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   1 /*
   2  * Copyright (c) 1998,1999,2000
   3  *      Traakan, Inc., Los Altos, CA
   4  *      All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice unmodified, this list of conditions, and the following
  11  *    disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 /*
  30  * Project:  NDMJOB
  31  * Ident:    $Id: $
  32  *
  33  * Description:
  34  *      The heap is managed like this:
  35  *
  36  *                      +----------------+
  37  *      table ------>   |     entry      |  <----- heap_top
  38  *                      |    -------     |
  39  *                      |     entry      |
  40  *                      |    -------     |
  41  *                      |     entry      |
  42  *                      |    -------     |
  43  *      allo_ent --->   |     .....      |
  44  *              |       |                |
  45  *              V       |                |
  46  *                      ~                ~
  47  *                      ~                ~
  48  *              ^       |                |
  49  *              |       |                |
  50  *      allo_item--->   |     ....       |
  51  *                      |    -------     |
  52  *                      |     item       |
  53  *                      |    -------     |
  54  *                      |     item       |
  55  *                      |    -------     |
  56  *                      |     item       |
  57  *                      +----------------+  <----- heap_end
  58  *
  59  * n_entry = allo_ent - table;
  60  */
  61
  62
  63 #include "ndmlib.h"
  64
  65
  66
  67
  68 int
  69 ndmfhh_initialize (struct ndmfhheap *fhh)
  70 {
  71         NDMOS_MACRO_ZEROFILL (fhh);
  72
  73         return NDMFHH_RET_OK;
  74 }
  75
  76 int
  77 ndmfhh_commission (struct ndmfhheap *fhh, void *heap, unsigned size)
  78 {
  79         fhh->heap_base = heap;
  80         fhh->heap_size = size;
  81         fhh->heap_end = (char*)heap + size;
  82
  83         /* Align everything */
  84         fhh->heap_top = (void*) (((long)heap + (NDMOS_CONST_ALIGN-1))
  85                                                 &~ (NDMOS_CONST_ALIGN-1));
  86         fhh->heap_bot = (void*)
  87                 ((long)((char*)heap+size) &~ (NDMOS_CONST_ALIGN-1));
  88
  89         ndmfhh_reset (fhh);
  90
  91         return NDMFHH_RET_OK;
  92 }
  93
  94 #define SLOP    32
  95
  96 int
  97 ndmfhh_prepare (struct ndmfhheap *fhh,
  98   int fhtype, int entry_size,
  99   unsigned n_item, unsigned total_size_of_items)
 100 {
 101         void *                  pe;
 102         void *                  pi;
 103         unsigned                items_need;
 104
 105         if (fhh->heap_base == 0)
 106                 return NDMFHH_RET_NO_HEAP;
 107
 108         if (fhh->allo_entry == fhh->heap_top) {
 109                 fhh->fhtype = fhtype;
 110                 fhh->entry_size = entry_size;
 111         } else {
 112                 if (fhh->fhtype != fhtype)
 113                         return NDMFHH_RET_TYPE_CHANGE;
 114
 115                 if (fhh->entry_size != entry_size)
 116                         return NDMFHH_RET_ENTRY_SIZE_MISMATCH;
 117         }
 118
 119         items_need = total_size_of_items + n_item * NDMOS_CONST_ALIGN + SLOP;
 120
 121         pe = (char*)fhh->allo_entry + fhh->entry_size;
 122         pi = (char*)fhh->allo_item - items_need;
 123
 124         if (pe >= pi)
 125                 return NDMFHH_RET_OVERFLOW;
 126
 127         /* it'll fit! */
 128         return NDMFHH_RET_OK;
 129 }
 130
 131 void *
 132 ndmfhh_add_entry (struct ndmfhheap *fhh)
 133 {
 134         void *          p;
 135
 136         p = fhh->allo_entry;
 137         if ((char*)fhh->allo_entry + fhh->entry_size < (char*)fhh->allo_item) {
 138                 fhh->allo_entry = (char *)p + fhh->entry_size;
 139                 return p;
 140         } else {
 141                 return 0;
 142         }
 143
 144 }
 145
 146 void *
 147 ndmfhh_add_item (struct ndmfhheap *fhh, unsigned size)
 148 {
 149         void *          p;
 150
 151         size += (NDMOS_CONST_ALIGN-1);
 152         size &= ~(NDMOS_CONST_ALIGN-1);
 153
 154         p = (char*)fhh->allo_item - size;
 155         if (p > fhh->allo_entry) {
 156                 fhh->allo_item = p;
 157                 return p;
 158         } else {
 159                 return 0;
 160         }
 161 }
 162
 163 void *
 164 ndmfhh_save_item (struct ndmfhheap *fhh, void *item, unsigned size)
 165 {
 166         void *          p;
 167
 168         p = ndmfhh_add_item (fhh, size);
 169         if (p) {
 170                 NDMOS_API_BCOPY (item, p, size);
 171         }
 172         return p;
 173 }
 174
 175 int
 176 ndmfhh_reset (struct ndmfhheap *fhh)
 177 {
 178         fhh->allo_entry = fhh->heap_top;
 179         fhh->allo_item = fhh->heap_bot;
 180
 181         return NDMFHH_RET_OK;
 182 }
 183
 184 int
 185 ndmfhh_get_table (struct ndmfhheap *fhh,
 186   int *fhtype_p, void **table_p, unsigned *n_entry_p)
 187 {
 188         unsigned                n;
 189
 190         *fhtype_p = fhh->fhtype;
 191         *table_p = fhh->heap_top;
 192         n = (char*)fhh->allo_entry - (char*)fhh->heap_top;
 193         if (n > 0)
 194                 n /= fhh->entry_size;
 195
 196         *n_entry_p = n;
 197
 198         return NDMFHH_RET_OK;
 199 }
 200