/****************************************************************************** * * Module Name: dsmethod - Parser/Interpreter interface - control method parsing * *****************************************************************************/ /* * Copyright (C) 2000 - 2005, 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 #include #include #include #include #include #define _COMPONENT ACPI_DISPATCHER ACPI_MODULE_NAME("dsmethod") /******************************************************************************* * * 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) * * 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_namespace_node *calling_method_node) { 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_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. */ if (obj_desc->method.semaphore) { /* * 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. */ if (method_node == calling_method_node) { if (obj_desc->method.thread_count >= obj_desc->method.concurrency) { return_ACPI_STATUS(AE_AML_METHOD_LIMIT); } } /* * Get a unit from the method semaphore. This releases the * interpreter if we block */ status = acpi_ex_system_wait_semaphore(obj_desc->method.semaphore, 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) */ obj_desc->method.thread_count++; 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_parameter_info info; u32 i; ACPI_FUNCTION_TRACE_PTR("ds_call_control_method", this_walk_state); ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Execute 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, wait on concurrency semaphore */ status = acpi_ds_begin_method_execution(method_node, obj_desc, this_walk_state->method_node); if (ACPI_FAILURE(status)) { goto cleanup; } if (!(obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY)) { /* 1) Parse: Create a new walk state for the preempting walk */ next_walk_state = acpi_ds_create_walk_state(obj_desc->method.owner_id, op, obj_desc, NULL); if (!next_walk_state) { return_ACPI_STATUS(AE_NO_MEMORY); } /* Create and init a Root Node */ op = acpi_ps_create_scope_op(); if (!op) { status = AE_NO_MEMORY; goto cleanup; } status = acpi_ds_init_aml_walk(next_walk_state, op, method_node, obj_desc->method.aml_start, obj_desc->method.aml_length, NULL, 1); if (ACPI_FAILURE(status)) { acpi_ds_delete_walk_state(next_walk_state); goto cleanup; } /* Begin AML parse */ status = acpi_ps_parse_aml(next_walk_state); acpi_ps_delete_parse_tree(op); } /* 2) Execute: Create a new state for the preempting walk */ 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; 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, 3); 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, "Starting nested execution, newstate=%p\n", next_walk_state)); if (obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY) { status = obj_desc->method.implementation(next_walk_state); } return_ACPI_STATUS(status); cleanup: /* 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--; } /* 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); } /******************************************************************************* * * 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; ACPI_FUNCTION_TRACE_PTR("ds_restart_control_method", walk_state); ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "****Restart [%4.4s] Op %p return_value_from_callee %p\n", (char *)&walk_state->method_node->name, walk_state->method_call_op, return_desc)); ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, " return_from_this_method_used?=%X res_stack %p Walk %p\n", walk_state->return_used, walk_state->results, walk_state)); /* Did the called method return a value? */ if (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 a so-called "implicit return". Some AML code * assumes that the last value of the method is "implicitly" returned * to the caller. Just save the last result 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)) { /* * Delete the return value if it will not be used by the * calling method */ acpi_ut_remove_reference(return_desc); } } return_ACPI_STATUS(AE_OK); } /******************************************************************************* * * FUNCTION: acpi_ds_terminate_control_method * * PARAMETERS: walk_state - State of 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. * ******************************************************************************/ void acpi_ds_terminate_control_method(struct acpi_walk_state *walk_state) { union acpi_operand_object *obj_desc; struct acpi_namespace_node *method_node; acpi_status status; ACPI_FUNCTION_TRACE_PTR("ds_terminate_control_method", walk_state); if (!walk_state) { return_VOID; } /* The current method object was saved in the walk state */ obj_desc = walk_state->method_desc; if (!obj_desc) { return_VOID; } /* Delete all arguments and locals */ acpi_ds_method_data_delete_all(walk_state); /* * Lock the parser while we terminate this method. * If this is the last thread executing the method, * we have additional cleanup to perform */ status = acpi_ut_acquire_mutex(ACPI_MTX_PARSER); if (ACPI_FAILURE(status)) { return_VOID; } /* Signal completion of the execution of this method if necessary */ if (walk_state->method_desc->method.semaphore) { status = acpi_os_signal_semaphore(walk_state->method_desc->method. semaphore, 1); if (ACPI_FAILURE(status)) { ACPI_REPORT_ERROR(("Could not signal method semaphore\n")); /* Ignore error and continue cleanup */ } } /* * There are no more threads executing this method. Perform * additional cleanup. * * The method Node is stored in the walk state */ method_node = walk_state->method_node; /* Lock namespace for possible update */ status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE); if (ACPI_FAILURE(status)) { goto exit; } /* * Delete any namespace entries created immediately underneath * the method */ if (method_node->child) { acpi_ns_delete_namespace_subtree(method_node); } /* * Delete any namespace entries created anywhere else within * the namespace by the execution of this method */ acpi_ns_delete_namespace_by_owner(walk_state->method_desc->method. owner_id); status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE); /* Are there any other threads currently executing this method? */ if (walk_state->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", walk_state->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 ((walk_state->method_desc->method.concurrency == 1) && (!walk_state->method_desc->method.semaphore)) { status = acpi_os_create_semaphore(1, 1, &walk_state-> method_desc->method. semaphore); } /* No more threads, we can free the owner_id */ acpi_ut_release_owner_id(&walk_state->method_desc->method. owner_id); } exit: (void)acpi_ut_release_mutex(ACPI_MTX_PARSER); 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] **** named_obj=%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 **** named_obj=%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