/****************************************************************************
* mm/mm_internal.h
*
* Copyright (C) 2007, 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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 MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, 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 DAMAGE.
*
****************************************************************************/
#ifndef __MM_MM_INTERNAL_H
#define __MM_MM_INTERNAL_H
/****************************************************************************
* Included Files
****************************************************************************/
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* If the MCU has a small (16-bit) address capability, then we will use
* a smaller chunk header that contains 16-bit size/offset information.
* We will also use the smaller header on MCUs with wider addresses if
* CONFIG_MM_SMALL is selected. This configuration is common with MCUs
* that have a large FLASH space, but only a tiny internal SRAM.
*/
#ifdef CONFIG_SMALL_MEMORY
/* If the MCU has a small addressing capability, then for the smaller
* chunk header.
*/
# undef CONFIG_MM_SMALL
# define CONFIG_MM_SMALL 1
#endif
/* Chunk Header Definitions *************************************************/
/* These definitions define the characteristics of allocator
*
* MM_MIN_SHIFT is used to define MM_MIN_CHUNK.
* MM_MIN_CHUNK - is the smallest physical chunk that can
* be allocated. It must be at least a large as
* sizeof(struct mm_freenode_s). Larger values may
* improve performance slightly, but will waste memory
* due to quantization losses.
*
* MM_MAX_SHIFT is used to define MM_MAX_CHUNK
* MM_MAX_CHUNK is the largest, contiguous chunk of memory
* that can be allocated. It can range from 16-bytes to
* 4Gb. Larger values of MM_MAX_SHIFT can cause larger
* data structure sizes and, perhaps, minor performance
* losses.
*/
#ifdef CONFIG_MM_SMALL
# define MM_MIN_SHIFT 4 /* 16 bytes */
# define MM_MAX_SHIFT 15 /* 32 Kb */
#else
# define MM_MIN_SHIFT 4 /* 16 bytes */
# define MM_MAX_SHIFT 22 /* 4 Mb */
#endif
/* All other definitions derive from these two */
#define MM_MIN_CHUNK (1 << MM_MIN_SHIFT)
#define MM_MAX_CHUNK (1 << MM_MAX_SHIFT)
#define MM_NNODES (MM_MAX_SHIFT - MM_MIN_SHIFT + 1)
#define MM_GRAN_MASK (MM_MIN_CHUNK-1)
#define MM_ALIGN_UP(a) (((a) + MM_GRAN_MASK) & ~MM_GRAN_MASK)
#define MM_ALIGN_DOWN(a) ((a) & ~MM_GRAN_MASK)
/* An allocated chunk is distinguished from a free chunk by
* bit 31 of the 'preceding' chunk size. If set, then this is
* an allocated chunk.
*/
#ifdef CONFIG_MM_SMALL
# define MM_ALLOC_BIT 0x8000
#else
# define MM_ALLOC_BIT 0x80000000
#endif
#define MM_IS_ALLOCATED(n) \
((int)((struct mm_allocnode_s*)(n)->preceding) < 0))
/****************************************************************************
* Public Types
****************************************************************************/
/* Determine the size of the chunk size/offset type */
#ifdef CONFIG_MM_SMALL
typedef uint16_t mmsize_t;
# define MMSIZE_MAX 0xffff
#else
typedef size_t mmsize_t;
# define MMSIZE_MAX SIZE_MAX
#endif
/* This describes an allocated chunk. An allocated chunk is
* distinguished from a free chunk by bit 15/31 of the 'preceding' chunk
* size. If set, then this is an allocated chunk.
*/
struct mm_allocnode_s
{
mmsize_t size; /* Size of this chunk */
mmsize_t preceding; /* Size of the preceding chunk */
};
/* What is the size of the allocnode? */
#ifdef CONFIG_MM_SMALL
# define SIZEOF_MM_ALLOCNODE 4
#else
# define SIZEOF_MM_ALLOCNODE 8
#endif
#define CHECK_ALLOCNODE_SIZE \
DEBUGASSERT(sizeof(struct mm_allocnode_s) == SIZEOF_MM_ALLOCNODE)
/* This describes a free chunk */
struct mm_freenode_s
{
mmsize_t size; /* Size of this chunk */
mmsize_t preceding; /* Size of the preceding chunk */
FAR struct mm_freenode_s *flink; /* Supports a doubly linked list */
FAR struct mm_freenode_s *blink;
};
/* What is the size of the freenode? */
#ifdef CONFIG_MM_SMALL
# ifdef CONFIG_SMALL_MEMORY
# define SIZEOF_MM_FREENODE 8
# else
# define SIZEOF_MM_FREENODE 12
# endif
#else
# define SIZEOF_MM_FREENODE 16
#endif
#define CHECK_FREENODE_SIZE \
DEBUGASSERT(sizeof(struct mm_freenode_s) == SIZEOF_MM_FREENODE)
/* Normally defined in stdlib.h */
#ifdef MM_TEST
struct mallinfo
{
int arena; /* This is the total size of memory allocated
* for use by malloc in bytes. */
int ordblks; /* This is the number of free (not in use) chunks */
int mxordblk; /* Size of the largest free (not in use) chunk */
int uordblks; /* This is the total size of memory occupied by
* chunks handed out by malloc. */
int fordblks; /* This is the total size of memory occupied
* by free (not in use) chunks.*/
};
#endif
/****************************************************************************
* Global Variables
****************************************************************************/
/* This is the size of the heap provided to mm */
extern size_t g_heapsize;
/* This is the first and last nodes of the heap */
extern FAR struct mm_allocnode_s *g_heapstart[CONFIG_MM_REGIONS];
extern FAR struct mm_allocnode_s *g_heapend[CONFIG_MM_REGIONS];
#if CONFIG_MM_REGIONS > 1
extern int g_nregions;
#else
# define g_nregions 1
#endif
/* All free nodes are maintained in a doubly linked list. This
* array provides some hooks into the list at various points to
* speed searches for free nodes.
*/
extern FAR struct mm_freenode_s g_nodelist[MM_NNODES];
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#ifdef MM_TEST
FAR void *mm_malloc(size_t);
void mm_free(void*);
FAR void *mm_realloc(void*, size_t);
FAR void *mm_memalign(size_t, size_t);
FAR void *mm_zalloc(size_t);
FAR void *mm_calloc(size_t, size_t);
#ifdef CONFIG_CAN_PASS_STRUCTS
struct mallinfo mallinfo(void);
#else
int mallinfo(struct mallinfo *info);
#endif
#endif
void mm_shrinkchunk(FAR struct mm_allocnode_s *node, size_t size);
void mm_addfreechunk(FAR struct mm_freenode_s *node);
int mm_size2ndx(size_t size);
void mm_seminitialize(void);
void mm_takesemaphore(void);
void mm_givesemaphore(void);
#ifdef MM_TEST
int mm_getsemaphore(void);
#endif
#endif /* __MM_MM_INTERNAL_H */
