1 files changed, 151 insertions, 5 deletions

diff --git a/drivers/acpi/acpica/dsmethod.c b/drivers/acpi/acpica/dsmethod.c
index 2c6d42c2bc01..3c7f7378b94d 100644
--- a/drivers/acpi/acpica/dsmethod.c
+++ b/drivers/acpi/acpica/dsmethod.c
@@ -49,16 +49,155 @@
 #ifdef  ACPI_DISASSEMBLER
 #include "acdisasm.h"
 #endif
+#include "acparser.h"
+#include "amlcode.h"
 
 #define _COMPONENT          ACPI_DISPATCHER
 ACPI_MODULE_NAME("dsmethod")
 
 /* Local prototypes */
 static acpi_status
+acpi_ds_detect_named_opcodes(struct acpi_walk_state *walk_state,
+                             union acpi_parse_object **out_op);
+
+static acpi_status
 acpi_ds_create_method_mutex(union acpi_operand_object *method_desc);
 
 /*******************************************************************************
  *
+ * FUNCTION:    acpi_ds_auto_serialize_method
+ *
+ * PARAMETERS:  node                        - Namespace Node of the method
+ *              obj_desc                    - Method object attached to node
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Parse a control method AML to scan for control methods that
+ *              need serialization due to the creation of named objects.
+ *
+ * NOTE: It is a bit of overkill to mark all such methods serialized, since
+ * there is only a problem if the method actually blocks during execution.
+ * A blocking operation is, for example, a Sleep() operation, or any access
+ * to an operation region. However, it is probably not possible to easily
+ * detect whether a method will block or not, so we simply mark all suspicious
+ * methods as serialized.
+ *
+ * NOTE2: This code is essentially a generic routine for parsing a single
+ * control method.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ds_auto_serialize_method(struct acpi_namespace_node *node,
+                              union acpi_operand_object *obj_desc)
+{
+        acpi_status status;
+        union acpi_parse_object *op = NULL;
+        struct acpi_walk_state *walk_state;
+
+        ACPI_FUNCTION_TRACE_PTR(ds_auto_serialize_method, node);
+
+        ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
+                          "Method auto-serialization parse [%4.4s] %p\n",
+                          acpi_ut_get_node_name(node), node));
+
+        /* Create/Init a root op for the method parse tree */
+
+        op = acpi_ps_alloc_op(AML_METHOD_OP);
+        if (!op) {
+                return_ACPI_STATUS(AE_NO_MEMORY);
+        }
+
+        acpi_ps_set_name(op, node->name.integer);
+        op->common.node = node;
+
+        /* Create and initialize a new walk state */
+
+        walk_state =
+            acpi_ds_create_walk_state(node->owner_id, NULL, NULL, NULL);
+        if (!walk_state) {
+                return_ACPI_STATUS(AE_NO_MEMORY);
+        }
+
+        status =
+            acpi_ds_init_aml_walk(walk_state, op, node,
+                                  obj_desc->method.aml_start,
+                                  obj_desc->method.aml_length, NULL, 0);
+        if (ACPI_FAILURE(status)) {
+                acpi_ds_delete_walk_state(walk_state);
+                return_ACPI_STATUS(status);
+        }
+
+        walk_state->descending_callback = acpi_ds_detect_named_opcodes;
+
+        /* Parse the method, scan for creation of named objects */
+
+        status = acpi_ps_parse_aml(walk_state);
+        if (ACPI_FAILURE(status)) {
+                return_ACPI_STATUS(status);
+        }
+
+        acpi_ps_delete_parse_tree(op);
+        return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_detect_named_opcodes
+ *
+ * PARAMETERS:  walk_state      - Current state of the parse tree walk
+ *              out_op          - Unused, required for parser interface
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Descending callback used during the loading of ACPI tables.
+ *              Currently used to detect methods that must be marked serialized
+ *              in order to avoid problems with the creation of named objects.
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ds_detect_named_opcodes(struct acpi_walk_state *walk_state,
+                             union acpi_parse_object **out_op)
+{
+
+        ACPI_FUNCTION_NAME(acpi_ds_detect_named_opcodes);
+
+        /* We are only interested in opcodes that create a new name */
+
+        if (!
+            (walk_state->op_info->
+             flags & (AML_NAMED | AML_CREATE | AML_FIELD))) {
+                return (AE_OK);
+        }
+
+        /*
+         * At this point, we know we have a Named object opcode.
+         * Mark the method as serialized. Later code will create a mutex for
+         * this method to enforce serialization.
+         *
+         * Note, ACPI_METHOD_IGNORE_SYNC_LEVEL flag means that we will ignore the
+         * Sync Level mechanism for this method, even though it is now serialized.
+         * Otherwise, there can be conflicts with existing ASL code that actually
+         * uses sync levels.
+         */
+        walk_state->method_desc->method.sync_level = 0;
+        walk_state->method_desc->method.info_flags |=
+            (ACPI_METHOD_SERIALIZED | ACPI_METHOD_IGNORE_SYNC_LEVEL);
+
+        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                          "Method serialized [%4.4s] %p - [%s] (%4.4X)\n",
+                          walk_state->method_node->name.ascii,
+                          walk_state->method_node, walk_state->op_info->name,
+                          walk_state->opcode));
+
+        /* Abort the parse, no need to examine this method any further */
+
+        return (AE_CTRL_TERMINATE);
+}
+
+/*******************************************************************************
+ *
  * FUNCTION:    acpi_ds_method_error
  *
  * PARAMETERS:  status          - Execution status
@@ -74,7 +213,7 @@ acpi_ds_create_method_mutex(union acpi_operand_object *method_desc);
  ******************************************************************************/
 
 acpi_status
-acpi_ds_method_error(acpi_status status, struct acpi_walk_state *walk_state)
+acpi_ds_method_error(acpi_status status, struct acpi_walk_state * walk_state)
 {
         ACPI_FUNCTION_ENTRY();
 
@@ -217,13 +356,19 @@ acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node,
                 /*
                  * 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
+                 * deadlock prevention.
+                 *
+                 * If the method was auto-serialized, we just ignore the sync level
+                 * mechanism, because auto-serialization of methods can interfere
+                 * with ASL code that actually uses sync levels.
                  *
                  * Top-level method invocation has no walk state at this point
                  */
                 if (walk_state &&
-                    (walk_state->thread->current_sync_level >
-                     obj_desc->method.mutex->mutex.sync_level)) {
+                    (!(obj_desc->method.
+                       info_flags & ACPI_METHOD_IGNORE_SYNC_LEVEL))
+                    && (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 (%u)",
                                     acpi_ut_get_node_name(method_node),
@@ -668,7 +813,8 @@ acpi_ds_terminate_control_method(union acpi_operand_object *method_desc,
                         method_desc->method.info_flags &=
                             ~ACPI_METHOD_SERIALIZED_PENDING;
                         method_desc->method.info_flags |=
-                            ACPI_METHOD_SERIALIZED;
+                            (ACPI_METHOD_SERIALIZED |
+                             ACPI_METHOD_IGNORE_SYNC_LEVEL);
                         method_desc->method.sync_level = 0;
                 }