1 /*******************************************************************************
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2007, 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);
201 acpi_os_create_mutex(&obj_desc
->mutex
.
203 if (ACPI_FAILURE(status
)) {
204 acpi_ut_remove_reference(obj_desc
);
205 goto unlock_and_exit
;
208 /* Special case for ACPI Global Lock */
210 if (ACPI_STRCMP(init_val
->name
, "_GL_") == 0) {
211 acpi_gbl_global_lock_mutex
=
212 obj_desc
->mutex
.os_mutex
;
214 /* Create additional counting semaphore for global lock */
217 acpi_os_create_semaphore(1, 0,
218 &acpi_gbl_global_lock_semaphore
);
219 if (ACPI_FAILURE(status
)) {
220 acpi_ut_remove_reference
222 goto unlock_and_exit
;
230 "Unsupported initial type value %X",
232 acpi_ut_remove_reference(obj_desc
);
237 /* Store pointer to value descriptor in the Node */
239 status
= acpi_ns_attach_object(new_node
, obj_desc
,
243 /* Remove local reference to the object */
245 acpi_ut_remove_reference(obj_desc
);
250 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE
);
252 /* Save a handle to "_GPE", it is always present */
254 if (ACPI_SUCCESS(status
)) {
255 status
= acpi_ns_get_node(NULL
, "\\_GPE", ACPI_NS_NO_UPSEARCH
,
256 &acpi_gbl_fadt_gpe_device
);
259 return_ACPI_STATUS(status
);
262 /*******************************************************************************
264 * FUNCTION: acpi_ns_lookup
266 * PARAMETERS: scope_info - Current scope info block
267 * Pathname - Search pathname, in internal format
268 * (as represented in the AML stream)
269 * Type - Type associated with name
270 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
271 * Flags - Flags describing the search restrictions
272 * walk_state - Current state of the walk
273 * return_node - Where the Node is placed (if found
274 * or created successfully)
278 * DESCRIPTION: Find or enter the passed name in the name space.
279 * Log an error if name not found in Exec mode.
281 * MUTEX: Assumes namespace is locked.
283 ******************************************************************************/
286 acpi_ns_lookup(union acpi_generic_state
*scope_info
,
288 acpi_object_type type
,
289 acpi_interpreter_mode interpreter_mode
,
291 struct acpi_walk_state
*walk_state
,
292 struct acpi_namespace_node
**return_node
)
295 char *path
= pathname
;
296 struct acpi_namespace_node
*prefix_node
;
297 struct acpi_namespace_node
*current_node
= NULL
;
298 struct acpi_namespace_node
*this_node
= NULL
;
301 acpi_name simple_name
;
302 acpi_object_type type_to_check_for
;
303 acpi_object_type this_search_type
;
304 u32 search_parent_flag
= ACPI_NS_SEARCH_PARENT
;
307 ACPI_FUNCTION_TRACE(ns_lookup
);
310 return_ACPI_STATUS(AE_BAD_PARAMETER
);
313 local_flags
= flags
& ~(ACPI_NS_ERROR_IF_FOUND
| ACPI_NS_SEARCH_PARENT
);
314 *return_node
= ACPI_ENTRY_NOT_FOUND
;
315 acpi_gbl_ns_lookup_count
++;
317 if (!acpi_gbl_root_node
) {
318 return_ACPI_STATUS(AE_NO_NAMESPACE
);
322 * Get the prefix scope.
323 * A null scope means use the root scope
325 if ((!scope_info
) || (!scope_info
->scope
.node
)) {
326 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
327 "Null scope prefix, using root node (%p)\n",
328 acpi_gbl_root_node
));
330 prefix_node
= acpi_gbl_root_node
;
332 prefix_node
= scope_info
->scope
.node
;
333 if (ACPI_GET_DESCRIPTOR_TYPE(prefix_node
) !=
334 ACPI_DESC_TYPE_NAMED
) {
335 ACPI_ERROR((AE_INFO
, "%p is not a namespace node [%s]",
337 acpi_ut_get_descriptor_name(prefix_node
)));
338 return_ACPI_STATUS(AE_AML_INTERNAL
);
341 if (!(flags
& ACPI_NS_PREFIX_IS_SCOPE
)) {
343 * This node might not be a actual "scope" node (such as a
344 * Device/Method, etc.) It could be a Package or other object node.
345 * Backup up the tree to find the containing scope node.
347 while (!acpi_ns_opens_scope(prefix_node
->type
) &&
348 prefix_node
->type
!= ACPI_TYPE_ANY
) {
350 acpi_ns_get_parent_node(prefix_node
);
355 /* Save type TBD: may be no longer necessary */
357 type_to_check_for
= type
;
360 * Begin examination of the actual pathname
364 /* A Null name_path is allowed and refers to the root */
367 this_node
= acpi_gbl_root_node
;
370 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
371 "Null Pathname (Zero segments), Flags=%X\n",
375 * Name pointer is valid (and must be in internal name format)
377 * Check for scope prefixes:
379 * As represented in the AML stream, a namepath consists of an
380 * optional scope prefix followed by a name segment part.
382 * If present, the scope prefix is either a Root Prefix (in
383 * which case the name is fully qualified), or one or more
384 * Parent Prefixes (in which case the name's scope is relative
385 * to the current scope).
387 if (*path
== (u8
) AML_ROOT_PREFIX
) {
389 /* Pathname is fully qualified, start from the root */
391 this_node
= acpi_gbl_root_node
;
392 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
394 /* Point to name segment part */
398 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
399 "Path is absolute from root [%p]\n",
402 /* Pathname is relative to current scope, start there */
404 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
405 "Searching relative to prefix scope [%4.4s] (%p)\n",
406 acpi_ut_get_node_name(prefix_node
),
410 * Handle multiple Parent Prefixes (carat) by just getting
411 * the parent node for each prefix instance.
413 this_node
= prefix_node
;
415 while (*path
== (u8
) AML_PARENT_PREFIX
) {
417 /* Name is fully qualified, no search rules apply */
419 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
421 * Point past this prefix to the name segment
422 * part or the next Parent Prefix
426 /* Backup to the parent node */
429 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"));
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
444 (this_node
), num_carats
));
449 * Determine the number of ACPI name segments in this pathname.
451 * The segment part consists of either:
452 * - A Null name segment (0)
453 * - A dual_name_prefix followed by two 4-byte name segments
454 * - A multi_name_prefix followed by a byte indicating the
455 * number of segments and the segments themselves.
456 * - A single 4-byte name segment
458 * Examine the name prefix opcode, if any, to determine the number of
464 * Null name after a root or parent prefixes. We already
465 * have the correct target node and there are no name segments.
468 type
= this_node
->type
;
470 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
471 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
475 case AML_DUAL_NAME_PREFIX
:
477 /* More than one name_seg, search rules do not apply */
479 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
481 /* Two segments, point to first name segment */
486 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
487 "Dual Pathname (2 segments, Flags=%X)\n",
491 case AML_MULTI_NAME_PREFIX_OP
:
493 /* More than one name_seg, search rules do not apply */
495 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
497 /* Extract segment count, point to first name segment */
500 num_segments
= (u32
) (u8
) * path
;
503 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
504 "Multi Pathname (%d Segments, Flags=%X)\n",
505 num_segments
, flags
));
510 * Not a Null name, no Dual or Multi prefix, hence there is
511 * only one name segment and Pathname is already pointing to it.
515 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
516 "Simple Pathname (1 segment, Flags=%X)\n",
521 ACPI_DEBUG_EXEC(acpi_ns_print_pathname(num_segments
, path
));
525 * Search namespace for each segment of the name. Loop through and
526 * verify (or add to the namespace) each name segment.
528 * The object type is significant only at the last name
529 * segment. (We don't care about the types along the path, only
530 * the type of the final target object.)
532 this_search_type
= ACPI_TYPE_ANY
;
533 current_node
= this_node
;
534 while (num_segments
&& current_node
) {
538 * This is the last segment, enable typechecking
540 this_search_type
= type
;
543 * Only allow automatic parent search (search rules) if the caller
544 * requested it AND we have a single, non-fully-qualified name_seg
546 if ((search_parent_flag
!= ACPI_NS_NO_UPSEARCH
) &&
547 (flags
& ACPI_NS_SEARCH_PARENT
)) {
548 local_flags
|= ACPI_NS_SEARCH_PARENT
;
551 /* Set error flag according to caller */
553 if (flags
& ACPI_NS_ERROR_IF_FOUND
) {
554 local_flags
|= ACPI_NS_ERROR_IF_FOUND
;
558 /* Extract one ACPI name from the front of the pathname */
560 ACPI_MOVE_32_TO_32(&simple_name
, path
);
562 /* Try to find the single (4 character) ACPI name */
565 acpi_ns_search_and_enter(simple_name
, walk_state
,
566 current_node
, interpreter_mode
,
567 this_search_type
, local_flags
,
569 if (ACPI_FAILURE(status
)) {
570 if (status
== AE_NOT_FOUND
) {
572 /* Name not found in ACPI namespace */
574 ACPI_DEBUG_PRINT((ACPI_DB_NAMES
,
575 "Name [%4.4s] not found in scope [%4.4s] %p\n",
576 (char *)&simple_name
,
577 (char *)¤t_node
->name
,
581 *return_node
= this_node
;
582 return_ACPI_STATUS(status
);
586 * Sanity typecheck of the target object:
588 * If 1) This is the last segment (num_segments == 0)
589 * 2) And we are looking for a specific type
590 * (Not checking for TYPE_ANY)
591 * 3) Which is not an alias
592 * 4) Which is not a local type (TYPE_SCOPE)
593 * 5) And the type of target object is known (not TYPE_ANY)
594 * 6) And target object does not match what we are looking for
596 * Then we have a type mismatch. Just warn and ignore it.
598 if ((num_segments
== 0) &&
599 (type_to_check_for
!= ACPI_TYPE_ANY
) &&
600 (type_to_check_for
!= ACPI_TYPE_LOCAL_ALIAS
) &&
601 (type_to_check_for
!= ACPI_TYPE_LOCAL_METHOD_ALIAS
) &&
602 (type_to_check_for
!= ACPI_TYPE_LOCAL_SCOPE
) &&
603 (this_node
->type
!= ACPI_TYPE_ANY
) &&
604 (this_node
->type
!= type_to_check_for
)) {
606 /* Complain about a type mismatch */
608 ACPI_WARNING((AE_INFO
,
609 "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
610 ACPI_CAST_PTR(char, &simple_name
),
611 acpi_ut_get_type_name(this_node
->type
),
612 acpi_ut_get_type_name
613 (type_to_check_for
)));
617 * If this is the last name segment and we are not looking for a
618 * specific type, but the type of found object is known, use that type
619 * to see if it opens a scope.
621 if ((num_segments
== 0) && (type
== ACPI_TYPE_ANY
)) {
622 type
= this_node
->type
;
625 /* Point to next name segment and make this node current */
627 path
+= ACPI_NAME_SIZE
;
628 current_node
= this_node
;
632 * Always check if we need to open a new scope
634 if (!(flags
& ACPI_NS_DONT_OPEN_SCOPE
) && (walk_state
)) {
636 * If entry is a type which opens a scope, push the new scope on the
639 if (acpi_ns_opens_scope(type
)) {
641 acpi_ds_scope_stack_push(this_node
, type
,
643 if (ACPI_FAILURE(status
)) {
644 return_ACPI_STATUS(status
);
649 *return_node
= this_node
;
650 return_ACPI_STATUS(AE_OK
);