X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86_64%2Fmm_phys.c;h=062b138714cf6a5000107b663b80ca593ad5e93c;hb=dec96d539a700885bace43218e26f684934a1a01;hp=5a5f5eabe635e042388bf159e1b72fa88f8e1049;hpb=d8b11d2074b48f17f999d44c75b1f76fdffd970b;p=tpg%2Facess2.git

diff --git a/Kernel/arch/x86_64/mm_phys.c b/Kernel/arch/x86_64/mm_phys.c
index 5a5f5eab..062b1387 100644
--- a/Kernel/arch/x86_64/mm_phys.c
+++ b/Kernel/arch/x86_64/mm_phys.c
@@ -3,6 +3,7 @@
  * 
  * Physical Memory Manager
  */
+#define DEBUG	0
 #include <acess.h>
 #include <mboot.h>
 #include <mm_virt.h>
@@ -18,38 +19,61 @@ enum eMMPhys_Ranges
 };
 
 // === IMPORTS ===
-extern void	gKernelEnd;
+extern char	gKernelBase[];
+extern char	gKernelEnd[];
+
+// === PROTOTYPES ===
+void	MM_InitPhys_Multiboot(tMBoot_Info *MBoot);
+//tPAddr	MM_AllocPhysRange(int Num, int Bits);
+//tPAddr	MM_AllocPhys(void);
+//void	MM_RefPhys(tPAddr PAddr);
+//void	MM_DerefPhys(tPAddr PAddr);
+ int	MM_int_GetRangeID( tPAddr Addr );
 
 // === GLOBALS ===
-tSpinlock	glPhysicalPages;
-Uint64	*gaSuperBitmap;	// 1 bit = 64 Pages
+tMutex	glPhysicalPages;
+Uint64	*gaSuperBitmap = (void*)MM_PAGE_SUPBMP;	// 1 bit = 64 Pages, 16 MiB Per Word
+Uint64	*gaMainBitmap = (void*)MM_PAGE_BITMAP;	// 1 bit = 1 Page, 256 KiB per Word
+Uint64	*gaMultiBitmap = (void*)MM_PAGE_DBLBMP;	// Each bit means that the page is being used multiple times
 Uint32	*gaiPageReferences = (void*)MM_PAGE_COUNTS;	// Reference Counts
 tPAddr	giFirstFreePage;	// First possibly free page
 Uint64	giPhysRangeFree[NUM_MM_PHYS_RANGES];	// Number of free pages in each range
 Uint64	giPhysRangeFirst[NUM_MM_PHYS_RANGES];	// First free page in each range
 Uint64	giPhysRangeLast[NUM_MM_PHYS_RANGES];	// Last free page in each range
 Uint64	giMaxPhysPage = 0;	// Maximum Physical page
+// Only used in init, allows the init code to provide pages for use by
+// the allocator before the bitmaps exist.
+// 3 entries because the are three calls to MM_AllocPhys in MM_Map
+#define NUM_STATIC_ALLOC	3
+tPAddr	gaiStaticAllocPages[NUM_STATIC_ALLOC] = {0};
 
 // === CODE ===
+/**
+ * \brief Initialise the physical memory map using a Multiboot 1 map
+ */
 void MM_InitPhys_Multiboot(tMBoot_Info *MBoot)
 {
 	tMBoot_MMapEnt	*mmapStart;
 	tMBoot_MMapEnt	*ent;
 	Uint64	maxAddr = 0;
-	 int	numPages;
+	 int	numPages, superPages;
+	 int	i;
+	Uint64	base, size;
+	tVAddr	vaddr;
+	tPAddr	paddr, firstFreePage;
 	
-	Log("MM_InitPhys_Multiboot: (MBoot=%p)", MBoot);
+	ENTER("pMBoot=%p", MBoot);
 	
 	// Scan the physical memory map
 	// Looking for the top of physical memory
 	mmapStart = (void *)( KERNEL_BASE | MBoot->MMapAddr );
-	Log(" MM_InitPhys_Multiboot: mmapStart = %p", mmapStart);
+	LOG("mmapStart = %p", mmapStart);
 	ent = mmapStart;
 	while( (Uint)ent < (Uint)mmapStart + MBoot->MMapLength )
 	{
 		// Adjust for the size of the entry
 		ent->Size += 4;
-		Log(" MM_InitPhys_Multiboot: ent={Type:%i,Base:0x%x,Length:%x",
+		LOG("ent={Type:%i,Base:0x%x,Length:%x",
 			ent->Type, ent->Base, ent->Length);
 		
 		// If entry is RAM and is above `maxAddr`, change `maxAddr`
@@ -69,42 +93,128 @@ void MM_InitPhys_Multiboot(tMBoot_Info *MBoot)
 		// Goodie, goodie gumdrops
 		giMaxPhysPage = maxAddr >> 12;
 	}
-	Log(" MM_InitPhys_Multiboot: giMaxPhysPage = 0x%x", giMaxPhysPage);
+	LOG("giMaxPhysPage = 0x%x", giMaxPhysPage);
 	
 	// Find a contigous section of memory to hold it in
 	// - Starting from the end of the kernel
 	// - We also need a region for the super bitmap
-	numPages = (giMaxPhysPage + 7) * sizeof(*gaiPageReferences);
+	superPages = ((giMaxPhysPage+64*8-1)/(64*8) + 0xFFF) >> 12;
+	numPages = (giMaxPhysPage + 7) / 8;
 	numPages = (numPages + 0xFFF) >> 12;
-	Log(" MM_InitPhys_Multiboot: numPages = %i", numPages);
+	LOG("numPages = %i, superPages = %i", numPages, superPages);
 	if(maxAddr == 0)
 	{
+		 int	todo = numPages*2 + superPages;
 		// Ok, naieve allocation, just put it after the kernel
-		tVAddr	vaddr = MM_PAGE_COUNTS;
-		tPAddr	paddr = (tPAddr)&gKernelEnd - KERNEL_BASE;
-		while(numPages --)
+		// - Allocated Bitmap
+		vaddr = MM_PAGE_BITMAP;
+		paddr = (tPAddr)&gKernelEnd - KERNEL_BASE;
+		while(todo )
 		{
+			// Allocate statics
+			for( i = 0; i < NUM_STATIC_ALLOC; i++) {
+				if(gaiStaticAllocPages[i] != 0)	continue;
+				gaiStaticAllocPages[i] = paddr;
+				paddr += 0x1000;
+			}
+			
 			MM_Map(vaddr, paddr);
 			vaddr += 0x1000;
 			paddr += 0x1000;
+			
+			todo --;
+			
+			if( todo == numPages + superPages )
+				vaddr = MM_PAGE_DBLBMP;
+			if( todo == superPages )
+				vaddr = MM_PAGE_SUPBMP;
 		}
-		// Allocate the super bitmap
-		gaSuperBitmap = (void*) MM_MapHWPages(
-			paddr,
-			((giMaxPhysPage+64*8-1)/(64*8) + 0xFFF) >> 12
-			);
 	}
 	// Scan for a nice range
 	else
 	{
-		
+		 int	todo = numPages*2 + superPages;
+		paddr = 0;
+		vaddr = MM_PAGE_BITMAP;
+		// Scan!
+		for(
+			ent = mmapStart;
+			(Uint)ent < (Uint)mmapStart + MBoot->MMapLength;
+			ent = (tMBoot_MMapEnt *)( (Uint)ent + ent->Size )
+			)
+		{
+			 int	avail;
+			
+			// RAM only please
+			if( ent->Type != 1 )
+				continue;
+			
+			// Let's not put it below the kernel, shall we?
+			if( ent->Base + ent->Size < (tPAddr)&gKernelBase )
+				continue;
+			
+			LOG("%x <= %x && %x > %x",
+				ent->Base, (tPAddr)&gKernelBase,
+				ent->Base + ent->Size, (tPAddr)&gKernelEnd - KERNEL_BASE
+				);
+			// Check if the kernel is in this range
+			if( ent->Base <= (tPAddr)&gKernelBase
+			&& ent->Base + ent->Length > (tPAddr)&gKernelEnd - KERNEL_BASE )
+			{
+				avail = ent->Length >> 12;
+				avail -= ((tPAddr)&gKernelEnd - KERNEL_BASE - ent->Base) >> 12;
+				paddr = (tPAddr)&gKernelEnd - KERNEL_BASE;
+			}
+			// No? then we can use all of the block
+			else
+			{
+				avail = ent->Length >> 12;
+				paddr = ent->Base;
+			}
+			
+			Log(" MM_InitPhys_Multiboot: paddr=0x%x, avail=%i", paddr, avail);
+			
+			// Map
+			while( todo && avail --)
+			{
+				// Static Allocations
+				for( i = 0; i < NUM_STATIC_ALLOC && avail; i++) {
+					if(gaiStaticAllocPages[i] != 0)	continue;
+					gaiStaticAllocPages[i] = paddr;
+					paddr += 0x1000;
+					avail --;
+				}
+				if(!avail)	break;
+				
+				// Map
+				MM_Map(vaddr, paddr);
+				todo --;
+				vaddr += 0x1000;
+				paddr += 0x1000;
+				
+				// Alter the destination address when needed
+				if(todo == superPages+numPages)
+					vaddr = MM_PAGE_DBLBMP;
+				if(todo == superPages)
+					vaddr = MM_PAGE_SUPBMP;
+			}
+			
+			// Fast quit if there's nothing left to allocate
+			if( !todo )		break;
+		}
 	}
+	// Save the current value of paddr to simplify the allocation later
+	firstFreePage = paddr;
 	
+	LOG("Clearing multi bitmap");
 	// Fill the bitmaps
+	memset(gaMultiBitmap, 0, (numPages<<12)/8);
 	// - initialise to one, then clear the avaliable areas
-	memset(gaSuperBitmap, -1, (giMaxPhysPage+64*8-1)/(64*8));
-	memset(gaiPageReferences, -1, giMaxPhysPage*sizeof(*gaiPageReferences));
+	memset(gaMainBitmap, -1, (numPages<<12)/8);
+	memset(gaSuperBitmap, -1, (numPages<<12)/(8*64));
+	LOG("Setting main bitmap");
 	// - Clear all Type=1 areas
+	LOG("Clearing valid regions");
 	for(
 		ent = mmapStart;
 		(Uint)ent < (Uint)mmapStart + MBoot->MMapLength;
@@ -113,105 +223,180 @@ void MM_InitPhys_Multiboot(tMBoot_Info *MBoot)
 	{
 		// Check if the type is RAM
 		if(ent->Type != 1)	continue;
-		// Clear the range
-		memset(
-			&gaiPageReferences[ ent->Base >> 12 ],
-			0,
-			(ent->Size>>12)*sizeof(*gaiPageReferences)
-			);
+		
+		// Main bitmap
+		base = ent->Base >> 12;
+		size = ent->Size >> 12;
+		
+		if(base & 63) {
+			Uint64	val = -1LL << (base & 63);
+			gaMainBitmap[base / 64] &= ~val;
+			size -= (base & 63);
+			base += 64 - (base & 63);
+		}
+		memset( &gaMainBitmap[base / 64], 0, size/8 );
+		if( size & 7 ) {
+			Uint64	val = -1LL << (size & 7);
+			val <<= (size/8)&7;
+			gaMainBitmap[base / 64] &= ~val;
+		}
+		
+		// Super Bitmap
+		base = ent->Base >> 12;
+		size = ent->Size >> 12;
+		size = (size + (base & 63) + 63) >> 6;
+		base = base >> 6;
+		if(base & 63) {
+			Uint64	val = -1LL << (base & 63);
+			gaSuperBitmap[base / 64] &= ~val;
+			size -= (base & 63);
+			base += 64 - (base & 63);
+		}
+	}
+	
+	// Reference the used pages
+	base = (tPAddr)&gKernelBase >> 12;
+	size = firstFreePage >> 12;
+	memset( &gaMainBitmap[base / 64], -1, size/8 );
+	if( size & 7 ) {
+		Uint64	val = -1LL << (size & 7);
+		val <<= (size/8)&7;
+		gaMainBitmap[base / 64] |= val;
+	}
+	
+	// Free the unused static allocs
+	for( i = 0; i < NUM_STATIC_ALLOC; i++) {
+		if(gaiStaticAllocPages[i] != 0)
+			continue;
+		gaMainBitmap[ gaiStaticAllocPages[i] >> (12+6) ]
+			&= ~(1LL << ((gaiStaticAllocPages[i]>>12)&63));
+	}
+	
+	// Fill the super bitmap
+	LOG("Filling super bitmap");
+	memset(gaSuperBitmap, 0, superPages<<12);
+	for( base = 0; base < (size+63)/64; base ++)
+	{
+		if( gaMainBitmap[ base ] + 1 == 0 )
+			gaSuperBitmap[ base/64 ] |= 1LL << (base&63);
+	}
+	
+	// Set free page counts
+	for( base = 1; base < giMaxPhysPage; base ++ )
+	{
+		 int	rangeID;
+		// Skip allocated
+		if( gaMainBitmap[ base >> 6 ] & (1LL << (base&63))  )	continue;
+		
+		// Get range ID
+		rangeID = MM_int_GetRangeID( base << 12 );
+		
+		// Increment free page count
+		giPhysRangeFree[ rangeID ] ++;
+		
+		// Check for first free page in range
+		if(giPhysRangeFirst[ rangeID ] == 0)
+			giPhysRangeFirst[ rangeID ] = base;
+		// Set last (when the last free page is reached, this won't be
+		// updated anymore, hence will be correct)
+		giPhysRangeLast[ rangeID ] = base;
 	}
+	
+	LEAVE('-');
 }
 
 /**
  * \brief Allocate a contiguous range of physical pages with a maximum
- *        bit size of \a Bits
- * \param Num	Number of pages to allocate
- * \param Bits	Maximum size of the physical address
- * \note If \a Bits is <= 0, any sized address is used (with preference
+ *        bit size of \a MaxBits
+ * \param Pages	Number of pages to allocate
+ * \param MaxBits	Maximum size of the physical address
+ * \note If \a MaxBits is <= 0, any sized address is used (with preference
  *       to higher addresses)
  */
-tPAddr MM_AllocPhysRange(int Num, int Bits)
+tPAddr MM_AllocPhysRange(int Pages, int MaxBits)
 {
-	tPAddr	addr;
+	tPAddr	addr, ret;
 	 int	rangeID;
 	 int	nFree = 0, i;
 	
-	Log("MM_AllocPhysRange: (Num=%i,Bits=%i)", Num, Bits);
+	ENTER("iPages iBits", Pages, MaxBits);
 	
-	if( Bits <= 0 )	// Speedup for the common case
-		rangeID = MM_PHYS_MAX;
-	else if( Bits > 32 )
+	if( MaxBits <= 0 || MaxBits >= 64 )	// Speedup for the common case
 		rangeID = MM_PHYS_MAX;
-	else if( Bits > 24 )
-		rangeID = MM_PHYS_32BIT;
-	else if( Bits > 20 )
-		rangeID = MM_PHYS_24BIT;
-	else if( Bits > 16 )
-		rangeID = MM_PHYS_20BIT;
 	else
-		rangeID = MM_PHYS_16BIT;
+		rangeID = MM_int_GetRangeID( (1LL << MaxBits) - 1 );
 	
-	Log(" MM_AllocPhysRange: rangeID = %i", rangeID);
+	LOG("rangeID = %i", rangeID);
 	
-	LOCK(&glPhysicalPages);
-	Log(" MM_AllocPhysRange: i has lock");
+	Mutex_Acquire(&glPhysicalPages);
 	
 	// Check if the range actually has any free pages
 	while(giPhysRangeFree[rangeID] == 0 && rangeID)
 		rangeID --;
 	
-	Log(" MM_AllocPhysRange: rangeID = %i", rangeID);
+	LOG("rangeID = %i", rangeID);
 	
 	// What the? Oh, man. No free pages
 	if(giPhysRangeFree[rangeID] == 0) {
-		RELEASE(&glPhysicalPages);
+		Mutex_Release(&glPhysicalPages);
 		// TODO: Page out
 		// ATM. Just Warning
 		Warning(" MM_AllocPhysRange: Out of free pages");
 		Log_Warning("Arch",
 			"Out of memory (unable to fulfil request for %i pages), zero remaining",
-			Num
+			Pages
 			);
+		LEAVE('i', 0);
 		return 0;
 	}
 	
 	// Check if there is enough in the range
-	if(giPhysRangeFree[rangeID] >= Num)
+	if(giPhysRangeFree[rangeID] >= Pages)
 	{
+		LOG("{%i,0x%x -> 0x%x}",
+			giPhysRangeFree[rangeID],
+			giPhysRangeFirst[rangeID], giPhysRangeLast[rangeID]
+			);
 		// Do a cheap scan, scanning upwards from the first free page in
 		// the range
-		nFree = 1;
+		nFree = 0;
 		addr = giPhysRangeFirst[ rangeID ];
-		while( addr < giPhysRangeLast[ rangeID ] )
+		while( addr <= giPhysRangeLast[ rangeID ] )
 		{
+			//Log(" MM_AllocPhysRange: addr = 0x%x", addr);
 			// Check the super bitmap
-			if( gaSuperBitmap[addr >> (6+6)] == -1 ) {
+			if( gaSuperBitmap[addr >> (6+6)] + 1 == 0 ) {
+				LOG("nFree = %i = 0 (super) (0x%x)", nFree, addr);
 				nFree = 0;
-				addr += 1 << (6+6);
-				addr &= (1 << (6+6)) - 1;
+				addr += 1LL << (6+6);
+				addr &= ~0xFFF;	// (1LL << 6+6) - 1
 				continue;
 			}
 			// Check page block (64 pages)
-			if( gaSuperBitmap[addr >> (6+6)] & (1 << (addr>>6)&63)) {
+			if( gaMainBitmap[addr >> 6] + 1 == 0) {
+				LOG("nFree = %i = 0 (main) (0x%x)", nFree, addr);
 				nFree = 0;
-				addr += 1 << (12+6);
-				addr &= (1 << (12+6)) - 1;
+				addr += 1LL << (6);
+				addr &= ~0x3F;
 				continue;
 			}
 			// Check individual page
-			if( gaiPageReferences[addr] ) {
+			if( gaMainBitmap[addr >> 6] & (1LL << (addr & 63)) ) {
+				LOG("nFree = %i = 0 (page) (0x%x)", nFree, addr);
 				nFree = 0;
 				addr ++;
 				continue;
 			}
 			nFree ++;
 			addr ++;
-			if(nFree == Num)
+			LOG("nFree(%i) == %i (0x%x)", nFree, Pages, addr);
+			if(nFree == Pages)
 				break;
 		}
+		LOG("nFree = %i", nFree);
 		// If we don't find a contiguous block, nFree will not be equal
 		// to Num, so we set it to zero and do the expensive lookup.
-		if(nFree != Num)	nFree = 0;
+		if(nFree != Pages)	nFree = 0;
 	}
 	
 	if( !nFree )
@@ -221,49 +406,45 @@ tPAddr MM_AllocPhysRange(int Num, int Bits)
 		nFree = 1;
 		addr = giPhysRangeLast[ rangeID ];
 		// TODO
-		RELEASE(&glPhysicalPages);
+		Mutex_Release(&glPhysicalPages);
 		// TODO: Page out
 		// ATM. Just Warning
+		Warning(" MM_AllocPhysRange: Out of memory (unable to fulfil request for %i pages)", Pages);
 		Log_Warning("Arch",
 			"Out of memory (unable to fulfil request for %i pages)",
-			Num
+			Pages	
 			);
+		LEAVE('i', 0);
 		return 0;
 	}
-	Log(" MM_AllocPhysRange: nFree = %i, addr = 0x%08x", nFree, addr);
+	LOG("nFree = %i, addr = 0x%08x", nFree, addr);
 	
 	// Mark pages as allocated
-	addr -= Num;
-	for( i = 0; i < Num; i++ )
+	addr -= Pages;
+	for( i = 0; i < Pages; i++, addr++ )
 	{
-		gaiPageReferences[addr] = 1;
-		
-		     if(addr >> 32)	rangeID = MM_PHYS_MAX;
-		else if(addr >> 24)	rangeID = MM_PHYS_32BIT;
-		else if(addr >> 20)	rangeID = MM_PHYS_24BIT;
-		else if(addr >> 16)	rangeID = MM_PHYS_20BIT;
-		else if(addr >> 0)	rangeID = MM_PHYS_16BIT;
+		gaMainBitmap[addr >> 6] |= 1LL << (addr & 63);
+		rangeID = MM_int_GetRangeID(addr << 12);
 		giPhysRangeFree[ rangeID ] --;
+		LOG("%x == %x", addr, giPhysRangeFirst[ rangeID ]);
+		if(addr == giPhysRangeFirst[ rangeID ])
+			giPhysRangeFirst[ rangeID ] += 1;
 	}
-	// Fill super bitmap
-	Num += addr & (64-1);
+	ret = addr;	// Save the return address
+	
+	// Update super bitmap
+	Pages += addr & (64-1);
 	addr &= ~(64-1);
-	Num = (Num + (64-1)) & ~(64-1);
-	for( i = 0; i < Num/64; i++ )
+	Pages = (Pages + (64-1)) & ~(64-1);
+	for( i = 0; i < Pages/64; i++ )
 	{
-		 int	j, bFull = 1;
-		for( j = 0; j < 64; j ++ ) {
-			if( gaiPageReferences[addr+i*64+j] ) {
-				bFull = 0;
-				break;
-			}
-		}
-		if( bFull )
-			gaSuperBitmap[addr>>12] |= 1 << ((addr >> 6) & 64);
+		if( gaMainBitmap[ addr >> 6 ] + 1 == 0 )
+			gaSuperBitmap[addr>>12] |= 1LL << ((addr >> 6) & 63);
 	}
 	
-	RELEASE(&glPhysicalPages);
-	return addr << 12;
+	Mutex_Release(&glPhysicalPages);
+	LEAVE('x', ret << 12);
+	return ret << 12;
 }
 
 /**
@@ -272,6 +453,18 @@ tPAddr MM_AllocPhysRange(int Num, int Bits)
  */
 tPAddr MM_AllocPhys(void)
 {
+	 int	i;
+	
+	// Hack to allow allocation during setup
+	for(i = 0; i < NUM_STATIC_ALLOC; i++) {
+		if( gaiStaticAllocPages[i] ) {
+			tPAddr	ret = gaiStaticAllocPages[i];
+			gaiStaticAllocPages[i] = 0;
+			Log("MM_AllocPhys: Return %x, static alloc %i", ret, i);
+			return ret;
+		}
+	}
+	
 	return MM_AllocPhysRange(1, -1);
 }
 
@@ -280,19 +473,23 @@ tPAddr MM_AllocPhys(void)
  */
 void MM_RefPhys(tPAddr PAddr)
 {
-	 int	bIsFull, j;
+	Uint64	page = PAddr >> 12;
+	
 	if( PAddr >> 12 > giMaxPhysPage )	return ;
-	gaiPageReferences[ PAddr >> 12 ] ++;
 	
-	bIsFull = 1;
-	for( j = 0; j < 64; j++ ) {
-		if( gaiPageReferences[ PAddr >> 12 ] == 0 ) {
-			bIsFull = 0;
-			break;
-		}
+	if( gaMainBitmap[ page >> 6 ] & (1LL << (page&63)) )
+	{
+		// Reference again
+		gaMultiBitmap[ page >> 6 ] |= 1LL << (page&63);
+		gaiPageReferences[ page ] ++;
+	}
+	else
+	{
+		// Allocate
+		gaMainBitmap[page >> 6] |= 1LL << (page&63);
+		if( gaMainBitmap[page >> 6 ] + 1 == 0 )
+			gaSuperBitmap[page>> 12] |= 1LL << ((page >> 6) & 63);
 	}
-	if( bIsFull )
-		gaSuperBitmap[PAddr >> 24] |= 1 << ((PAddr >> 18) & 64);
 }
 
 /**
@@ -300,10 +497,53 @@ void MM_RefPhys(tPAddr PAddr)
  */
 void MM_DerefPhys(tPAddr PAddr)
 {
+	Uint64	page = PAddr >> 12;
+	
 	if( PAddr >> 12 > giMaxPhysPage )	return ;
-	gaiPageReferences[ PAddr >> 12 ] --;
-	if( gaiPageReferences[ PAddr >> 12 ] )
+	
+	if( gaMultiBitmap[ page >> 6 ] & (1LL << (page&63)) ) {
+		gaiPageReferences[ page ] --;
+		if( gaiPageReferences[ page ] == 1 )
+			gaMultiBitmap[ page >> 6 ] &= ~(1LL << (page&63));
+		if( gaiPageReferences[ page ] == 0 )
+			gaMainBitmap[ page >> 6 ] &= ~(1LL << (page&63));
+	}
+	else
+		gaMainBitmap[ page >> 6 ] &= ~(1LL << (page&63));
+	
+	// Update the free counts if the page was freed
+	if( !(gaMainBitmap[ page >> 6 ] & (1LL << (page&63))) )
 	{
-		gaSuperBitmap[PAddr >> 24] &= ~(1 << ((PAddr >> 18) & 64));
+		 int	rangeID;
+		rangeID = MM_int_GetRangeID( PAddr );
+		giPhysRangeFree[ rangeID ] ++;
+		if( giPhysRangeFirst[rangeID] > page )
+			giPhysRangeFirst[rangeID] = page;
+		if( giPhysRangeLast[rangeID] < page )
+			giPhysRangeLast[rangeID] = page;
 	}
+	
+	// If the bitmap entry is not -1, unset the bit in the super bitmap
+	if(gaMainBitmap[ page >> 6 ] + 1 != 0 ) {
+		gaSuperBitmap[page >> 12] &= ~(1LL << ((page >> 6) & 63));
+	}
+}
+
+/**
+ * \brief Takes a physical address and returns the ID of its range
+ * \param Addr	Physical address of page
+ * \return Range ID from eMMPhys_Ranges
+ */
+int MM_int_GetRangeID( tPAddr Addr )
+{
+	if(Addr >> 32)
+		return MM_PHYS_MAX;
+	else if(Addr >> 24)
+		return MM_PHYS_32BIT;
+	else if(Addr >> 20)
+		return MM_PHYS_24BIT;
+	else if(Addr >> 16)
+		return MM_PHYS_20BIT;
+	else
+		return MM_PHYS_16BIT;
 }