drivers/acpi/acpica/tbdata.c

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: tbdata - Table manager data structure functions
 *
 * Copyright (C) 2000 - 2020, Intel Corp.
 *
 *****************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "actables.h"
#include "acevents.h"

#define _COMPONENT          ACPI_TABLES
ACPI_MODULE_NAME("tbdata")

/* Local prototypes */
static acpi_status
acpi_tb_check_duplication(struct acpi_table_desc *table_desc, u32 *table_index);

static u8
acpi_tb_compare_tables(struct acpi_table_desc *table_desc, u32 table_index);

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_compare_tables
 *
 * PARAMETERS:  table_desc          - Table 1 descriptor to be compared
 *              table_index         - Index of table 2 to be compared
 *
 * RETURN:      TRUE if both tables are identical.
 *
 * DESCRIPTION: This function compares a table with another table that has
 *              already been installed in the root table list.
 *
 ******************************************************************************/

static u8
acpi_tb_compare_tables(struct acpi_table_desc *table_desc, u32 table_index)
{
	acpi_status status = AE_OK;
	u8 is_identical;
	struct acpi_table_header *table;
	u32 table_length;
	u8 table_flags;

	status =
	    acpi_tb_acquire_table(&acpi_gbl_root_table_list.tables[table_index],
				  &table, &table_length, &table_flags);
	if (ACPI_FAILURE(status)) {
		return (FALSE);
	}

	/*
	 * Check for a table match on the entire table length,
	 * not just the header.
	 */
	is_identical = (u8)((table_desc->length != table_length ||
			     memcmp(table_desc->pointer, table, table_length)) ?
			    FALSE : TRUE);

	/* Release the acquired table */

	acpi_tb_release_table(table, table_length, table_flags);
	return (is_identical);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_init_table_descriptor
 *
 * PARAMETERS:  table_desc              - Table descriptor
 *              address                 - Physical address of the table
 *              flags                   - Allocation flags of the table
 *              table                   - Pointer to the table
 *
 * RETURN:      None
 *
 * DESCRIPTION: Initialize a new table descriptor
 *
 ******************************************************************************/

void
acpi_tb_init_table_descriptor(struct acpi_table_desc *table_desc,
			      acpi_physical_address address,
			      u8 flags, struct acpi_table_header *table)
{

	/*
	 * Initialize the table descriptor. Set the pointer to NULL, since the
	 * table is not fully mapped at this time.
	 */
	memset(table_desc, 0, sizeof(struct acpi_table_desc));
	table_desc->address = address;
	table_desc->length = table->length;
	table_desc->flags = flags;
	ACPI_MOVE_32_TO_32(table_desc->signature.ascii, table->signature);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_acquire_table
 *
 * PARAMETERS:  table_desc          - Table descriptor
 *              table_ptr           - Where table is returned
 *              table_length        - Where table length is returned
 *              table_flags         - Where table allocation flags are returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Acquire an ACPI table. It can be used for tables not
 *              maintained in the acpi_gbl_root_table_list.
 *
 ******************************************************************************/

acpi_status
acpi_tb_acquire_table(struct acpi_table_desc *table_desc,
		      struct acpi_table_header **table_ptr,
		      u32 *table_length, u8 *table_flags)
{
	struct acpi_table_header *table = NULL;

	switch (table_desc->flags & ACPI_TABLE_ORIGIN_MASK) {
	case ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL:

		table =
		    acpi_os_map_memory(table_desc->address, table_desc->length);
		break;

	case ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL:
	case ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL:

		table = ACPI_CAST_PTR(struct acpi_table_header,
				      ACPI_PHYSADDR_TO_PTR(table_desc->
							   address));
		break;

	default:

		break;
	}

	/* Table is not valid yet */

	if (!table) {
		return (AE_NO_MEMORY);
	}

	/* Fill the return values */

	*table_ptr = table;
	*table_length = table_desc->length;
	*table_flags = table_desc->flags;
	return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_release_table
 *
 * PARAMETERS:  table               - Pointer for the table
 *              table_length        - Length for the table
 *              table_flags         - Allocation flags for the table
 *
 * RETURN:      None
 *
 * DESCRIPTION: Release a table. The inverse of acpi_tb_acquire_table().
 *
 ******************************************************************************/

void
acpi_tb_release_table(struct acpi_table_header *table,
		      u32 table_length, u8 table_flags)
{

	switch (table_flags & ACPI_TABLE_ORIGIN_MASK) {
	case ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL:

		acpi_os_unmap_memory(table, table_length);
		break;

	case ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL:
	case ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL:
	default:

		break;
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_acquire_temp_table
 *
 * PARAMETERS:  table_desc          - Table descriptor to be acquired
 *              address             - Address of the table
 *              flags               - Allocation flags of the table
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function validates the table header to obtain the length
 *              of a table and fills the table descriptor to make its state as
 *              "INSTALLED". Such a table descriptor is only used for verified
 *              installation.
 *
 ******************************************************************************/

acpi_status
acpi_tb_acquire_temp_table(struct acpi_table_desc *table_desc,
			   acpi_physical_address address, u8 flags)
{
	struct acpi_table_header *table_header;

	switch (flags & ACPI_TABLE_ORIGIN_MASK) {
	case ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL:

		/* Get the length of the full table from the header */

		table_header =
		    acpi_os_map_memory(address,
				       sizeof(struct acpi_table_header));
		if (!table_header) {
			return (AE_NO_MEMORY);
		}

		acpi_tb_init_table_descriptor(table_desc, address, flags,
					      table_header);
		acpi_os_unmap_memory(table_header,
				     sizeof(struct acpi_table_header));
		return (AE_OK);

	case ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL:
	case ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL:

		table_header = ACPI_CAST_PTR(struct acpi_table_header,
					     ACPI_PHYSADDR_TO_PTR(address));
		if (!table_header) {
			return (AE_NO_MEMORY);
		}

		acpi_tb_init_table_descriptor(table_desc, address, flags,
					      table_header);
		return (AE_OK);

	default:

		break;
	}

	/* Table is not valid yet */

	return (AE_NO_MEMORY);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_release_temp_table
 *
 * PARAMETERS:  table_desc          - Table descriptor to be released
 *
 * RETURN:      Status
 *
 * DESCRIPTION: The inverse of acpi_tb_acquire_temp_table().
 *
 *****************************************************************************/

void acpi_tb_release_temp_table(struct acpi_table_desc *table_desc)
{

	/*
	 * Note that the .Address is maintained by the callers of
	 * acpi_tb_acquire_temp_table(), thus do not invoke acpi_tb_uninstall_table()
	 * where .Address will be freed.
	 */
	acpi_tb_invalidate_table(table_desc);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_tb_validate_table
 *
 * PARAMETERS:  table_desc          - Table descriptor
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function is called to validate the table, the returned
 *              table descriptor is in "VALIDATED" state.
 *
 *****************************************************************************/

acpi_status acpi_tb_validate_table(struct acpi_table_desc *table_desc)
{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE(tb_validate_table);

	/* Validate the table if necessary */

	if (!table_desc->pointer) {
		status = acpi_tb_acquire_table(table_desc, &table_desc->pointer,
					       &table_desc->length,
					       &table_desc->flags);
		if (!table_desc->pointer) {
			status = AE_NO_MEMORY;
		}
	}

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_invalidate_table
 *
 * PARAMETERS:  table_desc          - Table descriptor
 *
 * RETURN:      None
 *
 * DESCRIPTION: Invalidate one internal ACPI table, this is the inverse of
 *              acpi_tb_validate_table().
 *
 ******************************************************************************/

void acpi_tb_invalidate_table(struct acpi_table_desc *table_desc)
{

	ACPI_FUNCTION_TRACE(tb_invalidate_table);

	/* Table must be validated */

	if (!table_desc->pointer) {
		return_VOID;
	}

	acpi_tb_release_table(table_desc->pointer, table_desc->length,
			      table_desc->flags);
	table_desc->pointer = NULL;

	return_VOID;
}

/******************************************************************************
 *
 * FUNCTION:    acpi_tb_validate_temp_table
 *
 * PARAMETERS:  table_desc          - Table descriptor
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function is called to validate the table, the returned
 *              table descriptor is in "VALIDATED" state.
 *
 *****************************************************************************/

acpi_status acpi_tb_validate_temp_table(struct acpi_table_desc *table_desc)
{

	if (!table_desc->pointer && !acpi_gbl_enable_table_validation) {
		/*
		 * Only validates the header of the table.
		 * Note that Length contains the size of the mapping after invoking
		 * this work around, this value is required by
		 * acpi_tb_release_temp_table().
		 * We can do this because in acpi_init_table_descriptor(), the Length
		 * field of the installed descriptor is filled with the actual
		 * table length obtaining from the table header.
		 */
		table_desc->length = sizeof(struct acpi_table_header);
	}

	return (acpi_tb_validate_table(table_desc));
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_check_duplication
 *
 * PARAMETERS:  table_desc          - Table descriptor
 *              table_index         - Where the table index is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Avoid installing duplicated tables. However table override and
 *              user aided dynamic table load is allowed, thus comparing the
 *              address of the table is not sufficient, and checking the entire
 *              table content is required.
 *
 ******************************************************************************/

static acpi_status
acpi_tb_check_duplication(struct acpi_table_desc *table_desc, u32 *table_index)
{
	u32 i;

	ACPI_FUNCTION_TRACE(tb_check_duplication);

	/* Check if table is already registered */

	for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {

		/* Do not compare with unverified tables */

		if (!
		    (acpi_gbl_root_table_list.tables[i].
		     flags & ACPI_TABLE_IS_VERIFIED)) {
			continue;
		}

		/*
		 * Check for a table match on the entire table length,
		 * not just the header.
		 */
		if (!acpi_tb_compare_tables(table_desc, i)) {
			continue;
		}

		/*
		 * Note: the current mechanism does not unregister a table if it is
		 * dynamically unloaded. The related namespace entries are deleted,
		 * but the table remains in the root table list.
		 *
		 * The assumption here is that the number of different tables that
		 * will be loaded is actually small, and there is minimal overhead
		 * in just keeping the table in case it is needed again.
		 *
		 * If this assumption changes in the future (perhaps on large
		 * machines with many table load/unload operations), tables will
		 * need to be unregistered when they are unloaded, and slots in the
		 * root table list should be reused when empty.
		 */
		if (acpi_gbl_root_table_list.tables[i].flags &
		    ACPI_TABLE_IS_LOADED) {

			/* Table is still loaded, this is an error */

			return_ACPI_STATUS(AE_ALREADY_EXISTS);
		} else {
			*table_index = i;
			return_ACPI_STATUS(AE_CTRL_TERMINATE);
		}
	}

	/* Indicate no duplication to the caller */

	return_ACPI_STATUS(AE_OK);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_tb_verify_temp_table
 *
 * PARAMETERS:  table_desc          - Table descriptor
 *              signature           - Table signature to verify
 *              table_index         - Where the table index is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function is called to validate and verify the table, the
 *              returned table descriptor is in "VALIDATED" state.
 *              Note that 'TableIndex' is required to be set to !NULL to
 *              enable duplication check.
 *
 *****************************************************************************/

acpi_status
acpi_tb_verify_temp_table(struct acpi_table_desc *table_desc,
			  char *signature, u32 *table_index)
{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE(tb_verify_temp_table);

	/* Validate the table */

	status = acpi_tb_validate_temp_table(table_desc);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(AE_NO_MEMORY);
	}

	/* If a particular signature is expected (DSDT/FACS), it must match */

	if (signature &&
	    !ACPI_COMPARE_NAMESEG(&table_desc->signature, signature)) {
		ACPI_BIOS_ERROR((AE_INFO,
				 "Invalid signature 0x%X for ACPI table, expected [%s]",
				 table_desc->signature.integer, signature));
		status = AE_BAD_SIGNATURE;
		goto invalidate_and_exit;
	}

	if (acpi_gbl_enable_table_validation) {

		/* Verify the checksum */

		status =
		    acpi_tb_verify_checksum(table_desc->pointer,
					    table_desc->length);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY,
					"%4.4s 0x%8.8X%8.8X"
					" Attempted table install failed",
					acpi_ut_valid_nameseg(table_desc->
							      signature.
							      ascii) ?
					table_desc->signature.ascii : "????",
					ACPI_FORMAT_UINT64(table_desc->
							   address)));

			goto invalidate_and_exit;
		}

		/* Avoid duplications */

		if (table_index) {
			status =
			    acpi_tb_check_duplication(table_desc, table_index);
			if (ACPI_FAILURE(status)) {
				if (status != AE_CTRL_TERMINATE) {
					ACPI_EXCEPTION((AE_INFO, status,
							"%4.4s 0x%8.8X%8.8X"
							" Table is already loaded",
							acpi_ut_valid_nameseg
							(table_desc->signature.
							 ascii) ? table_desc->
							signature.
							ascii : "????",
							ACPI_FORMAT_UINT64
							(table_desc->address)));
				}

				goto invalidate_and_exit;
			}
		}

		table_desc->flags |= ACPI_TABLE_IS_VERIFIED;
	}

	return_ACPI_STATUS(status);

invalidate_and_exit:
	acpi_tb_invalidate_table(table_desc);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_resize_root_table_list
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Expand the size of global table array
 *
 ******************************************************************************/

acpi_status acpi_tb_resize_root_table_list(void)
{
	struct acpi_table_desc *tables;
	u32 table_count;
	u32 current_table_count, max_table_count;
	u32 i;

	ACPI_FUNCTION_TRACE(tb_resize_root_table_list);

	/* allow_resize flag is a parameter to acpi_initialize_tables */

	if (!(acpi_gbl_root_table_list.flags & ACPI_ROOT_ALLOW_RESIZE)) {
		ACPI_ERROR((AE_INFO,
			    "Resize of Root Table Array is not allowed"));
		return_ACPI_STATUS(AE_SUPPORT);
	}

	/* Increase the Table Array size */

	if (acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) {
		table_count = acpi_gbl_root_table_list.max_table_count;
	} else {
		table_count = acpi_gbl_root_table_list.current_table_count;
	}

	max_table_count = table_count + ACPI_ROOT_TABLE_SIZE_INCREMENT;
	tables = ACPI_ALLOCATE_ZEROED(((acpi_size)max_table_count) *
				      sizeof(struct acpi_table_desc));
	if (!tables) {
		ACPI_ERROR((AE_INFO,
			    "Could not allocate new root table array"));
		return_ACPI_STATUS(AE_NO_MEMORY);
	}

	/* Copy and free the previous table array */

	current_table_count = 0;
	if (acpi_gbl_root_table_list.tables) {
		for (i = 0; i < table_count; i++) {
			if (acpi_gbl_root_table_list.tables[i].address) {
				memcpy(tables + current_table_count,
				       acpi_gbl_root_table_list.tables + i,
				       sizeof(struct acpi_table_desc));
				current_table_count++;
			}
		}

		if (acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) {
			ACPI_FREE(acpi_gbl_root_table_list.tables);
		}
	}

	acpi_gbl_root_table_list.tables = tables;
	acpi_gbl_root_table_list.max_table_count = max_table_count;
	acpi_gbl_root_table_list.current_table_count = current_table_count;
	acpi_gbl_root_table_list.flags |= ACPI_ROOT_ORIGIN_ALLOCATED;

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_get_next_table_descriptor
 *
 * PARAMETERS:  table_index         - Where table index is returned
 *              table_desc          - Where table descriptor is returned
 *
 * RETURN:      Status and table index/descriptor.
 *
 * DESCRIPTION: Allocate a new ACPI table entry to the global table list
 *
 ******************************************************************************/

acpi_status
acpi_tb_get_next_table_descriptor(u32 *table_index,
				  struct acpi_table_desc **table_desc)
{
	acpi_status status;
	u32 i;

	/* Ensure that there is room for the table in the Root Table List */

	if (acpi_gbl_root_table_list.current_table_count >=
	    acpi_gbl_root_table_list.max_table_count) {
		status = acpi_tb_resize_root_table_list();
		if (ACPI_FAILURE(status)) {
			return (status);
		}
	}

	i = acpi_gbl_root_table_list.current_table_count;
	acpi_gbl_root_table_list.current_table_count++;

	if (table_index) {
		*table_index = i;
	}
	if (table_desc) {
		*table_desc = &acpi_gbl_root_table_list.tables[i];
	}

	return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_terminate
 *
 * PARAMETERS:  None
 *
 * RETURN:      None
 *
 * DESCRIPTION: Delete all internal ACPI tables
 *
 ******************************************************************************/

void acpi_tb_terminate(void)
{
	u32 i;

	ACPI_FUNCTION_TRACE(tb_terminate);

	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);

	/* Delete the individual tables */

	for (i = 0; i < acpi_gbl_root_table_list.current_table_count; i++) {
		acpi_tb_uninstall_table(&acpi_gbl_root_table_list.tables[i]);
	}

	/*
	 * Delete the root table array if allocated locally. Array cannot be
	 * mapped, so we don't need to check for that flag.
	 */
	if (acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) {
		ACPI_FREE(acpi_gbl_root_table_list.tables);
	}

	acpi_gbl_root_table_list.tables = NULL;
	acpi_gbl_root_table_list.flags = 0;
	acpi_gbl_root_table_list.current_table_count = 0;

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "ACPI Tables freed\n"));

	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
	return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_delete_namespace_by_owner
 *
 * PARAMETERS:  table_index         - Table index
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Delete all namespace objects created when this table was loaded.
 *
 ******************************************************************************/

acpi_status acpi_tb_delete_namespace_by_owner(u32 table_index)
{
	acpi_owner_id owner_id;
	acpi_status status;

	ACPI_FUNCTION_TRACE(tb_delete_namespace_by_owner);

	status = acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	if (table_index >= acpi_gbl_root_table_list.current_table_count) {

		/* The table index does not exist */

		(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
		return_ACPI_STATUS(AE_NOT_EXIST);
	}

	/* Get the owner ID for this table, used to delete namespace nodes */

	owner_id = acpi_gbl_root_table_list.tables[table_index].owner_id;
	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);

	/*
	 * Need to acquire the namespace writer lock to prevent interference
	 * with any concurrent namespace walks. The interpreter must be
	 * released during the deletion since the acquisition of the deletion
	 * lock may block, and also since the execution of a namespace walk
	 * must be allowed to use the interpreter.
	 */
	status = acpi_ut_acquire_write_lock(&acpi_gbl_namespace_rw_lock);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	acpi_ns_delete_namespace_by_owner(owner_id);
	acpi_ut_release_write_lock(&acpi_gbl_namespace_rw_lock);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_allocate_owner_id
 *
 * PARAMETERS:  table_index         - Table index
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Allocates owner_id in table_desc
 *
 ******************************************************************************/

acpi_status acpi_tb_allocate_owner_id(u32 table_index)
{
	acpi_status status = AE_BAD_PARAMETER;

	ACPI_FUNCTION_TRACE(tb_allocate_owner_id);

	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
	if (table_index < acpi_gbl_root_table_list.current_table_count) {
		status =
		    acpi_ut_allocate_owner_id(&
					      (acpi_gbl_root_table_list.
					       tables[table_index].owner_id));
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_release_owner_id
 *
 * PARAMETERS:  table_index         - Table index
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Releases owner_id in table_desc
 *
 ******************************************************************************/

acpi_status acpi_tb_release_owner_id(u32 table_index)
{
	acpi_status status = AE_BAD_PARAMETER;

	ACPI_FUNCTION_TRACE(tb_release_owner_id);

	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
	if (table_index < acpi_gbl_root_table_list.current_table_count) {
		acpi_ut_release_owner_id(&
					 (acpi_gbl_root_table_list.
					  tables[table_index].owner_id));
		status = AE_OK;
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_get_owner_id
 *
 * PARAMETERS:  table_index         - Table index
 *              owner_id            - Where the table owner_id is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: returns owner_id for the ACPI table
 *
 ******************************************************************************/

acpi_status acpi_tb_get_owner_id(u32 table_index, acpi_owner_id *owner_id)
{
	acpi_status status = AE_BAD_PARAMETER;

	ACPI_FUNCTION_TRACE(tb_get_owner_id);

	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
	if (table_index < acpi_gbl_root_table_list.current_table_count) {
		*owner_id =
		    acpi_gbl_root_table_list.tables[table_index].owner_id;
		status = AE_OK;
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_is_table_loaded
 *
 * PARAMETERS:  table_index         - Index into the root table
 *
 * RETURN:      Table Loaded Flag
 *
 ******************************************************************************/

u8 acpi_tb_is_table_loaded(u32 table_index)
{
	u8 is_loaded = FALSE;

	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
	if (table_index < acpi_gbl_root_table_list.current_table_count) {
		is_loaded = (u8)
		    (acpi_gbl_root_table_list.tables[table_index].flags &
		     ACPI_TABLE_IS_LOADED);
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
	return (is_loaded);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_set_table_loaded_flag
 *
 * PARAMETERS:  table_index         - Table index
 *              is_loaded           - TRUE if table is loaded, FALSE otherwise
 *
 * RETURN:      None
 *
 * DESCRIPTION: Sets the table loaded flag to either TRUE or FALSE.
 *
 ******************************************************************************/

void acpi_tb_set_table_loaded_flag(u32 table_index, u8 is_loaded)
{

	(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
	if (table_index < acpi_gbl_root_table_list.current_table_count) {
		if (is_loaded) {
			acpi_gbl_root_table_list.tables[table_index].flags |=
			    ACPI_TABLE_IS_LOADED;
		} else {
			acpi_gbl_root_table_list.tables[table_index].flags &=
			    ~ACPI_TABLE_IS_LOADED;
		}
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_load_table
 *
 * PARAMETERS:  table_index             - Table index
 *              parent_node             - Where table index is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Load an ACPI table
 *
 ******************************************************************************/

acpi_status
acpi_tb_load_table(u32 table_index, struct acpi_namespace_node *parent_node)
{
	struct acpi_table_header *table;
	acpi_status status;
	acpi_owner_id owner_id;

	ACPI_FUNCTION_TRACE(tb_load_table);

	/*
	 * Note: Now table is "INSTALLED", it must be validated before
	 * using.
	 */
	status = acpi_get_table_by_index(table_index, &table);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	status = acpi_ns_load_table(table_index, parent_node);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/*
	 * Update GPEs for any new _Lxx/_Exx methods. Ignore errors. The host is
	 * responsible for discovering any new wake GPEs by running _PRW methods
	 * that may have been loaded by this table.
	 */
	status = acpi_tb_get_owner_id(table_index, &owner_id);
	if (ACPI_SUCCESS(status)) {
		acpi_ev_update_gpes(owner_id);
	}

	/* Invoke table handler */

	acpi_tb_notify_table(ACPI_TABLE_EVENT_LOAD, table);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_install_and_load_table
 *
 * PARAMETERS:  address                 - Physical address of the table
 *              flags                   - Allocation flags of the table
 *              override                - Whether override should be performed
 *              table_index             - Where table index is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install and load an ACPI table
 *
 ******************************************************************************/

acpi_status
acpi_tb_install_and_load_table(acpi_physical_address address,
			       u8 flags, u8 override, u32 *table_index)
{
	acpi_status status;
	u32 i;

	ACPI_FUNCTION_TRACE(tb_install_and_load_table);

	/* Install the table and load it into the namespace */

	status = acpi_tb_install_standard_table(address, flags, TRUE,
						override, &i);
	if (ACPI_FAILURE(status)) {
		goto exit;
	}

	status = acpi_tb_load_table(i, acpi_gbl_root_node);

exit:
	*table_index = i;
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_tb_install_and_load_table)

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_unload_table
 *
 * PARAMETERS:  table_index             - Table index
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Unload an ACPI table
 *
 ******************************************************************************/

acpi_status acpi_tb_unload_table(u32 table_index)
{
	acpi_status status = AE_OK;
	struct acpi_table_header *table;

	ACPI_FUNCTION_TRACE(tb_unload_table);

	/* Ensure the table is still loaded */

	if (!acpi_tb_is_table_loaded(table_index)) {
		return_ACPI_STATUS(AE_NOT_EXIST);
	}

	/* Invoke table handler */

	status = acpi_get_table_by_index(table_index, &table);
	if (ACPI_SUCCESS(status)) {
		acpi_tb_notify_table(ACPI_TABLE_EVENT_UNLOAD, table);
	}

	/* Delete the portion of the namespace owned by this table */

	status = acpi_tb_delete_namespace_by_owner(table_index);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	(void)acpi_tb_release_owner_id(table_index);
	acpi_tb_set_table_loaded_flag(table_index, FALSE);
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_tb_unload_table)

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_notify_table
 *
 * PARAMETERS:  event               - Table event
 *              table               - Validated table pointer
 *
 * RETURN:      None
 *
 * DESCRIPTION: Notify a table event to the users.
 *
 ******************************************************************************/

void acpi_tb_notify_table(u32 event, void *table)
{
	/* Invoke table handler if present */

	if (acpi_gbl_table_handler) {
		(void)acpi_gbl_table_handler(event, table,
					     acpi_gbl_table_handler_context);
	}
}