#define NDEBUG
#include <debug.h>
+#define PDE_BITS 10
+#define PTE_BITS 10
+
/* FUNCTIONS *****************************************************************/
ULONG_PTR
/* FIXME: Support this */
DPRINT("PAT support detected but not yet taken advantage of\n");
}
+
+ULONG_PTR
+NTAPI
+INIT_FUNCTION
+Ki386EnableTargetLargePage(IN ULONG_PTR Context)
+{
+ PLARGE_IDENTITY_MAP IdentityMap = (PLARGE_IDENTITY_MAP)Context;
+
+ /* Call helper function with the start address and temporary page table pointer */
+ Ki386EnableCurrentLargePage(IdentityMap->StartAddress, IdentityMap->Cr3);
+
+ return 0;
+}
+
+PVOID
+NTAPI
+Ki386AllocateContiguousMemory(PLARGE_IDENTITY_MAP IdentityMap,
+ ULONG PagesCount,
+ BOOLEAN InLower4Gb)
+{
+ PHYSICAL_ADDRESS AddressMask;
+ PVOID Result;
+ ULONG SizeInBytes = PagesCount * PAGE_SIZE;
+
+ /* Initialize acceptable address mask to any possible address */
+ AddressMask.LowPart = 0xFFFFFFFF;
+ AddressMask.HighPart = 0xFFFFFFFF;
+
+ /* Mark out higher 4Gb if caller asked so */
+ if (InLower4Gb) AddressMask.HighPart = 0;
+
+ /* Try to allocate the memory */
+ Result = MmAllocateContiguousMemory(SizeInBytes, AddressMask);
+ if (!Result) return NULL;
+
+ /* Zero it out */
+ RtlZeroMemory(Result, SizeInBytes);
+
+ /* Track allocated pages in the IdentityMap structure */
+ IdentityMap->PagesList[IdentityMap->PagesCount] = Result;
+ IdentityMap->PagesCount++;
+
+ return Result;
+}
+
+PHYSICAL_ADDRESS
+NTAPI
+Ki386BuildIdentityBuffer(PLARGE_IDENTITY_MAP IdentityMap,
+ PVOID StartPtr,
+ ULONG Length)
+{
+ // TODO: Check whether all pages are below 4GB boundary
+ return MmGetPhysicalAddress(StartPtr);
+}
+
+BOOLEAN
+NTAPI
+Ki386IdentityMapMakeValid(PLARGE_IDENTITY_MAP IdentityMap,
+ PHARDWARE_PTE Pde,
+ PHARDWARE_PTE *PageTable)
+{
+ ULONG NewPage;
+
+ if (Pde->Valid == 0)
+ {
+ /* Invalid, so allocate a new page for it */
+ NewPage = (ULONG)Ki386AllocateContiguousMemory(IdentityMap, 1, FALSE);
+ if (!NewPage) return FALSE;
+
+ /* Set PFN to its virtual address and mark it as valid */
+ Pde->PageFrameNumber = NewPage >> PAGE_SHIFT;
+ Pde->Valid = 1;
+
+ /* Pass page table address to the caller */
+ if (PageTable) *PageTable = (PHARDWARE_PTE)NewPage;
+ }
+ else
+ {
+ /* Valid entry, just pass the page table address to the caller */
+ if (PageTable)
+ *PageTable = (PHARDWARE_PTE)(Pde->PageFrameNumber << PAGE_SHIFT);
+ }
+
+ return TRUE;
+}
+
+BOOLEAN
+NTAPI
+Ki386MapAddress(PLARGE_IDENTITY_MAP IdentityMap,
+ ULONG_PTR VirtualPtr,
+ PHYSICAL_ADDRESS PhysicalPtr)
+{
+ PHARDWARE_PTE Pde, Pte;
+ PHARDWARE_PTE PageTable;
+
+ /* Allocate page directory on demand */
+ if (!IdentityMap->TopLevelDirectory)
+ {
+ IdentityMap->TopLevelDirectory = Ki386AllocateContiguousMemory(IdentityMap, 1, 1);
+ if (!IdentityMap->TopLevelDirectory) return FALSE;
+ }
+
+ /* Get PDE of VirtualPtr and make it writable and valid */
+ Pde = &IdentityMap->TopLevelDirectory[(VirtualPtr >> 22) & ((1 << PDE_BITS) - 1)];
+ if (!Ki386IdentityMapMakeValid(IdentityMap, Pde, &PageTable)) return FALSE;
+ Pde->Write = 1;
+
+ /* Get PTE of VirtualPtr, make it valid, and map PhysicalPtr there */
+ Pte = &PageTable[(VirtualPtr >> 12) & ((1 << PTE_BITS) - 1)];
+ Pte->Valid = 1;
+ Pte->PageFrameNumber = PhysicalPtr.QuadPart >> PAGE_SHIFT;
+
+ return TRUE;
+}
+
+VOID
+NTAPI
+Ki386ConvertPte(PHARDWARE_PTE Pte)
+{
+ PVOID VirtualPtr;
+ PHYSICAL_ADDRESS PhysicalPtr;
+
+ /* Get virtual and physical addresses */
+ VirtualPtr = (PVOID)(Pte->PageFrameNumber << PAGE_SHIFT);
+ PhysicalPtr = MmGetPhysicalAddress(VirtualPtr);
+
+ /* Map its physical address in the page table provided by the caller */
+ Pte->PageFrameNumber = PhysicalPtr.QuadPart >> PAGE_SHIFT;
+}
+
+BOOLEAN
+NTAPI
+Ki386CreateIdentityMap(PLARGE_IDENTITY_MAP IdentityMap, PVOID StartPtr, ULONG PagesCount)
+{
+ ULONG_PTR Ptr;
+ ULONG PteIndex;
+ PHYSICAL_ADDRESS IdentityPtr;
+
+ /* Zero out the IdentityMap contents */
+ RtlZeroMemory(IdentityMap, sizeof(LARGE_IDENTITY_MAP));
+
+ /* Get the pointer to the physical address and save it in the struct */
+ IdentityPtr = Ki386BuildIdentityBuffer(IdentityMap, StartPtr, PagesCount);
+ IdentityMap->StartAddress = IdentityPtr.LowPart;
+ if (IdentityMap->StartAddress == 0)
+ {
+ DPRINT1("Failed to get buffer for large pages identity mapping\n");
+ return FALSE;
+ }
+ DPRINT("IdentityMap->StartAddress %p\n", IdentityMap->StartAddress);
+
+ /* Map all pages */
+ for (Ptr = (ULONG_PTR)StartPtr;
+ Ptr < (ULONG_PTR)StartPtr + PagesCount * PAGE_SIZE;
+ Ptr += PAGE_SIZE, IdentityPtr.QuadPart += PAGE_SIZE)
+ {
+ /* Map virtual address */
+ if (!Ki386MapAddress(IdentityMap, Ptr, IdentityPtr)) return FALSE;
+
+ /* Map physical address */
+ if (!Ki386MapAddress(IdentityMap, IdentityPtr.LowPart, IdentityPtr)) return FALSE;
+ }
+
+ /* Convert all PTEs in the page directory from virtual to physical,
+ because Ki386IdentityMapMakeValid mapped only virtual addresses */
+ for (PteIndex = 0; PteIndex < (PAGE_SIZE / sizeof(HARDWARE_PTE)); PteIndex++)
+ {
+ if (IdentityMap->TopLevelDirectory[PteIndex].Valid != 0)
+ Ki386ConvertPte(&IdentityMap->TopLevelDirectory[PteIndex]);
+ }
+
+ /* Save the page directory address (allocated by Ki386MapAddress) */
+ IdentityMap->Cr3 = MmGetPhysicalAddress(IdentityMap->TopLevelDirectory).LowPart;
+
+ DPRINT("IdentityMap->Cr3 0x%x\n", IdentityMap->Cr3);
+
+ return TRUE;
+}
+
+VOID
+NTAPI
+Ki386FreeIdentityMap(PLARGE_IDENTITY_MAP IdentityMap)
+{
+ ULONG Page;
+
+ DPRINT("Freeing %d pages allocated for identity mapping\n", IdentityMap->PagesCount);
+
+ /* Free all allocated pages, if any */
+ for (Page = 0; Page < IdentityMap->PagesCount; Page++)
+ MmFreeContiguousMemory(IdentityMap->PagesList[Page]);
+}
projects / reactos.git / blobdiff