1 /*******************************************************************************
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2006, R. Byron Moore
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
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
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44 #include <acpi/acpi.h>
45 #include <acpi/amlcode.h>
46 #include <acpi/acnamesp.h>
47 #include <acpi/acdispat.h>
49 #define _COMPONENT ACPI_NAMESPACE
50 ACPI_MODULE_NAME("nsaccess")
52 /*******************************************************************************
54 * FUNCTION: acpi_ns_root_initialize
60 * DESCRIPTION: Allocate and initialize the default root named objects
62 * MUTEX: Locks namespace for entire execution
64 ******************************************************************************/
65 acpi_status acpi_ns_root_initialize(void)
68 const struct acpi_predefined_names *init_val = NULL;
69 struct acpi_namespace_node *new_node;
70 union acpi_operand_object *obj_desc;
71 acpi_string val = NULL;
73 ACPI_FUNCTION_TRACE("ns_root_initialize");
75 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
76 if (ACPI_FAILURE(status)) {
77 return_ACPI_STATUS(status);
81 * The global root ptr is initially NULL, so a non-NULL value indicates
82 * that acpi_ns_root_initialize() has already been called; just return.
84 if (acpi_gbl_root_node) {
90 * Tell the rest of the subsystem that the root is initialized
91 * (This is OK because the namespace is locked)
93 acpi_gbl_root_node = &acpi_gbl_root_node_struct;
95 /* Enter the pre-defined names in the name table */
97 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
98 "Entering predefined entries into namespace\n"));
100 for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
102 /* _OSI is optional for now, will be permanent later */
104 if (!ACPI_STRCMP(init_val->name, "_OSI")
105 && !acpi_gbl_create_osi_method) {
109 status = acpi_ns_lookup(NULL, init_val->name, init_val->type,
110 ACPI_IMODE_LOAD_PASS2,
111 ACPI_NS_NO_UPSEARCH, NULL, &new_node);
113 if (ACPI_FAILURE(status) || (!new_node)) { /* Must be on same line for code converter */
114 ACPI_EXCEPTION((AE_INFO, status,
115 "Could not create predefined name %s",
120 * Name entered successfully.
121 * If entry in pre_defined_names[] specifies an
122 * initial value, create the initial value.
125 status = acpi_os_predefined_override(init_val, &val);
126 if (ACPI_FAILURE(status)) {
128 "Could not override predefined %s",
137 * Entry requests an initial value, allocate a
141 acpi_ut_create_internal_object(init_val->type);
143 status = AE_NO_MEMORY;
144 goto unlock_and_exit;
148 * Convert value string from table entry to
149 * internal representation. Only types actually
150 * used for initial values are implemented here.
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;
158 #if defined (ACPI_ASL_COMPILER)
160 /* save the parameter count for the i_aSL compiler */
162 new_node->value = obj_desc->method.param_count;
164 /* Mark this as a very SPECIAL method */
166 obj_desc->method.method_flags =
167 AML_METHOD_INTERNAL_ONLY;
169 #ifndef ACPI_DUMP_APP
170 obj_desc->method.implementation =
171 acpi_ut_osi_implementation;
176 case ACPI_TYPE_INTEGER:
178 obj_desc->integer.value = ACPI_TO_INTEGER(val);
181 case ACPI_TYPE_STRING:
184 * Build an object around the static string
186 obj_desc->string.length =
187 (u32) ACPI_STRLEN(val);
188 obj_desc->string.pointer = val;
189 obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
192 case ACPI_TYPE_MUTEX:
194 obj_desc->mutex.node = new_node;
195 obj_desc->mutex.sync_level =
196 (u8) (ACPI_TO_INTEGER(val) - 1);
198 if (ACPI_STRCMP(init_val->name, "_GL_") == 0) {
200 * Create a counting semaphore for the
204 acpi_os_create_semaphore
205 (ACPI_NO_UNIT_LIMIT, 1,
206 &obj_desc->mutex.semaphore);
207 if (ACPI_FAILURE(status)) {
208 acpi_ut_remove_reference
210 goto unlock_and_exit;
214 * We just created the mutex for the
215 * global lock, save it
217 acpi_gbl_global_lock_semaphore =
218 obj_desc->mutex.semaphore;
222 status = acpi_os_create_semaphore(1, 1,
226 if (ACPI_FAILURE(status)) {
227 acpi_ut_remove_reference
229 goto unlock_and_exit;
237 "Unsupported initial type value %X",
239 acpi_ut_remove_reference(obj_desc);
244 /* Store pointer to value descriptor in the Node */
246 status = acpi_ns_attach_object(new_node, obj_desc,
250 /* Remove local reference to the object */
252 acpi_ut_remove_reference(obj_desc);
257 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
259 /* Save a handle to "_GPE", it is always present */
261 if (ACPI_SUCCESS(status)) {
263 acpi_ns_get_node_by_path("\\_GPE", NULL,
265 &acpi_gbl_fadt_gpe_device);
268 return_ACPI_STATUS(status);
271 /*******************************************************************************
273 * FUNCTION: acpi_ns_lookup
275 * PARAMETERS: scope_info - Current scope info block
276 * Pathname - Search pathname, in internal format
277 * (as represented in the AML stream)
278 * Type - Type associated with name
279 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
280 * Flags - Flags describing the search restrictions
281 * walk_state - Current state of the walk
282 * return_node - Where the Node is placed (if found
283 * or created successfully)
287 * DESCRIPTION: Find or enter the passed name in the name space.
288 * Log an error if name not found in Exec mode.
290 * MUTEX: Assumes namespace is locked.
292 ******************************************************************************/
295 acpi_ns_lookup(union acpi_generic_state *scope_info,
297 acpi_object_type type,
298 acpi_interpreter_mode interpreter_mode,
300 struct acpi_walk_state *walk_state,
301 struct acpi_namespace_node **return_node)
304 char *path = pathname;
305 struct acpi_namespace_node *prefix_node;
306 struct acpi_namespace_node *current_node = NULL;
307 struct acpi_namespace_node *this_node = NULL;
310 acpi_name simple_name;
311 acpi_object_type type_to_check_for;
312 acpi_object_type this_search_type;
313 u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
314 u32 local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND |
315 ACPI_NS_SEARCH_PARENT);
317 ACPI_FUNCTION_TRACE("ns_lookup");
320 return_ACPI_STATUS(AE_BAD_PARAMETER);
323 acpi_gbl_ns_lookup_count++;
324 *return_node = ACPI_ENTRY_NOT_FOUND;
326 if (!acpi_gbl_root_node) {
327 return_ACPI_STATUS(AE_NO_NAMESPACE);
331 * Get the prefix scope.
332 * A null scope means use the root scope
334 if ((!scope_info) || (!scope_info->scope.node)) {
335 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
336 "Null scope prefix, using root node (%p)\n",
337 acpi_gbl_root_node));
339 prefix_node = acpi_gbl_root_node;
341 prefix_node = scope_info->scope.node;
342 if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node) !=
343 ACPI_DESC_TYPE_NAMED) {
344 ACPI_ERROR((AE_INFO, "%p is not a namespace node [%s]",
346 acpi_ut_get_descriptor_name(prefix_node)));
347 return_ACPI_STATUS(AE_AML_INTERNAL);
351 * This node might not be a actual "scope" node (such as a
352 * Device/Method, etc.) It could be a Package or other object node.
353 * Backup up the tree to find the containing scope node.
355 while (!acpi_ns_opens_scope(prefix_node->type) &&
356 prefix_node->type != ACPI_TYPE_ANY) {
357 prefix_node = acpi_ns_get_parent_node(prefix_node);
361 /* Save type TBD: may be no longer necessary */
363 type_to_check_for = type;
366 * Begin examination of the actual pathname
370 /* A Null name_path is allowed and refers to the root */
373 this_node = acpi_gbl_root_node;
376 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
377 "Null Pathname (Zero segments), Flags=%X\n",
381 * Name pointer is valid (and must be in internal name format)
383 * Check for scope prefixes:
385 * As represented in the AML stream, a namepath consists of an
386 * optional scope prefix followed by a name segment part.
388 * If present, the scope prefix is either a Root Prefix (in
389 * which case the name is fully qualified), or one or more
390 * Parent Prefixes (in which case the name's scope is relative
391 * to the current scope).
393 if (*path == (u8) AML_ROOT_PREFIX) {
395 /* Pathname is fully qualified, start from the root */
397 this_node = acpi_gbl_root_node;
398 search_parent_flag = ACPI_NS_NO_UPSEARCH;
400 /* Point to name segment part */
404 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
405 "Path is absolute from root [%p]\n",
408 /* Pathname is relative to current scope, start there */
410 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
411 "Searching relative to prefix scope [%4.4s] (%p)\n",
412 acpi_ut_get_node_name(prefix_node),
416 * Handle multiple Parent Prefixes (carat) by just getting
417 * the parent node for each prefix instance.
419 this_node = prefix_node;
421 while (*path == (u8) AML_PARENT_PREFIX) {
423 /* Name is fully qualified, no search rules apply */
425 search_parent_flag = ACPI_NS_NO_UPSEARCH;
427 * Point past this prefix to the name segment
428 * part or the next Parent Prefix
432 /* Backup to the parent node */
435 this_node = acpi_ns_get_parent_node(this_node);
438 /* Current scope has no parent scope */
441 "ACPI path has too many parent prefixes (^) - reached beyond root node"));
442 return_ACPI_STATUS(AE_NOT_FOUND);
446 if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
447 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
448 "Search scope is [%4.4s], path has %d carat(s)\n",
449 acpi_ut_get_node_name
450 (this_node), num_carats));
455 * Determine the number of ACPI name segments in this pathname.
457 * The segment part consists of either:
458 * - A Null name segment (0)
459 * - A dual_name_prefix followed by two 4-byte name segments
460 * - A multi_name_prefix followed by a byte indicating the
461 * number of segments and the segments themselves.
462 * - A single 4-byte name segment
464 * Examine the name prefix opcode, if any, to determine the number of
470 * Null name after a root or parent prefixes. We already
471 * have the correct target node and there are no name segments.
474 type = this_node->type;
476 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
477 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
481 case AML_DUAL_NAME_PREFIX:
483 /* More than one name_seg, search rules do not apply */
485 search_parent_flag = ACPI_NS_NO_UPSEARCH;
487 /* Two segments, point to first name segment */
492 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
493 "Dual Pathname (2 segments, Flags=%X)\n",
497 case AML_MULTI_NAME_PREFIX_OP:
499 /* More than one name_seg, search rules do not apply */
501 search_parent_flag = ACPI_NS_NO_UPSEARCH;
503 /* Extract segment count, point to first name segment */
506 num_segments = (u32) (u8) * path;
509 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
510 "Multi Pathname (%d Segments, Flags=%X)\n",
511 num_segments, flags));
516 * Not a Null name, no Dual or Multi prefix, hence there is
517 * only one name segment and Pathname is already pointing to it.
521 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
522 "Simple Pathname (1 segment, Flags=%X)\n",
527 ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments, path));
531 * Search namespace for each segment of the name. Loop through and
532 * verify (or add to the namespace) each name segment.
534 * The object type is significant only at the last name
535 * segment. (We don't care about the types along the path, only
536 * the type of the final target object.)
538 this_search_type = ACPI_TYPE_ANY;
539 current_node = this_node;
540 while (num_segments && current_node) {
544 * This is the last segment, enable typechecking
546 this_search_type = type;
549 * Only allow automatic parent search (search rules) if the caller
550 * requested it AND we have a single, non-fully-qualified name_seg
552 if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
553 (flags & ACPI_NS_SEARCH_PARENT)) {
554 local_flags |= ACPI_NS_SEARCH_PARENT;
557 /* Set error flag according to caller */
559 if (flags & ACPI_NS_ERROR_IF_FOUND) {
560 local_flags |= ACPI_NS_ERROR_IF_FOUND;
564 /* Extract one ACPI name from the front of the pathname */
566 ACPI_MOVE_32_TO_32(&simple_name, path);
568 /* Try to find the single (4 character) ACPI name */
571 acpi_ns_search_and_enter(simple_name, walk_state,
572 current_node, interpreter_mode,
573 this_search_type, local_flags,
575 if (ACPI_FAILURE(status)) {
576 if (status == AE_NOT_FOUND) {
578 /* Name not found in ACPI namespace */
580 ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
581 "Name [%4.4s] not found in scope [%4.4s] %p\n",
582 (char *)&simple_name,
583 (char *)¤t_node->name,
587 *return_node = this_node;
588 return_ACPI_STATUS(status);
592 * Sanity typecheck of the target object:
594 * If 1) This is the last segment (num_segments == 0)
595 * 2) And we are looking for a specific type
596 * (Not checking for TYPE_ANY)
597 * 3) Which is not an alias
598 * 4) Which is not a local type (TYPE_SCOPE)
599 * 5) And the type of target object is known (not TYPE_ANY)
600 * 6) And target object does not match what we are looking for
602 * Then we have a type mismatch. Just warn and ignore it.
604 if ((num_segments == 0) &&
605 (type_to_check_for != ACPI_TYPE_ANY) &&
606 (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
607 (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) &&
608 (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) &&
609 (this_node->type != ACPI_TYPE_ANY) &&
610 (this_node->type != type_to_check_for)) {
612 /* Complain about a type mismatch */
614 ACPI_WARNING((AE_INFO,
615 "ns_lookup: Type mismatch on %4.4s (%s), searching for (%s)",
616 ACPI_CAST_PTR(char, &simple_name),
617 acpi_ut_get_type_name(this_node->type),
618 acpi_ut_get_type_name
619 (type_to_check_for)));
623 * If this is the last name segment and we are not looking for a
624 * specific type, but the type of found object is known, use that type
625 * to see if it opens a scope.
627 if ((num_segments == 0) && (type == ACPI_TYPE_ANY)) {
628 type = this_node->type;
631 /* Point to next name segment and make this node current */
633 path += ACPI_NAME_SIZE;
634 current_node = this_node;
638 * Always check if we need to open a new scope
640 if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
642 * If entry is a type which opens a scope, push the new scope on the
645 if (acpi_ns_opens_scope(type)) {
647 acpi_ds_scope_stack_push(this_node, type,
649 if (ACPI_FAILURE(status)) {
650 return_ACPI_STATUS(status);
655 *return_node = this_node;
656 return_ACPI_STATUS(AE_OK);