mm.c File Reference

#include <freeldr.h>
#include <debug.h>

Include dependency graph for mm.c:

Go to the source code of this file.

Functions
	DBG_DEFAULT_CHANNEL (MEMORY)
PVOID	MmAllocateMemoryWithType (SIZE_T MemorySize, TYPE_OF_MEMORY MemoryType)
PVOID	MmAllocateMemoryAtAddress (SIZE_T MemorySize, PVOID DesiredAddress, TYPE_OF_MEMORY MemoryType)
VOID	MmSetMemoryType (PVOID MemoryAddress, SIZE_T MemorySize, TYPE_OF_MEMORY NewType)
PVOID	MmAllocateHighestMemoryBelowAddress (SIZE_T MemorySize, PVOID DesiredAddress, TYPE_OF_MEMORY MemoryType)
VOID	MmFreeMemory (PVOID MemoryPointer)
PPAGE_LOOKUP_TABLE_ITEM	MmGetMemoryMap (PFN_NUMBER *NoEntries)

Variables
PFN_NUMBER	LoaderPagesSpanned = 0

Function Documentation

DBG_DEFAULT_CHANNEL()

DBG_DEFAULT_CHANNEL

(

MEMORY

)

MmAllocateHighestMemoryBelowAddress()

PVOID MmAllocateHighestMemoryBelowAddress	(	SIZE_T	MemorySize,
		PVOID	DesiredAddress,
		TYPE_OF_MEMORY	MemoryType
	)

Definition at line 160 of file mm.c.

{
    PFN_NUMBER        PagesNeeded;
    PFN_NUMBER        FirstFreePageFromEnd;
    PFN_NUMBER        DesiredAddressPageNumber;
    PVOID    MemPointer;
 
    if (MemorySize == 0)
    {
        WARN("MmAllocateHighestMemoryBelowAddress() called for 0 bytes. Returning NULL.\n");
        UiMessageBoxCritical("Memory allocation failed: MmAllocateHighestMemoryBelowAddress() called for 0 bytes.");
        return NULL;
    }
 
    // Find out how many blocks it will take to
    // satisfy this allocation
    PagesNeeded = ROUND_UP(MemorySize, MM_PAGE_SIZE) / MM_PAGE_SIZE;
 
    // Get the page number for their desired address
    DesiredAddressPageNumber = (ULONG_PTR)DesiredAddress / MM_PAGE_SIZE;
 
    // If we don't have enough available mem
    // then return NULL
    if (FreePagesInLookupTable < PagesNeeded)
    {
        ERR("Memory allocation failed in MmAllocateHighestMemoryBelowAddress(). Not enough free memory to allocate %d bytes.\n", MemorySize);
        UiMessageBoxCritical("Memory allocation failed: out of memory.");
        return NULL;
    }
 
    FirstFreePageFromEnd = MmFindAvailablePagesBeforePage(PageLookupTableAddress, TotalPagesInLookupTable, PagesNeeded, DesiredAddressPageNumber);
 
    if (FirstFreePageFromEnd == 0)
    {
        ERR("Memory allocation failed in MmAllocateHighestMemoryBelowAddress(). Not enough free memory to allocate %d bytes.\n", MemorySize);
        UiMessageBoxCritical("Memory allocation failed: out of memory.");
        return NULL;
    }
 
    MmAllocatePagesInLookupTable(PageLookupTableAddress, FirstFreePageFromEnd, PagesNeeded, MemoryType);
 
    FreePagesInLookupTable -= PagesNeeded;
    MemPointer = (PVOID)((ULONG_PTR)FirstFreePageFromEnd * MM_PAGE_SIZE);
 
    TRACE("Allocated %d bytes (%d pages) of memory starting at page %d.\n", MemorySize, PagesNeeded, FirstFreePageFromEnd);
    TRACE("Memory allocation pointer: 0x%x\n", MemPointer);
 
    // Update LoaderPagesSpanned count
    if ((((ULONG_PTR)MemPointer + MemorySize) >> PAGE_SHIFT) > LoaderPagesSpanned)
        LoaderPagesSpanned = (((ULONG_PTR)MemPointer + MemorySize) >> PAGE_SHIFT);
 
    // Now return the pointer
    return MemPointer;
}

MmAllocateMemoryAtAddress()

PVOID MmAllocateMemoryAtAddress	(	SIZE_T	MemorySize,
		PVOID	DesiredAddress,
		TYPE_OF_MEMORY	MemoryType
	)

Definition at line 85 of file mm.c.

{
    PFN_NUMBER        PagesNeeded;
    PFN_NUMBER        StartPageNumber;
    PVOID    MemPointer;
 
    if (MemorySize == 0)
    {
        WARN("MmAllocateMemoryAtAddress() called for 0 bytes. Returning NULL.\n");
        UiMessageBoxCritical("Memory allocation failed: MmAllocateMemoryAtAddress() called for 0 bytes.");
        return NULL;
    }
 
    // Find out how many blocks it will take to
    // satisfy this allocation
    PagesNeeded = ROUND_UP(MemorySize, MM_PAGE_SIZE) / MM_PAGE_SIZE;
 
    // Get the starting page number
    StartPageNumber = MmGetPageNumberFromAddress(DesiredAddress);
 
    // If we don't have enough available mem
    // then return NULL
    if (FreePagesInLookupTable < PagesNeeded)
    {
        ERR("Memory allocation failed in MmAllocateMemoryAtAddress(). "
            "Not enough free memory to allocate %d bytes (requesting %d pages but have only %d). "
            "\n", MemorySize, PagesNeeded, FreePagesInLookupTable);
        UiMessageBoxCritical("Memory allocation failed: out of memory.");
        return NULL;
    }
 
    if (MmAreMemoryPagesAvailable(PageLookupTableAddress, TotalPagesInLookupTable, DesiredAddress, PagesNeeded) == FALSE)
    {
        WARN("Memory allocation failed in MmAllocateMemoryAtAddress(). "
             "Not enough free memory to allocate %d bytes at address %p.\n",
             MemorySize, DesiredAddress);
 
        // Don't tell this to user since caller should try to alloc this memory
        // at a different address
        //UiMessageBoxCritical("Memory allocation failed: out of memory.");
        return NULL;
    }
 
    MmAllocatePagesInLookupTable(PageLookupTableAddress, StartPageNumber, PagesNeeded, MemoryType);
 
    FreePagesInLookupTable -= PagesNeeded;
    MemPointer = (PVOID)((ULONG_PTR)StartPageNumber * MM_PAGE_SIZE);
 
    TRACE("Allocated %d bytes (%d pages) of memory starting at page %d.\n", MemorySize, PagesNeeded, StartPageNumber);
    TRACE("Memory allocation pointer: 0x%x\n", MemPointer);
 
    // Update LoaderPagesSpanned count
    if ((((ULONG_PTR)MemPointer + MemorySize + PAGE_SIZE - 1) >> PAGE_SHIFT) > LoaderPagesSpanned)
        LoaderPagesSpanned = (((ULONG_PTR)MemPointer + MemorySize + PAGE_SIZE - 1) >> PAGE_SHIFT);
 
    // Now return the pointer
    return MemPointer;
}

Referenced by MempAllocatePageTables(), and PeLdrLoadImageEx().

MmAllocateMemoryWithType()

PVOID MmAllocateMemoryWithType	(	SIZE_T	MemorySize,
		TYPE_OF_MEMORY	MemoryType
	)

Definition at line 31 of file mm.c.

{
    PFN_NUMBER    PagesNeeded;
    PFN_NUMBER    FirstFreePageFromEnd;
    PVOID    MemPointer;
 
    if (MemorySize == 0)
    {
        WARN("MmAllocateMemory() called for 0 bytes. Returning NULL.\n");
        UiMessageBoxCritical("Memory allocation failed: MmAllocateMemory() called for 0 bytes.");
        return NULL;
    }
 
    MemorySize = ROUND_UP(MemorySize, 4);
 
    // Find out how many blocks it will take to
    // satisfy this allocation
    PagesNeeded = ROUND_UP(MemorySize, MM_PAGE_SIZE) / MM_PAGE_SIZE;
 
    // If we don't have enough available mem
    // then return NULL
    if (FreePagesInLookupTable < PagesNeeded)
    {
        ERR("Memory allocation failed in MmAllocateMemory(). Not enough free memory to allocate %d bytes.\n", MemorySize);
        UiMessageBoxCritical("Memory allocation failed: out of memory.");
        return NULL;
    }
 
    FirstFreePageFromEnd = MmFindAvailablePages(PageLookupTableAddress, TotalPagesInLookupTable, PagesNeeded, FALSE);
 
    if (FirstFreePageFromEnd == 0)
    {
        ERR("Memory allocation failed in MmAllocateMemory(). Not enough free memory to allocate %d bytes.\n", MemorySize);
        UiMessageBoxCritical("Memory allocation failed: out of memory.");
        return NULL;
    }
 
    MmAllocatePagesInLookupTable(PageLookupTableAddress, FirstFreePageFromEnd, PagesNeeded, MemoryType);
 
    FreePagesInLookupTable -= PagesNeeded;
    MemPointer = (PVOID)((ULONG_PTR)FirstFreePageFromEnd * MM_PAGE_SIZE);
 
    TRACE("Allocated %d bytes (%d pages) of memory (type %ld) starting at page 0x%lx.\n",
          MemorySize, PagesNeeded, MemoryType, FirstFreePageFromEnd);
    TRACE("Memory allocation pointer: 0x%x\n", MemPointer);
 
    // Update LoaderPagesSpanned count
    if ((((ULONG_PTR)MemPointer + MemorySize + PAGE_SIZE - 1) >> PAGE_SHIFT) > LoaderPagesSpanned)
        LoaderPagesSpanned = (((ULONG_PTR)MemPointer + MemorySize + PAGE_SIZE - 1) >> PAGE_SHIFT);
 
    // Now return the pointer
    return MemPointer;
}

Referenced by AllocateAndInitLPB(), EfiEntry(), FrLdrHeapCreate(), MempAllocatePageTables(), MempGetOrCreatePageDir(), PeLdrLoadImageEx(), RamDiskLoadVirtualFile(), RegLoadHiveLog(), UefiInitializeBootDevices(), UefiSetupBlockDevices(), VideoAllocateOffScreenBuffer(), WinLdrLoadModule(), WinLdrLoadNLSData(), WinLdrLoadSystemHive(), WinLdrSetupMachineDependent(), and WinLdrSetupMemoryLayout().

MmFreeMemory()

VOID MmFreeMemory

(

PVOID

MemoryPointer

)

Definition at line 215 of file mm.c.

{
}

Referenced by LoadModule(), LoadWindowsCore(), PeLdrLoadBootImage(), PeLdrLoadImageEx(), PeLdrpLoadAndScanReferencedDll(), RamDiskInitialize(), RamDiskLoadVirtualFile(), VideoFreeOffScreenBuffer(), and WinLdrLoadDeviceDriver().

MmGetMemoryMap()

PPAGE_LOOKUP_TABLE_ITEM MmGetMemoryMap

(

PFN_NUMBER *

NoEntries

)

Definition at line 297 of file mm.c.

{
    PPAGE_LOOKUP_TABLE_ITEM        RealPageLookupTable = (PPAGE_LOOKUP_TABLE_ITEM)PageLookupTableAddress;
 
    *NoEntries = TotalPagesInLookupTable;
 
    return RealPageLookupTable;
}

Referenced by WinLdrSetupMemoryLayout().

MmSetMemoryType()

VOID MmSetMemoryType	(	PVOID	MemoryAddress,
		SIZE_T	MemorySize,
		TYPE_OF_MEMORY	NewType
	)

Definition at line 144 of file mm.c.

{
    PFN_NUMBER        PagesNeeded;
    PFN_NUMBER        StartPageNumber;
 
    // Find out how many blocks it will take to
    // satisfy this allocation
    PagesNeeded = ROUND_UP(MemorySize, MM_PAGE_SIZE) / MM_PAGE_SIZE;
 
    // Get the starting page number
    StartPageNumber = MmGetPageNumberFromAddress(MemoryAddress);
 
    // Set new type for these pages
    MmAllocatePagesInLookupTable(PageLookupTableAddress, StartPageNumber, PagesNeeded, NewType);
}

Referenced by MempAllocatePageTables().

Variable Documentation

LoaderPagesSpanned

PFN_NUMBER LoaderPagesSpanned = 0

Definition at line 29 of file mm.c.

Referenced by LoadAndBootWindowsCommon(), MempSetupPagingForRegion(), MmAllocateHighestMemoryBelowAddress(), MmAllocateMemoryAtAddress(), MmAllocateMemoryWithType(), and UefiMemGetMemoryMap().