1 /****************************************************************************** 2 * 3 * Module Name: psparse - Parser top level AML parse routines 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2008, Intel Corp. 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions, and the following disclaimer, 16 * without modification. 17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 18 * substantially similar to the "NO WARRANTY" disclaimer below 19 * ("Disclaimer") and any redistribution must be conditioned upon 20 * including a substantially similar Disclaimer requirement for further 21 * binary redistribution. 22 * 3. Neither the names of the above-listed copyright holders nor the names 23 * of any contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * Alternatively, this software may be distributed under the terms of the 27 * GNU General Public License ("GPL") version 2 as published by the Free 28 * Software Foundation. 29 * 30 * NO WARRANTY 31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 41 * POSSIBILITY OF SUCH DAMAGES. 42 */ 43 44 /* 45 * Parse the AML and build an operation tree as most interpreters, 46 * like Perl, do. Parsing is done by hand rather than with a YACC 47 * generated parser to tightly constrain stack and dynamic memory 48 * usage. At the same time, parsing is kept flexible and the code 49 * fairly compact by parsing based on a list of AML opcode 50 * templates in aml_op_info[] 51 */ 52 53 #include <acpi/acpi.h> 54 #include "accommon.h" 55 #include "acparser.h" 56 #include "acdispat.h" 57 #include "amlcode.h" 58 #include "acnamesp.h" 59 #include "acinterp.h" 60 61 #define _COMPONENT ACPI_PARSER 62 ACPI_MODULE_NAME("psparse") 63 64 /******************************************************************************* 65 * 66 * FUNCTION: acpi_ps_get_opcode_size 67 * 68 * PARAMETERS: Opcode - An AML opcode 69 * 70 * RETURN: Size of the opcode, in bytes (1 or 2) 71 * 72 * DESCRIPTION: Get the size of the current opcode. 73 * 74 ******************************************************************************/ 75 u32 acpi_ps_get_opcode_size(u32 opcode) 76 { 77 78 /* Extended (2-byte) opcode if > 255 */ 79 80 if (opcode > 0x00FF) { 81 return (2); 82 } 83 84 /* Otherwise, just a single byte opcode */ 85 86 return (1); 87 } 88 89 /******************************************************************************* 90 * 91 * FUNCTION: acpi_ps_peek_opcode 92 * 93 * PARAMETERS: parser_state - A parser state object 94 * 95 * RETURN: Next AML opcode 96 * 97 * DESCRIPTION: Get next AML opcode (without incrementing AML pointer) 98 * 99 ******************************************************************************/ 100 101 u16 acpi_ps_peek_opcode(struct acpi_parse_state * parser_state) 102 { 103 u8 *aml; 104 u16 opcode; 105 106 aml = parser_state->aml; 107 opcode = (u16) ACPI_GET8(aml); 108 109 if (opcode == AML_EXTENDED_OP_PREFIX) { 110 111 /* Extended opcode, get the second opcode byte */ 112 113 aml++; 114 opcode = (u16) ((opcode << 8) | ACPI_GET8(aml)); 115 } 116 117 return (opcode); 118 } 119 120 /******************************************************************************* 121 * 122 * FUNCTION: acpi_ps_complete_this_op 123 * 124 * PARAMETERS: walk_state - Current State 125 * Op - Op to complete 126 * 127 * RETURN: Status 128 * 129 * DESCRIPTION: Perform any cleanup at the completion of an Op. 130 * 131 ******************************************************************************/ 132 133 acpi_status 134 acpi_ps_complete_this_op(struct acpi_walk_state * walk_state, 135 union acpi_parse_object * op) 136 { 137 union acpi_parse_object *prev; 138 union acpi_parse_object *next; 139 const struct acpi_opcode_info *parent_info; 140 union acpi_parse_object *replacement_op = NULL; 141 acpi_status status = AE_OK; 142 143 ACPI_FUNCTION_TRACE_PTR(ps_complete_this_op, op); 144 145 /* Check for null Op, can happen if AML code is corrupt */ 146 147 if (!op) { 148 return_ACPI_STATUS(AE_OK); /* OK for now */ 149 } 150 151 /* Delete this op and the subtree below it if asked to */ 152 153 if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) != 154 ACPI_PARSE_DELETE_TREE) 155 || (walk_state->op_info->class == AML_CLASS_ARGUMENT)) { 156 return_ACPI_STATUS(AE_OK); 157 } 158 159 /* Make sure that we only delete this subtree */ 160 161 if (op->common.parent) { 162 prev = op->common.parent->common.value.arg; 163 if (!prev) { 164 165 /* Nothing more to do */ 166 167 goto cleanup; 168 } 169 170 /* 171 * Check if we need to replace the operator and its subtree 172 * with a return value op (placeholder op) 173 */ 174 parent_info = 175 acpi_ps_get_opcode_info(op->common.parent->common. 176 aml_opcode); 177 178 switch (parent_info->class) { 179 case AML_CLASS_CONTROL: 180 break; 181 182 case AML_CLASS_CREATE: 183 184 /* 185 * These opcodes contain term_arg operands. The current 186 * op must be replaced by a placeholder return op 187 */ 188 replacement_op = 189 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); 190 if (!replacement_op) { 191 status = AE_NO_MEMORY; 192 } 193 break; 194 195 case AML_CLASS_NAMED_OBJECT: 196 197 /* 198 * These opcodes contain term_arg operands. The current 199 * op must be replaced by a placeholder return op 200 */ 201 if ((op->common.parent->common.aml_opcode == 202 AML_REGION_OP) 203 || (op->common.parent->common.aml_opcode == 204 AML_DATA_REGION_OP) 205 || (op->common.parent->common.aml_opcode == 206 AML_BUFFER_OP) 207 || (op->common.parent->common.aml_opcode == 208 AML_PACKAGE_OP) 209 || (op->common.parent->common.aml_opcode == 210 AML_BANK_FIELD_OP) 211 || (op->common.parent->common.aml_opcode == 212 AML_VAR_PACKAGE_OP)) { 213 replacement_op = 214 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); 215 if (!replacement_op) { 216 status = AE_NO_MEMORY; 217 } 218 } else 219 if ((op->common.parent->common.aml_opcode == 220 AML_NAME_OP) 221 && (walk_state->pass_number <= 222 ACPI_IMODE_LOAD_PASS2)) { 223 if ((op->common.aml_opcode == AML_BUFFER_OP) 224 || (op->common.aml_opcode == AML_PACKAGE_OP) 225 || (op->common.aml_opcode == 226 AML_VAR_PACKAGE_OP)) { 227 replacement_op = 228 acpi_ps_alloc_op(op->common. 229 aml_opcode); 230 if (!replacement_op) { 231 status = AE_NO_MEMORY; 232 } else { 233 replacement_op->named.data = 234 op->named.data; 235 replacement_op->named.length = 236 op->named.length; 237 } 238 } 239 } 240 break; 241 242 default: 243 244 replacement_op = 245 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); 246 if (!replacement_op) { 247 status = AE_NO_MEMORY; 248 } 249 } 250 251 /* We must unlink this op from the parent tree */ 252 253 if (prev == op) { 254 255 /* This op is the first in the list */ 256 257 if (replacement_op) { 258 replacement_op->common.parent = 259 op->common.parent; 260 replacement_op->common.value.arg = NULL; 261 replacement_op->common.node = op->common.node; 262 op->common.parent->common.value.arg = 263 replacement_op; 264 replacement_op->common.next = op->common.next; 265 } else { 266 op->common.parent->common.value.arg = 267 op->common.next; 268 } 269 } 270 271 /* Search the parent list */ 272 273 else 274 while (prev) { 275 276 /* Traverse all siblings in the parent's argument list */ 277 278 next = prev->common.next; 279 if (next == op) { 280 if (replacement_op) { 281 replacement_op->common.parent = 282 op->common.parent; 283 replacement_op->common.value. 284 arg = NULL; 285 replacement_op->common.node = 286 op->common.node; 287 prev->common.next = 288 replacement_op; 289 replacement_op->common.next = 290 op->common.next; 291 next = NULL; 292 } else { 293 prev->common.next = 294 op->common.next; 295 next = NULL; 296 } 297 } 298 prev = next; 299 } 300 } 301 302 cleanup: 303 304 /* Now we can actually delete the subtree rooted at Op */ 305 306 acpi_ps_delete_parse_tree(op); 307 return_ACPI_STATUS(status); 308 } 309 310 /******************************************************************************* 311 * 312 * FUNCTION: acpi_ps_next_parse_state 313 * 314 * PARAMETERS: walk_state - Current state 315 * Op - Current parse op 316 * callback_status - Status from previous operation 317 * 318 * RETURN: Status 319 * 320 * DESCRIPTION: Update the parser state based upon the return exception from 321 * the parser callback. 322 * 323 ******************************************************************************/ 324 325 acpi_status 326 acpi_ps_next_parse_state(struct acpi_walk_state *walk_state, 327 union acpi_parse_object *op, 328 acpi_status callback_status) 329 { 330 struct acpi_parse_state *parser_state = &walk_state->parser_state; 331 acpi_status status = AE_CTRL_PENDING; 332 333 ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state, op); 334 335 switch (callback_status) { 336 case AE_CTRL_TERMINATE: 337 /* 338 * A control method was terminated via a RETURN statement. 339 * The walk of this method is complete. 340 */ 341 parser_state->aml = parser_state->aml_end; 342 status = AE_CTRL_TERMINATE; 343 break; 344 345 case AE_CTRL_BREAK: 346 347 parser_state->aml = walk_state->aml_last_while; 348 walk_state->control_state->common.value = FALSE; 349 status = AE_CTRL_BREAK; 350 break; 351 352 case AE_CTRL_CONTINUE: 353 354 parser_state->aml = walk_state->aml_last_while; 355 status = AE_CTRL_CONTINUE; 356 break; 357 358 case AE_CTRL_PENDING: 359 360 parser_state->aml = walk_state->aml_last_while; 361 break; 362 363 #if 0 364 case AE_CTRL_SKIP: 365 366 parser_state->aml = parser_state->scope->parse_scope.pkg_end; 367 status = AE_OK; 368 break; 369 #endif 370 371 case AE_CTRL_TRUE: 372 /* 373 * Predicate of an IF was true, and we are at the matching ELSE. 374 * Just close out this package 375 */ 376 parser_state->aml = acpi_ps_get_next_package_end(parser_state); 377 status = AE_CTRL_PENDING; 378 break; 379 380 case AE_CTRL_FALSE: 381 /* 382 * Either an IF/WHILE Predicate was false or we encountered a BREAK 383 * opcode. In both cases, we do not execute the rest of the 384 * package; We simply close out the parent (finishing the walk of 385 * this branch of the tree) and continue execution at the parent 386 * level. 387 */ 388 parser_state->aml = parser_state->scope->parse_scope.pkg_end; 389 390 /* In the case of a BREAK, just force a predicate (if any) to FALSE */ 391 392 walk_state->control_state->common.value = FALSE; 393 status = AE_CTRL_END; 394 break; 395 396 case AE_CTRL_TRANSFER: 397 398 /* A method call (invocation) -- transfer control */ 399 400 status = AE_CTRL_TRANSFER; 401 walk_state->prev_op = op; 402 walk_state->method_call_op = op; 403 walk_state->method_call_node = 404 (op->common.value.arg)->common.node; 405 406 /* Will return value (if any) be used by the caller? */ 407 408 walk_state->return_used = 409 acpi_ds_is_result_used(op, walk_state); 410 break; 411 412 default: 413 414 status = callback_status; 415 if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) { 416 status = AE_OK; 417 } 418 break; 419 } 420 421 return_ACPI_STATUS(status); 422 } 423 424 /******************************************************************************* 425 * 426 * FUNCTION: acpi_ps_parse_aml 427 * 428 * PARAMETERS: walk_state - Current state 429 * 430 * 431 * RETURN: Status 432 * 433 * DESCRIPTION: Parse raw AML and return a tree of ops 434 * 435 ******************************************************************************/ 436 437 acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state) 438 { 439 acpi_status status; 440 struct acpi_thread_state *thread; 441 struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list; 442 struct acpi_walk_state *previous_walk_state; 443 444 ACPI_FUNCTION_TRACE(ps_parse_aml); 445 446 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 447 "Entered with WalkState=%p Aml=%p size=%X\n", 448 walk_state, walk_state->parser_state.aml, 449 walk_state->parser_state.aml_size)); 450 451 if (!walk_state->parser_state.aml) { 452 return_ACPI_STATUS(AE_NULL_OBJECT); 453 } 454 455 /* Create and initialize a new thread state */ 456 457 thread = acpi_ut_create_thread_state(); 458 if (!thread) { 459 if (walk_state->method_desc) { 460 461 /* Executing a control method - additional cleanup */ 462 463 acpi_ds_terminate_control_method( 464 walk_state->method_desc, walk_state); 465 } 466 467 acpi_ds_delete_walk_state(walk_state); 468 return_ACPI_STATUS(AE_NO_MEMORY); 469 } 470 471 walk_state->thread = thread; 472 473 /* 474 * If executing a method, the starting sync_level is this method's 475 * sync_level 476 */ 477 if (walk_state->method_desc) { 478 walk_state->thread->current_sync_level = 479 walk_state->method_desc->method.sync_level; 480 } 481 482 acpi_ds_push_walk_state(walk_state, thread); 483 484 /* 485 * This global allows the AML debugger to get a handle to the currently 486 * executing control method. 487 */ 488 acpi_gbl_current_walk_list = thread; 489 490 /* 491 * Execute the walk loop as long as there is a valid Walk State. This 492 * handles nested control method invocations without recursion. 493 */ 494 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state)); 495 496 status = AE_OK; 497 while (walk_state) { 498 if (ACPI_SUCCESS(status)) { 499 /* 500 * The parse_loop executes AML until the method terminates 501 * or calls another method. 502 */ 503 status = acpi_ps_parse_loop(walk_state); 504 } 505 506 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 507 "Completed one call to walk loop, %s State=%p\n", 508 acpi_format_exception(status), walk_state)); 509 510 if (status == AE_CTRL_TRANSFER) { 511 /* 512 * A method call was detected. 513 * Transfer control to the called control method 514 */ 515 status = 516 acpi_ds_call_control_method(thread, walk_state, 517 NULL); 518 if (ACPI_FAILURE(status)) { 519 status = 520 acpi_ds_method_error(status, walk_state); 521 } 522 523 /* 524 * If the transfer to the new method method call worked, a new walk 525 * state was created -- get it 526 */ 527 walk_state = acpi_ds_get_current_walk_state(thread); 528 continue; 529 } else if (status == AE_CTRL_TERMINATE) { 530 status = AE_OK; 531 } else if ((status != AE_OK) && (walk_state->method_desc)) { 532 533 /* Either the method parse or actual execution failed */ 534 535 ACPI_ERROR_METHOD("Method parse/execution failed", 536 walk_state->method_node, NULL, 537 status); 538 539 /* Check for possible multi-thread reentrancy problem */ 540 541 if ((status == AE_ALREADY_EXISTS) && 542 (!walk_state->method_desc->method.mutex)) { 543 ACPI_INFO((AE_INFO, 544 "Marking method %4.4s as Serialized because of AE_ALREADY_EXISTS error", 545 walk_state->method_node->name. 546 ascii)); 547 548 /* 549 * Method tried to create an object twice. The probable cause is 550 * that the method cannot handle reentrancy. 551 * 552 * The method is marked not_serialized, but it tried to create 553 * a named object, causing the second thread entrance to fail. 554 * Workaround this problem by marking the method permanently 555 * as Serialized. 556 */ 557 walk_state->method_desc->method.method_flags |= 558 AML_METHOD_SERIALIZED; 559 walk_state->method_desc->method.sync_level = 0; 560 } 561 } 562 563 /* We are done with this walk, move on to the parent if any */ 564 565 walk_state = acpi_ds_pop_walk_state(thread); 566 567 /* Reset the current scope to the beginning of scope stack */ 568 569 acpi_ds_scope_stack_clear(walk_state); 570 571 /* 572 * If we just returned from the execution of a control method or if we 573 * encountered an error during the method parse phase, there's lots of 574 * cleanup to do 575 */ 576 if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == 577 ACPI_PARSE_EXECUTE) || (ACPI_FAILURE(status))) { 578 acpi_ds_terminate_control_method(walk_state-> 579 method_desc, 580 walk_state); 581 } 582 583 /* Delete this walk state and all linked control states */ 584 585 acpi_ps_cleanup_scope(&walk_state->parser_state); 586 previous_walk_state = walk_state; 587 588 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 589 "ReturnValue=%p, ImplicitValue=%p State=%p\n", 590 walk_state->return_desc, 591 walk_state->implicit_return_obj, walk_state)); 592 593 /* Check if we have restarted a preempted walk */ 594 595 walk_state = acpi_ds_get_current_walk_state(thread); 596 if (walk_state) { 597 if (ACPI_SUCCESS(status)) { 598 /* 599 * There is another walk state, restart it. 600 * If the method return value is not used by the parent, 601 * The object is deleted 602 */ 603 if (!previous_walk_state->return_desc) { 604 /* 605 * In slack mode execution, if there is no return value 606 * we should implicitly return zero (0) as a default value. 607 */ 608 if (acpi_gbl_enable_interpreter_slack && 609 !previous_walk_state-> 610 implicit_return_obj) { 611 previous_walk_state-> 612 implicit_return_obj = 613 acpi_ut_create_integer_object 614 ((u64) 0); 615 if (!previous_walk_state-> 616 implicit_return_obj) { 617 return_ACPI_STATUS 618 (AE_NO_MEMORY); 619 } 620 } 621 622 /* Restart the calling control method */ 623 624 status = 625 acpi_ds_restart_control_method 626 (walk_state, 627 previous_walk_state-> 628 implicit_return_obj); 629 } else { 630 /* 631 * We have a valid return value, delete any implicit 632 * return value. 633 */ 634 acpi_ds_clear_implicit_return 635 (previous_walk_state); 636 637 status = 638 acpi_ds_restart_control_method 639 (walk_state, 640 previous_walk_state->return_desc); 641 } 642 if (ACPI_SUCCESS(status)) { 643 walk_state->walk_type |= 644 ACPI_WALK_METHOD_RESTART; 645 } 646 } else { 647 /* On error, delete any return object or implicit return */ 648 649 acpi_ut_remove_reference(previous_walk_state-> 650 return_desc); 651 acpi_ds_clear_implicit_return 652 (previous_walk_state); 653 } 654 } 655 656 /* 657 * Just completed a 1st-level method, save the final internal return 658 * value (if any) 659 */ 660 else if (previous_walk_state->caller_return_desc) { 661 if (previous_walk_state->implicit_return_obj) { 662 *(previous_walk_state->caller_return_desc) = 663 previous_walk_state->implicit_return_obj; 664 } else { 665 /* NULL if no return value */ 666 667 *(previous_walk_state->caller_return_desc) = 668 previous_walk_state->return_desc; 669 } 670 } else { 671 if (previous_walk_state->return_desc) { 672 673 /* Caller doesn't want it, must delete it */ 674 675 acpi_ut_remove_reference(previous_walk_state-> 676 return_desc); 677 } 678 if (previous_walk_state->implicit_return_obj) { 679 680 /* Caller doesn't want it, must delete it */ 681 682 acpi_ut_remove_reference(previous_walk_state-> 683 implicit_return_obj); 684 } 685 } 686 687 acpi_ds_delete_walk_state(previous_walk_state); 688 } 689 690 /* Normal exit */ 691 692 acpi_ex_release_all_mutexes(thread); 693 acpi_ut_delete_generic_state(ACPI_CAST_PTR 694 (union acpi_generic_state, thread)); 695 acpi_gbl_current_walk_list = prev_walk_list; 696 return_ACPI_STATUS(status); 697 } 698