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diff --git a/drivers/acpi/tables/tbutils.c b/drivers/acpi/tables/tbutils.c
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+++ b/drivers/acpi/tables/tbutils.c
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+/******************************************************************************
+ *
+ * Module Name: tbutils - Table manipulation utilities
+ *
+ *****************************************************************************/
+
+/*
+ * 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 <acpi/acpi.h>
+#include <acpi/actables.h>
+
+
+#define _COMPONENT ACPI_TABLES
+ ACPI_MODULE_NAME ("tbutils")
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_tb_handle_to_object
+ *
+ * PARAMETERS: table_id - Id for which the function is searching
+ * table_desc - Pointer to return the matching table
+ * descriptor.
+ *
+ * RETURN: Search the tables to find one with a matching table_id and
+ * return a pointer to that table descriptor.
+ *
+ ******************************************************************************/
+#ifdef ACPI_FUTURE_USAGE
+acpi_status
+acpi_tb_handle_to_object (
+ u16 table_id,
+ struct acpi_table_desc **return_table_desc)
+{
+ u32 i;
+ struct acpi_table_desc *table_desc;
+
+
+ ACPI_FUNCTION_NAME ("tb_handle_to_object");
+
+
+ for (i = 0; i < ACPI_TABLE_MAX; i++) {
+ table_desc = acpi_gbl_table_lists[i].next;
+ while (table_desc) {
+ if (table_desc->table_id == table_id) {
+ *return_table_desc = table_desc;
+ return (AE_OK);
+ }
+
+ table_desc = table_desc->next;
+ }
+ }
+
+ ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "table_id=%X does not exist\n", table_id));
+ return (AE_BAD_PARAMETER);
+}
+#endif /* ACPI_FUTURE_USAGE */
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_tb_validate_table_header
+ *
+ * PARAMETERS: table_header - Logical pointer to the table
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Check an ACPI table header for validity
+ *
+ * NOTE: Table pointers are validated as follows:
+ * 1) Table pointer must point to valid physical memory
+ * 2) Signature must be 4 ASCII chars, even if we don't recognize the
+ * name
+ * 3) Table must be readable for length specified in the header
+ * 4) Table checksum must be valid (with the exception of the FACS
+ * which has no checksum because it contains variable fields)
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_tb_validate_table_header (
+ struct acpi_table_header *table_header)
+{
+ acpi_name signature;
+
+
+ ACPI_FUNCTION_NAME ("tb_validate_table_header");
+
+
+ /* Verify that this is a valid address */
+
+ if (!acpi_os_readable (table_header, sizeof (struct acpi_table_header))) {
+ ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+ "Cannot read table header at %p\n", table_header));
+ return (AE_BAD_ADDRESS);
+ }
+
+ /* Ensure that the signature is 4 ASCII characters */
+
+ ACPI_MOVE_32_TO_32 (&signature, table_header->signature);
+ if (!acpi_ut_valid_acpi_name (signature)) {
+ ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+ "Table signature at %p [%p] has invalid characters\n",
+ table_header, &signature));
+
+ ACPI_REPORT_WARNING (("Invalid table signature found: [%4.4s]\n",
+ (char *) &signature));
+ ACPI_DUMP_BUFFER (table_header, sizeof (struct acpi_table_header));
+ return (AE_BAD_SIGNATURE);
+ }
+
+ /* Validate the table length */
+
+ if (table_header->length < sizeof (struct acpi_table_header)) {
+ ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+ "Invalid length in table header %p name %4.4s\n",
+ table_header, (char *) &signature));
+
+ ACPI_REPORT_WARNING (("Invalid table header length (0x%X) found\n",
+ (u32) table_header->length));
+ ACPI_DUMP_BUFFER (table_header, sizeof (struct acpi_table_header));
+ return (AE_BAD_HEADER);
+ }
+
+ return (AE_OK);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_tb_verify_table_checksum
+ *
+ * PARAMETERS: *table_header - ACPI table to verify
+ *
+ * RETURN: 8 bit checksum of table
+ *
+ * DESCRIPTION: Does an 8 bit checksum of table and returns status. A correct
+ * table should have a checksum of 0.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_tb_verify_table_checksum (
+ struct acpi_table_header *table_header)
+{
+ u8 checksum;
+ acpi_status status = AE_OK;
+
+
+ ACPI_FUNCTION_TRACE ("tb_verify_table_checksum");
+
+
+ /* Compute the checksum on the table */
+
+ checksum = acpi_tb_checksum (table_header, table_header->length);
+
+ /* Return the appropriate exception */
+
+ if (checksum) {
+ ACPI_REPORT_WARNING (("Invalid checksum in table [%4.4s] (%02X, sum %02X is not zero)\n",
+ table_header->signature, (u32) table_header->checksum, (u32) checksum));
+
+ status = AE_BAD_CHECKSUM;
+ }
+ return_ACPI_STATUS (status);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_tb_checksum
+ *
+ * PARAMETERS: Buffer - Buffer to checksum
+ * Length - Size of the buffer
+ *
+ * RETURNS 8 bit checksum of buffer
+ *
+ * DESCRIPTION: Computes an 8 bit checksum of the buffer(length) and returns it.
+ *
+ ******************************************************************************/
+
+u8
+acpi_tb_checksum (
+ void *buffer,
+ u32 length)
+{
+ const u8 *limit;
+ const u8 *rover;
+ u8 sum = 0;
+
+
+ if (buffer && length) {
+ /* Buffer and Length are valid */
+
+ limit = (u8 *) buffer + length;
+
+ for (rover = buffer; rover < limit; rover++) {
+ sum = (u8) (sum + *rover);
+ }
+ }
+ return (sum);
+}
+
+