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