xv6/main.c
rsc 856e1fc1ad Attempt to clean up newproc somewhat.
Also remove all calls to memcpy in favor of
memmove, which has defined semantics when
the ranges overlap.  The fact that memcpy was
working in console.c to scroll the screen is not
guaranteed by all implementations.
2006-07-16 01:47:40 +00:00

128 lines
3 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 uint8_t _binary_user1_start[], _binary_user1_size[];
extern uint8_t _binary_usertests_start[], _binary_usertests_size[];
extern uint8_t _binary_userfs_start[], _binary_userfs_size[];
extern int use_console_lock;
struct spinlock sillylock; // hold this to keep interrupts disabled
int
main()
{
struct proc *p;
if (acpu) {
cprintf("an application processor\n");
idtinit(); // CPU's idt
lapic_init(cpu());
lapic_timerinit();
lapic_enableintr();
scheduler();
}
acpu = 1;
// clear BSS
memset(edata, 0, end - edata);
mp_init(); // collect info about this machine
acquire(&sillylock);
use_console_lock = 1;
lapic_init(mp_bcpu());
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 = SLEEPING;
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 = copyproc(&proc[0]);
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");
release(&sillylock);
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
memmove(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);
}
}