xv6-lab/kernel/sysproc.c
2023-01-25 08:09:06 +00:00

122 lines
1.7 KiB
C

#include "types.h"
#include "riscv.h"
#include "param.h"
#include "defs.h"
#include "memlayout.h"
#include "spinlock.h"
#include "proc.h"
uint64
sys_exit(void)
{
int n;
argint(0, &n);
exit(n);
return 0; // not reached
}
uint64
sys_getpid(void)
{
return myproc()->pid;
}
uint64
sys_fork(void)
{
return fork();
}
uint64
sys_wait(void)
{
uint64 p;
argaddr(0, &p);
return wait(p);
}
uint64
sys_sbrk(void)
{
uint64 addr;
int n;
argint(0, &n);
addr = myproc()->sz;
if(growproc(n) < 0)
return -1;
return addr;
}
uint64
sys_sleep(void)
{
int n;
uint ticks0;
argint(0, &n);
acquire(&tickslock);
ticks0 = ticks;
while(ticks - ticks0 < n){
if(killed(myproc())){
release(&tickslock);
return -1;
}
sleep(&ticks, &tickslock);
}
release(&tickslock);
return 0;
}
#ifdef LAB_PGTBL
#define MAX_ABITS (64)
int
sys_pgaccess(void)
{
char access_bits[MAX_ABITS / 8] = {0};
uint64 base;
int pages;
uint64 mask;
argaddr(0, &base); // void*
argint(1, &pages); // int
argaddr(2, &mask); // void*
if (pages > MAX_ABITS) return -1;
acquire(&myproc()->lock);
for (int page = 0; page < pages; ++ page) {
pte_t* pte = walk(myproc()->pagetable, base + (page << PGSHIFT), 0);
if (*pte & PTE_A) {
*pte &= ~PTE_A;
access_bits[page / 8] |= 1 << (page & 0x7);
}
}
release(&myproc()->lock);
copyout(myproc()->pagetable, mask, access_bits, (pages & 0x7) ? (pages >> 3) + 1 : (pages >> 3));
return 0;
}
#endif
uint64
sys_kill(void)
{
int pid;
argint(0, &pid);
return kill(pid);
}
// return how many clock tick interrupts have occurred
// since start.
uint64
sys_uptime(void)
{
uint xticks;
acquire(&tickslock);
xticks = ticks;
release(&tickslock);
return xticks;
}