drivers/acpi/acpica/nsobject.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /*******************************************************************************
   3  *
   4  * Module Name: nsobject - Utilities for objects attached to namespace
   5  *                         table entries
   6  *
   7  ******************************************************************************/
   8
   9 #include <acpi/acpi.h>
  10 #include "accommon.h"
  11 #include "acnamesp.h"
  12
  13 #define _COMPONENT          ACPI_NAMESPACE
  14 ACPI_MODULE_NAME("nsobject")
  15
  16 /*******************************************************************************
  17  *
  18  * FUNCTION:    acpi_ns_attach_object
  19  *
  20  * PARAMETERS:  node                - Parent Node
  21  *              object              - Object to be attached
  22  *              type                - Type of object, or ACPI_TYPE_ANY if not
  23  *                                    known
  24  *
  25  * RETURN:      Status
  26  *
  27  * DESCRIPTION: Record the given object as the value associated with the
  28  *              name whose acpi_handle is passed. If Object is NULL
  29  *              and Type is ACPI_TYPE_ANY, set the name as having no value.
  30  *              Note: Future may require that the Node->Flags field be passed
  31  *              as a parameter.
  32  *
  33  * MUTEX:       Assumes namespace is locked
  34  *
  35  ******************************************************************************/
  36 acpi_status
  37 acpi_ns_attach_object(struct acpi_namespace_node *node,
  38                       union acpi_operand_object *object, acpi_object_type type)
  39 {
  40         union acpi_operand_object *obj_desc;
  41         union acpi_operand_object *last_obj_desc;
  42         acpi_object_type object_type = ACPI_TYPE_ANY;
  43
  44         ACPI_FUNCTION_TRACE(ns_attach_object);
  45
  46         /*
  47          * Parameter validation
  48          */
  49         if (!node) {
  50
  51                 /* Invalid handle */
  52
  53                 ACPI_ERROR((AE_INFO, "Null NamedObj handle"));
  54                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  55         }
  56
  57         if (!object && (ACPI_TYPE_ANY != type)) {
  58
  59                 /* Null object */
  60
  61                 ACPI_ERROR((AE_INFO,
  62                             "Null object, but type not ACPI_TYPE_ANY"));
  63                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  64         }
  65
  66         if (ACPI_GET_DESCRIPTOR_TYPE(node) != ACPI_DESC_TYPE_NAMED) {
  67
  68                 /* Not a name handle */
  69
  70                 ACPI_ERROR((AE_INFO, "Invalid handle %p [%s]",
  71                             node, acpi_ut_get_descriptor_name(node)));
  72                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  73         }
  74
  75         /* Check if this object is already attached */
  76
  77         if (node->object == object) {
  78                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  79                                   "Obj %p already installed in NameObj %p\n",
  80                                   object, node));
  81
  82                 return_ACPI_STATUS(AE_OK);
  83         }
  84
  85         /* If null object, we will just install it */
  86
  87         if (!object) {
  88                 obj_desc = NULL;
  89                 object_type = ACPI_TYPE_ANY;
  90         }
  91
  92         /*
  93          * If the source object is a namespace Node with an attached object,
  94          * we will use that (attached) object
  95          */
  96         else if ((ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) &&
  97                  ((struct acpi_namespace_node *)object)->object) {
  98                 /*
  99                  * Value passed is a name handle and that name has a
 100                  * non-null value. Use that name's value and type.
 101                  */
 102                 obj_desc = ((struct acpi_namespace_node *)object)->object;
 103                 object_type = ((struct acpi_namespace_node *)object)->type;
 104         }
 105
 106         /*
 107          * Otherwise, we will use the parameter object, but we must type
 108          * it first
 109          */
 110         else {
 111                 obj_desc = (union acpi_operand_object *)object;
 112
 113                 /* Use the given type */
 114
 115                 object_type = type;
 116         }
 117
 118         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Installing %p into Node %p [%4.4s]\n",
 119                           obj_desc, node, acpi_ut_get_node_name(node)));
 120
 121         /* Detach an existing attached object if present */
 122
 123         if (node->object) {
 124                 acpi_ns_detach_object(node);
 125         }
 126
 127         if (obj_desc) {
 128                 /*
 129                  * Must increment the new value's reference count
 130                  * (if it is an internal object)
 131                  */
 132                 acpi_ut_add_reference(obj_desc);
 133
 134                 /*
 135                  * Handle objects with multiple descriptors - walk
 136                  * to the end of the descriptor list
 137                  */
 138                 last_obj_desc = obj_desc;
 139                 while (last_obj_desc->common.next_object) {
 140                         last_obj_desc = last_obj_desc->common.next_object;
 141                 }
 142
 143                 /* Install the object at the front of the object list */
 144
 145                 last_obj_desc->common.next_object = node->object;
 146         }
 147
 148         node->type = (u8) object_type;
 149         node->object = obj_desc;
 150
 151         return_ACPI_STATUS(AE_OK);
 152 }
 153
 154 /*******************************************************************************
 155  *
 156  * FUNCTION:    acpi_ns_detach_object
 157  *
 158  * PARAMETERS:  node           - A Namespace node whose object will be detached
 159  *
 160  * RETURN:      None.
 161  *
 162  * DESCRIPTION: Detach/delete an object associated with a namespace node.
 163  *              if the object is an allocated object, it is freed.
 164  *              Otherwise, the field is simply cleared.
 165  *
 166  ******************************************************************************/
 167
 168 void acpi_ns_detach_object(struct acpi_namespace_node *node)
 169 {
 170         union acpi_operand_object *obj_desc;
 171
 172         ACPI_FUNCTION_TRACE(ns_detach_object);
 173
 174         obj_desc = node->object;
 175
 176         if (!obj_desc || (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA)) {
 177                 return_VOID;
 178         }
 179
 180         if (node->flags & ANOBJ_ALLOCATED_BUFFER) {
 181
 182                 /* Free the dynamic aml buffer */
 183
 184                 if (obj_desc->common.type == ACPI_TYPE_METHOD) {
 185                         ACPI_FREE(obj_desc->method.aml_start);
 186                 }
 187         }
 188
 189         /* Clear the Node entry in all cases */
 190
 191         node->object = NULL;
 192         if (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) == ACPI_DESC_TYPE_OPERAND) {
 193
 194                 /* Unlink object from front of possible object list */
 195
 196                 node->object = obj_desc->common.next_object;
 197
 198                 /* Handle possible 2-descriptor object */
 199
 200                 if (node->object &&
 201                     (node->object->common.type != ACPI_TYPE_LOCAL_DATA)) {
 202                         node->object = node->object->common.next_object;
 203                 }
 204
 205                 /*
 206                  * Detach the object from any data objects (which are still held by
 207                  * the namespace node)
 208                  */
 209                 if (obj_desc->common.next_object &&
 210                     ((obj_desc->common.next_object)->common.type ==
 211                      ACPI_TYPE_LOCAL_DATA)) {
 212                         obj_desc->common.next_object = NULL;
 213                 }
 214         }
 215
 216         /* Reset the node type to untyped */
 217
 218         node->type = ACPI_TYPE_ANY;
 219
 220         ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Node %p [%4.4s] Object %p\n",
 221                           node, acpi_ut_get_node_name(node), obj_desc));
 222
 223         /* Remove one reference on the object (and all subobjects) */
 224
 225         acpi_ut_remove_reference(obj_desc);
 226         return_VOID;
 227 }
 228
 229 /*******************************************************************************
 230  *
 231  * FUNCTION:    acpi_ns_get_attached_object
 232  *
 233  * PARAMETERS:  node             - Namespace node
 234  *
 235  * RETURN:      Current value of the object field from the Node whose
 236  *              handle is passed
 237  *
 238  * DESCRIPTION: Obtain the object attached to a namespace node.
 239  *
 240  ******************************************************************************/
 241
 242 union acpi_operand_object *acpi_ns_get_attached_object(struct
 243                                                        acpi_namespace_node
 244                                                        *node)
 245 {
 246         ACPI_FUNCTION_TRACE_PTR(ns_get_attached_object, node);
 247
 248         if (!node) {
 249                 ACPI_WARNING((AE_INFO, "Null Node ptr"));
 250                 return_PTR(NULL);
 251         }
 252
 253         if (!node->object ||
 254             ((ACPI_GET_DESCRIPTOR_TYPE(node->object) != ACPI_DESC_TYPE_OPERAND)
 255              && (ACPI_GET_DESCRIPTOR_TYPE(node->object) !=
 256                  ACPI_DESC_TYPE_NAMED))
 257             || ((node->object)->common.type == ACPI_TYPE_LOCAL_DATA)) {
 258                 return_PTR(NULL);
 259         }
 260
 261         return_PTR(node->object);
 262 }
 263
 264 /*******************************************************************************
 265  *
 266  * FUNCTION:    acpi_ns_get_secondary_object
 267  *
 268  * PARAMETERS:  node             - Namespace node
 269  *
 270  * RETURN:      Current value of the object field from the Node whose
 271  *              handle is passed.
 272  *
 273  * DESCRIPTION: Obtain a secondary object associated with a namespace node.
 274  *
 275  ******************************************************************************/
 276
 277 union acpi_operand_object *acpi_ns_get_secondary_object(union
 278                                                         acpi_operand_object
 279                                                         *obj_desc)
 280 {
 281         ACPI_FUNCTION_TRACE_PTR(ns_get_secondary_object, obj_desc);
 282
 283         if ((!obj_desc) ||
 284             (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) ||
 285             (!obj_desc->common.next_object) ||
 286             ((obj_desc->common.next_object)->common.type ==
 287              ACPI_TYPE_LOCAL_DATA)) {
 288                 return_PTR(NULL);
 289         }
 290
 291         return_PTR(obj_desc->common.next_object);
 292 }
 293
 294 /*******************************************************************************
 295  *
 296  * FUNCTION:    acpi_ns_attach_data
 297  *
 298  * PARAMETERS:  node            - Namespace node
 299  *              handler         - Handler to be associated with the data
 300  *              data            - Data to be attached
 301  *
 302  * RETURN:      Status
 303  *
 304  * DESCRIPTION: Low-level attach data. Create and attach a Data object.
 305  *
 306  ******************************************************************************/
 307
 308 acpi_status
 309 acpi_ns_attach_data(struct acpi_namespace_node *node,
 310                     acpi_object_handler handler, void *data)
 311 {
 312         union acpi_operand_object *prev_obj_desc;
 313         union acpi_operand_object *obj_desc;
 314         union acpi_operand_object *data_desc;
 315
 316         /* We only allow one attachment per handler */
 317
 318         prev_obj_desc = NULL;
 319         obj_desc = node->object;
 320         while (obj_desc) {
 321                 if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
 322                     (obj_desc->data.handler == handler)) {
 323                         return (AE_ALREADY_EXISTS);
 324                 }
 325
 326                 prev_obj_desc = obj_desc;
 327                 obj_desc = obj_desc->common.next_object;
 328         }
 329
 330         /* Create an internal object for the data */
 331
 332         data_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_DATA);
 333         if (!data_desc) {
 334                 return (AE_NO_MEMORY);
 335         }
 336
 337         data_desc->data.handler = handler;
 338         data_desc->data.pointer = data;
 339
 340         /* Install the data object */
 341
 342         if (prev_obj_desc) {
 343                 prev_obj_desc->common.next_object = data_desc;
 344         } else {
 345                 node->object = data_desc;
 346         }
 347
 348         return (AE_OK);
 349 }
 350
 351 /*******************************************************************************
 352  *
 353  * FUNCTION:    acpi_ns_detach_data
 354  *
 355  * PARAMETERS:  node            - Namespace node
 356  *              handler         - Handler associated with the data
 357  *
 358  * RETURN:      Status
 359  *
 360  * DESCRIPTION: Low-level detach data. Delete the data node, but the caller
 361  *              is responsible for the actual data.
 362  *
 363  ******************************************************************************/
 364
 365 acpi_status
 366 acpi_ns_detach_data(struct acpi_namespace_node *node,
 367                     acpi_object_handler handler)
 368 {
 369         union acpi_operand_object *obj_desc;
 370         union acpi_operand_object *prev_obj_desc;
 371
 372         prev_obj_desc = NULL;
 373         obj_desc = node->object;
 374         while (obj_desc) {
 375                 if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
 376                     (obj_desc->data.handler == handler)) {
 377                         if (prev_obj_desc) {
 378                                 prev_obj_desc->common.next_object =
 379                                     obj_desc->common.next_object;
 380                         } else {
 381                                 node->object = obj_desc->common.next_object;
 382                         }
 383
 384                         acpi_ut_remove_reference(obj_desc);
 385                         return (AE_OK);
 386                 }
 387
 388                 prev_obj_desc = obj_desc;
 389                 obj_desc = obj_desc->common.next_object;
 390         }
 391
 392         return (AE_NOT_FOUND);
 393 }
 394
 395 /*******************************************************************************
 396  *
 397  * FUNCTION:    acpi_ns_get_attached_data
 398  *
 399  * PARAMETERS:  node            - Namespace node
 400  *              handler         - Handler associated with the data
 401  *              data            - Where the data is returned
 402  *
 403  * RETURN:      Status
 404  *
 405  * DESCRIPTION: Low level interface to obtain data previously associated with
 406  *              a namespace node.
 407  *
 408  ******************************************************************************/
 409
 410 acpi_status
 411 acpi_ns_get_attached_data(struct acpi_namespace_node *node,
 412                           acpi_object_handler handler, void **data)
 413 {
 414         union acpi_operand_object *obj_desc;
 415
 416         obj_desc = node->object;
 417         while (obj_desc) {
 418                 if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
 419                     (obj_desc->data.handler == handler)) {
 420                         *data = obj_desc->data.pointer;
 421                         return (AE_OK);
 422                 }
 423
 424                 obj_desc = obj_desc->common.next_object;
 425         }
 426
 427         return (AE_NOT_FOUND);
 428 }