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