लिनक्स/linux-0.01.tar/include/linux/sched.h
< लिनक्स | linux-0.01.tar
#ifndef _SCHED_H
#define _SCHED_H
#define NR_TASKS 64
#define HZ 100
#define FIRST_TASK task[0]
#define LAST_TASK task[NR_TASKS-1]
#include <linux/head.h>
#include <linux/fs.h>
#include <linux/mm.h>
#if (NR_OPEN > 32)
#error "Currently the close-on-exec-flags are in one word, max 32 files/proc"
#endif
#define TASK_RUNNING 0
#define TASK_INTERRUPTIBLE 1
#define TASK_UNINTERRUPTIBLE 2
#define TASK_ZOMBIE 3
#define TASK_STOPPED 4
#ifndef NULL
#define NULL ((void *) 0)
#endif
extern int copy_page_tables(unsigned long from, unsigned long to, long size);
extern int free_page_tables(unsigned long from, long size);
extern void sched_init(void);
extern void schedule(void);
extern void trap_init(void);
extern void panic(const char * str);
extern int tty_write(unsigned minor,char * buf,int count);
typedef int (*fn_ptr)();
struct i387_struct {
long cwd;
long swd;
long twd;
long fip;
long fcs;
long foo;
long fos;
long st_space[20]; /* 8*10 bytes for each FP-reg = 80 bytes */
};
struct tss_struct {
long back_link; /* 16 high bits zero */
long esp0;
long ss0; /* 16 high bits zero */
long esp1;
long ss1; /* 16 high bits zero */
long esp2;
long ss2; /* 16 high bits zero */
long cr3;
long eip;
long eflags;
long eax,ecx,edx,ebx;
long esp;
long ebp;
long esi;
long edi;
long es; /* 16 high bits zero */
long cs; /* 16 high bits zero */
long ss; /* 16 high bits zero */
long ds; /* 16 high bits zero */
long fs; /* 16 high bits zero */
long gs; /* 16 high bits zero */
long ldt; /* 16 high bits zero */
long trace_bitmap; /* bits: trace 0, bitmap 16-31 */
struct i387_struct i387;
};
struct task_struct {
/* these are hardcoded - don't touch */
long state; /* -1 unrunnable, 0 runnable, >0 stopped */
long counter;
long priority;
long signal;
fn_ptr sig_restorer;
fn_ptr sig_fn[32];
/* various fields */
int exit_code;
unsigned long end_code,end_data,brk,start_stack;
long pid,father,pgrp,session,leader;
unsigned short uid,euid,suid;
unsigned short gid,egid,sgid;
long alarm;
long utime,stime,cutime,cstime,start_time;
unsigned short used_math;
/* file system info */
int tty; /* -1 if no tty, so it must be signed */
unsigned short umask;
struct m_inode * pwd;
struct m_inode * root;
unsigned long close_on_exec;
struct file * filp[NR_OPEN];
/* ldt for this task 0 - zero 1 - cs 2 - ds&ss */
struct desc_struct ldt[3];
/* tss for this task */
struct tss_struct tss;
};
/*
* INIT_TASK is used to set up the first task table, touch at
* your own risk!. Base=0, limit=0x9ffff (=640kB)
*/
#define INIT_TASK \
/* state etc */ { 0,15,15, \
/* signals */ 0,NULL,{(fn_ptr) 0,}, \
/* ec,brk... */ 0,0,0,0,0, \
/* pid etc.. */ 0,-1,0,0,0, \
/* uid etc */ 0,0,0,0,0,0, \
/* alarm */ 0,0,0,0,0,0, \
/* math */ 0, \
/* fs info */ -1,0133,NULL,NULL,0, \
/* filp */ {NULL,}, \
{ \
{0,0}, \
/* ldt */ {0x9f,0xc0fa00}, \
{0x9f,0xc0f200}, \
}, \
/*tss*/ {0,PAGE_SIZE+(long)&init_task,0x10,0,0,0,0,(long)&pg_dir,\
0,0,0,0,0,0,0,0, \
0,0,0x17,0x17,0x17,0x17,0x17,0x17, \
_LDT(0),0x80000000, \
{} \
}, \
}
extern struct task_struct *task[NR_TASKS];
extern struct task_struct *last_task_used_math;
extern struct task_struct *current;
extern long volatile jiffies;
extern long startup_time;
#define CURRENT_TIME (startup_time+jiffies/HZ)
extern void sleep_on(struct task_struct ** p);
extern void interruptible_sleep_on(struct task_struct ** p);
extern void wake_up(struct task_struct ** p);
/*
* Entry into gdt where to find first TSS. 0-nul, 1-cs, 2-ds, 3-syscall
* 4-TSS0, 5-LDT0, 6-TSS1 etc ...
*/
#define FIRST_TSS_ENTRY 4
#define FIRST_LDT_ENTRY (FIRST_TSS_ENTRY+1)
#define _TSS(n) ((((unsigned long) n)<<4)+(FIRST_TSS_ENTRY<<3))
#define _LDT(n) ((((unsigned long) n)<<4)+(FIRST_LDT_ENTRY<<3))
#define ltr(n) __asm__("ltr %%ax"::"a" (_TSS(n)))
#define lldt(n) __asm__("lldt %%ax"::"a" (_LDT(n)))
#define str(n) \
__asm__("str %%ax\n\t" \
"subl %2,%%eax\n\t" \
"shrl $4,%%eax" \
:"=a" (n) \
:"a" (0),"i" (FIRST_TSS_ENTRY<<3))
/*
* switch_to(n) should switch tasks to task nr n, first
* checking that n isn't the current task, in which case it does nothing.
* This also clears the TS-flag if the task we switched to has used
* tha math co-processor latest.
*/
#define switch_to(n) {\
struct {long a,b;} __tmp; \
__asm__("cmpl %%ecx,_current\n\t" \
"je 1f\n\t" \
"xchgl %%ecx,_current\n\t" \
"movw %%dx,%1\n\t" \
"ljmp %0\n\t" \
"cmpl %%ecx,%2\n\t" \
"jne 1f\n\t" \
"clts\n" \
"1:" \
::"m" (*&__tmp.a),"m" (*&__tmp.b), \
"m" (last_task_used_math),"d" _TSS(n),"c" ((long) task[n])); \
}
#define PAGE_ALIGN(n) (((n)+0xfff)&0xfffff000)
#define _set_base(addr,base) \
__asm__("movw %%dx,%0\n\t" \
"rorl $16,%%edx\n\t" \
"movb %%dl,%1\n\t" \
"movb %%dh,%2" \
::"m" (*((addr)+2)), \
"m" (*((addr)+4)), \
"m" (*((addr)+7)), \
"d" (base) \
:"dx")
#define _set_limit(addr,limit) \
__asm__("movw %%dx,%0\n\t" \
"rorl $16,%%edx\n\t" \
"movb %1,%%dh\n\t" \
"andb $0xf0,%%dh\n\t" \
"orb %%dh,%%dl\n\t" \
"movb %%dl,%1" \
::"m" (*(addr)), \
"m" (*((addr)+6)), \
"d" (limit) \
:"dx")
#define set_base(ldt,base) _set_base( ((char *)&(ldt)) , base )
#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , (limit-1)>>12 )
#define _get_base(addr) ({\
unsigned long __base; \
__asm__("movb %3,%%dh\n\t" \
"movb %2,%%dl\n\t" \
"shll $16,%%edx\n\t" \
"movw %1,%%dx" \
:"=d" (__base) \
:"m" (*((addr)+2)), \
"m" (*((addr)+4)), \
"m" (*((addr)+7))); \
__base;})
#define get_base(ldt) _get_base( ((char *)&(ldt)) )
#define get_limit(segment) ({ \
unsigned long __limit; \
__asm__("lsll %1,%0\n\tincl %0":"=r" (__limit):"r" (segment)); \
__limit;})
#endif