LXR linux/drivers/acpi/acpica/exstore.c

   1/******************************************************************************
   2 *
   3 * Module Name: exstore - AML Interpreter object store support
   4 *
   5 *****************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2011, 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
  52ACPI_MODULE_NAME("exstore")
  53
  54/* Local prototypes */
  55static acpi_status
  56acpi_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 a 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
  80acpi_status
  81acpi_ex_store(union acpi_operand_object *source_desc,
  82              union acpi_operand_object *dest_desc,
  83              struct acpi_walk_state *walk_state)
  84{
  85        acpi_status status = AE_OK;
  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"));
  94                return_ACPI_STATUS(AE_AML_NO_OPERAND);
  95        }
  96
  97        /* dest_desc can be either a namespace node or an ACPI object */
  98
  99        if (ACPI_GET_DESCRIPTOR_TYPE(dest_desc) == ACPI_DESC_TYPE_NAMED) {
 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
 106                                                       acpi_namespace_node *)
 107                                                      dest_desc, walk_state,
 108                                                      ACPI_IMPLICIT_CONVERSION);
 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) {
 116        case ACPI_TYPE_LOCAL_REFERENCE:
 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) {
 124                        return_ACPI_STATUS(AE_OK);
 125                }
 126
 127                /*lint -fallthrough */
 128
 129        default:
 130
 131                /* Destination is not a Reference object */
 132
 133                ACPI_ERROR((AE_INFO,
 134                            "Target is not a Reference or Constant object - %s [%p]",
 135                            acpi_ut_get_object_type_name(dest_desc),
 136                            dest_desc));
 137
 138                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 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,
 157                                                      ACPI_IMPLICIT_CONVERSION);
 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 =
 175                    acpi_ds_store_object_to_local(ref_desc->reference.class,
 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                 */
 186                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 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
 221static acpi_status
 222acpi_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{
 226        acpi_status status = AE_OK;
 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 =
 262                            acpi_ut_copy_iobject_to_iobject(source_desc,
 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
 293        case ACPI_TYPE_BUFFER_FIELD:
 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)) {
 312                        return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 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
 339                        ACPI_ERROR((AE_INFO,
 340                                    "Source must be Integer/Buffer/String type, not %s",
 341                                    acpi_ut_get_object_type_name(source_desc)));
 342                        return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 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
 385acpi_status
 386acpi_ex_store_object_to_node(union acpi_operand_object *source_desc,
 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;
 394        acpi_object_type target_type;
 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) {
 436        case ACPI_TYPE_BUFFER_FIELD:
 437        case ACPI_TYPE_LOCAL_REGION_FIELD:
 438        case ACPI_TYPE_LOCAL_BANK_FIELD:
 439        case ACPI_TYPE_LOCAL_INDEX_FIELD:
 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
 478                        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 479                                          "Store %s into %s via Convert/Attach\n",
 480                                          acpi_ut_get_object_type_name
 481                                          (source_desc),
 482                                          acpi_ut_get_object_type_name
 483                                          (new_desc)));
 484                }
 485                break;
 486
 487        default:
 488
 489                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 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}
 503