1 /****************************************************************************** 2 * 3 * Module Name: psloop - Main AML parse loop 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2020, 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, (such as 46 * Perl) do. Parsing is done by hand rather than with a YACC generated parser 47 * to tightly constrain stack and dynamic memory usage. Parsing is kept 48 * flexible and the code fairly compact by parsing based on a list of AML 49 * opcode templates in AmlOpInfo[]. 50 */ 51 52 #include "acpi.h" 53 #include "accommon.h" 54 #include "acinterp.h" 55 #include "acparser.h" 56 #include "acdispat.h" 57 #include "amlcode.h" 58 #include "acconvert.h" 59 #include "acnamesp.h" 60 61 #define _COMPONENT ACPI_PARSER 62 ACPI_MODULE_NAME ("psloop") 63 64 65 /* Local prototypes */ 66 67 static ACPI_STATUS 68 AcpiPsGetArguments ( 69 ACPI_WALK_STATE *WalkState, 70 UINT8 *AmlOpStart, 71 ACPI_PARSE_OBJECT *Op); 72 73 74 /******************************************************************************* 75 * 76 * FUNCTION: AcpiPsGetArguments 77 * 78 * PARAMETERS: WalkState - Current state 79 * AmlOpStart - Op start in AML 80 * Op - Current Op 81 * 82 * RETURN: Status 83 * 84 * DESCRIPTION: Get arguments for passed Op. 85 * 86 ******************************************************************************/ 87 88 static ACPI_STATUS 89 AcpiPsGetArguments ( 90 ACPI_WALK_STATE *WalkState, 91 UINT8 *AmlOpStart, 92 ACPI_PARSE_OBJECT *Op) 93 { 94 ACPI_STATUS Status = AE_OK; 95 ACPI_PARSE_OBJECT *Arg = NULL; 96 97 98 ACPI_FUNCTION_TRACE_PTR (PsGetArguments, WalkState); 99 100 101 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, 102 "Get arguments for opcode [%s]\n", Op->Common.AmlOpName)); 103 104 switch (Op->Common.AmlOpcode) 105 { 106 case AML_BYTE_OP: /* AML_BYTEDATA_ARG */ 107 case AML_WORD_OP: /* AML_WORDDATA_ARG */ 108 case AML_DWORD_OP: /* AML_DWORDATA_ARG */ 109 case AML_QWORD_OP: /* AML_QWORDATA_ARG */ 110 case AML_STRING_OP: /* AML_ASCIICHARLIST_ARG */ 111 112 /* Fill in constant or string argument directly */ 113 114 AcpiPsGetNextSimpleArg (&(WalkState->ParserState), 115 GET_CURRENT_ARG_TYPE (WalkState->ArgTypes), Op); 116 break; 117 118 case AML_INT_NAMEPATH_OP: /* AML_NAMESTRING_ARG */ 119 120 Status = AcpiPsGetNextNamepath (WalkState, 121 &(WalkState->ParserState), Op, ACPI_POSSIBLE_METHOD_CALL); 122 if (ACPI_FAILURE (Status)) 123 { 124 return_ACPI_STATUS (Status); 125 } 126 127 WalkState->ArgTypes = 0; 128 break; 129 130 default: 131 /* 132 * Op is not a constant or string, append each argument to the Op 133 */ 134 while (GET_CURRENT_ARG_TYPE (WalkState->ArgTypes) && 135 !WalkState->ArgCount) 136 { 137 WalkState->Aml = WalkState->ParserState.Aml; 138 139 switch (Op->Common.AmlOpcode) 140 { 141 case AML_METHOD_OP: 142 case AML_BUFFER_OP: 143 case AML_PACKAGE_OP: 144 case AML_VARIABLE_PACKAGE_OP: 145 case AML_WHILE_OP: 146 147 break; 148 149 default: 150 151 ASL_CV_CAPTURE_COMMENTS (WalkState); 152 break; 153 } 154 155 Status = AcpiPsGetNextArg (WalkState, &(WalkState->ParserState), 156 GET_CURRENT_ARG_TYPE (WalkState->ArgTypes), &Arg); 157 if (ACPI_FAILURE (Status)) 158 { 159 return_ACPI_STATUS (Status); 160 } 161 162 if (Arg) 163 { 164 AcpiPsAppendArg (Op, Arg); 165 } 166 167 INCREMENT_ARG_LIST (WalkState->ArgTypes); 168 } 169 170 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, 171 "Final argument count: %8.8X pass %u\n", 172 WalkState->ArgCount, WalkState->PassNumber)); 173 174 /* Special processing for certain opcodes */ 175 176 switch (Op->Common.AmlOpcode) 177 { 178 case AML_METHOD_OP: 179 /* 180 * Skip parsing of control method because we don't have enough 181 * info in the first pass to parse it correctly. 182 * 183 * Save the length and address of the body 184 */ 185 Op->Named.Data = WalkState->ParserState.Aml; 186 Op->Named.Length = (UINT32) 187 (WalkState->ParserState.PkgEnd - WalkState->ParserState.Aml); 188 189 /* Skip body of method */ 190 191 WalkState->ParserState.Aml = WalkState->ParserState.PkgEnd; 192 WalkState->ArgCount = 0; 193 break; 194 195 case AML_BUFFER_OP: 196 case AML_PACKAGE_OP: 197 case AML_VARIABLE_PACKAGE_OP: 198 199 if ((Op->Common.Parent) && 200 (Op->Common.Parent->Common.AmlOpcode == AML_NAME_OP) && 201 (WalkState->PassNumber <= ACPI_IMODE_LOAD_PASS2)) 202 { 203 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, 204 "Setup Package/Buffer: Pass %u, AML Ptr: %p\n", 205 WalkState->PassNumber, AmlOpStart)); 206 207 /* 208 * Skip parsing of Buffers and Packages because we don't have 209 * enough info in the first pass to parse them correctly. 210 */ 211 Op->Named.Data = AmlOpStart; 212 Op->Named.Length = (UINT32) 213 (WalkState->ParserState.PkgEnd - AmlOpStart); 214 215 /* Skip body */ 216 217 WalkState->ParserState.Aml = WalkState->ParserState.PkgEnd; 218 WalkState->ArgCount = 0; 219 } 220 break; 221 222 case AML_WHILE_OP: 223 224 if (WalkState->ControlState) 225 { 226 WalkState->ControlState->Control.PackageEnd = 227 WalkState->ParserState.PkgEnd; 228 } 229 break; 230 231 default: 232 233 /* No action for all other opcodes */ 234 235 break; 236 } 237 238 break; 239 } 240 241 return_ACPI_STATUS (AE_OK); 242 } 243 244 245 /******************************************************************************* 246 * 247 * FUNCTION: AcpiPsParseLoop 248 * 249 * PARAMETERS: WalkState - Current state 250 * 251 * RETURN: Status 252 * 253 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return 254 * a tree of ops. 255 * 256 ******************************************************************************/ 257 258 ACPI_STATUS 259 AcpiPsParseLoop ( 260 ACPI_WALK_STATE *WalkState) 261 { 262 ACPI_STATUS Status = AE_OK; 263 ACPI_PARSE_OBJECT *Op = NULL; /* current op */ 264 ACPI_PARSE_STATE *ParserState; 265 UINT8 *AmlOpStart = NULL; 266 UINT8 OpcodeLength; 267 268 269 ACPI_FUNCTION_TRACE_PTR (PsParseLoop, WalkState); 270 271 272 if (WalkState->DescendingCallback == NULL) 273 { 274 return_ACPI_STATUS (AE_BAD_PARAMETER); 275 } 276 277 ParserState = &WalkState->ParserState; 278 WalkState->ArgTypes = 0; 279 280 #ifndef ACPI_CONSTANT_EVAL_ONLY 281 282 if (WalkState->WalkType & ACPI_WALK_METHOD_RESTART) 283 { 284 /* We are restarting a preempted control method */ 285 286 if (AcpiPsHasCompletedScope (ParserState)) 287 { 288 /* 289 * We must check if a predicate to an IF or WHILE statement 290 * was just completed 291 */ 292 if ((ParserState->Scope->ParseScope.Op) && 293 ((ParserState->Scope->ParseScope.Op->Common.AmlOpcode == AML_IF_OP) || 294 (ParserState->Scope->ParseScope.Op->Common.AmlOpcode == AML_WHILE_OP)) && 295 (WalkState->ControlState) && 296 (WalkState->ControlState->Common.State == 297 ACPI_CONTROL_PREDICATE_EXECUTING)) 298 { 299 /* 300 * A predicate was just completed, get the value of the 301 * predicate and branch based on that value 302 */ 303 WalkState->Op = NULL; 304 Status = AcpiDsGetPredicateValue (WalkState, ACPI_TO_POINTER (TRUE)); 305 if (ACPI_FAILURE (Status) && !ACPI_CNTL_EXCEPTION (Status)) 306 { 307 if (Status == AE_AML_NO_RETURN_VALUE) 308 { 309 ACPI_EXCEPTION ((AE_INFO, Status, 310 "Invoked method did not return a value")); 311 } 312 313 ACPI_EXCEPTION ((AE_INFO, Status, "GetPredicate Failed")); 314 return_ACPI_STATUS (Status); 315 } 316 317 Status = AcpiPsNextParseState (WalkState, Op, Status); 318 } 319 320 AcpiPsPopScope (ParserState, &Op, 321 &WalkState->ArgTypes, &WalkState->ArgCount); 322 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", Op)); 323 } 324 else if (WalkState->PrevOp) 325 { 326 /* We were in the middle of an op */ 327 328 Op = WalkState->PrevOp; 329 WalkState->ArgTypes = WalkState->PrevArgTypes; 330 } 331 } 332 #endif 333 334 /* Iterative parsing loop, while there is more AML to process: */ 335 336 while ((ParserState->Aml < ParserState->AmlEnd) || (Op)) 337 { 338 ASL_CV_CAPTURE_COMMENTS (WalkState); 339 340 AmlOpStart = ParserState->Aml; 341 if (!Op) 342 { 343 Status = AcpiPsCreateOp (WalkState, AmlOpStart, &Op); 344 if (ACPI_FAILURE (Status)) 345 { 346 /* 347 * ACPI_PARSE_MODULE_LEVEL means that we are loading a table by 348 * executing it as a control method. However, if we encounter 349 * an error while loading the table, we need to keep trying to 350 * load the table rather than aborting the table load. Set the 351 * status to AE_OK to proceed with the table load. 352 */ 353 if ((WalkState->ParseFlags & ACPI_PARSE_MODULE_LEVEL) && 354 ((Status == AE_ALREADY_EXISTS) || (Status == AE_NOT_FOUND))) 355 { 356 Status = AE_OK; 357 } 358 if (Status == AE_CTRL_PARSE_CONTINUE) 359 { 360 continue; 361 } 362 363 if (Status == AE_CTRL_PARSE_PENDING) 364 { 365 Status = AE_OK; 366 } 367 368 if (Status == AE_CTRL_TERMINATE) 369 { 370 return_ACPI_STATUS (Status); 371 } 372 373 Status = AcpiPsCompleteOp (WalkState, &Op, Status); 374 if (ACPI_FAILURE (Status)) 375 { 376 return_ACPI_STATUS (Status); 377 } 378 if (AcpiNsOpensScope ( 379 AcpiPsGetOpcodeInfo (WalkState->Opcode)->ObjectType)) 380 { 381 /* 382 * If the scope/device op fails to parse, skip the body of 383 * the scope op because the parse failure indicates that 384 * the device may not exist. 385 */ 386 ACPI_INFO (("Skipping parse of AML opcode: %s (0x%4.4X)", 387 AcpiPsGetOpcodeName (WalkState->Opcode), WalkState->Opcode)); 388 389 /* 390 * Determine the opcode length before skipping the opcode. 391 * An opcode can be 1 byte or 2 bytes in length. 392 */ 393 OpcodeLength = 1; 394 if ((WalkState->Opcode & 0xFF00) == AML_EXTENDED_OPCODE) 395 { 396 OpcodeLength = 2; 397 } 398 WalkState->ParserState.Aml = WalkState->Aml + OpcodeLength; 399 400 WalkState->ParserState.Aml = 401 AcpiPsGetNextPackageEnd(&WalkState->ParserState); 402 WalkState->Aml = WalkState->ParserState.Aml; 403 } 404 405 continue; 406 } 407 408 AcpiExStartTraceOpcode (Op, WalkState); 409 } 410 411 /* 412 * Start ArgCount at zero because we don't know if there are 413 * any args yet 414 */ 415 WalkState->ArgCount = 0; 416 417 switch (Op->Common.AmlOpcode) 418 { 419 case AML_BYTE_OP: 420 case AML_WORD_OP: 421 case AML_DWORD_OP: 422 case AML_QWORD_OP: 423 424 break; 425 426 default: 427 428 ASL_CV_CAPTURE_COMMENTS (WalkState); 429 break; 430 } 431 432 /* Are there any arguments that must be processed? */ 433 434 if (WalkState->ArgTypes) 435 { 436 /* Get arguments */ 437 438 Status = AcpiPsGetArguments (WalkState, AmlOpStart, Op); 439 if (ACPI_FAILURE (Status)) 440 { 441 Status = AcpiPsCompleteOp (WalkState, &Op, Status); 442 if (ACPI_FAILURE (Status)) 443 { 444 return_ACPI_STATUS (Status); 445 } 446 if ((WalkState->ControlState) && 447 ((WalkState->ControlState->Control.Opcode == AML_IF_OP) || 448 (WalkState->ControlState->Control.Opcode == AML_WHILE_OP))) 449 { 450 /* 451 * If the if/while op fails to parse, we will skip parsing 452 * the body of the op. 453 */ 454 ParserState->Aml = 455 WalkState->ControlState->Control.AmlPredicateStart + 1; 456 ParserState->Aml = 457 AcpiPsGetNextPackageEnd (ParserState); 458 WalkState->Aml = ParserState->Aml; 459 460 ACPI_ERROR ((AE_INFO, "Skipping While/If block")); 461 if (*WalkState->Aml == AML_ELSE_OP) 462 { 463 ACPI_ERROR ((AE_INFO, "Skipping Else block")); 464 WalkState->ParserState.Aml = WalkState->Aml + 1; 465 WalkState->ParserState.Aml = 466 AcpiPsGetNextPackageEnd (ParserState); 467 WalkState->Aml = ParserState->Aml; 468 } 469 ACPI_FREE(AcpiUtPopGenericState (&WalkState->ControlState)); 470 } 471 Op = NULL; 472 continue; 473 } 474 } 475 476 /* Check for arguments that need to be processed */ 477 478 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, 479 "Parseloop: argument count: %8.8X\n", WalkState->ArgCount)); 480 481 if (WalkState->ArgCount) 482 { 483 /* 484 * There are arguments (complex ones), push Op and 485 * prepare for argument 486 */ 487 Status = AcpiPsPushScope (ParserState, Op, 488 WalkState->ArgTypes, WalkState->ArgCount); 489 if (ACPI_FAILURE (Status)) 490 { 491 Status = AcpiPsCompleteOp (WalkState, &Op, Status); 492 if (ACPI_FAILURE (Status)) 493 { 494 return_ACPI_STATUS (Status); 495 } 496 497 continue; 498 } 499 500 Op = NULL; 501 continue; 502 } 503 504 /* 505 * All arguments have been processed -- Op is complete, 506 * prepare for next 507 */ 508 WalkState->OpInfo = AcpiPsGetOpcodeInfo (Op->Common.AmlOpcode); 509 if (WalkState->OpInfo->Flags & AML_NAMED) 510 { 511 if (Op->Common.AmlOpcode == AML_REGION_OP || 512 Op->Common.AmlOpcode == AML_DATA_REGION_OP) 513 { 514 /* 515 * Skip parsing of control method or opregion body, 516 * because we don't have enough info in the first pass 517 * to parse them correctly. 518 * 519 * Completed parsing an OpRegion declaration, we now 520 * know the length. 521 */ 522 Op->Named.Length = (UINT32) (ParserState->Aml - Op->Named.Data); 523 } 524 } 525 526 if (WalkState->OpInfo->Flags & AML_CREATE) 527 { 528 /* 529 * Backup to beginning of CreateXXXfield declaration (1 for 530 * Opcode) 531 * 532 * BodyLength is unknown until we parse the body 533 */ 534 Op->Named.Length = (UINT32) (ParserState->Aml - Op->Named.Data); 535 } 536 537 if (Op->Common.AmlOpcode == AML_BANK_FIELD_OP) 538 { 539 /* 540 * Backup to beginning of BankField declaration 541 * 542 * BodyLength is unknown until we parse the body 543 */ 544 Op->Named.Length = (UINT32) (ParserState->Aml - Op->Named.Data); 545 } 546 547 /* This op complete, notify the dispatcher */ 548 549 if (WalkState->AscendingCallback != NULL) 550 { 551 WalkState->Op = Op; 552 WalkState->Opcode = Op->Common.AmlOpcode; 553 554 Status = WalkState->AscendingCallback (WalkState); 555 Status = AcpiPsNextParseState (WalkState, Op, Status); 556 if (Status == AE_CTRL_PENDING) 557 { 558 Status = AE_OK; 559 } 560 else if ((WalkState->ParseFlags & ACPI_PARSE_MODULE_LEVEL) && 561 (ACPI_AML_EXCEPTION(Status) || Status == AE_ALREADY_EXISTS || 562 Status == AE_NOT_FOUND)) 563 { 564 /* 565 * ACPI_PARSE_MODULE_LEVEL flag means that we are currently 566 * loading a table by executing it as a control method. 567 * However, if we encounter an error while loading the table, 568 * we need to keep trying to load the table rather than 569 * aborting the table load (setting the status to AE_OK 570 * continues the table load). If we get a failure at this 571 * point, it means that the dispatcher got an error while 572 * trying to execute the Op. 573 */ 574 Status = AE_OK; 575 } 576 } 577 578 Status = AcpiPsCompleteOp (WalkState, &Op, Status); 579 if (ACPI_FAILURE (Status)) 580 { 581 return_ACPI_STATUS (Status); 582 } 583 584 } /* while ParserState->Aml */ 585 586 Status = AcpiPsCompleteFinalOp (WalkState, Op, Status); 587 return_ACPI_STATUS (Status); 588 } 589