/**************************************************************************************
 Copyright (c) 2002
      The UbixOS Project

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions, the following disclaimer and the list of authors.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions, the following disclaimer and the list of authors
in the documentation and/or other materials provided with the distribution. Neither the name of the UbixOS Project nor the names of its
contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
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 $Id: freepage.c,v 1.1 2003/04/19 11:31:35 reddawg Exp $
**************************************************************************************/

#include <vmm/paging.h>
#include <vmm/memory.h>

/************************************************************************

Function: void freePage(uLong pageAddr);
Description: This Function Marks The Page As Free
Notes:

07/30/02 - This Was Moved Out Of memory.c Into Here

************************************************************************/
void freePage(uLong pageAddr) {
  int pageIndex = 0x0;
  //Find The Page Index To The Memory Map
  pageIndex = (pageAddr/4096);
  //Check If Page COW Is Greater Then 0 If It Is Dec It If Not Free It
  if (memoryMap[pageIndex].cowCounter == 0) {
    //Set Page As Avail So It Can Be Used Again
    memoryMap[pageIndex].status = memAvail;
    memoryMap[pageIndex].cowCounter = 0x0;
    memoryMap[pageIndex].pid = -2;
    freePages++;
    }
  else {
    //Adjust The COW Counter
    adjustCowCounter(((uLong)memoryMap[pageIndex].pageAddr),-1);
    }
  //Return
  return;
  }