src/commonlib/mem_pool.c

   1 /*
   2  * This file is part of the coreboot project.
   3  *
   4  * Copyright 2015 Google Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; version 2 of the License.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <commonlib/helpers.h>
  17 #include <commonlib/mem_pool.h>
  18
  19 void *mem_pool_alloc(struct mem_pool *mp, size_t sz)
  20 {
  21         void *p;
  22
  23         /* Make all allocations be at least 8 byte aligned. */
  24         sz = ALIGN_UP(sz, 8);
  25
  26         /* Determine if any space available. */
  27         if ((mp->size - mp->free_offset) < sz)
  28                 return NULL;
  29
  30         p = &mp->buf[mp->free_offset];
  31
  32         mp->free_offset += sz;
  33         mp->last_alloc = p;
  34
  35         return p;
  36 }
  37
  38 void mem_pool_free(struct mem_pool *mp, void *p)
  39 {
  40         /* Determine if p was the most recent allocation. */
  41         if (p == NULL || mp->last_alloc != p)
  42                 return;
  43
  44         mp->free_offset = mp->last_alloc - mp->buf;
  45         /* No way to track allocation before this one. */
  46         mp->last_alloc = NULL;
  47 }