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path: root/drivers/acpi/acpica/nswalk.c
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Diffstat (limited to 'drivers/acpi/acpica/nswalk.c')
-rw-r--r--drivers/acpi/acpica/nswalk.c200
1 files changed, 117 insertions, 83 deletions
diff --git a/drivers/acpi/acpica/nswalk.c b/drivers/acpi/acpica/nswalk.c
index 35539df5c75d..d7e6b52b4482 100644
--- a/drivers/acpi/acpica/nswalk.c
+++ b/drivers/acpi/acpica/nswalk.c
@@ -165,24 +165,27 @@ struct acpi_namespace_node *acpi_ns_get_next_node_typed(acpi_object_type type,
* max_depth - Depth to which search is to reach
* Flags - Whether to unlock the NS before invoking
* the callback routine
- * user_function - Called when an object of "Type" is found
- * Context - Passed to user function
- * return_value - from the user_function if terminated early.
- * Otherwise, returns NULL.
+ * pre_order_visit - Called during tree pre-order visit
+ * when an object of "Type" is found
+ * post_order_visit - Called during tree post-order visit
+ * when an object of "Type" is found
+ * Context - Passed to user function(s) above
+ * return_value - from the user_function if terminated
+ * early. Otherwise, returns NULL.
* RETURNS: Status
*
* DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
* starting (and ending) at the node specified by start_handle.
- * The user_function is called whenever a node that matches
- * the type parameter is found. If the user function returns
+ * The callback function is called whenever a node that matches
+ * the type parameter is found. If the callback function returns
* a non-zero value, the search is terminated immediately and
* this value is returned to the caller.
*
* The point of this procedure is to provide a generic namespace
* walk routine that can be called from multiple places to
- * provide multiple services; the User Function can be tailored
- * to each task, whether it is a print function, a compare
- * function, etc.
+ * provide multiple services; the callback function(s) can be
+ * tailored to each task, whether it is a print function,
+ * a compare function, etc.
*
******************************************************************************/
@@ -191,7 +194,8 @@ acpi_ns_walk_namespace(acpi_object_type type,
acpi_handle start_node,
u32 max_depth,
u32 flags,
- acpi_walk_callback user_function,
+ acpi_walk_callback pre_order_visit,
+ acpi_walk_callback post_order_visit,
void *context, void **return_value)
{
acpi_status status;
@@ -200,6 +204,7 @@ acpi_ns_walk_namespace(acpi_object_type type,
struct acpi_namespace_node *parent_node;
acpi_object_type child_type;
u32 level;
+ u8 node_previously_visited = FALSE;
ACPI_FUNCTION_TRACE(ns_walk_namespace);
@@ -212,7 +217,7 @@ acpi_ns_walk_namespace(acpi_object_type type,
/* Null child means "get first node" */
parent_node = start_node;
- child_node = NULL;
+ child_node = acpi_ns_get_next_node(parent_node, NULL);
child_type = ACPI_TYPE_ANY;
level = 1;
@@ -221,102 +226,129 @@ acpi_ns_walk_namespace(acpi_object_type type,
* started. When Level is zero, the loop is done because we have
* bubbled up to (and passed) the original parent handle (start_entry)
*/
- while (level > 0) {
+ while (level > 0 && child_node) {
+ status = AE_OK;
- /* Get the next node in this scope. Null if not found */
+ /* Found next child, get the type if we are not searching for ANY */
- status = AE_OK;
- child_node = acpi_ns_get_next_node(parent_node, child_node);
- if (child_node) {
+ if (type != ACPI_TYPE_ANY) {
+ child_type = child_node->type;
+ }
- /* Found next child, get the type if we are not searching for ANY */
+ /*
+ * Ignore all temporary namespace nodes (created during control
+ * method execution) unless told otherwise. These temporary nodes
+ * can cause a race condition because they can be deleted during
+ * the execution of the user function (if the namespace is
+ * unlocked before invocation of the user function.) Only the
+ * debugger namespace dump will examine the temporary nodes.
+ */
+ if ((child_node->flags & ANOBJ_TEMPORARY) &&
+ !(flags & ACPI_NS_WALK_TEMP_NODES)) {
+ status = AE_CTRL_DEPTH;
+ }
- if (type != ACPI_TYPE_ANY) {
- child_type = child_node->type;
- }
+ /* Type must match requested type */
+ else if (child_type == type) {
/*
- * Ignore all temporary namespace nodes (created during control
- * method execution) unless told otherwise. These temporary nodes
- * can cause a race condition because they can be deleted during
- * the execution of the user function (if the namespace is
- * unlocked before invocation of the user function.) Only the
- * debugger namespace dump will examine the temporary nodes.
+ * Found a matching node, invoke the user callback function.
+ * Unlock the namespace if flag is set.
*/
- if ((child_node->flags & ANOBJ_TEMPORARY) &&
- !(flags & ACPI_NS_WALK_TEMP_NODES)) {
- status = AE_CTRL_DEPTH;
+ if (flags & ACPI_NS_WALK_UNLOCK) {
+ mutex_status =
+ acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+ if (ACPI_FAILURE(mutex_status)) {
+ return_ACPI_STATUS(mutex_status);
+ }
}
- /* Type must match requested type */
-
- else if (child_type == type) {
- /*
- * Found a matching node, invoke the user callback function.
- * Unlock the namespace if flag is set.
- */
- if (flags & ACPI_NS_WALK_UNLOCK) {
- mutex_status =
- acpi_ut_release_mutex
- (ACPI_MTX_NAMESPACE);
- if (ACPI_FAILURE(mutex_status)) {
- return_ACPI_STATUS
- (mutex_status);
- }
+ /*
+ * Invoke the user function, either pre-order or post-order
+ * or both.
+ */
+ if (!node_previously_visited) {
+ if (pre_order_visit) {
+ status =
+ pre_order_visit(child_node, level,
+ context,
+ return_value);
}
+ } else {
+ if (post_order_visit) {
+ status =
+ post_order_visit(child_node, level,
+ context,
+ return_value);
+ }
+ }
- status =
- user_function(child_node, level, context,
- return_value);
-
- if (flags & ACPI_NS_WALK_UNLOCK) {
- mutex_status =
- acpi_ut_acquire_mutex
- (ACPI_MTX_NAMESPACE);
- if (ACPI_FAILURE(mutex_status)) {
- return_ACPI_STATUS
- (mutex_status);
- }
+ if (flags & ACPI_NS_WALK_UNLOCK) {
+ mutex_status =
+ acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+ if (ACPI_FAILURE(mutex_status)) {
+ return_ACPI_STATUS(mutex_status);
}
+ }
- switch (status) {
- case AE_OK:
- case AE_CTRL_DEPTH:
+ switch (status) {
+ case AE_OK:
+ case AE_CTRL_DEPTH:
- /* Just keep going */
- break;
+ /* Just keep going */
+ break;
- case AE_CTRL_TERMINATE:
+ case AE_CTRL_TERMINATE:
- /* Exit now, with OK status */
+ /* Exit now, with OK status */
- return_ACPI_STATUS(AE_OK);
+ return_ACPI_STATUS(AE_OK);
- default:
+ default:
- /* All others are valid exceptions */
+ /* All others are valid exceptions */
- return_ACPI_STATUS(status);
- }
+ return_ACPI_STATUS(status);
+ }
+ }
+
+ /*
+ * Depth first search: Attempt to go down another level in the
+ * namespace if we are allowed to. Don't go any further if we have
+ * reached the caller specified maximum depth or if the user
+ * function has specified that the maximum depth has been reached.
+ */
+ if (!node_previously_visited &&
+ (level < max_depth) && (status != AE_CTRL_DEPTH)) {
+ if (child_node->child) {
+
+ /* There is at least one child of this node, visit it */
+
+ level++;
+ parent_node = child_node;
+ child_node =
+ acpi_ns_get_next_node(parent_node, NULL);
+ continue;
}
+ }
- /*
- * Depth first search: Attempt to go down another level in the
- * namespace if we are allowed to. Don't go any further if we have
- * reached the caller specified maximum depth or if the user
- * function has specified that the maximum depth has been reached.
- */
- if ((level < max_depth) && (status != AE_CTRL_DEPTH)) {
- if (child_node->child) {
+ /* No more children, re-visit this node */
- /* There is at least one child of this node, visit it */
+ if (!node_previously_visited) {
+ node_previously_visited = TRUE;
+ continue;
+ }
- level++;
- parent_node = child_node;
- child_node = NULL;
- }
- }
- } else {
+ /* No more children, visit peers */
+
+ child_node = acpi_ns_get_next_node(parent_node, child_node);
+ if (child_node) {
+ node_previously_visited = FALSE;
+ }
+
+ /* No peers, re-visit parent */
+
+ else {
/*
* No more children of this node (acpi_ns_get_next_node failed), go
* back upwards in the namespace tree to the node's parent.
@@ -324,6 +356,8 @@ acpi_ns_walk_namespace(acpi_object_type type,
level--;
child_node = parent_node;
parent_node = acpi_ns_get_parent_node(parent_node);
+
+ node_previously_visited = TRUE;
}
}