1/******************************************************************************
2 *
3 * Module Name: nsutils - Utilities for accessing ACPI namespace, accessing
4 *                        parents and siblings and Scope manipulation
5 *
6 *****************************************************************************/
7
8/*
9 * Copyright (C) 2000 - 2014, Intel Corp.
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions, and the following disclaimer,
17 *    without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 *    substantially similar to the "NO WARRANTY" disclaimer below
20 *    ("Disclaimer") and any redistribution must be conditioned upon
21 *    including a substantially similar Disclaimer requirement for further
22 *    binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 *    of any contributors may be used to endorse or promote products derived
25 *    from this software without specific prior written permission.
26 *
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
30 *
31 * NO WARRANTY
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
43 */
44
45#include <acpi/acpi.h>
46#include "accommon.h"
47#include "acnamesp.h"
48#include "amlcode.h"
49
50#define _COMPONENT          ACPI_NAMESPACE
51ACPI_MODULE_NAME("nsutils")
52
53/* Local prototypes */
54#ifdef ACPI_OBSOLETE_FUNCTIONS
55acpi_name acpi_ns_find_parent_name(struct acpi_namespace_node *node_to_search);
56#endif
57
58/*******************************************************************************
59 *
60 * FUNCTION:    acpi_ns_print_node_pathname
61 *
62 * PARAMETERS:  node            - Object
63 *              message         - Prefix message
64 *
65 * DESCRIPTION: Print an object's full namespace pathname
66 *              Manages allocation/freeing of a pathname buffer
67 *
68 ******************************************************************************/
69
70void
71acpi_ns_print_node_pathname(struct acpi_namespace_node *node,
72			    const char *message)
73{
74	struct acpi_buffer buffer;
75	acpi_status status;
76
77	if (!node) {
78		acpi_os_printf("[NULL NAME]");
79		return;
80	}
81
82	/* Convert handle to full pathname and print it (with supplied message) */
83
84	buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
85
86	status = acpi_ns_handle_to_pathname(node, &buffer);
87	if (ACPI_SUCCESS(status)) {
88		if (message) {
89			acpi_os_printf("%s ", message);
90		}
91
92		acpi_os_printf("[%s] (Node %p)", (char *)buffer.pointer, node);
93		ACPI_FREE(buffer.pointer);
94	}
95}
96
97/*******************************************************************************
98 *
99 * FUNCTION:    acpi_ns_get_type
100 *
101 * PARAMETERS:  node        - Parent Node to be examined
102 *
103 * RETURN:      Type field from Node whose handle is passed
104 *
105 * DESCRIPTION: Return the type of a Namespace node
106 *
107 ******************************************************************************/
108
109acpi_object_type acpi_ns_get_type(struct acpi_namespace_node * node)
110{
111	ACPI_FUNCTION_TRACE(ns_get_type);
112
113	if (!node) {
114		ACPI_WARNING((AE_INFO, "Null Node parameter"));
115		return_UINT8(ACPI_TYPE_ANY);
116	}
117
118	return_UINT8(node->type);
119}
120
121/*******************************************************************************
122 *
123 * FUNCTION:    acpi_ns_local
124 *
125 * PARAMETERS:  type        - A namespace object type
126 *
127 * RETURN:      LOCAL if names must be found locally in objects of the
128 *              passed type, 0 if enclosing scopes should be searched
129 *
130 * DESCRIPTION: Returns scope rule for the given object type.
131 *
132 ******************************************************************************/
133
134u32 acpi_ns_local(acpi_object_type type)
135{
136	ACPI_FUNCTION_TRACE(ns_local);
137
138	if (!acpi_ut_valid_object_type(type)) {
139
140		/* Type code out of range  */
141
142		ACPI_WARNING((AE_INFO, "Invalid Object Type 0x%X", type));
143		return_UINT32(ACPI_NS_NORMAL);
144	}
145
146	return_UINT32(acpi_gbl_ns_properties[type] & ACPI_NS_LOCAL);
147}
148
149/*******************************************************************************
150 *
151 * FUNCTION:    acpi_ns_get_internal_name_length
152 *
153 * PARAMETERS:  info            - Info struct initialized with the
154 *                                external name pointer.
155 *
156 * RETURN:      None
157 *
158 * DESCRIPTION: Calculate the length of the internal (AML) namestring
159 *              corresponding to the external (ASL) namestring.
160 *
161 ******************************************************************************/
162
163void acpi_ns_get_internal_name_length(struct acpi_namestring_info *info)
164{
165	const char *next_external_char;
166	u32 i;
167
168	ACPI_FUNCTION_ENTRY();
169
170	next_external_char = info->external_name;
171	info->num_carats = 0;
172	info->num_segments = 0;
173	info->fully_qualified = FALSE;
174
175	/*
176	 * For the internal name, the required length is 4 bytes per segment, plus
177	 * 1 each for root_prefix, multi_name_prefix_op, segment count, trailing null
178	 * (which is not really needed, but no there's harm in putting it there)
179	 *
180	 * strlen() + 1 covers the first name_seg, which has no path separator
181	 */
182	if (ACPI_IS_ROOT_PREFIX(*next_external_char)) {
183		info->fully_qualified = TRUE;
184		next_external_char++;
185
186		/* Skip redundant root_prefix, like \\_SB.PCI0.SBRG.EC0 */
187
188		while (ACPI_IS_ROOT_PREFIX(*next_external_char)) {
189			next_external_char++;
190		}
191	} else {
192		/* Handle Carat prefixes */
193
194		while (ACPI_IS_PARENT_PREFIX(*next_external_char)) {
195			info->num_carats++;
196			next_external_char++;
197		}
198	}
199
200	/*
201	 * Determine the number of ACPI name "segments" by counting the number of
202	 * path separators within the string. Start with one segment since the
203	 * segment count is [(# separators) + 1], and zero separators is ok.
204	 */
205	if (*next_external_char) {
206		info->num_segments = 1;
207		for (i = 0; next_external_char[i]; i++) {
208			if (ACPI_IS_PATH_SEPARATOR(next_external_char[i])) {
209				info->num_segments++;
210			}
211		}
212	}
213
214	info->length = (ACPI_NAME_SIZE * info->num_segments) +
215	    4 + info->num_carats;
216
217	info->next_external_char = next_external_char;
218}
219
220/*******************************************************************************
221 *
222 * FUNCTION:    acpi_ns_build_internal_name
223 *
224 * PARAMETERS:  info            - Info struct fully initialized
225 *
226 * RETURN:      Status
227 *
228 * DESCRIPTION: Construct the internal (AML) namestring
229 *              corresponding to the external (ASL) namestring.
230 *
231 ******************************************************************************/
232
233acpi_status acpi_ns_build_internal_name(struct acpi_namestring_info *info)
234{
235	u32 num_segments = info->num_segments;
236	char *internal_name = info->internal_name;
237	const char *external_name = info->next_external_char;
238	char *result = NULL;
239	u32 i;
240
241	ACPI_FUNCTION_TRACE(ns_build_internal_name);
242
243	/* Setup the correct prefixes, counts, and pointers */
244
245	if (info->fully_qualified) {
246		internal_name[0] = AML_ROOT_PREFIX;
247
248		if (num_segments <= 1) {
249			result = &internal_name[1];
250		} else if (num_segments == 2) {
251			internal_name[1] = AML_DUAL_NAME_PREFIX;
252			result = &internal_name[2];
253		} else {
254			internal_name[1] = AML_MULTI_NAME_PREFIX_OP;
255			internal_name[2] = (char)num_segments;
256			result = &internal_name[3];
257		}
258	} else {
259		/*
260		 * Not fully qualified.
261		 * Handle Carats first, then append the name segments
262		 */
263		i = 0;
264		if (info->num_carats) {
265			for (i = 0; i < info->num_carats; i++) {
266				internal_name[i] = AML_PARENT_PREFIX;
267			}
268		}
269
270		if (num_segments <= 1) {
271			result = &internal_name[i];
272		} else if (num_segments == 2) {
273			internal_name[i] = AML_DUAL_NAME_PREFIX;
274			result = &internal_name[(acpi_size) i + 1];
275		} else {
276			internal_name[i] = AML_MULTI_NAME_PREFIX_OP;
277			internal_name[(acpi_size) i + 1] = (char)num_segments;
278			result = &internal_name[(acpi_size) i + 2];
279		}
280	}
281
282	/* Build the name (minus path separators) */
283
284	for (; num_segments; num_segments--) {
285		for (i = 0; i < ACPI_NAME_SIZE; i++) {
286			if (ACPI_IS_PATH_SEPARATOR(*external_name) ||
287			    (*external_name == 0)) {
288
289				/* Pad the segment with underscore(s) if segment is short */
290
291				result[i] = '_';
292			} else {
293				/* Convert the character to uppercase and save it */
294
295				result[i] =
296				    (char)ACPI_TOUPPER((int)*external_name);
297				external_name++;
298			}
299		}
300
301		/* Now we must have a path separator, or the pathname is bad */
302
303		if (!ACPI_IS_PATH_SEPARATOR(*external_name) &&
304		    (*external_name != 0)) {
305			return_ACPI_STATUS(AE_BAD_PATHNAME);
306		}
307
308		/* Move on the next segment */
309
310		external_name++;
311		result += ACPI_NAME_SIZE;
312	}
313
314	/* Terminate the string */
315
316	*result = 0;
317
318	if (info->fully_qualified) {
319		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
320				  "Returning [%p] (abs) \"\\%s\"\n",
321				  internal_name, internal_name));
322	} else {
323		ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Returning [%p] (rel) \"%s\"\n",
324				  internal_name, internal_name));
325	}
326
327	return_ACPI_STATUS(AE_OK);
328}
329
330/*******************************************************************************
331 *
332 * FUNCTION:    acpi_ns_internalize_name
333 *
334 * PARAMETERS:  *external_name          - External representation of name
335 *              **Converted name        - Where to return the resulting
336 *                                        internal represention of the name
337 *
338 * RETURN:      Status
339 *
340 * DESCRIPTION: Convert an external representation (e.g. "\_PR_.CPU0")
341 *              to internal form (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
342 *
343 *******************************************************************************/
344
345acpi_status
346acpi_ns_internalize_name(const char *external_name, char **converted_name)
347{
348	char *internal_name;
349	struct acpi_namestring_info info;
350	acpi_status status;
351
352	ACPI_FUNCTION_TRACE(ns_internalize_name);
353
354	if ((!external_name) || (*external_name == 0) || (!converted_name)) {
355		return_ACPI_STATUS(AE_BAD_PARAMETER);
356	}
357
358	/* Get the length of the new internal name */
359
360	info.external_name = external_name;
361	acpi_ns_get_internal_name_length(&info);
362
363	/* We need a segment to store the internal  name */
364
365	internal_name = ACPI_ALLOCATE_ZEROED(info.length);
366	if (!internal_name) {
367		return_ACPI_STATUS(AE_NO_MEMORY);
368	}
369
370	/* Build the name */
371
372	info.internal_name = internal_name;
373	status = acpi_ns_build_internal_name(&info);
374	if (ACPI_FAILURE(status)) {
375		ACPI_FREE(internal_name);
376		return_ACPI_STATUS(status);
377	}
378
379	*converted_name = internal_name;
380	return_ACPI_STATUS(AE_OK);
381}
382
383/*******************************************************************************
384 *
385 * FUNCTION:    acpi_ns_externalize_name
386 *
387 * PARAMETERS:  internal_name_length - Lenth of the internal name below
388 *              internal_name       - Internal representation of name
389 *              converted_name_length - Where the length is returned
390 *              converted_name      - Where the resulting external name
391 *                                    is returned
392 *
393 * RETURN:      Status
394 *
395 * DESCRIPTION: Convert internal name (e.g. 5c 2f 02 5f 50 52 5f 43 50 55 30)
396 *              to its external (printable) form (e.g. "\_PR_.CPU0")
397 *
398 ******************************************************************************/
399
400acpi_status
401acpi_ns_externalize_name(u32 internal_name_length,
402			 const char *internal_name,
403			 u32 * converted_name_length, char **converted_name)
404{
405	u32 names_index = 0;
406	u32 num_segments = 0;
407	u32 required_length;
408	u32 prefix_length = 0;
409	u32 i = 0;
410	u32 j = 0;
411
412	ACPI_FUNCTION_TRACE(ns_externalize_name);
413
414	if (!internal_name_length || !internal_name || !converted_name) {
415		return_ACPI_STATUS(AE_BAD_PARAMETER);
416	}
417
418	/* Check for a prefix (one '\' | one or more '^') */
419
420	switch (internal_name[0]) {
421	case AML_ROOT_PREFIX:
422
423		prefix_length = 1;
424		break;
425
426	case AML_PARENT_PREFIX:
427
428		for (i = 0; i < internal_name_length; i++) {
429			if (ACPI_IS_PARENT_PREFIX(internal_name[i])) {
430				prefix_length = i + 1;
431			} else {
432				break;
433			}
434		}
435
436		if (i == internal_name_length) {
437			prefix_length = i;
438		}
439
440		break;
441
442	default:
443
444		break;
445	}
446
447	/*
448	 * Check for object names. Note that there could be 0-255 of these
449	 * 4-byte elements.
450	 */
451	if (prefix_length < internal_name_length) {
452		switch (internal_name[prefix_length]) {
453		case AML_MULTI_NAME_PREFIX_OP:
454
455			/* <count> 4-byte names */
456
457			names_index = prefix_length + 2;
458			num_segments = (u8)
459			    internal_name[(acpi_size) prefix_length + 1];
460			break;
461
462		case AML_DUAL_NAME_PREFIX:
463
464			/* Two 4-byte names */
465
466			names_index = prefix_length + 1;
467			num_segments = 2;
468			break;
469
470		case 0:
471
472			/* null_name */
473
474			names_index = 0;
475			num_segments = 0;
476			break;
477
478		default:
479
480			/* one 4-byte name */
481
482			names_index = prefix_length;
483			num_segments = 1;
484			break;
485		}
486	}
487
488	/*
489	 * Calculate the length of converted_name, which equals the length
490	 * of the prefix, length of all object names, length of any required
491	 * punctuation ('.') between object names, plus the NULL terminator.
492	 */
493	required_length = prefix_length + (4 * num_segments) +
494	    ((num_segments > 0) ? (num_segments - 1) : 0) + 1;
495
496	/*
497	 * Check to see if we're still in bounds. If not, there's a problem
498	 * with internal_name (invalid format).
499	 */
500	if (required_length > internal_name_length) {
501		ACPI_ERROR((AE_INFO, "Invalid internal name"));
502		return_ACPI_STATUS(AE_BAD_PATHNAME);
503	}
504
505	/* Build the converted_name */
506
507	*converted_name = ACPI_ALLOCATE_ZEROED(required_length);
508	if (!(*converted_name)) {
509		return_ACPI_STATUS(AE_NO_MEMORY);
510	}
511
512	j = 0;
513
514	for (i = 0; i < prefix_length; i++) {
515		(*converted_name)[j++] = internal_name[i];
516	}
517
518	if (num_segments > 0) {
519		for (i = 0; i < num_segments; i++) {
520			if (i > 0) {
521				(*converted_name)[j++] = '.';
522			}
523
524			/* Copy and validate the 4-char name segment */
525
526			ACPI_MOVE_NAME(&(*converted_name)[j],
527				       &internal_name[names_index]);
528			acpi_ut_repair_name(&(*converted_name)[j]);
529
530			j += ACPI_NAME_SIZE;
531			names_index += ACPI_NAME_SIZE;
532		}
533	}
534
535	if (converted_name_length) {
536		*converted_name_length = (u32) required_length;
537	}
538
539	return_ACPI_STATUS(AE_OK);
540}
541
542/*******************************************************************************
543 *
544 * FUNCTION:    acpi_ns_validate_handle
545 *
546 * PARAMETERS:  handle          - Handle to be validated and typecast to a
547 *                                namespace node.
548 *
549 * RETURN:      A pointer to a namespace node
550 *
551 * DESCRIPTION: Convert a namespace handle to a namespace node. Handles special
552 *              cases for the root node.
553 *
554 * NOTE: Real integer handles would allow for more verification
555 *       and keep all pointers within this subsystem - however this introduces
556 *       more overhead and has not been necessary to this point. Drivers
557 *       holding handles are typically notified before a node becomes invalid
558 *       due to a table unload.
559 *
560 ******************************************************************************/
561
562struct acpi_namespace_node *acpi_ns_validate_handle(acpi_handle handle)
563{
564
565	ACPI_FUNCTION_ENTRY();
566
567	/* Parameter validation */
568
569	if ((!handle) || (handle == ACPI_ROOT_OBJECT)) {
570		return (acpi_gbl_root_node);
571	}
572
573	/* We can at least attempt to verify the handle */
574
575	if (ACPI_GET_DESCRIPTOR_TYPE(handle) != ACPI_DESC_TYPE_NAMED) {
576		return (NULL);
577	}
578
579	return (ACPI_CAST_PTR(struct acpi_namespace_node, handle));
580}
581
582/*******************************************************************************
583 *
584 * FUNCTION:    acpi_ns_terminate
585 *
586 * PARAMETERS:  none
587 *
588 * RETURN:      none
589 *
590 * DESCRIPTION: free memory allocated for namespace and ACPI table storage.
591 *
592 ******************************************************************************/
593
594void acpi_ns_terminate(void)
595{
596	acpi_status status;
597
598	ACPI_FUNCTION_TRACE(ns_terminate);
599
600	/*
601	 * Free the entire namespace -- all nodes and all objects
602	 * attached to the nodes
603	 */
604	acpi_ns_delete_namespace_subtree(acpi_gbl_root_node);
605
606	/* Delete any objects attached to the root node */
607
608	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
609	if (ACPI_FAILURE(status)) {
610		return_VOID;
611	}
612
613	acpi_ns_delete_node(acpi_gbl_root_node);
614	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
615
616	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Namespace freed\n"));
617	return_VOID;
618}
619
620/*******************************************************************************
621 *
622 * FUNCTION:    acpi_ns_opens_scope
623 *
624 * PARAMETERS:  type        - A valid namespace type
625 *
626 * RETURN:      NEWSCOPE if the passed type "opens a name scope" according
627 *              to the ACPI specification, else 0
628 *
629 ******************************************************************************/
630
631u32 acpi_ns_opens_scope(acpi_object_type type)
632{
633	ACPI_FUNCTION_ENTRY();
634
635	if (type > ACPI_TYPE_LOCAL_MAX) {
636
637		/* type code out of range  */
638
639		ACPI_WARNING((AE_INFO, "Invalid Object Type 0x%X", type));
640		return (ACPI_NS_NORMAL);
641	}
642
643	return (((u32)acpi_gbl_ns_properties[type]) & ACPI_NS_NEWSCOPE);
644}
645
646/*******************************************************************************
647 *
648 * FUNCTION:    acpi_ns_get_node
649 *
650 * PARAMETERS:  *pathname   - Name to be found, in external (ASL) format. The
651 *                            \ (backslash) and ^ (carat) prefixes, and the
652 *                            . (period) to separate segments are supported.
653 *              prefix_node  - Root of subtree to be searched, or NS_ALL for the
654 *                            root of the name space. If Name is fully
655 *                            qualified (first s8 is '\'), the passed value
656 *                            of Scope will not be accessed.
657 *              flags       - Used to indicate whether to perform upsearch or
658 *                            not.
659 *              return_node - Where the Node is returned
660 *
661 * DESCRIPTION: Look up a name relative to a given scope and return the
662 *              corresponding Node. NOTE: Scope can be null.
663 *
664 * MUTEX:       Locks namespace
665 *
666 ******************************************************************************/
667
668acpi_status
669acpi_ns_get_node(struct acpi_namespace_node *prefix_node,
670		 const char *pathname,
671		 u32 flags, struct acpi_namespace_node **return_node)
672{
673	union acpi_generic_state scope_info;
674	acpi_status status;
675	char *internal_path;
676
677	ACPI_FUNCTION_TRACE_PTR(ns_get_node, ACPI_CAST_PTR(char, pathname));
678
679	/* Simplest case is a null pathname */
680
681	if (!pathname) {
682		*return_node = prefix_node;
683		if (!prefix_node) {
684			*return_node = acpi_gbl_root_node;
685		}
686		return_ACPI_STATUS(AE_OK);
687	}
688
689	/* Quick check for a reference to the root */
690
691	if (ACPI_IS_ROOT_PREFIX(pathname[0]) && (!pathname[1])) {
692		*return_node = acpi_gbl_root_node;
693		return_ACPI_STATUS(AE_OK);
694	}
695
696	/* Convert path to internal representation */
697
698	status = acpi_ns_internalize_name(pathname, &internal_path);
699	if (ACPI_FAILURE(status)) {
700		return_ACPI_STATUS(status);
701	}
702
703	/* Must lock namespace during lookup */
704
705	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
706	if (ACPI_FAILURE(status)) {
707		goto cleanup;
708	}
709
710	/* Setup lookup scope (search starting point) */
711
712	scope_info.scope.node = prefix_node;
713
714	/* Lookup the name in the namespace */
715
716	status = acpi_ns_lookup(&scope_info, internal_path, ACPI_TYPE_ANY,
717				ACPI_IMODE_EXECUTE,
718				(flags | ACPI_NS_DONT_OPEN_SCOPE), NULL,
719				return_node);
720	if (ACPI_FAILURE(status)) {
721		ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s, %s\n",
722				  pathname, acpi_format_exception(status)));
723	}
724
725	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
726
727cleanup:
728	ACPI_FREE(internal_path);
729	return_ACPI_STATUS(status);
730}
731