1/****************************************************************************** 2 * 3 * Module Name: psparse - Parser top level AML parse routines 4 * 5 *****************************************************************************/ 6 7/* 8 * Copyright (C) 2000 - 2007, R. Byron Moore 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 <acpi/acparser.h> 55#include <acpi/acdispat.h> 56#include <acpi/amlcode.h> 57#include <acpi/acnamesp.h> 58#include <acpi/acinterp.h> 59 60#define _COMPONENT ACPI_PARSER 61ACPI_MODULE_NAME("psparse") 62 63/******************************************************************************* 64 * 65 * FUNCTION: acpi_ps_get_opcode_size 66 * 67 * PARAMETERS: Opcode - An AML opcode 68 * 69 * RETURN: Size of the opcode, in bytes (1 or 2) 70 * 71 * DESCRIPTION: Get the size of the current opcode. 72 * 73 ******************************************************************************/ 74u32 acpi_ps_get_opcode_size(u32 opcode) 75{ 76 77 /* Extended (2-byte) opcode if > 255 */ 78 79 if (opcode > 0x00FF) { 80 return (2); 81 } 82 83 /* Otherwise, just a single byte opcode */ 84 85 return (1); 86} 87 88/******************************************************************************* 89 * 90 * FUNCTION: acpi_ps_peek_opcode 91 * 92 * PARAMETERS: parser_state - A parser state object 93 * 94 * RETURN: Next AML opcode 95 * 96 * DESCRIPTION: Get next AML opcode (without incrementing AML pointer) 97 * 98 ******************************************************************************/ 99 100u16 acpi_ps_peek_opcode(struct acpi_parse_state * parser_state) 101{ 102 u8 *aml; 103 u16 opcode; 104 105 aml = parser_state->aml; 106 opcode = (u16) ACPI_GET8(aml); 107 108 if (opcode == AML_EXTENDED_OP_PREFIX) { 109 110 /* Extended opcode, get the second opcode byte */ 111 112 aml++; 113 opcode = (u16) ((opcode << 8) | ACPI_GET8(aml)); 114 } 115 116 return (opcode); 117} 118 119/******************************************************************************* 120 * 121 * FUNCTION: acpi_ps_complete_this_op 122 * 123 * PARAMETERS: walk_state - Current State 124 * Op - Op to complete 125 * 126 * RETURN: Status 127 * 128 * DESCRIPTION: Perform any cleanup at the completion of an Op. 129 * 130 ******************************************************************************/ 131 132acpi_status 133acpi_ps_complete_this_op(struct acpi_walk_state * walk_state, 134 union acpi_parse_object * op) 135{ 136 union acpi_parse_object *prev; 137 union acpi_parse_object *next; 138 const struct acpi_opcode_info *parent_info; 139 union acpi_parse_object *replacement_op = NULL; 140 141 ACPI_FUNCTION_TRACE_PTR(ps_complete_this_op, op); 142 143 /* Check for null Op, can happen if AML code is corrupt */ 144 145 if (!op) { 146 return_ACPI_STATUS(AE_OK); /* OK for now */ 147 } 148 149 /* Delete this op and the subtree below it if asked to */ 150 151 if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) != 152 ACPI_PARSE_DELETE_TREE) 153 || (walk_state->op_info->class == AML_CLASS_ARGUMENT)) { 154 return_ACPI_STATUS(AE_OK); 155 } 156 157 /* Make sure that we only delete this subtree */ 158 159 if (op->common.parent) { 160 prev = op->common.parent->common.value.arg; 161 if (!prev) { 162 163 /* Nothing more to do */ 164 165 goto cleanup; 166 } 167 168 /* 169 * Check if we need to replace the operator and its subtree 170 * with a return value op (placeholder op) 171 */ 172 parent_info = 173 acpi_ps_get_opcode_info(op->common.parent->common. 174 aml_opcode); 175 176 switch (parent_info->class) { 177 case AML_CLASS_CONTROL: 178 break; 179 180 case AML_CLASS_CREATE: 181 182 /* 183 * These opcodes contain term_arg operands. The current 184 * op must be replaced by a placeholder return op 185 */ 186 replacement_op = 187 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); 188 if (!replacement_op) { 189 goto allocate_error; 190 } 191 break; 192 193 case AML_CLASS_NAMED_OBJECT: 194 195 /* 196 * These opcodes contain term_arg operands. The current 197 * op must be replaced by a placeholder return op 198 */ 199 if ((op->common.parent->common.aml_opcode == 200 AML_REGION_OP) 201 || (op->common.parent->common.aml_opcode == 202 AML_DATA_REGION_OP) 203 || (op->common.parent->common.aml_opcode == 204 AML_BUFFER_OP) 205 || (op->common.parent->common.aml_opcode == 206 AML_PACKAGE_OP) 207 || (op->common.parent->common.aml_opcode == 208 AML_VAR_PACKAGE_OP)) { 209 replacement_op = 210 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); 211 if (!replacement_op) { 212 goto allocate_error; 213 } 214 } else 215 if ((op->common.parent->common.aml_opcode == 216 AML_NAME_OP) 217 && (walk_state->pass_number <= 218 ACPI_IMODE_LOAD_PASS2)) { 219 if ((op->common.aml_opcode == AML_BUFFER_OP) 220 || (op->common.aml_opcode == AML_PACKAGE_OP) 221 || (op->common.aml_opcode == 222 AML_VAR_PACKAGE_OP)) { 223 replacement_op = 224 acpi_ps_alloc_op(op->common. 225 aml_opcode); 226 if (!replacement_op) { 227 goto allocate_error; 228 } 229 230 replacement_op->named.data = 231 op->named.data; 232 replacement_op->named.length = 233 op->named.length; 234 } 235 } 236 break; 237 238 default: 239 240 replacement_op = 241 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP); 242 if (!replacement_op) { 243 goto allocate_error; 244 } 245 } 246 247 /* We must unlink this op from the parent tree */ 248 249 if (prev == op) { 250 251 /* This op is the first in the list */ 252 253 if (replacement_op) { 254 replacement_op->common.parent = 255 op->common.parent; 256 replacement_op->common.value.arg = NULL; 257 replacement_op->common.node = op->common.node; 258 op->common.parent->common.value.arg = 259 replacement_op; 260 replacement_op->common.next = op->common.next; 261 } else { 262 op->common.parent->common.value.arg = 263 op->common.next; 264 } 265 } 266 267 /* Search the parent list */ 268 269 else 270 while (prev) { 271 272 /* Traverse all siblings in the parent's argument list */ 273 274 next = prev->common.next; 275 if (next == op) { 276 if (replacement_op) { 277 replacement_op->common.parent = 278 op->common.parent; 279 replacement_op->common.value. 280 arg = NULL; 281 replacement_op->common.node = 282 op->common.node; 283 prev->common.next = 284 replacement_op; 285 replacement_op->common.next = 286 op->common.next; 287 next = NULL; 288 } else { 289 prev->common.next = 290 op->common.next; 291 next = NULL; 292 } 293 } 294 prev = next; 295 } 296 } 297 298 cleanup: 299 300 /* Now we can actually delete the subtree rooted at Op */ 301 302 acpi_ps_delete_parse_tree(op); 303 return_ACPI_STATUS(AE_OK); 304 305 allocate_error: 306 307 /* Always delete the subtree, even on error */ 308 309 acpi_ps_delete_parse_tree(op); 310 return_ACPI_STATUS(AE_NO_MEMORY); 311} 312 313/******************************************************************************* 314 * 315 * FUNCTION: acpi_ps_next_parse_state 316 * 317 * PARAMETERS: walk_state - Current state 318 * Op - Current parse op 319 * callback_status - Status from previous operation 320 * 321 * RETURN: Status 322 * 323 * DESCRIPTION: Update the parser state based upon the return exception from 324 * the parser callback. 325 * 326 ******************************************************************************/ 327 328acpi_status 329acpi_ps_next_parse_state(struct acpi_walk_state *walk_state, 330 union acpi_parse_object *op, 331 acpi_status callback_status) 332{ 333 struct acpi_parse_state *parser_state = &walk_state->parser_state; 334 acpi_status status = AE_CTRL_PENDING; 335 336 ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state, op); 337 338 switch (callback_status) { 339 case AE_CTRL_TERMINATE: 340 /* 341 * A control method was terminated via a RETURN statement. 342 * The walk of this method is complete. 343 */ 344 parser_state->aml = parser_state->aml_end; 345 status = AE_CTRL_TERMINATE; 346 break; 347 348 case AE_CTRL_BREAK: 349 350 parser_state->aml = walk_state->aml_last_while; 351 walk_state->control_state->common.value = FALSE; 352 status = acpi_ds_result_stack_pop(walk_state); 353 if (ACPI_SUCCESS(status)) { 354 status = AE_CTRL_BREAK; 355 } 356 break; 357 358 case AE_CTRL_CONTINUE: 359 360 parser_state->aml = walk_state->aml_last_while; 361 status = acpi_ds_result_stack_pop(walk_state); 362 if (ACPI_SUCCESS(status)) { 363 status = AE_CTRL_CONTINUE; 364 } 365 break; 366 367 case AE_CTRL_PENDING: 368 369 parser_state->aml = walk_state->aml_last_while; 370 break; 371 372 373 case AE_CTRL_TRUE: 374 /* 375 * Predicate of an IF was true, and we are at the matching ELSE. 376 * Just close out this package 377 */ 378 parser_state->aml = acpi_ps_get_next_package_end(parser_state); 379 status = acpi_ds_result_stack_pop(walk_state); 380 if (ACPI_SUCCESS(status)) { 381 status = AE_CTRL_PENDING; 382 } 383 break; 384 385 case AE_CTRL_FALSE: 386 /* 387 * Either an IF/WHILE Predicate was false or we encountered a BREAK 388 * opcode. In both cases, we do not execute the rest of the 389 * package; We simply close out the parent (finishing the walk of 390 * this branch of the tree) and continue execution at the parent 391 * level. 392 */ 393 parser_state->aml = parser_state->scope->parse_scope.pkg_end; 394 395 /* In the case of a BREAK, just force a predicate (if any) to FALSE */ 396 397 walk_state->control_state->common.value = FALSE; 398 status = AE_CTRL_END; 399 break; 400 401 case AE_CTRL_TRANSFER: 402 403 /* A method call (invocation) -- transfer control */ 404 405 status = AE_CTRL_TRANSFER; 406 walk_state->prev_op = op; 407 walk_state->method_call_op = op; 408 walk_state->method_call_node = 409 (op->common.value.arg)->common.node; 410 411 /* Will return value (if any) be used by the caller? */ 412 413 walk_state->return_used = 414 acpi_ds_is_result_used(op, walk_state); 415 break; 416 417 default: 418 419 status = callback_status; 420 if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) { 421 status = AE_OK; 422 } 423 break; 424 } 425 426 return_ACPI_STATUS(status); 427} 428 429/******************************************************************************* 430 * 431 * FUNCTION: acpi_ps_parse_aml 432 * 433 * PARAMETERS: walk_state - Current state 434 * 435 * 436 * RETURN: Status 437 * 438 * DESCRIPTION: Parse raw AML and return a tree of ops 439 * 440 ******************************************************************************/ 441 442acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state) 443{ 444 acpi_status status; 445 struct acpi_thread_state *thread; 446 struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list; 447 struct acpi_walk_state *previous_walk_state; 448 449 ACPI_FUNCTION_TRACE(ps_parse_aml); 450 451 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 452 "Entered with WalkState=%p Aml=%p size=%X\n", 453 walk_state, walk_state->parser_state.aml, 454 walk_state->parser_state.aml_size)); 455 456 /* Create and initialize a new thread state */ 457 458 thread = acpi_ut_create_thread_state(); 459 if (!thread) { 460 acpi_ds_delete_walk_state(walk_state); 461 return_ACPI_STATUS(AE_NO_MEMORY); 462 } 463 464 walk_state->thread = thread; 465 466 /* 467 * If executing a method, the starting sync_level is this method's 468 * sync_level 469 */ 470 if (walk_state->method_desc) { 471 walk_state->thread->current_sync_level = 472 walk_state->method_desc->method.sync_level; 473 } 474 475 acpi_ds_push_walk_state(walk_state, thread); 476 477 /* 478 * This global allows the AML debugger to get a handle to the currently 479 * executing control method. 480 */ 481 acpi_gbl_current_walk_list = thread; 482 483 /* 484 * Execute the walk loop as long as there is a valid Walk State. This 485 * handles nested control method invocations without recursion. 486 */ 487 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state)); 488 489 status = AE_OK; 490 while (walk_state) { 491 if (ACPI_SUCCESS(status)) { 492 /* 493 * The parse_loop executes AML until the method terminates 494 * or calls another method. 495 */ 496 status = acpi_ps_parse_loop(walk_state); 497 } 498 499 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 500 "Completed one call to walk loop, %s State=%p\n", 501 acpi_format_exception(status), walk_state)); 502 503 if (status == AE_CTRL_TRANSFER) { 504 /* 505 * A method call was detected. 506 * Transfer control to the called control method 507 */ 508 status = 509 acpi_ds_call_control_method(thread, walk_state, 510 NULL); 511 if (ACPI_FAILURE(status)) { 512 status = 513 acpi_ds_method_error(status, walk_state); 514 } 515 516 /* 517 * If the transfer to the new method method call worked, a new walk 518 * state was created -- get it 519 */ 520 walk_state = acpi_ds_get_current_walk_state(thread); 521 continue; 522 } else if (status == AE_CTRL_TERMINATE) { 523 status = AE_OK; 524 } else if ((status != AE_OK) && (walk_state->method_desc)) { 525 526 /* Either the method parse or actual execution failed */ 527 528 ACPI_ERROR_METHOD("Method parse/execution failed", 529 walk_state->method_node, NULL, 530 status); 531 532 /* Check for possible multi-thread reentrancy problem */ 533 534 if ((status == AE_ALREADY_EXISTS) && 535 (!walk_state->method_desc->method.mutex)) { 536 ACPI_INFO((AE_INFO, 537 "Marking method %4.4s as Serialized", 538 walk_state->method_node->name. 539 ascii)); 540 541 walk_state->method_desc->method.method_flags |= 542 AML_METHOD_SERIALIZED; 543 walk_state->method_desc->method.sync_level = 0; 544 } 545 } 546 547 /* We are done with this walk, move on to the parent if any */ 548 549 walk_state = acpi_ds_pop_walk_state(thread); 550 551 /* Reset the current scope to the beginning of scope stack */ 552 553 acpi_ds_scope_stack_clear(walk_state); 554 555 /* 556 * If we just returned from the execution of a control method or if we 557 * encountered an error during the method parse phase, there's lots of 558 * cleanup to do 559 */ 560 if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == 561 ACPI_PARSE_EXECUTE) || (ACPI_FAILURE(status))) { 562 acpi_ds_terminate_control_method(walk_state-> 563 method_desc, 564 walk_state); 565 } 566 567 /* Delete this walk state and all linked control states */ 568 569 acpi_ps_cleanup_scope(&walk_state->parser_state); 570 previous_walk_state = walk_state; 571 572 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 573 "ReturnValue=%p, ImplicitValue=%p State=%p\n", 574 walk_state->return_desc, 575 walk_state->implicit_return_obj, walk_state)); 576 577 /* Check if we have restarted a preempted walk */ 578 579 walk_state = acpi_ds_get_current_walk_state(thread); 580 if (walk_state) { 581 if (ACPI_SUCCESS(status)) { 582 /* 583 * There is another walk state, restart it. 584 * If the method return value is not used by the parent, 585 * The object is deleted 586 */ 587 if (!previous_walk_state->return_desc) { 588 status = 589 acpi_ds_restart_control_method 590 (walk_state, 591 previous_walk_state-> 592 implicit_return_obj); 593 } else { 594 /* 595 * We have a valid return value, delete any implicit 596 * return value. 597 */ 598 acpi_ds_clear_implicit_return 599 (previous_walk_state); 600 601 status = 602 acpi_ds_restart_control_method 603 (walk_state, 604 previous_walk_state->return_desc); 605 } 606 if (ACPI_SUCCESS(status)) { 607 walk_state->walk_type |= 608 ACPI_WALK_METHOD_RESTART; 609 } 610 } else { 611 /* On error, delete any return object */ 612 613 acpi_ut_remove_reference(previous_walk_state-> 614 return_desc); 615 } 616 } 617 618 /* 619 * Just completed a 1st-level method, save the final internal return 620 * value (if any) 621 */ 622 else if (previous_walk_state->caller_return_desc) { 623 if (previous_walk_state->implicit_return_obj) { 624 *(previous_walk_state->caller_return_desc) = 625 previous_walk_state->implicit_return_obj; 626 } else { 627 /* NULL if no return value */ 628 629 *(previous_walk_state->caller_return_desc) = 630 previous_walk_state->return_desc; 631 } 632 } else { 633 if (previous_walk_state->return_desc) { 634 635 /* Caller doesn't want it, must delete it */ 636 637 acpi_ut_remove_reference(previous_walk_state-> 638 return_desc); 639 } 640 if (previous_walk_state->implicit_return_obj) { 641 642 /* Caller doesn't want it, must delete it */ 643 644 acpi_ut_remove_reference(previous_walk_state-> 645 implicit_return_obj); 646 } 647 } 648 649 acpi_ds_delete_walk_state(previous_walk_state); 650 } 651 652 /* Normal exit */ 653 654 acpi_ex_release_all_mutexes(thread); 655 acpi_ut_delete_generic_state(ACPI_CAST_PTR 656 (union acpi_generic_state, thread)); 657 acpi_gbl_current_walk_list = prev_walk_list; 658 return_ACPI_STATUS(status); 659} 660