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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[];
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);
}
}
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