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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / drivers / acpi / apei / erst.c
blob2ca59dc69f7f6b034660bfdc04462230880456f9
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
61 int erst_disable;
62 EXPORT_SYMBOL_GPL(erst_disable);
63
64 static 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 */
75 static 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 */
90 static DEFINE_RAW_SPINLOCK(erst_lock);
91
92 static 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
109 static 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
122 static int erst_exec_load_var1(struct apei_exec_context *ctx,
123 struct acpi_whea_header *entry)
124 {
125 return __apei_exec_read_register(entry, &ctx->var1);
126 }
127
128 static int erst_exec_load_var2(struct apei_exec_context *ctx,
129 struct acpi_whea_header *entry)
130 {
131 return __apei_exec_read_register(entry, &ctx->var2);
132 }
133
134 static int erst_exec_store_var1(struct apei_exec_context *ctx,
135 struct acpi_whea_header *entry)
136 {
137 return __apei_exec_write_register(entry, ctx->var1);
138 }
139
140 static int erst_exec_add(struct apei_exec_context *ctx,
141 struct acpi_whea_header *entry)
142 {
143 ctx->var1 += ctx->var2;
144 return 0;
145 }
146
147 static int erst_exec_subtract(struct apei_exec_context *ctx,
148 struct acpi_whea_header *entry)
149 {
150 ctx->var1 -= ctx->var2;
151 return 0;
152 }
153
154 static int erst_exec_add_value(struct apei_exec_context *ctx,
155 struct acpi_whea_header *entry)
156 {
157 int rc;
158 u64 val;
159
160 rc = __apei_exec_read_register(entry, &val);
161 if (rc)
162 return rc;
163 val += ctx->value;
164 rc = __apei_exec_write_register(entry, val);
165 return rc;
166 }
167
168 static int erst_exec_subtract_value(struct apei_exec_context *ctx,
169 struct acpi_whea_header *entry)
170 {
171 int rc;
172 u64 val;
173
174 rc = __apei_exec_read_register(entry, &val);
175 if (rc)
176 return rc;
177 val -= ctx->value;
178 rc = __apei_exec_write_register(entry, val);
179 return rc;
180 }
181
182 static int erst_exec_stall(struct apei_exec_context *ctx,
183 struct acpi_whea_header *entry)
184 {
185 u64 stall_time;
186
187 if (ctx->value > FIRMWARE_MAX_STALL) {
188 if (!in_nmi())
189 pr_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
199 static int erst_exec_stall_while_true(struct apei_exec_context *ctx,
200 struct acpi_whea_header *entry)
201 {
202 int rc;
203 u64 val;
204 u64 timeout = FIRMWARE_TIMEOUT;
205 u64 stall_time;
206
207 if (ctx->var1 > FIRMWARE_MAX_STALL) {
208 if (!in_nmi())
209 pr_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
228 static int erst_exec_skip_next_instruction_if_true(
229 struct apei_exec_context *ctx,
230 struct acpi_whea_header *entry)
231 {
232 int rc;
233 u64 val;
234
235 rc = __apei_exec_read_register(entry, &val);
236 if (rc)
237 return rc;
238 if (val == ctx->value) {
239 ctx->ip += 2;
240 return APEI_EXEC_SET_IP;
241 }
242
243 return 0;
244 }
245
246 static int erst_exec_goto(struct apei_exec_context *ctx,
247 struct acpi_whea_header *entry)
248 {
249 ctx->ip = ctx->value;
250 return APEI_EXEC_SET_IP;
251 }
252
253 static int erst_exec_set_src_address_base(struct apei_exec_context *ctx,
254 struct acpi_whea_header *entry)
255 {
256 return __apei_exec_read_register(entry, &ctx->src_base);
257 }
258
259 static int erst_exec_set_dst_address_base(struct apei_exec_context *ctx,
260 struct acpi_whea_header *entry)
261 {
262 return __apei_exec_read_register(entry, &ctx->dst_base);
263 }
264
265 static int erst_exec_move_data(struct apei_exec_context *ctx,
266 struct acpi_whea_header *entry)
267 {
268 int rc;
269 u64 offset;
270 void *src, *dst;
271
272 /* ioremap does not work in interrupt context */
273 if (in_interrupt()) {
274 pr_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
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,
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
377 static 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
383 static 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
405 static 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
417 ssize_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 }
431 EXPORT_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
436 struct erst_record_id_cache {
437 struct mutex lock;
438 u64 *entries;
439 int len;
440 int size;
441 int refcount;
442 };
443
444 static struct erst_record_id_cache erst_record_id_cache = {
445 .lock = __MUTEX_INITIALIZER(erst_record_id_cache.lock),
446 .refcount = 0,
447 };
448
449 static 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
463 int 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 }
480 EXPORT_SYMBOL_GPL(erst_get_record_id_begin);
481
482 /* erst_record_id_cache.lock must be held by caller */
483 static 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;
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;
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 */
556 int erst_get_record_id_next(int *pos, u64 *record_id)
557 {
558 int rc = 0;
559 u64 *entries;
560
561 if (erst_disable)
562 return -ENODEV;
563
564 /* must be enclosed by erst_get_record_id_begin/end */
565 BUG_ON(!erst_record_id_cache.refcount);
566 BUG_ON(*pos < 0 || *pos > erst_record_id_cache.len);
567
568 mutex_lock(&erst_record_id_cache.lock);
569 entries = erst_record_id_cache.entries;
570 for (; *pos < erst_record_id_cache.len; (*pos)++)
571 if (entries[*pos] != APEI_ERST_INVALID_RECORD_ID)
572 break;
573 /* found next record id in cache */
574 if (*pos < erst_record_id_cache.len) {
575 *record_id = entries[*pos];
576 (*pos)++;
577 goto out_unlock;
578 }
579
580 /* Try to add one more record ID to cache */
581 rc = __erst_record_id_cache_add_one();
582 if (rc < 0)
583 goto out_unlock;
584 /* successfully add one new ID */
585 if (rc == 1) {
586 *record_id = erst_record_id_cache.entries[*pos];
587 (*pos)++;
588 rc = 0;
589 } else {
590 *pos = -1;
591 *record_id = APEI_ERST_INVALID_RECORD_ID;
592 }
593 out_unlock:
594 mutex_unlock(&erst_record_id_cache.lock);
595
596 return rc;
597 }
598 EXPORT_SYMBOL_GPL(erst_get_record_id_next);
599
600 /* erst_record_id_cache.lock must be held by caller */
601 static void __erst_record_id_cache_compact(void)
602 {
603 int i, wpos = 0;
604 u64 *entries;
605
606 if (erst_record_id_cache.refcount)
607 return;
608
609 entries = erst_record_id_cache.entries;
610 for (i = 0; i < erst_record_id_cache.len; i++) {
611 if (entries[i] == APEI_ERST_INVALID_RECORD_ID)
612 continue;
613 if (wpos != i)
614 memcpy(&entries[wpos], &entries[i], sizeof(entries[i]));
615 wpos++;
616 }
617 erst_record_id_cache.len = wpos;
618 }
619
620 void erst_get_record_id_end(void)
621 {
622 /*
623 * erst_disable != 0 should be detected by invoker via the
624 * return value of erst_get_record_id_begin/next, so this
625 * function should not be called for erst_disable != 0.
626 */
627 BUG_ON(erst_disable);
628
629 mutex_lock(&erst_record_id_cache.lock);
630 erst_record_id_cache.refcount--;
631 BUG_ON(erst_record_id_cache.refcount < 0);
632 __erst_record_id_cache_compact();
633 mutex_unlock(&erst_record_id_cache.lock);
634 }
635 EXPORT_SYMBOL_GPL(erst_get_record_id_end);
636
637 static int __erst_write_to_storage(u64 offset)
638 {
639 struct apei_exec_context ctx;
640 u64 timeout = FIRMWARE_TIMEOUT;
641 u64 val;
642 int rc;
643
644 erst_exec_ctx_init(&ctx);
645 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_WRITE);
646 if (rc)
647 return rc;
648 apei_exec_ctx_set_input(&ctx, offset);
649 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);
650 if (rc)
651 return rc;
652 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
653 if (rc)
654 return rc;
655 for (;;) {
656 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
657 if (rc)
658 return rc;
659 val = apei_exec_ctx_get_output(&ctx);
660 if (!val)
661 break;
662 if (erst_timedout(&timeout, SPIN_UNIT))
663 return -EIO;
664 }
665 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
666 if (rc)
667 return rc;
668 val = apei_exec_ctx_get_output(&ctx);
669 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
670 if (rc)
671 return rc;
672
673 return erst_errno(val);
674 }
675
676 static int __erst_read_from_storage(u64 record_id, u64 offset)
677 {
678 struct apei_exec_context ctx;
679 u64 timeout = FIRMWARE_TIMEOUT;
680 u64 val;
681 int rc;
682
683 erst_exec_ctx_init(&ctx);
684 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_READ);
685 if (rc)
686 return rc;
687 apei_exec_ctx_set_input(&ctx, offset);
688 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);
689 if (rc)
690 return rc;
691 apei_exec_ctx_set_input(&ctx, record_id);
692 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);
693 if (rc)
694 return rc;
695 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
696 if (rc)
697 return rc;
698 for (;;) {
699 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
700 if (rc)
701 return rc;
702 val = apei_exec_ctx_get_output(&ctx);
703 if (!val)
704 break;
705 if (erst_timedout(&timeout, SPIN_UNIT))
706 return -EIO;
707 };
708 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
709 if (rc)
710 return rc;
711 val = apei_exec_ctx_get_output(&ctx);
712 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
713 if (rc)
714 return rc;
715
716 return erst_errno(val);
717 }
718
719 static int __erst_clear_from_storage(u64 record_id)
720 {
721 struct apei_exec_context ctx;
722 u64 timeout = FIRMWARE_TIMEOUT;
723 u64 val;
724 int rc;
725
726 erst_exec_ctx_init(&ctx);
727 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_CLEAR);
728 if (rc)
729 return rc;
730 apei_exec_ctx_set_input(&ctx, record_id);
731 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);
732 if (rc)
733 return rc;
734 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
735 if (rc)
736 return rc;
737 for (;;) {
738 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
739 if (rc)
740 return rc;
741 val = apei_exec_ctx_get_output(&ctx);
742 if (!val)
743 break;
744 if (erst_timedout(&timeout, SPIN_UNIT))
745 return -EIO;
746 }
747 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
748 if (rc)
749 return rc;
750 val = apei_exec_ctx_get_output(&ctx);
751 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
752 if (rc)
753 return rc;
754
755 return erst_errno(val);
756 }
757
758 /* NVRAM ERST Error Log Address Range is not supported yet */
759 static void pr_unimpl_nvram(void)
760 {
761 if (printk_ratelimit())
762 pr_warning(ERST_PFX
763 "NVRAM ERST Log Address Range is not implemented yet\n");
764 }
765
766 static 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
772 static int __erst_read_to_erange_from_nvram(u64 record_id, u64 *offset)
773 {
774 pr_unimpl_nvram();
775 return -ENOSYS;
776 }
777
778 static int __erst_clear_from_nvram(u64 record_id)
779 {
780 pr_unimpl_nvram();
781 return -ENOSYS;
782 }
783
784 int 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 }
819 EXPORT_SYMBOL_GPL(erst_write);
820
821 static 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
837 static 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 */
860 ssize_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 }
874 EXPORT_SYMBOL_GPL(erst_read);
875
876 int 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();
902 out:
903 mutex_unlock(&erst_record_id_cache.lock);
904 return rc;
905 }
906 EXPORT_SYMBOL_GPL(erst_clear);
907
908 static 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
916 static 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
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,
935 struct timespec *time, struct pstore_info *psi);
936 static u64 erst_writer(enum pstore_type_id type, unsigned int part,
937 size_t size, struct pstore_info *psi);
938 static int erst_clearer(enum pstore_type_id type, u64 id,
939 struct pstore_info *psi);
940
941 static 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
961 struct cper_pstore_record {
962 struct cper_record_header hdr;
963 struct cper_section_descriptor sec_hdr;
964 char data[];
965 } __packed;
966
967 static int reader_pos;
968
969 static 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
981 static int erst_close_pstore(struct pstore_info *psi)
982 {
983 erst_get_record_id_end();
984
985 return 0;
986 }
987
988 static 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
1000 skip:
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
1039 out:
1040 return (rc < 0) ? rc : (len - sizeof(*rcd));
1041 }
1042
1043 static 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
1087 static int erst_clearer(enum pstore_type_id type, u64 id,
1088 struct pstore_info *psi)
1089 {
1090 return erst_clear(id);
1091 }
1092
1093 static 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
1184 err_release_erange:
1185 release_mem_region(erst_erange.base, erst_erange.size);
1186 err_unmap_reg:
1187 apei_exec_post_unmap_gars(&ctx);
1188 err_release:
1189 apei_resources_release(&erst_resources);
1190 err_fini:
1191 apei_resources_fini(&erst_resources);
1192 err:
1193 erst_disable = 1;
1194 return rc;
1195 }
1196
1197 device_initcall(erst_init);
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