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 #undef pr_fmt 43 #define pr_fmt(fmt) "ERST: " fmt 44 45 /* ERST command status */ 46 #define ERST_STATUS_SUCCESS 0x0 47 #define ERST_STATUS_NOT_ENOUGH_SPACE 0x1 48 #define ERST_STATUS_HARDWARE_NOT_AVAILABLE 0x2 49 #define ERST_STATUS_FAILED 0x3 50 #define ERST_STATUS_RECORD_STORE_EMPTY 0x4 51 #define ERST_STATUS_RECORD_NOT_FOUND 0x5 52 53 #define ERST_TAB_ENTRY(tab) \ 54 ((struct acpi_whea_header *)((char *)(tab) + \ 55 sizeof(struct acpi_table_erst))) 56 57 #define SPIN_UNIT 100 /* 100ns */ 58 /* Firmware should respond within 1 milliseconds */ 59 #define FIRMWARE_TIMEOUT (1 * NSEC_PER_MSEC) 60 #define FIRMWARE_MAX_STALL 50 /* 50us */ 61 62 int erst_disable; 63 EXPORT_SYMBOL_GPL(erst_disable); 64 65 static struct acpi_table_erst *erst_tab; 66 67 /* ERST Error Log Address Range atrributes */ 68 #define ERST_RANGE_RESERVED 0x0001 69 #define ERST_RANGE_NVRAM 0x0002 70 #define ERST_RANGE_SLOW 0x0004 71 72 /* 73 * ERST Error Log Address Range, used as buffer for reading/writing 74 * error records. 75 */ 76 static struct erst_erange { 77 u64 base; 78 u64 size; 79 void __iomem *vaddr; 80 u32 attr; 81 } erst_erange; 82 83 /* 84 * Prevent ERST interpreter to run simultaneously, because the 85 * corresponding firmware implementation may not work properly when 86 * invoked simultaneously. 87 * 88 * It is used to provide exclusive accessing for ERST Error Log 89 * Address Range too. 90 */ 91 static DEFINE_RAW_SPINLOCK(erst_lock); 92 93 static inline int erst_errno(int command_status) 94 { 95 switch (command_status) { 96 case ERST_STATUS_SUCCESS: 97 return 0; 98 case ERST_STATUS_HARDWARE_NOT_AVAILABLE: 99 return -ENODEV; 100 case ERST_STATUS_NOT_ENOUGH_SPACE: 101 return -ENOSPC; 102 case ERST_STATUS_RECORD_STORE_EMPTY: 103 case ERST_STATUS_RECORD_NOT_FOUND: 104 return -ENOENT; 105 default: 106 return -EINVAL; 107 } 108 } 109 110 static int erst_timedout(u64 *t, u64 spin_unit) 111 { 112 if ((s64)*t < spin_unit) { 113 pr_warn(FW_WARN "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_warn(FW_WARN 190 "Too long stall time for stall instruction: 0x%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_warn(FW_WARN 210 "Too long stall time for stall while true instruction: 0x%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_warn("MOVE_DATA can not be used in interrupt context.\n"); 275 return -EBUSY; 276 } 277 278 rc = __apei_exec_read_register(entry, &offset); 279 if (rc) 280 return rc; 281 282 src = ioremap(ctx->src_base + offset, ctx->var2); 283 if (!src) 284 return -ENOMEM; 285 dst = ioremap(ctx->dst_base + offset, ctx->var2); 286 if (!dst) { 287 iounmap(src); 288 return -ENOMEM; 289 } 290 291 memmove(dst, src, ctx->var2); 292 293 iounmap(src); 294 iounmap(dst); 295 296 return 0; 297 } 298 299 static struct apei_exec_ins_type erst_ins_type[] = { 300 [ACPI_ERST_READ_REGISTER] = { 301 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 302 .run = apei_exec_read_register, 303 }, 304 [ACPI_ERST_READ_REGISTER_VALUE] = { 305 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 306 .run = apei_exec_read_register_value, 307 }, 308 [ACPI_ERST_WRITE_REGISTER] = { 309 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 310 .run = apei_exec_write_register, 311 }, 312 [ACPI_ERST_WRITE_REGISTER_VALUE] = { 313 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 314 .run = apei_exec_write_register_value, 315 }, 316 [ACPI_ERST_NOOP] = { 317 .flags = 0, 318 .run = apei_exec_noop, 319 }, 320 [ACPI_ERST_LOAD_VAR1] = { 321 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 322 .run = erst_exec_load_var1, 323 }, 324 [ACPI_ERST_LOAD_VAR2] = { 325 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 326 .run = erst_exec_load_var2, 327 }, 328 [ACPI_ERST_STORE_VAR1] = { 329 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 330 .run = erst_exec_store_var1, 331 }, 332 [ACPI_ERST_ADD] = { 333 .flags = 0, 334 .run = erst_exec_add, 335 }, 336 [ACPI_ERST_SUBTRACT] = { 337 .flags = 0, 338 .run = erst_exec_subtract, 339 }, 340 [ACPI_ERST_ADD_VALUE] = { 341 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 342 .run = erst_exec_add_value, 343 }, 344 [ACPI_ERST_SUBTRACT_VALUE] = { 345 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 346 .run = erst_exec_subtract_value, 347 }, 348 [ACPI_ERST_STALL] = { 349 .flags = 0, 350 .run = erst_exec_stall, 351 }, 352 [ACPI_ERST_STALL_WHILE_TRUE] = { 353 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 354 .run = erst_exec_stall_while_true, 355 }, 356 [ACPI_ERST_SKIP_NEXT_IF_TRUE] = { 357 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 358 .run = erst_exec_skip_next_instruction_if_true, 359 }, 360 [ACPI_ERST_GOTO] = { 361 .flags = 0, 362 .run = erst_exec_goto, 363 }, 364 [ACPI_ERST_SET_SRC_ADDRESS_BASE] = { 365 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 366 .run = erst_exec_set_src_address_base, 367 }, 368 [ACPI_ERST_SET_DST_ADDRESS_BASE] = { 369 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 370 .run = erst_exec_set_dst_address_base, 371 }, 372 [ACPI_ERST_MOVE_DATA] = { 373 .flags = APEI_EXEC_INS_ACCESS_REGISTER, 374 .run = erst_exec_move_data, 375 }, 376 }; 377 378 static inline void erst_exec_ctx_init(struct apei_exec_context *ctx) 379 { 380 apei_exec_ctx_init(ctx, erst_ins_type, ARRAY_SIZE(erst_ins_type), 381 ERST_TAB_ENTRY(erst_tab), erst_tab->entries); 382 } 383 384 static int erst_get_erange(struct erst_erange *range) 385 { 386 struct apei_exec_context ctx; 387 int rc; 388 389 erst_exec_ctx_init(&ctx); 390 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_RANGE); 391 if (rc) 392 return rc; 393 range->base = apei_exec_ctx_get_output(&ctx); 394 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_LENGTH); 395 if (rc) 396 return rc; 397 range->size = apei_exec_ctx_get_output(&ctx); 398 rc = apei_exec_run(&ctx, ACPI_ERST_GET_ERROR_ATTRIBUTES); 399 if (rc) 400 return rc; 401 range->attr = apei_exec_ctx_get_output(&ctx); 402 403 return 0; 404 } 405 406 static ssize_t __erst_get_record_count(void) 407 { 408 struct apei_exec_context ctx; 409 int rc; 410 411 erst_exec_ctx_init(&ctx); 412 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_COUNT); 413 if (rc) 414 return rc; 415 return apei_exec_ctx_get_output(&ctx); 416 } 417 418 ssize_t erst_get_record_count(void) 419 { 420 ssize_t count; 421 unsigned long flags; 422 423 if (erst_disable) 424 return -ENODEV; 425 426 raw_spin_lock_irqsave(&erst_lock, flags); 427 count = __erst_get_record_count(); 428 raw_spin_unlock_irqrestore(&erst_lock, flags); 429 430 return count; 431 } 432 EXPORT_SYMBOL_GPL(erst_get_record_count); 433 434 #define ERST_RECORD_ID_CACHE_SIZE_MIN 16 435 #define ERST_RECORD_ID_CACHE_SIZE_MAX 1024 436 437 struct erst_record_id_cache { 438 struct mutex lock; 439 u64 *entries; 440 int len; 441 int size; 442 int refcount; 443 }; 444 445 static struct erst_record_id_cache erst_record_id_cache = { 446 .lock = __MUTEX_INITIALIZER(erst_record_id_cache.lock), 447 .refcount = 0, 448 }; 449 450 static int __erst_get_next_record_id(u64 *record_id) 451 { 452 struct apei_exec_context ctx; 453 int rc; 454 455 erst_exec_ctx_init(&ctx); 456 rc = apei_exec_run(&ctx, ACPI_ERST_GET_RECORD_ID); 457 if (rc) 458 return rc; 459 *record_id = apei_exec_ctx_get_output(&ctx); 460 461 return 0; 462 } 463 464 int erst_get_record_id_begin(int *pos) 465 { 466 int rc; 467 468 if (erst_disable) 469 return -ENODEV; 470 471 rc = mutex_lock_interruptible(&erst_record_id_cache.lock); 472 if (rc) 473 return rc; 474 erst_record_id_cache.refcount++; 475 mutex_unlock(&erst_record_id_cache.lock); 476 477 *pos = 0; 478 479 return 0; 480 } 481 EXPORT_SYMBOL_GPL(erst_get_record_id_begin); 482 483 /* erst_record_id_cache.lock must be held by caller */ 484 static int __erst_record_id_cache_add_one(void) 485 { 486 u64 id, prev_id, first_id; 487 int i, rc; 488 u64 *entries; 489 unsigned long flags; 490 491 id = prev_id = first_id = APEI_ERST_INVALID_RECORD_ID; 492 retry: 493 raw_spin_lock_irqsave(&erst_lock, flags); 494 rc = __erst_get_next_record_id(&id); 495 raw_spin_unlock_irqrestore(&erst_lock, flags); 496 if (rc == -ENOENT) 497 return 0; 498 if (rc) 499 return rc; 500 if (id == APEI_ERST_INVALID_RECORD_ID) 501 return 0; 502 /* can not skip current ID, or loop back to first ID */ 503 if (id == prev_id || id == first_id) 504 return 0; 505 if (first_id == APEI_ERST_INVALID_RECORD_ID) 506 first_id = id; 507 prev_id = id; 508 509 entries = erst_record_id_cache.entries; 510 for (i = 0; i < erst_record_id_cache.len; i++) { 511 if (entries[i] == id) 512 break; 513 } 514 /* record id already in cache, try next */ 515 if (i < erst_record_id_cache.len) 516 goto retry; 517 if (erst_record_id_cache.len >= erst_record_id_cache.size) { 518 int new_size, alloc_size; 519 u64 *new_entries; 520 521 new_size = erst_record_id_cache.size * 2; 522 new_size = clamp_val(new_size, ERST_RECORD_ID_CACHE_SIZE_MIN, 523 ERST_RECORD_ID_CACHE_SIZE_MAX); 524 if (new_size <= erst_record_id_cache.size) { 525 if (printk_ratelimit()) 526 pr_warn(FW_WARN "too many record IDs!\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_warn("NVRAM ERST Log Address Range not implemented yet.\n"); 763 } 764 765 static int __erst_write_to_nvram(const struct cper_record_header *record) 766 { 767 /* do not print message, because printk is not safe for NMI */ 768 return -ENOSYS; 769 } 770 771 static int __erst_read_to_erange_from_nvram(u64 record_id, u64 *offset) 772 { 773 pr_unimpl_nvram(); 774 return -ENOSYS; 775 } 776 777 static int __erst_clear_from_nvram(u64 record_id) 778 { 779 pr_unimpl_nvram(); 780 return -ENOSYS; 781 } 782 783 int erst_write(const struct cper_record_header *record) 784 { 785 int rc; 786 unsigned long flags; 787 struct cper_record_header *rcd_erange; 788 789 if (erst_disable) 790 return -ENODEV; 791 792 if (memcmp(record->signature, CPER_SIG_RECORD, CPER_SIG_SIZE)) 793 return -EINVAL; 794 795 if (erst_erange.attr & ERST_RANGE_NVRAM) { 796 if (!raw_spin_trylock_irqsave(&erst_lock, flags)) 797 return -EBUSY; 798 rc = __erst_write_to_nvram(record); 799 raw_spin_unlock_irqrestore(&erst_lock, flags); 800 return rc; 801 } 802 803 if (record->record_length > erst_erange.size) 804 return -EINVAL; 805 806 if (!raw_spin_trylock_irqsave(&erst_lock, flags)) 807 return -EBUSY; 808 memcpy(erst_erange.vaddr, record, record->record_length); 809 rcd_erange = erst_erange.vaddr; 810 /* signature for serialization system */ 811 memcpy(&rcd_erange->persistence_information, "ER", 2); 812 813 rc = __erst_write_to_storage(0); 814 raw_spin_unlock_irqrestore(&erst_lock, flags); 815 816 return rc; 817 } 818 EXPORT_SYMBOL_GPL(erst_write); 819 820 static int __erst_read_to_erange(u64 record_id, u64 *offset) 821 { 822 int rc; 823 824 if (erst_erange.attr & ERST_RANGE_NVRAM) 825 return __erst_read_to_erange_from_nvram( 826 record_id, offset); 827 828 rc = __erst_read_from_storage(record_id, 0); 829 if (rc) 830 return rc; 831 *offset = 0; 832 833 return 0; 834 } 835 836 static ssize_t __erst_read(u64 record_id, struct cper_record_header *record, 837 size_t buflen) 838 { 839 int rc; 840 u64 offset, len = 0; 841 struct cper_record_header *rcd_tmp; 842 843 rc = __erst_read_to_erange(record_id, &offset); 844 if (rc) 845 return rc; 846 rcd_tmp = erst_erange.vaddr + offset; 847 len = rcd_tmp->record_length; 848 if (len <= buflen) 849 memcpy(record, rcd_tmp, len); 850 851 return len; 852 } 853 854 /* 855 * If return value > buflen, the buffer size is not big enough, 856 * else if return value < 0, something goes wrong, 857 * else everything is OK, and return value is record length 858 */ 859 ssize_t erst_read(u64 record_id, struct cper_record_header *record, 860 size_t buflen) 861 { 862 ssize_t len; 863 unsigned long flags; 864 865 if (erst_disable) 866 return -ENODEV; 867 868 raw_spin_lock_irqsave(&erst_lock, flags); 869 len = __erst_read(record_id, record, buflen); 870 raw_spin_unlock_irqrestore(&erst_lock, flags); 871 return len; 872 } 873 EXPORT_SYMBOL_GPL(erst_read); 874 875 int erst_clear(u64 record_id) 876 { 877 int rc, i; 878 unsigned long flags; 879 u64 *entries; 880 881 if (erst_disable) 882 return -ENODEV; 883 884 rc = mutex_lock_interruptible(&erst_record_id_cache.lock); 885 if (rc) 886 return rc; 887 raw_spin_lock_irqsave(&erst_lock, flags); 888 if (erst_erange.attr & ERST_RANGE_NVRAM) 889 rc = __erst_clear_from_nvram(record_id); 890 else 891 rc = __erst_clear_from_storage(record_id); 892 raw_spin_unlock_irqrestore(&erst_lock, flags); 893 if (rc) 894 goto out; 895 entries = erst_record_id_cache.entries; 896 for (i = 0; i < erst_record_id_cache.len; i++) { 897 if (entries[i] == record_id) 898 entries[i] = APEI_ERST_INVALID_RECORD_ID; 899 } 900 __erst_record_id_cache_compact(); 901 out: 902 mutex_unlock(&erst_record_id_cache.lock); 903 return rc; 904 } 905 EXPORT_SYMBOL_GPL(erst_clear); 906 907 static int __init setup_erst_disable(char *str) 908 { 909 erst_disable = 1; 910 return 0; 911 } 912 913 __setup("erst_disable", setup_erst_disable); 914 915 static int erst_check_table(struct acpi_table_erst *erst_tab) 916 { 917 if ((erst_tab->header_length != 918 (sizeof(struct acpi_table_erst) - sizeof(erst_tab->header))) 919 && (erst_tab->header_length != sizeof(struct acpi_table_erst))) 920 return -EINVAL; 921 if (erst_tab->header.length < sizeof(struct acpi_table_erst)) 922 return -EINVAL; 923 if (erst_tab->entries != 924 (erst_tab->header.length - sizeof(struct acpi_table_erst)) / 925 sizeof(struct acpi_erst_entry)) 926 return -EINVAL; 927 928 return 0; 929 } 930 931 static int erst_open_pstore(struct pstore_info *psi); 932 static int erst_close_pstore(struct pstore_info *psi); 933 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count, 934 struct timespec *time, char **buf, 935 bool *compressed, struct pstore_info *psi); 936 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason, 937 u64 *id, unsigned int part, int count, bool compressed, 938 size_t size, struct pstore_info *psi); 939 static int erst_clearer(enum pstore_type_id type, u64 id, int count, 940 struct timespec time, struct pstore_info *psi); 941 942 static struct pstore_info erst_info = { 943 .owner = THIS_MODULE, 944 .name = "erst", 945 .flags = PSTORE_FLAGS_FRAGILE, 946 .open = erst_open_pstore, 947 .close = erst_close_pstore, 948 .read = erst_reader, 949 .write = erst_writer, 950 .erase = erst_clearer 951 }; 952 953 #define CPER_CREATOR_PSTORE \ 954 UUID_LE(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c, \ 955 0x64, 0x90, 0xb8, 0x9d) 956 #define CPER_SECTION_TYPE_DMESG \ 957 UUID_LE(0xc197e04e, 0xd545, 0x4a70, 0x9c, 0x17, 0xa5, 0x54, \ 958 0x94, 0x19, 0xeb, 0x12) 959 #define CPER_SECTION_TYPE_DMESG_Z \ 960 UUID_LE(0x4f118707, 0x04dd, 0x4055, 0xb5, 0xdd, 0x95, 0x6d, \ 961 0x34, 0xdd, 0xfa, 0xc6) 962 #define CPER_SECTION_TYPE_MCE \ 963 UUID_LE(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96, \ 964 0x04, 0x4a, 0x38, 0xfc) 965 966 struct cper_pstore_record { 967 struct cper_record_header hdr; 968 struct cper_section_descriptor sec_hdr; 969 char data[]; 970 } __packed; 971 972 static int reader_pos; 973 974 static int erst_open_pstore(struct pstore_info *psi) 975 { 976 int rc; 977 978 if (erst_disable) 979 return -ENODEV; 980 981 rc = erst_get_record_id_begin(&reader_pos); 982 983 return rc; 984 } 985 986 static int erst_close_pstore(struct pstore_info *psi) 987 { 988 erst_get_record_id_end(); 989 990 return 0; 991 } 992 993 static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count, 994 struct timespec *time, char **buf, 995 bool *compressed, struct pstore_info *psi) 996 { 997 int rc; 998 ssize_t len = 0; 999 u64 record_id; 1000 struct cper_pstore_record *rcd; 1001 size_t rcd_len = sizeof(*rcd) + erst_info.bufsize; 1002 1003 if (erst_disable) 1004 return -ENODEV; 1005 1006 rcd = kmalloc(rcd_len, GFP_KERNEL); 1007 if (!rcd) { 1008 rc = -ENOMEM; 1009 goto out; 1010 } 1011 skip: 1012 rc = erst_get_record_id_next(&reader_pos, &record_id); 1013 if (rc) 1014 goto out; 1015 1016 /* no more record */ 1017 if (record_id == APEI_ERST_INVALID_RECORD_ID) { 1018 rc = -EINVAL; 1019 goto out; 1020 } 1021 1022 len = erst_read(record_id, &rcd->hdr, rcd_len); 1023 /* The record may be cleared by others, try read next record */ 1024 if (len == -ENOENT) 1025 goto skip; 1026 else if (len < sizeof(*rcd)) { 1027 rc = -EIO; 1028 goto out; 1029 } 1030 if (uuid_le_cmp(rcd->hdr.creator_id, CPER_CREATOR_PSTORE) != 0) 1031 goto skip; 1032 1033 *buf = kmalloc(len, GFP_KERNEL); 1034 if (*buf == NULL) { 1035 rc = -ENOMEM; 1036 goto out; 1037 } 1038 memcpy(*buf, rcd->data, len - sizeof(*rcd)); 1039 *id = record_id; 1040 *compressed = false; 1041 if (uuid_le_cmp(rcd->sec_hdr.section_type, 1042 CPER_SECTION_TYPE_DMESG_Z) == 0) { 1043 *type = PSTORE_TYPE_DMESG; 1044 *compressed = true; 1045 } else if (uuid_le_cmp(rcd->sec_hdr.section_type, 1046 CPER_SECTION_TYPE_DMESG) == 0) 1047 *type = PSTORE_TYPE_DMESG; 1048 else if (uuid_le_cmp(rcd->sec_hdr.section_type, 1049 CPER_SECTION_TYPE_MCE) == 0) 1050 *type = PSTORE_TYPE_MCE; 1051 else 1052 *type = PSTORE_TYPE_UNKNOWN; 1053 1054 if (rcd->hdr.validation_bits & CPER_VALID_TIMESTAMP) 1055 time->tv_sec = rcd->hdr.timestamp; 1056 else 1057 time->tv_sec = 0; 1058 time->tv_nsec = 0; 1059 1060 out: 1061 kfree(rcd); 1062 return (rc < 0) ? rc : (len - sizeof(*rcd)); 1063 } 1064 1065 static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason, 1066 u64 *id, unsigned int part, int count, bool compressed, 1067 size_t size, struct pstore_info *psi) 1068 { 1069 struct cper_pstore_record *rcd = (struct cper_pstore_record *) 1070 (erst_info.buf - sizeof(*rcd)); 1071 int ret; 1072 1073 memset(rcd, 0, sizeof(*rcd)); 1074 memcpy(rcd->hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE); 1075 rcd->hdr.revision = CPER_RECORD_REV; 1076 rcd->hdr.signature_end = CPER_SIG_END; 1077 rcd->hdr.section_count = 1; 1078 rcd->hdr.error_severity = CPER_SEV_FATAL; 1079 /* timestamp valid. platform_id, partition_id are invalid */ 1080 rcd->hdr.validation_bits = CPER_VALID_TIMESTAMP; 1081 rcd->hdr.timestamp = get_seconds(); 1082 rcd->hdr.record_length = sizeof(*rcd) + size; 1083 rcd->hdr.creator_id = CPER_CREATOR_PSTORE; 1084 rcd->hdr.notification_type = CPER_NOTIFY_MCE; 1085 rcd->hdr.record_id = cper_next_record_id(); 1086 rcd->hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR; 1087 1088 rcd->sec_hdr.section_offset = sizeof(*rcd); 1089 rcd->sec_hdr.section_length = size; 1090 rcd->sec_hdr.revision = CPER_SEC_REV; 1091 /* fru_id and fru_text is invalid */ 1092 rcd->sec_hdr.validation_bits = 0; 1093 rcd->sec_hdr.flags = CPER_SEC_PRIMARY; 1094 switch (type) { 1095 case PSTORE_TYPE_DMESG: 1096 if (compressed) 1097 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG_Z; 1098 else 1099 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_DMESG; 1100 break; 1101 case PSTORE_TYPE_MCE: 1102 rcd->sec_hdr.section_type = CPER_SECTION_TYPE_MCE; 1103 break; 1104 default: 1105 return -EINVAL; 1106 } 1107 rcd->sec_hdr.section_severity = CPER_SEV_FATAL; 1108 1109 ret = erst_write(&rcd->hdr); 1110 *id = rcd->hdr.record_id; 1111 1112 return ret; 1113 } 1114 1115 static int erst_clearer(enum pstore_type_id type, u64 id, int count, 1116 struct timespec time, struct pstore_info *psi) 1117 { 1118 return erst_clear(id); 1119 } 1120 1121 static int __init erst_init(void) 1122 { 1123 int rc = 0; 1124 acpi_status status; 1125 struct apei_exec_context ctx; 1126 struct apei_resources erst_resources; 1127 struct resource *r; 1128 char *buf; 1129 1130 if (acpi_disabled) 1131 goto err; 1132 1133 if (erst_disable) { 1134 pr_info( 1135 "Error Record Serialization Table (ERST) support is disabled.\n"); 1136 goto err; 1137 } 1138 1139 status = acpi_get_table(ACPI_SIG_ERST, 0, 1140 (struct acpi_table_header **)&erst_tab); 1141 if (status == AE_NOT_FOUND) 1142 goto err; 1143 else if (ACPI_FAILURE(status)) { 1144 const char *msg = acpi_format_exception(status); 1145 pr_err("Failed to get table, %s\n", msg); 1146 rc = -EINVAL; 1147 goto err; 1148 } 1149 1150 rc = erst_check_table(erst_tab); 1151 if (rc) { 1152 pr_err(FW_BUG "ERST table is invalid.\n"); 1153 goto err; 1154 } 1155 1156 apei_resources_init(&erst_resources); 1157 erst_exec_ctx_init(&ctx); 1158 rc = apei_exec_collect_resources(&ctx, &erst_resources); 1159 if (rc) 1160 goto err_fini; 1161 rc = apei_resources_request(&erst_resources, "APEI ERST"); 1162 if (rc) 1163 goto err_fini; 1164 rc = apei_exec_pre_map_gars(&ctx); 1165 if (rc) 1166 goto err_release; 1167 rc = erst_get_erange(&erst_erange); 1168 if (rc) { 1169 if (rc == -ENODEV) 1170 pr_info( 1171 "The corresponding hardware device or firmware implementation " 1172 "is not available.\n"); 1173 else 1174 pr_err("Failed to get Error Log Address Range.\n"); 1175 goto err_unmap_reg; 1176 } 1177 1178 r = request_mem_region(erst_erange.base, erst_erange.size, "APEI ERST"); 1179 if (!r) { 1180 pr_err("Can not request [mem %#010llx-%#010llx] for ERST.\n", 1181 (unsigned long long)erst_erange.base, 1182 (unsigned long long)erst_erange.base + erst_erange.size - 1); 1183 rc = -EIO; 1184 goto err_unmap_reg; 1185 } 1186 rc = -ENOMEM; 1187 erst_erange.vaddr = ioremap_cache(erst_erange.base, 1188 erst_erange.size); 1189 if (!erst_erange.vaddr) 1190 goto err_release_erange; 1191 1192 pr_info( 1193 "Error Record Serialization Table (ERST) support is initialized.\n"); 1194 1195 buf = kmalloc(erst_erange.size, GFP_KERNEL); 1196 spin_lock_init(&erst_info.buf_lock); 1197 if (buf) { 1198 erst_info.buf = buf + sizeof(struct cper_pstore_record); 1199 erst_info.bufsize = erst_erange.size - 1200 sizeof(struct cper_pstore_record); 1201 rc = pstore_register(&erst_info); 1202 if (rc) { 1203 if (rc != -EPERM) 1204 pr_info( 1205 "Could not register with persistent store.\n"); 1206 erst_info.buf = NULL; 1207 erst_info.bufsize = 0; 1208 kfree(buf); 1209 } 1210 } else 1211 pr_err( 1212 "Failed to allocate %lld bytes for persistent store error log.\n", 1213 erst_erange.size); 1214 1215 return 0; 1216 1217 err_release_erange: 1218 release_mem_region(erst_erange.base, erst_erange.size); 1219 err_unmap_reg: 1220 apei_exec_post_unmap_gars(&ctx); 1221 err_release: 1222 apei_resources_release(&erst_resources); 1223 err_fini: 1224 apei_resources_fini(&erst_resources); 1225 err: 1226 erst_disable = 1; 1227 return rc; 1228 } 1229 1230 device_initcall(erst_init); 1231