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