1 /*******************************************************************************
2  *
3  * Module Name: nsalloc - Namespace allocation and deletion utilities
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2011, 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 "accommon.h"
46 #include "acnamesp.h"
47 
48 #define _COMPONENT          ACPI_NAMESPACE
49 ACPI_MODULE_NAME("nsalloc")
50 
51 /*******************************************************************************
52  *
53  * FUNCTION:    acpi_ns_create_node
54  *
55  * PARAMETERS:  Name            - Name of the new node (4 char ACPI name)
56  *
57  * RETURN:      New namespace node (Null on failure)
58  *
59  * DESCRIPTION: Create a namespace node
60  *
61  ******************************************************************************/
acpi_ns_create_node(u32 name)62 struct acpi_namespace_node *acpi_ns_create_node(u32 name)
63 {
64 	struct acpi_namespace_node *node;
65 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
66 	u32 temp;
67 #endif
68 
69 	ACPI_FUNCTION_TRACE(ns_create_node);
70 
71 	node = acpi_os_acquire_object(acpi_gbl_namespace_cache);
72 	if (!node) {
73 		return_PTR(NULL);
74 	}
75 
76 	ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_allocated++);
77 
78 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
79 	temp = 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. All node deletions must come through
100  *              here. Detaches any attached objects, including any attached
101  *              data. If a handler is associated with attached data, it is
102  *              invoked before the node is deleted.
103  *
104  ******************************************************************************/
105 
acpi_ns_delete_node(struct acpi_namespace_node * node)106 void acpi_ns_delete_node(struct acpi_namespace_node *node)
107 {
108 	union acpi_operand_object *obj_desc;
109 
110 	ACPI_FUNCTION_NAME(ns_delete_node);
111 
112 	/* Detach an object if there is one */
113 
114 	acpi_ns_detach_object(node);
115 
116 	/*
117 	 * Delete an attached data object if present (an object that was created
118 	 * and attached via acpi_attach_data). Note: After any normal object is
119 	 * detached above, the only possible remaining object is a data object.
120 	 */
121 	obj_desc = node->object;
122 	if (obj_desc && (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA)) {
123 
124 		/* Invoke the attached data deletion handler if present */
125 
126 		if (obj_desc->data.handler) {
127 			obj_desc->data.handler(node, obj_desc->data.pointer);
128 		}
129 
130 		acpi_ut_remove_reference(obj_desc);
131 	}
132 
133 	/* Now we can delete the node */
134 
135 	(void)acpi_os_release_object(acpi_gbl_namespace_cache, node);
136 
137 	ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
138 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Node %p, Remaining %X\n",
139 			  node, acpi_gbl_current_node_count));
140 }
141 
142 /*******************************************************************************
143  *
144  * FUNCTION:    acpi_ns_remove_node
145  *
146  * PARAMETERS:  Node            - Node to be removed/deleted
147  *
148  * RETURN:      None
149  *
150  * DESCRIPTION: Remove (unlink) and delete a namespace node
151  *
152  ******************************************************************************/
153 
acpi_ns_remove_node(struct acpi_namespace_node * node)154 void acpi_ns_remove_node(struct acpi_namespace_node *node)
155 {
156 	struct acpi_namespace_node *parent_node;
157 	struct acpi_namespace_node *prev_node;
158 	struct acpi_namespace_node *next_node;
159 
160 	ACPI_FUNCTION_TRACE_PTR(ns_remove_node, node);
161 
162 	parent_node = node->parent;
163 
164 	prev_node = NULL;
165 	next_node = parent_node->child;
166 
167 	/* Find the node that is the previous peer in the parent's child list */
168 
169 	while (next_node != node) {
170 		prev_node = next_node;
171 		next_node = next_node->peer;
172 	}
173 
174 	if (prev_node) {
175 
176 		/* Node is not first child, unlink it */
177 
178 		prev_node->peer = node->peer;
179 	} else {
180 		/*
181 		 * Node is first child (has no previous peer).
182 		 * Link peer list to parent
183 		 */
184 		parent_node->child = node->peer;
185 	}
186 
187 	/* Delete the node and any attached objects */
188 
189 	acpi_ns_delete_node(node);
190 	return_VOID;
191 }
192 
193 /*******************************************************************************
194  *
195  * FUNCTION:    acpi_ns_install_node
196  *
197  * PARAMETERS:  walk_state      - Current state of the walk
198  *              parent_node     - The parent of the new Node
199  *              Node            - The new Node to install
200  *              Type            - ACPI object type of the new Node
201  *
202  * RETURN:      None
203  *
204  * DESCRIPTION: Initialize a new namespace node and install it amongst
205  *              its peers.
206  *
207  *              Note: Current namespace lookup is linear search. This appears
208  *              to be sufficient as namespace searches consume only a small
209  *              fraction of the execution time of the ACPI subsystem.
210  *
211  ******************************************************************************/
212 
acpi_ns_install_node(struct acpi_walk_state * walk_state,struct acpi_namespace_node * parent_node,struct acpi_namespace_node * node,acpi_object_type type)213 void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namespace_node *parent_node,	/* Parent */
214 			  struct acpi_namespace_node *node,	/* New Child */
215 			  acpi_object_type type)
216 {
217 	acpi_owner_id owner_id = 0;
218 	struct acpi_namespace_node *child_node;
219 
220 	ACPI_FUNCTION_TRACE(ns_install_node);
221 
222 	if (walk_state) {
223 		/*
224 		 * Get the owner ID from the Walk state. The owner ID is used to
225 		 * track table deletion and deletion of objects created by methods.
226 		 */
227 		owner_id = walk_state->owner_id;
228 
229 		if ((walk_state->method_desc) &&
230 		    (parent_node != walk_state->method_node)) {
231 			/*
232 			 * A method is creating a new node that is not a child of the
233 			 * method (it is non-local). Mark the executing method as having
234 			 * modified the namespace. This is used for cleanup when the
235 			 * method exits.
236 			 */
237 			walk_state->method_desc->method.info_flags |=
238 			    ACPI_METHOD_MODIFIED_NAMESPACE;
239 		}
240 	}
241 
242 	/* Link the new entry into the parent and existing children */
243 
244 	node->peer = NULL;
245 	node->parent = parent_node;
246 	child_node = parent_node->child;
247 
248 	if (!child_node) {
249 		parent_node->child = node;
250 	} else {
251 		/* Add node to the end of the peer list */
252 
253 		while (child_node->peer) {
254 			child_node = child_node->peer;
255 		}
256 
257 		child_node->peer = node;
258 	}
259 
260 	/* Init the new entry */
261 
262 	node->owner_id = owner_id;
263 	node->type = (u8) type;
264 
265 	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
266 			  "%4.4s (%s) [Node %p Owner %X] added to %4.4s (%s) [Node %p]\n",
267 			  acpi_ut_get_node_name(node),
268 			  acpi_ut_get_type_name(node->type), node, owner_id,
269 			  acpi_ut_get_node_name(parent_node),
270 			  acpi_ut_get_type_name(parent_node->type),
271 			  parent_node));
272 
273 	return_VOID;
274 }
275 
276 /*******************************************************************************
277  *
278  * FUNCTION:    acpi_ns_delete_children
279  *
280  * PARAMETERS:  parent_node     - Delete this objects children
281  *
282  * RETURN:      None.
283  *
284  * DESCRIPTION: Delete all children of the parent object. In other words,
285  *              deletes a "scope".
286  *
287  ******************************************************************************/
288 
acpi_ns_delete_children(struct acpi_namespace_node * parent_node)289 void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
290 {
291 	struct acpi_namespace_node *next_node;
292 	struct acpi_namespace_node *node_to_delete;
293 
294 	ACPI_FUNCTION_TRACE_PTR(ns_delete_children, parent_node);
295 
296 	if (!parent_node) {
297 		return_VOID;
298 	}
299 
300 	/* Deallocate all children at this level */
301 
302 	next_node = parent_node->child;
303 	while (next_node) {
304 
305 		/* Grandchildren should have all been deleted already */
306 
307 		if (next_node->child) {
308 			ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
309 				    parent_node, next_node));
310 		}
311 
312 		/*
313 		 * Delete this child node and move on to the next child in the list.
314 		 * No need to unlink the node since we are deleting the entire branch.
315 		 */
316 		node_to_delete = next_node;
317 		next_node = next_node->peer;
318 		acpi_ns_delete_node(node_to_delete);
319 	};
320 
321 	/* Clear the parent's child pointer */
322 
323 	parent_node->child = NULL;
324 	return_VOID;
325 }
326 
327 /*******************************************************************************
328  *
329  * FUNCTION:    acpi_ns_delete_namespace_subtree
330  *
331  * PARAMETERS:  parent_node     - Root of the subtree to be deleted
332  *
333  * RETURN:      None.
334  *
335  * DESCRIPTION: Delete a subtree of the namespace.  This includes all objects
336  *              stored within the subtree.
337  *
338  ******************************************************************************/
339 
acpi_ns_delete_namespace_subtree(struct acpi_namespace_node * parent_node)340 void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
341 {
342 	struct acpi_namespace_node *child_node = NULL;
343 	u32 level = 1;
344 	acpi_status status;
345 
346 	ACPI_FUNCTION_TRACE(ns_delete_namespace_subtree);
347 
348 	if (!parent_node) {
349 		return_VOID;
350 	}
351 
352 	/* Lock namespace for possible update */
353 
354 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
355 	if (ACPI_FAILURE(status)) {
356 		return_VOID;
357 	}
358 
359 	/*
360 	 * Traverse the tree of objects until we bubble back up
361 	 * to where we started.
362 	 */
363 	while (level > 0) {
364 
365 		/* Get the next node in this scope (NULL if none) */
366 
367 		child_node = acpi_ns_get_next_node(parent_node, child_node);
368 		if (child_node) {
369 
370 			/* Found a child node - detach any attached object */
371 
372 			acpi_ns_detach_object(child_node);
373 
374 			/* Check if this node has any children */
375 
376 			if (child_node->child) {
377 				/*
378 				 * There is at least one child of this node,
379 				 * visit the node
380 				 */
381 				level++;
382 				parent_node = child_node;
383 				child_node = NULL;
384 			}
385 		} else {
386 			/*
387 			 * No more children of this parent node.
388 			 * Move up to the grandparent.
389 			 */
390 			level--;
391 
392 			/*
393 			 * Now delete all of the children of this parent
394 			 * all at the same time.
395 			 */
396 			acpi_ns_delete_children(parent_node);
397 
398 			/* New "last child" is this parent node */
399 
400 			child_node = parent_node;
401 
402 			/* Move up the tree to the grandparent */
403 
404 			parent_node = parent_node->parent;
405 		}
406 	}
407 
408 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
409 	return_VOID;
410 }
411 
412 /*******************************************************************************
413  *
414  * FUNCTION:    acpi_ns_delete_namespace_by_owner
415  *
416  * PARAMETERS:  owner_id    - All nodes with this owner will be deleted
417  *
418  * RETURN:      Status
419  *
420  * DESCRIPTION: Delete entries within the namespace that are owned by a
421  *              specific ID.  Used to delete entire ACPI tables.  All
422  *              reference counts are updated.
423  *
424  * MUTEX:       Locks namespace during deletion walk.
425  *
426  ******************************************************************************/
427 
acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)428 void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
429 {
430 	struct acpi_namespace_node *child_node;
431 	struct acpi_namespace_node *deletion_node;
432 	struct acpi_namespace_node *parent_node;
433 	u32 level;
434 	acpi_status status;
435 
436 	ACPI_FUNCTION_TRACE_U32(ns_delete_namespace_by_owner, owner_id);
437 
438 	if (owner_id == 0) {
439 		return_VOID;
440 	}
441 
442 	/* Lock namespace for possible update */
443 
444 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
445 	if (ACPI_FAILURE(status)) {
446 		return_VOID;
447 	}
448 
449 	deletion_node = NULL;
450 	parent_node = acpi_gbl_root_node;
451 	child_node = NULL;
452 	level = 1;
453 
454 	/*
455 	 * Traverse the tree of nodes until we bubble back up
456 	 * to where we started.
457 	 */
458 	while (level > 0) {
459 		/*
460 		 * Get the next child of this parent node. When child_node is NULL,
461 		 * the first child of the parent is returned
462 		 */
463 		child_node = acpi_ns_get_next_node(parent_node, child_node);
464 
465 		if (deletion_node) {
466 			acpi_ns_delete_children(deletion_node);
467 			acpi_ns_remove_node(deletion_node);
468 			deletion_node = NULL;
469 		}
470 
471 		if (child_node) {
472 			if (child_node->owner_id == owner_id) {
473 
474 				/* Found a matching child node - detach any attached object */
475 
476 				acpi_ns_detach_object(child_node);
477 			}
478 
479 			/* Check if this node has any children */
480 
481 			if (child_node->child) {
482 				/*
483 				 * There is at least one child of this node,
484 				 * visit the node
485 				 */
486 				level++;
487 				parent_node = child_node;
488 				child_node = NULL;
489 			} else if (child_node->owner_id == owner_id) {
490 				deletion_node = child_node;
491 			}
492 		} else {
493 			/*
494 			 * No more children of this parent node.
495 			 * Move up to the grandparent.
496 			 */
497 			level--;
498 			if (level != 0) {
499 				if (parent_node->owner_id == owner_id) {
500 					deletion_node = parent_node;
501 				}
502 			}
503 
504 			/* New "last child" is this parent node */
505 
506 			child_node = parent_node;
507 
508 			/* Move up the tree to the grandparent */
509 
510 			parent_node = parent_node->parent;
511 		}
512 	}
513 
514 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
515 	return_VOID;
516 }
517