi_variable *var = &entry->var; + + if (!entry || !buf) + return -EINVAL; + + var->DataSize = 1024; + if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) + return -EIO; + + memcpy(buf, var->Data, var->DataSize); + return var->DataSize; +} +/* + * We allow each variable to be edited via rewriting the + * entire efi variable structure. + */ +static ssize_t +efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) +{ + struct efi_variable *new_var, *var = &entry->var; + int err; + + if (count != sizeof(struct efi_variable)) + return -EINVAL; + + new_var = (struct efi_variable *)buf; + /* + * If only updating the variable data, then the name + * and guid should remain the same + */ + if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) || + efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) { + printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n"); + return -EINVAL; + } + + if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){ + printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n"); + return -EINVAL; + } + + if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || + efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { + printk(KERN_ERR "efivars: Malformed variable content\n"); + return -EINVAL; + } + + memcpy(&entry->var, new_var, count); + + err = efivar_entry_set(entry, new_var->Attributes, + new_var->DataSize, new_var->Data, false); + if (err) { + printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err); + return -EIO; + } + + return count; +} + +static ssize_t +efivar_show_raw(struct efivar_entry *entry, char *buf) +{ + struct efi_variable *var = &entry->var; + + if (!entry || !buf) + return 0; + + var->DataSize = 1024; + if (efivar_entry_get(entry, &entry->var.Attributes, + &entry->var.DataSize, entry->var.Data)) + return -EIO; + + memcpy(buf, var, sizeof(*var)); + + return sizeof(*var); +} + +/* + * Generic read/write functions that call the specific functions of + * the attributes... + */ +static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + struct efivar_entry *var = to_efivar_entry(kobj); + struct efivar_attribute *efivar_attr = to_efivar_attr(attr); + ssize_t ret = -EIO; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + if (efivar_attr->show) { + ret = efivar_attr->show(var, buf); + } + return ret; +} + +static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + struct efivar_entry *var = to_efivar_entry(kobj); + struct efivar_attribute *efivar_attr = to_efivar_attr(attr); + ssize_t ret = -EIO; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + if (efivar_attr->store) + ret = efivar_attr->store(var, buf, count); + + return ret; +} + +static const struct sysfs_ops efivar_attr_ops = { + .show = efivar_attr_show, + .store = efivar_attr_store, +}; + +static void efivar_release(struct kobject *kobj) +{ + struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj); + kfree(var); +} + +static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL); +static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL); +static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL); +static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL); +static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw); + +static struct attribute *def_attrs[] = { + &efivar_attr_guid.attr, + &efivar_attr_size.attr, + &efivar_attr_attributes.attr, + &efivar_attr_data.attr, + &efivar_attr_raw_var.attr, + NULL, +}; + +static struct kobj_type efivar_ktype = { + .release = efivar_release, + .sysfs_ops = &efivar_attr_ops, + .default_attrs = def_attrs, +}; + +static ssize_t efivar_create(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + struct efi_variable *new_var = (struct efi_variable *)buf; + struct efivar_entry *new_entry; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || + efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { + printk(KERN_ERR "efivars: Malformed variable content\n"); + return -EINVAL; + } + + new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL); + if (!new_entry) + return -ENOMEM; + + memcpy(&new_entry->var, new_var, sizeof(*new_var)); + + err = efivar_entry_set(new_entry, new_var->Attributes, new_var->DataSize, + new_var->Data, &efivar_sysfs_list); + if (err) { + if (err == -EEXIST) + err = -EINVAL; + goto out; + } + + if (efivar_create_sysfs_entry(new_entry)) { + printk(KERN_WARNING "efivars: failed to create sysfs entry.\n"); + kfree(new_entry); + } + return count; + +out: + kfree(new_entry); + return err; +} + +static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + struct efi_variable *del_var = (struct efi_variable *)buf; + struct efivar_entry *entry; + int err = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + efivar_entry_iter_begin(); + entry = efivar_entry_find(del_var->VariableName, del_var->VendorGuid, + &efivar_sysfs_list, true); + if (!entry) + err = -EINVAL; + else if (__efivar_entry_delete(entry)) + err = -EIO; + + efivar_entry_iter_end(); + + if (err) + return err; + + efivar_unregister(entry); + + /* It's dead Jim.... */ + return count; +} + +/** + * efivar_create_sysfs_entry - create a new entry in sysfs + * @new_var: efivar entry to create + * + * Returns 1 on failure, 0 on success + */ +static int +efivar_create_sysfs_entry(struct efivar_entry *new_var) +{ + int i, short_name_size; + char *short_name; + unsigned long variable_name_size; + efi_char16_t *variable_name; + + variable_name = new_var->var.VariableName; + variable_name_size = ucs2_strlen(variable_name) * sizeof(efi_char16_t); + + /* + * Length of the variable bytes in ASCII, plus the '-' separator, + * plus the GUID, plus trailing NUL + */ + short_name_size = variable_name_size / sizeof(efi_char16_t) + + 1 + EFI_VARIABLE_GUID_LEN + 1; + + short_name = kzalloc(short_name_size, GFP_KERNEL); + + if (!short_name) + return 1; + + /* Convert Unicode to normal chars (assume top bits are 0), + ala UTF-8 */ + for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) { + short_name[i] = variable_name[i] & 0xFF; + } + /* This is ugly, but necessary to separate one vendor's + private variables from another's. */ + + *(short_name + strlen(short_name)) = '-'; + efi_guid_unparse(&new_var->var.VendorGuid, + short_name + strlen(short_name)); + + new_var->kobj.kset = efivars_kset; + + i = kobject_init_and_add(&new_var->kobj, &efivar_ktype, + NULL, "%s", short_name); + kfree(short_name); + if (i) + return 1; + + kobject_uevent(&new_var->kobj, KOBJ_ADD); + efivar_entry_add(new_var, &efivar_sysfs_list); + + return 0; +} + +static int +create_efivars_bin_attributes(void) +{ + struct bin_attribute *attr; + int error; + + /* new_var */ + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) + return -ENOMEM; + + attr->attr.name = "new_var"; + attr->attr.mode = 0200; + attr->write = efivar_create; + efivars_new_var = attr; + + /* del_var */ + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) { + error = -ENOMEM; + goto out_free; + } + attr->attr.name = "del_var"; + attr->attr.mode = 0200; + attr->write = efivar_delete; + efivars_del_var = attr; + + sysfs_bin_attr_init(efivars_new_var); + sysfs_bin_attr_init(efivars_del_var); + + /* Register */ + error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_new_var); + if (error) { + printk(KERN_ERR "efivars: unable to create new_var sysfs file" + " due to error %d\n", error); + goto out_free; + } + + error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_del_var); + if (error) { + printk(KERN_ERR "efivars: unable to create del_var sysfs file" + " due to error %d\n", error); + sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var); + goto out_free; + } + + return 0; +out_free: + kfree(efivars_del_var); + efivars_del_var = NULL; + kfree(efivars_new_var); + efivars_new_var = NULL; + return error; +} + +static int efivar_update_sysfs_entry(efi_char16_t *name, efi_guid_t vendor, + unsigned long name_size, void *data) +{ + struct efivar_entry *entry = data; + + if (efivar_entry_find(name, vendor, &efivar_sysfs_list, false)) + return 0; + + memcpy(entry->var.VariableName, name, name_size); + memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); + + return 1; +} + +static void efivar_update_sysfs_entries(struct work_struct *work) +{ + struct efivar_entry *entry; + int err; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return; + + /* Add new sysfs entries */ + while (1) { + memset(entry, 0, sizeof(*entry)); + + err = efivar_init(efivar_update_sysfs_entry, entry, + true, false, &efivar_sysfs_list); + if (!err) + break; + + efivar_create_sysfs_entry(entry); + } + + kfree(entry); +} + +static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor, + unsigned long name_size, void *data) +{ + struct efivar_entry *entry; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + memcpy(entry->var.VariableName, name, name_size); + memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); + + efivar_create_sysfs_entry(entry); + + return 0; +} + +static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data) +{ + efivar_entry_remove(entry); + efivar_unregister(entry); + return 0; +} + +void efivars_sysfs_exit(void) +{ + /* Remove all entries and destroy */ + __efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL, NULL); + + if (efivars_new_var) + sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var); + if (efivars_del_var) + sysfs_remove_bin_file(&efivars_kset->kobj, efivars_del_var); + kfree(efivars_new_var); + kfree(efivars_del_var); + kset_unregister(efivars_kset); +} + +int efivars_sysfs_init(void) +{ + struct kobject *parent_kobj = efivars_kobject(); + int error = 0; + + /* No efivars has been registered yet */ + if (!parent_kobj) + return 0; + + printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, + EFIVARS_DATE); + + efivars_kset = kset_create_and_add("vars", NULL, parent_kobj); + if (!efivars_kset) { + printk(KERN_ERR "efivars: Subsystem registration failed.\n"); + return -ENOMEM; + } + + efivar_init(efivars_sysfs_callback, NULL, false, + true, &efivar_sysfs_list); + + error = create_efivars_bin_attributes(); + if (error) { + efivars_sysfs_exit(); + return error; + } + + INIT_WORK(&efivar_work, efivar_update_sysfs_entries); + + return 0; +} +EXPORT_SYMBOL_GPL(efivars_sysfs_init); + +module_init(efivars_sysfs_init); +module_exit(efivars_sysfs_exit); diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c new file mode 100644 index 00000000000..391c67b182d --- /dev/null +++ b/drivers/firmware/efi/vars.c @@ -0,0 +1,1041 @@ +/* + * Originally from efivars.c + * + * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> + * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/capability.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/string.h> +#include <linux/smp.h> +#include <linux/efi.h> +#include <linux/sysfs.h> +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/ctype.h> +#include <linux/ucs2_string.h> + +/* Private pointer to registered efivars */ +static struct efivars *__efivars; + +static bool efivar_wq_enabled = true; +DECLARE_WORK(efivar_work, NULL); +EXPORT_SYMBOL_GPL(efivar_work); + +static bool +validate_device_path(struct efi_variable *var, int match, u8 *buffer, + unsigned long len) +{ + struct efi_generic_dev_path *node; + int offset = 0; + + node = (struct efi_generic_dev_path *)buffer; + + if (len < sizeof(*node)) + return false; + + while (offset <= len - sizeof(*node) && + node->length >= sizeof(*node) && + node->length <= len - offset) { + offset += node->length; + + if ((node->type == EFI_DEV_END_PATH || + node->type == EFI_DEV_END_PATH2) && + node->sub_type == EFI_DEV_END_ENTIRE) + return true; + + node = (struct efi_generic_dev_path *)(buffer + offset); + } + + /* + * If we're here then either node->length pointed past the end + * of the buffer or we reached the end of the buffer without + * finding a device path end node. + */ + return false; +} + +static bool +validate_boot_order(struct efi_variable *var, int match, u8 *buffer, + unsigned long len) +{ + /* An array of 16-bit integers */ + if ((len % 2) != 0) + return false; + + return true; +} + +static bool +validate_load_option(struct efi_variable *var, int match, u8 *buffer, + unsigned long len) +{ + u16 filepathlength; + int i, desclength = 0, namelen; + + namelen = ucs2_strnlen(var->VariableName, sizeof(var->VariableName)); + + /* Either "Boot" or "Driver" followed by four digits of hex */ + for (i = match; i < match+4; i++) { + if (var->VariableName[i] > 127 || + hex_to_bin(var->VariableName[i] & 0xff) < 0) + return true; + } + + /* Reject it if there's 4 digits of hex and then further content */ + if (namelen > match + 4) + return false; + + /* A valid entry must be at least 8 bytes */ + if (len < 8) + return false; + + filepathlength = buffer[4] | buffer[5] << 8; + + /* + * There's no stored length for the description, so it has to be + * found by hand + */ + desclength = ucs2_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2; + + /* Each boot entry must have a descriptor */ + if (!desclength) + return false; + + /* + * If the sum of the length of the description, the claimed filepath + * length and the original header are greater than the length of the + * variable, it's malformed + */ + if ((desclength + filepathlength + 6) > len) + return false; + + /* + * And, finally, check the filepath + */ + return validate_device_path(var, match, buffer + desclength + 6, + filepathlength); +} + +static bool +validate_uint16(struct efi_variable *var, int match, u8 *buffer, + unsigned long len) +{ + /* A single 16-bit integer */ + if (len != 2) + return false; + + return true; +} + +static bool +validate_ascii_string(struct efi_variable *var, int match, u8 *buffer, + unsigned long len) +{ + int i; + + for (i = 0; i < len; i++) { + if (buffer[i] > 127) + return false; + + if (buffer[i] == 0) + return true; + } + + return false; +} + +struct variable_validate { + char *name; + bool (*validate)(struct efi_variable *var, int match, u8 *data, + unsigned long len); +}; + +static const struct variable_validate variable_validate[] = { + { "BootNext", validate_uint16 }, + { "BootOrder", validate_boot_order }, + { "DriverOrder", validate_boot_order }, + { "Boot*", validate_load_option }, + { "Driver*", validate_load_option }, + { "ConIn", validate_device_path }, + { "ConInDev", validate_device_path }, + { "ConOut", validate_device_path }, + { "ConOutDev", validate_device_path }, + { "ErrOut", validate_device_path }, + { "ErrOutDev", validate_device_path }, + { "Timeout", validate_uint16 }, + { "Lang", validate_ascii_string }, + { "PlatformLang", validate_ascii_string }, + { "", NULL }, +}; + +bool +efivar_validate(struct efi_variable *var, u8 *data, unsigned long len) +{ + int i; + u16 *unicode_name = var->VariableName; + + for (i = 0; variable_validate[i].validate != NULL; i++) { + const char *name = variable_validate[i].name; + int match; + + for (match = 0; ; match++) { + char c = name[match]; + u16 u = unicode_name[match]; + + /* All special variables are plain ascii */ + if (u > 127) + return true; + + /* Wildcard in the matching name means we've matched */ + if (c == '*') + return variable_validate[i].validate(var, + match, data, len); + + /* Case sensitive match */ + if (c != u) + break; + + /* Reached the end of the string while matching */ + if (!c) + return variable_validate[i].validate(var, + match, data, len); + } + } + + return true; +} +EXPORT_SYMBOL_GPL(efivar_validate); + +static efi_status_t +check_var_size(u32 attributes, unsigned long size) +{ + const struct efivar_operations *fops = __efivars->ops; + + if (!fops->query_variable_store) + return EFI_UNSUPPORTED; + + return fops->query_variable_store(attributes, size); +} + +static int efi_status_to_err(efi_status_t status) +{ + int err; + + switch (status) { + case EFI_SUCCESS: + err = 0; + break; + case EFI_INVALID_PARAMETER: + err = -EINVAL; + break; + case EFI_OUT_OF_RESOURCES: + err = -ENOSPC; + break; + case EFI_DEVICE_ERROR: + err = -EIO; + break; + case EFI_WRITE_PROTECTED: + err = -EROFS; + break; + case EFI_SECURITY_VIOLATION: + err = -EACCES; + break; + case EFI_NOT_FOUND: + err = -ENOENT; + break; + default: + err = -EINVAL; + } + + return err; +} + +static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor, + struct list_head *head) +{ + struct efivar_entry *entry, *n; + unsigned long strsize1, strsize2; + bool found = false; + + strsize1 = ucs2_strsize(variable_name, 1024); + list_for_each_entry_safe(entry, n, head, list) { + strsize2 = ucs2_strsize(entry->var.VariableName, 1024); + if (strsize1 == strsize2 && + !memcmp(variable_name, &(entry->var.VariableName), + strsize2) && + !efi_guidcmp(entry->var.VendorGuid, + *vendor)) { + found = true; + break; + } + } + return found; +} + +/* + * Returns the size of variable_name, in bytes, including the + * terminating NULL character, or variable_name_size if no NULL + * character is found among the first variable_name_size bytes. + */ +static unsigned long var_name_strnsize(efi_char16_t *variable_name, + unsigned long variable_name_size) +{ + unsigned long len; + efi_char16_t c; + + /* + * The variable name is, by definition, a NULL-terminated + * string, so make absolutely sure that variable_name_size is + * the value we expect it to be. If not, return the real size. + */ + for (len = 2; len <= variable_name_size; len += sizeof(c)) { + c = variable_name[(len / sizeof(c)) - 1]; + if (!c) + break; + } + + return min(len, variable_name_size); +} + +/* + * Print a warning when duplicate EFI variables are encountered and + * disable the sysfs workqueue since the firmware is buggy. + */ +static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid, + unsigned long len16) +{ + size_t i, len8 = len16 / sizeof(efi_char16_t); + char *s8; + + /* + * Disable the workqueue since the algorithm it uses for + * detecting new variables won't work with this buggy + * implementation of GetNextVariableName(). + */ + efivar_wq_enabled = false; + + s8 = kzalloc(len8, GFP_KERNEL); + if (!s8) + return; + + for (i = 0; i < len8; i++) + s8[i] = s16[i]; + + printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n", + s8, vendor_guid); + kfree(s8); +} + +/** + * efivar_init - build the initial list of EFI variables + * @func: callback function to invoke for every variable + * @data: function-specific data to pass to @func + * @atomic: do we need to execute the @func-loop atomically? + * @duplicates: error if we encounter duplicates on @head? + * @head: initialised head of variable list + * + * Get every EFI variable from the firmware and invoke @func. @func + * should call efivar_entry_add() to build the list of variables. + * + * Returns 0 on success, or a kernel error code on failure. + */ +int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *), + void *data, bool atomic, bool duplicates, + struct list_head *head) +{ + const struct efivar_operations *ops = __efivars->ops; + unsigned long variable_name_size = 1024; + efi_char16_t *variable_name; + efi_status_t status; + efi_guid_t vendor_guid; + int err = 0; + + variable_name = kzalloc(variable_name_size, GFP_KERNEL); + if (!variable_name) { + printk(KERN_ERR "efivars: Memory allocation failed.\n"); + return -ENOMEM; + } + + spin_lock_irq(&__efivars->lock); + + /* + * Per EFI spec, the maximum storage allocated for both + * the variable name and variable data is 1024 bytes. + */ + + do { + variable_name_size = 1024; + + status = ops->get_next_variable(&variable_name_size, + variable_name, + &vendor_guid); + switch (status) { + case EFI_SUCCESS: + if (!atomic) + spin_unlock_irq(&__efivars->lock); + + variable_name_size = var_name_strnsize(variable_name, + variable_name_size); + + /* + * Some firmware implementations return the + * same variable name on multiple calls to + * get_next_variable(). Terminate the loop + * immediately as there is no guarantee that + * we'll ever see a different variable name, + * and may end up looping here forever. + */ + if (duplicates && + variable_is_present(variable_name, &vendor_guid, head)) { + dup_variable_bug(variable_name, &vendor_guid, + variable_name_size); + if (!atomic) + spin_lock_irq(&__efivars->lock); + + status = EFI_NOT_FOUND; + break; + } + + err = func(variable_name, vendor_guid, variable_name_size, data); + if (err) + status = EFI_NOT_FOUND; + + if (!atomic) + spin_lock_irq(&__efivars->lock); + + break; + case EFI_NOT_FOUND: + break; + default: + printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n", + status); + status = EFI_NOT_FOUND; + break; + } + + } while (status != EFI_NOT_FOUND); + + spin_unlock_irq(&__efivars->lock); + + kfree(variable_name); + + return err; +} +EXPORT_SYMBOL_GPL(efivar_init); + +/** + * efivar_entry_add - add entry to variable list + * @entry: entry to add to list + * @head: list head + */ +void efivar_entry_add(struct efivar_entry *entry, struct list_head *head) +{ + spin_lock_irq(&__efivars->lock); + list_add(&entry->list, head); + spin_unlock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_add); + +/** + * efivar_entry_remove - remove entry from variable list + * @entry: entry to remove from list + */ +void efivar_entry_remove(struct efivar_entry *entry) +{ + spin_lock_irq(&__efivars->lock); + list_del(&entry->list); + spin_unlock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_remove); + +/* + * efivar_entry_list_del_unlock - remove entry from variable list + * @entry: entry to remove + * + * Remove @entry from the variable list and release the list lock. + * + * NOTE: slightly weird locking semantics here - we expect to be + * called with the efivars lock already held, and we release it before + * returning. This is because this function is usually called after + * set_variable() while the lock is still held. + */ +static void efivar_entry_list_del_unlock(struct efivar_entry *entry) +{ + WARN_ON(!spin_is_locked(&__efivars->lock)); + + list_del(&entry->list); + spin_unlock_irq(&__efivars->lock); +} + +/** + * __efivar_entry_delete - delete an EFI variable + * @entry: entry containing EFI variable to delete + * + * Delete the variable from the firmware but leave @entry on the + * variable list. + * + * This function differs from efivar_entry_delete() because it does + * not remove @entry from the variable list. Also, it is safe to be + * called from within a efivar_entry_iter_begin() and + * efivar_entry_iter_end() region, unlike efivar_entry_delete(). + * + * Returns 0 on success, or a converted EFI status code if + * set_variable() fails. + */ +int __efivar_entry_delete(struct efivar_entry *entry) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + WARN_ON(!spin_is_locked(&__efivars->lock)); + + status = ops->set_variable(entry->var.VariableName, + &entry->var.VendorGuid, + 0, 0, NULL); + + return efi_status_to_err(status); +} +EXPORT_SYMBOL_GPL(__efivar_entry_delete); + +/** + * efivar_entry_delete - delete variable and remove entry from list + * @entry: entry containing variable to delete + * + * Delete the variable from the firmware and remove @entry from the + * variable list. It is the caller's responsibility to free @entry + * once we return. + * + * Returns 0 on success, or a converted EFI status code if + * set_variable() fails. + */ +int efivar_entry_delete(struct efivar_entry *entry) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + spin_lock_irq(&__efivars->lock); + status = ops->set_variable(entry->var.VariableName, + &entry->var.VendorGuid, + 0, 0, NULL); + if (!(status == EFI_SUCCESS || status == EFI_NOT_FOUND)) { + spin_unlock_irq(&__efivars->lock); + return efi_status_to_err(status); + } + + efivar_entry_list_del_unlock(entry); + return 0; +} +EXPORT_SYMBOL_GPL(efivar_entry_delete); + +/** + * efivar_entry_set - call set_variable() + * @entry: entry containing the EFI variable to write + * @attributes: variable attributes + * @size: size of @data buffer + * @data: buffer containing variable data + * @head: head of variable list + * + * Calls set_variable() for an EFI variable. If creating a new EFI + * variable, this function is usually followed by efivar_entry_add(). + * + * Before writing the variable, the remaining EFI variable storage + * space is checked to ensure there is enough room available. + * + * If @head is not NULL a lookup is performed to determine whether + * the entry is already on the list. + * + * Returns 0 on success, -EEXIST if a lookup is performed and the entry + * already exists on the list, or a converted EFI status code if + * set_variable() fails. + */ +int efivar_entry_set(struct efivar_entry *entry, u32 attributes, + unsigned long size, void *data, struct list_head *head) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + efi_char16_t *name = entry->var.VariableName; + efi_guid_t vendor = entry->var.VendorGuid; + + spin_lock_irq(&__efivars->lock); + + if (head && efivar_entry_find(name, vendor, head, false)) { + spin_unlock_irq(&__efivars->lock); + return -EEXIST; + } + + status = check_var_size(attributes, size + ucs2_strsize(name, 1024)); + if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED) + status = ops->set_variable(name, &vendor, + attributes, size, data); + + spin_unlock_irq(&__efivars->lock); + + return efi_status_to_err(status); + +} +EXPORT_SYMBOL_GPL(efivar_entry_set); + +/** + * efivar_entry_set_safe - call set_variable() if enough space in firmware + * @name: buffer containing the variable name + * @vendor: variable vendor guid + * @attributes: variable attributes + * @block: can we block in this context? + * @size: size of @data buffer + * @data: buffer containing variable data + * + * Ensures there is enough free storage in the firmware for this variable, and + * if so, calls set_variable(). If creating a new EFI variable, this function + * is usually followed by efivar_entry_add(). + * + * Returns 0 on success, -ENOSPC if the firmware does not have enough + * space for set_variable() to succeed, or a converted EFI status code + * if set_variable() fails. + */ +int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes, + bool block, unsigned long size, void *data) +{ + const struct efivar_operations *ops = __efivars->ops; + unsigned long flags; + efi_status_t status; + + if (!ops->query_variable_store) + return -ENOSYS; + + if (!block) { + if (!spin_trylock_irqsave(&__efivars->lock, flags)) + return -EBUSY; + } else { + spin_lock_irqsave(&__efivars->lock, flags); + } + + status = check_var_size(attributes, size + ucs2_strsize(name, 1024)); + if (status != EFI_SUCCESS) { + spin_unlock_irqrestore(&__efivars->lock, flags); + return -ENOSPC; + } + + status = ops->set_variable(name, &vendor, attributes, size, data); + + spin_unlock_irqrestore(&__efivars->lock, flags); + + return efi_status_to_err(status); +} +EXPORT_SYMBOL_GPL(efivar_entry_set_safe); + +/** + * efivar_entry_find - search for an entry + * @name: the EFI variable name + * @guid: the EFI variable vendor's guid + * @head: head of the variable list + * @remove: should we remove the entry from the list? + * + * Search for an entry on the variable list that has the EFI variable + * name @name and vendor guid @guid. If an entry is found on the list + * and @remove is true, the entry is removed from the list. + * + * The caller MUST call efivar_entry_iter_begin() and + * efivar_entry_iter_end() before and after the invocation of this + * function, respectively. + * + * Returns the entry if found on the list, %NULL otherwise. + */ +struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid, + struct list_head *head, bool remove) +{ + struct efivar_entry *entry, *n; + int strsize1, strsize2; + bool found = false; + + WARN_ON(!spin_is_locked(&__efivars->lock)); + + list_for_each_entry_safe(entry, n, head, list) { + strsize1 = ucs2_strsize(name, 1024); + strsize2 = ucs2_strsize(entry->var.VariableName, 1024); + if (strsize1 == strsize2 && + !memcmp(name, &(entry->var.VariableName), strsize1) && + !efi_guidcmp(guid, entry->var.VendorGuid)) { + found = true; + break; + } + } + + if (!found) + return NULL; + + if (remove) + list_del(&entry->list); + + return entry; +} +EXPORT_SYMBOL_GPL(efivar_entry_find); + +/** + * efivar_entry_size - obtain the size of a variable + * @entry: entry for this variable + * @size: location to store the variable's size + */ +int efivar_entry_size(struct efivar_entry *entry, unsigned long *size) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + *size = 0; + + spin_lock_irq(&__efivars->lock); + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, NULL, size, NULL); + spin_unlock_irq(&__efivars->lock); + + if (status != EFI_BUFFER_TOO_SMALL) + return efi_status_to_err(status); + + return 0; +} +EXPORT_SYMBOL_GPL(efivar_entry_size); + +/** + * __efivar_entry_get - call get_variable() + * @entry: read data for this variable + * @attributes: variable attributes + * @size: size of @data buffer + * @data: buffer to store variable data + * + * The caller MUST call efivar_entry_iter_begin() and + * efivar_entry_iter_end() before and after the invocation of this + * function, respectively. + */ +int __efivar_entry_get(struct efivar_entry *entry, u32 *attributes, + unsigned long *size, void *data) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + WARN_ON(!spin_is_locked(&__efivars->lock)); + + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, + attributes, size, data); + + return efi_status_to_err(status); +} +EXPORT_SYMBOL_GPL(__efivar_entry_get); + +/** + * efivar_entry_get - call get_variable() + * @entry: read data for this variable + * @attributes: variable attributes + * @size: size of @data buffer + * @data: buffer to store variable data + */ +int efivar_entry_get(struct efivar_entry *entry, u32 *attributes, + unsigned long *size, void *data) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_status_t status; + + spin_lock_irq(&__efivars->lock); + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, + attributes, size, data); + spin_unlock_irq(&__efivars->lock); + + return efi_status_to_err(status); +} +EXPORT_SYMBOL_GPL(efivar_entry_get); + +/** + * efivar_entry_set_get_size - call set_variable() and get new size (atomic) + * @entry: entry containing variable to set and get + * @attributes: attributes of variable to be written + * @size: size of data buffer + * @data: buffer containing data to write + * @set: did the set_variable() call succeed? + * + * This is a pretty special (complex) function. See efivarfs_file_write(). + * + * Atomically call set_variable() for @entry and if the call is + * successful, return the new size of the variable from get_variable() + * in @size. The success of set_variable() is indicated by @set. + * + * Returns 0 on success, -EINVAL if the variable data is invalid, + * -ENOSPC if the firmware does not have enough available space, or a + * converted EFI status code if either of set_variable() or + * get_variable() fail. + * + * If the EFI variable does not exist when calling set_variable() + * (EFI_NOT_FOUND), @entry is removed from the variable list. + */ +int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes, + unsigned long *size, void *data, bool *set) +{ + const struct efivar_operations *ops = __efivars->ops; + efi_char16_t *name = entry->var.VariableName; + efi_guid_t *vendor = &entry->var.VendorGuid; + efi_status_t status; + int err; + + *set = false; + + if (efivar_validate(&entry->var, data, *size) == false) + return -EINVAL; + + /* + * The lock here protects the get_variable call, the conditional + * set_variable call, and removal of the variable from the efivars + * list (in the case of an authenticated delete). + */ + spin_lock_irq(&__efivars->lock); + + /* + * Ensure that the available space hasn't shrunk below the safe level + */ + status = check_var_size(attributes, *size + ucs2_strsize(name, 1024)); + if (status != EFI_SUCCESS) { + if (status != EFI_UNSUPPORTED) { + err = efi_status_to_err(status); + goto out; + } + + if (*size > 65536) { + err = -ENOSPC; + goto out; + } + } + + status = ops->set_variable(name, vendor, attributes, *size, data); + if (status != EFI_SUCCESS) { + err = efi_status_to_err(status); + goto out; + } + + *set = true; + + /* + * Writing to the variable may have caused a change in size (which + * could either be an append or an overwrite), or the variable to be + * deleted. Perform a GetVariable() so we can tell what actually + * happened. + */ + *size = 0; + status = ops->get_variable(entry->var.VariableName, + &entry->var.VendorGuid, + NULL, size, NULL); + + if (status == EFI_NOT_FOUND) + efivar_entry_list_del_unlock(entry); + else + spin_unlock_irq(&__efivars->lock); + + if (status && status != EFI_BUFFER_TOO_SMALL) + return efi_status_to_err(status); + + return 0; + +out: + spin_unlock_irq(&__efivars->lock); + return err; + +} +EXPORT_SYMBOL_GPL(efivar_entry_set_get_size); + +/** + * efivar_entry_iter_begin - begin iterating the variable list + * + * Lock the variable list to prevent entry insertion and removal until + * efivar_entry_iter_end() is called. This function is usually used in + * conjunction with __efivar_entry_iter() or efivar_entry_iter(). + */ +void efivar_entry_iter_begin(void) +{ + spin_lock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_iter_begin); + +/** + * efivar_entry_iter_end - finish iterating the variable list + * + * Unlock the variable list and allow modifications to the list again. + */ +void efivar_entry_iter_end(void) +{ + spin_unlock_irq(&__efivars->lock); +} +EXPORT_SYMBOL_GPL(efivar_entry_iter_end); + +/** + * __efivar_entry_iter - iterate over variable list + * @func: callback function + * @head: head of the variable list + * @data: function-specific data to pass to callback + * @prev: entry to begin iterating from + * + * Iterate over the list of EFI variables and call @func with every + * entry on the list. It is safe for @func to remove entries in the + * list via efivar_entry_delete(). + * + * You MUST call efivar_enter_iter_begin() before this function, and + * efivar_entry_iter_end() afterwards. + * + * It is possible to begin iteration from an arbitrary entry within + * the list by passing @prev. @prev is updated on return to point to + * the last entry passed to @func. To begin iterating from the + * beginning of the list @prev must be %NULL. + * + * The restrictions for @func are the same as documented for + * efivar_entry_iter(). + */ +int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *), + struct list_head *head, void *data, + struct efivar_entry **prev) +{ + struct efivar_entry *entry, *n; + int err = 0; + + if (!prev || !*prev) { + list_for_each_entry_safe(entry, n, head, list) { + err = func(entry, data); + if (err) + break; + } + + if (prev) + *prev = entry; + + return err; + } + + + list_for_each_entry_safe_continue((*prev), n, head, list) { + err = func(*prev, data); + if (err) + break; + } + + return err; +} +EXPORT_SYMBOL_GPL(__efivar_entry_iter); + +/** + * efivar_entry_iter - iterate over variable list + * @func: callback function + * @head: head of variable list + * @data: function-specific data to pass to callback + * + * Iterate over the list of EFI variables and call @func with every + * entry on the list. It is safe for @func to remove entries in the + * list via efivar_entry_delete() while iterating. + * + * Some notes for the callback function: + * - a non-zero return value indicates an error and terminates the loop + * - @func is called from atomic context + */ +int efivar_entry_iter(int (*func)(struct efivar_entry *, void *), + struct list_head *head, void *data) +{ + int err = 0; + + efivar_entry_iter_begin(); + err = __efivar_entry_iter(func, head, data, NULL); + efivar_entry_iter_end(); + + return err; +} +EXPORT_SYMBOL_GPL(efivar_entry_iter); + +/** + * efivars_kobject - get the kobject for the registered efivars + * + * If efivars_register() has not been called we return NULL, + * otherwise return the kobject used at registration time. + */ +struct kobject *efivars_kobject(void) +{ + if (!__efivars) + return NULL; + + return __efivars->kobject; +} +EXPORT_SYMBOL_GPL(efivars_kobject); + +/** + * efivar_run_worker - schedule the efivar worker thread + */ +void efivar_run_worker(void) +{ + if (efivar_wq_enabled) + schedule_work(&efivar_work); +} +EXPORT_SYMBOL_GPL(efivar_run_worker); + +/** + * efivars_register - register an efivars + * @efivars: efivars to register + * @ops: efivars operations + * @kobject: @efivars-specific kobject + * + * Only a single efivars can be registered at any time. + */ +int efivars_register(struct efivars *efivars, + const struct efivar_operations *ops, + struct kobject *kobject) +{ + spin_lock_init(&efivars->lock); + efivars->ops = ops; + efivars->kobject = kobject; + + __efivars = efivars; + + return 0; +} +EXPORT_SYMBOL_GPL(efivars_register); + +/** + * efivars_unregister - unregister an efivars + * @efivars: efivars to unregister + * + * The caller must have already removed every entry from the list, + * failure to do so is an error. + */ +int efivars_unregister(struct efivars *efivars) +{ + int rv; + + if (!__efivars) { + printk(KERN_ERR "efivars not registered\n"); + rv = -EINVAL; + goto out; + } + + if (__efivars != efivars) { + rv = -EINVAL; + goto out; + } + + __efivars = NULL; + + rv = 0; +out: + return rv; +} +EXPORT_SYMBOL_GPL(efivars_unregister); diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c deleted file mode 100644 index f4baa11d364..00000000000 --- a/drivers/firmware/efivars.c +++ /dev/null @@ -1,2117 +0,0 @@ -/* - * EFI Variables - efivars.c - * - * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> - * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> - * - * This code takes all variables accessible from EFI runtime and - * exports them via sysfs - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - * Changelog: - * - * 17 May 2004 - Matt Domsch <Matt_Domsch@dell.com> - * remove check for efi_enabled in exit - * add MODULE_VERSION - * - * 26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com> - * minor bug fixes - * - * 21 Apr 2004 - Matt Tolentino <matthew.e.tolentino@intel.com) - * converted driver to export variable information via sysfs - * and moved to drivers/firmware directory - * bumped revision number to v0.07 to reflect conversion & move - * - * 10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com> - * fix locking per Peter Chubb's findings - * - * 25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com> - * move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_unparse() - * - * 12 Feb 2002 - Matt Domsch <Matt_Domsch@dell.com> - * use list_for_each_safe when deleting vars. - * remove ifdef CONFIG_SMP around include <linux/smp.h> - * v0.04 release to linux-ia64@linuxia64.org - * - * 20 April 2001 - Matt Domsch <Matt_Domsch@dell.com> - * Moved vars from /proc/efi to /proc/efi/vars, and made - * efi.c own the /proc/efi directory. - * v0.03 release to linux-ia64@linuxia64.org - * - * 26 March 2001 - Matt Domsch <Matt_Domsch@dell.com> - * At the request of Stephane, moved ownership of /proc/efi - * to efi.c, and now efivars lives under /proc/efi/vars. - * - * 12 March 2001 - Matt Domsch <Matt_Domsch@dell.com> - * Feedback received from Stephane Eranian incorporated. - * efivar_write() checks copy_from_user() return value. - * efivar_read/write() returns proper errno. - * v0.02 release to linux-ia64@linuxia64.org - * - * 26 February 2001 - Matt Domsch <Matt_Domsch@dell.com> - * v0.01 release to linux-ia64@linuxia64.org - */ - -#include <linux/capability.h> -#include <linux/types.h> -#include <linux/errno.h> -#include <linux/init.h> -#include <linux/mm.h> -#include <linux/module.h> -#include <linux/string.h> -#include <linux/smp.h> -#include <linux/efi.h> -#include <linux/sysfs.h> -#include <linux/kobject.h> -#include <linux/device.h> -#include <linux/slab.h> -#include <linux/pstore.h> -#include <linux/ctype.h> -#include <linux/ucs2_string.h> - -#include <linux/fs.h> -#include <linux/ramfs.h> -#include <linux/pagemap.h> - -#include <asm/uaccess.h> - -#define EFIVARS_VERSION "0.08" -#define EFIVARS_DATE "2004-May-17" - -MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>"); -MODULE_DESCRIPTION("sysfs interface to EFI Variables"); -MODULE_LICENSE("GPL"); -MODULE_VERSION(EFIVARS_VERSION); - -#define DUMP_NAME_LEN 52 - -/* - * Length of a GUID string (strlen("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee")) - * not including trailing NUL - */ -#define GUID_LEN 36 - -static bool efivars_pstore_disable = - IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE); - -module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644); - -/* - * The maximum size of VariableName + Data = 1024 - * Therefore, it's reasonable to save that much - * space in each part of the structure, - * and we use a page for reading/writing. - */ - -struct efi_variable { - efi_char16_t VariableName[1024/sizeof(efi_char16_t)]; - efi_guid_t VendorGuid; - unsigned long DataSize; - __u8 Data[1024]; - efi_status_t Status; - __u32 Attributes; -} __attribute__((packed)); - -struct efivar_entry { - struct efivars *efivars; - struct efi_variable var; - struct list_head list; - struct kobject kobj; -}; - -struct efivar_attribute { - struct attribute attr; - ssize_t (*show) (struct efivar_entry *entry, char *buf); - ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count); -}; - -static struct efivars __efivars; -static struct efivar_operations ops; - -#define PSTORE_EFI_ATTRIBUTES \ - (EFI_VARIABLE_NON_VOLATILE | \ - EFI_VARIABLE_BOOTSERVICE_ACCESS | \ - EFI_VARIABLE_RUNTIME_ACCESS) - -#define EFIVAR_ATTR(_name, _mode, _show, _store) \ -struct efivar_attribute efivar_attr_##_name = { \ - .attr = {.name = __stringify(_name), .mode = _mode}, \ - .show = _show, \ - .store = _store, \ -}; - -#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr) -#define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj) - -/* - * Prototype for sysfs creation function - */ -static int -efivar_create_sysfs_entry(struct efivars *efivars, - unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid); - -/* - * Prototype for workqueue functions updating sysfs entry - */ - -static void efivar_update_sysfs_entries(struct work_struct *); -static DECLARE_WORK(efivar_work, efivar_update_sysfs_entries); -static bool efivar_wq_enabled = true; - -static bool -validate_device_path(struct efi_variable *var, int match, u8 *buffer, - unsigned long len) -{ - struct efi_generic_dev_path *node; - int offset = 0; - - node = (struct efi_generic_dev_path *)buffer; - - if (len < sizeof(*node)) - return false; - - while (offset <= len - sizeof(*node) && - node->length >= sizeof(*node) && - node->length <= len - offset) { - offset += node->length; - - if ((node->type == EFI_DEV_END_PATH || - node->type == EFI_DEV_END_PATH2) && - node->sub_type == EFI_DEV_END_ENTIRE) - return true; - - node = (struct efi_generic_dev_path *)(buffer + offset); - } - - /* - * If we're here then either node->length pointed past the end - * of the buffer or we reached the end of the buffer without - * finding a device path end node. - */ - return false; -} - -static bool -validate_boot_order(struct efi_variable *var, int match, u8 *buffer, - unsigned long len) -{ - /* An array of 16-bit integers */ - if ((len % 2) != 0) - return false; - - return true; -} - -static bool -validate_load_option(struct efi_variable *var, int match, u8 *buffer, - unsigned long len) -{ - u16 filepathlength; - int i, desclength = 0, namelen; - - namelen = ucs2_strnlen(var->VariableName, sizeof(var->VariableName)); - - /* Either "Boot" or "Driver" followed by four digits of hex */ - for (i = match; i < match+4; i++) { - if (var->VariableName[i] > 127 || - hex_to_bin(var->VariableName[i] & 0xff) < 0) - return true; - } - - /* Reject it if there's 4 digits of hex and then further content */ - if (namelen > match + 4) - return false; - - /* A valid entry must be at least 8 bytes */ - if (len < 8) - return false; - - filepathlength = buffer[4] | buffer[5] << 8; - - /* - * There's no stored length for the description, so it has to be - * found by hand - */ - desclength = ucs2_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2; - - /* Each boot entry must have a descriptor */ - if (!desclength) - return false; - - /* - * If the sum of the length of the description, the claimed filepath - * length and the original header are greater than the length of the - * variable, it's malformed - */ - if ((desclength + filepathlength + 6) > len) - return false; - - /* - * And, finally, check the filepath - */ - return validate_device_path(var, match, buffer + desclength + 6, - filepathlength); -} - -static bool -validate_uint16(struct efi_variable *var, int match, u8 *buffer, - unsigned long len) -{ - /* A single 16-bit integer */ - if (len != 2) - return false; - - return true; -} - -static bool -validate_ascii_string(struct efi_variable *var, int match, u8 *buffer, - unsigned long len) -{ - int i; - - for (i = 0; i < len; i++) { - if (buffer[i] > 127) - return false; - - if (buffer[i] == 0) - return true; - } - - return false; -} - -struct variable_validate { - char *name; - bool (*validate)(struct efi_variable *var, int match, u8 *data, - unsigned long len); -}; - -static const struct variable_validate variable_validate[] = { - { "BootNext", validate_uint16 }, - { "BootOrder", validate_boot_order }, - { "DriverOrder", validate_boot_order }, - { "Boot*", validate_load_option }, - { "Driver*", validate_load_option }, - { "ConIn", validate_device_path }, - { "ConInDev", validate_device_path }, - { "ConOut", validate_device_path }, - { "ConOutDev", validate_device_path }, - { "ErrOut", validate_device_path }, - { "ErrOutDev", validate_device_path }, - { "Timeout", validate_uint16 }, - { "Lang", validate_ascii_string }, - { "PlatformLang", validate_ascii_string }, - { "", NULL }, -}; - -static bool -validate_var(struct efi_variable *var, u8 *data, unsigned long len) -{ - int i; - u16 *unicode_name = var->VariableName; - - for (i = 0; variable_validate[i].validate != NULL; i++) { - const char *name = variable_validate[i].name; - int match; - - for (match = 0; ; match++) { - char c = name[match]; - u16 u = unicode_name[match]; - - /* All special variables are plain ascii */ - if (u > 127) - return true; - - /* Wildcard in the matching name means we've matched */ - if (c == '*') - return variable_validate[i].validate(var, - match, data, len); - - /* Case sensitive match */ - if (c != u) - break; - - /* Reached the end of the string while matching */ - if (!c) - return variable_validate[i].validate(var, - match, data, len); - } - } - - return true; -} - -static efi_status_t -get_var_data_locked(struct efivars *efivars, struct efi_variable *var) -{ - efi_status_t status; - - var->DataSize = 1024; - status = efivars->ops->get_variable(var->VariableName, - &var->VendorGuid, - &var->Attributes, - &var->DataSize, - var->Data); - return status; -} - -static efi_status_t -get_var_data(struct efivars *efivars, struct efi_variable *var) -{ - efi_status_t status; - unsigned long flags; - - spin_lock_irqsave(&efivars->lock, flags); - status = get_var_data_locked(efivars, var); - spin_unlock_irqrestore(&efivars->lock, flags); - - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n", - status); - } - return status; -} - -static efi_status_t -check_var_size_locked(struct efivars *efivars, u32 attributes, - unsigned long size) -{ - const struct efivar_operations *fops = efivars->ops; - - if (!efivars->ops->query_variable_store) - return EFI_UNSUPPORTED; - - return fops->query_variable_store(attributes, size); -} - - -static efi_status_t -check_var_size(struct efivars *efivars, u32 attributes, unsigned long size) -{ - efi_status_t status; - unsigned long flags; - - spin_lock_irqsave(&efivars->lock, flags); - status = check_var_size_locked(efivars, attributes, size); - spin_unlock_irqrestore(&efivars->lock, flags); - - return status; -} - -static ssize_t -efivar_guid_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - char *str = buf; - - if (!entry || !buf) - return 0; - - efi_guid_unparse(&var->VendorGuid, str); - str += strlen(str); - str += sprintf(str, "\n"); - - return str - buf; -} - -static ssize_t -efivar_attr_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - char *str = buf; - efi_status_t status; - - if (!entry || !buf) - return -EINVAL; - - status = get_var_data(entry->efivars, var); - if (status != EFI_SUCCESS) - return -EIO; - - if (var->Attributes & EFI_VARIABLE_NON_VOLATILE) - str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n"); - if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS) - str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n"); - if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS) - str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n"); - if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) - str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n"); - if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) - str += sprintf(str, - "EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n"); - if (var->Attributes & - EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) - str += sprintf(str, - "EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n"); - if (var->Attributes & EFI_VARIABLE_APPEND_WRITE) - str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n"); - return str - buf; -} - -static ssize_t -efivar_size_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - char *str = buf; - efi_status_t status; - - if (!entry || !buf) - return -EINVAL; - - status = get_var_data(entry->efivars, var); - if (status != EFI_SUCCESS) - return -EIO; - - str += sprintf(str, "0x%lx\n", var->DataSize); - return str - buf; -} - -static ssize_t -efivar_data_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - efi_status_t status; - - if (!entry || !buf) - return -EINVAL; - - status = get_var_data(entry->efivars, var); - if (status != EFI_SUCCESS) - return -EIO; - - memcpy(buf, var->Data, var->DataSize); - return var->DataSize; -} -/* - * We allow each variable to be edited via rewriting the - * entire efi variable structure. - */ -static ssize_t -efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) -{ - struct efi_variable *new_var, *var = &entry->var; - struct efivars *efivars = entry->efivars; - efi_status_t status = EFI_NOT_FOUND; - - if (count != sizeof(struct efi_variable)) - return -EINVAL; - - new_var = (struct efi_variable *)buf; - /* - * If only updating the variable data, then the name - * and guid should remain the same - */ - if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) || - efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) { - printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n"); - return -EINVAL; - } - - if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){ - printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n"); - return -EINVAL; - } - - if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || - validate_var(new_var, new_var->Data, new_var->DataSize) == false) { - printk(KERN_ERR "efivars: Malformed variable content\n"); - return -EINVAL; - } - - spin_lock_irq(&efivars->lock); - - status = check_var_size_locked(efivars, new_var->Attributes, - new_var->DataSize + ucs2_strsize(new_var->VariableName, 1024)); - - if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED) - status = efivars->ops->set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); - - spin_unlock_irq(&efivars->lock); - - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", - status); - return -EIO; - } - - memcpy(&entry->var, new_var, count); - return count; -} - -static ssize_t -efivar_show_raw(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - efi_status_t status; - - if (!entry || !buf) - return 0; - - status = get_var_data(entry->efivars, var); - if (status != EFI_SUCCESS) - return -EIO; - - memcpy(buf, var, sizeof(*var)); - return sizeof(*var); -} - -/* - * Generic read/write functions that call the specific functions of - * the attributes... - */ -static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr, - char *buf) -{ - struct efivar_entry *var = to_efivar_entry(kobj); - struct efivar_attribute *efivar_attr = to_efivar_attr(attr); - ssize_t ret = -EIO; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if (efivar_attr->show) { - ret = efivar_attr->show(var, buf); - } - return ret; -} - -static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr, - const char *buf, size_t count) -{ - struct efivar_entry *var = to_efivar_entry(kobj); - struct efivar_attribute *efivar_attr = to_efivar_attr(attr); - ssize_t ret = -EIO; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if (efivar_attr->store) - ret = efivar_attr->store(var, buf, count); - - return ret; -} - -static const struct sysfs_ops efivar_attr_ops = { - .show = efivar_attr_show, - .store = efivar_attr_store, -}; - -static void efivar_release(struct kobject *kobj) -{ - struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj); - kfree(var); -} - -static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL); -static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL); -static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL); -static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL); -static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw); - -static struct attribute *def_attrs[] = { - &efivar_attr_guid.attr, - &efivar_attr_size.attr, - &efivar_attr_attributes.attr, - &efivar_attr_data.attr, - &efivar_attr_raw_var.attr, - NULL, -}; - -static struct kobj_type efivar_ktype = { - .release = efivar_release, - .sysfs_ops = &efivar_attr_ops, - .default_attrs = def_attrs, -}; - -static inline void -efivar_unregister(struct efivar_entry *var) -{ - kobject_put(&var->kobj); -} - -static int efivarfs_file_open(struct inode *inode, struct file *file) -{ - file->private_data = inode->i_private; - return 0; -} - -static int efi_status_to_err(efi_status_t status) -{ - int err; - - switch (status) { - case EFI_INVALID_PARAMETER: - err = -EINVAL; - break; - case EFI_OUT_OF_RESOURCES: - err = -ENOSPC; - break; - case EFI_DEVICE_ERROR: - err = -EIO; - break; - case EFI_WRITE_PROTECTED: - err = -EROFS; - break; - case EFI_SECURITY_VIOLATION: - err = -EACCES; - break; - case EFI_NOT_FOUND: - err = -EIO; - break; - default: - err = -EINVAL; - } - - return err; -} - -static ssize_t efivarfs_file_write(struct file *file, - const char __user *userbuf, size_t count, loff_t *ppos) -{ - struct efivar_entry *var = file->private_data; - struct efivars *efivars; - efi_status_t status; - void *data; - u32 attributes; - struct inode *inode = file->f_mapping->host; - unsigned long datasize = count - sizeof(attributes); - unsigned long newdatasize, varsize; - ssize_t bytes = 0; - - if (count < sizeof(attributes)) - return -EINVAL; - - if (copy_from_user(&attributes, userbuf, sizeof(attributes))) - return -EFAULT; - - if (attributes & ~(EFI_VARIABLE_MASK)) - return -EINVAL; - - efivars = var->efivars; - - /* - * Ensure that the user can't allocate arbitrarily large - * amounts of memory. Pick a default size of 64K if - * QueryVariableInfo() isn't supported by the firmware. - */ - - varsize = datasize + ucs2_strsize(var->var.VariableName, 1024); - status = check_var_size(efivars, attributes, varsize); - - if (status != EFI_SUCCESS) { - if (status != EFI_UNSUPPORTED) - return efi_status_to_err(status); - - if (datasize > 65536) - return -ENOSPC; - } - - data = kmalloc(datasize, GFP_KERNEL); - if (!data) - return -ENOMEM; - - if (copy_from_user(data, userbuf + sizeof(attributes), datasize)) { - bytes = -EFAULT; - goto out; - } - - if (validate_var(&var->var, data, datasize) == false) { - bytes = -EINVAL; - goto out; - } - - /* - * The lock here protects the get_variable call, the conditional - * set_variable call, and removal of the variable from the efivars - * list (in the case of an authenticated delete). - */ - spin_lock_irq(&efivars->lock); - - /* - * Ensure that the available space hasn't shrunk below the safe level - */ - - status = check_var_size_locked(efivars, attributes, varsize); - - if (status != EFI_SUCCESS && status != EFI_UNSUPPORTED) { - spin_unlock_irq(&efivars->lock); - kfree(data); - - return efi_status_to_err(status); - } - - status = efivars->ops->set_variable(var->var.VariableName, - &var->var.VendorGuid, - attributes, datasize, - data); - - if (status != EFI_SUCCESS) { - spin_unlock_irq(&efivars->lock); - kfree(data); - - return efi_status_to_err(status); - } - - bytes = count; - - /* - * Writing to the variable may have caused a change in size (which - * could either be an append or an overwrite), or the variable to be - * deleted. Perform a GetVariable() so we can tell what actually - * happened. - */ - newdatasize = 0; - status = efivars->ops->get_variable(var->var.VariableName, - &var->var.VendorGuid, - NULL, &newdatasize, - NULL); - - if (status == EFI_BUFFER_TOO_SMALL) { - spin_unlock_irq(&efivars->lock); - mutex_lock(&inode->i_mutex); - i_size_write(inode, newdatasize + sizeof(attributes)); - mutex_unlock(&inode->i_mutex); - - } else if (status == EFI_NOT_FOUND) { - list_del(&var->list); - spin_unlock_irq(&efivars->lock); - efivar_unregister(var); - drop_nlink(inode); - d_delete(file->f_dentry); - dput(file->f_dentry); - - } else { - spin_unlock_irq(&efivars->lock); - pr_warn("efivarfs: inconsistent EFI variable implementation? " - "status = %lx\n", status); - } - -out: - kfree(data); - - return bytes; -} - -static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf, - size_t count, loff_t *ppos) -{ - struct efivar_entry *var = file->private_data; - struct efivars *efivars = var->efivars; - efi_status_t status; - unsigned long datasize = 0; - u32 attributes; - void *data; - ssize_t size = 0; - - spin_lock_irq(&efivars->lock); - status = efivars->ops->get_variable(var->var.VariableName, - &var->var.VendorGuid, - &attributes, &datasize, NULL); - spin_unlock_irq(&efivars->lock); - - if (status != EFI_BUFFER_TOO_SMALL) - return efi_status_to_err(status); - - data = kmalloc(datasize + sizeof(attributes), GFP_KERNEL); - - if (!data) - return -ENOMEM; - - spin_lock_irq(&efivars->lock); - status = efivars->ops->get_variable(var->var.VariableName, - &var->var.VendorGuid, - &attributes, &datasize, - (data + sizeof(attributes))); - spin_unlock_irq(&efivars->lock); - - if (status != EFI_SUCCESS) { - size = efi_status_to_err(status); - goto out_free; - } - - memcpy(data, &attributes, sizeof(attributes)); - size = simple_read_from_buffer(userbuf, count, ppos, - data, datasize + sizeof(attributes)); -out_free: - kfree(data); - - return size; -} - -static void efivarfs_evict_inode(struct inode *inode) -{ - clear_inode(inode); -} - -static const struct super_operations efivarfs_ops = { - .statfs = simple_statfs, - .drop_inode = generic_delete_inode, - .evict_inode = efivarfs_evict_inode, - .show_options = generic_show_options, -}; - -static struct super_block *efivarfs_sb; - -static const struct inode_operations efivarfs_dir_inode_operations; - -static const struct file_operations efivarfs_file_operations = { - .open = efivarfs_file_open, - .read = efivarfs_file_read, - .write = efivarfs_file_write, - .llseek = no_llseek, -}; - -static struct inode *efivarfs_get_inode(struct super_block *sb, - const struct inode *dir, int mode, dev_t dev) -{ - struct inode *inode = new_inode(sb); - - if (inode) { - inode->i_ino = get_next_ino(); - inode->i_mode = mode; - inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; - switch (mode & S_IFMT) { - case S_IFREG: - inode->i_fop = &efivarfs_file_operations; - break; - case S_IFDIR: - inode->i_op = &efivarfs_dir_inode_operations; - inode->i_fop = &simple_dir_operations; - inc_nlink(inode); - break; - } - } - return inode; -} - -/* - * Return true if 'str' is a valid efivarfs filename of the form, - * - * VariableName-12345678-1234-1234-1234-1234567891bc - */ -static bool efivarfs_valid_name(const char *str, int len) -{ - static const char dashes[GUID_LEN] = { - [8] = 1, [13] = 1, [18] = 1, [23] = 1 - }; - const char *s = str + len - GUID_LEN; - int i; - - /* - * We need a GUID, plus at least one letter for the variable name, - * plus the '-' separator - */ - if (len < GUID_LEN + 2) - return false; - - /* GUID must be preceded by a '-' */ - if (*(s - 1) != '-') - return false; - - /* - * Validate that 's' is of the correct format, e.g. - * - * 12345678-1234-1234-1234-123456789abc - */ - for (i = 0; i < GUID_LEN; i++) { - if (dashes[i]) { - if (*s++ != '-') - return false; - } else { - if (!isxdigit(*s++)) - return false; - } - } - - return true; -} - -static void efivarfs_hex_to_guid(const char *str, efi_guid_t *guid) -{ - guid->b[0] = hex_to_bin(str[6]) << 4 | hex_to_bin(str[7]); - guid->b[1] = hex_to_bin(str[4]) << 4 | hex_to_bin(str[5]); - guid->b[2] = hex_to_bin(str[2]) << 4 | hex_to_bin(str[3]); - guid->b[3] = hex_to_bin(str[0]) << 4 | hex_to_bin(str[1]); - guid->b[4] = hex_to_bin(str[11]) << 4 | hex_to_bin(str[12]); - guid->b[5] = hex_to_bin(str[9]) << 4 | hex_to_bin(str[10]); - guid->b[6] = hex_to_bin(str[16]) << 4 | hex_to_bin(str[17]); - guid->b[7] = hex_to_bin(str[14]) << 4 | hex_to_bin(str[15]); - guid->b[8] = hex_to_bin(str[19]) << 4 | hex_to_bin(str[20]); - guid->b[9] = hex_to_bin(str[21]) << 4 | hex_to_bin(str[22]); - guid->b[10] = hex_to_bin(str[24]) << 4 | hex_to_bin(str[25]); - guid->b[11] = hex_to_bin(str[26]) << 4 | hex_to_bin(str[27]); - guid->b[12] = hex_to_bin(str[28]) << 4 | hex_to_bin(str[29]); - guid->b[13] = hex_to_bin(str[30]) << 4 | hex_to_bin(str[31]); - guid->b[14] = hex_to_bin(str[32]) << 4 | hex_to_bin(str[33]); - guid->b[15] = hex_to_bin(str[34]) << 4 | hex_to_bin(str[35]); -} - -static int efivarfs_create(struct inode *dir, struct dentry *dentry, - umode_t mode, bool excl) -{ - struct inode *inode; - struct efivars *efivars = &__efivars; - struct efivar_entry *var; - int namelen, i = 0, err = 0; - - if (!efivarfs_valid_name(dentry->d_name.name, dentry->d_name.len)) - return -EINVAL; - - inode = efivarfs_get_inode(dir->i_sb, dir, mode, 0); - if (!inode) - return -ENOMEM; - - var = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL); - if (!var) { - err = -ENOMEM; - goto out; - } - - /* length of the variable name itself: remove GUID and separator */ - namelen = dentry->d_name.len - GUID_LEN - 1; - - efivarfs_hex_to_guid(dentry->d_name.name + namelen + 1, - &var->var.VendorGuid); - - for (i = 0; i < namelen; i++) - var->var.VariableName[i] = dentry->d_name.name[i]; - - var->var.VariableName[i] = '\0'; - - inode->i_private = var; - var->efivars = efivars; - var->kobj.kset = efivars->kset; - - err = kobject_init_and_add(&var->kobj, &efivar_ktype, NULL, "%s", - dentry->d_name.name); - if (err) - goto out; - - kobject_uevent(&var->kobj, KOBJ_ADD); - spin_lock_irq(&efivars->lock); - list_add(&var->list, &efivars->list); - spin_unlock_irq(&efivars->lock); - d_instantiate(dentry, inode); - dget(dentry); -out: - if (err) { - kfree(var); - iput(inode); - } - return err; -} - -static int efivarfs_unlink(struct inode *dir, struct dentry *dentry) -{ - struct efivar_entry *var = dentry->d_inode->i_private; - struct efivars *efivars = var->efivars; - efi_status_t status; - - spin_lock_irq(&efivars->lock); - - status = efivars->ops->set_variable(var->var.VariableName, - &var->var.VendorGuid, - 0, 0, NULL); - - if (status == EFI_SUCCESS || status == EFI_NOT_FOUND) { - list_del(&var->list); - spin_unlock_irq(&efivars->lock); - efivar_unregister(var); - drop_nlink(dentry->d_inode); - dput(dentry); - return 0; - } - - spin_unlock_irq(&efivars->lock); - return -EINVAL; -}; - -/* - * Compare two efivarfs file names. - * - * An efivarfs filename is composed of two parts, - * - * 1. A case-sensitive variable name - * 2. A case-insensitive GUID - * - * So we need to perform a case-sensitive match on part 1 and a - * case-insensitive match on part 2. - */ -static int efivarfs_d_compare(const struct dentry *parent, const struct inode *pinode, - const struct dentry *dentry, const struct inode *inode, - unsigned int len, const char *str, - const struct qstr *name) -{ - int guid = len - GUID_LEN; - - if (name->len != len) - return 1; - - /* Case-sensitive compare for the variable name */ - if (memcmp(str, name->name, guid)) - return 1; - - /* Case-insensitive compare for the GUID */ - return strncasecmp(name->name + guid, str + guid, GUID_LEN); -} - -static int efivarfs_d_hash(const struct dentry *dentry, - const struct inode *inode, struct qstr *qstr) -{ - unsigned long hash = init_name_hash(); - const unsigned char *s = qstr->name; - unsigned int len = qstr->len; - - if (!efivarfs_valid_name(s, len)) - return -EINVAL; - - while (len-- > GUID_LEN) - hash = partial_name_hash(*s++, hash); - - /* GUID is case-insensitive. */ - while (len--) - hash = partial_name_hash(tolower(*s++), hash); - - qstr->hash = end_name_hash(hash); - return 0; -} - -/* - * Retaining negative dentries for an in-memory filesystem just wastes - * memory and lookup time: arrange for them to be deleted immediately. - */ -static int efivarfs_delete_dentry(const struct dentry *dentry) -{ - return 1; -} - -static struct dentry_operations efivarfs_d_ops = { - .d_compare = efivarfs_d_compare, - .d_hash = efivarfs_d_hash, - .d_delete = efivarfs_delete_dentry, -}; - -static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name) -{ - struct dentry *d; - struct qstr q; - int err; - - q.name = name; - q.len = strlen(name); - - err = efivarfs_d_hash(NULL, NULL, &q); - if (err) - return ERR_PTR(err); - - d = d_alloc(parent, &q); - if (d) - return d; - - return ERR_PTR(-ENOMEM); -} - -static int efivarfs_fill_super(struct super_block *sb, void *data, int silent) -{ - struct inode *inode = NULL; - struct dentry *root; - struct efivar_entry *entry, *n; - struct efivars *efivars = &__efivars; - char *name; - int err = -ENOMEM; - - efivarfs_sb = sb; - - sb->s_maxbytes = MAX_LFS_FILESIZE; - sb->s_blocksize = PAGE_CACHE_SIZE; - sb->s_blocksize_bits = PAGE_CACHE_SHIFT; - sb->s_magic = EFIVARFS_MAGIC; - sb->s_op = &efivarfs_ops; - sb->s_d_op = &efivarfs_d_ops; - sb->s_time_gran = 1; - - inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0); - if (!inode) - return -ENOMEM; - inode->i_op = &efivarfs_dir_inode_operations; - - root = d_make_root(inode); - sb->s_root = root; - if (!root) - return -ENOMEM; - - list_for_each_entry_safe(entry, n, &efivars->list, list) { - struct dentry *dentry, *root = efivarfs_sb->s_root; - unsigned long size = 0; - int len, i; - - inode = NULL; - - len = ucs2_strlen(entry->var.VariableName); - - /* name, plus '-', plus GUID, plus NUL*/ - name = kmalloc(len + 1 + GUID_LEN + 1, GFP_ATOMIC); - if (!name) - goto fail; - - for (i = 0; i < len; i++) - name[i] = entry->var.VariableName[i] & 0xFF; - - name[len] = '-'; - - efi_guid_unparse(&entry->var.VendorGuid, name + len + 1); - - name[len+GUID_LEN+1] = '\0'; - - inode = efivarfs_get_inode(efivarfs_sb, root->d_inode, - S_IFREG | 0644, 0); - if (!inode) - goto fail_name; - - dentry = efivarfs_alloc_dentry(root, name); - if (IS_ERR(dentry)) { - err = PTR_ERR(dentry); - goto fail_inode; - } - - /* copied by the above to local storage in the dentry. */ - kfree(name); - - spin_lock_irq(&efivars->lock); - efivars->ops->get_variable(entry->var.VariableName, - &entry->var.VendorGuid, - &entry->var.Attributes, - &size, - NULL); - spin_unlock_irq(&efivars->lock); - - mutex_lock(&inode->i_mutex); - inode->i_private = entry; - i_size_write(inode, size + sizeof(entry->var.Attributes)); - mutex_unlock(&inode->i_mutex); - d_add(dentry, inode); - } - - return 0; - -fail_inode: - iput(inode); -fail_name: - kfree(name); -fail: - return err; -} - -static struct dentry *efivarfs_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data) -{ - return mount_single(fs_type, flags, data, efivarfs_fill_super); -} - -static void efivarfs_kill_sb(struct super_block *sb) -{ - kill_litter_super(sb); - efivarfs_sb = NULL; -} - -static struct file_system_type efivarfs_type = { - .name = "efivarfs", - .mount = efivarfs_mount, - .kill_sb = efivarfs_kill_sb, -}; -MODULE_ALIAS_FS("efivarfs"); - -/* - * Handle negative dentry. - */ -static struct dentry *efivarfs_lookup(struct inode *dir, struct dentry *dentry, - unsigned int flags) -{ - if (dentry->d_name.len > NAME_MAX) - return ERR_PTR(-ENAMETOOLONG); - d_add(dentry, NULL); - return NULL; -} - -static const struct inode_operations efivarfs_dir_inode_operations = { - .lookup = efivarfs_lookup, - .unlink = efivarfs_unlink, - .create = efivarfs_create, -}; - -#ifdef CONFIG_EFI_VARS_PSTORE - -static int efi_pstore_open(struct pstore_info *psi) -{ - struct efivars *efivars = psi->data; - - spin_lock_irq(&efivars->lock); - efivars->walk_entry = list_first_entry(&efivars->list, - struct efivar_entry, list); - return 0; -} - -static int efi_pstore_close(struct pstore_info *psi) -{ - struct efivars *efivars = psi->data; - - spin_unlock_irq(&efivars->lock); - return 0; -} - -static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, - int *count, struct timespec *timespec, - char **buf, struct pstore_info *psi) -{ - efi_guid_t vendor = LINUX_EFI_CRASH_GUID; - struct efivars *efivars = psi->data; - char name[DUMP_NAME_LEN]; - int i; - int cnt; - unsigned int part, size; - unsigned long time; - - while (&efivars->walk_entry->list != &efivars->list) { - if (!efi_guidcmp(efivars->walk_entry->var.VendorGuid, - vendor)) { - for (i = 0; i < DUMP_NAME_LEN; i++) { - name[i] = efivars->walk_entry->var.VariableName[i]; - } - if (sscanf(name, "dump-type%u-%u-%d-%lu", - type, &part, &cnt, &time) == 4) { - *id = part; - *count = cnt; - timespec->tv_sec = time; - timespec->tv_nsec = 0; - } else if (sscanf(name, "dump-type%u-%u-%lu", - type, &part, &time) == 3) { - /* - * Check if an old format, - * which doesn't support holding - * multiple logs, remains. - */ - *id = part; - *count = 0; - timespec->tv_sec = time; - timespec->tv_nsec = 0; - } else { - efivars->walk_entry = list_entry( - efivars->walk_entry->list.next, - struct efivar_entry, list); - continue; - } - - get_var_data_locked(efivars, &efivars->walk_entry->var); - size = efivars->walk_entry->var.DataSize; - *buf = kmalloc(size, GFP_KERNEL); - if (*buf == NULL) - return -ENOMEM; - memcpy(*buf, efivars->walk_entry->var.Data, - size); - efivars->walk_entry = list_entry( - efivars->walk_entry->list.next, - struct efivar_entry, list); - return size; - } - efivars->walk_entry = list_entry(efivars->walk_entry->list.next, - struct efivar_entry, list); - } - return 0; -} - -static int efi_pstore_write(enum pstore_type_id type, - enum kmsg_dump_reason reason, u64 *id, - unsigned int part, int count, size_t size, - struct pstore_info *psi) -{ - char name[DUMP_NAME_LEN]; - efi_char16_t efi_name[DUMP_NAME_LEN]; - efi_guid_t vendor = LINUX_EFI_CRASH_GUID; - struct efivars *efivars = psi->data; - int i, ret = 0; - efi_status_t status = EFI_NOT_FOUND; - unsigned long flags; - - if (pstore_cannot_block_path(reason)) { - /* - * If the lock is taken by another cpu in non-blocking path, - * this driver returns without entering firmware to avoid - * hanging up. - */ - if (!spin_trylock_irqsave(&efivars->lock, flags)) - return -EBUSY; - } else - spin_lock_irqsave(&efivars->lock, flags); - - /* - * Check if there is a space enough to log. - * size: a size of logging data - * DUMP_NAME_LEN * 2: a maximum size of variable name - */ - - status = check_var_size_locked(efivars, PSTORE_EFI_ATTRIBUTES, - size + DUMP_NAME_LEN * 2); - - if (status) { - spin_unlock_irqrestore(&efivars->lock, flags); - *id = part; - return -ENOSPC; - } - - sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count, - get_seconds()); - - for (i = 0; i < DUMP_NAME_LEN; i++) - efi_name[i] = name[i]; - - efivars->ops->set_variable(efi_name, &vendor, PSTORE_EFI_ATTRIBUTES, - size, psi->buf); - - spin_unlock_irqrestore(&efivars->lock, flags); - - if (reason == KMSG_DUMP_OOPS && efivar_wq_enabled) - schedule_work(&efivar_work); - - *id = part; - return ret; -}; - -static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, - struct timespec time, struct pstore_info *psi) -{ - char name[DUMP_NAME_LEN]; - efi_char16_t efi_name[DUMP_NAME_LEN]; - char name_old[DUMP_NAME_LEN]; - efi_char16_t efi_name_old[DUMP_NAME_LEN]; - efi_guid_t vendor = LINUX_EFI_CRASH_GUID; - struct efivars *efivars = psi->data; - struct efivar_entry *entry, *found = NULL; - int i; - - sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count, - time.tv_sec); - - spin_lock_irq(&efivars->lock); - - for (i = 0; i < DUMP_NAME_LEN; i++) - efi_name[i] = name[i]; - - /* - * Clean up an entry with the same name - */ - - list_for_each_entry(entry, &efivars->list, list) { - get_var_data_locked(efivars, &entry->var); - - if (efi_guidcmp(entry->var.VendorGuid, vendor)) - continue; - if (ucs2_strncmp(entry->var.VariableName, efi_name, - ucs2_strlen(efi_name))) { - /* - * Check if an old format, - * which doesn't support holding - * multiple logs, remains. - */ - sprintf(name_old, "dump-type%u-%u-%lu", type, - (unsigned int)id, time.tv_sec); - - for (i = 0; i < DUMP_NAME_LEN; i++) - efi_name_old[i] = name_old[i]; - - if (ucs2_strncmp(entry->var.VariableName, efi_name_old, - ucs2_strlen(efi_name_old))) - continue; - } - - /* found */ - found = entry; - efivars->ops->set_variable(entry->var.VariableName, - &entry->var.VendorGuid, - PSTORE_EFI_ATTRIBUTES, - 0, NULL); - break; - } - - if (found) - list_del(&found->list); - - spin_unlock_irq(&efivars->lock); - - if (found) - efivar_unregister(found); - - return 0; -} - -static struct pstore_info efi_pstore_info = { - .owner = THIS_MODULE, - .name = "efi", - .open = efi_pstore_open, - .close = efi_pstore_close, - .read = efi_pstore_read, - .write = efi_pstore_write, - .erase = efi_pstore_erase, -}; - -static void efivar_pstore_register(struct efivars *efivars) -{ - efivars->efi_pstore_info = efi_pstore_info; - efivars->efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL); - if (efivars->efi_pstore_info.buf) { - efivars->efi_pstore_info.bufsize = 1024; - efivars->efi_pstore_info.data = efivars; - spin_lock_init(&efivars->efi_pstore_info.buf_lock); - pstore_register(&efivars->efi_pstore_info); - } -} -#else -static void efivar_pstore_register(struct efivars *efivars) -{ - return; -} -#endif - -static ssize_t efivar_create(struct file *filp, struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t pos, size_t count) -{ - struct efi_variable *new_var = (struct efi_variable *)buf; - struct efivars *efivars = bin_attr->private; - struct efivar_entry *search_efivar, *n; - unsigned long strsize1, strsize2; - efi_status_t status = EFI_NOT_FOUND; - int found = 0; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || - validate_var(new_var, new_var->Data, new_var->DataSize) == false) { - printk(KERN_ERR "efivars: Malformed variable content\n"); - return -EINVAL; - } - - spin_lock_irq(&efivars->lock); - - /* - * Does this variable already exist? - */ - list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { - strsize1 = ucs2_strsize(search_efivar->var.VariableName, 1024); - strsize2 = ucs2_strsize(new_var->VariableName, 1024); - if (strsize1 == strsize2 && - !memcmp(&(search_efivar->var.VariableName), - new_var->VariableName, strsize1) && - !efi_guidcmp(search_efivar->var.VendorGuid, - new_var->VendorGuid)) { - found = 1; - break; - } - } - if (found) { - spin_unlock_irq(&efivars->lock); - return -EINVAL; - } - - status = check_var_size_locked(efivars, new_var->Attributes, - new_var->DataSize + ucs2_strsize(new_var->VariableName, 1024)); - - if (status && status != EFI_UNSUPPORTED) { - spin_unlock_irq(&efivars->lock); - return efi_status_to_err(status); - } - - /* now *really* create the variable via EFI */ - status = efivars->ops->set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); - - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", - status); - spin_unlock_irq(&efivars->lock); - return -EIO; - } - spin_unlock_irq(&efivars->lock); - - /* Create the entry in sysfs. Locking is not required here */ - status = efivar_create_sysfs_entry(efivars, - ucs2_strsize(new_var->VariableName, - 1024), - new_var->VariableName, - &new_var->VendorGuid); - if (status) { - printk(KERN_WARNING "efivars: variable created, but sysfs entry wasn't.\n"); - } - return count; -} - -static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t pos, size_t count) -{ - struct efi_variable *del_var = (struct efi_variable *)buf; - struct efivars *efivars = bin_attr->private; - struct efivar_entry *search_efivar, *n; - unsigned long strsize1, strsize2; - efi_status_t status = EFI_NOT_FOUND; - int found = 0; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - spin_lock_irq(&efivars->lock); - - /* - * Does this variable already exist? - */ - list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { - strsize1 = ucs2_strsize(search_efivar->var.VariableName, 1024); - strsize2 = ucs2_strsize(del_var->VariableName, 1024); - if (strsize1 == strsize2 && - !memcmp(&(search_efivar->var.VariableName), - del_var->VariableName, strsize1) && - !efi_guidcmp(search_efivar->var.VendorGuid, - del_var->VendorGuid)) { - found = 1; - break; - } - } - if (!found) { - spin_unlock_irq(&efivars->lock); - return -EINVAL; - } - /* force the Attributes/DataSize to 0 to ensure deletion */ - del_var->Attributes = 0; - del_var->DataSize = 0; - - status = efivars->ops->set_variable(del_var->VariableName, - &del_var->VendorGuid, - del_var->Attributes, - del_var->DataSize, - del_var->Data); - - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", - status); - spin_unlock_irq(&efivars->lock); - return -EIO; - } - list_del(&search_efivar->list); - /* We need to release this lock before unregistering. */ - spin_unlock_irq(&efivars->lock); - efivar_unregister(search_efivar); - - /* It's dead Jim.... */ - return count; -} - -static bool variable_is_present(struct efivars *efivars, - efi_char16_t *variable_name, - efi_guid_t *vendor) -{ - struct efivar_entry *entry, *n; - unsigned long strsize1, strsize2; - bool found = false; - - strsize1 = ucs2_strsize(variable_name, 1024); - list_for_each_entry_safe(entry, n, &efivars->list, list) { - strsize2 = ucs2_strsize(entry->var.VariableName, 1024); - if (strsize1 == strsize2 && - !memcmp(variable_name, &(entry->var.VariableName), - strsize2) && - !efi_guidcmp(entry->var.VendorGuid, - *vendor)) { - found = true; - break; - } - } - return found; -} - -/* - * Returns the size of variable_name, in bytes, including the - * terminating NULL character, or variable_name_size if no NULL - * character is found among the first variable_name_size bytes. - */ -static unsigned long var_name_strnsize(efi_char16_t *variable_name, - unsigned long variable_name_size) -{ - unsigned long len; - efi_char16_t c; - - /* - * The variable name is, by definition, a NULL-terminated - * string, so make absolutely sure that variable_name_size is - * the value we expect it to be. If not, return the real size. - */ - for (len = 2; len <= variable_name_size; len += sizeof(c)) { - c = variable_name[(len / sizeof(c)) - 1]; - if (!c) - break; - } - - return min(len, variable_name_size); -} - -static void efivar_update_sysfs_entries(struct work_struct *work) -{ - struct efivars *efivars = &__efivars; - efi_guid_t vendor; - efi_char16_t *variable_name; - unsigned long variable_name_size = 1024; - efi_status_t status = EFI_NOT_FOUND; - bool found; - - /* Add new sysfs entries */ - while (1) { - variable_name = kzalloc(variable_name_size, GFP_KERNEL); - if (!variable_name) { - pr_err("efivars: Memory allocation failed.\n"); - return; - } - - spin_lock_irq(&efivars->lock); - found = false; - while (1) { - variable_name_size = 1024; - status = efivars->ops->get_next_variable( - &variable_name_size, - variable_name, - &vendor); - if (status != EFI_SUCCESS) { - break; - } else { - if (!variable_is_present(efivars, - variable_name, &vendor)) { - found = true; - break; - } - } - } - spin_unlock_irq(&efivars->lock); - - if (!found) { - kfree(variable_name); - break; - } else { - variable_name_size = var_name_strnsize(variable_name, - variable_name_size); - efivar_create_sysfs_entry(efivars, - variable_name_size, - variable_name, &vendor); - } - } -} - -/* - * Let's not leave out systab information that snuck into - * the efivars driver - */ -static ssize_t systab_show(struct kobject *kobj, - struct kobj_attribute *attr, char *buf) -{ - char *str = buf; - - if (!kobj || !buf) - return -EINVAL; - - if (efi.mps != EFI_INVALID_TABLE_ADDR) - str += sprintf(str, "MPS=0x%lx\n", efi.mps); - if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) - str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); - if (efi.acpi != EFI_INVALID_TABLE_ADDR) - str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); - if (efi.smbios != EFI_INVALID_TABLE_ADDR) - str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); - if (efi.hcdp != EFI_INVALID_TABLE_ADDR) - str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp); - if (efi.boot_info != EFI_INVALID_TABLE_ADDR) - str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info); - if (efi.uga != EFI_INVALID_TABLE_ADDR) - str += sprintf(str, "UGA=0x%lx\n", efi.uga); - - return str - buf; -} - -static struct kobj_attribute efi_attr_systab = - __ATTR(systab, 0400, systab_show, NULL); - -static struct attribute *efi_subsys_attrs[] = { - &efi_attr_systab.attr, - NULL, /* maybe more in the future? */ -}; - -static struct attribute_group efi_subsys_attr_group = { - .attrs = efi_subsys_attrs, -}; - -static struct kobject *efi_kobj; - -/* - * efivar_create_sysfs_entry() - * Requires: - * variable_name_size = number of bytes required to hold - * variable_name (not counting the NULL - * character at the end. - * efivars->lock is not held on entry or exit. - * Returns 1 on failure, 0 on success - */ -static int -efivar_create_sysfs_entry(struct efivars *efivars, - unsigned long variable_name_size, - efi_char16_t *variable_name, - efi_guid_t *vendor_guid) -{ - int i, short_name_size; - char *short_name; - struct efivar_entry *new_efivar; - - /* - * Length of the variable bytes in ASCII, plus the '-' separator, - * plus the GUID, plus trailing NUL - */ - short_name_size = variable_name_size / sizeof(efi_char16_t) - + 1 + GUID_LEN + 1; - - short_name = kzalloc(short_name_size, GFP_KERNEL); - new_efivar = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL); - - if (!short_name || !new_efivar) { - kfree(short_name); - kfree(new_efivar); - return 1; - } - - new_efivar->efivars = efivars; - memcpy(new_efivar->var.VariableName, variable_name, - variable_name_size); - memcpy(&(new_efivar->var.VendorGuid), vendor_guid, sizeof(efi_guid_t)); - - /* Convert Unicode to normal chars (assume top bits are 0), - ala UTF-8 */ - for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) { - short_name[i] = variable_name[i] & 0xFF; - } - /* This is ugly, but necessary to separate one vendor's - private variables from another's. */ - - *(short_name + strlen(short_name)) = '-'; - efi_guid_unparse(vendor_guid, short_name + strlen(short_name)); - - new_efivar->kobj.kset = efivars->kset; - i = kobject_init_and_add(&new_efivar->kobj, &efivar_ktype, NULL, - "%s", short_name); - if (i) { - kfree(short_name); - kfree(new_efivar); - return 1; - } - - kobject_uevent(&new_efivar->kobj, KOBJ_ADD); - kfree(short_name); - short_name = NULL; - - spin_lock_irq(&efivars->lock); - list_add(&new_efivar->list, &efivars->list); - spin_unlock_irq(&efivars->lock); - - return 0; -} - -static int -create_efivars_bin_attributes(struct efivars *efivars) -{ - struct bin_attribute *attr; - int error; - - /* new_var */ - attr = kzalloc(sizeof(*attr), GFP_KERNEL); - if (!attr) - return -ENOMEM; - - attr->attr.name = "new_var"; - attr->attr.mode = 0200; - attr->write = efivar_create; - attr->private = efivars; - efivars->new_var = attr; - - /* del_var */ - attr = kzalloc(sizeof(*attr), GFP_KERNEL); - if (!attr) { - error = -ENOMEM; - goto out_free; - } - attr->attr.name = "del_var"; - attr->attr.mode = 0200; - attr->write = efivar_delete; - attr->private = efivars; - efivars->del_var = attr; - - sysfs_bin_attr_init(efivars->new_var); - sysfs_bin_attr_init(efivars->del_var); - - /* Register */ - error = sysfs_create_bin_file(&efivars->kset->kobj, - efivars->new_var); - if (error) { - printk(KERN_ERR "efivars: unable to create new_var sysfs file" - " due to error %d\n", error); - goto out_free; - } - error = sysfs_create_bin_file(&efivars->kset->kobj, - efivars->del_var); - if (error) { - printk(KERN_ERR "efivars: unable to create del_var sysfs file" - " due to error %d\n", error); - sysfs_remove_bin_file(&efivars->kset->kobj, - efivars->new_var); - goto out_free; - } - - return 0; -out_free: - kfree(efivars->del_var); - efivars->del_var = NULL; - kfree(efivars->new_var); - efivars->new_var = NULL; - return error; -} - -void unregister_efivars(struct efivars *efivars) -{ - struct efivar_entry *entry, *n; - - list_for_each_entry_safe(entry, n, &efivars->list, list) { - spin_lock_irq(&efivars->lock); - list_del(&entry->list); - spin_unlock_irq(&efivars->lock); - efivar_unregister(entry); - } - if (efivars->new_var) - sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var); - if (efivars->del_var) - sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var); - kfree(efivars->new_var); - kfree(efivars->del_var); - kobject_put(efivars->kobject); - kset_unregister(efivars->kset); -} -EXPORT_SYMBOL_GPL(unregister_efivars); - -/* - * Print a warning when duplicate EFI variables are encountered and - * disable the sysfs workqueue since the firmware is buggy. - */ -static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid, - unsigned long len16) -{ - size_t i, len8 = len16 / sizeof(efi_char16_t); - char *s8; - - /* - * Disable the workqueue since the algorithm it uses for - * detecting new variables won't work with this buggy - * implementation of GetNextVariableName(). - */ - efivar_wq_enabled = false; - - s8 = kzalloc(len8, GFP_KERNEL); - if (!s8) - return; - - for (i = 0; i < len8; i++) - s8[i] = s16[i]; - - printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n", - s8, vendor_guid); - kfree(s8); -} - -int register_efivars(struct efivars *efivars, - const struct efivar_operations *ops, - struct kobject *parent_kobj) -{ - efi_status_t status = EFI_NOT_FOUND; - efi_guid_t vendor_guid; - efi_char16_t *variable_name; - unsigned long variable_name_size = 1024; - int error = 0; - - variable_name = kzalloc(variable_name_size, GFP_KERNEL); - if (!variable_name) { - printk(KERN_ERR "efivars: Memory allocation failed.\n"); - return -ENOMEM; - } - - spin_lock_init(&efivars->lock); - INIT_LIST_HEAD(&efivars->list); - efivars->ops = ops; - - efivars->kset = kset_create_and_add("vars", NULL, parent_kobj); - if (!efivars->kset) { - printk(KERN_ERR "efivars: Subsystem registration failed.\n"); - error = -ENOMEM; - goto out; - } - - efivars->kobject = kobject_create_and_add("efivars", parent_kobj); - if (!efivars->kobject) { - pr_err("efivars: Subsystem registration failed.\n"); - error = -ENOMEM; - kset_unregister(efivars->kset); - goto out; - } - - /* - * Per EFI spec, the maximum storage allocated for both - * the variable name and variable data is 1024 bytes. - */ - - do { - variable_name_size = 1024; - - status = ops->get_next_variable(&variable_name_size, - variable_name, - &vendor_guid); - switch (status) { - case EFI_SUCCESS: - variable_name_size = var_name_strnsize(variable_name, - variable_name_size); - - /* - * Some firmware implementations return the - * same variable name on multiple calls to - * get_next_variable(). Terminate the loop - * immediately as there is no guarantee that - * we'll ever see a different variable name, - * and may end up looping here forever. - */ - if (variable_is_present(efivars, variable_name, - &vendor_guid)) { - dup_variable_bug(variable_name, &vendor_guid, - variable_name_size); - status = EFI_NOT_FOUND; - break; - } - - efivar_create_sysfs_entry(efivars, - variable_name_size, - variable_name, - &vendor_guid); - break; - case EFI_NOT_FOUND: - break; - default: - printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n", - status); - status = EFI_NOT_FOUND; - break; - } - } while (status != EFI_NOT_FOUND); - - error = create_efivars_bin_attributes(efivars); - if (error) - unregister_efivars(efivars); - - if (!efivars_pstore_disable) - efivar_pstore_register(efivars); - - register_filesystem(&efivarfs_type); - -out: - kfree(variable_name); - - return error; -} -EXPORT_SYMBOL_GPL(register_efivars); - -/* - * For now we register the efi subsystem with the firmware subsystem - * and the vars subsystem with the efi subsystem. In the future, it - * might make sense to split off the efi subsystem into its own - * driver, but for now only efivars will register with it, so just - * include it here. - */ - -static int __init -efivars_init(void) -{ - int error = 0; - - printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, - EFIVARS_DATE); - - if (!efi_enabled(EFI_RUNTIME_SERVICES)) - return 0; - - /* For now we'll register the efi directory at /sys/firmware/efi */ - efi_kobj = kobject_create_and_add("efi", firmware_kobj); - if (!efi_kobj) { - printk(KERN_ERR "efivars: Firmware registration failed.\n"); - return -ENOMEM; - } - - ops.get_variable = efi.get_variable; - ops.set_variable = efi.set_variable; - ops.get_next_variable = efi.get_next_variable; - ops.query_variable_store = efi_query_variable_store; - - error = register_efivars(&__efivars, &ops, efi_kobj); - if (error) - goto err_put; - - /* Don't forget the systab entry */ - error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); - if (error) { - printk(KERN_ERR - "efivars: Sysfs attribute export failed with error %d.\n", - error); - goto err_unregister; - } - - return 0; - -err_unregister: - unregister_efivars(&__efivars); -err_put: - kobject_put(efi_kobj); - return error; -} - -static void __exit -efivars_exit(void) -{ - cancel_work_sync(&efivar_work); - - if (efi_enabled(EFI_RUNTIME_SERVICES)) { - unregister_efivars(&__efivars); - kobject_put(efi_kobj); - } -} - -module_init(efivars_init); -module_exit(efivars_exit); - diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/google/gsmi.c index 91ddf0f7a1b..acba0b9f440 100644 --- a/drivers/firmware/google/gsmi.c +++ b/drivers/firmware/google/gsmi.c @@ -28,6 +28,7 @@ #include <linux/reboot.h> #include <linux/efi.h> #include <linux/module.h> +#include <linux/ucs2_string.h> #define GSMI_SHUTDOWN_CLEAN 0 /* Clean Shutdown */ /* TODO(mikew@google.com): Tie in HARDLOCKUP_DETECTOR with NMIWDT */ @@ -288,17 +289,6 @@ static int gsmi_exec(u8 func, u8 sub) return rc; } -/* Return the number of unicode characters in data */ -static size_t -utf16_strlen(efi_char16_t *data, unsigned long maxlength) -{ - unsigned long length = 0; - - while (*data++ != 0 && length < maxlength) - length++; - return length; -} - static efi_status_t gsmi_get_variable(efi_char16_t *name, efi_guid_t *vendor, u32 *attr, unsigned long *data_size, @@ -311,7 +301,7 @@ static efi_status_t gsmi_get_variable(efi_char16_t *name, }; efi_status_t ret = EFI_SUCCESS; unsigned long flags; - size_t name_len = utf16_strlen(name, GSMI_BUF_SIZE / 2); + size_t name_len = ucs2_strnlen(name, GSMI_BUF_SIZE / 2); int rc; if (name_len >= GSMI_BUF_SIZE / 2) @@ -380,7 +370,7 @@ static efi_status_t gsmi_get_next_variable(unsigned long *name_size, return EFI_BAD_BUFFER_SIZE; /* Let's make sure the thing is at least null-terminated */ - if (utf16_strlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2) + if (ucs2_strnlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2) return EFI_INVALID_PARAMETER; spin_lock_irqsave(&gsmi_dev.lock, flags); @@ -408,7 +398,7 @@ static efi_status_t gsmi_get_next_variable(unsigned long *name_size, /* Copy the name back */ memcpy(name, gsmi_dev.name_buf->start, GSMI_BUF_SIZE); - *name_size = utf16_strlen(name, GSMI_BUF_SIZE / 2) * 2; + *name_size = ucs2_strnlen(name, GSMI_BUF_SIZE / 2) * 2; /* copy guid to return buffer */ memcpy(vendor, ¶m.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); diff --git a/fs/Kconfig b/fs/Kconfig index 780725a463b..c229f828eb0 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -211,6 +211,7 @@ source "fs/sysv/Kconfig" source "fs/ufs/Kconfig" source "fs/exofs/Kconfig" source "fs/f2fs/Kconfig" +source "fs/efivarfs/Kconfig" endif # MISC_FILESYSTEMS diff --git a/fs/Makefile b/fs/Makefile index 5e67e57b59d..f0db9c941a5 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -125,3 +125,4 @@ obj-$(CONFIG_F2FS_FS) += f2fs/ obj-y += exofs/ # Multiple modules obj-$(CONFIG_CEPH_FS) += ceph/ obj-$(CONFIG_PSTORE) += pstore/ +obj-$(CONFIG_EFIVAR_FS) += efivarfs/ diff --git a/fs/efivarfs/Kconfig b/fs/efivarfs/Kconfig new file mode 100644 index 00000000000..367bbb10c54 --- /dev/null +++ b/fs/efivarfs/Kconfig @@ -0,0 +1,12 @@ +config EFIVAR_FS + tristate "EFI Variable filesystem" + depends on EFI + help + efivarfs is a replacement filesystem for the old EFI + variable support via sysfs, as it doesn't suffer from the + same 1024-byte variable size limit. + + To compile this file system support as a module, choose M + here. The module will be called efivarfs. + + If unsure, say N. diff --git a/fs/efivarfs/Makefile b/fs/efivarfs/Makefile new file mode 100644 index 00000000000..955d478177d --- /dev/null +++ b/fs/efivarfs/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for the efivarfs filesystem +# + +obj-$(CONFIG_EFIVAR_FS) += efivarfs.o + +efivarfs-objs := inode.o file.o super.o diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c new file mode 100644 index 00000000000..ede07fc7309 --- /dev/null +++ b/fs/efivarfs/file.c @@ -0,0 +1,105 @@ +/* + * Copyright (C) 2012 Red Hat, Inc. + * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/efi.h> +#include <linux/fs.h> + +#include "internal.h" + +static ssize_t efivarfs_file_write(struct file *file, + const char __user *userbuf, size_t count, loff_t *ppos) +{ + struct efivar_entry *var = file->private_data; + void *data; + u32 attributes; + struct inode *inode = file->f_mapping->host; + unsigned long datasize = count - sizeof(attributes); + ssize_t bytes = 0; + bool set = false; + + if (count < sizeof(attributes)) + return -EINVAL; + + if (copy_from_user(&attributes, userbuf, sizeof(attributes))) + return -EFAULT; + + if (attributes & ~(EFI_VARIABLE_MASK)) + return -EINVAL; + + data = kmalloc(datasize, GFP_KERNEL); + if (!data) + return -ENOMEM; + + if (copy_from_user(data, userbuf + sizeof(attributes), datasize)) { + bytes = -EFAULT; + goto out; + } + + bytes = efivar_entry_set_get_size(var, attributes, &datasize, + data, &set); + if (!set && bytes) + goto out; + + if (bytes == -ENOENT) { + drop_nlink(inode); + d_delete(file->f_dentry); + dput(file->f_dentry); + } else { + mutex_lock(&inode->i_mutex); + i_size_write(inode, datasize + sizeof(attributes)); + mutex_unlock(&inode->i_mutex); + } + + bytes = count; + +out: + kfree(data); + + return bytes; +} + +static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct efivar_entry *var = file->private_data; + unsigned long datasize = 0; + u32 attributes; + void *data; + ssize_t size = 0; + int err; + + err = efivar_entry_size(var, &datasize); + if (err) + return err; + + data = kmalloc(datasize + sizeof(attributes), GFP_KERNEL); + + if (!data) + return -ENOMEM; + + size = efivar_entry_get(var, &attributes, &datasize, + data + sizeof(attributes)); + if (size) + goto out_free; + + memcpy(data, &attributes, sizeof(attributes)); + size = simple_read_from_buffer(userbuf, count, ppos, + data, datasize + sizeof(attributes)); +out_free: + kfree(data); + + return size; +} + +const struct file_operations efivarfs_file_operations = { + .open = simple_open, + .read = efivarfs_file_read, + .write = efivarfs_file_write, + .llseek = no_llseek, +}; diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c new file mode 100644 index 00000000000..640e289d522 --- /dev/null +++ b/fs/efivarfs/inode.c @@ -0,0 +1,173 @@ +/* + * Copyright (C) 2012 Red Hat, Inc. + * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/efi.h> +#include <linux/fs.h> +#include <linux/ctype.h> + +#include "internal.h" + +struct inode *efivarfs_get_inode(struct super_block *sb, + const struct inode *dir, int mode, dev_t dev) +{ + struct inode *inode = new_inode(sb); + + if (inode) { + inode->i_ino = get_next_ino(); + inode->i_mode = mode; + inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; + switch (mode & S_IFMT) { + case S_IFREG: + inode->i_fop = &efivarfs_file_operations; + break; + case S_IFDIR: + inode->i_op = &efivarfs_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + inc_nlink(inode); + break; + } + } + return inode; +} + +/* + * Return true if 'str' is a valid efivarfs filename of the form, + * + * VariableName-12345678-1234-1234-1234-1234567891bc + */ +bool efivarfs_valid_name(const char *str, int len) +{ + static const char dashes[EFI_VARIABLE_GUID_LEN] = { + [8] = 1, [13] = 1, [18] = 1, [23] = 1 + }; + const char *s = str + len - EFI_VARIABLE_GUID_LEN; + int i; + + /* + * We need a GUID, plus at least one letter for the variable name, + * plus the '-' separator + */ + if (len < EFI_VARIABLE_GUID_LEN + 2) + return false; + + /* GUID must be preceded by a '-' */ + if (*(s - 1) != '-') + return false; + + /* + * Validate that 's' is of the correct format, e.g. + * + * 12345678-1234-1234-1234-123456789abc + */ + for (i = 0; i < EFI_VARIABLE_GUID_LEN; i++) { + if (dashes[i]) { + if (*s++ != '-') + return false; + } else { + if (!isxdigit(*s++)) + return false; + } + } + + return true; +} + +static void efivarfs_hex_to_guid(const char *str, efi_guid_t *guid) +{ + guid->b[0] = hex_to_bin(str[6]) << 4 | hex_to_bin(str[7]); + guid->b[1] = hex_to_bin(str[4]) << 4 | hex_to_bin(str[5]); + guid->b[2] = hex_to_bin(str[2]) << 4 | hex_to_bin(str[3]); + guid->b[3] = hex_to_bin(str[0]) << 4 | hex_to_bin(str[1]); + guid->b[4] = hex_to_bin(str[11]) << 4 | hex_to_bin(str[12]); + guid->b[5] = hex_to_bin(str[9]) << 4 | hex_to_bin(str[10]); + guid->b[6] = hex_to_bin(str[16]) << 4 | hex_to_bin(str[17]); + guid->b[7] = hex_to_bin(str[14]) << 4 | hex_to_bin(str[15]); + guid->b[8] = hex_to_bin(str[19]) << 4 | hex_to_bin(str[20]); + guid->b[9] = hex_to_bin(str[21]) << 4 | hex_to_bin(str[22]); + guid->b[10] = hex_to_bin(str[24]) << 4 | hex_to_bin(str[25]); + guid->b[11] = hex_to_bin(str[26]) << 4 | hex_to_bin(str[27]); + guid->b[12] = hex_to_bin(str[28]) << 4 | hex_to_bin(str[29]); + guid->b[13] = hex_to_bin(str[30]) << 4 | hex_to_bin(str[31]); + guid->b[14] = hex_to_bin(str[32]) << 4 | hex_to_bin(str[33]); + guid->b[15] = hex_to_bin(str[34]) << 4 | hex_to_bin(str[35]); +} + +static int efivarfs_create(struct inode *dir, struct dentry *dentry, + umode_t mode, bool excl) +{ + struct inode *inode; + struct efivar_entry *var; + int namelen, i = 0, err = 0; + + if (!efivarfs_valid_name(dentry->d_name.name, dentry->d_name.len)) + return -EINVAL; + + inode = efivarfs_get_inode(dir->i_sb, dir, mode, 0); + if (!inode) + return -ENOMEM; + + var = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL); + if (!var) { + err = -ENOMEM; + goto out; + } + + /* length of the variable name itself: remove GUID and separator */ + namelen = dentry->d_name.len - EFI_VARIABLE_GUID_LEN - 1; + + efivarfs_hex_to_guid(dentry->d_name.name + namelen + 1, + &var->var.VendorGuid); + + for (i = 0; i < namelen; i++) + var->var.VariableName[i] = dentry->d_name.name[i]; + + var->var.VariableName[i] = '\0'; + + inode->i_private = var; + + efivar_entry_add(var, &efivarfs_list); + d_instantiate(dentry, inode); + dget(dentry); +out: + if (err) { + kfree(var); + iput(inode); + } + return err; +} + +static int efivarfs_unlink(struct inode *dir, struct dentry *dentry) +{ + struct efivar_entry *var = dentry->d_inode->i_private; + + if (efivar_entry_delete(var)) + return -EINVAL; + + drop_nlink(dentry->d_inode); + dput(dentry); + return 0; +}; + +/* + * Handle negative dentry. + */ +static struct dentry *efivarfs_lookup(struct inode *dir, struct dentry *dentry, + unsigned int flags) +{ + if (dentry->d_name.len > NAME_MAX) + return ERR_PTR(-ENAMETOOLONG); + d_add(dentry, NULL); + return NULL; +} + +const struct inode_operations efivarfs_dir_inode_operations = { + .lookup = efivarfs_lookup, + .unlink = efivarfs_unlink, + .create = efivarfs_create, +}; diff --git a/fs/efivarfs/internal.h b/fs/efivarfs/internal.h new file mode 100644 index 00000000000..b5ff16addb7 --- /dev/null +++ b/fs/efivarfs/internal.h @@ -0,0 +1,22 @@ +/* + * Copyright (C) 2012 Red Hat, Inc. + * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef EFIVAR_FS_INTERNAL_H +#define EFIVAR_FS_INTERNAL_H + +#include <linux/list.h> + +extern const struct file_operations efivarfs_file_operations; +extern const struct inode_operations efivarfs_dir_inode_operations; +extern bool efivarfs_valid_name(const char *str, int len); +extern struct inode *efivarfs_get_inode(struct super_block *sb, + const struct inode *dir, int mode, dev_t dev); + +extern struct list_head efivarfs_list; + +#endif /* EFIVAR_FS_INTERNAL_H */ diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c new file mode 100644 index 00000000000..525a2a1ac16 --- /dev/null +++ b/fs/efivarfs/super.c @@ -0,0 +1,268 @@ +/* + * Copyright (C) 2012 Red Hat, Inc. + * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/ctype.h> +#include <linux/efi.h> +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/pagemap.h> +#include <linux/ucs2_string.h> + +#include "internal.h" + +LIST_HEAD(efivarfs_list); + +static void efivarfs_evict_inode(struct inode *inode) +{ + clear_inode(inode); +} + +static const struct super_operations efivarfs_ops = { + .statfs = simple_statfs, + .drop_inode = generic_delete_inode, + .evict_inode = efivarfs_evict_inode, + .show_options = generic_show_options, +}; + +static struct super_block *efivarfs_sb; + +/* + * Compare two efivarfs file names. + * + * An efivarfs filename is composed of two parts, + * + * 1. A case-sensitive variable name + * 2. A case-insensitive GUID + * + * So we need to perform a case-sensitive match on part 1 and a + * case-insensitive match on part 2. + */ +static int efivarfs_d_compare(const struct dentry *parent, const struct inode *pinode, + const struct dentry *dentry, const struct inode *inode, + unsigned int len, const char *str, + const struct qstr *name) +{ + int guid = len - EFI_VARIABLE_GUID_LEN; + + if (name->len != len) + return 1; + + /* Case-sensitive compare for the variable name */ + if (memcmp(str, name->name, guid)) + return 1; + + /* Case-insensitive compare for the GUID */ + return strncasecmp(name->name + guid, str + guid, EFI_VARIABLE_GUID_LEN); +} + +static int efivarfs_d_hash(const struct dentry *dentry, + const struct inode *inode, struct qstr *qstr) +{ + unsigned long hash = init_name_hash(); + const unsigned char *s = qstr->name; + unsigned int len = qstr->len; + + if (!efivarfs_valid_name(s, len)) + return -EINVAL; + + while (len-- > EFI_VARIABLE_GUID_LEN) + hash = partial_name_hash(*s++, hash); + + /* GUID is case-insensitive. */ + while (len--) + hash = partial_name_hash(tolower(*s++), hash); + + qstr->hash = end_name_hash(hash); + return 0; +} + +/* + * Retaining negative dentries for an in-memory filesystem just wastes + * memory and lookup time: arrange for them to be deleted immediately. + */ +static int efivarfs_delete_dentry(const struct dentry *dentry) +{ + return 1; +} + +static struct dentry_operations efivarfs_d_ops = { + .d_compare = efivarfs_d_compare, + .d_hash = efivarfs_d_hash, + .d_delete = efivarfs_delete_dentry, +}; + +static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name) +{ + struct dentry *d; + struct qstr q; + int err; + + q.name = name; + q.len = strlen(name); + + err = efivarfs_d_hash(NULL, NULL, &q); + if (err) + return ERR_PTR(err); + + d = d_alloc(parent, &q); + if (d) + return d; + + return ERR_PTR(-ENOMEM); +} + +static int efivarfs_callback(efi_char16_t *name16, efi_guid_t vendor, + unsigned long name_size, void *data) +{ + struct super_block *sb = (struct super_block *)data; + struct efivar_entry *entry; + struct inode *inode = NULL; + struct dentry *dentry, *root = sb->s_root; + unsigned long size = 0; + char *name; + int len, i; + int err = -ENOMEM; + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return err; + + memcpy(entry->var.VariableName, name16, name_size); + memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); + + len = ucs2_strlen(entry->var.VariableName); + + /* name, plus '-', plus GUID, plus NUL*/ + name = kmalloc(len + 1 + EFI_VARIABLE_GUID_LEN + 1, GFP_KERNEL); + if (!name) + goto fail; + + for (i = 0; i < len; i++) + name[i] = entry->var.VariableName[i] & 0xFF; + + name[len] = '-'; + + efi_guid_unparse(&entry->var.VendorGuid, name + len + 1); + + name[len + EFI_VARIABLE_GUID_LEN+1] = '\0'; + + inode = efivarfs_get_inode(sb, root->d_inode, S_IFREG | 0644, 0); + if (!inode) + goto fail_name; + + dentry = efivarfs_alloc_dentry(root, name); + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto fail_inode; + } + + /* copied by the above to local storage in the dentry. */ + kfree(name); + + efivar_entry_size(entry, &size); + efivar_entry_add(entry, &efivarfs_list); + + mutex_lock(&inode->i_mutex); + inode->i_private = entry; + i_size_write(inode, size + sizeof(entry->var.Attributes)); + mutex_unlock(&inode->i_mutex); + d_add(dentry, inode); + + return 0; + +fail_inode: + iput(inode); +fail_name: + kfree(name); +fail: + kfree(entry); + return err; +} + +static int efivarfs_destroy(struct efivar_entry *entry, void *data) +{ + efivar_entry_remove(entry); + kfree(entry); + return 0; +} + +static int efivarfs_fill_super(struct super_block *sb, void *data, int silent) +{ + struct inode *inode = NULL; + struct dentry *root; + int err; + + efivarfs_sb = sb; + + sb->s_maxbytes = MAX_LFS_FILESIZE; + sb->s_blocksize = PAGE_CACHE_SIZE; + sb->s_blocksize_bits = PAGE_CACHE_SHIFT; + sb->s_magic = EFIVARFS_MAGIC; + sb->s_op = &efivarfs_ops; + sb->s_d_op = &efivarfs_d_ops; + sb->s_time_gran = 1; + + inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0); + if (!inode) + return -ENOMEM; + inode->i_op = &efivarfs_dir_inode_operations; + + root = d_make_root(inode); + sb->s_root = root; + if (!root) + return -ENOMEM; + + INIT_LIST_HEAD(&efivarfs_list); + + err = efivar_init(efivarfs_callback, (void *)sb, false, + true, &efivarfs_list); + if (err) + __efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL); + + return err; +} + +static struct dentry *efivarfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_single(fs_type, flags, data, efivarfs_fill_super); +} + +static void efivarfs_kill_sb(struct super_block *sb) +{ + kill_litter_super(sb); + efivarfs_sb = NULL; + + /* Remove all entries and destroy */ + __efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL); +} + +static struct file_system_type efivarfs_type = { + .name = "efivarfs", + .mount = efivarfs_mount, + .kill_sb = efivarfs_kill_sb, +}; + +static __init int efivarfs_init(void) +{ + if (!efi_enabled(EFI_RUNTIME_SERVICES)) + return 0; + + if (!efivars_kobject()) + return 0; + + return register_filesystem(&efivarfs_type); +} + +MODULE_AUTHOR("Matthew Garrett, Jeremy Kerr"); +MODULE_DESCRIPTION("EFI Variable Filesystem"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_FS("efivarfs"); + +module_init(efivarfs_init); diff --git a/include/linux/efi.h b/include/linux/efi.h index 3d7df3d32c6..2bc0ad78d05 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -670,6 +670,12 @@ static inline int efi_enabled(int facility) 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 */ #define EFI_LOCATE_ALL_HANDLES 0 @@ -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 */ |