exconfig.c

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

/*
 * Copyright (C) 2000 - 2012, 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"
#include "acevents.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);

static acpi_status
acpi_ex_region_read(union acpi_operand_object *obj_desc,
            u32 length, u8 *buffer);

/*******************************************************************************
 *
 * 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)
{
    union acpi_operand_object *obj_desc;
    acpi_status status;
    acpi_owner_id owner_id;

    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);
    }

    /* Execute any module-level code that was found in the table */

    acpi_ex_exit_interpreter();
    acpi_ns_exec_module_code_list();
    acpi_ex_enter_interpreter();

    /* Update GPEs for any new _Lxx/_Exx methods. Ignore errors */

    status = acpi_tb_get_owner_id(table_index, &owner_id);
    if (ACPI_SUCCESS(status)) {
        acpi_ev_update_gpes(owner_id);
    }

    return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * 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_integer_object((u64) 0);
        if (!ddb_handle) {
            return_ACPI_STATUS(AE_NO_MEMORY);
        }

        *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:"));
        acpi_tb_print_table_header(0, table);
    }

    /* 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_region_read
 *
 * PARAMETERS:  obj_desc        - Region descriptor
 *              length          - Number of bytes to read
 *              buffer          - Pointer to where to put the data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Read data from an operation region. The read starts from the
 *              beginning of the region.
 *
 ******************************************************************************/

static acpi_status
acpi_ex_region_read(union acpi_operand_object *obj_desc, u32 length, u8 *buffer)
{
    acpi_status status;
    u64 value;
    u32 region_offset = 0;
    u32 i;

    /* Bytewise reads */

    for (i = 0; i < length; i++) {
        status =
            acpi_ev_address_space_dispatch(obj_desc, NULL, ACPI_READ,
                           region_offset, 8, &value);
        if (ACPI_FAILURE(status)) {
            return status;
        }

        *buffer = (u8)value;
        buffer++;
        region_offset++;
    }

    return AE_OK;
}

/*******************************************************************************
 *
 * 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);
            }
        }

        /* Get the table header first so we can get the table length */

        table = ACPI_ALLOCATE(sizeof(struct acpi_table_header));
        if (!table) {
            return_ACPI_STATUS(AE_NO_MEMORY);
        }

        status =
            acpi_ex_region_read(obj_desc,
                    sizeof(struct acpi_table_header),
                    ACPI_CAST_PTR(u8, table));
        length = table->length;
        ACPI_FREE(table);

        if (ACPI_FAILURE(status)) {
            return_ACPI_STATUS(status);
        }

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

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

        /*
         * The original implementation simply mapped the table, with no copy.
         * However, 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.
         *
         * The latest implementation (5/2009) does not use a mapping at all.
         * We use the low-level operation region interface to read the table
         * instead of the obvious optimization of using a direct mapping.
         * This maintains a consistent use of operation regions across the
         * entire subsystem. This is important if additional processing must
         * be performed in the (possibly user-installed) operation region
         * handler. For example, acpi_exec and ASLTS depend on this.
         */

        /* Allocate a buffer for the table */

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

        /* Read the entire table */

        status = acpi_ex_region_read(obj_desc, length,
                         ACPI_CAST_PTR(u8,
                               table_desc.pointer));
        if (ACPI_FAILURE(status)) {
            ACPI_FREE(table_desc.pointer);
            return_ACPI_STATUS(status);
        }

        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)) {

        /* Delete allocated table buffer */

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

    /*
     * 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);
    }

    ACPI_INFO((AE_INFO, "Dynamic OEM Table Load:"));
    acpi_tb_print_table_header(0, table_desc.pointer);

    /* 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);
    }

    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);
}