mmap/i386/mmap.c

   1 /* Mmap management. */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2009  Free Software Foundation, Inc.
   5  *
   6  *  GRUB 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, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <grub/machine/memory.h>
  21 #include <grub/memory.h>
  22 #include <grub/err.h>
  23 #include <grub/misc.h>
  24 #include <grub/mm.h>
  25
  26
  27 #ifndef GRUB_MMAP_REGISTER_BY_FIRMWARE
  28
  29 void *
  30 grub_mmap_malign_and_register (grub_uint64_t align, grub_uint64_t size,
  31                                int *handle, int type, int flags)
  32 {
  33   grub_uint64_t highestlow = 0;
  34
  35   auto int NESTED_FUNC_ATTR find_hook (grub_uint64_t, grub_uint64_t,
  36                                        grub_uint32_t);
  37   int NESTED_FUNC_ATTR find_hook (grub_uint64_t start, grub_uint64_t rangesize,
  38                                   grub_uint32_t memtype)
  39   {
  40     grub_uint64_t end = start + rangesize;
  41     if (memtype != GRUB_MACHINE_MEMORY_AVAILABLE)
  42       return 0;
  43     if (end > 0x100000)
  44       end = 0x100000;
  45     if (end > start + size
  46         && highestlow < ((end - size) - ((end - size) & (align - 1))))
  47       highestlow = (end - size)  - ((end - size) & (align - 1));
  48     return 0;
  49   }
  50
  51   void *ret;
  52   if (flags & GRUB_MMAP_MALLOC_LOW)
  53     {
  54       /* FIXME: use low-memory mm allocation once it's available. */
  55       grub_mmap_iterate (find_hook);
  56       ret = UINT_TO_PTR (highestlow);
  57     }
  58   else
  59     ret = grub_memalign (align, size);
  60
  61   if (! ret)
  62     {
  63       *handle = 0;
  64       return 0;
  65     }
  66
  67   *handle = grub_mmap_register (PTR_TO_UINT64 (ret), size, type);
  68   if (! *handle)
  69     {
  70       grub_free (ret);
  71       return 0;
  72     }
  73
  74   return ret;
  75 }
  76
  77 void
  78 grub_mmap_free_and_unregister (int handle)
  79 {
  80   struct grub_mmap_region *cur;
  81   grub_uint64_t addr;
  82
  83   for (cur = grub_mmap_overlays; cur; cur = cur->next)
  84     if (cur->handle == handle)
  85       break;
  86
  87   if (! cur)
  88     return;
  89
  90   addr = cur->start;
  91
  92   grub_mmap_unregister (handle);
  93
  94   if (addr >= 0x100000)
  95     grub_free (UINT_TO_PTR (addr));
  96 }
  97
  98 #endif