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 /*******************************************************************************
  18  *
  19  * FUNCTION:    acpi_ns_evaluate
  20  *
  21  * PARAMETERS:  info            - Evaluation info block, contains these fields
  22  *                                and more:
  23  *                  prefix_node     - Prefix or Method/Object Node to execute
  24  *                  relative_path   - Name of method to execute, If NULL, the
  25  *                                    Node is the object to execute
  26  *                  parameters      - List of parameters to pass to the method,
  27  *                                    terminated by NULL. Params itself may be
  28  *                                    NULL if no parameters are being passed.
  29  *                  parameter_type  - Type of Parameter list
  30  *                  return_object   - Where to put method's return value (if
  31  *                                    any). If NULL, no value is returned.
  32  *                  flags           - ACPI_IGNORE_RETURN_VALUE to delete return
  33  *
  34  * RETURN:      Status
  35  *
  36  * DESCRIPTION: Execute a control method or return the current value of an
  37  *              ACPI namespace object.
  38  *
  39  * MUTEX:       Locks interpreter
  40  *
  41  ******************************************************************************/
  42 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info)
  43 {
  44         acpi_status status;
  45
  46         ACPI_FUNCTION_TRACE(ns_evaluate);
  47
  48         if (!info) {
  49                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  50         }
  51
  52         if (!info->node) {
  53                 /*
  54                  * Get the actual namespace node for the target object if we
  55                  * need to. Handles these cases:
  56                  *
  57                  * 1) Null node, valid pathname from root (absolute path)
  58                  * 2) Node and valid pathname (path relative to Node)
  59                  * 3) Node, Null pathname
  60                  */
  61                 status =
  62                     acpi_ns_get_node(info->prefix_node, info->relative_pathname,
  63                                      ACPI_NS_NO_UPSEARCH, &info->node);
  64                 if (ACPI_FAILURE(status)) {
  65                         return_ACPI_STATUS(status);
  66                 }
  67         }
  68
  69         /*
  70          * For a method alias, we must grab the actual method node so that
  71          * proper scoping context will be established before execution.
  72          */
  73         if (acpi_ns_get_type(info->node) == ACPI_TYPE_LOCAL_METHOD_ALIAS) {
  74                 info->node =
  75                     ACPI_CAST_PTR(struct acpi_namespace_node,
  76                                   info->node->object);
  77         }
  78
  79         /* Complete the info block initialization */
  80
  81         info->return_object = NULL;
  82         info->node_flags = info->node->flags;
  83         info->obj_desc = acpi_ns_get_attached_object(info->node);
  84
  85         ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n",
  86                           info->relative_pathname, info->node,
  87                           acpi_ns_get_attached_object(info->node)));
  88
  89         /* Get info if we have a predefined name (_HID, etc.) */
  90
  91         info->predefined =
  92             acpi_ut_match_predefined_method(info->node->name.ascii);
  93
  94         /* Get the full pathname to the object, for use in warning messages */
  95
  96         info->full_pathname = acpi_ns_get_normalized_pathname(info->node, TRUE);
  97         if (!info->full_pathname) {
  98                 return_ACPI_STATUS(AE_NO_MEMORY);
  99         }
 100
 101         /* Optional object evaluation log */
 102
 103         ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
 104                               "%-26s:  %s (%s)\n", "   Enter evaluation",
 105                               &info->full_pathname[1],
 106                               acpi_ut_get_type_name(info->node->type)));
 107
 108         /* Count the number of arguments being passed in */
 109
 110         info->param_count = 0;
 111         if (info->parameters) {
 112                 while (info->parameters[info->param_count]) {
 113                         info->param_count++;
 114                 }
 115
 116                 /* Warn on impossible argument count */
 117
 118                 if (info->param_count > ACPI_METHOD_NUM_ARGS) {
 119                         ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
 120                                               ACPI_WARN_ALWAYS,
 121                                               "Excess arguments (%u) - using only %u",
 122                                               info->param_count,
 123                                               ACPI_METHOD_NUM_ARGS));
 124
 125                         info->param_count = ACPI_METHOD_NUM_ARGS;
 126                 }
 127         }
 128
 129         /*
 130          * For predefined names: Check that the declared argument count
 131          * matches the ACPI spec -- otherwise this is a BIOS error.
 132          */
 133         acpi_ns_check_acpi_compliance(info->full_pathname, info->node,
 134                                       info->predefined);
 135
 136         /*
 137          * For all names: Check that the incoming argument count for
 138          * this method/object matches the actual ASL/AML definition.
 139          */
 140         acpi_ns_check_argument_count(info->full_pathname, info->node,
 141                                      info->param_count, info->predefined);
 142
 143         /* For predefined names: Typecheck all incoming arguments */
 144
 145         acpi_ns_check_argument_types(info);
 146
 147         /*
 148          * Three major evaluation cases:
 149          *
 150          * 1) Object types that cannot be evaluated by definition
 151          * 2) The object is a control method -- execute it
 152          * 3) The object is not a method -- just return it's current value
 153          */
 154         switch (acpi_ns_get_type(info->node)) {
 155         case ACPI_TYPE_ANY:
 156         case ACPI_TYPE_DEVICE:
 157         case ACPI_TYPE_EVENT:
 158         case ACPI_TYPE_MUTEX:
 159         case ACPI_TYPE_REGION:
 160         case ACPI_TYPE_THERMAL:
 161         case ACPI_TYPE_LOCAL_SCOPE:
 162                 /*
 163                  * 1) Disallow evaluation of these object types. For these,
 164                  *    object evaluation is undefined.
 165                  */
 166                 ACPI_ERROR((AE_INFO,
 167                             "%s: This object type [%s] "
 168                             "never contains data and cannot be evaluated",
 169                             info->full_pathname,
 170                             acpi_ut_get_type_name(info->node->type)));
 171
 172                 status = AE_TYPE;
 173                 goto cleanup;
 174
 175         case ACPI_TYPE_METHOD:
 176                 /*
 177                  * 2) Object is a control method - execute it
 178                  */
 179
 180                 /* Verify that there is a method object associated with this node */
 181
 182                 if (!info->obj_desc) {
 183                         ACPI_ERROR((AE_INFO,
 184                                     "%s: Method has no attached sub-object",
 185                                     info->full_pathname));
 186                         status = AE_NULL_OBJECT;
 187                         goto cleanup;
 188                 }
 189
 190                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 191                                   "**** Execute method [%s] at AML address %p length %X\n",
 192                                   info->full_pathname,
 193                                   info->obj_desc->method.aml_start + 1,
 194                                   info->obj_desc->method.aml_length - 1));
 195
 196                 /*
 197                  * Any namespace deletion must acquire both the namespace and
 198                  * interpreter locks to ensure that no thread is using the portion of
 199                  * the namespace that is being deleted.
 200                  *
 201                  * Execute the method via the interpreter. The interpreter is locked
 202                  * here before calling into the AML parser
 203                  */
 204                 acpi_ex_enter_interpreter();
 205                 status = acpi_ps_execute_method(info);
 206                 acpi_ex_exit_interpreter();
 207                 break;
 208
 209         default:
 210                 /*
 211                  * 3) All other non-method objects -- get the current object value
 212                  */
 213
 214                 /*
 215                  * Some objects require additional resolution steps (e.g., the Node
 216                  * may be a field that must be read, etc.) -- we can't just grab
 217                  * the object out of the node.
 218                  *
 219                  * Use resolve_node_to_value() to get the associated value.
 220                  *
 221                  * NOTE: we can get away with passing in NULL for a walk state because
 222                  * the Node is guaranteed to not be a reference to either a method
 223                  * local or a method argument (because this interface is never called
 224                  * from a running method.)
 225                  *
 226                  * Even though we do not directly invoke the interpreter for object
 227                  * resolution, we must lock it because we could access an op_region.
 228                  * The op_region access code assumes that the interpreter is locked.
 229                  */
 230                 acpi_ex_enter_interpreter();
 231
 232                 /* TBD: resolve_node_to_value has a strange interface, fix */
 233
 234                 info->return_object =
 235                     ACPI_CAST_PTR(union acpi_operand_object, info->node);
 236
 237                 status =
 238                     acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
 239                                                   (struct acpi_namespace_node,
 240                                                    &info->return_object), NULL);
 241                 acpi_ex_exit_interpreter();
 242
 243                 if (ACPI_FAILURE(status)) {
 244                         info->return_object = NULL;
 245                         goto cleanup;
 246                 }
 247
 248                 ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Returned object %p [%s]\n",
 249                                   info->return_object,
 250                                   acpi_ut_get_object_type_name(info->
 251                                                                return_object)));
 252
 253                 status = AE_CTRL_RETURN_VALUE;  /* Always has a "return value" */
 254                 break;
 255         }
 256
 257         /*
 258          * For predefined names, check the return value against the ACPI
 259          * specification. Some incorrect return value types are repaired.
 260          */
 261         (void)acpi_ns_check_return_value(info->node, info, info->param_count,
 262                                          status, &info->return_object);
 263
 264         /* Check if there is a return value that must be dealt with */
 265
 266         if (status == AE_CTRL_RETURN_VALUE) {
 267
 268                 /* If caller does not want the return value, delete it */
 269
 270                 if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
 271                         acpi_ut_remove_reference(info->return_object);
 272                         info->return_object = NULL;
 273                 }
 274
 275                 /* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
 276
 277                 status = AE_OK;
 278         } else if (ACPI_FAILURE(status)) {
 279
 280                 /* If return_object exists, delete it */
 281
 282                 if (info->return_object) {
 283                         acpi_ut_remove_reference(info->return_object);
 284                         info->return_object = NULL;
 285                 }
 286         }
 287
 288         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
 289                           "*** Completed evaluation of object %s ***\n",
 290                           info->relative_pathname));
 291
 292 cleanup:
 293         /* Optional object evaluation log */
 294
 295         ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
 296                               "%-26s:  %s\n", "   Exit evaluation",
 297                               &info->full_pathname[1]));
 298
 299         /*
 300          * Namespace was unlocked by the handling acpi_ns* function, so we
 301          * just free the pathname and return
 302          */
 303         ACPI_FREE(info->full_pathname);
 304         info->full_pathname = NULL;
 305         return_ACPI_STATUS(status);
 306 }