linux/drivers/acpi/executer/exnames.c
Robert Moore 88ac00f5a8 ACPICA 20050526 from Bob Moore <robert.moore@intel.com>
Implemented support to execute Type 1 and Type 2 AML
opcodes appearing at the module level (not within a control
method.)  These opcodes are executed exactly once at the
time the table is loaded. This type of code was legal up
until the release of ACPI 2.0B (2002) and is now supported
within ACPI CA in order to provide backwards compatibility
with earlier BIOS implementations. This eliminates the
"Encountered executable code at module level" warning that
was previously generated upon detection of such code.

Fixed a problem in the interpreter where an AE_NOT_FOUND
exception could inadvertently be generated during the
lookup of namespace objects in the second pass parse of
ACPI tables and control methods. It appears that this
problem could occur during the resolution of forward
references to namespace objects.

Added the ACPI_MUTEX_DEBUG #ifdef to the
acpi_ut_release_mutex function, corresponding to the same
the deadlock detection debug code to be compiled out in
the normal case, improving mutex performance (and overall
subsystem performance) considerably.  As suggested by
Alexey Starikovskiy.

Implemented a handful of miscellaneous fixes for possible
memory leaks on error conditions and error handling
control paths. These fixes were suggested by FreeBSD and
the Coverity Prevent source code analysis tool.

Added a check for a null RSDT pointer in
acpi_get_firmware_table (tbxfroot.c) to prevent a fault
in this error case.

Signed-off-by Len Brown <len.brown@intel.com>
2005-07-13 16:46:34 -04:00

454 lines
12 KiB
C

/******************************************************************************
*
* Module Name: exnames - interpreter/scanner name load/execute
*
*****************************************************************************/
/*
* 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/acinterp.h>
#include <acpi/amlcode.h>
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME ("exnames")
/* Local prototypes */
static char *
acpi_ex_allocate_name_string (
u32 prefix_count,
u32 num_name_segs);
static acpi_status
acpi_ex_name_segment (
u8 **in_aml_address,
char *name_string);
/*******************************************************************************
*
* FUNCTION: acpi_ex_allocate_name_string
*
* PARAMETERS: prefix_count - Count of parent levels. Special cases:
* (-1)==root, 0==none
* num_name_segs - count of 4-character name segments
*
* RETURN: A pointer to the allocated string segment. This segment must
* be deleted by the caller.
*
* DESCRIPTION: Allocate a buffer for a name string. Ensure allocated name
* string is long enough, and set up prefix if any.
*
******************************************************************************/
static char *
acpi_ex_allocate_name_string (
u32 prefix_count,
u32 num_name_segs)
{
char *temp_ptr;
char *name_string;
u32 size_needed;
ACPI_FUNCTION_TRACE ("ex_allocate_name_string");
/*
* Allow room for all \ and ^ prefixes, all segments and a multi_name_prefix.
* Also, one byte for the null terminator.
* This may actually be somewhat longer than needed.
*/
if (prefix_count == ACPI_UINT32_MAX) {
/* Special case for root */
size_needed = 1 + (ACPI_NAME_SIZE * num_name_segs) + 2 + 1;
}
else {
size_needed = prefix_count + (ACPI_NAME_SIZE * num_name_segs) + 2 + 1;
}
/*
* Allocate a buffer for the name.
* This buffer must be deleted by the caller!
*/
name_string = ACPI_MEM_ALLOCATE (size_needed);
if (!name_string) {
ACPI_REPORT_ERROR ((
"ex_allocate_name_string: Could not allocate size %d\n", size_needed));
return_PTR (NULL);
}
temp_ptr = name_string;
/* Set up Root or Parent prefixes if needed */
if (prefix_count == ACPI_UINT32_MAX) {
*temp_ptr++ = AML_ROOT_PREFIX;
}
else {
while (prefix_count--) {
*temp_ptr++ = AML_PARENT_PREFIX;
}
}
/* Set up Dual or Multi prefixes if needed */
if (num_name_segs > 2) {
/* Set up multi prefixes */
*temp_ptr++ = AML_MULTI_NAME_PREFIX_OP;
*temp_ptr++ = (char) num_name_segs;
}
else if (2 == num_name_segs) {
/* Set up dual prefixes */
*temp_ptr++ = AML_DUAL_NAME_PREFIX;
}
/*
* Terminate string following prefixes. acpi_ex_name_segment() will
* append the segment(s)
*/
*temp_ptr = 0;
return_PTR (name_string);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_name_segment
*
* PARAMETERS: in_aml_address - Pointer to the name in the AML code
* name_string - Where to return the name. The name is appended
* to any existing string to form a namepath
*
* RETURN: Status
*
* DESCRIPTION: Extract an ACPI name (4 bytes) from the AML byte stream
*
******************************************************************************/
static acpi_status
acpi_ex_name_segment (
u8 **in_aml_address,
char *name_string)
{
char *aml_address = (void *) *in_aml_address;
acpi_status status = AE_OK;
u32 index;
char char_buf[5];
ACPI_FUNCTION_TRACE ("ex_name_segment");
/*
* If first character is a digit, then we know that we aren't looking at a
* valid name segment
*/
char_buf[0] = *aml_address;
if ('0' <= char_buf[0] && char_buf[0] <= '9') {
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "leading digit: %c\n", char_buf[0]));
return_ACPI_STATUS (AE_CTRL_PENDING);
}
ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "Bytes from stream:\n"));
for (index = 0;
(index < ACPI_NAME_SIZE) && (acpi_ut_valid_acpi_character (*aml_address));
index++) {
char_buf[index] = *aml_address++;
ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "%c\n", char_buf[index]));
}
/* Valid name segment */
if (index == 4) {
/* Found 4 valid characters */
char_buf[4] = '\0';
if (name_string) {
ACPI_STRCAT (name_string, char_buf);
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"Appended to - %s \n", name_string));
}
else {
ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
"No Name string - %s \n", char_buf));
}
}
else if (index == 0) {
/*
* First character was not a valid name character,
* so we are looking at something other than a name.
*/
ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
"Leading character is not alpha: %02Xh (not a name)\n",
char_buf[0]));
status = AE_CTRL_PENDING;
}
else {
/*
* Segment started with one or more valid characters, but fewer than
* the required 4
*/
status = AE_AML_BAD_NAME;
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Bad character %02x in name, at %p\n",
*aml_address, aml_address));
}
*in_aml_address = (u8 *) aml_address;
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_get_name_string
*
* PARAMETERS: data_type - Object type to be associated with this
* name
* in_aml_address - Pointer to the namestring in the AML code
* out_name_string - Where the namestring is returned
* out_name_length - Length of the returned string
*
* RETURN: Status, namestring and length
*
* DESCRIPTION: Extract a full namepath from the AML byte stream,
* including any prefixes.
*
******************************************************************************/
acpi_status
acpi_ex_get_name_string (
acpi_object_type data_type,
u8 *in_aml_address,
char **out_name_string,
u32 *out_name_length)
{
acpi_status status = AE_OK;
u8 *aml_address = in_aml_address;
char *name_string = NULL;
u32 num_segments;
u32 prefix_count = 0;
u8 has_prefix = FALSE;
ACPI_FUNCTION_TRACE_PTR ("ex_get_name_string", aml_address);
if (ACPI_TYPE_LOCAL_REGION_FIELD == data_type ||
ACPI_TYPE_LOCAL_BANK_FIELD == data_type ||
ACPI_TYPE_LOCAL_INDEX_FIELD == data_type) {
/* Disallow prefixes for types associated with field_unit names */
name_string = acpi_ex_allocate_name_string (0, 1);
if (!name_string) {
status = AE_NO_MEMORY;
}
else {
status = acpi_ex_name_segment (&aml_address, name_string);
}
}
else {
/*
* data_type is not a field name.
* Examine first character of name for root or parent prefix operators
*/
switch (*aml_address) {
case AML_ROOT_PREFIX:
ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "root_prefix(\\) at %p\n",
aml_address));
/*
* Remember that we have a root_prefix --
* see comment in acpi_ex_allocate_name_string()
*/
aml_address++;
prefix_count = ACPI_UINT32_MAX;
has_prefix = TRUE;
break;
case AML_PARENT_PREFIX:
/* Increment past possibly multiple parent prefixes */
do {
ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "parent_prefix (^) at %p\n",
aml_address));
aml_address++;
prefix_count++;
} while (*aml_address == AML_PARENT_PREFIX);
has_prefix = TRUE;
break;
default:
/* Not a prefix character */
break;
}
/* Examine first character of name for name segment prefix operator */
switch (*aml_address) {
case AML_DUAL_NAME_PREFIX:
ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "dual_name_prefix at %p\n",
aml_address));
aml_address++;
name_string = acpi_ex_allocate_name_string (prefix_count, 2);
if (!name_string) {
status = AE_NO_MEMORY;
break;
}
/* Indicate that we processed a prefix */
has_prefix = TRUE;
status = acpi_ex_name_segment (&aml_address, name_string);
if (ACPI_SUCCESS (status)) {
status = acpi_ex_name_segment (&aml_address, name_string);
}
break;
case AML_MULTI_NAME_PREFIX_OP:
ACPI_DEBUG_PRINT ((ACPI_DB_LOAD, "multi_name_prefix at %p\n",
aml_address));
/* Fetch count of segments remaining in name path */
aml_address++;
num_segments = *aml_address;
name_string = acpi_ex_allocate_name_string (prefix_count, num_segments);
if (!name_string) {
status = AE_NO_MEMORY;
break;
}
/* Indicate that we processed a prefix */
aml_address++;
has_prefix = TRUE;
while (num_segments &&
(status = acpi_ex_name_segment (&aml_address, name_string)) ==
AE_OK) {
num_segments--;
}
break;
case 0:
/* null_name valid as of 8-12-98 ASL/AML Grammar Update */
if (prefix_count == ACPI_UINT32_MAX) {
ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
"name_seg is \"\\\" followed by NULL\n"));
}
/* Consume the NULL byte */
aml_address++;
name_string = acpi_ex_allocate_name_string (prefix_count, 0);
if (!name_string) {
status = AE_NO_MEMORY;
break;
}
break;
default:
/* Name segment string */
name_string = acpi_ex_allocate_name_string (prefix_count, 1);
if (!name_string) {
status = AE_NO_MEMORY;
break;
}
status = acpi_ex_name_segment (&aml_address, name_string);
break;
}
}
if (AE_CTRL_PENDING == status && has_prefix) {
/* Ran out of segments after processing a prefix */
ACPI_REPORT_ERROR (
("ex_do_name: Malformed Name at %p\n", name_string));
status = AE_AML_BAD_NAME;
}
if (ACPI_FAILURE (status)) {
if (name_string) {
ACPI_MEM_FREE (name_string);
}
return_ACPI_STATUS (status);
}
*out_name_string = name_string;
*out_name_length = (u32) (aml_address - in_aml_address);
return_ACPI_STATUS (status);
}