1 files changed, 396 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/nssearch.c b/drivers/acpi/acpica/nssearch.c
new file mode 100644
index 000000000..f594ab75a
--- /dev/null
+++ b/drivers/acpi/acpica/nssearch.c
@@ -0,0 +1,396 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/*******************************************************************************
+ *
+ * Module Name: nssearch - Namespace search
+ *
+ ******************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acnamesp.h"
+
+#ifdef ACPI_ASL_COMPILER
+#include "amlcode.h"
+#endif
+
+#define _COMPONENT          ACPI_NAMESPACE
+ACPI_MODULE_NAME("nssearch")
+
+/* Local prototypes */
+static acpi_status
+acpi_ns_search_parent_tree(u32 target_name,
+			   struct acpi_namespace_node *node,
+			   acpi_object_type type,
+			   struct acpi_namespace_node **return_node);
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_search_one_scope
+ *
+ * PARAMETERS:  target_name     - Ascii ACPI name to search for
+ *              parent_node     - Starting node where search will begin
+ *              type            - Object type to match
+ *              return_node     - Where the matched Named obj is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Search a single level of the namespace. Performs a
+ *              simple search of the specified level, and does not add
+ *              entries or search parents.
+ *
+ *
+ *      Named object lists are built (and subsequently dumped) in the
+ *      order in which the names are encountered during the namespace load;
+ *
+ *      All namespace searching is linear in this implementation, but
+ *      could be easily modified to support any improved search
+ *      algorithm. However, the linear search was chosen for simplicity
+ *      and because the trees are small and the other interpreter
+ *      execution overhead is relatively high.
+ *
+ *      Note: CPU execution analysis has shown that the AML interpreter spends
+ *      a very small percentage of its time searching the namespace. Therefore,
+ *      the linear search seems to be sufficient, as there would seem to be
+ *      little value in improving the search.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ns_search_one_scope(u32 target_name,
+			 struct acpi_namespace_node *parent_node,
+			 acpi_object_type type,
+			 struct acpi_namespace_node **return_node)
+{
+	struct acpi_namespace_node *node;
+
+	ACPI_FUNCTION_TRACE(ns_search_one_scope);
+
+#ifdef ACPI_DEBUG_OUTPUT
+	if (ACPI_LV_NAMES & acpi_dbg_level) {
+		char *scope_name;
+
+		scope_name = acpi_ns_get_normalized_pathname(parent_node, TRUE);
+		if (scope_name) {
+			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+					  "Searching %s (%p) For [%4.4s] (%s)\n",
+					  scope_name, parent_node,
+					  ACPI_CAST_PTR(char, &target_name),
+					  acpi_ut_get_type_name(type)));
+
+			ACPI_FREE(scope_name);
+		}
+	}
+#endif
+
+	/*
+	 * Search for name at this namespace level, which is to say that we
+	 * must search for the name among the children of this object
+	 */
+	node = parent_node->child;
+	while (node) {
+
+		/* Check for match against the name */
+
+		if (node->name.integer == target_name) {
+
+			/* Resolve a control method alias if any */
+
+			if (acpi_ns_get_type(node) ==
+			    ACPI_TYPE_LOCAL_METHOD_ALIAS) {
+				node =
+				    ACPI_CAST_PTR(struct acpi_namespace_node,
+						  node->object);
+			}
+
+			/* Found matching entry */
+
+			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+					  "Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n",
+					  ACPI_CAST_PTR(char, &target_name),
+					  acpi_ut_get_type_name(node->type),
+					  node,
+					  acpi_ut_get_node_name(parent_node),
+					  parent_node));
+
+			*return_node = node;
+			return_ACPI_STATUS(AE_OK);
+		}
+
+		/* Didn't match name, move on to the next peer object */
+
+		node = node->peer;
+	}
+
+	/* Searched entire namespace level, not found */
+
+	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+			  "Name [%4.4s] (%s) not found in search in scope [%4.4s] "
+			  "%p first child %p\n",
+			  ACPI_CAST_PTR(char, &target_name),
+			  acpi_ut_get_type_name(type),
+			  acpi_ut_get_node_name(parent_node), parent_node,
+			  parent_node->child));
+
+	return_ACPI_STATUS(AE_NOT_FOUND);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_search_parent_tree
+ *
+ * PARAMETERS:  target_name     - Ascii ACPI name to search for
+ *              node            - Starting node where search will begin
+ *              type            - Object type to match
+ *              return_node     - Where the matched Node is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Called when a name has not been found in the current namespace
+ *              level. Before adding it or giving up, ACPI scope rules require
+ *              searching enclosing scopes in cases identified by acpi_ns_local().
+ *
+ *              "A name is located by finding the matching name in the current
+ *              name space, and then in the parent name space. If the parent
+ *              name space does not contain the name, the search continues
+ *              recursively until either the name is found or the name space
+ *              does not have a parent (the root of the name space). This
+ *              indicates that the name is not found" (From ACPI Specification,
+ *              section 5.3)
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ns_search_parent_tree(u32 target_name,
+			   struct acpi_namespace_node *node,
+			   acpi_object_type type,
+			   struct acpi_namespace_node **return_node)
+{
+	acpi_status status;
+	struct acpi_namespace_node *parent_node;
+
+	ACPI_FUNCTION_TRACE(ns_search_parent_tree);
+
+	parent_node = node->parent;
+
+	/*
+	 * If there is no parent (i.e., we are at the root) or type is "local",
+	 * we won't be searching the parent tree.
+	 */
+	if (!parent_node) {
+		ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "[%4.4s] has no parent\n",
+				  ACPI_CAST_PTR(char, &target_name)));
+		return_ACPI_STATUS(AE_NOT_FOUND);
+	}
+
+	if (acpi_ns_local(type)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+				  "[%4.4s] type [%s] must be local to this scope (no parent search)\n",
+				  ACPI_CAST_PTR(char, &target_name),
+				  acpi_ut_get_type_name(type)));
+		return_ACPI_STATUS(AE_NOT_FOUND);
+	}
+
+	/* Search the parent tree */
+
+	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+			  "Searching parent [%4.4s] for [%4.4s]\n",
+			  acpi_ut_get_node_name(parent_node),
+			  ACPI_CAST_PTR(char, &target_name)));
+
+	/* Search parents until target is found or we have backed up to the root */
+
+	while (parent_node) {
+		/*
+		 * Search parent scope. Use TYPE_ANY because we don't care about the
+		 * object type at this point, we only care about the existence of
+		 * the actual name we are searching for. Typechecking comes later.
+		 */
+		status =
+		    acpi_ns_search_one_scope(target_name, parent_node,
+					     ACPI_TYPE_ANY, return_node);
+		if (ACPI_SUCCESS(status)) {
+			return_ACPI_STATUS(status);
+		}
+
+		/* Not found here, go up another level (until we reach the root) */
+
+		parent_node = parent_node->parent;
+	}
+
+	/* Not found in parent tree */
+
+	return_ACPI_STATUS(AE_NOT_FOUND);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_search_and_enter
+ *
+ * PARAMETERS:  target_name         - Ascii ACPI name to search for (4 chars)
+ *              walk_state          - Current state of the walk
+ *              node                - Starting node where search will begin
+ *              interpreter_mode    - Add names only in ACPI_MODE_LOAD_PASS_x.
+ *                                    Otherwise,search only.
+ *              type                - Object type to match
+ *              flags               - Flags describing the search restrictions
+ *              return_node         - Where the Node is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Search for a name segment in a single namespace level,
+ *              optionally adding it if it is not found. If the passed
+ *              Type is not Any and the type previously stored in the
+ *              entry was Any (i.e. unknown), update the stored type.
+ *
+ *              In ACPI_IMODE_EXECUTE, search only.
+ *              In other modes, search and add if not found.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ns_search_and_enter(u32 target_name,
+			 struct acpi_walk_state *walk_state,
+			 struct acpi_namespace_node *node,
+			 acpi_interpreter_mode interpreter_mode,
+			 acpi_object_type type,
+			 u32 flags, struct acpi_namespace_node **return_node)
+{
+	acpi_status status;
+	struct acpi_namespace_node *new_node;
+
+	ACPI_FUNCTION_TRACE(ns_search_and_enter);
+
+	/* Parameter validation */
+
+	if (!node || !target_name || !return_node) {
+		ACPI_ERROR((AE_INFO,
+			    "Null parameter: Node %p Name 0x%X ReturnNode %p",
+			    node, target_name, return_node));
+		return_ACPI_STATUS(AE_BAD_PARAMETER);
+	}
+
+	/*
+	 * Name must consist of valid ACPI characters. We will repair the name if
+	 * necessary because we don't want to abort because of this, but we want
+	 * all namespace names to be printable. A warning message is appropriate.
+	 *
+	 * This issue came up because there are in fact machines that exhibit
+	 * this problem, and we want to be able to enable ACPI support for them,
+	 * even though there are a few bad names.
+	 */
+	acpi_ut_repair_name(ACPI_CAST_PTR(char, &target_name));
+
+	/* Try to find the name in the namespace level specified by the caller */
+
+	*return_node = ACPI_ENTRY_NOT_FOUND;
+	status = acpi_ns_search_one_scope(target_name, node, type, return_node);
+	if (status != AE_NOT_FOUND) {
+		/*
+		 * If we found it AND the request specifies that a find is an error,
+		 * return the error
+		 */
+		if (status == AE_OK) {
+
+			/* The node was found in the namespace */
+
+			/*
+			 * If the namespace override feature is enabled for this node,
+			 * delete any existing attached sub-object and make the node
+			 * look like a new node that is owned by the override table.
+			 */
+			if (flags & ACPI_NS_OVERRIDE_IF_FOUND) {
+				ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+						  "Namespace override: %4.4s pass %u type %X Owner %X\n",
+						  ACPI_CAST_PTR(char,
+								&target_name),
+						  interpreter_mode,
+						  (*return_node)->type,
+						  walk_state->owner_id));
+
+				acpi_ns_delete_children(*return_node);
+				if (acpi_gbl_runtime_namespace_override) {
+					acpi_ut_remove_reference((*return_node)->object);
+					(*return_node)->object = NULL;
+					(*return_node)->owner_id =
+					    walk_state->owner_id;
+				} else {
+					acpi_ns_remove_node(*return_node);
+					*return_node = ACPI_ENTRY_NOT_FOUND;
+				}
+			}
+
+			/* Return an error if we don't expect to find the object */
+
+			else if (flags & ACPI_NS_ERROR_IF_FOUND) {
+				status = AE_ALREADY_EXISTS;
+			}
+		}
+#ifdef ACPI_ASL_COMPILER
+		if (*return_node && (*return_node)->type == ACPI_TYPE_ANY) {
+			(*return_node)->flags |= ANOBJ_IS_EXTERNAL;
+		}
+#endif
+
+		/* Either found it or there was an error: finished either way */
+
+		return_ACPI_STATUS(status);
+	}
+
+	/*
+	 * The name was not found. If we are NOT performing the first pass
+	 * (name entry) of loading the namespace, search the parent tree (all the
+	 * way to the root if necessary.) We don't want to perform the parent
+	 * search when the namespace is actually being loaded. We want to perform
+	 * the search when namespace references are being resolved (load pass 2)
+	 * and during the execution phase.
+	 */
+	if ((interpreter_mode != ACPI_IMODE_LOAD_PASS1) &&
+	    (flags & ACPI_NS_SEARCH_PARENT)) {
+		/*
+		 * Not found at this level - search parent tree according to the
+		 * ACPI specification
+		 */
+		status =
+		    acpi_ns_search_parent_tree(target_name, node, type,
+					       return_node);
+		if (ACPI_SUCCESS(status)) {
+			return_ACPI_STATUS(status);
+		}
+	}
+
+	/* In execute mode, just search, never add names. Exit now */
+
+	if (interpreter_mode == ACPI_IMODE_EXECUTE) {
+		ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+				  "%4.4s Not found in %p [Not adding]\n",
+				  ACPI_CAST_PTR(char, &target_name), node));
+
+		return_ACPI_STATUS(AE_NOT_FOUND);
+	}
+
+	/* Create the new named object */
+
+	new_node = acpi_ns_create_node(target_name);
+	if (!new_node) {
+		return_ACPI_STATUS(AE_NO_MEMORY);
+	}
+#ifdef ACPI_ASL_COMPILER
+
+	/* Node is an object defined by an External() statement */
+
+	if (flags & ACPI_NS_EXTERNAL ||
+	    (walk_state && walk_state->opcode == AML_SCOPE_OP)) {
+		new_node->flags |= ANOBJ_IS_EXTERNAL;
+	}
+#endif
+
+	if (flags & ACPI_NS_TEMPORARY) {
+		new_node->flags |= ANOBJ_TEMPORARY;
+	}
+
+	/* Install the new object into the parent's list of children */
+
+	acpi_ns_install_node(walk_state, node, new_node, type);
+	*return_node = new_node;
+	return_ACPI_STATUS(AE_OK);
+}