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 | ||
29422693 MW |
92 | struct 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 | 105 | }; |
1da177e4 LT |
106 | |
107 | /* | |
108 | * The maximum size of VariableName + Data = 1024 | |
109 | * Therefore, it's reasonable to save that much | |
110 | * space in each part of the structure, | |
111 | * and we use a page for reading/writing. | |
112 | */ | |
113 | ||
114 | struct efi_variable { | |
115 | efi_char16_t VariableName[1024/sizeof(efi_char16_t)]; | |
116 | efi_guid_t VendorGuid; | |
117 | unsigned long DataSize; | |
118 | __u8 Data[1024]; | |
119 | efi_status_t Status; | |
120 | __u32 Attributes; | |
121 | } __attribute__((packed)); | |
122 | ||
123 | ||
124 | struct efivar_entry { | |
4142ef14 | 125 | struct efivars *efivars; |
1da177e4 LT |
126 | struct efi_variable var; |
127 | struct list_head list; | |
128 | struct kobject kobj; | |
129 | }; | |
130 | ||
1da177e4 LT |
131 | struct efivar_attribute { |
132 | struct attribute attr; | |
133 | ssize_t (*show) (struct efivar_entry *entry, char *buf); | |
134 | ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count); | |
135 | }; | |
136 | ||
137 | ||
1da177e4 LT |
138 | #define EFIVAR_ATTR(_name, _mode, _show, _store) \ |
139 | struct efivar_attribute efivar_attr_##_name = { \ | |
7b595756 | 140 | .attr = {.name = __stringify(_name), .mode = _mode}, \ |
1da177e4 LT |
141 | .show = _show, \ |
142 | .store = _store, \ | |
143 | }; | |
144 | ||
1da177e4 LT |
145 | #define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr) |
146 | #define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj) | |
147 | ||
148 | /* | |
149 | * Prototype for sysfs creation function | |
150 | */ | |
151 | static int | |
4142ef14 MW |
152 | efivar_create_sysfs_entry(struct efivars *efivars, |
153 | unsigned long variable_name_size, | |
154 | efi_char16_t *variable_name, | |
155 | efi_guid_t *vendor_guid); | |
1da177e4 LT |
156 | |
157 | /* Return the number of unicode characters in data */ | |
158 | static unsigned long | |
159 | utf8_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 | */ | |
172 | static inline unsigned long | |
173 | utf8_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 | ||
178 | static efi_status_t | |
4142ef14 | 179 | get_var_data(struct efivars *efivars, struct efi_variable *var) |
1da177e4 LT |
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 | ||
198 | static ssize_t | |
199 | efivar_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 | ||
214 | static ssize_t | |
215 | efivar_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 | ||
4142ef14 | 224 | status = get_var_data(entry->efivars, var); |
1da177e4 LT |
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 | ||
237 | static ssize_t | |
238 | efivar_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 | ||
4142ef14 | 247 | status = get_var_data(entry->efivars, var); |
1da177e4 LT |
248 | if (status != EFI_SUCCESS) |
249 | return -EIO; | |
250 | ||
251 | str += sprintf(str, "0x%lx\n", var->DataSize); | |
252 | return str - buf; | |
253 | } | |
254 | ||
255 | static ssize_t | |
256 | efivar_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 | ||
4142ef14 | 264 | status = get_var_data(entry->efivars, var); |
1da177e4 LT |
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 | */ | |
275 | static ssize_t | |
276 | efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) | |
277 | { | |
278 | struct efi_variable *new_var, *var = &entry->var; | |
4142ef14 | 279 | struct efivars *efivars = entry->efivars; |
1da177e4 LT |
280 | efi_status_t status = EFI_NOT_FOUND; |
281 | ||
282 | if (count != sizeof(struct efi_variable)) | |
283 | return -EINVAL; | |
284 | ||
285 | new_var = (struct efi_variable *)buf; | |
286 | /* | |
287 | * If only updating the variable data, then the name | |
288 | * and guid should remain the same | |
289 | */ | |
290 | if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) || | |
291 | efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) { | |
292 | printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n"); | |
293 | return -EINVAL; | |
294 | } | |
295 | ||
296 | if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){ | |
297 | printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n"); | |
298 | return -EINVAL; | |
299 | } | |
300 | ||
29422693 | 301 | spin_lock(&efivars->lock); |
1da177e4 LT |
302 | status = efi.set_variable(new_var->VariableName, |
303 | &new_var->VendorGuid, | |
304 | new_var->Attributes, | |
305 | new_var->DataSize, | |
306 | new_var->Data); | |
307 | ||
29422693 | 308 | spin_unlock(&efivars->lock); |
1da177e4 LT |
309 | |
310 | if (status != EFI_SUCCESS) { | |
311 | printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", | |
312 | status); | |
313 | return -EIO; | |
314 | } | |
315 | ||
316 | memcpy(&entry->var, new_var, count); | |
317 | return count; | |
318 | } | |
319 | ||
320 | static ssize_t | |
321 | efivar_show_raw(struct efivar_entry *entry, char *buf) | |
322 | { | |
323 | struct efi_variable *var = &entry->var; | |
324 | efi_status_t status; | |
325 | ||
326 | if (!entry || !buf) | |
327 | return 0; | |
328 | ||
4142ef14 | 329 | status = get_var_data(entry->efivars, var); |
1da177e4 LT |
330 | if (status != EFI_SUCCESS) |
331 | return -EIO; | |
332 | ||
333 | memcpy(buf, var, sizeof(*var)); | |
334 | return sizeof(*var); | |
335 | } | |
336 | ||
337 | /* | |
338 | * Generic read/write functions that call the specific functions of | |
339 | * the atttributes... | |
340 | */ | |
341 | static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr, | |
342 | char *buf) | |
343 | { | |
344 | struct efivar_entry *var = to_efivar_entry(kobj); | |
345 | struct efivar_attribute *efivar_attr = to_efivar_attr(attr); | |
70f2817a | 346 | ssize_t ret = -EIO; |
1da177e4 LT |
347 | |
348 | if (!capable(CAP_SYS_ADMIN)) | |
349 | return -EACCES; | |
350 | ||
351 | if (efivar_attr->show) { | |
352 | ret = efivar_attr->show(var, buf); | |
353 | } | |
354 | return ret; | |
355 | } | |
356 | ||
357 | static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr, | |
358 | const char *buf, size_t count) | |
359 | { | |
360 | struct efivar_entry *var = to_efivar_entry(kobj); | |
361 | struct efivar_attribute *efivar_attr = to_efivar_attr(attr); | |
70f2817a | 362 | ssize_t ret = -EIO; |
1da177e4 LT |
363 | |
364 | if (!capable(CAP_SYS_ADMIN)) | |
365 | return -EACCES; | |
366 | ||
367 | if (efivar_attr->store) | |
368 | ret = efivar_attr->store(var, buf, count); | |
369 | ||
370 | return ret; | |
371 | } | |
372 | ||
52cf25d0 | 373 | static const struct sysfs_ops efivar_attr_ops = { |
1da177e4 LT |
374 | .show = efivar_attr_show, |
375 | .store = efivar_attr_store, | |
376 | }; | |
377 | ||
378 | static void efivar_release(struct kobject *kobj) | |
379 | { | |
380 | struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj); | |
1da177e4 LT |
381 | kfree(var); |
382 | } | |
383 | ||
384 | static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL); | |
385 | static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL); | |
386 | static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL); | |
387 | static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL); | |
388 | static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw); | |
389 | ||
390 | static struct attribute *def_attrs[] = { | |
391 | &efivar_attr_guid.attr, | |
392 | &efivar_attr_size.attr, | |
393 | &efivar_attr_attributes.attr, | |
394 | &efivar_attr_data.attr, | |
395 | &efivar_attr_raw_var.attr, | |
396 | NULL, | |
397 | }; | |
398 | ||
e89a4116 | 399 | static struct kobj_type efivar_ktype = { |
1da177e4 LT |
400 | .release = efivar_release, |
401 | .sysfs_ops = &efivar_attr_ops, | |
402 | .default_attrs = def_attrs, | |
403 | }; | |
404 | ||
1da177e4 LT |
405 | static inline void |
406 | efivar_unregister(struct efivar_entry *var) | |
407 | { | |
c10997f6 | 408 | kobject_put(&var->kobj); |
1da177e4 LT |
409 | } |
410 | ||
411 | ||
2c3c8bea | 412 | static ssize_t efivar_create(struct file *filp, struct kobject *kobj, |
97fa5bb7 GKH |
413 | struct bin_attribute *bin_attr, |
414 | char *buf, loff_t pos, size_t count) | |
1da177e4 LT |
415 | { |
416 | struct efi_variable *new_var = (struct efi_variable *)buf; | |
4142ef14 | 417 | struct efivars *efivars = bin_attr->private; |
496a0fc8 | 418 | struct efivar_entry *search_efivar, *n; |
1da177e4 | 419 | unsigned long strsize1, strsize2; |
1da177e4 LT |
420 | efi_status_t status = EFI_NOT_FOUND; |
421 | int found = 0; | |
422 | ||
423 | if (!capable(CAP_SYS_ADMIN)) | |
424 | return -EACCES; | |
425 | ||
29422693 | 426 | spin_lock(&efivars->lock); |
1da177e4 LT |
427 | |
428 | /* | |
429 | * Does this variable already exist? | |
430 | */ | |
29422693 | 431 | list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { |
1da177e4 LT |
432 | strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024); |
433 | strsize2 = utf8_strsize(new_var->VariableName, 1024); | |
434 | if (strsize1 == strsize2 && | |
435 | !memcmp(&(search_efivar->var.VariableName), | |
436 | new_var->VariableName, strsize1) && | |
437 | !efi_guidcmp(search_efivar->var.VendorGuid, | |
438 | new_var->VendorGuid)) { | |
439 | found = 1; | |
440 | break; | |
441 | } | |
442 | } | |
443 | if (found) { | |
29422693 | 444 | spin_unlock(&efivars->lock); |
1da177e4 LT |
445 | return -EINVAL; |
446 | } | |
447 | ||
448 | /* now *really* create the variable via EFI */ | |
449 | status = efi.set_variable(new_var->VariableName, | |
450 | &new_var->VendorGuid, | |
451 | new_var->Attributes, | |
452 | new_var->DataSize, | |
453 | new_var->Data); | |
454 | ||
455 | if (status != EFI_SUCCESS) { | |
456 | printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", | |
457 | status); | |
29422693 | 458 | spin_unlock(&efivars->lock); |
1da177e4 LT |
459 | return -EIO; |
460 | } | |
29422693 | 461 | spin_unlock(&efivars->lock); |
1da177e4 LT |
462 | |
463 | /* Create the entry in sysfs. Locking is not required here */ | |
4142ef14 MW |
464 | status = efivar_create_sysfs_entry(efivars, |
465 | utf8_strsize(new_var->VariableName, | |
466 | 1024), | |
467 | new_var->VariableName, | |
468 | &new_var->VendorGuid); | |
1da177e4 LT |
469 | if (status) { |
470 | printk(KERN_WARNING "efivars: variable created, but sysfs entry wasn't.\n"); | |
471 | } | |
472 | return count; | |
473 | } | |
474 | ||
2c3c8bea | 475 | static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, |
97fa5bb7 GKH |
476 | struct bin_attribute *bin_attr, |
477 | char *buf, loff_t pos, size_t count) | |
1da177e4 LT |
478 | { |
479 | struct efi_variable *del_var = (struct efi_variable *)buf; | |
4142ef14 | 480 | struct efivars *efivars = bin_attr->private; |
496a0fc8 | 481 | struct efivar_entry *search_efivar, *n; |
1da177e4 | 482 | unsigned long strsize1, strsize2; |
1da177e4 LT |
483 | efi_status_t status = EFI_NOT_FOUND; |
484 | int found = 0; | |
485 | ||
486 | if (!capable(CAP_SYS_ADMIN)) | |
487 | return -EACCES; | |
488 | ||
29422693 | 489 | spin_lock(&efivars->lock); |
1da177e4 LT |
490 | |
491 | /* | |
492 | * Does this variable already exist? | |
493 | */ | |
29422693 | 494 | list_for_each_entry_safe(search_efivar, n, &efivars->list, list) { |
1da177e4 LT |
495 | strsize1 = utf8_strsize(search_efivar->var.VariableName, 1024); |
496 | strsize2 = utf8_strsize(del_var->VariableName, 1024); | |
497 | if (strsize1 == strsize2 && | |
498 | !memcmp(&(search_efivar->var.VariableName), | |
499 | del_var->VariableName, strsize1) && | |
500 | !efi_guidcmp(search_efivar->var.VendorGuid, | |
501 | del_var->VendorGuid)) { | |
502 | found = 1; | |
503 | break; | |
504 | } | |
505 | } | |
506 | if (!found) { | |
29422693 | 507 | spin_unlock(&efivars->lock); |
1da177e4 LT |
508 | return -EINVAL; |
509 | } | |
510 | /* force the Attributes/DataSize to 0 to ensure deletion */ | |
511 | del_var->Attributes = 0; | |
512 | del_var->DataSize = 0; | |
513 | ||
514 | status = efi.set_variable(del_var->VariableName, | |
515 | &del_var->VendorGuid, | |
516 | del_var->Attributes, | |
517 | del_var->DataSize, | |
518 | del_var->Data); | |
519 | ||
520 | if (status != EFI_SUCCESS) { | |
521 | printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n", | |
522 | status); | |
29422693 | 523 | spin_unlock(&efivars->lock); |
1da177e4 LT |
524 | return -EIO; |
525 | } | |
496a0fc8 | 526 | list_del(&search_efivar->list); |
1da177e4 | 527 | /* We need to release this lock before unregistering. */ |
29422693 | 528 | spin_unlock(&efivars->lock); |
1da177e4 LT |
529 | efivar_unregister(search_efivar); |
530 | ||
531 | /* It's dead Jim.... */ | |
532 | return count; | |
533 | } | |
534 | ||
1da177e4 LT |
535 | /* |
536 | * Let's not leave out systab information that snuck into | |
537 | * the efivars driver | |
538 | */ | |
334c6307 GKH |
539 | static ssize_t systab_show(struct kobject *kobj, |
540 | struct kobj_attribute *attr, char *buf) | |
1da177e4 LT |
541 | { |
542 | char *str = buf; | |
543 | ||
334c6307 | 544 | if (!kobj || !buf) |
1da177e4 LT |
545 | return -EINVAL; |
546 | ||
b2c99e3c BH |
547 | if (efi.mps != EFI_INVALID_TABLE_ADDR) |
548 | str += sprintf(str, "MPS=0x%lx\n", efi.mps); | |
549 | if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) | |
550 | str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); | |
551 | if (efi.acpi != EFI_INVALID_TABLE_ADDR) | |
552 | str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); | |
553 | if (efi.smbios != EFI_INVALID_TABLE_ADDR) | |
554 | str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); | |
555 | if (efi.hcdp != EFI_INVALID_TABLE_ADDR) | |
556 | str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp); | |
557 | if (efi.boot_info != EFI_INVALID_TABLE_ADDR) | |
558 | str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info); | |
559 | if (efi.uga != EFI_INVALID_TABLE_ADDR) | |
560 | str += sprintf(str, "UGA=0x%lx\n", efi.uga); | |
1da177e4 LT |
561 | |
562 | return str - buf; | |
563 | } | |
564 | ||
334c6307 GKH |
565 | static struct kobj_attribute efi_attr_systab = |
566 | __ATTR(systab, 0400, systab_show, NULL); | |
1da177e4 | 567 | |
334c6307 GKH |
568 | static struct attribute *efi_subsys_attrs[] = { |
569 | &efi_attr_systab.attr, | |
1da177e4 LT |
570 | NULL, /* maybe more in the future? */ |
571 | }; | |
572 | ||
334c6307 GKH |
573 | static struct attribute_group efi_subsys_attr_group = { |
574 | .attrs = efi_subsys_attrs, | |
575 | }; | |
576 | ||
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. | |
29422693 | 585 | * efivars->lock is not held on entry or exit. |
1da177e4 LT |
586 | * Returns 1 on failure, 0 on success |
587 | */ | |
588 | static int | |
4142ef14 MW |
589 | efivar_create_sysfs_entry(struct efivars *efivars, |
590 | unsigned long variable_name_size, | |
591 | efi_char16_t *variable_name, | |
592 | efi_guid_t *vendor_guid) | |
1da177e4 LT |
593 | { |
594 | int i, short_name_size = variable_name_size / sizeof(efi_char16_t) + 38; | |
595 | char *short_name; | |
596 | struct efivar_entry *new_efivar; | |
597 | ||
9c215384 DS |
598 | short_name = kzalloc(short_name_size + 1, GFP_KERNEL); |
599 | new_efivar = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL); | |
1da177e4 LT |
600 | |
601 | if (!short_name || !new_efivar) { | |
0933ad9c JJ |
602 | kfree(short_name); |
603 | kfree(new_efivar); | |
1da177e4 LT |
604 | return 1; |
605 | } | |
1da177e4 | 606 | |
4142ef14 | 607 | new_efivar->efivars = efivars; |
1da177e4 LT |
608 | memcpy(new_efivar->var.VariableName, variable_name, |
609 | variable_name_size); | |
610 | memcpy(&(new_efivar->var.VendorGuid), vendor_guid, sizeof(efi_guid_t)); | |
611 | ||
612 | /* Convert Unicode to normal chars (assume top bits are 0), | |
613 | ala UTF-8 */ | |
614 | for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) { | |
615 | short_name[i] = variable_name[i] & 0xFF; | |
616 | } | |
617 | /* This is ugly, but necessary to separate one vendor's | |
618 | private variables from another's. */ | |
619 | ||
620 | *(short_name + strlen(short_name)) = '-'; | |
621 | efi_guid_unparse(vendor_guid, short_name + strlen(short_name)); | |
622 | ||
29422693 | 623 | new_efivar->kobj.kset = efivars->kset; |
d6d292c4 GKH |
624 | i = kobject_init_and_add(&new_efivar->kobj, &efivar_ktype, NULL, |
625 | "%s", short_name); | |
69b2186c JG |
626 | if (i) { |
627 | kfree(short_name); | |
628 | kfree(new_efivar); | |
629 | return 1; | |
630 | } | |
1da177e4 | 631 | |
d6d292c4 | 632 | kobject_uevent(&new_efivar->kobj, KOBJ_ADD); |
0933ad9c JJ |
633 | kfree(short_name); |
634 | short_name = NULL; | |
1da177e4 | 635 | |
29422693 MW |
636 | spin_lock(&efivars->lock); |
637 | list_add(&new_efivar->list, &efivars->list); | |
638 | spin_unlock(&efivars->lock); | |
1da177e4 LT |
639 | |
640 | return 0; | |
641 | } | |
d502fbb0 MW |
642 | |
643 | static int | |
644 | create_efivars_bin_attributes(struct efivars *efivars) | |
645 | { | |
646 | struct bin_attribute *attr; | |
647 | int error; | |
648 | ||
649 | /* new_var */ | |
650 | attr = kzalloc(sizeof(*attr), GFP_KERNEL); | |
651 | if (!attr) | |
652 | return -ENOMEM; | |
653 | ||
654 | attr->attr.name = "new_var"; | |
655 | attr->attr.mode = 0200; | |
656 | attr->write = efivar_create; | |
657 | attr->private = efivars; | |
658 | efivars->new_var = attr; | |
659 | ||
660 | /* del_var */ | |
661 | attr = kzalloc(sizeof(*attr), GFP_KERNEL); | |
662 | if (!attr) { | |
663 | error = -ENOMEM; | |
664 | goto out_free; | |
665 | } | |
666 | attr->attr.name = "del_var"; | |
667 | attr->attr.mode = 0200; | |
668 | attr->write = efivar_delete; | |
669 | attr->private = efivars; | |
670 | efivars->del_var = attr; | |
671 | ||
672 | sysfs_bin_attr_init(efivars->new_var); | |
673 | sysfs_bin_attr_init(efivars->del_var); | |
674 | ||
675 | /* Register */ | |
676 | error = sysfs_create_bin_file(&efivars->kset->kobj, | |
677 | efivars->new_var); | |
678 | if (error) { | |
679 | printk(KERN_ERR "efivars: unable to create new_var sysfs file" | |
680 | " due to error %d\n", error); | |
681 | goto out_free; | |
682 | } | |
683 | error = sysfs_create_bin_file(&efivars->kset->kobj, | |
684 | efivars->del_var); | |
685 | if (error) { | |
686 | printk(KERN_ERR "efivars: unable to create del_var sysfs file" | |
687 | " due to error %d\n", error); | |
688 | sysfs_remove_bin_file(&efivars->kset->kobj, | |
689 | efivars->new_var); | |
690 | goto out_free; | |
691 | } | |
692 | ||
693 | return 0; | |
694 | out_free: | |
695 | kfree(efivars->new_var); | |
696 | efivars->new_var = NULL; | |
697 | kfree(efivars->new_var); | |
698 | efivars->new_var = NULL; | |
699 | return error; | |
700 | } | |
701 | ||
4142ef14 MW |
702 | static struct efivars __efivars; |
703 | ||
1da177e4 LT |
704 | /* |
705 | * For now we register the efi subsystem with the firmware subsystem | |
706 | * and the vars subsystem with the efi subsystem. In the future, it | |
707 | * might make sense to split off the efi subsystem into its own | |
708 | * driver, but for now only efivars will register with it, so just | |
709 | * include it here. | |
710 | */ | |
711 | ||
712 | static int __init | |
713 | efivars_init(void) | |
714 | { | |
715 | efi_status_t status = EFI_NOT_FOUND; | |
716 | efi_guid_t vendor_guid; | |
717 | efi_char16_t *variable_name; | |
1da177e4 | 718 | unsigned long variable_name_size = 1024; |
4142ef14 | 719 | struct efivars *efivars = &__efivars; |
334c6307 | 720 | int error = 0; |
1da177e4 LT |
721 | |
722 | if (!efi_enabled) | |
723 | return -ENODEV; | |
724 | ||
9c215384 | 725 | variable_name = kzalloc(variable_name_size, GFP_KERNEL); |
1da177e4 LT |
726 | if (!variable_name) { |
727 | printk(KERN_ERR "efivars: Memory allocation failed.\n"); | |
728 | return -ENOMEM; | |
729 | } | |
730 | ||
1da177e4 LT |
731 | printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, |
732 | EFIVARS_DATE); | |
733 | ||
bc87d2fe GKH |
734 | /* For now we'll register the efi directory at /sys/firmware/efi */ |
735 | efi_kobj = kobject_create_and_add("efi", firmware_kobj); | |
736 | if (!efi_kobj) { | |
89a07e34 GKH |
737 | printk(KERN_ERR "efivars: Firmware registration failed.\n"); |
738 | error = -ENOMEM; | |
1da177e4 LT |
739 | goto out_free; |
740 | } | |
741 | ||
29422693 MW |
742 | spin_lock_init(&efivars->lock); |
743 | INIT_LIST_HEAD(&efivars->list); | |
744 | ||
745 | efivars->kset = kset_create_and_add("vars", NULL, efi_kobj); | |
746 | if (!efivars->kset) { | |
66ac831e GKH |
747 | printk(KERN_ERR "efivars: Subsystem registration failed.\n"); |
748 | error = -ENOMEM; | |
1da177e4 LT |
749 | goto out_firmware_unregister; |
750 | } | |
751 | ||
752 | /* | |
753 | * Per EFI spec, the maximum storage allocated for both | |
754 | * the variable name and variable data is 1024 bytes. | |
755 | */ | |
756 | ||
757 | do { | |
758 | variable_name_size = 1024; | |
759 | ||
760 | status = efi.get_next_variable(&variable_name_size, | |
761 | variable_name, | |
762 | &vendor_guid); | |
763 | switch (status) { | |
764 | case EFI_SUCCESS: | |
4142ef14 MW |
765 | efivar_create_sysfs_entry(efivars, |
766 | variable_name_size, | |
767 | variable_name, | |
768 | &vendor_guid); | |
1da177e4 LT |
769 | break; |
770 | case EFI_NOT_FOUND: | |
771 | break; | |
772 | default: | |
773 | printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n", | |
774 | status); | |
775 | status = EFI_NOT_FOUND; | |
776 | break; | |
777 | } | |
778 | } while (status != EFI_NOT_FOUND); | |
779 | ||
d502fbb0 | 780 | error = create_efivars_bin_attributes(efivars); |
1da177e4 LT |
781 | |
782 | /* Don't forget the systab entry */ | |
bc87d2fe | 783 | error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); |
1da177e4 LT |
784 | if (error) |
785 | printk(KERN_ERR "efivars: Sysfs attribute export failed with error %d.\n", error); | |
786 | else | |
787 | goto out_free; | |
788 | ||
29422693 | 789 | kset_unregister(efivars->kset); |
1da177e4 LT |
790 | |
791 | out_firmware_unregister: | |
c10997f6 | 792 | kobject_put(efi_kobj); |
1da177e4 LT |
793 | |
794 | out_free: | |
795 | kfree(variable_name); | |
796 | ||
797 | return error; | |
798 | } | |
799 | ||
800 | static void __exit | |
801 | efivars_exit(void) | |
802 | { | |
4142ef14 | 803 | struct efivars *efivars = &__efivars; |
496a0fc8 | 804 | struct efivar_entry *entry, *n; |
1da177e4 | 805 | |
29422693 MW |
806 | list_for_each_entry_safe(entry, n, &efivars->list, list) { |
807 | spin_lock(&efivars->lock); | |
496a0fc8 | 808 | list_del(&entry->list); |
29422693 | 809 | spin_unlock(&efivars->lock); |
496a0fc8 MD |
810 | efivar_unregister(entry); |
811 | } | |
d502fbb0 MW |
812 | if (efivars->new_var) |
813 | sysfs_remove_bin_file(&efivars->kset->kobj, efivars->new_var); | |
814 | if (efivars->del_var) | |
815 | sysfs_remove_bin_file(&efivars->kset->kobj, efivars->del_var); | |
816 | kfree(efivars->new_var); | |
817 | kfree(efivars->del_var); | |
29422693 | 818 | kset_unregister(efivars->kset); |
c10997f6 | 819 | kobject_put(efi_kobj); |
1da177e4 LT |
820 | } |
821 | ||
822 | module_init(efivars_init); | |
823 | module_exit(efivars_exit); | |
824 |