210 lines
6.1 KiB
C
210 lines
6.1 KiB
C
/*******************************************************************************/
|
|
/* COS2000 - Compatible Operating System - LGPL v3 - Hordé Nicolas */
|
|
/* */
|
|
|
|
#include "types.h"
|
|
#include "process.h"
|
|
#include "memory.h"
|
|
#include "gdt.h"
|
|
|
|
process *processes;
|
|
process *current;
|
|
u32 lastpid;
|
|
|
|
|
|
static u8 elf_errors1[]="Aucune signature ELF";
|
|
static u8 elf_errors2[]="Fichier au format ELF mais non 32 bits";
|
|
static u8 elf_errors3[]="ELF non LSB";
|
|
static u8 elf_errors4[]="ELF mauvaise version";
|
|
static u8 elf_errors5[]="ELF pour OS ne correspondant pas";
|
|
static u8 elf_errors6[]="Mauvais type de machine";
|
|
static u8 *elf_errors[]={&elf_errors1,&elf_errors2,&elf_errors3,&elf_errors4,&elf_errors5,&elf_errors6};
|
|
|
|
/*******************************************************************************/
|
|
/* Vérifie la signature ELF
|
|
0 - RAS
|
|
1 - Pas la signature ELF
|
|
2 - pas ELF32
|
|
3 - pas bon organisation LSB/MSB
|
|
4 - pas bonne version ELF
|
|
5 - pas bon OS
|
|
6 - pas bon type machine */
|
|
|
|
u32 elf_test(u8 *src)
|
|
{
|
|
elf32 *header=(elf32 *) src;
|
|
if (header->e_ident[EI_MAG0] == ELFMAG0 && header->e_ident[EI_MAG1] == ELFMAG1
|
|
&& header->e_ident[EI_MAG2] == ELFMAG2 && header->e_ident[EI_MAG3] == ELFMAG3)
|
|
{
|
|
if (header->e_ident[EI_CLASS]!=ELFCLASS32)
|
|
return 2;
|
|
if (header->e_ident[EI_DATA]!=ELFDATA2LSB)
|
|
return 3;
|
|
if (header->e_ident[EI_VERSION]!=EV_CURRENT || header->e_version!=EV_CURRENT)
|
|
return 4;
|
|
if (header->e_ident[EI_OSABI]!=ELFOSABI_COS2000)
|
|
return 5;
|
|
if (header->e_machine!=EM_386)
|
|
return 6;
|
|
return 0;
|
|
}
|
|
else
|
|
return 1;
|
|
}
|
|
|
|
/*******************************************************************************/
|
|
/* Charge le fichier ELF en mémoire et mets à jour les informations sur le processus */
|
|
|
|
u32 elf_load(u8 *src, u32 pid)
|
|
{
|
|
u8 *ptr;
|
|
u8 code;
|
|
u32 v_begin, v_end;
|
|
elf32 *header;
|
|
elf32p *program;
|
|
u32 i;
|
|
|
|
header = (elf32 *) src;
|
|
program = (elf32p *) (src + header->e_phoff);
|
|
code=elf_test(src);
|
|
if (code!=0) {
|
|
printf("Erreur de chargement ELF, %s !\r\n",elf_errors[code-1]);
|
|
return NULL;
|
|
}
|
|
for (i = 0; i < header->e_phnum; i++, program++) {
|
|
if (program->p_type == PT_LOAD) {
|
|
v_begin = program->p_vaddr;
|
|
v_end = program->p_vaddr + program->p_memsz;
|
|
if (v_begin < USER_CODE) {
|
|
printf ("Ne peut charger l'executable en desssous de l'adresse %X\r\n", USER_CODE);
|
|
return 0;
|
|
}
|
|
if (v_end > USER_STACK) {
|
|
printf ("Ne peut charger l'executable au desssus de l'adresse %X\r\n", USER_STACK);
|
|
return 0;
|
|
}
|
|
if (program->p_flags == PF_X + PF_R) {
|
|
processes[pid].exec_low = (u8*) v_begin;
|
|
processes[pid].exec_high = (u8*) v_end;
|
|
}
|
|
if (program->p_flags == PF_W + PF_R) {
|
|
processes[pid].bss_low = (u8*) v_begin;
|
|
processes[pid].bss_high = (u8*) v_end;
|
|
}
|
|
memcpy((u8 *) (src + program->p_offset),(u8 *) v_begin , program->p_filesz,0);
|
|
if (program->p_memsz > program->p_filesz)
|
|
for (i = program->p_filesz, ptr = (u8 *) program->p_vaddr; i < program->p_memsz; i++)
|
|
ptr[i] = 0;
|
|
}
|
|
}
|
|
processes[pid].entry=header->e_entry;
|
|
return header->e_entry;
|
|
}
|
|
|
|
/*******************************************************************************/
|
|
/* Initialise la liste des processus */
|
|
|
|
void task_init() {
|
|
u32 i=0;
|
|
processes=(process*)vmalloc(sizeof(process)*MAXNUMPROCESS);
|
|
while (i++ < MAXNUMPROCESS) {
|
|
processes[i].pid=NULL;
|
|
processes[i].status=STATUS_FREE;
|
|
}
|
|
current=NULL;
|
|
lastpid=NULL;
|
|
}
|
|
|
|
/*******************************************************************************/
|
|
/* Récupère un emplacement dans la liste des processus */
|
|
|
|
u32 task_getfreePID ()
|
|
{
|
|
u32 i = lastpid;
|
|
u32 parsed = 0;
|
|
while (processes[++i].status != STATUS_FREE && ++parsed < MAXNUMPROCESS)
|
|
{
|
|
if (i>=MAXNUMPROCESS)
|
|
i=0;
|
|
}
|
|
if (parsed>MAXNUMPROCESS) {
|
|
printf("PANIC: plus d'emplacement disponible pour un novueau processus\n");
|
|
return NULL;
|
|
}
|
|
return i;
|
|
}
|
|
|
|
/*******************************************************************************/
|
|
/* Récupère les informations sur le processus courant */
|
|
process *getcurrentprocess()
|
|
{
|
|
return current;
|
|
}
|
|
|
|
/*******************************************************************************/
|
|
/* Determine le dernier PID occupé */
|
|
|
|
u32 task_usePID (u32 pid)
|
|
{
|
|
lastpid=pid;
|
|
}
|
|
|
|
/*******************************************************************************/
|
|
/* Execute une tâche */
|
|
|
|
void task_run(u32 pid)
|
|
{
|
|
processes[pid].status = STATUS_RUN;
|
|
}
|
|
|
|
/*******************************************************************************/
|
|
/* Initialise une tâche */
|
|
|
|
u32 task_create(u8 *code)
|
|
{
|
|
process *previous=current;
|
|
u32 pid=task_getfreePID();
|
|
task_usePID(pid);
|
|
page *kstack;
|
|
processes[pid].pid = pid;
|
|
processes[pid].pdd = virtual_pd_create();
|
|
TAILQ_INIT(&processes[pid].page_head);
|
|
current = &processes[pid];
|
|
setcr3(processes[pid].pdd->addr->paddr);
|
|
kstack = virtual_page_getfree();
|
|
processes[pid].dump.ss = SEL_USER_STACK | RPL_RING3;
|
|
processes[pid].dump.esp = USER_STACK;
|
|
processes[pid].dump.eflags = 0x0;
|
|
processes[pid].dump.cs = SEL_USER_CODE | RPL_RING3;
|
|
processes[pid].dump.eip = elf_load(code,pid);
|
|
if (processes[pid].dump.eip==NULL)
|
|
return NULL;
|
|
processes[pid].dump.ds = SEL_USER_DATA | RPL_RING3;
|
|
processes[pid].dump.es = SEL_USER_DATA | RPL_RING3;
|
|
processes[pid].dump.fs = SEL_USER_DATA | RPL_RING3;
|
|
processes[pid].dump.gs = SEL_USER_DATA | RPL_RING3;
|
|
processes[pid].dump.cr3 = (u32) processes[pid].pdd->addr->paddr;
|
|
processes[pid].kstack.ss0 = SEL_KERNEL_STACK;
|
|
processes[pid].kstack.esp0 = (u32) kstack->vaddr + PAGESIZE - 16;
|
|
processes[pid].dump.eax = 0;
|
|
processes[pid].dump.ecx = 0;
|
|
processes[pid].dump.edx = 0;
|
|
processes[pid].dump.ebx = 0;
|
|
processes[pid].dump.ebp = 0;
|
|
processes[pid].dump.esi = 0;
|
|
processes[pid].dump.edi = 0;
|
|
processes[pid].result = 0;
|
|
processes[pid].status = STATUS_READY;
|
|
current = previous;
|
|
if (current==NULL)
|
|
{
|
|
u32 pd = KERNEL_PD_ADDR;
|
|
setcr3(pd);
|
|
}
|
|
else
|
|
{
|
|
setcr3(current->dump.cr3);
|
|
}
|
|
return pid;
|
|
}
|