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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * APEI Error Record Serialization Table support4 *5 * ERST is a way provided by APEI to save and retrieve hardware error6 * information to and from a persistent store.7 *8 * For more information about ERST, please refer to ACPI Specification9 * 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_fmt33#define pr_fmt(fmt) "ERST: " fmt34 35/* ERST command status */36#define ERST_STATUS_SUCCESS 0x037#define ERST_STATUS_NOT_ENOUGH_SPACE 0x138#define ERST_STATUS_HARDWARE_NOT_AVAILABLE 0x239#define ERST_STATUS_FAILED 0x340#define ERST_STATUS_RECORD_STORE_EMPTY 0x441#define ERST_STATUS_RECORD_NOT_FOUND 0x542 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 52int erst_disable;53EXPORT_SYMBOL_GPL(erst_disable);54 55static struct acpi_table_erst *erst_tab;56 57/* ERST Error Log Address Range attributes */58#define ERST_RANGE_RESERVED 0x000159#define ERST_RANGE_NVRAM 0x000260#define ERST_RANGE_SLOW 0x000461 62/* ERST Exec max timings */63#define ERST_EXEC_TIMING_MAX_MASK 0xFFFFFFFF0000000064#define ERST_EXEC_TIMING_MAX_SHIFT 3265 66/*67 * ERST Error Log Address Range, used as buffer for reading/writing68 * error records.69 */70static struct erst_erange {71 u64 base;72 u64 size;73 void __iomem *vaddr;74 u32 attr;75 u64 timings;76} erst_erange;77 78/*79 * Prevent ERST interpreter to run simultaneously, because the80 * corresponding firmware implementation may not work properly when81 * invoked simultaneously.82 *83 * It is used to provide exclusive accessing for ERST Error Log84 * Address Range too.85 */86static DEFINE_RAW_SPINLOCK(erst_lock);87 88static inline int erst_errno(int command_status)89{90 switch (command_status) {91 case ERST_STATUS_SUCCESS:92 return 0;93 case ERST_STATUS_HARDWARE_NOT_AVAILABLE:94 return -ENODEV;95 case ERST_STATUS_NOT_ENOUGH_SPACE:96 return -ENOSPC;97 case ERST_STATUS_RECORD_STORE_EMPTY:98 case ERST_STATUS_RECORD_NOT_FOUND:99 return -ENOENT;100 default:101 return -EINVAL;102 }103}104 105static inline u64 erst_get_timeout(void)106{107 u64 timeout = FIRMWARE_TIMEOUT;108 109 if (erst_erange.attr & ERST_RANGE_SLOW) {110 timeout = ((erst_erange.timings & ERST_EXEC_TIMING_MAX_MASK) >>111 ERST_EXEC_TIMING_MAX_SHIFT) * NSEC_PER_MSEC;112 if (timeout < FIRMWARE_TIMEOUT)113 timeout = FIRMWARE_TIMEOUT;114 }115 return timeout;116}117 118static int erst_timedout(u64 *t, u64 spin_unit)119{120 if ((s64)*t < spin_unit) {121 pr_warn(FW_WARN "Firmware does not respond in time.\n");122 return 1;123 }124 *t -= spin_unit;125 ndelay(spin_unit);126 touch_nmi_watchdog();127 return 0;128}129 130static int erst_exec_load_var1(struct apei_exec_context *ctx,131 struct acpi_whea_header *entry)132{133 return __apei_exec_read_register(entry, &ctx->var1);134}135 136static int erst_exec_load_var2(struct apei_exec_context *ctx,137 struct acpi_whea_header *entry)138{139 return __apei_exec_read_register(entry, &ctx->var2);140}141 142static int erst_exec_store_var1(struct apei_exec_context *ctx,143 struct acpi_whea_header *entry)144{145 return __apei_exec_write_register(entry, ctx->var1);146}147 148static int erst_exec_add(struct apei_exec_context *ctx,149 struct acpi_whea_header *entry)150{151 ctx->var1 += ctx->var2;152 return 0;153}154 155static int erst_exec_subtract(struct apei_exec_context *ctx,156 struct acpi_whea_header *entry)157{158 ctx->var1 -= ctx->var2;159 return 0;160}161 162static int erst_exec_add_value(struct apei_exec_context *ctx,163 struct acpi_whea_header *entry)164{165 int rc;166 u64 val;167 168 rc = __apei_exec_read_register(entry, &val);169 if (rc)170 return rc;171 val += ctx->value;172 rc = __apei_exec_write_register(entry, val);173 return rc;174}175 176static int erst_exec_subtract_value(struct apei_exec_context *ctx,177 struct acpi_whea_header *entry)178{179 int rc;180 u64 val;181 182 rc = __apei_exec_read_register(entry, &val);183 if (rc)184 return rc;185 val -= ctx->value;186 rc = __apei_exec_write_register(entry, val);187 return rc;188}189 190static int erst_exec_stall(struct apei_exec_context *ctx,191 struct acpi_whea_header *entry)192{193 u64 stall_time;194 195 if (ctx->value > FIRMWARE_MAX_STALL) {196 if (!in_nmi())197 pr_warn(FW_WARN198 "Too long stall time for stall instruction: 0x%llx.\n",199 ctx->value);200 stall_time = FIRMWARE_MAX_STALL;201 } else202 stall_time = ctx->value;203 udelay(stall_time);204 return 0;205}206 207static int erst_exec_stall_while_true(struct apei_exec_context *ctx,208 struct acpi_whea_header *entry)209{210 int rc;211 u64 val;212 u64 timeout;213 u64 stall_time;214 215 timeout = erst_get_timeout();216 217 if (ctx->var1 > FIRMWARE_MAX_STALL) {218 if (!in_nmi())219 pr_warn(FW_WARN220 "Too long stall time for stall while true instruction: 0x%llx.\n",221 ctx->var1);222 stall_time = FIRMWARE_MAX_STALL;223 } else224 stall_time = ctx->var1;225 226 for (;;) {227 rc = __apei_exec_read_register(entry, &val);228 if (rc)229 return rc;230 if (val != ctx->value)231 break;232 if (erst_timedout(&timeout, stall_time * NSEC_PER_USEC))233 return -EIO;234 }235 return 0;236}237 238static int erst_exec_skip_next_instruction_if_true(239 struct apei_exec_context *ctx,240 struct acpi_whea_header *entry)241{242 int rc;243 u64 val;244 245 rc = __apei_exec_read_register(entry, &val);246 if (rc)247 return rc;248 if (val == ctx->value) {249 ctx->ip += 2;250 return APEI_EXEC_SET_IP;251 }252 253 return 0;254}255 256static int erst_exec_goto(struct apei_exec_context *ctx,257 struct acpi_whea_header *entry)258{259 ctx->ip = ctx->value;260 return APEI_EXEC_SET_IP;261}262 263static int erst_exec_set_src_address_base(struct apei_exec_context *ctx,264 struct acpi_whea_header *entry)265{266 return __apei_exec_read_register(entry, &ctx->src_base);267}268 269static int erst_exec_set_dst_address_base(struct apei_exec_context *ctx,270 struct acpi_whea_header *entry)271{272 return __apei_exec_read_register(entry, &ctx->dst_base);273}274 275static int erst_exec_move_data(struct apei_exec_context *ctx,276 struct acpi_whea_header *entry)277{278 int rc;279 u64 offset;280 void *src, *dst;281 282 /* ioremap does not work in interrupt context */283 if (in_interrupt()) {284 pr_warn("MOVE_DATA can not be used in interrupt context.\n");285 return -EBUSY;286 }287 288 rc = __apei_exec_read_register(entry, &offset);289 if (rc)290 return rc;291 292 src = ioremap(ctx->src_base + offset, ctx->var2);293 if (!src)294 return -ENOMEM;295 dst = ioremap(ctx->dst_base + offset, ctx->var2);296 if (!dst) {297 iounmap(src);298 return -ENOMEM;299 }300 301 memmove(dst, src, ctx->var2);302 303 iounmap(src);304 iounmap(dst);305 306 return 0;307}308 309static struct apei_exec_ins_type erst_ins_type[] = {310 [ACPI_ERST_READ_REGISTER] = {311 .flags = APEI_EXEC_INS_ACCESS_REGISTER,312 .run = apei_exec_read_register,313 },314 [ACPI_ERST_READ_REGISTER_VALUE] = {315 .flags = APEI_EXEC_INS_ACCESS_REGISTER,316 .run = apei_exec_read_register_value,317 },318 [ACPI_ERST_WRITE_REGISTER] = {319 .flags = APEI_EXEC_INS_ACCESS_REGISTER,320 .run = apei_exec_write_register,321 },322 [ACPI_ERST_WRITE_REGISTER_VALUE] = {323 .flags = APEI_EXEC_INS_ACCESS_REGISTER,324 .run = apei_exec_write_register_value,325 },326 [ACPI_ERST_NOOP] = {327 .flags = 0,328 .run = apei_exec_noop,329 },330 [ACPI_ERST_LOAD_VAR1] = {331 .flags = APEI_EXEC_INS_ACCESS_REGISTER,332 .run = erst_exec_load_var1,333 },334 [ACPI_ERST_LOAD_VAR2] = {335 .flags = APEI_EXEC_INS_ACCESS_REGISTER,336 .run = erst_exec_load_var2,337 },338 [ACPI_ERST_STORE_VAR1] = {339 .flags = APEI_EXEC_INS_ACCESS_REGISTER,340 .run = erst_exec_store_var1,341 },342 [ACPI_ERST_ADD] = {343 .flags = 0,344 .run = erst_exec_add,345 },346 [ACPI_ERST_SUBTRACT] = {347 .flags = 0,348 .run = erst_exec_subtract,349 },350 [ACPI_ERST_ADD_VALUE] = {351 .flags = APEI_EXEC_INS_ACCESS_REGISTER,352 .run = erst_exec_add_value,353 },354 [ACPI_ERST_SUBTRACT_VALUE] = {355 .flags = APEI_EXEC_INS_ACCESS_REGISTER,356 .run = erst_exec_subtract_value,357 },358 [ACPI_ERST_STALL] = {359 .flags = 0,360 .run = erst_exec_stall,361 },362 [ACPI_ERST_STALL_WHILE_TRUE] = {363 .flags = APEI_EXEC_INS_ACCESS_REGISTER,364 .run = erst_exec_stall_while_true,365 },366 [ACPI_ERST_SKIP_NEXT_IF_TRUE] = {367 .flags = APEI_EXEC_INS_ACCESS_REGISTER,368 .run = erst_exec_skip_next_instruction_if_true,369 },370 [ACPI_ERST_GOTO] = {371 .flags = 0,372 .run = erst_exec_goto,373 },374 [ACPI_ERST_SET_SRC_ADDRESS_BASE] = {375 .flags = APEI_EXEC_INS_ACCESS_REGISTER,376 .run = erst_exec_set_src_address_base,377 },378 [ACPI_ERST_SET_DST_ADDRESS_BASE] = {379 .flags = APEI_EXEC_INS_ACCESS_REGISTER,380 .run = erst_exec_set_dst_address_base,381 },382 [ACPI_ERST_MOVE_DATA] = {383 .flags = APEI_EXEC_INS_ACCESS_REGISTER,384 .run = erst_exec_move_data,385 },386};387 388static inline void erst_exec_ctx_init(struct apei_exec_context *ctx)389{390 apei_exec_ctx_init(ctx, erst_ins_type, ARRAY_SIZE(erst_ins_type),391 ERST_TAB_ENTRY(erst_tab), erst_tab->entries);392}393 394static int erst_get_erange(struct erst_erange *range)395{396 struct apei_exec_context ctx;397 int rc;398 399 erst_exec_ctx_init(&ctx);400 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_RANGE);401 if (rc)402 return rc;403 range->base = apei_exec_ctx_get_output(&ctx);404 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_LENGTH);405 if (rc)406 return rc;407 range->size = apei_exec_ctx_get_output(&ctx);408 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_ATTRIBUTES);409 if (rc)410 return rc;411 range->attr = apei_exec_ctx_get_output(&ctx);412 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_TIMINGS);413 if (rc == 0)414 range->timings = apei_exec_ctx_get_output(&ctx);415 else if (rc == -ENOENT)416 range->timings = 0;417 else418 return rc;419 420 return 0;421}422 423static ssize_t __erst_get_record_count(void)424{425 struct apei_exec_context ctx;426 int rc;427 428 erst_exec_ctx_init(&ctx);429 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_COUNT);430 if (rc)431 return rc;432 return apei_exec_ctx_get_output(&ctx);433}434 435ssize_t erst_get_record_count(void)436{437 ssize_t count;438 unsigned long flags;439 440 if (erst_disable)441 return -ENODEV;442 443 raw_spin_lock_irqsave(&erst_lock, flags);444 count = __erst_get_record_count();445 raw_spin_unlock_irqrestore(&erst_lock, flags);446 447 return count;448}449EXPORT_SYMBOL_GPL(erst_get_record_count);450 451#define ERST_RECORD_ID_CACHE_SIZE_MIN 16452#define ERST_RECORD_ID_CACHE_SIZE_MAX 1024453 454struct erst_record_id_cache {455 struct mutex lock;456 u64 *entries;457 int len;458 int size;459 int refcount;460};461 462static struct erst_record_id_cache erst_record_id_cache = {463 .lock = __MUTEX_INITIALIZER(erst_record_id_cache.lock),464 .refcount = 0,465};466 467static int __erst_get_next_record_id(u64 *record_id)468{469 struct apei_exec_context ctx;470 int rc;471 472 erst_exec_ctx_init(&ctx);473 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_ID);474 if (rc)475 return rc;476 *record_id = apei_exec_ctx_get_output(&ctx);477 478 return 0;479}480 481int erst_get_record_id_begin(int *pos)482{483 int rc;484 485 if (erst_disable)486 return -ENODEV;487 488 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);489 if (rc)490 return rc;491 erst_record_id_cache.refcount++;492 mutex_unlock(&erst_record_id_cache.lock);493 494 *pos = 0;495 496 return 0;497}498EXPORT_SYMBOL_GPL(erst_get_record_id_begin);499 500/* erst_record_id_cache.lock must be held by caller */501static int __erst_record_id_cache_add_one(void)502{503 u64 id, prev_id, first_id;504 int i, rc;505 u64 *entries;506 unsigned long flags;507 508 id = prev_id = first_id = APEI_ERST_INVALID_RECORD_ID;509retry:510 raw_spin_lock_irqsave(&erst_lock, flags);511 rc = __erst_get_next_record_id(&id);512 raw_spin_unlock_irqrestore(&erst_lock, flags);513 if (rc == -ENOENT)514 return 0;515 if (rc)516 return rc;517 if (id == APEI_ERST_INVALID_RECORD_ID)518 return 0;519 /* can not skip current ID, or loop back to first ID */520 if (id == prev_id || id == first_id)521 return 0;522 if (first_id == APEI_ERST_INVALID_RECORD_ID)523 first_id = id;524 prev_id = id;525 526 entries = erst_record_id_cache.entries;527 for (i = 0; i < erst_record_id_cache.len; i++) {528 if (entries[i] == id)529 break;530 }531 /* record id already in cache, try next */532 if (i < erst_record_id_cache.len)533 goto retry;534 if (erst_record_id_cache.len >= erst_record_id_cache.size) {535 int new_size;536 u64 *new_entries;537 538 new_size = erst_record_id_cache.size * 2;539 new_size = clamp_val(new_size, ERST_RECORD_ID_CACHE_SIZE_MIN,540 ERST_RECORD_ID_CACHE_SIZE_MAX);541 if (new_size <= erst_record_id_cache.size) {542 if (printk_ratelimit())543 pr_warn(FW_WARN "too many record IDs!\n");544 return 0;545 }546 new_entries = kvmalloc_array(new_size, sizeof(entries[0]),547 GFP_KERNEL);548 if (!new_entries)549 return -ENOMEM;550 memcpy(new_entries, entries,551 erst_record_id_cache.len * sizeof(entries[0]));552 kvfree(entries);553 erst_record_id_cache.entries = entries = new_entries;554 erst_record_id_cache.size = new_size;555 }556 entries[i] = id;557 erst_record_id_cache.len++;558 559 return 1;560}561 562/*563 * Get the record ID of an existing error record on the persistent564 * storage. If there is no error record on the persistent storage, the565 * returned record_id is APEI_ERST_INVALID_RECORD_ID.566 */567int erst_get_record_id_next(int *pos, u64 *record_id)568{569 int rc = 0;570 u64 *entries;571 572 if (erst_disable)573 return -ENODEV;574 575 /* must be enclosed by erst_get_record_id_begin/end */576 BUG_ON(!erst_record_id_cache.refcount);577 BUG_ON(*pos < 0 || *pos > erst_record_id_cache.len);578 579 mutex_lock(&erst_record_id_cache.lock);580 entries = erst_record_id_cache.entries;581 for (; *pos < erst_record_id_cache.len; (*pos)++)582 if (entries[*pos] != APEI_ERST_INVALID_RECORD_ID)583 break;584 /* found next record id in cache */585 if (*pos < erst_record_id_cache.len) {586 *record_id = entries[*pos];587 (*pos)++;588 goto out_unlock;589 }590 591 /* Try to add one more record ID to cache */592 rc = __erst_record_id_cache_add_one();593 if (rc < 0)594 goto out_unlock;595 /* successfully add one new ID */596 if (rc == 1) {597 *record_id = erst_record_id_cache.entries[*pos];598 (*pos)++;599 rc = 0;600 } else {601 *pos = -1;602 *record_id = APEI_ERST_INVALID_RECORD_ID;603 }604out_unlock:605 mutex_unlock(&erst_record_id_cache.lock);606 607 return rc;608}609EXPORT_SYMBOL_GPL(erst_get_record_id_next);610 611/* erst_record_id_cache.lock must be held by caller */612static void __erst_record_id_cache_compact(void)613{614 int i, wpos = 0;615 u64 *entries;616 617 if (erst_record_id_cache.refcount)618 return;619 620 entries = erst_record_id_cache.entries;621 for (i = 0; i < erst_record_id_cache.len; i++) {622 if (entries[i] == APEI_ERST_INVALID_RECORD_ID)623 continue;624 if (wpos != i)625 entries[wpos] = entries[i];626 wpos++;627 }628 erst_record_id_cache.len = wpos;629}630 631void erst_get_record_id_end(void)632{633 /*634 * erst_disable != 0 should be detected by invoker via the635 * return value of erst_get_record_id_begin/next, so this636 * function should not be called for erst_disable != 0.637 */638 BUG_ON(erst_disable);639 640 mutex_lock(&erst_record_id_cache.lock);641 erst_record_id_cache.refcount--;642 BUG_ON(erst_record_id_cache.refcount < 0);643 __erst_record_id_cache_compact();644 mutex_unlock(&erst_record_id_cache.lock);645}646EXPORT_SYMBOL_GPL(erst_get_record_id_end);647 648static int __erst_write_to_storage(u64 offset)649{650 struct apei_exec_context ctx;651 u64 timeout;652 u64 val;653 int rc;654 655 timeout = erst_get_timeout();656 657 erst_exec_ctx_init(&ctx);658 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_WRITE);659 if (rc)660 return rc;661 apei_exec_ctx_set_input(&ctx, offset);662 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);663 if (rc)664 return rc;665 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);666 if (rc)667 return rc;668 for (;;) {669 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);670 if (rc)671 return rc;672 val = apei_exec_ctx_get_output(&ctx);673 if (!val)674 break;675 if (erst_timedout(&timeout, SPIN_UNIT))676 return -EIO;677 }678 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);679 if (rc)680 return rc;681 val = apei_exec_ctx_get_output(&ctx);682 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);683 if (rc)684 return rc;685 686 return erst_errno(val);687}688 689static int __erst_read_from_storage(u64 record_id, u64 offset)690{691 struct apei_exec_context ctx;692 u64 timeout;693 u64 val;694 int rc;695 696 timeout = erst_get_timeout();697 698 erst_exec_ctx_init(&ctx);699 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_READ);700 if (rc)701 return rc;702 apei_exec_ctx_set_input(&ctx, offset);703 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_OFFSET);704 if (rc)705 return rc;706 apei_exec_ctx_set_input(&ctx, record_id);707 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);708 if (rc)709 return rc;710 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);711 if (rc)712 return rc;713 for (;;) {714 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);715 if (rc)716 return rc;717 val = apei_exec_ctx_get_output(&ctx);718 if (!val)719 break;720 if (erst_timedout(&timeout, SPIN_UNIT))721 return -EIO;722 }723 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);724 if (rc)725 return rc;726 val = apei_exec_ctx_get_output(&ctx);727 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);728 if (rc)729 return rc;730 731 return erst_errno(val);732}733 734static int __erst_clear_from_storage(u64 record_id)735{736 struct apei_exec_context ctx;737 u64 timeout;738 u64 val;739 int rc;740 741 timeout = erst_get_timeout();742 743 erst_exec_ctx_init(&ctx);744 rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_CLEAR);745 if (rc)746 return rc;747 apei_exec_ctx_set_input(&ctx, record_id);748 rc = apei_exec_run(&ctx, ACPI_ERST_SET_RECORD_ID);749 if (rc)750 return rc;751 rc = apei_exec_run(&ctx, ACPI_ERST_EXECUTE_OPERATION);752 if (rc)753 return rc;754 for (;;) {755 rc = apei_exec_run(&ctx, ACPI_ERST_CHECK_BUSY_STATUS);756 if (rc)757 return rc;758 val = apei_exec_ctx_get_output(&ctx);759 if (!val)760 break;761 if (erst_timedout(&timeout, SPIN_UNIT))762 return -EIO;763 }764 rc = apei_exec_run(&ctx, ACPI_ERST_GET_COMMAND_STATUS);765 if (rc)766 return rc;767 val = apei_exec_ctx_get_output(&ctx);768 rc = apei_exec_run_optional(&ctx, ACPI_ERST_END);769 if (rc)770 return rc;771 772 return erst_errno(val);773}774 775/* NVRAM ERST Error Log Address Range is not supported yet */776static void pr_unimpl_nvram(void)777{778 if (printk_ratelimit())779 pr_warn("NVRAM ERST Log Address Range not implemented yet.\n");780}781 782static int __erst_write_to_nvram(const struct cper_record_header *record)783{784 /* do not print message, because printk is not safe for NMI */785 return -ENOSYS;786}787 788static int __erst_read_to_erange_from_nvram(u64 record_id, u64 *offset)789{790 pr_unimpl_nvram();791 return -ENOSYS;792}793 794static int __erst_clear_from_nvram(u64 record_id)795{796 pr_unimpl_nvram();797 return -ENOSYS;798}799 800int erst_write(const struct cper_record_header *record)801{802 int rc;803 unsigned long flags;804 struct cper_record_header *rcd_erange;805 806 if (erst_disable)807 return -ENODEV;808 809 if (memcmp(record->signature, CPER_SIG_RECORD, CPER_SIG_SIZE))810 return -EINVAL;811 812 if (erst_erange.attr & ERST_RANGE_NVRAM) {813 if (!raw_spin_trylock_irqsave(&erst_lock, flags))814 return -EBUSY;815 rc = __erst_write_to_nvram(record);816 raw_spin_unlock_irqrestore(&erst_lock, flags);817 return rc;818 }819 820 if (record->record_length > erst_erange.size)821 return -EINVAL;822 823 if (!raw_spin_trylock_irqsave(&erst_lock, flags))824 return -EBUSY;825 memcpy(erst_erange.vaddr, record, record->record_length);826 rcd_erange = erst_erange.vaddr;827 /* signature for serialization system */828 memcpy(&rcd_erange->persistence_information, "ER", 2);829 830 rc = __erst_write_to_storage(0);831 raw_spin_unlock_irqrestore(&erst_lock, flags);832 833 return rc;834}835EXPORT_SYMBOL_GPL(erst_write);836 837static int __erst_read_to_erange(u64 record_id, u64 *offset)838{839 int rc;840 841 if (erst_erange.attr & ERST_RANGE_NVRAM)842 return __erst_read_to_erange_from_nvram(843 record_id, offset);844 845 rc = __erst_read_from_storage(record_id, 0);846 if (rc)847 return rc;848 *offset = 0;849 850 return 0;851}852 853static ssize_t __erst_read(u64 record_id, struct cper_record_header *record,854 size_t buflen)855{856 int rc;857 u64 offset, len = 0;858 struct cper_record_header *rcd_tmp;859 860 rc = __erst_read_to_erange(record_id, &offset);861 if (rc)862 return rc;863 rcd_tmp = erst_erange.vaddr + offset;864 len = rcd_tmp->record_length;865 if (len <= buflen)866 memcpy(record, rcd_tmp, len);867 868 return len;869}870 871/*872 * If return value > buflen, the buffer size is not big enough,873 * else if return value < 0, something goes wrong,874 * else everything is OK, and return value is record length875 */876ssize_t erst_read(u64 record_id, struct cper_record_header *record,877 size_t buflen)878{879 ssize_t len;880 unsigned long flags;881 882 if (erst_disable)883 return -ENODEV;884 885 raw_spin_lock_irqsave(&erst_lock, flags);886 len = __erst_read(record_id, record, buflen);887 raw_spin_unlock_irqrestore(&erst_lock, flags);888 return len;889}890EXPORT_SYMBOL_GPL(erst_read);891 892static void erst_clear_cache(u64 record_id)893{894 int i;895 u64 *entries;896 897 mutex_lock(&erst_record_id_cache.lock);898 899 entries = erst_record_id_cache.entries;900 for (i = 0; i < erst_record_id_cache.len; i++) {901 if (entries[i] == record_id)902 entries[i] = APEI_ERST_INVALID_RECORD_ID;903 }904 __erst_record_id_cache_compact();905 906 mutex_unlock(&erst_record_id_cache.lock);907}908 909ssize_t erst_read_record(u64 record_id, struct cper_record_header *record,910 size_t buflen, size_t recordlen, const guid_t *creatorid)911{912 ssize_t len;913 914 /*915 * if creatorid is NULL, read any record for erst-dbg module916 */917 if (creatorid == NULL) {918 len = erst_read(record_id, record, buflen);919 if (len == -ENOENT)920 erst_clear_cache(record_id);921 922 return len;923 }924 925 len = erst_read(record_id, record, buflen);926 /*927 * if erst_read return value is -ENOENT skip to next record_id,928 * and clear the record_id cache.929 */930 if (len == -ENOENT) {931 erst_clear_cache(record_id);932 goto out;933 }934 935 if (len < 0)936 goto out;937 938 /*939 * if erst_read return value is less than record head length,940 * consider it as -EIO, and clear the record_id cache.941 */942 if (len < recordlen) {943 len = -EIO;944 erst_clear_cache(record_id);945 goto out;946 }947 948 /*949 * if creatorid is not wanted, consider it as not found,950 * for skipping to next record_id.951 */952 if (!guid_equal(&record->creator_id, creatorid))953 len = -ENOENT;954 955out:956 return len;957}958EXPORT_SYMBOL_GPL(erst_read_record);959 960int erst_clear(u64 record_id)961{962 int rc, i;963 unsigned long flags;964 u64 *entries;965 966 if (erst_disable)967 return -ENODEV;968 969 rc = mutex_lock_interruptible(&erst_record_id_cache.lock);970 if (rc)971 return rc;972 raw_spin_lock_irqsave(&erst_lock, flags);973 if (erst_erange.attr & ERST_RANGE_NVRAM)974 rc = __erst_clear_from_nvram(record_id);975 else976 rc = __erst_clear_from_storage(record_id);977 raw_spin_unlock_irqrestore(&erst_lock, flags);978 if (rc)979 goto out;980 entries = erst_record_id_cache.entries;981 for (i = 0; i < erst_record_id_cache.len; i++) {982 if (entries[i] == record_id)983 entries[i] = APEI_ERST_INVALID_RECORD_ID;984 }985 __erst_record_id_cache_compact();986out:987 mutex_unlock(&erst_record_id_cache.lock);988 return rc;989}990EXPORT_SYMBOL_GPL(erst_clear);991 992static int __init setup_erst_disable(char *str)993{994 erst_disable = 1;995 return 1;996}997 998__setup("erst_disable", setup_erst_disable);999 1000static int erst_check_table(struct acpi_table_erst *erst_tab)1001{1002 if ((erst_tab->header_length !=1003 (sizeof(struct acpi_table_erst) - sizeof(erst_tab->header)))1004 && (erst_tab->header_length != sizeof(struct acpi_table_erst)))1005 return -EINVAL;1006 if (erst_tab->header.length < sizeof(struct acpi_table_erst))1007 return -EINVAL;1008 if (erst_tab->entries !=1009 (erst_tab->header.length - sizeof(struct acpi_table_erst)) /1010 sizeof(struct acpi_erst_entry))1011 return -EINVAL;1012 1013 return 0;1014}1015 1016static int erst_open_pstore(struct pstore_info *psi);1017static int erst_close_pstore(struct pstore_info *psi);1018static ssize_t erst_reader(struct pstore_record *record);1019static int erst_writer(struct pstore_record *record);1020static int erst_clearer(struct pstore_record *record);1021 1022static struct pstore_info erst_info = {1023 .owner = THIS_MODULE,1024 .name = "erst",1025 .flags = PSTORE_FLAGS_DMESG,1026 .open = erst_open_pstore,1027 .close = erst_close_pstore,1028 .read = erst_reader,1029 .write = erst_writer,1030 .erase = erst_clearer1031};1032 1033#define CPER_CREATOR_PSTORE \1034 GUID_INIT(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c, \1035 0x64, 0x90, 0xb8, 0x9d)1036#define CPER_SECTION_TYPE_DMESG \1037 GUID_INIT(0xc197e04e, 0xd545, 0x4a70, 0x9c, 0x17, 0xa5, 0x54, \1038 0x94, 0x19, 0xeb, 0x12)1039#define CPER_SECTION_TYPE_DMESG_Z \1040 GUID_INIT(0x4f118707, 0x04dd, 0x4055, 0xb5, 0xdd, 0x95, 0x6d, \1041 0x34, 0xdd, 0xfa, 0xc6)1042#define CPER_SECTION_TYPE_MCE \1043 GUID_INIT(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96, \1044 0x04, 0x4a, 0x38, 0xfc)1045 1046struct cper_pstore_record {1047 struct cper_record_header hdr;1048 struct cper_section_descriptor sec_hdr;1049 char data[];1050} __packed;1051 1052static int reader_pos;1053 1054static int erst_open_pstore(struct pstore_info *psi)1055{1056 if (erst_disable)1057 return -ENODEV;1058 1059 return erst_get_record_id_begin(&reader_pos);1060}1061 1062static int erst_close_pstore(struct pstore_info *psi)1063{1064 erst_get_record_id_end();1065 1066 return 0;1067}1068 1069static ssize_t erst_reader(struct pstore_record *record)1070{1071 int rc;1072 ssize_t len = 0;1073 u64 record_id;1074 struct cper_pstore_record *rcd;1075 size_t rcd_len = sizeof(*rcd) + erst_info.bufsize;1076 1077 if (erst_disable)1078 return -ENODEV;1079 1080 rcd = kmalloc(rcd_len, GFP_KERNEL);1081 if (!rcd) {1082 rc = -ENOMEM;1083 goto out;1084 }1085skip:1086 rc = erst_get_record_id_next(&reader_pos, &record_id);1087 if (rc)1088 goto out;1089 1090 /* no more record */1091 if (record_id == APEI_ERST_INVALID_RECORD_ID) {1092 rc = -EINVAL;1093 goto out;1094 }1095 1096 len = erst_read_record(record_id, &rcd->hdr, rcd_len, sizeof(*rcd),1097 &CPER_CREATOR_PSTORE);1098 /* The record may be cleared by others, try read next record */1099 if (len == -ENOENT)1100 goto skip;1101 else if (len < 0)1102 goto out;1103 1104 record->buf = kmalloc(len, GFP_KERNEL);1105 if (record->buf == NULL) {1106 rc = -ENOMEM;1107 goto out;1108 }1109 memcpy(record->buf, rcd->data, len - sizeof(*rcd));1110 record->id = record_id;1111 record->compressed = false;1112 record->ecc_notice_size = 0;1113 if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_DMESG_Z)) {1114 record->type = PSTORE_TYPE_DMESG;1115 record->compressed = true;1116 } else if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_DMESG))1117 record->type = PSTORE_TYPE_DMESG;1118 else if (guid_equal(&rcd->sec_hdr.section_type, &CPER_SECTION_TYPE_MCE))1119 record->type = PSTORE_TYPE_MCE;1120 else1121 record->type = PSTORE_TYPE_MAX;1122 1123 if (rcd->hdr.validation_bits & CPER_VALID_TIMESTAMP)1124 record->time.tv_sec = rcd->hdr.timestamp;1125 else1126 record->time.tv_sec = 0;1127 record->time.tv_nsec = 0;1128 1129out:1130 kfree(rcd);1131 return (rc < 0) ? rc : (len - sizeof(*rcd));1132}1133 1134static int erst_writer(struct pstore_record *record)1135{1136 struct cper_pstore_record *rcd = (struct cper_pstore_record *)1137 (erst_info.buf - sizeof(*rcd));1138 int ret;1139 1140 memset(rcd, 0, sizeof(*rcd));1141 memcpy(rcd->hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE);1142 rcd->hdr.revision = CPER_RECORD_REV;1143 rcd->hdr.signature_end = CPER_SIG_END;1144 rcd->hdr.section_count = 1;1145 rcd->hdr.error_severity = CPER_SEV_FATAL;1146 /* timestamp valid. platform_id, partition_id are invalid */1147 rcd->hdr.validation_bits = CPER_VALID_TIMESTAMP;1148 rcd->hdr.timestamp = ktime_get_real_seconds();1149 rcd->hdr.record_length = sizeof(*rcd) + record->size;1150 rcd->hdr.creator_id = CPER_CREATOR_PSTORE;1151 rcd->hdr.notification_type = CPER_NOTIFY_MCE;1152 rcd->hdr.record_id = cper_next_record_id();1153 rcd->hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR;1154 1155 rcd->sec_hdr.section_offset = sizeof(*rcd);1156 rcd->sec_hdr.section_length = record->size;1157 rcd->sec_hdr.revision = CPER_SEC_REV;1158 /* fru_id and fru_text is invalid */1159 rcd->sec_hdr.validation_bits = 0;1160 rcd->sec_hdr.flags = CPER_SEC_PRIMARY;1161 switch (record->type) {1162 case PSTORE_TYPE_DMESG:1163 if (record->compressed)1164 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG_Z;1165 else1166 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG;1167 break;1168 case PSTORE_TYPE_MCE:1169 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_MCE;1170 break;1171 default:1172 return -EINVAL;1173 }1174 rcd->sec_hdr.section_severity = CPER_SEV_FATAL;1175 1176 ret = erst_write(&rcd->hdr);1177 record->id = rcd->hdr.record_id;1178 1179 return ret;1180}1181 1182static int erst_clearer(struct pstore_record *record)1183{1184 return erst_clear(record->id);1185}1186 1187static int __init erst_init(void)1188{1189 int rc = 0;1190 acpi_status status;1191 struct apei_exec_context ctx;1192 struct apei_resources erst_resources;1193 struct resource *r;1194 char *buf;1195 1196 if (acpi_disabled)1197 goto err;1198 1199 if (erst_disable) {1200 pr_info(1201 "Error Record Serialization Table (ERST) support is disabled.\n");1202 goto err;1203 }1204 1205 status = acpi_get_table(ACPI_SIG_ERST, 0,1206 (struct acpi_table_header **)&erst_tab);1207 if (status == AE_NOT_FOUND)1208 goto err;1209 else if (ACPI_FAILURE(status)) {1210 const char *msg = acpi_format_exception(status);1211 pr_err("Failed to get table, %s\n", msg);1212 rc = -EINVAL;1213 goto err;1214 }1215 1216 rc = erst_check_table(erst_tab);1217 if (rc) {1218 pr_err(FW_BUG "ERST table is invalid.\n");1219 goto err_put_erst_tab;1220 }1221 1222 apei_resources_init(&erst_resources);1223 erst_exec_ctx_init(&ctx);1224 rc = apei_exec_collect_resources(&ctx, &erst_resources);1225 if (rc)1226 goto err_fini;1227 rc = apei_resources_request(&erst_resources, "APEI ERST");1228 if (rc)1229 goto err_fini;1230 rc = apei_exec_pre_map_gars(&ctx);1231 if (rc)1232 goto err_release;1233 rc = erst_get_erange(&erst_erange);1234 if (rc) {1235 if (rc == -ENODEV)1236 pr_info(1237 "The corresponding hardware device or firmware implementation "1238 "is not available.\n");1239 else1240 pr_err("Failed to get Error Log Address Range.\n");1241 goto err_unmap_reg;1242 }1243 1244 r = request_mem_region(erst_erange.base, erst_erange.size, "APEI ERST");1245 if (!r) {1246 pr_err("Can not request [mem %#010llx-%#010llx] for ERST.\n",1247 (unsigned long long)erst_erange.base,1248 (unsigned long long)erst_erange.base + erst_erange.size - 1);1249 rc = -EIO;1250 goto err_unmap_reg;1251 }1252 rc = -ENOMEM;1253 erst_erange.vaddr = ioremap_cache(erst_erange.base,1254 erst_erange.size);1255 if (!erst_erange.vaddr)1256 goto err_release_erange;1257 1258 pr_info(1259 "Error Record Serialization Table (ERST) support is initialized.\n");1260 1261 buf = kmalloc(erst_erange.size, GFP_KERNEL);1262 if (buf) {1263 erst_info.buf = buf + sizeof(struct cper_pstore_record);1264 erst_info.bufsize = erst_erange.size -1265 sizeof(struct cper_pstore_record);1266 rc = pstore_register(&erst_info);1267 if (rc) {1268 if (rc != -EPERM)1269 pr_info(1270 "Could not register with persistent store.\n");1271 erst_info.buf = NULL;1272 erst_info.bufsize = 0;1273 kfree(buf);1274 }1275 } else1276 pr_err(1277 "Failed to allocate %lld bytes for persistent store error log.\n",1278 erst_erange.size);1279 1280 /* Cleanup ERST Resources */1281 apei_resources_fini(&erst_resources);1282 1283 return 0;1284 1285err_release_erange:1286 release_mem_region(erst_erange.base, erst_erange.size);1287err_unmap_reg:1288 apei_exec_post_unmap_gars(&ctx);1289err_release:1290 apei_resources_release(&erst_resources);1291err_fini:1292 apei_resources_fini(&erst_resources);1293err_put_erst_tab:1294 acpi_put_table((struct acpi_table_header *)erst_tab);1295err:1296 erst_disable = 1;1297 return rc;1298}1299 1300device_initcall(erst_init);1301