drivers/acpi/acpica/nseval.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /*******************************************************************************
   3  *
   4  * Module Name: nseval - Object evaluation, includes control method execution
   5  *
   6  ******************************************************************************/
   7
   8 #include <acpi/acpi.h>
   9 #include "accommon.h"
  10 #include "acparser.h"
  11 #include "acinterp.h"
  12 #include "acnamesp.h"
  13
  14 #define _COMPONENT          ACPI_NAMESPACE
  15 ACPI_MODULE_NAME("nseval")
  16
  17 /* Local prototypes */
  18 static void
  19 acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
  20                          struct acpi_evaluate_info *info);
  21
  22 /*******************************************************************************
  23  *
  24  * FUNCTION:    acpi_ns_evaluate
  25  *
  26  * PARAMETERS:  info            - Evaluation info block, contains these fields
  27  *                                and more:
  28  *                  prefix_node     - Prefix or Method/Object Node to execute
  29  *                  relative_path   - Name of method to execute, If NULL, the
  30  *                                    Node is the object to execute
  31  *                  parameters      - List of parameters to pass to the method,
  32  *                                    terminated by NULL. Params itself may be
  33  *                                    NULL if no parameters are being passed.
  34  *                  parameter_type  - Type of Parameter list
  35  *                  return_object   - Where to put method's return value (if
  36  *                                    any). If NULL, no value is returned.
  37  *                  flags           - ACPI_IGNORE_RETURN_VALUE to delete return
  38  *
  39  * RETURN:      Status
  40  *
  41  * DESCRIPTION: Execute a control method or return the current value of an
  42  *              ACPI namespace object.
  43  *
  44  * MUTEX:       Locks interpreter
  45  *
  46  ******************************************************************************/
  47
  48 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
  49 {
  50         acpi_status status;
  51
  52         ACPI_FUNCTION_TRACE(ns_evaluate);
  53
  54         if (!info) {
  55                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  56         }
  57
  58         if (!info->node) {
  59                 /*
  60                  * Get the actual namespace node for the target object if we
  61                  * need to. Handles these cases:
  62                  *
  63                  * 1) Null node, valid pathname from root (absolute path)
  64                  * 2) Node and valid pathname (path relative to Node)
  65                  * 3) Node, Null pathname
  66                  */
  67                 status =
  68                     acpi_ns_get_node(info->prefix_node, info->relative_pathname,
  69                                      ACPI_NS_NO_UPSEARCH, &info->node);
  70                 if (ACPI_FAILURE(status)) {
  71                         return_ACPI_STATUS(status);
  72                 }
  73         }
  74
  75         /*
  76          * For a method alias, we must grab the actual method node so that
  77          * proper scoping context will be established before execution.
  78          */
  79         if (acpi_ns_get_type(info->node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) {
  80                 info->node =
  81                     ACPI_CAST_PTR(struct acpi_namespace_node,
  82                                   info->node->object);
  83         }
  84
  85         /* Complete the info block initialization */
  86
  87         info->return_object = NULL;
  88         info->node_flags = info->node->flags;
  89         info->obj_desc = acpi_ns_get_attached_object(info->node);
  90
  91         ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n",
  92                           info->relative_pathname, info->node,
  93                           acpi_ns_get_attached_object(info->node)));
  94
  95         /* Get info if we have a predefined name (_HID, etc.) */
  96
  97         info->predefined =
  98             acpi_ut_match_predefined_method(info->node->name.ascii);
  99
 100         /* Get the full pathname to the object, for use in warning messages */
 101
 102         info->full_pathname = acpi_ns_get_normalized_pathname(info->node, TRUE);
 103         if (!info->full_pathname) {
 104                 return_ACPI_STATUS(AE_NO_MEMORY);
 105         }
 106
 107         /* Count the number of arguments being passed in */
 108
 109         info->param_count = 0;
 110         if (info->parameters) {
 111                 while (info->parameters[info->param_count]) {
 112                         info->param_count++;
 113                 }
 114
 115                 /* Warn on impossible argument count */
 116
 117                 if (info->param_count > ACPI_METHOD_NUM_ARGS) {
 118                         ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
 119                                               ACPI_WARN_ALWAYS,
 120                                               "Excess arguments (%u) - using only %u",
 121                                               info->param_count,
 122                                               ACPI_METHOD_NUM_ARGS));
 123
 124                         info->param_count = ACPI_METHOD_NUM_ARGS;
 125                 }
 126         }
 127
 128         /*
 129          * For predefined names: Check that the declared argument count
 130          * matches the ACPI spec -- otherwise this is a BIOS error.
 131          */
 132         acpi_ns_check_acpi_compliance(info->full_pathname, info->node,
 133                                       info->predefined);
 134
 135         /*
 136          * For all names: Check that the incoming argument count for
 137          * this method/object matches the actual ASL/AML definition.
 138          */
 139         acpi_ns_check_argument_count(info->full_pathname, info->node,
 140                                      info->param_count, info->predefined);
 141
 142         /* For predefined names: Typecheck all incoming arguments */
 143
 144         acpi_ns_check_argument_types(info);
 145
 146         /*
 147          * Three major evaluation cases:
 148          *
 149          * 1) Object types that cannot be evaluated by definition
 150          * 2) The object is a control method -- execute it
 151          * 3) The object is not a method -- just return it's current value
 152          */
 153         switch (acpi_ns_get_type(info->node)) {
 154         case ACPI_TYPE_ANY:
 155         case ACPI_TYPE_DEVICE:
 156         case ACPI_TYPE_EVENT:
 157         case ACPI_TYPE_MUTEX:
 158         case ACPI_TYPE_REGION:
 159         case ACPI_TYPE_THERMAL:
 160         case ACPI_TYPE_LOCAL_SCOPE:
 161                 /*
 162                  * 1) Disallow evaluation of these object types. For these,
 163                  *    object evaluation is undefined.
 164                  */
 165                 ACPI_ERROR((AE_INFO,
 166                             "%s: This object type [%s] "
 167                             "never contains data and cannot be evaluated",
 168                             info->full_pathname,
 169                             acpi_ut_get_type_name(info->node->type)));
 170
 171                 status = AE_TYPE;
 172                 goto cleanup;
 173
 174         case ACPI_TYPE_METHOD:
 175                 /*
 176                  * 2) Object is a control method - execute it
 177                  */
 178
 179                 /* Verify that there is a method object associated with this node */
 180
 181                 if (!info->obj_desc) {
 182                         ACPI_ERROR((AE_INFO,
 183                                     "%s: Method has no attached sub-object",
 184                                     info->full_pathname));
 185                         status = AE_NULL_OBJECT;
 186                         goto cleanup;
 187                 }
 188
 189                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 190                                   "**** Execute method [%s] at AML address %p length %X\n",
 191                                   info->full_pathname,
 192                                   info->obj_desc->method.aml_start + 1,
 193                                   info->obj_desc->method.aml_length - 1));
 194
 195                 /*
 196                  * Any namespace deletion must acquire both the namespace and
 197                  * interpreter locks to ensure that no thread is using the portion of
 198                  * the namespace that is being deleted.
 199                  *
 200                  * Execute the method via the interpreter. The interpreter is locked
 201                  * here before calling into the AML parser
 202                  */
 203                 acpi_ex_enter_interpreter();
 204                 status = acpi_ps_execute_method(info);
 205                 acpi_ex_exit_interpreter();
 206                 break;
 207
 208         default:
 209                 /*
 210                  * 3) All other non-method objects -- get the current object value
 211                  */
 212
 213                 /*
 214                  * Some objects require additional resolution steps (e.g., the Node
 215                  * may be a field that must be read, etc.) -- we can't just grab
 216                  * the object out of the node.
 217                  *
 218                  * Use resolve_node_to_value() to get the associated value.
 219                  *
 220                  * NOTE: we can get away with passing in NULL for a walk state because
 221                  * the Node is guaranteed to not be a reference to either a method
 222                  * local or a method argument (because this interface is never called
 223                  * from a running method.)
 224                  *
 225                  * Even though we do not directly invoke the interpreter for object
 226                  * resolution, we must lock it because we could access an op_region.
 227                  * The op_region access code assumes that the interpreter is locked.
 228                  */
 229                 acpi_ex_enter_interpreter();
 230
 231                 /* TBD: resolve_node_to_value has a strange interface, fix */
 232
 233                 info->return_object =
 234                     ACPI_CAST_PTR(union acpi_operand_object, info->node);
 235
 236                 status =
 237                     acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
 238                                                   (struct acpi_namespace_node,
 239                                                    &info->return_object), NULL);
 240                 acpi_ex_exit_interpreter();
 241
 242                 if (ACPI_FAILURE(status)) {
 243                         info->return_object = NULL;
 244                         goto cleanup;
 245                 }
 246
 247                 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Returned object %p [%s]\n",
 248                                   info->return_object,
 249                                   acpi_ut_get_object_type_name(info->
 250                                                                return_object)));
 251
 252                 status = AE_CTRL_RETURN_VALUE;  /* Always has a "return value" */
 253                 break;
 254         }
 255
 256         /*
 257          * For predefined names, check the return value against the ACPI
 258          * specification. Some incorrect return value types are repaired.
 259          */
 260         (void)acpi_ns_check_return_value(info->node, info, info->param_count,
 261                                          status, &info->return_object);
 262
 263         /* Check if there is a return value that must be dealt with */
 264
 265         if (status == AE_CTRL_RETURN_VALUE) {
 266
 267                 /* If caller does not want the return value, delete it */
 268
 269                 if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
 270                         acpi_ut_remove_reference(info->return_object);
 271                         info->return_object = NULL;
 272                 }
 273
 274                 /* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
 275
 276                 status = AE_OK;
 277         } else if (ACPI_FAILURE(status)) {
 278
 279                 /* If return_object exists, delete it */
 280
 281                 if (info->return_object) {
 282                         acpi_ut_remove_reference(info->return_object);
 283                         info->return_object = NULL;
 284                 }
 285         }
 286
 287         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
 288                           "*** Completed evaluation of object %s ***\n",
 289                           info->relative_pathname));
 290
 291 cleanup:
 292         /*
 293          * Namespace was unlocked by the handling acpi_ns* function, so we
 294          * just free the pathname and return
 295          */
 296         ACPI_FREE(info->full_pathname);
 297         info->full_pathname = NULL;
 298         return_ACPI_STATUS(status);
 299 }
 300
 301 /*******************************************************************************
 302  *
 303  * FUNCTION:    acpi_ns_exec_module_code_list
 304  *
 305  * PARAMETERS:  None
 306  *
 307  * RETURN:      None. Exceptions during method execution are ignored, since
 308  *              we cannot abort a table load.
 309  *
 310  * DESCRIPTION: Execute all elements of the global module-level code list.
 311  *              Each element is executed as a single control method.
 312  *
 313  * NOTE: With this option enabled, each block of detected executable AML
 314  * code that is outside of any control method is wrapped with a temporary
 315  * control method object and placed on a global list. The methods on this
 316  * list are executed below.
 317  *
 318  * This function executes the module-level code for all tables only after
 319  * all of the tables have been loaded. It is a legacy option and is
 320  * not compatible with other ACPI implementations. See acpi_ns_load_table.
 321  *
 322  * This function will be removed when the legacy option is removed.
 323  *
 324  ******************************************************************************/
 325
 326 void acpi_ns_exec_module_code_list(void)
 327 {
 328         union acpi_operand_object *prev;
 329         union acpi_operand_object *next;
 330         struct acpi_evaluate_info *info;
 331         u32 method_count = 0;
 332
 333         ACPI_FUNCTION_TRACE(ns_exec_module_code_list);
 334
 335         /* Exit now if the list is empty */
 336
 337         next = acpi_gbl_module_code_list;
 338         if (!next) {
 339                 ACPI_DEBUG_PRINT((ACPI_DB_INIT_NAMES,
 340                                   "Legacy MLC block list is empty\n"));
 341
 342                 return_VOID;
 343         }
 344
 345         /* Allocate the evaluation information block */
 346
 347         info = ACPI_ALLOCATE(sizeof(struct acpi_evaluate_info));
 348         if (!info) {
 349                 return_VOID;
 350         }
 351
 352         /* Walk the list, executing each "method" */
 353
 354         while (next) {
 355                 prev = next;
 356                 next = next->method.mutex;
 357
 358                 /* Clear the link field and execute the method */
 359
 360                 prev->method.mutex = NULL;
 361                 acpi_ns_exec_module_code(prev, info);
 362                 method_count++;
 363
 364                 /* Delete the (temporary) method object */
 365
 366                 acpi_ut_remove_reference(prev);
 367         }
 368
 369         ACPI_INFO(("Executed %u blocks of module-level executable AML code",
 370                    method_count));
 371
 372         ACPI_FREE(info);
 373         acpi_gbl_module_code_list = NULL;
 374         return_VOID;
 375 }
 376
 377 /*******************************************************************************
 378  *
 379  * FUNCTION:    acpi_ns_exec_module_code
 380  *
 381  * PARAMETERS:  method_obj          - Object container for the module-level code
 382  *              info                - Info block for method evaluation
 383  *
 384  * RETURN:      None. Exceptions during method execution are ignored, since
 385  *              we cannot abort a table load.
 386  *
 387  * DESCRIPTION: Execute a control method containing a block of module-level
 388  *              executable AML code. The control method is temporarily
 389  *              installed to the root node, then evaluated.
 390  *
 391  ******************************************************************************/
 392
 393 static void
 394 acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
 395                          struct acpi_evaluate_info *info)
 396 {
 397         union acpi_operand_object *parent_obj;
 398         struct acpi_namespace_node *parent_node;
 399         acpi_object_type type;
 400         acpi_status status;
 401
 402         ACPI_FUNCTION_TRACE(ns_exec_module_code);
 403
 404         /*
 405          * Get the parent node. We cheat by using the next_object field
 406          * of the method object descriptor.
 407          */
 408         parent_node =
 409             ACPI_CAST_PTR(struct acpi_namespace_node,
 410                                     method_obj->method.next_object);
 411         type = acpi_ns_get_type(parent_node);
 412
 413         /*
 414          * Get the region handler and save it in the method object. We may need
 415          * this if an operation region declaration causes a _REG method to be run.
 416          *
 417          * We can't do this in acpi_ps_link_module_code because
 418          * acpi_gbl_root_node->Object is NULL at PASS1.
 419          */
 420         if ((type == ACPI_TYPE_DEVICE) && parent_node->object) {
 421                 method_obj->method.dispatch.handler =
 422                     parent_node->object->device.handler;
 423         }
 424
 425         /* Must clear next_object (acpi_ns_attach_object needs the field) */
 426
 427         method_obj->method.next_object = NULL;
 428
 429         /* Initialize the evaluation information block */
 430
 431         memset(info, 0, sizeof(struct acpi_evaluate_info));
 432         info->prefix_node = parent_node;
 433
 434         /*
 435          * Get the currently attached parent object. Add a reference,
 436          * because the ref count will be decreased when the method object
 437          * is installed to the parent node.
 438          */
 439         parent_obj = acpi_ns_get_attached_object(parent_node);
 440         if (parent_obj) {
 441                 acpi_ut_add_reference(parent_obj);
 442         }
 443
 444         /* Install the method (module-level code) in the parent node */
 445
 446         status =
 447             acpi_ns_attach_object(parent_node, method_obj, ACPI_TYPE_METHOD);
 448         if (ACPI_FAILURE(status)) {
 449                 goto exit;
 450         }
 451
 452         /* Execute the parent node as a control method */
 453
 454         status = acpi_ns_evaluate(info);
 455
 456         ACPI_DEBUG_PRINT((ACPI_DB_INIT_NAMES,
 457                           "Executed module-level code at %p\n",
 458                           method_obj->method.aml_start));
 459
 460         /* Delete a possible implicit return value (in slack mode) */
 461
 462         if (info->return_object) {
 463                 acpi_ut_remove_reference(info->return_object);
 464         }
 465
 466         /* Detach the temporary method object */
 467
 468         acpi_ns_detach_object(parent_node);
 469
 470         /* Restore the original parent object */
 471
 472         if (parent_obj) {
 473                 status = acpi_ns_attach_object(parent_node, parent_obj, type);
 474         } else {
 475                 parent_node->type = (u8)type;
 476         }
 477
 478 exit:
 479         if (parent_obj) {
 480                 acpi_ut_remove_reference(parent_obj);
 481         }
 482         return_VOID;
 483 }