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Make memory descriptor processing architecture-dependent
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This commit is contained in:
Aiken Harris
2026-01-05 23:39:42 +01:00
parent bd1a3605d2
commit 9027632c4f
3 changed files with 168 additions and 84 deletions
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84
xtoskrnl/mm/amd64/pfn.cc
View File

@@ -167,6 +167,90 @@ MM::Pfn::InitializePageTablePfns(VOID)
}
}
/**
* Processes a memory descriptor and initializes the corresponding PFN database entries
*
* @param BasePage
* The starting physical page number of the memory run
*
* @param PageCount
* The number of pages in the memory run
*
* @param MemoryType
* The type of memory as reported by the bootloader (e.g., free, ROM, in-use)
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Pfn::ProcessMemoryDescriptor(IN PFN_NUMBER BasePage,
IN PFN_NUMBER PageCount,
IN LOADER_MEMORY_TYPE MemoryType)
{
PFN_NUMBER CurrentPage, PageNumber;
PMMPFN Pfn;
/* Check if the memory descriptor describes a free memory region */
if(MM::Manager::VerifyMemoryTypeFree(MemoryType))
{
/* Iterate over each page in this free memory run */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current page and set its initial cache attribute */
CurrentPage = BasePage + PageNumber;
Pfn = GetPfnEntry(CurrentPage);
Pfn->u3.e1.CacheAttribute = PfnNonCached;
/* Add the page to the free list to make it available for allocation */
LinkFreePage(CurrentPage);
}
}
else
{
/* Handle all other (non-free) memory types */
switch(MemoryType)
{
case LoaderBad:
/* This memory is marked as bad and should not be used, add it to the bad pages list */
LinkPage(&BadPagesList, BasePage);
break;
case LoaderXIPRom:
/* This memory range contains Read-Only Memory (ROM) */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current ROM page */
Pfn = GetPfnEntry(BasePage + PageNumber);
/* Initialize the PFN entry to represent a ROM page */
Pfn->PteAddress = 0;
Pfn->u1.Flink = 0;
Pfn->u2.ShareCount = 0;
Pfn->u3.e1.CacheAttribute = PfnNonCached;
Pfn->u3.e1.PageLocation = 0;
Pfn->u3.e1.PrototypePte = 1;
Pfn->u3.e1.Rom = 1;
Pfn->u3.e2.ReferenceCount = 0;
Pfn->u4.InPageError = 0;
Pfn->u4.PteFrame = 0;
}
break;
default:
/* All other types are considered in-use (ie, by the kernel, ACPI, etc) */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current in-use page */
Pfn = GetPfnEntry(BasePage + PageNumber);
/* Mark the PFN as active and valid to prevent it from being allocated */
Pfn->u3.e1.PageLocation = ActiveAndValid;
}
break;
}
}
}
/**
* Recursively scans a page table to initialize PFN database entries for active pages.
*

84
xtoskrnl/mm/i686/pfn.cc
View File

@@ -155,6 +155,90 @@ MM::Pfn::InitializePageTablePfns(VOID)
}
}
/**
* Processes a memory descriptor and initializes the corresponding PFN database entries
*
* @param BasePage
* The starting physical page number of the memory run
*
* @param PageCount
* The number of pages in the memory run
*
* @param MemoryType
* The type of memory as reported by the bootloader (e.g., free, ROM, in-use)
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Pfn::ProcessMemoryDescriptor(IN PFN_NUMBER BasePage,
IN PFN_NUMBER PageCount,
IN LOADER_MEMORY_TYPE MemoryType)
{
PFN_NUMBER CurrentPage, PageNumber;
PMMPFN Pfn;
/* Check if the memory descriptor describes a free memory region */
if(MM::Manager::VerifyMemoryTypeFree(MemoryType))
{
/* Iterate over each page in this free memory run */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current page and set its initial cache attribute */
CurrentPage = BasePage + PageNumber;
Pfn = GetPfnEntry(CurrentPage);
Pfn->u3.e1.CacheAttribute = PfnNonCached;
/* Add the page to the free list to make it available for allocation */
LinkFreePage(CurrentPage);
}
}
else
{
/* Handle all other (non-free) memory types */
switch(MemoryType)
{
case LoaderBad:
/* This memory is marked as bad and should not be used, add it to the bad pages list */
LinkPage(&BadPagesList, BasePage);
break;
case LoaderXIPRom:
/* This memory range contains Read-Only Memory (ROM) */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current ROM page */
Pfn = GetPfnEntry(BasePage + PageNumber);
/* Initialize the PFN entry to represent a ROM page */
Pfn->PteAddress = 0;
Pfn->u1.Flink = 0;
Pfn->u2.ShareCount = 0;
Pfn->u3.e1.CacheAttribute = PfnNonCached;
Pfn->u3.e1.PageLocation = 0;
Pfn->u3.e1.PrototypePte = 1;
Pfn->u3.e1.Rom = 1;
Pfn->u3.e2.ReferenceCount = 0;
Pfn->u4.InPageError = 0;
Pfn->u4.PteFrame = 0;
}
break;
default:
/* All other types are considered in-use (ie, by the kernel, ACPI, etc) */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current in-use page */
Pfn = GetPfnEntry(BasePage + PageNumber);
/* Mark the PFN as active and valid to prevent it from being allocated */
Pfn->u3.e1.PageLocation = ActiveAndValid;
}
break;
}
}
}
/**
* Recursively scans a page table to initialize PFN database entries for active pages.
*

84
xtoskrnl/mm/pfn.cc
View File

@@ -949,90 +949,6 @@ MM::Pfn::LinkStandbyPage(IN PFN_NUMBER PageFrameIndex)
IncrementAvailablePages();
}
/**
* Processes a memory descriptor and initializes the corresponding PFN database entries
*
* @param BasePage
* The starting physical page number of the memory run
*
* @param PageCount
* The number of pages in the memory run
*
* @param MemoryType
* The type of memory as reported by the bootloader (e.g., free, ROM, in-use)
*
* @return This routine does not return any value.
*
* @since XT 1.0
*/
XTAPI
VOID
MM::Pfn::ProcessMemoryDescriptor(IN PFN_NUMBER BasePage,
IN PFN_NUMBER PageCount,
IN LOADER_MEMORY_TYPE MemoryType)
{
PFN_NUMBER CurrentPage, PageNumber;
PMMPFN Pfn;
/* Check if the memory descriptor describes a free memory region */
if(MM::Manager::VerifyMemoryTypeFree(MemoryType))
{
/* Iterate over each page in this free memory run */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current page and set its initial cache attribute */
CurrentPage = BasePage + PageNumber;
Pfn = GetPfnEntry(CurrentPage);
Pfn->u3.e1.CacheAttribute = PfnNonCached;
/* Add the page to the free list to make it available for allocation */
LinkFreePage(CurrentPage);
}
}
else
{
/* Handle all other (non-free) memory types */
switch(MemoryType)
{
case LoaderBad:
/* This memory is marked as bad and should not be used, add it to the bad pages list */
LinkPage(&BadPagesList, BasePage);
break;
case LoaderXIPRom:
/* This memory range contains Read-Only Memory (ROM) */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current ROM page */
Pfn = GetPfnEntry(BasePage + PageNumber);
/* Initialize the PFN entry to represent a ROM page */
Pfn->PteAddress = 0;
Pfn->u1.Flink = 0;
Pfn->u2.ShareCount = 0;
Pfn->u3.e1.CacheAttribute = PfnNonCached;
Pfn->u3.e1.PageLocation = 0;
Pfn->u3.e1.PrototypePte = 1;
Pfn->u3.e1.Rom = 1;
Pfn->u3.e2.ReferenceCount = 0;
Pfn->u4.InPageError = 0;
Pfn->u4.PteFrame = 0;
}
break;
default:
/* All other types are considered in-use (ie, by the kernel, ACPI, etc) */
for(PageNumber = 0; PageNumber < PageCount; PageNumber++)
{
/* Get the PFN entry for the current in-use page */
Pfn = GetPfnEntry(BasePage + PageNumber);
/* Mark the PFN as active and valid to prevent it from being allocated */
Pfn->u3.e1.PageLocation = ActiveAndValid;
}
break;
}
}
}
/**
* Scans memory descriptors provided by the boot loader.
*