1/*******************************************************************************
2 *
3 * Module Name: nseval - Object evaluation, includes control method execution
4 *
5 ******************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2015, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions, and the following disclaimer,
16 *    without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 *    substantially similar to the "NO WARRANTY" disclaimer below
19 *    ("Disclaimer") and any redistribution must be conditioned upon
20 *    including a substantially similar Disclaimer requirement for further
21 *    binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 *    of any contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44#include <acpi/acpi.h>
45#include "accommon.h"
46#include "acparser.h"
47#include "acinterp.h"
48#include "acnamesp.h"
49
50#define _COMPONENT          ACPI_NAMESPACE
51ACPI_MODULE_NAME("nseval")
52
53/* Local prototypes */
54static void
55acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
56			 struct acpi_evaluate_info *info);
57
58/*******************************************************************************
59 *
60 * FUNCTION:    acpi_ns_evaluate
61 *
62 * PARAMETERS:  info            - Evaluation info block, contains these fields
63 *                                and more:
64 *                  prefix_node     - Prefix or Method/Object Node to execute
65 *                  relative_path   - Name of method to execute, If NULL, the
66 *                                    Node is the object to execute
67 *                  parameters      - List of parameters to pass to the method,
68 *                                    terminated by NULL. Params itself may be
69 *                                    NULL if no parameters are being passed.
70 *                  parameter_type  - Type of Parameter list
71 *                  return_object   - Where to put method's return value (if
72 *                                    any). If NULL, no value is returned.
73 *                  flags           - ACPI_IGNORE_RETURN_VALUE to delete return
74 *
75 * RETURN:      Status
76 *
77 * DESCRIPTION: Execute a control method or return the current value of an
78 *              ACPI namespace object.
79 *
80 * MUTEX:       Locks interpreter
81 *
82 ******************************************************************************/
83
84acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
85{
86	acpi_status status;
87
88	ACPI_FUNCTION_TRACE(ns_evaluate);
89
90	if (!info) {
91		return_ACPI_STATUS(AE_BAD_PARAMETER);
92	}
93
94	if (!info->node) {
95		/*
96		 * Get the actual namespace node for the target object if we
97		 * need to. Handles these cases:
98		 *
99		 * 1) Null node, valid pathname from root (absolute path)
100		 * 2) Node and valid pathname (path relative to Node)
101		 * 3) Node, Null pathname
102		 */
103		status =
104		    acpi_ns_get_node(info->prefix_node, info->relative_pathname,
105				     ACPI_NS_NO_UPSEARCH, &info->node);
106		if (ACPI_FAILURE(status)) {
107			return_ACPI_STATUS(status);
108		}
109	}
110
111	/*
112	 * For a method alias, we must grab the actual method node so that
113	 * proper scoping context will be established before execution.
114	 */
115	if (acpi_ns_get_type(info->node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) {
116		info->node =
117		    ACPI_CAST_PTR(struct acpi_namespace_node,
118				  info->node->object);
119	}
120
121	/* Complete the info block initialization */
122
123	info->return_object = NULL;
124	info->node_flags = info->node->flags;
125	info->obj_desc = acpi_ns_get_attached_object(info->node);
126
127	ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n",
128			  info->relative_pathname, info->node,
129			  acpi_ns_get_attached_object(info->node)));
130
131	/* Get info if we have a predefined name (_HID, etc.) */
132
133	info->predefined =
134	    acpi_ut_match_predefined_method(info->node->name.ascii);
135
136	/* Get the full pathname to the object, for use in warning messages */
137
138	info->full_pathname = acpi_ns_get_external_pathname(info->node);
139	if (!info->full_pathname) {
140		return_ACPI_STATUS(AE_NO_MEMORY);
141	}
142
143	/* Count the number of arguments being passed in */
144
145	info->param_count = 0;
146	if (info->parameters) {
147		while (info->parameters[info->param_count]) {
148			info->param_count++;
149		}
150
151		/* Warn on impossible argument count */
152
153		if (info->param_count > ACPI_METHOD_NUM_ARGS) {
154			ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
155					      ACPI_WARN_ALWAYS,
156					      "Excess arguments (%u) - using only %u",
157					      info->param_count,
158					      ACPI_METHOD_NUM_ARGS));
159
160			info->param_count = ACPI_METHOD_NUM_ARGS;
161		}
162	}
163
164	/*
165	 * For predefined names: Check that the declared argument count
166	 * matches the ACPI spec -- otherwise this is a BIOS error.
167	 */
168	acpi_ns_check_acpi_compliance(info->full_pathname, info->node,
169				      info->predefined);
170
171	/*
172	 * For all names: Check that the incoming argument count for
173	 * this method/object matches the actual ASL/AML definition.
174	 */
175	acpi_ns_check_argument_count(info->full_pathname, info->node,
176				     info->param_count, info->predefined);
177
178	/* For predefined names: Typecheck all incoming arguments */
179
180	acpi_ns_check_argument_types(info);
181
182	/*
183	 * Three major evaluation cases:
184	 *
185	 * 1) Object types that cannot be evaluated by definition
186	 * 2) The object is a control method -- execute it
187	 * 3) The object is not a method -- just return it's current value
188	 */
189	switch (acpi_ns_get_type(info->node)) {
190	case ACPI_TYPE_DEVICE:
191	case ACPI_TYPE_EVENT:
192	case ACPI_TYPE_MUTEX:
193	case ACPI_TYPE_REGION:
194	case ACPI_TYPE_THERMAL:
195	case ACPI_TYPE_LOCAL_SCOPE:
196		/*
197		 * 1) Disallow evaluation of certain object types. For these,
198		 *    object evaluation is undefined and not supported.
199		 */
200		ACPI_ERROR((AE_INFO,
201			    "%s: Evaluation of object type [%s] is not supported",
202			    info->full_pathname,
203			    acpi_ut_get_type_name(info->node->type)));
204
205		status = AE_TYPE;
206		goto cleanup;
207
208	case ACPI_TYPE_METHOD:
209		/*
210		 * 2) Object is a control method - execute it
211		 */
212
213		/* Verify that there is a method object associated with this node */
214
215		if (!info->obj_desc) {
216			ACPI_ERROR((AE_INFO,
217				    "%s: Method has no attached sub-object",
218				    info->full_pathname));
219			status = AE_NULL_OBJECT;
220			goto cleanup;
221		}
222
223		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
224				  "**** Execute method [%s] at AML address %p length %X\n",
225				  info->full_pathname,
226				  info->obj_desc->method.aml_start + 1,
227				  info->obj_desc->method.aml_length - 1));
228
229		/*
230		 * Any namespace deletion must acquire both the namespace and
231		 * interpreter locks to ensure that no thread is using the portion of
232		 * the namespace that is being deleted.
233		 *
234		 * Execute the method via the interpreter. The interpreter is locked
235		 * here before calling into the AML parser
236		 */
237		acpi_ex_enter_interpreter();
238		status = acpi_ps_execute_method(info);
239		acpi_ex_exit_interpreter();
240		break;
241
242	default:
243		/*
244		 * 3) All other non-method objects -- get the current object value
245		 */
246
247		/*
248		 * Some objects require additional resolution steps (e.g., the Node
249		 * may be a field that must be read, etc.) -- we can't just grab
250		 * the object out of the node.
251		 *
252		 * Use resolve_node_to_value() to get the associated value.
253		 *
254		 * NOTE: we can get away with passing in NULL for a walk state because
255		 * the Node is guaranteed to not be a reference to either a method
256		 * local or a method argument (because this interface is never called
257		 * from a running method.)
258		 *
259		 * Even though we do not directly invoke the interpreter for object
260		 * resolution, we must lock it because we could access an op_region.
261		 * The op_region access code assumes that the interpreter is locked.
262		 */
263		acpi_ex_enter_interpreter();
264
265		/* TBD: resolve_node_to_value has a strange interface, fix */
266
267		info->return_object =
268		    ACPI_CAST_PTR(union acpi_operand_object, info->node);
269
270		status =
271		    acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
272						  (struct acpi_namespace_node,
273						   &info->return_object), NULL);
274		acpi_ex_exit_interpreter();
275
276		if (ACPI_FAILURE(status)) {
277			info->return_object = NULL;
278			goto cleanup;
279		}
280
281		ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Returned object %p [%s]\n",
282				  info->return_object,
283				  acpi_ut_get_object_type_name(info->
284							       return_object)));
285
286		status = AE_CTRL_RETURN_VALUE;	/* Always has a "return value" */
287		break;
288	}
289
290	/*
291	 * For predefined names, check the return value against the ACPI
292	 * specification. Some incorrect return value types are repaired.
293	 */
294	(void)acpi_ns_check_return_value(info->node, info, info->param_count,
295					 status, &info->return_object);
296
297	/* Check if there is a return value that must be dealt with */
298
299	if (status == AE_CTRL_RETURN_VALUE) {
300
301		/* If caller does not want the return value, delete it */
302
303		if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
304			acpi_ut_remove_reference(info->return_object);
305			info->return_object = NULL;
306		}
307
308		/* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
309
310		status = AE_OK;
311	}
312
313	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
314			  "*** Completed evaluation of object %s ***\n",
315			  info->relative_pathname));
316
317cleanup:
318	/*
319	 * Namespace was unlocked by the handling acpi_ns* function, so we
320	 * just free the pathname and return
321	 */
322	ACPI_FREE(info->full_pathname);
323	info->full_pathname = NULL;
324	return_ACPI_STATUS(status);
325}
326
327/*******************************************************************************
328 *
329 * FUNCTION:    acpi_ns_exec_module_code_list
330 *
331 * PARAMETERS:  None
332 *
333 * RETURN:      None. Exceptions during method execution are ignored, since
334 *              we cannot abort a table load.
335 *
336 * DESCRIPTION: Execute all elements of the global module-level code list.
337 *              Each element is executed as a single control method.
338 *
339 ******************************************************************************/
340
341void acpi_ns_exec_module_code_list(void)
342{
343	union acpi_operand_object *prev;
344	union acpi_operand_object *next;
345	struct acpi_evaluate_info *info;
346	u32 method_count = 0;
347
348	ACPI_FUNCTION_TRACE(ns_exec_module_code_list);
349
350	/* Exit now if the list is empty */
351
352	next = acpi_gbl_module_code_list;
353	if (!next) {
354		return_VOID;
355	}
356
357	/* Allocate the evaluation information block */
358
359	info = ACPI_ALLOCATE(sizeof(struct acpi_evaluate_info));
360	if (!info) {
361		return_VOID;
362	}
363
364	/* Walk the list, executing each "method" */
365
366	while (next) {
367		prev = next;
368		next = next->method.mutex;
369
370		/* Clear the link field and execute the method */
371
372		prev->method.mutex = NULL;
373		acpi_ns_exec_module_code(prev, info);
374		method_count++;
375
376		/* Delete the (temporary) method object */
377
378		acpi_ut_remove_reference(prev);
379	}
380
381	ACPI_INFO((AE_INFO,
382		   "Executed %u blocks of module-level executable AML code",
383		   method_count));
384
385	ACPI_FREE(info);
386	acpi_gbl_module_code_list = NULL;
387	return_VOID;
388}
389
390/*******************************************************************************
391 *
392 * FUNCTION:    acpi_ns_exec_module_code
393 *
394 * PARAMETERS:  method_obj          - Object container for the module-level code
395 *              info                - Info block for method evaluation
396 *
397 * RETURN:      None. Exceptions during method execution are ignored, since
398 *              we cannot abort a table load.
399 *
400 * DESCRIPTION: Execute a control method containing a block of module-level
401 *              executable AML code. The control method is temporarily
402 *              installed to the root node, then evaluated.
403 *
404 ******************************************************************************/
405
406static void
407acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
408			 struct acpi_evaluate_info *info)
409{
410	union acpi_operand_object *parent_obj;
411	struct acpi_namespace_node *parent_node;
412	acpi_object_type type;
413	acpi_status status;
414
415	ACPI_FUNCTION_TRACE(ns_exec_module_code);
416
417	/*
418	 * Get the parent node. We cheat by using the next_object field
419	 * of the method object descriptor.
420	 */
421	parent_node = ACPI_CAST_PTR(struct acpi_namespace_node,
422				    method_obj->method.next_object);
423	type = acpi_ns_get_type(parent_node);
424
425	/*
426	 * Get the region handler and save it in the method object. We may need
427	 * this if an operation region declaration causes a _REG method to be run.
428	 *
429	 * We can't do this in acpi_ps_link_module_code because
430	 * acpi_gbl_root_node->Object is NULL at PASS1.
431	 */
432	if ((type == ACPI_TYPE_DEVICE) && parent_node->object) {
433		method_obj->method.dispatch.handler =
434		    parent_node->object->device.handler;
435	}
436
437	/* Must clear next_object (acpi_ns_attach_object needs the field) */
438
439	method_obj->method.next_object = NULL;
440
441	/* Initialize the evaluation information block */
442
443	memset(info, 0, sizeof(struct acpi_evaluate_info));
444	info->prefix_node = parent_node;
445
446	/*
447	 * Get the currently attached parent object. Add a reference, because the
448	 * ref count will be decreased when the method object is installed to
449	 * the parent node.
450	 */
451	parent_obj = acpi_ns_get_attached_object(parent_node);
452	if (parent_obj) {
453		acpi_ut_add_reference(parent_obj);
454	}
455
456	/* Install the method (module-level code) in the parent node */
457
458	status = acpi_ns_attach_object(parent_node, method_obj,
459				       ACPI_TYPE_METHOD);
460	if (ACPI_FAILURE(status)) {
461		goto exit;
462	}
463
464	/* Execute the parent node as a control method */
465
466	status = acpi_ns_evaluate(info);
467
468	ACPI_DEBUG_PRINT((ACPI_DB_INIT_NAMES,
469			  "Executed module-level code at %p\n",
470			  method_obj->method.aml_start));
471
472	/* Delete a possible implicit return value (in slack mode) */
473
474	if (info->return_object) {
475		acpi_ut_remove_reference(info->return_object);
476	}
477
478	/* Detach the temporary method object */
479
480	acpi_ns_detach_object(parent_node);
481
482	/* Restore the original parent object */
483
484	if (parent_obj) {
485		status = acpi_ns_attach_object(parent_node, parent_obj, type);
486	} else {
487		parent_node->type = (u8)type;
488	}
489
490exit:
491	if (parent_obj) {
492		acpi_ut_remove_reference(parent_obj);
493	}
494	return_VOID;
495}
496