forked from xt-sys/exectos
120 lines
3.1 KiB
C++
120 lines
3.1 KiB
C++
/**
|
|
* PROJECT: ExectOS
|
|
* COPYRIGHT: See COPYING.md in the top level directory
|
|
* FILE: xtoskrnl/mm/pte.cc
|
|
* DESCRIPTION: Page table entry (PTE) support
|
|
* DEVELOPERS: Aiken Harris <harraiken91@gmail.com>
|
|
*/
|
|
|
|
#include <xtos.hh>
|
|
|
|
|
|
/**
|
|
* Calculates the number of Page Table Entries (PTEs) that fit within a single page.
|
|
*
|
|
* @return This routine returns the number of PTEs per page.
|
|
*
|
|
* @since XT 1.0
|
|
*/
|
|
XTAPI
|
|
ULONG
|
|
MM::Pte::GetPtesPerPage(VOID)
|
|
{
|
|
/* Calculate and return the number of PTEs per page */
|
|
return MM_PAGE_SIZE / MM::Paging::GetPteSize();
|
|
}
|
|
|
|
/**
|
|
* Maps a range of virtual addresses at the PDE (Page Directory Entry) level.
|
|
*
|
|
* @param StartAddress
|
|
* The beginning of the virtual address range to map.
|
|
*
|
|
* @param EndAddress
|
|
* The end of the virtual address range to map.
|
|
*
|
|
* @param TemplatePde
|
|
* A template PDE to use for creating new entries.
|
|
*
|
|
* @return This routine does not return any value.
|
|
*
|
|
* @since XT 1.0
|
|
*/
|
|
XTAPI
|
|
VOID
|
|
MM::Pte::MapPDE(PVOID StartAddress,
|
|
PVOID EndAddress,
|
|
PMMPDE TemplatePde)
|
|
{
|
|
PMMPDE EndSpace, PointerPde;
|
|
|
|
/* Get PDE addresses */
|
|
PointerPde = MM::Paging::GetPdeAddress(StartAddress);
|
|
EndSpace = MM::Paging::GetPdeAddress(EndAddress);
|
|
|
|
/* Iterate over all PDEs */
|
|
while(PointerPde <= EndSpace)
|
|
{
|
|
/* Check if PDE is already mapped */
|
|
if(!MM::Paging::PteValid(PointerPde))
|
|
{
|
|
/* Map PDE */
|
|
MM::Paging::SetPte(TemplatePde, MM::Pfn::AllocateBootstrapPages(1), 0);
|
|
*PointerPde = *TemplatePde;
|
|
|
|
/* Clear the page table */
|
|
RtlZeroMemory(MM::Paging::GetPteVirtualAddress(PointerPde), MM_PAGE_SIZE);
|
|
}
|
|
|
|
/* Get next table entry */
|
|
PointerPde = MM::Paging::GetNextPte(PointerPde);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Maps a range of virtual addresses at the PTE (Page Table Entry) level.
|
|
*
|
|
* @param StartAddress
|
|
* The beginning of the virtual address range to map.
|
|
*
|
|
* @param EndAddress
|
|
* The end of the virtual address range to map.
|
|
*
|
|
* @param TemplatePte
|
|
* A template PTE to use for creating new entries.
|
|
*
|
|
* @return This routine does not return any value.
|
|
*
|
|
* @since XT 1.0
|
|
*/
|
|
XTAPI
|
|
VOID
|
|
MM::Pte::MapPTE(PVOID StartAddress,
|
|
PVOID EndAddress,
|
|
PMMPTE TemplatePte)
|
|
{
|
|
PMMPTE EndSpace, PointerPte;
|
|
|
|
/* Get PTE addresses */
|
|
PointerPte = MM::Paging::GetPteAddress(StartAddress);
|
|
EndSpace = MM::Paging::GetPteAddress(EndAddress);
|
|
|
|
/* Iterate over all PTEs */
|
|
while(PointerPte <= EndSpace)
|
|
{
|
|
/* Check if PTE is already mapped */
|
|
if(!MM::Paging::PteValid(PointerPte))
|
|
{
|
|
/* Map PTE */
|
|
MM::Paging::SetPte(TemplatePte, MM::Pfn::AllocateBootstrapPages(1), 0);
|
|
*PointerPte = *TemplatePte;
|
|
|
|
/* Clear the page table */
|
|
RtlZeroMemory(MM::Paging::GetPteVirtualAddress(PointerPte), MM_PAGE_SIZE);
|
|
}
|
|
|
|
/* Get next table entry */
|
|
PointerPte = MM::Paging::GetNextPte(PointerPte);
|
|
}
|
|
}
|