1 /*******************************************************************************
2 *
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2013, 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 }