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linux-next/drivers/acpi/acpica/tbxface.c

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/******************************************************************************
*
* Module Name: tbxface - ACPI table-oriented external interfaces
*
*****************************************************************************/
/*
* 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.
*/
#define EXPORT_ACPI_INTERFACES
#include <acpi/acpi.h>
#include "accommon.h"
#include "actables.h"
#define _COMPONENT ACPI_TABLES
ACPI_MODULE_NAME("tbxface")
/*******************************************************************************
*
* FUNCTION: acpi_allocate_root_table
*
* PARAMETERS: initial_table_count - Size of initial_table_array, in number of
* struct acpi_table_desc structures
*
* RETURN: Status
*
* DESCRIPTION: Allocate a root table array. Used by iASL compiler and
* acpi_initialize_tables.
*
******************************************************************************/
acpi_status acpi_allocate_root_table(u32 initial_table_count)
{
acpi_gbl_root_table_list.max_table_count = initial_table_count;
acpi_gbl_root_table_list.flags = ACPI_ROOT_ALLOW_RESIZE;
return (acpi_tb_resize_root_table_list());
}
/*******************************************************************************
*
* FUNCTION: acpi_initialize_tables
*
* PARAMETERS: initial_table_array - Pointer to an array of pre-allocated
* struct acpi_table_desc structures. If NULL, the
* array is dynamically allocated.
* initial_table_count - Size of initial_table_array, in number of
* struct acpi_table_desc structures
* allow_resize - Flag to tell Table Manager if resize of
* pre-allocated array is allowed. Ignored
* if initial_table_array is NULL.
*
* RETURN: Status
*
* DESCRIPTION: Initialize the table manager, get the RSDP and RSDT/XSDT.
*
* NOTE: Allows static allocation of the initial table array in order
* to avoid the use of dynamic memory in confined environments
* such as the kernel boot sequence where it may not be available.
*
* If the host OS memory managers are initialized, use NULL for
* initial_table_array, and the table will be dynamically allocated.
*
******************************************************************************/
acpi_status __init
acpi_initialize_tables(struct acpi_table_desc * initial_table_array,
u32 initial_table_count, u8 allow_resize)
{
acpi_physical_address rsdp_address;
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_initialize_tables);
/*
* Setup the Root Table Array and allocate the table array
* if requested
*/
if (!initial_table_array) {
status = acpi_allocate_root_table(initial_table_count);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
} else {
/* Root Table Array has been statically allocated by the host */
ACPI_MEMSET(initial_table_array, 0,
(acpi_size) initial_table_count *
sizeof(struct acpi_table_desc));
acpi_gbl_root_table_list.tables = initial_table_array;
acpi_gbl_root_table_list.max_table_count = initial_table_count;
acpi_gbl_root_table_list.flags = ACPI_ROOT_ORIGIN_UNKNOWN;
if (allow_resize) {
acpi_gbl_root_table_list.flags |=
ACPI_ROOT_ALLOW_RESIZE;
}
}
/* Get the address of the RSDP */
rsdp_address = acpi_os_get_root_pointer();
if (!rsdp_address) {
return_ACPI_STATUS(AE_NOT_FOUND);
}
/*
* Get the root table (RSDT or XSDT) and extract all entries to the local
* Root Table Array. This array contains the information of the RSDT/XSDT
* in a common, more useable format.
*/
status = acpi_tb_parse_root_table(rsdp_address);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL_INIT(acpi_initialize_tables)
/*******************************************************************************
*
* FUNCTION: acpi_reallocate_root_table
*
* PARAMETERS: None
*
* RETURN: Status
*
* DESCRIPTION: Reallocate Root Table List into dynamic memory. Copies the
* root list from the previously provided scratch area. Should
* be called once dynamic memory allocation is available in the
* kernel.
*
******************************************************************************/
acpi_status __init acpi_reallocate_root_table(void)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_reallocate_root_table);
/*
* Only reallocate the root table if the host provided a static buffer
* for the table array in the call to acpi_initialize_tables.
*/
if (acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) {
return_ACPI_STATUS(AE_SUPPORT);
}
acpi_gbl_root_table_list.flags |= ACPI_ROOT_ALLOW_RESIZE;
status = acpi_tb_resize_root_table_list();
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL_INIT(acpi_reallocate_root_table)
/*******************************************************************************
*
* FUNCTION: acpi_get_table_header
*
* PARAMETERS: signature - ACPI signature of needed table
* instance - Which instance (for SSDTs)
* out_table_header - The pointer to the table header to fill
*
* RETURN: Status and pointer to mapped table header
*
* DESCRIPTION: Finds an ACPI table header.
*
* NOTE: Caller is responsible in unmapping the header with
* acpi_os_unmap_memory
*
******************************************************************************/
acpi_status
acpi_get_table_header(char *signature,
u32 instance, struct acpi_table_header *out_table_header)
{
u32 i;
u32 j;
struct acpi_table_header *header;
/* Parameter validation */
if (!signature || !out_table_header) {
return (AE_BAD_PARAMETER);
}
/* Walk the root table list */
for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
i++) {
if (!ACPI_COMPARE_NAME
(&(acpi_gbl_root_table_list.tables[i].signature),
signature)) {
continue;
}
if (++j < instance) {
continue;
}
if (!acpi_gbl_root_table_list.tables[i].pointer) {
if ((acpi_gbl_root_table_list.tables[i].flags &
ACPI_TABLE_ORIGIN_MASK) ==
ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL) {
header =
acpi_os_map_memory(acpi_gbl_root_table_list.
tables[i].address,
sizeof(struct
acpi_table_header));
if (!header) {
return (AE_NO_MEMORY);
}
ACPI_MEMCPY(out_table_header, header,
sizeof(struct acpi_table_header));
acpi_os_unmap_memory(header,
sizeof(struct
acpi_table_header));
} else {
return (AE_NOT_FOUND);
}
} else {
ACPI_MEMCPY(out_table_header,
acpi_gbl_root_table_list.tables[i].pointer,
sizeof(struct acpi_table_header));
}
return (AE_OK);
}
return (AE_NOT_FOUND);
}
ACPI_EXPORT_SYMBOL(acpi_get_table_header)
/*******************************************************************************
*
* FUNCTION: acpi_get_table_with_size
*
* PARAMETERS: signature - ACPI signature of needed table
* instance - Which instance (for SSDTs)
* out_table - Where the pointer to the table is returned
*
* RETURN: Status and pointer to the requested table
*
* DESCRIPTION: Finds and verifies an ACPI table. Table must be in the
* RSDT/XSDT.
*
******************************************************************************/
acpi_status
acpi_get_table_with_size(char *signature,
u32 instance, struct acpi_table_header **out_table,
acpi_size *tbl_size)
{
u32 i;
u32 j;
acpi_status status;
/* Parameter validation */
if (!signature || !out_table) {
return (AE_BAD_PARAMETER);
}
/* Walk the root table list */
for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
i++) {
if (!ACPI_COMPARE_NAME
(&(acpi_gbl_root_table_list.tables[i].signature),
signature)) {
continue;
}
if (++j < instance) {
continue;
}
status =
ACPICA: Tables: Clean up split INSTALLED/VALIDATED table state logics. This patch is mainly a naming cleanup to clarify hidden logics, no functional changes. acpi_initialize_tables() is used by Linux to install table addresses for early boot steps. During this stage, table addresses are mapped by early_ioremap() mechanism which is different from the runtime IO mappings. Thus it is not safe for ACPICA to keep mapped pointers in struct acpi_table_desc structure during this stage. In order to support this in ACPICA, table states are divided into 1. "INSTALLED" (where struct acpi_table_desc.Pointer is always NULL) and 2. "VALIDATED" (where struct acpi_table_desc.Pointer is always not NULL). During acpi_initialize_tables(), table state are ensured to be "INSTALLED" but not "VALIDATED". This logic is ensured by the original code in very ambigious way. For example, currently acpi_tb_delete_table() is invoked in some place to perform an uninstallation while it is invoked in other place to perform an invalidation. They happen to work just because no one enters the penalty where the 2 behaviours are not equivalent. The naming cleanups are made in this patch: A. For installation and validation: There is code setting struct acpi_table_desc.Pointer first and delete it immediately to keep the descriptor's state as "INSTALLED" during the installation. This patch implements this in more direct way. After applying it, struct acpi_table_desc.Pointer will never be set in acpi_tb_install_table() and acpi_tb_override_table() as they are the only functions invoked during acpi_initialize_tables(). This is achieved by: 1. Rename acpi_tb_verify_table() to acpi_tb_validate_table() to clarify this change. 2. Rename acpi_tb_table_override() to acpi_tb_override_table() to keep nameing consistencies as other APIs (verb. Table). 3. Stops setting struct acpi_table_desc.Pointer in acpi_tb_install_table() and acpi_tb_table_override(). 4. Introduce acpi_tb_acquire_table() to acquire the table pointer that is not maintained in the struct acpi_table_desc of the global root table list and rewrite acpi_tb_validate_table() using this new function to reduce redundancies. 5. Replace the table pointer using the overridden table pointer in acpi_tb_add_table(). As acpi_tb_add_table() is not invoked during early boot stage, tables returned from this functions should be "VALIDATED". As acpi_tb_override_table() is modified by this patch to return a "INSTALLED" but not "VALIDATED" descriptor, to keep acpi_tb_add_table() unchanged, struct acpi_table_desc.Pointer is filled in acpi_tb_add_table(). B. For invalidation and uninstallation: The original code invalidate table by invoking acpi_tb_delete_table() here and there, but actually this function should only be used to uninstall tables. This can work just because its invocations are equivalent to invalidation in some cases. This patch splits acpi_tb_delete_table() into acpi_tb_invalidate_table() and acpi_tb_uninstall_table() and cleans up the hidden logic using the new APIs. This is achieved by: 1. Rename acpi_tb_delete_table() to acpi_tb_uninstall_table() as it is mainly called before resetting struct acpi_table_desc.Address. Thus the table descriptor is in "not INSTALLED" state. This patch enforces this by setting struct acpi_table_desc.Address to NULL in this function. 2. Introduce acpi_tb_invalidate_table() to be the reversal of acpi_tb_validate_table() and invoke it in acpi_tb_uninstall_table(). 3. Introduce acpi_tb_release_table() to release the table pointer that is not maintained in acpi_gbl_root_table_list and rewrite acpi_tb_invalidate_table() using this new function to reduce redundancies. After cleaning up, the maintainability of the internal APIs are also improved: 1. acpi_tb_acquire_table: Acquire struct acpi_table_header according to ACPI_TABLE_ORIGIN_xxx flags. 2. acpi_tb_release_table: Release struct acpi_table_header according to ACPI_TABLE_ORIGIN_xxx flags. 3. acpi_tb_install_table: Make struct acpi_table_desc.Address not NULL according to ACPI_TABLE_ORIGIN_xxx flags. 4. acpi_tb_uninstall_table: Make struct acpi_table_desc.Address NULL according to ACPI_TABLE_ORIGIN_xxx flags. 5. acpi_tb_validate_table: Make struct acpi_table_desc.Pointer not NULL according to ACPI_TABLE_ORIGIN_xxx flags. 6. acpi_tb_invalidate_table: Make struct acpi_table_desc.Pointer NULL according to ACPI_TABLE_ORIGIN_xxx flags. 7. acpi_tb_override_table: Replace struct acpi_table_desc.Address and struct acpi_table_desc.Flags. It only happens in "INSTALLED" state. The patch has been unit tested in acpi_exec by: 1. Initializing; 2. Executing exc_tbl ASLTS tests; 3. Executing "Load" command. So that all original acpi_tb_install_table() and acpi_tb_override_table() invocations are covered. Known Issues: 1. Cleanup acpi_tb_add_table() to Kill Code Redundancies Current implementation in acpi_tb_add_table() is not very clean, further patch can rewrite acpi_tb_add_table() with ordered acpi_tb_install_table(), acpi_tb_override_table() and acpi_tb_validate_table(). It is not done in this patch so that it is easy for the reviewers to understand the changes in this patch. Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-04 12:38:42 +08:00
acpi_tb_validate_table(&acpi_gbl_root_table_list.tables[i]);
if (ACPI_SUCCESS(status)) {
*out_table = acpi_gbl_root_table_list.tables[i].pointer;
*tbl_size = acpi_gbl_root_table_list.tables[i].length;
}
ACPI: ACPICA 20060707 Added the ACPI_PACKED_POINTERS_NOT_SUPPORTED macro to support C compilers that do not allow the initialization of address pointers within packed structures - even though the hardware itself may support misaligned transfers. Some of the debug data structures are packed by default to minimize size. Added an error message for the case where acpi_os_get_thread_id() returns zero. A non-zero value is required by the core ACPICA code to ensure the proper operation of AML mutexes and recursive control methods. The DSDT is now the only ACPI table that determines whether the AML interpreter is in 32-bit or 64-bit mode. Not really a functional change, but the hooks for per-table 32/64 switching have been removed from the code. A clarification to the ACPI specification is forthcoming in ACPI 3.0B. Fixed a possible leak of an Owner ID in the error path of tbinstal.c acpi_tb_init_table_descriptor() and migrated all table OwnerID deletion to a single place in acpi_tb_uninstall_table() to correct possible leaks when using the acpi_tb_delete_tables_by_type() interface (with assistance from Lance Ortiz.) Fixed a problem with Serialized control methods where the semaphore associated with the method could be over-signaled after multiple method invocations. Fixed two issues with the locking of the internal namespace data structure. Both the Unload() operator and acpi_unload_table() interface now lock the namespace during the namespace deletion associated with the table unload (with assistance from Linn Crosetto.) Fixed problem reports (Valery Podrezov) integrated: - Eliminate unnecessary memory allocation for CreateXxxxField http://bugzilla.kernel.org/show_bug.cgi?id=5426 Fixed problem reports (Fiodor Suietov) integrated: - Incomplete cleanup branches in AcpiTbGetTableRsdt (BZ 369) - On Address Space handler deletion, needless deactivation call (BZ 374) - AcpiRemoveAddressSpaceHandler: validate Device handle parameter (BZ 375) - Possible memory leak, Notify sub-objects of Processor, Power, ThermalZone (BZ 376) - AcpiRemoveAddressSpaceHandler: validate Handler parameter (BZ 378) - Minimum Length of RSDT should be validated (BZ 379) - AcpiRemoveNotifyHandler: return AE_NOT_EXIST if Processor Obj has no Handler (BZ (380) - AcpiUnloadTable: return AE_NOT_EXIST if no table of specified type loaded (BZ 381) Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-07-08 08:44:38 +08:00
if (!acpi_gbl_permanent_mmap) {
acpi_gbl_root_table_list.tables[i].pointer = NULL;
}
return (status);
}
return (AE_NOT_FOUND);
}
ACPI_EXPORT_SYMBOL(acpi_get_table_with_size)
acpi_status
acpi_get_table(char *signature,
u32 instance, struct acpi_table_header **out_table)
{
acpi_size tbl_size;
return acpi_get_table_with_size(signature,
instance, out_table, &tbl_size);
}
ACPI_EXPORT_SYMBOL(acpi_get_table)
/*******************************************************************************
*
* FUNCTION: acpi_get_table_by_index
*
* PARAMETERS: table_index - Table index
* table - Where the pointer to the table is returned
*
* RETURN: Status and pointer to the requested table
*
* DESCRIPTION: Obtain a table by an index into the global table list. Used
* internally also.
*
******************************************************************************/
acpi_status
acpi_get_table_by_index(u32 table_index, struct acpi_table_header ** table)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_get_table_by_index);
/* Parameter validation */
if (!table) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
/* Validate index */
if (table_index >= acpi_gbl_root_table_list.current_table_count) {
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
if (!acpi_gbl_root_table_list.tables[table_index].pointer) {
/* Table is not mapped, map it */
status =
ACPICA: Tables: Clean up split INSTALLED/VALIDATED table state logics. This patch is mainly a naming cleanup to clarify hidden logics, no functional changes. acpi_initialize_tables() is used by Linux to install table addresses for early boot steps. During this stage, table addresses are mapped by early_ioremap() mechanism which is different from the runtime IO mappings. Thus it is not safe for ACPICA to keep mapped pointers in struct acpi_table_desc structure during this stage. In order to support this in ACPICA, table states are divided into 1. "INSTALLED" (where struct acpi_table_desc.Pointer is always NULL) and 2. "VALIDATED" (where struct acpi_table_desc.Pointer is always not NULL). During acpi_initialize_tables(), table state are ensured to be "INSTALLED" but not "VALIDATED". This logic is ensured by the original code in very ambigious way. For example, currently acpi_tb_delete_table() is invoked in some place to perform an uninstallation while it is invoked in other place to perform an invalidation. They happen to work just because no one enters the penalty where the 2 behaviours are not equivalent. The naming cleanups are made in this patch: A. For installation and validation: There is code setting struct acpi_table_desc.Pointer first and delete it immediately to keep the descriptor's state as "INSTALLED" during the installation. This patch implements this in more direct way. After applying it, struct acpi_table_desc.Pointer will never be set in acpi_tb_install_table() and acpi_tb_override_table() as they are the only functions invoked during acpi_initialize_tables(). This is achieved by: 1. Rename acpi_tb_verify_table() to acpi_tb_validate_table() to clarify this change. 2. Rename acpi_tb_table_override() to acpi_tb_override_table() to keep nameing consistencies as other APIs (verb. Table). 3. Stops setting struct acpi_table_desc.Pointer in acpi_tb_install_table() and acpi_tb_table_override(). 4. Introduce acpi_tb_acquire_table() to acquire the table pointer that is not maintained in the struct acpi_table_desc of the global root table list and rewrite acpi_tb_validate_table() using this new function to reduce redundancies. 5. Replace the table pointer using the overridden table pointer in acpi_tb_add_table(). As acpi_tb_add_table() is not invoked during early boot stage, tables returned from this functions should be "VALIDATED". As acpi_tb_override_table() is modified by this patch to return a "INSTALLED" but not "VALIDATED" descriptor, to keep acpi_tb_add_table() unchanged, struct acpi_table_desc.Pointer is filled in acpi_tb_add_table(). B. For invalidation and uninstallation: The original code invalidate table by invoking acpi_tb_delete_table() here and there, but actually this function should only be used to uninstall tables. This can work just because its invocations are equivalent to invalidation in some cases. This patch splits acpi_tb_delete_table() into acpi_tb_invalidate_table() and acpi_tb_uninstall_table() and cleans up the hidden logic using the new APIs. This is achieved by: 1. Rename acpi_tb_delete_table() to acpi_tb_uninstall_table() as it is mainly called before resetting struct acpi_table_desc.Address. Thus the table descriptor is in "not INSTALLED" state. This patch enforces this by setting struct acpi_table_desc.Address to NULL in this function. 2. Introduce acpi_tb_invalidate_table() to be the reversal of acpi_tb_validate_table() and invoke it in acpi_tb_uninstall_table(). 3. Introduce acpi_tb_release_table() to release the table pointer that is not maintained in acpi_gbl_root_table_list and rewrite acpi_tb_invalidate_table() using this new function to reduce redundancies. After cleaning up, the maintainability of the internal APIs are also improved: 1. acpi_tb_acquire_table: Acquire struct acpi_table_header according to ACPI_TABLE_ORIGIN_xxx flags. 2. acpi_tb_release_table: Release struct acpi_table_header according to ACPI_TABLE_ORIGIN_xxx flags. 3. acpi_tb_install_table: Make struct acpi_table_desc.Address not NULL according to ACPI_TABLE_ORIGIN_xxx flags. 4. acpi_tb_uninstall_table: Make struct acpi_table_desc.Address NULL according to ACPI_TABLE_ORIGIN_xxx flags. 5. acpi_tb_validate_table: Make struct acpi_table_desc.Pointer not NULL according to ACPI_TABLE_ORIGIN_xxx flags. 6. acpi_tb_invalidate_table: Make struct acpi_table_desc.Pointer NULL according to ACPI_TABLE_ORIGIN_xxx flags. 7. acpi_tb_override_table: Replace struct acpi_table_desc.Address and struct acpi_table_desc.Flags. It only happens in "INSTALLED" state. The patch has been unit tested in acpi_exec by: 1. Initializing; 2. Executing exc_tbl ASLTS tests; 3. Executing "Load" command. So that all original acpi_tb_install_table() and acpi_tb_override_table() invocations are covered. Known Issues: 1. Cleanup acpi_tb_add_table() to Kill Code Redundancies Current implementation in acpi_tb_add_table() is not very clean, further patch can rewrite acpi_tb_add_table() with ordered acpi_tb_install_table(), acpi_tb_override_table() and acpi_tb_validate_table(). It is not done in this patch so that it is easy for the reviewers to understand the changes in this patch. Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-04 12:38:42 +08:00
acpi_tb_validate_table(&acpi_gbl_root_table_list.
tables[table_index]);
if (ACPI_FAILURE(status)) {
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return_ACPI_STATUS(status);
}
}
*table = acpi_gbl_root_table_list.tables[table_index].pointer;
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return_ACPI_STATUS(AE_OK);
}
ACPI_EXPORT_SYMBOL(acpi_get_table_by_index)
/*******************************************************************************
*
* FUNCTION: acpi_install_table_handler
*
* PARAMETERS: handler - Table event handler
* context - Value passed to the handler on each event
*
* RETURN: Status
*
* DESCRIPTION: Install a global table event handler.
*
******************************************************************************/
acpi_status
acpi_install_table_handler(acpi_table_handler handler, void *context)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_install_table_handler);
if (!handler) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Don't allow more than one handler */
if (acpi_gbl_table_handler) {
status = AE_ALREADY_EXISTS;
goto cleanup;
}
/* Install the handler */
acpi_gbl_table_handler = handler;
acpi_gbl_table_handler_context = context;
cleanup:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_install_table_handler)
/*******************************************************************************
*
* FUNCTION: acpi_remove_table_handler
*
* PARAMETERS: handler - Table event handler that was installed
* previously.
*
* RETURN: Status
*
* DESCRIPTION: Remove a table event handler
*
******************************************************************************/
acpi_status acpi_remove_table_handler(acpi_table_handler handler)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_remove_table_handler);
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Make sure that the installed handler is the same */
if (!handler || handler != acpi_gbl_table_handler) {
status = AE_BAD_PARAMETER;
goto cleanup;
}
/* Remove the handler */
acpi_gbl_table_handler = NULL;
cleanup:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_remove_table_handler)