1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * APEI Error Record Serialization Table support
4 *
5 * ERST is a way provided by APEI to save and retrieve hardware error
6 * information to and from a persistent store.
7 *
8 * For more information about ERST, please refer to ACPI Specification
9 * version 4.0, section 17.4.
10 *
11 * Copyright 2010 Intel Corp.
12 * Author: Huang Ying <ying.huang@intel.com>
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/delay.h>
19 #include <linux/io.h>
20 #include <linux/acpi.h>
21 #include <linux/uaccess.h>
22 #include <linux/cper.h>
23 #include <linux/nmi.h>
24 #include <linux/hardirq.h>
25 #include <linux/pstore.h>
26 #include <linux/vmalloc.h>
27 #include <linux/mm.h> /* kvfree() */
28 #include <acpi/apei.h>
29
30 #include "apei-internal.h"
31
32 #undef pr_fmt
33 #define pr_fmt(fmt) "ERST: " fmt
34
35 /* ERST command status */
36 #define ERST_STATUS_SUCCESS 0x0
37 #define ERST_STATUS_NOT_ENOUGH_SPACE 0x1
38 #define ERST_STATUS_HARDWARE_NOT_AVAILABLE 0x2
39 #define ERST_STATUS_FAILED 0x3
40 #define ERST_STATUS_RECORD_STORE_EMPTY 0x4
41 #define ERST_STATUS_RECORD_NOT_FOUND 0x5
42
43 #define ERST_TAB_ENTRY(tab) \
44 ((struct acpi_whea_header *)((char *)(tab) + \
45 sizeof(struct acpi_table_erst)))
46
47 #define SPIN_UNIT 100 /* 100ns */
48 /* Firmware should respond within 1 milliseconds */
49 #define FIRMWARE_TIMEOUT (1 * NSEC_PER_MSEC)
50 #define FIRMWARE_MAX_STALL 50 /* 50us */
51
52 int erst_disable;
53 EXPORT_SYMBOL_GPL(erst_disable);
54
55 static struct acpi_table_erst *erst_tab;
56
57 /* ERST Error Log Address Range attributes */
58 #define ERST_RANGE_RESERVED 0x0001
59 #define ERST_RANGE_NVRAM 0x0002
60 #define ERST_RANGE_SLOW 0x0004
61
62 /*
63 * ERST Error Log Address Range, used as buffer for reading/writing
64 * error records.
65 */
66 static struct erst_erange {
67 u64 base;
68 u64 size;
69 void __iomem *vaddr;
70 u32 attr;
71 } erst_erange;
72
73 /*
74 * Prevent ERST interpreter to run simultaneously, because the
75 * corresponding firmware implementation may not work properly when
76 * invoked simultaneously.
77 *
78 * It is used to provide exclusive accessing for ERST Error Log
79 * Address Range too.
80 */
81 static DEFINE_RAW_SPINLOCK(erst_lock);
82
erst_errno(int command_status)83 static inline int erst_errno(int command_status)
84 {
85 switch (command_status) {
86 case ERST_STATUS_SUCCESS:
87 return 0;
88 case ERST_STATUS_HARDWARE_NOT_AVAILABLE:
89 return -ENODEV;
90 case ERST_STATUS_NOT_ENOUGH_SPACE:
91 return -ENOSPC;
92 case ERST_STATUS_RECORD_STORE_EMPTY:
93 case ERST_STATUS_RECORD_NOT_FOUND:
94 return -ENOENT;
95 default:
96 return -EINVAL;
97 }
98 }
99
erst_timedout(u64 * t,u64 spin_unit)100 static int erst_timedout(u64 *t, u64 spin_unit)
101 {
102 if ((s64)*t < spin_unit) {
103 pr_warn(FW_WARN "Firmware does not respond in time.\n");
104 return 1;
105 }
106 *t -= spin_unit;
107 ndelay(spin_unit);
108 touch_nmi_watchdog();
109 return 0;
110 }
111
erst_exec_load_var1(struct apei_exec_context * ctx,struct acpi_whea_header * entry)112 static int erst_exec_load_var1(struct apei_exec_context *ctx,
113 struct acpi_whea_header *entry)
114 {
115 return __apei_exec_read_register(entry, &ctx->var1);
116 }
117
erst_exec_load_var2(struct apei_exec_context * ctx,struct acpi_whea_header * entry)118 static int erst_exec_load_var2(struct apei_exec_context *ctx,
119 struct acpi_whea_header *entry)
120 {
121 return __apei_exec_read_register(entry, &ctx->var2);
122 }
123
erst_exec_store_var1(struct apei_exec_context * ctx,struct acpi_whea_header * entry)124 static int erst_exec_store_var1(struct apei_exec_context *ctx,
125 struct acpi_whea_header *entry)
126 {
127 return __apei_exec_write_register(entry, ctx->var1);
128 }
129
erst_exec_add(struct apei_exec_context * ctx,struct acpi_whea_header * entry)130 static int erst_exec_add(struct apei_exec_context *ctx,
131 struct acpi_whea_header *entry)
132 {
133 ctx->var1 += ctx->var2;
134 return 0;
135 }
136
erst_exec_subtract(struct apei_exec_context * ctx,struct acpi_whea_header * entry)137 static int erst_exec_subtract(struct apei_exec_context *ctx,
138 struct acpi_whea_header *entry)
139 {
140 ctx->var1 -= ctx->var2;
141 return 0;
142 }
143
erst_exec_add_value(struct apei_exec_context * ctx,struct acpi_whea_header * entry)144 static int erst_exec_add_value(struct apei_exec_context *ctx,
145 struct acpi_whea_header *entry)
146 {
147 int rc;
148 u64 val;
149
150 rc = __apei_exec_read_register(entry, &val);
151 if (rc)
152 return rc;
153 val += ctx->value;
154 rc = __apei_exec_write_register(entry, val);
155 return rc;
156 }
157
erst_exec_subtract_value(struct apei_exec_context * ctx,struct acpi_whea_header * entry)158 static int erst_exec_subtract_value(struct apei_exec_context *ctx,
159 struct acpi_whea_header *entry)
160 {
161 int rc;
162 u64 val;
163
164 rc = __apei_exec_read_register(entry, &val);
165 if (rc)
166 return rc;
167 val -= ctx->value;
168 rc = __apei_exec_write_register(entry, val);
169 return rc;
170 }
171
erst_exec_stall(struct apei_exec_context * ctx,struct acpi_whea_header * entry)172 static int erst_exec_stall(struct apei_exec_context *ctx,
173 struct acpi_whea_header *entry)
174 {
175 u64 stall_time;
176
177 if (ctx->value > FIRMWARE_MAX_STALL) {
178 if (!in_nmi())
179 pr_warn(FW_WARN
180 "Too long stall time for stall instruction: 0x%llx.\n",
181 ctx->value);
182 stall_time = FIRMWARE_MAX_STALL;
183 } else
184 stall_time = ctx->value;
185 udelay(stall_time);
186 return 0;
187 }
188
erst_exec_stall_while_true(struct apei_exec_context * ctx,struct acpi_whea_header * entry)189 static int erst_exec_stall_while_true(struct apei_exec_context *ctx,
190 struct acpi_whea_header *entry)
191 {
192 int rc;
193 u64 val;
194 u64 timeout = FIRMWARE_TIMEOUT;
195 u64 stall_time;
196
197 if (ctx->var1 > FIRMWARE_MAX_STALL) {
198 if (!in_nmi())
199 pr_warn(FW_WARN
200 "Too long stall time for stall while true instruction: 0x%llx.\n",
201 ctx->var1);
202 stall_time = FIRMWARE_MAX_STALL;
203 } else
204 stall_time = ctx->var1;
205
206 for (;;) {
207 rc = __apei_exec_read_register(entry, &val);
208 if (rc)
209 return rc;
210 if (val != ctx->value)
211 break;
212 if (erst_timedout(&timeout, stall_time * NSEC_PER_USEC))
213 return -EIO;
214 }
215 return 0;
216 }
217
erst_exec_skip_next_instruction_if_true(struct apei_exec_context * ctx,struct acpi_whea_header * entry)218 static int erst_exec_skip_next_instruction_if_true(
219 struct apei_exec_context *ctx,
220 struct acpi_whea_header *entry)
221 {
222 int rc;
223 u64 val;
224
225 rc = __apei_exec_read_register(entry, &val);
226 if (rc)
227 return rc;
228 if (val == ctx->value) {
229 ctx->ip += 2;
230 return APEI_EXEC_SET_IP;
231 }
232
233 return 0;
234 }
235
erst_exec_goto(struct apei_exec_context * ctx,struct acpi_whea_header * entry)236 static int erst_exec_goto(struct apei_exec_context *ctx,
237 struct acpi_whea_header *entry)
238 {
239 ctx->ip = ctx->value;
240 return APEI_EXEC_SET_IP;
241 }
242
erst_exec_set_src_address_base(struct apei_exec_context * ctx,struct acpi_whea_header * entry)243 static int erst_exec_set_src_address_base(struct apei_exec_context *ctx,
244 struct acpi_whea_header *entry)
245 {
246 return __apei_exec_read_register(entry, &ctx->src_base);
247 }
248
erst_exec_set_dst_address_base(struct apei_exec_context * ctx,struct acpi_whea_header * entry)249 static int erst_exec_set_dst_address_base(struct apei_exec_context *ctx,
250 struct acpi_whea_header *entry)
251 {
252 return __apei_exec_read_register(entry, &ctx->dst_base);
253 }
254
erst_exec_move_data(struct apei_exec_context * ctx,struct acpi_whea_header * entry)255 static int erst_exec_move_data(struct apei_exec_context *ctx,
256 struct acpi_whea_header *entry)
257 {
258 int rc;
259 u64 offset;
260 void *src, *dst;
261
262 /* ioremap does not work in interrupt context */
263 if (in_interrupt()) {
264 pr_warn("MOVE_DATA can not be used in interrupt context.\n");
265 return -EBUSY;
266 }
267
268 rc = __apei_exec_read_register(entry, &offset);
269 if (rc)
270 return rc;
271
272 src = ioremap(ctx->src_base + offset, ctx->var2);
273 if (!src)
274 return -ENOMEM;
275 dst = ioremap(ctx->dst_base + offset, ctx->var2);
276 if (!dst) {
277 iounmap(src);
278 return -ENOMEM;
279 }
280
281 memmove(dst, src, ctx->var2);
282
283 iounmap(src);
284 iounmap(dst);
285
286 return 0;
287 }
288
289 static struct apei_exec_ins_type erst_ins_type[] = {
290 [ACPI_ERST_READ_REGISTER] = {
291 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
292 .run = apei_exec_read_register,
293 },
294 [ACPI_ERST_READ_REGISTER_VALUE] = {
295 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
296 .run = apei_exec_read_register_value,
297 },
298 [ACPI_ERST_WRITE_REGISTER] = {
299 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
300 .run = apei_exec_write_register,
301 },
302 [ACPI_ERST_WRITE_REGISTER_VALUE] = {
303 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
304 .run = apei_exec_write_register_value,
305 },
306 [ACPI_ERST_NOOP] = {
307 .flags = 0,
308 .run = apei_exec_noop,
309 },
310 [ACPI_ERST_LOAD_VAR1] = {
311 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
312 .run = erst_exec_load_var1,
313 },
314 [ACPI_ERST_LOAD_VAR2] = {
315 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
316 .run = erst_exec_load_var2,
317 },
318 [ACPI_ERST_STORE_VAR1] = {
319 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
320 .run = erst_exec_store_var1,
321 },
322 [ACPI_ERST_ADD] = {
323 .flags = 0,
324 .run = erst_exec_add,
325 },
326 [ACPI_ERST_SUBTRACT] = {
327 .flags = 0,
328 .run = erst_exec_subtract,
329 },
330 [ACPI_ERST_ADD_VALUE] = {
331 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
332 .run = erst_exec_add_value,
333 },
334 [ACPI_ERST_SUBTRACT_VALUE] = {
335 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
336 .run = erst_exec_subtract_value,
337 },
338 [ACPI_ERST_STALL] = {
339 .flags = 0,
340 .run = erst_exec_stall,
341 },
342 [ACPI_ERST_STALL_WHILE_TRUE] = {
343 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
344 .run = erst_exec_stall_while_true,
345 },
346 [ACPI_ERST_SKIP_NEXT_IF_TRUE] = {
347 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
348 .run = erst_exec_skip_next_instruction_if_true,
349 },
350 [ACPI_ERST_GOTO] = {
351 .flags = 0,
352 .run = erst_exec_goto,
353 },
354 [ACPI_ERST_SET_SRC_ADDRESS_BASE] = {
355 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
356 .run = erst_exec_set_src_address_base,
357 },
358 [ACPI_ERST_SET_DST_ADDRESS_BASE] = {
359 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
360 .run = erst_exec_set_dst_address_base,
361 },
362 [ACPI_ERST_MOVE_DATA] = {
363 .flags = APEI_EXEC_INS_ACCESS_REGISTER,
364 .run = erst_exec_move_data,
365 },
366 };
367
erst_exec_ctx_init(struct apei_exec_context * ctx)368 static inline void erst_exec_ctx_init(struct apei_exec_context *ctx)
369 {
370 apei_exec_ctx_init(ctx, erst_ins_type, ARRAY_SIZE(erst_ins_type),
371 ERST_TAB_ENTRY(erst_tab), erst_tab->entries);
372 }
373
erst_get_erange(struct erst_erange * range)374 static int erst_get_erange(struct erst_erange *range)
375 {
376 struct apei_exec_context ctx;
377 int rc;
378
379 erst_exec_ctx_init(&ctx);
380 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_RANGE);
381 if (rc)
382 return rc;
383 range->base = apei_exec_ctx_get_output(&ctx);
384 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_LENGTH);
385 if (rc)
386 return rc;
387 range->size = apei_exec_ctx_get_output(&ctx);
388 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_ATTRIBUTES);
389 if (rc)
390 return rc;
391 range->attr = apei_exec_ctx_get_output(&ctx);
392
393 return 0;
394 }
395
__erst_get_record_count(void)396 static ssize_t __erst_get_record_count(void)
397 {
398 struct apei_exec_context ctx;
399 int rc;
400
401 erst_exec_ctx_init(&ctx);
402 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_COUNT);
403 if (rc)
404 return rc;
405 return apei_exec_ctx_get_output(&ctx);
406 }
407
erst_get_record_count(void)408 ssize_t erst_get_record_count(void)
409 {
410 ssize_t count;
411 unsigned long flags;
412
413 if (erst_disable)
414 return -ENODEV;
415
416 raw_spin_lock_irqsave(&erst_lock, flags);
417 count = __erst_get_record_count();
418 raw_spin_unlock_irqrestore(&erst_lock, flags);
419
420 return count;
421 }
422 EXPORT_SYMBOL_GPL(erst_get_record_count);
423
424 #define ERST_RECORD_ID_CACHE_SIZE_MIN 16
425 #define ERST_RECORD_ID_CACHE_SIZE_MAX 1024
426
427 struct erst_record_id_cache {
428 struct mutex lock;
429 u64 *entries;
430 int len;
431 int size;
432 int refcount;
433 };
434
435 static struct erst_record_id_cache erst_record_id_cache = {
436 .lock = __MUTEX_INITIALIZER(erst_record_id_cache.lock),
437 .refcount = 0,
438 };
439
__erst_get_next_record_id(u64 * record_id)440 static int __erst_get_next_record_id(u64 *record_id)
441 {
442 struct apei_exec_context ctx;
443 int rc;
444
445 erst_exec_ctx_init(&ctx);
446 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_ID);
447 if (rc)
448 return rc;
449 *record_id = apei_exec_ctx_get_output(&ctx);
450
451 return 0;
452 }
453
erst_get_record_id_begin(int * pos)454 int erst_get_record_id_begin(int *pos)
455 {
456 int rc;
457
458 if (erst_disable)
459 return -ENODEV;
460
461 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);
462 if (rc)
463 return rc;
464 erst_record_id_cache.refcount++;
465 mutex_unlock(&erst_record_id_cache.lock);
466
467 *pos = 0;
468
469 return 0;
470 }
471 EXPORT_SYMBOL_GPL(erst_get_record_id_begin);
472
473 /* erst_record_id_cache.lock must be held by caller */
__erst_record_id_cache_add_one(void)474 static int __erst_record_id_cache_add_one(void)
475 {
476 u64 id, prev_id, first_id;
477 int i, rc;
478 u64 *entries;
479 unsigned long flags;
480
481 id = prev_id = first_id = APEI_ERST_INVALID_RECORD_ID;
482 retry:
483 raw_spin_lock_irqsave(&erst_lock, flags);
484 rc = __erst_get_next_record_id(&id);
485 raw_spin_unlock_irqrestore(&erst_lock, flags);
486 if (rc == -ENOENT)
487 return 0;
488 if (rc)
489 return rc;
490 if (id == APEI_ERST_INVALID_RECORD_ID)
491 return 0;
492 /* can not skip current ID, or loop back to first ID */
493 if (id == prev_id || id == first_id)
494 return 0;
495 if (first_id == APEI_ERST_INVALID_RECORD_ID)
496 first_id = id;
497 prev_id = id;
498
499 entries = erst_record_id_cache.entries;
500 for (i = 0; i < erst_record_id_cache.len; i++) {
501 if (entries[i] == id)
502 break;
503 }
504 /* record id already in cache, try next */
505 if (i < erst_record_id_cache.len)
506 goto retry;
507 if (erst_record_id_cache.len >= erst_record_id_cache.size) {
508 int new_size;
509 u64 *new_entries;
510
511 new_size = erst_record_id_cache.size * 2;
512 new_size = clamp_val(new_size, ERST_RECORD_ID_CACHE_SIZE_MIN,
513 ERST_RECORD_ID_CACHE_SIZE_MAX);
514 if (new_size <= erst_record_id_cache.size) {
515 if (printk_ratelimit())
516 pr_warn(FW_WARN "too many record IDs!\n");
517 return 0;
518 }
519 new_entries = kvmalloc_array(new_size, sizeof(entries[0]),
520 GFP_KERNEL);
521 if (!new_entries)
522 return -ENOMEM;
523 memcpy(new_entries, entries,
524 erst_record_id_cache.len * sizeof(entries[0]));
525 kvfree(entries);
526 erst_record_id_cache.entries = entries = new_entries;
527 erst_record_id_cache.size = new_size;
528 }
529 entries[i] = id;
530 erst_record_id_cache.len++;
531
532 return 1;
533 }
534
535 /*
536 * Get the record ID of an existing error record on the persistent
537 * storage. If there is no error record on the persistent storage, the
538 * returned record_id is APEI_ERST_INVALID_RECORD_ID.
539 */
erst_get_record_id_next(int * pos,u64 * record_id)540 int erst_get_record_id_next(int *pos, u64 *record_id)
541 {
542 int rc = 0;
543 u64 *entries;
544
545 if (erst_disable)
546 return -ENODEV;
547
548 /* must be enclosed by erst_get_record_id_begin/end */
549 BUG_ON(!erst_record_id_cache.refcount);
550 BUG_ON(*pos < 0 || *pos > erst_record_id_cache.len);
551
552 mutex_lock(&erst_record_id_cache.lock);
553 entries = erst_record_id_cache.entries;
554 for (; *pos < erst_record_id_cache.len; (*pos)++)
555 if (entries[*pos] != APEI_ERST_INVALID_RECORD_ID)
556 break;
557 /* found next record id in cache */
558 if (*pos < erst_record_id_cache.len) {
559 *record_id = entries[*pos];
560 (*pos)++;
561 goto out_unlock;
562 }
563
564 /* Try to add one more record ID to cache */
565 rc = __erst_record_id_cache_add_one();
566 if (rc < 0)
567 goto out_unlock;
568 /* successfully add one new ID */
569 if (rc == 1) {
570 *record_id = erst_record_id_cache.entries[*pos];
571 (*pos)++;
572 rc = 0;
573 } else {
574 *pos = -1;
575 *record_id = APEI_ERST_INVALID_RECORD_ID;
576 }
577 out_unlock:
578 mutex_unlock(&erst_record_id_cache.lock);
579
580 return rc;
581 }
582 EXPORT_SYMBOL_GPL(erst_get_record_id_next);
583
584 /* erst_record_id_cache.lock must be held by caller */
__erst_record_id_cache_compact(void)585 static void __erst_record_id_cache_compact(void)
586 {
587 int i, wpos = 0;
588 u64 *entries;
589
590 if (erst_record_id_cache.refcount)
591 return;
592
593 entries = erst_record_id_cache.entries;
594 for (i = 0; i < erst_record_id_cache.len; i++) {
595 if (entries[i] == APEI_ERST_INVALID_RECORD_ID)
596 continue;
597 if (wpos != i)
598 entries[wpos] = entries[i];
599 wpos++;
600 }
601 erst_record_id_cache.len = wpos;
602 }
603
erst_get_record_id_end(void)604 void erst_get_record_id_end(void)
605 {
606 /*
607 * erst_disable != 0 should be detected by invoker via the
608 * return value of erst_get_record_id_begin/next, so this
609 * function should not be called for erst_disable != 0.
610 */
611 BUG_ON(erst_disable);
612
613 mutex_lock(&erst_record_id_cache.lock);
614 erst_record_id_cache.refcount--;
615 BUG_ON(erst_record_id_cache.refcount < 0);
616 __erst_record_id_cache_compact();
617 mutex_unlock(&erst_record_id_cache.lock);
618 }
619 EXPORT_SYMBOL_GPL(erst_get_record_id_end);
620
__erst_write_to_storage(u64 offset)621 static int __erst_write_to_storage(u64 offset)
622 {
623 struct apei_exec_context ctx;
624 u64 timeout = FIRMWARE_TIMEOUT;
625 u64 val;
626 int rc;
627
628 erst_exec_ctx_init(&ctx);
629 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_WRITE);
630 if (rc)
631 return rc;
632 apei_exec_ctx_set_input(&ctx, offset);
633 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);
634 if (rc)
635 return rc;
636 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
637 if (rc)
638 return rc;
639 for (;;) {
640 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
641 if (rc)
642 return rc;
643 val = apei_exec_ctx_get_output(&ctx);
644 if (!val)
645 break;
646 if (erst_timedout(&timeout, SPIN_UNIT))
647 return -EIO;
648 }
649 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
650 if (rc)
651 return rc;
652 val = apei_exec_ctx_get_output(&ctx);
653 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
654 if (rc)
655 return rc;
656
657 return erst_errno(val);
658 }
659
__erst_read_from_storage(u64 record_id,u64 offset)660 static int __erst_read_from_storage(u64 record_id, u64 offset)
661 {
662 struct apei_exec_context ctx;
663 u64 timeout = FIRMWARE_TIMEOUT;
664 u64 val;
665 int rc;
666
667 erst_exec_ctx_init(&ctx);
668 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_READ);
669 if (rc)
670 return rc;
671 apei_exec_ctx_set_input(&ctx, offset);
672 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);
673 if (rc)
674 return rc;
675 apei_exec_ctx_set_input(&ctx, record_id);
676 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);
677 if (rc)
678 return rc;
679 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
680 if (rc)
681 return rc;
682 for (;;) {
683 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
684 if (rc)
685 return rc;
686 val = apei_exec_ctx_get_output(&ctx);
687 if (!val)
688 break;
689 if (erst_timedout(&timeout, SPIN_UNIT))
690 return -EIO;
691 }
692 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
693 if (rc)
694 return rc;
695 val = apei_exec_ctx_get_output(&ctx);
696 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
697 if (rc)
698 return rc;
699
700 return erst_errno(val);
701 }
702
__erst_clear_from_storage(u64 record_id)703 static int __erst_clear_from_storage(u64 record_id)
704 {
705 struct apei_exec_context ctx;
706 u64 timeout = FIRMWARE_TIMEOUT;
707 u64 val;
708 int rc;
709
710 erst_exec_ctx_init(&ctx);
711 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_CLEAR);
712 if (rc)
713 return rc;
714 apei_exec_ctx_set_input(&ctx, record_id);
715 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);
716 if (rc)
717 return rc;
718 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);
719 if (rc)
720 return rc;
721 for (;;) {
722 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);
723 if (rc)
724 return rc;
725 val = apei_exec_ctx_get_output(&ctx);
726 if (!val)
727 break;
728 if (erst_timedout(&timeout, SPIN_UNIT))
729 return -EIO;
730 }
731 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);
732 if (rc)
733 return rc;
734 val = apei_exec_ctx_get_output(&ctx);
735 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);
736 if (rc)
737 return rc;
738
739 return erst_errno(val);
740 }
741
742 /* NVRAM ERST Error Log Address Range is not supported yet */
pr_unimpl_nvram(void)743 static void pr_unimpl_nvram(void)
744 {
745 if (printk_ratelimit())
746 pr_warn("NVRAM ERST Log Address Range not implemented yet.\n");
747 }
748
__erst_write_to_nvram(const struct cper_record_header * record)749 static int __erst_write_to_nvram(const struct cper_record_header *record)
750 {
751 /* do not print message, because printk is not safe for NMI */
752 return -ENOSYS;
753 }
754
__erst_read_to_erange_from_nvram(u64 record_id,u64 * offset)755 static int __erst_read_to_erange_from_nvram(u64 record_id, u64 *offset)
756 {
757 pr_unimpl_nvram();
758 return -ENOSYS;
759 }
760
__erst_clear_from_nvram(u64 record_id)761 static int __erst_clear_from_nvram(u64 record_id)
762 {
763 pr_unimpl_nvram();
764 return -ENOSYS;
765 }
766
erst_write(const struct cper_record_header * record)767 int erst_write(const struct cper_record_header *record)
768 {
769 int rc;
770 unsigned long flags;
771 struct cper_record_header *rcd_erange;
772
773 if (erst_disable)
774 return -ENODEV;
775
776 if (memcmp(record->signature, CPER_SIG_RECORD, CPER_SIG_SIZE))
777 return -EINVAL;
778
779 if (erst_erange.attr & ERST_RANGE_NVRAM) {
780 if (!raw_spin_trylock_irqsave(&erst_lock, flags))
781 return -EBUSY;
782 rc = __erst_write_to_nvram(record);
783 raw_spin_unlock_irqrestore(&erst_lock, flags);
784 return rc;
785 }
786
787 if (record->record_length > erst_erange.size)
788 return -EINVAL;
789
790 if (!raw_spin_trylock_irqsave(&erst_lock, flags))
791 return -EBUSY;
792 memcpy(erst_erange.vaddr, record, record->record_length);
793 rcd_erange = erst_erange.vaddr;
794 /* signature for serialization system */
795 memcpy(&rcd_erange->persistence_information, "ER", 2);
796
797 rc = __erst_write_to_storage(0);
798 raw_spin_unlock_irqrestore(&erst_lock, flags);
799
800 return rc;
801 }
802 EXPORT_SYMBOL_GPL(erst_write);
803
__erst_read_to_erange(u64 record_id,u64 * offset)804 static int __erst_read_to_erange(u64 record_id, u64 *offset)
805 {
806 int rc;
807
808 if (erst_erange.attr & ERST_RANGE_NVRAM)
809 return __erst_read_to_erange_from_nvram(
810 record_id, offset);
811
812 rc = __erst_read_from_storage(record_id, 0);
813 if (rc)
814 return rc;
815 *offset = 0;
816
817 return 0;
818 }
819
__erst_read(u64 record_id,struct cper_record_header * record,size_t buflen)820 static ssize_t __erst_read(u64 record_id, struct cper_record_header *record,
821 size_t buflen)
822 {
823 int rc;
824 u64 offset, len = 0;
825 struct cper_record_header *rcd_tmp;
826
827 rc = __erst_read_to_erange(record_id, &offset);
828 if (rc)
829 return rc;
830 rcd_tmp = erst_erange.vaddr + offset;
831 len = rcd_tmp->record_length;
832 if (len <= buflen)
833 memcpy(record, rcd_tmp, len);
834
835 return len;
836 }
837
838 /*
839 * If return value > buflen, the buffer size is not big enough,
840 * else if return value < 0, something goes wrong,
841 * else everything is OK, and return value is record length
842 */
erst_read(u64 record_id,struct cper_record_header * record,size_t buflen)843 ssize_t erst_read(u64 record_id, struct cper_record_header *record,
844 size_t buflen)
845 {
846 ssize_t len;
847 unsigned long flags;
848
849 if (erst_disable)
850 return -ENODEV;
851
852 raw_spin_lock_irqsave(&erst_lock, flags);
853 len = __erst_read(record_id, record, buflen);
854 raw_spin_unlock_irqrestore(&erst_lock, flags);
855 return len;
856 }
857 EXPORT_SYMBOL_GPL(erst_read);
858
erst_clear_cache(u64 record_id)859 static void erst_clear_cache(u64 record_id)
860 {
861 int i;
862 u64 *entries;
863
864 mutex_lock(&erst_record_id_cache.lock);
865
866 entries = erst_record_id_cache.entries;
867 for (i = 0; i < erst_record_id_cache.len; i++) {
868 if (entries[i] == record_id)
869 entries[i] = APEI_ERST_INVALID_RECORD_ID;
870 }
871 __erst_record_id_cache_compact();
872
873 mutex_unlock(&erst_record_id_cache.lock);
874 }
875
erst_read_record(u64 record_id,struct cper_record_header * record,size_t buflen,size_t recordlen,const guid_t * creatorid)876 ssize_t erst_read_record(u64 record_id, struct cper_record_header *record,
877 size_t buflen, size_t recordlen, const guid_t *creatorid)
878 {
879 ssize_t len;
880
881 /*
882 * if creatorid is NULL, read any record for erst-dbg module
883 */
884 if (creatorid == NULL) {
885 len = erst_read(record_id, record, buflen);
886 if (len == -ENOENT)
887 erst_clear_cache(record_id);
888
889 return len;
890 }
891
892 len = erst_read(record_id, record, buflen);
893 /*
894 * if erst_read return value is -ENOENT skip to next record_id,
895 * and clear the record_id cache.
896 */
897 if (len == -ENOENT) {
898 erst_clear_cache(record_id);
899 goto out;
900 }
901
902 if (len < 0)
903 goto out;
904
905 /*
906 * if erst_read return value is less than record head length,
907 * consider it as -EIO, and clear the record_id cache.
908 */
909 if (len < recordlen) {
910 len = -EIO;
911 erst_clear_cache(record_id);
912 goto out;
913 }
914
915 /*
916 * if creatorid is not wanted, consider it as not found,
917 * for skipping to next record_id.
918 */
919 if (!guid_equal(&record->creator_id, creatorid))
920 len = -ENOENT;
921
922 out:
923 return len;
924 }
925 EXPORT_SYMBOL_GPL(erst_read_record);
926
erst_clear(u64 record_id)927 int erst_clear(u64 record_id)
928 {
929 int rc, i;
930 unsigned long flags;
931 u64 *entries;
932
933 if (erst_disable)
934 return -ENODEV;
935
936 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);
937 if (rc)
938 return rc;
939 raw_spin_lock_irqsave(&erst_lock, flags);
940 if (erst_erange.attr & ERST_RANGE_NVRAM)
941 rc = __erst_clear_from_nvram(record_id);
942 else
943 rc = __erst_clear_from_storage(record_id);
944 raw_spin_unlock_irqrestore(&erst_lock, flags);
945 if (rc)
946 goto out;
947 entries = erst_record_id_cache.entries;
948 for (i = 0; i < erst_record_id_cache.len; i++) {
949 if (entries[i] == record_id)
950 entries[i] = APEI_ERST_INVALID_RECORD_ID;
951 }
952 __erst_record_id_cache_compact();
953 out:
954 mutex_unlock(&erst_record_id_cache.lock);
955 return rc;
956 }
957 EXPORT_SYMBOL_GPL(erst_clear);
958
setup_erst_disable(char * str)959 static int __init setup_erst_disable(char *str)
960 {
961 erst_disable = 1;
962 return 1;
963 }
964
965 __setup("erst_disable", setup_erst_disable);
966
erst_check_table(struct acpi_table_erst * erst_tab)967 static int erst_check_table(struct acpi_table_erst *erst_tab)
968 {
969 if ((erst_tab->header_length !=
970 (sizeof(struct acpi_table_erst) - sizeof(erst_tab->header)))
971 && (erst_tab->header_length != sizeof(struct acpi_table_erst)))
972 return -EINVAL;
973 if (erst_tab->header.length < sizeof(struct acpi_table_erst))
974 return -EINVAL;
975 if (erst_tab->entries !=
976 (erst_tab->header.length - sizeof(struct acpi_table_erst)) /
977 sizeof(struct acpi_erst_entry))
978 return -EINVAL;
979
980 return 0;
981 }
982
983 static int erst_open_pstore(struct pstore_info *psi);
984 static int erst_close_pstore(struct pstore_info *psi);
985 static ssize_t erst_reader(struct pstore_record *record);
986 static int erst_writer(struct pstore_record *record);
987 static int erst_clearer(struct pstore_record *record);
988
989 static struct pstore_info erst_info = {
990 .owner = THIS_MODULE,
991 .name = "erst",
992 .flags = PSTORE_FLAGS_DMESG,
993 .open = erst_open_pstore,
994 .close = erst_close_pstore,
995 .read = erst_reader,
996 .write = erst_writer,
997 .erase = erst_clearer
998 };
999
1000 #define CPER_CREATOR_PSTORE \
1001 GUID_INIT(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c, \
1002 0x64, 0x90, 0xb8, 0x9d)
1003 #define CPER_SECTION_TYPE_DMESG \
1004 GUID_INIT(0xc197e04e, 0xd545, 0x4a70, 0x9c, 0x17, 0xa5, 0x54, \
1005 0x94, 0x19, 0xeb, 0x12)
1006 #define CPER_SECTION_TYPE_DMESG_Z \
1007 GUID_INIT(0x4f118707, 0x04dd, 0x4055, 0xb5, 0xdd, 0x95, 0x6d, \
1008 0x34, 0xdd, 0xfa, 0xc6)
1009 #define CPER_SECTION_TYPE_MCE \
1010 GUID_INIT(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96, \
1011 0x04, 0x4a, 0x38, 0xfc)
1012
1013 struct cper_pstore_record {
1014 struct cper_record_header hdr;
1015 struct cper_section_descriptor sec_hdr;
1016 char data[];
1017 } __packed;
1018
1019 static int reader_pos;
1020
erst_open_pstore(struct pstore_info * psi)1021 static int erst_open_pstore(struct pstore_info *psi)
1022 {
1023 if (erst_disable)
1024 return -ENODEV;
1025
1026 return erst_get_record_id_begin(&reader_pos);
1027 }
1028
erst_close_pstore(struct pstore_info * psi)1029 static int erst_close_pstore(struct pstore_info *psi)
1030 {
1031 erst_get_record_id_end();
1032
1033 return 0;
1034 }
1035
erst_reader(struct pstore_record * record)1036 static ssize_t erst_reader(struct pstore_record *record)
1037 {
1038 int rc;
1039 ssize_t len = 0;
1040 u64 record_id;
1041 struct cper_pstore_record *rcd;
1042 size_t rcd_len = sizeof(*rcd) + erst_info.bufsize;
1043
1044 if (erst_disable)
1045 return -ENODEV;
1046
1047 rcd = kmalloc(rcd_len, GFP_KERNEL);
1048 if (!rcd) {
1049 rc = -ENOMEM;
1050 goto out;
1051 }
1052 skip:
1053 rc = erst_get_record_id_next(&reader_pos, &record_id);
1054 if (rc)
1055 goto out;
1056
1057 /* no more record */
1058 if (record_id == APEI_ERST_INVALID_RECORD_ID) {
1059 rc = -EINVAL;
1060 goto out;
1061 }
1062
1063 len = erst_read_record(record_id, &rcd->hdr, rcd_len, sizeof(*rcd),
1064 &CPER_CREATOR_PSTORE);
1065 /* The record may be cleared by others, try read next record */
1066 if (len == -ENOENT)
1067 goto skip;
1068 else if (len < 0)
1069 goto out;
1070
1071 record->buf = kmalloc(len, GFP_KERNEL);
1072 if (record->buf == NULL) {
1073 rc = -ENOMEM;
1074 goto out;
1075 }
1076 memcpy(record->buf, rcd->data, len - sizeof(*rcd));
1077 record->id = record_id;
1078 record->compressed = false;
1079 record->ecc_notice_size = 0;
1080 if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_DMESG_Z)) {
1081 record->type = PSTORE_TYPE_DMESG;
1082 record->compressed = true;
1083 } else if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_DMESG))
1084 record->type = PSTORE_TYPE_DMESG;
1085 else if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_MCE))
1086 record->type = PSTORE_TYPE_MCE;
1087 else
1088 record->type = PSTORE_TYPE_MAX;
1089
1090 if (rcd->hdr.validation_bits & CPER_VALID_TIMESTAMP)
1091 record->time.tv_sec = rcd->hdr.timestamp;
1092 else
1093 record->time.tv_sec = 0;
1094 record->time.tv_nsec = 0;
1095
1096 out:
1097 kfree(rcd);
1098 return (rc < 0) ? rc : (len - sizeof(*rcd));
1099 }
1100
erst_writer(struct pstore_record * record)1101 static int erst_writer(struct pstore_record *record)
1102 {
1103 struct cper_pstore_record *rcd = (struct cper_pstore_record *)
1104 (erst_info.buf - sizeof(*rcd));
1105 int ret;
1106
1107 memset(rcd, 0, sizeof(*rcd));
1108 memcpy(rcd->hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE);
1109 rcd->hdr.revision = CPER_RECORD_REV;
1110 rcd->hdr.signature_end = CPER_SIG_END;
1111 rcd->hdr.section_count = 1;
1112 rcd->hdr.error_severity = CPER_SEV_FATAL;
1113 /* timestamp valid. platform_id, partition_id are invalid */
1114 rcd->hdr.validation_bits = CPER_VALID_TIMESTAMP;
1115 rcd->hdr.timestamp = ktime_get_real_seconds();
1116 rcd->hdr.record_length = sizeof(*rcd) + record->size;
1117 rcd->hdr.creator_id = CPER_CREATOR_PSTORE;
1118 rcd->hdr.notification_type = CPER_NOTIFY_MCE;
1119 rcd->hdr.record_id = cper_next_record_id();
1120 rcd->hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR;
1121
1122 rcd->sec_hdr.section_offset = sizeof(*rcd);
1123 rcd->sec_hdr.section_length = record->size;
1124 rcd->sec_hdr.revision = CPER_SEC_REV;
1125 /* fru_id and fru_text is invalid */
1126 rcd->sec_hdr.validation_bits = 0;
1127 rcd->sec_hdr.flags = CPER_SEC_PRIMARY;
1128 switch (record->type) {
1129 case PSTORE_TYPE_DMESG:
1130 if (record->compressed)
1131 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG_Z;
1132 else
1133 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG;
1134 break;
1135 case PSTORE_TYPE_MCE:
1136 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_MCE;
1137 break;
1138 default:
1139 return -EINVAL;
1140 }
1141 rcd->sec_hdr.section_severity = CPER_SEV_FATAL;
1142
1143 ret = erst_write(&rcd->hdr);
1144 record->id = rcd->hdr.record_id;
1145
1146 return ret;
1147 }
1148
erst_clearer(struct pstore_record * record)1149 static int erst_clearer(struct pstore_record *record)
1150 {
1151 return erst_clear(record->id);
1152 }
1153
erst_init(void)1154 static int __init erst_init(void)
1155 {
1156 int rc = 0;
1157 acpi_status status;
1158 struct apei_exec_context ctx;
1159 struct apei_resources erst_resources;
1160 struct resource *r;
1161 char *buf;
1162
1163 if (acpi_disabled)
1164 goto err;
1165
1166 if (erst_disable) {
1167 pr_info(
1168 "Error Record Serialization Table (ERST) support is disabled.\n");
1169 goto err;
1170 }
1171
1172 status = acpi_get_table(ACPI_SIG_ERST, 0,
1173 (struct acpi_table_header **)&erst_tab);
1174 if (status == AE_NOT_FOUND)
1175 goto err;
1176 else if (ACPI_FAILURE(status)) {
1177 const char *msg = acpi_format_exception(status);
1178 pr_err("Failed to get table, %s\n", msg);
1179 rc = -EINVAL;
1180 goto err;
1181 }
1182
1183 rc = erst_check_table(erst_tab);
1184 if (rc) {
1185 pr_err(FW_BUG "ERST table is invalid.\n");
1186 goto err_put_erst_tab;
1187 }
1188
1189 apei_resources_init(&erst_resources);
1190 erst_exec_ctx_init(&ctx);
1191 rc = apei_exec_collect_resources(&ctx, &erst_resources);
1192 if (rc)
1193 goto err_fini;
1194 rc = apei_resources_request(&erst_resources, "APEI ERST");
1195 if (rc)
1196 goto err_fini;
1197 rc = apei_exec_pre_map_gars(&ctx);
1198 if (rc)
1199 goto err_release;
1200 rc = erst_get_erange(&erst_erange);
1201 if (rc) {
1202 if (rc == -ENODEV)
1203 pr_info(
1204 "The corresponding hardware device or firmware implementation "
1205 "is not available.\n");
1206 else
1207 pr_err("Failed to get Error Log Address Range.\n");
1208 goto err_unmap_reg;
1209 }
1210
1211 r = request_mem_region(erst_erange.base, erst_erange.size, "APEI ERST");
1212 if (!r) {
1213 pr_err("Can not request [mem %#010llx-%#010llx] for ERST.\n",
1214 (unsigned long long)erst_erange.base,
1215 (unsigned long long)erst_erange.base + erst_erange.size - 1);
1216 rc = -EIO;
1217 goto err_unmap_reg;
1218 }
1219 rc = -ENOMEM;
1220 erst_erange.vaddr = ioremap_cache(erst_erange.base,
1221 erst_erange.size);
1222 if (!erst_erange.vaddr)
1223 goto err_release_erange;
1224
1225 pr_info(
1226 "Error Record Serialization Table (ERST) support is initialized.\n");
1227
1228 buf = kmalloc(erst_erange.size, GFP_KERNEL);
1229 if (buf) {
1230 erst_info.buf = buf + sizeof(struct cper_pstore_record);
1231 erst_info.bufsize = erst_erange.size -
1232 sizeof(struct cper_pstore_record);
1233 rc = pstore_register(&erst_info);
1234 if (rc) {
1235 if (rc != -EPERM)
1236 pr_info(
1237 "Could not register with persistent store.\n");
1238 erst_info.buf = NULL;
1239 erst_info.bufsize = 0;
1240 kfree(buf);
1241 }
1242 } else
1243 pr_err(
1244 "Failed to allocate %lld bytes for persistent store error log.\n",
1245 erst_erange.size);
1246
1247 /* Cleanup ERST Resources */
1248 apei_resources_fini(&erst_resources);
1249
1250 return 0;
1251
1252 err_release_erange:
1253 release_mem_region(erst_erange.base, erst_erange.size);
1254 err_unmap_reg:
1255 apei_exec_post_unmap_gars(&ctx);
1256 err_release:
1257 apei_resources_release(&erst_resources);
1258 err_fini:
1259 apei_resources_fini(&erst_resources);
1260 err_put_erst_tab:
1261 acpi_put_table((struct acpi_table_header *)erst_tab);
1262 err:
1263 erst_disable = 1;
1264 return rc;
1265 }
1266
1267 device_initcall(erst_init);
1268