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
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.
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
;
316 ACPI_FUNCTION_TRACE(ns_lookup
);
319 return_ACPI_STATUS(AE_BAD_PARAMETER
);
322 local_flags
= flags
& ~(ACPI_NS_ERROR_IF_FOUND
| ACPI_NS_SEARCH_PARENT
);
323 *return_node
= ACPI_ENTRY_NOT_FOUND
;
324 acpi_gbl_ns_lookup_count
++;
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
);
350 if (!(flags
& ACPI_NS_PREFIX_IS_SCOPE
)) {
352 * This node might not be a actual "scope" node (such as a
353 * Device/Method, etc.) It could be a Package or other object node.
354 * Backup up the tree to find the containing scope node.
356 while (!acpi_ns_opens_scope(prefix_node
->type
) &&
357 prefix_node
->type
!= ACPI_TYPE_ANY
) {
359 acpi_ns_get_parent_node(prefix_node
);
364 /* Save type TBD: may be no longer necessary */
366 type_to_check_for
= type
;
369 * Begin examination of the actual pathname
373 /* A Null name_path is allowed and refers to the root */
376 this_node
= acpi_gbl_root_node
;
379 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
380 "Null Pathname (Zero segments), Flags=%X\n",
384 * Name pointer is valid (and must be in internal name format)
386 * Check for scope prefixes:
388 * As represented in the AML stream, a namepath consists of an
389 * optional scope prefix followed by a name segment part.
391 * If present, the scope prefix is either a Root Prefix (in
392 * which case the name is fully qualified), or one or more
393 * Parent Prefixes (in which case the name's scope is relative
394 * to the current scope).
396 if (*path
== (u8
) AML_ROOT_PREFIX
) {
398 /* Pathname is fully qualified, start from the root */
400 this_node
= acpi_gbl_root_node
;
401 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
403 /* Point to name segment part */
407 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
408 "Path is absolute from root [%p]\n",
411 /* Pathname is relative to current scope, start there */
413 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
414 "Searching relative to prefix scope [%4.4s] (%p)\n",
415 acpi_ut_get_node_name(prefix_node
),
419 * Handle multiple Parent Prefixes (carat) by just getting
420 * the parent node for each prefix instance.
422 this_node
= prefix_node
;
424 while (*path
== (u8
) AML_PARENT_PREFIX
) {
426 /* Name is fully qualified, no search rules apply */
428 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
430 * Point past this prefix to the name segment
431 * part or the next Parent Prefix
435 /* Backup to the parent node */
438 this_node
= acpi_ns_get_parent_node(this_node
);
441 /* Current scope has no parent scope */
444 "ACPI path has too many parent prefixes (^) - reached beyond root node"));
445 return_ACPI_STATUS(AE_NOT_FOUND
);
449 if (search_parent_flag
== ACPI_NS_NO_UPSEARCH
) {
450 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
451 "Search scope is [%4.4s], path has %d carat(s)\n",
452 acpi_ut_get_node_name
453 (this_node
), num_carats
));
458 * Determine the number of ACPI name segments in this pathname.
460 * The segment part consists of either:
461 * - A Null name segment (0)
462 * - A dual_name_prefix followed by two 4-byte name segments
463 * - A multi_name_prefix followed by a byte indicating the
464 * number of segments and the segments themselves.
465 * - A single 4-byte name segment
467 * Examine the name prefix opcode, if any, to determine the number of
473 * Null name after a root or parent prefixes. We already
474 * have the correct target node and there are no name segments.
477 type
= this_node
->type
;
479 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
480 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
484 case AML_DUAL_NAME_PREFIX
:
486 /* More than one name_seg, search rules do not apply */
488 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
490 /* Two segments, point to first name segment */
495 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
496 "Dual Pathname (2 segments, Flags=%X)\n",
500 case AML_MULTI_NAME_PREFIX_OP
:
502 /* More than one name_seg, search rules do not apply */
504 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
506 /* Extract segment count, point to first name segment */
509 num_segments
= (u32
) (u8
) * path
;
512 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
513 "Multi Pathname (%d Segments, Flags=%X)\n",
514 num_segments
, flags
));
519 * Not a Null name, no Dual or Multi prefix, hence there is
520 * only one name segment and Pathname is already pointing to it.
524 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
525 "Simple Pathname (1 segment, Flags=%X)\n",
530 ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments
, path
));
534 * Search namespace for each segment of the name. Loop through and
535 * verify (or add to the namespace) each name segment.
537 * The object type is significant only at the last name
538 * segment. (We don't care about the types along the path, only
539 * the type of the final target object.)
541 this_search_type
= ACPI_TYPE_ANY
;
542 current_node
= this_node
;
543 while (num_segments
&& current_node
) {
547 * This is the last segment, enable typechecking
549 this_search_type
= type
;
552 * Only allow automatic parent search (search rules) if the caller
553 * requested it AND we have a single, non-fully-qualified name_seg
555 if ((search_parent_flag
!= ACPI_NS_NO_UPSEARCH
) &&
556 (flags
& ACPI_NS_SEARCH_PARENT
)) {
557 local_flags
|= ACPI_NS_SEARCH_PARENT
;
560 /* Set error flag according to caller */
562 if (flags
& ACPI_NS_ERROR_IF_FOUND
) {
563 local_flags
|= ACPI_NS_ERROR_IF_FOUND
;
567 /* Extract one ACPI name from the front of the pathname */
569 ACPI_MOVE_32_TO_32(&simple_name
, path
);
571 /* Try to find the single (4 character) ACPI name */
574 acpi_ns_search_and_enter(simple_name
, walk_state
,
575 current_node
, interpreter_mode
,
576 this_search_type
, local_flags
,
578 if (ACPI_FAILURE(status
)) {
579 if (status
== AE_NOT_FOUND
) {
581 /* Name not found in ACPI namespace */
583 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
584 "Name [%4.4s] not found in scope [%4.4s] %p\n",
585 (char *)&simple_name
,
586 (char *)¤t_node
->name
,
590 *return_node
= this_node
;
591 return_ACPI_STATUS(status
);
595 * Sanity typecheck of the target object:
597 * If 1) This is the last segment (num_segments == 0)
598 * 2) And we are looking for a specific type
599 * (Not checking for TYPE_ANY)
600 * 3) Which is not an alias
601 * 4) Which is not a local type (TYPE_SCOPE)
602 * 5) And the type of target object is known (not TYPE_ANY)
603 * 6) And target object does not match what we are looking for
605 * Then we have a type mismatch. Just warn and ignore it.
607 if ((num_segments
== 0) &&
608 (type_to_check_for
!= ACPI_TYPE_ANY
) &&
609 (type_to_check_for
!= ACPI_TYPE_LOCAL_ALIAS
) &&
610 (type_to_check_for
!= ACPI_TYPE_LOCAL_METHOD_ALIAS
) &&
611 (type_to_check_for
!= ACPI_TYPE_LOCAL_SCOPE
) &&
612 (this_node
->type
!= ACPI_TYPE_ANY
) &&
613 (this_node
->type
!= type_to_check_for
)) {
615 /* Complain about a type mismatch */
617 ACPI_WARNING((AE_INFO
,
618 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
619 ACPI_CAST_PTR(char, &simple_name
),
620 acpi_ut_get_type_name(this_node
->type
),
621 acpi_ut_get_type_name
622 (type_to_check_for
)));
626 * If this is the last name segment and we are not looking for a
627 * specific type, but the type of found object is known, use that type
628 * to see if it opens a scope.
630 if ((num_segments
== 0) && (type
== ACPI_TYPE_ANY
)) {
631 type
= this_node
->type
;
634 /* Point to next name segment and make this node current */
636 path
+= ACPI_NAME_SIZE
;
637 current_node
= this_node
;
641 * Always check if we need to open a new scope
643 if (!(flags
& ACPI_NS_DONT_OPEN_SCOPE
) && (walk_state
)) {
645 * If entry is a type which opens a scope, push the new scope on the
648 if (acpi_ns_opens_scope(type
)) {
650 acpi_ds_scope_stack_push(this_node
, type
,
652 if (ACPI_FAILURE(status
)) {
653 return_ACPI_STATUS(status
);
658 *return_node
= this_node
;
659 return_ACPI_STATUS(AE_OK
);