1
linux/drivers/acpi/acpica/tbinstal.c
Bob Moore 8a335a2331 ACPICA: Fix AcpiWalkNamespace race condition with table unload
Added a reader/writer locking mechanism to allow multiple
concurrent namespace walks (readers), but a dynamic table unload
will have exclusive access to the namespace. This fixes a problem
where a table unload could delete the portion of the namespace that
is currently being examined by a walk.  Adds a new file, utlock.c
that implements the reader/writer lock mechanism. ACPICA BZ 749.

http://www.acpica.org/bugzilla/show_bug.cgi?id=749

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-03-27 12:11:02 -04:00

631 lines
18 KiB
C

/******************************************************************************
*
* Module Name: tbinstal - ACPI table installation and removal
*
*****************************************************************************/
/*
* 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 "acnamesp.h"
#include "actables.h"
#define _COMPONENT ACPI_TABLES
ACPI_MODULE_NAME("tbinstal")
/******************************************************************************
*
* FUNCTION: acpi_tb_verify_table
*
* PARAMETERS: table_desc - table
*
* RETURN: Status
*
* DESCRIPTION: this function is called to verify and map table
*
*****************************************************************************/
acpi_status acpi_tb_verify_table(struct acpi_table_desc *table_desc)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(tb_verify_table);
/* Map the table if necessary */
if (!table_desc->pointer) {
if ((table_desc->flags & ACPI_TABLE_ORIGIN_MASK) ==
ACPI_TABLE_ORIGIN_MAPPED) {
table_desc->pointer =
acpi_os_map_memory(table_desc->address,
table_desc->length);
}
if (!table_desc->pointer) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
}
/* FACS is the odd table, has no standard ACPI header and no checksum */
if (!ACPI_COMPARE_NAME(&table_desc->signature, ACPI_SIG_FACS)) {
/* Always calculate checksum, ignore bad checksum if requested */
status =
acpi_tb_verify_checksum(table_desc->pointer,
table_desc->length);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_tb_add_table
*
* PARAMETERS: table_desc - Table descriptor
* table_index - Where the table index is returned
*
* RETURN: Status
*
* DESCRIPTION: This function is called to add an ACPI table. It is used to
* dynamically load tables via the Load and load_table AML
* operators.
*
******************************************************************************/
acpi_status
acpi_tb_add_table(struct acpi_table_desc *table_desc, u32 *table_index)
{
u32 i;
acpi_status status = AE_OK;
struct acpi_table_header *override_table = NULL;
ACPI_FUNCTION_TRACE(tb_add_table);
if (!table_desc->pointer) {
status = acpi_tb_verify_table(table_desc);
if (ACPI_FAILURE(status) || !table_desc->pointer) {
return_ACPI_STATUS(status);
}
}
/*
* Originally, we checked the table signature for "SSDT" or "PSDT" here.
* Next, we added support for OEMx tables, signature "OEM".
* Valid tables were encountered with a null signature, so we've just
* given up on validating the signature, since it seems to be a waste
* of code. The original code was removed (05/2008).
*/
(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
/* Check if table is already registered */
for (i = 0; i < acpi_gbl_root_table_list.count; ++i) {
if (!acpi_gbl_root_table_list.tables[i].pointer) {
status =
acpi_tb_verify_table(&acpi_gbl_root_table_list.
tables[i]);
if (ACPI_FAILURE(status)
|| !acpi_gbl_root_table_list.tables[i].pointer) {
continue;
}
}
/*
* Check for a table match on the entire table length,
* not just the header.
*/
if (table_desc->length !=
acpi_gbl_root_table_list.tables[i].length) {
continue;
}
if (ACPI_MEMCMP(table_desc->pointer,
acpi_gbl_root_table_list.tables[i].pointer,
acpi_gbl_root_table_list.tables[i].length)) {
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.
*/
/*
* Table is already registered.
* We can delete the table that was passed as a parameter.
*/
acpi_tb_delete_table(table_desc);
*table_index = i;
if (acpi_gbl_root_table_list.tables[i].
flags & ACPI_TABLE_IS_LOADED) {
/* Table is still loaded, this is an error */
status = AE_ALREADY_EXISTS;
goto release;
} else {
/* Table was unloaded, allow it to be reloaded */
table_desc->pointer =
acpi_gbl_root_table_list.tables[i].pointer;
table_desc->address =
acpi_gbl_root_table_list.tables[i].address;
status = AE_OK;
goto print_header;
}
}
/*
* ACPI Table Override:
* Allow the host to override dynamically loaded tables.
*/
status = acpi_os_table_override(table_desc->pointer, &override_table);
if (ACPI_SUCCESS(status) && override_table) {
ACPI_INFO((AE_INFO,
"%4.4s @ 0x%p Table override, replaced with:",
table_desc->pointer->signature,
ACPI_CAST_PTR(void, table_desc->address)));
/* We can delete the table that was passed as a parameter */
acpi_tb_delete_table(table_desc);
/* Setup descriptor for the new table */
table_desc->address = ACPI_PTR_TO_PHYSADDR(override_table);
table_desc->pointer = override_table;
table_desc->length = override_table->length;
table_desc->flags = ACPI_TABLE_ORIGIN_OVERRIDE;
}
/* Add the table to the global root table list */
status = acpi_tb_store_table(table_desc->address, table_desc->pointer,
table_desc->length, table_desc->flags,
table_index);
if (ACPI_FAILURE(status)) {
goto release;
}
print_header:
acpi_tb_print_table_header(table_desc->address, table_desc->pointer);
release:
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
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;
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 */
tables = ACPI_ALLOCATE_ZEROED(((acpi_size) acpi_gbl_root_table_list.
size +
ACPI_ROOT_TABLE_SIZE_INCREMENT) *
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 */
if (acpi_gbl_root_table_list.tables) {
ACPI_MEMCPY(tables, acpi_gbl_root_table_list.tables,
(acpi_size) acpi_gbl_root_table_list.size *
sizeof(struct acpi_table_desc));
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.size += ACPI_ROOT_TABLE_SIZE_INCREMENT;
acpi_gbl_root_table_list.flags |= (u8) ACPI_ROOT_ORIGIN_ALLOCATED;
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_tb_store_table
*
* PARAMETERS: Address - Table address
* Table - Table header
* Length - Table length
* Flags - flags
*
* RETURN: Status and table index.
*
* DESCRIPTION: Add an ACPI table to the global table list
*
******************************************************************************/
acpi_status
acpi_tb_store_table(acpi_physical_address address,
struct acpi_table_header *table,
u32 length, u8 flags, u32 *table_index)
{
acpi_status status = AE_OK;
/* Ensure that there is room for the table in the Root Table List */
if (acpi_gbl_root_table_list.count >= acpi_gbl_root_table_list.size) {
status = acpi_tb_resize_root_table_list();
if (ACPI_FAILURE(status)) {
return (status);
}
}
/* Initialize added table */
acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
address = address;
acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
pointer = table;
acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].length =
length;
acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
owner_id = 0;
acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].flags =
flags;
ACPI_MOVE_32_TO_32(&
(acpi_gbl_root_table_list.
tables[acpi_gbl_root_table_list.count].signature),
table->signature);
*table_index = acpi_gbl_root_table_list.count;
acpi_gbl_root_table_list.count++;
return (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_tb_delete_table
*
* PARAMETERS: table_index - Table index
*
* RETURN: None
*
* DESCRIPTION: Delete one internal ACPI table
*
******************************************************************************/
void acpi_tb_delete_table(struct acpi_table_desc *table_desc)
{
/* Table must be mapped or allocated */
if (!table_desc->pointer) {
return;
}
switch (table_desc->flags & ACPI_TABLE_ORIGIN_MASK) {
case ACPI_TABLE_ORIGIN_MAPPED:
acpi_os_unmap_memory(table_desc->pointer, table_desc->length);
break;
case ACPI_TABLE_ORIGIN_ALLOCATED:
ACPI_FREE(table_desc->pointer);
break;
default:;
}
table_desc->pointer = NULL;
}
/*******************************************************************************
*
* 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.count; ++i) {
acpi_tb_delete_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.count = 0;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "ACPI Tables freed\n"));
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
}
/*******************************************************************************
*
* 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.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.
*/
acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
status = acpi_ut_acquire_write_lock(&acpi_gbl_namespace_rw_lock);
acpi_ns_delete_namespace_by_owner(owner_id);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
acpi_ut_release_write_lock(&acpi_gbl_namespace_rw_lock);
status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
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.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.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.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 - Table index
*
* 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.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.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);
}