You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
133 lines
5.4 KiB
133 lines
5.4 KiB
#ifndef __KERN_MM_MEMLAYOUT_H__
|
|
#define __KERN_MM_MEMLAYOUT_H__
|
|
|
|
/* This file contains the definitions for memory management in our OS. */
|
|
|
|
/* global segment number */
|
|
#define SEG_KTEXT 1
|
|
#define SEG_KDATA 2
|
|
#define SEG_UTEXT 3
|
|
#define SEG_UDATA 4
|
|
#define SEG_TSS 5
|
|
|
|
/* global descrptor numbers */
|
|
#define GD_KTEXT ((SEG_KTEXT) << 3) // kernel text
|
|
#define GD_KDATA ((SEG_KDATA) << 3) // kernel data
|
|
#define GD_UTEXT ((SEG_UTEXT) << 3) // user text
|
|
#define GD_UDATA ((SEG_UDATA) << 3) // user data
|
|
#define GD_TSS ((SEG_TSS) << 3) // task segment selector
|
|
|
|
#define DPL_KERNEL (0)
|
|
#define DPL_USER (3)
|
|
|
|
#define KERNEL_CS ((GD_KTEXT) | DPL_KERNEL)
|
|
#define KERNEL_DS ((GD_KDATA) | DPL_KERNEL)
|
|
#define USER_CS ((GD_UTEXT) | DPL_USER)
|
|
#define USER_DS ((GD_UDATA) | DPL_USER)
|
|
|
|
/* *
|
|
* Virtual memory map: Permissions
|
|
* kernel/user
|
|
*
|
|
* 4G ------------------> +---------------------------------+
|
|
* | |
|
|
* | Empty Memory (*) |
|
|
* | |
|
|
* +---------------------------------+ 0xFB000000
|
|
* | Cur. Page Table (Kern, RW) | RW/-- PTSIZE
|
|
* VPT -----------------> +---------------------------------+ 0xFAC00000
|
|
* | Invalid Memory (*) | --/--
|
|
* KERNTOP -------------> +---------------------------------+ 0xF8000000
|
|
* | |
|
|
* | Remapped Physical Memory | RW/-- KMEMSIZE
|
|
* | |
|
|
* KERNBASE ------------> +---------------------------------+ 0xC0000000
|
|
* | |
|
|
* | |
|
|
* | |
|
|
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
* (*) Note: The kernel ensures that "Invalid Memory" is *never* mapped.
|
|
* "Empty Memory" is normally unmapped, but user programs may map pages
|
|
* there if desired.
|
|
*
|
|
* */
|
|
|
|
/* All physical memory mapped at this address */
|
|
#define KERNBASE 0xC0000000
|
|
#define KMEMSIZE 0x38000000 // the maximum amount of physical memory
|
|
#define KERNTOP (KERNBASE + KMEMSIZE)
|
|
|
|
/* *
|
|
* Virtual page table. Entry PDX[VPT] in the PD (Page Directory) contains
|
|
* a pointer to the page directory itself, thereby turning the PD into a page
|
|
* table, which maps all the PTEs (Page Table Entry) containing the page mappings
|
|
* for the entire virtual address space into that 4 Meg region starting at VPT.
|
|
* */
|
|
#define VPT 0xFAC00000
|
|
|
|
#define KSTACKPAGE 2 // # of pages in kernel stack
|
|
#define KSTACKSIZE (KSTACKPAGE * PGSIZE) // sizeof kernel stack
|
|
|
|
#ifndef __ASSEMBLER__
|
|
|
|
#include <defs.h>
|
|
#include <atomic.h>
|
|
#include <list.h>
|
|
|
|
typedef uintptr_t pte_t;
|
|
typedef uintptr_t pde_t;
|
|
typedef pte_t swap_entry_t; //the pte can also be a swap entry
|
|
|
|
// some constants for bios interrupt 15h AX = 0xE820
|
|
#define E820MAX 20 // number of entries in E820MAP
|
|
#define E820_ARM 1 // address range memory
|
|
#define E820_ARR 2 // address range reserved
|
|
|
|
struct e820map {
|
|
int nr_map;
|
|
struct {
|
|
uint64_t addr;
|
|
uint64_t size;
|
|
uint32_t type;
|
|
} __attribute__((packed)) map[E820MAX];
|
|
};
|
|
|
|
/* *
|
|
* struct Page - Page descriptor structures. Each Page describes one
|
|
* physical page. In kern/mm/pmm.h, you can find lots of useful functions
|
|
* that convert Page to other data types, such as phyical address.
|
|
* */
|
|
struct Page {
|
|
int ref; // page frame's reference counter
|
|
uint32_t flags; // array of flags that describe the status of the page frame
|
|
unsigned int property; // the num of free block, used in first fit pm manager
|
|
list_entry_t page_link; // free list link
|
|
list_entry_t pra_page_link; // used for pra (page replace algorithm)
|
|
uintptr_t pra_vaddr; // used for pra (page replace algorithm)
|
|
};
|
|
|
|
/* Flags describing the status of a page frame */
|
|
#define PG_reserved 0 // the page descriptor is reserved for kernel or unusable
|
|
#define PG_property 1 // the member 'property' is valid
|
|
|
|
#define SetPageReserved(page) set_bit(PG_reserved, &((page)->flags))
|
|
#define ClearPageReserved(page) clear_bit(PG_reserved, &((page)->flags))
|
|
#define PageReserved(page) test_bit(PG_reserved, &((page)->flags))
|
|
#define SetPageProperty(page) set_bit(PG_property, &((page)->flags))
|
|
#define ClearPageProperty(page) clear_bit(PG_property, &((page)->flags))
|
|
#define PageProperty(page) test_bit(PG_property, &((page)->flags))
|
|
|
|
// convert list entry to page
|
|
#define le2page(le, member) \
|
|
to_struct((le), struct Page, member)
|
|
|
|
/* free_area_t - maintains a doubly linked list to record free (unused) pages */
|
|
typedef struct {
|
|
list_entry_t free_list; // the list header
|
|
unsigned int nr_free; // # of free pages in this free list
|
|
} free_area_t;
|
|
|
|
#endif /* !__ASSEMBLER__ */
|
|
|
|
#endif /* !__KERN_MM_MEMLAYOUT_H__ */
|
|
|