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exstore.c
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1 /******************************************************************************
2  *
3  * Module Name: exstore - AML Interpreter object store support
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2012, 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 "acdispat.h"
47 #include "acinterp.h"
48 #include "amlcode.h"
49 #include "acnamesp.h"
50 
51 #define _COMPONENT ACPI_EXECUTER
52 ACPI_MODULE_NAME("exstore")
53 
54 /* Local prototypes */
55 static acpi_status
56 acpi_ex_store_object_to_index(union acpi_operand_object *val_desc,
57  union acpi_operand_object *dest_desc,
58  struct acpi_walk_state *walk_state);
59 
60 /*******************************************************************************
61  *
62  * FUNCTION: acpi_ex_store
63  *
64  * PARAMETERS: *source_desc - Value to be stored
65  * *dest_desc - Where to store it. Must be an NS node
66  * or union acpi_operand_object of type
67  * Reference;
68  * walk_state - Current walk state
69  *
70  * RETURN: Status
71  *
72  * DESCRIPTION: Store the value described by source_desc into the location
73  * described by dest_desc. Called by various interpreter
74  * functions to store the result of an operation into
75  * the destination operand -- not just simply the actual "Store"
76  * ASL operator.
77  *
78  ******************************************************************************/
79 
82  union acpi_operand_object *dest_desc,
83  struct acpi_walk_state *walk_state)
84 {
86  union acpi_operand_object *ref_desc = dest_desc;
87 
88  ACPI_FUNCTION_TRACE_PTR(ex_store, dest_desc);
89 
90  /* Validate parameters */
91 
92  if (!source_desc || !dest_desc) {
93  ACPI_ERROR((AE_INFO, "Null parameter"));
95  }
96 
97  /* dest_desc can be either a namespace node or an ACPI object */
98 
100  /*
101  * Dest is a namespace node,
102  * Storing an object into a Named node.
103  */
104  status = acpi_ex_store_object_to_node(source_desc,
105  (struct
107  dest_desc, walk_state,
109 
110  return_ACPI_STATUS(status);
111  }
112 
113  /* Destination object must be a Reference or a Constant object */
114 
115  switch (dest_desc->common.type) {
117  break;
118 
119  case ACPI_TYPE_INTEGER:
120 
121  /* Allow stores to Constants -- a Noop as per ACPI spec */
122 
123  if (dest_desc->common.flags & AOPOBJ_AML_CONSTANT) {
125  }
126 
127  /*lint -fallthrough */
128 
129  default:
130 
131  /* Destination is not a Reference object */
132 
134  "Target is not a Reference or Constant object - %s [%p]",
135  acpi_ut_get_object_type_name(dest_desc),
136  dest_desc));
137 
139  }
140 
141  /*
142  * Examine the Reference class. These cases are handled:
143  *
144  * 1) Store to Name (Change the object associated with a name)
145  * 2) Store to an indexed area of a Buffer or Package
146  * 3) Store to a Method Local or Arg
147  * 4) Store to the debug object
148  */
149  switch (ref_desc->reference.class) {
150  case ACPI_REFCLASS_REFOF:
151 
152  /* Storing an object into a Name "container" */
153 
154  status = acpi_ex_store_object_to_node(source_desc,
155  ref_desc->reference.
156  object, walk_state,
158  break;
159 
160  case ACPI_REFCLASS_INDEX:
161 
162  /* Storing to an Index (pointer into a packager or buffer) */
163 
164  status =
165  acpi_ex_store_object_to_index(source_desc, ref_desc,
166  walk_state);
167  break;
168 
169  case ACPI_REFCLASS_LOCAL:
170  case ACPI_REFCLASS_ARG:
171 
172  /* Store to a method local/arg */
173 
174  status =
176  ref_desc->reference.value,
177  source_desc, walk_state);
178  break;
179 
180  case ACPI_REFCLASS_DEBUG:
181 
182  /*
183  * Storing to the Debug object causes the value stored to be
184  * displayed and otherwise has no effect -- see ACPI Specification
185  */
187  "**** Write to Debug Object: Object %p %s ****:\n\n",
188  source_desc,
189  acpi_ut_get_object_type_name(source_desc)));
190 
191  ACPI_DEBUG_OBJECT(source_desc, 0, 0);
192  break;
193 
194  default:
195 
196  ACPI_ERROR((AE_INFO, "Unknown Reference Class 0x%2.2X",
197  ref_desc->reference.class));
198  ACPI_DUMP_ENTRY(ref_desc, ACPI_LV_INFO);
199 
200  status = AE_AML_INTERNAL;
201  break;
202  }
203 
204  return_ACPI_STATUS(status);
205 }
206 
207 /*******************************************************************************
208  *
209  * FUNCTION: acpi_ex_store_object_to_index
210  *
211  * PARAMETERS: *source_desc - Value to be stored
212  * *dest_desc - Named object to receive the value
213  * walk_state - Current walk state
214  *
215  * RETURN: Status
216  *
217  * DESCRIPTION: Store the object to indexed Buffer or Package element
218  *
219  ******************************************************************************/
220 
221 static acpi_status
222 acpi_ex_store_object_to_index(union acpi_operand_object *source_desc,
223  union acpi_operand_object *index_desc,
224  struct acpi_walk_state *walk_state)
225 {
227  union acpi_operand_object *obj_desc;
228  union acpi_operand_object *new_desc;
229  u8 value = 0;
230  u32 i;
231 
232  ACPI_FUNCTION_TRACE(ex_store_object_to_index);
233 
234  /*
235  * Destination must be a reference pointer, and
236  * must point to either a buffer or a package
237  */
238  switch (index_desc->reference.target_type) {
239  case ACPI_TYPE_PACKAGE:
240  /*
241  * Storing to a package element. Copy the object and replace
242  * any existing object with the new object. No implicit
243  * conversion is performed.
244  *
245  * The object at *(index_desc->Reference.Where) is the
246  * element within the package that is to be modified.
247  * The parent package object is at index_desc->Reference.Object
248  */
249  obj_desc = *(index_desc->reference.where);
250 
251  if (source_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE &&
252  source_desc->reference.class == ACPI_REFCLASS_TABLE) {
253 
254  /* This is a DDBHandle, just add a reference to it */
255 
256  acpi_ut_add_reference(source_desc);
257  new_desc = source_desc;
258  } else {
259  /* Normal object, copy it */
260 
261  status =
263  &new_desc,
264  walk_state);
265  if (ACPI_FAILURE(status)) {
266  return_ACPI_STATUS(status);
267  }
268  }
269 
270  if (obj_desc) {
271 
272  /* Decrement reference count by the ref count of the parent package */
273 
274  for (i = 0; i < ((union acpi_operand_object *)
275  index_desc->reference.object)->common.
276  reference_count; i++) {
277  acpi_ut_remove_reference(obj_desc);
278  }
279  }
280 
281  *(index_desc->reference.where) = new_desc;
282 
283  /* Increment ref count by the ref count of the parent package-1 */
284 
285  for (i = 1; i < ((union acpi_operand_object *)
286  index_desc->reference.object)->common.
287  reference_count; i++) {
288  acpi_ut_add_reference(new_desc);
289  }
290 
291  break;
292 
294 
295  /*
296  * Store into a Buffer or String (not actually a real buffer_field)
297  * at a location defined by an Index.
298  *
299  * The first 8-bit element of the source object is written to the
300  * 8-bit Buffer location defined by the Index destination object,
301  * according to the ACPI 2.0 specification.
302  */
303 
304  /*
305  * Make sure the target is a Buffer or String. An error should
306  * not happen here, since the reference_object was constructed
307  * by the INDEX_OP code.
308  */
309  obj_desc = index_desc->reference.object;
310  if ((obj_desc->common.type != ACPI_TYPE_BUFFER) &&
311  (obj_desc->common.type != ACPI_TYPE_STRING)) {
313  }
314 
315  /*
316  * The assignment of the individual elements will be slightly
317  * different for each source type.
318  */
319  switch (source_desc->common.type) {
320  case ACPI_TYPE_INTEGER:
321 
322  /* Use the least-significant byte of the integer */
323 
324  value = (u8) (source_desc->integer.value);
325  break;
326 
327  case ACPI_TYPE_BUFFER:
328  case ACPI_TYPE_STRING:
329 
330  /* Note: Takes advantage of common string/buffer fields */
331 
332  value = source_desc->buffer.pointer[0];
333  break;
334 
335  default:
336 
337  /* All other types are invalid */
338 
340  "Source must be Integer/Buffer/String type, not %s",
341  acpi_ut_get_object_type_name(source_desc)));
343  }
344 
345  /* Store the source value into the target buffer byte */
346 
347  obj_desc->buffer.pointer[index_desc->reference.value] = value;
348  break;
349 
350  default:
351  ACPI_ERROR((AE_INFO, "Target is not a Package or BufferField"));
352  status = AE_AML_OPERAND_TYPE;
353  break;
354  }
355 
356  return_ACPI_STATUS(status);
357 }
358 
359 /*******************************************************************************
360  *
361  * FUNCTION: acpi_ex_store_object_to_node
362  *
363  * PARAMETERS: source_desc - Value to be stored
364  * node - Named object to receive the value
365  * walk_state - Current walk state
366  * implicit_conversion - Perform implicit conversion (yes/no)
367  *
368  * RETURN: Status
369  *
370  * DESCRIPTION: Store the object to the named object.
371  *
372  * The Assignment of an object to a named object is handled here
373  * The value passed in will replace the current value (if any)
374  * with the input value.
375  *
376  * When storing into an object the data is converted to the
377  * target object type then stored in the object. This means
378  * that the target object type (for an initialized target) will
379  * not be changed by a store operation.
380  *
381  * Assumes parameters are already validated.
382  *
383  ******************************************************************************/
384 
387  struct acpi_namespace_node *node,
388  struct acpi_walk_state *walk_state,
389  u8 implicit_conversion)
390 {
391  acpi_status status = AE_OK;
392  union acpi_operand_object *target_desc;
393  union acpi_operand_object *new_desc;
395 
396  ACPI_FUNCTION_TRACE_PTR(ex_store_object_to_node, source_desc);
397 
398  /* Get current type of the node, and object attached to Node */
399 
400  target_type = acpi_ns_get_type(node);
401  target_desc = acpi_ns_get_attached_object(node);
402 
403  ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Storing %p(%s) into node %p(%s)\n",
404  source_desc,
405  acpi_ut_get_object_type_name(source_desc), node,
406  acpi_ut_get_type_name(target_type)));
407 
408  /*
409  * Resolve the source object to an actual value
410  * (If it is a reference object)
411  */
412  status = acpi_ex_resolve_object(&source_desc, target_type, walk_state);
413  if (ACPI_FAILURE(status)) {
414  return_ACPI_STATUS(status);
415  }
416 
417  /* If no implicit conversion, drop into the default case below */
418 
419  if ((!implicit_conversion) ||
420  ((walk_state->opcode == AML_COPY_OP) &&
421  (target_type != ACPI_TYPE_LOCAL_REGION_FIELD) &&
422  (target_type != ACPI_TYPE_LOCAL_BANK_FIELD) &&
423  (target_type != ACPI_TYPE_LOCAL_INDEX_FIELD))) {
424  /*
425  * Force execution of default (no implicit conversion). Note:
426  * copy_object does not perform an implicit conversion, as per the ACPI
427  * spec -- except in case of region/bank/index fields -- because these
428  * objects must retain their original type permanently.
429  */
430  target_type = ACPI_TYPE_ANY;
431  }
432 
433  /* Do the actual store operation */
434 
435  switch (target_type) {
440 
441  /* For fields, copy the source data to the target field. */
442 
443  status = acpi_ex_write_data_to_field(source_desc, target_desc,
444  &walk_state->result_obj);
445  break;
446 
447  case ACPI_TYPE_INTEGER:
448  case ACPI_TYPE_STRING:
449  case ACPI_TYPE_BUFFER:
450 
451  /*
452  * These target types are all of type Integer/String/Buffer, and
453  * therefore support implicit conversion before the store.
454  *
455  * Copy and/or convert the source object to a new target object
456  */
457  status =
458  acpi_ex_store_object_to_object(source_desc, target_desc,
459  &new_desc, walk_state);
460  if (ACPI_FAILURE(status)) {
461  return_ACPI_STATUS(status);
462  }
463 
464  if (new_desc != target_desc) {
465  /*
466  * Store the new new_desc as the new value of the Name, and set
467  * the Name's type to that of the value being stored in it.
468  * source_desc reference count is incremented by attach_object.
469  *
470  * Note: This may change the type of the node if an explicit store
471  * has been performed such that the node/object type has been
472  * changed.
473  */
474  status =
475  acpi_ns_attach_object(node, new_desc,
476  new_desc->common.type);
477 
479  "Store %s into %s via Convert/Attach\n",
481  (source_desc),
483  (new_desc)));
484  }
485  break;
486 
487  default:
488 
490  "Storing %s (%p) directly into node (%p) with no implicit conversion\n",
491  acpi_ut_get_object_type_name(source_desc),
492  source_desc, node));
493 
494  /* No conversions for all other types. Just attach the source object */
495 
496  status = acpi_ns_attach_object(node, source_desc,
497  source_desc->common.type);
498  break;
499  }
500 
501  return_ACPI_STATUS(status);
502 }