1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 2 /****************************************************************************** 3 * 4 * Module Name: psloop - Main AML parse loop 5 * 6 * Copyright (C) 2000 - 2018, Intel Corp. 7 * 8 *****************************************************************************/ 9 10 /* 11 * Parse the AML and build an operation tree as most interpreters, (such as 12 * Perl) do. Parsing is done by hand rather than with a YACC generated parser 13 * to tightly constrain stack and dynamic memory usage. Parsing is kept 14 * flexible and the code fairly compact by parsing based on a list of AML 15 * opcode templates in aml_op_info[]. 16 */ 17 18 #include <acpi/acpi.h> 19 #include "accommon.h" 20 #include "acinterp.h" 21 #include "acparser.h" 22 #include "acdispat.h" 23 #include "amlcode.h" 24 #include "acconvert.h" 25 26 #define _COMPONENT ACPI_PARSER 27 ACPI_MODULE_NAME("psloop") 28 29 /* Local prototypes */ 30 static acpi_status 31 acpi_ps_get_arguments(struct acpi_walk_state *walk_state, 32 u8 * aml_op_start, union acpi_parse_object *op); 33 34 static void 35 acpi_ps_link_module_code(union acpi_parse_object *parent_op, 36 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id); 37 38 /******************************************************************************* 39 * 40 * FUNCTION: acpi_ps_get_arguments 41 * 42 * PARAMETERS: walk_state - Current state 43 * aml_op_start - Op start in AML 44 * op - Current Op 45 * 46 * RETURN: Status 47 * 48 * DESCRIPTION: Get arguments for passed Op. 49 * 50 ******************************************************************************/ 51 52 static acpi_status 53 acpi_ps_get_arguments(struct acpi_walk_state *walk_state, 54 u8 * aml_op_start, union acpi_parse_object *op) 55 { 56 acpi_status status = AE_OK; 57 union acpi_parse_object *arg = NULL; 58 const struct acpi_opcode_info *op_info; 59 60 ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state); 61 62 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 63 "Get arguments for opcode [%s]\n", 64 op->common.aml_op_name)); 65 66 switch (op->common.aml_opcode) { 67 case AML_BYTE_OP: /* AML_BYTEDATA_ARG */ 68 case AML_WORD_OP: /* AML_WORDDATA_ARG */ 69 case AML_DWORD_OP: /* AML_DWORDATA_ARG */ 70 case AML_QWORD_OP: /* AML_QWORDATA_ARG */ 71 case AML_STRING_OP: /* AML_ASCIICHARLIST_ARG */ 72 73 /* Fill in constant or string argument directly */ 74 75 acpi_ps_get_next_simple_arg(&(walk_state->parser_state), 76 GET_CURRENT_ARG_TYPE(walk_state-> 77 arg_types), 78 op); 79 break; 80 81 case AML_INT_NAMEPATH_OP: /* AML_NAMESTRING_ARG */ 82 83 status = acpi_ps_get_next_namepath(walk_state, 84 &(walk_state->parser_state), 85 op, 86 ACPI_POSSIBLE_METHOD_CALL); 87 if (ACPI_FAILURE(status)) { 88 return_ACPI_STATUS(status); 89 } 90 91 walk_state->arg_types = 0; 92 break; 93 94 default: 95 /* 96 * Op is not a constant or string, append each argument to the Op 97 */ 98 while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) && 99 !walk_state->arg_count) { 100 walk_state->aml = walk_state->parser_state.aml; 101 102 switch (op->common.aml_opcode) { 103 case AML_METHOD_OP: 104 case AML_BUFFER_OP: 105 case AML_PACKAGE_OP: 106 case AML_VARIABLE_PACKAGE_OP: 107 case AML_WHILE_OP: 108 109 break; 110 111 default: 112 113 ASL_CV_CAPTURE_COMMENTS(walk_state); 114 break; 115 } 116 117 status = 118 acpi_ps_get_next_arg(walk_state, 119 &(walk_state->parser_state), 120 GET_CURRENT_ARG_TYPE 121 (walk_state->arg_types), &arg); 122 if (ACPI_FAILURE(status)) { 123 return_ACPI_STATUS(status); 124 } 125 126 if (arg) { 127 acpi_ps_append_arg(op, arg); 128 } 129 130 INCREMENT_ARG_LIST(walk_state->arg_types); 131 } 132 133 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 134 "Final argument count: %8.8X pass %u\n", 135 walk_state->arg_count, 136 walk_state->pass_number)); 137 138 /* 139 * This case handles the legacy option that groups all module-level 140 * code blocks together and defers execution until all of the tables 141 * are loaded. Execute all of these blocks at this time. 142 * Execute any module-level code that was detected during the table 143 * load phase. 144 * 145 * Note: this option is deprecated and will be eliminated in the 146 * future. Use of this option can cause problems with AML code that 147 * depends upon in-order immediate execution of module-level code. 148 */ 149 if (acpi_gbl_group_module_level_code && 150 (walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2) && 151 ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) { 152 /* 153 * We want to skip If/Else/While constructs during Pass1 because we 154 * want to actually conditionally execute the code during Pass2. 155 * 156 * Except for disassembly, where we always want to walk the 157 * If/Else/While packages 158 */ 159 switch (op->common.aml_opcode) { 160 case AML_IF_OP: 161 case AML_ELSE_OP: 162 case AML_WHILE_OP: 163 /* 164 * Currently supported module-level opcodes are: 165 * IF/ELSE/WHILE. These appear to be the most common, 166 * and easiest to support since they open an AML 167 * package. 168 */ 169 if (walk_state->pass_number == 170 ACPI_IMODE_LOAD_PASS1) { 171 acpi_ps_link_module_code(op->common. 172 parent, 173 aml_op_start, 174 (u32) 175 (walk_state-> 176 parser_state. 177 pkg_end - 178 aml_op_start), 179 walk_state-> 180 owner_id); 181 } 182 183 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 184 "Pass1: Skipping an If/Else/While body\n")); 185 186 /* Skip body of if/else/while in pass 1 */ 187 188 walk_state->parser_state.aml = 189 walk_state->parser_state.pkg_end; 190 walk_state->arg_count = 0; 191 break; 192 193 default: 194 /* 195 * Check for an unsupported executable opcode at module 196 * level. We must be in PASS1, the parent must be a SCOPE, 197 * The opcode class must be EXECUTE, and the opcode must 198 * not be an argument to another opcode. 199 */ 200 if ((walk_state->pass_number == 201 ACPI_IMODE_LOAD_PASS1) 202 && (op->common.parent->common.aml_opcode == 203 AML_SCOPE_OP)) { 204 op_info = 205 acpi_ps_get_opcode_info(op->common. 206 aml_opcode); 207 if ((op_info->class == 208 AML_CLASS_EXECUTE) && (!arg)) { 209 ACPI_WARNING((AE_INFO, 210 "Unsupported module-level executable opcode " 211 "0x%.2X at table offset 0x%.4X", 212 op->common. 213 aml_opcode, 214 (u32) 215 (ACPI_PTR_DIFF 216 (aml_op_start, 217 walk_state-> 218 parser_state. 219 aml_start) + 220 sizeof(struct 221 acpi_table_header)))); 222 } 223 } 224 break; 225 } 226 } 227 228 /* Special processing for certain opcodes */ 229 230 switch (op->common.aml_opcode) { 231 case AML_METHOD_OP: 232 /* 233 * Skip parsing of control method because we don't have enough 234 * info in the first pass to parse it correctly. 235 * 236 * Save the length and address of the body 237 */ 238 op->named.data = walk_state->parser_state.aml; 239 op->named.length = (u32) 240 (walk_state->parser_state.pkg_end - 241 walk_state->parser_state.aml); 242 243 /* Skip body of method */ 244 245 walk_state->parser_state.aml = 246 walk_state->parser_state.pkg_end; 247 walk_state->arg_count = 0; 248 break; 249 250 case AML_BUFFER_OP: 251 case AML_PACKAGE_OP: 252 case AML_VARIABLE_PACKAGE_OP: 253 254 if ((op->common.parent) && 255 (op->common.parent->common.aml_opcode == 256 AML_NAME_OP) 257 && (walk_state->pass_number <= 258 ACPI_IMODE_LOAD_PASS2)) { 259 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 260 "Setup Package/Buffer: Pass %u, AML Ptr: %p\n", 261 walk_state->pass_number, 262 aml_op_start)); 263 264 /* 265 * Skip parsing of Buffers and Packages because we don't have 266 * enough info in the first pass to parse them correctly. 267 */ 268 op->named.data = aml_op_start; 269 op->named.length = (u32) 270 (walk_state->parser_state.pkg_end - 271 aml_op_start); 272 273 /* Skip body */ 274 275 walk_state->parser_state.aml = 276 walk_state->parser_state.pkg_end; 277 walk_state->arg_count = 0; 278 } 279 break; 280 281 case AML_WHILE_OP: 282 283 if (walk_state->control_state) { 284 walk_state->control_state->control.package_end = 285 walk_state->parser_state.pkg_end; 286 } 287 break; 288 289 default: 290 291 /* No action for all other opcodes */ 292 293 break; 294 } 295 296 break; 297 } 298 299 return_ACPI_STATUS(AE_OK); 300 } 301 302 /******************************************************************************* 303 * 304 * FUNCTION: acpi_ps_link_module_code 305 * 306 * PARAMETERS: parent_op - Parent parser op 307 * aml_start - Pointer to the AML 308 * aml_length - Length of executable AML 309 * owner_id - owner_id of module level code 310 * 311 * RETURN: None. 312 * 313 * DESCRIPTION: Wrap the module-level code with a method object and link the 314 * object to the global list. Note, the mutex field of the method 315 * object is used to link multiple module-level code objects. 316 * 317 * NOTE: In this legacy option, each block of detected executable AML 318 * code that is outside of any control method is wrapped with a temporary 319 * control method object and placed on a global list below. 320 * 321 * This function executes the module-level code for all tables only after 322 * all of the tables have been loaded. It is a legacy option and is 323 * not compatible with other ACPI implementations. See acpi_ns_load_table. 324 * 325 * This function will be removed when the legacy option is removed. 326 * 327 ******************************************************************************/ 328 329 static void 330 acpi_ps_link_module_code(union acpi_parse_object *parent_op, 331 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id) 332 { 333 union acpi_operand_object *prev; 334 union acpi_operand_object *next; 335 union acpi_operand_object *method_obj; 336 struct acpi_namespace_node *parent_node; 337 338 ACPI_FUNCTION_TRACE(ps_link_module_code); 339 340 /* Get the tail of the list */ 341 342 prev = next = acpi_gbl_module_code_list; 343 while (next) { 344 prev = next; 345 next = next->method.mutex; 346 } 347 348 /* 349 * Insert the module level code into the list. Merge it if it is 350 * adjacent to the previous element. 351 */ 352 if (!prev || 353 ((prev->method.aml_start + prev->method.aml_length) != aml_start)) { 354 355 /* Create, initialize, and link a new temporary method object */ 356 357 method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD); 358 if (!method_obj) { 359 return_VOID; 360 } 361 362 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 363 "Create/Link new code block: %p\n", 364 method_obj)); 365 366 if (parent_op->common.node) { 367 parent_node = parent_op->common.node; 368 } else { 369 parent_node = acpi_gbl_root_node; 370 } 371 372 method_obj->method.aml_start = aml_start; 373 method_obj->method.aml_length = aml_length; 374 method_obj->method.owner_id = owner_id; 375 method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL; 376 377 /* 378 * Save the parent node in next_object. This is cheating, but we 379 * don't want to expand the method object. 380 */ 381 method_obj->method.next_object = 382 ACPI_CAST_PTR(union acpi_operand_object, parent_node); 383 384 if (!prev) { 385 acpi_gbl_module_code_list = method_obj; 386 } else { 387 prev->method.mutex = method_obj; 388 } 389 } else { 390 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 391 "Appending to existing code block: %p\n", 392 prev)); 393 394 prev->method.aml_length += aml_length; 395 } 396 397 return_VOID; 398 } 399 400 /******************************************************************************* 401 * 402 * FUNCTION: acpi_ps_parse_loop 403 * 404 * PARAMETERS: walk_state - Current state 405 * 406 * RETURN: Status 407 * 408 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return 409 * a tree of ops. 410 * 411 ******************************************************************************/ 412 413 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state) 414 { 415 acpi_status status = AE_OK; 416 union acpi_parse_object *op = NULL; /* current op */ 417 struct acpi_parse_state *parser_state; 418 u8 *aml_op_start = NULL; 419 420 ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state); 421 422 if (walk_state->descending_callback == NULL) { 423 return_ACPI_STATUS(AE_BAD_PARAMETER); 424 } 425 426 parser_state = &walk_state->parser_state; 427 walk_state->arg_types = 0; 428 429 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY)) 430 431 if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) { 432 433 /* We are restarting a preempted control method */ 434 435 if (acpi_ps_has_completed_scope(parser_state)) { 436 /* 437 * We must check if a predicate to an IF or WHILE statement 438 * was just completed 439 */ 440 if ((parser_state->scope->parse_scope.op) && 441 ((parser_state->scope->parse_scope.op->common. 442 aml_opcode == AML_IF_OP) 443 || (parser_state->scope->parse_scope.op->common. 444 aml_opcode == AML_WHILE_OP)) 445 && (walk_state->control_state) 446 && (walk_state->control_state->common.state == 447 ACPI_CONTROL_PREDICATE_EXECUTING)) { 448 /* 449 * A predicate was just completed, get the value of the 450 * predicate and branch based on that value 451 */ 452 walk_state->op = NULL; 453 status = 454 acpi_ds_get_predicate_value(walk_state, 455 ACPI_TO_POINTER 456 (TRUE)); 457 if (ACPI_FAILURE(status) 458 && ((status & AE_CODE_MASK) != 459 AE_CODE_CONTROL)) { 460 if (status == AE_AML_NO_RETURN_VALUE) { 461 ACPI_EXCEPTION((AE_INFO, status, 462 "Invoked method did not return a value")); 463 } 464 465 ACPI_EXCEPTION((AE_INFO, status, 466 "GetPredicate Failed")); 467 return_ACPI_STATUS(status); 468 } 469 470 status = 471 acpi_ps_next_parse_state(walk_state, op, 472 status); 473 } 474 475 acpi_ps_pop_scope(parser_state, &op, 476 &walk_state->arg_types, 477 &walk_state->arg_count); 478 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 479 "Popped scope, Op=%p\n", op)); 480 } else if (walk_state->prev_op) { 481 482 /* We were in the middle of an op */ 483 484 op = walk_state->prev_op; 485 walk_state->arg_types = walk_state->prev_arg_types; 486 } 487 } 488 #endif 489 490 /* Iterative parsing loop, while there is more AML to process: */ 491 492 while ((parser_state->aml < parser_state->aml_end) || (op)) { 493 ASL_CV_CAPTURE_COMMENTS(walk_state); 494 495 aml_op_start = parser_state->aml; 496 if (!op) { 497 status = 498 acpi_ps_create_op(walk_state, aml_op_start, &op); 499 if (ACPI_FAILURE(status)) { 500 /* 501 * ACPI_PARSE_MODULE_LEVEL means that we are loading a table by 502 * executing it as a control method. However, if we encounter 503 * an error while loading the table, we need to keep trying to 504 * load the table rather than aborting the table load. Set the 505 * status to AE_OK to proceed with the table load. 506 */ 507 if ((walk_state-> 508 parse_flags & ACPI_PARSE_MODULE_LEVEL) 509 && status == AE_ALREADY_EXISTS) { 510 status = AE_OK; 511 } 512 if (status == AE_CTRL_PARSE_CONTINUE) { 513 continue; 514 } 515 516 if (status == AE_CTRL_PARSE_PENDING) { 517 status = AE_OK; 518 } 519 520 if (status == AE_CTRL_TERMINATE) { 521 return_ACPI_STATUS(status); 522 } 523 524 status = 525 acpi_ps_complete_op(walk_state, &op, 526 status); 527 if (ACPI_FAILURE(status)) { 528 return_ACPI_STATUS(status); 529 } 530 if (walk_state->opcode == AML_SCOPE_OP) { 531 /* 532 * If the scope op fails to parse, skip the body of the 533 * scope op because the parse failure indicates that the 534 * device may not exist. 535 */ 536 walk_state->parser_state.aml = 537 walk_state->aml + 1; 538 walk_state->parser_state.aml = 539 acpi_ps_get_next_package_end 540 (&walk_state->parser_state); 541 walk_state->aml = 542 walk_state->parser_state.aml; 543 ACPI_ERROR((AE_INFO, 544 "Skipping Scope block")); 545 } 546 547 continue; 548 } 549 550 acpi_ex_start_trace_opcode(op, walk_state); 551 } 552 553 /* 554 * Start arg_count at zero because we don't know if there are 555 * any args yet 556 */ 557 walk_state->arg_count = 0; 558 559 switch (op->common.aml_opcode) { 560 case AML_BYTE_OP: 561 case AML_WORD_OP: 562 case AML_DWORD_OP: 563 case AML_QWORD_OP: 564 565 break; 566 567 default: 568 569 ASL_CV_CAPTURE_COMMENTS(walk_state); 570 break; 571 } 572 573 /* Are there any arguments that must be processed? */ 574 575 if (walk_state->arg_types) { 576 577 /* Get arguments */ 578 579 status = 580 acpi_ps_get_arguments(walk_state, aml_op_start, op); 581 if (ACPI_FAILURE(status)) { 582 status = 583 acpi_ps_complete_op(walk_state, &op, 584 status); 585 if (ACPI_FAILURE(status)) { 586 return_ACPI_STATUS(status); 587 } 588 if ((walk_state->control_state) && 589 ((walk_state->control_state->control. 590 opcode == AML_IF_OP) 591 || (walk_state->control_state->control. 592 opcode == AML_WHILE_OP))) { 593 /* 594 * If the if/while op fails to parse, we will skip parsing 595 * the body of the op. 596 */ 597 parser_state->aml = 598 walk_state->control_state->control. 599 aml_predicate_start + 1; 600 parser_state->aml = 601 acpi_ps_get_next_package_end 602 (parser_state); 603 walk_state->aml = parser_state->aml; 604 605 ACPI_ERROR((AE_INFO, 606 "Skipping While/If block")); 607 if (*walk_state->aml == AML_ELSE_OP) { 608 ACPI_ERROR((AE_INFO, 609 "Skipping Else block")); 610 walk_state->parser_state.aml = 611 walk_state->aml + 1; 612 walk_state->parser_state.aml = 613 acpi_ps_get_next_package_end 614 (parser_state); 615 walk_state->aml = 616 parser_state->aml; 617 } 618 ACPI_FREE(acpi_ut_pop_generic_state 619 (&walk_state->control_state)); 620 } 621 op = NULL; 622 continue; 623 } 624 } 625 626 /* Check for arguments that need to be processed */ 627 628 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 629 "Parseloop: argument count: %8.8X\n", 630 walk_state->arg_count)); 631 632 if (walk_state->arg_count) { 633 /* 634 * There are arguments (complex ones), push Op and 635 * prepare for argument 636 */ 637 status = acpi_ps_push_scope(parser_state, op, 638 walk_state->arg_types, 639 walk_state->arg_count); 640 if (ACPI_FAILURE(status)) { 641 status = 642 acpi_ps_complete_op(walk_state, &op, 643 status); 644 if (ACPI_FAILURE(status)) { 645 return_ACPI_STATUS(status); 646 } 647 648 continue; 649 } 650 651 op = NULL; 652 continue; 653 } 654 655 /* 656 * All arguments have been processed -- Op is complete, 657 * prepare for next 658 */ 659 walk_state->op_info = 660 acpi_ps_get_opcode_info(op->common.aml_opcode); 661 if (walk_state->op_info->flags & AML_NAMED) { 662 if (op->common.aml_opcode == AML_REGION_OP || 663 op->common.aml_opcode == AML_DATA_REGION_OP) { 664 /* 665 * Skip parsing of control method or opregion body, 666 * because we don't have enough info in the first pass 667 * to parse them correctly. 668 * 669 * Completed parsing an op_region declaration, we now 670 * know the length. 671 */ 672 op->named.length = 673 (u32) (parser_state->aml - op->named.data); 674 } 675 } 676 677 if (walk_state->op_info->flags & AML_CREATE) { 678 /* 679 * Backup to beginning of create_XXXfield declaration (1 for 680 * Opcode) 681 * 682 * body_length is unknown until we parse the body 683 */ 684 op->named.length = 685 (u32) (parser_state->aml - op->named.data); 686 } 687 688 if (op->common.aml_opcode == AML_BANK_FIELD_OP) { 689 /* 690 * Backup to beginning of bank_field declaration 691 * 692 * body_length is unknown until we parse the body 693 */ 694 op->named.length = 695 (u32) (parser_state->aml - op->named.data); 696 } 697 698 /* This op complete, notify the dispatcher */ 699 700 if (walk_state->ascending_callback != NULL) { 701 walk_state->op = op; 702 walk_state->opcode = op->common.aml_opcode; 703 704 status = walk_state->ascending_callback(walk_state); 705 status = 706 acpi_ps_next_parse_state(walk_state, op, status); 707 if (status == AE_CTRL_PENDING) { 708 status = AE_OK; 709 } else 710 if ((walk_state-> 711 parse_flags & ACPI_PARSE_MODULE_LEVEL) 712 && status != AE_CTRL_TRANSFER 713 && ACPI_FAILURE(status)) { 714 /* 715 * ACPI_PARSE_MODULE_LEVEL flag means that we are currently 716 * loading a table by executing it as a control method. 717 * However, if we encounter an error while loading the table, 718 * we need to keep trying to load the table rather than 719 * aborting the table load (setting the status to AE_OK 720 * continues the table load). If we get a failure at this 721 * point, it means that the dispatcher got an error while 722 * processing Op (most likely an AML operand error) or a 723 * control method was called from module level and the 724 * dispatcher returned AE_CTRL_TRANSFER. In the latter case, 725 * leave the status alone, there's nothing wrong with it. 726 */ 727 status = AE_OK; 728 } 729 } 730 731 status = acpi_ps_complete_op(walk_state, &op, status); 732 if (ACPI_FAILURE(status)) { 733 return_ACPI_STATUS(status); 734 } 735 736 } /* while parser_state->Aml */ 737 738 status = acpi_ps_complete_final_op(walk_state, op, status); 739 return_ACPI_STATUS(status); 740 } 741