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#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[];
void proc0init();
// Bootstrap processor starts running C code here.
// This is called main0 not main so that it can have
// a void return type. Gcc can't handle functions named
// main that don't return int. Really.
void
main0(void)
{
int i;
static int bcpu; // cannot be on stack
// clear BSS
memset(edata, 0, end - edata);
// Prevent release() from enabling interrupts.
for(i=0; i<NCPU; i++)
cpus[i].nlock = 1;
mp_init(); // collect info about this machine
bcpu = mp_bcpu();
// switch to bootstrap processor's stack
asm volatile("movl %0, %%esp" : : "r" (cpus[bcpu].mpstack + MPSTACK - 32));
asm volatile("movl %0, %%ebp" : : "r" (cpus[bcpu].mpstack + MPSTACK));
lapic_init(bcpu);
cprintf("\ncpu%d: starting xv6\n\n", cpu());
pinit(); // process table
binit(); // buffer cache
pic_init();
ioapic_init();
kinit(); // physical memory allocator
tvinit(); // trap vectors
idtinit(); // this CPU's interrupt descriptor table
fileinit();
iinit(); // i-node table
// make sure there's a TSS
setupsegs(0);
// initialize I/O devices, let them enable interrupts
console_init();
ide_init();
// start other CPUs
mp_startthem();
// turn on timer
if(ismp)
lapic_timerinit();
else
pit8253_timerinit();
// enable interrupts on the local APIC
lapic_enableintr();
// enable interrupts on this processor.
cpus[cpu()].nlock--;
sti();
// initialize process 0
proc0init();
scheduler();
}
// Additional processors start here.
void
mpmain(void)
{
cprintf("cpu%d: starting\n", cpu());
idtinit(); // CPU's idt
if(cpu() == 0)
panic("mpmain on cpu 0");
lapic_init(cpu());
lapic_timerinit();
lapic_enableintr();
// make sure there's a TSS
setupsegs(0);
cpuid(0, 0, 0, 0, 0); // memory barrier
cpus[cpu()].booted = 1;
// Enable interrupts on this processor.
cpus[cpu()].nlock--;
sti();
scheduler();
}
void
proc0init(void)
{
struct proc *p;
extern uchar _binary_initcode_start[], _binary_initcode_size[];
p = copyproc(0);
p->sz = PAGE;
p->mem = kalloc(p->sz);
p->cwd = igetroot();
memset(&p->tf, 0, sizeof p->tf);
p->tf->es = p->tf->ds = p->tf->ss = (SEG_UDATA << 3) | DPL_USER;
p->tf->cs = (SEG_UCODE << 3) | DPL_USER;
p->tf->eflags = FL_IF;
p->tf->esp = p->sz;
// Push dummy return address to placate gcc.
p->tf->esp -= 4;
*(uint*)(p->mem + p->tf->esp) = 0xefefefef;
p->tf->eip = 0;
memmove(p->mem, _binary_initcode_start, (int)_binary_initcode_size);
safestrcpy(p->name, "initcode", sizeof p->name);
p->state = RUNNABLE;
}
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