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