mm.h

来自「一个微型操作系统源码」· C头文件 代码 · 共 133 行

/*
 * OSV
 * Copyright (C) 2002 Ciprian DOSOFTEI <[e-mail]>
 * All rights reserved.
 * 
 * http://backster.free.fr/osv
 *
 * This file is part of the OSV project. OSV is free software, also known as
 * "open source"; you can redistribute it and/or modify it under the terms 
 * of the GNU General Public License (GPL), version 2, as published by the Free
 * Software Foundation (FSF). To explore alternate licensing terms, contact 
 * the author at [e-mail] or [phone].
 * 
 * OSV 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 GPL for more details.  You should have
 * received a copy of the GPL along with OSV; see the file COPYING.  If
 * not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
 */

#ifndef INCMM
#define INCMM

#include <sys/params.h>
#include <asm/system.h>		/* set_CR0(), set_CR3() etc. */
#include <types.h>

/* support 4GB of RAM (you can change this to reduce size) 
#define MAX_MEMORY 1024*1024*1024 */

#define OWNER_NOBODY	0 
#define OWNER_KERNEL	1

/* Paging constants */
#define PAGE_SIZE       4096

#define PAGE_SHIFT      12
#define PAGE_MASK       0x03FF

#define PDE_SHIFT	22
#define PTE_SHIFT	12

#define TABLE_ENTRIES	1024

#define PAGE_ROUND(x) 	  ((x) & 0xFFFFF000)
#define PAGE_ROUND_UP(x)  (((ulong)(((x)+PAGE_SIZE-1)>>PAGE_SHIFT))<<PAGE_SHIFT)
#define ROUND_4(x) 	  (( x + 3) & ~ 3)

// structure that defines an entry in the pagedir
typedef struct
{
    uint present:1;
    uint readWrite:1;
    uint user:1;
    uint reserved1:2;
    uint accessed:1;
    uint dirty:1;
    uint reserved2:2;
    uint os_use:3; /* for system programmer's use */
    uint address:20;
} pde;

// structure that defines an entry in the pagetable
typedef struct
{
    uint present:1;
    uint readWrite:1;
    uint user:1;
    uint reserved1:2;
    uint accessed:1;
    uint dirty:1;
    uint reserved2:2;
    uint os_use:3; /* for system programmer's use */
    uint address:20;
} pte;

/* values for attrib entry in the structure above */
#define VMM_FREE	0x000
#define VMM_BUSY	0x001
#define VMM_LOCK	0x002

// define a pagedir as an array containig 1024 entries
typedef struct
{
    pde entry[TABLE_ENTRIES];
} pagedir;

extern pagedir *PD;

// define a pagetable as an array containig 1024 entries
typedef struct
{
    pte entry[TABLE_ENTRIES];
} pagetable;

/* Paging and VM functions */
int  setupPaging(ulong availableMemory);
void  enablePaging(void);

void __inline__ make_pde(pagedir *dir, uint nr, ulong addr , uchar attr);
void __inline__ make_pte(pagetable *tab, uint nr, ulong addr , uchar attr);

/* Physical MM  */
void setupMemory(ulong availableMemory, ulong usedMemory);

/* pointers */
typedef struct __memlink
{
    struct __memlink *pNext;
    struct __memlink *pPrev;
    ulong   size;
    ulong   owner;
} memlink;

void *physAlloc(size_t allocsize,ulong client);
void physFree(void *pointer);
void showFreeMemory(void);
void showUsedMemory(void);

void *kmalloc(size_t allocsize);
void kfree(void *pointer);

/* Virtual Memory */
void vmMapInit(pagedir *pd, ulong pages);
int vmKernelMap(pagedir *pd);
int vmMap(pagedir *pd, void *page, ulong attr);
int vmUnmap(pagedir *pd, void *page);
int vmMapRange(pagedir *pd, void *start, size_t len, ulong attr);
int vmUnmapRange(pagedir *pd, void *start, size_t len);
void dumpPageDir(pagedir *pd, ulong pdes);

#endif