rom/kernel/kernel_memory.c

   1 /*
   2     Copyright © 2010-2011, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Common memory utility functions
   6     Lang: english
   7 */
   8
   9 #include <aros/debug.h>
  10 #include <exec/execbase.h>
  11 #include <exec/memory.h>
  12 #include <proto/exec.h>
  13
  14 #include <kernel_base.h>
  15
  16 /*
  17  * Create MemHeader structure for the specified RAM region.
  18  * The header will be placed in the beginning of the region itself.
  19  * The header will NOT be added to the memory list!
  20  */
  21 void krnCreateMemHeader(CONST_STRPTR name, BYTE pri, APTR start, IPTR size, ULONG flags)
  22 {
  23     /* The MemHeader itself does not have to be aligned */
  24     struct MemHeader *mh = start;
  25
  26     mh->mh_Node.ln_Succ    = NULL;
  27     mh->mh_Node.ln_Pred    = NULL;
  28     mh->mh_Node.ln_Type    = NT_MEMORY;
  29     mh->mh_Node.ln_Name    = (STRPTR)name;
  30     mh->mh_Node.ln_Pri     = pri;
  31     mh->mh_Attributes      = flags;
  32     /* The first MemChunk needs to be aligned. We do it by adding MEMHEADER_TOTAL. */
  33     mh->mh_First           = start + MEMHEADER_TOTAL;
  34     mh->mh_First->mc_Next  = NULL;
  35     mh->mh_First->mc_Bytes = size - MEMHEADER_TOTAL;
  36
  37     /*
  38      * mh_Lower and mh_Upper are informational only. Since our MemHeader resides
  39      * inside the region it describes, the region includes MemHeader.
  40      */
  41     mh->mh_Lower           = start;
  42     mh->mh_Upper           = start + size;
  43     mh->mh_Free            = mh->mh_First->mc_Bytes;
  44 }
  45
  46 /*
  47  * Create informational MemHeader for ROM region.
  48  * The header will be allocated inside another region, specified by 'ram' parameter.
  49  * It will be not possible to allocate memory from the created MemHeader.
  50  * The header will be added to the memory list.
  51  * This routine uses exec.library/Allocate() for memory allocation, so it is safe
  52  * to use before exec.library and kernel.resource memory management is initialized.
  53  */
  54 struct MemHeader *krnCreateROMHeader(struct MemHeader *ram, CONST_STRPTR name, APTR start, APTR end)
  55 {
  56     struct MemHeader *mh = Allocate(ram, sizeof(struct MemHeader));
  57
  58     if (mh)
  59     {
  60         mh->mh_Node.ln_Type = NT_MEMORY;
  61         mh->mh_Node.ln_Name = (STRPTR)name;
  62         mh->mh_Node.ln_Pri = -128;
  63         mh->mh_Attributes = MEMF_KICK;
  64         mh->mh_First = NULL;
  65         mh->mh_Lower = start;
  66         mh->mh_Upper = end + 1;                 /* end is the last valid address of the region */
  67         mh->mh_Free = 0;                        /* Never allocate from this chunk! */
  68         Enqueue(&SysBase->MemList, &mh->mh_Node);
  69     }
  70
  71     return mh;
  72 }