3 * - Physical memory manager
11 #define TRACE_ALLOCS 0 // Print trace messages on AllocPhys/DerefPhys
15 extern void gKernelEnd;
18 void MM_Install(tMBoot_Info *MBoot);
19 //tPAddr MM_AllocPhys(void);
20 //tPAddr MM_AllocPhysRange(int Pages, int MaxBits);
21 //void MM_RefPhys(tPAddr PAddr);
22 //void MM_DerefPhys(tPAddr PAddr);
23 // int MM_GetRefCount(tPAddr PAddr);
27 Uint64 giPhysAlloc = 0; // Number of allocated pages
28 Uint64 giPageCount = 0; // Total number of pages
29 Uint64 giLastPossibleFree = 0; // Last possible free page (before all pages are used)
31 Uint32 gaSuperBitmap[1024]; // Blocks of 1024 Pages
32 Uint32 gaPageBitmap[1024*1024/32]; // Individual pages
33 int *gaPageReferences;
34 #define REFENT_PER_PAGE (0x1000/sizeof(gaPageReferences[0]))
37 void MM_Install(tMBoot_Info *MBoot)
39 Uint kernelPages, num;
45 // --- Find largest address
46 MBoot->MMapAddr |= KERNEL_BASE;
47 ent = (void *)( MBoot->MMapAddr );
48 while( (Uint)ent < MBoot->MMapAddr + MBoot->MMapLength )
53 // If entry is RAM and is above `maxAddr`, change `maxAddr`
54 if(ent->Type == 1 && ent->Base + ent->Length > maxAddr)
55 maxAddr = ent->Base + ent->Length;
57 ent = (tMBoot_MMapEnt *)( (Uint)ent + ent->Size );
61 giPageCount = (MBoot->HighMem >> 2) + 256; // HighMem is a kByte value
64 giPageCount = maxAddr >> 12;
66 giLastPossibleFree = giPageCount - 1;
68 memsetd(gaPageBitmap, 0xFFFFFFFF, giPageCount/32);
70 // Set up allocateable space
71 ent = (void *)( MBoot->MMapAddr );
72 while( (Uint)ent < MBoot->MMapAddr + MBoot->MMapLength )
74 memsetd( &gaPageBitmap[ent->Base/(4096*32)], 0, ent->Length/(4096*32) );
75 ent = (tMBoot_MMapEnt *)( (Uint)ent + ent->Size );
78 // Get used page count (Kernel)
79 kernelPages = (Uint)&gKernelEnd - KERNEL_BASE - 0x100000;
80 kernelPages += 0xFFF; // Page Align
85 memsetd( &gaPageBitmap[0x100000/(4096*32)], -1, num );
86 gaPageBitmap[ 0x100000/(4096*32) + num ] = (1 << (kernelPages & 31)) - 1;
88 // Fill Superpage bitmap
89 num = kernelPages/(32*32);
90 memsetd( &gaSuperBitmap[0x100000/(4096*32*32)], -1, num );
91 gaSuperBitmap[ 0x100000/(4096*32*32) + num ] = (1 << ((kernelPages / 32) & 31)) - 1;
93 // Mark Multiboot's pages as taken
95 MM_RefPhys( (Uint)MBoot - KERNEL_BASE );
97 for(i = (MBoot->ModuleCount*sizeof(tMBoot_Module)+0xFFF)>12; i--; )
98 MM_RefPhys( MBoot->Modules + (i << 12) );
100 mods = (void*)(MBoot->Modules + KERNEL_BASE);
101 for(i = 0; i < MBoot->ModuleCount; i++)
103 num = (mods[i].End - mods[i].Start + 0xFFF) >> 12;
105 MM_RefPhys( (mods[i].Start & ~0xFFF) + (num<<12) );
108 gaPageReferences = (void*)MM_REFCOUNT_BASE;
110 Log_Log("PMem", "Physical memory set up");
114 * \fn tPAddr MM_AllocPhys(void)
115 * \brief Allocates a physical page from the general pool
117 tPAddr MM_AllocPhys(void)
125 Mutex_Acquire( &glPhysAlloc );
130 const int addrClasses[] = {0,16,20,24,32,64};
131 const int numAddrClasses = sizeof(addrClasses)/sizeof(addrClasses[0]);
134 for( i = numAddrClasses; i -- > 1; )
136 first = 1 << (addrClasses[i-1] - 12);
137 last = (1 << (addrClasses[i] - 12)) - 1;
138 // Range is above the last free page
139 if( first > giLastPossibleFree )
141 // Last possible free page is in the range
142 if( last > giLastPossibleFree )
143 last = giLastPossibleFree;
146 for( indx = first; indx < last; )
148 if( gaSuperBitmap[indx>>10] == -1 ) {
153 if( gaPageBitmap[indx>>5] == -1 ) {
158 if( gaPageBitmap[indx>>5] & (1 << (indx&31)) ) {
164 if( indx < last ) break;
166 giLastPossibleFree = first; // Well, we couldn't find any in this range
169 if( i <= 1 ) indx = -1;
174 LOG("giLastPossibleFree = %i", giLastPossibleFree);
175 for( indx = giLastPossibleFree; indx >= 0; )
177 if( gaSuperBitmap[indx>>10] == -1 ) {
182 if( gaPageBitmap[indx>>5] == -1 ) {
187 if( gaPageBitmap[indx>>5] & (1 << (indx&31)) ) {
194 giLastPossibleFree = indx;
195 LOG("indx = %i", indx);
197 c = giLastPossibleFree % 32;
198 b = (giLastPossibleFree / 32) % 32;
199 a = giLastPossibleFree / 1024;
201 LOG("a=%i,b=%i,c=%i", a, b, c);
202 for( ; gaSuperBitmap[a] == -1 && a >= 0; a-- );
204 Mutex_Release( &glPhysAlloc );
205 Warning("MM_AllocPhys - OUT OF MEMORY (Called by %p) - %lli/%lli used",
206 __builtin_return_address(0), giPhysAlloc, giPageCount);
210 for( ; gaSuperBitmap[a] & (1<<b); b-- );
211 for( ; gaPageBitmap[a*32+b] & (1<<c); c-- );
212 LOG("a=%i,b=%i,c=%i", a, b, c);
213 indx = (a << 10) | (b << 5) | c;
215 giLastPossibleFree = indx;
219 Mutex_Release( &glPhysAlloc );
220 Warning("MM_AllocPhys - OUT OF MEMORY (Called by %p) - %lli/%lli used (indx = %x)",
221 __builtin_return_address(0), giPhysAlloc, giPageCount, indx);
222 Log_Debug("PMem", "giLastPossibleFree = %lli", giLastPossibleFree);
227 if( indx > 0xFFFFF ) {
228 Panic("The fuck? Too many pages! (indx = 0x%x)", indx);
231 if( indx >= giPageCount ) {
232 Mutex_Release( &glPhysAlloc );
233 Log_Error("PMem", "MM_AllocPhys - indx(%i) > giPageCount(%i)", indx, giPageCount);
239 if( MM_GetPhysAddr( (tVAddr)&gaPageReferences[indx] ) )
240 gaPageReferences[indx] = 1;
241 gaPageBitmap[ indx>>5 ] |= 1 << (indx&31);
249 if(gaPageBitmap[ indx>>5 ] == -1) {
250 gaSuperBitmap[indx>>10] |= 1 << ((indx>>5)&31);
254 Mutex_Release( &glPhysAlloc );
258 Log_Debug("PMem", "MM_AllocPhys: RETURN 0x%llx (%i free)", ret, giPageCount-giPhysAlloc);
264 * \fn tPAddr MM_AllocPhysRange(int Pages, int MaxBits)
265 * \brief Allocate a range of physical pages
266 * \param Pages Number of pages to allocate
267 * \param MaxBits Maximum number of address bits to use
269 tPAddr MM_AllocPhysRange(int Pages, int MaxBits)
275 ENTER("iPages iMaxBits", Pages, MaxBits);
282 if(MaxBits > PHYS_BITS) MaxBits = PHYS_BITS;
285 Mutex_Acquire( &glPhysAlloc );
287 // Set up search state
288 if( giLastPossibleFree > ((tPAddr)1 << (MaxBits-12)) ) {
289 sidx = (tPAddr)1 << (MaxBits-12);
292 sidx = giLastPossibleFree;
300 LOG("a=%i, b=%i, idx=%i, sidx=%i", a, b, idx, sidx);
303 for( ; gaSuperBitmap[a] == -1 && a --; ) b = 31;
305 Mutex_Release( &glPhysAlloc );
306 Warning("MM_AllocPhysRange - OUT OF MEMORY (Called by %p)", __builtin_return_address(0));
311 for( ; gaSuperBitmap[a] & (1 << b); b-- ) sidx = 31;
314 for( ; gaPageBitmap[idx] & (1 << sidx); sidx-- )
315 LOG("gaPageBitmap[%i] = 0x%08x", idx, gaPageBitmap[idx]);
317 LOG("idx = %i, sidx = %i", idx, sidx);
322 // Check if the gap is large enough
329 if( gaPageBitmap[idx] == -1 ) {
335 if( gaPageBitmap[idx] & (1 << sidx) ) {
337 if(sidx < 0) { sidx = 31; idx --; }
345 // Check if it is a free range
346 for( i = 0; i < Pages; i++ )
349 if( gaPageBitmap[idx] & (1 << sidx) )
353 if(sidx < 0) { sidx = 31; idx --; }
361 // Check if an address was found
363 Mutex_Release( &glPhysAlloc );
364 Warning("MM_AllocPhysRange - OUT OF MEMORY (Called by %p)", __builtin_return_address(0));
370 for( i = 0; i < Pages; i++ )
372 if( MM_GetPhysAddr( (tVAddr)&gaPageReferences[idx*32+sidx] ) )
373 gaPageReferences[idx*32+sidx] = 1;
374 gaPageBitmap[ idx ] |= 1 << sidx;
377 if(sidx == 32) { sidx = 0; idx ++; }
381 ret = (idx << 17) | (sidx << 12);
384 if(gaPageBitmap[ idx ] == -1) gaSuperBitmap[idx/32] |= 1 << (idx%32);
387 Mutex_Release( &glPhysAlloc );
391 Log_Debug("PMem", "MM_AllocPhysRange: RETURN 0x%llx-0x%llx (%i free)",
392 ret, ret + (1<<Pages)-1, giPageCount-giPhysAlloc);
398 * \fn void MM_RefPhys(tPAddr PAddr)
400 void MM_RefPhys(tPAddr PAddr)
405 // We don't care about non-ram pages
406 if(PAddr >= giPageCount) return;
409 Mutex_Acquire( &glPhysAlloc );
411 // Reference the page
412 if( gaPageReferences )
414 if( MM_GetPhysAddr( (tVAddr)&gaPageReferences[PAddr] ) == 0 ) {
415 tVAddr addr = ((tVAddr)&gaPageReferences[PAddr]) & ~0xFFF;
416 Log_Debug("PMem", "MM_RefPhys: Info not allocated %llx", PAddr);
417 Mutex_Release( &glPhysAlloc );
418 if( MM_Allocate( addr ) == 0 ) {
419 Log_KernelPanic("PMem", "MM_RefPhys: Out of physical memory");
421 Mutex_Acquire( &glPhysAlloc );
422 memset( (void*)addr, 0, 0x1000 );
424 gaPageReferences[ PAddr ] ++;
428 gaPageBitmap[ PAddr / 32 ] |= 1 << (PAddr&31);
431 if(gaPageBitmap[ PAddr / 32 ] == -1)
432 gaSuperBitmap[PAddr/1024] |= 1 << ((PAddr/32)&31);
435 Mutex_Release( &glPhysAlloc );
439 * \fn void MM_DerefPhys(tPAddr PAddr)
440 * \brief Dereferences a physical page
442 void MM_DerefPhys(tPAddr PAddr)
447 // We don't care about non-ram pages
448 if(PAddr >= giPageCount) return;
450 // Check if it is freed
451 if( !(gaPageBitmap[PAddr / 32] & (1 << PAddr%32)) ) {
452 Log_Warning("MMVirt", "MM_DerefPhys - Non-referenced memory dereferenced");
457 Mutex_Acquire( &glPhysAlloc );
459 if( giLastPossibleFree < PAddr )
460 giLastPossibleFree = PAddr;
463 if( !MM_GetPhysAddr( (tVAddr)&gaPageReferences[PAddr] ) || (-- gaPageReferences[PAddr]) == 0 )
466 Log_Debug("PMem", "MM_DerefPhys: Free'd 0x%x (%i free)", PAddr, giPageCount-giPhysAlloc);
468 //LOG("Freed 0x%x by %p\n", PAddr<<12, __builtin_return_address(0));
470 gaPageBitmap[ PAddr / 32 ] &= ~(1 << (PAddr&31));
471 if(gaPageBitmap[ PAddr / 32 ] == 0)
472 gaSuperBitmap[ PAddr >> 10 ] &= ~(1 << ((PAddr >> 5)&31));
476 Mutex_Release( &glPhysAlloc );
480 * \fn int MM_GetRefCount(tPAddr Addr)
482 int MM_GetRefCount(tPAddr PAddr)
487 // We don't care about non-ram pages
488 if(PAddr >= giPageCount) return -1;
490 if( MM_GetPhysAddr( (tVAddr)&gaPageReferences[PAddr] ) == 0 )
491 return (gaPageBitmap[PAddr / 32] & (1 << PAddr%32)) ? 1 : 0;
493 // Check if it is freed
494 return gaPageReferences[ PAddr ];