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Merge tag 'gpio-v3.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
[linux-2.6.git] / drivers / acpi / apei / erst.c
blob26311f23c824f91354b3e47fe6fa5e5e448275dc
1 /*
2 * APEI Error Record Serialization Table support
3 *
4 * ERST is a way provided by APEI to save and retrieve hardware error
5 * information to and from a persistent store.
6 *
7 * For more information about ERST, please refer to ACPI Specification
8 * version 4.0, section 17.4.
9 *
10 * Copyright 2010 Intel Corp.
11 * Author: Huang Ying <ying.huang@intel.com>
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License version
15 * 2 as published by the Free Software Foundation.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 */
26
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/delay.h>
31 #include <linux/io.h>
32 #include <linux/acpi.h>
33 #include <linux/uaccess.h>
34 #include <linux/cper.h>
35 #include <linux/nmi.h>
36 #include <linux/hardirq.h>
37 #include <linux/pstore.h>
38 #include <acpi/apei.h>
39
40 #include "apei-internal.h"
41
42 #undef pr_fmt
43 #define pr_fmt(fmt) "ERST: " fmt
44
45 /* ERST command status */
46 #define ERST_STATUS_SUCCESS 0x0
47 #define ERST_STATUS_NOT_ENOUGH_SPACE 0x1
48 #define ERST_STATUS_HARDWARE_NOT_AVAILABLE 0x2
49 #define ERST_STATUS_FAILED 0x3
50 #define ERST_STATUS_RECORD_STORE_EMPTY 0x4
51 #define ERST_STATUS_RECORD_NOT_FOUND 0x5
52
53 #define ERST_TAB_ENTRY(tab) \
54 ((struct acpi_whea_header *)((char *)(tab) + \
55 sizeof(struct acpi_table_erst)))
56
57 #define SPIN_UNIT 100 /* 100ns */
58 /* Firmware should respond within 1 milliseconds */
59 #define FIRMWARE_TIMEOUT (1 * NSEC_PER_MSEC)
60 #define FIRMWARE_MAX_STALL 50 /* 50us */
61
62 int erst_disable;
63 EXPORT_SYMBOL_GPL(erst_disable);
64
65 static struct acpi_table_erst *erst_tab;
66
67 /* ERST Error Log Address Range atrributes */
68 #define ERST_RANGE_RESERVED 0x0001
69 #define ERST_RANGE_NVRAM 0x0002
70 #define ERST_RANGE_SLOW 0x0004
71
72 /*
73 * ERST Error Log Address Range, used as buffer for reading/writing
74 * error records.
75 */
76 static struct erst_erange {
77 u64 base;
78 u64 size;
79 void __iomem *vaddr;
80 u32 attr;
81 } erst_erange;
82
83 /*
84 * Prevent ERST interpreter to run simultaneously, because the
85 * corresponding firmware implementation may not work properly when
86 * invoked simultaneously.
87 *
88 * It is used to provide exclusive accessing for ERST Error Log
89 * Address Range too.
90 */
91 static DEFINE_RAW_SPINLOCK(erst_lock);
92
93 static inline int erst_errno(int command_status)
94 {
95 switch (command_status) {
96 case ERST_STATUS_SUCCESS:
97 return 0;
98 case ERST_STATUS_HARDWARE_NOT_AVAILABLE:
99 return -ENODEV;
100 case ERST_STATUS_NOT_ENOUGH_SPACE:
101 return -ENOSPC;
102 case ERST_STATUS_RECORD_STORE_EMPTY:
103 case ERST_STATUS_RECORD_NOT_FOUND:
104 return -ENOENT;
105 default:
106 return -EINVAL;
107 }
108 }
109
110 static int erst_timedout(u64 *t, u64 spin_unit)
111 {
112 if ((s64)*t < spin_unit) {
113 pr_warn(FW_WARN "Firmware does not respond in time.\n");
114 return 1;
115 }
116 *t -= spin_unit;
117 ndelay(spin_unit);
118 touch_nmi_watchdog();
119 return 0;
120 }
121
122 static int erst_exec_load_var1(struct apei_exec_context *ctx,
123 struct acpi_whea_header *entry)
124 {
125 return __apei_exec_read_register(entry, &ctx->var1);
126 }
127
128 static int erst_exec_load_var2(struct apei_exec_context *ctx,
129 struct acpi_whea_header *entry)
130 {
131 return __apei_exec_read_register(entry, &ctx->var2);
132 }
133
134 static int erst_exec_store_var1(struct apei_exec_context *ctx,
135 struct acpi_whea_header *entry)
136 {
137 return __apei_exec_write_register(entry, ctx->var1);
138 }
139
140 static int erst_exec_add(struct apei_exec_context *ctx,
141 struct acpi_whea_header *entry)
142 {
143 ctx->var1 += ctx->var2;
144 return 0;
145 }
146
147 static int erst_exec_subtract(struct apei_exec_context *ctx,
148 struct acpi_whea_header *entry)
149 {
150 ctx->var1 -= ctx->var2;
151 return 0;
152 }
153
154 static int erst_exec_add_value(struct apei_exec_context *ctx,
155 struct acpi_whea_header *entry)
156 {
157 int rc;
158 u64 val;
159
160 rc = __apei_exec_read_register(entry, &val);
161 if (rc)
162 return rc;
163 val += ctx->value;
164 rc = __apei_exec_write_register(entry, val);
165 return rc;
166 }
167
168 static int erst_exec_subtract_value(struct apei_exec_context *ctx,
169 struct acpi_whea_header *entry)
170 {
171 int rc;
172 u64 val;
173
174 rc = __apei_exec_read_register(entry, &val);
175 if (rc)
176 return rc;
177 val -= ctx->value;
178 rc = __apei_exec_write_register(entry, val);
179 return rc;
180 }
181
182 static int erst_exec_stall(struct apei_exec_context *ctx,
183 struct acpi_whea_header *entry)
184 {
185 u64 stall_time;
186
187 if (ctx->value > FIRMWARE_MAX_STALL) {
188 if (!in_nmi())
189 pr_warn(FW_WARN
190 "Too long stall time for stall instruction: 0x%llx.\n",
191 ctx->value);
192 stall_time = FIRMWARE_MAX_STALL;
193 } else
194 stall_time = ctx->value;
195 udelay(stall_time);
196 return 0;
197 }
198
199 static int erst_exec_stall_while_true(struct apei_exec_context *ctx,
200 struct acpi_whea_header *entry)
201 {
202 int rc;
203 u64 val;
204 u64 timeout = FIRMWARE_TIMEOUT;
205 u64 stall_time;
206
207 if (ctx->var1 > FIRMWARE_MAX_STALL) {
208 if (!in_nmi())
209 pr_warn(FW_WARN
210 "Too long stall time for stall while true instruction: 0x%llx.\n",
211 ctx->var1);
212 stall_time = FIRMWARE_MAX_STALL;
213 } else
214 stall_time = ctx->var1;
215
216 for (;;) {
217 rc = __apei_exec_read_register(entry, &val);
218 if (rc)
219 return rc;
220 if (val != ctx->value)
221 break;
222 if (erst_timedout(&timeout, stall_time * NSEC_PER_USEC))
223 return -EIO;
224 }
225 return 0;
226 }
227
228 static int erst_exec_skip_next_instruction_if_true(
229 struct apei_exec_context *ctx,
230 struct acpi_whea_header *entry)
231 {
232 int rc;
233 u64 val;
234
235 rc = __apei_exec_read_register(entry, &val);
236 if (rc)
237 return rc;
238 if (val == ctx->value) {
239 ctx->ip += 2;
240 return APEI_EXEC_SET_IP;
241 }
242
243 return 0;
244 }
245
246 static int erst_exec_goto(struct apei_exec_context *ctx,
247 struct acpi_whea_header *entry)
248 {
249 ctx->ip = ctx->value;
250 return APEI_EXEC_SET_IP;
251 }
252
253 static int erst_exec_set_src_address_base(struct apei_exec_context *ctx,
254 struct acpi_whea_header *entry)
255 {
256 return __apei_exec_read_register(entry, &ctx->src_base);
257 }
258
259 static int erst_exec_set_dst_address_base(struct apei_exec_context *ctx,
260 struct acpi_whea_header *entry)
261 {
262 return __apei_exec_read_register(entry, &ctx->dst_base);
263 }
264
265 static int erst_exec_move_data(struct apei_exec_context *ctx,
266 struct acpi_whea_header *entry)
267 {
268 int rc;
269 u64 offset;
270 void *src, *dst;
271
272 /* ioremap does not work in interrupt context */
273 if (in_interrupt()) {
274 pr_warn("MOVE_DATA can not be used in interrupt context.\n");
275 return -EBUSY;
276 }
277
278 rc = __apei_exec_read_register(entry, &offset);
279 if (rc)
280 return rc;
281
282 src = ioremap(ctx->src_base + offset, ctx->var2);
283 if (!src)
284 return -ENOMEM;
285 dst = ioremap(ctx->dst_base + offset, ctx->var2);
286 if (!dst) {
287 iounmap(src);
288 return -ENOMEM;
289 }
290
291 memmove(dst, src, ctx->var2);
292
293 iounmap(src);
294 iounmap(dst);
295
296 return 0;
297 }
298
299 static struct apei_exec_ins_type erst_ins_type[] = {
300 [ACPI_ERST_READ_REGISTER] = {
301 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
302 .run = apei_exec_read_register,
303 },
304 [ACPI_ERST_READ_REGISTER_VALUE] = {
305 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
306 .run = apei_exec_read_register_value,
307 },
308 [ACPI_ERST_WRITE_REGISTER] = {
309 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
310 .run = apei_exec_write_register,
311 },
312 [ACPI_ERST_WRITE_REGISTER_VALUE] = {
313 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
314 .run = apei_exec_write_register_value,
315 },
316 [ACPI_ERST_NOOP] = {
317 .flags = 0,
318 .run = apei_exec_noop,
319 },
320 [ACPI_ERST_LOAD_VAR1] = {
321 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
322 .run = erst_exec_load_var1,
323 },
324 [ACPI_ERST_LOAD_VAR2] = {
325 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
326 .run = erst_exec_load_var2,
327 },
328 [ACPI_ERST_STORE_VAR1] = {
329 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
330 .run = erst_exec_store_var1,
331 },
332 [ACPI_ERST_ADD] = {
333 .flags = 0,
334 .run = erst_exec_add,
335 },
336 [ACPI_ERST_SUBTRACT] = {
337 .flags = 0,
338 .run = erst_exec_subtract,
339 },
340 [ACPI_ERST_ADD_VALUE] = {
341 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
342 .run = erst_exec_add_value,
343 },
344 [ACPI_ERST_SUBTRACT_VALUE] = {
345 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
346 .run = erst_exec_subtract_value,
347 },
348 [ACPI_ERST_STALL] = {
349 .flags = 0,
350 .run = erst_exec_stall,
351 },
352 [ACPI_ERST_STALL_WHILE_TRUE] = {
353 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
354 .run = erst_exec_stall_while_true,
355 },
356 [ACPI_ERST_SKIP_NEXT_IF_TRUE] = {
357 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
358 .run = erst_exec_skip_next_instruction_if_true,
359 },
360 [ACPI_ERST_GOTO] = {
361 .flags = 0,
362 .run = erst_exec_goto,
363 },
364 [ACPI_ERST_SET_SRC_ADDRESS_BASE] = {
365 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
366 .run = erst_exec_set_src_address_base,
367 },
368 [ACPI_ERST_SET_DST_ADDRESS_BASE] = {
369 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
370 .run = erst_exec_set_dst_address_base,
371 },
372 [ACPI_ERST_MOVE_DATA] = {
373 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
374 .run = erst_exec_move_data,
375 },
376 };
377
378 static inline void erst_exec_ctx_init(struct apei_exec_context *ctx)
379 {
380 apei_exec_ctx_init(ctx, erst_ins_type, ARRAY_SIZE(erst_ins_type),
381 ERST_TAB_ENTRY(erst_tab), erst_tab->entries);
382 }
383
384 static int erst_get_erange(struct erst_erange *range)
385 {
386 struct apei_exec_context ctx;
387 int rc;
388
389 erst_exec_ctx_init(&ctx);
390 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_RANGE);
391 if (rc)
392 return rc;
393 range->base = apei_exec_ctx_get_output(&ctx);
394 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_LENGTH);
395 if (rc)
396 return rc;
397 range->size = apei_exec_ctx_get_output(&ctx);
398 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_ATTRIBUTES);
399 if (rc)
400 return rc;
401 range->attr = apei_exec_ctx_get_output(&ctx);
402
403 return 0;
404 }
405
406 static ssize_t __erst_get_record_count(void)
407 {
408 struct apei_exec_context ctx;
409 int rc;
410
411 erst_exec_ctx_init(&ctx);
412 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_COUNT);
413 if (rc)
414 return rc;
415 return apei_exec_ctx_get_output(&ctx);
416 }
417
418 ssize_t erst_get_record_count(void)
419 {
420 ssize_t count;
421 unsigned long flags;
422
423 if (erst_disable)
424 return -ENODEV;
425
426 raw_spin_lock_irqsave(&erst_lock, flags);
427 count = __erst_get_record_count();
428 raw_spin_unlock_irqrestore(&erst_lock, flags);
429
430 return count;
431 }
432 EXPORT_SYMBOL_GPL(erst_get_record_count);
433
434 #define ERST_RECORD_ID_CACHE_SIZE_MIN 16
435 #define ERST_RECORD_ID_CACHE_SIZE_MAX 1024
436
437 struct erst_record_id_cache {
438 struct mutex lock;
439 u64 *entries;
440 int len;
441 int size;
442 int refcount;
443 };
444
445 static struct erst_record_id_cache erst_record_id_cache = {
446 .lock = __MUTEX_INITIALIZER(erst_record_id_cache.lock),
447 .refcount = 0,
448 };
449
450 static int __erst_get_next_record_id(u64 *record_id)
451 {
452 struct apei_exec_context ctx;
453 int rc;
454
455 erst_exec_ctx_init(&ctx);
456 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_ID);
457 if (rc)
458 return rc;
459 *record_id = apei_exec_ctx_get_output(&ctx);
460
461 return 0;
462 }
463
464 int erst_get_record_id_begin(int *pos)
465 {
466 int rc;
467
468 if (erst_disable)
469 return -ENODEV;
470
471 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);
472 if (rc)
473 return rc;
474 erst_record_id_cache.refcount++;
475 mutex_unlock(&erst_record_id_cache.lock);
476
477 *pos = 0;
478
479 return 0;
480 }
481 EXPORT_SYMBOL_GPL(erst_get_record_id_begin);
482
483 /* erst_record_id_cache.lock must be held by caller */
484 static int __erst_record_id_cache_add_one(void)
485 {
486 u64 id, prev_id, first_id;
487 int i, rc;
488 u64 *entries;
489 unsigned long flags;
490
491 id = prev_id = first_id = APEI_ERST_INVALID_RECORD_ID;
492 retry:
493 raw_spin_lock_irqsave(&erst_lock, flags);
494 rc = __erst_get_next_record_id(&id);
495 raw_spin_unlock_irqrestore(&erst_lock, flags);
496 if (rc == -ENOENT)
497 return 0;
498 if (rc)
499 return rc;
500 if (id == APEI_ERST_INVALID_RECORD_ID)
501 return 0;
502 /* can not skip current ID, or loop back to first ID */
503 if (id == prev_id || id == first_id)
504 return 0;
505 if (first_id == APEI_ERST_INVALID_RECORD_ID)
506 first_id = id;
507 prev_id = id;
508
509 entries = erst_record_id_cache.entries;
510 for (i = 0; i < erst_record_id_cache.len; i++) {
511 if (entries[i] == id)
512 break;
513 }
514 /* record id already in cache, try next */
515 if (i < erst_record_id_cache.len)
516 goto retry;
517 if (erst_record_id_cache.len >= erst_record_id_cache.size) {
518 int new_size, alloc_size;
519 u64 *new_entries;
520
521 new_size = erst_record_id_cache.size * 2;
522 new_size = clamp_val(new_size, ERST_RECORD_ID_CACHE_SIZE_MIN,
523 ERST_RECORD_ID_CACHE_SIZE_MAX);
524 if (new_size <= erst_record_id_cache.size) {
525 if (printk_ratelimit())
526 pr_warn(FW_WARN "too many record IDs!\n");
527 return 0;
528 }
529 alloc_size = new_size * sizeof(entries[0]);
530 if (alloc_size < PAGE_SIZE)
531 new_entries = kmalloc(alloc_size, GFP_KERNEL);
532 else
533 new_entries = vmalloc(alloc_size);
534 if (!new_entries)
535 return -ENOMEM;
536 memcpy(new_entries, entries,
537 erst_record_id_cache.len * sizeof(entries[0]));
538 if (erst_record_id_cache.size < PAGE_SIZE)
539 kfree(entries);
540 else
541 vfree(entries);
542 erst_record_id_cache.entries = entries = new_entries;
543 erst_record_id_cache.size = new_size;
544 }
545 entries[i] = id;
546 erst_record_id_cache.len++;
547
548 return 1;
549 }
550
551 /*
552 * Get the record ID of an existing error record on the persistent
553 * storage. If there is no error record on the persistent storage, the
554 * returned record_id is APEI_ERST_INVALID_RECORD_ID.
555 */
556 int erst_get_record_id_next(int *pos, u64 *record_id)
557 {
558 int rc = 0;
559 u64 *entries;
560
561 if (erst_disable)
562 return -ENODEV;
563
564 /* must be enclosed by erst_get_record_id_begin/end */
565 BUG_ON(!erst_record_id_cache.refcount);
566 BUG_ON(*pos < 0 || *pos > erst_record_id_cache.len);
567
568 mutex_lock(&erst_record_id_cache.lock);
569 entries = erst_record_id_cache.entries;
570 for (; *pos < erst_record_id_cache.len; (*pos)++)
571 if (entries[*pos] != APEI_ERST_INVALID_RECORD_ID)
572 break;
573 /* found next record id in cache */
574 if (*pos < erst_record_id_cache.len) {
575 *record_id = entries[*pos];
576 (*pos)++;
577 goto out_unlock;
578 }
579
580 /* Try to add one more record ID to cache */
581 rc = __erst_record_id_cache_add_one();
582 if (rc < 0)
583 goto out_unlock;
584 /* successfully add one new ID */
585 if (rc == 1) {
586 *record_id = erst_record_id_cache.entries[*pos];
587 (*pos)++;
588 rc = 0;
589 } else {
590 *pos = -1;
591 *record_id = APEI_ERST_INVALID_RECORD_ID;
592 }
593 out_unlock:
594 mutex_unlock(&erst_record_id_cache.lock);
595
596 return rc;
597 }
598 EXPORT_SYMBOL_GPL(erst_get_record_id_next);
599
600 /* erst_record_id_cache.lock must be held by caller */
601 static void __erst_record_id_cache_compact(void)
602 {
603 int i, wpos = 0;
604 u64 *entries;
605
606 if (erst_record_id_cache.refcount)
607 return;
608
609 entries = erst_record_id_cache.entries;
610 for (i = 0; i < erst_record_id_cache.len; i++) {
611 if (entries[i] == APEI_ERST_INVALID_RECORD_ID)
612 continue;
613 if (wpos != i)
614 memcpy(&entries[wpos], &entries[i], sizeof(entries[i]));
615 wpos++;
616 }
617 erst_record_id_cache.len = wpos;
618 }
619
620 void erst_get_record_id_end(void)
621 {
622 /*
623 * erst_disable != 0 should be detected by invoker via the
624 * return value of erst_get_record_id_begin/next, so this
625 * function should not be called for erst_disable != 0.
626 */
627 BUG_ON(erst_disable);
628
629 mutex_lock(&erst_record_id_cache.lock);
630 erst_record_id_cache.refcount--;
631 BUG_ON(erst_record_id_cache.refcount < 0);
632 __erst_record_id_cache_compact();
633 mutex_unlock(&erst_record_id_cache.lock);
634 }
635 EXPORT_SYMBOL_GPL(erst_get_record_id_end);
636
637 static int __erst_write_to_storage(u64 offset)
638 {
639 struct apei_exec_context ctx;
640 u64 timeout = FIRMWARE_TIMEOUT;
641 u64 val;
642 int rc;
643
644 erst_exec_ctx_init(&ctx);
645 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_WRITE);
646 if (rc)
647 return rc;
648 apei_exec_ctx_set_input(&ctx, offset);
649 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);
650 if (rc)
651 return rc;
652 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
653 if (rc)
654 return rc;
655 for (;;) {
656 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
657 if (rc)
658 return rc;
659 val = apei_exec_ctx_get_output(&ctx);
660 if (!val)
661 break;
662 if (erst_timedout(&timeout, SPIN_UNIT))
663 return -EIO;
664 }
665 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
666 if (rc)
667 return rc;
668 val = apei_exec_ctx_get_output(&ctx);
669 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
670 if (rc)
671 return rc;
672
673 return erst_errno(val);
674 }
675
676 static int __erst_read_from_storage(u64 record_id, u64 offset)
677 {
678 struct apei_exec_context ctx;
679 u64 timeout = FIRMWARE_TIMEOUT;
680 u64 val;
681 int rc;
682
683 erst_exec_ctx_init(&ctx);
684 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_READ);
685 if (rc)
686 return rc;
687 apei_exec_ctx_set_input(&ctx, offset);
688 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);
689 if (rc)
690 return rc;
691 apei_exec_ctx_set_input(&ctx, record_id);
692 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);
693 if (rc)
694 return rc;
695 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
696 if (rc)
697 return rc;
698 for (;;) {
699 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
700 if (rc)
701 return rc;
702 val = apei_exec_ctx_get_output(&ctx);
703 if (!val)
704 break;
705 if (erst_timedout(&timeout, SPIN_UNIT))
706 return -EIO;
707 };
708 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
709 if (rc)
710 return rc;
711 val = apei_exec_ctx_get_output(&ctx);
712 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
713 if (rc)
714 return rc;
715
716 return erst_errno(val);
717 }
718
719 static int __erst_clear_from_storage(u64 record_id)
720 {
721 struct apei_exec_context ctx;
722 u64 timeout = FIRMWARE_TIMEOUT;
723 u64 val;
724 int rc;
725
726 erst_exec_ctx_init(&ctx);
727 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_CLEAR);
728 if (rc)
729 return rc;
730 apei_exec_ctx_set_input(&ctx, record_id);
731 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);
732 if (rc)
733 return rc;
734 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
735 if (rc)
736 return rc;
737 for (;;) {
738 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
739 if (rc)
740 return rc;
741 val = apei_exec_ctx_get_output(&ctx);
742 if (!val)
743 break;
744 if (erst_timedout(&timeout, SPIN_UNIT))
745 return -EIO;
746 }
747 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
748 if (rc)
749 return rc;
750 val = apei_exec_ctx_get_output(&ctx);
751 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
752 if (rc)
753 return rc;
754
755 return erst_errno(val);
756 }
757
758 /* NVRAM ERST Error Log Address Range is not supported yet */
759 static void pr_unimpl_nvram(void)
760 {
761 if (printk_ratelimit())
762 pr_warn("NVRAM ERST Log Address Range not implemented yet.\n");
763 }
764
765 static int __erst_write_to_nvram(const struct cper_record_header *record)
766 {
767 /* do not print message, because printk is not safe for NMI */
768 return -ENOSYS;
769 }
770
771 static int __erst_read_to_erange_from_nvram(u64 record_id, u64 *offset)
772 {
773 pr_unimpl_nvram();
774 return -ENOSYS;
775 }
776
777 static int __erst_clear_from_nvram(u64 record_id)
778 {
779 pr_unimpl_nvram();
780 return -ENOSYS;
781 }
782
783 int erst_write(const struct cper_record_header *record)
784 {
785 int rc;
786 unsigned long flags;
787 struct cper_record_header *rcd_erange;
788
789 if (erst_disable)
790 return -ENODEV;
791
792 if (memcmp(record->signature, CPER_SIG_RECORD, CPER_SIG_SIZE))
793 return -EINVAL;
794
795 if (erst_erange.attr & ERST_RANGE_NVRAM) {
796 if (!raw_spin_trylock_irqsave(&erst_lock, flags))
797 return -EBUSY;
798 rc = __erst_write_to_nvram(record);
799 raw_spin_unlock_irqrestore(&erst_lock, flags);
800 return rc;
801 }
802
803 if (record->record_length > erst_erange.size)
804 return -EINVAL;
805
806 if (!raw_spin_trylock_irqsave(&erst_lock, flags))
807 return -EBUSY;
808 memcpy(erst_erange.vaddr, record, record->record_length);
809 rcd_erange = erst_erange.vaddr;
810 /* signature for serialization system */
811 memcpy(&rcd_erange->persistence_information, "ER", 2);
812
813 rc = __erst_write_to_storage(0);
814 raw_spin_unlock_irqrestore(&erst_lock, flags);
815
816 return rc;
817 }
818 EXPORT_SYMBOL_GPL(erst_write);
819
820 static int __erst_read_to_erange(u64 record_id, u64 *offset)
821 {
822 int rc;
823
824 if (erst_erange.attr & ERST_RANGE_NVRAM)
825 return __erst_read_to_erange_from_nvram(
826 record_id, offset);
827
828 rc = __erst_read_from_storage(record_id, 0);
829 if (rc)
830 return rc;
831 *offset = 0;
832
833 return 0;
834 }
835
836 static ssize_t __erst_read(u64 record_id, struct cper_record_header *record,
837 size_t buflen)
838 {
839 int rc;
840 u64 offset, len = 0;
841 struct cper_record_header *rcd_tmp;
842
843 rc = __erst_read_to_erange(record_id, &offset);
844 if (rc)
845 return rc;
846 rcd_tmp = erst_erange.vaddr + offset;
847 len = rcd_tmp->record_length;
848 if (len <= buflen)
849 memcpy(record, rcd_tmp, len);
850
851 return len;
852 }
853
854 /*
855 * If return value > buflen, the buffer size is not big enough,
856 * else if return value < 0, something goes wrong,
857 * else everything is OK, and return value is record length
858 */
859 ssize_t erst_read(u64 record_id, struct cper_record_header *record,
860 size_t buflen)
861 {
862 ssize_t len;
863 unsigned long flags;
864
865 if (erst_disable)
866 return -ENODEV;
867
868 raw_spin_lock_irqsave(&erst_lock, flags);
869 len = __erst_read(record_id, record, buflen);
870 raw_spin_unlock_irqrestore(&erst_lock, flags);
871 return len;
872 }
873 EXPORT_SYMBOL_GPL(erst_read);
874
875 int erst_clear(u64 record_id)
876 {
877 int rc, i;
878 unsigned long flags;
879 u64 *entries;
880
881 if (erst_disable)
882 return -ENODEV;
883
884 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);
885 if (rc)
886 return rc;
887 raw_spin_lock_irqsave(&erst_lock, flags);
888 if (erst_erange.attr & ERST_RANGE_NVRAM)
889 rc = __erst_clear_from_nvram(record_id);
890 else
891 rc = __erst_clear_from_storage(record_id);
892 raw_spin_unlock_irqrestore(&erst_lock, flags);
893 if (rc)
894 goto out;
895 entries = erst_record_id_cache.entries;
896 for (i = 0; i < erst_record_id_cache.len; i++) {
897 if (entries[i] == record_id)
898 entries[i] = APEI_ERST_INVALID_RECORD_ID;
899 }
900 __erst_record_id_cache_compact();
901 out:
902 mutex_unlock(&erst_record_id_cache.lock);
903 return rc;
904 }
905 EXPORT_SYMBOL_GPL(erst_clear);
906
907 static int __init setup_erst_disable(char *str)
908 {
909 erst_disable = 1;
910 return 0;
911 }
912
913 __setup("erst_disable", setup_erst_disable);
914
915 static int erst_check_table(struct acpi_table_erst *erst_tab)
916 {
917 if ((erst_tab->header_length !=
918 (sizeof(struct acpi_table_erst) - sizeof(erst_tab->header)))
919 && (erst_tab->header_length != sizeof(struct acpi_table_erst)))
920 return -EINVAL;
921 if (erst_tab->header.length < sizeof(struct acpi_table_erst))
922 return -EINVAL;
923 if (erst_tab->entries !=
924 (erst_tab->header.length - sizeof(struct acpi_table_erst)) /
925 sizeof(struct acpi_erst_entry))
926 return -EINVAL;
927
928 return 0;
929 }
930
931 static int erst_open_pstore(struct pstore_info *psi);
932 static int erst_close_pstore(struct pstore_info *psi);
933 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
934 struct timespec *time, char **buf,
935 bool *compressed, struct pstore_info *psi);
936 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
937 u64 *id, unsigned int part, int count, bool compressed,
938 size_t size, struct pstore_info *psi);
939 static int erst_clearer(enum pstore_type_id type, u64 id, int count,
940 struct timespec time, struct pstore_info *psi);
941
942 static struct pstore_info erst_info = {
943 .owner = THIS_MODULE,
944 .name = "erst",
945 .open = erst_open_pstore,
946 .close = erst_close_pstore,
947 .read = erst_reader,
948 .write = erst_writer,
949 .erase = erst_clearer
950 };
951
952 #define CPER_CREATOR_PSTORE \
953 UUID_LE(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c, \
954 0x64, 0x90, 0xb8, 0x9d)
955 #define CPER_SECTION_TYPE_DMESG \
956 UUID_LE(0xc197e04e, 0xd545, 0x4a70, 0x9c, 0x17, 0xa5, 0x54, \
957 0x94, 0x19, 0xeb, 0x12)
958 #define CPER_SECTION_TYPE_DMESG_Z \
959 UUID_LE(0x4f118707, 0x04dd, 0x4055, 0xb5, 0xdd, 0x95, 0x6d, \
960 0x34, 0xdd, 0xfa, 0xc6)
961 #define CPER_SECTION_TYPE_MCE \
962 UUID_LE(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96, \
963 0x04, 0x4a, 0x38, 0xfc)
964
965 struct cper_pstore_record {
966 struct cper_record_header hdr;
967 struct cper_section_descriptor sec_hdr;
968 char data[];
969 } __packed;
970
971 static int reader_pos;
972
973 static int erst_open_pstore(struct pstore_info *psi)
974 {
975 int rc;
976
977 if (erst_disable)
978 return -ENODEV;
979
980 rc = erst_get_record_id_begin(&reader_pos);
981
982 return rc;
983 }
984
985 static int erst_close_pstore(struct pstore_info *psi)
986 {
987 erst_get_record_id_end();
988
989 return 0;
990 }
991
992 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
993 struct timespec *time, char **buf,
994 bool *compressed, struct pstore_info *psi)
995 {
996 int rc;
997 ssize_t len = 0;
998 u64 record_id;
999 struct cper_pstore_record *rcd;
1000 size_t rcd_len = sizeof(*rcd) + erst_info.bufsize;
1001
1002 if (erst_disable)
1003 return -ENODEV;
1004
1005 rcd = kmalloc(rcd_len, GFP_KERNEL);
1006 if (!rcd) {
1007 rc = -ENOMEM;
1008 goto out;
1009 }
1010 skip:
1011 rc = erst_get_record_id_next(&reader_pos, &record_id);
1012 if (rc)
1013 goto out;
1014
1015 /* no more record */
1016 if (record_id == APEI_ERST_INVALID_RECORD_ID) {
1017 rc = -EINVAL;
1018 goto out;
1019 }
1020
1021 len = erst_read(record_id, &rcd->hdr, rcd_len);
1022 /* The record may be cleared by others, try read next record */
1023 if (len == -ENOENT)
1024 goto skip;
1025 else if (len < sizeof(*rcd)) {
1026 rc = -EIO;
1027 goto out;
1028 }
1029 if (uuid_le_cmp(rcd->hdr.creator_id, CPER_CREATOR_PSTORE) != 0)
1030 goto skip;
1031
1032 *buf = kmalloc(len, GFP_KERNEL);
1033 if (*buf == NULL) {
1034 rc = -ENOMEM;
1035 goto out;
1036 }
1037 memcpy(*buf, rcd->data, len - sizeof(*rcd));
1038 *id = record_id;
1039 *compressed = false;
1040 if (uuid_le_cmp(rcd->sec_hdr.section_type,
1041 CPER_SECTION_TYPE_DMESG_Z) == 0) {
1042 *type = PSTORE_TYPE_DMESG;
1043 *compressed = true;
1044 } else if (uuid_le_cmp(rcd->sec_hdr.section_type,
1045 CPER_SECTION_TYPE_DMESG) == 0)
1046 *type = PSTORE_TYPE_DMESG;
1047 else if (uuid_le_cmp(rcd->sec_hdr.section_type,
1048 CPER_SECTION_TYPE_MCE) == 0)
1049 *type = PSTORE_TYPE_MCE;
1050 else
1051 *type = PSTORE_TYPE_UNKNOWN;
1052
1053 if (rcd->hdr.validation_bits & CPER_VALID_TIMESTAMP)
1054 time->tv_sec = rcd->hdr.timestamp;
1055 else
1056 time->tv_sec = 0;
1057 time->tv_nsec = 0;
1058
1059 out:
1060 kfree(rcd);
1061 return (rc < 0) ? rc : (len - sizeof(*rcd));
1062 }
1063
1064 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
1065 u64 *id, unsigned int part, int count, bool compressed,
1066 size_t size, struct pstore_info *psi)
1067 {
1068 struct cper_pstore_record *rcd = (struct cper_pstore_record *)
1069 (erst_info.buf - sizeof(*rcd));
1070 int ret;
1071
1072 memset(rcd, 0, sizeof(*rcd));
1073 memcpy(rcd->hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE);
1074 rcd->hdr.revision = CPER_RECORD_REV;
1075 rcd->hdr.signature_end = CPER_SIG_END;
1076 rcd->hdr.section_count = 1;
1077 rcd->hdr.error_severity = CPER_SEV_FATAL;
1078 /* timestamp valid. platform_id, partition_id are invalid */
1079 rcd->hdr.validation_bits = CPER_VALID_TIMESTAMP;
1080 rcd->hdr.timestamp = get_seconds();
1081 rcd->hdr.record_length = sizeof(*rcd) + size;
1082 rcd->hdr.creator_id = CPER_CREATOR_PSTORE;
1083 rcd->hdr.notification_type = CPER_NOTIFY_MCE;
1084 rcd->hdr.record_id = cper_next_record_id();
1085 rcd->hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR;
1086
1087 rcd->sec_hdr.section_offset = sizeof(*rcd);
1088 rcd->sec_hdr.section_length = size;
1089 rcd->sec_hdr.revision = CPER_SEC_REV;
1090 /* fru_id and fru_text is invalid */
1091 rcd->sec_hdr.validation_bits = 0;
1092 rcd->sec_hdr.flags = CPER_SEC_PRIMARY;
1093 switch (type) {
1094 case PSTORE_TYPE_DMESG:
1095 if (compressed)
1096 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG_Z;
1097 else
1098 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG;
1099 break;
1100 case PSTORE_TYPE_MCE:
1101 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_MCE;
1102 break;
1103 default:
1104 return -EINVAL;
1105 }
1106 rcd->sec_hdr.section_severity = CPER_SEV_FATAL;
1107
1108 ret = erst_write(&rcd->hdr);
1109 *id = rcd->hdr.record_id;
1110
1111 return ret;
1112 }
1113
1114 static int erst_clearer(enum pstore_type_id type, u64 id, int count,
1115 struct timespec time, struct pstore_info *psi)
1116 {
1117 return erst_clear(id);
1118 }
1119
1120 static int __init erst_init(void)
1121 {
1122 int rc = 0;
1123 acpi_status status;
1124 struct apei_exec_context ctx;
1125 struct apei_resources erst_resources;
1126 struct resource *r;
1127 char *buf;
1128
1129 if (acpi_disabled)
1130 goto err;
1131
1132 if (erst_disable) {
1133 pr_info(
1134 "Error Record Serialization Table (ERST) support is disabled.\n");
1135 goto err;
1136 }
1137
1138 status = acpi_get_table(ACPI_SIG_ERST, 0,
1139 (struct acpi_table_header **)&erst_tab);
1140 if (status == AE_NOT_FOUND)
1141 goto err;
1142 else if (ACPI_FAILURE(status)) {
1143 const char *msg = acpi_format_exception(status);
1144 pr_err("Failed to get table, %s\n", msg);
1145 rc = -EINVAL;
1146 goto err;
1147 }
1148
1149 rc = erst_check_table(erst_tab);
1150 if (rc) {
1151 pr_err(FW_BUG "ERST table is invalid.\n");
1152 goto err;
1153 }
1154
1155 apei_resources_init(&erst_resources);
1156 erst_exec_ctx_init(&ctx);
1157 rc = apei_exec_collect_resources(&ctx, &erst_resources);
1158 if (rc)
1159 goto err_fini;
1160 rc = apei_resources_request(&erst_resources, "APEI ERST");
1161 if (rc)
1162 goto err_fini;
1163 rc = apei_exec_pre_map_gars(&ctx);
1164 if (rc)
1165 goto err_release;
1166 rc = erst_get_erange(&erst_erange);
1167 if (rc) {
1168 if (rc == -ENODEV)
1169 pr_info(
1170 "The corresponding hardware device or firmware implementation "
1171 "is not available.\n");
1172 else
1173 pr_err("Failed to get Error Log Address Range.\n");
1174 goto err_unmap_reg;
1175 }
1176
1177 r = request_mem_region(erst_erange.base, erst_erange.size, "APEI ERST");
1178 if (!r) {
1179 pr_err("Can not request [mem %#010llx-%#010llx] for ERST.\n",
1180 (unsigned long long)erst_erange.base,
1181 (unsigned long long)erst_erange.base + erst_erange.size - 1);
1182 rc = -EIO;
1183 goto err_unmap_reg;
1184 }
1185 rc = -ENOMEM;
1186 erst_erange.vaddr = ioremap_cache(erst_erange.base,
1187 erst_erange.size);
1188 if (!erst_erange.vaddr)
1189 goto err_release_erange;
1190
1191 pr_info(
1192 "Error Record Serialization Table (ERST) support is initialized.\n");
1193
1194 buf = kmalloc(erst_erange.size, GFP_KERNEL);
1195 spin_lock_init(&erst_info.buf_lock);
1196 if (buf) {
1197 erst_info.buf = buf + sizeof(struct cper_pstore_record);
1198 erst_info.bufsize = erst_erange.size -
1199 sizeof(struct cper_pstore_record);
1200 rc = pstore_register(&erst_info);
1201 if (rc) {
1202 if (rc != -EPERM)
1203 pr_info(
1204 "Could not register with persistent store.\n");
1205 erst_info.buf = NULL;
1206 erst_info.bufsize = 0;
1207 kfree(buf);
1208 }
1209 } else
1210 pr_err(
1211 "Failed to allocate %lld bytes for persistent store error log.\n",
1212 erst_erange.size);
1213
1214 return 0;
1215
1216 err_release_erange:
1217 release_mem_region(erst_erange.base, erst_erange.size);
1218 err_unmap_reg:
1219 apei_exec_post_unmap_gars(&ctx);
1220 err_release:
1221 apei_resources_release(&erst_resources);
1222 err_fini:
1223 apei_resources_fini(&erst_resources);
1224 err:
1225 erst_disable = 1;
1226 return rc;
1227 }
1228
1229 device_initcall(erst_init);
Linus' kernel tree