Commit | Line | Data |
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09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
948af1f0 MW |
2 | /* |
3 | * dmi-sysfs.c | |
4 | * | |
5 | * This module exports the DMI tables read-only to userspace through the | |
6 | * sysfs file system. | |
7 | * | |
8 | * Data is currently found below | |
9 | * /sys/firmware/dmi/... | |
10 | * | |
11 | * DMI attributes are presented in attribute files with names | |
12 | * formatted using %d-%d, so that the first integer indicates the | |
13 | * structure type (0-255), and the second field is the instance of that | |
14 | * entry. | |
15 | * | |
16 | * Copyright 2011 Google, Inc. | |
17 | */ | |
18 | ||
19 | #include <linux/kernel.h> | |
20 | #include <linux/init.h> | |
21 | #include <linux/module.h> | |
22 | #include <linux/types.h> | |
23 | #include <linux/kobject.h> | |
24 | #include <linux/dmi.h> | |
25 | #include <linux/capability.h> | |
26 | #include <linux/slab.h> | |
27 | #include <linux/list.h> | |
28 | #include <linux/io.h> | |
f7750a79 | 29 | #include <asm/dmi.h> |
948af1f0 MW |
30 | |
31 | #define MAX_ENTRY_TYPE 255 /* Most of these aren't used, but we consider | |
32 | the top entry type is only 8 bits */ | |
33 | ||
34 | struct dmi_sysfs_entry { | |
35 | struct dmi_header dh; | |
36 | struct kobject kobj; | |
37 | int instance; | |
38 | int position; | |
39 | struct list_head list; | |
925a1da7 | 40 | struct kobject *child; |
948af1f0 MW |
41 | }; |
42 | ||
43 | /* | |
44 | * Global list of dmi_sysfs_entry. Even though this should only be | |
45 | * manipulated at setup and teardown, the lazy nature of the kobject | |
46 | * system means we get lazy removes. | |
47 | */ | |
48 | static LIST_HEAD(entry_list); | |
49 | static DEFINE_SPINLOCK(entry_list_lock); | |
50 | ||
51 | /* dmi_sysfs_attribute - Top level attribute. used by all entries. */ | |
52 | struct dmi_sysfs_attribute { | |
53 | struct attribute attr; | |
54 | ssize_t (*show)(struct dmi_sysfs_entry *entry, char *buf); | |
55 | }; | |
56 | ||
57 | #define DMI_SYSFS_ATTR(_entry, _name) \ | |
58 | struct dmi_sysfs_attribute dmi_sysfs_attr_##_entry##_##_name = { \ | |
59 | .attr = {.name = __stringify(_name), .mode = 0400}, \ | |
60 | .show = dmi_sysfs_##_entry##_##_name, \ | |
61 | } | |
62 | ||
63 | /* | |
64 | * dmi_sysfs_mapped_attribute - Attribute where we require the entry be | |
65 | * mapped in. Use in conjunction with dmi_sysfs_specialize_attr_ops. | |
66 | */ | |
67 | struct dmi_sysfs_mapped_attribute { | |
68 | struct attribute attr; | |
69 | ssize_t (*show)(struct dmi_sysfs_entry *entry, | |
70 | const struct dmi_header *dh, | |
71 | char *buf); | |
72 | }; | |
73 | ||
74 | #define DMI_SYSFS_MAPPED_ATTR(_entry, _name) \ | |
75 | struct dmi_sysfs_mapped_attribute dmi_sysfs_attr_##_entry##_##_name = { \ | |
76 | .attr = {.name = __stringify(_name), .mode = 0400}, \ | |
77 | .show = dmi_sysfs_##_entry##_##_name, \ | |
78 | } | |
79 | ||
80 | /************************************************* | |
81 | * Generic DMI entry support. | |
82 | *************************************************/ | |
925a1da7 MW |
83 | static void dmi_entry_free(struct kobject *kobj) |
84 | { | |
85 | kfree(kobj); | |
86 | } | |
948af1f0 MW |
87 | |
88 | static struct dmi_sysfs_entry *to_entry(struct kobject *kobj) | |
89 | { | |
90 | return container_of(kobj, struct dmi_sysfs_entry, kobj); | |
91 | } | |
92 | ||
93 | static struct dmi_sysfs_attribute *to_attr(struct attribute *attr) | |
94 | { | |
95 | return container_of(attr, struct dmi_sysfs_attribute, attr); | |
96 | } | |
97 | ||
98 | static ssize_t dmi_sysfs_attr_show(struct kobject *kobj, | |
99 | struct attribute *_attr, char *buf) | |
100 | { | |
101 | struct dmi_sysfs_entry *entry = to_entry(kobj); | |
102 | struct dmi_sysfs_attribute *attr = to_attr(_attr); | |
103 | ||
104 | /* DMI stuff is only ever admin visible */ | |
105 | if (!capable(CAP_SYS_ADMIN)) | |
106 | return -EACCES; | |
107 | ||
108 | return attr->show(entry, buf); | |
109 | } | |
110 | ||
111 | static const struct sysfs_ops dmi_sysfs_attr_ops = { | |
112 | .show = dmi_sysfs_attr_show, | |
113 | }; | |
114 | ||
115 | typedef ssize_t (*dmi_callback)(struct dmi_sysfs_entry *, | |
116 | const struct dmi_header *dh, void *); | |
117 | ||
118 | struct find_dmi_data { | |
119 | struct dmi_sysfs_entry *entry; | |
120 | dmi_callback callback; | |
121 | void *private; | |
122 | int instance_countdown; | |
123 | ssize_t ret; | |
124 | }; | |
125 | ||
126 | static void find_dmi_entry_helper(const struct dmi_header *dh, | |
127 | void *_data) | |
128 | { | |
129 | struct find_dmi_data *data = _data; | |
130 | struct dmi_sysfs_entry *entry = data->entry; | |
131 | ||
132 | /* Is this the entry we want? */ | |
133 | if (dh->type != entry->dh.type) | |
134 | return; | |
135 | ||
136 | if (data->instance_countdown != 0) { | |
137 | /* try the next instance? */ | |
138 | data->instance_countdown--; | |
139 | return; | |
140 | } | |
141 | ||
142 | /* | |
143 | * Don't ever revisit the instance. Short circuit later | |
144 | * instances by letting the instance_countdown run negative | |
145 | */ | |
146 | data->instance_countdown--; | |
147 | ||
148 | /* Found the entry */ | |
149 | data->ret = data->callback(entry, dh, data->private); | |
150 | } | |
151 | ||
152 | /* State for passing the read parameters through dmi_find_entry() */ | |
153 | struct dmi_read_state { | |
154 | char *buf; | |
155 | loff_t pos; | |
156 | size_t count; | |
157 | }; | |
158 | ||
159 | static ssize_t find_dmi_entry(struct dmi_sysfs_entry *entry, | |
160 | dmi_callback callback, void *private) | |
161 | { | |
162 | struct find_dmi_data data = { | |
163 | .entry = entry, | |
164 | .callback = callback, | |
165 | .private = private, | |
166 | .instance_countdown = entry->instance, | |
167 | .ret = -EIO, /* To signal the entry disappeared */ | |
168 | }; | |
169 | int ret; | |
170 | ||
171 | ret = dmi_walk(find_dmi_entry_helper, &data); | |
172 | /* This shouldn't happen, but just in case. */ | |
173 | if (ret) | |
174 | return -EINVAL; | |
175 | return data.ret; | |
176 | } | |
177 | ||
178 | /* | |
179 | * Calculate and return the byte length of the dmi entry identified by | |
180 | * dh. This includes both the formatted portion as well as the | |
181 | * unformatted string space, including the two trailing nul characters. | |
182 | */ | |
183 | static size_t dmi_entry_length(const struct dmi_header *dh) | |
184 | { | |
185 | const char *p = (const char *)dh; | |
186 | ||
187 | p += dh->length; | |
188 | ||
189 | while (p[0] || p[1]) | |
190 | p++; | |
191 | ||
192 | return 2 + p - (const char *)dh; | |
193 | } | |
194 | ||
925a1da7 MW |
195 | /************************************************* |
196 | * Support bits for specialized DMI entry support | |
197 | *************************************************/ | |
198 | struct dmi_entry_attr_show_data { | |
199 | struct attribute *attr; | |
200 | char *buf; | |
201 | }; | |
202 | ||
203 | static ssize_t dmi_entry_attr_show_helper(struct dmi_sysfs_entry *entry, | |
204 | const struct dmi_header *dh, | |
205 | void *_data) | |
206 | { | |
207 | struct dmi_entry_attr_show_data *data = _data; | |
208 | struct dmi_sysfs_mapped_attribute *attr; | |
209 | ||
210 | attr = container_of(data->attr, | |
211 | struct dmi_sysfs_mapped_attribute, attr); | |
212 | return attr->show(entry, dh, data->buf); | |
213 | } | |
214 | ||
215 | static ssize_t dmi_entry_attr_show(struct kobject *kobj, | |
216 | struct attribute *attr, | |
217 | char *buf) | |
218 | { | |
219 | struct dmi_entry_attr_show_data data = { | |
220 | .attr = attr, | |
221 | .buf = buf, | |
222 | }; | |
223 | /* Find the entry according to our parent and call the | |
224 | * normalized show method hanging off of the attribute */ | |
225 | return find_dmi_entry(to_entry(kobj->parent), | |
226 | dmi_entry_attr_show_helper, &data); | |
227 | } | |
228 | ||
229 | static const struct sysfs_ops dmi_sysfs_specialize_attr_ops = { | |
230 | .show = dmi_entry_attr_show, | |
231 | }; | |
232 | ||
233 | /************************************************* | |
234 | * Specialized DMI entry support. | |
235 | *************************************************/ | |
236 | ||
237 | /*** Type 15 - System Event Table ***/ | |
238 | ||
239 | #define DMI_SEL_ACCESS_METHOD_IO8 0x00 | |
240 | #define DMI_SEL_ACCESS_METHOD_IO2x8 0x01 | |
241 | #define DMI_SEL_ACCESS_METHOD_IO16 0x02 | |
242 | #define DMI_SEL_ACCESS_METHOD_PHYS32 0x03 | |
243 | #define DMI_SEL_ACCESS_METHOD_GPNV 0x04 | |
244 | ||
245 | struct dmi_system_event_log { | |
246 | struct dmi_header header; | |
247 | u16 area_length; | |
248 | u16 header_start_offset; | |
249 | u16 data_start_offset; | |
250 | u8 access_method; | |
251 | u8 status; | |
252 | u32 change_token; | |
253 | union { | |
254 | struct { | |
255 | u16 index_addr; | |
256 | u16 data_addr; | |
257 | } io; | |
258 | u32 phys_addr32; | |
259 | u16 gpnv_handle; | |
260 | u32 access_method_address; | |
261 | }; | |
262 | u8 header_format; | |
263 | u8 type_descriptors_supported_count; | |
264 | u8 per_log_type_descriptor_length; | |
8e849a41 | 265 | u8 supported_log_type_descriptos[]; |
925a1da7 MW |
266 | } __packed; |
267 | ||
925a1da7 MW |
268 | #define DMI_SYSFS_SEL_FIELD(_field) \ |
269 | static ssize_t dmi_sysfs_sel_##_field(struct dmi_sysfs_entry *entry, \ | |
270 | const struct dmi_header *dh, \ | |
271 | char *buf) \ | |
272 | { \ | |
66245ad0 MW |
273 | struct dmi_system_event_log sel; \ |
274 | if (sizeof(sel) > dmi_entry_length(dh)) \ | |
925a1da7 | 275 | return -EIO; \ |
66245ad0 MW |
276 | memcpy(&sel, dh, sizeof(sel)); \ |
277 | return sprintf(buf, "%u\n", sel._field); \ | |
925a1da7 MW |
278 | } \ |
279 | static DMI_SYSFS_MAPPED_ATTR(sel, _field) | |
280 | ||
281 | DMI_SYSFS_SEL_FIELD(area_length); | |
282 | DMI_SYSFS_SEL_FIELD(header_start_offset); | |
283 | DMI_SYSFS_SEL_FIELD(data_start_offset); | |
284 | DMI_SYSFS_SEL_FIELD(access_method); | |
285 | DMI_SYSFS_SEL_FIELD(status); | |
286 | DMI_SYSFS_SEL_FIELD(change_token); | |
287 | DMI_SYSFS_SEL_FIELD(access_method_address); | |
288 | DMI_SYSFS_SEL_FIELD(header_format); | |
289 | DMI_SYSFS_SEL_FIELD(type_descriptors_supported_count); | |
290 | DMI_SYSFS_SEL_FIELD(per_log_type_descriptor_length); | |
291 | ||
292 | static struct attribute *dmi_sysfs_sel_attrs[] = { | |
293 | &dmi_sysfs_attr_sel_area_length.attr, | |
294 | &dmi_sysfs_attr_sel_header_start_offset.attr, | |
295 | &dmi_sysfs_attr_sel_data_start_offset.attr, | |
296 | &dmi_sysfs_attr_sel_access_method.attr, | |
297 | &dmi_sysfs_attr_sel_status.attr, | |
298 | &dmi_sysfs_attr_sel_change_token.attr, | |
299 | &dmi_sysfs_attr_sel_access_method_address.attr, | |
300 | &dmi_sysfs_attr_sel_header_format.attr, | |
301 | &dmi_sysfs_attr_sel_type_descriptors_supported_count.attr, | |
302 | &dmi_sysfs_attr_sel_per_log_type_descriptor_length.attr, | |
303 | NULL, | |
304 | }; | |
ab6d0f57 | 305 | ATTRIBUTE_GROUPS(dmi_sysfs_sel); |
925a1da7 | 306 | |
81773c98 | 307 | static const struct kobj_type dmi_system_event_log_ktype = { |
925a1da7 MW |
308 | .release = dmi_entry_free, |
309 | .sysfs_ops = &dmi_sysfs_specialize_attr_ops, | |
ab6d0f57 | 310 | .default_groups = dmi_sysfs_sel_groups, |
925a1da7 MW |
311 | }; |
312 | ||
e7f3dd80 | 313 | #ifdef CONFIG_HAS_IOPORT |
a3857a5c MW |
314 | typedef u8 (*sel_io_reader)(const struct dmi_system_event_log *sel, |
315 | loff_t offset); | |
316 | ||
317 | static DEFINE_MUTEX(io_port_lock); | |
318 | ||
319 | static u8 read_sel_8bit_indexed_io(const struct dmi_system_event_log *sel, | |
320 | loff_t offset) | |
321 | { | |
322 | u8 ret; | |
323 | ||
324 | mutex_lock(&io_port_lock); | |
325 | outb((u8)offset, sel->io.index_addr); | |
326 | ret = inb(sel->io.data_addr); | |
327 | mutex_unlock(&io_port_lock); | |
328 | return ret; | |
329 | } | |
330 | ||
331 | static u8 read_sel_2x8bit_indexed_io(const struct dmi_system_event_log *sel, | |
332 | loff_t offset) | |
333 | { | |
334 | u8 ret; | |
335 | ||
336 | mutex_lock(&io_port_lock); | |
337 | outb((u8)offset, sel->io.index_addr); | |
338 | outb((u8)(offset >> 8), sel->io.index_addr + 1); | |
339 | ret = inb(sel->io.data_addr); | |
340 | mutex_unlock(&io_port_lock); | |
341 | return ret; | |
342 | } | |
343 | ||
344 | static u8 read_sel_16bit_indexed_io(const struct dmi_system_event_log *sel, | |
345 | loff_t offset) | |
346 | { | |
347 | u8 ret; | |
348 | ||
349 | mutex_lock(&io_port_lock); | |
350 | outw((u16)offset, sel->io.index_addr); | |
351 | ret = inb(sel->io.data_addr); | |
352 | mutex_unlock(&io_port_lock); | |
353 | return ret; | |
354 | } | |
355 | ||
356 | static sel_io_reader sel_io_readers[] = { | |
357 | [DMI_SEL_ACCESS_METHOD_IO8] = read_sel_8bit_indexed_io, | |
358 | [DMI_SEL_ACCESS_METHOD_IO2x8] = read_sel_2x8bit_indexed_io, | |
359 | [DMI_SEL_ACCESS_METHOD_IO16] = read_sel_16bit_indexed_io, | |
360 | }; | |
361 | ||
362 | static ssize_t dmi_sel_raw_read_io(struct dmi_sysfs_entry *entry, | |
363 | const struct dmi_system_event_log *sel, | |
364 | char *buf, loff_t pos, size_t count) | |
365 | { | |
366 | ssize_t wrote = 0; | |
367 | ||
368 | sel_io_reader io_reader = sel_io_readers[sel->access_method]; | |
369 | ||
370 | while (count && pos < sel->area_length) { | |
371 | count--; | |
372 | *(buf++) = io_reader(sel, pos++); | |
373 | wrote++; | |
374 | } | |
375 | ||
376 | return wrote; | |
377 | } | |
e7f3dd80 | 378 | #endif |
a3857a5c MW |
379 | |
380 | static ssize_t dmi_sel_raw_read_phys32(struct dmi_sysfs_entry *entry, | |
381 | const struct dmi_system_event_log *sel, | |
382 | char *buf, loff_t pos, size_t count) | |
383 | { | |
384 | u8 __iomem *mapped; | |
385 | ssize_t wrote = 0; | |
386 | ||
f7750a79 | 387 | mapped = dmi_remap(sel->access_method_address, sel->area_length); |
a3857a5c MW |
388 | if (!mapped) |
389 | return -EIO; | |
390 | ||
391 | while (count && pos < sel->area_length) { | |
392 | count--; | |
393 | *(buf++) = readb(mapped + pos++); | |
394 | wrote++; | |
395 | } | |
396 | ||
f7750a79 | 397 | dmi_unmap(mapped); |
a3857a5c MW |
398 | return wrote; |
399 | } | |
400 | ||
401 | static ssize_t dmi_sel_raw_read_helper(struct dmi_sysfs_entry *entry, | |
402 | const struct dmi_header *dh, | |
403 | void *_state) | |
404 | { | |
405 | struct dmi_read_state *state = _state; | |
66245ad0 | 406 | struct dmi_system_event_log sel; |
a3857a5c | 407 | |
66245ad0 | 408 | if (sizeof(sel) > dmi_entry_length(dh)) |
a3857a5c MW |
409 | return -EIO; |
410 | ||
66245ad0 MW |
411 | memcpy(&sel, dh, sizeof(sel)); |
412 | ||
413 | switch (sel.access_method) { | |
e7f3dd80 | 414 | #ifdef CONFIG_HAS_IOPORT |
a3857a5c MW |
415 | case DMI_SEL_ACCESS_METHOD_IO8: |
416 | case DMI_SEL_ACCESS_METHOD_IO2x8: | |
417 | case DMI_SEL_ACCESS_METHOD_IO16: | |
66245ad0 | 418 | return dmi_sel_raw_read_io(entry, &sel, state->buf, |
a3857a5c | 419 | state->pos, state->count); |
e7f3dd80 | 420 | #endif |
a3857a5c | 421 | case DMI_SEL_ACCESS_METHOD_PHYS32: |
66245ad0 | 422 | return dmi_sel_raw_read_phys32(entry, &sel, state->buf, |
a3857a5c MW |
423 | state->pos, state->count); |
424 | case DMI_SEL_ACCESS_METHOD_GPNV: | |
7d12970f | 425 | pr_info_ratelimited("dmi-sysfs: GPNV support missing.\n"); |
a3857a5c MW |
426 | return -EIO; |
427 | default: | |
7d12970f | 428 | pr_info_ratelimited("dmi-sysfs: Unknown access method %02x\n", |
66245ad0 | 429 | sel.access_method); |
a3857a5c MW |
430 | return -EIO; |
431 | } | |
432 | } | |
433 | ||
434 | static ssize_t dmi_sel_raw_read(struct file *filp, struct kobject *kobj, | |
435 | struct bin_attribute *bin_attr, | |
436 | char *buf, loff_t pos, size_t count) | |
437 | { | |
438 | struct dmi_sysfs_entry *entry = to_entry(kobj->parent); | |
439 | struct dmi_read_state state = { | |
440 | .buf = buf, | |
441 | .pos = pos, | |
442 | .count = count, | |
443 | }; | |
444 | ||
445 | return find_dmi_entry(entry, dmi_sel_raw_read_helper, &state); | |
446 | } | |
447 | ||
448 | static struct bin_attribute dmi_sel_raw_attr = { | |
449 | .attr = {.name = "raw_event_log", .mode = 0400}, | |
450 | .read = dmi_sel_raw_read, | |
451 | }; | |
452 | ||
925a1da7 MW |
453 | static int dmi_system_event_log(struct dmi_sysfs_entry *entry) |
454 | { | |
455 | int ret; | |
456 | ||
457 | entry->child = kzalloc(sizeof(*entry->child), GFP_KERNEL); | |
458 | if (!entry->child) | |
459 | return -ENOMEM; | |
460 | ret = kobject_init_and_add(entry->child, | |
461 | &dmi_system_event_log_ktype, | |
462 | &entry->kobj, | |
463 | "system_event_log"); | |
464 | if (ret) | |
465 | goto out_free; | |
a3857a5c MW |
466 | |
467 | ret = sysfs_create_bin_file(entry->child, &dmi_sel_raw_attr); | |
468 | if (ret) | |
469 | goto out_del; | |
470 | ||
471 | return 0; | |
472 | ||
473 | out_del: | |
474 | kobject_del(entry->child); | |
925a1da7 MW |
475 | out_free: |
476 | kfree(entry->child); | |
477 | return ret; | |
478 | } | |
479 | ||
948af1f0 MW |
480 | /************************************************* |
481 | * Generic DMI entry support. | |
482 | *************************************************/ | |
483 | ||
484 | static ssize_t dmi_sysfs_entry_length(struct dmi_sysfs_entry *entry, char *buf) | |
485 | { | |
486 | return sprintf(buf, "%d\n", entry->dh.length); | |
487 | } | |
488 | ||
489 | static ssize_t dmi_sysfs_entry_handle(struct dmi_sysfs_entry *entry, char *buf) | |
490 | { | |
491 | return sprintf(buf, "%d\n", entry->dh.handle); | |
492 | } | |
493 | ||
494 | static ssize_t dmi_sysfs_entry_type(struct dmi_sysfs_entry *entry, char *buf) | |
495 | { | |
496 | return sprintf(buf, "%d\n", entry->dh.type); | |
497 | } | |
498 | ||
499 | static ssize_t dmi_sysfs_entry_instance(struct dmi_sysfs_entry *entry, | |
500 | char *buf) | |
501 | { | |
502 | return sprintf(buf, "%d\n", entry->instance); | |
503 | } | |
504 | ||
505 | static ssize_t dmi_sysfs_entry_position(struct dmi_sysfs_entry *entry, | |
506 | char *buf) | |
507 | { | |
508 | return sprintf(buf, "%d\n", entry->position); | |
509 | } | |
510 | ||
511 | static DMI_SYSFS_ATTR(entry, length); | |
512 | static DMI_SYSFS_ATTR(entry, handle); | |
513 | static DMI_SYSFS_ATTR(entry, type); | |
514 | static DMI_SYSFS_ATTR(entry, instance); | |
515 | static DMI_SYSFS_ATTR(entry, position); | |
516 | ||
517 | static struct attribute *dmi_sysfs_entry_attrs[] = { | |
518 | &dmi_sysfs_attr_entry_length.attr, | |
519 | &dmi_sysfs_attr_entry_handle.attr, | |
520 | &dmi_sysfs_attr_entry_type.attr, | |
521 | &dmi_sysfs_attr_entry_instance.attr, | |
522 | &dmi_sysfs_attr_entry_position.attr, | |
523 | NULL, | |
524 | }; | |
ab6d0f57 | 525 | ATTRIBUTE_GROUPS(dmi_sysfs_entry); |
948af1f0 MW |
526 | |
527 | static ssize_t dmi_entry_raw_read_helper(struct dmi_sysfs_entry *entry, | |
528 | const struct dmi_header *dh, | |
529 | void *_state) | |
530 | { | |
531 | struct dmi_read_state *state = _state; | |
532 | size_t entry_length; | |
533 | ||
534 | entry_length = dmi_entry_length(dh); | |
535 | ||
536 | return memory_read_from_buffer(state->buf, state->count, | |
537 | &state->pos, dh, entry_length); | |
538 | } | |
539 | ||
540 | static ssize_t dmi_entry_raw_read(struct file *filp, | |
541 | struct kobject *kobj, | |
542 | struct bin_attribute *bin_attr, | |
543 | char *buf, loff_t pos, size_t count) | |
544 | { | |
545 | struct dmi_sysfs_entry *entry = to_entry(kobj); | |
546 | struct dmi_read_state state = { | |
547 | .buf = buf, | |
548 | .pos = pos, | |
549 | .count = count, | |
550 | }; | |
551 | ||
552 | return find_dmi_entry(entry, dmi_entry_raw_read_helper, &state); | |
553 | } | |
554 | ||
555 | static const struct bin_attribute dmi_entry_raw_attr = { | |
556 | .attr = {.name = "raw", .mode = 0400}, | |
557 | .read = dmi_entry_raw_read, | |
558 | }; | |
559 | ||
560 | static void dmi_sysfs_entry_release(struct kobject *kobj) | |
561 | { | |
562 | struct dmi_sysfs_entry *entry = to_entry(kobj); | |
a61aca28 | 563 | |
948af1f0 MW |
564 | spin_lock(&entry_list_lock); |
565 | list_del(&entry->list); | |
566 | spin_unlock(&entry_list_lock); | |
567 | kfree(entry); | |
568 | } | |
569 | ||
81773c98 | 570 | static const struct kobj_type dmi_sysfs_entry_ktype = { |
948af1f0 MW |
571 | .release = dmi_sysfs_entry_release, |
572 | .sysfs_ops = &dmi_sysfs_attr_ops, | |
ab6d0f57 | 573 | .default_groups = dmi_sysfs_entry_groups, |
948af1f0 MW |
574 | }; |
575 | ||
948af1f0 MW |
576 | static struct kset *dmi_kset; |
577 | ||
578 | /* Global count of all instances seen. Only for setup */ | |
579 | static int __initdata instance_counts[MAX_ENTRY_TYPE + 1]; | |
580 | ||
581 | /* Global positional count of all entries seen. Only for setup */ | |
582 | static int __initdata position_count; | |
583 | ||
584 | static void __init dmi_sysfs_register_handle(const struct dmi_header *dh, | |
585 | void *_ret) | |
586 | { | |
587 | struct dmi_sysfs_entry *entry; | |
588 | int *ret = _ret; | |
589 | ||
590 | /* If a previous entry saw an error, short circuit */ | |
591 | if (*ret) | |
592 | return; | |
593 | ||
594 | /* Allocate and register a new entry into the entries set */ | |
595 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | |
596 | if (!entry) { | |
597 | *ret = -ENOMEM; | |
598 | return; | |
599 | } | |
600 | ||
601 | /* Set the key */ | |
66245ad0 | 602 | memcpy(&entry->dh, dh, sizeof(*dh)); |
948af1f0 MW |
603 | entry->instance = instance_counts[dh->type]++; |
604 | entry->position = position_count++; | |
605 | ||
606 | entry->kobj.kset = dmi_kset; | |
607 | *ret = kobject_init_and_add(&entry->kobj, &dmi_sysfs_entry_ktype, NULL, | |
608 | "%d-%d", dh->type, entry->instance); | |
609 | ||
948af1f0 MW |
610 | /* Thread on the global list for cleanup */ |
611 | spin_lock(&entry_list_lock); | |
612 | list_add_tail(&entry->list, &entry_list); | |
613 | spin_unlock(&entry_list_lock); | |
614 | ||
18e126e9 CZ |
615 | if (*ret) { |
616 | kobject_put(&entry->kobj); | |
617 | return; | |
618 | } | |
619 | ||
925a1da7 MW |
620 | /* Handle specializations by type */ |
621 | switch (dh->type) { | |
622 | case DMI_ENTRY_SYSTEM_EVENT_LOG: | |
623 | *ret = dmi_system_event_log(entry); | |
624 | break; | |
625 | default: | |
626 | /* No specialization */ | |
627 | break; | |
628 | } | |
629 | if (*ret) | |
630 | goto out_err; | |
631 | ||
948af1f0 MW |
632 | /* Create the raw binary file to access the entry */ |
633 | *ret = sysfs_create_bin_file(&entry->kobj, &dmi_entry_raw_attr); | |
634 | if (*ret) | |
635 | goto out_err; | |
636 | ||
637 | return; | |
638 | out_err: | |
925a1da7 | 639 | kobject_put(entry->child); |
948af1f0 MW |
640 | kobject_put(&entry->kobj); |
641 | return; | |
642 | } | |
643 | ||
644 | static void cleanup_entry_list(void) | |
645 | { | |
646 | struct dmi_sysfs_entry *entry, *next; | |
647 | ||
648 | /* No locks, we are on our way out */ | |
649 | list_for_each_entry_safe(entry, next, &entry_list, list) { | |
925a1da7 | 650 | kobject_put(entry->child); |
948af1f0 MW |
651 | kobject_put(&entry->kobj); |
652 | } | |
653 | } | |
654 | ||
655 | static int __init dmi_sysfs_init(void) | |
656 | { | |
d7f96f97 | 657 | int error; |
948af1f0 MW |
658 | int val; |
659 | ||
d7f96f97 | 660 | if (!dmi_kobj) { |
a81114d0 | 661 | pr_debug("dmi-sysfs: dmi entry is absent.\n"); |
d7f96f97 | 662 | error = -ENODATA; |
948af1f0 | 663 | goto err; |
d7f96f97 | 664 | } |
948af1f0 MW |
665 | |
666 | dmi_kset = kset_create_and_add("entries", NULL, dmi_kobj); | |
d7f96f97 IK |
667 | if (!dmi_kset) { |
668 | error = -ENOMEM; | |
948af1f0 | 669 | goto err; |
d7f96f97 | 670 | } |
948af1f0 MW |
671 | |
672 | val = 0; | |
673 | error = dmi_walk(dmi_sysfs_register_handle, &val); | |
674 | if (error) | |
675 | goto err; | |
676 | if (val) { | |
677 | error = val; | |
678 | goto err; | |
679 | } | |
680 | ||
681 | pr_debug("dmi-sysfs: loaded.\n"); | |
682 | ||
683 | return 0; | |
684 | err: | |
685 | cleanup_entry_list(); | |
686 | kset_unregister(dmi_kset); | |
948af1f0 MW |
687 | return error; |
688 | } | |
689 | ||
690 | /* clean up everything. */ | |
691 | static void __exit dmi_sysfs_exit(void) | |
692 | { | |
693 | pr_debug("dmi-sysfs: unloading.\n"); | |
694 | cleanup_entry_list(); | |
695 | kset_unregister(dmi_kset); | |
948af1f0 MW |
696 | } |
697 | ||
698 | module_init(dmi_sysfs_init); | |
699 | module_exit(dmi_sysfs_exit); | |
700 | ||
701 | MODULE_AUTHOR("Mike Waychison <mikew@google.com>"); | |
702 | MODULE_DESCRIPTION("DMI sysfs support"); | |
703 | MODULE_LICENSE("GPL"); |