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v3.5.6
 
  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 - 2012, 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 <linux/export.h>
 46#include <acpi/acpi.h>
 47#include "accommon.h"
 48#include "acnamesp.h"
 49#include "acinterp.h"
 50
 51#define _COMPONENT          ACPI_NAMESPACE
 52ACPI_MODULE_NAME("nsxfeval")
 53
 54/* Local prototypes */
 55static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
 56
 57/*******************************************************************************
 58 *
 59 * FUNCTION:    acpi_evaluate_object_typed
 60 *
 61 * PARAMETERS:  Handle              - Object handle (optional)
 62 *              Pathname            - Object pathname (optional)
 63 *              external_params     - List of parameters to pass to method,
 64 *                                    terminated by NULL.  May be NULL
 65 *                                    if no parameters are being passed.
 66 *              return_buffer       - Where to put method's return value (if
 67 *                                    any).  If NULL, no value is returned.
 68 *              return_type         - Expected type of return object
 69 *
 70 * RETURN:      Status
 71 *
 72 * DESCRIPTION: Find and evaluate the given object, passing the given
 73 *              parameters if necessary.  One of "Handle" or "Pathname" must
 74 *              be valid (non-null)
 75 *
 76 ******************************************************************************/
 77
 78acpi_status
 79acpi_evaluate_object_typed(acpi_handle handle,
 80			   acpi_string pathname,
 81			   struct acpi_object_list *external_params,
 82			   struct acpi_buffer *return_buffer,
 83			   acpi_object_type return_type)
 84{
 85	acpi_status status;
 86	u8 must_free = FALSE;
 
 
 87
 88	ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
 89
 90	/* Return buffer must be valid */
 91
 92	if (!return_buffer) {
 93		return_ACPI_STATUS(AE_BAD_PARAMETER);
 94	}
 95
 96	if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
 97		must_free = TRUE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 98	}
 99
100	/* Evaluate the object */
101
102	status =
103	    acpi_evaluate_object(handle, pathname, external_params,
104				 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 (must_free) {
138
139		/* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
140
141		ACPI_FREE(return_buffer->pointer);
 
 
 
 
142		return_buffer->pointer = NULL;
143	}
144
145	return_buffer->length = 0;
146	return_ACPI_STATUS(AE_TYPE);
 
 
 
 
147}
148
149ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
150
151/*******************************************************************************
152 *
153 * FUNCTION:    acpi_evaluate_object
154 *
155 * PARAMETERS:  Handle              - Object handle (optional)
156 *              Pathname            - Object pathname (optional)
157 *              external_params     - List of parameters to pass to method,
158 *                                    terminated by NULL.  May be NULL
159 *                                    if no parameters are being passed.
160 *              return_buffer       - Where to put method's return value (if
161 *                                    any).  If NULL, no value is returned.
162 *
163 * RETURN:      Status
164 *
165 * DESCRIPTION: Find and evaluate the given object, passing the given
166 *              parameters if necessary.  One of "Handle" or "Pathname" must
167 *              be valid (non-null)
168 *
169 ******************************************************************************/
170acpi_status
171acpi_evaluate_object(acpi_handle handle,
172		     acpi_string pathname,
173		     struct acpi_object_list *external_params,
174		     struct acpi_buffer *return_buffer)
175{
176	acpi_status status;
177	struct acpi_evaluate_info *info;
178	acpi_size buffer_space_needed;
179	u32 i;
180
181	ACPI_FUNCTION_TRACE(acpi_evaluate_object);
182
183	/* Allocate and initialize the evaluation information block */
184
185	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
186	if (!info) {
187		return_ACPI_STATUS(AE_NO_MEMORY);
188	}
189
190	info->pathname = pathname;
191
192	/* Convert and validate the device handle */
193
194	info->prefix_node = acpi_ns_validate_handle(handle);
195	if (!info->prefix_node) {
196		status = AE_BAD_PARAMETER;
197		goto cleanup;
198	}
199
200	/*
201	 * If there are parameters to be passed to a control method, the external
202	 * objects must all be converted to internal objects
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
203	 */
204	if (external_params && external_params->count) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
205		/*
206		 * Allocate a new parameter block for the internal objects
207		 * Add 1 to count to allow for null terminated internal list
208		 */
209		info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
210							 external_params->
211							 count +
212							 1) * sizeof(void *));
213		if (!info->parameters) {
214			status = AE_NO_MEMORY;
215			goto cleanup;
216		}
217
218		/* Convert each external object in the list to an internal object */
219
220		for (i = 0; i < external_params->count; i++) {
221			status =
222			    acpi_ut_copy_eobject_to_iobject(&external_params->
223							    pointer[i],
224							    &info->
225							    parameters[i]);
226			if (ACPI_FAILURE(status)) {
227				goto cleanup;
228			}
229		}
230		info->parameters[external_params->count] = NULL;
 
231	}
232
 
 
233	/*
234	 * Three major cases:
235	 * 1) Fully qualified pathname
236	 * 2) No handle, not fully qualified pathname (error)
237	 * 3) Valid handle
238	 */
239	if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
 
240
241		/* The path is fully qualified, just evaluate by name */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
242
243		info->prefix_node = NULL;
244		status = acpi_ns_evaluate(info);
245	} else if (!handle) {
246		/*
247		 * A handle is optional iff a fully qualified pathname is specified.
248		 * Since we've already handled fully qualified names above, this is
249		 * an error
250		 */
251		if (!pathname) {
252			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
253					  "Both Handle and Pathname are NULL"));
254		} else {
255			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
256					  "Null Handle with relative pathname [%s]",
257					  pathname));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
258		}
 
259
260		status = AE_BAD_PARAMETER;
261	} else {
262		/* We have a namespace a node and a possible relative path */
263
264		status = acpi_ns_evaluate(info);
 
 
 
 
 
265	}
266
 
 
 
 
 
 
267	/*
268	 * If we are expecting a return value, and all went well above,
269	 * copy the return value to an external object.
270	 */
271	if (return_buffer) {
272		if (!info->return_object) {
273			return_buffer->length = 0;
274		} else {
275			if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
276			    ACPI_DESC_TYPE_NAMED) {
277				/*
278				 * If we received a NS Node as a return object, this means that
279				 * the object we are evaluating has nothing interesting to
280				 * return (such as a mutex, etc.)  We return an error because
281				 * these types are essentially unsupported by this interface.
282				 * We don't check up front because this makes it easier to add
283				 * support for various types at a later date if necessary.
284				 */
285				status = AE_TYPE;
286				info->return_object = NULL;	/* No need to delete a NS Node */
287				return_buffer->length = 0;
288			}
 
 
 
 
 
289
290			if (ACPI_SUCCESS(status)) {
 
 
291
292				/* Dereference Index and ref_of references */
293
294				acpi_ns_resolve_references(info);
295
296				/* Get the size of the returned object */
297
298				status =
299				    acpi_ut_get_object_size(info->return_object,
300							    &buffer_space_needed);
301				if (ACPI_SUCCESS(status)) {
302
303					/* Validate/Allocate/Clear caller buffer */
304
305					status =
306					    acpi_ut_initialize_buffer
307					    (return_buffer,
308					     buffer_space_needed);
309					if (ACPI_FAILURE(status)) {
310						/*
311						 * Caller's buffer is too small or a new one can't
312						 * be allocated
313						 */
314						ACPI_DEBUG_PRINT((ACPI_DB_INFO,
315								  "Needed buffer size %X, %s\n",
316								  (u32)
317								  buffer_space_needed,
318								  acpi_format_exception
319								  (status)));
320					} else {
321						/* We have enough space for the object, build it */
322
323						status =
324						    acpi_ut_copy_iobject_to_eobject
325						    (info->return_object,
326						     return_buffer);
327					}
328				}
329			}
330		}
331	}
332
 
 
333	if (info->return_object) {
334		/*
335		 * Delete the internal return object. NOTE: Interpreter must be
336		 * locked to avoid race condition.
337		 */
338		acpi_ex_enter_interpreter();
339
340		/* Remove one reference on the return object (should delete it) */
341
342		acpi_ut_remove_reference(info->return_object);
343		acpi_ex_exit_interpreter();
344	}
345
346      cleanup:
347
348	/* Free the input parameter list (if we created one) */
349
350	if (info->parameters) {
351
352		/* Free the allocated parameter block */
353
354		acpi_ut_delete_internal_object_list(info->parameters);
355	}
356
357	ACPI_FREE(info);
358	return_ACPI_STATUS(status);
359}
360
361ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
362
363/*******************************************************************************
364 *
365 * FUNCTION:    acpi_ns_resolve_references
366 *
367 * PARAMETERS:  Info                    - Evaluation info block
368 *
369 * RETURN:      Info->return_object is replaced with the dereferenced object
370 *
371 * DESCRIPTION: Dereference certain reference objects. Called before an
372 *              internal return object is converted to an external union acpi_object.
373 *
374 * Performs an automatic dereference of Index and ref_of reference objects.
375 * These reference objects are not supported by the union acpi_object, so this is a
376 * last resort effort to return something useful. Also, provides compatibility
377 * with other ACPI implementations.
378 *
379 * NOTE: does not handle references within returned package objects or nested
380 * references, but this support could be added later if found to be necessary.
381 *
382 ******************************************************************************/
383static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
384{
385	union acpi_operand_object *obj_desc = NULL;
386	struct acpi_namespace_node *node;
387
388	/* We are interested in reference objects only */
389
390	if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
391		return;
392	}
393
394	/*
395	 * Two types of references are supported - those created by Index and
396	 * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
397	 * to an union acpi_object, so it is not dereferenced here. A ddb_handle
398	 * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
399	 * an union acpi_object.
400	 */
401	switch (info->return_object->reference.class) {
402	case ACPI_REFCLASS_INDEX:
403
404		obj_desc = *(info->return_object->reference.where);
405		break;
406
407	case ACPI_REFCLASS_REFOF:
408
409		node = info->return_object->reference.object;
410		if (node) {
411			obj_desc = node->object;
412		}
413		break;
414
415	default:
 
416		return;
417	}
418
419	/* Replace the existing reference object */
420
421	if (obj_desc) {
422		acpi_ut_add_reference(obj_desc);
423		acpi_ut_remove_reference(info->return_object);
424		info->return_object = obj_desc;
425	}
426
427	return;
428}
429
430/*******************************************************************************
431 *
432 * FUNCTION:    acpi_walk_namespace
433 *
434 * PARAMETERS:  Type                - acpi_object_type to search for
435 *              start_object        - Handle in namespace where search begins
436 *              max_depth           - Depth to which search is to reach
437 *              pre_order_visit     - Called during tree pre-order visit
438 *                                    when an object of "Type" is found
439 *              post_order_visit    - Called during tree post-order visit
440 *                                    when an object of "Type" is found
441 *              Context             - Passed to user function(s) above
442 *              return_value        - Location where return value of
443 *                                    user_function is put if terminated early
444 *
445 * RETURNS      Return value from the user_function if terminated early.
446 *              Otherwise, returns NULL.
447 *
448 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
449 *              starting (and ending) at the object specified by start_handle.
450 *              The callback function is called whenever an object that matches
451 *              the type parameter is found. If the callback function returns
452 *              a non-zero value, the search is terminated immediately and this
453 *              value is returned to the caller.
454 *
455 *              The point of this procedure is to provide a generic namespace
456 *              walk routine that can be called from multiple places to
457 *              provide multiple services; the callback function(s) can be
458 *              tailored to each task, whether it is a print function,
459 *              a compare function, etc.
460 *
461 ******************************************************************************/
462
463acpi_status
464acpi_walk_namespace(acpi_object_type type,
465		    acpi_handle start_object,
466		    u32 max_depth,
467		    acpi_walk_callback pre_order_visit,
468		    acpi_walk_callback post_order_visit,
469		    void *context, void **return_value)
470{
471	acpi_status status;
472
473	ACPI_FUNCTION_TRACE(acpi_walk_namespace);
474
475	/* Parameter validation */
476
477	if ((type > ACPI_TYPE_LOCAL_MAX) ||
478	    (!max_depth) || (!pre_order_visit && !post_order_visit)) {
479		return_ACPI_STATUS(AE_BAD_PARAMETER);
480	}
481
482	/*
483	 * Need to acquire the namespace reader lock to prevent interference
484	 * with any concurrent table unloads (which causes the deletion of
485	 * namespace objects). We cannot allow the deletion of a namespace node
486	 * while the user function is using it. The exception to this are the
487	 * nodes created and deleted during control method execution -- these
488	 * nodes are marked as temporary nodes and are ignored by the namespace
489	 * walk. Thus, control methods can be executed while holding the
490	 * namespace deletion lock (and the user function can execute control
491	 * methods.)
492	 */
493	status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
494	if (ACPI_FAILURE(status)) {
495		return status;
496	}
497
498	/*
499	 * Lock the namespace around the walk. The namespace will be
500	 * unlocked/locked around each call to the user function - since the user
501	 * function must be allowed to make ACPICA calls itself (for example, it
502	 * will typically execute control methods during device enumeration.)
503	 */
504	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
505	if (ACPI_FAILURE(status)) {
506		goto unlock_and_exit;
507	}
508
 
 
 
 
 
 
 
509	status = acpi_ns_walk_namespace(type, start_object, max_depth,
510					ACPI_NS_WALK_UNLOCK, pre_order_visit,
511					post_order_visit, context,
512					return_value);
513
 
514	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
515
516      unlock_and_exit:
517	(void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
518	return_ACPI_STATUS(status);
519}
520
521ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
522
523/*******************************************************************************
524 *
525 * FUNCTION:    acpi_ns_get_device_callback
526 *
527 * PARAMETERS:  Callback from acpi_get_device
528 *
529 * RETURN:      Status
530 *
531 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
532 *              present devices, or if they specified a HID, it filters based
533 *              on that.
534 *
535 ******************************************************************************/
536static acpi_status
537acpi_ns_get_device_callback(acpi_handle obj_handle,
538			    u32 nesting_level,
539			    void *context, void **return_value)
540{
541	struct acpi_get_devices_info *info = context;
542	acpi_status status;
543	struct acpi_namespace_node *node;
544	u32 flags;
545	struct acpica_device_id *hid;
546	struct acpica_device_id_list *cid;
547	u32 i;
548	u8 found;
549	int no_match;
550
551	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
552	if (ACPI_FAILURE(status)) {
553		return (status);
554	}
555
556	node = acpi_ns_validate_handle(obj_handle);
557	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
558	if (ACPI_FAILURE(status)) {
559		return (status);
560	}
561
562	if (!node) {
563		return (AE_BAD_PARAMETER);
564	}
565
566	/*
567	 * First, filter based on the device HID and CID.
568	 *
569	 * 01/2010: For this case where a specific HID is requested, we don't
570	 * want to run _STA until we have an actual HID match. Thus, we will
571	 * not unnecessarily execute _STA on devices for which the caller
572	 * doesn't care about. Previously, _STA was executed unconditionally
573	 * on all devices found here.
574	 *
575	 * A side-effect of this change is that now we will continue to search
576	 * for a matching HID even under device trees where the parent device
577	 * would have returned a _STA that indicates it is not present or
578	 * not functioning (thus aborting the search on that branch).
579	 */
580	if (info->hid != NULL) {
581		status = acpi_ut_execute_HID(node, &hid);
582		if (status == AE_NOT_FOUND) {
583			return (AE_OK);
584		} else if (ACPI_FAILURE(status)) {
585			return (AE_CTRL_DEPTH);
586		}
587
588		no_match = ACPI_STRCMP(hid->string, info->hid);
589		ACPI_FREE(hid);
590
591		if (no_match) {
592			/*
593			 * HID does not match, attempt match within the
594			 * list of Compatible IDs (CIDs)
595			 */
596			status = acpi_ut_execute_CID(node, &cid);
597			if (status == AE_NOT_FOUND) {
598				return (AE_OK);
599			} else if (ACPI_FAILURE(status)) {
600				return (AE_CTRL_DEPTH);
601			}
602
603			/* Walk the CID list */
604
605			found = 0;
606			for (i = 0; i < cid->count; i++) {
607				if (ACPI_STRCMP(cid->ids[i].string, info->hid)
608				    == 0) {
609					found = 1;
 
 
610					break;
611				}
612			}
 
613			ACPI_FREE(cid);
614			if (!found)
615				return (AE_OK);
 
616		}
617	}
618
619	/* Run _STA to determine if device is present */
620
621	status = acpi_ut_execute_STA(node, &flags);
622	if (ACPI_FAILURE(status)) {
623		return (AE_CTRL_DEPTH);
624	}
625
626	if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
627	    !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
628		/*
629		 * Don't examine the children of the device only when the
630		 * device is neither present nor functional. See ACPI spec,
631		 * description of _STA for more information.
632		 */
633		return (AE_CTRL_DEPTH);
634	}
635
636	/* We have a valid device, invoke the user function */
637
638	status = info->user_function(obj_handle, nesting_level, info->context,
639				     return_value);
640	return (status);
641}
642
643/*******************************************************************************
644 *
645 * FUNCTION:    acpi_get_devices
646 *
647 * PARAMETERS:  HID                 - HID to search for. Can be NULL.
648 *              user_function       - Called when a matching object is found
649 *              Context             - Passed to user function
650 *              return_value        - Location where return value of
651 *                                    user_function is put if terminated early
652 *
653 * RETURNS      Return value from the user_function if terminated early.
654 *              Otherwise, returns NULL.
655 *
656 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
657 *              starting (and ending) at the object specified by start_handle.
658 *              The user_function is called whenever an object of type
659 *              Device is found.  If the user function returns
660 *              a non-zero value, the search is terminated immediately and this
661 *              value is returned to the caller.
662 *
663 *              This is a wrapper for walk_namespace, but the callback performs
664 *              additional filtering. Please see acpi_ns_get_device_callback.
665 *
666 ******************************************************************************/
667
668acpi_status
669acpi_get_devices(const char *HID,
670		 acpi_walk_callback user_function,
671		 void *context, void **return_value)
672{
673	acpi_status status;
674	struct acpi_get_devices_info info;
675
676	ACPI_FUNCTION_TRACE(acpi_get_devices);
677
678	/* Parameter validation */
679
680	if (!user_function) {
681		return_ACPI_STATUS(AE_BAD_PARAMETER);
682	}
683
684	/*
685	 * We're going to call their callback from OUR callback, so we need
686	 * to know what it is, and their context parameter.
687	 */
688	info.hid = HID;
689	info.context = context;
690	info.user_function = user_function;
691
692	/*
693	 * Lock the namespace around the walk.
694	 * The namespace will be unlocked/locked around each call
695	 * to the user function - since this function
696	 * must be allowed to make Acpi calls itself.
697	 */
698	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
699	if (ACPI_FAILURE(status)) {
700		return_ACPI_STATUS(status);
701	}
702
703	status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
704					ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
705					acpi_ns_get_device_callback, NULL,
706					&info, return_value);
707
708	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
709	return_ACPI_STATUS(status);
710}
711
712ACPI_EXPORT_SYMBOL(acpi_get_devices)
713
714/*******************************************************************************
715 *
716 * FUNCTION:    acpi_attach_data
717 *
718 * PARAMETERS:  obj_handle          - Namespace node
719 *              Handler             - Handler for this attachment
720 *              Data                - Pointer to data to be attached
721 *
722 * RETURN:      Status
723 *
724 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
725 *
726 ******************************************************************************/
727acpi_status
728acpi_attach_data(acpi_handle obj_handle,
729		 acpi_object_handler handler, void *data)
730{
731	struct acpi_namespace_node *node;
732	acpi_status status;
733
734	/* Parameter validation */
735
736	if (!obj_handle || !handler || !data) {
737		return (AE_BAD_PARAMETER);
738	}
739
740	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
741	if (ACPI_FAILURE(status)) {
742		return (status);
743	}
744
745	/* Convert and validate the handle */
746
747	node = acpi_ns_validate_handle(obj_handle);
748	if (!node) {
749		status = AE_BAD_PARAMETER;
750		goto unlock_and_exit;
751	}
752
753	status = acpi_ns_attach_data(node, handler, data);
754
755      unlock_and_exit:
756	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
757	return (status);
758}
759
760ACPI_EXPORT_SYMBOL(acpi_attach_data)
761
762/*******************************************************************************
763 *
764 * FUNCTION:    acpi_detach_data
765 *
766 * PARAMETERS:  obj_handle          - Namespace node handle
767 *              Handler             - Handler used in call to acpi_attach_data
768 *
769 * RETURN:      Status
770 *
771 * DESCRIPTION: Remove data that was previously attached to a node.
772 *
773 ******************************************************************************/
774acpi_status
775acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
776{
777	struct acpi_namespace_node *node;
778	acpi_status status;
779
780	/* Parameter validation */
781
782	if (!obj_handle || !handler) {
783		return (AE_BAD_PARAMETER);
784	}
785
786	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
787	if (ACPI_FAILURE(status)) {
788		return (status);
789	}
790
791	/* Convert and validate the handle */
792
793	node = acpi_ns_validate_handle(obj_handle);
794	if (!node) {
795		status = AE_BAD_PARAMETER;
796		goto unlock_and_exit;
797	}
798
799	status = acpi_ns_detach_data(node, handler);
800
801      unlock_and_exit:
802	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
803	return (status);
804}
805
806ACPI_EXPORT_SYMBOL(acpi_detach_data)
807
808/*******************************************************************************
809 *
810 * FUNCTION:    acpi_get_data
811 *
812 * PARAMETERS:  obj_handle          - Namespace node
813 *              Handler             - Handler used in call to attach_data
814 *              Data                - Where the data is returned
 
815 *
816 * RETURN:      Status
817 *
818 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 
819 *
820 ******************************************************************************/
821acpi_status
822acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 
823{
824	struct acpi_namespace_node *node;
825	acpi_status status;
826
827	/* Parameter validation */
828
829	if (!obj_handle || !handler || !data) {
830		return (AE_BAD_PARAMETER);
831	}
832
833	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
834	if (ACPI_FAILURE(status)) {
835		return (status);
836	}
837
838	/* Convert and validate the handle */
839
840	node = acpi_ns_validate_handle(obj_handle);
841	if (!node) {
842		status = AE_BAD_PARAMETER;
843		goto unlock_and_exit;
844	}
845
846	status = acpi_ns_get_attached_data(node, handler, data);
 
 
 
847
848      unlock_and_exit:
849	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
850	return (status);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
851}
852
853ACPI_EXPORT_SYMBOL(acpi_get_data)
v6.9.4
  1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
  2/*******************************************************************************
  3 *
  4 * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
  5 *                         ACPI Object evaluation interfaces
  6 *
  7 ******************************************************************************/
  8
  9#define EXPORT_ACPI_INTERFACES
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10
 
 11#include <acpi/acpi.h>
 12#include "accommon.h"
 13#include "acnamesp.h"
 14#include "acinterp.h"
 15
 16#define _COMPONENT          ACPI_NAMESPACE
 17ACPI_MODULE_NAME("nsxfeval")
 18
 19/* Local prototypes */
 20static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
 21
 22/*******************************************************************************
 23 *
 24 * FUNCTION:    acpi_evaluate_object_typed
 25 *
 26 * PARAMETERS:  handle              - Object handle (optional)
 27 *              pathname            - Object pathname (optional)
 28 *              external_params     - List of parameters to pass to a method,
 29 *                                    terminated by NULL. May be NULL
 30 *                                    if no parameters are being passed.
 31 *              return_buffer       - Where to put the object's return value (if
 32 *                                    any). If NULL, no value is returned.
 33 *              return_type         - Expected type of return object
 34 *
 35 * RETURN:      Status
 36 *
 37 * DESCRIPTION: Find and evaluate the given object, passing the given
 38 *              parameters if necessary. One of "Handle" or "Pathname" must
 39 *              be valid (non-null)
 40 *
 41 ******************************************************************************/
 42
 43acpi_status
 44acpi_evaluate_object_typed(acpi_handle handle,
 45			   acpi_string pathname,
 46			   struct acpi_object_list *external_params,
 47			   struct acpi_buffer *return_buffer,
 48			   acpi_object_type return_type)
 49{
 50	acpi_status status;
 51	u8 free_buffer_on_error = FALSE;
 52	acpi_handle target_handle;
 53	char *full_pathname;
 54
 55	ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
 56
 57	/* Return buffer must be valid */
 58
 59	if (!return_buffer) {
 60		return_ACPI_STATUS(AE_BAD_PARAMETER);
 61	}
 62
 63	if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
 64		free_buffer_on_error = TRUE;
 65	}
 66
 67	/* Get a handle here, in order to build an error message if needed */
 68
 69	target_handle = handle;
 70	if (pathname) {
 71		status = acpi_get_handle(handle, pathname, &target_handle);
 72		if (ACPI_FAILURE(status)) {
 73			return_ACPI_STATUS(status);
 74		}
 75	}
 76
 77	full_pathname = acpi_ns_get_external_pathname(target_handle);
 78	if (!full_pathname) {
 79		return_ACPI_STATUS(AE_NO_MEMORY);
 80	}
 81
 82	/* Evaluate the object */
 83
 84	status = acpi_evaluate_object(target_handle, NULL, external_params,
 85				      return_buffer);
 
 86	if (ACPI_FAILURE(status)) {
 87		goto exit;
 88	}
 89
 90	/* Type ANY means "don't care about return value type" */
 91
 92	if (return_type == ACPI_TYPE_ANY) {
 93		goto exit;
 94	}
 95
 96	if (return_buffer->length == 0) {
 97
 98		/* Error because caller specifically asked for a return value */
 99
100		ACPI_ERROR((AE_INFO, "%s did not return any object",
101			    full_pathname));
102		status = AE_NULL_OBJECT;
103		goto exit;
104	}
105
106	/* Examine the object type returned from evaluate_object */
107
108	if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
109		goto exit;
110	}
111
112	/* Return object type does not match requested type */
113
114	ACPI_ERROR((AE_INFO,
115		    "Incorrect return type from %s - received [%s], requested [%s]",
116		    full_pathname,
117		    acpi_ut_get_type_name(((union acpi_object *)return_buffer->
118					   pointer)->type),
119		    acpi_ut_get_type_name(return_type)));
120
121	if (free_buffer_on_error) {
122		/*
123		 * Free a buffer created via ACPI_ALLOCATE_BUFFER.
124		 * Note: We use acpi_os_free here because acpi_os_allocate was used
125		 * to allocate the buffer. This purposefully bypasses the
126		 * (optionally enabled) allocation tracking mechanism since we
127		 * only want to track internal allocations.
128		 */
129		acpi_os_free(return_buffer->pointer);
130		return_buffer->pointer = NULL;
131	}
132
133	return_buffer->length = 0;
134	status = AE_TYPE;
135
136exit:
137	ACPI_FREE(full_pathname);
138	return_ACPI_STATUS(status);
139}
140
141ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
142
143/*******************************************************************************
144 *
145 * FUNCTION:    acpi_evaluate_object
146 *
147 * PARAMETERS:  handle              - Object handle (optional)
148 *              pathname            - Object pathname (optional)
149 *              external_params     - List of parameters to pass to method,
150 *                                    terminated by NULL. May be NULL
151 *                                    if no parameters are being passed.
152 *              return_buffer       - Where to put method's return value (if
153 *                                    any). If NULL, no value is returned.
154 *
155 * RETURN:      Status
156 *
157 * DESCRIPTION: Find and evaluate the given object, passing the given
158 *              parameters if necessary. One of "Handle" or "Pathname" must
159 *              be valid (non-null)
160 *
161 ******************************************************************************/
162acpi_status
163acpi_evaluate_object(acpi_handle handle,
164		     acpi_string pathname,
165		     struct acpi_object_list *external_params,
166		     struct acpi_buffer *return_buffer)
167{
168	acpi_status status;
169	struct acpi_evaluate_info *info;
170	acpi_size buffer_space_needed;
171	u32 i;
172
173	ACPI_FUNCTION_TRACE(acpi_evaluate_object);
174
175	/* Allocate and initialize the evaluation information block */
176
177	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
178	if (!info) {
179		return_ACPI_STATUS(AE_NO_MEMORY);
180	}
181
 
 
182	/* Convert and validate the device handle */
183
184	info->prefix_node = acpi_ns_validate_handle(handle);
185	if (!info->prefix_node) {
186		status = AE_BAD_PARAMETER;
187		goto cleanup;
188	}
189
190	/*
191	 * Get the actual namespace node for the target object.
192	 * Handles these cases:
193	 *
194	 * 1) Null node, valid pathname from root (absolute path)
195	 * 2) Node and valid pathname (path relative to Node)
196	 * 3) Node, Null pathname
197	 */
198	if ((pathname) && (ACPI_IS_ROOT_PREFIX(pathname[0]))) {
199
200		/* The path is fully qualified, just evaluate by name */
201
202		info->prefix_node = NULL;
203	} else if (!handle) {
204		/*
205		 * A handle is optional iff a fully qualified pathname is specified.
206		 * Since we've already handled fully qualified names above, this is
207		 * an error.
208		 */
209		if (!pathname) {
210			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
211					  "Both Handle and Pathname are NULL"));
212		} else {
213			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
214					  "Null Handle with relative pathname [%s]",
215					  pathname));
216		}
217
218		status = AE_BAD_PARAMETER;
219		goto cleanup;
220	}
221
222	info->relative_pathname = pathname;
223
224	/*
225	 * Convert all external objects passed as arguments to the
226	 * internal version(s).
227	 */
228	if (external_params && external_params->count) {
229		info->param_count = (u16)external_params->count;
230
231		/* Warn on impossible argument count */
232
233		if (info->param_count > ACPI_METHOD_NUM_ARGS) {
234			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
235					      ACPI_WARN_ALWAYS,
236					      "Excess arguments (%u) - using only %u",
237					      info->param_count,
238					      ACPI_METHOD_NUM_ARGS));
239
240			info->param_count = ACPI_METHOD_NUM_ARGS;
241		}
242
243		/*
244		 * Allocate a new parameter block for the internal objects
245		 * Add 1 to count to allow for null terminated internal list
246		 */
247		info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)info->
248							 param_count +
 
249							 1) * sizeof(void *));
250		if (!info->parameters) {
251			status = AE_NO_MEMORY;
252			goto cleanup;
253		}
254
255		/* Convert each external object in the list to an internal object */
256
257		for (i = 0; i < info->param_count; i++) {
258			status =
259			    acpi_ut_copy_eobject_to_iobject(&external_params->
260							    pointer[i],
261							    &info->
262							    parameters[i]);
263			if (ACPI_FAILURE(status)) {
264				goto cleanup;
265			}
266		}
267
268		info->parameters[info->param_count] = NULL;
269	}
270
271#ifdef _FUTURE_FEATURE
272
273	/*
274	 * Begin incoming argument count analysis. Check for too few args
275	 * and too many args.
 
 
276	 */
277	switch (acpi_ns_get_type(info->node)) {
278	case ACPI_TYPE_METHOD:
279
280		/* Check incoming argument count against the method definition */
281
282		if (info->obj_desc->method.param_count > info->param_count) {
283			ACPI_ERROR((AE_INFO,
284				    "Insufficient arguments (%u) - %u are required",
285				    info->param_count,
286				    info->obj_desc->method.param_count));
287
288			status = AE_MISSING_ARGUMENTS;
289			goto cleanup;
290		}
291
292		else if (info->obj_desc->method.param_count < info->param_count) {
293			ACPI_WARNING((AE_INFO,
294				      "Excess arguments (%u) - only %u are required",
295				      info->param_count,
296				      info->obj_desc->method.param_count));
297
298			/* Just pass the required number of arguments */
299
300			info->param_count = info->obj_desc->method.param_count;
301		}
302
 
 
 
303		/*
304		 * Any incoming external objects to be passed as arguments to the
305		 * method must be converted to internal objects
 
306		 */
307		if (info->param_count) {
308			/*
309			 * Allocate a new parameter block for the internal objects
310			 * Add 1 to count to allow for null terminated internal list
311			 */
312			info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
313								 info->
314								 param_count +
315								 1) *
316								sizeof(void *));
317			if (!info->parameters) {
318				status = AE_NO_MEMORY;
319				goto cleanup;
320			}
321
322			/* Convert each external object in the list to an internal object */
323
324			for (i = 0; i < info->param_count; i++) {
325				status =
326				    acpi_ut_copy_eobject_to_iobject
327				    (&external_params->pointer[i],
328				     &info->parameters[i]);
329				if (ACPI_FAILURE(status)) {
330					goto cleanup;
331				}
332			}
333
334			info->parameters[info->param_count] = NULL;
335		}
336		break;
337
338	default:
339
340		/* Warn if arguments passed to an object that is not a method */
341
342		if (info->param_count) {
343			ACPI_WARNING((AE_INFO,
344				      "%u arguments were passed to a non-method ACPI object",
345				      info->param_count));
346		}
347		break;
348	}
349
350#endif
351
352	/* Now we can evaluate the object */
353
354	status = acpi_ns_evaluate(info);
355
356	/*
357	 * If we are expecting a return value, and all went well above,
358	 * copy the return value to an external object.
359	 */
360	if (!return_buffer) {
361		goto cleanup_return_object;
362	}
363
364	if (!info->return_object) {
365		return_buffer->length = 0;
366		goto cleanup;
367	}
368
369	if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
370	    ACPI_DESC_TYPE_NAMED) {
371		/*
372		 * If we received a NS Node as a return object, this means that
373		 * the object we are evaluating has nothing interesting to
374		 * return (such as a mutex, etc.)  We return an error because
375		 * these types are essentially unsupported by this interface.
376		 * We don't check up front because this makes it easier to add
377		 * support for various types at a later date if necessary.
378		 */
379		status = AE_TYPE;
380		info->return_object = NULL;	/* No need to delete a NS Node */
381		return_buffer->length = 0;
382	}
383
384	if (ACPI_FAILURE(status)) {
385		goto cleanup_return_object;
386	}
387
388	/* Dereference Index and ref_of references */
389
390	acpi_ns_resolve_references(info);
391
392	/* Get the size of the returned object */
393
394	status = acpi_ut_get_object_size(info->return_object,
395					 &buffer_space_needed);
396	if (ACPI_SUCCESS(status)) {
397
398		/* Validate/Allocate/Clear caller buffer */
399
400		status = acpi_ut_initialize_buffer(return_buffer,
401						   buffer_space_needed);
402		if (ACPI_FAILURE(status)) {
403			/*
404			 * Caller's buffer is too small or a new one can't
405			 * be allocated
406			 */
407			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
408					  "Needed buffer size %X, %s\n",
409					  (u32)buffer_space_needed,
410					  acpi_format_exception(status)));
411		} else {
412			/* We have enough space for the object, build it */
413
414			status =
415			    acpi_ut_copy_iobject_to_eobject(info->return_object,
416							    return_buffer);
 
 
 
 
 
 
 
 
 
417		}
418	}
419
420cleanup_return_object:
421
422	if (info->return_object) {
423		/*
424		 * Delete the internal return object. NOTE: Interpreter must be
425		 * locked to avoid race condition.
426		 */
427		acpi_ex_enter_interpreter();
428
429		/* Remove one reference on the return object (should delete it) */
430
431		acpi_ut_remove_reference(info->return_object);
432		acpi_ex_exit_interpreter();
433	}
434
435cleanup:
436
437	/* Free the input parameter list (if we created one) */
438
439	if (info->parameters) {
440
441		/* Free the allocated parameter block */
442
443		acpi_ut_delete_internal_object_list(info->parameters);
444	}
445
446	ACPI_FREE(info);
447	return_ACPI_STATUS(status);
448}
449
450ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
451
452/*******************************************************************************
453 *
454 * FUNCTION:    acpi_ns_resolve_references
455 *
456 * PARAMETERS:  info                    - Evaluation info block
457 *
458 * RETURN:      Info->return_object is replaced with the dereferenced object
459 *
460 * DESCRIPTION: Dereference certain reference objects. Called before an
461 *              internal return object is converted to an external union acpi_object.
462 *
463 * Performs an automatic dereference of Index and ref_of reference objects.
464 * These reference objects are not supported by the union acpi_object, so this is a
465 * last resort effort to return something useful. Also, provides compatibility
466 * with other ACPI implementations.
467 *
468 * NOTE: does not handle references within returned package objects or nested
469 * references, but this support could be added later if found to be necessary.
470 *
471 ******************************************************************************/
472static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
473{
474	union acpi_operand_object *obj_desc = NULL;
475	struct acpi_namespace_node *node;
476
477	/* We are interested in reference objects only */
478
479	if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
480		return;
481	}
482
483	/*
484	 * Two types of references are supported - those created by Index and
485	 * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
486	 * to a union acpi_object, so it is not dereferenced here. A ddb_handle
487	 * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
488	 * a union acpi_object.
489	 */
490	switch (info->return_object->reference.class) {
491	case ACPI_REFCLASS_INDEX:
492
493		obj_desc = *(info->return_object->reference.where);
494		break;
495
496	case ACPI_REFCLASS_REFOF:
497
498		node = info->return_object->reference.object;
499		if (node) {
500			obj_desc = node->object;
501		}
502		break;
503
504	default:
505
506		return;
507	}
508
509	/* Replace the existing reference object */
510
511	if (obj_desc) {
512		acpi_ut_add_reference(obj_desc);
513		acpi_ut_remove_reference(info->return_object);
514		info->return_object = obj_desc;
515	}
516
517	return;
518}
519
520/*******************************************************************************
521 *
522 * FUNCTION:    acpi_walk_namespace
523 *
524 * PARAMETERS:  type                - acpi_object_type to search for
525 *              start_object        - Handle in namespace where search begins
526 *              max_depth           - Depth to which search is to reach
527 *              descending_callback - Called during tree descent
528 *                                    when an object of "Type" is found
529 *              ascending_callback  - Called during tree ascent
530 *                                    when an object of "Type" is found
531 *              context             - Passed to user function(s) above
532 *              return_value        - Location where return value of
533 *                                    user_function is put if terminated early
534 *
535 * RETURNS      Return value from the user_function if terminated early.
536 *              Otherwise, returns NULL.
537 *
538 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
539 *              starting (and ending) at the object specified by start_handle.
540 *              The callback function is called whenever an object that matches
541 *              the type parameter is found. If the callback function returns
542 *              a non-zero value, the search is terminated immediately and this
543 *              value is returned to the caller.
544 *
545 *              The point of this procedure is to provide a generic namespace
546 *              walk routine that can be called from multiple places to
547 *              provide multiple services; the callback function(s) can be
548 *              tailored to each task, whether it is a print function,
549 *              a compare function, etc.
550 *
551 ******************************************************************************/
552
553acpi_status
554acpi_walk_namespace(acpi_object_type type,
555		    acpi_handle start_object,
556		    u32 max_depth,
557		    acpi_walk_callback descending_callback,
558		    acpi_walk_callback ascending_callback,
559		    void *context, void **return_value)
560{
561	acpi_status status;
562
563	ACPI_FUNCTION_TRACE(acpi_walk_namespace);
564
565	/* Parameter validation */
566
567	if ((type > ACPI_TYPE_LOCAL_MAX) ||
568	    (!max_depth) || (!descending_callback && !ascending_callback)) {
569		return_ACPI_STATUS(AE_BAD_PARAMETER);
570	}
571
572	/*
573	 * Need to acquire the namespace reader lock to prevent interference
574	 * with any concurrent table unloads (which causes the deletion of
575	 * namespace objects). We cannot allow the deletion of a namespace node
576	 * while the user function is using it. The exception to this are the
577	 * nodes created and deleted during control method execution -- these
578	 * nodes are marked as temporary nodes and are ignored by the namespace
579	 * walk. Thus, control methods can be executed while holding the
580	 * namespace deletion lock (and the user function can execute control
581	 * methods.)
582	 */
583	status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
584	if (ACPI_FAILURE(status)) {
585		return_ACPI_STATUS(status);
586	}
587
588	/*
589	 * Lock the namespace around the walk. The namespace will be
590	 * unlocked/locked around each call to the user function - since the user
591	 * function must be allowed to make ACPICA calls itself (for example, it
592	 * will typically execute control methods during device enumeration.)
593	 */
594	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
595	if (ACPI_FAILURE(status)) {
596		goto unlock_and_exit;
597	}
598
599	/* Now we can validate the starting node */
600
601	if (!acpi_ns_validate_handle(start_object)) {
602		status = AE_BAD_PARAMETER;
603		goto unlock_and_exit2;
604	}
605
606	status = acpi_ns_walk_namespace(type, start_object, max_depth,
607					ACPI_NS_WALK_UNLOCK,
608					descending_callback, ascending_callback,
609					context, return_value);
610
611unlock_and_exit2:
612	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
613
614unlock_and_exit:
615	(void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
616	return_ACPI_STATUS(status);
617}
618
619ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
620
621/*******************************************************************************
622 *
623 * FUNCTION:    acpi_ns_get_device_callback
624 *
625 * PARAMETERS:  Callback from acpi_get_device
626 *
627 * RETURN:      Status
628 *
629 * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
630 *              present devices, or if they specified a HID, it filters based
631 *              on that.
632 *
633 ******************************************************************************/
634static acpi_status
635acpi_ns_get_device_callback(acpi_handle obj_handle,
636			    u32 nesting_level,
637			    void *context, void **return_value)
638{
639	struct acpi_get_devices_info *info = context;
640	acpi_status status;
641	struct acpi_namespace_node *node;
642	u32 flags;
643	struct acpi_pnp_device_id *hid;
644	struct acpi_pnp_device_id_list *cid;
645	u32 i;
646	u8 found;
647	int no_match;
648
649	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
650	if (ACPI_FAILURE(status)) {
651		return (status);
652	}
653
654	node = acpi_ns_validate_handle(obj_handle);
655	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
656	if (ACPI_FAILURE(status)) {
657		return (status);
658	}
659
660	if (!node) {
661		return (AE_BAD_PARAMETER);
662	}
663
664	/*
665	 * First, filter based on the device HID and CID.
666	 *
667	 * 01/2010: For this case where a specific HID is requested, we don't
668	 * want to run _STA until we have an actual HID match. Thus, we will
669	 * not unnecessarily execute _STA on devices for which the caller
670	 * doesn't care about. Previously, _STA was executed unconditionally
671	 * on all devices found here.
672	 *
673	 * A side-effect of this change is that now we will continue to search
674	 * for a matching HID even under device trees where the parent device
675	 * would have returned a _STA that indicates it is not present or
676	 * not functioning (thus aborting the search on that branch).
677	 */
678	if (info->hid != NULL) {
679		status = acpi_ut_execute_HID(node, &hid);
680		if (status == AE_NOT_FOUND) {
681			return (AE_OK);
682		} else if (ACPI_FAILURE(status)) {
683			return (AE_CTRL_DEPTH);
684		}
685
686		no_match = strcmp(hid->string, info->hid);
687		ACPI_FREE(hid);
688
689		if (no_match) {
690			/*
691			 * HID does not match, attempt match within the
692			 * list of Compatible IDs (CIDs)
693			 */
694			status = acpi_ut_execute_CID(node, &cid);
695			if (status == AE_NOT_FOUND) {
696				return (AE_OK);
697			} else if (ACPI_FAILURE(status)) {
698				return (AE_CTRL_DEPTH);
699			}
700
701			/* Walk the CID list */
702
703			found = FALSE;
704			for (i = 0; i < cid->count; i++) {
705				if (strcmp(cid->ids[i].string, info->hid) == 0) {
706
707					/* Found a matching CID */
708
709					found = TRUE;
710					break;
711				}
712			}
713
714			ACPI_FREE(cid);
715			if (!found) {
716				return (AE_OK);
717			}
718		}
719	}
720
721	/* Run _STA to determine if device is present */
722
723	status = acpi_ut_execute_STA(node, &flags);
724	if (ACPI_FAILURE(status)) {
725		return (AE_CTRL_DEPTH);
726	}
727
728	if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
729	    !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
730		/*
731		 * Don't examine the children of the device only when the
732		 * device is neither present nor functional. See ACPI spec,
733		 * description of _STA for more information.
734		 */
735		return (AE_CTRL_DEPTH);
736	}
737
738	/* We have a valid device, invoke the user function */
739
740	status = info->user_function(obj_handle, nesting_level,
741				     info->context, return_value);
742	return (status);
743}
744
745/*******************************************************************************
746 *
747 * FUNCTION:    acpi_get_devices
748 *
749 * PARAMETERS:  HID                 - HID to search for. Can be NULL.
750 *              user_function       - Called when a matching object is found
751 *              context             - Passed to user function
752 *              return_value        - Location where return value of
753 *                                    user_function is put if terminated early
754 *
755 * RETURNS      Return value from the user_function if terminated early.
756 *              Otherwise, returns NULL.
757 *
758 * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
759 *              starting (and ending) at the object specified by start_handle.
760 *              The user_function is called whenever an object of type
761 *              Device is found. If the user function returns
762 *              a non-zero value, the search is terminated immediately and this
763 *              value is returned to the caller.
764 *
765 *              This is a wrapper for walk_namespace, but the callback performs
766 *              additional filtering. Please see acpi_ns_get_device_callback.
767 *
768 ******************************************************************************/
769
770acpi_status
771acpi_get_devices(const char *HID,
772		 acpi_walk_callback user_function,
773		 void *context, void **return_value)
774{
775	acpi_status status;
776	struct acpi_get_devices_info info;
777
778	ACPI_FUNCTION_TRACE(acpi_get_devices);
779
780	/* Parameter validation */
781
782	if (!user_function) {
783		return_ACPI_STATUS(AE_BAD_PARAMETER);
784	}
785
786	/*
787	 * We're going to call their callback from OUR callback, so we need
788	 * to know what it is, and their context parameter.
789	 */
790	info.hid = HID;
791	info.context = context;
792	info.user_function = user_function;
793
794	/*
795	 * Lock the namespace around the walk.
796	 * The namespace will be unlocked/locked around each call
797	 * to the user function - since this function
798	 * must be allowed to make Acpi calls itself.
799	 */
800	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
801	if (ACPI_FAILURE(status)) {
802		return_ACPI_STATUS(status);
803	}
804
805	status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
806					ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
807					acpi_ns_get_device_callback, NULL,
808					&info, return_value);
809
810	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
811	return_ACPI_STATUS(status);
812}
813
814ACPI_EXPORT_SYMBOL(acpi_get_devices)
815
816/*******************************************************************************
817 *
818 * FUNCTION:    acpi_attach_data
819 *
820 * PARAMETERS:  obj_handle          - Namespace node
821 *              handler             - Handler for this attachment
822 *              data                - Pointer to data to be attached
823 *
824 * RETURN:      Status
825 *
826 * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
827 *
828 ******************************************************************************/
829acpi_status
830acpi_attach_data(acpi_handle obj_handle,
831		 acpi_object_handler handler, void *data)
832{
833	struct acpi_namespace_node *node;
834	acpi_status status;
835
836	/* Parameter validation */
837
838	if (!obj_handle || !handler || !data) {
839		return (AE_BAD_PARAMETER);
840	}
841
842	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
843	if (ACPI_FAILURE(status)) {
844		return (status);
845	}
846
847	/* Convert and validate the handle */
848
849	node = acpi_ns_validate_handle(obj_handle);
850	if (!node) {
851		status = AE_BAD_PARAMETER;
852		goto unlock_and_exit;
853	}
854
855	status = acpi_ns_attach_data(node, handler, data);
856
857unlock_and_exit:
858	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
859	return (status);
860}
861
862ACPI_EXPORT_SYMBOL(acpi_attach_data)
863
864/*******************************************************************************
865 *
866 * FUNCTION:    acpi_detach_data
867 *
868 * PARAMETERS:  obj_handle          - Namespace node handle
869 *              handler             - Handler used in call to acpi_attach_data
870 *
871 * RETURN:      Status
872 *
873 * DESCRIPTION: Remove data that was previously attached to a node.
874 *
875 ******************************************************************************/
876acpi_status
877acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
878{
879	struct acpi_namespace_node *node;
880	acpi_status status;
881
882	/* Parameter validation */
883
884	if (!obj_handle || !handler) {
885		return (AE_BAD_PARAMETER);
886	}
887
888	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
889	if (ACPI_FAILURE(status)) {
890		return (status);
891	}
892
893	/* Convert and validate the handle */
894
895	node = acpi_ns_validate_handle(obj_handle);
896	if (!node) {
897		status = AE_BAD_PARAMETER;
898		goto unlock_and_exit;
899	}
900
901	status = acpi_ns_detach_data(node, handler);
902
903unlock_and_exit:
904	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
905	return (status);
906}
907
908ACPI_EXPORT_SYMBOL(acpi_detach_data)
909
910/*******************************************************************************
911 *
912 * FUNCTION:    acpi_get_data_full
913 *
914 * PARAMETERS:  obj_handle          - Namespace node
915 *              handler             - Handler used in call to attach_data
916 *              data                - Where the data is returned
917 *              callback            - function to execute before returning
918 *
919 * RETURN:      Status
920 *
921 * DESCRIPTION: Retrieve data that was previously attached to a namespace node
922 *              and execute a callback before returning.
923 *
924 ******************************************************************************/
925acpi_status
926acpi_get_data_full(acpi_handle obj_handle, acpi_object_handler handler,
927		   void **data, void (*callback)(void *))
928{
929	struct acpi_namespace_node *node;
930	acpi_status status;
931
932	/* Parameter validation */
933
934	if (!obj_handle || !handler || !data) {
935		return (AE_BAD_PARAMETER);
936	}
937
938	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
939	if (ACPI_FAILURE(status)) {
940		return (status);
941	}
942
943	/* Convert and validate the handle */
944
945	node = acpi_ns_validate_handle(obj_handle);
946	if (!node) {
947		status = AE_BAD_PARAMETER;
948		goto unlock_and_exit;
949	}
950
951	status = acpi_ns_get_attached_data(node, handler, data);
952	if (ACPI_SUCCESS(status) && callback) {
953		callback(*data);
954	}
955
956unlock_and_exit:
957	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
958	return (status);
959}
960
961ACPI_EXPORT_SYMBOL(acpi_get_data_full)
962
963/*******************************************************************************
964 *
965 * FUNCTION:    acpi_get_data
966 *
967 * PARAMETERS:  obj_handle          - Namespace node
968 *              handler             - Handler used in call to attach_data
969 *              data                - Where the data is returned
970 *
971 * RETURN:      Status
972 *
973 * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
974 *
975 ******************************************************************************/
976acpi_status
977acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
978{
979	return acpi_get_data_full(obj_handle, handler, data, NULL);
980}
981
982ACPI_EXPORT_SYMBOL(acpi_get_data)