2 * EFI Variables - efivars.c
4 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
5 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
7 * This code takes all variables accessible from EFI runtime and
8 * exports them via sysfs
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 * 17 May 2004 - Matt Domsch <Matt_Domsch@dell.com>
27 * remove check for efi_enabled in exit
30 * 26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com>
33 * 21 Apr 2004 - Matt Tolentino <matthew.e.tolentino@intel.com)
34 * converted driver to export variable information via sysfs
35 * and moved to drivers/firmware directory
36 * bumped revision number to v0.07 to reflect conversion & move
38 * 10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com>
39 * fix locking per Peter Chubb's findings
41 * 25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com>
42 * move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_unparse()
44 * 12 Feb 2002 - Matt Domsch <Matt_Domsch@dell.com>
45 * use list_for_each_safe when deleting vars.
46 * remove ifdef CONFIG_SMP around include <linux/smp.h>
47 * v0.04 release to linux-ia64@linuxia64.org
49 * 20 April 2001 - Matt Domsch <Matt_Domsch@dell.com>
50 * Moved vars from /proc/efi to /proc/efi/vars, and made
51 * efi.c own the /proc/efi directory.
52 * v0.03 release to linux-ia64@linuxia64.org
54 * 26 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
55 * At the request of Stephane, moved ownership of /proc/efi
56 * to efi.c, and now efivars lives under /proc/efi/vars.
58 * 12 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
59 * Feedback received from Stephane Eranian incorporated.
60 * efivar_write() checks copy_from_user() return value.
61 * efivar_read/write() returns proper errno.
62 * v0.02 release to linux-ia64@linuxia64.org
64 * 26 February 2001 - Matt Domsch <Matt_Domsch@dell.com>
65 * v0.01 release to linux-ia64@linuxia64.org
68 #include <linux/capability.h>
69 #include <linux/types.h>
70 #include <linux/errno.h>
71 #include <linux/init.h>
73 #include <linux/module.h>
74 #include <linux/string.h>
75 #include <linux/smp.h>
76 #include <linux/efi.h>
77 #include <linux/sysfs.h>
78 #include <linux/kobject.h>
79 #include <linux/device.h>
80 #include <linux/slab.h>
81 #include <linux/pstore.h>
84 #include <linux/ramfs.h>
85 #include <linux/pagemap.h>
87 #include <asm/uaccess.h>
89 #define EFIVARS_VERSION "0.08"
90 #define EFIVARS_DATE "2004-May-17"
92 MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
93 MODULE_DESCRIPTION("sysfs interface to EFI Variables");
94 MODULE_LICENSE("GPL");
95 MODULE_VERSION(EFIVARS_VERSION
);
97 #define DUMP_NAME_LEN 52
100 * Length of a GUID string (strlen("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee"))
101 * not including trailing NUL
106 * The maximum size of VariableName + Data = 1024
107 * Therefore, it's reasonable to save that much
108 * space in each part of the structure,
109 * and we use a page for reading/writing.
112 struct efi_variable
{
113 efi_char16_t VariableName
[1024/sizeof(efi_char16_t
)];
114 efi_guid_t VendorGuid
;
115 unsigned long DataSize
;
119 } __attribute__((packed
));
121 struct efivar_entry
{
122 struct efivars
*efivars
;
123 struct efi_variable var
;
124 struct list_head list
;
128 struct efivar_attribute
{
129 struct attribute attr
;
130 ssize_t (*show
) (struct efivar_entry
*entry
, char *buf
);
131 ssize_t (*store
)(struct efivar_entry
*entry
, const char *buf
, size_t count
);
134 static struct efivars __efivars
;
135 static struct efivar_operations ops
;
137 #define PSTORE_EFI_ATTRIBUTES \
138 (EFI_VARIABLE_NON_VOLATILE | \
139 EFI_VARIABLE_BOOTSERVICE_ACCESS | \
140 EFI_VARIABLE_RUNTIME_ACCESS)
142 #define EFIVAR_ATTR(_name, _mode, _show, _store) \
143 struct efivar_attribute efivar_attr_##_name = { \
144 .attr = {.name = __stringify(_name), .mode = _mode}, \
149 #define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr)
150 #define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj)
153 * Prototype for sysfs creation function
156 efivar_create_sysfs_entry(struct efivars
*efivars
,
157 unsigned long variable_name_size
,
158 efi_char16_t
*variable_name
,
159 efi_guid_t
*vendor_guid
);
162 * Prototype for workqueue functions updating sysfs entry
165 static void efivar_update_sysfs_entries(struct work_struct
*);
166 static DECLARE_WORK(efivar_work
, efivar_update_sysfs_entries
);
168 /* Return the number of unicode characters in data */
170 utf16_strnlen(efi_char16_t
*s
, size_t maxlength
)
172 unsigned long length
= 0;
174 while (*s
++ != 0 && length
< maxlength
)
179 static inline unsigned long
180 utf16_strlen(efi_char16_t
*s
)
182 return utf16_strnlen(s
, ~0UL);
186 * Return the number of bytes is the length of this string
187 * Note: this is NOT the same as the number of unicode characters
189 static inline unsigned long
190 utf16_strsize(efi_char16_t
*data
, unsigned long maxlength
)
192 return utf16_strnlen(data
, maxlength
/sizeof(efi_char16_t
)) * sizeof(efi_char16_t
);
196 utf16_strncmp(const efi_char16_t
*a
, const efi_char16_t
*b
, size_t len
)
205 if (*a
== 0) /* implies *b == 0 */
214 validate_device_path(struct efi_variable
*var
, int match
, u8
*buffer
,
217 struct efi_generic_dev_path
*node
;
220 node
= (struct efi_generic_dev_path
*)buffer
;
222 if (len
< sizeof(*node
))
225 while (offset
<= len
- sizeof(*node
) &&
226 node
->length
>= sizeof(*node
) &&
227 node
->length
<= len
- offset
) {
228 offset
+= node
->length
;
230 if ((node
->type
== EFI_DEV_END_PATH
||
231 node
->type
== EFI_DEV_END_PATH2
) &&
232 node
->sub_type
== EFI_DEV_END_ENTIRE
)
235 node
= (struct efi_generic_dev_path
*)(buffer
+ offset
);
239 * If we're here then either node->length pointed past the end
240 * of the buffer or we reached the end of the buffer without
241 * finding a device path end node.
247 validate_boot_order(struct efi_variable
*var
, int match
, u8
*buffer
,
250 /* An array of 16-bit integers */
258 validate_load_option(struct efi_variable
*var
, int match
, u8
*buffer
,
262 int i
, desclength
= 0, namelen
;
264 namelen
= utf16_strnlen(var
->VariableName
, sizeof(var
->VariableName
));
266 /* Either "Boot" or "Driver" followed by four digits of hex */
267 for (i
= match
; i
< match
+4; i
++) {
268 if (var
->VariableName
[i
] > 127 ||
269 hex_to_bin(var
->VariableName
[i
] & 0xff) < 0)
273 /* Reject it if there's 4 digits of hex and then further content */
274 if (namelen
> match
+ 4)
277 /* A valid entry must be at least 8 bytes */
281 filepathlength
= buffer
[4] | buffer
[5] << 8;
284 * There's no stored length for the description, so it has to be
287 desclength
= utf16_strsize((efi_char16_t
*)(buffer
+ 6), len
- 6) + 2;
289 /* Each boot entry must have a descriptor */
294 * If the sum of the length of the description, the claimed filepath
295 * length and the original header are greater than the length of the
296 * variable, it's malformed
298 if ((desclength
+ filepathlength
+ 6) > len
)
302 * And, finally, check the filepath
304 return validate_device_path(var
, match
, buffer
+ desclength
+ 6,
309 validate_uint16(struct efi_variable
*var
, int match
, u8
*buffer
,
312 /* A single 16-bit integer */
320 validate_ascii_string(struct efi_variable
*var
, int match
, u8
*buffer
,
325 for (i
= 0; i
< len
; i
++) {
336 struct variable_validate
{
338 bool (*validate
)(struct efi_variable
*var
, int match
, u8
*data
,
342 static const struct variable_validate variable_validate
[] = {
343 { "BootNext", validate_uint16
},
344 { "BootOrder", validate_boot_order
},
345 { "DriverOrder", validate_boot_order
},
346 { "Boot*", validate_load_option
},
347 { "Driver*", validate_load_option
},
348 { "ConIn", validate_device_path
},
349 { "ConInDev", validate_device_path
},
350 { "ConOut", validate_device_path
},
351 { "ConOutDev", validate_device_path
},
352 { "ErrOut", validate_device_path
},
353 { "ErrOutDev", validate_device_path
},
354 { "Timeout", validate_uint16
},
355 { "Lang", validate_ascii_string
},
356 { "PlatformLang", validate_ascii_string
},
361 validate_var(struct efi_variable
*var
, u8
*data
, unsigned long len
)
364 u16
*unicode_name
= var
->VariableName
;
366 for (i
= 0; variable_validate
[i
].validate
!= NULL
; i
++) {
367 const char *name
= variable_validate
[i
].name
;
370 for (match
= 0; ; match
++) {
371 char c
= name
[match
];
372 u16 u
= unicode_name
[match
];
374 /* All special variables are plain ascii */
378 /* Wildcard in the matching name means we've matched */
380 return variable_validate
[i
].validate(var
,
383 /* Case sensitive match */
387 /* Reached the end of the string while matching */
389 return variable_validate
[i
].validate(var
,
398 get_var_data_locked(struct efivars
*efivars
, struct efi_variable
*var
)
402 var
->DataSize
= 1024;
403 status
= efivars
->ops
->get_variable(var
->VariableName
,
412 get_var_data(struct efivars
*efivars
, struct efi_variable
*var
)
417 spin_lock_irqsave(&efivars
->lock
, flags
);
418 status
= get_var_data_locked(efivars
, var
);
419 spin_unlock_irqrestore(&efivars
->lock
, flags
);
421 if (status
!= EFI_SUCCESS
) {
422 printk(KERN_WARNING
"efivars: get_variable() failed 0x%lx!\n",
429 efivar_guid_read(struct efivar_entry
*entry
, char *buf
)
431 struct efi_variable
*var
= &entry
->var
;
437 efi_guid_unparse(&var
->VendorGuid
, str
);
439 str
+= sprintf(str
, "\n");
445 efivar_attr_read(struct efivar_entry
*entry
, char *buf
)
447 struct efi_variable
*var
= &entry
->var
;
454 status
= get_var_data(entry
->efivars
, var
);
455 if (status
!= EFI_SUCCESS
)
458 if (var
->Attributes
& EFI_VARIABLE_NON_VOLATILE
)
459 str
+= sprintf(str
, "EFI_VARIABLE_NON_VOLATILE\n");
460 if (var
->Attributes
& EFI_VARIABLE_BOOTSERVICE_ACCESS
)
461 str
+= sprintf(str
, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n");
462 if (var
->Attributes
& EFI_VARIABLE_RUNTIME_ACCESS
)
463 str
+= sprintf(str
, "EFI_VARIABLE_RUNTIME_ACCESS\n");
464 if (var
->Attributes
& EFI_VARIABLE_HARDWARE_ERROR_RECORD
)
465 str
+= sprintf(str
, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n");
466 if (var
->Attributes
& EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS
)
468 "EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n");
469 if (var
->Attributes
&
470 EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS
)
472 "EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n");
473 if (var
->Attributes
& EFI_VARIABLE_APPEND_WRITE
)
474 str
+= sprintf(str
, "EFI_VARIABLE_APPEND_WRITE\n");
479 efivar_size_read(struct efivar_entry
*entry
, char *buf
)
481 struct efi_variable
*var
= &entry
->var
;
488 status
= get_var_data(entry
->efivars
, var
);
489 if (status
!= EFI_SUCCESS
)
492 str
+= sprintf(str
, "0x%lx\n", var
->DataSize
);
497 efivar_data_read(struct efivar_entry
*entry
, char *buf
)
499 struct efi_variable
*var
= &entry
->var
;
505 status
= get_var_data(entry
->efivars
, var
);
506 if (status
!= EFI_SUCCESS
)
509 memcpy(buf
, var
->Data
, var
->DataSize
);
510 return var
->DataSize
;
513 * We allow each variable to be edited via rewriting the
514 * entire efi variable structure.
517 efivar_store_raw(struct efivar_entry
*entry
, const char *buf
, size_t count
)
519 struct efi_variable
*new_var
, *var
= &entry
->var
;
520 struct efivars
*efivars
= entry
->efivars
;
521 efi_status_t status
= EFI_NOT_FOUND
;
523 if (count
!= sizeof(struct efi_variable
))
526 new_var
= (struct efi_variable
*)buf
;
528 * If only updating the variable data, then the name
529 * and guid should remain the same
531 if (memcmp(new_var
->VariableName
, var
->VariableName
, sizeof(var
->VariableName
)) ||
532 efi_guidcmp(new_var
->VendorGuid
, var
->VendorGuid
)) {
533 printk(KERN_ERR
"efivars: Cannot edit the wrong variable!\n");
537 if ((new_var
->DataSize
<= 0) || (new_var
->Attributes
== 0)){
538 printk(KERN_ERR
"efivars: DataSize & Attributes must be valid!\n");
542 if ((new_var
->Attributes
& ~EFI_VARIABLE_MASK
) != 0 ||
543 validate_var(new_var
, new_var
->Data
, new_var
->DataSize
) == false) {
544 printk(KERN_ERR
"efivars: Malformed variable content\n");
548 spin_lock_irq(&efivars
->lock
);
549 status
= efivars
->ops
->set_variable(new_var
->VariableName
,
550 &new_var
->VendorGuid
,
555 spin_unlock_irq(&efivars
->lock
);
557 if (status
!= EFI_SUCCESS
) {
558 printk(KERN_WARNING
"efivars: set_variable() failed: status=%lx\n",
563 memcpy(&entry
->var
, new_var
, count
);
568 efivar_show_raw(struct efivar_entry
*entry
, char *buf
)
570 struct efi_variable
*var
= &entry
->var
;
576 status
= get_var_data(entry
->efivars
, var
);
577 if (status
!= EFI_SUCCESS
)
580 memcpy(buf
, var
, sizeof(*var
));
585 * Generic read/write functions that call the specific functions of
588 static ssize_t
efivar_attr_show(struct kobject
*kobj
, struct attribute
*attr
,
591 struct efivar_entry
*var
= to_efivar_entry(kobj
);
592 struct efivar_attribute
*efivar_attr
= to_efivar_attr(attr
);
595 if (!capable(CAP_SYS_ADMIN
))
598 if (efivar_attr
->show
) {
599 ret
= efivar_attr
->show(var
, buf
);
604 static ssize_t
efivar_attr_store(struct kobject
*kobj
, struct attribute
*attr
,
605 const char *buf
, size_t count
)
607 struct efivar_entry
*var
= to_efivar_entry(kobj
);
608 struct efivar_attribute
*efivar_attr
= to_efivar_attr(attr
);
611 if (!capable(CAP_SYS_ADMIN
))
614 if (efivar_attr
->store
)
615 ret
= efivar_attr
->store(var
, buf
, count
);
620 static const struct sysfs_ops efivar_attr_ops
= {
621 .show
= efivar_attr_show
,
622 .store
= efivar_attr_store
,
625 static void efivar_release(struct kobject
*kobj
)
627 struct efivar_entry
*var
= container_of(kobj
, struct efivar_entry
, kobj
);
631 static EFIVAR_ATTR(guid
, 0400, efivar_guid_read
, NULL
);
632 static EFIVAR_ATTR(attributes
, 0400, efivar_attr_read
, NULL
);
633 static EFIVAR_ATTR(size
, 0400, efivar_size_read
, NULL
);
634 static EFIVAR_ATTR(data
, 0400, efivar_data_read
, NULL
);
635 static EFIVAR_ATTR(raw_var
, 0600, efivar_show_raw
, efivar_store_raw
);
637 static struct attribute
*def_attrs
[] = {
638 &efivar_attr_guid
.attr
,
639 &efivar_attr_size
.attr
,
640 &efivar_attr_attributes
.attr
,
641 &efivar_attr_data
.attr
,
642 &efivar_attr_raw_var
.attr
,
646 static struct kobj_type efivar_ktype
= {
647 .release
= efivar_release
,
648 .sysfs_ops
= &efivar_attr_ops
,
649 .default_attrs
= def_attrs
,
653 efivar_unregister(struct efivar_entry
*var
)
655 kobject_put(&var
->kobj
);
658 static int efivarfs_file_open(struct inode
*inode
, struct file
*file
)
660 file
->private_data
= inode
->i_private
;
664 static int efi_status_to_err(efi_status_t status
)
669 case EFI_INVALID_PARAMETER
:
672 case EFI_OUT_OF_RESOURCES
:
675 case EFI_DEVICE_ERROR
:
678 case EFI_WRITE_PROTECTED
:
681 case EFI_SECURITY_VIOLATION
:
694 static ssize_t
efivarfs_file_write(struct file
*file
,
695 const char __user
*userbuf
, size_t count
, loff_t
*ppos
)
697 struct efivar_entry
*var
= file
->private_data
;
698 struct efivars
*efivars
;
702 struct inode
*inode
= file
->f_mapping
->host
;
703 unsigned long datasize
= count
- sizeof(attributes
);
704 unsigned long newdatasize
;
705 u64 storage_size
, remaining_size
, max_size
;
708 if (count
< sizeof(attributes
))
711 if (copy_from_user(&attributes
, userbuf
, sizeof(attributes
)))
714 if (attributes
& ~(EFI_VARIABLE_MASK
))
717 efivars
= var
->efivars
;
720 * Ensure that the user can't allocate arbitrarily large
721 * amounts of memory. Pick a default size of 64K if
722 * QueryVariableInfo() isn't supported by the firmware.
724 spin_lock_irq(&efivars
->lock
);
726 if (!efivars
->ops
->query_variable_info
)
727 status
= EFI_UNSUPPORTED
;
729 const struct efivar_operations
*fops
= efivars
->ops
;
730 status
= fops
->query_variable_info(attributes
, &storage_size
,
731 &remaining_size
, &max_size
);
734 spin_unlock_irq(&efivars
->lock
);
736 if (status
!= EFI_SUCCESS
) {
737 if (status
!= EFI_UNSUPPORTED
)
738 return efi_status_to_err(status
);
740 remaining_size
= 65536;
743 if (datasize
> remaining_size
)
746 data
= kmalloc(datasize
, GFP_KERNEL
);
750 if (copy_from_user(data
, userbuf
+ sizeof(attributes
), datasize
)) {
755 if (validate_var(&var
->var
, data
, datasize
) == false) {
761 * The lock here protects the get_variable call, the conditional
762 * set_variable call, and removal of the variable from the efivars
763 * list (in the case of an authenticated delete).
765 spin_lock_irq(&efivars
->lock
);
767 status
= efivars
->ops
->set_variable(var
->var
.VariableName
,
768 &var
->var
.VendorGuid
,
769 attributes
, datasize
,
772 if (status
!= EFI_SUCCESS
) {
773 spin_unlock_irq(&efivars
->lock
);
776 return efi_status_to_err(status
);
782 * Writing to the variable may have caused a change in size (which
783 * could either be an append or an overwrite), or the variable to be
784 * deleted. Perform a GetVariable() so we can tell what actually
788 status
= efivars
->ops
->get_variable(var
->var
.VariableName
,
789 &var
->var
.VendorGuid
,
793 if (status
== EFI_BUFFER_TOO_SMALL
) {
794 spin_unlock_irq(&efivars
->lock
);
795 mutex_lock(&inode
->i_mutex
);
796 i_size_write(inode
, newdatasize
+ sizeof(attributes
));
797 mutex_unlock(&inode
->i_mutex
);
799 } else if (status
== EFI_NOT_FOUND
) {
800 list_del(&var
->list
);
801 spin_unlock_irq(&efivars
->lock
);
802 efivar_unregister(var
);
804 d_delete(file
->f_dentry
);
805 dput(file
->f_dentry
);
808 spin_unlock_irq(&efivars
->lock
);
809 pr_warn("efivarfs: inconsistent EFI variable implementation? "
810 "status = %lx\n", status
);
819 static ssize_t
efivarfs_file_read(struct file
*file
, char __user
*userbuf
,
820 size_t count
, loff_t
*ppos
)
822 struct efivar_entry
*var
= file
->private_data
;
823 struct efivars
*efivars
= var
->efivars
;
825 unsigned long datasize
= 0;
830 spin_lock_irq(&efivars
->lock
);
831 status
= efivars
->ops
->get_variable(var
->var
.VariableName
,
832 &var
->var
.VendorGuid
,
833 &attributes
, &datasize
, NULL
);
834 spin_unlock_irq(&efivars
->lock
);
836 if (status
!= EFI_BUFFER_TOO_SMALL
)
837 return efi_status_to_err(status
);
839 data
= kmalloc(datasize
+ sizeof(attributes
), GFP_KERNEL
);
844 spin_lock_irq(&efivars
->lock
);
845 status
= efivars
->ops
->get_variable(var
->var
.VariableName
,
846 &var
->var
.VendorGuid
,
847 &attributes
, &datasize
,
848 (data
+ sizeof(attributes
)));
849 spin_unlock_irq(&efivars
->lock
);
851 if (status
!= EFI_SUCCESS
) {
852 size
= efi_status_to_err(status
);
856 memcpy(data
, &attributes
, sizeof(attributes
));
857 size
= simple_read_from_buffer(userbuf
, count
, ppos
,
858 data
, datasize
+ sizeof(attributes
));
865 static void efivarfs_evict_inode(struct inode
*inode
)
870 static const struct super_operations efivarfs_ops
= {
871 .statfs
= simple_statfs
,
872 .drop_inode
= generic_delete_inode
,
873 .evict_inode
= efivarfs_evict_inode
,
874 .show_options
= generic_show_options
,
877 static struct super_block
*efivarfs_sb
;
879 static const struct inode_operations efivarfs_dir_inode_operations
;
881 static const struct file_operations efivarfs_file_operations
= {
882 .open
= efivarfs_file_open
,
883 .read
= efivarfs_file_read
,
884 .write
= efivarfs_file_write
,
888 static struct inode
*efivarfs_get_inode(struct super_block
*sb
,
889 const struct inode
*dir
, int mode
, dev_t dev
)
891 struct inode
*inode
= new_inode(sb
);
894 inode
->i_ino
= get_next_ino();
895 inode
->i_mode
= mode
;
896 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
897 switch (mode
& S_IFMT
) {
899 inode
->i_fop
= &efivarfs_file_operations
;
902 inode
->i_op
= &efivarfs_dir_inode_operations
;
903 inode
->i_fop
= &simple_dir_operations
;
911 static void efivarfs_hex_to_guid(const char *str
, efi_guid_t
*guid
)
913 guid
->b
[0] = hex_to_bin(str
[6]) << 4 | hex_to_bin(str
[7]);
914 guid
->b
[1] = hex_to_bin(str
[4]) << 4 | hex_to_bin(str
[5]);
915 guid
->b
[2] = hex_to_bin(str
[2]) << 4 | hex_to_bin(str
[3]);
916 guid
->b
[3] = hex_to_bin(str
[0]) << 4 | hex_to_bin(str
[1]);
917 guid
->b
[4] = hex_to_bin(str
[11]) << 4 | hex_to_bin(str
[12]);
918 guid
->b
[5] = hex_to_bin(str
[9]) << 4 | hex_to_bin(str
[10]);
919 guid
->b
[6] = hex_to_bin(str
[16]) << 4 | hex_to_bin(str
[17]);
920 guid
->b
[7] = hex_to_bin(str
[14]) << 4 | hex_to_bin(str
[15]);
921 guid
->b
[8] = hex_to_bin(str
[19]) << 4 | hex_to_bin(str
[20]);
922 guid
->b
[9] = hex_to_bin(str
[21]) << 4 | hex_to_bin(str
[22]);
923 guid
->b
[10] = hex_to_bin(str
[24]) << 4 | hex_to_bin(str
[25]);
924 guid
->b
[11] = hex_to_bin(str
[26]) << 4 | hex_to_bin(str
[27]);
925 guid
->b
[12] = hex_to_bin(str
[28]) << 4 | hex_to_bin(str
[29]);
926 guid
->b
[13] = hex_to_bin(str
[30]) << 4 | hex_to_bin(str
[31]);
927 guid
->b
[14] = hex_to_bin(str
[32]) << 4 | hex_to_bin(str
[33]);
928 guid
->b
[15] = hex_to_bin(str
[34]) << 4 | hex_to_bin(str
[35]);
931 static int efivarfs_create(struct inode
*dir
, struct dentry
*dentry
,
932 umode_t mode
, bool excl
)
935 struct efivars
*efivars
= &__efivars
;
936 struct efivar_entry
*var
;
937 int namelen
, i
= 0, err
= 0;
940 * We need a GUID, plus at least one letter for the variable name,
941 * plus the '-' separator
943 if (dentry
->d_name
.len
< GUID_LEN
+ 2)
946 inode
= efivarfs_get_inode(dir
->i_sb
, dir
, mode
, 0);
950 var
= kzalloc(sizeof(struct efivar_entry
), GFP_KERNEL
);
956 /* length of the variable name itself: remove GUID and separator */
957 namelen
= dentry
->d_name
.len
- GUID_LEN
- 1;
959 efivarfs_hex_to_guid(dentry
->d_name
.name
+ namelen
+ 1,
960 &var
->var
.VendorGuid
);
962 for (i
= 0; i
< namelen
; i
++)
963 var
->var
.VariableName
[i
] = dentry
->d_name
.name
[i
];
965 var
->var
.VariableName
[i
] = '\0';
967 inode
->i_private
= var
;
968 var
->efivars
= efivars
;
969 var
->kobj
.kset
= efivars
->kset
;
971 err
= kobject_init_and_add(&var
->kobj
, &efivar_ktype
, NULL
, "%s",
972 dentry
->d_name
.name
);
976 kobject_uevent(&var
->kobj
, KOBJ_ADD
);
977 spin_lock_irq(&efivars
->lock
);
978 list_add(&var
->list
, &efivars
->list
);
979 spin_unlock_irq(&efivars
->lock
);
980 d_instantiate(dentry
, inode
);
990 static int efivarfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
992 struct efivar_entry
*var
= dentry
->d_inode
->i_private
;
993 struct efivars
*efivars
= var
->efivars
;
996 spin_lock_irq(&efivars
->lock
);
998 status
= efivars
->ops
->set_variable(var
->var
.VariableName
,
999 &var
->var
.VendorGuid
,
1002 if (status
== EFI_SUCCESS
|| status
== EFI_NOT_FOUND
) {
1003 list_del(&var
->list
);
1004 spin_unlock_irq(&efivars
->lock
);
1005 efivar_unregister(var
);
1006 drop_nlink(dentry
->d_inode
);
1011 spin_unlock_irq(&efivars
->lock
);
1015 static int efivarfs_fill_super(struct super_block
*sb
, void *data
, int silent
)
1017 struct inode
*inode
= NULL
;
1018 struct dentry
*root
;
1019 struct efivar_entry
*entry
, *n
;
1020 struct efivars
*efivars
= &__efivars
;
1025 sb
->s_maxbytes
= MAX_LFS_FILESIZE
;
1026 sb
->s_blocksize
= PAGE_CACHE_SIZE
;
1027 sb
->s_blocksize_bits
= PAGE_CACHE_SHIFT
;
1028 sb
->s_magic
= EFIVARFS_MAGIC
;
1029 sb
->s_op
= &efivarfs_ops
;
1030 sb
->s_time_gran
= 1;
1032 inode
= efivarfs_get_inode(sb
, NULL
, S_IFDIR
| 0755, 0);
1035 inode
->i_op
= &efivarfs_dir_inode_operations
;
1037 root
= d_make_root(inode
);
1042 list_for_each_entry_safe(entry
, n
, &efivars
->list
, list
) {
1043 struct dentry
*dentry
, *root
= efivarfs_sb
->s_root
;
1044 unsigned long size
= 0;
1049 len
= utf16_strlen(entry
->var
.VariableName
);
1051 /* name, plus '-', plus GUID, plus NUL*/
1052 name
= kmalloc(len
+ 1 + GUID_LEN
+ 1, GFP_ATOMIC
);
1056 for (i
= 0; i
< len
; i
++)
1057 name
[i
] = entry
->var
.VariableName
[i
] & 0xFF;
1061 efi_guid_unparse(&entry
->var
.VendorGuid
, name
+ len
+ 1);
1063 name
[len
+GUID_LEN
+1] = '\0';
1065 inode
= efivarfs_get_inode(efivarfs_sb
, root
->d_inode
,
1070 dentry
= d_alloc_name(root
, name
);
1074 /* copied by the above to local storage in the dentry. */
1077 spin_lock_irq(&efivars
->lock
);
1078 efivars
->ops
->get_variable(entry
->var
.VariableName
,
1079 &entry
->var
.VendorGuid
,
1080 &entry
->var
.Attributes
,
1083 spin_unlock_irq(&efivars
->lock
);
1085 mutex_lock(&inode
->i_mutex
);
1086 inode
->i_private
= entry
;
1087 i_size_write(inode
, size
+4);
1088 mutex_unlock(&inode
->i_mutex
);
1089 d_add(dentry
, inode
);
1102 static struct dentry
*efivarfs_mount(struct file_system_type
*fs_type
,
1103 int flags
, const char *dev_name
, void *data
)
1105 return mount_single(fs_type
, flags
, data
, efivarfs_fill_super
);
1108 static void efivarfs_kill_sb(struct super_block
*sb
)
1110 kill_litter_super(sb
);
1114 static struct file_system_type efivarfs_type
= {
1116 .mount
= efivarfs_mount
,
1117 .kill_sb
= efivarfs_kill_sb
,
1120 static const struct inode_operations efivarfs_dir_inode_operations
= {
1121 .lookup
= simple_lookup
,
1122 .unlink
= efivarfs_unlink
,
1123 .create
= efivarfs_create
,
1126 static struct pstore_info efi_pstore_info
;
1128 #ifdef CONFIG_PSTORE
1130 static int efi_pstore_open(struct pstore_info
*psi
)
1132 struct efivars
*efivars
= psi
->data
;
1134 spin_lock_irq(&efivars
->lock
);
1135 efivars
->walk_entry
= list_first_entry(&efivars
->list
,
1136 struct efivar_entry
, list
);
1140 static int efi_pstore_close(struct pstore_info
*psi
)
1142 struct efivars
*efivars
= psi
->data
;
1144 spin_unlock_irq(&efivars
->lock
);
1148 static ssize_t
efi_pstore_read(u64
*id
, enum pstore_type_id
*type
,
1149 int *count
, struct timespec
*timespec
,
1150 char **buf
, struct pstore_info
*psi
)
1152 efi_guid_t vendor
= LINUX_EFI_CRASH_GUID
;
1153 struct efivars
*efivars
= psi
->data
;
1154 char name
[DUMP_NAME_LEN
];
1157 unsigned int part
, size
;
1160 while (&efivars
->walk_entry
->list
!= &efivars
->list
) {
1161 if (!efi_guidcmp(efivars
->walk_entry
->var
.VendorGuid
,
1163 for (i
= 0; i
< DUMP_NAME_LEN
; i
++) {
1164 name
[i
] = efivars
->walk_entry
->var
.VariableName
[i
];
1166 if (sscanf(name
, "dump-type%u-%u-%d-%lu",
1167 type
, &part
, &cnt
, &time
) == 4) {
1170 timespec
->tv_sec
= time
;
1171 timespec
->tv_nsec
= 0;
1172 } else if (sscanf(name
, "dump-type%u-%u-%lu",
1173 type
, &part
, &time
) == 3) {
1175 * Check if an old format,
1176 * which doesn't support holding
1177 * multiple logs, remains.
1181 timespec
->tv_sec
= time
;
1182 timespec
->tv_nsec
= 0;
1184 efivars
->walk_entry
= list_entry(
1185 efivars
->walk_entry
->list
.next
,
1186 struct efivar_entry
, list
);
1190 get_var_data_locked(efivars
, &efivars
->walk_entry
->var
);
1191 size
= efivars
->walk_entry
->var
.DataSize
;
1192 *buf
= kmalloc(size
, GFP_KERNEL
);
1195 memcpy(*buf
, efivars
->walk_entry
->var
.Data
,
1197 efivars
->walk_entry
= list_entry(
1198 efivars
->walk_entry
->list
.next
,
1199 struct efivar_entry
, list
);
1202 efivars
->walk_entry
= list_entry(efivars
->walk_entry
->list
.next
,
1203 struct efivar_entry
, list
);
1208 static int efi_pstore_write(enum pstore_type_id type
,
1209 enum kmsg_dump_reason reason
, u64
*id
,
1210 unsigned int part
, int count
, size_t size
,
1211 struct pstore_info
*psi
)
1213 char name
[DUMP_NAME_LEN
];
1214 efi_char16_t efi_name
[DUMP_NAME_LEN
];
1215 efi_guid_t vendor
= LINUX_EFI_CRASH_GUID
;
1216 struct efivars
*efivars
= psi
->data
;
1218 u64 storage_space
, remaining_space
, max_variable_size
;
1219 efi_status_t status
= EFI_NOT_FOUND
;
1220 unsigned long flags
;
1222 if (pstore_cannot_block_path(reason
)) {
1224 * If the lock is taken by another cpu in non-blocking path,
1225 * this driver returns without entering firmware to avoid
1228 if (!spin_trylock_irqsave(&efivars
->lock
, flags
))
1231 spin_lock_irqsave(&efivars
->lock
, flags
);
1234 * Check if there is a space enough to log.
1235 * size: a size of logging data
1236 * DUMP_NAME_LEN * 2: a maximum size of variable name
1238 status
= efivars
->ops
->query_variable_info(PSTORE_EFI_ATTRIBUTES
,
1241 &max_variable_size
);
1242 if (status
|| remaining_space
< size
+ DUMP_NAME_LEN
* 2) {
1243 spin_unlock_irqrestore(&efivars
->lock
, flags
);
1248 sprintf(name
, "dump-type%u-%u-%d-%lu", type
, part
, count
,
1251 for (i
= 0; i
< DUMP_NAME_LEN
; i
++)
1252 efi_name
[i
] = name
[i
];
1254 efivars
->ops
->set_variable(efi_name
, &vendor
, PSTORE_EFI_ATTRIBUTES
,
1257 spin_unlock_irqrestore(&efivars
->lock
, flags
);
1259 if (reason
== KMSG_DUMP_OOPS
)
1260 schedule_work(&efivar_work
);
1266 static int efi_pstore_erase(enum pstore_type_id type
, u64 id
, int count
,
1267 struct timespec time
, struct pstore_info
*psi
)
1269 char name
[DUMP_NAME_LEN
];
1270 efi_char16_t efi_name
[DUMP_NAME_LEN
];
1271 char name_old
[DUMP_NAME_LEN
];
1272 efi_char16_t efi_name_old
[DUMP_NAME_LEN
];
1273 efi_guid_t vendor
= LINUX_EFI_CRASH_GUID
;
1274 struct efivars
*efivars
= psi
->data
;
1275 struct efivar_entry
*entry
, *found
= NULL
;
1278 sprintf(name
, "dump-type%u-%u-%d-%lu", type
, (unsigned int)id
, count
,
1281 spin_lock_irq(&efivars
->lock
);
1283 for (i
= 0; i
< DUMP_NAME_LEN
; i
++)
1284 efi_name
[i
] = name
[i
];
1287 * Clean up an entry with the same name
1290 list_for_each_entry(entry
, &efivars
->list
, list
) {
1291 get_var_data_locked(efivars
, &entry
->var
);
1293 if (efi_guidcmp(entry
->var
.VendorGuid
, vendor
))
1295 if (utf16_strncmp(entry
->var
.VariableName
, efi_name
,
1296 utf16_strlen(efi_name
))) {
1298 * Check if an old format,
1299 * which doesn't support holding
1300 * multiple logs, remains.
1302 sprintf(name_old
, "dump-type%u-%u-%lu", type
,
1303 (unsigned int)id
, time
.tv_sec
);
1305 for (i
= 0; i
< DUMP_NAME_LEN
; i
++)
1306 efi_name_old
[i
] = name_old
[i
];
1308 if (utf16_strncmp(entry
->var
.VariableName
, efi_name_old
,
1309 utf16_strlen(efi_name_old
)))
1315 efivars
->ops
->set_variable(entry
->var
.VariableName
,
1316 &entry
->var
.VendorGuid
,
1317 PSTORE_EFI_ATTRIBUTES
,
1323 list_del(&found
->list
);
1325 spin_unlock_irq(&efivars
->lock
);
1328 efivar_unregister(found
);
1333 static int efi_pstore_open(struct pstore_info
*psi
)
1338 static int efi_pstore_close(struct pstore_info
*psi
)
1343 static ssize_t
efi_pstore_read(u64
*id
, enum pstore_type_id
*type
, int *count
,
1344 struct timespec
*timespec
,
1345 char **buf
, struct pstore_info
*psi
)
1350 static int efi_pstore_write(enum pstore_type_id type
,
1351 enum kmsg_dump_reason reason
, u64
*id
,
1352 unsigned int part
, int count
, size_t size
,
1353 struct pstore_info
*psi
)
1358 static int efi_pstore_erase(enum pstore_type_id type
, u64 id
, int count
,
1359 struct timespec time
, struct pstore_info
*psi
)
1365 static struct pstore_info efi_pstore_info
= {
1366 .owner
= THIS_MODULE
,
1368 .open
= efi_pstore_open
,
1369 .close
= efi_pstore_close
,
1370 .read
= efi_pstore_read
,
1371 .write
= efi_pstore_write
,
1372 .erase
= efi_pstore_erase
,
1375 static ssize_t
efivar_create(struct file
*filp
, struct kobject
*kobj
,
1376 struct bin_attribute
*bin_attr
,
1377 char *buf
, loff_t pos
, size_t count
)
1379 struct efi_variable
*new_var
= (struct efi_variable
*)buf
;
1380 struct efivars
*efivars
= bin_attr
->private;
1381 struct efivar_entry
*search_efivar
, *n
;
1382 unsigned long strsize1
, strsize2
;
1383 efi_status_t status
= EFI_NOT_FOUND
;
1386 if (!capable(CAP_SYS_ADMIN
))
1389 if ((new_var
->Attributes
& ~EFI_VARIABLE_MASK
) != 0 ||
1390 validate_var(new_var
, new_var
->Data
, new_var
->DataSize
) == false) {
1391 printk(KERN_ERR
"efivars: Malformed variable content\n");
1395 spin_lock_irq(&efivars
->lock
);
1398 * Does this variable already exist?
1400 list_for_each_entry_safe(search_efivar
, n
, &efivars
->list
, list
) {
1401 strsize1
= utf16_strsize(search_efivar
->var
.VariableName
, 1024);
1402 strsize2
= utf16_strsize(new_var
->VariableName
, 1024);
1403 if (strsize1
== strsize2
&&
1404 !memcmp(&(search_efivar
->var
.VariableName
),
1405 new_var
->VariableName
, strsize1
) &&
1406 !efi_guidcmp(search_efivar
->var
.VendorGuid
,
1407 new_var
->VendorGuid
)) {
1413 spin_unlock_irq(&efivars
->lock
);
1417 /* now *really* create the variable via EFI */
1418 status
= efivars
->ops
->set_variable(new_var
->VariableName
,
1419 &new_var
->VendorGuid
,
1420 new_var
->Attributes
,
1424 if (status
!= EFI_SUCCESS
) {
1425 printk(KERN_WARNING
"efivars: set_variable() failed: status=%lx\n",
1427 spin_unlock_irq(&efivars
->lock
);
1430 spin_unlock_irq(&efivars
->lock
);
1432 /* Create the entry in sysfs. Locking is not required here */
1433 status
= efivar_create_sysfs_entry(efivars
,
1434 utf16_strsize(new_var
->VariableName
,
1436 new_var
->VariableName
,
1437 &new_var
->VendorGuid
);
1439 printk(KERN_WARNING
"efivars: variable created, but sysfs entry wasn't.\n");
1444 static ssize_t
efivar_delete(struct file
*filp
, struct kobject
*kobj
,
1445 struct bin_attribute
*bin_attr
,
1446 char *buf
, loff_t pos
, size_t count
)
1448 struct efi_variable
*del_var
= (struct efi_variable
*)buf
;
1449 struct efivars
*efivars
= bin_attr
->private;
1450 struct efivar_entry
*search_efivar
, *n
;
1451 unsigned long strsize1
, strsize2
;
1452 efi_status_t status
= EFI_NOT_FOUND
;
1455 if (!capable(CAP_SYS_ADMIN
))
1458 spin_lock_irq(&efivars
->lock
);
1461 * Does this variable already exist?
1463 list_for_each_entry_safe(search_efivar
, n
, &efivars
->list
, list
) {
1464 strsize1
= utf16_strsize(search_efivar
->var
.VariableName
, 1024);
1465 strsize2
= utf16_strsize(del_var
->VariableName
, 1024);
1466 if (strsize1
== strsize2
&&
1467 !memcmp(&(search_efivar
->var
.VariableName
),
1468 del_var
->VariableName
, strsize1
) &&
1469 !efi_guidcmp(search_efivar
->var
.VendorGuid
,
1470 del_var
->VendorGuid
)) {
1476 spin_unlock_irq(&efivars
->lock
);
1479 /* force the Attributes/DataSize to 0 to ensure deletion */
1480 del_var
->Attributes
= 0;
1481 del_var
->DataSize
= 0;
1483 status
= efivars
->ops
->set_variable(del_var
->VariableName
,
1484 &del_var
->VendorGuid
,
1485 del_var
->Attributes
,
1489 if (status
!= EFI_SUCCESS
) {
1490 printk(KERN_WARNING
"efivars: set_variable() failed: status=%lx\n",
1492 spin_unlock_irq(&efivars
->lock
);
1495 list_del(&search_efivar
->list
);
1496 /* We need to release this lock before unregistering. */
1497 spin_unlock_irq(&efivars
->lock
);
1498 efivar_unregister(search_efivar
);
1500 /* It's dead Jim.... */
1504 static bool variable_is_present(efi_char16_t
*variable_name
, efi_guid_t
*vendor
)
1506 struct efivar_entry
*entry
, *n
;
1507 struct efivars
*efivars
= &__efivars
;
1508 unsigned long strsize1
, strsize2
;
1511 strsize1
= utf16_strsize(variable_name
, 1024);
1512 list_for_each_entry_safe(entry
, n
, &efivars
->list
, list
) {
1513 strsize2
= utf16_strsize(entry
->var
.VariableName
, 1024);
1514 if (strsize1
== strsize2
&&
1515 !memcmp(variable_name
, &(entry
->var
.VariableName
),
1517 !efi_guidcmp(entry
->var
.VendorGuid
,
1526 static void efivar_update_sysfs_entries(struct work_struct
*work
)
1528 struct efivars
*efivars
= &__efivars
;
1530 efi_char16_t
*variable_name
;
1531 unsigned long variable_name_size
= 1024;
1532 efi_status_t status
= EFI_NOT_FOUND
;
1535 /* Add new sysfs entries */
1537 variable_name
= kzalloc(variable_name_size
, GFP_KERNEL
);
1538 if (!variable_name
) {
1539 pr_err("efivars: Memory allocation failed.\n");
1543 spin_lock_irq(&efivars
->lock
);
1546 variable_name_size
= 1024;
1547 status
= efivars
->ops
->get_next_variable(
1548 &variable_name_size
,
1551 if (status
!= EFI_SUCCESS
) {
1554 if (!variable_is_present(variable_name
,
1561 spin_unlock_irq(&efivars
->lock
);
1564 kfree(variable_name
);
1567 efivar_create_sysfs_entry(efivars
,
1569 variable_name
, &vendor
);
1574 * Let's not leave out systab information that snuck into
1575 * the efivars driver
1577 static ssize_t
systab_show(struct kobject
*kobj
,
1578 struct kobj_attribute
*attr
, char *buf
)
1585 if (efi
.mps
!= EFI_INVALID_TABLE_ADDR
)
1586 str
+= sprintf(str
, "MPS=0x%lx\n", efi
.mps
);
1587 if (efi
.acpi20
!= EFI_INVALID_TABLE_ADDR
)
1588 str
+= sprintf(str
, "ACPI20=0x%lx\n", efi
.acpi20
);
1589 if (efi
.acpi
!= EFI_INVALID_TABLE_ADDR
)
1590 str
+= sprintf(str
, "ACPI=0x%lx\n", efi
.acpi
);
1591 if (efi
.smbios
!= EFI_INVALID_TABLE_ADDR
)
1592 str
+= sprintf(str
, "SMBIOS=0x%lx\n", efi
.smbios
);
1593 if (efi
.hcdp
!= EFI_INVALID_TABLE_ADDR
)
1594 str
+= sprintf(str
, "HCDP=0x%lx\n", efi
.hcdp
);
1595 if (efi
.boot_info
!= EFI_INVALID_TABLE_ADDR
)
1596 str
+= sprintf(str
, "BOOTINFO=0x%lx\n", efi
.boot_info
);
1597 if (efi
.uga
!= EFI_INVALID_TABLE_ADDR
)
1598 str
+= sprintf(str
, "UGA=0x%lx\n", efi
.uga
);
1603 static struct kobj_attribute efi_attr_systab
=
1604 __ATTR(systab
, 0400, systab_show
, NULL
);
1606 static struct attribute
*efi_subsys_attrs
[] = {
1607 &efi_attr_systab
.attr
,
1608 NULL
, /* maybe more in the future? */
1611 static struct attribute_group efi_subsys_attr_group
= {
1612 .attrs
= efi_subsys_attrs
,
1615 static struct kobject
*efi_kobj
;
1618 * efivar_create_sysfs_entry()
1620 * variable_name_size = number of bytes required to hold
1621 * variable_name (not counting the NULL
1622 * character at the end.
1623 * efivars->lock is not held on entry or exit.
1624 * Returns 1 on failure, 0 on success
1627 efivar_create_sysfs_entry(struct efivars
*efivars
,
1628 unsigned long variable_name_size
,
1629 efi_char16_t
*variable_name
,
1630 efi_guid_t
*vendor_guid
)
1632 int i
, short_name_size
;
1634 struct efivar_entry
*new_efivar
;
1637 * Length of the variable bytes in ASCII, plus the '-' separator,
1638 * plus the GUID, plus trailing NUL
1640 short_name_size
= variable_name_size
/ sizeof(efi_char16_t
)
1643 short_name
= kzalloc(short_name_size
, GFP_KERNEL
);
1644 new_efivar
= kzalloc(sizeof(struct efivar_entry
), GFP_KERNEL
);
1646 if (!short_name
|| !new_efivar
) {
1652 new_efivar
->efivars
= efivars
;
1653 memcpy(new_efivar
->var
.VariableName
, variable_name
,
1654 variable_name_size
);
1655 memcpy(&(new_efivar
->var
.VendorGuid
), vendor_guid
, sizeof(efi_guid_t
));
1657 /* Convert Unicode to normal chars (assume top bits are 0),
1659 for (i
=0; i
< (int)(variable_name_size
/ sizeof(efi_char16_t
)); i
++) {
1660 short_name
[i
] = variable_name
[i
] & 0xFF;
1662 /* This is ugly, but necessary to separate one vendor's
1663 private variables from another's. */
1665 *(short_name
+ strlen(short_name
)) = '-';
1666 efi_guid_unparse(vendor_guid
, short_name
+ strlen(short_name
));
1668 new_efivar
->kobj
.kset
= efivars
->kset
;
1669 i
= kobject_init_and_add(&new_efivar
->kobj
, &efivar_ktype
, NULL
,
1677 kobject_uevent(&new_efivar
->kobj
, KOBJ_ADD
);
1681 spin_lock_irq(&efivars
->lock
);
1682 list_add(&new_efivar
->list
, &efivars
->list
);
1683 spin_unlock_irq(&efivars
->lock
);
1689 create_efivars_bin_attributes(struct efivars
*efivars
)
1691 struct bin_attribute
*attr
;
1695 attr
= kzalloc(sizeof(*attr
), GFP_KERNEL
);
1699 attr
->attr
.name
= "new_var";
1700 attr
->attr
.mode
= 0200;
1701 attr
->write
= efivar_create
;
1702 attr
->private = efivars
;
1703 efivars
->new_var
= attr
;
1706 attr
= kzalloc(sizeof(*attr
), GFP_KERNEL
);
1711 attr
->attr
.name
= "del_var";
1712 attr
->attr
.mode
= 0200;
1713 attr
->write
= efivar_delete
;
1714 attr
->private = efivars
;
1715 efivars
->del_var
= attr
;
1717 sysfs_bin_attr_init(efivars
->new_var
);
1718 sysfs_bin_attr_init(efivars
->del_var
);
1721 error
= sysfs_create_bin_file(&efivars
->kset
->kobj
,
1724 printk(KERN_ERR
"efivars: unable to create new_var sysfs file"
1725 " due to error %d\n", error
);
1728 error
= sysfs_create_bin_file(&efivars
->kset
->kobj
,
1731 printk(KERN_ERR
"efivars: unable to create del_var sysfs file"
1732 " due to error %d\n", error
);
1733 sysfs_remove_bin_file(&efivars
->kset
->kobj
,
1740 kfree(efivars
->del_var
);
1741 efivars
->del_var
= NULL
;
1742 kfree(efivars
->new_var
);
1743 efivars
->new_var
= NULL
;
1747 void unregister_efivars(struct efivars
*efivars
)
1749 struct efivar_entry
*entry
, *n
;
1751 list_for_each_entry_safe(entry
, n
, &efivars
->list
, list
) {
1752 spin_lock_irq(&efivars
->lock
);
1753 list_del(&entry
->list
);
1754 spin_unlock_irq(&efivars
->lock
);
1755 efivar_unregister(entry
);
1757 if (efivars
->new_var
)
1758 sysfs_remove_bin_file(&efivars
->kset
->kobj
, efivars
->new_var
);
1759 if (efivars
->del_var
)
1760 sysfs_remove_bin_file(&efivars
->kset
->kobj
, efivars
->del_var
);
1761 kfree(efivars
->new_var
);
1762 kfree(efivars
->del_var
);
1763 kobject_put(efivars
->kobject
);
1764 kset_unregister(efivars
->kset
);
1766 EXPORT_SYMBOL_GPL(unregister_efivars
);
1768 int register_efivars(struct efivars
*efivars
,
1769 const struct efivar_operations
*ops
,
1770 struct kobject
*parent_kobj
)
1772 efi_status_t status
= EFI_NOT_FOUND
;
1773 efi_guid_t vendor_guid
;
1774 efi_char16_t
*variable_name
;
1775 unsigned long variable_name_size
= 1024;
1778 variable_name
= kzalloc(variable_name_size
, GFP_KERNEL
);
1779 if (!variable_name
) {
1780 printk(KERN_ERR
"efivars: Memory allocation failed.\n");
1784 spin_lock_init(&efivars
->lock
);
1785 INIT_LIST_HEAD(&efivars
->list
);
1788 efivars
->kset
= kset_create_and_add("vars", NULL
, parent_kobj
);
1789 if (!efivars
->kset
) {
1790 printk(KERN_ERR
"efivars: Subsystem registration failed.\n");
1795 efivars
->kobject
= kobject_create_and_add("efivars", parent_kobj
);
1796 if (!efivars
->kobject
) {
1797 pr_err("efivars: Subsystem registration failed.\n");
1799 kset_unregister(efivars
->kset
);
1804 * Per EFI spec, the maximum storage allocated for both
1805 * the variable name and variable data is 1024 bytes.
1809 variable_name_size
= 1024;
1811 status
= ops
->get_next_variable(&variable_name_size
,
1816 efivar_create_sysfs_entry(efivars
,
1824 printk(KERN_WARNING
"efivars: get_next_variable: status=%lx\n",
1826 status
= EFI_NOT_FOUND
;
1829 } while (status
!= EFI_NOT_FOUND
);
1831 error
= create_efivars_bin_attributes(efivars
);
1833 unregister_efivars(efivars
);
1835 efivars
->efi_pstore_info
= efi_pstore_info
;
1837 efivars
->efi_pstore_info
.buf
= kmalloc(4096, GFP_KERNEL
);
1838 if (efivars
->efi_pstore_info
.buf
) {
1839 efivars
->efi_pstore_info
.bufsize
= 1024;
1840 efivars
->efi_pstore_info
.data
= efivars
;
1841 spin_lock_init(&efivars
->efi_pstore_info
.buf_lock
);
1842 pstore_register(&efivars
->efi_pstore_info
);
1845 register_filesystem(&efivarfs_type
);
1848 kfree(variable_name
);
1852 EXPORT_SYMBOL_GPL(register_efivars
);
1855 * For now we register the efi subsystem with the firmware subsystem
1856 * and the vars subsystem with the efi subsystem. In the future, it
1857 * might make sense to split off the efi subsystem into its own
1858 * driver, but for now only efivars will register with it, so just
1867 printk(KERN_INFO
"EFI Variables Facility v%s %s\n", EFIVARS_VERSION
,
1870 if (!efi_enabled(EFI_RUNTIME_SERVICES
))
1873 /* For now we'll register the efi directory at /sys/firmware/efi */
1874 efi_kobj
= kobject_create_and_add("efi", firmware_kobj
);
1876 printk(KERN_ERR
"efivars: Firmware registration failed.\n");
1880 ops
.get_variable
= efi
.get_variable
;
1881 ops
.set_variable
= efi
.set_variable
;
1882 ops
.get_next_variable
= efi
.get_next_variable
;
1883 ops
.query_variable_info
= efi
.query_variable_info
;
1885 error
= register_efivars(&__efivars
, &ops
, efi_kobj
);
1889 /* Don't forget the systab entry */
1890 error
= sysfs_create_group(efi_kobj
, &efi_subsys_attr_group
);
1893 "efivars: Sysfs attribute export failed with error %d.\n",
1895 goto err_unregister
;
1901 unregister_efivars(&__efivars
);
1903 kobject_put(efi_kobj
);
1910 cancel_work_sync(&efivar_work
);
1912 if (efi_enabled(EFI_RUNTIME_SERVICES
)) {
1913 unregister_efivars(&__efivars
);
1914 kobject_put(efi_kobj
);
1918 module_init(efivars_init
);
1919 module_exit(efivars_exit
);