/****************************************************************************** * * Module Name: dsmethod - Parser/Interpreter interface - control method parsing * *****************************************************************************/ /* * Copyright (C) 2000 - 2007, R. Byron Moore * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer, * without modification. * 2. Redistributions in binary form must reproduce at minimum a disclaimer * substantially similar to the "NO WARRANTY" disclaimer below * ("Disclaimer") and any redistribution must be conditioned upon * including a substantially similar Disclaimer requirement for further * binary redistribution. * 3. Neither the names of the above-listed copyright holders nor the names * of any contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * NO WARRANTY * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGES. */ #include <acpi/acpi.h> #include <acpi/acparser.h> #include <acpi/amlcode.h> #include <acpi/acdispat.h> #include <acpi/acinterp.h> #include <acpi/acnamesp.h> #include <acpi/acdisasm.h> #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 * * PARAMETERS: Status - Execution status * walk_state - Current state * * RETURN: Status * * DESCRIPTION: Called on method error. Invoke the global exception handler if * present, dump the method data if the disassembler is configured * * 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) { ACPI_FUNCTION_ENTRY(); /* Ignore AE_OK and control exception codes */ if (ACPI_SUCCESS(status) || (status & AE_CODE_CONTROL)) { return (status); } /* Invoke the global exception handler */ if (acpi_gbl_exception_handler) { /* Exit the interpreter, allow handler to execute methods */ acpi_ex_exit_interpreter(); /* * Handler can map the exception code to anything it wants, including * AE_OK, in which case the executing method will not be aborted. */ status = acpi_gbl_exception_handler(status, walk_state->method_node ? walk_state->method_node-> name.integer : 0, walk_state->opcode, walk_state->aml_offset, NULL); (void)acpi_ex_enter_interpreter(); } #ifdef ACPI_DISASSEMBLER if (ACPI_FAILURE(status)) { /* Display method locals/args if disassembler is present */ acpi_dm_dump_method_info(status, walk_state, walk_state->op); } #endif return (status); } /******************************************************************************* * * 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_TRACE(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 * walk_state - current state, NULL if not yet executing * a method. * * RETURN: Status * * DESCRIPTION: Prepare a method for execution. Parses the method if necessary, * increments the thread count, and waits at the method semaphore * for clearance to execute. * ******************************************************************************/ acpi_status 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; ACPI_FUNCTION_TRACE_PTR(ds_begin_method_execution, method_node); if (!method_node) { return_ACPI_STATUS(AE_NULL_ENTRY); } /* Prevent wraparound of thread count */ if (obj_desc->method.thread_count == ACPI_UINT8_MAX) { ACPI_ERROR((AE_INFO, "Method reached maximum reentrancy limit (255)")); return_ACPI_STATUS(AE_AML_METHOD_LIMIT); } /* * If this method is serialized, we need to acquire the method mutex. */ if (obj_desc->method.method_flags & AML_METHOD_SERIALIZED) { /* * 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 (!obj_desc->method.mutex) { status = acpi_ds_create_method_mutex(obj_desc); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } } /* * 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 */ 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 (acpi_os_get_thread_id() != obj_desc->method.mutex->mutex.owner_thread_id) { /* * 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 */ obj_desc->method.mutex->mutex.owner_thread_id = acpi_os_get_thread_id(); if (walk_state) { obj_desc->method.mutex->mutex. original_sync_level = walk_state->thread->current_sync_level; 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++; } /* * 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)) { goto cleanup; } } /* * Increment the method parse tree thread count since it has been * reentered one more time (even if it is the same thread) */ obj_desc->method.thread_count++; return_ACPI_STATUS(status); cleanup: /* On error, must release the method mutex (if present) */ if (obj_desc->method.mutex) { acpi_os_release_mutex(obj_desc->method.mutex->mutex.os_mutex); } return_ACPI_STATUS(status); } /******************************************************************************* * * FUNCTION: acpi_ds_call_control_method * * PARAMETERS: Thread - Info for this thread * this_walk_state - Current walk state * Op - Current Op to be walked * * RETURN: Status * * DESCRIPTION: Transfer execution to a called control method * ******************************************************************************/ acpi_status acpi_ds_call_control_method(struct acpi_thread_state *thread, struct acpi_walk_state *this_walk_state, union acpi_parse_object *op) { acpi_status status; struct acpi_namespace_node *method_node; struct acpi_walk_state *next_walk_state = NULL; union acpi_operand_object *obj_desc; struct acpi_evaluate_info *info; u32 i; ACPI_FUNCTION_TRACE_PTR(ds_call_control_method, this_walk_state); ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Calling method %p, currentstate=%p\n", this_walk_state->prev_op, this_walk_state)); /* * Get the namespace entry for the control method we are about to call */ method_node = this_walk_state->method_call_node; if (!method_node) { return_ACPI_STATUS(AE_NULL_ENTRY); } obj_desc = acpi_ns_get_attached_object(method_node); if (!obj_desc) { return_ACPI_STATUS(AE_NULL_OBJECT); } /* Init for new method, possibly wait on method mutex */ status = acpi_ds_begin_method_execution(method_node, obj_desc, this_walk_state); if (ACPI_FAILURE(status)) { return_ACPI_STATUS(status); } /* Begin method parse/execution. Create a new walk state */ next_walk_state = acpi_ds_create_walk_state(obj_desc->method.owner_id, NULL, obj_desc, thread); if (!next_walk_state) { status = AE_NO_MEMORY; goto cleanup; } /* * 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. Also, null terminate the list of arguments */ this_walk_state->operands[this_walk_state->num_operands] = NULL; /* * Allocate and initialize the evaluation information block * TBD: this is somewhat inefficient, should change interface to * ds_init_aml_walk. For now, keeps this struct off the CPU stack */ info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info)); if (!info) { return_ACPI_STATUS(AE_NO_MEMORY); } info->parameters = &this_walk_state->operands[0]; info->parameter_type = ACPI_PARAM_ARGS; status = acpi_ds_init_aml_walk(next_walk_state, NULL, method_node, obj_desc->method.aml_start, obj_desc->method.aml_length, info, ACPI_IMODE_EXECUTE); ACPI_FREE(info); if (ACPI_FAILURE(status)) { goto cleanup; } /* * Delete the operands on the previous walkstate operand stack * (they were copied to new objects) */ for (i = 0; i < obj_desc->method.param_count; i++) { acpi_ut_remove_reference(this_walk_state->operands[i]); this_walk_state->operands[i] = NULL; } /* Clear the operand stack */ this_walk_state->num_operands = 0; ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "**** Begin nested execution of [%4.4s] **** WalkState=%p\n", method_node->name.ascii, next_walk_state)); /* Invoke an internal method if necessary */ if (obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY) { status = obj_desc->method.implementation(next_walk_state); } return_ACPI_STATUS(status); cleanup: /* On error, we must terminate the method properly */ acpi_ds_terminate_control_method(obj_desc, next_walk_state); if (next_walk_state) { acpi_ds_delete_walk_state(next_walk_state); } return_ACPI_STATUS(status); } /******************************************************************************* * * FUNCTION: acpi_ds_restart_control_method * * PARAMETERS: walk_state - State for preempted method (caller) * return_desc - Return value from the called method * * RETURN: Status * * DESCRIPTION: Restart a method that was preempted by another (nested) method * invocation. Handle the return value (if any) from the callee. * ******************************************************************************/ acpi_status acpi_ds_restart_control_method(struct acpi_walk_state *walk_state, union acpi_operand_object *return_desc) { acpi_status status; int same_as_implicit_return; ACPI_FUNCTION_TRACE_PTR(ds_restart_control_method, walk_state); ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "****Restart [%4.4s] Op %p ReturnValueFromCallee %p\n", acpi_ut_get_node_name(walk_state->method_node), walk_state->method_call_op, return_desc)); ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, " ReturnFromThisMethodUsed?=%X ResStack %p Walk %p\n", walk_state->return_used, walk_state->results, walk_state)); /* Did the called method return a value? */ if (return_desc) { /* Is the implicit return object the same as the return desc? */ same_as_implicit_return = (walk_state->implicit_return_obj == return_desc); /* Are we actually going to use the return value? */ if (walk_state->return_used) { /* Save the return value from the previous method */ status = acpi_ds_result_push(return_desc, walk_state); if (ACPI_FAILURE(status)) { acpi_ut_remove_reference(return_desc); return_ACPI_STATUS(status); } /* * Save as THIS method's return value in case it is returned * immediately to yet another method */ walk_state->return_desc = return_desc; } /* * The following code is the optional support for the so-called * "implicit return". Some AML code assumes that the last value of the * method is "implicitly" returned to the caller, in the absence of an * explicit return value. * * Just save the last result of the method as the return value. * * NOTE: this is optional because the ASL language does not actually * support this behavior. */ else if (!acpi_ds_do_implicit_return (return_desc, walk_state, FALSE) || same_as_implicit_return) { /* * Delete the return value if it will not be used by the * calling method or remove one reference if the explicit return * is the same as the implicit return value. */ acpi_ut_remove_reference(return_desc); } } return_ACPI_STATUS(AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_terminate_control_method * * PARAMETERS: method_desc - Method object * walk_state - State associated with the method * * RETURN: None * * DESCRIPTION: Terminate a control method. Delete everything that the method * created, delete all locals and arguments, and delete the parse * tree if requested. * * MUTEX: Interpreter is locked * ******************************************************************************/ void acpi_ds_terminate_control_method(union acpi_operand_object *method_desc, struct acpi_walk_state *walk_state) { struct acpi_namespace_node *method_node; acpi_status status; ACPI_FUNCTION_TRACE_PTR(ds_terminate_control_method, walk_state); /* method_desc is required, walk_state is optional */ if (!method_desc) { return_VOID; } if (walk_state) { /* Delete all arguments and locals */ acpi_ds_method_data_delete_all(walk_state); } /* * If method is serialized, release the mutex and restore the * current sync level for this thread */ if (method_desc->method.mutex) { /* Acquisition Depth handles recursive calls */ 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; acpi_os_release_mutex(method_desc->method.mutex->mutex. os_mutex); method_desc->method.mutex->mutex.owner_thread_id = ACPI_MUTEX_NOT_ACQUIRED; } } if (walk_state) { /* * Delete any objects created by this method during execution. * The method Node is stored in the walk state */ method_node = walk_state->method_node; /* * Delete any namespace objects created anywhere within * the namespace by the execution of this method */ acpi_ns_delete_namespace_by_owner(method_desc->method.owner_id); } /* Decrement the thread count on the method */ if (method_desc->method.thread_count) { method_desc->method.thread_count--; } else { ACPI_ERROR((AE_INFO, "Invalid zero thread count in method")); } /* Are there any other threads currently executing this method? */ if (method_desc->method.thread_count) { /* * Additional threads. Do not release the owner_id in this case, * we immediately reuse it for the next thread executing this method */ ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "*** Completed execution of one thread, %d threads remaining\n", method_desc->method.thread_count)); } else { /* This is the only executing thread for this method */ /* * 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 * 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.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 */ acpi_ut_release_owner_id(&method_desc->method.owner_id); } return_VOID; }