nsaccess.c revision 107325
1189251Ssam/******************************************************************************* 2189251Ssam * 3189251Ssam * Module Name: nsaccess - Top-level functions for accessing ACPI namespace 4189251Ssam * $Revision: 165 $ 5252726Srpaulo * 6252726Srpaulo ******************************************************************************/ 7189251Ssam 8189251Ssam/****************************************************************************** 9189251Ssam * 10189251Ssam * 1. Copyright Notice 11189251Ssam * 12214734Srpaulo * Some or all of this work - Copyright (c) 1999 - 2002, Intel Corp. 13214734Srpaulo * All rights reserved. 14252726Srpaulo * 15189251Ssam * 2. License 16189251Ssam * 17189251Ssam * 2.1. This is your license from Intel Corp. under its intellectual property 18189251Ssam * rights. You may have additional license terms from the party that provided 19189251Ssam * you this software, covering your right to use that party's intellectual 20189251Ssam * property rights. 21189251Ssam * 22189251Ssam * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a 23189251Ssam * copy of the source code appearing in this file ("Covered Code") an 24189251Ssam * irrevocable, perpetual, worldwide license under Intel's copyrights in the 25189251Ssam * base code distributed originally by Intel ("Original Intel Code") to copy, 26189251Ssam * make derivatives, distribute, use and display any portion of the Covered 27189251Ssam * Code in any form, with the right to sublicense such rights; and 28189251Ssam * 29189251Ssam * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent 30189251Ssam * license (with the right to sublicense), under only those claims of Intel 31189251Ssam * patents that are infringed by the Original Intel Code, to make, use, sell, 32189251Ssam * offer to sell, and import the Covered Code and derivative works thereof 33189251Ssam * solely to the minimum extent necessary to exercise the above copyright 34189251Ssam * license, and in no event shall the patent license extend to any additions 35189251Ssam * to or modifications of the Original Intel Code. No other license or right 36189251Ssam * is granted directly or by implication, estoppel or otherwise; 37189251Ssam * 38189251Ssam * The above copyright and patent license is granted only if the following 39189251Ssam * conditions are met: 40189251Ssam * 41189251Ssam * 3. Conditions 42189251Ssam * 43189251Ssam * 3.1. Redistribution of Source with Rights to Further Distribute Source. 44189251Ssam * Redistribution of source code of any substantial portion of the Covered 45189251Ssam * Code or modification with rights to further distribute source must include 46189251Ssam * the above Copyright Notice, the above License, this list of Conditions, 47189251Ssam * and the following Disclaimer and Export Compliance provision. In addition, 48189251Ssam * Licensee must cause all Covered Code to which Licensee contributes to 49189251Ssam * contain a file documenting the changes Licensee made to create that Covered 50189251Ssam * Code and the date of any change. Licensee must include in that file the 51189251Ssam * documentation of any changes made by any predecessor Licensee. Licensee 52189251Ssam * must include a prominent statement that the modification is derived, 53189251Ssam * directly or indirectly, from Original Intel Code. 54189251Ssam * 55189251Ssam * 3.2. Redistribution of Source with no Rights to Further Distribute Source. 56189251Ssam * Redistribution of source code of any substantial portion of the Covered 57189251Ssam * Code or modification without rights to further distribute source must 58189251Ssam * include the following Disclaimer and Export Compliance provision in the 59189251Ssam * documentation and/or other materials provided with distribution. In 60189251Ssam * addition, Licensee may not authorize further sublicense of source of any 61189251Ssam * portion of the Covered Code, and must include terms to the effect that the 62189251Ssam * license from Licensee to its licensee is limited to the intellectual 63189251Ssam * property embodied in the software Licensee provides to its licensee, and 64189251Ssam * not to intellectual property embodied in modifications its licensee may 65189251Ssam * make. 66189251Ssam * 67189251Ssam * 3.3. Redistribution of Executable. Redistribution in executable form of any 68189251Ssam * substantial portion of the Covered Code or modification must reproduce the 69189251Ssam * above Copyright Notice, and the following Disclaimer and Export Compliance 70189251Ssam * provision in the documentation and/or other materials provided with the 71189251Ssam * distribution. 72189251Ssam * 73189251Ssam * 3.4. Intel retains all right, title, and interest in and to the Original 74189251Ssam * Intel Code. 75189251Ssam * 76189251Ssam * 3.5. Neither the name Intel nor any other trademark owned or controlled by 77189251Ssam * Intel shall be used in advertising or otherwise to promote the sale, use or 78189251Ssam * other dealings in products derived from or relating to the Covered Code 79189251Ssam * without prior written authorization from Intel. 80189251Ssam * 81189251Ssam * 4. Disclaimer and Export Compliance 82189251Ssam * 83189251Ssam * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED 84189251Ssam * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE 85189251Ssam * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, 86189251Ssam * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY 87189251Ssam * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY 88189251Ssam * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A 89189251Ssam * PARTICULAR PURPOSE. 90189251Ssam * 91189251Ssam * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES 92189251Ssam * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR 93189251Ssam * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, 94189251Ssam * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY 95189251Ssam * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL 96189251Ssam * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS 97189251Ssam * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY 98189251Ssam * LIMITED REMEDY. 99189251Ssam * 100189251Ssam * 4.3. Licensee shall not export, either directly or indirectly, any of this 101189251Ssam * software or system incorporating such software without first obtaining any 102189251Ssam * required license or other approval from the U. S. Department of Commerce or 103189251Ssam * any other agency or department of the United States Government. In the 104189251Ssam * event Licensee exports any such software from the United States or 105189251Ssam * re-exports any such software from a foreign destination, Licensee shall 106189251Ssam * ensure that the distribution and export/re-export of the software is in 107189251Ssam * compliance with all laws, regulations, orders, or other restrictions of the 108189251Ssam * U.S. Export Administration Regulations. Licensee agrees that neither it nor 109189251Ssam * any of its subsidiaries will export/re-export any technical data, process, 110189251Ssam * software, or service, directly or indirectly, to any country for which the 111189251Ssam * United States government or any agency thereof requires an export license, 112189251Ssam * other governmental approval, or letter of assurance, without first obtaining 113189251Ssam * such license, approval or letter. 114189251Ssam * 115189251Ssam *****************************************************************************/ 116189251Ssam 117189251Ssam#define __NSACCESS_C__ 118346981Scy 119346981Scy#include "acpi.h" 120346981Scy#include "amlcode.h" 121346981Scy#include "acnamesp.h" 122346981Scy#include "acdispat.h" 123346981Scy 124346981Scy 125346981Scy#define _COMPONENT ACPI_NAMESPACE 126189251Ssam ACPI_MODULE_NAME ("nsaccess") 127189251Ssam 128189251Ssam 129189251Ssam/******************************************************************************* 130189251Ssam * 131189251Ssam * FUNCTION: AcpiNsRootInitialize 132189251Ssam * 133189251Ssam * PARAMETERS: None 134189251Ssam * 135189251Ssam * RETURN: Status 136189251Ssam * 137189251Ssam * DESCRIPTION: Allocate and initialize the default root named objects 138189251Ssam * 139189251Ssam * MUTEX: Locks namespace for entire execution 140189251Ssam * 141189251Ssam ******************************************************************************/ 142189251Ssam 143189251SsamACPI_STATUS 144189251SsamAcpiNsRootInitialize (void) 145189251Ssam{ 146189251Ssam ACPI_STATUS Status; 147189251Ssam const ACPI_PREDEFINED_NAMES *InitVal = NULL; 148189251Ssam ACPI_NAMESPACE_NODE *NewNode; 149189251Ssam ACPI_OPERAND_OBJECT *ObjDesc; 150189251Ssam 151189251Ssam 152189251Ssam ACPI_FUNCTION_TRACE ("NsRootInitialize"); 153189251Ssam 154189251Ssam 155189251Ssam Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE); 156189251Ssam if (ACPI_FAILURE (Status)) 157189251Ssam { 158189251Ssam return_ACPI_STATUS (Status); 159189251Ssam } 160189251Ssam 161189251Ssam /* 162189251Ssam * The global root ptr is initially NULL, so a non-NULL value indicates 163189251Ssam * that AcpiNsRootInitialize() has already been called; just return. 164189251Ssam */ 165189251Ssam if (AcpiGbl_RootNode) 166189251Ssam { 167189251Ssam Status = AE_OK; 168189251Ssam goto UnlockAndExit; 169252726Srpaulo } 170189251Ssam 171189251Ssam /* 172189251Ssam * Tell the rest of the subsystem that the root is initialized 173189251Ssam * (This is OK because the namespace is locked) 174189251Ssam */ 175189251Ssam AcpiGbl_RootNode = &AcpiGbl_RootNodeStruct; 176189251Ssam 177189251Ssam /* Enter the pre-defined names in the name table */ 178189251Ssam 179189251Ssam ACPI_DEBUG_PRINT ((ACPI_DB_INFO, 180189251Ssam "Entering predefined entries into namespace\n")); 181189251Ssam 182189251Ssam for (InitVal = AcpiGbl_PreDefinedNames; InitVal->Name; InitVal++) 183189251Ssam { 184189251Ssam Status = AcpiNsLookup (NULL, InitVal->Name, InitVal->Type, 185189251Ssam ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH, NULL, &NewNode); 186189251Ssam 187189251Ssam if (ACPI_FAILURE (Status) || (!NewNode)) /* Must be on same line for code converter */ 188189251Ssam { 189189251Ssam ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, 190189251Ssam "Could not create predefined name %s, %s\n", 191189251Ssam InitVal->Name, AcpiFormatException (Status))); 192189251Ssam } 193189251Ssam 194189251Ssam /* 195189251Ssam * Name entered successfully. 196189251Ssam * If entry in PreDefinedNames[] specifies an 197189251Ssam * initial value, create the initial value. 198189251Ssam */ 199189251Ssam if (InitVal->Val) 200189251Ssam { 201189251Ssam /* 202189251Ssam * Entry requests an initial value, allocate a 203189251Ssam * descriptor for it. 204189251Ssam */ 205189251Ssam ObjDesc = AcpiUtCreateInternalObject (InitVal->Type); 206189251Ssam if (!ObjDesc) 207189251Ssam { 208189251Ssam Status = AE_NO_MEMORY; 209189251Ssam goto UnlockAndExit; 210189251Ssam } 211189251Ssam 212189251Ssam /* 213189251Ssam * Convert value string from table entry to 214189251Ssam * internal representation. Only types actually 215189251Ssam * used for initial values are implemented here. 216189251Ssam */ 217189251Ssam switch (InitVal->Type) 218189251Ssam { 219189251Ssam case ACPI_TYPE_METHOD: 220189251Ssam ObjDesc->Method.ParamCount = 221189251Ssam (UINT8) ACPI_STRTOUL (InitVal->Val, NULL, 10); 222189251Ssam ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID; 223189251Ssam 224189251Ssam#if defined (ACPI_NO_METHOD_EXECUTION) || defined (ACPI_CONSTANT_EVAL_ONLY) 225189251Ssam 226189251Ssam /* Compiler cheats by putting parameter count in the OwnerID */ 227189251Ssam 228189251Ssam NewNode->OwnerId = ObjDesc->Method.ParamCount; 229189251Ssam#endif 230189251Ssam break; 231189251Ssam 232189251Ssam case ACPI_TYPE_INTEGER: 233189251Ssam 234189251Ssam ObjDesc->Integer.Value = 235214734Srpaulo (ACPI_INTEGER) ACPI_STRTOUL (InitVal->Val, NULL, 10); 236214734Srpaulo break; 237214734Srpaulo 238214734Srpaulo 239189251Ssam case ACPI_TYPE_STRING: 240214734Srpaulo 241214734Srpaulo /* 242214734Srpaulo * Build an object around the static string 243214734Srpaulo */ 244214734Srpaulo ObjDesc->String.Length = (UINT32) ACPI_STRLEN (InitVal->Val); 245189251Ssam ObjDesc->String.Pointer = InitVal->Val; 246346981Scy ObjDesc->Common.Flags |= AOPOBJ_STATIC_POINTER; 247346981Scy break; 248346981Scy 249346981Scy 250189251Ssam case ACPI_TYPE_MUTEX: 251189251Ssam 252189251Ssam ObjDesc->Mutex.Node = NewNode; 253189251Ssam ObjDesc->Mutex.SyncLevel = 254281806Srpaulo (UINT16) ACPI_STRTOUL (InitVal->Val, NULL, 10); 255189251Ssam 256189251Ssam if (ACPI_STRCMP (InitVal->Name, "_GL_") == 0) 257189251Ssam { 258189251Ssam /* 259189251Ssam * Create a counting semaphore for the 260189251Ssam * global lock 261189251Ssam */ 262189251Ssam Status = AcpiOsCreateSemaphore (ACPI_NO_UNIT_LIMIT, 263189251Ssam 1, &ObjDesc->Mutex.Semaphore); 264189251Ssam if (ACPI_FAILURE (Status)) 265189251Ssam { 266189251Ssam goto UnlockAndExit; 267189251Ssam } 268189251Ssam 269189251Ssam /* 270189251Ssam * We just created the mutex for the 271189251Ssam * global lock, save it 272189251Ssam */ 273189251Ssam AcpiGbl_GlobalLockSemaphore = ObjDesc->Mutex.Semaphore; 274189251Ssam } 275189251Ssam else 276189251Ssam { 277189251Ssam /* Create a mutex */ 278189251Ssam 279189251Ssam Status = AcpiOsCreateSemaphore (1, 1, 280189251Ssam &ObjDesc->Mutex.Semaphore); 281189251Ssam if (ACPI_FAILURE (Status)) 282189251Ssam { 283189251Ssam goto UnlockAndExit; 284189251Ssam } 285189251Ssam } 286189251Ssam break; 287189251Ssam 288189251Ssam 289189251Ssam default: 290189251Ssam ACPI_REPORT_ERROR (("Unsupported initial type value %X\n", 291189251Ssam InitVal->Type)); 292189251Ssam AcpiUtRemoveReference (ObjDesc); 293189251Ssam ObjDesc = NULL; 294189251Ssam continue; 295189251Ssam } 296189251Ssam 297189251Ssam /* Store pointer to value descriptor in the Node */ 298189251Ssam 299189251Ssam Status = AcpiNsAttachObject (NewNode, ObjDesc, ACPI_GET_OBJECT_TYPE (ObjDesc)); 300189251Ssam 301189251Ssam /* Remove local reference to the object */ 302189251Ssam 303189251Ssam AcpiUtRemoveReference (ObjDesc); 304189251Ssam } 305189251Ssam } 306189251Ssam 307189251Ssam 308189251SsamUnlockAndExit: 309189251Ssam (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE); 310189251Ssam return_ACPI_STATUS (Status); 311189251Ssam} 312189251Ssam 313189251Ssam 314189251Ssam/******************************************************************************* 315189251Ssam * 316189251Ssam * FUNCTION: AcpiNsLookup 317189251Ssam * 318189251Ssam * PARAMETERS: PrefixNode - Search scope if name is not fully qualified 319189251Ssam * Pathname - Search pathname, in internal format 320189251Ssam * (as represented in the AML stream) 321189251Ssam * Type - Type associated with name 322189251Ssam * InterpreterMode - IMODE_LOAD_PASS2 => add name if not found 323189251Ssam * Flags - Flags describing the search restrictions 324189251Ssam * WalkState - Current state of the walk 325189251Ssam * ReturnNode - Where the Node is placed (if found 326189251Ssam * or created successfully) 327189251Ssam * 328189251Ssam * RETURN: Status 329189251Ssam * 330189251Ssam * DESCRIPTION: Find or enter the passed name in the name space. 331189251Ssam * Log an error if name not found in Exec mode. 332189251Ssam * 333189251Ssam * MUTEX: Assumes namespace is locked. 334189251Ssam * 335189251Ssam ******************************************************************************/ 336189251Ssam 337189251SsamACPI_STATUS 338189251SsamAcpiNsLookup ( 339189251Ssam ACPI_GENERIC_STATE *ScopeInfo, 340189251Ssam NATIVE_CHAR *Pathname, 341189251Ssam ACPI_OBJECT_TYPE Type, 342189251Ssam ACPI_INTERPRETER_MODE InterpreterMode, 343189251Ssam UINT32 Flags, 344189251Ssam ACPI_WALK_STATE *WalkState, 345189251Ssam ACPI_NAMESPACE_NODE **ReturnNode) 346189251Ssam{ 347189251Ssam ACPI_STATUS Status; 348189251Ssam NATIVE_CHAR *Path = Pathname; 349189251Ssam ACPI_NAMESPACE_NODE *PrefixNode; 350189251Ssam ACPI_NAMESPACE_NODE *CurrentNode = NULL; 351189251Ssam ACPI_NAMESPACE_NODE *ThisNode = NULL; 352189251Ssam UINT32 NumSegments; 353189251Ssam UINT32 NumCarats; 354189251Ssam ACPI_NAME SimpleName; 355189251Ssam ACPI_OBJECT_TYPE TypeToCheckFor; 356214734Srpaulo ACPI_OBJECT_TYPE ThisSearchType; 357214734Srpaulo UINT32 SearchParentFlag = ACPI_NS_SEARCH_PARENT; 358214734Srpaulo UINT32 LocalFlags = Flags & ~(ACPI_NS_ERROR_IF_FOUND | 359214734Srpaulo ACPI_NS_SEARCH_PARENT); 360214734Srpaulo 361214734Srpaulo 362214734Srpaulo ACPI_FUNCTION_TRACE ("NsLookup"); 363214734Srpaulo 364214734Srpaulo 365214734Srpaulo if (!ReturnNode) 366214734Srpaulo { 367189251Ssam return_ACPI_STATUS (AE_BAD_PARAMETER); 368189251Ssam } 369189251Ssam 370189251Ssam AcpiGbl_NsLookupCount++; 371189251Ssam *ReturnNode = ACPI_ENTRY_NOT_FOUND; 372189251Ssam 373189251Ssam if (!AcpiGbl_RootNode) 374189251Ssam { 375189251Ssam return_ACPI_STATUS (AE_NO_NAMESPACE); 376189251Ssam } 377189251Ssam 378189251Ssam /* 379189251Ssam * Get the prefix scope. 380189251Ssam * A null scope means use the root scope 381189251Ssam */ 382189251Ssam if ((!ScopeInfo) || 383189251Ssam (!ScopeInfo->Scope.Node)) 384189251Ssam { 385189251Ssam ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 386189251Ssam "Null scope prefix, using root node (%p)\n", 387189251Ssam AcpiGbl_RootNode)); 388189251Ssam 389189251Ssam PrefixNode = AcpiGbl_RootNode; 390189251Ssam } 391189251Ssam else 392189251Ssam { 393351611Scy PrefixNode = ScopeInfo->Scope.Node; 394351611Scy if (ACPI_GET_DESCRIPTOR_TYPE (PrefixNode) != ACPI_DESC_TYPE_NAMED) 395281806Srpaulo { 396189251Ssam ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "[%p] Not a namespace node\n", 397189251Ssam PrefixNode)); 398189251Ssam return_ACPI_STATUS (AE_AML_INTERNAL); 399189251Ssam } 400189251Ssam 401189251Ssam /* 402189251Ssam * This node might not be a actual "scope" node (such as a 403189251Ssam * Device/Method, etc.) It could be a Package or other object node. 404189251Ssam * Backup up the tree to find the containing scope node. 405189251Ssam */ 406189251Ssam while (!AcpiNsOpensScope (PrefixNode->Type) && 407189251Ssam PrefixNode->Type != ACPI_TYPE_ANY) 408189251Ssam { 409189251Ssam PrefixNode = AcpiNsGetParentNode (PrefixNode); 410189251Ssam } 411189251Ssam } 412189251Ssam 413189251Ssam /* Save type TBD: may be no longer necessary */ 414189251Ssam 415337817Scy TypeToCheckFor = Type; 416189251Ssam 417 /* 418 * Begin examination of the actual pathname 419 */ 420 if (!Pathname) 421 { 422 /* A Null NamePath is allowed and refers to the root */ 423 424 NumSegments = 0; 425 ThisNode = AcpiGbl_RootNode; 426 Path = ""; 427 428 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 429 "Null Pathname (Zero segments), Flags=%X\n", Flags)); 430 } 431 else 432 { 433 /* 434 * Name pointer is valid (and must be in internal name format) 435 * 436 * Check for scope prefixes: 437 * 438 * As represented in the AML stream, a namepath consists of an 439 * optional scope prefix followed by a name segment part. 440 * 441 * If present, the scope prefix is either a Root Prefix (in 442 * which case the name is fully qualified), or one or more 443 * Parent Prefixes (in which case the name's scope is relative 444 * to the current scope). 445 */ 446 if (*Path == (UINT8) AML_ROOT_PREFIX) 447 { 448 /* Pathname is fully qualified, start from the root */ 449 450 ThisNode = AcpiGbl_RootNode; 451 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 452 453 /* Point to name segment part */ 454 455 Path++; 456 457 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 458 "Path is absolute from root [%p]\n", ThisNode)); 459 } 460 else 461 { 462 /* Pathname is relative to current scope, start there */ 463 464 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 465 "Searching relative to prefix scope [%4.4s] (%p)\n", 466 PrefixNode->Name.Ascii, PrefixNode)); 467 468 /* 469 * Handle multiple Parent Prefixes (carat) by just getting 470 * the parent node for each prefix instance. 471 */ 472 ThisNode = PrefixNode; 473 NumCarats = 0; 474 while (*Path == (UINT8) AML_PARENT_PREFIX) 475 { 476 /* Name is fully qualified, no search rules apply */ 477 478 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 479 /* 480 * Point past this prefix to the name segment 481 * part or the next Parent Prefix 482 */ 483 Path++; 484 485 /* Backup to the parent node */ 486 487 NumCarats++; 488 ThisNode = AcpiNsGetParentNode (ThisNode); 489 if (!ThisNode) 490 { 491 /* Current scope has no parent scope */ 492 493 ACPI_REPORT_ERROR ( 494 ("ACPI path has too many parent prefixes (^) - reached beyond root node\n")); 495 return_ACPI_STATUS (AE_NOT_FOUND); 496 } 497 } 498 499 if (SearchParentFlag == ACPI_NS_NO_UPSEARCH) 500 { 501 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 502 "Search scope is [%4.4s], path has %d carat(s)\n", 503 ThisNode->Name.Ascii, NumCarats)); 504 } 505 } 506 507 /* 508 * Determine the number of ACPI name segments in this pathname. 509 * 510 * The segment part consists of either: 511 * - A Null name segment (0) 512 * - A DualNamePrefix followed by two 4-byte name segments 513 * - A MultiNamePrefix followed by a byte indicating the 514 * number of segments and the segments themselves. 515 * - A single 4-byte name segment 516 * 517 * Examine the name prefix opcode, if any, to determine the number of 518 * segments. 519 */ 520 switch (*Path) 521 { 522 case 0: 523 /* 524 * Null name after a root or parent prefixes. We already 525 * have the correct target node and there are no name segments. 526 */ 527 NumSegments = 0; 528 Type = ThisNode->Type; 529 530 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 531 "Prefix-only Pathname (Zero name segments), Flags=%X\n", Flags)); 532 break; 533 534 case AML_DUAL_NAME_PREFIX: 535 536 /* More than one NameSeg, search rules do not apply */ 537 538 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 539 540 /* Two segments, point to first name segment */ 541 542 NumSegments = 2; 543 Path++; 544 545 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 546 "Dual Pathname (2 segments, Flags=%X)\n", Flags)); 547 break; 548 549 case AML_MULTI_NAME_PREFIX_OP: 550 551 /* More than one NameSeg, search rules do not apply */ 552 553 SearchParentFlag = ACPI_NS_NO_UPSEARCH; 554 555 /* Extract segment count, point to first name segment */ 556 557 Path++; 558 NumSegments = (UINT32) (UINT8) *Path; 559 Path++; 560 561 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 562 "Multi Pathname (%d Segments, Flags=%X) \n", 563 NumSegments, Flags)); 564 break; 565 566 default: 567 /* 568 * Not a Null name, no Dual or Multi prefix, hence there is 569 * only one name segment and Pathname is already pointing to it. 570 */ 571 NumSegments = 1; 572 573 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 574 "Simple Pathname (1 segment, Flags=%X)\n", Flags)); 575 break; 576 } 577 578 ACPI_DEBUG_EXEC (AcpiNsPrintPathname (NumSegments, Path)); 579 } 580 581 582 /* 583 * Search namespace for each segment of the name. Loop through and 584 * verify (or add to the namespace) each name segment. 585 * 586 * The object type is significant only at the last name 587 * segment. (We don't care about the types along the path, only 588 * the type of the final target object.) 589 */ 590 ThisSearchType = ACPI_TYPE_ANY; 591 CurrentNode = ThisNode; 592 while (NumSegments && CurrentNode) 593 { 594 NumSegments--; 595 if (!NumSegments) 596 { 597 /* 598 * This is the last segment, enable typechecking 599 */ 600 ThisSearchType = Type; 601 602 /* 603 * Only allow automatic parent search (search rules) if the caller 604 * requested it AND we have a single, non-fully-qualified NameSeg 605 */ 606 if ((SearchParentFlag != ACPI_NS_NO_UPSEARCH) && 607 (Flags & ACPI_NS_SEARCH_PARENT)) 608 { 609 LocalFlags |= ACPI_NS_SEARCH_PARENT; 610 } 611 612 /* Set error flag according to caller */ 613 614 if (Flags & ACPI_NS_ERROR_IF_FOUND) 615 { 616 LocalFlags |= ACPI_NS_ERROR_IF_FOUND; 617 } 618 } 619 620 /* Extract one ACPI name from the front of the pathname */ 621 622 ACPI_MOVE_UNALIGNED32_TO_32 (&SimpleName, Path); 623 624 /* Try to find the single (4 character) ACPI name */ 625 626 Status = AcpiNsSearchAndEnter (SimpleName, WalkState, CurrentNode, 627 InterpreterMode, ThisSearchType, LocalFlags, &ThisNode); 628 if (ACPI_FAILURE (Status)) 629 { 630 if (Status == AE_NOT_FOUND) 631 { 632 /* Name not found in ACPI namespace */ 633 634 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 635 "Name [%4.4s] not found in scope [%4.4s] %p\n", 636 (char *) &SimpleName, (char *) &CurrentNode->Name, 637 CurrentNode)); 638 } 639 640 *ReturnNode = ThisNode; 641 return_ACPI_STATUS (Status); 642 } 643 644 /* 645 * Sanity typecheck of the target object: 646 * 647 * If 1) This is the last segment (NumSegments == 0) 648 * 2) And we are looking for a specific type 649 * (Not checking for TYPE_ANY) 650 * 3) Which is not an alias 651 * 4) Which is not a local type (TYPE_SCOPE) 652 * 5) And the type of target object is known (not TYPE_ANY) 653 * 6) And target object does not match what we are looking for 654 * 655 * Then we have a type mismatch. Just warn and ignore it. 656 */ 657 if ((NumSegments == 0) && 658 (TypeToCheckFor != ACPI_TYPE_ANY) && 659 (TypeToCheckFor != ACPI_TYPE_LOCAL_ALIAS) && 660 (TypeToCheckFor != ACPI_TYPE_LOCAL_SCOPE) && 661 (ThisNode->Type != ACPI_TYPE_ANY) && 662 (ThisNode->Type != TypeToCheckFor)) 663 { 664 /* Complain about a type mismatch */ 665 666 ACPI_REPORT_WARNING ( 667 ("NsLookup: Type mismatch on %4.4s (%s), searching for (%s)\n", 668 (char *) &SimpleName, AcpiUtGetTypeName (ThisNode->Type), 669 AcpiUtGetTypeName (TypeToCheckFor))); 670 } 671 672 /* 673 * If this is the last name segment and we are not looking for a 674 * specific type, but the type of found object is known, use that type 675 * to see if it opens a scope. 676 */ 677 if ((NumSegments == 0) && (Type == ACPI_TYPE_ANY)) 678 { 679 Type = ThisNode->Type; 680 } 681 682 /* Point to next name segment and make this node current */ 683 684 Path += ACPI_NAME_SIZE; 685 CurrentNode = ThisNode; 686 } 687 688 /* 689 * Always check if we need to open a new scope 690 */ 691 if (!(Flags & ACPI_NS_DONT_OPEN_SCOPE) && (WalkState)) 692 { 693 /* 694 * If entry is a type which opens a scope, push the new scope on the 695 * scope stack. 696 */ 697 if (AcpiNsOpensScope (Type)) 698 { 699 Status = AcpiDsScopeStackPush (ThisNode, Type, WalkState); 700 if (ACPI_FAILURE (Status)) 701 { 702 return_ACPI_STATUS (Status); 703 } 704 } 705 } 706 707 *ReturnNode = ThisNode; 708 return_ACPI_STATUS (AE_OK); 709} 710 711