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Overhaul kernel memory layout initialization and pool sizing
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This commit is contained in:
Aiken Harris
2026-01-30 14:47:13 +01:00
parent 726fd84241
commit 6a7bc64ac7
3 changed files with 774 additions and 86 deletions
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459
xtoskrnl/mm/i686/mmgr.cc
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@@ -9,6 +9,283 @@
#include <xtos.hh>
/**
* Calculates the maximum possible size of the non-paged pool.
*
* @param PoolSize
* A pointer to a variable that will receive the number of pages available for the non-paged pool.
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Manager::ComputeMaximumNonPagedPoolSize(OUT PPFN_NUMBER PoolSize)
{
ULONG_PTR MaximumNonPagedPoolSize;
ULONGLONG PhysicalPages;
/* Get number of physical pages */
PhysicalPages = MM::Pfn::GetNumberOfPhysicalPages();
/* Start with 1MiB and reserve space for PFN database */
MaximumNonPagedPoolSize = 1048576;
/* Check if system has at least 512MiB of physical memory */
if(PhysicalPages >= 126976)
{
/* Add 200KiB for each MiB above 4MiB */
MaximumNonPagedPoolSize += ((PhysicalPages - 1024)/256) * 204800;
/* Check if non-paged pool has at least 128MiB */
if(MaximumNonPagedPoolSize < 134217728)
{
/* Expand non-paged pool size to 128MiB */
MaximumNonPagedPoolSize = 134217728;
}
}
else
{
/* Add 400KiB for each MiB above 4MiB */
MaximumNonPagedPoolSize += ((PhysicalPages - 1024)/256) * 409600;
}
/* Check if non-paged pool does not exceed 256MiB */
if(MaximumNonPagedPoolSize > 268435456)
{
/* Limit non-paged pool size to 256MiB */
MaximumNonPagedPoolSize = 268435456;
}
/* Return maximum non-paged pool size in pages */
*PoolSize = SIZE_TO_PAGES(MaximumNonPagedPoolSize);
}
/**
* Calculates the size of the non-paged pool.
*
* @param PoolSize
* A pointer to a variable that will receive the number of pages available for the non-paged pool.
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Manager::ComputeNonPagedPoolSize(OUT PPFN_NUMBER PoolSize)
{
ULONG_PTR NonPagedPoolSize;
ULONGLONG PhysicalPages;
/* Get number of physical pages */
PhysicalPages = MM::Pfn::GetNumberOfPhysicalPages();
/* Verify if system has less than 256MiB of physical memory */
if(PhysicalPages <= 65536)
{
/* Reduce initial non-paged pool size to 2MiB to save memory */
NonPagedPoolSize = 2097152;
}
else
{
/* Start with 256KiB and add 32KiB for each MiB above 4MiB */
NonPagedPoolSize = 262144 + (((PhysicalPages - 1024) / 256) * 32768);
if(NonPagedPoolSize > 134217728)
{
/* Limit non-paged pool size to 128MiB */
NonPagedPoolSize = 134217728;
}
}
/* Return non-paged pool size in pages, aligned down to page size boundary */
*PoolSize = SIZE_TO_PAGES(ROUND_DOWN(NonPagedPoolSize, MM_PAGE_SIZE));
}
/**
* Calculates the size of the paged pool.
*
* @param PoolSize
* A pointer to a variable that will receive the number of pages available for the paged pool.
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Manager::ComputePagedPoolSize(OUT PPFN_NUMBER PoolSize)
{
ULONG_PTR PagedPoolSize, PteCount;
ULONG PtesPerPage;
/* Start with maximum non-paged pool size */
ComputeMaximumNonPagedPoolSize(&PagedPoolSize);
PagedPoolSize *= MM_PAGE_SIZE;
/* Check XPA status */
if(MM::Paging::GetXpaStatus())
{
/* Four times the non-paged pool size on PAE-enabled systems */
PagedPoolSize *= 4;
}
else
{
/* Double the non-paged pool size on PAE-disabled systems */
PagedPoolSize *= 2;
}
/* Check if paged pool does not overlap non-paged pool */
if(PagedPoolSize > (ULONG_PTR)MemoryLayout.NonPagedSystemPoolStart - (ULONG_PTR)MemoryLayout.PagedPoolStart)
{
/* Limit paged pool size to maximum possible */
PagedPoolSize = (ULONG_PTR)MemoryLayout.NonPagedSystemPoolStart - (ULONG_PTR)MemoryLayout.PagedPoolStart;
}
/* Ensure that paged pool size is at least 32MiB */
if(PagedPoolSize < 33554432)
{
/* Increase paged pool size to at least 32MiB */
PagedPoolSize = 33554432;
}
/* Get the number of PTEs per page and calculate size of paged pool */
PtesPerPage = MM::Pte::GetPtesPerPage();
PteCount = ((SIZE_TO_PAGES(PagedPoolSize) + (PtesPerPage - 1)) / PtesPerPage);
/* Return paged pool size */
*PoolSize = (PFN_NUMBER)(PteCount * PtesPerPage);
}
/**
* Calculates the size of the session space.
*
* @param SpaceSize
* A pointer to a variable that will receive the number of pages available by the session space.
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Manager::ComputeSessionSpaceSize(OUT PPFN_NUMBER SpaceSize)
{
PFN_NUMBER SessionSpaceSize;
/* Session Pool, Session View, Session Image, Session Working Set and System View takes 108MiB */
SessionSpaceSize = 113246208;
/* Return number of pages used by the session space */
*SpaceSize = SessionSpaceSize / MM_PAGE_SIZE;
}
/**
* Calculates the size of the system PTEs.
*
* @param PteSize
* A pointer to a variable that will receive the number of system PTEs.
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Manager::ComputeSystemPteSize(OUT PPFN_NUMBER PteSize)
{
PFN_NUMBER SystemPteSize;
/* Check if system has less than 19MiB of physical memory */
if(MM::Pfn::GetNumberOfPhysicalPages() < 4864)
{
/* Set minimal system PTE size */
SystemPteSize = 7000;
}
else
{
/* Use standard system PTE size */
SystemPteSize = 11000;
/* Check if system has more than 32MiB of physical memory */
if(MM::Pfn::GetNumberOfPhysicalPages() > 8192)
{
/* Double system PTE size */
SystemPteSize *= 2;
/* Check if system has more than 256MiB of physical memory */
if(MM::Pfn::GetNumberOfPhysicalPages() > 65536)
{
/* Double system PTE size */
SystemPteSize *= 2;
}
}
}
/* Return system PTE size */
*PteSize = SystemPteSize;
}
/**
* Dumps the kernel's memory layout.
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Manager::DumpMemoryLayout(VOID)
{
/* Dump memory layout */
DebugPrint(L"System with %zu MiB of installed memory:\n"
L"User Space: %.8P - %.8P\n"
L"Loader Mappings: %.8P - %.8P\n"
L"PFN Database: %.8P - %.8P\n"
L"Non-Paged Pool: %.8P - %.8P\n"
L"Session Space: %.8P - %.8P\n"
L"PTE Space: %.8P - %.8P\n"
L"Hyper Space: %.8P - %.8P\n"
L"System Working Set: %.8P - %.8P\n"
L"System Cache: %.8P - %.8P\n"
L"Paged Pool: %.8P - %.8P\n"
L"Non-Paged System Pool: %.8P - %.8P\n"
L"Non-Paged Expansion Pool: %.8P - %.8P\n"
L"Shared System Page: %.8P - %.8P\n"
L"Hardware Pool: %.8P - %.8P\n",
GetInstalledMemorySize(),
MemoryLayout.UserSpaceStart,
MemoryLayout.UserSpaceEnd,
MemoryLayout.LoaderMappingsStart,
MemoryLayout.LoaderMappingsEnd,
MemoryLayout.PfnDatabase,
(PVOID)((ULONG_PTR)MemoryLayout.PfnDatabase + (ULONG_PTR)MemoryLayout.PfnDatabaseSize * MM_PAGE_SIZE),
MemoryLayout.NonPagedPoolStart,
MemoryLayout.NonPagedPoolEnd,
MemoryLayout.SessionSpaceStart,
MemoryLayout.SessionSpaceEnd,
MemoryLayout.PteSpaceStart,
MemoryLayout.PteSpaceEnd,
MemoryLayout.HyperSpaceStart,
MemoryLayout.HyperSpaceEnd,
MemoryLayout.SystemWorkingSetStart,
MemoryLayout.SystemWorkingSetEnd,
MemoryLayout.SystemCacheStart,
MemoryLayout.SystemCacheEnd,
MemoryLayout.PagedPoolStart,
MemoryLayout.PagedPoolEnd,
MemoryLayout.NonPagedSystemPoolStart,
MemoryLayout.NonPagedSystemPoolEnd,
MemoryLayout.NonPagedExpansionPoolStart,
MemoryLayout.NonPagedExpansionPoolEnd,
MemoryLayout.SharedSystemPageStart,
MemoryLayout.SharedSystemPageEnd,
MemoryLayout.HardwarePoolStart,
MemoryLayout.HardwarePoolEnd);
}
/**
* Initializes the kernel's virtual memory layout.
*
@@ -20,69 +297,153 @@ XTAPI
VOID
MM::Manager::InitializeMemoryLayout(VOID)
{
ULONG_PTR PagedPoolSize, PteCount;
PFN_NUMBER PhysicalPages;
ULONG PtesPerPage;
/* Define the number of system PTEs */
NumberOfSystemPtes = MM_DEFAULT_NUMBER_SYSTEM_PTES;
/* Retrieve the number of physical pages */
PhysicalPages = MM::Pfn::GetNumberOfPhysicalPages();
/* Verify the number of physical pages */
if(PhysicalPages < 8192)
{
/* Less than 32MiB of physical memory (8192 pages), use the minimum number of system PTEs */
NumberOfSystemPtes = MM_MINIMUM_NUMBER_SYSTEM_PTES;
}
else if(PhysicalPages > 32768)
{
/* More than 128MiB of physical memory (32768 pages), use the maximum number of system PTEs */
NumberOfSystemPtes = MM_MAXIMUM_NUMBER_SYSTEM_PTES;
}
/* Calculate size of paged pool */
PtesPerPage = MM::Pte::GetPtesPerPage();
PteCount = (SIZE_TO_PAGES(33554432) + (PtesPerPage - 1)) / PtesPerPage;
PagedPoolSize = PteCount * PtesPerPage * MM_PAGE_SIZE;
/* Retrieve the PFN database size */
MM::Pfn::ComputePfnDatabaseSize(&MemoryLayout.PfnDatabaseSize);
PFN_NUMBER MaximumNonPagedPoolSize;
ULONG_PTR PfnDatabaseEnd;
/* Check if 3-level paging (PAE) is enabled */
if(MM::Paging::GetXpaStatus())
{
/* Configure memory layout for 3-level paging, using 36bit address space and providing a 64 GB address space */
MemoryLayout.PfnDatabase = (PMMPFN)0xB0000000;
/* Set PML3 base address */
MemoryLayout.SelfMapAddress = (PVOID)MM_PTE_BASE;
/* Define the non-paged and paged pool regions */
MemoryLayout.NonPagedPoolStart = (PVOID)((ULONG_PTR)MemoryLayout.PfnDatabase + MemoryLayout.PfnDatabaseSize * MM_PAGE_SIZE);
MemoryLayout.NonPagedPoolEnd = (PVOID)0xEEFFFFFF;
MemoryLayout.PagedPoolStart = (PVOID)0xE2000000;
MemoryLayout.PagedPoolEnd = (PVOID)(((ULONG_PTR)MemoryLayout.PagedPoolStart + PagedPoolSize) - 1);
/* Define hyperspace, system PTE space, and the user space limit */
/* Define memory layout for 3-level paging */
MemoryLayout.NonCanonicalStart = (PVOID)0x00000000;
MemoryLayout.NonCanonicalEnd = (PVOID)0x00000000;
MemoryLayout.ReservedSystemPoolStart = (PVOID)0x00000000;
MemoryLayout.ReservedSystemPoolEnd = (PVOID)0x00000000;
MemoryLayout.UserSpaceStart = (PVOID)0x00010000;
MemoryLayout.UserSpaceEnd = (PVOID)0x7FFEFFFF;
MemoryLayout.LoaderMappingsStart = (PVOID)0x80000000;
MemoryLayout.LoaderMappingsEnd = (PVOID)0x90000000;
MemoryLayout.NonPagedPoolStart = (PVOID)0x90000000;
MemoryLayout.NonPagedPoolEnd = (PVOID)0xB0000000;
MemoryLayout.SessionSpaceStart = (PVOID)0xB0000000;
MemoryLayout.SessionSpaceEnd = (PVOID)0xC0000000;
MemoryLayout.PteSpaceStart = (PVOID)0xC0000000;
MemoryLayout.PteSpaceEnd = (PVOID)0xC07FFFFF;
MemoryLayout.HyperSpaceStart = (PVOID)0xC0800000;
MemoryLayout.HyperSpaceEnd = (PVOID)0xC0BFFFFF;
MemoryLayout.UserSpaceEnd = (PVOID)0x7FFEFFFF;
MemoryLayout.SystemWorkingSetStart = (PVOID)0xC0C00000;
MemoryLayout.SystemWorkingSetEnd = (PVOID)0xC0FFFFFF;
MemoryLayout.SystemCacheStart = (PVOID)0xC1000000;
MemoryLayout.SystemCacheEnd = (PVOID)0xE0FFFFFF;
MemoryLayout.PagedPoolStart = (PVOID)0xE1000000;
MemoryLayout.PagedPoolEnd = (PVOID)0xECC00000;
MemoryLayout.NonPagedSystemPoolStart = (PVOID)0xECC00000;
MemoryLayout.NonPagedSystemPoolEnd = (PVOID)0xF7BE0000;
MemoryLayout.NonPagedExpansionPoolStart = (PVOID)0xF7BE0000;
MemoryLayout.NonPagedExpansionPoolEnd = (PVOID)0xFFBFF000;
MemoryLayout.SharedSystemPageStart = (PVOID)0xFFBFF000;
MemoryLayout.SharedSystemPageEnd = (PVOID)0xFFC00000;
MemoryLayout.HardwarePoolStart = (PVOID)0xFFC00000;
MemoryLayout.HardwarePoolEnd = (PVOID)0xFFFFFFFF;
}
else
{
/* Configure memory layout for 2-level paging, using 32bit address space and providing a 4 GB address space */
MemoryLayout.PfnDatabase = (PMMPFN)0xB0000000;
/* Set PML2 base address */
MemoryLayout.SelfMapAddress = (PVOID)MM_PTE_BASE;
/* Define the non-paged and paged pool regions */
MemoryLayout.NonPagedPoolStart = (PVOID)((ULONG_PTR)MemoryLayout.PfnDatabase + MemoryLayout.PfnDatabaseSize * MM_PAGE_SIZE);
MemoryLayout.NonPagedPoolEnd = (PVOID)0xFFBE0000;
MemoryLayout.PagedPoolStart = (PVOID)0xE1000000;
MemoryLayout.PagedPoolEnd = (PVOID)(((ULONG_PTR)MemoryLayout.PagedPoolStart + PagedPoolSize) - 1);
/* Define hyperspace, system PTE space, and the user space limit */
/* Define memory layout for 2-level paging */
MemoryLayout.NonCanonicalStart = (PVOID)0x00000000;
MemoryLayout.NonCanonicalEnd = (PVOID)0x00000000;
MemoryLayout.ReservedSystemPoolStart = (PVOID)0x00000000;
MemoryLayout.ReservedSystemPoolEnd = (PVOID)0x00000000;
MemoryLayout.UserSpaceStart = (PVOID)0x00010000;
MemoryLayout.UserSpaceEnd = (PVOID)0x7FFEFFFF;
MemoryLayout.LoaderMappingsStart = (PVOID)0x80000000;
MemoryLayout.LoaderMappingsEnd = (PVOID)0x90000000;
MemoryLayout.NonPagedPoolStart = (PVOID)0x90000000;
MemoryLayout.NonPagedPoolEnd = (PVOID)0xB0000000;
MemoryLayout.SessionSpaceStart = (PVOID)0xB0000000;
MemoryLayout.SessionSpaceEnd = (PVOID)0xC0000000;
MemoryLayout.PteSpaceStart = (PVOID)0xC0000000;
MemoryLayout.PteSpaceEnd = (PVOID)0xC03FFFFF;
MemoryLayout.HyperSpaceStart = (PVOID)0xC0400000;
MemoryLayout.HyperSpaceEnd = (PVOID)0xC07FFFFF;
MemoryLayout.UserSpaceEnd = (PVOID)0x7FFEFFFF;
MemoryLayout.SystemWorkingSetStart = (PVOID)0xC0C00000;
MemoryLayout.SystemWorkingSetEnd = (PVOID)0xC0FFFFFF;
MemoryLayout.SystemCacheStart = (PVOID)0xC1000000;
MemoryLayout.SystemCacheEnd = (PVOID)0xE0FFFFFF;
MemoryLayout.PagedPoolStart = (PVOID)0xE1000000;
MemoryLayout.PagedPoolEnd = (PVOID)0xECC00000;
MemoryLayout.NonPagedSystemPoolStart = (PVOID)0xECC00000;
MemoryLayout.NonPagedSystemPoolEnd = (PVOID)0xF7BE0000;
MemoryLayout.NonPagedExpansionPoolStart = (PVOID)0xF7BE0000;
MemoryLayout.NonPagedExpansionPoolEnd = (PVOID)0xFFBFF000;
MemoryLayout.SharedSystemPageStart = (PVOID)0xFFBFF000;
MemoryLayout.SharedSystemPageEnd = (PVOID)0xFFC00000;
MemoryLayout.HardwarePoolStart = (PVOID)0xFFC00000;
MemoryLayout.HardwarePoolEnd = (PVOID)0xFFFFFFFF;
}
/* Compute allocation size for the PFN database */
MM::Pfn::ComputePfnDatabaseSize(&MemoryLayout.PfnDatabaseSize);
/* Compute boot image size */
ComputeBootImageSize(&MemoryLayout.LoaderMappingsSize);
/* Compute session space size */
ComputeSessionSpaceSize(&MemoryLayout.SessionSpaceSize);
/* Update loader mappings space end address */
MemoryLayout.LoaderMappingsEnd = (PVOID)((ULONG_PTR)MemoryLayout.LoaderMappingsStart +
MemoryLayout.LoaderMappingsSize * MM_PAGE_SIZE);
/* Update session space start address */
MemoryLayout.SessionSpaceStart = (PVOID)((ULONGLONG)MemoryLayout.SessionSpaceEnd -
MemoryLayout.SessionSpaceSize * MM_PAGE_SIZE);
/* Compute system PTE size */
ComputeSystemPteSize(&NumberOfSystemPtes);
/* Compute non-paged pool size */
ComputeNonPagedPoolSize(&MemoryLayout.NonPagedPoolSize);
ComputeMaximumNonPagedPoolSize(&MaximumNonPagedPoolSize);
/* Compute paged pool size */
ComputePagedPoolSize(&MemoryLayout.PagedPoolSize);
/* Insert the PFN database right after the loader mappings */
MemoryLayout.PfnDatabase = (PMMPFN)MemoryLayout.LoaderMappingsEnd;
/* Compute the PFN database page-aligned end address */
PfnDatabaseEnd = (ULONG_PTR)MemoryLayout.PfnDatabase + (MemoryLayout.PfnDatabaseSize * MM_PAGE_SIZE);
PfnDatabaseEnd = ROUND_UP(PfnDatabaseEnd, MM_PAGE_SIZE);
/* Check in non-paged pool fits before session space */
if(MemoryLayout.NonPagedPoolSize * MM_PAGE_SIZE <= ((ULONG_PTR)MemoryLayout.SessionSpaceStart - PfnDatabaseEnd))
{
/* Set non-paged pool start and end addresses */
MemoryLayout.NonPagedPoolStart = (PVOID)PfnDatabaseEnd;
MemoryLayout.NonPagedPoolEnd = (PVOID)(PfnDatabaseEnd + MemoryLayout.NonPagedPoolSize * MM_PAGE_SIZE);
/* Check if non-paged expansion pool overflows */
if((ULONG_PTR)MemoryLayout.NonPagedExpansionPoolStart + MaximumNonPagedPoolSize *
MM_PAGE_SIZE >= (ULONG_PTR)MemoryLayout.NonPagedExpansionPoolStart)
{
/* Check if non-paged expansion pool fits */
if((ULONG_PTR)MemoryLayout.NonPagedExpansionPoolStart + MaximumNonPagedPoolSize *
MM_PAGE_SIZE <= (ULONG_PTR)MemoryLayout.NonPagedExpansionPoolEnd)
{
/* Set non-paged expansion pool end address */
MemoryLayout.NonPagedExpansionPoolEnd = (PVOID)((ULONG_PTR)MemoryLayout.NonPagedExpansionPoolStart +
MaximumNonPagedPoolSize * MM_PAGE_SIZE);
}
}
/* Compute non-paged expansion pool size */
MemoryLayout.NonPagedExpansionPoolSize = ((ULONG_PTR)MemoryLayout.NonPagedExpansionPoolEnd -
(ULONG_PTR)MemoryLayout.NonPagedExpansionPoolStart) / MM_PAGE_SIZE;
}
else
{
/* Unfortunally non-paged pool does not fit before session space. What can we do? */
}
/* Update paged pool end address */
MemoryLayout.PagedPoolEnd = (PVOID)(((ULONG_PTR)MemoryLayout.PagedPoolStart +
MemoryLayout.PagedPoolSize * MM_PAGE_SIZE) - 1);
/* Dump memory layout */
DumpMemoryLayout();
}