1 files changed, 112 insertions, 74 deletions

diff --git a/drivers/acpi/acpica/utdelete.c b/drivers/acpi/acpica/utdelete.c
index 798105443d0..a3516de213f 100644
--- a/drivers/acpi/acpica/utdelete.c
+++ b/drivers/acpi/acpica/utdelete.c
@@ -5,7 +5,7 @@
  ******************************************************************************/
 
 /*
- * Copyright (C) 2000 - 2012, Intel Corp.
+ * Copyright (C) 2000 - 2014, Intel Corp.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -75,6 +75,7 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
 	union acpi_operand_object *handler_desc;
 	union acpi_operand_object *second_desc;
 	union acpi_operand_object *next_desc;
+	union acpi_operand_object *start_desc;
 	union acpi_operand_object **last_obj_ptr;
 
 	ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object);
@@ -235,10 +236,11 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
 			if (handler_desc) {
 				next_desc =
 				    handler_desc->address_space.region_list;
+				start_desc = next_desc;
 				last_obj_ptr =
 				    &handler_desc->address_space.region_list;
 
-				/* Remove the region object from the handler's list */
+				/* Remove the region object from the handler list */
 
 				while (next_desc) {
 					if (next_desc == object) {
@@ -247,10 +249,19 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
 						break;
 					}
 
-					/* Walk the linked list of handler */
+					/* Walk the linked list of handlers */
 
 					last_obj_ptr = &next_desc->region.next;
 					next_desc = next_desc->region.next;
+
+					/* Prevent infinite loop if list is corrupted */
+
+					if (next_desc == start_desc) {
+						ACPI_ERROR((AE_INFO,
+							    "Circular region list in address handler object %p",
+							    handler_desc));
+						return_VOID;
+					}
 				}
 
 				if (handler_desc->address_space.handler_flags &
@@ -303,6 +314,7 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
 		break;
 
 	default:
+
 		break;
 	}
 
@@ -340,7 +352,7 @@ void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
 {
 	union acpi_operand_object **internal_obj;
 
-	ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
+	ACPI_FUNCTION_ENTRY();
 
 	/* Walk the null-terminated internal list */
 
@@ -351,7 +363,7 @@ void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
 	/* Free the combined parameter pointer list and object array */
 
 	ACPI_FREE(obj_list);
-	return_VOID;
+	return;
 }
 
 /*******************************************************************************
@@ -359,19 +371,20 @@ void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
  * FUNCTION:    acpi_ut_update_ref_count
  *
  * PARAMETERS:  object          - Object whose ref count is to be updated
- *              action          - What to do
+ *              action          - What to do (REF_INCREMENT or REF_DECREMENT)
  *
- * RETURN:      New ref count
+ * RETURN:      None. Sets new reference count within the object
  *
- * DESCRIPTION: Modify the ref count and return it.
+ * DESCRIPTION: Modify the reference count for an internal acpi object
  *
  ******************************************************************************/
 
 static void
 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
 {
-	u16 count;
-	u16 new_count;
+	u16 original_count;
+	u16 new_count = 0;
+	acpi_cpu_flags lock_flags;
 
 	ACPI_FUNCTION_NAME(ut_update_ref_count);
 
@@ -379,76 +392,79 @@ acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
 		return;
 	}
 
-	count = object->common.reference_count;
-	new_count = count;
-
 	/*
-	 * Perform the reference count action (increment, decrement, force delete)
+	 * Always get the reference count lock. Note: Interpreter and/or
+	 * Namespace is not always locked when this function is called.
 	 */
+	lock_flags = acpi_os_acquire_lock(acpi_gbl_reference_count_lock);
+	original_count = object->common.reference_count;
+
+	/* Perform the reference count action (increment, decrement) */
+
 	switch (action) {
 	case REF_INCREMENT:
 
-		new_count++;
+		new_count = original_count + 1;
 		object->common.reference_count = new_count;
+		acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
+
+		/* The current reference count should never be zero here */
+
+		if (!original_count) {
+			ACPI_WARNING((AE_INFO,
+				      "Obj %p, Reference Count was zero before increment\n",
+				      object));
+		}
 
 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
-				  "Obj %p Refs=%X, [Incremented]\n",
-				  object, new_count));
+				  "Obj %p Type %.2X Refs %.2X [Incremented]\n",
+				  object, object->common.type, new_count));
 		break;
 
 	case REF_DECREMENT:
 
-		if (count < 1) {
-			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
-					  "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
-					  object, new_count));
-
-			new_count = 0;
-		} else {
-			new_count--;
+		/* The current reference count must be non-zero */
 
-			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
-					  "Obj %p Refs=%X, [Decremented]\n",
-					  object, new_count));
+		if (original_count) {
+			new_count = original_count - 1;
+			object->common.reference_count = new_count;
 		}
 
-		if (object->common.type == ACPI_TYPE_METHOD) {
-			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
-					  "Method Obj %p Refs=%X, [Decremented]\n",
-					  object, new_count));
-		}
+		acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
 
-		object->common.reference_count = new_count;
-		if (new_count == 0) {
-			acpi_ut_delete_internal_obj(object);
+		if (!original_count) {
+			ACPI_WARNING((AE_INFO,
+				      "Obj %p, Reference Count is already zero, cannot decrement\n",
+				      object));
 		}
-		break;
-
-	case REF_FORCE_DELETE:
 
 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
-				  "Obj %p Refs=%X, Force delete! (Set to 0)\n",
-				  object, count));
+				  "Obj %p Type %.2X Refs %.2X [Decremented]\n",
+				  object, object->common.type, new_count));
 
-		new_count = 0;
-		object->common.reference_count = new_count;
-		acpi_ut_delete_internal_obj(object);
+		/* Actually delete the object on a reference count of zero */
+
+		if (new_count == 0) {
+			acpi_ut_delete_internal_obj(object);
+		}
 		break;
 
 	default:
 
-		ACPI_ERROR((AE_INFO, "Unknown action (0x%X)", action));
-		break;
+		acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
+		ACPI_ERROR((AE_INFO, "Unknown Reference Count action (0x%X)",
+			    action));
+		return;
 	}
 
 	/*
 	 * Sanity check the reference count, for debug purposes only.
 	 * (A deleted object will have a huge reference count)
 	 */
-	if (count > ACPI_MAX_REFERENCE_COUNT) {
+	if (new_count > ACPI_MAX_REFERENCE_COUNT) {
 		ACPI_WARNING((AE_INFO,
-			      "Large Reference Count (0x%X) in object %p",
-			      count, object));
+			      "Large Reference Count (0x%X) in object %p, Type=0x%.2X",
+			      new_count, object, object->common.type));
 	}
 }
 
@@ -458,8 +474,7 @@ acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
  *
  * PARAMETERS:  object              - Increment ref count for this object
  *                                    and all sub-objects
- *              action              - Either REF_INCREMENT or REF_DECREMENT or
- *                                    REF_FORCE_DELETE
+ *              action              - Either REF_INCREMENT or REF_DECREMENT
  *
  * RETURN:      Status
  *
@@ -484,7 +499,7 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 	union acpi_generic_state *state;
 	u32 i;
 
-	ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
+	ACPI_FUNCTION_NAME(ut_update_object_reference);
 
 	while (object) {
 
@@ -493,7 +508,7 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 		if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 					  "Object %p is NS handle\n", object));
-			return_ACPI_STATUS(AE_OK);
+			return (AE_OK);
 		}
 
 		/*
@@ -505,7 +520,6 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 		case ACPI_TYPE_PROCESSOR:
 		case ACPI_TYPE_POWER:
 		case ACPI_TYPE_THERMAL:
-
 			/*
 			 * Update the notify objects for these types (if present)
 			 * Two lists, system and device notify handlers.
@@ -530,18 +544,42 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 			 */
 			for (i = 0; i < object->package.count; i++) {
 				/*
-				 * Push each element onto the stack for later processing.
-				 * Note: There can be null elements within the package,
-				 * these are simply ignored
+				 * Null package elements are legal and can be simply
+				 * ignored.
 				 */
-				status =
-				    acpi_ut_create_update_state_and_push
-				    (object->package.elements[i], action,
-				     &state_list);
-				if (ACPI_FAILURE(status)) {
-					goto error_exit;
+				next_object = object->package.elements[i];
+				if (!next_object) {
+					continue;
+				}
+
+				switch (next_object->common.type) {
+				case ACPI_TYPE_INTEGER:
+				case ACPI_TYPE_STRING:
+				case ACPI_TYPE_BUFFER:
+					/*
+					 * For these very simple sub-objects, we can just
+					 * update the reference count here and continue.
+					 * Greatly increases performance of this operation.
+					 */
+					acpi_ut_update_ref_count(next_object,
+								 action);
+					break;
+
+				default:
+					/*
+					 * For complex sub-objects, push them onto the stack
+					 * for later processing (this eliminates recursion.)
+					 */
+					status =
+					    acpi_ut_create_update_state_and_push
+					    (next_object, action, &state_list);
+					if (ACPI_FAILURE(status)) {
+						goto error_exit;
+					}
+					break;
 				}
 			}
+			next_object = NULL;
 			break;
 
 		case ACPI_TYPE_BUFFER_FIELD:
@@ -596,6 +634,7 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 
 		case ACPI_TYPE_REGION:
 		default:
+
 			break;	/* No subobjects for all other types */
 		}
 
@@ -619,9 +658,9 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 		}
 	}
 
-	return_ACPI_STATUS(AE_OK);
+	return (AE_OK);
 
-      error_exit:
+error_exit:
 
 	ACPI_EXCEPTION((AE_INFO, status,
 			"Could not update object reference count"));
@@ -633,7 +672,7 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 		acpi_ut_delete_generic_state(state);
 	}
 
-	return_ACPI_STATUS(status);
+	return (status);
 }
 
 /*******************************************************************************
@@ -652,12 +691,12 @@ acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 void acpi_ut_add_reference(union acpi_operand_object *object)
 {
 
-	ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
+	ACPI_FUNCTION_NAME(ut_add_reference);
 
 	/* Ensure that we have a valid object */
 
 	if (!acpi_ut_valid_internal_object(object)) {
-		return_VOID;
+		return;
 	}
 
 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
@@ -667,7 +706,7 @@ void acpi_ut_add_reference(union acpi_operand_object *object)
 	/* Increment the reference count */
 
 	(void)acpi_ut_update_object_reference(object, REF_INCREMENT);
-	return_VOID;
+	return;
 }
 
 /*******************************************************************************
@@ -685,22 +724,21 @@ void acpi_ut_add_reference(union acpi_operand_object *object)
 void acpi_ut_remove_reference(union acpi_operand_object *object)
 {
 
-	ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
+	ACPI_FUNCTION_NAME(ut_remove_reference);
 
 	/*
 	 * Allow a NULL pointer to be passed in, just ignore it. This saves
 	 * each caller from having to check. Also, ignore NS nodes.
-	 *
 	 */
 	if (!object ||
 	    (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
-		return_VOID;
+		return;
 	}
 
 	/* Ensure that we have a valid object */
 
 	if (!acpi_ut_valid_internal_object(object)) {
-		return_VOID;
+		return;
 	}
 
 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
@@ -713,5 +751,5 @@ void acpi_ut_remove_reference(union acpi_operand_object *object)
 	 * of all subobjects!)
 	 */
 	(void)acpi_ut_update_object_reference(object, REF_DECREMENT);
-	return_VOID;
+	return;
 }