addrmap.h

Go to the documentation of this file.

// See the end of this file for license information.

#ifndef TORSION_ADDRMAP_H
#define TORSION_ADDRMAP_H

#include "arch.h"
#include "virtmem.h"
#include "asm.h"
#include "array.h"


class Address_map {
public:
  unsigned* directory;        
  unsigned* disk_directory;     
//  unsigned* table_entry_counts;   ///< per-table number of entries
  static const unsigned ENTRY_PRESENT = 0x1;
  static const unsigned ENTRY_READ_WRITE = 0x2;
  static const unsigned ENTRY_DIRTY = 0x40;
  static const unsigned DIR_ENTRY_SHIFT = 22;
  static const unsigned TABLE_ENTRY_SHIFT = 12; 
  static const unsigned ENTRY_INDEX_MASK = 0x3ff;
  static const unsigned ENTRIES_PER_TABLE = 1024;
  static const unsigned ENTRY_FRAME_ADDRESS = 0xfffff000;
  static const unsigned PAYLOAD_SHIFT = 1;

  void
  init();

  inline unsigned*
  virtual_to_dir_entry(void* virtual_addr) const {
    unsigned index = ((Address)virtual_addr >> DIR_ENTRY_SHIFT) &
                     ENTRY_INDEX_MASK;
    return directory + index;
  }
  
  inline unsigned
  virtual_to_dir_index(void* virtual_addr) const {
    return ((Address)virtual_addr >> DIR_ENTRY_SHIFT) & ENTRY_INDEX_MASK;
  }

  static inline unsigned*
  virtual_to_table_entry(void* virtual_addr, unsigned* table) {
    unsigned index = ((Address)virtual_addr >> TABLE_ENTRY_SHIFT) &
                     ENTRY_INDEX_MASK;
    return table + index;
  }
  
  unsigned
  get_table_entry(void* virtual_addr);

  bool
  set_table_entry(void* virtual_addr, unsigned entry_value);

  inline void*
  table_entry_to_virtual(unsigned* dir_entry, unsigned* physical_table,
                         unsigned* physical_table_entry) {
    unsigned dir_index = dir_entry - directory;
    unsigned table_index = physical_table_entry - physical_table;
    return (void*)((dir_index << DIR_ENTRY_SHIFT) |
                   (table_index << TABLE_ENTRY_SHIFT));
  }

  static inline unsigned*
  dir_entry_to_table(unsigned* dir_entry) {
    return (unsigned*)(*dir_entry & ENTRY_FRAME_ADDRESS);
  }
  
  inline unsigned*
  dir_index_to_table(unsigned dir_index) {
    unsigned* dir_entry = directory + dir_index;
    return (unsigned*)(*dir_entry & ENTRY_FRAME_ADDRESS);
  }
  
  unsigned*
  virtual_to_table_entry(void* virtual_addr);

  unsigned*
  get_table(unsigned dir_index);

  unsigned*
  clear_table(unsigned* physical_table);

  void
  get_dirty_dir_entries(Array<unsigned*>& dirty_dir_entries);

  inline void
  set_table_block_number(unsigned disk_dir_index,
                         unsigned block_number) {
    disk_directory[disk_dir_index] = block_number;
  }
  
  inline unsigned
  get_table_block_number(unsigned disk_dir_index) {
    return disk_directory[disk_dir_index];
  }

  inline void
  set_table_address(unsigned dir_index, unsigned* physical_table) {
    directory[dir_index] = (Address)physical_table | ENTRY_PRESENT |
                           ENTRY_READ_WRITE;
  }
};

#endif

/* Torsion Operating System, Copyright (C) 2000-2004 Dan Helfman
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details (in the COPYING file).
 * 
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

---

Torsion Operating System, Copyright (C) 2000-2004 Dan Helfman