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Diffstat (limited to 'kernel/drivers/firmware/efi/efivars.c')
-rw-r--r--kernel/drivers/firmware/efi/efivars.c755
1 files changed, 755 insertions, 0 deletions
diff --git a/kernel/drivers/firmware/efi/efivars.c b/kernel/drivers/firmware/efi/efivars.c
new file mode 100644
index 000000000..7b2e0496e
--- /dev/null
+++ b/kernel/drivers/firmware/efi/efivars.c
@@ -0,0 +1,755 @@
+/*
+ * 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_to_str()
+ *
+ * 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/slab.h>
+#include <linux/ucs2_string.h>
+#include <linux/compat.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);
+MODULE_ALIAS("platform:efivars");
+
+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 compat_efi_variable {
+ efi_char16_t VariableName[EFI_VAR_NAME_LEN/sizeof(efi_char16_t)];
+ efi_guid_t VendorGuid;
+ __u32 DataSize;
+ __u8 Data[1024];
+ __u32 Status;
+ __u32 Attributes;
+} __packed;
+
+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_to_str(&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;
+}
+
+static inline int
+sanity_check(struct efi_variable *var, efi_char16_t *name, efi_guid_t vendor,
+ unsigned long size, u32 attributes, u8 *data)
+{
+ /*
+ * If only updating the variable data, then the name
+ * and guid should remain the same
+ */
+ if (memcmp(name, var->VariableName, sizeof(var->VariableName)) ||
+ efi_guidcmp(vendor, var->VendorGuid)) {
+ printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n");
+ return -EINVAL;
+ }
+
+ if ((size <= 0) || (attributes == 0)){
+ printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n");
+ return -EINVAL;
+ }
+
+ if ((attributes & ~EFI_VARIABLE_MASK) != 0 ||
+ efivar_validate(name, data, size) == false) {
+ printk(KERN_ERR "efivars: Malformed variable content\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static inline bool is_compat(void)
+{
+ if (IS_ENABLED(CONFIG_COMPAT) && is_compat_task())
+ return true;
+
+ return false;
+}
+
+static void
+copy_out_compat(struct efi_variable *dst, struct compat_efi_variable *src)
+{
+ memcpy(dst->VariableName, src->VariableName, EFI_VAR_NAME_LEN);
+ memcpy(dst->Data, src->Data, sizeof(src->Data));
+
+ dst->VendorGuid = src->VendorGuid;
+ dst->DataSize = src->DataSize;
+ dst->Attributes = src->Attributes;
+}
+
+/*
+ * 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;
+ efi_char16_t *name;
+ unsigned long size;
+ efi_guid_t vendor;
+ u32 attributes;
+ u8 *data;
+ int err;
+
+ if (is_compat()) {
+ struct compat_efi_variable *compat;
+
+ if (count != sizeof(*compat))
+ return -EINVAL;
+
+ compat = (struct compat_efi_variable *)buf;
+ attributes = compat->Attributes;
+ vendor = compat->VendorGuid;
+ name = compat->VariableName;
+ size = compat->DataSize;
+ data = compat->Data;
+
+ err = sanity_check(var, name, vendor, size, attributes, data);
+ if (err)
+ return err;
+
+ copy_out_compat(&entry->var, compat);
+ } else {
+ if (count != sizeof(struct efi_variable))
+ return -EINVAL;
+
+ new_var = (struct efi_variable *)buf;
+
+ attributes = new_var->Attributes;
+ vendor = new_var->VendorGuid;
+ name = new_var->VariableName;
+ size = new_var->DataSize;
+ data = new_var->Data;
+
+ err = sanity_check(var, name, vendor, size, attributes, data);
+ if (err)
+ return err;
+
+ memcpy(&entry->var, new_var, count);
+ }
+
+ err = efivar_entry_set(entry, attributes, size, data, NULL);
+ 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;
+ struct compat_efi_variable *compat;
+ size_t size;
+
+ if (!entry || !buf)
+ return 0;
+
+ var->DataSize = 1024;
+ if (efivar_entry_get(entry, &entry->var.Attributes,
+ &entry->var.DataSize, entry->var.Data))
+ return -EIO;
+
+ if (is_compat()) {
+ compat = (struct compat_efi_variable *)buf;
+
+ size = sizeof(*compat);
+ memcpy(compat->VariableName, var->VariableName,
+ EFI_VAR_NAME_LEN);
+ memcpy(compat->Data, var->Data, sizeof(compat->Data));
+
+ compat->VendorGuid = var->VendorGuid;
+ compat->DataSize = var->DataSize;
+ compat->Attributes = var->Attributes;
+ } else {
+ size = sizeof(*var);
+ memcpy(buf, var, size);
+ }
+
+ return size;
+}
+
+/*
+ * 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 compat_efi_variable *compat = (struct compat_efi_variable *)buf;
+ struct efi_variable *new_var = (struct efi_variable *)buf;
+ struct efivar_entry *new_entry;
+ bool need_compat = is_compat();
+ efi_char16_t *name;
+ unsigned long size;
+ u32 attributes;
+ u8 *data;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (need_compat) {
+ if (count != sizeof(*compat))
+ return -EINVAL;
+
+ attributes = compat->Attributes;
+ name = compat->VariableName;
+ size = compat->DataSize;
+ data = compat->Data;
+ } else {
+ if (count != sizeof(*new_var))
+ return -EINVAL;
+
+ attributes = new_var->Attributes;
+ name = new_var->VariableName;
+ size = new_var->DataSize;
+ data = new_var->Data;
+ }
+
+ if ((attributes & ~EFI_VARIABLE_MASK) != 0 ||
+ efivar_validate(name, data, size) == false) {
+ printk(KERN_ERR "efivars: Malformed variable content\n");
+ return -EINVAL;
+ }
+
+ new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL);
+ if (!new_entry)
+ return -ENOMEM;
+
+ if (need_compat)
+ copy_out_compat(&new_entry->var, compat);
+ else
+ memcpy(&new_entry->var, new_var, sizeof(*new_var));
+
+ err = efivar_entry_set(new_entry, attributes, size,
+ 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 compat_efi_variable *compat;
+ struct efivar_entry *entry;
+ efi_char16_t *name;
+ efi_guid_t vendor;
+ int err = 0;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (is_compat()) {
+ if (count != sizeof(*compat))
+ return -EINVAL;
+
+ compat = (struct compat_efi_variable *)buf;
+ name = compat->VariableName;
+ vendor = compat->VendorGuid;
+ } else {
+ if (count != sizeof(*del_var))
+ return -EINVAL;
+
+ name = del_var->VariableName;
+ vendor = del_var->VendorGuid;
+ }
+
+ efivar_entry_iter_begin();
+ entry = efivar_entry_find(name, vendor, &efivar_sysfs_list, true);
+ if (!entry)
+ err = -EINVAL;
+ else if (__efivar_entry_delete(entry))
+ err = -EIO;
+
+ if (err) {
+ efivar_entry_iter_end();
+ return err;
+ }
+
+ if (!entry->scanning) {
+ efivar_entry_iter_end();
+ efivar_unregister(entry);
+ } else
+ efivar_entry_iter_end();
+
+ /* 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_to_str(&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;
+
+ /* Add new sysfs entries */
+ while (1) {
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return;
+
+ 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;
+}
+
+static 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;
+
+ if (!efi_enabled(EFI_RUNTIME_SERVICES))
+ return -ENODEV;
+
+ /* 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);