main.c

一个用于学习的操作系统

/*文件名: main.c
  说明:   内核高级初始化
  作者:   marsinfan
  日期:   2005/12/20
*/

#include <asm/io.h>
#include <asm/system.h>
#include <stdarg.h>
#include <fairysky/types.h>
#include <asm/memory.h>
#include <fairysky/defs.h>
#include <fairysky/string.h>
#include <fairysky/kernel.h>
#include <fairysky/unistd.h>
#include <asm/segment.h>



static inline _syscall0(int, fork)
static inline _syscall3(int, write, int, fd, const char *, buf, off_t, count)
//static inline _syscall1(int, dup, int,fd)
static inline _syscall3(int, open, const char *, file, int, flag, int, mode)
static inline _syscall1(int, close, int, fd)

extern int vsprintf(char *buf, const char *fmt, va_list args);
extern void init_irq(void);
extern void init_sched();
extern void init();
extern int init_hd();

//在内核中取消低4M地址映射
static inline void cancel_mem_map()
{
    u32 *page_dir = (u32 *)PAGE_DIR;
    page_dir[0] = 0;
    __flush_tlb();
}

//设置进程0的堆栈
static inline void mov_task0_stack()
{
    //获取一个空页面，映射到虚拟地址0xC0000000 - PAGE_SIZE处
    if (0 == put_page(0xC0000000 - PAGE_SIZE)) {
        printk("-1\n");
    }
    //复制进程0的堆栈到新的堆栈，复制堆栈可以优化
    memcpy((void *)(0xC0000000 - PAGE_SIZE), (void *)(0xC00A0000 - PAGE_SIZE), PAGE_SIZE);
}

void start_kernel()
{
    cancel_mem_map();   //及早的取消低端的地址映射

    init_tty();

    pparams = (PARAMS_INFO *)paddr_to_vaddr(PARAMS);
    /*printk("cusor_x:%d\n", pparams->cusor_x);
    printk("cusor_y:%d\n", pparams->cusor_y);
    printk("mem_size:%d\n", pparams->mem_size);
//    printk("cusor_x:%d\n", pparams->nouse1);
    printk("display_page:%d\n", pparams->display_page);
//    printk("cusor_x:%d\n", pparams->nouse2);
    printk("video_mode:%d\n", pparams->video_mode);
    printk("window_width:%d\n", pparams->window_width);
//    printk("cusor_x:%d\n", pparams->nouse3);
    printk("vidio_mem_size:%d\n", pparams->vidio_mem_size);
    printk("display_stat:%d\n", pparams->display_stat);
    printk("vidio_param:%d\n", pparams->vidio_param);


    printk("hd_cyl:%d\n", *(u16 *)(pparams->BIOS));
    printk("hd_head:%d\n", *(u8 *)(pparams->BIOS + 2));
    printk("hd_wpcom:%d\n", *(u16 *)(pparams->BIOS + 5));
    printk("hd_ctl:%d\n", *(u8 *)(pparams->BIOS + 8));
    printk("hd_lzone:%d\n", *(u16 *)(pparams->BIOS + 12));
    printk("hd_sect:%d\n", *(u8 *)(pparams->BIOS + 14));   */


    //panic("");

    init_mem();
    init_sched();
    init_irq();
    //init_hd();

    /*trap_init();
    chr_dev_init();
    blk_dev_init();
    mem_init();
    buffer_init();
    time_init();
    hd_init();
    floppy_init();
    sock_init();

    */
    mov_task0_stack();       //设置进程0的堆栈

    //outb_p(0xF8, PORT_8259M + 1);
    //outb_p(0xBF, PORT_8259S + 1);

   // outb_p(inb_p(0x21) & 0xFC, PORT_8259M + 1);
    outb_p(inb_p(0x21) & 0xFC, PORT_8259M + 1);

    //outb_p(inb_p(0x21) & 0xFB, PORT_8259M + 1);
    //outb_p(inb_p(0xA1) & 0xBF, PORT_8259S + 1);

    sti();

    //把进程0返回到特权3下运行，并切换了堆栈的地址
    move_to_user_mode(0xC0000000 - (0xC00A0000 - get_esp()));
    //move_to_user_mode(get_esp() - 0x000A0000);

    if (fork() == 0) {
        init();
    } else {
        //
    }

    for (;;) ;//进程0什么都不做

}