void gp_fault(unsigned long cs, unsigned long eip, unsigned long error)
{
ReversibleString<256> s;
Formatter::fPrintf(&s, "General Protection Fault (%x) at %x:%x", error, cs, eip);
a.Panic(s.GetString());
}
void VirtMemManager::ResolvePageFault(uintptr fault_address, bool write_error, bool protection_error, bool user_mode)
{
// If its a page not present fault, check for a matching section
if(!protection_error) {
int i, c;
c = CurrentThread->proc->Sections->Count();
Section::Extent ae;
ae.Lower = fault_address;
ae.Upper = fault_address;
protection_error = true; // Set this back to false if we find a valid section
for(i = 0; i < c; i++) {
Section::Extent se;
Section &s = CurrentThread->proc->Sections->GetItem(i);
if(s.CheckExtents(&se)) {
if(ae == se) {
// Its part of this section. Allow expanding sections
if(s.Flags & Section::AutoExpand) {
if((fault_address < s.Base) && ((s.Base - fault_address) <= s.ExpandDown)) {
s.ExpandDown -= (s.Base - fault_address);
s.Base = fault_address;
protection_error = false;
}
if((fault_address >= (s.Base + s.Length)) && ((fault_address - (s.Base + s.Length)) <= s.ExpandUp)) {
s.ExpandUp -= (fault_address - (s.Base + s.Length));
s.Length = fault_address - s.Base + 1;
protection_error = false;
}
}
if((fault_address >= s.Base) && (fault_address < (s.Base + s.Length)))
protection_error = false;
if(!protection_error) {
// Map the page
physaddr_t paddr = NULL;
if(s.Flags & Section::Bits)
paddr = (fault_address - s.Base + s.MemSource) & GetPageMask();
MapPage(fault_address & GetPageMask(), NULL, false, NULL,
(fault_address - s.Base + s.MemSource) & GetPageMask(),
(s.Flags & Section::KernelSection) ? false : true,
(s.Flags & Section::Write) ? true : false);
break;
}
}
}
}
}
// Check for errors
if(protection_error) {
// A bad error
a.kconsole->Printf("PAGE FAULT! Invalid attempt by ");
if(user_mode)
a.kconsole->Printf("process ");
else
a.kconsole->Printf("kernel ");
a.kconsole->Printf("to ");
if(write_error)
a.kconsole->Printf("write to ");
else
a.kconsole->Printf("read from ");
a.kconsole->Printf("address %x whilst executing %s\n", fault_address, CurrentThread->proc->name);
a.Panic();
}
}