static int pf( struct registers *r ) {
cli();
uint32_t cr2 = getCR2();
pde_t *cr3 = (pde_t *) PA2KVA(GET_BASE_ADDRESS(getCR3()));
pte_t *pte = (pte_t *) PA2KVA(GET_BASE_ADDRESS(cr3[ GET_PD_OFFSET(cr2) ]));
kprint( r->errcode & 1 ? "Page level protection\n" : "Page not present\n" );
kprint( r->errcode & 2 ? "Write error\n" : "Read error\n" );
kprint( r->errcode & 4 ? "User mode\n" : "Supervisor mode\n" );
kprint( r->errcode & 8 ? "Reserved bits en 1 en PD\n" : "Reserved bits en 0 en PD\n" );
kprint( r->errcode & 16 ? "Instruction Fetch\n" : "No fue Instruction Fetch\n" );
kprint( "CR2: 0x%x\nDir: 0x%x:0x%x\n", cr2, r->cs, r->eip );
if ( r->cs == USER_CS ) {
kprint( "Matando tarea %d\n", tarea_activa );
matar_tarea( tarea_activa );
}
/*if ( cr2 < KERNEL_MEMMAP ) {
kprint ( "PDE Flags: %x\n", cr3[ GET_PD_OFFSET(cr2) ] & 0xF );
kprint ( "PTE Flags: %x\n", pte[ GET_PT_OFFSET(cr2) ] & 0xF );
if ( r->errcode & 1 ) { // Si estaba presente le arreglo esto.
kprint ( "Arreglando.\n" );
cr3[ GET_PD_OFFSET(cr2) ] |= PAGE_USER | PAGE_RW;
invlpg( GET_BASE_ADDRESS(cr2) );
return 0;
}
}*/
for (;;) hlt();
}
/**
* Called when a pagefault occurs, is in charge of fixing the fault and swapping
* if necessary.
*/
void cPageFault(isrVal_t registers)
{
addr_t page = getCR2();
addr_t page_addr = page & ~(0xFFF);
#ifdef PAGEDBG
printf("PG!\n");
printf("Fault addr: %X\nPage index: %X\n", page, page_addr);
printf("Fault type: %X\n", registers.errCode);
printf("EIP: %X\nESP: %X\nESP: %X\n",
registers.eip, registers.procesp, registers.esp);
printf("eax: %X\tebx: %X\necx: %X\tedx: %X\n",
registers.eax, registers.ebx, registers.ecx, registers.edx);
#endif
if (registers.cs != 0x8 && registers.cs != 0x18)
panic("Incorrect frame!");
if (USER(registers.errCode))
panic("Userspace isn't implemented yet!");
if (RESERVED(registers.errCode))
panic("A reserved bit has been set!\n");
if (PRESENT(registers.errCode))
panic("Illegal operation!");
addr_t pd = getPageDir();
/**
* The data bit only works if a specific bit is set. See intel docs volume 3
* for more information.
*/
if (DATA(registers.errCode))
{
#ifdef PAGEDBG
printf("Trying to access unimplemented data!\n");
#endif
if (WRITE(registers.errCode))
{
#ifdef PAGEDBG
printf("Faulted a write attempt!\n");
printf("Adding page!\n");
#endif
if (USER(registers.errCode))
{
//Add a user page!
}
else
{
#ifdef PAGEDBG
printf("Adding a kernel page!\n");
#endif
if (idx_kernel_space == MAP_NOMAP)
panic("Kernel page map not correctly initialised!");
int ret = page_alloc_page
(idx_kernel_space, page_addr, (void*)pd, FALSE);
if (ret != -E_SUCCESS)
{
printf("ERRCODE: %X\n", -ret);
panic("Couldn't alloc page!");
}
#ifdef PAGEDBG
printf("Phys of %X = %X\n", page, page_phys_addr(page, (void*)pd));
#endif
}
}
else
{
#ifdef PAGEDBG
printf("Faulted a read attempt!\n");
#endif
// Assume the page may be read!
if (idx_kernel_space == MAP_NOMAP)
panic("Kernel page map not correctly initialised!");
int ret = page_alloc_page(idx_kernel_space, page_addr,
(void*)pd, FALSE);
if (ret != -E_SUCCESS)
{
printf("ERRCODE: %X\n", -ret);
panic("Couldn't alloc page!");
}
#ifdef PAGEDBG
printf("Phys of %X = %X\n", page, page_phys_addr(page, (void*)pd));
#endif
}
}
else
{
#ifdef PAGEDBG
panic("Trying to run unimplemented code!\n");
#endif
}
#ifdef UNDEFINED
printf("Page faults currently under construction!\n");
#endif
}
