drivers/acpi/acpica/nseval.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: nseval - Object evaluation, includes control method execution
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2013, 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
  51 ACPI_MODULE_NAME("nseval")
  52
  53 /* Local prototypes */
  54 static void
  55 acpi_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:
  63  *                  prefix_node     - Prefix or Method/Object Node to execute
  64  *                  relative_path   - Name of method to execute, If NULL, the
  65  *                                    Node is the object to execute
  66  *                  parameters      - List of parameters to pass to the method,
  67  *                                    terminated by NULL. Params itself may be
  68  *                                    NULL if no parameters are being passed.
  69  *                  return_object   - Where to put method's return value (if
  70  *                                    any). If NULL, no value is returned.
  71  *                  parameter_type  - Type of Parameter list
  72  *                  return_object   - Where to put method's return value (if
  73  *                                    any). If NULL, no value is returned.
  74  *                  flags           - ACPI_IGNORE_RETURN_VALUE to delete return
  75  *
  76  * RETURN:      Status
  77  *
  78  * DESCRIPTION: Execute a control method or return the current value of an
  79  *              ACPI namespace object.
  80  *
  81  * MUTEX:       Locks interpreter
  82  *
  83  ******************************************************************************/
  84
  85 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
  86 {
  87         acpi_status status;
  88
  89         ACPI_FUNCTION_TRACE(ns_evaluate);
  90
  91         if (!info) {
  92                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  93         }
  94
  95         if (!info->node) {
  96                 /*
  97                  * Get the actual namespace node for the target object if we
  98                  * need to. Handles these cases:
  99                  *
 100                  * 1) Null node, valid pathname from root (absolute path)
 101                  * 2) Node and valid pathname (path relative to Node)
 102                  * 3) Node, Null pathname
 103                  */
 104                 status =
 105                     acpi_ns_get_node(info->prefix_node, info->relative_pathname,
 106                                      ACPI_NS_NO_UPSEARCH, &info->node);
 107                 if (ACPI_FAILURE(status)) {
 108                         return_ACPI_STATUS(status);
 109                 }
 110         }
 111
 112         /*
 113          * For a method alias, we must grab the actual method node so that
 114          * proper scoping context will be established before execution.
 115          */
 116         if (acpi_ns_get_type(info->node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) {
 117                 info->node =
 118                     ACPI_CAST_PTR(struct acpi_namespace_node,
 119                                   info->node->object);
 120         }
 121
 122         /* Complete the info block initialization */
 123
 124         info->return_object = NULL;
 125         info->node_flags = info->node->flags;
 126         info->obj_desc = acpi_ns_get_attached_object(info->node);
 127
 128         ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n",
 129                           info->relative_pathname, info->node,
 130                           acpi_ns_get_attached_object(info->node)));
 131
 132         /* Get info if we have a predefined name (_HID, etc.) */
 133
 134         info->predefined =
 135             acpi_ut_match_predefined_method(info->node->name.ascii);
 136
 137         /* Get the full pathname to the object, for use in warning messages */
 138
 139         info->full_pathname = acpi_ns_get_external_pathname(info->node);
 140         if (!info->full_pathname) {
 141                 return_ACPI_STATUS(AE_NO_MEMORY);
 142         }
 143
 144         /* Count the number of arguments being passed in */
 145
 146         info->param_count = 0;
 147         if (info->parameters) {
 148                 while (info->parameters[info->param_count]) {
 149                         info->param_count++;
 150                 }
 151
 152                 /* Warn on impossible argument count */
 153
 154                 if (info->param_count > ACPI_METHOD_NUM_ARGS) {
 155                         ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
 156                                               ACPI_WARN_ALWAYS,
 157                                               "Excess arguments (%u) - using only %u",
 158                                               info->param_count,
 159                                               ACPI_METHOD_NUM_ARGS));
 160
 161                         info->param_count = ACPI_METHOD_NUM_ARGS;
 162                 }
 163         }
 164
 165         /*
 166          * For predefined names: Check that the declared argument count
 167          * matches the ACPI spec -- otherwise this is a BIOS error.
 168          */
 169         acpi_ns_check_acpi_compliance(info->full_pathname, info->node,
 170                                       info->predefined);
 171
 172         /*
 173          * For all names: Check that the incoming argument count for
 174          * this method/object matches the actual ASL/AML definition.
 175          */
 176         acpi_ns_check_argument_count(info->full_pathname, info->node,
 177                                      info->param_count, info->predefined);
 178
 179         /* For predefined names: Typecheck all incoming arguments */
 180
 181         acpi_ns_check_argument_types(info);
 182
 183         /*
 184          * Three major evaluation cases:
 185          *
 186          * 1) Object types that cannot be evaluated by definition
 187          * 2) The object is a control method -- execute it
 188          * 3) The object is not a method -- just return it's current value
 189          */
 190         switch (acpi_ns_get_type(info->node)) {
 191         case ACPI_TYPE_DEVICE:
 192         case ACPI_TYPE_EVENT:
 193         case ACPI_TYPE_MUTEX:
 194         case ACPI_TYPE_REGION:
 195         case ACPI_TYPE_THERMAL:
 196         case ACPI_TYPE_LOCAL_SCOPE:
 197                 /*
 198                  * 1) Disallow evaluation of certain object types. For these,
 199                  *    object evaluation is undefined and not supported.
 200                  */
 201                 ACPI_ERROR((AE_INFO,
 202                             "%s: Evaluation of object type [%s] is not supported",
 203                             info->full_pathname,
 204                             acpi_ut_get_type_name(info->node->type)));
 205
 206                 status = AE_TYPE;
 207                 goto cleanup;
 208
 209         case ACPI_TYPE_METHOD:
 210                 /*
 211                  * 2) Object is a control method - execute it
 212                  */
 213
 214                 /* Verify that there is a method object associated with this node */
 215
 216                 if (!info->obj_desc) {
 217                         ACPI_ERROR((AE_INFO,
 218                                     "%s: Method has no attached sub-object",
 219                                     info->full_pathname));
 220                         status = AE_NULL_OBJECT;
 221                         goto cleanup;
 222                 }
 223
 224                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 225                                   "**** Execute method [%s] at AML address %p length %X\n",
 226                                   info->full_pathname,
 227                                   info->obj_desc->method.aml_start + 1,
 228                                   info->obj_desc->method.aml_length - 1));
 229
 230                 /*
 231                  * Any namespace deletion must acquire both the namespace and
 232                  * interpreter locks to ensure that no thread is using the portion of
 233                  * the namespace that is being deleted.
 234                  *
 235                  * Execute the method via the interpreter. The interpreter is locked
 236                  * here before calling into the AML parser
 237                  */
 238                 acpi_ex_enter_interpreter();
 239                 status = acpi_ps_execute_method(info);
 240                 acpi_ex_exit_interpreter();
 241                 break;
 242
 243         default:
 244                 /*
 245                  * 3) All other non-method objects -- get the current object value
 246                  */
 247
 248                 /*
 249                  * Some objects require additional resolution steps (e.g., the Node
 250                  * may be a field that must be read, etc.) -- we can't just grab
 251                  * the object out of the node.
 252                  *
 253                  * Use resolve_node_to_value() to get the associated value.
 254                  *
 255                  * NOTE: we can get away with passing in NULL for a walk state because
 256                  * the Node is guaranteed to not be a reference to either a method
 257                  * local or a method argument (because this interface is never called
 258                  * from a running method.)
 259                  *
 260                  * Even though we do not directly invoke the interpreter for object
 261                  * resolution, we must lock it because we could access an op_region.
 262                  * The op_region access code assumes that the interpreter is locked.
 263                  */
 264                 acpi_ex_enter_interpreter();
 265
 266                 /* TBD: resolve_node_to_value has a strange interface, fix */
 267
 268                 info->return_object =
 269                     ACPI_CAST_PTR(union acpi_operand_object, info->node);
 270
 271                 status =
 272                     acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
 273                                                   (struct acpi_namespace_node,
 274                                                    &info->return_object), NULL);
 275                 acpi_ex_exit_interpreter();
 276
 277                 if (ACPI_FAILURE(status)) {
 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
 317 cleanup:
 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
 341 void 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
 406 static void
 407 acpi_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         ACPI_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, "Executed module-level code at %p\n",
 469                           method_obj->method.aml_start));
 470
 471         /* Delete a possible implicit return value (in slack mode) */
 472
 473         if (info->return_object) {
 474                 acpi_ut_remove_reference(info->return_object);
 475         }
 476
 477         /* Detach the temporary method object */
 478
 479         acpi_ns_detach_object(parent_node);
 480
 481         /* Restore the original parent object */
 482
 483         if (parent_obj) {
 484                 status = acpi_ns_attach_object(parent_node, parent_obj, type);
 485         } else {
 486                 parent_node->type = (u8)type;
 487         }
 488
 489 exit:
 490         if (parent_obj) {
 491                 acpi_ut_remove_reference(parent_obj);
 492         }
 493         return_VOID;
 494 }