1/******************************************************************************
2 *
3 * Module Name: nspredef - Validation of ACPI predefined methods and objects
4 *
5 *****************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2014, 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#define ACPI_CREATE_PREDEFINED_TABLE
45
46#include <acpi/acpi.h>
47#include "accommon.h"
48#include "acnamesp.h"
49#include "acpredef.h"
50
51#define _COMPONENT          ACPI_NAMESPACE
52ACPI_MODULE_NAME("nspredef")
53
54/*******************************************************************************
55 *
56 * This module validates predefined ACPI objects that appear in the namespace,
57 * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
58 * validation is to detect problems with BIOS-exposed predefined ACPI objects
59 * before the results are returned to the ACPI-related drivers.
60 *
61 * There are several areas that are validated:
62 *
63 *  1) The number of input arguments as defined by the method/object in the
64 *     ASL is validated against the ACPI specification.
65 *  2) The type of the return object (if any) is validated against the ACPI
66 *     specification.
67 *  3) For returned package objects, the count of package elements is
68 *     validated, as well as the type of each package element. Nested
69 *     packages are supported.
70 *
71 * For any problems found, a warning message is issued.
72 *
73 ******************************************************************************/
74/* Local prototypes */
75static acpi_status
76acpi_ns_check_reference(struct acpi_evaluate_info *info,
77			union acpi_operand_object *return_object);
78
79static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object);
80
81/*******************************************************************************
82 *
83 * FUNCTION:    acpi_ns_check_return_value
84 *
85 * PARAMETERS:  node            - Namespace node for the method/object
86 *              info            - Method execution information block
87 *              user_param_count - Number of parameters actually passed
88 *              return_status   - Status from the object evaluation
89 *              return_object_ptr - Pointer to the object returned from the
90 *                                evaluation of a method or object
91 *
92 * RETURN:      Status
93 *
94 * DESCRIPTION: Check the value returned from a predefined name.
95 *
96 ******************************************************************************/
97
98acpi_status
99acpi_ns_check_return_value(struct acpi_namespace_node *node,
100			   struct acpi_evaluate_info *info,
101			   u32 user_param_count,
102			   acpi_status return_status,
103			   union acpi_operand_object **return_object_ptr)
104{
105	acpi_status status;
106	const union acpi_predefined_info *predefined;
107
108	/* If not a predefined name, we cannot validate the return object */
109
110	predefined = info->predefined;
111	if (!predefined) {
112		return (AE_OK);
113	}
114
115	/*
116	 * If the method failed or did not actually return an object, we cannot
117	 * validate the return object
118	 */
119	if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
120		return (AE_OK);
121	}
122
123	/*
124	 * Return value validation and possible repair.
125	 *
126	 * 1) Don't perform return value validation/repair if this feature
127	 * has been disabled via a global option.
128	 *
129	 * 2) We have a return value, but if one wasn't expected, just exit,
130	 * this is not a problem. For example, if the "Implicit Return"
131	 * feature is enabled, methods will always return a value.
132	 *
133	 * 3) If the return value can be of any type, then we cannot perform
134	 * any validation, just exit.
135	 */
136	if (acpi_gbl_disable_auto_repair ||
137	    (!predefined->info.expected_btypes) ||
138	    (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
139		return (AE_OK);
140	}
141
142	/*
143	 * Check that the type of the main return object is what is expected
144	 * for this predefined name
145	 */
146	status = acpi_ns_check_object_type(info, return_object_ptr,
147					   predefined->info.expected_btypes,
148					   ACPI_NOT_PACKAGE_ELEMENT);
149	if (ACPI_FAILURE(status)) {
150		goto exit;
151	}
152
153	/*
154	 *
155	 * 4) If there is no return value and it is optional, just return
156	 * AE_OK (_WAK).
157	 */
158	if (!(*return_object_ptr)) {
159		goto exit;
160	}
161
162	/*
163	 * For returned Package objects, check the type of all sub-objects.
164	 * Note: Package may have been newly created by call above.
165	 */
166	if ((*return_object_ptr)->common.type == ACPI_TYPE_PACKAGE) {
167		info->parent_package = *return_object_ptr;
168		status = acpi_ns_check_package(info, return_object_ptr);
169		if (ACPI_FAILURE(status)) {
170
171			/* We might be able to fix some errors */
172
173			if ((status != AE_AML_OPERAND_TYPE) &&
174			    (status != AE_AML_OPERAND_VALUE)) {
175				goto exit;
176			}
177		}
178	}
179
180	/*
181	 * The return object was OK, or it was successfully repaired above.
182	 * Now make some additional checks such as verifying that package
183	 * objects are sorted correctly (if required) or buffer objects have
184	 * the correct data width (bytes vs. dwords). These repairs are
185	 * performed on a per-name basis, i.e., the code is specific to
186	 * particular predefined names.
187	 */
188	status = acpi_ns_complex_repairs(info, node, status, return_object_ptr);
189
190exit:
191	/*
192	 * If the object validation failed or if we successfully repaired one
193	 * or more objects, mark the parent node to suppress further warning
194	 * messages during the next evaluation of the same method/object.
195	 */
196	if (ACPI_FAILURE(status) || (info->return_flags & ACPI_OBJECT_REPAIRED)) {
197		node->flags |= ANOBJ_EVALUATED;
198	}
199
200	return (status);
201}
202
203/*******************************************************************************
204 *
205 * FUNCTION:    acpi_ns_check_object_type
206 *
207 * PARAMETERS:  info            - Method execution information block
208 *              return_object_ptr - Pointer to the object returned from the
209 *                                evaluation of a method or object
210 *              expected_btypes - Bitmap of expected return type(s)
211 *              package_index   - Index of object within parent package (if
212 *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
213 *                                otherwise)
214 *
215 * RETURN:      Status
216 *
217 * DESCRIPTION: Check the type of the return object against the expected object
218 *              type(s). Use of Btype allows multiple expected object types.
219 *
220 ******************************************************************************/
221
222acpi_status
223acpi_ns_check_object_type(struct acpi_evaluate_info *info,
224			  union acpi_operand_object **return_object_ptr,
225			  u32 expected_btypes, u32 package_index)
226{
227	union acpi_operand_object *return_object = *return_object_ptr;
228	acpi_status status = AE_OK;
229	char type_buffer[48];	/* Room for 5 types */
230
231	/* A Namespace node should not get here, but make sure */
232
233	if (return_object &&
234	    ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
235		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
236				      info->node_flags,
237				      "Invalid return type - Found a Namespace node [%4.4s] type %s",
238				      return_object->node.name.ascii,
239				      acpi_ut_get_type_name(return_object->node.
240							    type)));
241		return (AE_AML_OPERAND_TYPE);
242	}
243
244	/*
245	 * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
246	 * The bitmapped type allows multiple possible return types.
247	 *
248	 * Note, the cases below must handle all of the possible types returned
249	 * from all of the predefined names (including elements of returned
250	 * packages)
251	 */
252	info->return_btype = acpi_ns_get_bitmapped_type(return_object);
253	if (info->return_btype == ACPI_RTYPE_ANY) {
254
255		/* Not one of the supported objects, must be incorrect */
256		goto type_error_exit;
257	}
258
259	/* For reference objects, check that the reference type is correct */
260
261	if ((info->return_btype & expected_btypes) == ACPI_RTYPE_REFERENCE) {
262		status = acpi_ns_check_reference(info, return_object);
263		return (status);
264	}
265
266	/* Attempt simple repair of the returned object if necessary */
267
268	status = acpi_ns_simple_repair(info, expected_btypes,
269				       package_index, return_object_ptr);
270	if (ACPI_SUCCESS(status)) {
271		return (AE_OK);	/* Successful repair */
272	}
273
274type_error_exit:
275
276	/* Create a string with all expected types for this predefined object */
277
278	acpi_ut_get_expected_return_types(type_buffer, expected_btypes);
279
280	if (!return_object) {
281		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
282				      info->node_flags,
283				      "Expected return object of type %s",
284				      type_buffer));
285	} else if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
286		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
287				      info->node_flags,
288				      "Return type mismatch - found %s, expected %s",
289				      acpi_ut_get_object_type_name
290				      (return_object), type_buffer));
291	} else {
292		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
293				      info->node_flags,
294				      "Return Package type mismatch at index %u - "
295				      "found %s, expected %s", package_index,
296				      acpi_ut_get_object_type_name
297				      (return_object), type_buffer));
298	}
299
300	return (AE_AML_OPERAND_TYPE);
301}
302
303/*******************************************************************************
304 *
305 * FUNCTION:    acpi_ns_check_reference
306 *
307 * PARAMETERS:  info            - Method execution information block
308 *              return_object   - Object returned from the evaluation of a
309 *                                method or object
310 *
311 * RETURN:      Status
312 *
313 * DESCRIPTION: Check a returned reference object for the correct reference
314 *              type. The only reference type that can be returned from a
315 *              predefined method is a named reference. All others are invalid.
316 *
317 ******************************************************************************/
318
319static acpi_status
320acpi_ns_check_reference(struct acpi_evaluate_info *info,
321			union acpi_operand_object *return_object)
322{
323
324	/*
325	 * Check the reference object for the correct reference type (opcode).
326	 * The only type of reference that can be converted to an union acpi_object is
327	 * a reference to a named object (reference class: NAME)
328	 */
329	if (return_object->reference.class == ACPI_REFCLASS_NAME) {
330		return (AE_OK);
331	}
332
333	ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname, info->node_flags,
334			      "Return type mismatch - unexpected reference object type [%s] %2.2X",
335			      acpi_ut_get_reference_name(return_object),
336			      return_object->reference.class));
337
338	return (AE_AML_OPERAND_TYPE);
339}
340
341/*******************************************************************************
342 *
343 * FUNCTION:    acpi_ns_get_bitmapped_type
344 *
345 * PARAMETERS:  return_object   - Object returned from method/obj evaluation
346 *
347 * RETURN:      Object return type. ACPI_RTYPE_ANY indicates that the object
348 *              type is not supported. ACPI_RTYPE_NONE indicates that no
349 *              object was returned (return_object is NULL).
350 *
351 * DESCRIPTION: Convert object type into a bitmapped object return type.
352 *
353 ******************************************************************************/
354
355static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object)
356{
357	u32 return_btype;
358
359	if (!return_object) {
360		return (ACPI_RTYPE_NONE);
361	}
362
363	/* Map acpi_object_type to internal bitmapped type */
364
365	switch (return_object->common.type) {
366	case ACPI_TYPE_INTEGER:
367
368		return_btype = ACPI_RTYPE_INTEGER;
369		break;
370
371	case ACPI_TYPE_BUFFER:
372
373		return_btype = ACPI_RTYPE_BUFFER;
374		break;
375
376	case ACPI_TYPE_STRING:
377
378		return_btype = ACPI_RTYPE_STRING;
379		break;
380
381	case ACPI_TYPE_PACKAGE:
382
383		return_btype = ACPI_RTYPE_PACKAGE;
384		break;
385
386	case ACPI_TYPE_LOCAL_REFERENCE:
387
388		return_btype = ACPI_RTYPE_REFERENCE;
389		break;
390
391	default:
392
393		/* Not one of the supported objects, must be incorrect */
394
395		return_btype = ACPI_RTYPE_ANY;
396		break;
397	}
398
399	return (return_btype);
400}
401