+++ /dev/null
-/*
- * EFI Variables - efivars.c
- *
- * Copyright (C) 2001 Dell Computer Corporation <Matt_Domsch@dell.com>
- *
- * This code takes all variables accessible from EFI runtime and
- * exports them via /proc
- *
- * Reads to /proc/efi/vars/varname return an efi_variable_t structure.
- * Writes to /proc/efi/vars/varname must be an efi_variable_t structure.
- * Writes with DataSize = 0 or Attributes = 0 deletes the variable.
- * Writes with a new value in VariableName+VendorGuid creates
- * a new variable.
- *
- *
- * 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:
- *
- * 10 Feb 2004 - Stephane Eranian <eranian@hpl.hp.com>
- * Provide FPSWA version number via /proc/efi/fpswa
- *
- * 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/config.h>
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/proc_fs.h>
-#include <linux/sched.h> /* for capable() */
-#include <linux/mm.h>
-#include <linux/module.h>
-#include <linux/smp.h>
-#include <linux/efi.h>
-
-#include <asm/fpswa.h>
-#include <asm/uaccess.h>
-
-MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
-MODULE_DESCRIPTION("/proc interface to EFI Variables");
-MODULE_LICENSE("GPL");
-
-#define EFIVARS_VERSION "0.06 2002-Dec-10"
-
-static int
-efivar_read(char *page, char **start, off_t off,
- int count, int *eof, void *data);
-static int
-efivar_write(struct file *file, const char *buffer,
- unsigned long count, void *data);
-
-
-/*
- * 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.
- */
-
-typedef struct _efi_variable_t {
- 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)) efi_variable_t;
-
-
-typedef struct _efivar_entry_t {
- efi_variable_t var;
- struct proc_dir_entry *entry;
- struct list_head list;
-} efivar_entry_t;
-
-/*
- efivars_lock protects two things:
- 1) efivar_list - adds, removals, reads, writes
- 2) efi.[gs]et_variable() calls.
- It must not be held when creating proc entries or calling kmalloc.
- efi.get_next_variable() is only called from efivars_init(),
- which is protected by the BKL, so that path is safe.
-*/
-static spinlock_t efivars_lock = SPIN_LOCK_UNLOCKED;
-static LIST_HEAD(efivar_list);
-static struct proc_dir_entry *efi_vars_dir;
-
-#define efivar_entry(n) list_entry(n, efivar_entry_t, list)
-
-/* Return the number of unicode characters in data */
-static unsigned long
-utf8_strlen(efi_char16_t *data, unsigned long maxlength)
-{
- unsigned long length = 0;
- while (*data++ != 0 && length < maxlength)
- length++;
- return length;
-}
-
-/* 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
-utf8_strsize(efi_char16_t *data, unsigned long maxlength)
-{
- return utf8_strlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t);
-}
-
-
-static int
-proc_calc_metrics(char *page, char **start, off_t off,
- int count, int *eof, int len)
-{
- if (len <= off+count) *eof = 1;
- *start = page + off;
- len -= off;
- if (len>count) len = count;
- if (len<0) len = 0;
- return len;
-}
-
-/*
- * efivar_create_proc_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_proc_entry(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;
- efivar_entry_t *new_efivar;
-
- short_name = kmalloc(short_name_size+1, GFP_KERNEL);
- new_efivar = kmalloc(sizeof(efivar_entry_t), GFP_KERNEL);
-
- if (!short_name || !new_efivar) {
- if (short_name) kfree(short_name);
- if (new_efivar) kfree(new_efivar);
- return 1;
- }
- memset(short_name, 0, short_name_size+1);
- memset(new_efivar, 0, sizeof(efivar_entry_t));
-
- 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));
-
- /* Create the entry in proc */
- new_efivar->entry = create_proc_entry(short_name, 0600, efi_vars_dir);
- kfree(short_name); short_name = NULL;
- if (!new_efivar->entry) return 1;
-
- new_efivar->entry->owner = THIS_MODULE;
- new_efivar->entry->data = new_efivar;
- new_efivar->entry->read_proc = efivar_read;
- new_efivar->entry->write_proc = efivar_write;
-
- spin_lock(&efivars_lock);
- list_add(&new_efivar->list, &efivar_list);
- spin_unlock(&efivars_lock);
-
- return 0;
-}
-
-
-
-/***********************************************************
- * efivar_read()
- * Requires:
- * Modifies: page
- * Returns: number of bytes written, or -EINVAL on failure
- ***********************************************************/
-
-static int
-efivar_read(char *page, char **start, off_t off, int count, int *eof, void *data)
-{
- int len = sizeof(efi_variable_t);
- efivar_entry_t *efi_var = data;
- efi_variable_t *var_data = (efi_variable_t *)page;
-
- if (!page || !data) return -EINVAL;
-
- spin_lock(&efivars_lock);
-
- memcpy(var_data, &efi_var->var, len);
-
- var_data->DataSize = 1024;
- var_data->Status = efi.get_variable(var_data->VariableName,
- &var_data->VendorGuid,
- &var_data->Attributes,
- &var_data->DataSize,
- var_data->Data);
-
- spin_unlock(&efivars_lock);
-
- return proc_calc_metrics(page, start, off, count, eof, len);
-}
-
-/***********************************************************
- * efivar_write()
- * Requires: data is an efi_setvariable_t data type,
- * properly filled in, possibly by a call
- * first to efivar_read().
- * Caller must have CAP_SYS_ADMIN
- * Modifies: NVRAM
- * Returns: var_data->DataSize on success, errno on failure
- *
- ***********************************************************/
-static int
-efivar_write(struct file *file, const char *buffer,
- unsigned long count, void *data)
-{
- unsigned long strsize1, strsize2;
- int found=0;
- struct list_head *pos, *n;
- unsigned long size = sizeof(efi_variable_t);
- efi_status_t status;
- efivar_entry_t *efivar = data, *search_efivar = NULL;
- efi_variable_t *var_data;
- if (!data || count != size) {
- printk(KERN_WARNING "efivars: improper struct of size 0x%lx passed.\n", count);
- return -EINVAL;
- }
- if (!capable(CAP_SYS_ADMIN))
- return -EACCES;
-
- var_data = kmalloc(size, GFP_KERNEL);
- if (!var_data)
- return -ENOMEM;
- if (copy_from_user(var_data, buffer, size)) {
- kfree(var_data);
- return -EFAULT;
- }
-
- spin_lock(&efivars_lock);
-
- /* Since the data ptr we've currently got is probably for
- a different variable find the right variable.
- This allows any properly formatted data structure to
- be written to any of the files in /proc/efi/vars and it will work.
- */
- list_for_each_safe(pos, n, &efivar_list) {
- search_efivar = efivar_entry(pos);
- strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024);
- strsize2 = utf8_strsize(var_data->VariableName, 1024);
- if ( strsize1 == strsize2 &&
- !memcmp(&(search_efivar->var.VariableName),
- var_data->VariableName, strsize1) &&
- !efi_guidcmp(search_efivar->var.VendorGuid,
- var_data->VendorGuid)) {
- found = 1;
- break;
- }
- }
- if (found) efivar = search_efivar;
-
- status = efi.set_variable(var_data->VariableName,
- &var_data->VendorGuid,
- var_data->Attributes,
- var_data->DataSize,
- var_data->Data);
-
- if (status != EFI_SUCCESS) {
- printk(KERN_WARNING "set_variable() failed: status=%lx\n", status);
- kfree(var_data);
- spin_unlock(&efivars_lock);
- return -EIO;
- }
-
-
- if (!var_data->DataSize || !var_data->Attributes) {
- /* We just deleted the NVRAM variable */
- remove_proc_entry(efivar->entry->name, efi_vars_dir);
- list_del(&efivar->list);
- kfree(efivar);
- }
-
- spin_unlock(&efivars_lock);
-
- /* If this is a new variable, set up the proc entry for it. */
- if (!found) {
- efivar_create_proc_entry(utf8_strsize(var_data->VariableName,
- 1024),
- var_data->VariableName,
- &var_data->VendorGuid);
- }
-
- kfree(var_data);
- return size;
-}
-
-/*
- * The EFI system table contains pointers to the SAL system table,
- * HCDP, ACPI, SMBIOS, etc, that may be useful to applications.
- */
-static ssize_t
-efi_systab_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
-{
- void *data;
- u8 *proc_buffer;
- ssize_t size, length;
- int ret;
- const int max_nr_entries = 7; /* num ptrs to tables we could expose */
- const int max_line_len = 80;
-
- if (!efi.systab)
- return 0;
-
- proc_buffer = kmalloc(max_nr_entries * max_line_len, GFP_KERNEL);
- if (!proc_buffer)
- return -ENOMEM;
-
- length = 0;
- if (efi.mps)
- length += sprintf(proc_buffer + length, "MPS=0x%lx\n", __pa(efi.mps));
- if (efi.acpi20)
- length += sprintf(proc_buffer + length, "ACPI20=0x%lx\n", __pa(efi.acpi20));
- if (efi.acpi)
- length += sprintf(proc_buffer + length, "ACPI=0x%lx\n", __pa(efi.acpi));
- if (efi.smbios)
- length += sprintf(proc_buffer + length, "SMBIOS=0x%lx\n", __pa(efi.smbios));
- if (efi.sal_systab)
- length += sprintf(proc_buffer + length, "SAL=0x%lx\n", __pa(efi.sal_systab));
- if (efi.hcdp)
- length += sprintf(proc_buffer + length, "HCDP=0x%lx\n", __pa(efi.hcdp));
- if (efi.boot_info)
- length += sprintf(proc_buffer + length, "BOOTINFO=0x%lx\n", __pa(efi.boot_info));
-
- if (*ppos >= length) {
- ret = 0;
- goto out;
- }
-
- data = proc_buffer + file->f_pos;
- size = length - file->f_pos;
- if (size > count)
- size = count;
- if (copy_to_user(buffer, data, size)) {
- ret = -EFAULT;
- goto out;
- }
-
- *ppos += size;
- ret = size;
-
-out:
- kfree(proc_buffer);
- return ret;
-}
-
-static struct proc_dir_entry *efi_systab_entry;
-static struct file_operations efi_systab_fops = {
- .read = efi_systab_read,
-};
-
-static ssize_t
-efi_fpswa_read (struct file *file, char *buffer, size_t count, loff_t *ppos)
-{
- ssize_t size, length;
- char str[32];
- void *data;
-
- snprintf(str, sizeof(str), "revision=%u.%u\n",
- fpswa_interface->revision >> 16, fpswa_interface->revision & 0xffff);
-
- length = strlen(str);
-
- if (*ppos >= length)
- return 0;
-
- data = str + file->f_pos;
- size = length - file->f_pos;
- if (size > count)
- size = count;
- if (copy_to_user(buffer, data, size))
- return -EFAULT;
-
- *ppos += size;
- return size;
-}
-
-static struct proc_dir_entry *efi_fpswa_entry;
-static struct file_operations efi_fpswa_fops = {
- .read = efi_fpswa_read,
-};
-
-static int __init
-efivars_init(void)
-{
- efi_status_t status;
- efi_guid_t vendor_guid;
- efi_char16_t *variable_name = kmalloc(1024, GFP_KERNEL);
- unsigned long variable_name_size = 1024;
-
- printk(KERN_INFO "EFI Variables Facility v%s\n", EFIVARS_VERSION);
-
- /* Since efi.c happens before procfs is available,
- we create the directory here if it doesn't
- already exist. There's probably a better way
- to do this.
- */
- if (!efi_dir)
- efi_dir = proc_mkdir("efi", NULL);
-
- efi_systab_entry = create_proc_entry("systab", S_IRUSR | S_IRGRP, efi_dir);
- if (efi_systab_entry)
- efi_systab_entry->proc_fops = &efi_systab_fops;
-
- if (fpswa_interface) {
- efi_fpswa_entry = create_proc_entry("fpswa", S_IRUGO, efi_dir);
- if (efi_fpswa_entry)
- efi_fpswa_entry->proc_fops = &efi_fpswa_fops;
- }
-
- efi_vars_dir = proc_mkdir("vars", efi_dir);
-
- /* Per EFI spec, the maximum storage allocated for both
- the variable name and variable data is 1024 bytes.
- */
-
- memset(variable_name, 0, 1024);
-
- do {
- variable_name_size=1024;
-
- status = efi.get_next_variable(&variable_name_size,
- variable_name,
- &vendor_guid);
-
-
- switch (status) {
- case EFI_SUCCESS:
- efivar_create_proc_entry(variable_name_size,
- variable_name,
- &vendor_guid);
- break;
- case EFI_NOT_FOUND:
- break;
- default:
- printk(KERN_WARNING "get_next_variable: status=%lx\n", status);
- status = EFI_NOT_FOUND;
- break;
- }
-
- } while (status != EFI_NOT_FOUND);
-
- kfree(variable_name);
- return 0;
-}
-
-static void __exit
-efivars_exit(void)
-{
- struct list_head *pos, *n;
- efivar_entry_t *efivar;
-
- spin_lock(&efivars_lock);
- if (efi_systab_entry)
- remove_proc_entry(efi_systab_entry->name, efi_dir);
- list_for_each_safe(pos, n, &efivar_list) {
- efivar = efivar_entry(pos);
- remove_proc_entry(efivar->entry->name, efi_vars_dir);
- list_del(&efivar->list);
- kfree(efivar);
- }
- spin_unlock(&efivars_lock);
-
- remove_proc_entry(efi_vars_dir->name, efi_dir);
-}
-
-module_init(efivars_init);
-module_exit(efivars_exit);
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only. This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-indent-level: 4
- * c-brace-imaginary-offset: 0
- * c-brace-offset: -4
- * c-argdecl-indent: 4
- * c-label-offset: -4
- * c-continued-statement-offset: 4
- * c-continued-brace-offset: 0
- * indent-tabs-mode: nil
- * tab-width: 8
- * End:
- */
projects / history.git / commitdiff