diff options
Diffstat (limited to 'drivers/firmware/efivars.c')
| -rw-r--r-- | drivers/firmware/efivars.c | 1273 |
1 files changed, 0 insertions, 1273 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c deleted file mode 100644 index d10c9873dd9..00000000000 --- a/drivers/firmware/efivars.c +++ /dev/null @@ -1,1273 +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 <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 - -/* - * 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); -}; - -#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); - -/* Return the number of unicode characters in data */ -static unsigned long -utf16_strnlen(efi_char16_t *s, size_t maxlength) -{ - unsigned long length = 0; - - while (*s++ != 0 && length < maxlength) - length++; - return length; -} - -static inline unsigned long -utf16_strlen(efi_char16_t *s) -{ - return utf16_strnlen(s, ~0UL); -} - -/* - * Return the number of bytes is the length of this string - * Note: this is NOT the same as the number of unicode characters - */ -static inline unsigned long -utf16_strsize(efi_char16_t *data, unsigned long maxlength) -{ - return utf16_strnlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t); -} - -static inline int -utf16_strncmp(const efi_char16_t *a, const efi_char16_t *b, size_t len) -{ - while (1) { - if (len == 0) - return 0; - if (*a < *b) - return -1; - if (*a > *b) - return 1; - if (*a == 0) /* implies *b == 0 */ - return 0; - a++; - b++; - len--; - } -} - -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 = utf16_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 = utf16_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; - - spin_lock(&efivars->lock); - status = get_var_data_locked(efivars, var); - spin_unlock(&efivars->lock); - - if (status != EFI_SUCCESS) { - printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n", - status); - } - 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(&efivars->lock); - status = efivars->ops->set_variable(new_var->VariableName, - &new_var->VendorGuid, - new_var->Attributes, - new_var->DataSize, - new_var->Data); - - spin_unlock(&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 struct pstore_info efi_pstore_info; - -static inline void -efivar_unregister(struct efivar_entry *var) -{ - kobject_put(&var->kobj); -} - -#ifdef CONFIG_PSTORE - -static int efi_pstore_open(struct pstore_info *psi) -{ - struct efivars *efivars = psi->data; - - spin_lock(&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(&efivars->lock); - return 0; -} - -static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, - 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; - 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-%lu", type, &part, &time) == 3) { - *id = part; - timespec->tv_sec = time; - timespec->tv_nsec = 0; - 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, size_t size, struct pstore_info *psi) -{ - char name[DUMP_NAME_LEN]; - char stub_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; - struct efivar_entry *entry, *found = NULL; - int i, ret = 0; - - sprintf(stub_name, "dump-type%u-%u-", type, part); - sprintf(name, "%s%lu", stub_name, get_seconds()); - - spin_lock(&efivars->lock); - - for (i = 0; i < DUMP_NAME_LEN; i++) - efi_name[i] = stub_name[i]; - - /* - * Clean up any entries 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 (utf16_strncmp(entry->var.VariableName, efi_name, - utf16_strlen(efi_name))) - continue; - /* Needs to be a prefix */ - if (entry->var.VariableName[utf16_strlen(efi_name)] == 0) - continue; - - /* found */ - found = entry; - efivars->ops->set_variable(entry->var.VariableName, - &entry->var.VendorGuid, - PSTORE_EFI_ATTRIBUTES, - 0, NULL); - } - - if (found) - list_del(&found->list); - - 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(&efivars->lock); - - if (found) - efivar_unregister(found); - - if (size) - ret = efivar_create_sysfs_entry(efivars, - utf16_strsize(efi_name, - DUMP_NAME_LEN * 2), - efi_name, &vendor); - - *id = part; - return ret; -}; - -static int efi_pstore_erase(enum pstore_type_id type, u64 id, - struct pstore_info *psi) -{ - efi_pstore_write(type, 0, &id, (unsigned int)id, 0, psi); - - return 0; -} -#else -static int efi_pstore_open(struct pstore_info *psi) -{ - return 0; -} - -static int efi_pstore_close(struct pstore_info *psi) -{ - return 0; -} - -static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, - struct timespec *timespec, - char **buf, struct pstore_info *psi) -{ - return -1; -} - -static int efi_pstore_write(enum pstore_type_id type, - enum kmsg_dump_reason reason, u64 *id, - unsigned int part, size_t size, struct pstore_info *psi) -{ - return 0; -} - -static int efi_pstore_erase(enum pstore_type_id type, u64 id, - struct pstore_info *psi) -{ - return 0; -} -#endif - -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 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(&efivars->lock); - - /* - * Does this variable already exist? - */ - list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { - strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024); - strsize2 = utf16_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(&efivars->lock); - return -EINVAL; - } - - /* 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(&efivars->lock); - return -EIO; - } - spin_unlock(&efivars->lock); - - /* Create the entry in sysfs. Locking is not required here */ - status = efivar_create_sysfs_entry(efivars, - utf16_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(&efivars->lock); - - /* - * Does this variable already exist? - */ - list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { - strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024); - strsize2 = utf16_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(&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(&efivars->lock); - return -EIO; - } - list_del(&search_efivar->list); - /* We need to release this lock before unregistering. */ - spin_unlock(&efivars->lock); - efivar_unregister(search_efivar); - - /* It's dead Jim.... */ - return count; -} - -/* - * 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 = variable_name_size / sizeof(efi_char16_t) + 38; - char *short_name; - struct efivar_entry *new_efivar; - - short_name = kzalloc(short_name_size + 1, 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(&efivars->lock); - list_add(&new_efivar->list, &efivars->list); - spin_unlock(&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(&efivars->lock); - list_del(&entry->list); - spin_unlock(&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); - kset_unregister(efivars->kset); -} -EXPORT_SYMBOL_GPL(unregister_efivars); - -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; - } - - /* - * 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: - 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); - - 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); - } - -out: - kfree(variable_name); - - return error; -} -EXPORT_SYMBOL_GPL(register_efivars); - -static struct efivars __efivars; -static struct efivar_operations ops; - -/* - * 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) - 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; - 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) -{ - if (efi_enabled) { - unregister_efivars(&__efivars); - kobject_put(efi_kobj); - } -} - -module_init(efivars_init); -module_exit(efivars_exit); - |
