Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus
[linux-2.6] / drivers / acpi / namespace / nsalloc.c
1 /*******************************************************************************
2  *
3  * Module Name: nsalloc - Namespace allocation and deletion utilities
4  *
5  ******************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2008, 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 <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 }