8b921c96d6a5398e88a6986dff69c2ef66d1fb7d
[pandora-kernel.git] / drivers / acpi / namespace / nsalloc.c
1 /*******************************************************************************
2  *
3  * Module Name: nsalloc - Namespace allocation and deletion utilities
4  *
5  ******************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2006, 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
65         ACPI_FUNCTION_TRACE("ns_create_node");
66
67         node = acpi_os_acquire_object(acpi_gbl_namespace_cache);
68         if (!node) {
69                 return_PTR(NULL);
70         }
71
72         ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_allocated++);
73
74         node->name.integer = name;
75         ACPI_SET_DESCRIPTOR_TYPE(node, ACPI_DESC_TYPE_NAMED);
76         return_PTR(node);
77 }
78
79 /*******************************************************************************
80  *
81  * FUNCTION:    acpi_ns_delete_node
82  *
83  * PARAMETERS:  Node            - Node to be deleted
84  *
85  * RETURN:      None
86  *
87  * DESCRIPTION: Delete a namespace node
88  *
89  ******************************************************************************/
90
91 void acpi_ns_delete_node(struct acpi_namespace_node *node)
92 {
93         struct acpi_namespace_node *parent_node;
94         struct acpi_namespace_node *prev_node;
95         struct acpi_namespace_node *next_node;
96
97         ACPI_FUNCTION_TRACE_PTR("ns_delete_node", node);
98
99         parent_node = acpi_ns_get_parent_node(node);
100
101         prev_node = NULL;
102         next_node = parent_node->child;
103
104         /* Find the node that is the previous peer in the parent's child list */
105
106         while (next_node != node) {
107                 prev_node = next_node;
108                 next_node = prev_node->peer;
109         }
110
111         if (prev_node) {
112
113                 /* Node is not first child, unlink it */
114
115                 prev_node->peer = next_node->peer;
116                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
117                         prev_node->flags |= ANOBJ_END_OF_PEER_LIST;
118                 }
119         } else {
120                 /* Node is first child (has no previous peer) */
121
122                 if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
123
124                         /* No peers at all */
125
126                         parent_node->child = NULL;
127                 } else {        /* Link peer list to parent */
128
129                         parent_node->child = next_node->peer;
130                 }
131         }
132
133         ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
134
135         /*
136          * Detach an object if there is one, then delete the node
137          */
138         acpi_ns_detach_object(node);
139         (void)acpi_os_release_object(acpi_gbl_namespace_cache, node);
140         return_VOID;
141 }
142
143 /*******************************************************************************
144  *
145  * FUNCTION:    acpi_ns_install_node
146  *
147  * PARAMETERS:  walk_state      - Current state of the walk
148  *              parent_node     - The parent of the new Node
149  *              Node            - The new Node to install
150  *              Type            - ACPI object type of the new Node
151  *
152  * RETURN:      None
153  *
154  * DESCRIPTION: Initialize a new namespace node and install it amongst
155  *              its peers.
156  *
157  *              Note: Current namespace lookup is linear search. This appears
158  *              to be sufficient as namespace searches consume only a small
159  *              fraction of the execution time of the ACPI subsystem.
160  *
161  ******************************************************************************/
162
163 void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namespace_node *parent_node,  /* Parent */
164                           struct acpi_namespace_node *node,     /* New Child */
165                           acpi_object_type type)
166 {
167         acpi_owner_id owner_id = 0;
168         struct acpi_namespace_node *child_node;
169
170         ACPI_FUNCTION_TRACE("ns_install_node");
171
172         /*
173          * Get the owner ID from the Walk state
174          * The owner ID is used to track table deletion and
175          * deletion of objects created by methods
176          */
177         if (walk_state) {
178                 owner_id = walk_state->owner_id;
179         }
180
181         /* Link the new entry into the parent and existing children */
182
183         child_node = parent_node->child;
184         if (!child_node) {
185                 parent_node->child = node;
186                 node->flags |= ANOBJ_END_OF_PEER_LIST;
187                 node->peer = parent_node;
188         } else {
189                 while (!(child_node->flags & ANOBJ_END_OF_PEER_LIST)) {
190                         child_node = child_node->peer;
191                 }
192
193                 child_node->peer = node;
194
195                 /* Clear end-of-list flag */
196
197                 child_node->flags &= ~ANOBJ_END_OF_PEER_LIST;
198                 node->flags |= ANOBJ_END_OF_PEER_LIST;
199                 node->peer = parent_node;
200         }
201
202         /* Init the new entry */
203
204         node->owner_id = owner_id;
205         node->type = (u8) type;
206
207         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
208                           "%4.4s (%s) [Node %p Owner %X] added to %4.4s (%s) [Node %p]\n",
209                           acpi_ut_get_node_name(node),
210                           acpi_ut_get_type_name(node->type), node, owner_id,
211                           acpi_ut_get_node_name(parent_node),
212                           acpi_ut_get_type_name(parent_node->type),
213                           parent_node));
214 }
215
216 /*******************************************************************************
217  *
218  * FUNCTION:    acpi_ns_delete_children
219  *
220  * PARAMETERS:  parent_node     - Delete this objects children
221  *
222  * RETURN:      None.
223  *
224  * DESCRIPTION: Delete all children of the parent object. In other words,
225  *              deletes a "scope".
226  *
227  ******************************************************************************/
228
229 void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
230 {
231         struct acpi_namespace_node *child_node;
232         struct acpi_namespace_node *next_node;
233         u8 flags;
234
235         ACPI_FUNCTION_TRACE_PTR("ns_delete_children", parent_node);
236
237         if (!parent_node) {
238                 return_VOID;
239         }
240
241         /* If no children, all done! */
242
243         child_node = parent_node->child;
244         if (!child_node) {
245                 return_VOID;
246         }
247
248         /*
249          * Deallocate all children at this level
250          */
251         do {
252
253                 /* Get the things we need */
254
255                 next_node = child_node->peer;
256                 flags = child_node->flags;
257
258                 /* Grandchildren should have all been deleted already */
259
260                 if (child_node->child) {
261                         ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
262                                     parent_node, child_node));
263                 }
264
265                 /* Now we can free this child object */
266
267                 ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
268
269                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
270                                   "Object %p, Remaining %X\n", child_node,
271                                   acpi_gbl_current_node_count));
272
273                 /*
274                  * Detach an object if there is one, then free the child node
275                  */
276                 acpi_ns_detach_object(child_node);
277
278                 /* Now we can delete the node */
279
280                 (void)acpi_os_release_object(acpi_gbl_namespace_cache,
281                                              child_node);
282
283                 /* And move on to the next child in the list */
284
285                 child_node = next_node;
286
287         } while (!(flags & ANOBJ_END_OF_PEER_LIST));
288
289         /* Clear the parent's child pointer */
290
291         parent_node->child = NULL;
292
293         return_VOID;
294 }
295
296 /*******************************************************************************
297  *
298  * FUNCTION:    acpi_ns_delete_namespace_subtree
299  *
300  * PARAMETERS:  parent_node     - Root of the subtree to be deleted
301  *
302  * RETURN:      None.
303  *
304  * DESCRIPTION: Delete a subtree of the namespace.  This includes all objects
305  *              stored within the subtree.
306  *
307  ******************************************************************************/
308
309 void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
310 {
311         struct acpi_namespace_node *child_node = NULL;
312         u32 level = 1;
313
314         ACPI_FUNCTION_TRACE("ns_delete_namespace_subtree");
315
316         if (!parent_node) {
317                 return_VOID;
318         }
319
320         /*
321          * Traverse the tree of objects until we bubble back up
322          * to where we started.
323          */
324         while (level > 0) {
325
326                 /* Get the next node in this scope (NULL if none) */
327
328                 child_node =
329                     acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
330                                           child_node);
331                 if (child_node) {
332
333                         /* Found a child node - detach any attached object */
334
335                         acpi_ns_detach_object(child_node);
336
337                         /* Check if this node has any children */
338
339                         if (acpi_ns_get_next_node
340                             (ACPI_TYPE_ANY, child_node, NULL)) {
341                                 /*
342                                  * There is at least one child of this node,
343                                  * visit the node
344                                  */
345                                 level++;
346                                 parent_node = child_node;
347                                 child_node = NULL;
348                         }
349                 } else {
350                         /*
351                          * No more children of this parent node.
352                          * Move up to the grandparent.
353                          */
354                         level--;
355
356                         /*
357                          * Now delete all of the children of this parent
358                          * all at the same time.
359                          */
360                         acpi_ns_delete_children(parent_node);
361
362                         /* New "last child" is this parent node */
363
364                         child_node = parent_node;
365
366                         /* Move up the tree to the grandparent */
367
368                         parent_node = acpi_ns_get_parent_node(parent_node);
369                 }
370         }
371
372         return_VOID;
373 }
374
375 /*******************************************************************************
376  *
377  * FUNCTION:    acpi_ns_delete_namespace_by_owner
378  *
379  * PARAMETERS:  owner_id    - All nodes with this owner will be deleted
380  *
381  * RETURN:      Status
382  *
383  * DESCRIPTION: Delete entries within the namespace that are owned by a
384  *              specific ID.  Used to delete entire ACPI tables.  All
385  *              reference counts are updated.
386  *
387  ******************************************************************************/
388
389 void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
390 {
391         struct acpi_namespace_node *child_node;
392         struct acpi_namespace_node *deletion_node;
393         u32 level;
394         struct acpi_namespace_node *parent_node;
395
396         ACPI_FUNCTION_TRACE_U32("ns_delete_namespace_by_owner", owner_id);
397
398         if (owner_id == 0) {
399                 return_VOID;
400         }
401
402         deletion_node = NULL;
403         parent_node = acpi_gbl_root_node;
404         child_node = NULL;
405         level = 1;
406
407         /*
408          * Traverse the tree of nodes until we bubble back up
409          * to where we started.
410          */
411         while (level > 0) {
412                 /*
413                  * Get the next child of this parent node. When child_node is NULL,
414                  * the first child of the parent is returned
415                  */
416                 child_node =
417                     acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
418                                           child_node);
419
420                 if (deletion_node) {
421                         acpi_ns_delete_children(deletion_node);
422                         acpi_ns_delete_node(deletion_node);
423                         deletion_node = NULL;
424                 }
425
426                 if (child_node) {
427                         if (child_node->owner_id == owner_id) {
428
429                                 /* Found a matching child node - detach any attached object */
430
431                                 acpi_ns_detach_object(child_node);
432                         }
433
434                         /* Check if this node has any children */
435
436                         if (acpi_ns_get_next_node
437                             (ACPI_TYPE_ANY, child_node, NULL)) {
438                                 /*
439                                  * There is at least one child of this node,
440                                  * visit the node
441                                  */
442                                 level++;
443                                 parent_node = child_node;
444                                 child_node = NULL;
445                         } else if (child_node->owner_id == owner_id) {
446                                 deletion_node = child_node;
447                         }
448                 } else {
449                         /*
450                          * No more children of this parent node.
451                          * Move up to the grandparent.
452                          */
453                         level--;
454                         if (level != 0) {
455                                 if (parent_node->owner_id == owner_id) {
456                                         deletion_node = parent_node;
457                                 }
458                         }
459
460                         /* New "last child" is this parent node */
461
462                         child_node = parent_node;
463
464                         /* Move up the tree to the grandparent */
465
466                         parent_node = acpi_ns_get_parent_node(parent_node);
467                 }
468         }
469
470         return_VOID;
471 }