ACPICA: Invalidate DdbHandle after table unload

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / acpica / exconfig.c

/******************************************************************************
 *
 * Module Name: exconfig - Namespace reconfiguration (Load/Unload opcodes)
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2008, 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 "acinterp.h"
#include "acnamesp.h"
#include "actables.h"
#include "acdispat.h"

#define _COMPONENT          ACPI_EXECUTER
ACPI_MODULE_NAME("exconfig")

/* Local prototypes */
static acpi_status
acpi_ex_add_table(u32 table_index,
                  struct acpi_namespace_node *parent_node,
                  union acpi_operand_object **ddb_handle);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_add_table
 *
 * PARAMETERS:  Table               - Pointer to raw table
 *              parent_node         - Where to load the table (scope)
 *              ddb_handle          - Where to return the table handle.
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Common function to Install and Load an ACPI table with a
 *              returned table handle.
 *
 ******************************************************************************/

static acpi_status
acpi_ex_add_table(u32 table_index,
                  struct acpi_namespace_node *parent_node,
                  union acpi_operand_object **ddb_handle)
{
        acpi_status status;
        union acpi_operand_object *obj_desc;

        ACPI_FUNCTION_TRACE(ex_add_table);

        /* Create an object to be the table handle */

        obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_REFERENCE);
        if (!obj_desc) {
                return_ACPI_STATUS(AE_NO_MEMORY);
        }

        /* Init the table handle */

        obj_desc->common.flags |= AOPOBJ_DATA_VALID;
        obj_desc->reference.class = ACPI_REFCLASS_TABLE;
        *ddb_handle = obj_desc;

        /* Install the new table into the local data structures */

        obj_desc->reference.value = table_index;

        /* Add the table to the namespace */

        status = acpi_ns_load_table(table_index, parent_node);
        if (ACPI_FAILURE(status)) {
                acpi_ut_remove_reference(obj_desc);
                *ddb_handle = NULL;
        }

        return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_load_table_op
 *
 * PARAMETERS:  walk_state          - Current state with operands
 *              return_desc         - Where to store the return object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Load an ACPI table from the RSDT/XSDT
 *
 ******************************************************************************/

acpi_status
acpi_ex_load_table_op(struct acpi_walk_state *walk_state,
                      union acpi_operand_object **return_desc)
{
        acpi_status status;
        union acpi_operand_object **operand = &walk_state->operands[0];
        struct acpi_namespace_node *parent_node;
        struct acpi_namespace_node *start_node;
        struct acpi_namespace_node *parameter_node = NULL;
        union acpi_operand_object *ddb_handle;
        struct acpi_table_header *table;
        u32 table_index;

        ACPI_FUNCTION_TRACE(ex_load_table_op);

        /* Validate lengths for the signature_string, OEMIDString, OEMtable_iD */

        if ((operand[0]->string.length > ACPI_NAME_SIZE) ||
            (operand[1]->string.length > ACPI_OEM_ID_SIZE) ||
            (operand[2]->string.length > ACPI_OEM_TABLE_ID_SIZE)) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        /* Find the ACPI table in the RSDT/XSDT */

        status = acpi_tb_find_table(operand[0]->string.pointer,
                                    operand[1]->string.pointer,
                                    operand[2]->string.pointer, &table_index);
        if (ACPI_FAILURE(status)) {
                if (status != AE_NOT_FOUND) {
                        return_ACPI_STATUS(status);
                }

                /* Table not found, return an Integer=0 and AE_OK */

                ddb_handle = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
                if (!ddb_handle) {
                        return_ACPI_STATUS(AE_NO_MEMORY);
                }

                ddb_handle->integer.value = 0;
                *return_desc = ddb_handle;

                return_ACPI_STATUS(AE_OK);
        }

        /* Default nodes */

        start_node = walk_state->scope_info->scope.node;
        parent_node = acpi_gbl_root_node;

        /* root_path (optional parameter) */

        if (operand[3]->string.length > 0) {
                /*
                 * Find the node referenced by the root_path_string. This is the
                 * location within the namespace where the table will be loaded.
                 */
                status =
                    acpi_ns_get_node(start_node, operand[3]->string.pointer,
                                     ACPI_NS_SEARCH_PARENT, &parent_node);
                if (ACPI_FAILURE(status)) {
                        return_ACPI_STATUS(status);
                }
        }

        /* parameter_path (optional parameter) */

        if (operand[4]->string.length > 0) {
                if ((operand[4]->string.pointer[0] != '\\') &&
                    (operand[4]->string.pointer[0] != '^')) {
                        /*
                         * Path is not absolute, so it will be relative to the node
                         * referenced by the root_path_string (or the NS root if omitted)
                         */
                        start_node = parent_node;
                }

                /* Find the node referenced by the parameter_path_string */

                status =
                    acpi_ns_get_node(start_node, operand[4]->string.pointer,
                                     ACPI_NS_SEARCH_PARENT, &parameter_node);
                if (ACPI_FAILURE(status)) {
                        return_ACPI_STATUS(status);
                }
        }

        /* Load the table into the namespace */

        status = acpi_ex_add_table(table_index, parent_node, &ddb_handle);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Parameter Data (optional) */

        if (parameter_node) {

                /* Store the parameter data into the optional parameter object */

                status = acpi_ex_store(operand[5],
                                       ACPI_CAST_PTR(union acpi_operand_object,
                                                     parameter_node),
                                       walk_state);
                if (ACPI_FAILURE(status)) {
                        (void)acpi_ex_unload_table(ddb_handle);

                        acpi_ut_remove_reference(ddb_handle);
                        return_ACPI_STATUS(status);
                }
        }

        status = acpi_get_table_by_index(table_index, &table);
        if (ACPI_SUCCESS(status)) {
                ACPI_INFO((AE_INFO,
                           "Dynamic OEM Table Load - [%.4s] OemId [%.6s] OemTableId [%.8s]",
                           table->signature, table->oem_id,
                           table->oem_table_id));
        }

        /* Invoke table handler if present */

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

        *return_desc = ddb_handle;
        return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_load_op
 *
 * PARAMETERS:  obj_desc        - Region or Buffer/Field where the table will be
 *                                obtained
 *              Target          - Where a handle to the table will be stored
 *              walk_state      - Current state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Load an ACPI table from a field or operation region
 *
 * NOTE: Region Fields (Field, bank_field, index_fields) are resolved to buffer
 *       objects before this code is reached.
 *
 *       If source is an operation region, it must refer to system_memory, as
 *       per the ACPI specification.
 *
 ******************************************************************************/

acpi_status
acpi_ex_load_op(union acpi_operand_object *obj_desc,
                union acpi_operand_object *target,
                struct acpi_walk_state *walk_state)
{
        union acpi_operand_object *ddb_handle;
        struct acpi_table_header *table;
        struct acpi_table_desc table_desc;
        u32 table_index;
        acpi_status status;
        u32 length;

        ACPI_FUNCTION_TRACE(ex_load_op);

        ACPI_MEMSET(&table_desc, 0, sizeof(struct acpi_table_desc));

        /* Source Object can be either an op_region or a Buffer/Field */

        switch (obj_desc->common.type) {
        case ACPI_TYPE_REGION:

                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                                  "Load table from Region %p\n", obj_desc));

                /* Region must be system_memory (from ACPI spec) */

                if (obj_desc->region.space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) {
                        return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
                }

                /*
                 * If the Region Address and Length have not been previously evaluated,
                 * evaluate them now and save the results.
                 */
                if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
                        status = acpi_ds_get_region_arguments(obj_desc);
                        if (ACPI_FAILURE(status)) {
                                return_ACPI_STATUS(status);
                        }
                }

                /*
                 * Map the table header and get the actual table length. The region
                 * length is not guaranteed to be the same as the table length.
                 */
                table = acpi_os_map_memory(obj_desc->region.address,
                                           sizeof(struct acpi_table_header));
                if (!table) {
                        return_ACPI_STATUS(AE_NO_MEMORY);
                }

                length = table->length;
                acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));

                /* Must have at least an ACPI table header */

                if (length < sizeof(struct acpi_table_header)) {
                        return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
                }

                /*
                 * The memory region is not guaranteed to remain stable and we must
                 * copy the table to a local buffer. For example, the memory region
                 * is corrupted after suspend on some machines. Dynamically loaded
                 * tables are usually small, so this overhead is minimal.
                 */

                /* Allocate a buffer for the table */

                table_desc.pointer = ACPI_ALLOCATE(length);
                if (!table_desc.pointer) {
                        return_ACPI_STATUS(AE_NO_MEMORY);
                }

                /* Map the entire table and copy it */

                table = acpi_os_map_memory(obj_desc->region.address, length);
                if (!table) {
                        ACPI_FREE(table_desc.pointer);
                        return_ACPI_STATUS(AE_NO_MEMORY);
                }

                ACPI_MEMCPY(table_desc.pointer, table, length);
                acpi_os_unmap_memory(table, length);

                table_desc.address = obj_desc->region.address;
                break;

        case ACPI_TYPE_BUFFER:  /* Buffer or resolved region_field */

                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                                  "Load table from Buffer or Field %p\n",
                                  obj_desc));

                /* Must have at least an ACPI table header */

                if (obj_desc->buffer.length < sizeof(struct acpi_table_header)) {
                        return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
                }

                /* Get the actual table length from the table header */

                table =
                    ACPI_CAST_PTR(struct acpi_table_header,
                                  obj_desc->buffer.pointer);
                length = table->length;

                /* Table cannot extend beyond the buffer */

                if (length > obj_desc->buffer.length) {
                        return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
                }
                if (length < sizeof(struct acpi_table_header)) {
                        return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
                }

                /*
                 * Copy the table from the buffer because the buffer could be modified
                 * or even deleted in the future
                 */
                table_desc.pointer = ACPI_ALLOCATE(length);
                if (!table_desc.pointer) {
                        return_ACPI_STATUS(AE_NO_MEMORY);
                }

                ACPI_MEMCPY(table_desc.pointer, table, length);
                table_desc.address = ACPI_TO_INTEGER(table_desc.pointer);
                break;

        default:
                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
        }

        /* Validate table checksum (will not get validated in tb_add_table) */

        status = acpi_tb_verify_checksum(table_desc.pointer, length);
        if (ACPI_FAILURE(status)) {
                ACPI_FREE(table_desc.pointer);
                return_ACPI_STATUS(status);
        }

        /* Complete the table descriptor */

        table_desc.length = length;
        table_desc.flags = ACPI_TABLE_ORIGIN_ALLOCATED;

        /* Install the new table into the local data structures */

        status = acpi_tb_add_table(&table_desc, &table_index);
        if (ACPI_FAILURE(status)) {
                goto cleanup;
        }

        /*
         * Add the table to the namespace.
         *
         * Note: Load the table objects relative to the root of the namespace.
         * This appears to go against the ACPI specification, but we do it for
         * compatibility with other ACPI implementations.
         */
        status =
            acpi_ex_add_table(table_index, acpi_gbl_root_node, &ddb_handle);
        if (ACPI_FAILURE(status)) {

                /* On error, table_ptr was deallocated above */

                return_ACPI_STATUS(status);
        }

        /* Store the ddb_handle into the Target operand */

        status = acpi_ex_store(ddb_handle, target, walk_state);
        if (ACPI_FAILURE(status)) {
                (void)acpi_ex_unload_table(ddb_handle);

                /* table_ptr was deallocated above */

                acpi_ut_remove_reference(ddb_handle);
                return_ACPI_STATUS(status);
        }

        /* Remove the reference by added by acpi_ex_store above */

        acpi_ut_remove_reference(ddb_handle);

        /* Invoke table handler if present */

        if (acpi_gbl_table_handler) {
                (void)acpi_gbl_table_handler(ACPI_TABLE_EVENT_LOAD,
                                             table_desc.pointer,
                                             acpi_gbl_table_handler_context);
        }

      cleanup:
        if (ACPI_FAILURE(status)) {

                /* Delete allocated table buffer */

                acpi_tb_delete_table(&table_desc);
        }
        return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_unload_table
 *
 * PARAMETERS:  ddb_handle          - Handle to a previously loaded table
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Unload an ACPI table
 *
 ******************************************************************************/

acpi_status acpi_ex_unload_table(union acpi_operand_object *ddb_handle)
{
        acpi_status status = AE_OK;
        union acpi_operand_object *table_desc = ddb_handle;
        u32 table_index;
        struct acpi_table_header *table;

        ACPI_FUNCTION_TRACE(ex_unload_table);

        /*
         * Validate the handle
         * Although the handle is partially validated in acpi_ex_reconfiguration()
         * when it calls acpi_ex_resolve_operands(), the handle is more completely
         * validated here.
         *
         * Handle must be a valid operand object of type reference. Also, the
         * ddb_handle must still be marked valid (table has not been previously
         * unloaded)
         */
        if ((!ddb_handle) ||
            (ACPI_GET_DESCRIPTOR_TYPE(ddb_handle) != ACPI_DESC_TYPE_OPERAND) ||
            (ddb_handle->common.type != ACPI_TYPE_LOCAL_REFERENCE) ||
            (!(ddb_handle->common.flags & AOPOBJ_DATA_VALID))) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        /* Get the table index from the ddb_handle */

        table_index = table_desc->reference.value;

        /* Ensure the table is still loaded */

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

        /* Invoke table handler if present */

        if (acpi_gbl_table_handler) {
                status = acpi_get_table_by_index(table_index, &table);
                if (ACPI_SUCCESS(status)) {
                        (void)acpi_gbl_table_handler(ACPI_TABLE_EVENT_UNLOAD,
                                                     table,
                                                     acpi_gbl_table_handler_context);
                }
        }

        /* 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);

        /*
         * Invalidate the handle. We do this because the handle may be stored
         * in a named object and may not be actually deleted until much later.
         */
        ddb_handle->common.flags &= ~AOPOBJ_DATA_VALID;
        return_ACPI_STATUS(AE_OK);
}