/*******************************************************************************
*
* Module Name: utownerid - Support for Table/Method Owner IDs
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2013, 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"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utownerid")
/*******************************************************************************
*
* FUNCTION: acpi_ut_allocate_owner_id
*
* PARAMETERS: owner_id - Where the new owner ID is returned
*
* RETURN: Status
*
* DESCRIPTION: Allocate a table or method owner ID. The owner ID is used to
* track objects created by the table or method, to be deleted
* when the method exits or the table is unloaded.
*
******************************************************************************/
acpi_status acpi_ut_allocate_owner_id(acpi_owner_id * owner_id)
{
u32 i;
u32 j;
u32 k;
acpi_status status;
ACPI_FUNCTION_TRACE(ut_allocate_owner_id);
/* Guard against multiple allocations of ID to the same location */
if (*owner_id) {
ACPI_ERROR((AE_INFO, "Owner ID [0x%2.2X] already exists",
*owner_id));
return_ACPI_STATUS(AE_ALREADY_EXISTS);
}
/* Mutex for the global ID mask */
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Find a free owner ID, cycle through all possible IDs on repeated
* allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index may have
* to be scanned twice.
*/
for (i = 0, j = acpi_gbl_last_owner_id_index;
i < (ACPI_NUM_OWNERID_MASKS + 1); i++, j++) {
if (j >= ACPI_NUM_OWNERID_MASKS) {
j = 0; /* Wraparound to start of mask array */
}
for (k = acpi_gbl_next_owner_id_offset; k < 32; k++) {
if (acpi_gbl_owner_id_mask[j] == ACPI_UINT32_MAX) {
/* There are no free IDs in this mask */
break;
}
if (!(acpi_gbl_owner_id_mask[j] & (1 << k))) {
/*
* Found a free ID. The actual ID is the bit index plus one,
* making zero an invalid Owner ID. Save this as the last ID
* allocated and update the global ID mask.
*/
acpi_gbl_owner_id_mask[j] |= (1 << k);
acpi_gbl_last_owner_id_index = (u8)j;
acpi_gbl_next_owner_id_offset = (u8)(k + 1);
/*
* Construct encoded ID from the index and bit position
*
* Note: Last [j].k (bit 255) is never used and is marked
* permanently allocated (prevents +1 overflow)
*/
*owner_id =
(acpi_owner_id) ((k + 1) + ACPI_MUL_32(j));
ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
"Allocated OwnerId: %2.2X\n",
(unsigned int)*owner_id));
goto exit;
}
}
acpi_gbl_next_owner_id_offset = 0;
}
/*
* All owner_ids have been allocated. This typically should
* not happen since the IDs are reused after deallocation. The IDs are
* allocated upon table load (one per table) and method execution, and
* they are released when a table is unloaded or a method completes
* execution.
*
* If this error happens, there may be very deep nesting of invoked control
* methods, or there may be a bug where the IDs are not released.
*/
status = AE_OWNER_ID_LIMIT;
ACPI_ERROR((AE_INFO,
"Could not allocate new OwnerId (255 max), AE_OWNER_ID_LIMIT"));
exit:
(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_release_owner_id
*
* PARAMETERS: owner_id_ptr - Pointer to a previously allocated owner_ID
*
* RETURN: None. No error is returned because we are either exiting a
* control method or unloading a table. Either way, we would
* ignore any error anyway.
*
* DESCRIPTION: Release a table or method owner ID. Valid IDs are 1 - 255
*
******************************************************************************/
void acpi_ut_release_owner_id(acpi_owner_id * owner_id_ptr)
{
acpi_owner_id owner_id = *owner_id_ptr;
acpi_status status;
u32 index;
u32 bit;
ACPI_FUNCTION_TRACE_U32(ut_release_owner_id, owner_id);
/* Always clear the input owner_id (zero is an invalid ID) */
*owner_id_ptr = 0;
/* Zero is not a valid owner_ID */
if (owner_id == 0) {
ACPI_ERROR((AE_INFO, "Invalid OwnerId: 0x%2.2X", owner_id));
return_VOID;
}
/* Mutex for the global ID mask */
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_VOID;
}
/* Normalize the ID to zero */
owner_id--;
/* Decode ID to index/offset pair */
index = ACPI_DIV_32(owner_id);
bit = 1 << ACPI_MOD_32(owner_id);
/* Free the owner ID only if it is valid */
if (acpi_gbl_owner_id_mask[index] & bit) {
acpi_gbl_owner_id_mask[index] ^= bit;
} else {
ACPI_ERROR((AE_INFO,
"Release of non-allocated OwnerId: 0x%2.2X",
owner_id + 1));
}
(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
return_VOID;
}