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linux/drivers/acpi/acpica/nsrepair.c
Lin Ming 0240d7b4f2 ACPICA: Add repair for bad _MAT buffers
_MAT can inadvertently return an Integer instead of a Buffer
if the return value has been read from a Field whose width is
less than or equal to the global integer width (32 or 64 bits).
ACPICA BZ 810.

http://www.acpica.org/bugzilla/show_bug.cgi?id=810

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-11-24 20:30:03 -05:00

262 lines
8.8 KiB
C

/******************************************************************************
*
* Module Name: nsrepair - Repair for objects returned by predefined methods
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2009, Intel Corp.
* 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 "accommon.h"
#include "acnamesp.h"
#include "acinterp.h"
#include "acpredef.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nsrepair")
/*******************************************************************************
*
* FUNCTION: acpi_ns_repair_object
*
* PARAMETERS: Data - Pointer to validation data structure
* expected_btypes - Object types expected
* package_index - Index of object within parent package (if
* applicable - ACPI_NOT_PACKAGE_ELEMENT
* otherwise)
* return_object_ptr - Pointer to the object returned from the
* evaluation of a method or object
*
* RETURN: Status. AE_OK if repair was successful.
*
* DESCRIPTION: Attempt to repair/convert a return object of a type that was
* not expected.
*
******************************************************************************/
acpi_status
acpi_ns_repair_object(struct acpi_predefined_data *data,
u32 expected_btypes,
u32 package_index,
union acpi_operand_object **return_object_ptr)
{
union acpi_operand_object *return_object = *return_object_ptr;
union acpi_operand_object *new_object;
acpi_size length;
acpi_status status;
/*
* At this point, we know that the type of the returned object was not
* one of the expected types for this predefined name. Attempt to
* repair the object. Only a limited number of repairs are possible.
*/
switch (return_object->common.type) {
case ACPI_TYPE_BUFFER:
/* Does the method/object legally return a string? */
if (!(expected_btypes & ACPI_RTYPE_STRING)) {
return (AE_AML_OPERAND_TYPE);
}
/*
* Have a Buffer, expected a String, convert. Use a to_string
* conversion, no transform performed on the buffer data. The best
* example of this is the _BIF method, where the string data from
* the battery is often (incorrectly) returned as buffer object(s).
*/
length = 0;
while ((length < return_object->buffer.length) &&
(return_object->buffer.pointer[length])) {
length++;
}
/* Allocate a new string object */
new_object = acpi_ut_create_string_object(length);
if (!new_object) {
return (AE_NO_MEMORY);
}
/*
* Copy the raw buffer data with no transform. String is already NULL
* terminated at Length+1.
*/
ACPI_MEMCPY(new_object->string.pointer,
return_object->buffer.pointer, length);
break;
case ACPI_TYPE_INTEGER:
/* 1) Does the method/object legally return a buffer? */
if (expected_btypes & ACPI_RTYPE_BUFFER) {
/*
* Convert the Integer to a packed-byte buffer. _MAT needs
* this sometimes, if a read has been performed on a Field
* object that is less than or equal to the global integer
* size (32 or 64 bits).
*/
status =
acpi_ex_convert_to_buffer(return_object,
&new_object);
if (ACPI_FAILURE(status)) {
return (status);
}
}
/* 2) Does the method/object legally return a string? */
else if (expected_btypes & ACPI_RTYPE_STRING) {
/*
* The only supported Integer-to-String conversion is to convert
* an integer of value 0 to a NULL string. The last element of
* _BIF and _BIX packages occasionally need this fix.
*/
if (return_object->integer.value != 0) {
return (AE_AML_OPERAND_TYPE);
}
/* Allocate a new NULL string object */
new_object = acpi_ut_create_string_object(0);
if (!new_object) {
return (AE_NO_MEMORY);
}
} else {
return (AE_AML_OPERAND_TYPE);
}
break;
default:
/* We cannot repair this object */
return (AE_AML_OPERAND_TYPE);
}
/* Object was successfully repaired */
/*
* If the original object is a package element, we need to:
* 1. Set the reference count of the new object to match the
* reference count of the old object.
* 2. Decrement the reference count of the original object.
*/
if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
new_object->common.reference_count =
return_object->common.reference_count;
if (return_object->common.reference_count > 1) {
return_object->common.reference_count--;
}
ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
"Converted %s to expected %s at index %u",
acpi_ut_get_object_type_name
(return_object),
acpi_ut_get_object_type_name(new_object),
package_index));
} else {
ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
"Converted %s to expected %s",
acpi_ut_get_object_type_name
(return_object),
acpi_ut_get_object_type_name
(new_object)));
}
/* Delete old object, install the new return object */
acpi_ut_remove_reference(return_object);
*return_object_ptr = new_object;
data->flags |= ACPI_OBJECT_REPAIRED;
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_repair_package_list
*
* PARAMETERS: Data - Pointer to validation data structure
* obj_desc_ptr - Pointer to the object to repair. The new
* package object is returned here,
* overwriting the old object.
*
* RETURN: Status, new object in *obj_desc_ptr
*
* DESCRIPTION: Repair a common problem with objects that are defined to return
* a variable-length Package of Packages. If the variable-length
* is one, some BIOS code mistakenly simply declares a single
* Package instead of a Package with one sub-Package. This
* function attempts to repair this error by wrapping a Package
* object around the original Package, creating the correct
* Package with one sub-Package.
*
* Names that can be repaired in this manner include:
* _ALR, _CSD, _HPX, _MLS, _PRT, _PSS, _TRT, TSS
*
******************************************************************************/
acpi_status
acpi_ns_repair_package_list(struct acpi_predefined_data *data,
union acpi_operand_object **obj_desc_ptr)
{
union acpi_operand_object *pkg_obj_desc;
/*
* Create the new outer package and populate it. The new package will
* have a single element, the lone subpackage.
*/
pkg_obj_desc = acpi_ut_create_package_object(1);
if (!pkg_obj_desc) {
return (AE_NO_MEMORY);
}
pkg_obj_desc->package.elements[0] = *obj_desc_ptr;
/* Return the new object in the object pointer */
*obj_desc_ptr = pkg_obj_desc;
data->flags |= ACPI_OBJECT_REPAIRED;
ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
"Incorrectly formed Package, attempting repair"));
return (AE_OK);
}