utalloc.c

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/******************************************************************************
 *
 * Module Name: utalloc - local cache and memory allocation routines
 *              $Revision: 121 $
 *
 *****************************************************************************/

/*
 *  Copyright (C) 2000 - 2002, R. Byron Moore
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "acpi.h"
#include "acparser.h"
#include "acinterp.h"
#include "acnamesp.h"
#include "acglobal.h"

#define _COMPONENT          ACPI_UTILITIES
	 ACPI_MODULE_NAME    ("utalloc")


/******************************************************************************
 *
 * FUNCTION:    Acpi_ut_release_to_cache
 *
 * PARAMETERS:  List_id             - Memory list/cache ID
 *              Object              - The object to be released
 *
 * RETURN:      None
 *
 * DESCRIPTION: Release an object to the specified cache.  If cache is full,
 *              the object is deleted.
 *
 ******************************************************************************/

void
acpi_ut_release_to_cache (
	u32                     list_id,
	void                    *object)
{
	ACPI_MEMORY_LIST        *cache_info;


	ACPI_FUNCTION_ENTRY ();


	/* If walk cache is full, just free this wallkstate object */

	cache_info = &acpi_gbl_memory_lists[list_id];
	if (cache_info->cache_depth >= cache_info->max_cache_depth) {
		ACPI_MEM_FREE (object);
		ACPI_MEM_TRACKING (cache_info->total_freed++);
	}

	/* Otherwise put this object back into the cache */

	else {
		if (ACPI_FAILURE (acpi_ut_acquire_mutex (ACPI_MTX_CACHES))) {
			return;
		}

		/* Mark the object as cached */

		ACPI_MEMSET (object, 0xCA, cache_info->object_size);
		ACPI_SET_DESCRIPTOR_TYPE (object, ACPI_CACHED_OBJECT);

		/* Put the object at the head of the cache list */

		* (char **) (((char *) object) + cache_info->link_offset) = cache_info->list_head;
		cache_info->list_head = object;
		cache_info->cache_depth++;

		(void) acpi_ut_release_mutex (ACPI_MTX_CACHES);
	}
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_ut_acquire_from_cache
 *
 * PARAMETERS:  List_id             - Memory list ID
 *
 * RETURN:      A requested object.  NULL if the object could not be
 *              allocated.
 *
 * DESCRIPTION: Get an object from the specified cache.  If cache is empty,
 *              the object is allocated.
 *
 ******************************************************************************/

void *
acpi_ut_acquire_from_cache (
	u32                     list_id)
{
	ACPI_MEMORY_LIST        *cache_info;
	void                    *object;


	ACPI_FUNCTION_NAME ("Ut_acquire_from_cache");


	cache_info = &acpi_gbl_memory_lists[list_id];
	if (ACPI_FAILURE (acpi_ut_acquire_mutex (ACPI_MTX_CACHES))) {
		return (NULL);
	}

	ACPI_MEM_TRACKING (cache_info->cache_requests++);

	/* Check the cache first */

	if (cache_info->list_head) {
		/* There is an object available, use it */

		object = cache_info->list_head;
		cache_info->list_head = * (char **) (((char *) object) + cache_info->link_offset);

		ACPI_MEM_TRACKING (cache_info->cache_hits++);
		cache_info->cache_depth--;

#ifdef ACPI_DBG_TRACK_ALLOCATIONS
		ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Object %p from %s\n",
			object, acpi_gbl_memory_lists[list_id].list_name));
#endif

		if (ACPI_FAILURE (acpi_ut_release_mutex (ACPI_MTX_CACHES))) {
			return (NULL);
		}

		/* Clear (zero) the previously used Object */

		ACPI_MEMSET (object, 0, cache_info->object_size);
	}

	else {
		/* The cache is empty, create a new object */

		/* Avoid deadlock with ACPI_MEM_CALLOCATE */

		if (ACPI_FAILURE (acpi_ut_release_mutex (ACPI_MTX_CACHES))) {
			return (NULL);
		}

		object = ACPI_MEM_CALLOCATE (cache_info->object_size);
		ACPI_MEM_TRACKING (cache_info->total_allocated++);
	}

	return (object);
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_ut_delete_generic_cache
 *
 * PARAMETERS:  List_id         - Memory list ID
 *
 * RETURN:      None
 *
 * DESCRIPTION: Free all objects within the requested cache.
 *
 ******************************************************************************/

void
acpi_ut_delete_generic_cache (
	u32                     list_id)
{
	ACPI_MEMORY_LIST        *cache_info;
	char                    *next;


	ACPI_FUNCTION_ENTRY ();


	cache_info = &acpi_gbl_memory_lists[list_id];
	while (cache_info->list_head) {
		/* Delete one cached state object */

		next = * (char **) (((char *) cache_info->list_head) + cache_info->link_offset);
		ACPI_MEM_FREE (cache_info->list_head);

		cache_info->list_head = next;
		cache_info->cache_depth--;
	}
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_validate_buffer
 *
 * PARAMETERS:  Buffer              - Buffer descriptor to be validated
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform parameter validation checks on an acpi_buffer
 *
 ******************************************************************************/

acpi_status
acpi_ut_validate_buffer (
	acpi_buffer             *buffer)
{

	/* Obviously, the structure pointer must be valid */

	if (!buffer) {
		return (AE_BAD_PARAMETER);
	}

	/* Special semantics for the length */

	if ((buffer->length == ACPI_NO_BUFFER)              ||
		(buffer->length == ACPI_ALLOCATE_BUFFER)        ||
		(buffer->length == ACPI_ALLOCATE_LOCAL_BUFFER)) {
		return (AE_OK);
	}

	/* Length is valid, the buffer pointer must be also */

	if (!buffer->pointer) {
		return (AE_BAD_PARAMETER);
	}

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_initialize_buffer
 *
 * PARAMETERS:  Required_length     - Length needed
 *              Buffer              - Buffer to be validated
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Validate that the buffer is of the required length or
 *              allocate a new buffer.
 *
 ******************************************************************************/

acpi_status
acpi_ut_initialize_buffer (
	acpi_buffer             *buffer,
	ACPI_SIZE               required_length)
{
	acpi_status             status = AE_OK;


	switch (buffer->length) {
	case ACPI_NO_BUFFER:

		/* Set the exception and returned the required length */

		status = AE_BUFFER_OVERFLOW;
		break;


	case ACPI_ALLOCATE_BUFFER:

		/* Allocate a new buffer */

		buffer->pointer = acpi_os_allocate (required_length);
		if (!buffer->pointer) {
			return (AE_NO_MEMORY);
		}

		/* Clear the buffer */

		ACPI_MEMSET (buffer->pointer, 0, required_length);
		break;


	case ACPI_ALLOCATE_LOCAL_BUFFER:

		/* Allocate a new buffer with local interface to allow tracking */

		buffer->pointer = ACPI_MEM_ALLOCATE (required_length);
		if (!buffer->pointer) {
			return (AE_NO_MEMORY);
		}

		/* Clear the buffer */

		ACPI_MEMSET (buffer->pointer, 0, required_length);
		break;


	default:

		/* Validate the size of the buffer */

		if (buffer->length < required_length) {
			status = AE_BUFFER_OVERFLOW;
		}

		/* Clear the buffer */

		ACPI_MEMSET (buffer->pointer, 0, required_length);
		break;
	}

	buffer->length = required_length;
	return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_allocate
 *
 * PARAMETERS:  Size                - Size of the allocation
 *              Component           - Component type of caller
 *              Module              - Source file name of caller
 *              Line                - Line number of caller
 *
 * RETURN:      Address of the allocated memory on success, NULL on failure.
 *
 * DESCRIPTION: The subsystem's equivalent of malloc.
 *
 ******************************************************************************/

void *
acpi_ut_allocate (
	ACPI_SIZE               size,
	u32                     component,
	NATIVE_CHAR             *module,
	u32                     line)
{
	void                    *allocation;


	ACPI_FUNCTION_TRACE_U32 ("Ut_allocate", size);


	/* Check for an inadvertent size of zero bytes */

	if (!size) {
		_ACPI_REPORT_ERROR (module, line, component,
				("Ut_allocate: Attempt to allocate zero bytes\n"));
		size = 1;
	}

	allocation = acpi_os_allocate (size);
	if (!allocation) {
		/* Report allocation error */

		_ACPI_REPORT_ERROR (module, line, component,
				("Ut_allocate: Could not allocate size %X\n", size));

		return_PTR (NULL);
	}

	return_PTR (allocation);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_callocate
 *
 * PARAMETERS:  Size                - Size of the allocation
 *              Component           - Component type of caller
 *              Module              - Source file name of caller
 *              Line                - Line number of caller
 *
 * RETURN:      Address of the allocated memory on success, NULL on failure.
 *
 * DESCRIPTION: Subsystem equivalent of calloc.
 *
 ******************************************************************************/

void *
acpi_ut_callocate (
	ACPI_SIZE               size,
	u32                     component,
	NATIVE_CHAR             *module,
	u32                     line)
{
	void                    *allocation;


	ACPI_FUNCTION_TRACE_U32 ("Ut_callocate", size);


	/* Check for an inadvertent size of zero bytes */

	if (!size) {
		_ACPI_REPORT_ERROR (module, line, component,
				("Ut_callocate: Attempt to allocate zero bytes\n"));
		return_PTR (NULL);
	}

	allocation = acpi_os_allocate (size);
	if (!allocation) {
		/* Report allocation error */

		_ACPI_REPORT_ERROR (module, line, component,
				("Ut_callocate: Could not allocate size %X\n", size));
		return_PTR (NULL);
	}

	/* Clear the memory block */

	ACPI_MEMSET (allocation, 0, size);
	return_PTR (allocation);
}


#ifdef ACPI_DBG_TRACK_ALLOCATIONS
/*
 * These procedures are used for tracking memory leaks in the subsystem, and
 * they get compiled out when the ACPI_DBG_TRACK_ALLOCATIONS is not set.
 *
 * Each memory allocation is tracked via a doubly linked list.  Each
 * element contains the caller's component, module name, function name, and
 * line number.  Acpi_ut_allocate and Acpi_ut_callocate call
 * Acpi_ut_track_allocation to add an element to the list; deletion
 * occurs in the body of Acpi_ut_free.
 */


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_allocate_and_track
 *
 * PARAMETERS:  Size                - Size of the allocation
 *              Component           - Component type of caller
 *              Module              - Source file name of caller
 *              Line                - Line number of caller
 *
 * RETURN:      Address of the allocated memory on success, NULL on failure.
 *
 * DESCRIPTION: The subsystem's equivalent of malloc.
 *
 ******************************************************************************/

void *
acpi_ut_allocate_and_track (
	ACPI_SIZE               size,
	u32                     component,
	NATIVE_CHAR             *module,
	u32                     line)
{
	acpi_debug_mem_block    *allocation;
	acpi_status             status;


	allocation = acpi_ut_allocate (size + sizeof (acpi_debug_mem_block), component,
			  module, line);
	if (!allocation) {
		return (NULL);
	}

	status = acpi_ut_track_allocation (ACPI_MEM_LIST_GLOBAL, allocation, size,
			  ACPI_MEM_MALLOC, component, module, line);
	if (ACPI_FAILURE (status)) {
		acpi_os_free (allocation);
		return (NULL);
	}

	acpi_gbl_memory_lists[ACPI_MEM_LIST_GLOBAL].total_allocated++;
	acpi_gbl_memory_lists[ACPI_MEM_LIST_GLOBAL].current_total_size += (u32) size;

	return ((void *) &allocation->user_space);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_ut_callocate_and_track
 *
 * PARAMETERS:  Size                - Size of the allocation