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> |
5ee9c198 | 81 | #include <linux/pstore.h> |
47f531e8 | 82 | #include <linux/ctype.h> |
1da177e4 | 83 | |
5d9db883 MG |
84 | #include <linux/fs.h> |
85 | #include <linux/ramfs.h> | |
86 | #include <linux/pagemap.h> | |
87 | ||
1da177e4 LT |
88 | #include <asm/uaccess.h> |
89 | ||
90 | #define EFIVARS_VERSION "0.08" | |
91 | #define EFIVARS_DATE "2004-May-17" | |
92 | ||
93 | MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>"); | |
94 | MODULE_DESCRIPTION("sysfs interface to EFI Variables"); | |
95 | MODULE_LICENSE("GPL"); | |
96 | MODULE_VERSION(EFIVARS_VERSION); | |
97 | ||
5ee9c198 MG |
98 | #define DUMP_NAME_LEN 52 |
99 | ||
e14ab23d MF |
100 | static LIST_HEAD(efivarfs_list); |
101 | static LIST_HEAD(efivar_sysfs_list); | |
5ee9c198 | 102 | |
ec0971ba | 103 | static bool efivars_pstore_disable = |
ca0ba26f | 104 | IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE); |
ec0971ba SF |
105 | |
106 | module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644); | |
107 | ||
1da177e4 LT |
108 | struct efivar_attribute { |
109 | struct attribute attr; | |
110 | ssize_t (*show) (struct efivar_entry *entry, char *buf); | |
111 | ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count); | |
112 | }; | |
113 | ||
4423d779 MF |
114 | /* Private pointer to registered efivars */ |
115 | static struct efivars *__efivars; | |
5d9db883 | 116 | |
7644c16c MW |
117 | #define PSTORE_EFI_ATTRIBUTES \ |
118 | (EFI_VARIABLE_NON_VOLATILE | \ | |
119 | EFI_VARIABLE_BOOTSERVICE_ACCESS | \ | |
120 | EFI_VARIABLE_RUNTIME_ACCESS) | |
1da177e4 | 121 | |
e14ab23d MF |
122 | static struct kset *efivars_kset; |
123 | ||
124 | static struct bin_attribute *efivars_new_var; | |
125 | static struct bin_attribute *efivars_del_var; | |
126 | ||
1da177e4 LT |
127 | #define EFIVAR_ATTR(_name, _mode, _show, _store) \ |
128 | struct efivar_attribute efivar_attr_##_name = { \ | |
7b595756 | 129 | .attr = {.name = __stringify(_name), .mode = _mode}, \ |
1da177e4 LT |
130 | .show = _show, \ |
131 | .store = _store, \ | |
132 | }; | |
133 | ||
1da177e4 LT |
134 | #define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr) |
135 | #define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj) | |
136 | ||
137 | /* | |
138 | * Prototype for sysfs creation function | |
139 | */ | |
140 | static int | |
e14ab23d | 141 | efivar_create_sysfs_entry(struct efivar_entry *new_var); |
1da177e4 | 142 | |
a93bc0c6 SA |
143 | /* |
144 | * Prototype for workqueue functions updating sysfs entry | |
145 | */ | |
146 | ||
147 | static void efivar_update_sysfs_entries(struct work_struct *); | |
148 | static DECLARE_WORK(efivar_work, efivar_update_sysfs_entries); | |
e971318b | 149 | static bool efivar_wq_enabled = true; |
a93bc0c6 | 150 | |
1da177e4 LT |
151 | /* |
152 | * Return the number of bytes is the length of this string | |
153 | * Note: this is NOT the same as the number of unicode characters | |
154 | */ | |
155 | static inline unsigned long | |
a2940908 | 156 | utf16_strsize(efi_char16_t *data, unsigned long maxlength) |
1da177e4 | 157 | { |
a2940908 | 158 | return utf16_strnlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t); |
1da177e4 LT |
159 | } |
160 | ||
828aa1f0 MW |
161 | static inline int |
162 | utf16_strncmp(const efi_char16_t *a, const efi_char16_t *b, size_t len) | |
163 | { | |
164 | while (1) { | |
165 | if (len == 0) | |
166 | return 0; | |
167 | if (*a < *b) | |
168 | return -1; | |
169 | if (*a > *b) | |
170 | return 1; | |
171 | if (*a == 0) /* implies *b == 0 */ | |
172 | return 0; | |
173 | a++; | |
174 | b++; | |
175 | len--; | |
176 | } | |
177 | } | |
178 | ||
fec6c20b | 179 | static bool |
54b3a4d3 MG |
180 | validate_device_path(struct efi_variable *var, int match, u8 *buffer, |
181 | unsigned long len) | |
fec6c20b MG |
182 | { |
183 | struct efi_generic_dev_path *node; | |
184 | int offset = 0; | |
185 | ||
186 | node = (struct efi_generic_dev_path *)buffer; | |
187 | ||
54b3a4d3 MG |
188 | if (len < sizeof(*node)) |
189 | return false; | |
fec6c20b | 190 | |
54b3a4d3 MG |
191 | while (offset <= len - sizeof(*node) && |
192 | node->length >= sizeof(*node) && | |
193 | node->length <= len - offset) { | |
194 | offset += node->length; | |
fec6c20b MG |
195 | |
196 | if ((node->type == EFI_DEV_END_PATH || | |
197 | node->type == EFI_DEV_END_PATH2) && | |
198 | node->sub_type == EFI_DEV_END_ENTIRE) | |
199 | return true; | |
200 | ||
201 | node = (struct efi_generic_dev_path *)(buffer + offset); | |
202 | } | |
203 | ||
204 | /* | |
205 | * If we're here then either node->length pointed past the end | |
206 | * of the buffer or we reached the end of the buffer without | |
207 | * finding a device path end node. | |
208 | */ | |
209 | return false; | |
210 | } | |
211 | ||
212 | static bool | |
54b3a4d3 MG |
213 | validate_boot_order(struct efi_variable *var, int match, u8 *buffer, |
214 | unsigned long len) | |
fec6c20b MG |
215 | { |
216 | /* An array of 16-bit integers */ | |
217 | if ((len % 2) != 0) | |
218 | return false; | |
219 | ||
220 | return true; | |
221 | } | |
222 | ||
223 | static bool | |
54b3a4d3 MG |
224 | validate_load_option(struct efi_variable *var, int match, u8 *buffer, |
225 | unsigned long len) | |
fec6c20b MG |
226 | { |
227 | u16 filepathlength; | |
54b3a4d3 MG |
228 | int i, desclength = 0, namelen; |
229 | ||
230 | namelen = utf16_strnlen(var->VariableName, sizeof(var->VariableName)); | |
fec6c20b MG |
231 | |
232 | /* Either "Boot" or "Driver" followed by four digits of hex */ | |
233 | for (i = match; i < match+4; i++) { | |
54b3a4d3 MG |
234 | if (var->VariableName[i] > 127 || |
235 | hex_to_bin(var->VariableName[i] & 0xff) < 0) | |
fec6c20b MG |
236 | return true; |
237 | } | |
238 | ||
54b3a4d3 MG |
239 | /* Reject it if there's 4 digits of hex and then further content */ |
240 | if (namelen > match + 4) | |
241 | return false; | |
242 | ||
243 | /* A valid entry must be at least 8 bytes */ | |
244 | if (len < 8) | |
fec6c20b MG |
245 | return false; |
246 | ||
247 | filepathlength = buffer[4] | buffer[5] << 8; | |
248 | ||
249 | /* | |
250 | * There's no stored length for the description, so it has to be | |
251 | * found by hand | |
252 | */ | |
54b3a4d3 | 253 | desclength = utf16_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2; |
fec6c20b MG |
254 | |
255 | /* Each boot entry must have a descriptor */ | |
256 | if (!desclength) | |
257 | return false; | |
258 | ||
259 | /* | |
260 | * If the sum of the length of the description, the claimed filepath | |
261 | * length and the original header are greater than the length of the | |
262 | * variable, it's malformed | |
263 | */ | |
264 | if ((desclength + filepathlength + 6) > len) | |
265 | return false; | |
266 | ||
267 | /* | |
268 | * And, finally, check the filepath | |
269 | */ | |
270 | return validate_device_path(var, match, buffer + desclength + 6, | |
271 | filepathlength); | |
272 | } | |
273 | ||
274 | static bool | |
54b3a4d3 MG |
275 | validate_uint16(struct efi_variable *var, int match, u8 *buffer, |
276 | unsigned long len) | |
fec6c20b MG |
277 | { |
278 | /* A single 16-bit integer */ | |
279 | if (len != 2) | |
280 | return false; | |
281 | ||
282 | return true; | |
283 | } | |
284 | ||
285 | static bool | |
54b3a4d3 MG |
286 | validate_ascii_string(struct efi_variable *var, int match, u8 *buffer, |
287 | unsigned long len) | |
fec6c20b MG |
288 | { |
289 | int i; | |
290 | ||
291 | for (i = 0; i < len; i++) { | |
292 | if (buffer[i] > 127) | |
293 | return false; | |
294 | ||
295 | if (buffer[i] == 0) | |
296 | return true; | |
297 | } | |
298 | ||
299 | return false; | |
300 | } | |
301 | ||
302 | struct variable_validate { | |
303 | char *name; | |
304 | bool (*validate)(struct efi_variable *var, int match, u8 *data, | |
54b3a4d3 | 305 | unsigned long len); |
fec6c20b MG |
306 | }; |
307 | ||
308 | static const struct variable_validate variable_validate[] = { | |
309 | { "BootNext", validate_uint16 }, | |
310 | { "BootOrder", validate_boot_order }, | |
311 | { "DriverOrder", validate_boot_order }, | |
312 | { "Boot*", validate_load_option }, | |
313 | { "Driver*", validate_load_option }, | |
314 | { "ConIn", validate_device_path }, | |
315 | { "ConInDev", validate_device_path }, | |
316 | { "ConOut", validate_device_path }, | |
317 | { "ConOutDev", validate_device_path }, | |
318 | { "ErrOut", validate_device_path }, | |
319 | { "ErrOutDev", validate_device_path }, | |
320 | { "Timeout", validate_uint16 }, | |
321 | { "Lang", validate_ascii_string }, | |
322 | { "PlatformLang", validate_ascii_string }, | |
323 | { "", NULL }, | |
324 | }; | |
325 | ||
e14ab23d MF |
326 | bool |
327 | efivar_validate(struct efi_variable *var, u8 *data, unsigned long len) | |
fec6c20b MG |
328 | { |
329 | int i; | |
330 | u16 *unicode_name = var->VariableName; | |
331 | ||
332 | for (i = 0; variable_validate[i].validate != NULL; i++) { | |
333 | const char *name = variable_validate[i].name; | |
334 | int match; | |
335 | ||
336 | for (match = 0; ; match++) { | |
337 | char c = name[match]; | |
338 | u16 u = unicode_name[match]; | |
339 | ||
340 | /* All special variables are plain ascii */ | |
341 | if (u > 127) | |
342 | return true; | |
343 | ||
344 | /* Wildcard in the matching name means we've matched */ | |
345 | if (c == '*') | |
346 | return variable_validate[i].validate(var, | |
347 | match, data, len); | |
348 | ||
349 | /* Case sensitive match */ | |
350 | if (c != u) | |
351 | break; | |
352 | ||
353 | /* Reached the end of the string while matching */ | |
354 | if (!c) | |
355 | return variable_validate[i].validate(var, | |
356 | match, data, len); | |
357 | } | |
358 | } | |
359 | ||
360 | return true; | |
361 | } | |
e14ab23d | 362 | EXPORT_SYMBOL_GPL(efivar_validate); |
fec6c20b | 363 | |
1da177e4 | 364 | static efi_status_t |
e14ab23d | 365 | check_var_size(u32 attributes, unsigned long size) |
68d92986 MG |
366 | { |
367 | u64 storage_size, remaining_size, max_size; | |
368 | efi_status_t status; | |
e14ab23d | 369 | const struct efivar_operations *fops = __efivars->ops; |
68d92986 | 370 | |
e14ab23d | 371 | if (!fops->query_variable_info) |
68d92986 MG |
372 | return EFI_UNSUPPORTED; |
373 | ||
374 | status = fops->query_variable_info(attributes, &storage_size, | |
375 | &remaining_size, &max_size); | |
376 | ||
377 | if (status != EFI_SUCCESS) | |
378 | return status; | |
379 | ||
380 | if (!storage_size || size > remaining_size || size > max_size || | |
381 | (remaining_size - size) < (storage_size / 2)) | |
382 | return EFI_OUT_OF_RESOURCES; | |
383 | ||
384 | return status; | |
385 | } | |
386 | ||
1da177e4 LT |
387 | static ssize_t |
388 | efivar_guid_read(struct efivar_entry *entry, char *buf) | |
389 | { | |
390 | struct efi_variable *var = &entry->var; | |
391 | char *str = buf; | |
392 | ||
393 | if (!entry || !buf) | |
394 | return 0; | |
395 | ||
396 | efi_guid_unparse(&var->VendorGuid, str); | |
397 | str += strlen(str); | |
398 | str += sprintf(str, "\n"); | |
399 | ||
400 | return str - buf; | |
401 | } | |
402 | ||
403 | static ssize_t | |
404 | efivar_attr_read(struct efivar_entry *entry, char *buf) | |
405 | { | |
406 | struct efi_variable *var = &entry->var; | |
407 | char *str = buf; | |
1da177e4 LT |
408 | |
409 | if (!entry || !buf) | |
410 | return -EINVAL; | |
411 | ||
e14ab23d MF |
412 | var->DataSize = 1024; |
413 | if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) | |
1da177e4 LT |
414 | return -EIO; |
415 | ||
70839090 | 416 | if (var->Attributes & EFI_VARIABLE_NON_VOLATILE) |
1da177e4 | 417 | str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n"); |
70839090 | 418 | if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS) |
1da177e4 | 419 | str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n"); |
70839090 | 420 | if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS) |
1da177e4 | 421 | str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n"); |
70839090 KA |
422 | if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) |
423 | str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n"); | |
424 | if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) | |
425 | str += sprintf(str, | |
426 | "EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n"); | |
427 | if (var->Attributes & | |
428 | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) | |
429 | str += sprintf(str, | |
430 | "EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n"); | |
431 | if (var->Attributes & EFI_VARIABLE_APPEND_WRITE) | |
432 | str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n"); | |
1da177e4 LT |
433 | return str - buf; |
434 | } | |
435 | ||
436 | static ssize_t | |
437 | efivar_size_read(struct efivar_entry *entry, char *buf) | |
438 | { | |
439 | struct efi_variable *var = &entry->var; | |
440 | char *str = buf; | |
1da177e4 LT |
441 | |
442 | if (!entry || !buf) | |
443 | return -EINVAL; | |
444 | ||
e14ab23d MF |
445 | var->DataSize = 1024; |
446 | if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) | |
1da177e4 LT |
447 | return -EIO; |
448 | ||
449 | str += sprintf(str, "0x%lx\n", var->DataSize); | |
450 | return str - buf; | |
451 | } | |
452 | ||
453 | static ssize_t | |
454 | efivar_data_read(struct efivar_entry *entry, char *buf) | |
455 | { | |
456 | struct efi_variable *var = &entry->var; | |
1da177e4 LT |
457 | |
458 | if (!entry || !buf) | |
459 | return -EINVAL; | |
460 | ||
e14ab23d MF |
461 | var->DataSize = 1024; |
462 | if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) | |
1da177e4 LT |
463 | return -EIO; |
464 | ||
465 | memcpy(buf, var->Data, var->DataSize); | |
466 | return var->DataSize; | |
467 | } | |
468 | /* | |
469 | * We allow each variable to be edited via rewriting the | |
470 | * entire efi variable structure. | |
471 | */ | |
472 | static ssize_t | |
473 | efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) | |
474 | { | |
475 | struct efi_variable *new_var, *var = &entry->var; | |
e14ab23d | 476 | int err; |
1da177e4 LT |
477 | |
478 | if (count != sizeof(struct efi_variable)) | |
479 | return -EINVAL; | |
480 | ||
481 | new_var = (struct efi_variable *)buf; | |
482 | /* | |
483 | * If only updating the variable data, then the name | |
484 | * and guid should remain the same | |
485 | */ | |
486 | if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) || | |
487 | efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) { | |
488 | printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n"); | |
489 | return -EINVAL; | |
490 | } | |
491 | ||
492 | if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){ | |
493 | printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n"); | |
494 | return -EINVAL; | |
495 | } | |
496 | ||
fec6c20b | 497 | if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || |
e14ab23d | 498 | efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { |
fec6c20b MG |
499 | printk(KERN_ERR "efivars: Malformed variable content\n"); |
500 | return -EINVAL; | |
501 | } | |
502 | ||
e14ab23d | 503 | memcpy(&entry->var, new_var, count); |
1da177e4 | 504 | |
e14ab23d MF |
505 | err = efivar_entry_set(entry, new_var->Attributes, |
506 | new_var->DataSize, new_var->Data, false); | |
507 | if (err) { | |
508 | printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err); | |
1da177e4 LT |
509 | return -EIO; |
510 | } | |
511 | ||
1da177e4 LT |
512 | return count; |
513 | } | |
514 | ||
515 | static ssize_t | |
516 | efivar_show_raw(struct efivar_entry *entry, char *buf) | |
517 | { | |
518 | struct efi_variable *var = &entry->var; | |
1da177e4 LT |
519 | |
520 | if (!entry || !buf) | |
521 | return 0; | |
522 | ||
e14ab23d MF |
523 | var->DataSize = 1024; |
524 | if (efivar_entry_get(entry, &entry->var.Attributes, | |
525 | &entry->var.DataSize, entry->var.Data)) | |
1da177e4 LT |
526 | return -EIO; |
527 | ||
528 | memcpy(buf, var, sizeof(*var)); | |
e14ab23d | 529 | |
1da177e4 LT |
530 | return sizeof(*var); |
531 | } | |
532 | ||
533 | /* | |
534 | * Generic read/write functions that call the specific functions of | |
70f23fd6 | 535 | * the attributes... |
1da177e4 LT |
536 | */ |
537 | static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr, | |
538 | char *buf) | |
539 | { | |
540 | struct efivar_entry *var = to_efivar_entry(kobj); | |
541 | struct efivar_attribute *efivar_attr = to_efivar_attr(attr); | |
70f2817a | 542 | ssize_t ret = -EIO; |
1da177e4 LT |
543 | |
544 | if (!capable(CAP_SYS_ADMIN)) | |
545 | return -EACCES; | |
546 | ||
547 | if (efivar_attr->show) { | |
548 | ret = efivar_attr->show(var, buf); | |
549 | } | |
550 | return ret; | |
551 | } | |
552 | ||
553 | static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr, | |
554 | const char *buf, size_t count) | |
555 | { | |
556 | struct efivar_entry *var = to_efivar_entry(kobj); | |
557 | struct efivar_attribute *efivar_attr = to_efivar_attr(attr); | |
70f2817a | 558 | ssize_t ret = -EIO; |
1da177e4 LT |
559 | |
560 | if (!capable(CAP_SYS_ADMIN)) | |
561 | return -EACCES; | |
562 | ||
563 | if (efivar_attr->store) | |
564 | ret = efivar_attr->store(var, buf, count); | |
565 | ||
566 | return ret; | |
567 | } | |
568 | ||
52cf25d0 | 569 | static const struct sysfs_ops efivar_attr_ops = { |
1da177e4 LT |
570 | .show = efivar_attr_show, |
571 | .store = efivar_attr_store, | |
572 | }; | |
573 | ||
574 | static void efivar_release(struct kobject *kobj) | |
575 | { | |
576 | struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj); | |
1da177e4 LT |
577 | kfree(var); |
578 | } | |
579 | ||
580 | static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL); | |
581 | static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL); | |
582 | static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL); | |
583 | static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL); | |
584 | static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw); | |
585 | ||
586 | static struct attribute *def_attrs[] = { | |
587 | &efivar_attr_guid.attr, | |
588 | &efivar_attr_size.attr, | |
589 | &efivar_attr_attributes.attr, | |
590 | &efivar_attr_data.attr, | |
591 | &efivar_attr_raw_var.attr, | |
592 | NULL, | |
593 | }; | |
594 | ||
e89a4116 | 595 | static struct kobj_type efivar_ktype = { |
1da177e4 LT |
596 | .release = efivar_release, |
597 | .sysfs_ops = &efivar_attr_ops, | |
598 | .default_attrs = def_attrs, | |
599 | }; | |
600 | ||
1da177e4 LT |
601 | static inline void |
602 | efivar_unregister(struct efivar_entry *var) | |
603 | { | |
c10997f6 | 604 | kobject_put(&var->kobj); |
1da177e4 LT |
605 | } |
606 | ||
5d9db883 MG |
607 | static int efivarfs_file_open(struct inode *inode, struct file *file) |
608 | { | |
609 | file->private_data = inode->i_private; | |
610 | return 0; | |
611 | } | |
612 | ||
7253eaba MF |
613 | static int efi_status_to_err(efi_status_t status) |
614 | { | |
615 | int err; | |
616 | ||
617 | switch (status) { | |
e14ab23d MF |
618 | case EFI_SUCCESS: |
619 | err = 0; | |
620 | break; | |
7253eaba MF |
621 | case EFI_INVALID_PARAMETER: |
622 | err = -EINVAL; | |
623 | break; | |
624 | case EFI_OUT_OF_RESOURCES: | |
625 | err = -ENOSPC; | |
626 | break; | |
627 | case EFI_DEVICE_ERROR: | |
628 | err = -EIO; | |
629 | break; | |
630 | case EFI_WRITE_PROTECTED: | |
631 | err = -EROFS; | |
632 | break; | |
633 | case EFI_SECURITY_VIOLATION: | |
634 | err = -EACCES; | |
635 | break; | |
636 | case EFI_NOT_FOUND: | |
e14ab23d | 637 | err = -ENOENT; |
7253eaba MF |
638 | break; |
639 | default: | |
640 | err = -EINVAL; | |
641 | } | |
642 | ||
643 | return err; | |
644 | } | |
645 | ||
5d9db883 MG |
646 | static ssize_t efivarfs_file_write(struct file *file, |
647 | const char __user *userbuf, size_t count, loff_t *ppos) | |
648 | { | |
649 | struct efivar_entry *var = file->private_data; | |
5d9db883 MG |
650 | void *data; |
651 | u32 attributes; | |
652 | struct inode *inode = file->f_mapping->host; | |
07b1c5bc | 653 | unsigned long datasize = count - sizeof(attributes); |
cfcf2f11 | 654 | ssize_t bytes = 0; |
e14ab23d | 655 | bool set = false; |
5d9db883 MG |
656 | |
657 | if (count < sizeof(attributes)) | |
658 | return -EINVAL; | |
659 | ||
89d16665 MF |
660 | if (copy_from_user(&attributes, userbuf, sizeof(attributes))) |
661 | return -EFAULT; | |
5d9db883 | 662 | |
89d16665 MF |
663 | if (attributes & ~(EFI_VARIABLE_MASK)) |
664 | return -EINVAL; | |
5d9db883 | 665 | |
89d16665 MF |
666 | data = kmalloc(datasize, GFP_KERNEL); |
667 | if (!data) | |
668 | return -ENOMEM; | |
669 | ||
5d9db883 | 670 | if (copy_from_user(data, userbuf + sizeof(attributes), datasize)) { |
cfcf2f11 | 671 | bytes = -EFAULT; |
5d9db883 MG |
672 | goto out; |
673 | } | |
674 | ||
e14ab23d MF |
675 | bytes = efivar_entry_set_get_size(var, attributes, &datasize, |
676 | data, &set); | |
677 | if (!set && bytes) | |
5d9db883 | 678 | goto out; |
cfcf2f11 | 679 | |
e14ab23d | 680 | if (!bytes) { |
0c542edd | 681 | mutex_lock(&inode->i_mutex); |
e14ab23d | 682 | i_size_write(inode, datasize + sizeof(attributes)); |
0c542edd | 683 | mutex_unlock(&inode->i_mutex); |
e14ab23d | 684 | } else if (bytes == -ENOENT) { |
0c542edd | 685 | drop_nlink(inode); |
791eb564 | 686 | d_delete(file->f_dentry); |
0c542edd | 687 | dput(file->f_dentry); |
e14ab23d | 688 | } else |
0c542edd | 689 | pr_warn("efivarfs: inconsistent EFI variable implementation? " |
e14ab23d MF |
690 | "status=%zu\n", bytes); |
691 | ||
692 | bytes = count; | |
0c542edd | 693 | |
5d9db883 MG |
694 | out: |
695 | kfree(data); | |
696 | ||
cfcf2f11 | 697 | return bytes; |
5d9db883 MG |
698 | } |
699 | ||
700 | static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf, | |
701 | size_t count, loff_t *ppos) | |
702 | { | |
703 | struct efivar_entry *var = file->private_data; | |
5d9db883 MG |
704 | unsigned long datasize = 0; |
705 | u32 attributes; | |
706 | void *data; | |
d142df03 | 707 | ssize_t size = 0; |
e14ab23d | 708 | int err; |
5d9db883 | 709 | |
e14ab23d MF |
710 | err = efivar_entry_size(var, &datasize); |
711 | if (err) | |
712 | return err; | |
5d9db883 | 713 | |
d2923841 | 714 | data = kmalloc(datasize + sizeof(attributes), GFP_KERNEL); |
5d9db883 MG |
715 | |
716 | if (!data) | |
7253eaba | 717 | return -ENOMEM; |
5d9db883 | 718 | |
e14ab23d MF |
719 | size = efivar_entry_get(var, &attributes, &datasize, |
720 | data + sizeof(attributes)); | |
721 | if (size) | |
d142df03 | 722 | goto out_free; |
5d9db883 | 723 | |
d2923841 | 724 | memcpy(data, &attributes, sizeof(attributes)); |
5d9db883 | 725 | size = simple_read_from_buffer(userbuf, count, ppos, |
d2923841 | 726 | data, datasize + sizeof(attributes)); |
d142df03 | 727 | out_free: |
5d9db883 MG |
728 | kfree(data); |
729 | ||
730 | return size; | |
731 | } | |
732 | ||
733 | static void efivarfs_evict_inode(struct inode *inode) | |
734 | { | |
735 | clear_inode(inode); | |
736 | } | |
737 | ||
738 | static const struct super_operations efivarfs_ops = { | |
739 | .statfs = simple_statfs, | |
740 | .drop_inode = generic_delete_inode, | |
741 | .evict_inode = efivarfs_evict_inode, | |
742 | .show_options = generic_show_options, | |
743 | }; | |
744 | ||
745 | static struct super_block *efivarfs_sb; | |
746 | ||
747 | static const struct inode_operations efivarfs_dir_inode_operations; | |
748 | ||
749 | static const struct file_operations efivarfs_file_operations = { | |
750 | .open = efivarfs_file_open, | |
751 | .read = efivarfs_file_read, | |
752 | .write = efivarfs_file_write, | |
753 | .llseek = no_llseek, | |
754 | }; | |
755 | ||
756 | static struct inode *efivarfs_get_inode(struct super_block *sb, | |
757 | const struct inode *dir, int mode, dev_t dev) | |
758 | { | |
759 | struct inode *inode = new_inode(sb); | |
760 | ||
761 | if (inode) { | |
762 | inode->i_ino = get_next_ino(); | |
5d9db883 MG |
763 | inode->i_mode = mode; |
764 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
765 | switch (mode & S_IFMT) { | |
766 | case S_IFREG: | |
767 | inode->i_fop = &efivarfs_file_operations; | |
768 | break; | |
769 | case S_IFDIR: | |
770 | inode->i_op = &efivarfs_dir_inode_operations; | |
771 | inode->i_fop = &simple_dir_operations; | |
772 | inc_nlink(inode); | |
773 | break; | |
774 | } | |
775 | } | |
776 | return inode; | |
777 | } | |
778 | ||
47f531e8 MF |
779 | /* |
780 | * Return true if 'str' is a valid efivarfs filename of the form, | |
781 | * | |
782 | * VariableName-12345678-1234-1234-1234-1234567891bc | |
783 | */ | |
784 | static bool efivarfs_valid_name(const char *str, int len) | |
785 | { | |
e14ab23d | 786 | static const char dashes[EFI_VARIABLE_GUID_LEN] = { |
47f531e8 MF |
787 | [8] = 1, [13] = 1, [18] = 1, [23] = 1 |
788 | }; | |
e14ab23d | 789 | const char *s = str + len - EFI_VARIABLE_GUID_LEN; |
47f531e8 MF |
790 | int i; |
791 | ||
792 | /* | |
793 | * We need a GUID, plus at least one letter for the variable name, | |
794 | * plus the '-' separator | |
795 | */ | |
e14ab23d | 796 | if (len < EFI_VARIABLE_GUID_LEN + 2) |
47f531e8 MF |
797 | return false; |
798 | ||
123abd76 MF |
799 | /* GUID must be preceded by a '-' */ |
800 | if (*(s - 1) != '-') | |
47f531e8 MF |
801 | return false; |
802 | ||
803 | /* | |
804 | * Validate that 's' is of the correct format, e.g. | |
805 | * | |
806 | * 12345678-1234-1234-1234-123456789abc | |
807 | */ | |
e14ab23d | 808 | for (i = 0; i < EFI_VARIABLE_GUID_LEN; i++) { |
47f531e8 MF |
809 | if (dashes[i]) { |
810 | if (*s++ != '-') | |
811 | return false; | |
812 | } else { | |
813 | if (!isxdigit(*s++)) | |
814 | return false; | |
815 | } | |
816 | } | |
817 | ||
818 | return true; | |
819 | } | |
820 | ||
5d9db883 MG |
821 | static void efivarfs_hex_to_guid(const char *str, efi_guid_t *guid) |
822 | { | |
823 | guid->b[0] = hex_to_bin(str[6]) << 4 | hex_to_bin(str[7]); | |
824 | guid->b[1] = hex_to_bin(str[4]) << 4 | hex_to_bin(str[5]); | |
825 | guid->b[2] = hex_to_bin(str[2]) << 4 | hex_to_bin(str[3]); | |
826 | guid->b[3] = hex_to_bin(str[0]) << 4 | hex_to_bin(str[1]); | |
827 | guid->b[4] = hex_to_bin(str[11]) << 4 | hex_to_bin(str[12]); | |
828 | guid->b[5] = hex_to_bin(str[9]) << 4 | hex_to_bin(str[10]); | |
829 | guid->b[6] = hex_to_bin(str[16]) << 4 | hex_to_bin(str[17]); | |
830 | guid->b[7] = hex_to_bin(str[14]) << 4 | hex_to_bin(str[15]); | |
831 | guid->b[8] = hex_to_bin(str[19]) << 4 | hex_to_bin(str[20]); | |
832 | guid->b[9] = hex_to_bin(str[21]) << 4 | hex_to_bin(str[22]); | |
833 | guid->b[10] = hex_to_bin(str[24]) << 4 | hex_to_bin(str[25]); | |
834 | guid->b[11] = hex_to_bin(str[26]) << 4 | hex_to_bin(str[27]); | |
835 | guid->b[12] = hex_to_bin(str[28]) << 4 | hex_to_bin(str[29]); | |
836 | guid->b[13] = hex_to_bin(str[30]) << 4 | hex_to_bin(str[31]); | |
837 | guid->b[14] = hex_to_bin(str[32]) << 4 | hex_to_bin(str[33]); | |
838 | guid->b[15] = hex_to_bin(str[34]) << 4 | hex_to_bin(str[35]); | |
839 | } | |
840 | ||
841 | static int efivarfs_create(struct inode *dir, struct dentry *dentry, | |
842 | umode_t mode, bool excl) | |
843 | { | |
45a937a8 | 844 | struct inode *inode; |
5d9db883 MG |
845 | struct efivar_entry *var; |
846 | int namelen, i = 0, err = 0; | |
847 | ||
47f531e8 | 848 | if (!efivarfs_valid_name(dentry->d_name.name, dentry->d_name.len)) |
5d9db883 MG |
849 | return -EINVAL; |
850 | ||
45a937a8 | 851 | inode = efivarfs_get_inode(dir->i_sb, dir, mode, 0); |
5d9db883 | 852 | if (!inode) |
aeeaa8d4 | 853 | return -ENOMEM; |
5d9db883 MG |
854 | |
855 | var = kzalloc(sizeof(struct efivar_entry), GFP_KERNEL); | |
45a937a8 AW |
856 | if (!var) { |
857 | err = -ENOMEM; | |
858 | goto out; | |
859 | } | |
5d9db883 | 860 | |
310ad754 | 861 | /* length of the variable name itself: remove GUID and separator */ |
e14ab23d | 862 | namelen = dentry->d_name.len - EFI_VARIABLE_GUID_LEN - 1; |
5d9db883 MG |
863 | |
864 | efivarfs_hex_to_guid(dentry->d_name.name + namelen + 1, | |
865 | &var->var.VendorGuid); | |
866 | ||
867 | for (i = 0; i < namelen; i++) | |
868 | var->var.VariableName[i] = dentry->d_name.name[i]; | |
869 | ||
870 | var->var.VariableName[i] = '\0'; | |
871 | ||
872 | inode->i_private = var; | |
5d9db883 | 873 | |
e14ab23d | 874 | efivar_entry_add(var, &efivarfs_list); |
5d9db883 MG |
875 | d_instantiate(dentry, inode); |
876 | dget(dentry); | |
877 | out: | |
45a937a8 | 878 | if (err) { |
5d9db883 | 879 | kfree(var); |
45a937a8 AW |
880 | iput(inode); |
881 | } | |
5d9db883 MG |
882 | return err; |
883 | } | |
884 | ||
885 | static int efivarfs_unlink(struct inode *dir, struct dentry *dentry) | |
886 | { | |
887 | struct efivar_entry *var = dentry->d_inode->i_private; | |
5d9db883 | 888 | |
e14ab23d MF |
889 | if (efivar_entry_delete(var)) |
890 | return -EINVAL; | |
5d9db883 | 891 | |
e14ab23d MF |
892 | drop_nlink(dentry->d_inode); |
893 | dput(dentry); | |
894 | return 0; | |
5d9db883 MG |
895 | }; |
896 | ||
da27a243 MF |
897 | /* |
898 | * Compare two efivarfs file names. | |
899 | * | |
900 | * An efivarfs filename is composed of two parts, | |
901 | * | |
902 | * 1. A case-sensitive variable name | |
903 | * 2. A case-insensitive GUID | |
904 | * | |
905 | * So we need to perform a case-sensitive match on part 1 and a | |
906 | * case-insensitive match on part 2. | |
907 | */ | |
908 | static int efivarfs_d_compare(const struct dentry *parent, const struct inode *pinode, | |
909 | const struct dentry *dentry, const struct inode *inode, | |
910 | unsigned int len, const char *str, | |
911 | const struct qstr *name) | |
912 | { | |
e14ab23d | 913 | int guid = len - EFI_VARIABLE_GUID_LEN; |
da27a243 MF |
914 | |
915 | if (name->len != len) | |
916 | return 1; | |
917 | ||
918 | /* Case-sensitive compare for the variable name */ | |
919 | if (memcmp(str, name->name, guid)) | |
920 | return 1; | |
921 | ||
922 | /* Case-insensitive compare for the GUID */ | |
e14ab23d | 923 | return strncasecmp(name->name + guid, str + guid, EFI_VARIABLE_GUID_LEN); |
da27a243 MF |
924 | } |
925 | ||
926 | static int efivarfs_d_hash(const struct dentry *dentry, | |
927 | const struct inode *inode, struct qstr *qstr) | |
928 | { | |
929 | unsigned long hash = init_name_hash(); | |
930 | const unsigned char *s = qstr->name; | |
931 | unsigned int len = qstr->len; | |
932 | ||
933 | if (!efivarfs_valid_name(s, len)) | |
934 | return -EINVAL; | |
935 | ||
e14ab23d | 936 | while (len-- > EFI_VARIABLE_GUID_LEN) |
da27a243 MF |
937 | hash = partial_name_hash(*s++, hash); |
938 | ||
939 | /* GUID is case-insensitive. */ | |
940 | while (len--) | |
941 | hash = partial_name_hash(tolower(*s++), hash); | |
942 | ||
943 | qstr->hash = end_name_hash(hash); | |
944 | return 0; | |
945 | } | |
946 | ||
947 | /* | |
948 | * Retaining negative dentries for an in-memory filesystem just wastes | |
949 | * memory and lookup time: arrange for them to be deleted immediately. | |
950 | */ | |
951 | static int efivarfs_delete_dentry(const struct dentry *dentry) | |
952 | { | |
953 | return 1; | |
954 | } | |
955 | ||
956 | static struct dentry_operations efivarfs_d_ops = { | |
957 | .d_compare = efivarfs_d_compare, | |
958 | .d_hash = efivarfs_d_hash, | |
959 | .d_delete = efivarfs_delete_dentry, | |
960 | }; | |
961 | ||
962 | static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name) | |
963 | { | |
feff5dc4 | 964 | struct dentry *d; |
da27a243 | 965 | struct qstr q; |
feff5dc4 | 966 | int err; |
da27a243 MF |
967 | |
968 | q.name = name; | |
969 | q.len = strlen(name); | |
970 | ||
feff5dc4 MF |
971 | err = efivarfs_d_hash(NULL, NULL, &q); |
972 | if (err) | |
973 | return ERR_PTR(err); | |
974 | ||
975 | d = d_alloc(parent, &q); | |
976 | if (d) | |
977 | return d; | |
da27a243 | 978 | |
feff5dc4 | 979 | return ERR_PTR(-ENOMEM); |
da27a243 MF |
980 | } |
981 | ||
e14ab23d MF |
982 | static int efivarfs_callback(efi_char16_t *name16, efi_guid_t vendor, |
983 | unsigned long name_size, void *data) | |
5d9db883 | 984 | { |
e14ab23d MF |
985 | struct super_block *sb = (struct super_block *)data; |
986 | struct efivar_entry *entry; | |
5d9db883 | 987 | struct inode *inode = NULL; |
e14ab23d MF |
988 | struct dentry *dentry, *root = sb->s_root; |
989 | unsigned long size = 0; | |
5ba6e291 | 990 | char *name; |
e14ab23d | 991 | int len, i; |
feff5dc4 | 992 | int err = -ENOMEM; |
5d9db883 | 993 | |
e14ab23d MF |
994 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); |
995 | if (!entry) | |
996 | return err; | |
997 | ||
998 | memcpy(entry->var.VariableName, name16, name_size); | |
999 | memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); | |
1000 | ||
1001 | len = utf16_strlen(entry->var.VariableName); | |
1002 | ||
1003 | /* name, plus '-', plus GUID, plus NUL*/ | |
1004 | name = kmalloc(len + 1 + EFI_VARIABLE_GUID_LEN + 1, GFP_KERNEL); | |
1005 | if (!name) | |
1006 | goto fail; | |
1007 | ||
1008 | for (i = 0; i < len; i++) | |
1009 | name[i] = entry->var.VariableName[i] & 0xFF; | |
1010 | ||
1011 | name[len] = '-'; | |
1012 | ||
1013 | efi_guid_unparse(&entry->var.VendorGuid, name + len + 1); | |
1014 | ||
1015 | name[len + EFI_VARIABLE_GUID_LEN+1] = '\0'; | |
1016 | ||
1017 | inode = efivarfs_get_inode(sb, root->d_inode, S_IFREG | 0644, 0); | |
1018 | if (!inode) | |
1019 | goto fail_name; | |
1020 | ||
1021 | dentry = efivarfs_alloc_dentry(root, name); | |
1022 | if (IS_ERR(dentry)) { | |
1023 | err = PTR_ERR(dentry); | |
1024 | goto fail_inode; | |
1025 | } | |
1026 | ||
1027 | /* copied by the above to local storage in the dentry. */ | |
1028 | kfree(name); | |
1029 | ||
1030 | efivar_entry_size(entry, &size); | |
1031 | efivar_entry_add(entry, &efivarfs_list); | |
1032 | ||
1033 | mutex_lock(&inode->i_mutex); | |
1034 | inode->i_private = entry; | |
1035 | i_size_write(inode, size + sizeof(entry->var.Attributes)); | |
1036 | mutex_unlock(&inode->i_mutex); | |
1037 | d_add(dentry, inode); | |
1038 | ||
1039 | return 0; | |
1040 | ||
1041 | fail_inode: | |
1042 | iput(inode); | |
1043 | fail_name: | |
1044 | kfree(name); | |
1045 | fail: | |
1046 | kfree(entry); | |
1047 | return err; | |
1048 | } | |
1049 | ||
1050 | static int efivarfs_destroy(struct efivar_entry *entry, void *data) | |
1051 | { | |
1052 | efivar_entry_remove(entry); | |
1053 | kfree(entry); | |
1054 | return 0; | |
1055 | } | |
1056 | ||
1057 | static int efivarfs_fill_super(struct super_block *sb, void *data, int silent) | |
1058 | { | |
1059 | struct inode *inode = NULL; | |
1060 | struct dentry *root; | |
1061 | int err; | |
1062 | ||
5d9db883 MG |
1063 | efivarfs_sb = sb; |
1064 | ||
1065 | sb->s_maxbytes = MAX_LFS_FILESIZE; | |
1066 | sb->s_blocksize = PAGE_CACHE_SIZE; | |
1067 | sb->s_blocksize_bits = PAGE_CACHE_SHIFT; | |
91716322 | 1068 | sb->s_magic = EFIVARFS_MAGIC; |
5d9db883 | 1069 | sb->s_op = &efivarfs_ops; |
da27a243 | 1070 | sb->s_d_op = &efivarfs_d_ops; |
5d9db883 MG |
1071 | sb->s_time_gran = 1; |
1072 | ||
1073 | inode = efivarfs_get_inode(sb, NULL, S_IFDIR | 0755, 0); | |
5c9b50ab AW |
1074 | if (!inode) |
1075 | return -ENOMEM; | |
5d9db883 MG |
1076 | inode->i_op = &efivarfs_dir_inode_operations; |
1077 | ||
1078 | root = d_make_root(inode); | |
1079 | sb->s_root = root; | |
5c9b50ab AW |
1080 | if (!root) |
1081 | return -ENOMEM; | |
5d9db883 | 1082 | |
e14ab23d | 1083 | INIT_LIST_HEAD(&efivarfs_list); |
5d9db883 | 1084 | |
e14ab23d MF |
1085 | err = efivar_init(efivarfs_callback, (void *)sb, false, |
1086 | true, &efivarfs_list); | |
1087 | if (err) | |
1088 | __efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL); | |
5ba6e291 | 1089 | |
feff5dc4 | 1090 | return err; |
5d9db883 MG |
1091 | } |
1092 | ||
1093 | static struct dentry *efivarfs_mount(struct file_system_type *fs_type, | |
1094 | int flags, const char *dev_name, void *data) | |
1095 | { | |
1096 | return mount_single(fs_type, flags, data, efivarfs_fill_super); | |
1097 | } | |
1098 | ||
1099 | static void efivarfs_kill_sb(struct super_block *sb) | |
1100 | { | |
1101 | kill_litter_super(sb); | |
1102 | efivarfs_sb = NULL; | |
e14ab23d MF |
1103 | |
1104 | /* Remove all entries and destroy */ | |
1105 | __efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL, NULL); | |
5d9db883 MG |
1106 | } |
1107 | ||
1108 | static struct file_system_type efivarfs_type = { | |
1109 | .name = "efivarfs", | |
1110 | .mount = efivarfs_mount, | |
1111 | .kill_sb = efivarfs_kill_sb, | |
1112 | }; | |
7f78e035 | 1113 | MODULE_ALIAS_FS("efivarfs"); |
5d9db883 | 1114 | |
da27a243 MF |
1115 | /* |
1116 | * Handle negative dentry. | |
1117 | */ | |
1118 | static struct dentry *efivarfs_lookup(struct inode *dir, struct dentry *dentry, | |
1119 | unsigned int flags) | |
1120 | { | |
1121 | if (dentry->d_name.len > NAME_MAX) | |
1122 | return ERR_PTR(-ENAMETOOLONG); | |
1123 | d_add(dentry, NULL); | |
1124 | return NULL; | |
1125 | } | |
1126 | ||
5d9db883 | 1127 | static const struct inode_operations efivarfs_dir_inode_operations = { |
da27a243 | 1128 | .lookup = efivarfs_lookup, |
5d9db883 MG |
1129 | .unlink = efivarfs_unlink, |
1130 | .create = efivarfs_create, | |
1131 | }; | |
1132 | ||
ed9dc8ce | 1133 | #ifdef CONFIG_EFI_VARS_PSTORE |
5ee9c198 MG |
1134 | |
1135 | static int efi_pstore_open(struct pstore_info *psi) | |
1136 | { | |
e14ab23d MF |
1137 | efivar_entry_iter_begin(); |
1138 | psi->data = NULL; | |
5ee9c198 MG |
1139 | return 0; |
1140 | } | |
1141 | ||
1142 | static int efi_pstore_close(struct pstore_info *psi) | |
1143 | { | |
e14ab23d MF |
1144 | efivar_entry_iter_end(); |
1145 | psi->data = NULL; | |
5ee9c198 MG |
1146 | return 0; |
1147 | } | |
1148 | ||
e14ab23d MF |
1149 | struct pstore_read_data { |
1150 | u64 *id; | |
1151 | enum pstore_type_id *type; | |
1152 | int *count; | |
1153 | struct timespec *timespec; | |
1154 | char **buf; | |
1155 | }; | |
1156 | ||
1157 | static int efi_pstore_read_func(struct efivar_entry *entry, void *data) | |
5ee9c198 MG |
1158 | { |
1159 | efi_guid_t vendor = LINUX_EFI_CRASH_GUID; | |
e14ab23d | 1160 | struct pstore_read_data *cb_data = data; |
5ee9c198 MG |
1161 | char name[DUMP_NAME_LEN]; |
1162 | int i; | |
755d4fe4 | 1163 | int cnt; |
e14ab23d MF |
1164 | unsigned int part; |
1165 | unsigned long time, size; | |
0f7de85a | 1166 | |
e14ab23d MF |
1167 | if (efi_guidcmp(entry->var.VendorGuid, vendor)) |
1168 | return 0; | |
1169 | ||
1170 | for (i = 0; i < DUMP_NAME_LEN; i++) | |
1171 | name[i] = entry->var.VariableName[i]; | |
1172 | ||
1173 | if (sscanf(name, "dump-type%u-%u-%d-%lu", | |
1174 | cb_data->type, &part, &cnt, &time) == 4) { | |
1175 | *cb_data->id = part; | |
1176 | *cb_data->count = cnt; | |
1177 | cb_data->timespec->tv_sec = time; | |
1178 | cb_data->timespec->tv_nsec = 0; | |
1179 | } else if (sscanf(name, "dump-type%u-%u-%lu", | |
1180 | cb_data->type, &part, &time) == 3) { | |
1181 | /* | |
1182 | * Check if an old format, | |
1183 | * which doesn't support holding | |
1184 | * multiple logs, remains. | |
1185 | */ | |
1186 | *cb_data->id = part; | |
1187 | *cb_data->count = 0; | |
1188 | cb_data->timespec->tv_sec = time; | |
1189 | cb_data->timespec->tv_nsec = 0; | |
1190 | } else | |
1191 | return 0; | |
1192 | ||
1193 | __efivar_entry_size(entry, &size); | |
1194 | *cb_data->buf = kmalloc(size, GFP_KERNEL); | |
1195 | if (*cb_data->buf == NULL) | |
1196 | return -ENOMEM; | |
1197 | memcpy(*cb_data->buf, entry->var.Data, size); | |
1198 | return size; | |
1199 | } | |
1200 | ||
1201 | static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, | |
1202 | int *count, struct timespec *timespec, | |
1203 | char **buf, struct pstore_info *psi) | |
1204 | { | |
1205 | struct pstore_read_data data; | |
1206 | ||
1207 | data.id = id; | |
1208 | data.type = type; | |
1209 | data.count = count; | |
1210 | data.timespec = timespec; | |
1211 | data.buf = buf; | |
1212 | ||
1213 | return __efivar_entry_iter(efi_pstore_read_func, &efivar_sysfs_list, &data, | |
1214 | (struct efivar_entry **)&psi->data); | |
5ee9c198 MG |
1215 | } |
1216 | ||
3d6d8d20 KC |
1217 | static int efi_pstore_write(enum pstore_type_id type, |
1218 | enum kmsg_dump_reason reason, u64 *id, | |
755d4fe4 SA |
1219 | unsigned int part, int count, size_t size, |
1220 | struct pstore_info *psi) | |
5ee9c198 MG |
1221 | { |
1222 | char name[DUMP_NAME_LEN]; | |
5ee9c198 MG |
1223 | efi_char16_t efi_name[DUMP_NAME_LEN]; |
1224 | efi_guid_t vendor = LINUX_EFI_CRASH_GUID; | |
b238b8fa | 1225 | int i, ret = 0; |
d80a361d | 1226 | |
755d4fe4 | 1227 | sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count, |
96480d9c | 1228 | get_seconds()); |
5ee9c198 MG |
1229 | |
1230 | for (i = 0; i < DUMP_NAME_LEN; i++) | |
1231 | efi_name[i] = name[i]; | |
1232 | ||
e14ab23d MF |
1233 | ret = efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES, |
1234 | !pstore_cannot_block_path(reason), | |
1235 | size, psi->buf); | |
5ee9c198 | 1236 | |
e971318b | 1237 | if (reason == KMSG_DUMP_OOPS && efivar_wq_enabled) |
a93bc0c6 | 1238 | schedule_work(&efivar_work); |
5ee9c198 | 1239 | |
b238b8fa CG |
1240 | *id = part; |
1241 | return ret; | |
5ee9c198 MG |
1242 | }; |
1243 | ||
e14ab23d MF |
1244 | struct pstore_erase_data { |
1245 | u64 id; | |
1246 | enum pstore_type_id type; | |
1247 | int count; | |
1248 | struct timespec time; | |
1249 | efi_char16_t *name; | |
1250 | }; | |
1251 | ||
1252 | /* | |
1253 | * Clean up an entry with the same name | |
1254 | */ | |
1255 | static int efi_pstore_erase_func(struct efivar_entry *entry, void *data) | |
5ee9c198 | 1256 | { |
e14ab23d | 1257 | struct pstore_erase_data *ed = data; |
dd230fec | 1258 | efi_guid_t vendor = LINUX_EFI_CRASH_GUID; |
e14ab23d MF |
1259 | efi_char16_t efi_name_old[DUMP_NAME_LEN]; |
1260 | efi_char16_t *efi_name = ed->name; | |
1261 | unsigned long utf16_len = utf16_strlen(ed->name); | |
1262 | char name_old[DUMP_NAME_LEN]; | |
dd230fec SA |
1263 | int i; |
1264 | ||
e14ab23d MF |
1265 | if (efi_guidcmp(entry->var.VendorGuid, vendor)) |
1266 | return 0; | |
dd230fec | 1267 | |
e14ab23d MF |
1268 | if (utf16_strncmp(entry->var.VariableName, |
1269 | efi_name, (size_t)utf16_len)) { | |
1270 | /* | |
1271 | * Check if an old format, which doesn't support | |
1272 | * holding multiple logs, remains. | |
1273 | */ | |
1274 | sprintf(name_old, "dump-type%u-%u-%lu", ed->type, | |
1275 | (unsigned int)ed->id, ed->time.tv_sec); | |
dd230fec | 1276 | |
e14ab23d MF |
1277 | for (i = 0; i < DUMP_NAME_LEN; i++) |
1278 | efi_name_old[i] = name_old[i]; | |
dd230fec | 1279 | |
e14ab23d MF |
1280 | if (utf16_strncmp(entry->var.VariableName, efi_name_old, |
1281 | utf16_strlen(efi_name_old))) | |
1282 | return 0; | |
1283 | } | |
dd230fec | 1284 | |
e14ab23d MF |
1285 | /* found */ |
1286 | __efivar_entry_delete(entry); | |
1287 | return 1; | |
1288 | } | |
f94ec0c0 | 1289 | |
e14ab23d MF |
1290 | static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, |
1291 | struct timespec time, struct pstore_info *psi) | |
1292 | { | |
1293 | struct pstore_erase_data edata; | |
1294 | struct efivar_entry *entry; | |
1295 | char name[DUMP_NAME_LEN]; | |
1296 | efi_char16_t efi_name[DUMP_NAME_LEN]; | |
1297 | int found, i; | |
f94ec0c0 | 1298 | |
e14ab23d MF |
1299 | sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count, |
1300 | time.tv_sec); | |
dd230fec | 1301 | |
e14ab23d MF |
1302 | for (i = 0; i < DUMP_NAME_LEN; i++) |
1303 | efi_name[i] = name[i]; | |
dd230fec | 1304 | |
e14ab23d MF |
1305 | edata.id = id; |
1306 | edata.type = type; | |
1307 | edata.count = count; | |
1308 | edata.time = time; | |
1309 | edata.name = efi_name; | |
dd230fec | 1310 | |
e14ab23d MF |
1311 | efivar_entry_iter_begin(); |
1312 | found = __efivar_entry_iter(efi_pstore_erase_func, &efivar_sysfs_list, &edata, &entry); | |
1313 | efivar_entry_iter_end(); | |
dd230fec SA |
1314 | |
1315 | if (found) | |
e14ab23d | 1316 | efivar_unregister(entry); |
5ee9c198 MG |
1317 | |
1318 | return 0; | |
1319 | } | |
5ee9c198 MG |
1320 | |
1321 | static struct pstore_info efi_pstore_info = { | |
1322 | .owner = THIS_MODULE, | |
1323 | .name = "efi", | |
1324 | .open = efi_pstore_open, | |
1325 | .close = efi_pstore_close, | |
1326 | .read = efi_pstore_read, | |
1327 | .write = efi_pstore_write, | |
1328 | .erase = efi_pstore_erase, | |
1329 | }; | |
1da177e4 | 1330 | |
e14ab23d | 1331 | static void efivar_pstore_register(void) |
ed9dc8ce | 1332 | { |
e14ab23d MF |
1333 | efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL); |
1334 | if (efi_pstore_info.buf) { | |
1335 | efi_pstore_info.bufsize = 1024; | |
1336 | spin_lock_init(&efi_pstore_info.buf_lock); | |
1337 | pstore_register(&efi_pstore_info); | |
ed9dc8ce SF |
1338 | } |
1339 | } | |
1340 | #else | |
e14ab23d | 1341 | static void efivar_pstore_register(void) |
ed9dc8ce SF |
1342 | { |
1343 | return; | |
1344 | } | |
1345 | #endif | |
1346 | ||
2c3c8bea | 1347 | static ssize_t efivar_create(struct file *filp, struct kobject *kobj, |
97fa5bb7 GKH |
1348 | struct bin_attribute *bin_attr, |
1349 | char *buf, loff_t pos, size_t count) | |
1da177e4 LT |
1350 | { |
1351 | struct efi_variable *new_var = (struct efi_variable *)buf; | |
e14ab23d MF |
1352 | struct efivar_entry *new_entry; |
1353 | int err; | |
1da177e4 LT |
1354 | |
1355 | if (!capable(CAP_SYS_ADMIN)) | |
1356 | return -EACCES; | |
1357 | ||
fec6c20b | 1358 | if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || |
e14ab23d | 1359 | efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { |
fec6c20b MG |
1360 | printk(KERN_ERR "efivars: Malformed variable content\n"); |
1361 | return -EINVAL; | |
1362 | } | |
1363 | ||
e14ab23d MF |
1364 | new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL); |
1365 | if (!new_entry) | |
1366 | return -ENOMEM; | |
1da177e4 | 1367 | |
e14ab23d | 1368 | memcpy(&new_entry->var, new_var, sizeof(*new_var)); |
68d92986 | 1369 | |
e14ab23d MF |
1370 | err = efivar_entry_set(new_entry, new_var->Attributes, new_var->DataSize, |
1371 | new_var->Data, &efivar_sysfs_list); | |
1372 | if (err) { | |
1373 | if (err == -EEXIST) | |
1374 | err = -EINVAL; | |
1375 | goto out; | |
68d92986 MG |
1376 | } |
1377 | ||
e14ab23d MF |
1378 | if (efivar_create_sysfs_entry(new_entry)) { |
1379 | printk(KERN_WARNING "efivars: failed to create sysfs entry.\n"); | |
1380 | kfree(new_entry); | |
1da177e4 LT |
1381 | } |
1382 | return count; | |
e14ab23d MF |
1383 | |
1384 | out: | |
1385 | kfree(new_entry); | |
1386 | return err; | |
1da177e4 LT |
1387 | } |
1388 | ||
2c3c8bea | 1389 | static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, |
97fa5bb7 GKH |
1390 | struct bin_attribute *bin_attr, |
1391 | char *buf, loff_t pos, size_t count) | |
1da177e4 LT |
1392 | { |
1393 | struct efi_variable *del_var = (struct efi_variable *)buf; | |
e14ab23d MF |
1394 | struct efivar_entry *entry; |
1395 | int err = 0; | |
1da177e4 LT |
1396 | |
1397 | if (!capable(CAP_SYS_ADMIN)) | |
1398 | return -EACCES; | |
1399 | ||
e14ab23d MF |
1400 | efivar_entry_iter_begin(); |
1401 | entry = efivar_entry_find(del_var->VariableName, del_var->VendorGuid, | |
1402 | &efivar_sysfs_list, true); | |
1403 | if (!entry) | |
1404 | err = -EINVAL; | |
1405 | else if (__efivar_entry_delete(entry)) | |
1406 | err = -EIO; | |
1da177e4 | 1407 | |
e14ab23d | 1408 | efivar_entry_iter_end(); |
1da177e4 | 1409 | |
e14ab23d MF |
1410 | if (err) |
1411 | return err; | |
1da177e4 | 1412 | |
e14ab23d | 1413 | efivar_unregister(entry); |
1da177e4 LT |
1414 | |
1415 | /* It's dead Jim.... */ | |
1416 | return count; | |
1417 | } | |
1418 | ||
e14ab23d MF |
1419 | static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor, |
1420 | struct list_head *head) | |
a93bc0c6 SA |
1421 | { |
1422 | struct efivar_entry *entry, *n; | |
a93bc0c6 SA |
1423 | unsigned long strsize1, strsize2; |
1424 | bool found = false; | |
1425 | ||
1426 | strsize1 = utf16_strsize(variable_name, 1024); | |
e14ab23d | 1427 | list_for_each_entry_safe(entry, n, head, list) { |
a93bc0c6 SA |
1428 | strsize2 = utf16_strsize(entry->var.VariableName, 1024); |
1429 | if (strsize1 == strsize2 && | |
1430 | !memcmp(variable_name, &(entry->var.VariableName), | |
1431 | strsize2) && | |
1432 | !efi_guidcmp(entry->var.VendorGuid, | |
1433 | *vendor)) { | |
1434 | found = true; | |
1435 | break; | |
1436 | } | |
1437 | } | |
1438 | return found; | |
1439 | } | |
1440 | ||
e14ab23d MF |
1441 | static int efivar_update_sysfs_entry(efi_char16_t *name, efi_guid_t vendor, |
1442 | unsigned long name_size, void *data) | |
1443 | { | |
1444 | struct efivar_entry *entry = data; | |
1445 | ||
1446 | if (efivar_entry_find(name, vendor, &efivar_sysfs_list, false)) | |
1447 | return 0; | |
1448 | ||
1449 | memcpy(entry->var.VariableName, name, name_size); | |
1450 | memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); | |
1451 | ||
1452 | return 1; | |
1453 | } | |
1454 | ||
ec50bd32 MF |
1455 | /* |
1456 | * Returns the size of variable_name, in bytes, including the | |
1457 | * terminating NULL character, or variable_name_size if no NULL | |
1458 | * character is found among the first variable_name_size bytes. | |
1459 | */ | |
1460 | static unsigned long var_name_strnsize(efi_char16_t *variable_name, | |
1461 | unsigned long variable_name_size) | |
1462 | { | |
1463 | unsigned long len; | |
1464 | efi_char16_t c; | |
1465 | ||
1466 | /* | |
1467 | * The variable name is, by definition, a NULL-terminated | |
1468 | * string, so make absolutely sure that variable_name_size is | |
1469 | * the value we expect it to be. If not, return the real size. | |
1470 | */ | |
1471 | for (len = 2; len <= variable_name_size; len += sizeof(c)) { | |
1472 | c = variable_name[(len / sizeof(c)) - 1]; | |
1473 | if (!c) | |
1474 | break; | |
1475 | } | |
1476 | ||
1477 | return min(len, variable_name_size); | |
1478 | } | |
1479 | ||
a93bc0c6 SA |
1480 | static void efivar_update_sysfs_entries(struct work_struct *work) |
1481 | { | |
e14ab23d MF |
1482 | struct efivar_entry *entry; |
1483 | int err; | |
1484 | ||
1485 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
1486 | if (!entry) | |
1487 | return; | |
a93bc0c6 SA |
1488 | |
1489 | /* Add new sysfs entries */ | |
1490 | while (1) { | |
e14ab23d | 1491 | memset(entry, 0, sizeof(*entry)); |
a93bc0c6 | 1492 | |
e14ab23d MF |
1493 | err = efivar_init(efivar_update_sysfs_entry, entry, |
1494 | true, false, &efivar_sysfs_list); | |
1495 | if (!err) | |
a93bc0c6 | 1496 | break; |
e14ab23d MF |
1497 | |
1498 | efivar_create_sysfs_entry(entry); | |
a93bc0c6 | 1499 | } |
e14ab23d MF |
1500 | |
1501 | kfree(entry); | |
a93bc0c6 SA |
1502 | } |
1503 | ||
1da177e4 LT |
1504 | /* |
1505 | * Let's not leave out systab information that snuck into | |
1506 | * the efivars driver | |
1507 | */ | |
334c6307 GKH |
1508 | static ssize_t systab_show(struct kobject *kobj, |
1509 | struct kobj_attribute *attr, char *buf) | |
1da177e4 LT |
1510 | { |
1511 | char *str = buf; | |
1512 | ||
334c6307 | 1513 | if (!kobj || !buf) |
1da177e4 LT |
1514 | return -EINVAL; |
1515 | ||
b2c99e3c BH |
1516 | if (efi.mps != EFI_INVALID_TABLE_ADDR) |
1517 | str += sprintf(str, "MPS=0x%lx\n", efi.mps); | |
1518 | if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) | |
1519 | str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); | |
1520 | if (efi.acpi != EFI_INVALID_TABLE_ADDR) | |
1521 | str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); | |
1522 | if (efi.smbios != EFI_INVALID_TABLE_ADDR) | |
1523 | str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); | |
1524 | if (efi.hcdp != EFI_INVALID_TABLE_ADDR) | |
1525 | str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp); | |
1526 | if (efi.boot_info != EFI_INVALID_TABLE_ADDR) | |
1527 | str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info); | |
1528 | if (efi.uga != EFI_INVALID_TABLE_ADDR) | |
1529 | str += sprintf(str, "UGA=0x%lx\n", efi.uga); | |
1da177e4 LT |
1530 | |
1531 | return str - buf; | |
1532 | } | |
1533 | ||
334c6307 GKH |
1534 | static struct kobj_attribute efi_attr_systab = |
1535 | __ATTR(systab, 0400, systab_show, NULL); | |
1da177e4 | 1536 | |
334c6307 GKH |
1537 | static struct attribute *efi_subsys_attrs[] = { |
1538 | &efi_attr_systab.attr, | |
1da177e4 LT |
1539 | NULL, /* maybe more in the future? */ |
1540 | }; | |
1541 | ||
334c6307 GKH |
1542 | static struct attribute_group efi_subsys_attr_group = { |
1543 | .attrs = efi_subsys_attrs, | |
1544 | }; | |
1545 | ||
bc87d2fe | 1546 | static struct kobject *efi_kobj; |
1da177e4 | 1547 | |
e14ab23d MF |
1548 | /** |
1549 | * efivar_create_sysfs_entry - create a new entry in sysfs | |
1550 | * @new_var: efivar entry to create | |
1551 | * | |
1da177e4 LT |
1552 | * Returns 1 on failure, 0 on success |
1553 | */ | |
1554 | static int | |
e14ab23d | 1555 | efivar_create_sysfs_entry(struct efivar_entry *new_var) |
1da177e4 | 1556 | { |
310ad754 | 1557 | int i, short_name_size; |
1da177e4 | 1558 | char *short_name; |
e14ab23d MF |
1559 | unsigned long variable_name_size; |
1560 | efi_char16_t *variable_name; | |
1561 | ||
1562 | variable_name = new_var->var.VariableName; | |
1563 | variable_name_size = utf16_strlen(variable_name) * sizeof(efi_char16_t); | |
1da177e4 | 1564 | |
310ad754 JK |
1565 | /* |
1566 | * Length of the variable bytes in ASCII, plus the '-' separator, | |
1567 | * plus the GUID, plus trailing NUL | |
1568 | */ | |
1569 | short_name_size = variable_name_size / sizeof(efi_char16_t) | |
e14ab23d | 1570 | + 1 + EFI_VARIABLE_GUID_LEN + 1; |
310ad754 JK |
1571 | |
1572 | short_name = kzalloc(short_name_size, GFP_KERNEL); | |
1da177e4 | 1573 | |
e14ab23d | 1574 | if (!short_name) { |
0933ad9c | 1575 | kfree(short_name); |
1da177e4 LT |
1576 | return 1; |
1577 | } | |
1da177e4 | 1578 | |
1da177e4 LT |
1579 | /* Convert Unicode to normal chars (assume top bits are 0), |
1580 | ala UTF-8 */ | |
1581 | for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) { | |
1582 | short_name[i] = variable_name[i] & 0xFF; | |
1583 | } | |
1584 | /* This is ugly, but necessary to separate one vendor's | |
1585 | private variables from another's. */ | |
1586 | ||
1587 | *(short_name + strlen(short_name)) = '-'; | |
e14ab23d MF |
1588 | efi_guid_unparse(&new_var->var.VendorGuid, |
1589 | short_name + strlen(short_name)); | |
1da177e4 | 1590 | |
e14ab23d | 1591 | new_var->kobj.kset = efivars_kset; |
1da177e4 | 1592 | |
e14ab23d MF |
1593 | i = kobject_init_and_add(&new_var->kobj, &efivar_ktype, |
1594 | NULL, "%s", short_name); | |
0933ad9c | 1595 | kfree(short_name); |
e14ab23d MF |
1596 | if (i) |
1597 | return 1; | |
1da177e4 | 1598 | |
e14ab23d MF |
1599 | kobject_uevent(&new_var->kobj, KOBJ_ADD); |
1600 | efivar_entry_add(new_var, &efivar_sysfs_list); | |
1da177e4 LT |
1601 | |
1602 | return 0; | |
1603 | } | |
d502fbb0 MW |
1604 | |
1605 | static int | |
e14ab23d | 1606 | create_efivars_bin_attributes(void) |
d502fbb0 MW |
1607 | { |
1608 | struct bin_attribute *attr; | |
1609 | int error; | |
1610 | ||
1611 | /* new_var */ | |
1612 | attr = kzalloc(sizeof(*attr), GFP_KERNEL); | |
1613 | if (!attr) | |
1614 | return -ENOMEM; | |
1615 | ||
1616 | attr->attr.name = "new_var"; | |
1617 | attr->attr.mode = 0200; | |
1618 | attr->write = efivar_create; | |
e14ab23d | 1619 | efivars_new_var = attr; |
d502fbb0 MW |
1620 | |
1621 | /* del_var */ | |
1622 | attr = kzalloc(sizeof(*attr), GFP_KERNEL); | |
1623 | if (!attr) { | |
1624 | error = -ENOMEM; | |
1625 | goto out_free; | |
1626 | } | |
1627 | attr->attr.name = "del_var"; | |
1628 | attr->attr.mode = 0200; | |
1629 | attr->write = efivar_delete; | |
e14ab23d | 1630 | efivars_del_var = attr; |
d502fbb0 | 1631 | |
e14ab23d MF |
1632 | sysfs_bin_attr_init(efivars_new_var); |
1633 | sysfs_bin_attr_init(efivars_del_var); | |
d502fbb0 MW |
1634 | |
1635 | /* Register */ | |
e14ab23d | 1636 | error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_new_var); |
d502fbb0 MW |
1637 | if (error) { |
1638 | printk(KERN_ERR "efivars: unable to create new_var sysfs file" | |
1639 | " due to error %d\n", error); | |
1640 | goto out_free; | |
1641 | } | |
e14ab23d MF |
1642 | |
1643 | error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_del_var); | |
d502fbb0 MW |
1644 | if (error) { |
1645 | printk(KERN_ERR "efivars: unable to create del_var sysfs file" | |
1646 | " due to error %d\n", error); | |
e14ab23d | 1647 | sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var); |
d502fbb0 MW |
1648 | goto out_free; |
1649 | } | |
1650 | ||
1651 | return 0; | |
1652 | out_free: | |
e14ab23d MF |
1653 | kfree(efivars_del_var); |
1654 | efivars_del_var = NULL; | |
1655 | kfree(efivars_new_var); | |
1656 | efivars_new_var = NULL; | |
d502fbb0 MW |
1657 | return error; |
1658 | } | |
1659 | ||
e14ab23d MF |
1660 | static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor, |
1661 | unsigned long name_size, void *data) | |
76b53f7c | 1662 | { |
e14ab23d | 1663 | struct efivar_entry *entry; |
4142ef14 | 1664 | |
e14ab23d MF |
1665 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); |
1666 | if (!entry) | |
1667 | return -ENOMEM; | |
4423d779 | 1668 | |
e14ab23d MF |
1669 | memcpy(entry->var.VariableName, name, name_size); |
1670 | memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); | |
1671 | ||
1672 | efivar_create_sysfs_entry(entry); | |
1673 | ||
1674 | return 0; | |
1675 | } | |
1676 | ||
1677 | static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data) | |
1678 | { | |
1679 | efivar_entry_remove(entry); | |
1680 | efivar_unregister(entry); | |
1681 | return 0; | |
76b53f7c | 1682 | } |
1da177e4 | 1683 | |
e971318b MF |
1684 | /* |
1685 | * Print a warning when duplicate EFI variables are encountered and | |
1686 | * disable the sysfs workqueue since the firmware is buggy. | |
1687 | */ | |
1688 | static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid, | |
1689 | unsigned long len16) | |
1690 | { | |
1691 | size_t i, len8 = len16 / sizeof(efi_char16_t); | |
1692 | char *s8; | |
1693 | ||
1694 | /* | |
1695 | * Disable the workqueue since the algorithm it uses for | |
1696 | * detecting new variables won't work with this buggy | |
1697 | * implementation of GetNextVariableName(). | |
1698 | */ | |
1699 | efivar_wq_enabled = false; | |
1700 | ||
1701 | s8 = kzalloc(len8, GFP_KERNEL); | |
1702 | if (!s8) | |
1703 | return; | |
1704 | ||
1705 | for (i = 0; i < len8; i++) | |
1706 | s8[i] = s16[i]; | |
1707 | ||
1708 | printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n", | |
1709 | s8, vendor_guid); | |
1710 | kfree(s8); | |
1711 | } | |
1712 | ||
e14ab23d MF |
1713 | static struct kobject *efivars_kobj; |
1714 | ||
1715 | void efivars_sysfs_exit(void) | |
1da177e4 | 1716 | { |
e14ab23d MF |
1717 | /* Remove all entries and destroy */ |
1718 | __efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL, NULL); | |
1719 | ||
1720 | if (efivars_new_var) | |
1721 | sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var); | |
1722 | if (efivars_del_var) | |
1723 | sysfs_remove_bin_file(&efivars_kset->kobj, efivars_del_var); | |
1724 | kfree(efivars_new_var); | |
1725 | kfree(efivars_del_var); | |
1726 | kobject_put(efivars_kobj); | |
1727 | kset_unregister(efivars_kset); | |
1728 | } | |
1da177e4 | 1729 | |
e14ab23d MF |
1730 | int efivars_sysfs_init(void) |
1731 | { | |
1732 | struct kobject *parent_kobj = efivars_kobject(); | |
1733 | int error = 0; | |
4423d779 | 1734 | |
e14ab23d MF |
1735 | /* No efivars has been registered yet */ |
1736 | if (!parent_kobj) | |
1737 | return 0; | |
1da177e4 | 1738 | |
e14ab23d MF |
1739 | printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, |
1740 | EFIVARS_DATE); | |
29422693 | 1741 | |
e14ab23d MF |
1742 | efivars_kset = kset_create_and_add("vars", NULL, parent_kobj); |
1743 | if (!efivars_kset) { | |
66ac831e | 1744 | printk(KERN_ERR "efivars: Subsystem registration failed.\n"); |
e14ab23d | 1745 | return -ENOMEM; |
1da177e4 LT |
1746 | } |
1747 | ||
e14ab23d MF |
1748 | efivars_kobj = kobject_create_and_add("efivars", parent_kobj); |
1749 | if (!efivars_kobj) { | |
605e70c7 | 1750 | pr_err("efivars: Subsystem registration failed.\n"); |
e14ab23d MF |
1751 | kset_unregister(efivars_kset); |
1752 | return -ENOMEM; | |
1753 | } | |
1754 | ||
1755 | efivar_init(efivars_sysfs_callback, NULL, false, | |
1756 | true, &efivar_sysfs_list); | |
1757 | ||
1758 | error = create_efivars_bin_attributes(); | |
1759 | if (error) | |
1760 | efivars_sysfs_exit(); | |
1761 | ||
1762 | return error; | |
1763 | } | |
1764 | EXPORT_SYMBOL_GPL(efivars_sysfs_init); | |
1765 | ||
1766 | /** | |
1767 | * efivar_init - build the initial list of EFI variables | |
1768 | * @func: callback function to invoke for every variable | |
1769 | * @data: function-specific data to pass to @func | |
1770 | * @atomic: do we need to execute the @func-loop atomically? | |
1771 | * @duplicates: error if we encounter duplicates on @head? | |
1772 | * @head: initialised head of variable list | |
1773 | * | |
1774 | * Get every EFI variable from the firmware and invoke @func. @func | |
1775 | * should call efivar_entry_add() to build the list of variables. | |
1776 | * | |
1777 | * Returns 0 on success, or a kernel error code on failure. | |
1778 | */ | |
1779 | int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *), | |
1780 | void *data, bool atomic, bool duplicates, | |
1781 | struct list_head *head) | |
1782 | { | |
1783 | const struct efivar_operations *ops = __efivars->ops; | |
1784 | unsigned long variable_name_size = 1024; | |
1785 | efi_char16_t *variable_name; | |
1786 | efi_status_t status; | |
1787 | efi_guid_t vendor_guid; | |
1788 | int err = 0; | |
1789 | ||
1790 | variable_name = kzalloc(variable_name_size, GFP_KERNEL); | |
1791 | if (!variable_name) { | |
1792 | printk(KERN_ERR "efivars: Memory allocation failed.\n"); | |
1793 | return -ENOMEM; | |
605e70c7 LCY |
1794 | } |
1795 | ||
e14ab23d MF |
1796 | spin_lock_irq(&__efivars->lock); |
1797 | ||
1da177e4 LT |
1798 | /* |
1799 | * Per EFI spec, the maximum storage allocated for both | |
1800 | * the variable name and variable data is 1024 bytes. | |
1801 | */ | |
1802 | ||
1803 | do { | |
1804 | variable_name_size = 1024; | |
1805 | ||
3295814d | 1806 | status = ops->get_next_variable(&variable_name_size, |
1da177e4 LT |
1807 | variable_name, |
1808 | &vendor_guid); | |
1809 | switch (status) { | |
1810 | case EFI_SUCCESS: | |
e14ab23d MF |
1811 | if (!atomic) |
1812 | spin_unlock_irq(&__efivars->lock); | |
1813 | ||
ec50bd32 MF |
1814 | variable_name_size = var_name_strnsize(variable_name, |
1815 | variable_name_size); | |
e971318b MF |
1816 | |
1817 | /* | |
1818 | * Some firmware implementations return the | |
1819 | * same variable name on multiple calls to | |
1820 | * get_next_variable(). Terminate the loop | |
1821 | * immediately as there is no guarantee that | |
1822 | * we'll ever see a different variable name, | |
1823 | * and may end up looping here forever. | |
1824 | */ | |
e14ab23d MF |
1825 | if (duplicates && |
1826 | variable_is_present(variable_name, &vendor_guid, head)) { | |
e971318b MF |
1827 | dup_variable_bug(variable_name, &vendor_guid, |
1828 | variable_name_size); | |
e14ab23d MF |
1829 | if (!atomic) |
1830 | spin_lock_irq(&__efivars->lock); | |
1831 | ||
e971318b MF |
1832 | status = EFI_NOT_FOUND; |
1833 | break; | |
1834 | } | |
1835 | ||
e14ab23d MF |
1836 | err = func(variable_name, vendor_guid, variable_name_size, data); |
1837 | if (err) | |
1838 | status = EFI_NOT_FOUND; | |
1839 | ||
1840 | if (!atomic) | |
1841 | spin_lock_irq(&__efivars->lock); | |
1842 | ||
1da177e4 LT |
1843 | break; |
1844 | case EFI_NOT_FOUND: | |
1845 | break; | |
1846 | default: | |
1847 | printk(KERN_WARNING "efivars: get_next_variable: status=%lx\n", | |
1848 | status); | |
1849 | status = EFI_NOT_FOUND; | |
1850 | break; | |
1851 | } | |
e14ab23d | 1852 | |
1da177e4 LT |
1853 | } while (status != EFI_NOT_FOUND); |
1854 | ||
e14ab23d MF |
1855 | spin_unlock_irq(&__efivars->lock); |
1856 | ||
1857 | kfree(variable_name); | |
1858 | ||
1859 | return err; | |
1860 | } | |
1861 | EXPORT_SYMBOL_GPL(efivar_init); | |
1862 | ||
1863 | /** | |
1864 | * efivar_entry_add - add entry to variable list | |
1865 | * @entry: entry to add to list | |
1866 | * @head: list head | |
1867 | */ | |
1868 | void efivar_entry_add(struct efivar_entry *entry, struct list_head *head) | |
1869 | { | |
1870 | spin_lock_irq(&__efivars->lock); | |
1871 | list_add(&entry->list, head); | |
1872 | spin_unlock_irq(&__efivars->lock); | |
1873 | } | |
1874 | EXPORT_SYMBOL_GPL(efivar_entry_add); | |
1875 | ||
1876 | /** | |
1877 | * efivar_entry_remove - remove entry from variable list | |
1878 | * @entry: entry to remove from list | |
1879 | */ | |
1880 | void efivar_entry_remove(struct efivar_entry *entry) | |
1881 | { | |
1882 | spin_lock_irq(&__efivars->lock); | |
1883 | list_del(&entry->list); | |
1884 | spin_unlock_irq(&__efivars->lock); | |
1885 | } | |
1886 | EXPORT_SYMBOL_GPL(efivar_entry_remove); | |
1887 | ||
1888 | /* | |
1889 | * efivar_entry_list_del_unlock - remove entry from variable list | |
1890 | * @entry: entry to remove | |
1891 | * | |
1892 | * Remove @entry from the variable list and release the list lock. | |
1893 | * | |
1894 | * NOTE: slightly weird locking semantics here - we expect to be | |
1895 | * called with the efivars lock already held, and we release it before | |
1896 | * returning. This is because this function is usually called after | |
1897 | * set_variable() while the lock is still held. | |
1898 | */ | |
1899 | static void efivar_entry_list_del_unlock(struct efivar_entry *entry) | |
1900 | { | |
1901 | WARN_ON(!spin_is_locked(&__efivars->lock)); | |
1902 | ||
1903 | list_del(&entry->list); | |
1904 | spin_unlock_irq(&__efivars->lock); | |
1905 | } | |
1906 | ||
1907 | /** | |
1908 | * __efivar_entry_delete - delete an EFI variable | |
1909 | * @entry: entry containing EFI variable to delete | |
1910 | * | |
1911 | * Delete the variable from the firmware and remove @entry from the | |
1912 | * variable list. It is the caller's responsibility to free @entry | |
1913 | * once we return. | |
1914 | * | |
1915 | * This function differs from efivar_entry_delete() because it is | |
1916 | * safe to be called from within a efivar_entry_iter_begin() and | |
1917 | * efivar_entry_iter_end() region, unlike efivar_entry_delete(). | |
1918 | * | |
1919 | * Returns 0 on success, or a converted EFI status code if | |
1920 | * set_variable() fails. If set_variable() fails the entry remains | |
1921 | * on the list. | |
1922 | */ | |
1923 | int __efivar_entry_delete(struct efivar_entry *entry) | |
1924 | { | |
1925 | const struct efivar_operations *ops = __efivars->ops; | |
1926 | efi_status_t status; | |
1927 | ||
1928 | WARN_ON(!spin_is_locked(&__efivars->lock)); | |
1929 | ||
1930 | status = ops->set_variable(entry->var.VariableName, | |
1931 | &entry->var.VendorGuid, | |
1932 | 0, 0, NULL); | |
1933 | if (status) | |
1934 | return efi_status_to_err(status); | |
1935 | ||
1936 | list_del(&entry->list); | |
1937 | ||
1938 | return 0; | |
1939 | } | |
1940 | EXPORT_SYMBOL_GPL(__efivar_entry_delete); | |
1941 | ||
1942 | /** | |
1943 | * efivar_entry_delete - delete variable and remove entry from list | |
1944 | * @entry: entry containing variable to delete | |
1945 | * | |
1946 | * Delete the variable from the firmware and remove @entry from the | |
1947 | * variable list. It is the caller's responsibility to free @entry | |
1948 | * once we return. | |
1949 | * | |
1950 | * Returns 0 on success, or a converted EFI status code if | |
1951 | * set_variable() fails. | |
1952 | */ | |
1953 | int efivar_entry_delete(struct efivar_entry *entry) | |
1954 | { | |
1955 | const struct efivar_operations *ops = __efivars->ops; | |
1956 | efi_status_t status; | |
1957 | ||
1958 | spin_lock_irq(&__efivars->lock); | |
1959 | status = ops->set_variable(entry->var.VariableName, | |
1960 | &entry->var.VendorGuid, | |
1961 | 0, 0, NULL); | |
1962 | if (!(status == EFI_SUCCESS || status == EFI_NOT_FOUND)) { | |
1963 | spin_unlock_irq(&__efivars->lock); | |
1964 | return efi_status_to_err(status); | |
1965 | } | |
1966 | ||
1967 | efivar_entry_list_del_unlock(entry); | |
1968 | return 0; | |
1969 | } | |
1970 | EXPORT_SYMBOL_GPL(efivar_entry_delete); | |
1971 | ||
1972 | /** | |
1973 | * efivar_entry_set - call set_variable() | |
1974 | * @entry: entry containing the EFI variable to write | |
1975 | * @attributes: variable attributes | |
1976 | * @size: size of @data buffer | |
1977 | * @data: buffer containing variable data | |
1978 | * @head: head of variable list | |
1979 | * | |
1980 | * Calls set_variable() for an EFI variable. If creating a new EFI | |
1981 | * variable, this function is usually followed by efivar_entry_add(). | |
1982 | * | |
1983 | * Before writing the variable, the remaining EFI variable storage | |
1984 | * space is checked to ensure there is enough room available. | |
1985 | * | |
1986 | * If @head is not NULL a lookup is performed to determine whether | |
1987 | * the entry is already on the list. | |
1988 | * | |
1989 | * Returns 0 on success, -EEXIST if a lookup is performed and the entry | |
1990 | * already exists on the list, or a converted EFI status code if | |
1991 | * set_variable() fails. | |
1992 | */ | |
1993 | int efivar_entry_set(struct efivar_entry *entry, u32 attributes, | |
1994 | unsigned long size, void *data, struct list_head *head) | |
1995 | { | |
1996 | const struct efivar_operations *ops = __efivars->ops; | |
1997 | efi_status_t status; | |
1998 | efi_char16_t *name = entry->var.VariableName; | |
1999 | efi_guid_t vendor = entry->var.VendorGuid; | |
2000 | ||
2001 | spin_lock_irq(&__efivars->lock); | |
2002 | ||
2003 | if (head && efivar_entry_find(name, vendor, head, false)) { | |
2004 | spin_unlock_irq(&__efivars->lock); | |
2005 | return -EEXIST; | |
2006 | } | |
2007 | ||
2008 | status = check_var_size(attributes, size + utf16_strsize(name, 1024)); | |
2009 | if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED) | |
2010 | status = ops->set_variable(name, &vendor, | |
2011 | attributes, size, data); | |
2012 | ||
2013 | spin_unlock_irq(&__efivars->lock); | |
2014 | ||
2015 | return efi_status_to_err(status); | |
2016 | } | |
2017 | EXPORT_SYMBOL_GPL(efivar_entry_set); | |
2018 | ||
2019 | /** | |
2020 | * efivar_entry_set_safe - call set_variable() if enough space in firmware | |
2021 | * @name: buffer containing the variable name | |
2022 | * @vendor: variable vendor guid | |
2023 | * @attributes: variable attributes | |
2024 | * @block: can we block in this context? | |
2025 | * @size: size of @data buffer | |
2026 | * @data: buffer containing variable data | |
2027 | * | |
2028 | * Ensures there is enough free storage in the firmware for this variable, and | |
2029 | * if so, calls set_variable(). If creating a new EFI variable, this function | |
2030 | * is usually followed by efivar_entry_add(). | |
2031 | * | |
2032 | * Returns 0 on success, -ENOSPC if the firmware does not have enough | |
2033 | * space for set_variable() to succeed, or a converted EFI status code | |
2034 | * if set_variable() fails. | |
2035 | */ | |
2036 | int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes, | |
2037 | bool block, unsigned long size, void *data) | |
2038 | { | |
2039 | const struct efivar_operations *ops = __efivars->ops; | |
2040 | unsigned long flags; | |
2041 | efi_status_t status; | |
2042 | ||
2043 | if (!ops->query_variable_info) | |
2044 | return -ENOSYS; | |
2045 | ||
2046 | if (!block && !spin_trylock_irqsave(&__efivars->lock, flags)) | |
2047 | return -EBUSY; | |
2048 | else | |
2049 | spin_lock_irqsave(&__efivars->lock, flags); | |
2050 | ||
2051 | status = check_var_size(attributes, size + utf16_strsize(name, 1024)); | |
2052 | if (status != EFI_SUCCESS) { | |
2053 | spin_unlock_irqrestore(&__efivars->lock, flags); | |
2054 | return -ENOSPC; | |
2055 | } | |
2056 | ||
2057 | status = ops->set_variable(name, &vendor, attributes, size, data); | |
2058 | ||
2059 | spin_unlock_irqrestore(&__efivars->lock, flags); | |
2060 | ||
2061 | return efi_status_to_err(status); | |
2062 | } | |
2063 | EXPORT_SYMBOL_GPL(efivar_entry_set_safe); | |
2064 | ||
2065 | /** | |
2066 | * efivar_entry_find - search for an entry | |
2067 | * @name: the EFI variable name | |
2068 | * @guid: the EFI variable vendor's guid | |
2069 | * @head: head of the variable list | |
2070 | * @remove: should we remove the entry from the list? | |
2071 | * | |
2072 | * Search for an entry on the variable list that has the EFI variable | |
2073 | * name @name and vendor guid @guid. If an entry is found on the list | |
2074 | * and @remove is true, the entry is removed from the list. | |
2075 | * | |
2076 | * The caller MUST call efivar_entry_iter_begin() and | |
2077 | * efivar_entry_iter_end() before and after the invocation of this | |
2078 | * function, respectively. | |
2079 | * | |
2080 | * Returns the entry if found on the list, %NULL otherwise. | |
2081 | */ | |
2082 | struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid, | |
2083 | struct list_head *head, bool remove) | |
2084 | { | |
2085 | struct efivar_entry *entry, *n; | |
2086 | int strsize1, strsize2; | |
2087 | bool found = false; | |
2088 | ||
2089 | WARN_ON(!spin_is_locked(&__efivars->lock)); | |
2090 | ||
2091 | list_for_each_entry_safe(entry, n, head, list) { | |
2092 | strsize1 = utf16_strsize(name, 1024); | |
2093 | strsize2 = utf16_strsize(entry->var.VariableName, 1024); | |
2094 | if (strsize1 == strsize2 && | |
2095 | !memcmp(name, &(entry->var.VariableName), strsize1) && | |
2096 | !efi_guidcmp(guid, entry->var.VendorGuid)) { | |
2097 | found = true; | |
2098 | break; | |
2099 | } | |
2100 | } | |
2101 | ||
2102 | if (!found) | |
2103 | return NULL; | |
2104 | ||
2105 | if (remove) | |
2106 | list_del(&entry->list); | |
2107 | ||
2108 | return entry; | |
2109 | } | |
2110 | EXPORT_SYMBOL_GPL(efivar_entry_find); | |
2111 | ||
2112 | /** | |
2113 | * __efivar_entry_size - obtain the size of a variable | |
2114 | * @entry: entry for this variable | |
2115 | * @size: location to store the variable's size | |
2116 | * | |
2117 | * The caller MUST call efivar_entry_iter_begin() and | |
2118 | * efivar_entry_iter_end() before and after the invocation of this | |
2119 | * function, respectively. | |
2120 | */ | |
2121 | int __efivar_entry_size(struct efivar_entry *entry, unsigned long *size) | |
2122 | { | |
2123 | const struct efivar_operations *ops = __efivars->ops; | |
2124 | efi_status_t status; | |
2125 | ||
2126 | WARN_ON(!spin_is_locked(&__efivars->lock)); | |
2127 | ||
2128 | *size = 0; | |
2129 | status = ops->get_variable(entry->var.VariableName, | |
2130 | &entry->var.VendorGuid, NULL, size, NULL); | |
2131 | if (status != EFI_BUFFER_TOO_SMALL) | |
2132 | return efi_status_to_err(status); | |
2133 | ||
2134 | return 0; | |
2135 | } | |
2136 | EXPORT_SYMBOL_GPL(__efivar_entry_size); | |
2137 | ||
2138 | /** | |
2139 | * efivar_entry_size - obtain the size of a variable | |
2140 | * @entry: entry for this variable | |
2141 | * @size: location to store the variable's size | |
2142 | */ | |
2143 | int efivar_entry_size(struct efivar_entry *entry, unsigned long *size) | |
2144 | { | |
2145 | const struct efivar_operations *ops = __efivars->ops; | |
2146 | efi_status_t status; | |
2147 | ||
2148 | *size = 0; | |
2149 | ||
2150 | spin_lock_irq(&__efivars->lock); | |
2151 | status = ops->get_variable(entry->var.VariableName, | |
2152 | &entry->var.VendorGuid, NULL, size, NULL); | |
2153 | spin_unlock_irq(&__efivars->lock); | |
2154 | ||
2155 | if (status != EFI_BUFFER_TOO_SMALL) | |
2156 | return efi_status_to_err(status); | |
2157 | ||
2158 | return 0; | |
2159 | } | |
2160 | EXPORT_SYMBOL_GPL(efivar_entry_size); | |
2161 | ||
2162 | /** | |
2163 | * efivar_entry_get - call get_variable() | |
2164 | * @entry: read data for this variable | |
2165 | * @attributes: variable attributes | |
2166 | * @size: size of @data buffer | |
2167 | * @data: buffer to store variable data | |
2168 | */ | |
2169 | int efivar_entry_get(struct efivar_entry *entry, u32 *attributes, | |
2170 | unsigned long *size, void *data) | |
2171 | { | |
2172 | const struct efivar_operations *ops = __efivars->ops; | |
2173 | efi_status_t status; | |
2174 | ||
2175 | spin_lock_irq(&__efivars->lock); | |
2176 | status = ops->get_variable(entry->var.VariableName, | |
2177 | &entry->var.VendorGuid, | |
2178 | attributes, size, data); | |
2179 | spin_unlock_irq(&__efivars->lock); | |
2180 | ||
2181 | return efi_status_to_err(status); | |
2182 | } | |
2183 | EXPORT_SYMBOL_GPL(efivar_entry_get); | |
2184 | ||
2185 | /** | |
2186 | * efivar_entry_set_get_size - call set_variable() and get new size (atomic) | |
2187 | * @entry: entry containing variable to set and get | |
2188 | * @attributes: attributes of variable to be written | |
2189 | * @size: size of data buffer | |
2190 | * @data: buffer containing data to write | |
2191 | * @set: did the set_variable() call succeed? | |
2192 | * | |
2193 | * This is a pretty special (complex) function. See efivarfs_file_write(). | |
2194 | * | |
2195 | * Atomically call set_variable() for @entry and if the call is | |
2196 | * successful, return the new size of the variable from get_variable() | |
2197 | * in @size. The success of set_variable() is indicated by @set. | |
2198 | * | |
2199 | * Returns 0 on success, -EINVAL if the variable data is invalid, | |
2200 | * -ENOSPC if the firmware does not have enough available space, or a | |
2201 | * converted EFI status code if either of set_variable() or | |
2202 | * get_variable() fail. | |
2203 | * | |
2204 | * If the EFI variable does not exist when calling set_variable() | |
2205 | * (EFI_NOT_FOUND), @entry is removed from the variable list. | |
2206 | */ | |
2207 | int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes, | |
2208 | unsigned long *size, void *data, bool *set) | |
2209 | { | |
2210 | const struct efivar_operations *ops = __efivars->ops; | |
2211 | efi_char16_t *name = entry->var.VariableName; | |
2212 | efi_guid_t *vendor = &entry->var.VendorGuid; | |
2213 | efi_status_t status; | |
2214 | int err; | |
2215 | ||
2216 | *set = false; | |
2217 | ||
2218 | if (efivar_validate(&entry->var, data, *size) == false) | |
2219 | return -EINVAL; | |
2220 | ||
2221 | /* | |
2222 | * The lock here protects the get_variable call, the conditional | |
2223 | * set_variable call, and removal of the variable from the efivars | |
2224 | * list (in the case of an authenticated delete). | |
2225 | */ | |
2226 | spin_lock_irq(&__efivars->lock); | |
2227 | ||
2228 | /* | |
2229 | * Ensure that the available space hasn't shrunk below the safe level | |
2230 | */ | |
2231 | status = check_var_size(attributes, *size + utf16_strsize(name, 1024)); | |
2232 | if (status != EFI_SUCCESS) { | |
2233 | if (status != EFI_UNSUPPORTED) { | |
2234 | err = efi_status_to_err(status); | |
2235 | goto out; | |
2236 | } | |
2237 | ||
2238 | if (*size > 65536) { | |
2239 | err = -ENOSPC; | |
2240 | goto out; | |
2241 | } | |
2242 | } | |
2243 | ||
2244 | status = ops->set_variable(name, vendor, attributes, *size, data); | |
2245 | if (status != EFI_SUCCESS) { | |
2246 | err = efi_status_to_err(status); | |
2247 | goto out; | |
2248 | } | |
2249 | ||
2250 | *set = true; | |
2251 | ||
2252 | /* | |
2253 | * Writing to the variable may have caused a change in size (which | |
2254 | * could either be an append or an overwrite), or the variable to be | |
2255 | * deleted. Perform a GetVariable() so we can tell what actually | |
2256 | * happened. | |
2257 | */ | |
2258 | *size = 0; | |
2259 | status = ops->get_variable(entry->var.VariableName, | |
2260 | &entry->var.VendorGuid, | |
2261 | NULL, size, NULL); | |
2262 | ||
2263 | if (status == EFI_NOT_FOUND) | |
2264 | efivar_entry_list_del_unlock(entry); | |
2265 | else | |
2266 | spin_unlock_irq(&__efivars->lock); | |
2267 | ||
2268 | if (status && status != EFI_BUFFER_TOO_SMALL) | |
2269 | return efi_status_to_err(status); | |
2270 | ||
2271 | return 0; | |
2272 | ||
2273 | out: | |
2274 | spin_unlock_irq(&__efivars->lock); | |
2275 | return err; | |
2276 | ||
2277 | } | |
2278 | EXPORT_SYMBOL_GPL(efivar_entry_set_get_size); | |
2279 | ||
2280 | /** | |
2281 | * efivar_entry_iter_begin - begin iterating the variable list | |
2282 | * | |
2283 | * Lock the variable list to prevent entry insertion and removal until | |
2284 | * efivar_entry_iter_end() is called. This function is usually used in | |
2285 | * conjunction with __efivar_entry_iter() or efivar_entry_iter(). | |
2286 | */ | |
2287 | void efivar_entry_iter_begin(void) | |
2288 | { | |
2289 | spin_lock_irq(&__efivars->lock); | |
2290 | } | |
2291 | EXPORT_SYMBOL_GPL(efivar_entry_iter_begin); | |
2292 | ||
2293 | /** | |
2294 | * efivar_entry_iter_end - finish iterating the variable list | |
2295 | * | |
2296 | * Unlock the variable list and allow modifications to the list again. | |
2297 | */ | |
2298 | void efivar_entry_iter_end(void) | |
2299 | { | |
2300 | spin_unlock_irq(&__efivars->lock); | |
2301 | } | |
2302 | EXPORT_SYMBOL_GPL(efivar_entry_iter_end); | |
2303 | ||
2304 | /** | |
2305 | * __efivar_entry_iter - iterate over variable list | |
2306 | * @func: callback function | |
2307 | * @head: head of the variable list | |
2308 | * @data: function-specific data to pass to callback | |
2309 | * @prev: entry to begin iterating from | |
2310 | * | |
2311 | * Iterate over the list of EFI variables and call @func with every | |
2312 | * entry on the list. It is safe for @func to remove entries in the | |
2313 | * list via efivar_entry_delete(). | |
2314 | * | |
2315 | * You MUST call efivar_enter_iter_begin() before this function, and | |
2316 | * efivar_entry_iter_end() afterwards. | |
2317 | * | |
2318 | * It is possible to begin iteration from an arbitrary entry within | |
2319 | * the list by passing @prev. @prev is updated on return to point to | |
2320 | * the last entry passed to @func. To begin iterating from the | |
2321 | * beginning of the list @prev must be %NULL. | |
2322 | * | |
2323 | * The restrictions for @func are the same as documented for | |
2324 | * efivar_entry_iter(). | |
2325 | */ | |
2326 | int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *), | |
2327 | struct list_head *head, void *data, | |
2328 | struct efivar_entry **prev) | |
2329 | { | |
2330 | struct efivar_entry *entry, *n; | |
2331 | int err = 0; | |
2332 | ||
2333 | if (!prev || !*prev) { | |
2334 | list_for_each_entry_safe(entry, n, head, list) { | |
2335 | err = func(entry, data); | |
2336 | if (err) | |
2337 | break; | |
2338 | } | |
2339 | ||
2340 | if (prev) | |
2341 | *prev = entry; | |
2342 | ||
2343 | return err; | |
2344 | } | |
2345 | ||
2346 | ||
2347 | list_for_each_entry_safe_continue((*prev), n, head, list) { | |
2348 | err = func(*prev, data); | |
2349 | if (err) | |
2350 | break; | |
2351 | } | |
2352 | ||
2353 | return err; | |
2354 | } | |
2355 | EXPORT_SYMBOL_GPL(__efivar_entry_iter); | |
2356 | ||
2357 | /** | |
2358 | * efivar_entry_iter - iterate over variable list | |
2359 | * @func: callback function | |
2360 | * @head: head of variable list | |
2361 | * @data: function-specific data to pass to callback | |
2362 | * | |
2363 | * Iterate over the list of EFI variables and call @func with every | |
2364 | * entry on the list. It is safe for @func to remove entries in the | |
2365 | * list via efivar_entry_delete() while iterating. | |
2366 | * | |
2367 | * Some notes for the callback function: | |
2368 | * - a non-zero return value indicates an error and terminates the loop | |
2369 | * - @func is called from atomic context | |
2370 | */ | |
2371 | int efivar_entry_iter(int (*func)(struct efivar_entry *, void *), | |
2372 | struct list_head *head, void *data) | |
2373 | { | |
2374 | int err = 0; | |
2375 | ||
2376 | efivar_entry_iter_begin(); | |
2377 | err = __efivar_entry_iter(func, head, data, NULL); | |
2378 | efivar_entry_iter_end(); | |
2379 | ||
2380 | return err; | |
2381 | } | |
2382 | EXPORT_SYMBOL_GPL(efivar_entry_iter); | |
2383 | ||
2384 | /** | |
2385 | * efivars_kobject - get the kobject for the registered efivars | |
2386 | * | |
2387 | * If efivars_register() has not been called we return NULL, | |
2388 | * otherwise return the kobject used at registration time. | |
2389 | */ | |
2390 | struct kobject *efivars_kobject(void) | |
2391 | { | |
2392 | if (!__efivars) | |
2393 | return NULL; | |
2394 | ||
2395 | return __efivars->kobject; | |
2396 | } | |
2397 | EXPORT_SYMBOL_GPL(efivars_kobject); | |
2398 | ||
2399 | /** | |
2400 | * efivars_register - register an efivars | |
2401 | * @efivars: efivars to register | |
2402 | * @ops: efivars operations | |
2403 | * @kobject: @efivars-specific kobject | |
2404 | * | |
2405 | * Only a single efivars can be registered at any time. | |
2406 | */ | |
2407 | int efivars_register(struct efivars *efivars, | |
2408 | const struct efivar_operations *ops, | |
2409 | struct kobject *kobject) | |
2410 | { | |
2411 | spin_lock_init(&efivars->lock); | |
2412 | efivars->ops = ops; | |
2413 | efivars->kobject = kobject; | |
2414 | ||
2415 | __efivars = efivars; | |
1da177e4 | 2416 | |
ec0971ba | 2417 | if (!efivars_pstore_disable) |
e14ab23d | 2418 | efivar_pstore_register(); |
5ee9c198 | 2419 | |
5d9db883 MG |
2420 | register_filesystem(&efivarfs_type); |
2421 | ||
e14ab23d MF |
2422 | return 0; |
2423 | } | |
2424 | EXPORT_SYMBOL_GPL(efivars_register); | |
1da177e4 | 2425 | |
e14ab23d MF |
2426 | /** |
2427 | * efivars_unregister - unregister an efivars | |
2428 | * @efivars: efivars to unregister | |
2429 | * | |
2430 | * The caller must have already removed every entry from the list, | |
2431 | * failure to do so is an error. | |
2432 | */ | |
2433 | int efivars_unregister(struct efivars *efivars) | |
2434 | { | |
2435 | int rv; | |
2436 | ||
2437 | if (!__efivars) { | |
2438 | printk(KERN_ERR "efivars not registered\n"); | |
2439 | rv = -EINVAL; | |
2440 | goto out; | |
2441 | } | |
2442 | ||
2443 | if (__efivars != efivars) { | |
2444 | rv = -EINVAL; | |
2445 | goto out; | |
2446 | } | |
2447 | ||
2448 | __efivars = NULL; | |
2449 | ||
2450 | rv = 0; | |
2451 | out: | |
2452 | return rv; | |
76b53f7c | 2453 | } |
e14ab23d | 2454 | EXPORT_SYMBOL_GPL(efivars_unregister); |
1da177e4 | 2455 | |
4423d779 MF |
2456 | static struct efivars generic_efivars; |
2457 | static struct efivar_operations generic_ops; | |
2458 | ||
2459 | static int generic_ops_register(void) | |
2460 | { | |
e14ab23d MF |
2461 | int error; |
2462 | ||
4423d779 MF |
2463 | generic_ops.get_variable = efi.get_variable; |
2464 | generic_ops.set_variable = efi.set_variable; | |
2465 | generic_ops.get_next_variable = efi.get_next_variable; | |
2466 | generic_ops.query_variable_info = efi.query_variable_info; | |
2467 | ||
e14ab23d MF |
2468 | error = efivars_register(&generic_efivars, &generic_ops, efi_kobj); |
2469 | if (error) | |
2470 | return error; | |
2471 | ||
2472 | error = efivars_sysfs_init(); | |
2473 | if (error) | |
2474 | efivars_unregister(&generic_efivars); | |
2475 | ||
2476 | return error; | |
4423d779 MF |
2477 | } |
2478 | ||
2479 | static void generic_ops_unregister(void) | |
2480 | { | |
e14ab23d MF |
2481 | efivars_sysfs_exit(); |
2482 | efivars_unregister(&generic_efivars); | |
4423d779 MF |
2483 | } |
2484 | ||
76b53f7c MW |
2485 | /* |
2486 | * For now we register the efi subsystem with the firmware subsystem | |
2487 | * and the vars subsystem with the efi subsystem. In the future, it | |
2488 | * might make sense to split off the efi subsystem into its own | |
2489 | * driver, but for now only efivars will register with it, so just | |
2490 | * include it here. | |
2491 | */ | |
2492 | ||
2493 | static int __init | |
2494 | efivars_init(void) | |
2495 | { | |
e14ab23d | 2496 | int error; |
76b53f7c | 2497 | |
83e68189 | 2498 | if (!efi_enabled(EFI_RUNTIME_SERVICES)) |
4fc756bd | 2499 | return 0; |
76b53f7c | 2500 | |
e14ab23d | 2501 | /* Register the efi directory at /sys/firmware/efi */ |
76b53f7c MW |
2502 | efi_kobj = kobject_create_and_add("efi", firmware_kobj); |
2503 | if (!efi_kobj) { | |
2504 | printk(KERN_ERR "efivars: Firmware registration failed.\n"); | |
2505 | return -ENOMEM; | |
2506 | } | |
2507 | ||
4423d779 | 2508 | error = generic_ops_register(); |
3116aabc DC |
2509 | if (error) |
2510 | goto err_put; | |
76b53f7c MW |
2511 | |
2512 | /* Don't forget the systab entry */ | |
2513 | error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); | |
2514 | if (error) { | |
2515 | printk(KERN_ERR | |
2516 | "efivars: Sysfs attribute export failed with error %d.\n", | |
2517 | error); | |
3116aabc | 2518 | goto err_unregister; |
76b53f7c | 2519 | } |
1da177e4 | 2520 | |
3116aabc DC |
2521 | return 0; |
2522 | ||
2523 | err_unregister: | |
4423d779 | 2524 | generic_ops_unregister(); |
3116aabc DC |
2525 | err_put: |
2526 | kobject_put(efi_kobj); | |
1da177e4 LT |
2527 | return error; |
2528 | } | |
2529 | ||
2530 | static void __exit | |
2531 | efivars_exit(void) | |
2532 | { | |
a93bc0c6 SA |
2533 | cancel_work_sync(&efivar_work); |
2534 | ||
83e68189 | 2535 | if (efi_enabled(EFI_RUNTIME_SERVICES)) { |
4423d779 | 2536 | generic_ops_unregister(); |
aabb6e15 RD |
2537 | kobject_put(efi_kobj); |
2538 | } | |
1da177e4 LT |
2539 | } |
2540 | ||
2541 | module_init(efivars_init); | |
2542 | module_exit(efivars_exit); | |
2543 |