[PATCH] fix semaphore handling in __unregister_chrdev_region

[linux/fpc-iii.git] / drivers / acpi / tables / tbinstal.c

/******************************************************************************
 *
 * Module Name: tbinstal - ACPI table installation and removal
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2005, R. Byron Moore
 * 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 <acpi/actables.h>


#define _COMPONENT          ACPI_TABLES
         ACPI_MODULE_NAME    ("tbinstal")


/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_match_signature
 *
 * PARAMETERS:  Signature           - Table signature to match
 *              table_info          - Return data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Compare signature against the list of "ACPI-subsystem-owned"
 *              tables (DSDT/FADT/SSDT, etc.) Returns the table_type_iD on match.
 *
 ******************************************************************************/

acpi_status
acpi_tb_match_signature (
        char                            *signature,
        struct acpi_table_desc          *table_info,
        u8                              search_type)
{
        acpi_native_uint                i;


        ACPI_FUNCTION_TRACE ("tb_match_signature");


        /*
         * Search for a signature match among the known table types
         */
        for (i = 0; i < NUM_ACPI_TABLE_TYPES; i++) {
                if (!(acpi_gbl_table_data[i].flags & search_type)) {
                        continue;
                }

                if (!ACPI_STRNCMP (signature, acpi_gbl_table_data[i].signature,
                                   acpi_gbl_table_data[i].sig_length)) {
                        /* Found a signature match, return index if requested */

                        if (table_info) {
                                table_info->type = (u8) i;
                        }

                        ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                                "Table [%4.4s] is an ACPI table consumed by the core subsystem\n",
                                (char *) acpi_gbl_table_data[i].signature));

                        return_ACPI_STATUS (AE_OK);
                }
        }

        ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                "Table [%4.4s] is not an ACPI table consumed by the core subsystem - ignored\n",
                (char *) signature));

        return_ACPI_STATUS (AE_TABLE_NOT_SUPPORTED);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_install_table
 *
 * PARAMETERS:  table_info          - Return value from acpi_tb_get_table_body
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Load and validate all tables other than the RSDT.  The RSDT must
 *              already be loaded and validated.
 *              Install the table into the global data structs.
 *
 ******************************************************************************/

acpi_status
acpi_tb_install_table (
        struct acpi_table_desc          *table_info)
{
        acpi_status                     status;

        ACPI_FUNCTION_TRACE ("tb_install_table");


        /* Lock tables while installing */

        status = acpi_ut_acquire_mutex (ACPI_MTX_TABLES);
        if (ACPI_FAILURE (status)) {
                ACPI_REPORT_ERROR (("Could not acquire table mutex for [%4.4s], %s\n",
                        table_info->pointer->signature, acpi_format_exception (status)));
                return_ACPI_STATUS (status);
        }

        /* Install the table into the global data structure */

        status = acpi_tb_init_table_descriptor (table_info->type, table_info);
        if (ACPI_FAILURE (status)) {
                ACPI_REPORT_ERROR (("Could not install ACPI table [%4.4s], %s\n",
                        table_info->pointer->signature, acpi_format_exception (status)));
        }

        ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "%s located at %p\n",
                acpi_gbl_table_data[table_info->type].name, table_info->pointer));

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


/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_recognize_table
 *
 * PARAMETERS:  table_info          - Return value from acpi_tb_get_table_body
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Check a table signature for a match against known table types
 *
 * NOTE:  All table pointers are validated as follows:
 *          1) Table pointer must point to valid physical memory
 *          2) Signature must be 4 ASCII chars, even if we don't recognize the
 *             name
 *          3) Table must be readable for length specified in the header
 *          4) Table checksum must be valid (with the exception of the FACS
 *             which has no checksum for some odd reason)
 *
 ******************************************************************************/

acpi_status
acpi_tb_recognize_table (
        struct acpi_table_desc          *table_info,
        u8                              search_type)
{
        struct acpi_table_header        *table_header;
        acpi_status                     status;


        ACPI_FUNCTION_TRACE ("tb_recognize_table");


        /* Ensure that we have a valid table pointer */

        table_header = (struct acpi_table_header *) table_info->pointer;
        if (!table_header) {
                return_ACPI_STATUS (AE_BAD_PARAMETER);
        }

        /*
         * We only "recognize" a limited number of ACPI tables -- namely, the
         * ones that are used by the subsystem (DSDT, FADT, etc.)
         *
         * An AE_TABLE_NOT_SUPPORTED means that the table was not recognized.
         * This can be any one of many valid ACPI tables, it just isn't one of
         * the tables that is consumed by the core subsystem
         */
        status = acpi_tb_match_signature (table_header->signature, table_info, search_type);
        if (ACPI_FAILURE (status)) {
                return_ACPI_STATUS (status);
        }

        status = acpi_tb_validate_table_header (table_header);
        if (ACPI_FAILURE (status)) {
                return_ACPI_STATUS (status);
        }

        /* Return the table type and length via the info struct */

        table_info->length = (acpi_size) table_header->length;

        return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_init_table_descriptor
 *
 * PARAMETERS:  table_type          - The type of the table
 *              table_info          - A table info struct
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Install a table into the global data structs.
 *
 ******************************************************************************/

acpi_status
acpi_tb_init_table_descriptor (
        acpi_table_type                 table_type,
        struct acpi_table_desc          *table_info)
{
        struct acpi_table_list          *list_head;
        struct acpi_table_desc          *table_desc;


        ACPI_FUNCTION_TRACE_U32 ("tb_init_table_descriptor", table_type);


        /* Allocate a descriptor for this table */

        table_desc = ACPI_MEM_CALLOCATE (sizeof (struct acpi_table_desc));
        if (!table_desc) {
                return_ACPI_STATUS (AE_NO_MEMORY);
        }

        /*
         * Install the table into the global data structure
         */
        list_head = &acpi_gbl_table_lists[table_type];

        /*
         * Two major types of tables:  1) Only one instance is allowed.  This
         * includes most ACPI tables such as the DSDT.  2) Multiple instances of
         * the table are allowed.  This includes SSDT and PSDTs.
         */
        if (ACPI_IS_SINGLE_TABLE (acpi_gbl_table_data[table_type].flags)) {
                /*
                 * Only one table allowed, and a table has alread been installed
                 * at this location, so return an error.
                 */
                if (list_head->next) {
                        ACPI_MEM_FREE (table_desc);
                        return_ACPI_STATUS (AE_ALREADY_EXISTS);
                }

                table_desc->next = list_head->next;
                list_head->next = table_desc;

                if (table_desc->next) {
                        table_desc->next->prev = table_desc;
                }

                list_head->count++;
        }
        else {
                /*
                 * Link the new table in to the list of tables of this type.
                 * Insert at the end of the list, order IS IMPORTANT.
                 *
                 * table_desc->Prev & Next are already NULL from calloc()
                 */
                list_head->count++;

                if (!list_head->next) {
                        list_head->next = table_desc;
                }
                else {
                        table_desc->next = list_head->next;

                        while (table_desc->next->next) {
                                table_desc->next = table_desc->next->next;
                        }

                        table_desc->next->next = table_desc;
                        table_desc->prev = table_desc->next;
                        table_desc->next = NULL;
                }
        }

        /* Finish initialization of the table descriptor */

        table_desc->type                = (u8) table_type;
        table_desc->pointer             = table_info->pointer;
        table_desc->length              = table_info->length;
        table_desc->allocation          = table_info->allocation;
        table_desc->aml_start           = (u8 *) (table_desc->pointer + 1),
        table_desc->aml_length          = (u32) (table_desc->length -
                         (u32) sizeof (struct acpi_table_header));
        table_desc->table_id            = acpi_ut_allocate_owner_id (ACPI_OWNER_TYPE_TABLE);
        table_desc->loaded_into_namespace = FALSE;

        /*
         * Set the appropriate global pointer (if there is one) to point to the
         * newly installed table
         */
        if (acpi_gbl_table_data[table_type].global_ptr) {
                *(acpi_gbl_table_data[table_type].global_ptr) = table_info->pointer;
        }

        /* Return Data */

        table_info->table_id        = table_desc->table_id;
        table_info->installed_desc  = table_desc;

        return_ACPI_STATUS (AE_OK);
}


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

void
acpi_tb_delete_all_tables (void)
{
        acpi_table_type                 type;


        /*
         * Free memory allocated for ACPI tables
         * Memory can either be mapped or allocated
         */
        for (type = 0; type < NUM_ACPI_TABLE_TYPES; type++) {
                acpi_tb_delete_tables_by_type (type);
        }
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_delete_tables_by_type
 *
 * PARAMETERS:  Type                - The table type to be deleted
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Delete an internal ACPI table
 *              Locks the ACPI table mutex
 *
 ******************************************************************************/

void
acpi_tb_delete_tables_by_type (
        acpi_table_type                 type)
{
        struct acpi_table_desc          *table_desc;
        u32                             count;
        u32                             i;


        ACPI_FUNCTION_TRACE_U32 ("tb_delete_tables_by_type", type);


        if (type > ACPI_TABLE_MAX) {
                return_VOID;
        }

        if (ACPI_FAILURE (acpi_ut_acquire_mutex (ACPI_MTX_TABLES))) {
                return;
        }

        /* Clear the appropriate "typed" global table pointer */

        switch (type) {
        case ACPI_TABLE_RSDP:
                acpi_gbl_RSDP = NULL;
                break;

        case ACPI_TABLE_DSDT:
                acpi_gbl_DSDT = NULL;
                break;

        case ACPI_TABLE_FADT:
                acpi_gbl_FADT = NULL;
                break;

        case ACPI_TABLE_FACS:
                acpi_gbl_FACS = NULL;
                break;

        case ACPI_TABLE_XSDT:
                acpi_gbl_XSDT = NULL;
                break;

        case ACPI_TABLE_SSDT:
        case ACPI_TABLE_PSDT:
        default:
                break;
        }

        /*
         * Free the table
         * 1) Get the head of the list
         */
        table_desc = acpi_gbl_table_lists[type].next;
        count     = acpi_gbl_table_lists[type].count;

        /*
         * 2) Walk the entire list, deleting both the allocated tables
         *    and the table descriptors
         */
        for (i = 0; i < count; i++) {
                table_desc = acpi_tb_uninstall_table (table_desc);
        }

        (void) acpi_ut_release_mutex (ACPI_MTX_TABLES);
        return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_delete_single_table
 *
 * PARAMETERS:  table_info          - A table info struct
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Low-level free for a single ACPI table.  Handles cases where
 *              the table was allocated a buffer or was mapped.
 *
 ******************************************************************************/

void
acpi_tb_delete_single_table (
        struct acpi_table_desc          *table_desc)
{

        /* Must have a valid table descriptor and pointer */

        if ((!table_desc) ||
                 (!table_desc->pointer)) {
                return;
        }

        /* Valid table, determine type of memory allocation */

        switch (table_desc->allocation) {
        case ACPI_MEM_NOT_ALLOCATED:
                break;

        case ACPI_MEM_ALLOCATED:

                ACPI_MEM_FREE (table_desc->pointer);
                break;

        case ACPI_MEM_MAPPED:

                acpi_os_unmap_memory (table_desc->pointer, table_desc->length);
                break;

        default:
                break;
        }
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_uninstall_table
 *
 * PARAMETERS:  table_info          - A table info struct
 *
 * RETURN:      Pointer to the next table in the list (of same type)
 *
 * DESCRIPTION: Free the memory associated with an internal ACPI table that
 *              is either installed or has never been installed.
 *              Table mutex should be locked.
 *
 ******************************************************************************/

struct acpi_table_desc *
acpi_tb_uninstall_table (
        struct acpi_table_desc          *table_desc)
{
        struct acpi_table_desc          *next_desc;


        ACPI_FUNCTION_TRACE_PTR ("tb_uninstall_table", table_desc);


        if (!table_desc) {
                return_PTR (NULL);
        }

        /* Unlink the descriptor from the doubly linked list */

        if (table_desc->prev) {
                table_desc->prev->next = table_desc->next;
        }
        else {
                /* Is first on list, update list head */

                acpi_gbl_table_lists[table_desc->type].next = table_desc->next;
        }

        if (table_desc->next) {
                table_desc->next->prev = table_desc->prev;
        }

        /* Free the memory allocated for the table itself */

        acpi_tb_delete_single_table (table_desc);

        /* Free the table descriptor */

        next_desc = table_desc->next;
        ACPI_MEM_FREE (table_desc);

        /* Return pointer to the next descriptor */

        return_PTR (next_desc);
}