Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
[linux-2.6.git] / drivers / acpi / apei / erst.c
blob88d0b0f9f92b73706e330e62a4bcf70dd4b0befa
1 /*
2 * APEI Error Record Serialization Table support
4 * ERST is a way provided by APEI to save and retrieve hardware error
5 * information to and from a persistent store.
7 * For more information about ERST, please refer to ACPI Specification
8 * version 4.0, section 17.4.
10 * Copyright 2010 Intel Corp.
11 * Author: Huang Ying <ying.huang@intel.com>
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.
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.
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
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>
40 #include "apei-internal.h"
42 #define ERST_PFX "ERST: "
44 /* ERST command status */
45 #define ERST_STATUS_SUCCESS 0x0
46 #define ERST_STATUS_NOT_ENOUGH_SPACE 0x1
47 #define ERST_STATUS_HARDWARE_NOT_AVAILABLE 0x2
48 #define ERST_STATUS_FAILED 0x3
49 #define ERST_STATUS_RECORD_STORE_EMPTY 0x4
50 #define ERST_STATUS_RECORD_NOT_FOUND 0x5
52 #define ERST_TAB_ENTRY(tab) \
53 ((struct acpi_whea_header *)((char *)(tab) + \
54 sizeof(struct acpi_table_erst)))
56 #define SPIN_UNIT 100 /* 100ns */
57 /* Firmware should respond within 1 milliseconds */
58 #define FIRMWARE_TIMEOUT (1 * NSEC_PER_MSEC)
59 #define FIRMWARE_MAX_STALL 50 /* 50us */
61 int erst_disable;
62 EXPORT_SYMBOL_GPL(erst_disable);
64 static struct acpi_table_erst *erst_tab;
66 /* ERST Error Log Address Range atrributes */
67 #define ERST_RANGE_RESERVED 0x0001
68 #define ERST_RANGE_NVRAM 0x0002
69 #define ERST_RANGE_SLOW 0x0004
72 * ERST Error Log Address Range, used as buffer for reading/writing
73 * error records.
75 static struct erst_erange {
76 u64 base;
77 u64 size;
78 void __iomem *vaddr;
79 u32 attr;
80 } erst_erange;
83 * Prevent ERST interpreter to run simultaneously, because the
84 * corresponding firmware implementation may not work properly when
85 * invoked simultaneously.
87 * It is used to provide exclusive accessing for ERST Error Log
88 * Address Range too.
90 static DEFINE_RAW_SPINLOCK(erst_lock);
92 static inline int erst_errno(int command_status)
94 switch (command_status) {
95 case ERST_STATUS_SUCCESS:
96 return 0;
97 case ERST_STATUS_HARDWARE_NOT_AVAILABLE:
98 return -ENODEV;
99 case ERST_STATUS_NOT_ENOUGH_SPACE:
100 return -ENOSPC;
101 case ERST_STATUS_RECORD_STORE_EMPTY:
102 case ERST_STATUS_RECORD_NOT_FOUND:
103 return -ENOENT;
104 default:
105 return -EINVAL;
109 static int erst_timedout(u64 *t, u64 spin_unit)
111 if ((s64)*t < spin_unit) {
112 pr_warning(FW_WARN ERST_PFX
113 "Firmware does not respond in time\n");
114 return 1;
116 *t -= spin_unit;
117 ndelay(spin_unit);
118 touch_nmi_watchdog();
119 return 0;
122 static int erst_exec_load_var1(struct apei_exec_context *ctx,
123 struct acpi_whea_header *entry)
125 return __apei_exec_read_register(entry, &ctx->var1);
128 static int erst_exec_load_var2(struct apei_exec_context *ctx,
129 struct acpi_whea_header *entry)
131 return __apei_exec_read_register(entry, &ctx->var2);
134 static int erst_exec_store_var1(struct apei_exec_context *ctx,
135 struct acpi_whea_header *entry)
137 return __apei_exec_write_register(entry, ctx->var1);
140 static int erst_exec_add(struct apei_exec_context *ctx,
141 struct acpi_whea_header *entry)
143 ctx->var1 += ctx->var2;
144 return 0;
147 static int erst_exec_subtract(struct apei_exec_context *ctx,
148 struct acpi_whea_header *entry)
150 ctx->var1 -= ctx->var2;
151 return 0;
154 static int erst_exec_add_value(struct apei_exec_context *ctx,
155 struct acpi_whea_header *entry)
157 int rc;
158 u64 val;
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;
168 static int erst_exec_subtract_value(struct apei_exec_context *ctx,
169 struct acpi_whea_header *entry)
171 int rc;
172 u64 val;
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;
182 static int erst_exec_stall(struct apei_exec_context *ctx,
183 struct acpi_whea_header *entry)
185 u64 stall_time;
187 if (ctx->value > FIRMWARE_MAX_STALL) {
188 if (!in_nmi())
189 pr_warning(FW_WARN ERST_PFX
190 "Too long stall time for stall instruction: %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;
199 static int erst_exec_stall_while_true(struct apei_exec_context *ctx,
200 struct acpi_whea_header *entry)
202 int rc;
203 u64 val;
204 u64 timeout = FIRMWARE_TIMEOUT;
205 u64 stall_time;
207 if (ctx->var1 > FIRMWARE_MAX_STALL) {
208 if (!in_nmi())
209 pr_warning(FW_WARN ERST_PFX
210 "Too long stall time for stall while true instruction: %llx.\n",
211 ctx->var1);
212 stall_time = FIRMWARE_MAX_STALL;
213 } else
214 stall_time = ctx->var1;
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;
225 return 0;
228 static int erst_exec_skip_next_instruction_if_true(
229 struct apei_exec_context *ctx,
230 struct acpi_whea_header *entry)
232 int rc;
233 u64 val;
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;
243 return 0;
246 static int erst_exec_goto(struct apei_exec_context *ctx,
247 struct acpi_whea_header *entry)
249 ctx->ip = ctx->value;
250 return APEI_EXEC_SET_IP;
253 static int erst_exec_set_src_address_base(struct apei_exec_context *ctx,
254 struct acpi_whea_header *entry)
256 return __apei_exec_read_register(entry, &ctx->src_base);
259 static int erst_exec_set_dst_address_base(struct apei_exec_context *ctx,
260 struct acpi_whea_header *entry)
262 return __apei_exec_read_register(entry, &ctx->dst_base);
265 static int erst_exec_move_data(struct apei_exec_context *ctx,
266 struct acpi_whea_header *entry)
268 int rc;
269 u64 offset;
270 void *src, *dst;
272 /* ioremap does not work in interrupt context */
273 if (in_interrupt()) {
274 pr_warning(ERST_PFX
275 "MOVE_DATA can not be used in interrupt context");
276 return -EBUSY;
279 rc = __apei_exec_read_register(entry, &offset);
280 if (rc)
281 return rc;
283 src = ioremap(ctx->src_base + offset, ctx->var2);
284 if (!src)
285 return -ENOMEM;
286 dst = ioremap(ctx->dst_base + offset, ctx->var2);
287 if (!dst)
288 return -ENOMEM;
290 memmove(dst, src, ctx->var2);
292 iounmap(src);
293 iounmap(dst);
295 return 0;
298 static struct apei_exec_ins_type erst_ins_type[] = {
299 [ACPI_ERST_READ_REGISTER] = {
300 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
301 .run = apei_exec_read_register,
303 [ACPI_ERST_READ_REGISTER_VALUE] = {
304 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
305 .run = apei_exec_read_register_value,
307 [ACPI_ERST_WRITE_REGISTER] = {
308 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
309 .run = apei_exec_write_register,
311 [ACPI_ERST_WRITE_REGISTER_VALUE] = {
312 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
313 .run = apei_exec_write_register_value,
315 [ACPI_ERST_NOOP] = {
316 .flags = 0,
317 .run = apei_exec_noop,
319 [ACPI_ERST_LOAD_VAR1] = {
320 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
321 .run = erst_exec_load_var1,
323 [ACPI_ERST_LOAD_VAR2] = {
324 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
325 .run = erst_exec_load_var2,
327 [ACPI_ERST_STORE_VAR1] = {
328 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
329 .run = erst_exec_store_var1,
331 [ACPI_ERST_ADD] = {
332 .flags = 0,
333 .run = erst_exec_add,
335 [ACPI_ERST_SUBTRACT] = {
336 .flags = 0,
337 .run = erst_exec_subtract,
339 [ACPI_ERST_ADD_VALUE] = {
340 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
341 .run = erst_exec_add_value,
343 [ACPI_ERST_SUBTRACT_VALUE] = {
344 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
345 .run = erst_exec_subtract_value,
347 [ACPI_ERST_STALL] = {
348 .flags = 0,
349 .run = erst_exec_stall,
351 [ACPI_ERST_STALL_WHILE_TRUE] = {
352 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
353 .run = erst_exec_stall_while_true,
355 [ACPI_ERST_SKIP_NEXT_IF_TRUE] = {
356 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
357 .run = erst_exec_skip_next_instruction_if_true,
359 [ACPI_ERST_GOTO] = {
360 .flags = 0,
361 .run = erst_exec_goto,
363 [ACPI_ERST_SET_SRC_ADDRESS_BASE] = {
364 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
365 .run = erst_exec_set_src_address_base,
367 [ACPI_ERST_SET_DST_ADDRESS_BASE] = {
368 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
369 .run = erst_exec_set_dst_address_base,
371 [ACPI_ERST_MOVE_DATA] = {
372 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
373 .run = erst_exec_move_data,
377 static inline void erst_exec_ctx_init(struct apei_exec_context *ctx)
379 apei_exec_ctx_init(ctx, erst_ins_type, ARRAY_SIZE(erst_ins_type),
380 ERST_TAB_ENTRY(erst_tab), erst_tab->entries);
383 static int erst_get_erange(struct erst_erange *range)
385 struct apei_exec_context ctx;
386 int rc;
388 erst_exec_ctx_init(&ctx);
389 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_RANGE);
390 if (rc)
391 return rc;
392 range->base = apei_exec_ctx_get_output(&ctx);
393 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_LENGTH);
394 if (rc)
395 return rc;
396 range->size = apei_exec_ctx_get_output(&ctx);
397 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_ATTRIBUTES);
398 if (rc)
399 return rc;
400 range->attr = apei_exec_ctx_get_output(&ctx);
402 return 0;
405 static ssize_t __erst_get_record_count(void)
407 struct apei_exec_context ctx;
408 int rc;
410 erst_exec_ctx_init(&ctx);
411 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_COUNT);
412 if (rc)
413 return rc;
414 return apei_exec_ctx_get_output(&ctx);
417 ssize_t erst_get_record_count(void)
419 ssize_t count;
420 unsigned long flags;
422 if (erst_disable)
423 return -ENODEV;
425 raw_spin_lock_irqsave(&erst_lock, flags);
426 count = __erst_get_record_count();
427 raw_spin_unlock_irqrestore(&erst_lock, flags);
429 return count;
431 EXPORT_SYMBOL_GPL(erst_get_record_count);
433 #define ERST_RECORD_ID_CACHE_SIZE_MIN 16
434 #define ERST_RECORD_ID_CACHE_SIZE_MAX 1024
436 struct erst_record_id_cache {
437 struct mutex lock;
438 u64 *entries;
439 int len;
440 int size;
441 int refcount;
444 static struct erst_record_id_cache erst_record_id_cache = {
445 .lock = __MUTEX_INITIALIZER(erst_record_id_cache.lock),
446 .refcount = 0,
449 static int __erst_get_next_record_id(u64 *record_id)
451 struct apei_exec_context ctx;
452 int rc;
454 erst_exec_ctx_init(&ctx);
455 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_ID);
456 if (rc)
457 return rc;
458 *record_id = apei_exec_ctx_get_output(&ctx);
460 return 0;
463 int erst_get_record_id_begin(int *pos)
465 int rc;
467 if (erst_disable)
468 return -ENODEV;
470 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);
471 if (rc)
472 return rc;
473 erst_record_id_cache.refcount++;
474 mutex_unlock(&erst_record_id_cache.lock);
476 *pos = 0;
478 return 0;
480 EXPORT_SYMBOL_GPL(erst_get_record_id_begin);
482 /* erst_record_id_cache.lock must be held by caller */
483 static int __erst_record_id_cache_add_one(void)
485 u64 id, prev_id, first_id;
486 int i, rc;
487 u64 *entries;
488 unsigned long flags;
490 id = prev_id = first_id = APEI_ERST_INVALID_RECORD_ID;
491 retry:
492 raw_spin_lock_irqsave(&erst_lock, flags);
493 rc = __erst_get_next_record_id(&id);
494 raw_spin_unlock_irqrestore(&erst_lock, flags);
495 if (rc == -ENOENT)
496 return 0;
497 if (rc)
498 return rc;
499 if (id == APEI_ERST_INVALID_RECORD_ID)
500 return 0;
501 /* can not skip current ID, or loop back to first ID */
502 if (id == prev_id || id == first_id)
503 return 0;
504 if (first_id == APEI_ERST_INVALID_RECORD_ID)
505 first_id = id;
506 prev_id = id;
508 entries = erst_record_id_cache.entries;
509 for (i = 0; i < erst_record_id_cache.len; i++) {
510 if (entries[i] == id)
511 break;
513 /* record id already in cache, try next */
514 if (i < erst_record_id_cache.len)
515 goto retry;
516 if (erst_record_id_cache.len >= erst_record_id_cache.size) {
517 int new_size, alloc_size;
518 u64 *new_entries;
520 new_size = erst_record_id_cache.size * 2;
521 new_size = clamp_val(new_size, ERST_RECORD_ID_CACHE_SIZE_MIN,
522 ERST_RECORD_ID_CACHE_SIZE_MAX);
523 if (new_size <= erst_record_id_cache.size) {
524 if (printk_ratelimit())
525 pr_warning(FW_WARN ERST_PFX
526 "too many record ID!\n");
527 return 0;
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;
545 entries[i] = id;
546 erst_record_id_cache.len++;
548 return 1;
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.
556 int erst_get_record_id_next(int *pos, u64 *record_id)
558 int rc = 0;
559 u64 *entries;
561 if (erst_disable)
562 return -ENODEV;
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);
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;
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;
593 out_unlock:
594 mutex_unlock(&erst_record_id_cache.lock);
596 return rc;
598 EXPORT_SYMBOL_GPL(erst_get_record_id_next);
600 /* erst_record_id_cache.lock must be held by caller */
601 static void __erst_record_id_cache_compact(void)
603 int i, wpos = 0;
604 u64 *entries;
606 if (erst_record_id_cache.refcount)
607 return;
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++;
617 erst_record_id_cache.len = wpos;
620 void erst_get_record_id_end(void)
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.
627 BUG_ON(erst_disable);
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);
635 EXPORT_SYMBOL_GPL(erst_get_record_id_end);
637 static int __erst_write_to_storage(u64 offset)
639 struct apei_exec_context ctx;
640 u64 timeout = FIRMWARE_TIMEOUT;
641 u64 val;
642 int rc;
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;
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;
673 return erst_errno(val);
676 static int __erst_read_from_storage(u64 record_id, u64 offset)
678 struct apei_exec_context ctx;
679 u64 timeout = FIRMWARE_TIMEOUT;
680 u64 val;
681 int rc;
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;
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;
716 return erst_errno(val);
719 static int __erst_clear_from_storage(u64 record_id)
721 struct apei_exec_context ctx;
722 u64 timeout = FIRMWARE_TIMEOUT;
723 u64 val;
724 int rc;
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;
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;
755 return erst_errno(val);
758 /* NVRAM ERST Error Log Address Range is not supported yet */
759 static void pr_unimpl_nvram(void)
761 if (printk_ratelimit())
762 pr_warning(ERST_PFX
763 "NVRAM ERST Log Address Range is not implemented yet\n");
766 static int __erst_write_to_nvram(const struct cper_record_header *record)
768 /* do not print message, because printk is not safe for NMI */
769 return -ENOSYS;
772 static int __erst_read_to_erange_from_nvram(u64 record_id, u64 *offset)
774 pr_unimpl_nvram();
775 return -ENOSYS;
778 static int __erst_clear_from_nvram(u64 record_id)
780 pr_unimpl_nvram();
781 return -ENOSYS;
784 int erst_write(const struct cper_record_header *record)
786 int rc;
787 unsigned long flags;
788 struct cper_record_header *rcd_erange;
790 if (erst_disable)
791 return -ENODEV;
793 if (memcmp(record->signature, CPER_SIG_RECORD, CPER_SIG_SIZE))
794 return -EINVAL;
796 if (erst_erange.attr & ERST_RANGE_NVRAM) {
797 if (!raw_spin_trylock_irqsave(&erst_lock, flags))
798 return -EBUSY;
799 rc = __erst_write_to_nvram(record);
800 raw_spin_unlock_irqrestore(&erst_lock, flags);
801 return rc;
804 if (record->record_length > erst_erange.size)
805 return -EINVAL;
807 if (!raw_spin_trylock_irqsave(&erst_lock, flags))
808 return -EBUSY;
809 memcpy(erst_erange.vaddr, record, record->record_length);
810 rcd_erange = erst_erange.vaddr;
811 /* signature for serialization system */
812 memcpy(&rcd_erange->persistence_information, "ER", 2);
814 rc = __erst_write_to_storage(0);
815 raw_spin_unlock_irqrestore(&erst_lock, flags);
817 return rc;
819 EXPORT_SYMBOL_GPL(erst_write);
821 static int __erst_read_to_erange(u64 record_id, u64 *offset)
823 int rc;
825 if (erst_erange.attr & ERST_RANGE_NVRAM)
826 return __erst_read_to_erange_from_nvram(
827 record_id, offset);
829 rc = __erst_read_from_storage(record_id, 0);
830 if (rc)
831 return rc;
832 *offset = 0;
834 return 0;
837 static ssize_t __erst_read(u64 record_id, struct cper_record_header *record,
838 size_t buflen)
840 int rc;
841 u64 offset, len = 0;
842 struct cper_record_header *rcd_tmp;
844 rc = __erst_read_to_erange(record_id, &offset);
845 if (rc)
846 return rc;
847 rcd_tmp = erst_erange.vaddr + offset;
848 len = rcd_tmp->record_length;
849 if (len <= buflen)
850 memcpy(record, rcd_tmp, len);
852 return len;
856 * If return value > buflen, the buffer size is not big enough,
857 * else if return value < 0, something goes wrong,
858 * else everything is OK, and return value is record length
860 ssize_t erst_read(u64 record_id, struct cper_record_header *record,
861 size_t buflen)
863 ssize_t len;
864 unsigned long flags;
866 if (erst_disable)
867 return -ENODEV;
869 raw_spin_lock_irqsave(&erst_lock, flags);
870 len = __erst_read(record_id, record, buflen);
871 raw_spin_unlock_irqrestore(&erst_lock, flags);
872 return len;
874 EXPORT_SYMBOL_GPL(erst_read);
876 int erst_clear(u64 record_id)
878 int rc, i;
879 unsigned long flags;
880 u64 *entries;
882 if (erst_disable)
883 return -ENODEV;
885 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);
886 if (rc)
887 return rc;
888 raw_spin_lock_irqsave(&erst_lock, flags);
889 if (erst_erange.attr & ERST_RANGE_NVRAM)
890 rc = __erst_clear_from_nvram(record_id);
891 else
892 rc = __erst_clear_from_storage(record_id);
893 raw_spin_unlock_irqrestore(&erst_lock, flags);
894 if (rc)
895 goto out;
896 entries = erst_record_id_cache.entries;
897 for (i = 0; i < erst_record_id_cache.len; i++) {
898 if (entries[i] == record_id)
899 entries[i] = APEI_ERST_INVALID_RECORD_ID;
901 __erst_record_id_cache_compact();
902 out:
903 mutex_unlock(&erst_record_id_cache.lock);
904 return rc;
906 EXPORT_SYMBOL_GPL(erst_clear);
908 static int __init setup_erst_disable(char *str)
910 erst_disable = 1;
911 return 0;
914 __setup("erst_disable", setup_erst_disable);
916 static int erst_check_table(struct acpi_table_erst *erst_tab)
918 if ((erst_tab->header_length !=
919 (sizeof(struct acpi_table_erst) - sizeof(erst_tab->header)))
920 && (erst_tab->header_length != sizeof(struct acpi_table_erst)))
921 return -EINVAL;
922 if (erst_tab->header.length < sizeof(struct acpi_table_erst))
923 return -EINVAL;
924 if (erst_tab->entries !=
925 (erst_tab->header.length - sizeof(struct acpi_table_erst)) /
926 sizeof(struct acpi_erst_entry))
927 return -EINVAL;
929 return 0;
932 static int erst_open_pstore(struct pstore_info *psi);
933 static int erst_close_pstore(struct pstore_info *psi);
934 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
935 struct timespec *time, char **buf,
936 struct pstore_info *psi);
937 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
938 u64 *id, unsigned int part, int count, size_t hsize,
939 size_t size, struct pstore_info *psi);
940 static int erst_clearer(enum pstore_type_id type, u64 id, int count,
941 struct timespec time, struct pstore_info *psi);
943 static struct pstore_info erst_info = {
944 .owner = THIS_MODULE,
945 .name = "erst",
946 .open = erst_open_pstore,
947 .close = erst_close_pstore,
948 .read = erst_reader,
949 .write = erst_writer,
950 .erase = erst_clearer
953 #define CPER_CREATOR_PSTORE \
954 UUID_LE(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c, \
955 0x64, 0x90, 0xb8, 0x9d)
956 #define CPER_SECTION_TYPE_DMESG \
957 UUID_LE(0xc197e04e, 0xd545, 0x4a70, 0x9c, 0x17, 0xa5, 0x54, \
958 0x94, 0x19, 0xeb, 0x12)
959 #define CPER_SECTION_TYPE_MCE \
960 UUID_LE(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96, \
961 0x04, 0x4a, 0x38, 0xfc)
963 struct cper_pstore_record {
964 struct cper_record_header hdr;
965 struct cper_section_descriptor sec_hdr;
966 char data[];
967 } __packed;
969 static int reader_pos;
971 static int erst_open_pstore(struct pstore_info *psi)
973 int rc;
975 if (erst_disable)
976 return -ENODEV;
978 rc = erst_get_record_id_begin(&reader_pos);
980 return rc;
983 static int erst_close_pstore(struct pstore_info *psi)
985 erst_get_record_id_end();
987 return 0;
990 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
991 struct timespec *time, char **buf,
992 struct pstore_info *psi)
994 int rc;
995 ssize_t len = 0;
996 u64 record_id;
997 struct cper_pstore_record *rcd;
998 size_t rcd_len = sizeof(*rcd) + erst_info.bufsize;
1000 if (erst_disable)
1001 return -ENODEV;
1003 rcd = kmalloc(rcd_len, GFP_KERNEL);
1004 if (!rcd) {
1005 rc = -ENOMEM;
1006 goto out;
1008 skip:
1009 rc = erst_get_record_id_next(&reader_pos, &record_id);
1010 if (rc)
1011 goto out;
1013 /* no more record */
1014 if (record_id == APEI_ERST_INVALID_RECORD_ID) {
1015 rc = -EINVAL;
1016 goto out;
1019 len = erst_read(record_id, &rcd->hdr, rcd_len);
1020 /* The record may be cleared by others, try read next record */
1021 if (len == -ENOENT)
1022 goto skip;
1023 else if (len < sizeof(*rcd)) {
1024 rc = -EIO;
1025 goto out;
1027 if (uuid_le_cmp(rcd->hdr.creator_id, CPER_CREATOR_PSTORE) != 0)
1028 goto skip;
1030 *buf = kmalloc(len, GFP_KERNEL);
1031 if (*buf == NULL) {
1032 rc = -ENOMEM;
1033 goto out;
1035 memcpy(*buf, rcd->data, len - sizeof(*rcd));
1036 *id = record_id;
1037 if (uuid_le_cmp(rcd->sec_hdr.section_type,
1038 CPER_SECTION_TYPE_DMESG) == 0)
1039 *type = PSTORE_TYPE_DMESG;
1040 else if (uuid_le_cmp(rcd->sec_hdr.section_type,
1041 CPER_SECTION_TYPE_MCE) == 0)
1042 *type = PSTORE_TYPE_MCE;
1043 else
1044 *type = PSTORE_TYPE_UNKNOWN;
1046 if (rcd->hdr.validation_bits & CPER_VALID_TIMESTAMP)
1047 time->tv_sec = rcd->hdr.timestamp;
1048 else
1049 time->tv_sec = 0;
1050 time->tv_nsec = 0;
1052 out:
1053 kfree(rcd);
1054 return (rc < 0) ? rc : (len - sizeof(*rcd));
1057 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
1058 u64 *id, unsigned int part, int count, size_t hsize,
1059 size_t size, struct pstore_info *psi)
1061 struct cper_pstore_record *rcd = (struct cper_pstore_record *)
1062 (erst_info.buf - sizeof(*rcd));
1063 int ret;
1065 memset(rcd, 0, sizeof(*rcd));
1066 memcpy(rcd->hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE);
1067 rcd->hdr.revision = CPER_RECORD_REV;
1068 rcd->hdr.signature_end = CPER_SIG_END;
1069 rcd->hdr.section_count = 1;
1070 rcd->hdr.error_severity = CPER_SEV_FATAL;
1071 /* timestamp valid. platform_id, partition_id are invalid */
1072 rcd->hdr.validation_bits = CPER_VALID_TIMESTAMP;
1073 rcd->hdr.timestamp = get_seconds();
1074 rcd->hdr.record_length = sizeof(*rcd) + size;
1075 rcd->hdr.creator_id = CPER_CREATOR_PSTORE;
1076 rcd->hdr.notification_type = CPER_NOTIFY_MCE;
1077 rcd->hdr.record_id = cper_next_record_id();
1078 rcd->hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR;
1080 rcd->sec_hdr.section_offset = sizeof(*rcd);
1081 rcd->sec_hdr.section_length = size;
1082 rcd->sec_hdr.revision = CPER_SEC_REV;
1083 /* fru_id and fru_text is invalid */
1084 rcd->sec_hdr.validation_bits = 0;
1085 rcd->sec_hdr.flags = CPER_SEC_PRIMARY;
1086 switch (type) {
1087 case PSTORE_TYPE_DMESG:
1088 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG;
1089 break;
1090 case PSTORE_TYPE_MCE:
1091 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_MCE;
1092 break;
1093 default:
1094 return -EINVAL;
1096 rcd->sec_hdr.section_severity = CPER_SEV_FATAL;
1098 ret = erst_write(&rcd->hdr);
1099 *id = rcd->hdr.record_id;
1101 return ret;
1104 static int erst_clearer(enum pstore_type_id type, u64 id, int count,
1105 struct timespec time, struct pstore_info *psi)
1107 return erst_clear(id);
1110 static int __init erst_init(void)
1112 int rc = 0;
1113 acpi_status status;
1114 struct apei_exec_context ctx;
1115 struct apei_resources erst_resources;
1116 struct resource *r;
1117 char *buf;
1119 if (acpi_disabled)
1120 goto err;
1122 if (erst_disable) {
1123 pr_info(ERST_PFX
1124 "Error Record Serialization Table (ERST) support is disabled.\n");
1125 goto err;
1128 status = acpi_get_table(ACPI_SIG_ERST, 0,
1129 (struct acpi_table_header **)&erst_tab);
1130 if (status == AE_NOT_FOUND)
1131 goto err;
1132 else if (ACPI_FAILURE(status)) {
1133 const char *msg = acpi_format_exception(status);
1134 pr_err(ERST_PFX "Failed to get table, %s\n", msg);
1135 rc = -EINVAL;
1136 goto err;
1139 rc = erst_check_table(erst_tab);
1140 if (rc) {
1141 pr_err(FW_BUG ERST_PFX "ERST table is invalid\n");
1142 goto err;
1145 apei_resources_init(&erst_resources);
1146 erst_exec_ctx_init(&ctx);
1147 rc = apei_exec_collect_resources(&ctx, &erst_resources);
1148 if (rc)
1149 goto err_fini;
1150 rc = apei_resources_request(&erst_resources, "APEI ERST");
1151 if (rc)
1152 goto err_fini;
1153 rc = apei_exec_pre_map_gars(&ctx);
1154 if (rc)
1155 goto err_release;
1156 rc = erst_get_erange(&erst_erange);
1157 if (rc) {
1158 if (rc == -ENODEV)
1159 pr_info(ERST_PFX
1160 "The corresponding hardware device or firmware implementation "
1161 "is not available.\n");
1162 else
1163 pr_err(ERST_PFX
1164 "Failed to get Error Log Address Range.\n");
1165 goto err_unmap_reg;
1168 r = request_mem_region(erst_erange.base, erst_erange.size, "APEI ERST");
1169 if (!r) {
1170 pr_err(ERST_PFX
1171 "Can not request iomem region <0x%16llx-0x%16llx> for ERST.\n",
1172 (unsigned long long)erst_erange.base,
1173 (unsigned long long)erst_erange.base + erst_erange.size);
1174 rc = -EIO;
1175 goto err_unmap_reg;
1177 rc = -ENOMEM;
1178 erst_erange.vaddr = ioremap_cache(erst_erange.base,
1179 erst_erange.size);
1180 if (!erst_erange.vaddr)
1181 goto err_release_erange;
1183 pr_info(ERST_PFX
1184 "Error Record Serialization Table (ERST) support is initialized.\n");
1186 buf = kmalloc(erst_erange.size, GFP_KERNEL);
1187 spin_lock_init(&erst_info.buf_lock);
1188 if (buf) {
1189 erst_info.buf = buf + sizeof(struct cper_pstore_record);
1190 erst_info.bufsize = erst_erange.size -
1191 sizeof(struct cper_pstore_record);
1192 rc = pstore_register(&erst_info);
1193 if (rc) {
1194 if (rc != -EPERM)
1195 pr_info(ERST_PFX
1196 "Could not register with persistent store\n");
1197 erst_info.buf = NULL;
1198 erst_info.bufsize = 0;
1199 kfree(buf);
1201 } else
1202 pr_err(ERST_PFX
1203 "Failed to allocate %lld bytes for persistent store error log\n",
1204 erst_erange.size);
1206 return 0;
1208 err_release_erange:
1209 release_mem_region(erst_erange.base, erst_erange.size);
1210 err_unmap_reg:
1211 apei_exec_post_unmap_gars(&ctx);
1212 err_release:
1213 apei_resources_release(&erst_resources);
1214 err_fini:
1215 apei_resources_fini(&erst_resources);
1216 err:
1217 erst_disable = 1;
1218 return rc;
1221 device_initcall(erst_init);