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v3.1
  1/*******************************************************************************
  2 *
  3 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
  4 *                         ACPI Object evaluation interfaces
  5 *
  6 ******************************************************************************/
  7
  8/*
  9 * Copyright (C) 2000 - 2011, 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 "acinterp.h"
 49
 50#define _COMPONENT          ACPI_NAMESPACE
 51ACPI_MODULE_NAME("nsxfeval")
 52
 53/* Local prototypes */
 54static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
 55
 56/*******************************************************************************
 57 *
 58 * FUNCTION:    acpi_evaluate_object_typed
 59 *
 60 * PARAMETERS:  Handle              - Object handle (optional)
 61 *              Pathname            - Object pathname (optional)
 62 *              external_params     - List of parameters to pass to method,
 63 *                                    terminated by NULL.  May be NULL
 64 *                                    if no parameters are being passed.
 65 *              return_buffer       - Where to put method's return value (if
 66 *                                    any).  If NULL, no value is returned.
 67 *              return_type         - Expected type of return object
 68 *
 69 * RETURN:      Status
 70 *
 71 * DESCRIPTION: Find and evaluate the given object, passing the given
 72 *              parameters if necessary.  One of "Handle" or "Pathname" must
 73 *              be valid (non-null)
 74 *
 75 ******************************************************************************/
 76
 77acpi_status
 78acpi_evaluate_object_typed(acpi_handle handle,
 79			   acpi_string pathname,
 80			   struct acpi_object_list *external_params,
 81			   struct acpi_buffer *return_buffer,
 82			   acpi_object_type return_type)
 83{
 84	acpi_status status;
 85	u8 must_free = FALSE;
 86
 87	ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
 88
 89	/* Return buffer must be valid */
 90
 91	if (!return_buffer) {
 92		return_ACPI_STATUS(AE_BAD_PARAMETER);
 93	}
 94
 95	if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
 96		must_free = TRUE;
 97	}
 98
 99	/* Evaluate the object */
100
101	status =
102	    acpi_evaluate_object(handle, pathname, external_params,
103				 return_buffer);
104	if (ACPI_FAILURE(status)) {
105		return_ACPI_STATUS(status);
106	}
107
108	/* Type ANY means "don't care" */
109
110	if (return_type == ACPI_TYPE_ANY) {
111		return_ACPI_STATUS(AE_OK);
112	}
113
114	if (return_buffer->length == 0) {
115
116		/* Error because caller specifically asked for a return value */
117
118		ACPI_ERROR((AE_INFO, "No return value"));
119		return_ACPI_STATUS(AE_NULL_OBJECT);
120	}
121
122	/* Examine the object type returned from evaluate_object */
123
124	if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
125		return_ACPI_STATUS(AE_OK);
126	}
127
128	/* Return object type does not match requested type */
129
130	ACPI_ERROR((AE_INFO,
131		    "Incorrect return type [%s] requested [%s]",
132		    acpi_ut_get_type_name(((union acpi_object *)return_buffer->
133					   pointer)->type),
134		    acpi_ut_get_type_name(return_type)));
135
136	if (must_free) {
137
138		/* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
139
140		ACPI_FREE(return_buffer->pointer);
 
 
 
 
141		return_buffer->pointer = NULL;
142	}
143
144	return_buffer->length = 0;
145	return_ACPI_STATUS(AE_TYPE);
146}
147
148ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
149
150/*******************************************************************************
151 *
152 * FUNCTION:    acpi_evaluate_object
153 *
154 * PARAMETERS:  Handle              - Object handle (optional)
155 *              Pathname            - Object pathname (optional)
156 *              external_params     - List of parameters to pass to method,
157 *                                    terminated by NULL.  May be NULL
158 *                                    if no parameters are being passed.
159 *              return_buffer       - Where to put method's return value (if
160 *                                    any).  If NULL, no value is returned.
161 *
162 * RETURN:      Status
163 *
164 * DESCRIPTION: Find and evaluate the given object, passing the given
165 *              parameters if necessary.  One of "Handle" or "Pathname" must
166 *              be valid (non-null)
167 *
168 ******************************************************************************/
169acpi_status
170acpi_evaluate_object(acpi_handle handle,
171		     acpi_string pathname,
172		     struct acpi_object_list *external_params,
173		     struct acpi_buffer *return_buffer)
174{
175	acpi_status status;
176	struct acpi_evaluate_info *info;
177	acpi_size buffer_space_needed;
178	u32 i;
179
180	ACPI_FUNCTION_TRACE(acpi_evaluate_object);
181
182	/* Allocate and initialize the evaluation information block */
183
184	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
185	if (!info) {
186		return_ACPI_STATUS(AE_NO_MEMORY);
187	}
188
189	info->pathname = pathname;
190
191	/* Convert and validate the device handle */
192
193	info->prefix_node = acpi_ns_validate_handle(handle);
194	if (!info->prefix_node) {
195		status = AE_BAD_PARAMETER;
196		goto cleanup;
197	}
198
199	/*
200	 * If there are parameters to be passed to a control method, the external
201	 * objects must all be converted to internal objects
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
202	 */
203	if (external_params && external_params->count) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
204		/*
205		 * Allocate a new parameter block for the internal objects
206		 * Add 1 to count to allow for null terminated internal list
207		 */
208		info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
209							 external_params->
210							 count +
211							 1) * sizeof(void *));
212		if (!info->parameters) {
213			status = AE_NO_MEMORY;
214			goto cleanup;
215		}
216
217		/* Convert each external object in the list to an internal object */
218
219		for (i = 0; i < external_params->count; i++) {
220			status =
221			    acpi_ut_copy_eobject_to_iobject(&external_params->
222							    pointer[i],
223							    &info->
224							    parameters[i]);
225			if (ACPI_FAILURE(status)) {
226				goto cleanup;
227			}
228		}
229		info->parameters[external_params->count] = NULL;
 
230	}
231
 
 
232	/*
233	 * Three major cases:
234	 * 1) Fully qualified pathname
235	 * 2) No handle, not fully qualified pathname (error)
236	 * 3) Valid handle
237	 */
238	if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
239
240		/* The path is fully qualified, just evaluate by name */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
241
242		info->prefix_node = NULL;
243		status = acpi_ns_evaluate(info);
244	} else if (!handle) {
245		/*
246		 * A handle is optional iff a fully qualified pathname is specified.
247		 * Since we've already handled fully qualified names above, this is
248		 * an error
249		 */
250		if (!pathname) {
251			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
252					  "Both Handle and Pathname are NULL"));
253		} else {
254			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
255					  "Null Handle with relative pathname [%s]",
256					  pathname));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
257		}
 
258
259		status = AE_BAD_PARAMETER;
260	} else {
261		/* We have a namespace a node and a possible relative path */
262
263		status = acpi_ns_evaluate(info);
 
 
 
 
 
 
 
264	}
265
 
 
 
 
 
 
266	/*
267	 * If we are expecting a return value, and all went well above,
268	 * copy the return value to an external object.
269	 */
270	if (return_buffer) {
271		if (!info->return_object) {
272			return_buffer->length = 0;
273		} else {
274			if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
275			    ACPI_DESC_TYPE_NAMED) {
276				/*
277				 * If we received a NS Node as a return object, this means that
278				 * the object we are evaluating has nothing interesting to
279				 * return (such as a mutex, etc.)  We return an error because
280				 * these types are essentially unsupported by this interface.
281				 * We don't check up front because this makes it easier to add
282				 * support for various types at a later date if necessary.
283				 */
284				status = AE_TYPE;
285				info->return_object = NULL;	/* No need to delete a NS Node */
286				return_buffer->length = 0;
287			}
288
289			if (ACPI_SUCCESS(status)) {
290
291				/* Dereference Index and ref_of references */
292
293				acpi_ns_resolve_references(info);
294
295				/* Get the size of the returned object */
296
297				status =
298				    acpi_ut_get_object_size(info->return_object,
299							    &buffer_space_needed);
300				if (ACPI_SUCCESS(status)) {
301
302					/* Validate/Allocate/Clear caller buffer */
303
304					status =
305					    acpi_ut_initialize_buffer
306					    (return_buffer,
307					     buffer_space_needed);
308					if (ACPI_FAILURE(status)) {
309						/*
310						 * Caller's buffer is too small or a new one can't
311						 * be allocated
312						 */
313						ACPI_DEBUG_PRINT((ACPI_DB_INFO,
314								  "Needed buffer size %X, %s\n",
315								  (u32)
316								  buffer_space_needed,
317								  acpi_format_exception
318								  (status)));
319					} else {
320						/* We have enough space for the object, build it */
321
322						status =
323						    acpi_ut_copy_iobject_to_eobject
324						    (info->return_object,
325						     return_buffer);
326					}
327				}
328			}
329		}
330	}
331
332	if (info->return_object) {
333		/*
334		 * Delete the internal return object. NOTE: Interpreter must be
335		 * locked to avoid race condition.
336		 */
337		acpi_ex_enter_interpreter();
338
339		/* Remove one reference on the return object (should delete it) */
340
341		acpi_ut_remove_reference(info->return_object);
342		acpi_ex_exit_interpreter();
343	}
344
345      cleanup:
346
347	/* Free the input parameter list (if we created one) */
348
349	if (info->parameters) {
350
351		/* Free the allocated parameter block */
352
353		acpi_ut_delete_internal_object_list(info->parameters);
354	}
355
356	ACPI_FREE(info);
357	return_ACPI_STATUS(status);
358}
359
360ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
361
362/*******************************************************************************
363 *
364 * FUNCTION:    acpi_ns_resolve_references
365 *
366 * PARAMETERS:  Info                    - Evaluation info block
367 *
368 * RETURN:      Info->return_object is replaced with the dereferenced object
369 *
370 * DESCRIPTION: Dereference certain reference objects. Called before an
371 *              internal return object is converted to an external union acpi_object.
372 *
373 * Performs an automatic dereference of Index and ref_of reference objects.
374 * These reference objects are not supported by the union acpi_object, so this is a
375 * last resort effort to return something useful. Also, provides compatibility
376 * with other ACPI implementations.
377 *
378 * NOTE: does not handle references within returned package objects or nested
379 * references, but this support could be added later if found to be necessary.
380 *
381 ******************************************************************************/
382static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
383{
384	union acpi_operand_object *obj_desc = NULL;
385	struct acpi_namespace_node *node;
386
387	/* We are interested in reference objects only */
388
389	if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
390		return;
391	}
392
393	/*
394	 * Two types of references are supported - those created by Index and
395	 * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
396	 * to an union acpi_object, so it is not dereferenced here. A ddb_handle
397	 * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
398	 * an union acpi_object.
399	 */
400	switch (info->return_object->reference.class) {
401	case ACPI_REFCLASS_INDEX:
402
403		obj_desc = *(info->return_object->reference.where);
404		break;
405
406	case ACPI_REFCLASS_REFOF:
407
408		node = info->return_object->reference.object;
409		if (node) {
410			obj_desc = node->object;
411		}
412		break;
413
414	default:
 
415		return;
416	}
417
418	/* Replace the existing reference object */
419
420	if (obj_desc) {
421		acpi_ut_add_reference(obj_desc);
422		acpi_ut_remove_reference(info->return_object);
423		info->return_object = obj_desc;
424	}
425
426	return;
427}
428
429/*******************************************************************************
430 *
431 * FUNCTION:    acpi_walk_namespace
432 *
433 * PARAMETERS:  Type                - acpi_object_type to search for
434 *              start_object        - Handle in namespace where search begins
435 *              max_depth           - Depth to which search is to reach
436 *              pre_order_visit     - Called during tree pre-order visit
437 *                                    when an object of "Type" is found
438 *              post_order_visit    - Called during tree post-order visit
439 *                                    when an object of "Type" is found
440 *              Context             - Passed to user function(s) above
441 *              return_value        - Location where return value of
442 *                                    user_function is put if terminated early
443 *
444 * RETURNS      Return value from the user_function if terminated early.
445 *              Otherwise, returns NULL.
446 *
447 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
448 *              starting (and ending) at the object specified by start_handle.
449 *              The callback function is called whenever an object that matches
450 *              the type parameter is found. If the callback function returns
451 *              a non-zero value, the search is terminated immediately and this
452 *              value is returned to the caller.
453 *
454 *              The point of this procedure is to provide a generic namespace
455 *              walk routine that can be called from multiple places to
456 *              provide multiple services; the callback function(s) can be
457 *              tailored to each task, whether it is a print function,
458 *              a compare function, etc.
459 *
460 ******************************************************************************/
461
462acpi_status
463acpi_walk_namespace(acpi_object_type type,
464		    acpi_handle start_object,
465		    u32 max_depth,
466		    acpi_walk_callback pre_order_visit,
467		    acpi_walk_callback post_order_visit,
468		    void *context, void **return_value)
469{
470	acpi_status status;
471
472	ACPI_FUNCTION_TRACE(acpi_walk_namespace);
473
474	/* Parameter validation */
475
476	if ((type > ACPI_TYPE_LOCAL_MAX) ||
477	    (!max_depth) || (!pre_order_visit && !post_order_visit)) {
478		return_ACPI_STATUS(AE_BAD_PARAMETER);
479	}
480
481	/*
482	 * Need to acquire the namespace reader lock to prevent interference
483	 * with any concurrent table unloads (which causes the deletion of
484	 * namespace objects). We cannot allow the deletion of a namespace node
485	 * while the user function is using it. The exception to this are the
486	 * nodes created and deleted during control method execution -- these
487	 * nodes are marked as temporary nodes and are ignored by the namespace
488	 * walk. Thus, control methods can be executed while holding the
489	 * namespace deletion lock (and the user function can execute control
490	 * methods.)
491	 */
492	status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
493	if (ACPI_FAILURE(status)) {
494		return status;
495	}
496
497	/*
498	 * Lock the namespace around the walk. The namespace will be
499	 * unlocked/locked around each call to the user function - since the user
500	 * function must be allowed to make ACPICA calls itself (for example, it
501	 * will typically execute control methods during device enumeration.)
502	 */
503	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
504	if (ACPI_FAILURE(status)) {
505		goto unlock_and_exit;
506	}
507
 
 
 
 
 
 
 
508	status = acpi_ns_walk_namespace(type, start_object, max_depth,
509					ACPI_NS_WALK_UNLOCK, pre_order_visit,
510					post_order_visit, context,
511					return_value);
512
 
513	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
514
515      unlock_and_exit:
516	(void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
517	return_ACPI_STATUS(status);
518}
519
520ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
521
522/*******************************************************************************
523 *
524 * FUNCTION:    acpi_ns_get_device_callback
525 *
526 * PARAMETERS:  Callback from acpi_get_device
527 *
528 * RETURN:      Status
529 *
530 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
531 *              present devices, or if they specified a HID, it filters based
532 *              on that.
533 *
534 ******************************************************************************/
535static acpi_status
536acpi_ns_get_device_callback(acpi_handle obj_handle,
537			    u32 nesting_level,
538			    void *context, void **return_value)
539{
540	struct acpi_get_devices_info *info = context;
541	acpi_status status;
542	struct acpi_namespace_node *node;
543	u32 flags;
544	struct acpica_device_id *hid;
545	struct acpica_device_id_list *cid;
546	u32 i;
547	u8 found;
548	int no_match;
549
550	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
551	if (ACPI_FAILURE(status)) {
552		return (status);
553	}
554
555	node = acpi_ns_validate_handle(obj_handle);
556	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
557	if (ACPI_FAILURE(status)) {
558		return (status);
559	}
560
561	if (!node) {
562		return (AE_BAD_PARAMETER);
563	}
564
565	/*
566	 * First, filter based on the device HID and CID.
567	 *
568	 * 01/2010: For this case where a specific HID is requested, we don't
569	 * want to run _STA until we have an actual HID match. Thus, we will
570	 * not unnecessarily execute _STA on devices for which the caller
571	 * doesn't care about. Previously, _STA was executed unconditionally
572	 * on all devices found here.
573	 *
574	 * A side-effect of this change is that now we will continue to search
575	 * for a matching HID even under device trees where the parent device
576	 * would have returned a _STA that indicates it is not present or
577	 * not functioning (thus aborting the search on that branch).
578	 */
579	if (info->hid != NULL) {
580		status = acpi_ut_execute_HID(node, &hid);
581		if (status == AE_NOT_FOUND) {
582			return (AE_OK);
583		} else if (ACPI_FAILURE(status)) {
584			return (AE_CTRL_DEPTH);
585		}
586
587		no_match = ACPI_STRCMP(hid->string, info->hid);
588		ACPI_FREE(hid);
589
590		if (no_match) {
591			/*
592			 * HID does not match, attempt match within the
593			 * list of Compatible IDs (CIDs)
594			 */
595			status = acpi_ut_execute_CID(node, &cid);
596			if (status == AE_NOT_FOUND) {
597				return (AE_OK);
598			} else if (ACPI_FAILURE(status)) {
599				return (AE_CTRL_DEPTH);
600			}
601
602			/* Walk the CID list */
603
604			found = 0;
605			for (i = 0; i < cid->count; i++) {
606				if (ACPI_STRCMP(cid->ids[i].string, info->hid)
607				    == 0) {
608					found = 1;
 
 
609					break;
610				}
611			}
 
612			ACPI_FREE(cid);
613			if (!found)
614				return (AE_OK);
 
615		}
616	}
617
618	/* Run _STA to determine if device is present */
619
620	status = acpi_ut_execute_STA(node, &flags);
621	if (ACPI_FAILURE(status)) {
622		return (AE_CTRL_DEPTH);
623	}
624
625	if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
626	    !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
627		/*
628		 * Don't examine the children of the device only when the
629		 * device is neither present nor functional. See ACPI spec,
630		 * description of _STA for more information.
631		 */
632		return (AE_CTRL_DEPTH);
633	}
634
635	/* We have a valid device, invoke the user function */
636
637	status = info->user_function(obj_handle, nesting_level, info->context,
638				     return_value);
639	return (status);
640}
641
642/*******************************************************************************
643 *
644 * FUNCTION:    acpi_get_devices
645 *
646 * PARAMETERS:  HID                 - HID to search for. Can be NULL.
647 *              user_function       - Called when a matching object is found
648 *              Context             - Passed to user function
649 *              return_value        - Location where return value of
650 *                                    user_function is put if terminated early
651 *
652 * RETURNS      Return value from the user_function if terminated early.
653 *              Otherwise, returns NULL.
654 *
655 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
656 *              starting (and ending) at the object specified by start_handle.
657 *              The user_function is called whenever an object of type
658 *              Device is found.  If the user function returns
659 *              a non-zero value, the search is terminated immediately and this
660 *              value is returned to the caller.
661 *
662 *              This is a wrapper for walk_namespace, but the callback performs
663 *              additional filtering. Please see acpi_ns_get_device_callback.
664 *
665 ******************************************************************************/
666
667acpi_status
668acpi_get_devices(const char *HID,
669		 acpi_walk_callback user_function,
670		 void *context, void **return_value)
671{
672	acpi_status status;
673	struct acpi_get_devices_info info;
674
675	ACPI_FUNCTION_TRACE(acpi_get_devices);
676
677	/* Parameter validation */
678
679	if (!user_function) {
680		return_ACPI_STATUS(AE_BAD_PARAMETER);
681	}
682
683	/*
684	 * We're going to call their callback from OUR callback, so we need
685	 * to know what it is, and their context parameter.
686	 */
687	info.hid = HID;
688	info.context = context;
689	info.user_function = user_function;
690
691	/*
692	 * Lock the namespace around the walk.
693	 * The namespace will be unlocked/locked around each call
694	 * to the user function - since this function
695	 * must be allowed to make Acpi calls itself.
696	 */
697	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
698	if (ACPI_FAILURE(status)) {
699		return_ACPI_STATUS(status);
700	}
701
702	status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
703					ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
704					acpi_ns_get_device_callback, NULL,
705					&info, return_value);
706
707	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
708	return_ACPI_STATUS(status);
709}
710
711ACPI_EXPORT_SYMBOL(acpi_get_devices)
712
713/*******************************************************************************
714 *
715 * FUNCTION:    acpi_attach_data
716 *
717 * PARAMETERS:  obj_handle          - Namespace node
718 *              Handler             - Handler for this attachment
719 *              Data                - Pointer to data to be attached
720 *
721 * RETURN:      Status
722 *
723 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
724 *
725 ******************************************************************************/
726acpi_status
727acpi_attach_data(acpi_handle obj_handle,
728		 acpi_object_handler handler, void *data)
729{
730	struct acpi_namespace_node *node;
731	acpi_status status;
732
733	/* Parameter validation */
734
735	if (!obj_handle || !handler || !data) {
736		return (AE_BAD_PARAMETER);
737	}
738
739	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
740	if (ACPI_FAILURE(status)) {
741		return (status);
742	}
743
744	/* Convert and validate the handle */
745
746	node = acpi_ns_validate_handle(obj_handle);
747	if (!node) {
748		status = AE_BAD_PARAMETER;
749		goto unlock_and_exit;
750	}
751
752	status = acpi_ns_attach_data(node, handler, data);
753
754      unlock_and_exit:
755	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
756	return (status);
757}
758
759ACPI_EXPORT_SYMBOL(acpi_attach_data)
760
761/*******************************************************************************
762 *
763 * FUNCTION:    acpi_detach_data
764 *
765 * PARAMETERS:  obj_handle          - Namespace node handle
766 *              Handler             - Handler used in call to acpi_attach_data
767 *
768 * RETURN:      Status
769 *
770 * DESCRIPTION: Remove data that was previously attached to a node.
771 *
772 ******************************************************************************/
773acpi_status
774acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
775{
776	struct acpi_namespace_node *node;
777	acpi_status status;
778
779	/* Parameter validation */
780
781	if (!obj_handle || !handler) {
782		return (AE_BAD_PARAMETER);
783	}
784
785	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
786	if (ACPI_FAILURE(status)) {
787		return (status);
788	}
789
790	/* Convert and validate the handle */
791
792	node = acpi_ns_validate_handle(obj_handle);
793	if (!node) {
794		status = AE_BAD_PARAMETER;
795		goto unlock_and_exit;
796	}
797
798	status = acpi_ns_detach_data(node, handler);
799
800      unlock_and_exit:
801	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
802	return (status);
803}
804
805ACPI_EXPORT_SYMBOL(acpi_detach_data)
806
807/*******************************************************************************
808 *
809 * FUNCTION:    acpi_get_data
810 *
811 * PARAMETERS:  obj_handle          - Namespace node
812 *              Handler             - Handler used in call to attach_data
813 *              Data                - Where the data is returned
 
814 *
815 * RETURN:      Status
816 *
817 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 
818 *
819 ******************************************************************************/
820acpi_status
821acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 
822{
823	struct acpi_namespace_node *node;
824	acpi_status status;
825
826	/* Parameter validation */
827
828	if (!obj_handle || !handler || !data) {
829		return (AE_BAD_PARAMETER);
830	}
831
832	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
833	if (ACPI_FAILURE(status)) {
834		return (status);
835	}
836
837	/* Convert and validate the handle */
838
839	node = acpi_ns_validate_handle(obj_handle);
840	if (!node) {
841		status = AE_BAD_PARAMETER;
842		goto unlock_and_exit;
843	}
844
845	status = acpi_ns_get_attached_data(node, handler, data);
 
 
 
846
847      unlock_and_exit:
848	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
849	return (status);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
850}
851
852ACPI_EXPORT_SYMBOL(acpi_get_data)
v4.6
  1/*******************************************************************************
  2 *
  3 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
  4 *                         ACPI Object evaluation interfaces
  5 *
  6 ******************************************************************************/
  7
  8/*
  9 * Copyright (C) 2000 - 2016, 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#define EXPORT_ACPI_INTERFACES
 46
 47#include <acpi/acpi.h>
 48#include "accommon.h"
 49#include "acnamesp.h"
 50#include "acinterp.h"
 51
 52#define _COMPONENT          ACPI_NAMESPACE
 53ACPI_MODULE_NAME("nsxfeval")
 54
 55/* Local prototypes */
 56static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
 57
 58/*******************************************************************************
 59 *
 60 * FUNCTION:    acpi_evaluate_object_typed
 61 *
 62 * PARAMETERS:  handle              - Object handle (optional)
 63 *              pathname            - Object pathname (optional)
 64 *              external_params     - List of parameters to pass to method,
 65 *                                    terminated by NULL. May be NULL
 66 *                                    if no parameters are being passed.
 67 *              return_buffer       - Where to put method's return value (if
 68 *                                    any). If NULL, no value is returned.
 69 *              return_type         - Expected type of return object
 70 *
 71 * RETURN:      Status
 72 *
 73 * DESCRIPTION: Find and evaluate the given object, passing the given
 74 *              parameters if necessary. One of "Handle" or "Pathname" must
 75 *              be valid (non-null)
 76 *
 77 ******************************************************************************/
 78
 79acpi_status
 80acpi_evaluate_object_typed(acpi_handle handle,
 81			   acpi_string pathname,
 82			   struct acpi_object_list *external_params,
 83			   struct acpi_buffer *return_buffer,
 84			   acpi_object_type return_type)
 85{
 86	acpi_status status;
 87	u8 free_buffer_on_error = FALSE;
 88
 89	ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
 90
 91	/* Return buffer must be valid */
 92
 93	if (!return_buffer) {
 94		return_ACPI_STATUS(AE_BAD_PARAMETER);
 95	}
 96
 97	if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
 98		free_buffer_on_error = TRUE;
 99	}
100
101	/* Evaluate the object */
102
103	status = acpi_evaluate_object(handle, pathname,
104				      external_params, return_buffer);
 
105	if (ACPI_FAILURE(status)) {
106		return_ACPI_STATUS(status);
107	}
108
109	/* Type ANY means "don't care" */
110
111	if (return_type == ACPI_TYPE_ANY) {
112		return_ACPI_STATUS(AE_OK);
113	}
114
115	if (return_buffer->length == 0) {
116
117		/* Error because caller specifically asked for a return value */
118
119		ACPI_ERROR((AE_INFO, "No return value"));
120		return_ACPI_STATUS(AE_NULL_OBJECT);
121	}
122
123	/* Examine the object type returned from evaluate_object */
124
125	if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
126		return_ACPI_STATUS(AE_OK);
127	}
128
129	/* Return object type does not match requested type */
130
131	ACPI_ERROR((AE_INFO,
132		    "Incorrect return type [%s] requested [%s]",
133		    acpi_ut_get_type_name(((union acpi_object *)return_buffer->
134					   pointer)->type),
135		    acpi_ut_get_type_name(return_type)));
136
137	if (free_buffer_on_error) {
138		/*
139		 * Free a buffer created via ACPI_ALLOCATE_BUFFER.
140		 * Note: We use acpi_os_free here because acpi_os_allocate was used
141		 * to allocate the buffer. This purposefully bypasses the
142		 * (optionally enabled) allocation tracking mechanism since we
143		 * only want to track internal allocations.
144		 */
145		acpi_os_free(return_buffer->pointer);
146		return_buffer->pointer = NULL;
147	}
148
149	return_buffer->length = 0;
150	return_ACPI_STATUS(AE_TYPE);
151}
152
153ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
154
155/*******************************************************************************
156 *
157 * FUNCTION:    acpi_evaluate_object
158 *
159 * PARAMETERS:  handle              - Object handle (optional)
160 *              pathname            - Object pathname (optional)
161 *              external_params     - List of parameters to pass to method,
162 *                                    terminated by NULL. May be NULL
163 *                                    if no parameters are being passed.
164 *              return_buffer       - Where to put method's return value (if
165 *                                    any). If NULL, no value is returned.
166 *
167 * RETURN:      Status
168 *
169 * DESCRIPTION: Find and evaluate the given object, passing the given
170 *              parameters if necessary. One of "Handle" or "Pathname" must
171 *              be valid (non-null)
172 *
173 ******************************************************************************/
174acpi_status
175acpi_evaluate_object(acpi_handle handle,
176		     acpi_string pathname,
177		     struct acpi_object_list *external_params,
178		     struct acpi_buffer *return_buffer)
179{
180	acpi_status status;
181	struct acpi_evaluate_info *info;
182	acpi_size buffer_space_needed;
183	u32 i;
184
185	ACPI_FUNCTION_TRACE(acpi_evaluate_object);
186
187	/* Allocate and initialize the evaluation information block */
188
189	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
190	if (!info) {
191		return_ACPI_STATUS(AE_NO_MEMORY);
192	}
193
 
 
194	/* Convert and validate the device handle */
195
196	info->prefix_node = acpi_ns_validate_handle(handle);
197	if (!info->prefix_node) {
198		status = AE_BAD_PARAMETER;
199		goto cleanup;
200	}
201
202	/*
203	 * Get the actual namespace node for the target object.
204	 * Handles these cases:
205	 *
206	 * 1) Null node, valid pathname from root (absolute path)
207	 * 2) Node and valid pathname (path relative to Node)
208	 * 3) Node, Null pathname
209	 */
210	if ((pathname) && (ACPI_IS_ROOT_PREFIX(pathname[0]))) {
211
212		/* The path is fully qualified, just evaluate by name */
213
214		info->prefix_node = NULL;
215	} else if (!handle) {
216		/*
217		 * A handle is optional iff a fully qualified pathname is specified.
218		 * Since we've already handled fully qualified names above, this is
219		 * an error.
220		 */
221		if (!pathname) {
222			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
223					  "Both Handle and Pathname are NULL"));
224		} else {
225			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
226					  "Null Handle with relative pathname [%s]",
227					  pathname));
228		}
229
230		status = AE_BAD_PARAMETER;
231		goto cleanup;
232	}
233
234	info->relative_pathname = pathname;
235
236	/*
237	 * Convert all external objects passed as arguments to the
238	 * internal version(s).
239	 */
240	if (external_params && external_params->count) {
241		info->param_count = (u16)external_params->count;
242
243		/* Warn on impossible argument count */
244
245		if (info->param_count > ACPI_METHOD_NUM_ARGS) {
246			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
247					      ACPI_WARN_ALWAYS,
248					      "Excess arguments (%u) - using only %u",
249					      info->param_count,
250					      ACPI_METHOD_NUM_ARGS));
251
252			info->param_count = ACPI_METHOD_NUM_ARGS;
253		}
254
255		/*
256		 * Allocate a new parameter block for the internal objects
257		 * Add 1 to count to allow for null terminated internal list
258		 */
259		info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size) info->
260							 param_count +
 
261							 1) * sizeof(void *));
262		if (!info->parameters) {
263			status = AE_NO_MEMORY;
264			goto cleanup;
265		}
266
267		/* Convert each external object in the list to an internal object */
268
269		for (i = 0; i < info->param_count; i++) {
270			status =
271			    acpi_ut_copy_eobject_to_iobject(&external_params->
272							    pointer[i],
273							    &info->
274							    parameters[i]);
275			if (ACPI_FAILURE(status)) {
276				goto cleanup;
277			}
278		}
279
280		info->parameters[info->param_count] = NULL;
281	}
282
283#if 0
284
285	/*
286	 * Begin incoming argument count analysis. Check for too few args
287	 * and too many args.
 
 
288	 */
 
289
290	switch (acpi_ns_get_type(info->node)) {
291	case ACPI_TYPE_METHOD:
292
293		/* Check incoming argument count against the method definition */
294
295		if (info->obj_desc->method.param_count > info->param_count) {
296			ACPI_ERROR((AE_INFO,
297				    "Insufficient arguments (%u) - %u are required",
298				    info->param_count,
299				    info->obj_desc->method.param_count));
300
301			status = AE_MISSING_ARGUMENTS;
302			goto cleanup;
303		}
304
305		else if (info->obj_desc->method.param_count < info->param_count) {
306			ACPI_WARNING((AE_INFO,
307				      "Excess arguments (%u) - only %u are required",
308				      info->param_count,
309				      info->obj_desc->method.param_count));
310
311			/* Just pass the required number of arguments */
312
313			info->param_count = info->obj_desc->method.param_count;
314		}
315
 
 
 
316		/*
317		 * Any incoming external objects to be passed as arguments to the
318		 * method must be converted to internal objects
 
319		 */
320		if (info->param_count) {
321			/*
322			 * Allocate a new parameter block for the internal objects
323			 * Add 1 to count to allow for null terminated internal list
324			 */
325			info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
326								 info->
327								 param_count +
328								 1) *
329								sizeof(void *));
330			if (!info->parameters) {
331				status = AE_NO_MEMORY;
332				goto cleanup;
333			}
334
335			/* Convert each external object in the list to an internal object */
336
337			for (i = 0; i < info->param_count; i++) {
338				status =
339				    acpi_ut_copy_eobject_to_iobject
340				    (&external_params->pointer[i],
341				     &info->parameters[i]);
342				if (ACPI_FAILURE(status)) {
343					goto cleanup;
344				}
345			}
346
347			info->parameters[info->param_count] = NULL;
348		}
349		break;
350
351	default:
 
 
352
353		/* Warn if arguments passed to an object that is not a method */
354
355		if (info->param_count) {
356			ACPI_WARNING((AE_INFO,
357				      "%u arguments were passed to a non-method ACPI object",
358				      info->param_count));
359		}
360		break;
361	}
362
363#endif
364
365	/* Now we can evaluate the object */
366
367	status = acpi_ns_evaluate(info);
368
369	/*
370	 * If we are expecting a return value, and all went well above,
371	 * copy the return value to an external object.
372	 */
373	if (return_buffer) {
374		if (!info->return_object) {
375			return_buffer->length = 0;
376		} else {
377			if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
378			    ACPI_DESC_TYPE_NAMED) {
379				/*
380				 * If we received a NS Node as a return object, this means that
381				 * the object we are evaluating has nothing interesting to
382				 * return (such as a mutex, etc.)  We return an error because
383				 * these types are essentially unsupported by this interface.
384				 * We don't check up front because this makes it easier to add
385				 * support for various types at a later date if necessary.
386				 */
387				status = AE_TYPE;
388				info->return_object = NULL;	/* No need to delete a NS Node */
389				return_buffer->length = 0;
390			}
391
392			if (ACPI_SUCCESS(status)) {
393
394				/* Dereference Index and ref_of references */
395
396				acpi_ns_resolve_references(info);
397
398				/* Get the size of the returned object */
399
400				status =
401				    acpi_ut_get_object_size(info->return_object,
402							    &buffer_space_needed);
403				if (ACPI_SUCCESS(status)) {
404
405					/* Validate/Allocate/Clear caller buffer */
406
407					status =
408					    acpi_ut_initialize_buffer
409					    (return_buffer,
410					     buffer_space_needed);
411					if (ACPI_FAILURE(status)) {
412						/*
413						 * Caller's buffer is too small or a new one can't
414						 * be allocated
415						 */
416						ACPI_DEBUG_PRINT((ACPI_DB_INFO,
417								  "Needed buffer size %X, %s\n",
418								  (u32)
419								  buffer_space_needed,
420								  acpi_format_exception
421								  (status)));
422					} else {
423						/* We have enough space for the object, build it */
424
425						status =
426						    acpi_ut_copy_iobject_to_eobject
427						    (info->return_object,
428						     return_buffer);
429					}
430				}
431			}
432		}
433	}
434
435	if (info->return_object) {
436		/*
437		 * Delete the internal return object. NOTE: Interpreter must be
438		 * locked to avoid race condition.
439		 */
440		acpi_ex_enter_interpreter();
441
442		/* Remove one reference on the return object (should delete it) */
443
444		acpi_ut_remove_reference(info->return_object);
445		acpi_ex_exit_interpreter();
446	}
447
448cleanup:
449
450	/* Free the input parameter list (if we created one) */
451
452	if (info->parameters) {
453
454		/* Free the allocated parameter block */
455
456		acpi_ut_delete_internal_object_list(info->parameters);
457	}
458
459	ACPI_FREE(info);
460	return_ACPI_STATUS(status);
461}
462
463ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
464
465/*******************************************************************************
466 *
467 * FUNCTION:    acpi_ns_resolve_references
468 *
469 * PARAMETERS:  info                    - Evaluation info block
470 *
471 * RETURN:      Info->return_object is replaced with the dereferenced object
472 *
473 * DESCRIPTION: Dereference certain reference objects. Called before an
474 *              internal return object is converted to an external union acpi_object.
475 *
476 * Performs an automatic dereference of Index and ref_of reference objects.
477 * These reference objects are not supported by the union acpi_object, so this is a
478 * last resort effort to return something useful. Also, provides compatibility
479 * with other ACPI implementations.
480 *
481 * NOTE: does not handle references within returned package objects or nested
482 * references, but this support could be added later if found to be necessary.
483 *
484 ******************************************************************************/
485static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
486{
487	union acpi_operand_object *obj_desc = NULL;
488	struct acpi_namespace_node *node;
489
490	/* We are interested in reference objects only */
491
492	if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
493		return;
494	}
495
496	/*
497	 * Two types of references are supported - those created by Index and
498	 * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
499	 * to an union acpi_object, so it is not dereferenced here. A ddb_handle
500	 * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
501	 * an union acpi_object.
502	 */
503	switch (info->return_object->reference.class) {
504	case ACPI_REFCLASS_INDEX:
505
506		obj_desc = *(info->return_object->reference.where);
507		break;
508
509	case ACPI_REFCLASS_REFOF:
510
511		node = info->return_object->reference.object;
512		if (node) {
513			obj_desc = node->object;
514		}
515		break;
516
517	default:
518
519		return;
520	}
521
522	/* Replace the existing reference object */
523
524	if (obj_desc) {
525		acpi_ut_add_reference(obj_desc);
526		acpi_ut_remove_reference(info->return_object);
527		info->return_object = obj_desc;
528	}
529
530	return;
531}
532
533/*******************************************************************************
534 *
535 * FUNCTION:    acpi_walk_namespace
536 *
537 * PARAMETERS:  type                - acpi_object_type to search for
538 *              start_object        - Handle in namespace where search begins
539 *              max_depth           - Depth to which search is to reach
540 *              descending_callback - Called during tree descent
541 *                                    when an object of "Type" is found
542 *              ascending_callback  - Called during tree ascent
543 *                                    when an object of "Type" is found
544 *              context             - Passed to user function(s) above
545 *              return_value        - Location where return value of
546 *                                    user_function is put if terminated early
547 *
548 * RETURNS      Return value from the user_function if terminated early.
549 *              Otherwise, returns NULL.
550 *
551 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
552 *              starting (and ending) at the object specified by start_handle.
553 *              The callback function is called whenever an object that matches
554 *              the type parameter is found. If the callback function returns
555 *              a non-zero value, the search is terminated immediately and this
556 *              value is returned to the caller.
557 *
558 *              The point of this procedure is to provide a generic namespace
559 *              walk routine that can be called from multiple places to
560 *              provide multiple services; the callback function(s) can be
561 *              tailored to each task, whether it is a print function,
562 *              a compare function, etc.
563 *
564 ******************************************************************************/
565
566acpi_status
567acpi_walk_namespace(acpi_object_type type,
568		    acpi_handle start_object,
569		    u32 max_depth,
570		    acpi_walk_callback descending_callback,
571		    acpi_walk_callback ascending_callback,
572		    void *context, void **return_value)
573{
574	acpi_status status;
575
576	ACPI_FUNCTION_TRACE(acpi_walk_namespace);
577
578	/* Parameter validation */
579
580	if ((type > ACPI_TYPE_LOCAL_MAX) ||
581	    (!max_depth) || (!descending_callback && !ascending_callback)) {
582		return_ACPI_STATUS(AE_BAD_PARAMETER);
583	}
584
585	/*
586	 * Need to acquire the namespace reader lock to prevent interference
587	 * with any concurrent table unloads (which causes the deletion of
588	 * namespace objects). We cannot allow the deletion of a namespace node
589	 * while the user function is using it. The exception to this are the
590	 * nodes created and deleted during control method execution -- these
591	 * nodes are marked as temporary nodes and are ignored by the namespace
592	 * walk. Thus, control methods can be executed while holding the
593	 * namespace deletion lock (and the user function can execute control
594	 * methods.)
595	 */
596	status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
597	if (ACPI_FAILURE(status)) {
598		return_ACPI_STATUS(status);
599	}
600
601	/*
602	 * Lock the namespace around the walk. The namespace will be
603	 * unlocked/locked around each call to the user function - since the user
604	 * function must be allowed to make ACPICA calls itself (for example, it
605	 * will typically execute control methods during device enumeration.)
606	 */
607	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
608	if (ACPI_FAILURE(status)) {
609		goto unlock_and_exit;
610	}
611
612	/* Now we can validate the starting node */
613
614	if (!acpi_ns_validate_handle(start_object)) {
615		status = AE_BAD_PARAMETER;
616		goto unlock_and_exit2;
617	}
618
619	status = acpi_ns_walk_namespace(type, start_object, max_depth,
620					ACPI_NS_WALK_UNLOCK,
621					descending_callback, ascending_callback,
622					context, return_value);
623
624unlock_and_exit2:
625	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
626
627unlock_and_exit:
628	(void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
629	return_ACPI_STATUS(status);
630}
631
632ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
633
634/*******************************************************************************
635 *
636 * FUNCTION:    acpi_ns_get_device_callback
637 *
638 * PARAMETERS:  Callback from acpi_get_device
639 *
640 * RETURN:      Status
641 *
642 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
643 *              present devices, or if they specified a HID, it filters based
644 *              on that.
645 *
646 ******************************************************************************/
647static acpi_status
648acpi_ns_get_device_callback(acpi_handle obj_handle,
649			    u32 nesting_level,
650			    void *context, void **return_value)
651{
652	struct acpi_get_devices_info *info = context;
653	acpi_status status;
654	struct acpi_namespace_node *node;
655	u32 flags;
656	struct acpi_pnp_device_id *hid;
657	struct acpi_pnp_device_id_list *cid;
658	u32 i;
659	u8 found;
660	int no_match;
661
662	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
663	if (ACPI_FAILURE(status)) {
664		return (status);
665	}
666
667	node = acpi_ns_validate_handle(obj_handle);
668	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
669	if (ACPI_FAILURE(status)) {
670		return (status);
671	}
672
673	if (!node) {
674		return (AE_BAD_PARAMETER);
675	}
676
677	/*
678	 * First, filter based on the device HID and CID.
679	 *
680	 * 01/2010: For this case where a specific HID is requested, we don't
681	 * want to run _STA until we have an actual HID match. Thus, we will
682	 * not unnecessarily execute _STA on devices for which the caller
683	 * doesn't care about. Previously, _STA was executed unconditionally
684	 * on all devices found here.
685	 *
686	 * A side-effect of this change is that now we will continue to search
687	 * for a matching HID even under device trees where the parent device
688	 * would have returned a _STA that indicates it is not present or
689	 * not functioning (thus aborting the search on that branch).
690	 */
691	if (info->hid != NULL) {
692		status = acpi_ut_execute_HID(node, &hid);
693		if (status == AE_NOT_FOUND) {
694			return (AE_OK);
695		} else if (ACPI_FAILURE(status)) {
696			return (AE_CTRL_DEPTH);
697		}
698
699		no_match = strcmp(hid->string, info->hid);
700		ACPI_FREE(hid);
701
702		if (no_match) {
703			/*
704			 * HID does not match, attempt match within the
705			 * list of Compatible IDs (CIDs)
706			 */
707			status = acpi_ut_execute_CID(node, &cid);
708			if (status == AE_NOT_FOUND) {
709				return (AE_OK);
710			} else if (ACPI_FAILURE(status)) {
711				return (AE_CTRL_DEPTH);
712			}
713
714			/* Walk the CID list */
715
716			found = FALSE;
717			for (i = 0; i < cid->count; i++) {
718				if (strcmp(cid->ids[i].string, info->hid) == 0) {
719
720					/* Found a matching CID */
721
722					found = TRUE;
723					break;
724				}
725			}
726
727			ACPI_FREE(cid);
728			if (!found) {
729				return (AE_OK);
730			}
731		}
732	}
733
734	/* Run _STA to determine if device is present */
735
736	status = acpi_ut_execute_STA(node, &flags);
737	if (ACPI_FAILURE(status)) {
738		return (AE_CTRL_DEPTH);
739	}
740
741	if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
742	    !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
743		/*
744		 * Don't examine the children of the device only when the
745		 * device is neither present nor functional. See ACPI spec,
746		 * description of _STA for more information.
747		 */
748		return (AE_CTRL_DEPTH);
749	}
750
751	/* We have a valid device, invoke the user function */
752
753	status = info->user_function(obj_handle, nesting_level,
754				     info->context, return_value);
755	return (status);
756}
757
758/*******************************************************************************
759 *
760 * FUNCTION:    acpi_get_devices
761 *
762 * PARAMETERS:  HID                 - HID to search for. Can be NULL.
763 *              user_function       - Called when a matching object is found
764 *              context             - Passed to user function
765 *              return_value        - Location where return value of
766 *                                    user_function is put if terminated early
767 *
768 * RETURNS      Return value from the user_function if terminated early.
769 *              Otherwise, returns NULL.
770 *
771 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
772 *              starting (and ending) at the object specified by start_handle.
773 *              The user_function is called whenever an object of type
774 *              Device is found. If the user function returns
775 *              a non-zero value, the search is terminated immediately and this
776 *              value is returned to the caller.
777 *
778 *              This is a wrapper for walk_namespace, but the callback performs
779 *              additional filtering. Please see acpi_ns_get_device_callback.
780 *
781 ******************************************************************************/
782
783acpi_status
784acpi_get_devices(const char *HID,
785		 acpi_walk_callback user_function,
786		 void *context, void **return_value)
787{
788	acpi_status status;
789	struct acpi_get_devices_info info;
790
791	ACPI_FUNCTION_TRACE(acpi_get_devices);
792
793	/* Parameter validation */
794
795	if (!user_function) {
796		return_ACPI_STATUS(AE_BAD_PARAMETER);
797	}
798
799	/*
800	 * We're going to call their callback from OUR callback, so we need
801	 * to know what it is, and their context parameter.
802	 */
803	info.hid = HID;
804	info.context = context;
805	info.user_function = user_function;
806
807	/*
808	 * Lock the namespace around the walk.
809	 * The namespace will be unlocked/locked around each call
810	 * to the user function - since this function
811	 * must be allowed to make Acpi calls itself.
812	 */
813	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
814	if (ACPI_FAILURE(status)) {
815		return_ACPI_STATUS(status);
816	}
817
818	status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
819					ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
820					acpi_ns_get_device_callback, NULL,
821					&info, return_value);
822
823	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
824	return_ACPI_STATUS(status);
825}
826
827ACPI_EXPORT_SYMBOL(acpi_get_devices)
828
829/*******************************************************************************
830 *
831 * FUNCTION:    acpi_attach_data
832 *
833 * PARAMETERS:  obj_handle          - Namespace node
834 *              handler             - Handler for this attachment
835 *              data                - Pointer to data to be attached
836 *
837 * RETURN:      Status
838 *
839 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
840 *
841 ******************************************************************************/
842acpi_status
843acpi_attach_data(acpi_handle obj_handle,
844		 acpi_object_handler handler, void *data)
845{
846	struct acpi_namespace_node *node;
847	acpi_status status;
848
849	/* Parameter validation */
850
851	if (!obj_handle || !handler || !data) {
852		return (AE_BAD_PARAMETER);
853	}
854
855	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
856	if (ACPI_FAILURE(status)) {
857		return (status);
858	}
859
860	/* Convert and validate the handle */
861
862	node = acpi_ns_validate_handle(obj_handle);
863	if (!node) {
864		status = AE_BAD_PARAMETER;
865		goto unlock_and_exit;
866	}
867
868	status = acpi_ns_attach_data(node, handler, data);
869
870unlock_and_exit:
871	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
872	return (status);
873}
874
875ACPI_EXPORT_SYMBOL(acpi_attach_data)
876
877/*******************************************************************************
878 *
879 * FUNCTION:    acpi_detach_data
880 *
881 * PARAMETERS:  obj_handle          - Namespace node handle
882 *              handler             - Handler used in call to acpi_attach_data
883 *
884 * RETURN:      Status
885 *
886 * DESCRIPTION: Remove data that was previously attached to a node.
887 *
888 ******************************************************************************/
889acpi_status
890acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
891{
892	struct acpi_namespace_node *node;
893	acpi_status status;
894
895	/* Parameter validation */
896
897	if (!obj_handle || !handler) {
898		return (AE_BAD_PARAMETER);
899	}
900
901	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
902	if (ACPI_FAILURE(status)) {
903		return (status);
904	}
905
906	/* Convert and validate the handle */
907
908	node = acpi_ns_validate_handle(obj_handle);
909	if (!node) {
910		status = AE_BAD_PARAMETER;
911		goto unlock_and_exit;
912	}
913
914	status = acpi_ns_detach_data(node, handler);
915
916unlock_and_exit:
917	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
918	return (status);
919}
920
921ACPI_EXPORT_SYMBOL(acpi_detach_data)
922
923/*******************************************************************************
924 *
925 * FUNCTION:    acpi_get_data_full
926 *
927 * PARAMETERS:  obj_handle          - Namespace node
928 *              handler             - Handler used in call to attach_data
929 *              data                - Where the data is returned
930 *              callback            - function to execute before returning
931 *
932 * RETURN:      Status
933 *
934 * DESCRIPTION: Retrieve data that was previously attached to a namespace node
935 *              and execute a callback before returning.
936 *
937 ******************************************************************************/
938acpi_status
939acpi_get_data_full(acpi_handle obj_handle, acpi_object_handler handler,
940		   void **data, void (*callback)(void *))
941{
942	struct acpi_namespace_node *node;
943	acpi_status status;
944
945	/* Parameter validation */
946
947	if (!obj_handle || !handler || !data) {
948		return (AE_BAD_PARAMETER);
949	}
950
951	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
952	if (ACPI_FAILURE(status)) {
953		return (status);
954	}
955
956	/* Convert and validate the handle */
957
958	node = acpi_ns_validate_handle(obj_handle);
959	if (!node) {
960		status = AE_BAD_PARAMETER;
961		goto unlock_and_exit;
962	}
963
964	status = acpi_ns_get_attached_data(node, handler, data);
965	if (ACPI_SUCCESS(status) && callback) {
966		callback(*data);
967	}
968
969unlock_and_exit:
970	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
971	return (status);
972}
973
974ACPI_EXPORT_SYMBOL(acpi_get_data_full)
975
976/*******************************************************************************
977 *
978 * FUNCTION:    acpi_get_data
979 *
980 * PARAMETERS:  obj_handle          - Namespace node
981 *              handler             - Handler used in call to attach_data
982 *              data                - Where the data is returned
983 *
984 * RETURN:      Status
985 *
986 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
987 *
988 ******************************************************************************/
989acpi_status
990acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
991{
992	return acpi_get_data_full(obj_handle, handler, data, NULL);
993}
994
995ACPI_EXPORT_SYMBOL(acpi_get_data)