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-rw-r--r--drivers/firmware/efivars.c2115
1 files changed, 0 insertions, 2115 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
deleted file mode 100644
index 182ce947117..00000000000
--- 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);
-