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     /* If the end is less than (1 << 31), MEMF_31BIT is implied */
  27     if (((IPTR)start+size) < (1UL << 31))
  28         flags |= MEMF_31BIT;
  29     else
  30         flags &= ~MEMF_31BIT;
  31
  32     mh->mh_Node.ln_Succ    = NULL;
  33     mh->mh_Node.ln_Pred    = NULL;
  34     mh->mh_Node.ln_Type    = NT_MEMORY;
  35     mh->mh_Node.ln_Name    = (STRPTR)name;
  36     mh->mh_Node.ln_Pri     = pri;
  37     mh->mh_Attributes      = flags;
  38     /* The first MemChunk needs to be aligned. We do it by adding MEMHEADER_TOTAL. */
  39     mh->mh_First           = start + MEMHEADER_TOTAL;
  40     mh->mh_First->mc_Next  = NULL;
  41     mh->mh_First->mc_Bytes = size - MEMHEADER_TOTAL;
  42
  43     /*
  44      * mh_Lower and mh_Upper are informational only. Since our MemHeader resides
  45      * inside the region it describes, the region includes MemHeader.
  46      */
  47     mh->mh_Lower           = start;
  48     mh->mh_Upper           = start + size;
  49     mh->mh_Free            = mh->mh_First->mc_Bytes;
  50 }
  51
  52 /*
  53  * Create informational MemHeader for ROM region.
  54  * The header will be allocated from system's public memory lists.
  55  * It will be not possible to allocate memory from the created MemHeader.
  56  * The header will be added to the memory list.
  57  * This routine uses exec.library/Allocate() for memory allocation, so it is safe
  58  * to use before exec.library and kernel.resource memory management is initialized.
  59  */
  60 struct MemHeader *krnCreateROMHeader(CONST_STRPTR name, APTR start, APTR end)
  61 {
  62     struct MemHeader *mh = AllocMem(sizeof(struct MemHeader), MEMF_ANY);
  63
  64     if (mh)
  65     {
  66         mh->mh_Node.ln_Type = NT_MEMORY;
  67         mh->mh_Node.ln_Name = (STRPTR)name;
  68         mh->mh_Node.ln_Pri = -128;
  69         mh->mh_Attributes = MEMF_KICK;
  70         mh->mh_First = NULL;
  71         mh->mh_Lower = start;
  72         mh->mh_Upper = end + 1;                 /* end is the last valid address of the region */
  73         mh->mh_Free = 0;                        /* Never allocate from this chunk! */
  74         Enqueue(&SysBase->MemList, &mh->mh_Node);
  75     }
  76
  77     return mh;
  78 }