memory.h

fairysky系统,是一个小型的内核,模拟linux原始版本的

/*文件名: memory.h
  说明:   页级内存管理函数
  作者:   marsinfan
  日期:   2005/12/20
*/
#ifndef _memory_h_
#define _memory_h_

#include <fairysky/types.h>

#define PAGE_SIZE 4096

#define PAGE_PRESENT	0x001
#define PAGE_RW		0x002
#define PAGE_USER	0x004
#define PAGE_PWT	0x008	/* 486 only - not used currently */
#define PAGE_PCD	0x010	/* 486 only - not used currently */
#define PAGE_ACCESSED	0x020
#define PAGE_DIRTY	0x040
#define PAGE_COW	0x200	/* implemented in software (one of the AVL bits) */

#define PAGE_PRIVATE	(PAGE_PRESENT | PAGE_RW | PAGE_USER | PAGE_ACCESSED | PAGE_COW)
#define PAGE_SHARED	(PAGE_PRESENT | PAGE_RW | PAGE_USER | PAGE_ACCESSED)
#define PAGE_COPY	(PAGE_PRESENT | PAGE_USER | PAGE_ACCESSED | PAGE_COW)
#define PAGE_READONLY	(PAGE_PRESENT | PAGE_USER | PAGE_ACCESSED)
#define PAGE_TABLE	(PAGE_PRESENT | PAGE_RW | PAGE_USER | PAGE_ACCESSED)

extern s32 put_page(addr_t addr);
extern s32 copy_page_table(u32 to, u32 from);
extern void do_wp_page(u32 addr);
extern void do_no_page(u32 addr);
extern int get_free_page();
extern int free_page(u32 addr);

//用刷新cr3的方法来刷新TLB    
#define __flush_tlb()							\
    do {                                \
        unsigned int tmpreg;                    \
        __asm__ __volatile__(                    \
        "movl %%cr3, %0;              \n"        \
        "movl %0, %%cr3;  # flush TLB \n"        \
        : "=r" (tmpreg)                    \
        :: "memory");                    \
        } while (0)


#endif