1 /*******************************************************************************
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
5 ******************************************************************************/
8 * Copyright (C) 2000 - 2005, 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.
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 (
74 const struct acpi_predefined_names
*init_val
= NULL
;
75 struct acpi_namespace_node
*new_node
;
76 union acpi_operand_object
*obj_desc
;
77 acpi_string val
= NULL
;
80 ACPI_FUNCTION_TRACE ("ns_root_initialize");
83 status
= acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE
);
84 if (ACPI_FAILURE (status
)) {
85 return_ACPI_STATUS (status
);
89 * The global root ptr is initially NULL, so a non-NULL value indicates
90 * that acpi_ns_root_initialize() has already been called; just return.
92 if (acpi_gbl_root_node
) {
98 * Tell the rest of the subsystem that the root is initialized
99 * (This is OK because the namespace is locked)
101 acpi_gbl_root_node
= &acpi_gbl_root_node_struct
;
103 /* Enter the pre-defined names in the name table */
105 ACPI_DEBUG_PRINT ((ACPI_DB_INFO
,
106 "Entering predefined entries into namespace\n"));
108 for (init_val
= acpi_gbl_pre_defined_names
; init_val
->name
; init_val
++) {
109 /* _OSI is optional for now, will be permanent later */
111 if (!ACPI_STRCMP (init_val
->name
, "_OSI") && !acpi_gbl_create_osi_method
) {
115 status
= acpi_ns_lookup (NULL
, init_val
->name
, init_val
->type
,
116 ACPI_IMODE_LOAD_PASS2
, ACPI_NS_NO_UPSEARCH
,
119 if (ACPI_FAILURE (status
) || (!new_node
)) /* Must be on same line for code converter */ {
120 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
121 "Could not create predefined name %s, %s\n",
122 init_val
->name
, acpi_format_exception (status
)));
126 * Name entered successfully.
127 * If entry in pre_defined_names[] specifies an
128 * initial value, create the initial value.
131 status
= acpi_os_predefined_override (init_val
, &val
);
132 if (ACPI_FAILURE (status
)) {
133 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
134 "Could not override predefined %s\n",
143 * Entry requests an initial value, allocate a
146 obj_desc
= acpi_ut_create_internal_object (init_val
->type
);
148 status
= AE_NO_MEMORY
;
149 goto unlock_and_exit
;
153 * Convert value string from table entry to
154 * internal representation. Only types actually
155 * used for initial values are implemented here.
157 switch (init_val
->type
) {
158 case ACPI_TYPE_METHOD
:
159 obj_desc
->method
.param_count
= (u8
) ACPI_TO_INTEGER (val
);
160 obj_desc
->common
.flags
|= AOPOBJ_DATA_VALID
;
162 #if defined (ACPI_ASL_COMPILER)
164 /* save the parameter count for the i_aSL compiler */
166 new_node
->value
= obj_desc
->method
.param_count
;
168 /* Mark this as a very SPECIAL method */
170 obj_desc
->method
.method_flags
= AML_METHOD_INTERNAL_ONLY
;
172 #ifndef ACPI_DUMP_APP
173 obj_desc
->method
.implementation
= acpi_ut_osi_implementation
;
178 case ACPI_TYPE_INTEGER
:
180 obj_desc
->integer
.value
= ACPI_TO_INTEGER (val
);
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_TO_INTEGER (val
) - 1);
200 if (ACPI_STRCMP (init_val
->name
, "_GL_") == 0) {
202 * Create a counting semaphore for the
205 status
= acpi_os_create_semaphore (ACPI_NO_UNIT_LIMIT
,
206 1, &obj_desc
->mutex
.semaphore
);
207 if (ACPI_FAILURE (status
)) {
208 acpi_ut_remove_reference (obj_desc
);
209 goto unlock_and_exit
;
213 * We just created the mutex for the
214 * global lock, save it
216 acpi_gbl_global_lock_semaphore
= obj_desc
->mutex
.semaphore
;
221 status
= acpi_os_create_semaphore (1, 1,
222 &obj_desc
->mutex
.semaphore
);
223 if (ACPI_FAILURE (status
)) {
224 acpi_ut_remove_reference (obj_desc
);
225 goto unlock_and_exit
;
233 ACPI_REPORT_ERROR (("Unsupported initial type value %X\n",
235 acpi_ut_remove_reference (obj_desc
);
240 /* Store pointer to value descriptor in the Node */
242 status
= acpi_ns_attach_object (new_node
, obj_desc
,
243 ACPI_GET_OBJECT_TYPE (obj_desc
));
245 /* Remove local reference to the object */
247 acpi_ut_remove_reference (obj_desc
);
253 (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE
);
255 /* Save a handle to "_GPE", it is always present */
257 if (ACPI_SUCCESS (status
)) {
258 status
= acpi_ns_get_node_by_path ("\\_GPE", NULL
, ACPI_NS_NO_UPSEARCH
,
259 &acpi_gbl_fadt_gpe_device
);
262 return_ACPI_STATUS (status
);
266 /*******************************************************************************
268 * FUNCTION: acpi_ns_lookup
270 * PARAMETERS: scope_info - Current scope info block
271 * Pathname - Search pathname, in internal format
272 * (as represented in the AML stream)
273 * Type - Type associated with name
274 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
275 * Flags - Flags describing the search restrictions
276 * walk_state - Current state of the walk
277 * return_node - Where the Node is placed (if found
278 * or created successfully)
282 * DESCRIPTION: Find or enter the passed name in the name space.
283 * Log an error if name not found in Exec mode.
285 * MUTEX: Assumes namespace is locked.
287 ******************************************************************************/
291 union acpi_generic_state
*scope_info
,
293 acpi_object_type type
,
294 acpi_interpreter_mode interpreter_mode
,
296 struct acpi_walk_state
*walk_state
,
297 struct acpi_namespace_node
**return_node
)
300 char *path
= pathname
;
301 struct acpi_namespace_node
*prefix_node
;
302 struct acpi_namespace_node
*current_node
= NULL
;
303 struct acpi_namespace_node
*this_node
= NULL
;
306 acpi_name simple_name
;
307 acpi_object_type type_to_check_for
;
308 acpi_object_type this_search_type
;
309 u32 search_parent_flag
= ACPI_NS_SEARCH_PARENT
;
310 u32 local_flags
= flags
& ~(ACPI_NS_ERROR_IF_FOUND
|
311 ACPI_NS_SEARCH_PARENT
);
314 ACPI_FUNCTION_TRACE ("ns_lookup");
318 return_ACPI_STATUS (AE_BAD_PARAMETER
);
321 acpi_gbl_ns_lookup_count
++;
322 *return_node
= ACPI_ENTRY_NOT_FOUND
;
324 if (!acpi_gbl_root_node
) {
325 return_ACPI_STATUS (AE_NO_NAMESPACE
);
329 * Get the prefix scope.
330 * A null scope means use the root scope
333 (!scope_info
->scope
.node
)) {
334 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
335 "Null scope prefix, using root node (%p)\n",
336 acpi_gbl_root_node
));
338 prefix_node
= acpi_gbl_root_node
;
341 prefix_node
= scope_info
->scope
.node
;
342 if (ACPI_GET_DESCRIPTOR_TYPE (prefix_node
) != ACPI_DESC_TYPE_NAMED
) {
343 ACPI_REPORT_ERROR (("ns_lookup: %p is not a namespace node [%s]\n",
344 prefix_node
, acpi_ut_get_descriptor_name (prefix_node
)));
345 return_ACPI_STATUS (AE_AML_INTERNAL
);
349 * This node might not be a actual "scope" node (such as a
350 * Device/Method, etc.) It could be a Package or other object node.
351 * Backup up the tree to find the containing scope node.
353 while (!acpi_ns_opens_scope (prefix_node
->type
) &&
354 prefix_node
->type
!= ACPI_TYPE_ANY
) {
355 prefix_node
= acpi_ns_get_parent_node (prefix_node
);
359 /* Save type TBD: may be no longer necessary */
361 type_to_check_for
= type
;
364 * Begin examination of the actual pathname
367 /* A Null name_path is allowed and refers to the root */
370 this_node
= acpi_gbl_root_node
;
373 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
374 "Null Pathname (Zero segments), Flags=%X\n", flags
));
378 * Name pointer is valid (and must be in internal name format)
380 * Check for scope prefixes:
382 * As represented in the AML stream, a namepath consists of an
383 * optional scope prefix followed by a name segment part.
385 * If present, the scope prefix is either a Root Prefix (in
386 * which case the name is fully qualified), or one or more
387 * Parent Prefixes (in which case the name's scope is relative
388 * to the current scope).
390 if (*path
== (u8
) AML_ROOT_PREFIX
) {
391 /* Pathname is fully qualified, start from the root */
393 this_node
= acpi_gbl_root_node
;
394 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
396 /* Point to name segment part */
400 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
401 "Path is absolute from root [%p]\n", this_node
));
404 /* Pathname is relative to current scope, start there */
406 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
407 "Searching relative to prefix scope [%4.4s] (%p)\n",
408 acpi_ut_get_node_name (prefix_node
), prefix_node
));
411 * Handle multiple Parent Prefixes (carat) by just getting
412 * the parent node for each prefix instance.
414 this_node
= prefix_node
;
416 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
);
431 /* Current scope has no parent scope */
434 ("ACPI path has too many parent prefixes (^) - reached beyond root node\n"));
435 return_ACPI_STATUS (AE_NOT_FOUND
);
439 if (search_parent_flag
== ACPI_NS_NO_UPSEARCH
) {
440 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
441 "Search scope is [%4.4s], path has %d carat(s)\n",
442 acpi_ut_get_node_name (this_node
), num_carats
));
447 * Determine the number of ACPI name segments in this pathname.
449 * The segment part consists of either:
450 * - A Null name segment (0)
451 * - A dual_name_prefix followed by two 4-byte name segments
452 * - A multi_name_prefix followed by a byte indicating the
453 * number of segments and the segments themselves.
454 * - A single 4-byte name segment
456 * Examine the name prefix opcode, if any, to determine the number of
462 * Null name after a root or parent prefixes. We already
463 * have the correct target node and there are no name segments.
466 type
= this_node
->type
;
468 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
469 "Prefix-only Pathname (Zero name segments), Flags=%X\n",
473 case AML_DUAL_NAME_PREFIX
:
475 /* More than one name_seg, search rules do not apply */
477 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
479 /* Two segments, point to first name segment */
484 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
485 "Dual Pathname (2 segments, Flags=%X)\n", flags
));
488 case AML_MULTI_NAME_PREFIX_OP
:
490 /* More than one name_seg, search rules do not apply */
492 search_parent_flag
= ACPI_NS_NO_UPSEARCH
;
494 /* Extract segment count, point to first name segment */
497 num_segments
= (u32
) (u8
) *path
;
500 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
501 "Multi Pathname (%d Segments, Flags=%X) \n",
502 num_segments
, flags
));
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.
512 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
513 "Simple Pathname (1 segment, Flags=%X)\n", flags
));
517 ACPI_DEBUG_EXEC (acpi_ns_print_pathname (num_segments
, path
));
522 * Search namespace for each segment of the name. Loop through and
523 * verify (or add to the namespace) each name segment.
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.)
529 this_search_type
= ACPI_TYPE_ANY
;
530 current_node
= this_node
;
531 while (num_segments
&& current_node
) {
535 * This is the last segment, enable typechecking
537 this_search_type
= type
;
540 * Only allow automatic parent search (search rules) if the caller
541 * requested it AND we have a single, non-fully-qualified name_seg
543 if ((search_parent_flag
!= ACPI_NS_NO_UPSEARCH
) &&
544 (flags
& ACPI_NS_SEARCH_PARENT
)) {
545 local_flags
|= ACPI_NS_SEARCH_PARENT
;
548 /* Set error flag according to caller */
550 if (flags
& ACPI_NS_ERROR_IF_FOUND
) {
551 local_flags
|= ACPI_NS_ERROR_IF_FOUND
;
555 /* Extract one ACPI name from the front of the pathname */
557 ACPI_MOVE_32_TO_32 (&simple_name
, path
);
559 /* Try to find the single (4 character) ACPI name */
561 status
= acpi_ns_search_and_enter (simple_name
, walk_state
, current_node
,
562 interpreter_mode
, this_search_type
, local_flags
, &this_node
);
563 if (ACPI_FAILURE (status
)) {
564 if (status
== AE_NOT_FOUND
) {
565 /* Name not found in ACPI namespace */
567 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES
,
568 "Name [%4.4s] not found in scope [%4.4s] %p\n",
569 (char *) &simple_name
, (char *) ¤t_node
->name
,
573 *return_node
= this_node
;
574 return_ACPI_STATUS (status
);
578 * Sanity typecheck of the target object:
580 * If 1) This is the last segment (num_segments == 0)
581 * 2) And we are looking for a specific type
582 * (Not checking for TYPE_ANY)
583 * 3) Which is not an alias
584 * 4) Which is not a local type (TYPE_SCOPE)
585 * 5) And the type of target object is known (not TYPE_ANY)
586 * 6) And target object does not match what we are looking for
588 * Then we have a type mismatch. Just warn and ignore it.
590 if ((num_segments
== 0) &&
591 (type_to_check_for
!= ACPI_TYPE_ANY
) &&
592 (type_to_check_for
!= ACPI_TYPE_LOCAL_ALIAS
) &&
593 (type_to_check_for
!= ACPI_TYPE_LOCAL_METHOD_ALIAS
) &&
594 (type_to_check_for
!= ACPI_TYPE_LOCAL_SCOPE
) &&
595 (this_node
->type
!= ACPI_TYPE_ANY
) &&
596 (this_node
->type
!= type_to_check_for
)) {
597 /* Complain about a type mismatch */
599 ACPI_REPORT_WARNING (
600 ("ns_lookup: Type mismatch on %4.4s (%s), searching for (%s)\n",
601 (char *) &simple_name
, acpi_ut_get_type_name (this_node
->type
),
602 acpi_ut_get_type_name (type_to_check_for
)));
606 * If this is the last name segment and we are not looking for a
607 * specific type, but the type of found object is known, use that type
608 * to see if it opens a scope.
610 if ((num_segments
== 0) && (type
== ACPI_TYPE_ANY
)) {
611 type
= this_node
->type
;
614 /* Point to next name segment and make this node current */
616 path
+= ACPI_NAME_SIZE
;
617 current_node
= this_node
;
621 * Always check if we need to open a new scope
623 if (!(flags
& ACPI_NS_DONT_OPEN_SCOPE
) && (walk_state
)) {
625 * If entry is a type which opens a scope, push the new scope on the
628 if (acpi_ns_opens_scope (type
)) {
629 status
= acpi_ds_scope_stack_push (this_node
, type
, walk_state
);
630 if (ACPI_FAILURE (status
)) {
631 return_ACPI_STATUS (status
);
636 *return_node
= this_node
;
637 return_ACPI_STATUS (AE_OK
);