/****************************************************************************** * * Module Name: psparse - Parser top level AML parse routines * $Revision: 1.1.1.1 $ * *****************************************************************************/ /* * Copyright (C) 2000, 2001 R. Byron Moore * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* * Parse the AML and build an operation tree as most interpreters, * like Perl, do. Parsing is done by hand rather than with a YACC * generated parser to tightly constrain stack and dynamic memory * usage. At the same time, parsing is kept flexible and the code * fairly compact by parsing based on a list of AML opcode * templates in Aml_op_info[] */ #include "acpi.h" #include "acparser.h" #include "acdispat.h" #include "amlcode.h" #include "acnamesp.h" #include "acdebug.h" #include "acinterp.h" #define _COMPONENT ACPI_PARSER MODULE_NAME ("psparse") u32 acpi_gbl_depth = 0; extern u32 acpi_gbl_scope_depth; /******************************************************************************* * * FUNCTION: Acpi_ps_get_opcode_size * * PARAMETERS: Opcode - An AML opcode * * RETURN: Size of the opcode, in bytes (1 or 2) * * DESCRIPTION: Get the size of the current opcode. * ******************************************************************************/ static u32 acpi_ps_get_opcode_size ( u32 opcode) { /* Extended (2-byte) opcode if > 255 */ if (opcode > 0x00FF) { return (2); } /* Otherwise, just a single byte opcode */ return (1); } /******************************************************************************* * * FUNCTION: Acpi_ps_peek_opcode * * PARAMETERS: Parser_state - A parser state object * * RETURN: Status * * DESCRIPTION: Get next AML opcode (without incrementing AML pointer) * ******************************************************************************/ u16 acpi_ps_peek_opcode ( acpi_parse_state *parser_state) { u8 *aml; u16 opcode; aml = parser_state->aml; opcode = (u16) GET8 (aml); aml++; /* * Original code special cased LNOTEQUAL, LLESSEQUAL, LGREATEREQUAL. * These opcodes are no longer recognized. Instead, they are broken into * two opcodes. * * * if (Opcode == AML_EXTOP * || (Opcode == AML_LNOT * && (GET8 (Aml) == AML_LEQUAL * || GET8 (Aml) == AML_LGREATER * || GET8 (Aml) == AML_LLESS))) * * extended Opcode, !=, <=, or >= */ if (opcode == AML_EXTOP) { /* Extended opcode */ opcode = (u16) ((opcode << 8) | GET8 (aml)); } return (opcode); } /******************************************************************************* * * FUNCTION: Acpi_ps_find_object * * PARAMETERS: Opcode - Current opcode * Parser_state - Current state * Walk_state - Current state * *Op - Where found/new op is returned * * RETURN: Status * * DESCRIPTION: Find a named object. Two versions - one to search the parse * tree (for parser-only applications such as acpidump), another * to search the ACPI internal namespace (the parse tree may no * longer exist) * ******************************************************************************/ #ifdef PARSER_ONLY acpi_status acpi_ps_find_object ( acpi_walk_state *walk_state, acpi_parse_object **out_op) { NATIVE_CHAR *path; /* We are only interested in opcodes that have an associated name */ if (!(walk_state->op_info->flags & AML_NAMED)) { *out_op = walk_state->op; return (AE_OK); } /* Find the name in the parse tree */ path = acpi_ps_get_next_namestring (&walk_state->parser_state); *out_op = acpi_ps_find (acpi_ps_get_parent_scope (&walk_state->parser_state), path, walk_state->opcode, 1); if (!(*out_op)) { return (AE_NOT_FOUND); } return (AE_OK); } #endif /******************************************************************************* * * FUNCTION: Acpi_ps_complete_this_op * * PARAMETERS: Walk_state - Current State * Op - Op to complete * * RETURN: TRUE if Op and subtree was deleted * * DESCRIPTION: Perform any cleanup at the completion of an Op. * ******************************************************************************/ static u8 acpi_ps_complete_this_op ( acpi_walk_state *walk_state, acpi_parse_object *op) { #ifndef PARSER_ONLY acpi_parse_object *prev; acpi_parse_object *next; const acpi_opcode_info *parent_info; acpi_parse_object *replacement_op = NULL; FUNCTION_TRACE_PTR ("Ps_complete_this_op", op); /* Delete this op and the subtree below it if asked to */ if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) == ACPI_PARSE_DELETE_TREE) && (walk_state->op_info->class != AML_CLASS_ARGUMENT)) { /* Make sure that we only delete this subtree */ if (op->parent) { /* * Check if we need to replace the operator and its subtree * with a return value op (placeholder op) */ parent_info = acpi_ps_get_opcode_info (op->parent->opcode); switch (parent_info->class) { case AML_CLASS_CONTROL: /* IF, ELSE, WHILE only */ break; case AML_CLASS_NAMED_OBJECT: /* Scope, method, etc. */ case AML_CLASS_CREATE: /* * These opcodes contain Term_arg operands. The current * op must be replace by a placeholder return op */ if ((op->parent->opcode == AML_REGION_OP) || (op->parent->opcode == AML_CREATE_FIELD_OP) || (op->parent->opcode == AML_CREATE_BIT_FIELD_OP) || (op->parent->opcode == AML_CREATE_BYTE_FIELD_OP) || (op->parent->opcode == AML_CREATE_WORD_FIELD_OP) || (op->parent->opcode == AML_CREATE_DWORD_FIELD_OP) || (op->parent->opcode == AML_CREATE_QWORD_FIELD_OP)) { replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP); if (!replacement_op) { return_VALUE (FALSE); } } break; default: replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP); if (!replacement_op) { return_VALUE (FALSE); } } /* We must unlink this op from the parent tree */ prev = op->parent->value.arg; if (prev == op) { /* This op is the first in the list */ if (replacement_op) { replacement_op->parent = op->parent; replacement_op->value.arg = NULL; op->parent->value.arg = replacement_op; replacement_op->next = op->next; } else { op->parent->value.arg = op->next; } } /* Search the parent list */ else while (prev) { /* Traverse all siblings in the parent's argument list */ next = prev->next; if (next == op) { if (replacement_op) { replacement_op->parent = op->parent; replacement_op->value.arg = NULL; prev->next = replacement_op; replacement_op->next = op->next; next = NULL; } else { prev->next = op->next; next = NULL; } } prev = next; } } /* Now we can actually delete the subtree rooted at op */ acpi_ps_delete_parse_tree (op); return_VALUE (TRUE); } return_VALUE (FALSE); #else return (FALSE); #endif } /******************************************************************************* * * FUNCTION: Acpi_ps_next_parse_state * * PARAMETERS: Parser_state - Current parser state object * * RETURN: * * DESCRIPTION: * ******************************************************************************/ static acpi_status acpi_ps_next_parse_state ( acpi_walk_state *walk_state, acpi_parse_object *op, acpi_status callback_status) { acpi_parse_state *parser_state = &walk_state->parser_state; acpi_status status = AE_CTRL_PENDING; u8 *start; u32 package_length; FUNCTION_TRACE_PTR ("Ps_next_parse_state", op); switch (callback_status) { case AE_CTRL_TERMINATE: /* * A control method was terminated via a RETURN statement. * The walk of this method is complete. */ parser_state->aml = parser_state->aml_end; status = AE_CTRL_TERMINATE; break; case AE_CTRL_PENDING: /* * Predicate of a WHILE was true and the loop just completed an * execution. Go back to the start of the loop and reevaluate the * predicate. */ /* TBD: How to handle a break within a while. */ /* This code attempts it */ parser_state->aml = walk_state->aml_last_while; break; case AE_CTRL_TRUE: /* * Predicate of an IF was true, and we are at the matching ELSE. * Just close out this package * * Note: Parser_state->Aml is modified by the package length procedure * TBD: [Investigate] perhaps it shouldn't, too much trouble */ start = parser_state->aml; package_length = acpi_ps_get_next_package_length (parser_state); parser_state->aml = start + package_length; break; case AE_CTRL_FALSE: /* * Either an IF/WHILE Predicate was false or we encountered a BREAK * opcode. In both cases, we do not execute the rest of the * package; We simply close out the parent (finishing the walk of * this branch of the tree) and continue execution at the parent * level. */ parser_state->aml = parser_state->scope->parse_scope.pkg_end; /* In the case of a BREAK, just force a predicate (if any) to FALSE */ walk_state->control_state->common.value = FALSE; status = AE_CTRL_END; break; case AE_CTRL_TRANSFER: /* * A method call (invocation) -- transfer control */ status = AE_CTRL_TRANSFER; walk_state->prev_op = op; walk_state->method_call_op = op; walk_state->method_call_node = (op->value.arg)->node; /* Will return value (if any) be used by the caller? */ walk_state->return_used = acpi_ds_is_result_used (op, walk_state); break; default: status = callback_status; if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) { status = AE_OK; } break; } return_ACPI_STATUS (status); } /******************************************************************************* * * FUNCTION: Acpi_ps_parse_loop * * PARAMETERS: Parser_state - Current parser state object * * RETURN: Status * * DESCRIPTION: Parse AML (pointed to by the current parser state) and return * a tree of ops. * ******************************************************************************/ acpi_status acpi_ps_parse_loop ( acpi_walk_state *walk_state) { acpi_status status = AE_OK; acpi_parse_object *op = NULL; /* current op */ acpi_parse_object *arg = NULL; acpi_parse_object pre_op; acpi_parse_state *parser_state; u8 *aml_op_start; FUNCTION_TRACE_PTR ("Ps_parse_loop", walk_state); parser_state = &walk_state->parser_state; walk_state->arg_types = 0; #ifndef PARSER_ONLY if (walk_state->walk_type & WALK_METHOD_RESTART) { /* We are restarting a preempted control method */ if (acpi_ps_has_completed_scope (parser_state)) { /* * We must check if a predicate to an IF or WHILE statement * was just completed */ if ((parser_state->scope->parse_scope.op) && ((parser_state->scope->parse_scope.op->opcode == AML_IF_OP) || (parser_state->scope->parse_scope.op->opcode == AML_WHILE_OP)) && (walk_state->control_state) && (walk_state->control_state->common.state == CONTROL_PREDICATE_EXECUTING)) { /* * A predicate was just completed, get the value of the * predicate and branch based on that value */ walk_state->op = NULL; status = acpi_ds_get_predicate_value (walk_state, TRUE); if (ACPI_FAILURE (status) && ((status & AE_CODE_MASK) != AE_CODE_CONTROL)) { if (status == AE_AML_NO_RETURN_VALUE) { ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Invoked method did not return a value, %s\n", acpi_format_exception (status))); } ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Get_predicate Failed, %s\n", acpi_format_exception (status))); return_ACPI_STATUS (status); } status = acpi_ps_next_parse_state (walk_state, op, status); } acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types, &walk_state->arg_count); ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", op)); } else if (walk_state->prev_op) { /* We were in the middle of an op */ op = walk_state->prev_op; walk_state->arg_types = walk_state->prev_arg_types; } } #endif /* * Iterative parsing loop, while there is more aml to process: */ while ((parser_state->aml < parser_state->aml_end) || (op)) { if (!op) { /* Get the next opcode from the AML stream */ aml_op_start = parser_state->aml; walk_state->aml_offset = parser_state->aml - parser_state->aml_start; walk_state->opcode = acpi_ps_peek_opcode (parser_state); /* * First cut to determine what we have found: * 1) A valid AML opcode * 2) A name string * 3) An unknown/invalid opcode */ walk_state->op_info = acpi_ps_get_opcode_info (walk_state->opcode); switch (walk_state->op_info->class) { case AML_CLASS_ASCII: case AML_CLASS_PREFIX: /* * Starts with a valid prefix or ASCII char, this is a name * string. Convert the bare name string to a namepath. */ walk_state->opcode = AML_INT_NAMEPATH_OP; walk_state->arg_types = ARGP_NAMESTRING; break; case AML_CLASS_UNKNOWN: /* The opcode is unrecognized. Just skip unknown opcodes */ ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Found unknown opcode %X at AML offset %X, ignoring\n", walk_state->opcode, walk_state->aml_offset)); DUMP_BUFFER (parser_state->aml, 128); /* Assume one-byte bad opcode */ parser_state->aml++; continue; default: /* Found opcode info, this is a normal opcode */ parser_state->aml += acpi_ps_get_opcode_size (walk_state->opcode); walk_state->arg_types = walk_state->op_info->parse_args; break; } /* Create Op structure and append to parent's argument list */ if (walk_state->op_info->flags & AML_NAMED) { pre_op.value.arg = NULL; pre_op.opcode = walk_state->opcode; while (GET_CURRENT_ARG_TYPE (walk_state->arg_types) != ARGP_NAME) { arg = acpi_ps_get_next_arg (parser_state, GET_CURRENT_ARG_TYPE (walk_state->arg_types), &walk_state->arg_count); acpi_ps_append_arg (&pre_op, arg); INCREMENT_ARG_LIST (walk_state->arg_types); } /* We know that this arg is a name, move to next arg */ INCREMENT_ARG_LIST (walk_state->arg_types); if (walk_state->descending_callback != NULL) { /* * Find the object. This will either insert the object into * the namespace or simply look it up */ walk_state->op = NULL; status = walk_state->descending_callback (walk_state, &op); /* TBD: check status here? */ if (ACPI_FAILURE (status)) { ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "During name lookup/catalog, %s\n", acpi_format_exception (status))); goto close_this_op; } if (op == NULL) { continue; } status = acpi_ps_next_parse_state (walk_state, op, status); if (status == AE_CTRL_PENDING) { status = AE_OK; goto close_this_op; } if (ACPI_FAILURE (status)) { goto close_this_op; } } acpi_ps_append_arg (op, pre_op.value.arg); acpi_gbl_depth++; if (op->opcode == AML_REGION_OP) { /* * Defer final parsing of an Operation_region body, * because we don't have enough info in the first pass * to parse it correctly (i.e., there may be method * calls within the Term_arg elements of the body. * * However, we must continue parsing because * the opregion is not a standalone package -- * we don't know where the end is at this point. * * (Length is unknown until parse of the body complete) */ ((acpi_parse2_object * ) op)->data = aml_op_start; ((acpi_parse2_object * ) op)->length = 0; } } else { /* Not a named opcode, just allocate Op and append to parent */ walk_state->op_info = acpi_ps_get_opcode_info (walk_state->opcode); op = acpi_ps_alloc_op (walk_state->opcode); if (!op) { return_ACPI_STATUS (AE_NO_MEMORY); } if (walk_state->op_info->flags & AML_CREATE) { /* * Backup to beginning of Create_xXXfield declaration * Body_length is unknown until we parse the body */ ((acpi_parse2_object * ) op)->data = aml_op_start; ((acpi_parse2_object * ) op)->length = 0; } acpi_ps_append_arg (acpi_ps_get_parent_scope (parser_state), op); if ((walk_state->descending_callback != NULL)) { /* * Find the object. This will either insert the object into * the namespace or simply look it up */ walk_state->op = op; status = walk_state->descending_callback (walk_state, &op); status = acpi_ps_next_parse_state (walk_state, op, status); if (status == AE_CTRL_PENDING) { status = AE_OK; goto close_this_op; } if (ACPI_FAILURE (status)) { goto close_this_op; } } } op->aml_offset = walk_state->aml_offset; if (walk_state->op_info) { ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Op=%p Opcode=%4.4X Aml %p Oft=%5.5X\n", op, op->opcode, parser_state->aml, op->aml_offset)); } } /* Start Arg_count at zero because we don't know if there are any args yet */ walk_state->arg_count = 0; if (walk_state->arg_types) /* Are there any arguments that must be processed? */ { /* get arguments */ switch (op->opcode) { case AML_BYTE_OP: /* AML_BYTEDATA_ARG */ case AML_WORD_OP: /* AML_WORDDATA_ARG */ case AML_DWORD_OP: /* AML_DWORDATA_ARG */ case AML_QWORD_OP: /* AML_QWORDATA_ARG */ case AML_STRING_OP: /* AML_ASCIICHARLIST_ARG */ /* fill in constant or string argument directly */ acpi_ps_get_next_simple_arg (parser_state, GET_CURRENT_ARG_TYPE (walk_state->arg_types), op); break; case AML_INT_NAMEPATH_OP: /* AML_NAMESTRING_ARG */ acpi_ps_get_next_namepath (parser_state, op, &walk_state->arg_count, 1); walk_state->arg_types = 0; break; default: /* Op is not a constant or string, append each argument */ while (GET_CURRENT_ARG_TYPE (walk_state->arg_types) && !walk_state->arg_count) { walk_state->aml_offset = parser_state->aml - parser_state->aml_start; arg = acpi_ps_get_next_arg (parser_state, GET_CURRENT_ARG_TYPE (walk_state->arg_types), &walk_state->arg_count); if (arg) { arg->aml_offset = walk_state->aml_offset; acpi_ps_append_arg (op, arg); } INCREMENT_ARG_LIST (walk_state->arg_types); } /* For a method, save the length and address of the body */ if (op->opcode == AML_METHOD_OP) { /* * Skip parsing of control method or opregion body, * because we don't have enough info in the first pass * to parse them correctly. */ ((acpi_parse2_object * ) op)->data = parser_state->aml; ((acpi_parse2_object * ) op)->length = (u32) (parser_state->pkg_end - parser_state->aml); /* * Skip body of method. For Op_regions, we must continue * parsing because the opregion is not a standalone * package (We don't know where the end is). */ parser_state->aml = parser_state->pkg_end; walk_state->arg_count = 0; } break; } } /* * Zero Arg_count means that all arguments for this op have been processed */ if (!walk_state->arg_count) { /* completed Op, prepare for next */ walk_state->op_info = acpi_ps_get_opcode_info (op->opcode); if (walk_state->op_info->flags & AML_NAMED) { if (acpi_gbl_depth) { acpi_gbl_depth--; } if (op->opcode == AML_REGION_OP) { /* * Skip parsing of control method or opregion body, * because we don't have enough info in the first pass * to parse them correctly. * * Completed parsing an Op_region declaration, we now * know the length. */ ((acpi_parse2_object * ) op)->length = (u32) (parser_state->aml - ((acpi_parse2_object * ) op)->data); } } if (walk_state->op_info->flags & AML_CREATE) { /* * Backup to beginning of Create_xXXfield declaration (1 for * Opcode) * * Body_length is unknown until we parse the body */ ((acpi_parse2_object * ) op)->length = (u32) (parser_state->aml - ((acpi_parse2_object * ) op)->data); } /* This op complete, notify the dispatcher */ if (walk_state->ascending_callback != NULL) { walk_state->op = op; walk_state->opcode = op->opcode; status = walk_state->ascending_callback (walk_state); status = acpi_ps_next_parse_state (walk_state, op, status); if (status == AE_CTRL_PENDING) { status = AE_OK; goto close_this_op; } } close_this_op: /* * Finished one argument of the containing scope */ parser_state->scope->parse_scope.arg_count--; /* Close this Op (may result in parse subtree deletion) */ if (acpi_ps_complete_this_op (walk_state, op)) { op = NULL; } switch (status) { case AE_OK: break; case AE_CTRL_TRANSFER: /* * We are about to transfer to a called method. */ walk_state->prev_op = op; walk_state->prev_arg_types = walk_state->arg_types; return_ACPI_STATUS (status); break; case AE_CTRL_END: acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types, &walk_state->arg_count); walk_state->op = op; walk_state->op_info = acpi_ps_get_opcode_info (op->opcode); walk_state->opcode = op->opcode; status = walk_state->ascending_callback (walk_state); status = acpi_ps_next_parse_state (walk_state, op, status); acpi_ps_complete_this_op (walk_state, op); op = NULL; status = AE_OK; break; case AE_CTRL_TERMINATE: status = AE_OK; /* Clean up */ do { if (op) { acpi_ps_complete_this_op (walk_state, op); } acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types, &walk_state->arg_count); } while (op); return_ACPI_STATUS (status); break; default: /* All other non-AE_OK status */ if (op == NULL) { acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types, &walk_state->arg_count); } walk_state->prev_op = op; walk_state->prev_arg_types = walk_state->arg_types; /* * TEMP: */ return_ACPI_STATUS (status); break; } /* This scope complete? */ if (acpi_ps_has_completed_scope (parser_state)) { acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types, &walk_state->arg_count); ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", op)); } else { op = NULL; } } /* Arg_count is non-zero */ else { /* complex argument, push Op and prepare for argument */ acpi_ps_push_scope (parser_state, op, walk_state->arg_types, walk_state->arg_count); op = NULL; } } /* while Parser_state->Aml */ /* * Complete the last Op (if not completed), and clear the scope stack. * It is easily possible to end an AML "package" with an unbounded number * of open scopes (such as when several ASL blocks are closed with * sequential closing braces). We want to terminate each one cleanly. */ ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "AML package complete at Op %p\n", op)); do { if (op) { if (walk_state->ascending_callback != NULL) { walk_state->op = op; walk_state->op_info = acpi_ps_get_opcode_info (op->opcode); walk_state->opcode = op->opcode; status = walk_state->ascending_callback (walk_state); status = acpi_ps_next_parse_state (walk_state, op, status); if (status == AE_CTRL_PENDING) { status = AE_OK; goto close_this_op; } if (status == AE_CTRL_TERMINATE) { status = AE_OK; /* Clean up */ do { if (op) { acpi_ps_complete_this_op (walk_state, op); } acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types, &walk_state->arg_count); } while (op); return_ACPI_STATUS (status); } else if (ACPI_FAILURE (status)) { acpi_ps_complete_this_op (walk_state, op); return_ACPI_STATUS (status); } } acpi_ps_complete_this_op (walk_state, op); } acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types, &walk_state->arg_count); } while (op); return_ACPI_STATUS (status); } /******************************************************************************* * * FUNCTION: Acpi_ps_parse_aml * * PARAMETERS: Start_scope - The starting point of the parse. Becomes the * root of the parsed op tree. * Aml - Pointer to the raw AML code to parse * Aml_size - Length of the AML to parse * * * RETURN: Status * * DESCRIPTION: Parse raw AML and return a tree of ops * ******************************************************************************/ acpi_status acpi_ps_parse_aml ( acpi_walk_state *walk_state) { acpi_status status; acpi_walk_list walk_list; acpi_walk_list *prev_walk_list = acpi_gbl_current_walk_list; acpi_walk_state *previous_walk_state; FUNCTION_TRACE ("Ps_parse_aml"); ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Entered with Walk_state=%p Aml=%p size=%X\n", walk_state, walk_state->parser_state.aml, walk_state->parser_state.aml_size)); /* Create and initialize a new walk list */ walk_list.walk_state = NULL; walk_list.acquired_mutex_list.prev = NULL; walk_list.acquired_mutex_list.next = NULL; walk_state->walk_list = &walk_list; acpi_ds_push_walk_state (walk_state, &walk_list); /* TBD: [Restructure] TEMP until we pass Walk_state to the interpreter */ acpi_gbl_current_walk_list = &walk_list; /* * Execute the walk loop as long as there is a valid Walk State. This * handles nested control method invocations without recursion. */ ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "State=%p\n", walk_state)); status = AE_OK; while (walk_state) { if (ACPI_SUCCESS (status)) { /* * The Parse_loop executes AML until the method terminates * or calls another method. */ status = acpi_ps_parse_loop (walk_state); } ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Completed one call to walk loop, State=%p\n", walk_state)); if (status == AE_CTRL_TRANSFER) { /* * A method call was detected. * Transfer control to the called control method */ status = acpi_ds_call_control_method (&walk_list, walk_state, NULL); /* * If the transfer to the new method method call worked, a new walk * state was created -- get it */ walk_state = acpi_ds_get_current_walk_state (&walk_list); continue; } else if (status == AE_CTRL_TERMINATE) { status = AE_OK; } /* We are done with this walk, move on to the parent if any */ walk_state = acpi_ds_pop_walk_state (&walk_list); /* Reset the current scope to the beginning of scope stack */ acpi_ds_scope_stack_clear (walk_state); /* * If we just returned from the execution of a control method, * there's lots of cleanup to do */ if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == ACPI_PARSE_EXECUTE) { acpi_ds_terminate_control_method (walk_state); } /* Delete this walk state and all linked control states */ acpi_ps_cleanup_scope (&walk_state->parser_state); previous_walk_state = walk_state; ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Return_value=%p, State=%p\n", walk_state->return_desc, walk_state)); /* Check if we have restarted a preempted walk */ walk_state = acpi_ds_get_current_walk_state (&walk_list); if (walk_state) { if (ACPI_SUCCESS (status)) { /* There is another walk state, restart it */ /* * If the method returned value is not used by the parent, * The object is deleted */ acpi_ds_restart_control_method (walk_state, previous_walk_state->return_desc); walk_state->walk_type |= WALK_METHOD_RESTART; } } /* * Just completed a 1st-level method, save the final internal return * value (if any) */ else if (previous_walk_state->caller_return_desc) { *(previous_walk_state->caller_return_desc) = previous_walk_state->return_desc; /* NULL if no return value */ } else if (previous_walk_state->return_desc) { /* Caller doesn't want it, must delete it */ acpi_ut_remove_reference (previous_walk_state->return_desc); } acpi_ds_delete_walk_state (previous_walk_state); } /* Normal exit */ acpi_ex_release_all_mutexes ((acpi_operand_object *) &walk_list.acquired_mutex_list); acpi_gbl_current_walk_list = prev_walk_list; return_ACPI_STATUS (status); }