BOOLEAN MmAreMemoryPagesAvailable(PVOID PageLookupTable, ULONG TotalPageCount, PVOID PageAddress, ULONG PageCount)
{
PPAGE_LOOKUP_TABLE_ITEM RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTable;
ULONG StartPage;
ULONG Index;
StartPage = MmGetPageNumberFromAddress(PageAddress);
StartPage -= MmLowestPhysicalPage;
// Make sure they aren't trying to go past the
// end of availabe memory
if ((StartPage + PageCount) > TotalPageCount)
{
return FALSE;
}
for (Index=StartPage; Index<(StartPage + PageCount); Index++)
{
// If this page is allocated then there obviously isn't
// memory availabe so return FALSE
if (RealPageLookupTable[Index].PageAllocated != LoaderFree)
{
return FALSE;
}
}
return TRUE;
}
VOID MmInitPageLookupTable(PVOID PageLookupTable, PFN_NUMBER TotalPageCount)
{
const FREELDR_MEMORY_DESCRIPTOR* MemoryDescriptor = NULL;
PFN_NUMBER PageLookupTableStartPage;
PFN_NUMBER PageLookupTablePageCount;
TRACE("MmInitPageLookupTable()\n");
// Mark every page as allocated initially
// We will go through and mark pages again according to the memory map
// But this will mark any holes not described in the map as allocated
MmMarkPagesInLookupTable(PageLookupTable, MmLowestPhysicalPage, TotalPageCount, LoaderFirmwarePermanent);
// Parse the whole memory map
while ((MemoryDescriptor = ArcGetMemoryDescriptor(MemoryDescriptor)) != NULL)
{
// Mark used pages in the lookup table
if (MemoryDescriptor->BasePage + MemoryDescriptor->PageCount <= TotalPageCount)
{
TRACE("Marking pages 0x%lx-0x%lx as type %s\n",
MemoryDescriptor->BasePage,
MemoryDescriptor->BasePage + MemoryDescriptor->PageCount,
MmGetSystemMemoryMapTypeString(MemoryDescriptor->MemoryType));
MmMarkPagesInLookupTable(PageLookupTable,
MemoryDescriptor->BasePage,
MemoryDescriptor->PageCount,
MemoryDescriptor->MemoryType);
}
else
TRACE("Ignoring pages 0x%lx-0x%lx (%s)\n",
MemoryDescriptor->BasePage,
MemoryDescriptor->BasePage + MemoryDescriptor->PageCount,
MmGetSystemMemoryMapTypeString(MemoryDescriptor->MemoryType));
}
// Mark the pages that the lookup table occupies as reserved
PageLookupTableStartPage = MmGetPageNumberFromAddress(PageLookupTable);
PageLookupTablePageCount = MmGetPageNumberFromAddress((PVOID)((ULONG_PTR)PageLookupTable + ROUND_UP(TotalPageCount * sizeof(PAGE_LOOKUP_TABLE_ITEM), MM_PAGE_SIZE))) - PageLookupTableStartPage;
TRACE("Marking the page lookup table pages as reserved StartPage: 0x%x PageCount: 0x%x\n", PageLookupTableStartPage, PageLookupTablePageCount);
MmMarkPagesInLookupTable(PageLookupTable, PageLookupTableStartPage, PageLookupTablePageCount, LoaderFirmwareTemporary);
}
VOID MmInitPageLookupTable(PVOID PageLookupTable, ULONG TotalPageCount)
{
const MEMORY_DESCRIPTOR* MemoryDescriptor = NULL;
TYPE_OF_MEMORY MemoryMapPageAllocated;
ULONG PageLookupTableStartPage;
ULONG PageLookupTablePageCount;
TRACE("MmInitPageLookupTable()\n");
//
// Mark every page as allocated initially
// We will go through and mark pages again according to the memory map
// But this will mark any holes not described in the map as allocated
//
MmMarkPagesInLookupTable(PageLookupTable, MmLowestPhysicalPage, TotalPageCount, LoaderFirmwarePermanent);
//
// Parse the whole memory map
//
while ((MemoryDescriptor = ArcGetMemoryDescriptor(MemoryDescriptor)) != NULL)
{
//
// Convert ARC memory type to loader memory type
//
switch (MemoryDescriptor->MemoryType)
{
case MemoryFree:
{
//
// Allocatable memory
//
MemoryMapPageAllocated = LoaderFree;
break;
}
case MemoryFirmwarePermanent:
{
//
// Firmware permanent memory
//
MemoryMapPageAllocated = LoaderFirmwarePermanent;
break;
}
case MemoryFirmwareTemporary:
{
//
// Firmware temporary memory
//
MemoryMapPageAllocated = LoaderFirmwareTemporary;
break;
}
case MemoryLoadedProgram:
{
//
// Bootloader code
//
MemoryMapPageAllocated = LoaderLoadedProgram;
break;
}
case MemorySpecialMemory:
{
//
// OS Loader Stack
//
MemoryMapPageAllocated = LoaderOsloaderStack;
break;
}
default:
{
//
// Put something sensible here, which won't be overwritten
//
MemoryMapPageAllocated = LoaderSpecialMemory;
break;
}
}
//
// Mark used pages in the lookup table
//
TRACE("Marking pages as type %d: StartPage: %d PageCount: %d\n", MemoryMapPageAllocated, MemoryDescriptor->BasePage, MemoryDescriptor->PageCount);
MmMarkPagesInLookupTable(PageLookupTable, MemoryDescriptor->BasePage, MemoryDescriptor->PageCount, MemoryMapPageAllocated);
}
//
// Mark the pages that the lookup table occupies as reserved
//
PageLookupTableStartPage = MmGetPageNumberFromAddress(PageLookupTable);
PageLookupTablePageCount = MmGetPageNumberFromAddress((PVOID)((ULONG_PTR)PageLookupTable + ROUND_UP(TotalPageCount * sizeof(PAGE_LOOKUP_TABLE_ITEM), MM_PAGE_SIZE))) - PageLookupTableStartPage;
TRACE("Marking the page lookup table pages as reserved StartPage: %d PageCount: %d\n", PageLookupTableStartPage, PageLookupTablePageCount);
MmMarkPagesInLookupTable(PageLookupTable, PageLookupTableStartPage, PageLookupTablePageCount, LoaderFirmwareTemporary);
}
