--- /dev/null
+/*
+ * Acess2 x86_64 Port
+ *
+ * Physical Memory Manager
+ */
+#define DEBUG 0
+#include <acess.h>
+#include <mboot.h>
+#include <mm_virt.h>
+
+#define TRACE_REF 0
+
+enum eMMPhys_Ranges
+{
+ MM_PHYS_16BIT, // Does anything need this?
+ MM_PHYS_20BIT, // Real-Mode
+ MM_PHYS_24BIT, // ISA DMA
+ MM_PHYS_32BIT, // x86 Hardware
+ MM_PHYS_MAX, // Doesn't care
+ NUM_MM_PHYS_RANGES
+};
+
+// === IMPORTS ===
+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 );
+
+// === MACROS ===
+#define PAGE_ALLOC_TEST(__page) (gaMainBitmap[(__page)>>6] & (1ULL << ((__page)&63)))
+#define PAGE_ALLOC_SET(__page) do{gaMainBitmap[(__page)>>6] |= (1ULL << ((__page)&63));}while(0)
+#define PAGE_ALLOC_CLEAR(__page) do{gaMainBitmap[(__page)>>6] &= ~(1ULL << ((__page)&63));}while(0)
+//#define PAGE_MULTIREF_TEST(__page) (gaMultiBitmap[(__page)>>6] & (1ULL << ((__page)&63)))
+//#define PAGE_MULTIREF_SET(__page) do{gaMultiBitmap[(__page)>>6] |= 1ULL << ((__page)&63);}while(0)
+//#define PAGE_MULTIREF_CLEAR(__page) do{gaMultiBitmap[(__page)>>6] &= ~(1ULL << ((__page)&63));}while(0)
+
+// === GLOBALS ===
+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
+void **gapPageNodes = (void*)MM_PAGE_NODES; // 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, superPages;
+ int i;
+ Uint64 base, size;
+ tVAddr vaddr;
+ tPAddr paddr, firstFreePage;
+
+ ENTER("pMBoot=%p", MBoot);
+
+ // Scan the physical memory map
+ // Looking for the top of physical memory
+ mmapStart = (void *)( KERNEL_BASE | MBoot->MMapAddr );
+ LOG("mmapStart = %p", mmapStart);
+ ent = mmapStart;
+ while( (Uint)ent < (Uint)mmapStart + MBoot->MMapLength )
+ {
+ // Adjust for the size of the entry
+ ent->Size += 4;
+ 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`
+ if(ent->Type == 1 && ent->Base + ent->Length > maxAddr)
+ maxAddr = ent->Base + ent->Length;
+
+ // Go to next entry
+ ent = (tMBoot_MMapEnt *)( (Uint)ent + ent->Size );
+ }
+
+ // Did we find a valid end?
+ if(maxAddr == 0) {
+ // No, darn, let's just use the HighMem hack
+ giMaxPhysPage = (MBoot->HighMem >> 2) + 256; // HighMem is a kByte value
+ }
+ else {
+ // Goodie, goodie gumdrops
+ giMaxPhysPage = maxAddr >> 12;
+ }
+ 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
+ superPages = ((giMaxPhysPage+64*8-1)/(64*8) + 0xFFF) >> 12;
+ numPages = (giMaxPhysPage + 7) / 8;
+ numPages = (numPages + 0xFFF) >> 12;
+ LOG("numPages = %i, superPages = %i", numPages, superPages);
+ if(maxAddr == 0)
+ {
+ int todo = numPages*2 + superPages;
+ // Ok, naieve allocation, just put it after the kernel
+ // - 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;
+ }
+ }
+ // 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=0x%x pg", 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(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;
+ ent = (tMBoot_MMapEnt *)( (Uint)ent + ent->Size )
+ )
+ {
+ // Check if the type is RAM
+ if(ent->Type != 1) continue;
+
+ // 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 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 Pages, int MaxBits)
+{
+ tPAddr addr, ret;
+ int rangeID;
+ int nFree = 0, i;
+
+ ENTER("iPages iBits", Pages, MaxBits);
+
+ if( MaxBits <= 0 || MaxBits >= 64 ) // Speedup for the common case
+ rangeID = MM_PHYS_MAX;
+ else
+ rangeID = MM_int_GetRangeID( (1LL << MaxBits) - 1 );
+
+ LOG("rangeID = %i", rangeID);
+
+ Mutex_Acquire(&glPhysicalPages);
+
+ // Check if the range actually has any free pages
+ while(giPhysRangeFree[rangeID] == 0 && rangeID)
+ rangeID --;
+
+ LOG("rangeID = %i", rangeID);
+
+ // What the? Oh, man. No free pages
+ if(giPhysRangeFree[rangeID] == 0) {
+ 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",
+ Pages
+ );
+ LEAVE('i', 0);
+ return 0;
+ }
+
+ // Check if there is enough in the range
+ 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 = 0;
+ addr = giPhysRangeFirst[ rangeID ];
+ while( addr <= giPhysRangeLast[ rangeID ] )
+ {
+ //Log(" MM_AllocPhysRange: addr = 0x%x", addr);
+ // Check the super bitmap
+ if( gaSuperBitmap[addr >> (6+6)] + 1 == 0 ) {
+ LOG("nFree = %i = 0 (super) (0x%x)", nFree, addr);
+ nFree = 0;
+ addr += 1LL << (6+6);
+ addr &= ~0xFFF; // (1LL << 6+6) - 1
+ continue;
+ }
+ // Check page block (64 pages)
+ if( gaMainBitmap[addr >> 6] + 1 == 0) {
+ LOG("nFree = %i = 0 (main) (0x%x)", nFree, addr);
+ nFree = 0;
+ addr += 1LL << (6);
+ addr &= ~0x3F;
+ continue;
+ }
+ // Check individual page
+ if( gaMainBitmap[addr >> 6] & (1LL << (addr & 63)) ) {
+ LOG("nFree = %i = 0 (page) (0x%x)", nFree, addr);
+ nFree = 0;
+ addr ++;
+ continue;
+ }
+ nFree ++;
+ addr ++;
+ 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 != Pages) nFree = 0;
+ }
+
+ if( !nFree )
+ {
+ // Oops. ok, let's do an expensive check (scan down the list
+ // until a free range is found)
+// nFree = 1;
+// addr = giPhysRangeLast[ rangeID ];
+ // TODO: Expensive Check
+ 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)",
+ Pages
+ );
+ LEAVE('i', 0);
+ return 0;
+ }
+ LOG("nFree = %i, addr = 0x%08x", nFree, addr);
+
+ // Mark pages as allocated
+ addr -= Pages;
+ for( i = 0; i < Pages; i++, addr++ )
+ {
+ gaMainBitmap[addr >> 6] |= 1LL << (addr & 63);
+ if( MM_GetPhysAddr( (tVAddr)&gaiPageReferences[addr] ) )
+ gaiPageReferences[addr] = 1;
+// Log("page %P refcount = %i", MM_GetRefCount(addr<<12));
+ rangeID = MM_int_GetRangeID(addr << 12);
+ giPhysRangeFree[ rangeID ] --;
+ LOG("%x == %x", addr, giPhysRangeFirst[ rangeID ]);
+ if(addr == giPhysRangeFirst[ rangeID ])
+ giPhysRangeFirst[ rangeID ] += 1;
+ }
+ addr -= Pages;
+ ret = addr; // Save the return address
+
+ // Update super bitmap
+ Pages += addr & (64-1);
+ addr &= ~(64-1);
+ Pages = (Pages + (64-1)) & ~(64-1);
+ for( i = 0; i < Pages/64; i++ )
+ {
+ if( gaMainBitmap[ addr >> 6 ] + 1 == 0 )
+ gaSuperBitmap[addr>>12] |= 1LL << ((addr >> 6) & 63);
+ }
+
+ Mutex_Release(&glPhysicalPages);
+ #if TRACE_REF
+ Log("MM_AllocPhysRange: ret = %P (Ref %i)", ret << 12, MM_GetRefCount(ret<<12));
+ #endif
+ LEAVE('x', ret << 12);
+ return ret << 12;
+}
+
+/**
+ * \brief Allocate a single physical page, with no preference as to address
+ * size.
+ */
+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 %P, static alloc %i", ret, i);
+ return ret;
+ }
+ }
+
+ return MM_AllocPhysRange(1, -1);
+}
+
+/**
+ * \brief Reference a physical page
+ */
+void MM_RefPhys(tPAddr PAddr)
+{
+ Uint64 page = PAddr >> 12;
+
+ if( page > giMaxPhysPage ) return ;
+
+ if( PAGE_ALLOC_TEST(page) )
+ {
+ tVAddr ref_base = ((tVAddr)&gaiPageReferences[ page ]) & ~0xFFF;
+ // Allocate reference page
+ if( !MM_GetPhysAddr(ref_base) )
+ {
+ const int pages_per_refpage = PAGE_SIZE/sizeof(gaiPageReferences[0]);
+ int i;
+ int page_base = page / pages_per_refpage * pages_per_refpage;
+ if( !MM_Allocate( ref_base ) ) {
+ Log_Error("Arch", "Out of memory when allocating reference count page");
+ return ;
+ }
+ // Fill block
+ Log("Allocated references for %P-%P", page_base << 12, (page_base+pages_per_refpage)<<12);
+ for( i = 0; i < pages_per_refpage; i ++ ) {
+ int pg = page_base + i;
+ gaiPageReferences[pg] = !!PAGE_ALLOC_TEST(pg);
+ }
+ }
+ gaiPageReferences[page] ++;
+ }
+ else
+ {
+ // Allocate
+ PAGE_ALLOC_SET(page);
+ if( gaMainBitmap[page >> 6] + 1 == 0 )
+ gaSuperBitmap[page>> 12] |= 1LL << ((page >> 6) & 63);
+ if( MM_GetPhysAddr( (tVAddr)&gaiPageReferences[page] ) )
+ gaiPageReferences[page] = 1;
+ }
+
+ #if TRACE_REF
+ Log("MM_RefPhys: %P referenced (%i)", page << 12, MM_GetRefCount(page << 12));
+ #endif
+}
+
+/**
+ * \brief Dereference a physical page
+ */
+void MM_DerefPhys(tPAddr PAddr)
+{
+ Uint64 page = PAddr >> 12;
+
+ if( PAddr >> 12 > giMaxPhysPage ) return ;
+
+ if( MM_GetPhysAddr( (tVAddr) &gaiPageReferences[page] ) )
+ {
+ gaiPageReferences[ page ] --;
+ if( gaiPageReferences[ page ] == 0 )
+ PAGE_ALLOC_CLEAR(page);
+ }
+ else
+ PAGE_ALLOC_CLEAR(page);
+
+ // Update the free counts if the page was freed
+ if( !PAGE_ALLOC_TEST(page) )
+ {
+ 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));
+ }
+
+ #if TRACE_REF
+ Log("Page %P dereferenced (%i)", page << 12, MM_GetRefCount(page << 12));
+ #endif
+}
+
+int MM_GetRefCount( tPAddr PAddr )
+{
+ PAddr >>= 12;
+
+ if( PAddr > giMaxPhysPage ) return 0;
+
+ if( MM_GetPhysAddr( (tVAddr)&gaiPageReferences[PAddr] ) ) {
+ return gaiPageReferences[PAddr];
+ }
+
+ if( PAGE_ALLOC_TEST(PAddr) )
+ {
+ return 1;
+ }
+ return 0;
+}
+
+/**
+ * \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;
+}
+
+int MM_SetPageNode(tPAddr PAddr, void *Node)
+{
+ tPAddr page = PAddr >> 12;
+ tVAddr node_page = ((tVAddr)&gapPageNodes[page]) & ~(PAGE_SIZE-1);
+
+// if( !MM_GetRefCount(PAddr) ) return 1;
+
+ if( !MM_GetPhysAddr(node_page) ) {
+ if( !MM_Allocate(node_page) )
+ return -1;
+ memset( (void*)node_page, 0, PAGE_SIZE );
+ }
+
+ gapPageNodes[page] = Node;
+ return 0;
+}
+
+int MM_GetPageNode(tPAddr PAddr, void **Node)
+{
+// if( !MM_GetRefCount(PAddr) ) return 1;
+ PAddr >>= 12;
+
+ if( !MM_GetPhysAddr( (tVAddr)&gapPageNodes[PAddr] ) ) {
+ *Node = NULL;
+ return 0;
+ }
+
+ *Node = gapPageNodes[PAddr];
+ return 0;
+}
+
git.ucc.asn.au / tpg / acess2.git / blobdiff
UCC git Repository :: git.ucc.asn.au