WSL2-Linux-Kernel/drivers/acpi/acpica/nsnames.c

304 строки
9.6 KiB
C

/*******************************************************************************
*
* Module Name: nsnames - Name manipulation and search
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2015, 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 "amlcode.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nsnames")
/*******************************************************************************
*
* FUNCTION: acpi_ns_get_external_pathname
*
* PARAMETERS: node - Namespace node whose pathname is needed
*
* RETURN: Pointer to storage containing the fully qualified name of
* the node, In external format (name segments separated by path
* separators.)
*
* DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
* for error and debug statements.
*
******************************************************************************/
char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
{
char *name_buffer;
ACPI_FUNCTION_TRACE_PTR(ns_get_external_pathname, node);
name_buffer = acpi_ns_get_normalized_pathname(node, FALSE);
return_PTR(name_buffer);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_get_pathname_length
*
* PARAMETERS: node - Namespace node
*
* RETURN: Length of path, including prefix
*
* DESCRIPTION: Get the length of the pathname string for this node
*
******************************************************************************/
acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
{
acpi_size size;
ACPI_FUNCTION_ENTRY();
size = acpi_ns_build_normalized_path(node, NULL, 0, FALSE);
return (size);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_handle_to_pathname
*
* PARAMETERS: target_handle - Handle of named object whose name is
* to be found
* buffer - Where the pathname is returned
* no_trailing - Remove trailing '_' for each name
* segment
*
* RETURN: Status, Buffer is filled with pathname if status is AE_OK
*
* DESCRIPTION: Build and return a full namespace pathname
*
******************************************************************************/
acpi_status
acpi_ns_handle_to_pathname(acpi_handle target_handle,
struct acpi_buffer * buffer, u8 no_trailing)
{
acpi_status status;
struct acpi_namespace_node *node;
acpi_size required_size;
ACPI_FUNCTION_TRACE_PTR(ns_handle_to_pathname, target_handle);
node = acpi_ns_validate_handle(target_handle);
if (!node) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Determine size required for the caller buffer */
required_size =
acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
if (!required_size) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Validate/Allocate/Clear caller buffer */
status = acpi_ut_initialize_buffer(buffer, required_size);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Build the path in the caller buffer */
(void)acpi_ns_build_normalized_path(node, buffer->pointer,
required_size, no_trailing);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X]\n",
(char *)buffer->pointer, (u32) required_size));
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_build_normalized_path
*
* PARAMETERS: node - Namespace node
* full_path - Where the path name is returned
* path_size - Size of returned path name buffer
* no_trailing - Remove trailing '_' from each name segment
*
* RETURN: Return 1 if the AML path is empty, otherwise returning (length
* of pathname + 1) which means the 'FullPath' contains a trailing
* null.
*
* DESCRIPTION: Build and return a full namespace pathname.
* Note that if the size of 'FullPath' isn't large enough to
* contain the namespace node's path name, the actual required
* buffer length is returned, and it should be greater than
* 'PathSize'. So callers are able to check the returning value
* to determine the buffer size of 'FullPath'.
*
******************************************************************************/
u32
acpi_ns_build_normalized_path(struct acpi_namespace_node *node,
char *full_path, u32 path_size, u8 no_trailing)
{
u32 length = 0, i;
char name[ACPI_NAME_SIZE];
u8 do_no_trailing;
char c, *left, *right;
struct acpi_namespace_node *next_node;
ACPI_FUNCTION_TRACE_PTR(ns_build_normalized_path, node);
#define ACPI_PATH_PUT8(path, size, byte, length) \
do { \
if ((length) < (size)) \
{ \
(path)[(length)] = (byte); \
} \
(length)++; \
} while (0)
/*
* Make sure the path_size is correct, so that we don't need to
* validate both full_path and path_size.
*/
if (!full_path) {
path_size = 0;
}
if (!node) {
goto build_trailing_null;
}
next_node = node;
while (next_node && next_node != acpi_gbl_root_node) {
if (next_node != node) {
ACPI_PATH_PUT8(full_path, path_size,
AML_DUAL_NAME_PREFIX, length);
}
ACPI_MOVE_32_TO_32(name, &next_node->name);
do_no_trailing = no_trailing;
for (i = 0; i < 4; i++) {
c = name[4 - i - 1];
if (do_no_trailing && c != '_') {
do_no_trailing = FALSE;
}
if (!do_no_trailing) {
ACPI_PATH_PUT8(full_path, path_size, c, length);
}
}
next_node = next_node->parent;
}
ACPI_PATH_PUT8(full_path, path_size, AML_ROOT_PREFIX, length);
/* Reverse the path string */
if (length <= path_size) {
left = full_path;
right = full_path + length - 1;
while (left < right) {
c = *left;
*left++ = *right;
*right-- = c;
}
}
/* Append the trailing null */
build_trailing_null:
ACPI_PATH_PUT8(full_path, path_size, '\0', length);
#undef ACPI_PATH_PUT8
return_UINT32(length);
}
/*******************************************************************************
*
* FUNCTION: acpi_ns_get_normalized_pathname
*
* PARAMETERS: node - Namespace node whose pathname is needed
* no_trailing - Remove trailing '_' from each name segment
*
* RETURN: Pointer to storage containing the fully qualified name of
* the node, In external format (name segments separated by path
* separators.)
*
* DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
* for error and debug statements. All trailing '_' will be
* removed from the full pathname if 'NoTrailing' is specified..
*
******************************************************************************/
char *acpi_ns_get_normalized_pathname(struct acpi_namespace_node *node,
u8 no_trailing)
{
char *name_buffer;
acpi_size size;
ACPI_FUNCTION_TRACE_PTR(ns_get_normalized_pathname, node);
/* Calculate required buffer size based on depth below root */
size = acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
if (!size) {
return_PTR(NULL);
}
/* Allocate a buffer to be returned to caller */
name_buffer = ACPI_ALLOCATE_ZEROED(size);
if (!name_buffer) {
ACPI_ERROR((AE_INFO, "Could not allocate %u bytes", (u32)size));
return_PTR(NULL);
}
/* Build the path in the allocated buffer */
(void)acpi_ns_build_normalized_path(node, name_buffer, size,
no_trailing);
return_PTR(name_buffer);
}