Files
codezero/tasks/mm0/src/arch-arm/mm.c
Bahadir Balban 82a7228d89 Prefaulting of utcb pages seem to work.
Next: fs0 should shmat() on others' utcbs.
2008-03-22 15:57:20 +00:00

73 lines
1.8 KiB
C

/*
* Copyright (C) 2007 Bahadir Balban
*/
#include <arch/mm.h>
#include <task.h>
#include <vm_area.h>
/* Extracts generic protection flags from architecture-specific pte */
unsigned int vm_prot_flags(pte_t pte)
{
unsigned int vm_prot_flags = 0;
unsigned int rw_flags = __MAP_USR_RW_FLAGS & PTE_PROT_MASK;
unsigned int ro_flags = __MAP_USR_RO_FLAGS & PTE_PROT_MASK;
/* Clear non-protection flags */
pte &= PTE_PROT_MASK;;
if (pte == ro_flags)
vm_prot_flags = VM_READ | VM_EXEC;
else if (pte == rw_flags)
vm_prot_flags = VM_READ | VM_WRITE | VM_EXEC;
else
vm_prot_flags = VM_NONE;
return vm_prot_flags;
}
#if defined(DEBUG_FAULT_HANDLING)
void arch_print_fault_params(struct fault_data *fault)
{
printf("%s: Handling %s fault (%s abort) from %d. fault @ 0x%x\n",
__TASKNAME__, (fault->reason & VM_READ) ? "read" : "write",
is_prefetch_abort(fault->kdata->fsr) ? "prefetch" : "data",
fault->task->tid, fault->address);
}
#else
void arch_print_fault_params(struct fault_data *fault) { }
#endif
/*
* PTE STATES:
* PTE type field: 00 (Translation fault)
* PTE type field correct, AP bits: None (Read or Write access fault)
* PTE type field correct, AP bits: RO (Write access fault)
*/
/* Extracts arch-specific fault parameters and puts them into generic format */
void set_generic_fault_params(struct fault_data *fault)
{
unsigned int prot_flags = vm_prot_flags(fault->kdata->pte);
fault->reason = 0;
fault->pte_flags = prot_flags;
if (is_prefetch_abort(fault->kdata->fsr)) {
fault->reason |= VM_READ;
fault->address = fault->kdata->faulty_pc;
} else {
fault->address = fault->kdata->far;
/* Always assume read fault first */
if (prot_flags & VM_NONE)
fault->reason |= VM_READ;
else if (prot_flags & VM_READ)
fault->reason |= VM_WRITE;
else
BUG();
}
arch_print_fault_params(fault);
}