err.no Git - linux-2.6/blob - drivers/acpi/namespace/nsalloc.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: nsalloc - Namespace allocation and deletion utilities
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2007, R. Byron Moore
   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 <acpi/acnamesp.h>
  46
  47 #define _COMPONENT          ACPI_NAMESPACE
  48 ACPI_MODULE_NAME("nsalloc")
  49
  50 /*******************************************************************************
  51  *
  52  * FUNCTION:    acpi_ns_create_node
  53  *
  54  * PARAMETERS:  Name            - Name of the new node (4 char ACPI name)
  55  *
  56  * RETURN:      New namespace node (Null on failure)
  57  *
  58  * DESCRIPTION: Create a namespace node
  59  *
  60  ******************************************************************************/
  61 struct acpi_namespace_node *acpi_ns_create_node(u32 name)
  62 {
  63         struct acpi_namespace_node *node;
  64 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
  65         u32 temp;
  66 #endif
  67
  68         ACPI_FUNCTION_TRACE(ns_create_node);
  69
  70         node = acpi_os_acquire_object(acpi_gbl_namespace_cache);
  71         if (!node) {
  72                 return_PTR(NULL);
  73         }
  74
  75         ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_allocated++);
  76
  77 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
  78         temp =
  79             acpi_gbl_ns_node_list->total_allocated -
  80             acpi_gbl_ns_node_list->total_freed;
  81         if (temp > acpi_gbl_ns_node_list->max_occupied) {
  82                 acpi_gbl_ns_node_list->max_occupied = temp;
  83         }
  84 #endif
  85
  86         node->name.integer = name;
  87         ACPI_SET_DESCRIPTOR_TYPE(node, ACPI_DESC_TYPE_NAMED);
  88         return_PTR(node);
  89 }
  90
  91 /*******************************************************************************
  92  *
  93  * FUNCTION:    acpi_ns_delete_node
  94  *
  95  * PARAMETERS:  Node            - Node to be deleted
  96  *
  97  * RETURN:      None
  98  *
  99  * DESCRIPTION: Delete a namespace node
 100  *
 101  ******************************************************************************/
 102
 103 void acpi_ns_delete_node(struct acpi_namespace_node *node)
 104 {
 105         struct acpi_namespace_node *parent_node;
 106         struct acpi_namespace_node *prev_node;
 107         struct acpi_namespace_node *next_node;
 108
 109         ACPI_FUNCTION_TRACE_PTR(ns_delete_node, node);
 110
 111         parent_node = acpi_ns_get_parent_node(node);
 112
 113         prev_node = NULL;
 114         next_node = parent_node->child;
 115
 116         /* Find the node that is the previous peer in the parent's child list */
 117
 118         while (next_node != node) {
 119                 prev_node = next_node;
 120                 next_node = prev_node->peer;
 121         }
 122
 123         if (prev_node) {
 124
 125                 /* Node is not first child, unlink it */
 126
 127                 prev_node->peer = next_node->peer;
 128                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
 129                         prev_node->flags |= ANOBJ_END_OF_PEER_LIST;
 130                 }
 131         } else {
 132                 /* Node is first child (has no previous peer) */
 133
 134                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
 135
 136                         /* No peers at all */
 137
 138                         parent_node->child = NULL;
 139                 } else {        /* Link peer list to parent */
 140
 141                         parent_node->child = next_node->peer;
 142                 }
 143         }
 144
 145         ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
 146
 147         /*
 148          * Detach an object if there is one, then delete the node
 149          */
 150         acpi_ns_detach_object(node);
 151         (void)acpi_os_release_object(acpi_gbl_namespace_cache, node);
 152         return_VOID;
 153 }
 154
 155 /*******************************************************************************
 156  *
 157  * FUNCTION:    acpi_ns_install_node
 158  *
 159  * PARAMETERS:  walk_state      - Current state of the walk
 160  *              parent_node     - The parent of the new Node
 161  *              Node            - The new Node to install
 162  *              Type            - ACPI object type of the new Node
 163  *
 164  * RETURN:      None
 165  *
 166  * DESCRIPTION: Initialize a new namespace node and install it amongst
 167  *              its peers.
 168  *
 169  *              Note: Current namespace lookup is linear search. This appears
 170  *              to be sufficient as namespace searches consume only a small
 171  *              fraction of the execution time of the ACPI subsystem.
 172  *
 173  ******************************************************************************/
 174
 175 void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namespace_node *parent_node,  /* Parent */
 176                           struct acpi_namespace_node *node,     /* New Child */
 177                           acpi_object_type type)
 178 {
 179         acpi_owner_id owner_id = 0;
 180         struct acpi_namespace_node *child_node;
 181
 182         ACPI_FUNCTION_TRACE(ns_install_node);
 183
 184         /*
 185          * Get the owner ID from the Walk state
 186          * The owner ID is used to track table deletion and
 187          * deletion of objects created by methods
 188          */
 189         if (walk_state) {
 190                 owner_id = walk_state->owner_id;
 191         }
 192
 193         /* Link the new entry into the parent and existing children */
 194
 195         child_node = parent_node->child;
 196         if (!child_node) {
 197                 parent_node->child = node;
 198                 node->flags |= ANOBJ_END_OF_PEER_LIST;
 199                 node->peer = parent_node;
 200         } else {
 201                 while (!(child_node->flags & ANOBJ_END_OF_PEER_LIST)) {
 202                         child_node = child_node->peer;
 203                 }
 204
 205                 child_node->peer = node;
 206
 207                 /* Clear end-of-list flag */
 208
 209                 child_node->flags &= ~ANOBJ_END_OF_PEER_LIST;
 210                 node->flags |= ANOBJ_END_OF_PEER_LIST;
 211                 node->peer = parent_node;
 212         }
 213
 214         /* Init the new entry */
 215
 216         node->owner_id = owner_id;
 217         node->type = (u8) type;
 218
 219         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
 220                           "%4.4s (%s) [Node %p Owner %X] added to %4.4s (%s) [Node %p]\n",
 221                           acpi_ut_get_node_name(node),
 222                           acpi_ut_get_type_name(node->type), node, owner_id,
 223                           acpi_ut_get_node_name(parent_node),
 224                           acpi_ut_get_type_name(parent_node->type),
 225                           parent_node));
 226
 227         return_VOID;
 228 }
 229
 230 /*******************************************************************************
 231  *
 232  * FUNCTION:    acpi_ns_delete_children
 233  *
 234  * PARAMETERS:  parent_node     - Delete this objects children
 235  *
 236  * RETURN:      None.
 237  *
 238  * DESCRIPTION: Delete all children of the parent object. In other words,
 239  *              deletes a "scope".
 240  *
 241  ******************************************************************************/
 242
 243 void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
 244 {
 245         struct acpi_namespace_node *child_node;
 246         struct acpi_namespace_node *next_node;
 247         u8 flags;
 248
 249         ACPI_FUNCTION_TRACE_PTR(ns_delete_children, parent_node);
 250
 251         if (!parent_node) {
 252                 return_VOID;
 253         }
 254
 255         /* If no children, all done! */
 256
 257         child_node = parent_node->child;
 258         if (!child_node) {
 259                 return_VOID;
 260         }
 261
 262         /*
 263          * Deallocate all children at this level
 264          */
 265         do {
 266
 267                 /* Get the things we need */
 268
 269                 next_node = child_node->peer;
 270                 flags = child_node->flags;
 271
 272                 /* Grandchildren should have all been deleted already */
 273
 274                 if (child_node->child) {
 275                         ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
 276                                     parent_node, child_node));
 277                 }
 278
 279                 /* Now we can free this child object */
 280
 281                 ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
 282
 283                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 284                                   "Object %p, Remaining %X\n", child_node,
 285                                   acpi_gbl_current_node_count));
 286
 287                 /*
 288                  * Detach an object if there is one, then free the child node
 289                  */
 290                 acpi_ns_detach_object(child_node);
 291
 292                 /* Now we can delete the node */
 293
 294                 (void)acpi_os_release_object(acpi_gbl_namespace_cache,
 295                                              child_node);
 296
 297                 /* And move on to the next child in the list */
 298
 299                 child_node = next_node;
 300
 301         } while (!(flags & ANOBJ_END_OF_PEER_LIST));
 302
 303         /* Clear the parent's child pointer */
 304
 305         parent_node->child = NULL;
 306
 307         return_VOID;
 308 }
 309
 310 /*******************************************************************************
 311  *
 312  * FUNCTION:    acpi_ns_delete_namespace_subtree
 313  *
 314  * PARAMETERS:  parent_node     - Root of the subtree to be deleted
 315  *
 316  * RETURN:      None.
 317  *
 318  * DESCRIPTION: Delete a subtree of the namespace.  This includes all objects
 319  *              stored within the subtree.
 320  *
 321  ******************************************************************************/
 322
 323 void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
 324 {
 325         struct acpi_namespace_node *child_node = NULL;
 326         u32 level = 1;
 327
 328         ACPI_FUNCTION_TRACE(ns_delete_namespace_subtree);
 329
 330         if (!parent_node) {
 331                 return_VOID;
 332         }
 333
 334         /*
 335          * Traverse the tree of objects until we bubble back up
 336          * to where we started.
 337          */
 338         while (level > 0) {
 339
 340                 /* Get the next node in this scope (NULL if none) */
 341
 342                 child_node =
 343                     acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
 344                                           child_node);
 345                 if (child_node) {
 346
 347                         /* Found a child node - detach any attached object */
 348
 349                         acpi_ns_detach_object(child_node);
 350
 351                         /* Check if this node has any children */
 352
 353                         if (acpi_ns_get_next_node
 354                             (ACPI_TYPE_ANY, child_node, NULL)) {
 355                                 /*
 356                                  * There is at least one child of this node,
 357                                  * visit the node
 358                                  */
 359                                 level++;
 360                                 parent_node = child_node;
 361                                 child_node = NULL;
 362                         }
 363                 } else {
 364                         /*
 365                          * No more children of this parent node.
 366                          * Move up to the grandparent.
 367                          */
 368                         level--;
 369
 370                         /*
 371                          * Now delete all of the children of this parent
 372                          * all at the same time.
 373                          */
 374                         acpi_ns_delete_children(parent_node);
 375
 376                         /* New "last child" is this parent node */
 377
 378                         child_node = parent_node;
 379
 380                         /* Move up the tree to the grandparent */
 381
 382                         parent_node = acpi_ns_get_parent_node(parent_node);
 383                 }
 384         }
 385
 386         return_VOID;
 387 }
 388
 389 /*******************************************************************************
 390  *
 391  * FUNCTION:    acpi_ns_delete_namespace_by_owner
 392  *
 393  * PARAMETERS:  owner_id    - All nodes with this owner will be deleted
 394  *
 395  * RETURN:      Status
 396  *
 397  * DESCRIPTION: Delete entries within the namespace that are owned by a
 398  *              specific ID.  Used to delete entire ACPI tables.  All
 399  *              reference counts are updated.
 400  *
 401  * MUTEX:       Locks namespace during deletion walk.
 402  *
 403  ******************************************************************************/
 404
 405 void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
 406 {
 407         struct acpi_namespace_node *child_node;
 408         struct acpi_namespace_node *deletion_node;
 409         struct acpi_namespace_node *parent_node;
 410         u32 level;
 411         acpi_status status;
 412
 413         ACPI_FUNCTION_TRACE_U32(ns_delete_namespace_by_owner, owner_id);
 414
 415         if (owner_id == 0) {
 416                 return_VOID;
 417         }
 418
 419         /* Lock namespace for possible update */
 420
 421         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 422         if (ACPI_FAILURE(status)) {
 423                 return_VOID;
 424         }
 425
 426         deletion_node = NULL;
 427         parent_node = acpi_gbl_root_node;
 428         child_node = NULL;
 429         level = 1;
 430
 431         /*
 432          * Traverse the tree of nodes until we bubble back up
 433          * to where we started.
 434          */
 435         while (level > 0) {
 436                 /*
 437                  * Get the next child of this parent node. When child_node is NULL,
 438                  * the first child of the parent is returned
 439                  */
 440                 child_node =
 441                     acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
 442                                           child_node);
 443
 444                 if (deletion_node) {
 445                         acpi_ns_delete_children(deletion_node);
 446                         acpi_ns_delete_node(deletion_node);
 447                         deletion_node = NULL;
 448                 }
 449
 450                 if (child_node) {
 451                         if (child_node->owner_id == owner_id) {
 452
 453                                 /* Found a matching child node - detach any attached object */
 454
 455                                 acpi_ns_detach_object(child_node);
 456                         }
 457
 458                         /* Check if this node has any children */
 459
 460                         if (acpi_ns_get_next_node
 461                             (ACPI_TYPE_ANY, child_node, NULL)) {
 462                                 /*
 463                                  * There is at least one child of this node,
 464                                  * visit the node
 465                                  */
 466                                 level++;
 467                                 parent_node = child_node;
 468                                 child_node = NULL;
 469                         } else if (child_node->owner_id == owner_id) {
 470                                 deletion_node = child_node;
 471                         }
 472                 } else {
 473                         /*
 474                          * No more children of this parent node.
 475                          * Move up to the grandparent.
 476                          */
 477                         level--;
 478                         if (level != 0) {
 479                                 if (parent_node->owner_id == owner_id) {
 480                                         deletion_node = parent_node;
 481                                 }
 482                         }
 483
 484                         /* New "last child" is this parent node */
 485
 486                         child_node = parent_node;
 487
 488                         /* Move up the tree to the grandparent */
 489
 490                         parent_node = acpi_ns_get_parent_node(parent_node);
 491                 }
 492         }
 493
 494         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 495         return_VOID;
 496 }