include/ddekit/memory.h

   1 /*-
   2  * Copyright (c) 2006 Thomas Friebel    <tf13@os.inf.tu-dresden.de>
   3  * Copyright (c) 2006 Christian Helmuth <ch12@os.inf.tu-dresden.de>
   4  * Copyright (c) 2010 Dirk Vogt <dvogt@few.vu.nl>.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  21  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  22  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  23  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  24  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  25  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  26  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  27  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  28  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31 #ifndef _DDEKIT_MEMORY_H
  32 #define _DDEKIT_MEMORY_H
  33
  34 #include <ddekit/ddekit.h>
  35
  36 /*******************
  37  ** Slab facility **
  38  *******************/
  39
  40 struct ddekit_slab;
  41
  42 /* Store user pointer in slab cache */
  43 void ddekit_slab_set_data(struct ddekit_slab * slab, void *data);
  44
  45 /* Read user pointer from slab cache */
  46 void *ddekit_slab_get_data(struct ddekit_slab * slab);
  47
  48 /* Allocate slab in slab cache */
  49 void *ddekit_slab_alloc(struct ddekit_slab * slab);
  50
  51 /* Allocate slab in slab cache */
  52 void ddekit_slab_free(struct ddekit_slab * slab, void *objp);
  53
  54 /*
  55  * Setup page cache for all slabs
  56  *
  57  * pages:  maximal number of memory pages
  58  *
  59  * If 'pages' is too low, memory pages may be given back to the memory server
  60  * (dm_phys) and just to be allocated again later. This hits performance (but
  61  * saves memory). Increase 'pages' to avoid this thrashing-like effect.
  62  *
  63  * If the maximal number of unused pages is exceeded, subsequent deallocation
  64  * will be freed at the memory server. This page cache caches pages from all
  65  * slabs.
  66  */
  67 void ddekit_slab_setup_page_cache(unsigned pages);
  68
  69 /*
  70  * Destroy slab cache
  71  *
  72  * slab:  pointer to slab cache structure
  73  */
  74 void ddekit_slab_destroy(struct ddekit_slab * slab);
  75
  76 /**
  77  * Initialize slab cache
  78  *
  79  * \param size          size of cache objects
  80  * \param contiguous    make this slab use physically contiguous memory
  81  *
  82  * \return pointer to new slab cache or 0 on error
  83  */
  84 struct ddekit_slab * ddekit_slab_init(unsigned size, int contiguous);
  85
  86
  87 /**********************
  88  ** Memory allocator **
  89  **********************/
  90
  91 /*
  92  * Allocate large memory block
  93  *
  94  * \param size  block size
  95  * \return pointer to new memory block
  96  *
  97  * Allocations via this allocator may be slow (because memory servers are
  98  * involved) and should be used only for large (i.e., > page size) blocks. If
  99  * allocations/deallocations are relatively dynamic this may not be what you
 100  * want.
 101  *
 102  * Allocated blocks have valid virt->phys mappings and are physically
 103  * contiguous.
 104  */
 105 void *ddekit_large_malloc(int size);
 106
 107 /**
 108  * Free large memory block
 109  *
 110  * \param p  pointer to memory block
 111  */
 112 void ddekit_large_free(void *p);
 113
 114 /** FIXME
 115  * contig_malloc() is the lowest-level allocator interface one could implement.
 116  * we should consider to provide vmalloc() too. */
 117 void *ddekit_contig_malloc(unsigned long size, unsigned long low,
 118         unsigned long high, unsigned long alignment, unsigned long boundary);
 119
 120
 121 /*****************************
 122  ** Simple memory allocator **
 123  *****************************/
 124
 125 /**
 126  * Allocate memory block via simple allocator
 127  *
 128  * \param size  block size
 129  * \return pointer to new memory block
 130  *
 131  * The blocks allocated via this allocator CANNOT be used for DMA or other
 132  * device operations, i.e., there exists no virt->phys mapping.
 133  */
 134 void *ddekit_simple_malloc(unsigned size);
 135
 136 /**
 137  * Free memory block via simple allocator
 138  *
 139  * \param p  pointer to memory block
 140  */
 141 void ddekit_simple_free(void *p);
 142
 143 #endif