ACPI: ACPICA 20060623

Implemented a new acpi_spinlock type for the OSL lock
interfaces.  This allows the type to be customized to
the host OS for improved efficiency (since a spinlock is
usually a very small object.)

Implemented support for "ignored" bits in the ACPI
registers.  According to the ACPI specification, these
bits should be preserved when writing the registers via
a read/modify/write cycle. There are 3 bits preserved
in this manner: PM1_CONTROL[0] (SCI_EN), PM1_CONTROL[9],
and PM1_STATUS[11].
http://bugzilla.kernel.org/show_bug.cgi?id=3691

Implemented the initial deployment of new OSL mutex
interfaces.  Since some host operating systems have
separate mutex and semaphore objects, this feature was
requested. The base code now uses mutexes (and the new
mutex interfaces) wherever a binary semaphore was used
previously. However, for the current release, the mutex
interfaces are defined as macros to map them to the
existing semaphore interfaces.

Fixed several problems with the support for the control
method SyncLevel parameter. The SyncLevel now works
according to the ACPI specification and in concert with the
Mutex SyncLevel parameter, since the current SyncLevel is
a property of the executing thread. Mutual exclusion for
control methods is now implemented with a mutex instead
of a semaphore.

Fixed three instances of the use of the C shift operator
in the bitfield support code (exfldio.c) to avoid the use
of a shift value larger than the target data width. The
behavior of C compilers is undefined in this case and can
cause unpredictable results, and therefore the case must
be detected and avoided.  (Fiodor Suietov)

Added an info message whenever an SSDT or OEM table
is loaded dynamically via the Load() or LoadTable()
ASL operators. This should improve debugging capability
since it will show exactly what tables have been loaded
(beyond the tables present in the RSDT/XSDT.)

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/dispatcher/dsmethod.c b/drivers/acpi/dispatcher/dsmethod.c
index bc9aca4..a39a33f 100644
--- a/drivers/acpi/dispatcher/dsmethod.c
+++ b/drivers/acpi/dispatcher/dsmethod.c
@@ -52,6 +52,10 @@
 #define _COMPONENT          ACPI_DISPATCHER
 ACPI_MODULE_NAME("dsmethod")
 
+/* Local prototypes */
+static acpi_status
+acpi_ds_create_method_mutex(union acpi_operand_object *method_desc);
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ds_method_error
@@ -67,6 +71,7 @@
  *              Note: Allows the exception handler to change the status code
  *
  ******************************************************************************/
+
 acpi_status
 acpi_ds_method_error(acpi_status status, struct acpi_walk_state *walk_state)
 {
@@ -113,11 +118,51 @@
 
 /*******************************************************************************
  *
+ * FUNCTION:    acpi_ds_create_method_mutex
+ *
+ * PARAMETERS:  obj_desc            - The method object
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Create a mutex object for a serialized control method
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ds_create_method_mutex(union acpi_operand_object *method_desc)
+{
+	union acpi_operand_object *mutex_desc;
+	acpi_status status;
+
+	ACPI_FUNCTION_NAME(ds_create_method_mutex);
+
+	/* Create the new mutex object */
+
+	mutex_desc = acpi_ut_create_internal_object(ACPI_TYPE_MUTEX);
+	if (!mutex_desc) {
+		return_ACPI_STATUS(AE_NO_MEMORY);
+	}
+
+	/* Create the actual OS Mutex */
+
+	status = acpi_os_create_mutex(&mutex_desc->mutex.os_mutex);
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
+
+	mutex_desc->mutex.sync_level = method_desc->method.sync_level;
+	method_desc->method.mutex = mutex_desc;
+	return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
  * FUNCTION:    acpi_ds_begin_method_execution
  *
  * PARAMETERS:  method_node         - Node of the method
  *              obj_desc            - The method object
- *              calling_method_node - Caller of this method (if non-null)
+ *              walk_state          - current state, NULL if not yet executing
+ *                                    a method.
  *
  * RETURN:      Status
  *
@@ -128,9 +173,9 @@
  ******************************************************************************/
 
 acpi_status
-acpi_ds_begin_method_execution(struct acpi_namespace_node * method_node,
-			       union acpi_operand_object * obj_desc,
-			       struct acpi_namespace_node * calling_method_node)
+acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node,
+			       union acpi_operand_object *obj_desc,
+			       struct acpi_walk_state *walk_state)
 {
 	acpi_status status = AE_OK;
 
@@ -149,35 +194,80 @@
 	}
 
 	/*
-	 * If there is a concurrency limit on this method, we need to
-	 * obtain a unit from the method semaphore.
+	 * If this method is serialized, we need to acquire the method mutex.
 	 */
-	if (obj_desc->method.semaphore) {
+	if (obj_desc->method.method_flags & AML_METHOD_SERIALIZED) {
 		/*
-		 * Allow recursive method calls, up to the reentrancy/concurrency
-		 * limit imposed by the SERIALIZED rule and the sync_level method
-		 * parameter.
-		 *
-		 * The point of this code is to avoid permanently blocking a
-		 * thread that is making recursive method calls.
+		 * Create a mutex for the method if it is defined to be Serialized
+		 * and a mutex has not already been created. We defer the mutex creation
+		 * until a method is actually executed, to minimize the object count
 		 */
-		if (method_node == calling_method_node) {
-			if (obj_desc->method.thread_count >=
-			    obj_desc->method.concurrency) {
-				return_ACPI_STATUS(AE_AML_METHOD_LIMIT);
+		if (!obj_desc->method.mutex) {
+			status = acpi_ds_create_method_mutex(obj_desc);
+			if (ACPI_FAILURE(status)) {
+				return_ACPI_STATUS(status);
 			}
 		}
 
 		/*
-		 * Get a unit from the method semaphore. This releases the
-		 * interpreter if we block (then reacquires it)
+		 * The current_sync_level (per-thread) must be less than or equal to
+		 * the sync level of the method. This mechanism provides some
+		 * deadlock prevention
+		 *
+		 * Top-level method invocation has no walk state at this point
 		 */
-		status =
-		    acpi_ex_system_wait_semaphore(obj_desc->method.semaphore,
-						  ACPI_WAIT_FOREVER);
-		if (ACPI_FAILURE(status)) {
-			return_ACPI_STATUS(status);
+		if (walk_state &&
+		    (walk_state->thread->current_sync_level >
+		     obj_desc->method.mutex->mutex.sync_level)) {
+			ACPI_ERROR((AE_INFO,
+				    "Cannot acquire Mutex for method [%4.4s], current SyncLevel is too large (%d)",
+				    acpi_ut_get_node_name(method_node),
+				    walk_state->thread->current_sync_level));
+
+			return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
 		}
+
+		/*
+		 * Obtain the method mutex if necessary. Do not acquire mutex for a
+		 * recursive call.
+		 */
+		if (!walk_state ||
+		    !obj_desc->method.mutex->mutex.owner_thread ||
+		    (walk_state->thread !=
+		     obj_desc->method.mutex->mutex.owner_thread)) {
+			/*
+			 * Acquire the method mutex. This releases the interpreter if we
+			 * block (and reacquires it before it returns)
+			 */
+			status =
+			    acpi_ex_system_wait_mutex(obj_desc->method.mutex->
+						      mutex.os_mutex,
+						      ACPI_WAIT_FOREVER);
+			if (ACPI_FAILURE(status)) {
+				return_ACPI_STATUS(status);
+			}
+
+			/* Update the mutex and walk info and save the original sync_level */
+
+			if (walk_state) {
+				obj_desc->method.mutex->mutex.
+				    original_sync_level =
+				    walk_state->thread->current_sync_level;
+
+				obj_desc->method.mutex->mutex.owner_thread =
+				    walk_state->thread;
+				walk_state->thread->current_sync_level =
+				    obj_desc->method.sync_level;
+			} else {
+				obj_desc->method.mutex->mutex.
+				    original_sync_level =
+				    obj_desc->method.mutex->mutex.sync_level;
+			}
+		}
+
+		/* Always increase acquisition depth */
+
+		obj_desc->method.mutex->mutex.acquisition_depth++;
 	}
 
 	/*
@@ -200,10 +290,10 @@
 	return_ACPI_STATUS(status);
 
       cleanup:
-	/* On error, must signal the method semaphore if present */
+	/* On error, must release the method mutex (if present) */
 
-	if (obj_desc->method.semaphore) {
-		(void)acpi_os_signal_semaphore(obj_desc->method.semaphore, 1);
+	if (obj_desc->method.mutex) {
+		acpi_os_release_mutex(obj_desc->method.mutex->mutex.os_mutex);
 	}
 	return_ACPI_STATUS(status);
 }
@@ -253,10 +343,10 @@
 		return_ACPI_STATUS(AE_NULL_OBJECT);
 	}
 
-	/* Init for new method, possibly wait on concurrency semaphore */
+	/* Init for new method, possibly wait on method mutex */
 
 	status = acpi_ds_begin_method_execution(method_node, obj_desc,
-						this_walk_state->method_node);
+						this_walk_state);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}
@@ -478,6 +568,8 @@
  *              created, delete all locals and arguments, and delete the parse
  *              tree if requested.
  *
+ * MUTEX:       Interpreter is locked
+ *
  ******************************************************************************/
 
 void
@@ -503,26 +595,21 @@
 	}
 
 	/*
-	 * Lock the parser while we terminate this method.
-	 * If this is the last thread executing the method,
-	 * we have additional cleanup to perform
+	 * If method is serialized, release the mutex and restore the
+	 * current sync level for this thread
 	 */
-	status = acpi_ut_acquire_mutex(ACPI_MTX_CONTROL_METHOD);
-	if (ACPI_FAILURE(status)) {
-		return_VOID;
-	}
+	if (method_desc->method.mutex) {
 
-	/* Signal completion of the execution of this method if necessary */
+		/* Acquisition Depth handles recursive calls */
 
-	if (method_desc->method.semaphore) {
-		status =
-		    acpi_os_signal_semaphore(method_desc->method.semaphore, 1);
-		if (ACPI_FAILURE(status)) {
+		method_desc->method.mutex->mutex.acquisition_depth--;
+		if (!method_desc->method.mutex->mutex.acquisition_depth) {
+			walk_state->thread->current_sync_level =
+			    method_desc->method.mutex->mutex.
+			    original_sync_level;
 
-			/* Ignore error and continue */
-
-			ACPI_EXCEPTION((AE_INFO, status,
-					"Could not signal method semaphore"));
+			acpi_os_release_mutex(method_desc->method.mutex->mutex.
+					      os_mutex);
 		}
 	}
 
@@ -537,7 +624,7 @@
 
 		status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 		if (ACPI_FAILURE(status)) {
-			goto exit;
+			return_VOID;
 		}
 
 		/*
@@ -580,18 +667,16 @@
 		/*
 		 * Support to dynamically change a method from not_serialized to
 		 * Serialized if it appears that the method is incorrectly written and
-		 * does not support multiple thread execution.  The best example of this
-		 * is if such a method creates namespace objects and blocks.  A second
+		 * does not support multiple thread execution. The best example of this
+		 * is if such a method creates namespace objects and blocks. A second
 		 * thread will fail with an AE_ALREADY_EXISTS exception
 		 *
 		 * This code is here because we must wait until the last thread exits
 		 * before creating the synchronization semaphore.
 		 */
-		if ((method_desc->method.concurrency == 1) &&
-		    (!method_desc->method.semaphore)) {
-			status = acpi_os_create_semaphore(1, 1,
-							  &method_desc->method.
-							  semaphore);
+		if ((method_desc->method.method_flags & AML_METHOD_SERIALIZED)
+		    && (!method_desc->method.mutex)) {
+			status = acpi_ds_create_method_mutex(method_desc);
 		}
 
 		/* No more threads, we can free the owner_id */
@@ -599,144 +684,5 @@
 		acpi_ut_release_owner_id(&method_desc->method.owner_id);
 	}
 
-      exit:
-	(void)acpi_ut_release_mutex(ACPI_MTX_CONTROL_METHOD);
 	return_VOID;
 }
-
-#ifdef ACPI_INIT_PARSE_METHODS
-	/*
-	 * Note 11/2005: Removed this code to parse all methods during table
-	 * load because it causes problems if there are any errors during the
-	 * parse. Also, it seems like overkill and we probably don't want to
-	 * abort a table load because of an issue with a single method.
-	 */
-
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ds_parse_method
- *
- * PARAMETERS:  Node        - Method node
- *
- * RETURN:      Status
- *
- * DESCRIPTION: Parse the AML that is associated with the method.
- *
- * MUTEX:       Assumes parser is locked
- *
- ******************************************************************************/
-
-acpi_status acpi_ds_parse_method(struct acpi_namespace_node *node)
-{
-	acpi_status status;
-	union acpi_operand_object *obj_desc;
-	union acpi_parse_object *op;
-	struct acpi_walk_state *walk_state;
-
-	ACPI_FUNCTION_TRACE_PTR(ds_parse_method, node);
-
-	/* Parameter Validation */
-
-	if (!node) {
-		return_ACPI_STATUS(AE_NULL_ENTRY);
-	}
-
-	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
-			  "**** Parsing [%4.4s] **** NamedObj=%p\n",
-			  acpi_ut_get_node_name(node), node));
-
-	/* Extract the method object from the method Node */
-
-	obj_desc = acpi_ns_get_attached_object(node);
-	if (!obj_desc) {
-		return_ACPI_STATUS(AE_NULL_OBJECT);
-	}
-
-	/* Create a mutex for the method if there is a concurrency limit */
-
-	if ((obj_desc->method.concurrency != ACPI_INFINITE_CONCURRENCY) &&
-	    (!obj_desc->method.semaphore)) {
-		status = acpi_os_create_semaphore(obj_desc->method.concurrency,
-						  obj_desc->method.concurrency,
-						  &obj_desc->method.semaphore);
-		if (ACPI_FAILURE(status)) {
-			return_ACPI_STATUS(status);
-		}
-	}
-
-	/*
-	 * Allocate a new parser op to be the root of the parsed
-	 * method tree
-	 */
-	op = acpi_ps_alloc_op(AML_METHOD_OP);
-	if (!op) {
-		return_ACPI_STATUS(AE_NO_MEMORY);
-	}
-
-	/* Init new op with the method name and pointer back to the Node */
-
-	acpi_ps_set_name(op, node->name.integer);
-	op->common.node = node;
-
-	/*
-	 * Get a new owner_id for objects created by this method. Namespace
-	 * objects (such as Operation Regions) can be created during the
-	 * first pass parse.
-	 */
-	status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id);
-	if (ACPI_FAILURE(status)) {
-		goto cleanup;
-	}
-
-	/* Create and initialize a new walk state */
-
-	walk_state =
-	    acpi_ds_create_walk_state(obj_desc->method.owner_id, NULL, NULL,
-				      NULL);
-	if (!walk_state) {
-		status = AE_NO_MEMORY;
-		goto cleanup2;
-	}
-
-	status = acpi_ds_init_aml_walk(walk_state, op, node,
-				       obj_desc->method.aml_start,
-				       obj_desc->method.aml_length, NULL, 1);
-	if (ACPI_FAILURE(status)) {
-		acpi_ds_delete_walk_state(walk_state);
-		goto cleanup2;
-	}
-
-	/*
-	 * Parse the method, first pass
-	 *
-	 * The first pass load is where newly declared named objects are added into
-	 * the namespace.  Actual evaluation of the named objects (what would be
-	 * called a "second pass") happens during the actual execution of the
-	 * method so that operands to the named objects can take on dynamic
-	 * run-time values.
-	 */
-	status = acpi_ps_parse_aml(walk_state);
-	if (ACPI_FAILURE(status)) {
-		goto cleanup2;
-	}
-
-	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
-			  "**** [%4.4s] Parsed **** NamedObj=%p Op=%p\n",
-			  acpi_ut_get_node_name(node), node, op));
-
-	/*
-	 * Delete the parse tree. We simply re-parse the method for every
-	 * execution since there isn't much overhead (compared to keeping lots
-	 * of parse trees around)
-	 */
-	acpi_ns_delete_namespace_subtree(node);
-	acpi_ns_delete_namespace_by_owner(obj_desc->method.owner_id);
-
-      cleanup2:
-	acpi_ut_release_owner_id(&obj_desc->method.owner_id);
-
-      cleanup:
-	acpi_ps_delete_parse_tree(op);
-	return_ACPI_STATUS(status);
-}
-#endif