1 /******************************************************************************* 2 * 3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace 4 * 5 ******************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2014, 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 #define __NSACCESS_C__ 45 46 #include "acpi.h" 47 #include "accommon.h" 48 #include "amlcode.h" 49 #include "acnamesp.h" 50 #include "acdispat.h" 51 52 53 #define _COMPONENT ACPI_NAMESPACE 54 ACPI_MODULE_NAME ("nsaccess") 55 56 57 /******************************************************************************* 58 * 59 * FUNCTION: AcpiNsRootInitialize 60 * 61 * PARAMETERS: None 62 * 63 * RETURN: Status 64 * 65 * DESCRIPTION: Allocate and initialize the default root named objects 66 * 67 * MUTEX: Locks namespace for entire execution 68 * 69 ******************************************************************************/ 70 71 ACPI_STATUS 72 AcpiNsRootInitialize ( 73 void) 74 { 75 ACPI_STATUS Status; 76 const ACPI_PREDEFINED_NAMES *InitVal = NULL; 77 ACPI_NAMESPACE_NODE *NewNode; 78 ACPI_OPERAND_OBJECT *ObjDesc; 79 ACPI_STRING Val = NULL; 80 81 82 ACPI_FUNCTION_TRACE (NsRootInitialize); 83 84 85 Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE); 86 if (ACPI_FAILURE (Status)) 87 { 88 return_ACPI_STATUS (Status); 89 } 90 91 /* 92 * The global root ptr is initially NULL, so a non-NULL value indicates 93 * that AcpiNsRootInitialize() has already been called; just return. 94 */ 95 if (AcpiGbl_RootNode) 96 { 97 Status = AE_OK; 98 goto UnlockAndExit; 99 } 100 101 /* 102 * Tell the rest of the subsystem that the root is initialized 103 * (This is OK because the namespace is locked) 104 */ 105 AcpiGbl_RootNode = &AcpiGbl_RootNodeStruct; 106 107 /* Enter the pre-defined names in the name table */ 108 109 ACPI_DEBUG_PRINT ((ACPI_DB_INFO, 110 "Entering predefined entries into namespace\n")); 111 112 for (InitVal = AcpiGbl_PreDefinedNames; InitVal->Name; InitVal++) 113 { 114 /* _OSI is optional for now, will be permanent later */ 115 116 if (!ACPI_STRCMP (InitVal->Name, "_OSI") && !AcpiGbl_CreateOsiMethod) 117 { 118 continue; 119 } 120 121 Status = AcpiNsLookup (NULL, InitVal->Name, InitVal->Type, 122 ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH, 123 NULL, &NewNode); 124 if (ACPI_FAILURE (Status)) 125 { 126 ACPI_EXCEPTION ((AE_INFO, Status, 127 "Could not create predefined name %s", 128 InitVal->Name)); 129 continue; 130 } 131 132 /* 133 * Name entered successfully. If entry in PreDefinedNames[] specifies 134 * an initial value, create the initial value. 135 */ 136 if (InitVal->Val) 137 { 138 Status = AcpiOsPredefinedOverride (InitVal, &Val); 139 if (ACPI_FAILURE (Status)) 140 { 141 ACPI_ERROR ((AE_INFO, 142 "Could not override predefined %s", 143 InitVal->Name)); 144 } 145 146 if (!Val) 147 { 148 Val = InitVal->Val; 149 } 150 151 /* 152 * Entry requests an initial value, allocate a 153 * descriptor for it. 154 */ 155 ObjDesc = AcpiUtCreateInternalObject (InitVal->Type); 156 if (!ObjDesc) 157 { 158 Status = AE_NO_MEMORY; 159 goto UnlockAndExit; 160 } 161 162 /* 163 * Convert value string from table entry to 164 * internal representation. Only types actually 165 * used for initial values are implemented here. 166 */ 167 switch (InitVal->Type) 168 { 169 case ACPI_TYPE_METHOD: 170 171 ObjDesc->Method.ParamCount = (UINT8) ACPI_TO_INTEGER (Val); 172 ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID; 173 174 #if defined (ACPI_ASL_COMPILER) 175 176 /* Save the parameter count for the iASL compiler */ 177 178 NewNode->Value = ObjDesc->Method.ParamCount; 179 #else 180 /* Mark this as a very SPECIAL method */ 181 182 ObjDesc->Method.InfoFlags = ACPI_METHOD_INTERNAL_ONLY; 183 ObjDesc->Method.Dispatch.Implementation = AcpiUtOsiImplementation; 184 #endif 185 break; 186 187 case ACPI_TYPE_INTEGER: 188 189 ObjDesc->Integer.Value = ACPI_TO_INTEGER (Val); 190 break; 191 192 case ACPI_TYPE_STRING: 193 194 /* Build an object around the static string */ 195 196 ObjDesc->String.Length = (UINT32) ACPI_STRLEN (Val); 197 ObjDesc->String.Pointer = Val; 198 ObjDesc->Common.Flags |= AOPOBJ_STATIC_POINTER; 199 break; 200 201 case ACPI_TYPE_MUTEX: 202 203 ObjDesc->Mutex.Node = NewNode; 204 ObjDesc->Mutex.SyncLevel = (UINT8) (ACPI_TO_INTEGER (Val) - 1); 205 206 /* Create a mutex */ 207 208 Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex); 209 if (ACPI_FAILURE (Status)) 210 { 211 AcpiUtRemoveReference (ObjDesc); 212 goto UnlockAndExit; 213 } 214 215 /* Special case for ACPI Global Lock */ 216 217 if (ACPI_STRCMP (InitVal->Name, "_GL_") == 0) 218 { 219 AcpiGbl_GlobalLockMutex = ObjDesc; 220 221 /* Create additional counting semaphore for global lock */ 222 223 Status = AcpiOsCreateSemaphore ( 224 1, 0, &AcpiGbl_GlobalLockSemaphore); 225 if (ACPI_FAILURE (Status)) 226 { 227 AcpiUtRemoveReference (ObjDesc); 228 goto UnlockAndExit; 229 } 230 } 231 break; 232 233 default: 234 235 ACPI_ERROR ((AE_INFO, "Unsupported initial type value 0x%X", 236 InitVal->Type)); 237 AcpiUtRemoveReference (ObjDesc); 238 ObjDesc = NULL; 239 continue; 240 } 241 242 /* Store pointer to value descriptor in the Node */ 243 244 Status = AcpiNsAttachObject (NewNode, ObjDesc, 245 ObjDesc->Common.Type); 246 247 /* Remove local reference to the object */ 248 249 AcpiUtRemoveReference (ObjDesc); 250 } 251 } 252 253 254 UnlockAndExit: 255 (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE); 256 257 /* Save a handle to "_GPE", it is always present */ 258 259 if (ACPI_SUCCESS (Status)) 260 { 261 Status = AcpiNsGetNode (NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH, 262 &AcpiGbl_FadtGpeDevice); 263 } 264 265 return_ACPI_STATUS (Status); 266 } 267 268 269 /******************************************************************************* 270 * 271 * FUNCTION: AcpiNsLookup 272 * 273 * PARAMETERS: ScopeInfo - Current scope info block 274 * Pathname - Search pathname, in internal format 275 * (as represented in the AML stream) 276 * Type - Type associated with name 277 * InterpreterMode - IMODE_LOAD_PASS2 => add name if not found 278 * Flags - Flags describing the search restrictions 279 * WalkState - Current state of the walk 280 * ReturnNode - Where the Node is placed (if found 281 * or created successfully) 282 * 283 * RETURN: Status 284 * 285 * DESCRIPTION: Find or enter the passed name in the name space. 286 * Log an error if name not found in Exec mode. 287 * 288 * MUTEX: Assumes namespace is locked. 289 * 290 ******************************************************************************/ 291 292 ACPI_STATUS 293 AcpiNsLookup ( 294 ACPI_GENERIC_STATE *ScopeInfo, 295 char *Pathname, 296 ACPI_OBJECT_TYPE Type, 297 ACPI_INTERPRETER_MODE InterpreterMode, 298 UINT32 Flags, 299 ACPI_WALK_STATE *WalkState, 300 ACPI_NAMESPACE_NODE **ReturnNode) 301 { 302 ACPI_STATUS Status; 303 char *Path = Pathname; 304 ACPI_NAMESPACE_NODE *PrefixNode; 305 ACPI_NAMESPACE_NODE *CurrentNode = NULL; 306 ACPI_NAMESPACE_NODE *ThisNode = NULL; 307 UINT32 NumSegments; 308 UINT32 NumCarats; 309 ACPI_NAME SimpleName; 310 ACPI_OBJECT_TYPE TypeToCheckFor; 311 ACPI_OBJECT_TYPE ThisSearchType; 312 UINT32 SearchParentFlag = ACPI_NS_SEARCH_PARENT; 313 UINT32 LocalFlags; 314 315 316 ACPI_FUNCTION_TRACE (NsLookup); 317 318 319 if (!ReturnNode) 320 { 321 return_ACPI_STATUS (AE_BAD_PARAMETER); 322 } 323 324 LocalFlags = Flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT); 325 *ReturnNode = ACPI_ENTRY_NOT_FOUND; 326 AcpiGbl_NsLookupCount++; 327 328 if (!AcpiGbl_RootNode) 329 { 330 return_ACPI_STATUS (AE_NO_NAMESPACE); 331 } 332 333 /* Get the prefix scope. A null scope means use the root scope */ 334 335 if ((!ScopeInfo) || 336 (!ScopeInfo->Scope.Node)) 337 { 338 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 339 "Null scope prefix, using root node (%p)\n", 340 AcpiGbl_RootNode)); 341 342 PrefixNode = AcpiGbl_RootNode; 343 } 344 else 345 { 346 PrefixNode = ScopeInfo->Scope.Node; 347 if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED) 348 { 349 ACPI_ERROR ((AE_INFO, "%p is not a namespace node [%s]", 350 PrefixNode, AcpiUtGetDescriptorName (PrefixNode))); 351 return_ACPI_STATUS (AE_AML_INTERNAL); 352 } 353 354 if (!(Flags & ACPI_NS_PREFIX_IS_SCOPE)) 355 { 356 /* 357 * This node might not be a actual "scope" node (such as a 358 * Device/Method, etc.) It could be a Package or other object 359 * node. Backup up the tree to find the containing scope node. 360 */ 361 while (!AcpiNsOpensScope (PrefixNode->Type) && 362 PrefixNode->Type != ACPI_TYPE_ANY) 363 { 364 PrefixNode = PrefixNode->Parent; 365 } 366 } 367 } 368 369 /* Save type. TBD: may be no longer necessary */ 370 371 TypeToCheckFor = Type; 372 373 /* 374 * Begin examination of the actual pathname 375 */ 376 if (!Pathname) 377 { 378 /* A Null NamePath is allowed and refers to the root */ 379 380 NumSegments = 0; 381 ThisNode = AcpiGbl_RootNode; 382 Path = ""; 383 384 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 385 "Null Pathname (Zero segments), Flags=%X\n", Flags)); 386 } 387 else 388 { 389 /* 390 * Name pointer is valid (and must be in internal name format) 391 * 392 * Check for scope prefixes: 393 * 394 * As represented in the AML stream, a namepath consists of an 395 * optional scope prefix followed by a name segment part. 396 * 397 * If present, the scope prefix is either a Root Prefix (in 398 * which case the name is fully qualified), or one or more 399 * Parent Prefixes (in which case the name's scope is relative 400 * to the current scope). 401 */ 402 if (*Path == (UINT8) AML_ROOT_PREFIX) 403 { 404 /* Pathname is fully qualified, start from the root */ 405 406 ThisNode = AcpiGbl_RootNode; 407 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 408 409 /* Point to name segment part */ 410 411 Path++; 412 413 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 414 "Path is absolute from root [%p]\n", ThisNode)); 415 } 416 else 417 { 418 /* Pathname is relative to current scope, start there */ 419 420 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 421 "Searching relative to prefix scope [%4.4s] (%p)\n", 422 AcpiUtGetNodeName (PrefixNode), PrefixNode)); 423 424 /* 425 * Handle multiple Parent Prefixes (carat) by just getting 426 * the parent node for each prefix instance. 427 */ 428 ThisNode = PrefixNode; 429 NumCarats = 0; 430 while (*Path == (UINT8) AML_PARENT_PREFIX) 431 { 432 /* Name is fully qualified, no search rules apply */ 433 434 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 435 436 /* 437 * Point past this prefix to the name segment 438 * part or the next Parent Prefix 439 */ 440 Path++; 441 442 /* Backup to the parent node */ 443 444 NumCarats++; 445 ThisNode = ThisNode->Parent; 446 if (!ThisNode) 447 { 448 /* Current scope has no parent scope */ 449 450 ACPI_ERROR ((AE_INFO, 451 "%s: Path has too many parent prefixes (^) " 452 "- reached beyond root node", Pathname)); 453 return_ACPI_STATUS (AE_NOT_FOUND); 454 } 455 } 456 457 if (SearchParentFlag == ACPI_NS_NO_UPSEARCH) 458 { 459 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 460 "Search scope is [%4.4s], path has %u carat(s)\n", 461 AcpiUtGetNodeName (ThisNode), NumCarats)); 462 } 463 } 464 465 /* 466 * Determine the number of ACPI name segments in this pathname. 467 * 468 * The segment part consists of either: 469 * - A Null name segment (0) 470 * - A DualNamePrefix followed by two 4-byte name segments 471 * - A MultiNamePrefix followed by a byte indicating the 472 * number of segments and the segments themselves. 473 * - A single 4-byte name segment 474 * 475 * Examine the name prefix opcode, if any, to determine the number of 476 * segments. 477 */ 478 switch (*Path) 479 { 480 case 0: 481 /* 482 * Null name after a root or parent prefixes. We already 483 * have the correct target node and there are no name segments. 484 */ 485 NumSegments = 0; 486 Type = ThisNode->Type; 487 488 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 489 "Prefix-only Pathname (Zero name segments), Flags=%X\n", 490 Flags)); 491 break; 492 493 case AML_DUAL_NAME_PREFIX: 494 495 /* More than one NameSeg, search rules do not apply */ 496 497 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 498 499 /* Two segments, point to first name segment */ 500 501 NumSegments = 2; 502 Path++; 503 504 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 505 "Dual Pathname (2 segments, Flags=%X)\n", Flags)); 506 break; 507 508 case AML_MULTI_NAME_PREFIX_OP: 509 510 /* More than one NameSeg, search rules do not apply */ 511 512 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 513 514 /* Extract segment count, point to first name segment */ 515 516 Path++; 517 NumSegments = (UINT32) (UINT8) *Path; 518 Path++; 519 520 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 521 "Multi Pathname (%u Segments, Flags=%X)\n", 522 NumSegments, Flags)); 523 break; 524 525 default: 526 /* 527 * Not a Null name, no Dual or Multi prefix, hence there is 528 * only one name segment and Pathname is already pointing to it. 529 */ 530 NumSegments = 1; 531 532 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 533 "Simple Pathname (1 segment, Flags=%X)\n", Flags)); 534 break; 535 } 536 537 ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path)); 538 } 539 540 541 /* 542 * Search namespace for each segment of the name. Loop through and 543 * verify (or add to the namespace) each name segment. 544 * 545 * The object type is significant only at the last name 546 * segment. (We don't care about the types along the path, only 547 * the type of the final target object.) 548 */ 549 ThisSearchType = ACPI_TYPE_ANY; 550 CurrentNode = ThisNode; 551 while (NumSegments && CurrentNode) 552 { 553 NumSegments--; 554 if (!NumSegments) 555 { 556 /* This is the last segment, enable typechecking */ 557 558 ThisSearchType = Type; 559 560 /* 561 * Only allow automatic parent search (search rules) if the caller 562 * requested it AND we have a single, non-fully-qualified NameSeg 563 */ 564 if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) && 565 (Flags & ACPI_NS_SEARCH_PARENT)) 566 { 567 LocalFlags |= ACPI_NS_SEARCH_PARENT; 568 } 569 570 /* Set error flag according to caller */ 571 572 if (Flags & ACPI_NS_ERROR_IF_FOUND) 573 { 574 LocalFlags |= ACPI_NS_ERROR_IF_FOUND; 575 } 576 } 577 578 /* Extract one ACPI name from the front of the pathname */ 579 580 ACPI_MOVE_32_TO_32 (&SimpleName, Path); 581 582 /* Try to find the single (4 character) ACPI name */ 583 584 Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode, 585 InterpreterMode, ThisSearchType, LocalFlags, &ThisNode); 586 if (ACPI_FAILURE (Status)) 587 { 588 if (Status == AE_NOT_FOUND) 589 { 590 /* Name not found in ACPI namespace */ 591 592 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 593 "Name [%4.4s] not found in scope [%4.4s] %p\n", 594 (char *) &SimpleName, (char *) &CurrentNode->Name, 595 CurrentNode)); 596 } 597 598 *ReturnNode = ThisNode; 599 return_ACPI_STATUS (Status); 600 } 601 602 /* More segments to follow? */ 603 604 if (NumSegments > 0) 605 { 606 /* 607 * If we have an alias to an object that opens a scope (such as a 608 * device or processor), we need to dereference the alias here so 609 * that we can access any children of the original node (via the 610 * remaining segments). 611 */ 612 if (ThisNode->Type == ACPI_TYPE_LOCAL_ALIAS) 613 { 614 if (!ThisNode->Object) 615 { 616 return_ACPI_STATUS (AE_NOT_EXIST); 617 } 618 619 if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE *) 620 ThisNode->Object)->Type)) 621 { 622 ThisNode = (ACPI_NAMESPACE_NODE *) ThisNode->Object; 623 } 624 } 625 } 626 627 /* Special handling for the last segment (NumSegments == 0) */ 628 629 else 630 { 631 /* 632 * Sanity typecheck of the target object: 633 * 634 * If 1) This is the last segment (NumSegments == 0) 635 * 2) And we are looking for a specific type 636 * (Not checking for TYPE_ANY) 637 * 3) Which is not an alias 638 * 4) Which is not a local type (TYPE_SCOPE) 639 * 5) And the type of target object is known (not TYPE_ANY) 640 * 6) And target object does not match what we are looking for 641 * 642 * Then we have a type mismatch. Just warn and ignore it. 643 */ 644 if ((TypeToCheckFor != ACPI_TYPE_ANY) && 645 (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS) && 646 (TypeToCheckFor != ACPI_TYPE_LOCAL_METHOD_ALIAS) && 647 (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE) && 648 (ThisNode->Type != ACPI_TYPE_ANY) && 649 (ThisNode->Type != TypeToCheckFor)) 650 { 651 /* Complain about a type mismatch */ 652 653 ACPI_WARNING ((AE_INFO, 654 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)", 655 ACPI_CAST_PTR (char, &SimpleName), 656 AcpiUtGetTypeName (ThisNode->Type), 657 AcpiUtGetTypeName (TypeToCheckFor))); 658 } 659 660 /* 661 * If this is the last name segment and we are not looking for a 662 * specific type, but the type of found object is known, use that 663 * type to (later) see if it opens a scope. 664 */ 665 if (Type == ACPI_TYPE_ANY) 666 { 667 Type = ThisNode->Type; 668 } 669 } 670 671 /* Point to next name segment and make this node current */ 672 673 Path += ACPI_NAME_SIZE; 674 CurrentNode = ThisNode; 675 } 676 677 /* Always check if we need to open a new scope */ 678 679 if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState)) 680 { 681 /* 682 * If entry is a type which opens a scope, push the new scope on the 683 * scope stack. 684 */ 685 if (AcpiNsOpensScope (Type)) 686 { 687 Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState); 688 if (ACPI_FAILURE (Status)) 689 { 690 return_ACPI_STATUS (Status); 691 } 692 } 693 } 694 695 *ReturnNode = ThisNode; 696 return_ACPI_STATUS (AE_OK); 697 }