void map_pages(uint32_t physical_address, uint32_t virtual_address, uint32_t size, uint32_t protect = PT_PRESENT | PT_WRITABLE | PT_USER)
{
int pages = SIZE_TO_PAGES(size);
for (int i = 0; i < pages; i++)
{
UINT32 pde_index = PDE_INDEX(virtual_address);
UINT32 pte_index = PTE_INDEX(virtual_address);
UINT32* page_table = (UINT32*)(PAGE_TABLE_PHYSICAL_ADDR + pde_index*PAGE_SIZE);
page_table[pte_index] = physical_address | protect;
physical_address += PAGE_SIZE;
virtual_address += PAGE_SIZE;
}
}
static void pt_map(pmap_t *pmap, vm_addr_t vaddr, pm_addr_t paddr,
uint8_t flags) {
pde_map(pmap, vaddr);
pte_t entry = flags;
uint32_t pt_index = PTE_INDEX(vaddr);
ENTRYLO_SET_PADDR(entry , paddr);
pmap->pte[pt_index] = entry;
/* invalidate proper entry in tlb */
tlbhi_t entryhi = 0;
ENTRYHI_SET_VADDR(entryhi, vaddr);
ENTRYHI_SET_ASID(entryhi, pmap->asid);
tlb_invalidate(entryhi);
}
void unmap(pgd_t *pgd_now, uint32_t va)
{
uint32_t pgd_idx = PGD_INDEX(va);
uint32_t pte_idx = PTE_INDEX(va);
pte_t *pte = (pte_t *)(pgd_now[pgd_idx] & PAGE_MASK);
if (!pte) {
return;
}
// 转换到内核线性地址
pte = (pte_t *)(pa_to_ka(pte));
pte[pte_idx] = 0;
tlb_reload_page(va);
}
void map(pgd_t *pgd_now, uint32_t va, uint32_t pa, uint32_t flags)
{
uint32_t pgd_idx = PGD_INDEX(va);
uint32_t pte_idx = PTE_INDEX(va);
pte_t *pte = (pte_t *)(pgd_now[pgd_idx] & PAGE_MASK);
if (!pte) {
pte = (pte_t *)alloc_pages(1);
pgd_now[pgd_idx] = (uint32_t)pte | PAGE_PRESENT | PAGE_WRITE;
pte = (pte_t *)pa_to_ka(pte);
} else {
pte = (pte_t *)pa_to_ka(pte);
}
pte[pte_idx] = (pa & PAGE_MASK) | flags;
tlb_reload_page(va);
}
uint32_t get_mapping(pgd_t *pgd_now, uint32_t va, uint32_t *pa)
{
uint32_t pgd_idx = PGD_INDEX(va);
uint32_t pte_idx = PTE_INDEX(va);
pte_t *pte = (pte_t *)(pgd_now[pgd_idx] & PAGE_MASK);
if (!pte) {
return 0;
}
// 转换到内核线性地址
pte = (pte_t *)(pa_to_ka(pte));
// 如果地址有效而且指针不为NULL，则返回地址
if (pte[pte_idx] != 0 && pa) {
*pa = pte[pte_idx] & PAGE_MASK;
return 1;
}
return 0;
}
VOID
HalpReleaseReservedVirtualSpace(
PVOID VirtualAddress,
ULONG LengthInPages
)
/*++
Routine Description:
This function will release the virtual address range previously
allocated with HalpAssignReservedVirtualSpace and should be
called with a virtual address previously allocated by a call to
HalpAssignReservedVirtualSpace the number of pages to release.
Arguments:
VirtualAddress of a previously allocated page in the HAL reserved
space.
Length (in pages) to be released.
Return Value:
None.
--*/
{
PHARDWARE_PTE PPte;
//
// Sanity Checks
//
if ( (LengthInPages > MAX_LENGTH) ||
(!LengthInPages) ||
((ULONG)VirtualAddress < MIN_VA) ||
((ULONG)VirtualAddress > MAX_VA) ) {
KeBugCheck(HAL_INITIALIZATION_FAILED);
return;
}
if ( !HalpReservedPtes ) {
KeBugCheck(HAL_INITIALIZATION_FAILED);
return;
}
PPte = HalpReservedPtes + PTE_INDEX(VirtualAddress);
do {
if ( !PPte->Valid ) {
break;
}
PPte->Valid = FALSE;
PPte++;
} while ( --LengthInPages );
if ( LengthInPages ) {
KeBugCheck(HAL_INITIALIZATION_FAILED);
}
KeFlushCurrentTb();
return;
}
PVOID
HalpAssignReservedVirtualSpace(
ULONG BasePage,
ULONG LengthInPages
)
/*++
Routine Description:
This function will attempt to allocate a contiguous range of
virtual address to provide access to memory at the requested
physical address.
Arguments:
Physical page number for which a Virtual Address assignment is
needed.
Length (in pages) of the region to be mapped.
Return Value:
Virtual Address in the range HAL_BASE thru HAL_TOP + fff,
-or-
NULL if the assignment couldn't be made.
--*/
{
ULONG Length;
HARDWARE_PTE TempPte;
HARDWARE_PTE ZeroPte;
PHARDWARE_PTE PPte;
PHARDWARE_PTE StartingPte;
//
// Sanity Checks
//
if ( (LengthInPages > MAX_LENGTH) ||
(!LengthInPages) ||
(BasePage & ~PAGE_MASK) ) {
KeBugCheck(HAL_INITIALIZATION_FAILED);
return NULL;
}
if ( !HalpReservedPtes ) {
//
// Not initialized yet,... fix it.
//
HalpLocateReservedPtes();
}
PPte = HalpReservedPtes + PTE_INDEX(MIN_VA);
Length = LengthInPages;
while ( PPte <= (HalpReservedPtes + PTE_INDEX(MIN_VA)) || Length ) {
if ( PPte->Valid ) {
Length = LengthInPages;
} else {
Length--;
}
PPte++;
}
if ( Length ) {
return NULL;
}
//
// Found a range of pages. PPte is pointing to the entry
// beyond the end of the range.
//
StartingPte = PPte - LengthInPages;
PPte = StartingPte;
*(PULONG)&ZeroPte = 0;
TempPte = ZeroPte;
TempPte.Write = TRUE;
TempPte.CacheDisable = TRUE;
TempPte.MemoryCoherence = TRUE;
TempPte.GuardedStorage = TRUE;
TempPte.Dirty = 0x00; // PP bits KM read/write, UM no access.
TempPte.Valid = TRUE;
while ( LengthInPages-- ) {
//
// The following is done in a Temp so the actual write
// to the page table is done in a single write.
//
TempPte.PageFrameNumber = BasePage++;
*PPte++ = TempPte;
}
return (PVOID)(BASE_VA |
((ULONG)(StartingPte - HalpReservedPtes) << PAGE_SHIFT));
}