efivars: Make efivars bin_attributes dynamic
[deliverable/linux.git] / drivers / firmware / efivars.c
CommitLineData
1da177e4
LT
1/*
2 * EFI Variables - efivars.c
3 *
4 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
5 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
6 *
7 * This code takes all variables accessible from EFI runtime and
8 * exports them via sysfs
9 *
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.
14 *
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.
19 *
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
23 *
24 * Changelog:
25 *
26 * 17 May 2004 - Matt Domsch <Matt_Domsch@dell.com>
27 * remove check for efi_enabled in exit
28 * add MODULE_VERSION
29 *
30 * 26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com>
31 * minor bug fixes
32 *
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
37 *
38 * 10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com>
39 * fix locking per Peter Chubb's findings
40 *
41 * 25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com>
42 * move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_unparse()
43 *
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
48 *
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
53 *
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.
57 *
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
63 *
64 * 26 February 2001 - Matt Domsch <Matt_Domsch@dell.com>
65 * v0.01 release to linux-ia64@linuxia64.org
66 */
67
c59ede7b 68#include <linux/capability.h>
1da177e4
LT
69#include <linux/types.h>
70#include <linux/errno.h>
71#include <linux/init.h>
1da177e4
LT
72#include <linux/mm.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>
5a0e3ad6 80#include <linux/slab.h>
1da177e4
LT
81
82#include <asm/uaccess.h>
83
84#define EFIVARS_VERSION "0.08"
85#define EFIVARS_DATE "2004-May-17"
86
87MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
88MODULE_DESCRIPTION("sysfs interface to EFI Variables");
89MODULE_LICENSE("GPL");
90MODULE_VERSION(EFIVARS_VERSION);
91
29422693
MW
92struct efivars {
93 /*
94 * ->lock protects two things:
95 * 1) ->list - adds, removals, reads, writes
96 * 2) efi.[gs]et_variable() calls.
97 * It must not be held when creating sysfs entries or calling kmalloc.
98 * efi.get_next_variable() is only called from efivars_init(),
99 * which is protected by the BKL, so that path is safe.
100 */
101 spinlock_t lock;
102 struct list_head list;
103 struct kset *kset;
d502fbb0 104 struct bin_attribute *new_var, *del_var;
29422693
MW
105};
106static struct efivars __efivars;
107static struct efivars *efivars = &__efivars;
1da177e4
LT
108
109/*
110 * The maximum size of VariableName + Data = 1024
111 * Therefore, it's reasonable to save that much
112 * space in each part of the structure,
113 * and we use a page for reading/writing.
114 */
115
116struct efi_variable {
117 efi_char16_t VariableName[1024/sizeof(efi_char16_t)];
118 efi_guid_t VendorGuid;
119 unsigned long DataSize;
120 __u8 Data[1024];
121 efi_status_t Status;
122 __u32 Attributes;
123} __attribute__((packed));
124
125
126struct efivar_entry {
127 struct efi_variable var;
128 struct list_head list;
129 struct kobject kobj;
130};
131
1da177e4
LT
132struct efivar_attribute {
133 struct attribute attr;
134 ssize_t (*show) (struct efivar_entry *entry, char *buf);
135 ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count);
136};
137
138
1da177e4
LT
139#define EFIVAR_ATTR(_name, _mode, _show, _store) \
140struct efivar_attribute efivar_attr_##_name = { \
7b595756 141 .attr = {.name = __stringify(_name), .mode = _mode}, \
1da177e4
LT
142 .show = _show, \
143 .store = _store, \
144};
145
1da177e4
LT
146#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr)
147#define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj)
148
149/*
150 * Prototype for sysfs creation function
151 */
152static int
153efivar_create_sysfs_entry(unsigned long variable_name_size,
154 efi_char16_t *variable_name,
155 efi_guid_t *vendor_guid);
156
157/* Return the number of unicode characters in data */
158static unsigned long
159utf8_strlen(efi_char16_t *data, unsigned long maxlength)
160{
161 unsigned long length = 0;
162
163 while (*data++ != 0 && length < maxlength)
164 length++;
165 return length;
166}
167
168/*
169 * Return the number of bytes is the length of this string
170 * Note: this is NOT the same as the number of unicode characters
171 */
172static inline unsigned long
173utf8_strsize(efi_char16_t *data, unsigned long maxlength)
174{
175 return utf8_strlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t);
176}
177
178static efi_status_t
179get_var_data(struct efi_variable *var)
180{
181 efi_status_t status;
182
29422693 183 spin_lock(&efivars->lock);
1da177e4
LT
184 var->DataSize = 1024;
185 status = efi.get_variable(var->VariableName,
186 &var->VendorGuid,
187 &var->Attributes,
188 &var->DataSize,
189 var->Data);
29422693 190 spin_unlock(&efivars->lock);
1da177e4
LT
191 if (status != EFI_SUCCESS) {
192 printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n",
193 status);
194 }
195 return status;
196}
197
198static ssize_t
199efivar_guid_read(struct efivar_entry *entry, char *buf)
200{
201 struct efi_variable *var = &entry->var;
202 char *str = buf;
203
204 if (!entry || !buf)
205 return 0;
206
207 efi_guid_unparse(&var->VendorGuid, str);
208 str += strlen(str);
209 str += sprintf(str, "\n");
210
211 return str - buf;
212}
213
214static ssize_t
215efivar_attr_read(struct efivar_entry *entry, char *buf)
216{
217 struct efi_variable *var = &entry->var;
218 char *str = buf;
219 efi_status_t status;
220
221 if (!entry || !buf)
222 return -EINVAL;
223
224 status = get_var_data(var);
225 if (status != EFI_SUCCESS)
226 return -EIO;
227
228 if (var->Attributes & 0x1)
229 str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n");
230 if (var->Attributes & 0x2)
231 str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n");
232 if (var->Attributes & 0x4)
233 str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n");
234 return str - buf;
235}
236
237static ssize_t
238efivar_size_read(struct efivar_entry *entry, char *buf)
239{
240 struct efi_variable *var = &entry->var;
241 char *str = buf;
242 efi_status_t status;
243
244 if (!entry || !buf)
245 return -EINVAL;
246
247 status = get_var_data(var);
248 if (status != EFI_SUCCESS)
249 return -EIO;
250
251 str += sprintf(str, "0x%lx\n", var->DataSize);
252 return str - buf;
253}
254
255static ssize_t
256efivar_data_read(struct efivar_entry *entry, char *buf)
257{
258 struct efi_variable *var = &entry->var;
259 efi_status_t status;
260
261 if (!entry || !buf)
262 return -EINVAL;
263
264 status = get_var_data(var);
265 if (status != EFI_SUCCESS)
266 return -EIO;
267
268 memcpy(buf, var->Data, var->DataSize);
269 return var->DataSize;
270}
271/*
272 * We allow each variable to be edited via rewriting the
273 * entire efi variable structure.
274 */
275static ssize_t
276efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
277{
278 struct efi_variable *new_var, *var = &entry->var;
279 efi_status_t status = EFI_NOT_FOUND;
280
281 if (count != sizeof(struct efi_variable))
282 return -EINVAL;
283
284 new_var = (struct efi_variable *)buf;
285 /*
286 * If only updating the variable data, then the name
287 * and guid should remain the same
288 */
289 if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) ||
290 efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) {
291 printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n");
292 return -EINVAL;
293 }
294
295 if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){
296 printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n");
297 return -EINVAL;
298 }
299
29422693 300 spin_lock(&efivars->lock);
1da177e4
LT
301 status = efi.set_variable(new_var->VariableName,
302 &new_var->VendorGuid,
303 new_var->Attributes,
304 new_var->DataSize,
305 new_var->Data);
306
29422693 307 spin_unlock(&efivars->lock);
1da177e4
LT
308
309 if (status != EFI_SUCCESS) {
310 printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
311 status);
312 return -EIO;
313 }
314
315 memcpy(&entry->var, new_var, count);
316 return count;
317}
318
319static ssize_t
320efivar_show_raw(struct efivar_entry *entry, char *buf)
321{
322 struct efi_variable *var = &entry->var;
323 efi_status_t status;
324
325 if (!entry || !buf)
326 return 0;
327
328 status = get_var_data(var);
329 if (status != EFI_SUCCESS)
330 return -EIO;
331
332 memcpy(buf, var, sizeof(*var));
333 return sizeof(*var);
334}
335
336/*
337 * Generic read/write functions that call the specific functions of
338 * the atttributes...
339 */
340static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr,
341 char *buf)
342{
343 struct efivar_entry *var = to_efivar_entry(kobj);
344 struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
70f2817a 345 ssize_t ret = -EIO;
1da177e4
LT
346
347 if (!capable(CAP_SYS_ADMIN))
348 return -EACCES;
349
350 if (efivar_attr->show) {
351 ret = efivar_attr->show(var, buf);
352 }
353 return ret;
354}
355
356static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr,
357 const char *buf, size_t count)
358{
359 struct efivar_entry *var = to_efivar_entry(kobj);
360 struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
70f2817a 361 ssize_t ret = -EIO;
1da177e4
LT
362
363 if (!capable(CAP_SYS_ADMIN))
364 return -EACCES;
365
366 if (efivar_attr->store)
367 ret = efivar_attr->store(var, buf, count);
368
369 return ret;
370}
371
52cf25d0 372static const struct sysfs_ops efivar_attr_ops = {
1da177e4
LT
373 .show = efivar_attr_show,
374 .store = efivar_attr_store,
375};
376
377static void efivar_release(struct kobject *kobj)
378{
379 struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj);
1da177e4
LT
380 kfree(var);
381}
382
383static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL);
384static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL);
385static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL);
386static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL);
387static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw);
388
389static struct attribute *def_attrs[] = {
390 &efivar_attr_guid.attr,
391 &efivar_attr_size.attr,
392 &efivar_attr_attributes.attr,
393 &efivar_attr_data.attr,
394 &efivar_attr_raw_var.attr,
395 NULL,
396};
397
e89a4116 398static struct kobj_type efivar_ktype = {
1da177e4
LT
399 .release = efivar_release,
400 .sysfs_ops = &efivar_attr_ops,
401 .default_attrs = def_attrs,
402};
403
1da177e4
LT
404static inline void
405efivar_unregister(struct efivar_entry *var)
406{
c10997f6 407 kobject_put(&var->kobj);
1da177e4
LT
408}
409
410
2c3c8bea 411static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
97fa5bb7
GKH
412 struct bin_attribute *bin_attr,
413 char *buf, loff_t pos, size_t count)
1da177e4
LT
414{
415 struct efi_variable *new_var = (struct efi_variable *)buf;
496a0fc8 416 struct efivar_entry *search_efivar, *n;
1da177e4 417 unsigned long strsize1, strsize2;
1da177e4
LT
418 efi_status_t status = EFI_NOT_FOUND;
419 int found = 0;
420
421 if (!capable(CAP_SYS_ADMIN))
422 return -EACCES;
423
29422693 424 spin_lock(&efivars->lock);
1da177e4
LT
425
426 /*
427 * Does this variable already exist?
428 */
29422693 429 list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
1da177e4
LT
430 strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024);
431 strsize2 = utf8_strsize(new_var->VariableName, 1024);
432 if (strsize1 == strsize2 &&
433 !memcmp(&(search_efivar->var.VariableName),
434 new_var->VariableName, strsize1) &&
435 !efi_guidcmp(search_efivar->var.VendorGuid,
436 new_var->VendorGuid)) {
437 found = 1;
438 break;
439 }
440 }
441 if (found) {
29422693 442 spin_unlock(&efivars->lock);
1da177e4
LT
443 return -EINVAL;
444 }
445
446 /* now *really* create the variable via EFI */
447 status = efi.set_variable(new_var->VariableName,
448 &new_var->VendorGuid,
449 new_var->Attributes,
450 new_var->DataSize,
451 new_var->Data);
452
453 if (status != EFI_SUCCESS) {
454 printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
455 status);
29422693 456 spin_unlock(&efivars->lock);
1da177e4
LT
457 return -EIO;
458 }
29422693 459 spin_unlock(&efivars->lock);
1da177e4
LT
460
461 /* Create the entry in sysfs. Locking is not required here */
462 status = efivar_create_sysfs_entry(utf8_strsize(new_var->VariableName,
463 1024), new_var->VariableName, &new_var->VendorGuid);
464 if (status) {
465 printk(KERN_WARNING "efivars: variable created, but sysfs entry wasn't.\n");
466 }
467 return count;
468}
469
2c3c8bea 470static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
97fa5bb7
GKH
471 struct bin_attribute *bin_attr,
472 char *buf, loff_t pos, size_t count)
1da177e4
LT
473{
474 struct efi_variable *del_var = (struct efi_variable *)buf;
496a0fc8 475 struct efivar_entry *search_efivar, *n;
1da177e4 476 unsigned long strsize1, strsize2;
1da177e4
LT
477 efi_status_t status = EFI_NOT_FOUND;
478 int found = 0;
479
480 if (!capable(CAP_SYS_ADMIN))
481 return -EACCES;
482
29422693 483 spin_lock(&efivars->lock);
1da177e4
LT
484
485 /*
486 * Does this variable already exist?
487 */
29422693 488 list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
1da177e4
LT
489 strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024);
490 strsize2 = utf8_strsize(del_var->VariableName, 1024);
491 if (strsize1 == strsize2 &&
492 !memcmp(&(search_efivar->var.VariableName),
493 del_var->VariableName, strsize1) &&
494 !efi_guidcmp(search_efivar->var.VendorGuid,
495 del_var->VendorGuid)) {
496 found = 1;
497 break;
498 }
499 }
500 if (!found) {
29422693 501 spin_unlock(&efivars->lock);
1da177e4
LT
502 return -EINVAL;
503 }
504 /* force the Attributes/DataSize to 0 to ensure deletion */
505 del_var->Attributes = 0;
506 del_var->DataSize = 0;
507
508 status = efi.set_variable(del_var->VariableName,
509 &del_var->VendorGuid,
510 del_var->Attributes,
511 del_var->DataSize,
512 del_var->Data);
513
514 if (status != EFI_SUCCESS) {
515 printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
516 status);
29422693 517 spin_unlock(&efivars->lock);
1da177e4
LT
518 return -EIO;
519 }
496a0fc8 520 list_del(&search_efivar->list);
1da177e4 521 /* We need to release this lock before unregistering. */
29422693 522 spin_unlock(&efivars->lock);
1da177e4
LT
523 efivar_unregister(search_efivar);
524
525 /* It's dead Jim.... */
526 return count;
527}
528
1da177e4
LT
529/*
530 * Let's not leave out systab information that snuck into
531 * the efivars driver
532 */
334c6307
GKH
533static ssize_t systab_show(struct kobject *kobj,
534 struct kobj_attribute *attr, char *buf)
1da177e4
LT
535{
536 char *str = buf;
537
334c6307 538 if (!kobj || !buf)
1da177e4
LT
539 return -EINVAL;
540
b2c99e3c
BH
541 if (efi.mps != EFI_INVALID_TABLE_ADDR)
542 str += sprintf(str, "MPS=0x%lx\n", efi.mps);
543 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
544 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
545 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
546 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
547 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
548 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
549 if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
550 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
551 if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
552 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
553 if (efi.uga != EFI_INVALID_TABLE_ADDR)
554 str += sprintf(str, "UGA=0x%lx\n", efi.uga);
1da177e4
LT
555
556 return str - buf;
557}
558
334c6307
GKH
559static struct kobj_attribute efi_attr_systab =
560 __ATTR(systab, 0400, systab_show, NULL);
1da177e4 561
334c6307
GKH
562static struct attribute *efi_subsys_attrs[] = {
563 &efi_attr_systab.attr,
1da177e4
LT
564 NULL, /* maybe more in the future? */
565};
566
334c6307
GKH
567static struct attribute_group efi_subsys_attr_group = {
568 .attrs = efi_subsys_attrs,
569};
570
bc87d2fe 571static struct kobject *efi_kobj;
1da177e4
LT
572
573/*
574 * efivar_create_sysfs_entry()
575 * Requires:
576 * variable_name_size = number of bytes required to hold
577 * variable_name (not counting the NULL
578 * character at the end.
29422693 579 * efivars->lock is not held on entry or exit.
1da177e4
LT
580 * Returns 1 on failure, 0 on success
581 */
582static int
583efivar_create_sysfs_entry(unsigned long variable_name_size,
584 efi_char16_t *variable_name,
585 efi_guid_t *vendor_guid)
586{
587 int i, short_name_size = variable_name_size / sizeof(efi_char16_t) + 38;
588 char *short_name;
589 struct efivar_entry *new_efivar;
590
9c215384
DS
591 short_name = kzalloc(short_name_size + 1, GFP_KERNEL);
592 new_efivar = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL);
1da177e4
LT
593
594 if (!short_name || !new_efivar) {
0933ad9c
JJ
595 kfree(short_name);
596 kfree(new_efivar);
1da177e4
LT
597 return 1;
598 }
1da177e4
LT
599
600 memcpy(new_efivar->var.VariableName, variable_name,
601 variable_name_size);
602 memcpy(&(new_efivar->var.VendorGuid), vendor_guid, sizeof(efi_guid_t));
603
604 /* Convert Unicode to normal chars (assume top bits are 0),
605 ala UTF-8 */
606 for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) {
607 short_name[i] = variable_name[i] & 0xFF;
608 }
609 /* This is ugly, but necessary to separate one vendor's
610 private variables from another's. */
611
612 *(short_name + strlen(short_name)) = '-';
613 efi_guid_unparse(vendor_guid, short_name + strlen(short_name));
614
29422693 615 new_efivar->kobj.kset = efivars->kset;
d6d292c4
GKH
616 i = kobject_init_and_add(&new_efivar->kobj, &efivar_ktype, NULL,
617 "%s", short_name);
69b2186c
JG
618 if (i) {
619 kfree(short_name);
620 kfree(new_efivar);
621 return 1;
622 }
1da177e4 623
d6d292c4 624 kobject_uevent(&new_efivar->kobj, KOBJ_ADD);
0933ad9c
JJ
625 kfree(short_name);
626 short_name = NULL;
1da177e4 627
29422693
MW
628 spin_lock(&efivars->lock);
629 list_add(&new_efivar->list, &efivars->list);
630 spin_unlock(&efivars->lock);
1da177e4
LT
631
632 return 0;
633}
d502fbb0
MW
634
635static int
636create_efivars_bin_attributes(struct efivars *efivars)
637{
638 struct bin_attribute *attr;
639 int error;
640
641 /* new_var */
642 attr = kzalloc(sizeof(*attr), GFP_KERNEL);
643 if (!attr)
644 return -ENOMEM;
645
646 attr->attr.name = "new_var";
647 attr->attr.mode = 0200;
648 attr->write = efivar_create;
649 attr->private = efivars;
650 efivars->new_var = attr;
651
652 /* del_var */
653 attr = kzalloc(sizeof(*attr), GFP_KERNEL);
654 if (!attr) {
655 error = -ENOMEM;
656 goto out_free;
657 }
658 attr->attr.name = "del_var";
659 attr->attr.mode = 0200;
660 attr->write = efivar_delete;
661 attr->private = efivars;
662 efivars->del_var = attr;
663
664 sysfs_bin_attr_init(efivars->new_var);
665 sysfs_bin_attr_init(efivars->del_var);
666
667 /* Register */
668 error = sysfs_create_bin_file(&efivars->kset->kobj,
669 efivars->new_var);
670 if (error) {
671 printk(KERN_ERR "efivars: unable to create new_var sysfs file"
672 " due to error %d\n", error);
673 goto out_free;
674 }
675 error = sysfs_create_bin_file(&efivars->kset->kobj,
676 efivars->del_var);
677 if (error) {
678 printk(KERN_ERR "efivars: unable to create del_var sysfs file"
679 " due to error %d\n", error);
680 sysfs_remove_bin_file(&efivars->kset->kobj,
681 efivars->new_var);
682 goto out_free;
683 }
684
685 return 0;
686out_free:
687 kfree(efivars->new_var);
688 efivars->new_var = NULL;
689 kfree(efivars->new_var);
690 efivars->new_var = NULL;
691 return error;
692}
693
1da177e4
LT
694/*
695 * For now we register the efi subsystem with the firmware subsystem
696 * and the vars subsystem with the efi subsystem. In the future, it
697 * might make sense to split off the efi subsystem into its own
698 * driver, but for now only efivars will register with it, so just
699 * include it here.
700 */
701
702static int __init
703efivars_init(void)
704{
705 efi_status_t status = EFI_NOT_FOUND;
706 efi_guid_t vendor_guid;
707 efi_char16_t *variable_name;
1da177e4 708 unsigned long variable_name_size = 1024;
334c6307 709 int error = 0;
1da177e4
LT
710
711 if (!efi_enabled)
712 return -ENODEV;
713
9c215384 714 variable_name = kzalloc(variable_name_size, GFP_KERNEL);
1da177e4
LT
715 if (!variable_name) {
716 printk(KERN_ERR "efivars: Memory allocation failed.\n");
717 return -ENOMEM;
718 }
719
1da177e4
LT
720 printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION,
721 EFIVARS_DATE);
722
bc87d2fe
GKH
723 /* For now we'll register the efi directory at /sys/firmware/efi */
724 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
725 if (!efi_kobj) {
89a07e34
GKH
726 printk(KERN_ERR "efivars: Firmware registration failed.\n");
727 error = -ENOMEM;
1da177e4
LT
728 goto out_free;
729 }
730
29422693
MW
731 spin_lock_init(&efivars->lock);
732 INIT_LIST_HEAD(&efivars->list);
733
734 efivars->kset = kset_create_and_add("vars", NULL, efi_kobj);
735 if (!efivars->kset) {
66ac831e
GKH
736 printk(KERN_ERR "efivars: Subsystem registration failed.\n");
737 error = -ENOMEM;
1da177e4
LT
738 goto out_firmware_unregister;
739 }
740
741 /*
742 * Per EFI spec, the maximum storage allocated for both
743 * the variable name and variable data is 1024 bytes.
744 */
745
746 do {
747 variable_name_size = 1024;
748
749 status = efi.get_next_variable(&variable_name_size,
750 variable_name,
751 &vendor_guid);
752 switch (status) {
753 case EFI_SUCCESS:
754 efivar_create_sysfs_entry(variable_name_size,
755 variable_name,
756 &vendor_guid);
757 break;
758 case EFI_NOT_FOUND:
759 break;
760 default:
761 printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n",
762 status);
763 status = EFI_NOT_FOUND;
764 break;
765 }
766 } while (status != EFI_NOT_FOUND);
767
d502fbb0 768 error = create_efivars_bin_attributes(efivars);
1da177e4
LT
769
770 /* Don't forget the systab entry */
bc87d2fe 771 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
1da177e4
LT
772 if (error)
773 printk(KERN_ERR "efivars: Sysfs attribute export failed with error %d.\n", error);
774 else
775 goto out_free;
776
29422693 777 kset_unregister(efivars->kset);
1da177e4
LT
778
779out_firmware_unregister:
c10997f6 780 kobject_put(efi_kobj);
1da177e4
LT
781
782out_free:
783 kfree(variable_name);
784
785 return error;
786}
787
788static void __exit
789efivars_exit(void)
790{
496a0fc8 791 struct efivar_entry *entry, *n;
1da177e4 792
29422693
MW
793 list_for_each_entry_safe(entry, n, &efivars->list, list) {
794 spin_lock(&efivars->lock);
496a0fc8 795 list_del(&entry->list);
29422693 796 spin_unlock(&efivars->lock);
496a0fc8
MD
797 efivar_unregister(entry);
798 }
d502fbb0
MW
799 if (efivars->new_var)
800 sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var);
801 if (efivars->del_var)
802 sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var);
803 kfree(efivars->new_var);
804 kfree(efivars->del_var);
29422693 805 kset_unregister(efivars->kset);
c10997f6 806 kobject_put(efi_kobj);
1da177e4
LT
807}
808
809module_init(efivars_init);
810module_exit(efivars_exit);
811
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