/*******************************************************************************
*
* Module Name: nsxfeval - Public interfaces to the ACPI subsystem
* ACPI Object evaluation interfaces
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2013, 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 <linux/export.h>
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acinterp.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("nsxfeval")
/* Local prototypes */
static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
/*******************************************************************************
*
* FUNCTION: acpi_evaluate_object_typed
*
* PARAMETERS: handle - Object handle (optional)
* pathname - Object pathname (optional)
* external_params - List of parameters to pass to method,
* terminated by NULL. May be NULL
* if no parameters are being passed.
* return_buffer - Where to put method's return value (if
* any). If NULL, no value is returned.
* return_type - Expected type of return object
*
* RETURN: Status
*
* DESCRIPTION: Find and evaluate the given object, passing the given
* parameters if necessary. One of "Handle" or "Pathname" must
* be valid (non-null)
*
******************************************************************************/
acpi_status
acpi_evaluate_object_typed(acpi_handle handle,
acpi_string pathname,
struct acpi_object_list *external_params,
struct acpi_buffer *return_buffer,
acpi_object_type return_type)
{
acpi_status status;
u8 must_free = FALSE;
ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
/* Return buffer must be valid */
if (!return_buffer) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
must_free = TRUE;
}
/* Evaluate the object */
status =
acpi_evaluate_object(handle, pathname, external_params,
return_buffer);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Type ANY means "don't care" */
if (return_type == ACPI_TYPE_ANY) {
return_ACPI_STATUS(AE_OK);
}
if (return_buffer->length == 0) {
/* Error because caller specifically asked for a return value */
ACPI_ERROR((AE_INFO, "No return value"));
return_ACPI_STATUS(AE_NULL_OBJECT);
}
/* Examine the object type returned from evaluate_object */
if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
return_ACPI_STATUS(AE_OK);
}
/* Return object type does not match requested type */
ACPI_ERROR((AE_INFO,
"Incorrect return type [%s] requested [%s]",
acpi_ut_get_type_name(((union acpi_object *)return_buffer->
pointer)->type),
acpi_ut_get_type_name(return_type)));
if (must_free) {
/* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
ACPI_FREE(return_buffer->pointer);
return_buffer->pointer = NULL;
}
return_buffer->length = 0;
return_ACPI_STATUS(AE_TYPE);
}
ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
/*******************************************************************************
*
* FUNCTION: acpi_evaluate_object
*
* PARAMETERS: handle - Object handle (optional)
* pathname - Object pathname (optional)
* external_params - List of parameters to pass to method,
* terminated by NULL. May be NULL
* if no parameters are being passed.
* return_buffer - Where to put method's return value (if
* any). If NULL, no value is returned.
*
* RETURN: Status
*
* DESCRIPTION: Find and evaluate the given object, passing the given
* parameters if necessary. One of "Handle" or "Pathname" must
* be valid (non-null)
*
******************************************************************************/
acpi_status
acpi_evaluate_object(acpi_handle handle,
acpi_string pathname,
struct acpi_object_list *external_params,
struct acpi_buffer *return_buffer)
{
acpi_status status;
struct acpi_evaluate_info *info;
acpi_size buffer_space_needed;
u32 i;
ACPI_FUNCTION_TRACE(acpi_evaluate_object);
/* Allocate and initialize the evaluation information block */
info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
if (!info) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
info->pathname = pathname;
/* Convert and validate the device handle */
info->prefix_node = acpi_ns_validate_handle(handle);
if (!info->prefix_node) {
status = AE_BAD_PARAMETER;
goto cleanup;
}
/*
* If there are parameters to be passed to a control method, the external
* objects must all be converted to internal objects
*/
if (external_params && external_params->count) {
/*
* Allocate a new parameter block for the internal objects
* Add 1 to count to allow for null terminated internal list
*/
info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
external_params->
count +
1) * sizeof(void *));
if (!info->parameters) {
status = AE_NO_MEMORY;
goto cleanup;
}
/* Convert each external object in the list to an internal object */
for (i = 0; i < external_params->count; i++) {
status =
acpi_ut_copy_eobject_to_iobject(&external_params->
pointer[i],
&info->
parameters[i]);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
}
info->parameters[external_params->count] = NULL;
}
/*
* Three major cases:
* 1) Fully qualified pathname
* 2) No handle, not fully qualified pathname (error)
* 3) Valid handle
*/
if ((pathname) && (ACPI_IS_ROOT_PREFIX(pathname[0]))) {
/* The path is fully qualified, just evaluate by name */
info->prefix_node = NULL;
status = acpi_ns_evaluate(info);
} else if (!handle) {
/*
* A handle is optional iff a fully qualified pathname is specified.
* Since we've already handled fully qualified names above, this is
* an error
*/
if (!pathname) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Both Handle and Pathname are NULL"));
} else {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Null Handle with relative pathname [%s]",
pathname));
}
status = AE_BAD_PARAMETER;
} else {
/* We have a namespace a node and a possible relative path */
status = acpi_ns_evaluate(info);
}
/*
* If we are expecting a return value, and all went well above,
* copy the return value to an external object.
*/
if (return_buffer) {
if (!info->return_object) {
return_buffer->length = 0;
} else {
if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
ACPI_DESC_TYPE_NAMED) {
/*
* If we received a NS Node as a return object, this means that
* the object we are evaluating has nothing interesting to
* return (such as a mutex, etc.) We return an error because
* these types are essentially unsupported by this interface.
* We don't check up front because this makes it easier to add
* support for various types at a later date if necessary.
*/
status = AE_TYPE;
info->return_object = NULL; /* No need to delete a NS Node */
return_buffer->length = 0;
}
if (ACPI_SUCCESS(status)) {
/* Dereference Index and ref_of references */
acpi_ns_resolve_references(info);
/* Get the size of the returned object */
status =
acpi_ut_get_object_size(info->return_object,
&buffer_space_needed);
if (ACPI_SUCCESS(status)) {
/* Validate/Allocate/Clear caller buffer */
status =
acpi_ut_initialize_buffer
(return_buffer,
buffer_space_needed);
if (ACPI_FAILURE(status)) {
/*
* Caller's buffer is too small or a new one can't
* be allocated
*/
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Needed buffer size %X, %s\n",
(u32)
buffer_space_needed,
acpi_format_exception
(status)));
} else {
/* We have enough space for the object, build it */
status =
acpi_ut_copy_iobject_to_eobject
(info->return_object,
return_buffer);
}
}
}
}
}
if (info->return_object) {
/*
* Delete the internal return object. NOTE: Interpreter must be
* locked to avoid race condition.
*/
acpi_ex_enter_interpreter();
/* Remove one reference on the return object (should delete it) */
acpi_ut_remove_reference(info->return_object);
acpi_ex_exit_interpreter();
}
cleanup:
/* Free the input parameter list (if we created one) */
if (info->parameters) {
/* Free the allocated parameter block */
acpi_ut_delete_internal_object_list(info->parameters);
}
ACPI_FREE(info);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
/*******************************************************************************
*
* FUNCTION: acpi_ns_resolve_references
*
* PARAMETERS: info - Evaluation info block
*
* RETURN: Info->return_object is replaced with the dereferenced object
*
* DESCRIPTION: Dereference certain reference objects. Called before an
* internal return object is converted to an external union acpi_object.
*
* Performs an automatic dereference of Index and ref_of reference objects.
* These reference objects are not supported by the union acpi_object, so this is a
* last resort effort to return something useful. Also, provides compatibility
* with other ACPI implementations.
*
* NOTE: does not handle references within returned package objects or nested
* references, but this support could be added later if found to be necessary.
*
******************************************************************************/
static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
{
union acpi_operand_object *obj_desc = NULL;
struct acpi_namespace_node *node;
/* We are interested in reference objects only */
if ((info->return_object)->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
return;
}
/*
* Two types of references are supported - those created by Index and
* ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
* to an union acpi_object, so it is not dereferenced here. A ddb_handle
* (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
* an union acpi_object.
*/
switch (info->return_object->reference.class) {
case ACPI_REFCLASS_INDEX:
obj_desc = *(info->return_object->reference.where);
break;
case ACPI_REFCLASS_REFOF:
node = info->return_object->reference.object;
if (node) {
obj_desc = node->object;
}
break;
default:
return;
}
/* Replace the existing reference object */
if (obj_desc) {
acpi_ut_add_reference(obj_desc);
acpi_ut_remove_reference(info->return_object);
info->return_object = obj_desc;
}
return;
}
/*******************************************************************************
*
* FUNCTION: acpi_walk_namespace
*
* PARAMETERS: type - acpi_object_type to search for
* start_object - Handle in namespace where search begins
* max_depth - Depth to which search is to reach
* pre_order_visit - Called during tree pre-order visit
* when an object of "Type" is found
* post_order_visit - Called during tree post-order visit
* when an object of "Type" is found
* context - Passed to user function(s) above
* return_value - Location where return value of
* user_function is put if terminated early
*
* RETURNS Return value from the user_function if terminated early.
* Otherwise, returns NULL.
*
* DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
* starting (and ending) at the object specified by start_handle.
* The callback function is called whenever an object that matches
* the type parameter is found. If the callback function returns
* a non-zero value, the search is terminated immediately and this
* value is returned to the caller.
*
* The point of this procedure is to provide a generic namespace
* walk routine that can be called from multiple places to
* provide multiple services; the callback function(s) can be
* tailored to each task, whether it is a print function,
* a compare function, etc.
*
******************************************************************************/
acpi_status
acpi_walk_namespace(acpi_object_type type,
acpi_handle start_object,
u32 max_depth,
acpi_walk_callback pre_order_visit,
acpi_walk_callback post_order_visit,
void *context, void **return_value)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_walk_namespace);
/* Parameter validation */
if ((type > ACPI_TYPE_LOCAL_MAX) ||
(!max_depth) || (!pre_order_visit && !post_order_visit)) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/*
* Need to acquire the namespace reader lock to prevent interference
* with any concurrent table unloads (which causes the deletion of
* namespace objects). We cannot allow the deletion of a namespace node
* while the user function is using it. The exception to this are the
* nodes created and deleted during control method execution -- these
* nodes are marked as temporary nodes and are ignored by the namespace
* walk. Thus, control methods can be executed while holding the
* namespace deletion lock (and the user function can execute control
* methods.)
*/
status = acpi_ut_acquire_read_lock(&acpi_gbl_namespace_rw_lock);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Lock the namespace around the walk. The namespace will be
* unlocked/locked around each call to the user function - since the user
* function must be allowed to make ACPICA calls itself (for example, it
* will typically execute control methods during device enumeration.)
*/
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
status = acpi_ns_walk_namespace(type, start_object, max_depth,
ACPI_NS_WALK_UNLOCK, pre_order_visit,
post_order_visit, context,
return_value);
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
unlock_and_exit:
(void)acpi_ut_release_read_lock(&acpi_gbl_namespace_rw_lock);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
/*******************************************************************************
*
* FUNCTION: acpi_ns_get_device_callback
*
* PARAMETERS: Callback from acpi_get_device
*
* RETURN: Status
*
* DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
* present devices, or if they specified a HID, it filters based
* on that.
*
******************************************************************************/
static acpi_status
acpi_ns_get_device_callback(acpi_handle obj_handle,
u32 nesting_level,
void *context, void **return_value)
{
struct acpi_get_devices_info *info = context;
acpi_status status;
struct acpi_namespace_node *node;
u32 flags;
struct acpi_pnp_device_id *hid;
struct acpi_pnp_device_id_list *cid;
u32 i;
u8 found;
int no_match;
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
node = acpi_ns_validate_handle(obj_handle);
status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
if (!node) {
return (AE_BAD_PARAMETER);
}
/*
* First, filter based on the device HID and CID.
*
* 01/2010: For this case where a specific HID is requested, we don't
* want to run _STA until we have an actual HID match. Thus, we will
* not unnecessarily execute _STA on devices for which the caller
* doesn't care about. Previously, _STA was executed unconditionally
* on all devices found here.
*
* A side-effect of this change is that now we will continue to search
* for a matching HID even under device trees where the parent device
* would have returned a _STA that indicates it is not present or
* not functioning (thus aborting the search on that branch).
*/
if (info->hid != NULL) {
status = acpi_ut_execute_HID(node, &hid);
if (status == AE_NOT_FOUND) {
return (AE_OK);
} else if (ACPI_FAILURE(status)) {
return (AE_CTRL_DEPTH);
}
no_match = ACPI_STRCMP(hid->string, info->hid);
ACPI_FREE(hid);
if (no_match) {
/*
* HID does not match, attempt match within the
* list of Compatible IDs (CIDs)
*/
status = acpi_ut_execute_CID(node, &cid);
if (status == AE_NOT_FOUND) {
return (AE_OK);
} else if (ACPI_FAILURE(status)) {
return (AE_CTRL_DEPTH);
}
/* Walk the CID list */
found = FALSE;
for (i = 0; i < cid->count; i++) {
if (ACPI_STRCMP(cid->ids[i].string, info->hid)
== 0) {
/* Found a matching CID */
found = TRUE;
break;
}
}
ACPI_FREE(cid);
if (!found) {
return (AE_OK);
}
}
}
/* Run _STA to determine if device is present */
status = acpi_ut_execute_STA(node, &flags);
if (ACPI_FAILURE(status)) {
return (AE_CTRL_DEPTH);
}
if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
!(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
/*
* Don't examine the children of the device only when the
* device is neither present nor functional. See ACPI spec,
* description of _STA for more information.
*/
return (AE_CTRL_DEPTH);
}
/* We have a valid device, invoke the user function */
status = info->user_function(obj_handle, nesting_level, info->context,
return_value);
return (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_get_devices
*
* PARAMETERS: HID - HID to search for. Can be NULL.
* user_function - Called when a matching object is found
* context - Passed to user function
* return_value - Location where return value of
* user_function is put if terminated early
*
* RETURNS Return value from the user_function if terminated early.
* Otherwise, returns NULL.
*
* DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
* starting (and ending) at the object specified by start_handle.
* The user_function is called whenever an object of type
* Device is found. If the user function returns
* a non-zero value, the search is terminated immediately and this
* value is returned to the caller.
*
* This is a wrapper for walk_namespace, but the callback performs
* additional filtering. Please see acpi_ns_get_device_callback.
*
******************************************************************************/
acpi_status
acpi_get_devices(const char *HID,
acpi_walk_callback user_function,
void *context, void **return_value)
{
acpi_status status;
struct acpi_get_devices_info info;
ACPI_FUNCTION_TRACE(acpi_get_devices);
/* Parameter validation */
if (!user_function) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/*
* We're going to call their callback from OUR callback, so we need
* to know what it is, and their context parameter.
*/
info.hid = HID;
info.context = context;
info.user_function = user_function;
/*
* Lock the namespace around the walk.
* The namespace will be unlocked/locked around each call
* to the user function - since this function
* must be allowed to make Acpi calls itself.
*/
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
acpi_ns_get_device_callback, NULL,
&info, return_value);
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_get_devices)
/*******************************************************************************
*
* FUNCTION: acpi_attach_data
*
* PARAMETERS: obj_handle - Namespace node
* handler - Handler for this attachment
* data - Pointer to data to be attached
*
* RETURN: Status
*
* DESCRIPTION: Attach arbitrary data and handler to a namespace node.
*
******************************************************************************/
acpi_status
acpi_attach_data(acpi_handle obj_handle,
acpi_object_handler handler, void *data)
{
struct acpi_namespace_node *node;
acpi_status status;
/* Parameter validation */
if (!obj_handle || !handler || !data) {
return (AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
/* Convert and validate the handle */
node = acpi_ns_validate_handle(obj_handle);
if (!node) {
status = AE_BAD_PARAMETER;
goto unlock_and_exit;
}
status = acpi_ns_attach_data(node, handler, data);
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_attach_data)
/*******************************************************************************
*
* FUNCTION: acpi_detach_data
*
* PARAMETERS: obj_handle - Namespace node handle
* handler - Handler used in call to acpi_attach_data
*
* RETURN: Status
*
* DESCRIPTION: Remove data that was previously attached to a node.
*
******************************************************************************/
acpi_status
acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
{
struct acpi_namespace_node *node;
acpi_status status;
/* Parameter validation */
if (!obj_handle || !handler) {
return (AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
/* Convert and validate the handle */
node = acpi_ns_validate_handle(obj_handle);
if (!node) {
status = AE_BAD_PARAMETER;
goto unlock_and_exit;
}
status = acpi_ns_detach_data(node, handler);
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_detach_data)
/*******************************************************************************
*
* FUNCTION: acpi_get_data
*
* PARAMETERS: obj_handle - Namespace node
* handler - Handler used in call to attach_data
* data - Where the data is returned
*
* RETURN: Status
*
* DESCRIPTION: Retrieve data that was previously attached to a namespace node.
*
******************************************************************************/
acpi_status
acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
{
struct acpi_namespace_node *node;
acpi_status status;
/* Parameter validation */
if (!obj_handle || !handler || !data) {
return (AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
/* Convert and validate the handle */
node = acpi_ns_validate_handle(obj_handle);
if (!node) {
status = AE_BAD_PARAMETER;
goto unlock_and_exit;
}
status = acpi_ns_get_attached_data(node, handler, data);
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_get_data)