1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: nsutils - Utilities for accessing ACPI namespace, accessing
5 * parents and siblings and Scope manipulation
6 *
7 * Copyright (C) 2000 - 2025, Intel Corp.
8 *
9 *****************************************************************************/
10
11#include <acpi/acpi.h>
12#include "accommon.h"
13#include "acnamesp.h"
14#include "amlcode.h"
15
16#define _COMPONENT ACPI_NAMESPACE
17ACPI_MODULE_NAME("nsutils")
18
19/* Local prototypes */
20#ifdef ACPI_OBSOLETE_FUNCTIONS
21acpi_name acpi_ns_find_parent_name(struct acpi_namespace_node *node_to_search);
22#endif
23
24/*******************************************************************************
25 *
26 * FUNCTION: acpi_ns_print_node_pathname
27 *
28 * PARAMETERS: node - Object
29 * message - Prefix message
30 *
31 * DESCRIPTION: Print an object's full namespace pathname
32 * Manages allocation/freeing of a pathname buffer
33 *
34 ******************************************************************************/
35
36void
37acpi_ns_print_node_pathname(struct acpi_namespace_node *node,
38 const char *message)
39{
40 struct acpi_buffer buffer;
41 acpi_status status;
42
43 if (!node) {
44 acpi_os_printf(format: "[NULL NAME]");
45 return;
46 }
47
48 /* Convert handle to full pathname and print it (with supplied message) */
49
50 buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
51
52 status = acpi_ns_handle_to_pathname(target_handle: node, buffer: &buffer, TRUE);
53 if (ACPI_SUCCESS(status)) {
54 if (message) {
55 acpi_os_printf(format: "%s ", message);
56 }
57
58 acpi_os_printf(format: "%s", (char *)buffer.pointer);
59 ACPI_FREE(buffer.pointer);
60 }
61}
62
63/*******************************************************************************
64 *
65 * FUNCTION: acpi_ns_get_type
66 *
67 * PARAMETERS: node - Parent Node to be examined
68 *
69 * RETURN: Type field from Node whose handle is passed
70 *
71 * DESCRIPTION: Return the type of a Namespace node
72 *
73 ******************************************************************************/
74
75acpi_object_type acpi_ns_get_type(struct acpi_namespace_node * node)
76{
77 ACPI_FUNCTION_TRACE(ns_get_type);
78
79 if (!node) {
80 ACPI_WARNING((AE_INFO, "Null Node parameter"));
81 return_UINT8(ACPI_TYPE_ANY);
82 }
83
84 return_UINT8(node->type);
85}
86
87/*******************************************************************************
88 *
89 * FUNCTION: acpi_ns_local
90 *
91 * PARAMETERS: type - A namespace object type
92 *
93 * RETURN: LOCAL if names must be found locally in objects of the
94 * passed type, 0 if enclosing scopes should be searched
95 *
96 * DESCRIPTION: Returns scope rule for the given object type.
97 *
98 ******************************************************************************/
99
100u32 acpi_ns_local(acpi_object_type type)
101{
102 ACPI_FUNCTION_TRACE(ns_local);
103
104 if (!acpi_ut_valid_object_type(type)) {
105
106 /* Type code out of range */
107
108 ACPI_WARNING((AE_INFO, "Invalid Object Type 0x%X", type));
109 return_UINT32(ACPI_NS_NORMAL);
110 }
111
112 return_UINT32(acpi_gbl_ns_properties[type] & ACPI_NS_LOCAL);
113}
114
115/*******************************************************************************
116 *
117 * FUNCTION: acpi_ns_get_internal_name_length
118 *
119 * PARAMETERS: info - Info struct initialized with the
120 * external name pointer.
121 *
122 * RETURN: None
123 *
124 * DESCRIPTION: Calculate the length of the internal (AML) namestring
125 * corresponding to the external (ASL) namestring.
126 *
127 ******************************************************************************/
128
129void acpi_ns_get_internal_name_length(struct acpi_namestring_info *info)
130{
131 const char *next_external_char;
132 u32 i;
133
134 ACPI_FUNCTION_ENTRY();
135
136 next_external_char = info->external_name;
137 info->num_carats = 0;
138 info->num_segments = 0;
139 info->fully_qualified = FALSE;
140
141 /*
142 * For the internal name, the required length is 4 bytes per segment,
143 * plus 1 each for root_prefix, multi_name_prefix_op, segment count,
144 * trailing null (which is not really needed, but no there's harm in
145 * putting it there)
146 *
147 * strlen() + 1 covers the first name_seg, which has no path separator
148 */
149 if (ACPI_IS_ROOT_PREFIX(*next_external_char)) {
150 info->fully_qualified = TRUE;
151 next_external_char++;
152
153 /* Skip redundant root_prefix, like \\_SB.PCI0.SBRG.EC0 */
154
155 while (ACPI_IS_ROOT_PREFIX(*next_external_char)) {
156 next_external_char++;
157 }
158 } else {
159 /* Handle Carat prefixes */
160
161 while (ACPI_IS_PARENT_PREFIX(*next_external_char)) {
162 info->num_carats++;
163 next_external_char++;
164 }
165 }
166
167 /*
168 * Determine the number of ACPI name "segments" by counting the number of
169 * path separators within the string. Start with one segment since the
170 * segment count is [(# separators) + 1], and zero separators is ok.
171 */
172 if (*next_external_char) {
173 info->num_segments = 1;
174 for (i = 0; next_external_char[i]; i++) {
175 if (ACPI_IS_PATH_SEPARATOR(next_external_char[i])) {
176 info->num_segments++;
177 }
178 }
179 }
180
181 info->length = (ACPI_NAMESEG_SIZE * info->num_segments) +
182 4 + info->num_carats;
183
184 info->next_external_char = next_external_char;
185}
186
187/*******************************************************************************
188 *
189 * FUNCTION: acpi_ns_build_internal_name
190 *
191 * PARAMETERS: info - Info struct fully initialized
192 *
193 * RETURN: Status
194 *
195 * DESCRIPTION: Construct the internal (AML) namestring
196 * corresponding to the external (ASL) namestring.
197 *
198 ******************************************************************************/
199
200acpi_status acpi_ns_build_internal_name(struct acpi_namestring_info *info)
201{
202 u32 num_segments = info->num_segments;
203 char *internal_name = info->internal_name;
204 const char *external_name = info->next_external_char;
205 char *result = NULL;
206 u32 i;
207
208 ACPI_FUNCTION_TRACE(ns_build_internal_name);
209
210 /* Setup the correct prefixes, counts, and pointers */
211
212 if (info->fully_qualified) {
213 internal_name[0] = AML_ROOT_PREFIX;
214
215 if (num_segments <= 1) {
216 result = &internal_name[1];
217 } else if (num_segments == 2) {
218 internal_name[1] = AML_DUAL_NAME_PREFIX;
219 result = &internal_name[2];
220 } else {
221 internal_name[1] = AML_MULTI_NAME_PREFIX;
222 internal_name[2] = (char)num_segments;
223 result = &internal_name[3];
224 }
225 } else {
226 /*
227 * Not fully qualified.
228 * Handle Carats first, then append the name segments
229 */
230 i = 0;
231 if (info->num_carats) {
232 for (i = 0; i < info->num_carats; i++) {
233 internal_name[i] = AML_PARENT_PREFIX;
234 }
235 }
236
237 if (num_segments <= 1) {
238 result = &internal_name[i];
239 } else if (num_segments == 2) {
240 internal_name[i] = AML_DUAL_NAME_PREFIX;
241 result = &internal_name[(acpi_size)i + 1];
242 } else {
243 internal_name[i] = AML_MULTI_NAME_PREFIX;
244 internal_name[(acpi_size)i + 1] = (char)num_segments;
245 result = &internal_name[(acpi_size)i + 2];
246 }
247 }
248
249 /* Build the name (minus path separators) */
250
251 for (; num_segments; num_segments--) {
252 for (i = 0; i < ACPI_NAMESEG_SIZE; i++) {
253 if (ACPI_IS_PATH_SEPARATOR(*external_name) ||
254 (*external_name == 0)) {
255
256 /* Pad the segment with underscore(s) if segment is short */
257
258 result[i] = '_';
259 } else {
260 /* Convert the character to uppercase and save it */
261
262 result[i] = (char)toupper((int)*external_name);
263 external_name++;
264 }
265 }
266
267 /* Now we must have a path separator, or the pathname is bad */
268
269 if (!ACPI_IS_PATH_SEPARATOR(*external_name) &&
270 (*external_name != 0)) {
271 return_ACPI_STATUS(AE_BAD_PATHNAME);
272 }
273
274 /* Move on the next segment */
275
276 external_name++;
277 result += ACPI_NAMESEG_SIZE;
278 }
279
280 /* Terminate the string */
281
282 *result = 0;
283
284 if (info->fully_qualified) {
285 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
286 "Returning [%p] (abs) \"\\%s\"\n",
287 internal_name, internal_name));
288 } else {
289 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Returning [%p] (rel) \"%s\"\n",
290 internal_name, internal_name));
291 }
292
293 return_ACPI_STATUS(AE_OK);
294}
295
296/*******************************************************************************
297 *
298 * FUNCTION: acpi_ns_internalize_name
299 *
300 * PARAMETERS: *external_name - External representation of name
301 * **Converted name - Where to return the resulting
302 * internal represention of the name
303 *
304 * RETURN: Status
305 *
306 * DESCRIPTION: Convert an external representation (e.g. "\_PR_.CPU0")
307 * to internal form (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
308 *
309 *******************************************************************************/
310
311acpi_status
312acpi_ns_internalize_name(const char *external_name, char **converted_name)
313{
314 char *internal_name;
315 struct acpi_namestring_info info;
316 acpi_status status;
317
318 ACPI_FUNCTION_TRACE(ns_internalize_name);
319
320 if ((!external_name) || (*external_name == 0) || (!converted_name)) {
321 return_ACPI_STATUS(AE_BAD_PARAMETER);
322 }
323
324 /* Get the length of the new internal name */
325
326 info.external_name = external_name;
327 acpi_ns_get_internal_name_length(info: &info);
328
329 /* We need a segment to store the internal name */
330
331 internal_name = ACPI_ALLOCATE_ZEROED(info.length);
332 if (!internal_name) {
333 return_ACPI_STATUS(AE_NO_MEMORY);
334 }
335
336 /* Build the name */
337
338 info.internal_name = internal_name;
339 status = acpi_ns_build_internal_name(info: &info);
340 if (ACPI_FAILURE(status)) {
341 ACPI_FREE(internal_name);
342 return_ACPI_STATUS(status);
343 }
344
345 *converted_name = internal_name;
346 return_ACPI_STATUS(AE_OK);
347}
348
349/*******************************************************************************
350 *
351 * FUNCTION: acpi_ns_externalize_name
352 *
353 * PARAMETERS: internal_name_length - Length of the internal name below
354 * internal_name - Internal representation of name
355 * converted_name_length - Where the length is returned
356 * converted_name - Where the resulting external name
357 * is returned
358 *
359 * RETURN: Status
360 *
361 * DESCRIPTION: Convert internal name (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
362 * to its external (printable) form (e.g. "\_PR_.CPU0")
363 *
364 ******************************************************************************/
365
366acpi_status
367acpi_ns_externalize_name(u32 internal_name_length,
368 const char *internal_name,
369 u32 * converted_name_length, char **converted_name)
370{
371 u32 names_index = 0;
372 u32 num_segments = 0;
373 u32 required_length;
374 u32 prefix_length = 0;
375 u32 i = 0;
376 u32 j = 0;
377
378 ACPI_FUNCTION_TRACE(ns_externalize_name);
379
380 if (!internal_name_length || !internal_name || !converted_name) {
381 return_ACPI_STATUS(AE_BAD_PARAMETER);
382 }
383
384 /* Check for a prefix (one '\' | one or more '^') */
385
386 switch (internal_name[0]) {
387 case AML_ROOT_PREFIX:
388
389 prefix_length = 1;
390 break;
391
392 case AML_PARENT_PREFIX:
393
394 for (i = 0; i < internal_name_length; i++) {
395 if (ACPI_IS_PARENT_PREFIX(internal_name[i])) {
396 prefix_length = i + 1;
397 } else {
398 break;
399 }
400 }
401
402 if (i == internal_name_length) {
403 prefix_length = i;
404 }
405
406 break;
407
408 default:
409
410 break;
411 }
412
413 /*
414 * Check for object names. Note that there could be 0-255 of these
415 * 4-byte elements.
416 */
417 if (prefix_length < internal_name_length) {
418 switch (internal_name[prefix_length]) {
419 case AML_MULTI_NAME_PREFIX:
420
421 /* <count> 4-byte names */
422
423 names_index = prefix_length + 2;
424 num_segments = (u8)
425 internal_name[(acpi_size)prefix_length + 1];
426 break;
427
428 case AML_DUAL_NAME_PREFIX:
429
430 /* Two 4-byte names */
431
432 names_index = prefix_length + 1;
433 num_segments = 2;
434 break;
435
436 case 0:
437
438 /* null_name */
439
440 names_index = 0;
441 num_segments = 0;
442 break;
443
444 default:
445
446 /* one 4-byte name */
447
448 names_index = prefix_length;
449 num_segments = 1;
450 break;
451 }
452 }
453
454 /*
455 * Calculate the length of converted_name, which equals the length
456 * of the prefix, length of all object names, length of any required
457 * punctuation ('.') between object names, plus the NULL terminator.
458 */
459 required_length = prefix_length + (4 * num_segments) +
460 ((num_segments > 0) ? (num_segments - 1) : 0) + 1;
461
462 /*
463 * Check to see if we're still in bounds. If not, there's a problem
464 * with internal_name (invalid format).
465 */
466 if (required_length > internal_name_length) {
467 ACPI_ERROR((AE_INFO, "Invalid internal name"));
468 return_ACPI_STATUS(AE_BAD_PATHNAME);
469 }
470
471 /* Build the converted_name */
472
473 *converted_name = ACPI_ALLOCATE_ZEROED(required_length);
474 if (!(*converted_name)) {
475 return_ACPI_STATUS(AE_NO_MEMORY);
476 }
477
478 j = 0;
479
480 for (i = 0; i < prefix_length; i++) {
481 (*converted_name)[j++] = internal_name[i];
482 }
483
484 if (num_segments > 0) {
485 for (i = 0; i < num_segments; i++) {
486 if (i > 0) {
487 (*converted_name)[j++] = '.';
488 }
489
490 /* Copy and validate the 4-char name segment */
491
492 ACPI_COPY_NAMESEG(&(*converted_name)[j],
493 &internal_name[names_index]);
494 acpi_ut_repair_name(name: &(*converted_name)[j]);
495
496 j += ACPI_NAMESEG_SIZE;
497 names_index += ACPI_NAMESEG_SIZE;
498 }
499 }
500
501 if (converted_name_length) {
502 *converted_name_length = (u32) required_length;
503 }
504
505 return_ACPI_STATUS(AE_OK);
506}
507
508/*******************************************************************************
509 *
510 * FUNCTION: acpi_ns_validate_handle
511 *
512 * PARAMETERS: handle - Handle to be validated and typecast to a
513 * namespace node.
514 *
515 * RETURN: A pointer to a namespace node
516 *
517 * DESCRIPTION: Convert a namespace handle to a namespace node. Handles special
518 * cases for the root node.
519 *
520 * NOTE: Real integer handles would allow for more verification
521 * and keep all pointers within this subsystem - however this introduces
522 * more overhead and has not been necessary to this point. Drivers
523 * holding handles are typically notified before a node becomes invalid
524 * due to a table unload.
525 *
526 ******************************************************************************/
527
528struct acpi_namespace_node *acpi_ns_validate_handle(acpi_handle handle)
529{
530
531 ACPI_FUNCTION_ENTRY();
532
533 /* Parameter validation */
534
535 if ((!handle) || (handle == ACPI_ROOT_OBJECT)) {
536 return (acpi_gbl_root_node);
537 }
538
539 /* We can at least attempt to verify the handle */
540
541 if (ACPI_GET_DESCRIPTOR_TYPE(handle) != ACPI_DESC_TYPE_NAMED) {
542 return (NULL);
543 }
544
545 return (ACPI_CAST_PTR(struct acpi_namespace_node, handle));
546}
547
548/*******************************************************************************
549 *
550 * FUNCTION: acpi_ns_terminate
551 *
552 * PARAMETERS: none
553 *
554 * RETURN: none
555 *
556 * DESCRIPTION: free memory allocated for namespace and ACPI table storage.
557 *
558 ******************************************************************************/
559
560void acpi_ns_terminate(void)
561{
562 acpi_status status;
563
564 ACPI_FUNCTION_TRACE(ns_terminate);
565
566 /*
567 * Free the entire namespace -- all nodes and all objects
568 * attached to the nodes
569 */
570 acpi_ns_delete_namespace_subtree(parent_handle: acpi_gbl_root_node);
571
572 /* Delete any objects attached to the root node */
573
574 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
575 if (ACPI_FAILURE(status)) {
576 return_VOID;
577 }
578
579 acpi_ns_delete_node(node: acpi_gbl_root_node);
580 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
581
582 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Namespace freed\n"));
583 return_VOID;
584}
585
586/*******************************************************************************
587 *
588 * FUNCTION: acpi_ns_opens_scope
589 *
590 * PARAMETERS: type - A valid namespace type
591 *
592 * RETURN: NEWSCOPE if the passed type "opens a name scope" according
593 * to the ACPI specification, else 0
594 *
595 ******************************************************************************/
596
597u32 acpi_ns_opens_scope(acpi_object_type type)
598{
599 ACPI_FUNCTION_ENTRY();
600
601 if (type > ACPI_TYPE_LOCAL_MAX) {
602
603 /* type code out of range */
604
605 ACPI_WARNING((AE_INFO, "Invalid Object Type 0x%X", type));
606 return (ACPI_NS_NORMAL);
607 }
608
609 return (((u32)acpi_gbl_ns_properties[type]) & ACPI_NS_NEWSCOPE);
610}
611
612/*******************************************************************************
613 *
614 * FUNCTION: acpi_ns_get_node_unlocked
615 *
616 * PARAMETERS: *pathname - Name to be found, in external (ASL) format. The
617 * \ (backslash) and ^ (carat) prefixes, and the
618 * . (period) to separate segments are supported.
619 * prefix_node - Root of subtree to be searched, or NS_ALL for the
620 * root of the name space. If Name is fully
621 * qualified (first s8 is '\'), the passed value
622 * of Scope will not be accessed.
623 * flags - Used to indicate whether to perform upsearch or
624 * not.
625 * return_node - Where the Node is returned
626 *
627 * DESCRIPTION: Look up a name relative to a given scope and return the
628 * corresponding Node. NOTE: Scope can be null.
629 *
630 * MUTEX: Doesn't locks namespace
631 *
632 ******************************************************************************/
633
634acpi_status
635acpi_ns_get_node_unlocked(struct acpi_namespace_node *prefix_node,
636 const char *pathname,
637 u32 flags, struct acpi_namespace_node **return_node)
638{
639 union acpi_generic_state scope_info;
640 acpi_status status;
641 char *internal_path;
642
643 ACPI_FUNCTION_TRACE_PTR(ns_get_node_unlocked,
644 ACPI_CAST_PTR(char, pathname));
645
646 /* Simplest case is a null pathname */
647
648 if (!pathname) {
649 *return_node = prefix_node;
650 if (!prefix_node) {
651 *return_node = acpi_gbl_root_node;
652 }
653
654 return_ACPI_STATUS(AE_OK);
655 }
656
657 /* Quick check for a reference to the root */
658
659 if (ACPI_IS_ROOT_PREFIX(pathname[0]) && (!pathname[1])) {
660 *return_node = acpi_gbl_root_node;
661 return_ACPI_STATUS(AE_OK);
662 }
663
664 /* Convert path to internal representation */
665
666 status = acpi_ns_internalize_name(external_name: pathname, converted_name: &internal_path);
667 if (ACPI_FAILURE(status)) {
668 return_ACPI_STATUS(status);
669 }
670
671 /* Setup lookup scope (search starting point) */
672
673 scope_info.scope.node = prefix_node;
674
675 /* Lookup the name in the namespace */
676
677 status = acpi_ns_lookup(scope_info: &scope_info, name: internal_path, ACPI_TYPE_ANY,
678 interpreter_mode: ACPI_IMODE_EXECUTE,
679 flags: (flags | ACPI_NS_DONT_OPEN_SCOPE), NULL,
680 ret_node: return_node);
681 if (ACPI_FAILURE(status)) {
682 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s, %s\n",
683 pathname, acpi_format_exception(status)));
684 }
685
686 ACPI_FREE(internal_path);
687 return_ACPI_STATUS(status);
688}
689
690/*******************************************************************************
691 *
692 * FUNCTION: acpi_ns_get_node
693 *
694 * PARAMETERS: *pathname - Name to be found, in external (ASL) format. The
695 * \ (backslash) and ^ (carat) prefixes, and the
696 * . (period) to separate segments are supported.
697 * prefix_node - Root of subtree to be searched, or NS_ALL for the
698 * root of the name space. If Name is fully
699 * qualified (first s8 is '\'), the passed value
700 * of Scope will not be accessed.
701 * flags - Used to indicate whether to perform upsearch or
702 * not.
703 * return_node - Where the Node is returned
704 *
705 * DESCRIPTION: Look up a name relative to a given scope and return the
706 * corresponding Node. NOTE: Scope can be null.
707 *
708 * MUTEX: Locks namespace
709 *
710 ******************************************************************************/
711
712acpi_status
713acpi_ns_get_node(struct acpi_namespace_node *prefix_node,
714 const char *pathname,
715 u32 flags, struct acpi_namespace_node **return_node)
716{
717 acpi_status status;
718
719 ACPI_FUNCTION_TRACE_PTR(ns_get_node, ACPI_CAST_PTR(char, pathname));
720
721 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
722 if (ACPI_FAILURE(status)) {
723 return_ACPI_STATUS(status);
724 }
725
726 status = acpi_ns_get_node_unlocked(prefix_node, pathname,
727 flags, return_node);
728
729 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
730 return_ACPI_STATUS(status);
731}
732