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