1 /*******************************************************************************
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2004, 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
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45 #include <acpi/acpi.h>
46 #include <acpi/amlcode.h>
47 #include <acpi/acnamesp.h>
48 #include <acpi/acdispat.h>
51 #define _COMPONENT ACPI_NAMESPACE
52 ACPI_MODULE_NAME ("nsaccess")
55 /*******************************************************************************
57 * FUNCTION: acpi_ns_root_initialize
63 * DESCRIPTION: Allocate and initialize the default root named objects
65 * MUTEX: Locks namespace for entire execution
67 ******************************************************************************/
70 acpi_ns_root_initialize (void)
73 const struct acpi_predefined_names *init_val = NULL;
74 struct acpi_namespace_node *new_node;
75 union acpi_operand_object *obj_desc;
76 acpi_string val = NULL;
79 ACPI_FUNCTION_TRACE ("ns_root_initialize");
82 status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
83 if (ACPI_FAILURE (status)) {
84 return_ACPI_STATUS (status);
88 * The global root ptr is initially NULL, so a non-NULL value indicates
89 * that acpi_ns_root_initialize() has already been called; just return.
91 if (acpi_gbl_root_node) {
97 * Tell the rest of the subsystem that the root is initialized
98 * (This is OK because the namespace is locked)
100 acpi_gbl_root_node = &acpi_gbl_root_node_struct;
102 /* Enter the pre-defined names in the name table */
104 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
105 "Entering predefined entries into namespace\n"));
107 for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
108 /* _OSI is optional for now, will be permanent later */
110 if (!ACPI_STRCMP (init_val->name, "_OSI") && !acpi_gbl_create_osi_method) {
114 status = acpi_ns_lookup (NULL, init_val->name, init_val->type,
115 ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH,
118 if (ACPI_FAILURE (status) || (!new_node)) /* Must be on same line for code converter */ {
119 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
120 "Could not create predefined name %s, %s\n",
121 init_val->name, acpi_format_exception (status)));
125 * Name entered successfully.
126 * If entry in pre_defined_names[] specifies an
127 * initial value, create the initial value.
130 status = acpi_os_predefined_override (init_val, &val);
131 if (ACPI_FAILURE (status)) {
132 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
133 "Could not override predefined %s\n",
142 * Entry requests an initial value, allocate a
145 obj_desc = acpi_ut_create_internal_object (init_val->type);
147 status = AE_NO_MEMORY;
148 goto unlock_and_exit;
152 * Convert value string from table entry to
153 * internal representation. Only types actually
154 * used for initial values are implemented here.
156 switch (init_val->type) {
157 case ACPI_TYPE_METHOD:
158 obj_desc->method.param_count = (u8) ACPI_STRTOUL
160 obj_desc->common.flags |= AOPOBJ_DATA_VALID;
162 #if defined (_ACPI_ASL_COMPILER) || defined (_ACPI_DUMP_App)
165 * i_aSL Compiler cheats by putting parameter count
168 new_node->owner_id = obj_desc->method.param_count;
170 /* Mark this as a very SPECIAL method */
172 obj_desc->method.method_flags = AML_METHOD_INTERNAL_ONLY;
173 obj_desc->method.implementation = acpi_ut_osi_implementation;
177 case ACPI_TYPE_INTEGER:
179 obj_desc->integer.value =
180 (acpi_integer) ACPI_STRTOUL (val, NULL, 10);
184 case ACPI_TYPE_STRING:
187 * Build an object around the static string
189 obj_desc->string.length = (u32) ACPI_STRLEN (val);
190 obj_desc->string.pointer = val;
191 obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
195 case ACPI_TYPE_MUTEX:
197 obj_desc->mutex.node = new_node;
198 obj_desc->mutex.sync_level = (u8) ACPI_STRTOUL
201 if (ACPI_STRCMP (init_val->name, "_GL_") == 0) {
203 * Create a counting semaphore for the
206 status = acpi_os_create_semaphore (ACPI_NO_UNIT_LIMIT,
207 1, &obj_desc->mutex.semaphore);
208 if (ACPI_FAILURE (status)) {
209 acpi_ut_remove_reference (obj_desc);
210 goto unlock_and_exit;
214 * We just created the mutex for the
215 * global lock, save it
217 acpi_gbl_global_lock_semaphore = obj_desc->mutex.semaphore;
222 status = acpi_os_create_semaphore (1, 1,
223 &obj_desc->mutex.semaphore);
224 if (ACPI_FAILURE (status)) {
225 acpi_ut_remove_reference (obj_desc);
226 goto unlock_and_exit;
234 ACPI_REPORT_ERROR (("Unsupported initial type value %X\n",
236 acpi_ut_remove_reference (obj_desc);
241 /* Store pointer to value descriptor in the Node */
243 status = acpi_ns_attach_object (new_node, obj_desc,
244 ACPI_GET_OBJECT_TYPE (obj_desc));
246 /* Remove local reference to the object */
248 acpi_ut_remove_reference (obj_desc);
254 (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
256 /* Save a handle to "_GPE", it is always present */
258 if (ACPI_SUCCESS (status)) {
259 status = acpi_ns_get_node_by_path ("\\_GPE", NULL, ACPI_NS_NO_UPSEARCH,
260 &acpi_gbl_fadt_gpe_device);
263 return_ACPI_STATUS (status);
267 /*******************************************************************************
269 * FUNCTION: acpi_ns_lookup
271 * PARAMETERS: prefix_node - Search scope if name is not fully qualified
272 * Pathname - Search pathname, in internal format
273 * (as represented in the AML stream)
274 * Type - Type associated with name
275 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
276 * Flags - Flags describing the search restrictions
277 * walk_state - Current state of the walk
278 * return_node - Where the Node is placed (if found
279 * or created successfully)
283 * DESCRIPTION: Find or enter the passed name in the name space.
284 * Log an error if name not found in Exec mode.
286 * MUTEX: Assumes namespace is locked.
288 ******************************************************************************/
292 union acpi_generic_state *scope_info,
294 acpi_object_type type,
295 acpi_interpreter_mode interpreter_mode,
297 struct acpi_walk_state *walk_state,
298 struct acpi_namespace_node **return_node)
301 char *path = pathname;
302 struct acpi_namespace_node *prefix_node;
303 struct acpi_namespace_node *current_node = NULL;
304 struct acpi_namespace_node *this_node = NULL;
307 acpi_name simple_name;
308 acpi_object_type type_to_check_for;
309 acpi_object_type this_search_type;
310 u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
311 u32 local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND |
312 ACPI_NS_SEARCH_PARENT);
315 ACPI_FUNCTION_TRACE ("ns_lookup");
319 return_ACPI_STATUS (AE_BAD_PARAMETER);
322 acpi_gbl_ns_lookup_count++;
323 *return_node = ACPI_ENTRY_NOT_FOUND;
325 if (!acpi_gbl_root_node) {
326 return_ACPI_STATUS (AE_NO_NAMESPACE);
330 * Get the prefix scope.
331 * A null scope means use the root scope
334 (!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;
342 prefix_node = scope_info->scope.node;
343 if (ACPI_GET_DESCRIPTOR_TYPE (prefix_node) != ACPI_DESC_TYPE_NAMED) {
344 ACPI_REPORT_ERROR (("ns_lookup: %p is not a namespace node [%s]\n",
345 prefix_node, acpi_ut_get_descriptor_name (prefix_node)));
346 return_ACPI_STATUS (AE_AML_INTERNAL);
350 * This node might not be a actual "scope" node (such as a
351 * Device/Method, etc.) It could be a Package or other object node.
352 * Backup up the tree to find the containing scope node.
354 while (!acpi_ns_opens_scope (prefix_node->type) &&
355 prefix_node->type != ACPI_TYPE_ANY) {
356 prefix_node = acpi_ns_get_parent_node (prefix_node);
360 /* Save type TBD: may be no longer necessary */
362 type_to_check_for = type;
365 * Begin examination of the actual pathname
368 /* A Null name_path is allowed and refers to the root */
371 this_node = acpi_gbl_root_node;
374 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
375 "Null Pathname (Zero segments), Flags=%X\n", flags));
379 * Name pointer is valid (and must be in internal name format)
381 * Check for scope prefixes:
383 * As represented in the AML stream, a namepath consists of an
384 * optional scope prefix followed by a name segment part.
386 * If present, the scope prefix is either a Root Prefix (in
387 * which case the name is fully qualified), or one or more
388 * Parent Prefixes (in which case the name's scope is relative
389 * to the current scope).
391 if (*path == (u8) AML_ROOT_PREFIX) {
392 /* Pathname is fully qualified, start from the root */
394 this_node = acpi_gbl_root_node;
395 search_parent_flag = ACPI_NS_NO_UPSEARCH;
397 /* Point to name segment part */
401 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
402 "Path is absolute from root [%p]\n", this_node));
405 /* Pathname is relative to current scope, start there */
407 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
408 "Searching relative to prefix scope [%4.4s] (%p)\n",
409 acpi_ut_get_node_name (prefix_node), prefix_node));
412 * Handle multiple Parent Prefixes (carat) by just getting
413 * the parent node for each prefix instance.
415 this_node = prefix_node;
417 while (*path == (u8) AML_PARENT_PREFIX) {
418 /* Name is fully qualified, no search rules apply */
420 search_parent_flag = ACPI_NS_NO_UPSEARCH;
422 * Point past this prefix to the name segment
423 * part or the next Parent Prefix
427 /* Backup to the parent node */
430 this_node = acpi_ns_get_parent_node (this_node);
432 /* Current scope has no parent scope */
435 ("ACPI path has too many parent prefixes (^) - reached beyond root node\n"));
436 return_ACPI_STATUS (AE_NOT_FOUND);
440 if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
441 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
442 "Search scope is [%4.4s], path has %d carat(s)\n",
443 acpi_ut_get_node_name (this_node), num_carats));
448 * Determine the number of ACPI name segments in this pathname.
450 * The segment part consists of either:
451 * - A Null name segment (0)
452 * - A dual_name_prefix followed by two 4-byte name segments
453 * - A multi_name_prefix followed by a byte indicating the
454 * number of segments and the segments themselves.
455 * - A single 4-byte name segment
457 * Examine the name prefix opcode, if any, to determine the number of
463 * Null name after a root or parent prefixes. We already
464 * have the correct target node and there are no name segments.
467 type = this_node->type;
469 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
470 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
474 case AML_DUAL_NAME_PREFIX:
476 /* More than one name_seg, search rules do not apply */
478 search_parent_flag = ACPI_NS_NO_UPSEARCH;
480 /* Two segments, point to first name segment */
485 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
486 "Dual Pathname (2 segments, Flags=%X)\n", flags));
489 case AML_MULTI_NAME_PREFIX_OP:
491 /* More than one name_seg, search rules do not apply */
493 search_parent_flag = ACPI_NS_NO_UPSEARCH;
495 /* Extract segment count, point to first name segment */
498 num_segments = (u32) (u8) *path;
501 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
502 "Multi Pathname (%d Segments, Flags=%X) \n",
503 num_segments, flags));
508 * Not a Null name, no Dual or Multi prefix, hence there is
509 * only one name segment and Pathname is already pointing to it.
513 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
514 "Simple Pathname (1 segment, Flags=%X)\n", flags));
518 ACPI_DEBUG_EXEC (acpi_ns_print_pathname (num_segments, path));
523 * Search namespace for each segment of the name. Loop through and
524 * verify (or add to the namespace) each name segment.
526 * The object type is significant only at the last name
527 * segment. (We don't care about the types along the path, only
528 * the type of the final target object.)
530 this_search_type = ACPI_TYPE_ANY;
531 current_node = this_node;
532 while (num_segments && current_node) {
536 * This is the last segment, enable typechecking
538 this_search_type = type;
541 * Only allow automatic parent search (search rules) if the caller
542 * requested it AND we have a single, non-fully-qualified name_seg
544 if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
545 (flags & ACPI_NS_SEARCH_PARENT)) {
546 local_flags |= ACPI_NS_SEARCH_PARENT;
549 /* Set error flag according to caller */
551 if (flags & ACPI_NS_ERROR_IF_FOUND) {
552 local_flags |= ACPI_NS_ERROR_IF_FOUND;
556 /* Extract one ACPI name from the front of the pathname */
558 ACPI_MOVE_32_TO_32 (&simple_name, path);
560 /* Try to find the single (4 character) ACPI name */
562 status = acpi_ns_search_and_enter (simple_name, walk_state, current_node,
563 interpreter_mode, this_search_type, local_flags, &this_node);
564 if (ACPI_FAILURE (status)) {
565 if (status == AE_NOT_FOUND) {
566 /* Name not found in ACPI namespace */
568 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
569 "Name [%4.4s] not found in scope [%4.4s] %p\n",
570 (char *) &simple_name, (char *) ¤t_node->name,
574 *return_node = this_node;
575 return_ACPI_STATUS (status);
579 * Sanity typecheck of the target object:
581 * If 1) This is the last segment (num_segments == 0)
582 * 2) And we are looking for a specific type
583 * (Not checking for TYPE_ANY)
584 * 3) Which is not an alias
585 * 4) Which is not a local type (TYPE_SCOPE)
586 * 5) And the type of target object is known (not TYPE_ANY)
587 * 6) And target object does not match what we are looking for
589 * Then we have a type mismatch. Just warn and ignore it.
591 if ((num_segments == 0) &&
592 (type_to_check_for != ACPI_TYPE_ANY) &&
593 (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
594 (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) &&
595 (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) &&
596 (this_node->type != ACPI_TYPE_ANY) &&
597 (this_node->type != type_to_check_for)) {
598 /* Complain about a type mismatch */
600 ACPI_REPORT_WARNING (
601 ("ns_lookup: Type mismatch on %4.4s (%s), searching for (%s)\n",
602 (char *) &simple_name, acpi_ut_get_type_name (this_node->type),
603 acpi_ut_get_type_name (type_to_check_for)));
607 * If this is the last name segment and we are not looking for a
608 * specific type, but the type of found object is known, use that type
609 * to see if it opens a scope.
611 if ((num_segments == 0) && (type == ACPI_TYPE_ANY)) {
612 type = this_node->type;
615 /* Point to next name segment and make this node current */
617 path += ACPI_NAME_SIZE;
618 current_node = this_node;
622 * Always check if we need to open a new scope
624 if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
626 * If entry is a type which opens a scope, push the new scope on the
629 if (acpi_ns_opens_scope (type)) {
630 status = acpi_ds_scope_stack_push (this_node, type, walk_state);
631 if (ACPI_FAILURE (status)) {
632 return_ACPI_STATUS (status);
637 *return_node = this_node;
638 return_ACPI_STATUS (AE_OK);