void
intr_routine_page_fault(const isr_param* param)
{
- uintptr_t ptr = cpu_rcr2();
+ uint32_t errcode = param->execp->err_code;
+ ptr_t ptr = cpu_rcr2();
if (!ptr) {
goto segv_term;
}
goto segv_term;
}
- if (!SEL_RPL(param->cs)) {
- // 如果是内核页错误……
- if (do_kernel(&mapping)) {
- return;
- }
- // 如果不是,那么看看内核是不是需要用户页。
+ if (!SEL_RPL(param->execp->cs)) {
+ // TODO if kernel pfault
}
- struct mm_region* hit_region = region_get(&__current->mm.regions, ptr);
+ vm_regions_t* vmr = (vm_regions_t*)&__current->mm.regions;
+ struct mm_region* hit_region = region_get(vmr, ptr);
if (!hit_region) {
// 当你凝视深渊时……
goto segv_term;
}
+ if ((errcode & PG_ALLOW_USER)) {
+ // invalid access
+ goto segv_term;
+ }
+
volatile x86_pte_t* pte = &PTE_MOUNTED(VMS_SELF, ptr >> 12);
if (PG_IS_PRESENT(*pte)) {
if ((hit_region->attr & COW_MASK) == COW_MASK) {
// normal page fault, do COW
- cpu_invplg(pte);
- uintptr_t pa =
- (uintptr_t)vmm_dup_page(__current->pid, PG_ENTRY_ADDR(*pte));
+ cpu_invplg((ptr_t)pte);
+
+ ptr_t pa = (ptr_t)vmm_dup_page(__current->pid, PG_ENTRY_ADDR(*pte));
+
pmm_free_page(__current->pid, *pte & ~0xFFF);
*pte = (*pte & 0xFFF & ~PG_DIRTY) | pa | PG_WRITE;
+
goto resolved;
}
// impossible cases or accessing privileged page
// -> a new page need to be alloc
if ((hit_region->attr & REGION_ANON)) {
if (!PG_IS_PRESENT(*pte)) {
- cpu_invplg(pte);
- uintptr_t pa = pmm_alloc_page(__current->pid, 0);
+ cpu_invplg((ptr_t)pte);
+
+ ptr_t pa = pmm_alloc_page(__current->pid, 0);
if (!pa) {
goto oom;
}
- *pte = *pte | pa | PG_PRESENT;
+ *pte = *pte | pa | PG_PRESENT | PG_ALLOW_USER;
+ memset((void*)PG_ALIGN(ptr), 0, PG_SIZE);
goto resolved;
}
// permission denied on anon page (e.g., write on readonly page)
// if mfile is set (Non-anonymous), then it is a mem map
if (hit_region->mfile && !PG_IS_PRESENT(*pte)) {
struct v_file* file = hit_region->mfile;
- u32_t offset =
- (ptr - hit_region->start) & (PG_SIZE - 1) + hit_region->offset;
- uintptr_t pa = pmm_alloc_page(__current->pid, 0);
+
+ ptr = PG_ALIGN(ptr);
+
+ u32_t mseg_off = (ptr - hit_region->start);
+ u32_t mfile_off = mseg_off + hit_region->foff;
+ ptr_t pa = pmm_alloc_page(__current->pid, 0);
if (!pa) {
goto oom;
}
- cpu_invplg(pte);
- *pte = (*pte & 0xFFF) | pa | PG_PRESENT;
+ cpu_invplg((ptr_t)pte);
+ *pte = (*pte & 0xFFF) | pa | PG_PRESENT | PG_ALLOW_USER;
- ptr = PG_ALIGN(ptr);
- memset(ptr, 0, PG_SIZE);
+ memset((void*)ptr, 0, PG_SIZE);
+
+ int errno = 0;
+ if (mseg_off < hit_region->flen) {
+ errno =
+ file->ops->read_page(file->inode, (void*)ptr, PG_SIZE, mfile_off);
+ }
- int errno = file->ops->read_page(file->inode, ptr, PG_SIZE, offset);
if (errno < 0) {
- kprintf(KERROR "fail to read page (%d)\n", errno);
+ kprintf(KERROR "fail to populate page (%d)\n", errno);
goto segv_term;
}
oom:
kprintf(KERROR "out of memory\n");
+
segv_term:
- kprintf(KERROR "(pid: %d) Segmentation fault on %p (%p:%p)\n",
+ kprintf(KERROR "(pid: %d) Segmentation fault on %p (%p:%p,e=0x%x)\n",
__current->pid,
ptr,
- param->cs,
- param->eip);
+ param->execp->cs,
+ param->execp->eip,
+ param->execp->err_code);
+
__SIGSET(__current->sig_pending, _SIGSEGV);
+
schedule();
// should not reach
while (1)
resolved:
cpu_invplg(ptr);
return;
-}
-
-int
-do_kernel(v_mapping* mapping)
-{
- uintptr_t addr = mapping->va;
-
- // TODO
-
- return 0;
-done:
- return 1;
}
\ No newline at end of file