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v3.1
  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#include <acpi/acpi.h>
 45#include "accommon.h"
 46#include "amlcode.h"
 47#include "acnamesp.h"
 48#include "acdispat.h"
 49
 50#define _COMPONENT          ACPI_NAMESPACE
 51ACPI_MODULE_NAME("nsaccess")
 52
 53/*******************************************************************************
 54 *
 55 * FUNCTION:    acpi_ns_root_initialize
 56 *
 57 * PARAMETERS:  None
 58 *
 59 * RETURN:      Status
 60 *
 61 * DESCRIPTION: Allocate and initialize the default root named objects
 62 *
 63 * MUTEX:       Locks namespace for entire execution
 64 *
 65 ******************************************************************************/
 66acpi_status acpi_ns_root_initialize(void)
 67{
 68	acpi_status status;
 69	const struct acpi_predefined_names *init_val = NULL;
 70	struct acpi_namespace_node *new_node;
 71	union acpi_operand_object *obj_desc;
 72	acpi_string val = NULL;
 73
 74	ACPI_FUNCTION_TRACE(ns_root_initialize);
 75
 76	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 77	if (ACPI_FAILURE(status)) {
 78		return_ACPI_STATUS(status);
 79	}
 80
 81	/*
 82	 * The global root ptr is initially NULL, so a non-NULL value indicates
 83	 * that acpi_ns_root_initialize() has already been called; just return.
 84	 */
 85	if (acpi_gbl_root_node) {
 86		status = AE_OK;
 87		goto unlock_and_exit;
 88	}
 89
 90	/*
 91	 * Tell the rest of the subsystem that the root is initialized
 92	 * (This is OK because the namespace is locked)
 93	 */
 94	acpi_gbl_root_node = &acpi_gbl_root_node_struct;
 95
 96	/* Enter the pre-defined names in the name table */
 97
 98	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 99			  "Entering predefined entries into namespace\n"));
100
101	for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
102
103		/* _OSI is optional for now, will be permanent later */
104
105		if (!ACPI_STRCMP(init_val->name, "_OSI")
106		    && !acpi_gbl_create_osi_method) {
107			continue;
108		}
109
110		status = acpi_ns_lookup(NULL, init_val->name, init_val->type,
111					ACPI_IMODE_LOAD_PASS2,
112					ACPI_NS_NO_UPSEARCH, NULL, &new_node);
113
114		if (ACPI_FAILURE(status) || (!new_node)) {	/* Must be on same line for code converter */
115			ACPI_EXCEPTION((AE_INFO, status,
116					"Could not create predefined name %s",
117					init_val->name));
 
118		}
119
120		/*
121		 * Name entered successfully. If entry in pre_defined_names[] specifies
122		 * an initial value, create the initial value.
123		 */
124		if (init_val->val) {
125			status = acpi_os_predefined_override(init_val, &val);
126			if (ACPI_FAILURE(status)) {
127				ACPI_ERROR((AE_INFO,
128					    "Could not override predefined %s",
129					    init_val->name));
130			}
131
132			if (!val) {
133				val = init_val->val;
134			}
135
136			/*
137			 * Entry requests an initial value, allocate a
138			 * descriptor for it.
139			 */
140			obj_desc =
141			    acpi_ut_create_internal_object(init_val->type);
142			if (!obj_desc) {
143				status = AE_NO_MEMORY;
144				goto unlock_and_exit;
145			}
146
147			/*
148			 * Convert value string from table entry to
149			 * internal representation. Only types actually
150			 * used for initial values are implemented here.
151			 */
152			switch (init_val->type) {
153			case ACPI_TYPE_METHOD:
 
154				obj_desc->method.param_count =
155				    (u8) ACPI_TO_INTEGER(val);
156				obj_desc->common.flags |= AOPOBJ_DATA_VALID;
157
158#if defined (ACPI_ASL_COMPILER)
159
160				/* Save the parameter count for the i_aSL compiler */
161
162				new_node->value = obj_desc->method.param_count;
163#else
164				/* Mark this as a very SPECIAL method */
165
166				obj_desc->method.info_flags =
167				    ACPI_METHOD_INTERNAL_ONLY;
168				obj_desc->method.dispatch.implementation =
169				    acpi_ut_osi_implementation;
170#endif
171				break;
172
173			case ACPI_TYPE_INTEGER:
174
175				obj_desc->integer.value = ACPI_TO_INTEGER(val);
176				break;
177
178			case ACPI_TYPE_STRING:
179
180				/* Build an object around the static string */
181
182				obj_desc->string.length =
183				    (u32) ACPI_STRLEN(val);
184				obj_desc->string.pointer = val;
185				obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
186				break;
187
188			case ACPI_TYPE_MUTEX:
189
190				obj_desc->mutex.node = new_node;
191				obj_desc->mutex.sync_level =
192				    (u8) (ACPI_TO_INTEGER(val) - 1);
193
194				/* Create a mutex */
195
196				status =
197				    acpi_os_create_mutex(&obj_desc->mutex.
198							 os_mutex);
199				if (ACPI_FAILURE(status)) {
200					acpi_ut_remove_reference(obj_desc);
201					goto unlock_and_exit;
202				}
203
204				/* Special case for ACPI Global Lock */
205
206				if (ACPI_STRCMP(init_val->name, "_GL_") == 0) {
207					acpi_gbl_global_lock_mutex = obj_desc;
208
209					/* Create additional counting semaphore for global lock */
210
211					status =
212					    acpi_os_create_semaphore(1, 0,
213								     &acpi_gbl_global_lock_semaphore);
214					if (ACPI_FAILURE(status)) {
215						acpi_ut_remove_reference
216						    (obj_desc);
217						goto unlock_and_exit;
218					}
219				}
220				break;
221
222			default:
223
224				ACPI_ERROR((AE_INFO,
225					    "Unsupported initial type value 0x%X",
226					    init_val->type));
227				acpi_ut_remove_reference(obj_desc);
228				obj_desc = NULL;
229				continue;
230			}
231
232			/* Store pointer to value descriptor in the Node */
233
234			status = acpi_ns_attach_object(new_node, obj_desc,
235						       obj_desc->common.type);
236
237			/* Remove local reference to the object */
238
239			acpi_ut_remove_reference(obj_desc);
240		}
241	}
242
243      unlock_and_exit:
244	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
245
246	/* Save a handle to "_GPE", it is always present */
247
248	if (ACPI_SUCCESS(status)) {
249		status = acpi_ns_get_node(NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
250					  &acpi_gbl_fadt_gpe_device);
251	}
252
253	return_ACPI_STATUS(status);
254}
255
256/*******************************************************************************
257 *
258 * FUNCTION:    acpi_ns_lookup
259 *
260 * PARAMETERS:  scope_info      - Current scope info block
261 *              Pathname        - Search pathname, in internal format
262 *                                (as represented in the AML stream)
263 *              Type            - Type associated with name
264 *              interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
265 *              Flags           - Flags describing the search restrictions
266 *              walk_state      - Current state of the walk
267 *              return_node     - Where the Node is placed (if found
268 *                                or created successfully)
269 *
270 * RETURN:      Status
271 *
272 * DESCRIPTION: Find or enter the passed name in the name space.
273 *              Log an error if name not found in Exec mode.
274 *
275 * MUTEX:       Assumes namespace is locked.
276 *
277 ******************************************************************************/
278
279acpi_status
280acpi_ns_lookup(union acpi_generic_state *scope_info,
281	       char *pathname,
282	       acpi_object_type type,
283	       acpi_interpreter_mode interpreter_mode,
284	       u32 flags,
285	       struct acpi_walk_state *walk_state,
286	       struct acpi_namespace_node **return_node)
287{
288	acpi_status status;
289	char *path = pathname;
290	struct acpi_namespace_node *prefix_node;
291	struct acpi_namespace_node *current_node = NULL;
292	struct acpi_namespace_node *this_node = NULL;
293	u32 num_segments;
294	u32 num_carats;
295	acpi_name simple_name;
296	acpi_object_type type_to_check_for;
297	acpi_object_type this_search_type;
298	u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
299	u32 local_flags;
300
301	ACPI_FUNCTION_TRACE(ns_lookup);
302
303	if (!return_node) {
304		return_ACPI_STATUS(AE_BAD_PARAMETER);
305	}
306
307	local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT);
 
 
308	*return_node = ACPI_ENTRY_NOT_FOUND;
309	acpi_gbl_ns_lookup_count++;
310
311	if (!acpi_gbl_root_node) {
312		return_ACPI_STATUS(AE_NO_NAMESPACE);
313	}
314
315	/* Get the prefix scope. A null scope means use the root scope */
316
317	if ((!scope_info) || (!scope_info->scope.node)) {
318		ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
319				  "Null scope prefix, using root node (%p)\n",
320				  acpi_gbl_root_node));
321
322		prefix_node = acpi_gbl_root_node;
323	} else {
324		prefix_node = scope_info->scope.node;
325		if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) !=
326		    ACPI_DESC_TYPE_NAMED) {
327			ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]",
328				    prefix_node,
329				    acpi_ut_get_descriptor_name(prefix_node)));
330			return_ACPI_STATUS(AE_AML_INTERNAL);
331		}
332
333		if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) {
334			/*
335			 * This node might not be a actual "scope" node (such as a
336			 * Device/Method, etc.)  It could be a Package or other object
337			 * node. Backup up the tree to find the containing scope node.
338			 */
339			while (!acpi_ns_opens_scope(prefix_node->type) &&
340			       prefix_node->type != ACPI_TYPE_ANY) {
341				prefix_node = prefix_node->parent;
342			}
343		}
344	}
345
346	/* Save type. TBD: may be no longer necessary */
347
348	type_to_check_for = type;
349
350	/*
351	 * Begin examination of the actual pathname
352	 */
353	if (!pathname) {
354
355		/* A Null name_path is allowed and refers to the root */
356
357		num_segments = 0;
358		this_node = acpi_gbl_root_node;
359		path = "";
360
361		ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
362				  "Null Pathname (Zero segments), Flags=%X\n",
363				  flags));
364	} else {
365		/*
366		 * Name pointer is valid (and must be in internal name format)
367		 *
368		 * Check for scope prefixes:
369		 *
370		 * As represented in the AML stream, a namepath consists of an
371		 * optional scope prefix followed by a name segment part.
372		 *
373		 * If present, the scope prefix is either a Root Prefix (in
374		 * which case the name is fully qualified), or one or more
375		 * Parent Prefixes (in which case the name's scope is relative
376		 * to the current scope).
377		 */
378		if (*path == (u8) AML_ROOT_PREFIX) {
379
380			/* Pathname is fully qualified, start from the root */
381
382			this_node = acpi_gbl_root_node;
383			search_parent_flag = ACPI_NS_NO_UPSEARCH;
384
385			/* Point to name segment part */
386
387			path++;
388
389			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
390					  "Path is absolute from root [%p]\n",
391					  this_node));
392		} else {
393			/* Pathname is relative to current scope, start there */
394
395			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
396					  "Searching relative to prefix scope [%4.4s] (%p)\n",
397					  acpi_ut_get_node_name(prefix_node),
398					  prefix_node));
399
400			/*
401			 * Handle multiple Parent Prefixes (carat) by just getting
402			 * the parent node for each prefix instance.
403			 */
404			this_node = prefix_node;
405			num_carats = 0;
406			while (*path == (u8) AML_PARENT_PREFIX) {
407
408				/* Name is fully qualified, no search rules apply */
409
410				search_parent_flag = ACPI_NS_NO_UPSEARCH;
411
412				/*
413				 * Point past this prefix to the name segment
414				 * part or the next Parent Prefix
415				 */
416				path++;
417
418				/* Backup to the parent node */
419
420				num_carats++;
421				this_node = this_node->parent;
422				if (!this_node) {
423
424					/* Current scope has no parent scope */
425
426					ACPI_ERROR((AE_INFO,
427						    "ACPI path has too many parent prefixes (^) "
428						    "- reached beyond root node"));
 
429					return_ACPI_STATUS(AE_NOT_FOUND);
430				}
431			}
432
433			if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
434				ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
435						  "Search scope is [%4.4s], path has %u carat(s)\n",
436						  acpi_ut_get_node_name
437						  (this_node), num_carats));
438			}
439		}
440
441		/*
442		 * Determine the number of ACPI name segments in this pathname.
443		 *
444		 * The segment part consists of either:
445		 *  - A Null name segment (0)
446		 *  - A dual_name_prefix followed by two 4-byte name segments
447		 *  - A multi_name_prefix followed by a byte indicating the
448		 *      number of segments and the segments themselves.
449		 *  - A single 4-byte name segment
450		 *
451		 * Examine the name prefix opcode, if any, to determine the number of
452		 * segments.
453		 */
454		switch (*path) {
455		case 0:
456			/*
457			 * Null name after a root or parent prefixes. We already
458			 * have the correct target node and there are no name segments.
459			 */
460			num_segments = 0;
461			type = this_node->type;
462
463			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
464					  "Prefix-only Pathname (Zero name segments), Flags=%X\n",
465					  flags));
466			break;
467
468		case AML_DUAL_NAME_PREFIX:
469
470			/* More than one name_seg, search rules do not apply */
471
472			search_parent_flag = ACPI_NS_NO_UPSEARCH;
473
474			/* Two segments, point to first name segment */
475
476			num_segments = 2;
477			path++;
478
479			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
480					  "Dual Pathname (2 segments, Flags=%X)\n",
481					  flags));
482			break;
483
484		case AML_MULTI_NAME_PREFIX_OP:
485
486			/* More than one name_seg, search rules do not apply */
487
488			search_parent_flag = ACPI_NS_NO_UPSEARCH;
489
490			/* Extract segment count, point to first name segment */
491
492			path++;
493			num_segments = (u32) (u8) * path;
494			path++;
495
496			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
497					  "Multi Pathname (%u Segments, Flags=%X)\n",
498					  num_segments, flags));
499			break;
500
501		default:
502			/*
503			 * Not a Null name, no Dual or Multi prefix, hence there is
504			 * only one name segment and Pathname is already pointing to it.
505			 */
506			num_segments = 1;
507
508			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
509					  "Simple Pathname (1 segment, Flags=%X)\n",
510					  flags));
511			break;
512		}
513
514		ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path));
515	}
516
517	/*
518	 * Search namespace for each segment of the name. Loop through and
519	 * verify (or add to the namespace) each name segment.
520	 *
521	 * The object type is significant only at the last name
522	 * segment. (We don't care about the types along the path, only
523	 * the type of the final target object.)
524	 */
525	this_search_type = ACPI_TYPE_ANY;
526	current_node = this_node;
527	while (num_segments && current_node) {
528		num_segments--;
529		if (!num_segments) {
530
531			/* This is the last segment, enable typechecking */
532
533			this_search_type = type;
534
535			/*
536			 * Only allow automatic parent search (search rules) if the caller
537			 * requested it AND we have a single, non-fully-qualified name_seg
538			 */
539			if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
540			    (flags & ACPI_NS_SEARCH_PARENT)) {
541				local_flags |= ACPI_NS_SEARCH_PARENT;
542			}
543
544			/* Set error flag according to caller */
545
546			if (flags & ACPI_NS_ERROR_IF_FOUND) {
547				local_flags |= ACPI_NS_ERROR_IF_FOUND;
 
 
 
 
 
 
548			}
549		}
550
551		/* Extract one ACPI name from the front of the pathname */
552
553		ACPI_MOVE_32_TO_32(&simple_name, path);
554
555		/* Try to find the single (4 character) ACPI name */
556
557		status =
558		    acpi_ns_search_and_enter(simple_name, walk_state,
559					     current_node, interpreter_mode,
560					     this_search_type, local_flags,
561					     &this_node);
562		if (ACPI_FAILURE(status)) {
563			if (status == AE_NOT_FOUND) {
564
565				/* Name not found in ACPI namespace */
566
567				ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
568						  "Name [%4.4s] not found in scope [%4.4s] %p\n",
569						  (char *)&simple_name,
570						  (char *)&current_node->name,
571						  current_node));
572			}
573
574			*return_node = this_node;
575			return_ACPI_STATUS(status);
576		}
577
578		/* More segments to follow? */
579
580		if (num_segments > 0) {
581			/*
582			 * If we have an alias to an object that opens a scope (such as a
583			 * device or processor), we need to dereference the alias here so
584			 * that we can access any children of the original node (via the
585			 * remaining segments).
586			 */
587			if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) {
588				if (!this_node->object) {
589					return_ACPI_STATUS(AE_NOT_EXIST);
590				}
591
592				if (acpi_ns_opens_scope
593				    (((struct acpi_namespace_node *)
594				      this_node->object)->type)) {
595					this_node =
596					    (struct acpi_namespace_node *)
597					    this_node->object;
598				}
599			}
600		}
601
602		/* Special handling for the last segment (num_segments == 0) */
603
604		else {
605			/*
606			 * Sanity typecheck of the target object:
607			 *
608			 * If 1) This is the last segment (num_segments == 0)
609			 *    2) And we are looking for a specific type
610			 *       (Not checking for TYPE_ANY)
611			 *    3) Which is not an alias
612			 *    4) Which is not a local type (TYPE_SCOPE)
613			 *    5) And the type of target object is known (not TYPE_ANY)
614			 *    6) And target object does not match what we are looking for
615			 *
616			 * Then we have a type mismatch. Just warn and ignore it.
617			 */
618			if ((type_to_check_for != ACPI_TYPE_ANY) &&
619			    (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
620			    (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS)
621			    && (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE)
622			    && (this_node->type != ACPI_TYPE_ANY)
623			    && (this_node->type != type_to_check_for)) {
624
625				/* Complain about a type mismatch */
626
627				ACPI_WARNING((AE_INFO,
628					      "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
629					      ACPI_CAST_PTR(char, &simple_name),
630					      acpi_ut_get_type_name(this_node->
631								    type),
632					      acpi_ut_get_type_name
633					      (type_to_check_for)));
634			}
635
636			/*
637			 * If this is the last name segment and we are not looking for a
638			 * specific type, but the type of found object is known, use that
639			 * type to (later) see if it opens a scope.
640			 */
641			if (type == ACPI_TYPE_ANY) {
642				type = this_node->type;
643			}
644		}
645
646		/* Point to next name segment and make this node current */
647
648		path += ACPI_NAME_SIZE;
649		current_node = this_node;
650	}
651
652	/* Always check if we need to open a new scope */
653
654	if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
655		/*
656		 * If entry is a type which opens a scope, push the new scope on the
657		 * scope stack.
658		 */
659		if (acpi_ns_opens_scope(type)) {
660			status =
661			    acpi_ds_scope_stack_push(this_node, type,
662						     walk_state);
663			if (ACPI_FAILURE(status)) {
664				return_ACPI_STATUS(status);
665			}
666		}
667	}
668
669	*return_node = this_node;
670	return_ACPI_STATUS(AE_OK);
671}
v4.10.11
  1/*******************************************************************************
  2 *
  3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
  4 *
  5 ******************************************************************************/
  6
  7/*
  8 * Copyright (C) 2000 - 2016, 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/acpi.h>
 45#include "accommon.h"
 46#include "amlcode.h"
 47#include "acnamesp.h"
 48#include "acdispat.h"
 49
 50#define _COMPONENT          ACPI_NAMESPACE
 51ACPI_MODULE_NAME("nsaccess")
 52
 53/*******************************************************************************
 54 *
 55 * FUNCTION:    acpi_ns_root_initialize
 56 *
 57 * PARAMETERS:  None
 58 *
 59 * RETURN:      Status
 60 *
 61 * DESCRIPTION: Allocate and initialize the default root named objects
 62 *
 63 * MUTEX:       Locks namespace for entire execution
 64 *
 65 ******************************************************************************/
 66acpi_status acpi_ns_root_initialize(void)
 67{
 68	acpi_status status;
 69	const struct acpi_predefined_names *init_val = NULL;
 70	struct acpi_namespace_node *new_node;
 71	union acpi_operand_object *obj_desc;
 72	acpi_string val = NULL;
 73
 74	ACPI_FUNCTION_TRACE(ns_root_initialize);
 75
 76	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 77	if (ACPI_FAILURE(status)) {
 78		return_ACPI_STATUS(status);
 79	}
 80
 81	/*
 82	 * The global root ptr is initially NULL, so a non-NULL value indicates
 83	 * that acpi_ns_root_initialize() has already been called; just return.
 84	 */
 85	if (acpi_gbl_root_node) {
 86		status = AE_OK;
 87		goto unlock_and_exit;
 88	}
 89
 90	/*
 91	 * Tell the rest of the subsystem that the root is initialized
 92	 * (This is OK because the namespace is locked)
 93	 */
 94	acpi_gbl_root_node = &acpi_gbl_root_node_struct;
 95
 96	/* Enter the pre-defined names in the name table */
 97
 98	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 99			  "Entering predefined entries into namespace\n"));
100
101	for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
102
103		/* _OSI is optional for now, will be permanent later */
104
105		if (!strcmp(init_val->name, "_OSI")
106		    && !acpi_gbl_create_osi_method) {
107			continue;
108		}
109
110		status =
111		    acpi_ns_lookup(NULL, ACPI_CAST_PTR(char, init_val->name),
112				   init_val->type, ACPI_IMODE_LOAD_PASS2,
113				   ACPI_NS_NO_UPSEARCH, NULL, &new_node);
114		if (ACPI_FAILURE(status)) {
115			ACPI_EXCEPTION((AE_INFO, status,
116					"Could not create predefined name %s",
117					init_val->name));
118			continue;
119		}
120
121		/*
122		 * Name entered successfully. If entry in pre_defined_names[] specifies
123		 * an initial value, create the initial value.
124		 */
125		if (init_val->val) {
126			status = acpi_os_predefined_override(init_val, &val);
127			if (ACPI_FAILURE(status)) {
128				ACPI_ERROR((AE_INFO,
129					    "Could not override predefined %s",
130					    init_val->name));
131			}
132
133			if (!val) {
134				val = init_val->val;
135			}
136
137			/*
138			 * Entry requests an initial value, allocate a
139			 * descriptor for it.
140			 */
141			obj_desc =
142			    acpi_ut_create_internal_object(init_val->type);
143			if (!obj_desc) {
144				status = AE_NO_MEMORY;
145				goto unlock_and_exit;
146			}
147
148			/*
149			 * Convert value string from table entry to
150			 * internal representation. Only types actually
151			 * used for initial values are implemented here.
152			 */
153			switch (init_val->type) {
154			case ACPI_TYPE_METHOD:
155
156				obj_desc->method.param_count =
157				    (u8) ACPI_TO_INTEGER(val);
158				obj_desc->common.flags |= AOPOBJ_DATA_VALID;
159
160#if defined (ACPI_ASL_COMPILER)
161
162				/* Save the parameter count for the iASL compiler */
163
164				new_node->value = obj_desc->method.param_count;
165#else
166				/* Mark this as a very SPECIAL method */
167
168				obj_desc->method.info_flags =
169				    ACPI_METHOD_INTERNAL_ONLY;
170				obj_desc->method.dispatch.implementation =
171				    acpi_ut_osi_implementation;
172#endif
173				break;
174
175			case ACPI_TYPE_INTEGER:
176
177				obj_desc->integer.value = ACPI_TO_INTEGER(val);
178				break;
179
180			case ACPI_TYPE_STRING:
181
182				/* Build an object around the static string */
183
184				obj_desc->string.length = (u32)strlen(val);
 
185				obj_desc->string.pointer = val;
186				obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
187				break;
188
189			case ACPI_TYPE_MUTEX:
190
191				obj_desc->mutex.node = new_node;
192				obj_desc->mutex.sync_level =
193				    (u8) (ACPI_TO_INTEGER(val) - 1);
194
195				/* Create a mutex */
196
197				status =
198				    acpi_os_create_mutex(&obj_desc->mutex.
199							 os_mutex);
200				if (ACPI_FAILURE(status)) {
201					acpi_ut_remove_reference(obj_desc);
202					goto unlock_and_exit;
203				}
204
205				/* Special case for ACPI Global Lock */
206
207				if (strcmp(init_val->name, "_GL_") == 0) {
208					acpi_gbl_global_lock_mutex = obj_desc;
209
210					/* Create additional counting semaphore for global lock */
211
212					status =
213					    acpi_os_create_semaphore(1, 0,
214								     &acpi_gbl_global_lock_semaphore);
215					if (ACPI_FAILURE(status)) {
216						acpi_ut_remove_reference
217						    (obj_desc);
218						goto unlock_and_exit;
219					}
220				}
221				break;
222
223			default:
224
225				ACPI_ERROR((AE_INFO,
226					    "Unsupported initial type value 0x%X",
227					    init_val->type));
228				acpi_ut_remove_reference(obj_desc);
229				obj_desc = NULL;
230				continue;
231			}
232
233			/* Store pointer to value descriptor in the Node */
234
235			status = acpi_ns_attach_object(new_node, obj_desc,
236						       obj_desc->common.type);
237
238			/* Remove local reference to the object */
239
240			acpi_ut_remove_reference(obj_desc);
241		}
242	}
243
244unlock_and_exit:
245	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
246
247	/* Save a handle to "_GPE", it is always present */
248
249	if (ACPI_SUCCESS(status)) {
250		status = acpi_ns_get_node(NULL, "\\_GPE", ACPI_NS_NO_UPSEARCH,
251					  &acpi_gbl_fadt_gpe_device);
252	}
253
254	return_ACPI_STATUS(status);
255}
256
257/*******************************************************************************
258 *
259 * FUNCTION:    acpi_ns_lookup
260 *
261 * PARAMETERS:  scope_info      - Current scope info block
262 *              pathname        - Search pathname, in internal format
263 *                                (as represented in the AML stream)
264 *              type            - Type associated with name
265 *              interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
266 *              flags           - Flags describing the search restrictions
267 *              walk_state      - Current state of the walk
268 *              return_node     - Where the Node is placed (if found
269 *                                or created successfully)
270 *
271 * RETURN:      Status
272 *
273 * DESCRIPTION: Find or enter the passed name in the name space.
274 *              Log an error if name not found in Exec mode.
275 *
276 * MUTEX:       Assumes namespace is locked.
277 *
278 ******************************************************************************/
279
280acpi_status
281acpi_ns_lookup(union acpi_generic_state *scope_info,
282	       char *pathname,
283	       acpi_object_type type,
284	       acpi_interpreter_mode interpreter_mode,
285	       u32 flags,
286	       struct acpi_walk_state *walk_state,
287	       struct acpi_namespace_node **return_node)
288{
289	acpi_status status;
290	char *path = pathname;
291	struct acpi_namespace_node *prefix_node;
292	struct acpi_namespace_node *current_node = NULL;
293	struct acpi_namespace_node *this_node = NULL;
294	u32 num_segments;
295	u32 num_carats;
296	acpi_name simple_name;
297	acpi_object_type type_to_check_for;
298	acpi_object_type this_search_type;
299	u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
300	u32 local_flags;
301
302	ACPI_FUNCTION_TRACE(ns_lookup);
303
304	if (!return_node) {
305		return_ACPI_STATUS(AE_BAD_PARAMETER);
306	}
307
308	local_flags = flags &
309	    ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND |
310	      ACPI_NS_SEARCH_PARENT);
311	*return_node = ACPI_ENTRY_NOT_FOUND;
312	acpi_gbl_ns_lookup_count++;
313
314	if (!acpi_gbl_root_node) {
315		return_ACPI_STATUS(AE_NO_NAMESPACE);
316	}
317
318	/* Get the prefix scope. A null scope means use the root scope */
319
320	if ((!scope_info) || (!scope_info->scope.node)) {
321		ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
322				  "Null scope prefix, using root node (%p)\n",
323				  acpi_gbl_root_node));
324
325		prefix_node = acpi_gbl_root_node;
326	} else {
327		prefix_node = scope_info->scope.node;
328		if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) !=
329		    ACPI_DESC_TYPE_NAMED) {
330			ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]",
331				    prefix_node,
332				    acpi_ut_get_descriptor_name(prefix_node)));
333			return_ACPI_STATUS(AE_AML_INTERNAL);
334		}
335
336		if (!(flags & ACPI_NS_PREFIX_IS_SCOPE)) {
337			/*
338			 * This node might not be a actual "scope" node (such as a
339			 * Device/Method, etc.)  It could be a Package or other object
340			 * node. Backup up the tree to find the containing scope node.
341			 */
342			while (!acpi_ns_opens_scope(prefix_node->type) &&
343			       prefix_node->type != ACPI_TYPE_ANY) {
344				prefix_node = prefix_node->parent;
345			}
346		}
347	}
348
349	/* Save type. TBD: may be no longer necessary */
350
351	type_to_check_for = type;
352
353	/*
354	 * Begin examination of the actual pathname
355	 */
356	if (!pathname) {
357
358		/* A Null name_path is allowed and refers to the root */
359
360		num_segments = 0;
361		this_node = acpi_gbl_root_node;
362		path = "";
363
364		ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
365				  "Null Pathname (Zero segments), Flags=%X\n",
366				  flags));
367	} else {
368		/*
369		 * Name pointer is valid (and must be in internal name format)
370		 *
371		 * Check for scope prefixes:
372		 *
373		 * As represented in the AML stream, a namepath consists of an
374		 * optional scope prefix followed by a name segment part.
375		 *
376		 * If present, the scope prefix is either a Root Prefix (in
377		 * which case the name is fully qualified), or one or more
378		 * Parent Prefixes (in which case the name's scope is relative
379		 * to the current scope).
380		 */
381		if (*path == (u8) AML_ROOT_PREFIX) {
382
383			/* Pathname is fully qualified, start from the root */
384
385			this_node = acpi_gbl_root_node;
386			search_parent_flag = ACPI_NS_NO_UPSEARCH;
387
388			/* Point to name segment part */
389
390			path++;
391
392			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
393					  "Path is absolute from root [%p]\n",
394					  this_node));
395		} else {
396			/* Pathname is relative to current scope, start there */
397
398			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
399					  "Searching relative to prefix scope [%4.4s] (%p)\n",
400					  acpi_ut_get_node_name(prefix_node),
401					  prefix_node));
402
403			/*
404			 * Handle multiple Parent Prefixes (carat) by just getting
405			 * the parent node for each prefix instance.
406			 */
407			this_node = prefix_node;
408			num_carats = 0;
409			while (*path == (u8) AML_PARENT_PREFIX) {
410
411				/* Name is fully qualified, no search rules apply */
412
413				search_parent_flag = ACPI_NS_NO_UPSEARCH;
414
415				/*
416				 * Point past this prefix to the name segment
417				 * part or the next Parent Prefix
418				 */
419				path++;
420
421				/* Backup to the parent node */
422
423				num_carats++;
424				this_node = this_node->parent;
425				if (!this_node) {
426
427					/* Current scope has no parent scope */
428
429					ACPI_ERROR((AE_INFO,
430						    "%s: Path has too many parent prefixes (^) "
431						    "- reached beyond root node",
432						    pathname));
433					return_ACPI_STATUS(AE_NOT_FOUND);
434				}
435			}
436
437			if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
438				ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
439						  "Search scope is [%4.4s], path has %u carat(s)\n",
440						  acpi_ut_get_node_name
441						  (this_node), num_carats));
442			}
443		}
444
445		/*
446		 * Determine the number of ACPI name segments in this pathname.
447		 *
448		 * The segment part consists of either:
449		 *  - A Null name segment (0)
450		 *  - A dual_name_prefix followed by two 4-byte name segments
451		 *  - A multi_name_prefix followed by a byte indicating the
452		 *      number of segments and the segments themselves.
453		 *  - A single 4-byte name segment
454		 *
455		 * Examine the name prefix opcode, if any, to determine the number of
456		 * segments.
457		 */
458		switch (*path) {
459		case 0:
460			/*
461			 * Null name after a root or parent prefixes. We already
462			 * have the correct target node and there are no name segments.
463			 */
464			num_segments = 0;
465			type = this_node->type;
466
467			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
468					  "Prefix-only Pathname (Zero name segments), Flags=%X\n",
469					  flags));
470			break;
471
472		case AML_DUAL_NAME_PREFIX:
473
474			/* More than one name_seg, search rules do not apply */
475
476			search_parent_flag = ACPI_NS_NO_UPSEARCH;
477
478			/* Two segments, point to first name segment */
479
480			num_segments = 2;
481			path++;
482
483			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
484					  "Dual Pathname (2 segments, Flags=%X)\n",
485					  flags));
486			break;
487
488		case AML_MULTI_NAME_PREFIX_OP:
489
490			/* More than one name_seg, search rules do not apply */
491
492			search_parent_flag = ACPI_NS_NO_UPSEARCH;
493
494			/* Extract segment count, point to first name segment */
495
496			path++;
497			num_segments = (u32) (u8) * path;
498			path++;
499
500			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
501					  "Multi Pathname (%u Segments, Flags=%X)\n",
502					  num_segments, flags));
503			break;
504
505		default:
506			/*
507			 * Not a Null name, no Dual or Multi prefix, hence there is
508			 * only one name segment and Pathname is already pointing to it.
509			 */
510			num_segments = 1;
511
512			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
513					  "Simple Pathname (1 segment, Flags=%X)\n",
514					  flags));
515			break;
516		}
517
518		ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path));
519	}
520
521	/*
522	 * Search namespace for each segment of the name. Loop through and
523	 * verify (or add to the namespace) each name segment.
524	 *
525	 * The object type is significant only at the last name
526	 * segment. (We don't care about the types along the path, only
527	 * the type of the final target object.)
528	 */
529	this_search_type = ACPI_TYPE_ANY;
530	current_node = this_node;
531	while (num_segments && current_node) {
532		num_segments--;
533		if (!num_segments) {
534
535			/* This is the last segment, enable typechecking */
536
537			this_search_type = type;
538
539			/*
540			 * Only allow automatic parent search (search rules) if the caller
541			 * requested it AND we have a single, non-fully-qualified name_seg
542			 */
543			if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
544			    (flags & ACPI_NS_SEARCH_PARENT)) {
545				local_flags |= ACPI_NS_SEARCH_PARENT;
546			}
547
548			/* Set error flag according to caller */
549
550			if (flags & ACPI_NS_ERROR_IF_FOUND) {
551				local_flags |= ACPI_NS_ERROR_IF_FOUND;
552			}
553
554			/* Set override flag according to caller */
555
556			if (flags & ACPI_NS_OVERRIDE_IF_FOUND) {
557				local_flags |= ACPI_NS_OVERRIDE_IF_FOUND;
558			}
559		}
560
561		/* Extract one ACPI name from the front of the pathname */
562
563		ACPI_MOVE_32_TO_32(&simple_name, path);
564
565		/* Try to find the single (4 character) ACPI name */
566
567		status =
568		    acpi_ns_search_and_enter(simple_name, walk_state,
569					     current_node, interpreter_mode,
570					     this_search_type, local_flags,
571					     &this_node);
572		if (ACPI_FAILURE(status)) {
573			if (status == AE_NOT_FOUND) {
574
575				/* Name not found in ACPI namespace */
576
577				ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
578						  "Name [%4.4s] not found in scope [%4.4s] %p\n",
579						  (char *)&simple_name,
580						  (char *)&current_node->name,
581						  current_node));
582			}
583
584			*return_node = this_node;
585			return_ACPI_STATUS(status);
586		}
587
588		/* More segments to follow? */
589
590		if (num_segments > 0) {
591			/*
592			 * If we have an alias to an object that opens a scope (such as a
593			 * device or processor), we need to dereference the alias here so
594			 * that we can access any children of the original node (via the
595			 * remaining segments).
596			 */
597			if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) {
598				if (!this_node->object) {
599					return_ACPI_STATUS(AE_NOT_EXIST);
600				}
601
602				if (acpi_ns_opens_scope
603				    (((struct acpi_namespace_node *)
604				      this_node->object)->type)) {
605					this_node =
606					    (struct acpi_namespace_node *)
607					    this_node->object;
608				}
609			}
610		}
611
612		/* Special handling for the last segment (num_segments == 0) */
613
614		else {
615			/*
616			 * Sanity typecheck of the target object:
617			 *
618			 * If 1) This is the last segment (num_segments == 0)
619			 *    2) And we are looking for a specific type
620			 *       (Not checking for TYPE_ANY)
621			 *    3) Which is not an alias
622			 *    4) Which is not a local type (TYPE_SCOPE)
623			 *    5) And the type of target object is known (not TYPE_ANY)
624			 *    6) And target object does not match what we are looking for
625			 *
626			 * Then we have a type mismatch. Just warn and ignore it.
627			 */
628			if ((type_to_check_for != ACPI_TYPE_ANY) &&
629			    (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
630			    (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS)
631			    && (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE)
632			    && (this_node->type != ACPI_TYPE_ANY)
633			    && (this_node->type != type_to_check_for)) {
634
635				/* Complain about a type mismatch */
636
637				ACPI_WARNING((AE_INFO,
638					      "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
639					      ACPI_CAST_PTR(char, &simple_name),
640					      acpi_ut_get_type_name(this_node->
641								    type),
642					      acpi_ut_get_type_name
643					      (type_to_check_for)));
644			}
645
646			/*
647			 * If this is the last name segment and we are not looking for a
648			 * specific type, but the type of found object is known, use that
649			 * type to (later) see if it opens a scope.
650			 */
651			if (type == ACPI_TYPE_ANY) {
652				type = this_node->type;
653			}
654		}
655
656		/* Point to next name segment and make this node current */
657
658		path += ACPI_NAME_SIZE;
659		current_node = this_node;
660	}
661
662	/* Always check if we need to open a new scope */
663
664	if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
665		/*
666		 * If entry is a type which opens a scope, push the new scope on the
667		 * scope stack.
668		 */
669		if (acpi_ns_opens_scope(type)) {
670			status =
671			    acpi_ds_scope_stack_push(this_node, type,
672						     walk_state);
673			if (ACPI_FAILURE(status)) {
674				return_ACPI_STATUS(status);
675			}
676		}
677	}
678
679	*return_node = this_node;
680	return_ACPI_STATUS(AE_OK);
681}