1 /******************************************************************************* 2 * 3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace 4 * 5 ******************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2011, 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); 124 125 if (ACPI_FAILURE (Status) || (!NewNode)) /* Must be on same line for code converter */ 126 { 127 ACPI_EXCEPTION ((AE_INFO, Status, 128 "Could not create predefined name %s", 129 InitVal->Name)); 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 ObjDesc->Method.ParamCount = (UINT8) ACPI_TO_INTEGER (Val); 171 ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID; 172 173 #if defined (ACPI_ASL_COMPILER) 174 175 /* Save the parameter count for the iASL compiler */ 176 177 NewNode->Value = ObjDesc->Method.ParamCount; 178 #else 179 /* Mark this as a very SPECIAL method */ 180 181 ObjDesc->Method.InfoFlags = ACPI_METHOD_INTERNAL_ONLY; 182 ObjDesc->Method.Dispatch.Implementation = AcpiUtOsiImplementation; 183 #endif 184 break; 185 186 case ACPI_TYPE_INTEGER: 187 188 ObjDesc->Integer.Value = ACPI_TO_INTEGER (Val); 189 break; 190 191 192 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; 200 201 202 case ACPI_TYPE_MUTEX: 203 204 ObjDesc->Mutex.Node = NewNode; 205 ObjDesc->Mutex.SyncLevel = (UINT8) (ACPI_TO_INTEGER (Val) - 1); 206 207 /* Create a mutex */ 208 209 Status = AcpiOsCreateMutex (&ObjDesc->Mutex.OsMutex); 210 if (ACPI_FAILURE (Status)) 211 { 212 AcpiUtRemoveReference (ObjDesc); 213 goto UnlockAndExit; 214 } 215 216 /* Special case for ACPI Global Lock */ 217 218 if (ACPI_STRCMP (InitVal->Name, "_GL_") == 0) 219 { 220 AcpiGbl_GlobalLockMutex = ObjDesc; 221 222 /* Create additional counting semaphore for global lock */ 223 224 Status = AcpiOsCreateSemaphore ( 225 1, 0, &AcpiGbl_GlobalLockSemaphore); 226 if (ACPI_FAILURE (Status)) 227 { 228 AcpiUtRemoveReference (ObjDesc); 229 goto UnlockAndExit; 230 } 231 } 232 break; 233 234 235 default: 236 237 ACPI_ERROR ((AE_INFO, "Unsupported initial type value 0x%X", 238 InitVal->Type)); 239 AcpiUtRemoveReference (ObjDesc); 240 ObjDesc = NULL; 241 continue; 242 } 243 244 /* Store pointer to value descriptor in the Node */ 245 246 Status = AcpiNsAttachObject (NewNode, ObjDesc, 247 ObjDesc->Common.Type); 248 249 /* Remove local reference to the object */ 250 251 AcpiUtRemoveReference (ObjDesc); 252 } 253 } 254 255 256 UnlockAndExit: 257 (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE); 258 259 /* Save a handle to "_GPE", it is always present */ 260 261 if (ACPI_SUCCESS (Status)) 262 { 263 Status = AcpiNsGetNode (NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH, 264 &AcpiGbl_FadtGpeDevice); 265 } 266 267 return_ACPI_STATUS (Status); 268 } 269 270 271 /******************************************************************************* 272 * 273 * FUNCTION: AcpiNsLookup 274 * 275 * PARAMETERS: ScopeInfo - Current scope info block 276 * Pathname - Search pathname, in internal format 277 * (as represented in the AML stream) 278 * Type - Type associated with name 279 * InterpreterMode - IMODE_LOAD_PASS2 => add name if not found 280 * Flags - Flags describing the search restrictions 281 * WalkState - Current state of the walk 282 * ReturnNode - Where the Node is placed (if found 283 * or created successfully) 284 * 285 * RETURN: Status 286 * 287 * DESCRIPTION: Find or enter the passed name in the name space. 288 * Log an error if name not found in Exec mode. 289 * 290 * MUTEX: Assumes namespace is locked. 291 * 292 ******************************************************************************/ 293 294 ACPI_STATUS 295 AcpiNsLookup ( 296 ACPI_GENERIC_STATE *ScopeInfo, 297 char *Pathname, 298 ACPI_OBJECT_TYPE Type, 299 ACPI_INTERPRETER_MODE InterpreterMode, 300 UINT32 Flags, 301 ACPI_WALK_STATE *WalkState, 302 ACPI_NAMESPACE_NODE **ReturnNode) 303 { 304 ACPI_STATUS Status; 305 char *Path = Pathname; 306 ACPI_NAMESPACE_NODE *PrefixNode; 307 ACPI_NAMESPACE_NODE *CurrentNode = NULL; 308 ACPI_NAMESPACE_NODE *ThisNode = NULL; 309 UINT32 NumSegments; 310 UINT32 NumCarats; 311 ACPI_NAME SimpleName; 312 ACPI_OBJECT_TYPE TypeToCheckFor; 313 ACPI_OBJECT_TYPE ThisSearchType; 314 UINT32 SearchParentFlag = ACPI_NS_SEARCH_PARENT; 315 UINT32 LocalFlags; 316 317 318 ACPI_FUNCTION_TRACE (NsLookup); 319 320 321 if (!ReturnNode) 322 { 323 return_ACPI_STATUS (AE_BAD_PARAMETER); 324 } 325 326 LocalFlags = Flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT); 327 *ReturnNode = ACPI_ENTRY_NOT_FOUND; 328 AcpiGbl_NsLookupCount++; 329 330 if (!AcpiGbl_RootNode) 331 { 332 return_ACPI_STATUS (AE_NO_NAMESPACE); 333 } 334 335 /* Get the prefix scope. A null scope means use the root scope */ 336 337 if ((!ScopeInfo) || 338 (!ScopeInfo->Scope.Node)) 339 { 340 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 341 "Null scope prefix, using root node (%p)\n", 342 AcpiGbl_RootNode)); 343 344 PrefixNode = AcpiGbl_RootNode; 345 } 346 else 347 { 348 PrefixNode = ScopeInfo->Scope.Node; 349 if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED) 350 { 351 ACPI_ERROR ((AE_INFO, "%p is not a namespace node [%s]", 352 PrefixNode, AcpiUtGetDescriptorName (PrefixNode))); 353 return_ACPI_STATUS (AE_AML_INTERNAL); 354 } 355 356 if (!(Flags & ACPI_NS_PREFIX_IS_SCOPE)) 357 { 358 /* 359 * This node might not be a actual "scope" node (such as a 360 * Device/Method, etc.) It could be a Package or other object 361 * node. Backup up the tree to find the containing scope node. 362 */ 363 while (!AcpiNsOpensScope (PrefixNode->Type) && 364 PrefixNode->Type != ACPI_TYPE_ANY) 365 { 366 PrefixNode = PrefixNode->Parent; 367 } 368 } 369 } 370 371 /* Save type. TBD: may be no longer necessary */ 372 373 TypeToCheckFor = Type; 374 375 /* 376 * Begin examination of the actual pathname 377 */ 378 if (!Pathname) 379 { 380 /* A Null NamePath is allowed and refers to the root */ 381 382 NumSegments = 0; 383 ThisNode = AcpiGbl_RootNode; 384 Path = ""; 385 386 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 387 "Null Pathname (Zero segments), Flags=%X\n", Flags)); 388 } 389 else 390 { 391 /* 392 * Name pointer is valid (and must be in internal name format) 393 * 394 * Check for scope prefixes: 395 * 396 * As represented in the AML stream, a namepath consists of an 397 * optional scope prefix followed by a name segment part. 398 * 399 * If present, the scope prefix is either a Root Prefix (in 400 * which case the name is fully qualified), or one or more 401 * Parent Prefixes (in which case the name's scope is relative 402 * to the current scope). 403 */ 404 if (*Path == (UINT8) AML_ROOT_PREFIX) 405 { 406 /* Pathname is fully qualified, start from the root */ 407 408 ThisNode = AcpiGbl_RootNode; 409 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 410 411 /* Point to name segment part */ 412 413 Path++; 414 415 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 416 "Path is absolute from root [%p]\n", ThisNode)); 417 } 418 else 419 { 420 /* Pathname is relative to current scope, start there */ 421 422 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 423 "Searching relative to prefix scope [%4.4s] (%p)\n", 424 AcpiUtGetNodeName (PrefixNode), PrefixNode)); 425 426 /* 427 * Handle multiple Parent Prefixes (carat) by just getting 428 * the parent node for each prefix instance. 429 */ 430 ThisNode = PrefixNode; 431 NumCarats = 0; 432 while (*Path == (UINT8) AML_PARENT_PREFIX) 433 { 434 /* Name is fully qualified, no search rules apply */ 435 436 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 437 438 /* 439 * Point past this prefix to the name segment 440 * part or the next Parent Prefix 441 */ 442 Path++; 443 444 /* Backup to the parent node */ 445 446 NumCarats++; 447 ThisNode = ThisNode->Parent; 448 if (!ThisNode) 449 { 450 /* Current scope has no parent scope */ 451 452 ACPI_ERROR ((AE_INFO, 453 "ACPI path has too many parent prefixes (^) " 454 "- reached beyond root node")); 455 return_ACPI_STATUS (AE_NOT_FOUND); 456 } 457 } 458 459 if (SearchParentFlag == ACPI_NS_NO_UPSEARCH) 460 { 461 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 462 "Search scope is [%4.4s], path has %u carat(s)\n", 463 AcpiUtGetNodeName (ThisNode), NumCarats)); 464 } 465 } 466 467 /* 468 * Determine the number of ACPI name segments in this pathname. 469 * 470 * The segment part consists of either: 471 * - A Null name segment (0) 472 * - A DualNamePrefix followed by two 4-byte name segments 473 * - A MultiNamePrefix followed by a byte indicating the 474 * number of segments and the segments themselves. 475 * - A single 4-byte name segment 476 * 477 * Examine the name prefix opcode, if any, to determine the number of 478 * segments. 479 */ 480 switch (*Path) 481 { 482 case 0: 483 /* 484 * Null name after a root or parent prefixes. We already 485 * have the correct target node and there are no name segments. 486 */ 487 NumSegments = 0; 488 Type = ThisNode->Type; 489 490 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 491 "Prefix-only Pathname (Zero name segments), Flags=%X\n", 492 Flags)); 493 break; 494 495 case AML_DUAL_NAME_PREFIX: 496 497 /* More than one NameSeg, search rules do not apply */ 498 499 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 500 501 /* Two segments, point to first name segment */ 502 503 NumSegments = 2; 504 Path++; 505 506 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 507 "Dual Pathname (2 segments, Flags=%X)\n", Flags)); 508 break; 509 510 case AML_MULTI_NAME_PREFIX_OP: 511 512 /* More than one NameSeg, search rules do not apply */ 513 514 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 515 516 /* Extract segment count, point to first name segment */ 517 518 Path++; 519 NumSegments = (UINT32) (UINT8) *Path; 520 Path++; 521 522 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 523 "Multi Pathname (%u Segments, Flags=%X)\n", 524 NumSegments, Flags)); 525 break; 526 527 default: 528 /* 529 * Not a Null name, no Dual or Multi prefix, hence there is 530 * only one name segment and Pathname is already pointing to it. 531 */ 532 NumSegments = 1; 533 534 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 535 "Simple Pathname (1 segment, Flags=%X)\n", Flags)); 536 break; 537 } 538 539 ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path)); 540 } 541 542 543 /* 544 * Search namespace for each segment of the name. Loop through and 545 * verify (or add to the namespace) each name segment. 546 * 547 * The object type is significant only at the last name 548 * segment. (We don't care about the types along the path, only 549 * the type of the final target object.) 550 */ 551 ThisSearchType = ACPI_TYPE_ANY; 552 CurrentNode = ThisNode; 553 while (NumSegments && CurrentNode) 554 { 555 NumSegments--; 556 if (!NumSegments) 557 { 558 /* This is the last segment, enable typechecking */ 559 560 ThisSearchType = Type; 561 562 /* 563 * Only allow automatic parent search (search rules) if the caller 564 * requested it AND we have a single, non-fully-qualified NameSeg 565 */ 566 if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) && 567 (Flags & ACPI_NS_SEARCH_PARENT)) 568 { 569 LocalFlags |= ACPI_NS_SEARCH_PARENT; 570 } 571 572 /* Set error flag according to caller */ 573 574 if (Flags & ACPI_NS_ERROR_IF_FOUND) 575 { 576 LocalFlags |= ACPI_NS_ERROR_IF_FOUND; 577 } 578 } 579 580 /* Extract one ACPI name from the front of the pathname */ 581 582 ACPI_MOVE_32_TO_32 (&SimpleName, Path); 583 584 /* Try to find the single (4 character) ACPI name */ 585 586 Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode, 587 InterpreterMode, ThisSearchType, LocalFlags, &ThisNode); 588 if (ACPI_FAILURE (Status)) 589 { 590 if (Status == AE_NOT_FOUND) 591 { 592 /* Name not found in ACPI namespace */ 593 594 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 595 "Name [%4.4s] not found in scope [%4.4s] %p\n", 596 (char *) &SimpleName, (char *) &CurrentNode->Name, 597 CurrentNode)); 598 } 599 600 *ReturnNode = ThisNode; 601 return_ACPI_STATUS (Status); 602 } 603 604 /* More segments to follow? */ 605 606 if (NumSegments > 0) 607 { 608 /* 609 * If we have an alias to an object that opens a scope (such as a 610 * device or processor), we need to dereference the alias here so 611 * that we can access any children of the original node (via the 612 * remaining segments). 613 */ 614 if (ThisNode->Type == ACPI_TYPE_LOCAL_ALIAS) 615 { 616 if (!ThisNode->Object) 617 { 618 return_ACPI_STATUS (AE_NOT_EXIST); 619 } 620 621 if (AcpiNsOpensScope (((ACPI_NAMESPACE_NODE *) 622 ThisNode->Object)->Type)) 623 { 624 ThisNode = (ACPI_NAMESPACE_NODE *) ThisNode->Object; 625 } 626 } 627 } 628 629 /* Special handling for the last segment (NumSegments == 0) */ 630 631 else 632 { 633 /* 634 * Sanity typecheck of the target object: 635 * 636 * If 1) This is the last segment (NumSegments == 0) 637 * 2) And we are looking for a specific type 638 * (Not checking for TYPE_ANY) 639 * 3) Which is not an alias 640 * 4) Which is not a local type (TYPE_SCOPE) 641 * 5) And the type of target object is known (not TYPE_ANY) 642 * 6) And target object does not match what we are looking for 643 * 644 * Then we have a type mismatch. Just warn and ignore it. 645 */ 646 if ((TypeToCheckFor != ACPI_TYPE_ANY) && 647 (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS) && 648 (TypeToCheckFor != ACPI_TYPE_LOCAL_METHOD_ALIAS) && 649 (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE) && 650 (ThisNode->Type != ACPI_TYPE_ANY) && 651 (ThisNode->Type != TypeToCheckFor)) 652 { 653 /* Complain about a type mismatch */ 654 655 ACPI_WARNING ((AE_INFO, 656 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)", 657 ACPI_CAST_PTR (char, &SimpleName), 658 AcpiUtGetTypeName (ThisNode->Type), 659 AcpiUtGetTypeName (TypeToCheckFor))); 660 } 661 662 /* 663 * If this is the last name segment and we are not looking for a 664 * specific type, but the type of found object is known, use that 665 * type to (later) see if it opens a scope. 666 */ 667 if (Type == ACPI_TYPE_ANY) 668 { 669 Type = ThisNode->Type; 670 } 671 } 672 673 /* Point to next name segment and make this node current */ 674 675 Path += ACPI_NAME_SIZE; 676 CurrentNode = ThisNode; 677 } 678 679 /* Always check if we need to open a new scope */ 680 681 if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState)) 682 { 683 /* 684 * If entry is a type which opens a scope, push the new scope on the 685 * scope stack. 686 */ 687 if (AcpiNsOpensScope (Type)) 688 { 689 Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState); 690 if (ACPI_FAILURE (Status)) 691 { 692 return_ACPI_STATUS (Status); 693 } 694 } 695 } 696 697 *ReturnNode = ThisNode; 698 return_ACPI_STATUS (AE_OK); 699 } 700 701