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/*
* This file is part of the coreboot project.
*
* Copyright 2015 Google Inc.
*
* 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; version 2 of the License.
*
* 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.
*/
#ifndef _MEM_POOL_H_
#define _MEM_POOL_H_
#include <stddef.h>
#include <stdint.h>
/*
* The memory pool allows one to allocate memory from a fixed size buffer
* that also allows freeing semantics for reuse. However, the current
* limitation is that the most recent allocation is the only one that
* can be freed. If one tries to free any allocation that isn't the
* most recently allocated it will result in a leak within the memory pool.
*
* The memory returned by allocations are at least 8 byte aligned. Note
* that this requires the backing buffer to start on at least an 8 byte
* alignment.
*/
struct mem_pool {
uint8_t *buf;
size_t size;
uint8_t *last_alloc;
size_t free_offset;
};
#define MEM_POOL_INIT(buf_, size_) \
{ \
.buf = (buf_), \
.size = (size_), \
.last_alloc = NULL, \
.free_offset = 0, \
}
static inline void mem_pool_reset(struct mem_pool *mp)
{
mp->last_alloc = NULL;
mp->free_offset = 0;
}
/* Initialize a memory pool. */
static inline void mem_pool_init(struct mem_pool *mp, void *buf, size_t sz)
{
mp->buf = buf;
mp->size = sz;
mem_pool_reset(mp);
}
/* Allocate requested size from the memory pool. NULL returned on error. */
void *mem_pool_alloc(struct mem_pool *mp, size_t sz);
/* Free allocation from memory pool. */
void mem_pool_free(struct mem_pool *mp, void *alloc);
#endif /* _MEM_POOL_H_ */
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