diff options
Diffstat (limited to 'drivers/firmware/efivars.c')
| -rw-r--r-- | drivers/firmware/efivars.c | 2115 |
1 files changed, 0 insertions, 2115 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c deleted file mode 100644 index 182ce94..0000000 --- a/drivers/firmware/efivars.c +++ /dev/null @@ -1,2115 +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(efi_char16_t *variable_name, efi_guid_t *vendor) -{ - struct efivar_entry *entry, *n; - struct efivars *efivars = &__efivars; - 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(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(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); - |