Merge master.kernel.org:/home/rmk/linux-2.6-arm

[linux-2.6-omap-h63xx.git] / drivers / acpi / dispatcher / dsmethod.c

diff --git a/drivers/acpi/dispatcher/dsmethod.c b/drivers/acpi/dispatcher/dsmethod.c
index 77fcfc3070dbfa14048dd27fdb3af21198d18bea..36c1ca0b9adb71a9b2d19fddd711a4b545a45312 100644 (file)
--- a/drivers/acpi/dispatcher/dsmethod.c
+++ b/drivers/acpi/dispatcher/dsmethod.c
@@ -207,6 +207,13 @@ acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node,
                return_ACPI_STATUS(AE_NULL_ENTRY);
        }
 
+       /* Prevent wraparound of thread count */
+
+       if (obj_desc->method.thread_count == ACPI_UINT8_MAX) {
+               ACPI_REPORT_ERROR(("Method reached maximum reentrancy limit (255)\n"));
+               return_ACPI_STATUS(AE_AML_METHOD_LIMIT);
+       }
+
        /*
         * If there is a concurrency limit on this method, we need to
         * obtain a unit from the method semaphore.
@@ -236,6 +243,18 @@ acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node,
                                                  ACPI_WAIT_FOREVER);
        }
 
+       /*
+        * Allocate an Owner ID for this method, only if this is the first thread
+        * to begin concurrent execution. We only need one owner_id, even if the
+        * method is invoked recursively.
+        */
+       if (!obj_desc->method.owner_id) {
+               status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id);
+               if (ACPI_FAILURE(status)) {
+                       return_ACPI_STATUS(status);
+               }
+       }
+
        /*
         * Increment the method parse tree thread count since it has been
         * reentered one more time (even if it is the same thread)
@@ -289,11 +308,6 @@ acpi_ds_call_control_method(struct acpi_thread_state *thread,
                return_ACPI_STATUS(AE_NULL_OBJECT);
        }
 
-       status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id);
-       if (ACPI_FAILURE(status)) {
-               return_ACPI_STATUS(status);
-       }
-
        /* Init for new method, wait on concurrency semaphore */
 
        status = acpi_ds_begin_method_execution(method_node, obj_desc,
@@ -345,9 +359,8 @@ acpi_ds_call_control_method(struct acpi_thread_state *thread,
        }
        /*
         * The resolved arguments were put on the previous walk state's operand
-        * stack.  Operands on the previous walk state stack always
-        * start at index 0.
-        * Null terminate the list of arguments
+        * stack. Operands on the previous walk state stack always
+        * start at index 0. Also, null terminate the list of arguments
         */
        this_walk_state->operands[this_walk_state->num_operands] = NULL;
 
@@ -380,21 +393,20 @@ acpi_ds_call_control_method(struct acpi_thread_state *thread,
 
        if (obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY) {
                status = obj_desc->method.implementation(next_walk_state);
-               return_ACPI_STATUS(status);
        }
 
-       return_ACPI_STATUS(AE_OK);
-
-       /* On error, we must delete the new walk state */
+       return_ACPI_STATUS(status);
 
       cleanup:
-       acpi_ut_release_owner_id(&obj_desc->method.owner_id);
-       if (next_walk_state && (next_walk_state->method_desc)) {
-               /* Decrement the thread count on the method parse tree */
+       /* Decrement the thread count on the method parse tree */
 
+       if (next_walk_state && (next_walk_state->method_desc)) {
                next_walk_state->method_desc->method.thread_count--;
        }
-       (void)acpi_ds_terminate_control_method(next_walk_state);
+
+       /* On error, we must delete the new walk state */
+
+       acpi_ds_terminate_control_method(next_walk_state);
        acpi_ds_delete_walk_state(next_walk_state);
        return_ACPI_STATUS(status);
 }
@@ -479,7 +491,7 @@ acpi_ds_restart_control_method(struct acpi_walk_state *walk_state,
  *
  * PARAMETERS:  walk_state          - State of the method
  *
- * RETURN:      Status
+ * RETURN:      None
  *
  * DESCRIPTION: Terminate a control method.  Delete everything that the method
  *              created, delete all locals and arguments, and delete the parse
@@ -487,7 +499,7 @@ acpi_ds_restart_control_method(struct acpi_walk_state *walk_state,
  *
  ******************************************************************************/
 
-acpi_status acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
+void acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
 {
        union acpi_operand_object *obj_desc;
        struct acpi_namespace_node *method_node;
@@ -496,14 +508,14 @@ acpi_status acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
        ACPI_FUNCTION_TRACE_PTR("ds_terminate_control_method", walk_state);
 
        if (!walk_state) {
-               return (AE_BAD_PARAMETER);
+               return_VOID;
        }
 
        /* The current method object was saved in the walk state */
 
        obj_desc = walk_state->method_desc;
        if (!obj_desc) {
-               return_ACPI_STATUS(AE_OK);
+               return_VOID;
        }
 
        /* Delete all arguments and locals */
@@ -517,7 +529,7 @@ acpi_status acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
         */
        status = acpi_ut_acquire_mutex(ACPI_MTX_PARSER);
        if (ACPI_FAILURE(status)) {
-               return_ACPI_STATUS(status);
+               return_VOID;
        }
 
        /* Signal completion of the execution of this method if necessary */
@@ -528,7 +540,6 @@ acpi_status acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
                                             semaphore, 1);
                if (ACPI_FAILURE(status)) {
                        ACPI_REPORT_ERROR(("Could not signal method semaphore\n"));
-                       status = AE_OK;
 
                        /* Ignore error and continue cleanup */
                }
@@ -539,9 +550,8 @@ acpi_status acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
                                  "*** Not deleting method namespace, there are still %d threads\n",
                                  walk_state->method_desc->method.
                                  thread_count));
-       }
+       } else {                /* This is the last executing thread */
 
-       if (!walk_state->method_desc->method.thread_count) {
                /*
                 * Support to dynamically change a method from not_serialized to
                 * Serialized if it appears that the method is written foolishly and
@@ -574,7 +584,7 @@ acpi_status acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
                 */
                status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
                if (ACPI_FAILURE(status)) {
-                       return_ACPI_STATUS(status);
+                       goto exit;
                }
 
                if (method_node->child) {
@@ -590,12 +600,9 @@ acpi_status acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state)
                status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
                acpi_ut_release_owner_id(&walk_state->method_desc->method.
                                         owner_id);
-
-               if (ACPI_FAILURE(status)) {
-                       return_ACPI_STATUS(status);
-               }
        }
 
-       status = acpi_ut_release_mutex(ACPI_MTX_PARSER);
-       return_ACPI_STATUS(status);
+      exit:
+       (void)acpi_ut_release_mutex(ACPI_MTX_PARSER);
+       return_VOID;
 }