xv6/main.c
rtm 8148b6ee53 i think my cmpxchg use was wrong in acquire
nesting cli/sti: release shouldn't always enable interrupts
separate setup of lapic from starting of other cpus, so cpu() works earlier
flag to disable locking in console output
make locks work even when curproc==0
(still crashes in clock interrupt)
2006-07-12 11:15:38 +00:00

125 lines
2.9 KiB
C

#include "types.h"
#include "param.h"
#include "mmu.h"
#include "proc.h"
#include "defs.h"
#include "x86.h"
#include "traps.h"
#include "syscall.h"
#include "elf.h"
#include "param.h"
#include "spinlock.h"
extern char edata[], end[];
extern int acpu;
extern char _binary_user1_start[], _binary_user1_size[];
extern char _binary_usertests_start[], _binary_usertests_size[];
extern char _binary_userfs_start[], _binary_userfs_size[];
extern use_printf_lock;
int
main()
{
struct proc *p;
if (acpu) {
cpus[cpu()].clis = 1;
cprintf("an application processor\n");
idtinit(); // CPU's idt
lapic_init(cpu());
lapic_timerinit();
lapic_enableintr();
sti();
scheduler();
}
acpu = 1;
// clear BSS
memset(edata, 0, end - edata);
mp_init(); // just set up apic so cpu() works
use_printf_lock = 1;
cpus[cpu()].clis = 1; // cpu starts as if we had called cli()
cprintf("\nxV6\n\n");
pic_init(); // initialize PIC
kinit(); // physical memory allocator
tvinit(); // trap vectors
idtinit(); // CPU's idt
// create fake process zero
p = &proc[0];
memset(p, 0, sizeof *p);
p->state = WAITING;
p->sz = 4 * PAGE;
p->mem = kalloc(p->sz);
memset(p->mem, 0, p->sz);
p->kstack = kalloc(KSTACKSIZE);
p->tf = (struct Trapframe *) (p->kstack + KSTACKSIZE - sizeof(struct Trapframe));
memset(p->tf, 0, sizeof(struct Trapframe));
p->tf->tf_es = p->tf->tf_ds = p->tf->tf_ss = (SEG_UDATA << 3) | 3;
p->tf->tf_cs = (SEG_UCODE << 3) | 3;
p->tf->tf_eflags = FL_IF;
p->pid = 0;
p->ppid = 0;
setupsegs(p);
mp_startthem();
// turn on timer and enable interrupts on the local APIC
lapic_timerinit();
lapic_enableintr();
// init disk device
//ide_init();
// become interruptable
sti();
p = newproc();
load_icode(p, _binary_usertests_start, (unsigned) _binary_usertests_size);
//load_icode(p, _binary_userfs_start, (unsigned) _binary_userfs_size);
p->state = RUNNABLE;
cprintf("loaded userfs\n");
scheduler();
return 0;
}
void
load_icode(struct proc *p, uint8_t *binary, unsigned size)
{
int i;
struct Elf *elf;
struct Proghdr *ph;
// Check magic number on binary
elf = (struct Elf*) binary;
cprintf("elf %x magic %x\n", elf, elf->e_magic);
if (elf->e_magic != ELF_MAGIC)
panic("load_icode: not an ELF binary");
p->tf->tf_eip = elf->e_entry;
p->tf->tf_esp = p->sz;
// Map and load segments as directed.
ph = (struct Proghdr*) (binary + elf->e_phoff);
for (i = 0; i < elf->e_phnum; i++, ph++) {
if (ph->p_type != ELF_PROG_LOAD)
continue;
cprintf("va %x memsz %d\n", ph->p_va, ph->p_memsz);
if (ph->p_va + ph->p_memsz < ph->p_va)
panic("load_icode: overflow in elf header segment");
if (ph->p_va + ph->p_memsz >= p->sz)
panic("load_icode: icode wants to be above UTOP");
// Load/clear the segment
memcpy(p->mem + ph->p_va, binary + ph->p_offset, ph->p_filesz);
memset(p->mem + ph->p_va + ph->p_filesz, 0, ph->p_memsz - ph->p_filesz);
}
}