linux/drivers/acpi/acpica/exoparg3.c

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: exoparg3 - AML execution - opcodes with 3 arguments
 *
 * Copyright (C) 2000 - 2018, Intel Corp.
 *
 *****************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acinterp.h"
#include "acparser.h"
#include "amlcode.h"

#define _COMPONENT          ACPI_EXECUTER
ACPI_MODULE_NAME("exoparg3")

/*!
 * Naming convention for AML interpreter execution routines.
 *
 * The routines that begin execution of AML opcodes are named with a common
 * convention based upon the number of arguments, the number of target operands,
 * and whether or not a value is returned:
 *
 *      AcpiExOpcode_xA_yT_zR
 *
 * Where:
 *
 * xA - ARGUMENTS:    The number of arguments (input operands) that are
 *                    required for this opcode type (1 through 6 args).
 * yT - TARGETS:      The number of targets (output operands) that are required
 *                    for this opcode type (0, 1, or 2 targets).
 * zR - RETURN VALUE: Indicates whether this opcode type returns a value
 *                    as the function return (0 or 1).
 *
 * The AcpiExOpcode* functions are called via the Dispatcher component with
 * fully resolved operands.
!*/
/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_opcode_3A_0T_0R
 *
 * PARAMETERS:  walk_state          - Current walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Execute Triadic operator (3 operands)
 *
 ******************************************************************************/
acpi_status acpi_ex_opcode_3A_0T_0R(struct acpi_walk_state *walk_state)
{
	union acpi_operand_object **operand = &walk_state->operands[0];
	struct acpi_signal_fatal_info *fatal;
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE_STR(ex_opcode_3A_0T_0R,
				acpi_ps_get_opcode_name(walk_state->opcode));

	switch (walk_state->opcode) {
	case AML_FATAL_OP:	/* Fatal (fatal_type fatal_code fatal_arg) */

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "FatalOp: Type %X Code %X Arg %X "
				  "<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n",
				  (u32)operand[0]->integer.value,
				  (u32)operand[1]->integer.value,
				  (u32)operand[2]->integer.value));

		fatal = ACPI_ALLOCATE(sizeof(struct acpi_signal_fatal_info));
		if (fatal) {
			fatal->type = (u32) operand[0]->integer.value;
			fatal->code = (u32) operand[1]->integer.value;
			fatal->argument = (u32) operand[2]->integer.value;
		}

		/* Always signal the OS! */

		status = acpi_os_signal(ACPI_SIGNAL_FATAL, fatal);

		/* Might return while OS is shutting down, just continue */

		ACPI_FREE(fatal);
		goto cleanup;

	case AML_EXTERNAL_OP:
		/*
		 * If the interpreter sees this opcode, just ignore it. The External
		 * op is intended for use by disassemblers in order to properly
		 * disassemble control method invocations. The opcode or group of
		 * opcodes should be surrounded by an "if (0)" clause to ensure that
		 * AML interpreters never see the opcode. Thus, something is
		 * wrong if an external opcode ever gets here.
		 */
		ACPI_ERROR((AE_INFO, "Executed External Op"));
		status = AE_OK;
		goto cleanup;

	default:

		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
			    walk_state->opcode));

		status = AE_AML_BAD_OPCODE;
		goto cleanup;
	}

cleanup:

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_opcode_3A_1T_1R
 *
 * PARAMETERS:  walk_state          - Current walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Execute Triadic operator (3 operands)
 *
 ******************************************************************************/

acpi_status acpi_ex_opcode_3A_1T_1R(struct acpi_walk_state *walk_state)
{
	union acpi_operand_object **operand = &walk_state->operands[0];
	union acpi_operand_object *return_desc = NULL;
	char *buffer = NULL;
	acpi_status status = AE_OK;
	u64 index;
	acpi_size length;

	ACPI_FUNCTION_TRACE_STR(ex_opcode_3A_1T_1R,
				acpi_ps_get_opcode_name(walk_state->opcode));

	switch (walk_state->opcode) {
	case AML_MID_OP:	/* Mid (Source[0], Index[1], Length[2], Result[3]) */
		/*
		 * Create the return object. The Source operand is guaranteed to be
		 * either a String or a Buffer, so just use its type.
		 */
		return_desc = acpi_ut_create_internal_object((operand[0])->
							     common.type);
		if (!return_desc) {
			status = AE_NO_MEMORY;
			goto cleanup;
		}

		/* Get the Integer values from the objects */

		index = operand[1]->integer.value;
		length = (acpi_size)operand[2]->integer.value;

		/*
		 * If the index is beyond the length of the String/Buffer, or if the
		 * requested length is zero, return a zero-length String/Buffer
		 */
		if (index >= operand[0]->string.length) {
			length = 0;
		}

		/* Truncate request if larger than the actual String/Buffer */

		else if ((index + length) > operand[0]->string.length) {
			length =
			    (acpi_size)operand[0]->string.length -
			    (acpi_size)index;
		}

		/* Strings always have a sub-pointer, not so for buffers */

		switch ((operand[0])->common.type) {
		case ACPI_TYPE_STRING:

			/* Always allocate a new buffer for the String */

			buffer = ACPI_ALLOCATE_ZEROED((acpi_size)length + 1);
			if (!buffer) {
				status = AE_NO_MEMORY;
				goto cleanup;
			}
			break;

		case ACPI_TYPE_BUFFER:

			/* If the requested length is zero, don't allocate a buffer */

			if (length > 0) {

				/* Allocate a new buffer for the Buffer */

				buffer = ACPI_ALLOCATE_ZEROED(length);
				if (!buffer) {
					status = AE_NO_MEMORY;
					goto cleanup;
				}
			}
			break;

		default:	/* Should not happen */

			status = AE_AML_OPERAND_TYPE;
			goto cleanup;
		}

		if (buffer) {

			/* We have a buffer, copy the portion requested */

			memcpy(buffer,
			       operand[0]->string.pointer + index, length);
		}

		/* Set the length of the new String/Buffer */

		return_desc->string.pointer = buffer;
		return_desc->string.length = (u32) length;

		/* Mark buffer initialized */

		return_desc->buffer.flags |= AOPOBJ_DATA_VALID;
		break;

	default:

		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
			    walk_state->opcode));

		status = AE_AML_BAD_OPCODE;
		goto cleanup;
	}

	/* Store the result in the target */

	status = acpi_ex_store(return_desc, operand[3], walk_state);

cleanup:

	/* Delete return object on error */

	if (ACPI_FAILURE(status) || walk_state->result_obj) {
		acpi_ut_remove_reference(return_desc);
		walk_state->result_obj = NULL;
	} else {
		/* Set the return object and exit */

		walk_state->result_obj = return_desc;
	}

	return_ACPI_STATUS(status);
}