xref: /linux/drivers/acpi/acpica/nsalloc.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /*******************************************************************************
3  *
4  * Module Name: nsalloc - Namespace allocation and deletion utilities
5  *
6  ******************************************************************************/
7 
8 #include <acpi/acpi.h>
9 #include "accommon.h"
10 #include "acnamesp.h"
11 
12 #define _COMPONENT          ACPI_NAMESPACE
13 ACPI_MODULE_NAME("nsalloc")
14 
15 /*******************************************************************************
16  *
17  * FUNCTION:    acpi_ns_create_node
18  *
19  * PARAMETERS:  name            - Name of the new node (4 char ACPI name)
20  *
21  * RETURN:      New namespace node (Null on failure)
22  *
23  * DESCRIPTION: Create a namespace node
24  *
25  ******************************************************************************/
26 struct acpi_namespace_node *acpi_ns_create_node(u32 name)
27 {
28 	struct acpi_namespace_node *node;
29 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
30 	u32 temp;
31 #endif
32 
33 	ACPI_FUNCTION_TRACE(ns_create_node);
34 
35 	node = acpi_os_acquire_object(acpi_gbl_namespace_cache);
36 	if (!node) {
37 		return_PTR(NULL);
38 	}
39 
40 	ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_allocated++);
41 
42 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
43 	temp = acpi_gbl_ns_node_list->total_allocated -
44 	    acpi_gbl_ns_node_list->total_freed;
45 	if (temp > acpi_gbl_ns_node_list->max_occupied) {
46 		acpi_gbl_ns_node_list->max_occupied = temp;
47 	}
48 #endif
49 
50 	node->name.integer = name;
51 	ACPI_SET_DESCRIPTOR_TYPE(node, ACPI_DESC_TYPE_NAMED);
52 	return_PTR(node);
53 }
54 
55 /*******************************************************************************
56  *
57  * FUNCTION:    acpi_ns_delete_node
58  *
59  * PARAMETERS:  node            - Node to be deleted
60  *
61  * RETURN:      None
62  *
63  * DESCRIPTION: Delete a namespace node. All node deletions must come through
64  *              here. Detaches any attached objects, including any attached
65  *              data. If a handler is associated with attached data, it is
66  *              invoked before the node is deleted.
67  *
68  ******************************************************************************/
69 
70 void acpi_ns_delete_node(struct acpi_namespace_node *node)
71 {
72 	union acpi_operand_object *obj_desc;
73 	union acpi_operand_object *next_desc;
74 
75 	ACPI_FUNCTION_NAME(ns_delete_node);
76 
77 	/* Detach an object if there is one */
78 
79 	acpi_ns_detach_object(node);
80 
81 	/*
82 	 * Delete an attached data object list if present (objects that were
83 	 * attached via acpi_attach_data). Note: After any normal object is
84 	 * detached above, the only possible remaining object(s) are data
85 	 * objects, in a linked list.
86 	 */
87 	obj_desc = node->object;
88 	while (obj_desc && (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA)) {
89 
90 		/* Invoke the attached data deletion handler if present */
91 
92 		if (obj_desc->data.handler) {
93 			obj_desc->data.handler(node, obj_desc->data.pointer);
94 		}
95 
96 		next_desc = obj_desc->common.next_object;
97 		acpi_ut_remove_reference(obj_desc);
98 		obj_desc = next_desc;
99 	}
100 
101 	/* Special case for the statically allocated root node */
102 
103 	if (node == acpi_gbl_root_node) {
104 		return;
105 	}
106 
107 	/* Now we can delete the node */
108 
109 	(void)acpi_os_release_object(acpi_gbl_namespace_cache, node);
110 
111 	ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
112 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Node %p, Remaining %X\n",
113 			  node, acpi_gbl_current_node_count));
114 }
115 
116 /*******************************************************************************
117  *
118  * FUNCTION:    acpi_ns_remove_node
119  *
120  * PARAMETERS:  node            - Node to be removed/deleted
121  *
122  * RETURN:      None
123  *
124  * DESCRIPTION: Remove (unlink) and delete a namespace node
125  *
126  ******************************************************************************/
127 
128 void acpi_ns_remove_node(struct acpi_namespace_node *node)
129 {
130 	struct acpi_namespace_node *parent_node;
131 	struct acpi_namespace_node *prev_node;
132 	struct acpi_namespace_node *next_node;
133 
134 	ACPI_FUNCTION_TRACE_PTR(ns_remove_node, node);
135 
136 	parent_node = node->parent;
137 
138 	prev_node = NULL;
139 	next_node = parent_node->child;
140 
141 	/* Find the node that is the previous peer in the parent's child list */
142 
143 	while (next_node != node) {
144 		prev_node = next_node;
145 		next_node = next_node->peer;
146 	}
147 
148 	if (prev_node) {
149 
150 		/* Node is not first child, unlink it */
151 
152 		prev_node->peer = node->peer;
153 	} else {
154 		/*
155 		 * Node is first child (has no previous peer).
156 		 * Link peer list to parent
157 		 */
158 		parent_node->child = node->peer;
159 	}
160 
161 	/* Delete the node and any attached objects */
162 
163 	acpi_ns_delete_node(node);
164 	return_VOID;
165 }
166 
167 /*******************************************************************************
168  *
169  * FUNCTION:    acpi_ns_install_node
170  *
171  * PARAMETERS:  walk_state      - Current state of the walk
172  *              parent_node     - The parent of the new Node
173  *              node            - The new Node to install
174  *              type            - ACPI object type of the new Node
175  *
176  * RETURN:      None
177  *
178  * DESCRIPTION: Initialize a new namespace node and install it amongst
179  *              its peers.
180  *
181  *              Note: Current namespace lookup is linear search. This appears
182  *              to be sufficient as namespace searches consume only a small
183  *              fraction of the execution time of the ACPI subsystem.
184  *
185  ******************************************************************************/
186 
187 void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namespace_node *parent_node,	/* Parent */
188 			  struct acpi_namespace_node *node,	/* New Child */
189 			  acpi_object_type type)
190 {
191 	acpi_owner_id owner_id = 0;
192 	struct acpi_namespace_node *child_node;
193 
194 	ACPI_FUNCTION_TRACE(ns_install_node);
195 
196 	if (walk_state) {
197 		/*
198 		 * Get the owner ID from the Walk state. The owner ID is used to
199 		 * track table deletion and deletion of objects created by methods.
200 		 */
201 		owner_id = walk_state->owner_id;
202 
203 		if ((walk_state->method_desc) &&
204 		    (parent_node != walk_state->method_node)) {
205 			/*
206 			 * A method is creating a new node that is not a child of the
207 			 * method (it is non-local). Mark the executing method as having
208 			 * modified the namespace. This is used for cleanup when the
209 			 * method exits.
210 			 */
211 			walk_state->method_desc->method.info_flags |=
212 			    ACPI_METHOD_MODIFIED_NAMESPACE;
213 		}
214 	}
215 
216 	/* Link the new entry into the parent and existing children */
217 
218 	node->peer = NULL;
219 	node->parent = parent_node;
220 	child_node = parent_node->child;
221 
222 	if (!child_node) {
223 		parent_node->child = node;
224 	} else {
225 		/* Add node to the end of the peer list */
226 
227 		while (child_node->peer) {
228 			child_node = child_node->peer;
229 		}
230 
231 		child_node->peer = node;
232 	}
233 
234 	/* Init the new entry */
235 
236 	node->owner_id = owner_id;
237 	node->type = (u8) type;
238 
239 	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
240 			  "%4.4s (%s) [Node %p Owner %X] added to %4.4s (%s) [Node %p]\n",
241 			  acpi_ut_get_node_name(node),
242 			  acpi_ut_get_type_name(node->type), node, owner_id,
243 			  acpi_ut_get_node_name(parent_node),
244 			  acpi_ut_get_type_name(parent_node->type),
245 			  parent_node));
246 
247 	return_VOID;
248 }
249 
250 /*******************************************************************************
251  *
252  * FUNCTION:    acpi_ns_delete_children
253  *
254  * PARAMETERS:  parent_node     - Delete this objects children
255  *
256  * RETURN:      None.
257  *
258  * DESCRIPTION: Delete all children of the parent object. In other words,
259  *              deletes a "scope".
260  *
261  ******************************************************************************/
262 
263 void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
264 {
265 	struct acpi_namespace_node *next_node;
266 	struct acpi_namespace_node *node_to_delete;
267 
268 	ACPI_FUNCTION_TRACE_PTR(ns_delete_children, parent_node);
269 
270 	if (!parent_node) {
271 		return_VOID;
272 	}
273 
274 	/* Deallocate all children at this level */
275 
276 	next_node = parent_node->child;
277 	while (next_node) {
278 
279 		/* Grandchildren should have all been deleted already */
280 
281 		if (next_node->child) {
282 			ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
283 				    parent_node, next_node));
284 		}
285 
286 		/*
287 		 * Delete this child node and move on to the next child in the list.
288 		 * No need to unlink the node since we are deleting the entire branch.
289 		 */
290 		node_to_delete = next_node;
291 		next_node = next_node->peer;
292 		acpi_ns_delete_node(node_to_delete);
293 	};
294 
295 	/* Clear the parent's child pointer */
296 
297 	parent_node->child = NULL;
298 	return_VOID;
299 }
300 
301 /*******************************************************************************
302  *
303  * FUNCTION:    acpi_ns_delete_namespace_subtree
304  *
305  * PARAMETERS:  parent_node     - Root of the subtree to be deleted
306  *
307  * RETURN:      None.
308  *
309  * DESCRIPTION: Delete a subtree of the namespace. This includes all objects
310  *              stored within the subtree.
311  *
312  ******************************************************************************/
313 
314 void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
315 {
316 	struct acpi_namespace_node *child_node = NULL;
317 	u32 level = 1;
318 	acpi_status status;
319 
320 	ACPI_FUNCTION_TRACE(ns_delete_namespace_subtree);
321 
322 	if (!parent_node) {
323 		return_VOID;
324 	}
325 
326 	/* Lock namespace for possible update */
327 
328 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
329 	if (ACPI_FAILURE(status)) {
330 		return_VOID;
331 	}
332 
333 	/*
334 	 * Traverse the tree of objects until we bubble back up
335 	 * to where we started.
336 	 */
337 	while (level > 0) {
338 
339 		/* Get the next node in this scope (NULL if none) */
340 
341 		child_node = acpi_ns_get_next_node(parent_node, child_node);
342 		if (child_node) {
343 
344 			/* Found a child node - detach any attached object */
345 
346 			acpi_ns_detach_object(child_node);
347 
348 			/* Check if this node has any children */
349 
350 			if (child_node->child) {
351 				/*
352 				 * There is at least one child of this node,
353 				 * visit the node
354 				 */
355 				level++;
356 				parent_node = child_node;
357 				child_node = NULL;
358 			}
359 		} else {
360 			/*
361 			 * No more children of this parent node.
362 			 * Move up to the grandparent.
363 			 */
364 			level--;
365 
366 			/*
367 			 * Now delete all of the children of this parent
368 			 * all at the same time.
369 			 */
370 			acpi_ns_delete_children(parent_node);
371 
372 			/* New "last child" is this parent node */
373 
374 			child_node = parent_node;
375 
376 			/* Move up the tree to the grandparent */
377 
378 			parent_node = parent_node->parent;
379 		}
380 	}
381 
382 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
383 	return_VOID;
384 }
385 
386 /*******************************************************************************
387  *
388  * FUNCTION:    acpi_ns_delete_namespace_by_owner
389  *
390  * PARAMETERS:  owner_id    - All nodes with this owner will be deleted
391  *
392  * RETURN:      Status
393  *
394  * DESCRIPTION: Delete entries within the namespace that are owned by a
395  *              specific ID. Used to delete entire ACPI tables. All
396  *              reference counts are updated.
397  *
398  * MUTEX:       Locks namespace during deletion walk.
399  *
400  ******************************************************************************/
401 
402 void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
403 {
404 	struct acpi_namespace_node *child_node;
405 	struct acpi_namespace_node *deletion_node;
406 	struct acpi_namespace_node *parent_node;
407 	u32 level;
408 	acpi_status status;
409 
410 	ACPI_FUNCTION_TRACE_U32(ns_delete_namespace_by_owner, owner_id);
411 
412 	if (owner_id == 0) {
413 		return_VOID;
414 	}
415 
416 	/* Lock namespace for possible update */
417 
418 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
419 	if (ACPI_FAILURE(status)) {
420 		return_VOID;
421 	}
422 
423 	deletion_node = NULL;
424 	parent_node = acpi_gbl_root_node;
425 	child_node = NULL;
426 	level = 1;
427 
428 	/*
429 	 * Traverse the tree of nodes until we bubble back up
430 	 * to where we started.
431 	 */
432 	while (level > 0) {
433 		/*
434 		 * Get the next child of this parent node. When child_node is NULL,
435 		 * the first child of the parent is returned
436 		 */
437 		child_node = acpi_ns_get_next_node(parent_node, child_node);
438 
439 		if (deletion_node) {
440 			acpi_ns_delete_children(deletion_node);
441 			acpi_ns_remove_node(deletion_node);
442 			deletion_node = NULL;
443 		}
444 
445 		if (child_node) {
446 			if (child_node->owner_id == owner_id) {
447 
448 				/* Found a matching child node - detach any attached object */
449 
450 				acpi_ns_detach_object(child_node);
451 			}
452 
453 			/* Check if this node has any children */
454 
455 			if (child_node->child) {
456 				/*
457 				 * There is at least one child of this node,
458 				 * visit the node
459 				 */
460 				level++;
461 				parent_node = child_node;
462 				child_node = NULL;
463 			} else if (child_node->owner_id == owner_id) {
464 				deletion_node = child_node;
465 			}
466 		} else {
467 			/*
468 			 * No more children of this parent node.
469 			 * Move up to the grandparent.
470 			 */
471 			level--;
472 			if (level != 0) {
473 				if (parent_node->owner_id == owner_id) {
474 					deletion_node = parent_node;
475 				}
476 			}
477 
478 			/* New "last child" is this parent node */
479 
480 			child_node = parent_node;
481 
482 			/* Move up the tree to the grandparent */
483 
484 			parent_node = parent_node->parent;
485 		}
486 	}
487 
488 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
489 	return_VOID;
490 }
491