q.h

用于汇编领域的,运用于OS的MAIN函数.基于硬件基础的源代码

#define INIT_COUNTER 300
#define __KERNEL_CS 1<<3
#define __KERNEL_DS 2<<3

struct pt_regs {
	long ebx;
	long ecx;
	long edx;
	long esi;
	long edi;
	long ebp;
	long eax;
	int xds;
	int xes;
	long orig_eax;
	long eip;
	int xcs;
	long eflags;
	long esp;
	int xss;
};
struct task_struct{
    int x,z;
	int state;
	int pid;
	int pptr, cptr; // parent, child
	struct mm_struct * mm; // memory
	//struct FilePtr * fd[20]; // max 20 files opened per process
	struct task_struct * next_task, * prev_task; // process queue
	struct task_struct * next_run, * prev_run; // run queue
	long esp; // stack top
	int y;
	long esp0; // stack top for tss
	long eip; // stopped location
	long counter; // time quantum
	int  need_reschedule;
};

union task_union{
	struct task_struct task;
        long  stack[2048];
}; // 8192 byte for a process

#define IO_BITMAP_SIZE 32
struct tss_struct{
	unsigned short back_link, __blh;
	unsigned long  esp0;
	unsigned short ss0, __ss0h;
	unsigned long  esp1;
	unsigned short ss1,__ss1h;
	unsigned long  esp2;
	unsigned short ss2,__ss2h;
	unsigned long  __cr3;
	unsigned long  eip;
	unsigned long  eflags;
	unsigned long  eax,ecx,edx,ebx;
	unsigned long  esp;
	unsigned long  ebp;
	unsigned long  esi;
	unsigned long  edi;
	unsigned short es, __esh;
	unsigned short cs, __csh;
	unsigned short ss, __ssh;
	unsigned short ds, __dsh;
	unsigned short fs, __fsh;
	unsigned short gs, __gsh;
	unsigned short ldt, __ldth;
	unsigned short trace, bitmap;
	unsigned long  io_bitmap[IO_BITMAP_SIZE+1];
	unsigned long __cacheline_filler[5];
};

struct desc_struct{
	unsigned long a,b;
};


extern union task_union process_table[];
extern union task_union * init_task_union;
extern struct task_struct * current;
extern struct task_struct * init_task;
extern struct task_struct * process_q_head;
extern struct task_struct * process_q_tail;
extern struct task_struct * run_q_head;
extern struct task_struct * run_q_tail;
extern struct task_struct * p1;
extern struct task_struct * p2;
extern struct tss_struct init_tss;
extern struct desc_struct GDT[];

extern void p1_body(struct pt_regs regs);
extern void p2_body();