/**
* PROJECT: ExectOS
* COPYRIGHT: See COPYING.md in the top level directory
* FILE: xtldr/amd64/memory.c
* DESCRIPTION: EFI memory management for AMD64 target
* DEVELOPERS: Rafal Kupiec <belliash@codingworkshop.eu.org>
*/
#include <xtbl.h>
/**
* Builds the actual memory mapping page table and enables paging. This routine exits EFI boot services as well.
*
* @param MemoryMappings
* Supplies a pointer to linked list containing all memory mappings.
*
* @param VirtualAddress
* Supplies a pointer to the next valid, free and available virtual address.
*
* @param ImageProtocol
* A pointer to the EFI loaded image protocol with information about where in memory the loader code was placed.
*
* @param PtePointer
* Supplies a pointer to memory area containing a Page Table Entries (PTE).
*
* @return This routine returns a status code.
*
* @since XT 1.0
*/
XTCDECL
EFI_STATUS
BlEnablePaging(IN PLIST_ENTRY MemoryMappings,
IN PVOID VirtualAddress,
IN PEFI_LOADED_IMAGE_PROTOCOL ImageProtocol,
IN PVOID *PtePointer)
{
PLOADER_MEMORY_MAPPING Mapping;
EFI_PHYSICAL_ADDRESS Address;
PEFI_MEMORY_MAP MemoryMap;
PLIST_ENTRY ListEntry;
EFI_STATUS Status;
/* Allocate pages for PML4 */
Status = BlEfiMemoryAllocatePages(1, &Address);
if(Status != STATUS_EFI_SUCCESS)
{
/* Memory allocation failure */
return Status;
}
/* Assign and zero-fill memory used by page mappings */
*PtePointer = (PVOID)(UINT_PTR)Address;
RtlZeroMemory(*PtePointer, EFI_PAGE_SIZE);
/* Map XTLDR code */
Status = BlAddVirtualMemoryMapping(MemoryMappings, ImageProtocol->ImageBase, ImageProtocol->ImageBase,
EFI_SIZE_TO_PAGES(ImageProtocol->ImageSize), LoaderFirmwareTemporary);
if(Status != STATUS_EFI_SUCCESS)
{
/* Mapping the boot loader code failed */
return Status;
}
/* Add page mapping itself to memory mapping */
Status = BlAddVirtualMemoryMapping(MemoryMappings, NULL, *PtePointer, 1, LoaderMemoryData);
if(Status != STATUS_EFI_SUCCESS)
{
/* Mapping PML4 failed */
return Status;
}
/* Iterate through and map all the mappings*/
BlDbgPrint(L"Mapping and dumping EFI memory:\n");
ListEntry = MemoryMappings->Flink;
while(ListEntry != MemoryMappings)
{
/* Take mapping from the list */
Mapping = CONTAIN_RECORD(ListEntry, LOADER_MEMORY_MAPPING, ListEntry);
/* Check if virtual address is set */
if(Mapping->VirtualAddress)
{
/* Dump memory mapping */
BlDbgPrint(L" Type=%02lu, PhysicalBase=0x%016lx, VirtualBase=0x%016lx, Pages=%lu\n", Mapping->MemoryType,
Mapping->PhysicalAddress, Mapping->VirtualAddress, Mapping->NumberOfPages);
/* Map memory */
Status = BlMapVirtualMemory(MemoryMappings, (UINT_PTR)Mapping->VirtualAddress,
(UINT_PTR)Mapping->PhysicalAddress, Mapping->NumberOfPages, PtePointer);
if(Status != STATUS_EFI_SUCCESS)
{
/* Memory mapping failed */
return Status;
}
}
/* Take next element */
ListEntry = ListEntry->Flink;
}
/* Allocate and zero-fill buffer for EFI memory map */
BlEfiMemoryAllocatePool(sizeof(EFI_MEMORY_MAP), (PVOID*)&MemoryMap);
RtlZeroMemory(MemoryMap, sizeof(EFI_MEMORY_MAP));
/* Get EFI memory map and prepare for exiting boot services */
BlDbgPrint(L"Exiting EFI boot services\n");
Status = BlGetMemoryMap(MemoryMap);
if(Status != STATUS_EFI_SUCCESS)
{
/* Unable to get memory map */
return Status;
}
/* Exit EFI Boot Services */
Status = EfiSystemTable->BootServices->ExitBootServices(EfiImageHandle, MemoryMap->MapKey);
if(Status != STATUS_EFI_SUCCESS)
{
BlDbgPrint(L"Failed to exit boot services (Status code: %lx)\n", Status);
return STATUS_EFI_ABORTED;
}
/* Write PML4 to CR3 */
ArWriteControlRegister(3, (UINT_PTR)*PtePointer);
/* Return success */
return STATUS_EFI_SUCCESS;
}
/**
* This routine does the actual virtual memory mapping.
*
* @param MemoryMappings
* Supplies a pointer to linked list containing all memory mappings.
*
* @param VirtualAddress
* Supplies a virtual address of the mapping.
*
* @param PhysicalAddress
* Supplies a physical address of the mapping.
*
* @param NumberOfPages
* Supplies a number of the pages of the mapping.
*
* @param PaeExtension
* Specifies whether Physical Address Extension (PAE) is supported by the hardware. Not used on AMD64.
*
* @param PtePointer
* Supplies a pointer to an array of pointers to page table entries.
*
* @return This routine returns a status code.
*
* @since XT 1.0
*/
XTCDECL
EFI_STATUS
BlMapVirtualMemory(IN PLIST_ENTRY MemoryMappings,
IN UINT_PTR VirtualAddress,
IN UINT_PTR PhysicalAddress,
IN UINT NumberOfPages,
IN OUT PVOID *PtePointer)
{
PHARDWARE_PTE PageDirectoryPointTable, PageDirectory, PageTable;
UINT Pml4Index, PdpIndex, PdIndex, PtIndex;
EFI_PHYSICAL_ADDRESS Address;
UINT_PTR PageFrameNumber;
EFI_STATUS Status;
UINT64 Pointer;
/* Set the PFN */
PageFrameNumber = PhysicalAddress >> EFI_PAGE_SHIFT;
/* Do the recursive mapping */
while(NumberOfPages > 0)
{
/* Calculate indices from a virtual address */
Pml4Index = (VirtualAddress >> 39) & 0x1FF;
PdpIndex = (VirtualAddress >> 30) & 0x1FF;
PdIndex = (VirtualAddress >> 21) & 0x1FF;
PtIndex = (VirtualAddress >> 12) & 0x1FF;
/* Validate Page Map Level 4 (PML4) */
if(!((PHARDWARE_PTE)(*PtePointer))[Pml4Index].Valid)
{
/* Allocate pages for the PDPT */
Status = BlEfiMemoryAllocatePages(1, &Address);
if (Status != STATUS_EFI_SUCCESS) {
/* Memory allocation failure */
return Status;
}
/* Add new memory mapping */
Status = BlAddVirtualMemoryMapping(MemoryMappings, NULL, (PVOID)(UINT_PTR)Address, 1, LoaderMemoryData);
if(Status != STATUS_EFI_SUCCESS) {
/* Memory mapping failed */
return Status;
}
/* Fill allocated memory with zeros */
RtlZeroMemory((PVOID)(UINT_PTR)Address, EFI_PAGE_SIZE);
/* Set paging entry settings */
((PHARDWARE_PTE)(*PtePointer))[Pml4Index].PageFrameNumber = Address / EFI_PAGE_SIZE;
((PHARDWARE_PTE)(*PtePointer))[Pml4Index].Valid = 1;
((PHARDWARE_PTE)(*PtePointer))[Pml4Index].Write = 1;
PageDirectoryPointTable = (PHARDWARE_PTE)(UINT_PTR)Address;
}
else
{
/* Find Page Directory Point Table (PDPT) */
Pointer = ((PHARDWARE_PTE)(*PtePointer))[Pml4Index].PageFrameNumber;
Pointer <<= EFI_PAGE_SHIFT;
PageDirectoryPointTable = (PHARDWARE_PTE)(UINT_PTR)Pointer;
}
/* Validate Page Directory Point Table (PDPT)*/
if(!PageDirectoryPointTable[PdpIndex].Valid)
{
/* Allocate pages for the PD */
Status = BlEfiMemoryAllocatePages(1, &Address);
if (Status != STATUS_EFI_SUCCESS) {
/* Memory allocation failure */
return Status;
}
/* Add new memory mapping */
Status = BlAddVirtualMemoryMapping(MemoryMappings, NULL, (PVOID)(UINT_PTR)Address, 1, LoaderMemoryData);
if (Status != STATUS_EFI_SUCCESS) {
/* Memory mapping failed */
return Status;
}
/* Fill allocated memory with zeros */
RtlZeroMemory((PVOID)(UINT_PTR)Address, EFI_PAGE_SIZE);
/* Set paging entry settings */
PageDirectoryPointTable[PdpIndex].PageFrameNumber = Address / EFI_PAGE_SIZE;
PageDirectoryPointTable[PdpIndex].Valid = 1;
PageDirectoryPointTable[PdpIndex].Write = 1;
PageDirectory = (PHARDWARE_PTE)(UINT_PTR)Address;
}
else
{
/* Find Page Directory (PD) */
Pointer = PageDirectoryPointTable[PdpIndex].PageFrameNumber;
Pointer <<= EFI_PAGE_SHIFT;
PageDirectory = (PHARDWARE_PTE)(UINT_PTR)Pointer;
}
/* Validate Page Directory (PD)*/
if(!PageDirectory[PdIndex].Valid)
{
/* Allocate pages for the PT */
Status = BlEfiMemoryAllocatePages(1, &Address);
if (Status != STATUS_EFI_SUCCESS) {
/* Memory allocation failure */
return Status;
}
/* Add new memory mapping */
Status = BlAddVirtualMemoryMapping(MemoryMappings, NULL, (PVOID)(UINT_PTR)Address, 1, LoaderMemoryData);
if (Status != STATUS_EFI_SUCCESS) {
/* Memory mapping failed */
return Status;
}
/* Fill allocated memory with zeros */
RtlZeroMemory((PVOID)(UINT_PTR)Address, EFI_PAGE_SIZE);
/* Set paging entry settings */
PageDirectory[PdIndex].PageFrameNumber = Address / EFI_PAGE_SIZE;
PageDirectory[PdIndex].Valid = 1;
PageDirectory[PdIndex].Write = 1;
PageTable = (PHARDWARE_PTE)(UINT_PTR)Address;
}
else
{
/* Find Page Table (PT) */
Pointer = PageDirectory[PdIndex].PageFrameNumber;
Pointer <<= EFI_PAGE_SHIFT;
PageTable = (PHARDWARE_PTE)(UINT_PTR)Pointer;
}
/* Set paging entry settings */
PageTable[PtIndex].PageFrameNumber = PageFrameNumber;
PageTable[PtIndex].Valid = 1;
PageTable[PtIndex].Write = 1;
/* Take next virtual address and PFN */
VirtualAddress += EFI_PAGE_SIZE;
PageFrameNumber++;
/* Decrease number of pages left */
NumberOfPages--;
}
/* Return success */
return STATUS_EFI_SUCCESS;
}