KernelLand/Kernel/heap.c

   1 /*
   2  * Acess2 Kernel
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * heap.c
   6  * - Dynamic memory allocation
   7  */
   8 #include <acess.h>
   9 #include <mm_virt.h>
  10 #include <heap_int.h>
  11 #include <limits.h>
  12
  13 #define WARNINGS        1       // Warn and dump on heap errors
  14 #define DEBUG_TRACE     0       // Enable tracing of allocations
  15 #define VERBOSE_DUMP    0       // Set to 1 to enable a verbose dump when heap errors are encountered
  16
  17 // === CONSTANTS ===
  18 #define HEAP_INIT_SIZE  0x8000  // 32 KiB
  19 #define MIN_SIZE        (sizeof(void*))*8       // 8 Machine Words
  20 #define POW2_SIZES      0
  21 #define COMPACT_HEAP    0       // Use 4 byte header?
  22 #define FIRST_FIT       0
  23
  24 //#define       MAGIC_FOOT      0x2ACE5505
  25 //#define       MAGIC_FREE      0xACE55000
  26 //#define       MAGIC_USED      0x862B0505      // MAGIC_FOOT ^ MAGIC_FREE
  27 #define MAGIC_FOOT      0x544F4F46      // 'FOOT'
  28 #define MAGIC_FREE      0x45455246      // 'FREE'
  29 #define MAGIC_USED      0x44455355      // 'USED'
  30
  31 // === PROTOTYPES ===
  32 void    Heap_Install(void);
  33 void    *Heap_Extend(size_t Bytes);
  34 void    *Heap_Merge(tHeapHead *Head);
  35 //void  *Heap_Allocate(const char *File, int Line, size_t Bytes);
  36 //void  *Heap_AllocateZero(const char *File, int Line, size_t Bytes);
  37 //void  *Heap_Reallocate(const char *File, int Line, void *Ptr, size_t Bytes);
  38 //void  Heap_Deallocate(const char *File, int Line, void *Ptr);
  39 void    Heap_Dump(int bVerbose);
  40 void    Heap_Stats(void);
  41
  42 // === GLOBALS ===
  43 tMutex  glHeap;
  44 tHeapHead       *gHeapStart;
  45 tHeapHead       *gHeapEnd;
  46
  47 // === CODE ===
  48 void Heap_Install(void)
  49 {
  50         gHeapStart = (void*)MM_KHEAP_BASE;
  51         gHeapEnd   = gHeapStart;
  52         Heap_Extend(HEAP_INIT_SIZE);
  53 }
  54
  55 static inline tHeapHead *Heap_NextHead(tHeapHead *Head) {
  56         return (void*)( (char*)Head + Head->Size );
  57 }
  58 static inline tHeapFoot *Heap_ThisFoot(tHeapHead *Head) {
  59         return (void*)( (char*)Head + Head->Size - sizeof(tHeapFoot) );
  60 }
  61 static inline tHeapFoot *Heap_PrevFoot(tHeapHead *Head) {
  62         //ASSERT(Head != gHeapStart);
  63         return (void*)( (char*)Head - sizeof(tHeapFoot) );
  64 }
  65
  66 /**
  67  * \brief Extend the size of the heap
  68  */
  69 void *Heap_Extend(size_t Bytes)
  70 {
  71
  72         Debug("Heap_Extend(0x%x)", Bytes);
  73
  74         // Bounds Check
  75         if( gHeapEnd == (tHeapHead*)MM_KHEAP_MAX ) {
  76                 Log_Error("Heap", "Heap limit reached (%p)", (void*)MM_KHEAP_MAX);
  77                 return NULL;
  78         }
  79
  80         if( Bytes == 0 ) {
  81                 Log_Warning("Heap", "Heap_Extend called with Bytes=%i", Bytes);
  82                 return NULL;
  83         }
  84
  85         const Uint      pages = (Bytes + 0xFFF) >> 12;
  86         tHeapHead       *new_end = (void*)( (tVAddr)gHeapEnd + (pages << 12) );
  87         // Bounds Check
  88         if( new_end > (tHeapHead*)MM_KHEAP_MAX )
  89         {
  90                 Log_Error("Heap", "Heap limit exceeded (%p)", (void*)new_end);
  91                 // TODO: Clip allocation to avaliable space, and have caller check returned block
  92                 return NULL;
  93         }
  94
  95         // Heap expands in pages
  96         for( Uint i = 0; i < pages; i ++ )
  97         {
  98                 if( !MM_Allocate( (tVAddr)gHeapEnd+(i<<12) ) )
  99                 {
 100                         Warning("OOM - Heap_Extend (%i bytes)");
 101                         Heap_Dump(1);
 102                         return NULL;
 103                 }
 104         }
 105
 106         // Increase heap end
 107         tHeapHead       *head = gHeapEnd;
 108         gHeapEnd = new_end;
 109
 110         // Create Block
 111         head->Size = (Bytes+0xFFF)&~0xFFF;
 112         head->Magic = MAGIC_FREE;
 113         tHeapFoot *foot = Heap_ThisFoot(head);
 114         foot->Head = head;
 115         foot->Magic = MAGIC_FOOT;
 116
 117         return Heap_Merge(head);        // Merge with previous block
 118 }
 119
 120 /**
 121  * \brief Merges two ajacent heap blocks
 122  */
 123 void *Heap_Merge(tHeapHead *Head)
 124 {
 125         tHeapFoot       *foot;
 126         tHeapFoot       *thisFoot;
 127         tHeapHead       *head;
 128
 129         //Log("Heap_Merge: (Head=%p)", Head);
 130
 131         thisFoot = Heap_ThisFoot(Head);
 132         if( (void*)thisFoot > (void*)gHeapEnd )
 133                 return NULL;
 134
 135         // Merge Left (Down)
 136         foot = Heap_PrevFoot(Head);
 137         if( ((Uint)foot < (Uint)gHeapEnd && (Uint)foot > (Uint)gHeapStart)
 138         && foot->Head->Magic == MAGIC_FREE) {
 139                 foot->Head->Size += Head->Size; // Increase size
 140                 thisFoot->Head = foot->Head;    // Change backlink
 141                 Head->Magic = 0;        // Clear old head
 142                 Head->Size = 0;
 143                 Head = foot->Head;      // Save new head address
 144                 foot->Head = NULL;      // Clear central footer
 145                 foot->Magic = 0;
 146         }
 147
 148         // Merge Right (Upwards)
 149         head = Heap_NextHead(Head);
 150         if((Uint)head < (Uint)gHeapEnd && head->Magic == MAGIC_FREE)
 151         {
 152                 Head->Size += head->Size;
 153                 foot = Heap_ThisFoot(Head);
 154                 foot->Head = Head;      // Update Backlink
 155                 thisFoot->Head = NULL;  // Clear old footer
 156                 thisFoot->Magic = 0;
 157                 head->Size = 0;         // Clear old header
 158                 head->Magic = 0;
 159         }
 160
 161         // Return new address
 162         return Head;
 163 }
 164
 165 /**
 166  * \param File  Allocating source file
 167  * \param Line  Source line
 168  * \param __Bytes       Size of region to allocate
 169  */
 170 void *Heap_Allocate(const char *File, int Line, size_t __Bytes)
 171 {
 172         tHeapHead       *newhead;
 173         tHeapFoot       *foot, *newfoot;
 174         tHeapHead       *best = NULL;
 175         Uint    bestSize = UINT_MAX;    // Speed hack
 176         size_t  Bytes;
 177
 178         if( __Bytes == 0 ) {
 179                 return NULL;    // TODO: Return a known un-mapped range.
 180 //              return INVLPTR;
 181         }
 182
 183         // Get required size
 184         #if POW2_SIZES
 185         Bytes = __Bytes + sizeof(tHeapHead) + sizeof(tHeapFoot);
 186         Bytes = 1UUL << LOG2(__Bytes);
 187         #else
 188         Bytes = (__Bytes + sizeof(tHeapHead) + sizeof(tHeapFoot) + MIN_SIZE-1) & ~(MIN_SIZE-1);
 189         #endif
 190
 191         // Lock Heap
 192         Mutex_Acquire(&glHeap);
 193
 194         // Traverse Heap
 195         for( tHeapHead *head = gHeapStart; head < gHeapEnd; head = Heap_NextHead(head) )
 196         {
 197                 // Alignment Check
 198                 #if POW2_SIZES
 199                 if( head->Size != 1UUL << LOG2(head->Size) ) {
 200                 #else
 201                 if( head->Size & (MIN_SIZE-1) ) {
 202                 #endif
 203                         Mutex_Release(&glHeap); // Release spinlock
 204                         #if WARNINGS
 205                         Log_Warning("Heap", "Size of heap address %p is invalid"
 206                                 " - not aligned (0x%x) [at paddr 0x%x]",
 207                                 head, head->Size, MM_GetPhysAddr(&head->Size));
 208                         Heap_Dump(VERBOSE_DUMP);
 209                         #endif
 210                         return NULL;
 211                 }
 212                 if( head->Size < MIN_SIZE ) {
 213                         Mutex_Release(&glHeap);
 214                         Log_Warning("Heap", "Size of heap address %p is invalid"
 215                                 " - Too small (0x%x) [at paddr 0x%x]",
 216                                 head, head->Size, MM_GetPhysAddr(&head->Size));
 217                         Heap_Dump(VERBOSE_DUMP);
 218                         return NULL;
 219                 }
 220                 if( head->Size > (2<<30) ) {
 221                         Mutex_Release(&glHeap);
 222                         Log_Warning("Heap", "Size of heap address %p is invalid"
 223                                 " - Over 2GiB (0x%x) [at paddr 0x%x]",
 224                                 head, head->Size, MM_GetPhysAddr(&head->Size));
 225                         Heap_Dump(VERBOSE_DUMP);
 226                         return NULL;
 227                 }
 228
 229                 // Check if allocated
 230                 if(head->Magic == MAGIC_USED)   continue;
 231                 // Error check
 232                 if(head->Magic != MAGIC_FREE)   {
 233                         Mutex_Release(&glHeap); // Release spinlock
 234                         #if WARNINGS
 235                         Log_Warning("Heap", "Magic of heap address %p is invalid (%p = 0x%x)",
 236                                 head, &head->Magic, head->Magic);
 237                         Heap_Dump(VERBOSE_DUMP);
 238                         #endif
 239                         return NULL;
 240                 }
 241
 242                 // Size check
 243                 if(head->Size < Bytes)  continue;
 244
 245                 // Perfect fit
 246                 if(head->Size == Bytes) {
 247                         head->Magic = MAGIC_USED;
 248                         head->File = File;
 249                         head->Line = Line;
 250                         head->ValidSize = __Bytes;
 251                         head->AllocateTime = now();
 252                         Mutex_Release(&glHeap); // Release spinlock
 253                         #if DEBUG_TRACE
 254                         Log_Debug("Heap", "Malloc'd %p (0x%x bytes), returning to %s:%i",
 255                                 head->Data, head->Size, File, Line);
 256                         #endif
 257                         return head->Data;
 258                 }
 259
 260                 // Break out of loop
 261                 #if FIRST_FIT
 262                 best = head;
 263                 bestSize = head->Size;
 264                 break;
 265                 #else
 266                 // or check if the block is the best size
 267                 if(bestSize > head->Size) {
 268                         best = head;
 269                         bestSize = head->Size;
 270                 }
 271                 #endif
 272         }
 273
 274         // If no block large enough is found, create one
 275         if(!best)
 276         {
 277                 best = Heap_Extend( Bytes );
 278                 // Check for errors
 279                 if(!best) {
 280                         Warning("OOM when allocating 0x%x bytes", Bytes);
 281                         Mutex_Release(&glHeap); // Release spinlock
 282                         return NULL;
 283                 }
 284                 // Check size
 285                 if(best->Size == Bytes) {
 286                         best->Magic = MAGIC_USED;       // Mark block as used
 287                         best->File = File;
 288                         best->Line = Line;
 289                         best->ValidSize = __Bytes;
 290                         best->AllocateTime = now();
 291                         Mutex_Release(&glHeap); // Release spinlock
 292                         #if DEBUG_TRACE
 293                         Log_Debug("Heap", "Malloc'd %p (0x%x bytes), returning to %s:%i",
 294                                 best->Data, best->Size, File, Line);
 295                         #endif
 296                         return best->Data;
 297                 }
 298         }
 299
 300         // Split Block
 301         // - Save size for new block
 302         size_t  newsize = best->Size - Bytes;
 303         // - Allocate beginning of old block
 304         best->Size = Bytes;             // Update size in old header
 305         best->ValidSize = __Bytes;
 306         best->Magic = MAGIC_USED;       // Mark block as used
 307         best->File = File;
 308         best->Line = Line;
 309         best->AllocateTime = now();
 310         // - Create a new foot on old block
 311         newfoot = Heap_ThisFoot(best);
 312         newfoot->Head = best;   // Create new footer
 313         newfoot->Magic = MAGIC_FOOT;
 314         // - Create a new header after resized old
 315         newhead = Heap_NextHead(best);
 316         newhead->Size = newsize;
 317         newhead->Magic = MAGIC_FREE;
 318         newhead->ValidSize = 0;
 319         newhead->File = NULL;
 320         newhead->Line = 0;
 321         // - Update footer
 322         foot = Heap_ThisFoot(newhead);
 323         foot->Head = newhead;
 324
 325         Mutex_Release(&glHeap); // Release spinlock
 326         #if DEBUG_TRACE
 327         Log_Debug("Heap", "Malloc'd %p (0x%x bytes), returning to %s:%i",
 328                 best->Data, best->Size, File, Line);
 329         #endif
 330         return best->Data;
 331 }
 332
 333 /**
 334  * \brief Free an allocated memory block
 335  */
 336 void Heap_Deallocate(const char *File, int Line, void *Ptr)
 337 {
 338         // INVLPTR is returned from Heap_Allocate when the allocation
 339         // size is zero.
 340         if( Ptr == INVLPTR )    return;
 341
 342         // Alignment Check
 343         if( (tVAddr)Ptr % sizeof(void*) != 0 ) {
 344                 Log_Warning("Heap", "free - Passed a non-aligned address (%p)", Ptr);
 345                 return;
 346         }
 347
 348         // Sanity check
 349         if((Uint)Ptr < (Uint)gHeapStart || (Uint)Ptr > (Uint)gHeapEnd)
 350         {
 351                 Log_Warning("Heap", "free - Passed a non-heap address by %p (%p < %p < %p)",
 352                         __builtin_return_address(0), gHeapStart, Ptr, gHeapEnd);
 353                 return;
 354         }
 355
 356         // Check memory block - Header
 357         tHeapHead *head = (void*)( (Uint)Ptr - sizeof(tHeapHead) );
 358         if(head->Magic == MAGIC_FREE) {
 359                 Log_Warning("Heap", "free - Passed a freed block (%p) by %s:%i (was freed by %s:%i)",
 360                         head, File, Line,
 361                         head->File, head->Line);
 362                 return;
 363         }
 364         if(head->Magic != MAGIC_USED) {
 365                 Log_Warning("Heap", "free - Magic value is invalid (%p, 0x%x)", head, head->Magic);
 366                 Log_Notice("Heap", "Allocated by %s:%i", head->File, head->Line);
 367                 return;
 368         }
 369
 370         // Check memory block - Footer
 371         tHeapFoot *foot = Heap_ThisFoot(head);
 372         if(foot->Head != head) {
 373                 Log_Warning("Heap", "free - Footer backlink is incorrect (%p, 0x%x)", head, foot->Head);
 374                 Log_Notice("Heap", "Allocated by %s:%i", head->File, head->Line);
 375                 return;
 376         }
 377         if(foot->Magic != MAGIC_FOOT) {
 378                 Log_Warning("Heap", "free - Footer magic is invalid (%p, %p = 0x%x)",
 379                         head, &foot->Magic, foot->Magic);
 380                 Log_Notice("Heap", "Allocated by %s:%i", head->File, head->Line);
 381                 return;
 382         }
 383
 384         #if DEBUG_TRACE
 385         Log_Debug("Heap", "free: %p freed by %s:%i (%i old)",
 386                 Ptr, File, Line, now()-head->AllocateTime);
 387         #endif
 388
 389         // Lock
 390         Mutex_Acquire( &glHeap );
 391
 392         // Mark as free
 393         head->Magic = MAGIC_FREE;
 394         head->File = File;
 395         head->Line = Line;
 396         head->ValidSize = 0;
 397         // Merge blocks
 398         Heap_Merge( head );
 399
 400         // Release
 401         Mutex_Release( &glHeap );
 402 }
 403
 404 /**
 405  * \brief Increase/Decrease the size of an allocation
 406  * \param File  Calling File
 407  * \param Line  Calling Line
 408  * \param __ptr Old memory
 409  * \param __size        New Size
 410  */
 411 void *Heap_Reallocate(const char *File, int Line, void *__ptr, size_t __size)
 412 {
 413         tHeapHead       *head = (void*)( (Uint)__ptr-sizeof(tHeapHead) );
 414         tHeapHead       *nextHead;
 415         tHeapFoot       *foot;
 416         Uint    newSize = (__size + sizeof(tHeapFoot)+sizeof(tHeapHead)+MIN_SIZE-1)&~(MIN_SIZE-1);
 417
 418         // Check for reallocating NULL
 419         if(__ptr == NULL)       return Heap_Allocate(File, Line, __size);
 420
 421         // Check if resize is needed
 422         if(newSize <= head->Size)       return __ptr;
 423
 424         // Check if next block is free
 425         nextHead = Heap_NextHead(head);
 426
 427         // Extend into next block
 428         if(nextHead->Magic == MAGIC_FREE && nextHead->Size+head->Size >= newSize)
 429         {
 430                 Uint    size = nextHead->Size + head->Size;
 431                 foot = Heap_ThisFoot(nextHead);
 432                 // Exact Fit
 433                 if(size == newSize) {
 434                         head->Size = newSize;
 435                         head->ValidSize = __size;
 436                         head->File = File;
 437                         head->Line = Line;
 438                         foot->Head = head;
 439                         nextHead->Magic = 0;
 440                         nextHead->Size = 0;
 441                         return __ptr;
 442                 }
 443                 // Create a new heap block
 444                 // - Update old with new information
 445                 head->Size = newSize;
 446                 head->File = File;      // Kinda counts as a new allocation
 447                 head->Line = Line;
 448                 head->ValidSize = __size;
 449                 // - Create new footer
 450                 foot = Heap_ThisFoot(head);
 451                 foot->Head = head;
 452                 foot->Magic = MAGIC_FOOT;
 453                 // - Create new header
 454                 nextHead = Heap_NextHead(head);
 455                 nextHead->Size = size - newSize;
 456                 nextHead->Magic = MAGIC_FREE;
 457                 // - Update old footer
 458                 foot->Head = nextHead;
 459                 return __ptr;
 460         }
 461
 462         // Extend downwards?
 463         foot = Heap_PrevFoot(head);
 464         nextHead = foot->Head;
 465         if(nextHead->Magic == MAGIC_FREE && nextHead->Size+head->Size >= newSize)
 466         {
 467                 Uint    size = nextHead->Size + head->Size;
 468                 // Inexact fit, split things up
 469                 if(size > newSize)
 470                 {
 471                         // TODO: Handle splitting of downwards blocks
 472                         Warning("[Heap   ] TODO: Space efficient realloc when new size is smaller");
 473                 }
 474
 475                 // Exact fit
 476                 Uint    oldDataSize;
 477                 // Set 1st (new/lower) header
 478                 nextHead->Magic = MAGIC_USED;
 479                 nextHead->Size = newSize;
 480                 nextHead->File = File;
 481                 nextHead->Line = Line;
 482                 nextHead->ValidSize = __size;
 483                 // Get 2nd (old) footer
 484                 foot = Heap_ThisFoot(nextHead);
 485                 foot->Head = nextHead;
 486                 // Save old data size
 487                 oldDataSize = head->Size - sizeof(tHeapFoot) - sizeof(tHeapHead);
 488                 // Clear old header
 489                 head->Size = 0;
 490                 head->Magic = 0;
 491                 // Copy data
 492                 memmove(nextHead->Data, __ptr, oldDataSize);
 493                 // Return
 494                 return nextHead->Data;
 495         }
 496
 497         // Well, darn
 498         nextHead = Heap_Allocate( File, Line, __size );
 499         if(!nextHead)   return NULL;
 500         nextHead -= 1;
 501         nextHead->File = File;
 502         nextHead->Line = Line;
 503         nextHead->ValidSize = __size;
 504
 505         memcpy(
 506                 nextHead->Data,
 507                 __ptr,
 508                 head->Size - sizeof(tHeapFoot) - sizeof(tHeapHead)
 509                 );
 510
 511         free(__ptr);
 512
 513         return nextHead->Data;
 514 }
 515
 516 /**
 517  * \fn void *Heap_AllocateZero(const char *File, int Line, size_t Bytes)
 518  * \brief Allocate and Zero a buffer in memory
 519  * \param File  Allocating file
 520  * \param Line  Line of allocation
 521  * \param Bytes Size of the allocation
 522  */
 523 void *Heap_AllocateZero(const char *File, int Line, size_t Bytes)
 524 {
 525         void    *ret = Heap_Allocate(File, Line, Bytes);
 526         if(ret == NULL) return NULL;
 527
 528         memset( ret, 0, Bytes );
 529
 530         return ret;
 531 }
 532
 533 /**
 534  * \fn int Heap_IsHeapAddr(void *Ptr)
 535  * \brief Checks if an address is a heap pointer
 536  */
 537 int Heap_IsHeapAddr(void *Ptr)
 538 {
 539         tHeapHead       *head;
 540         if((Uint)Ptr < (Uint)gHeapStart)        return 0;
 541         if((Uint)Ptr > (Uint)gHeapEnd)  return 0;
 542         if((Uint)Ptr & (sizeof(Uint)-1))        return 0;
 543
 544         head = (void*)( (Uint)Ptr - sizeof(tHeapHead) );
 545         if(head->Magic != MAGIC_USED && head->Magic != MAGIC_FREE)
 546                 return 0;
 547
 548         return 1;
 549 }
 550
 551 /**
 552  */
 553 void Heap_Validate(void)
 554 {
 555         // Call dump non-verbosely.
 556         // - If a heap error is detected, it'll print
 557         Heap_Dump(0);
 558 }
 559
 560 void Heap_Dump(int bVerbose)
 561 {
 562         tHeapHead       *head, *badHead;
 563         tHeapFoot       *foot = NULL;
 564         static int      in_heap_dump;
 565
 566         if( in_heap_dump )      return;
 567
 568         in_heap_dump = 1;
 569
 570         head = gHeapStart;
 571         while( (Uint)head < (Uint)gHeapEnd )
 572         {
 573                 foot = Heap_ThisFoot(head);
 574
 575                 if( bVerbose )
 576                 {
 577                         Log_Log("Heap", "%p (%P): 0x%08x (%i) %4C",
 578                                 head, MM_GetPhysAddr(head), head->Size, head->ValidSize, &head->Magic);
 579                         Log_Log("Heap", "%p %4C", foot->Head, &foot->Magic);
 580                         if(head->File) {
 581                                 Log_Log("Heap", "%sowned by %s:%i",
 582                                         (head->Magic==MAGIC_FREE?"was ":""), head->File, head->Line);
 583                         }
 584                 }
 585
 586                 // Sanity Check Header
 587                 if(head->Size == 0) {
 588                         Log_Warning("Heap", "HALTED - Size is zero");
 589                         break;
 590                 }
 591                 if(head->Size & (MIN_SIZE-1)) {
 592                         Log_Warning("Heap", "HALTED - Size is malaligned");
 593                         break;
 594                 }
 595                 if(head->Magic != MAGIC_FREE && head->Magic != MAGIC_USED) {
 596                         Log_Warning("Heap", "HALTED - Head Magic is Bad");
 597                         break;
 598                 }
 599
 600                 // Check footer
 601                 if(foot->Magic != MAGIC_FOOT) {
 602                         Log_Warning("Heap", "HALTED - Foot Magic is Bad");
 603                         break;
 604                 }
 605                 if(head != foot->Head) {
 606                         Log_Warning("Heap", "HALTED - Footer backlink is invalid");
 607                         break;
 608                 }
 609
 610                 if( bVerbose )
 611                 {
 612                         Log_Log("Heap", "");
 613                 }
 614
 615                 // All OK? Go to next
 616                 head = foot->NextHead;
 617         }
 618
 619         // If the heap is valid, ok!
 620         if( (tVAddr)head == (tVAddr)gHeapEnd ) {
 621                 in_heap_dump = 0;
 622                 return ;
 623         }
 624
 625         // Check for a bad return
 626         if( (tVAddr)head >= (tVAddr)gHeapEnd ) {
 627                 in_heap_dump = 0;
 628                 return ;
 629         }
 630
 631         // If not verbose, we need to dump the failing block
 632         if( !bVerbose )
 633         {
 634                 Log_Log("Heap", "%p (%P): 0x%08lx %i %4C",
 635                         head, MM_GetPhysAddr(head), head->Size, head->ValidSize, &head->Magic);
 636                 if(foot)
 637                         Log_Log("Heap", "Foot %p = {Head:%p,Magic:%4C}", foot, foot->Head, &foot->Magic);
 638                 if(head->File) {
 639                         Log_Log("Heap", "%sowned by %s:%i",
 640                                 (head->Magic==MAGIC_FREE?"was ":""), head->File, head->Line);
 641                 }
 642                 Log_Log("Heap", "");
 643         }
 644
 645
 646         badHead = head;
 647
 648         // Work backwards
 649         foot = Heap_PrevFoot(gHeapEnd);
 650         Log_Log("Heap", "==== Going Backwards ==== (from %p)", foot);
 651         head = foot->Head;
 652         while( (tVAddr)head >= (tVAddr)badHead )
 653         {
 654                 Log_Log("Heap", "%p (%P): 0x%08lx %i %4C",
 655                         head, MM_GetPhysAddr(head), head->Size, head->ValidSize, &head->Magic);
 656                 Log_Log("Heap", "%p %4C", foot->Head, &foot->Magic);
 657                 if(head->File)
 658                         Log_Log("Heap", "%sowned by %s:%i",
 659                                 (head->Magic!=MAGIC_USED?"was ":""),
 660                                 head->File, head->Line);
 661                 Log_Log("Heap", "");
 662
 663                 // Sanity Check Header
 664                 if(head->Size == 0) {
 665                         Log_Warning("Heap", "HALTED - Size is zero");
 666                         break;
 667                 }
 668                 if(head->Size & (MIN_SIZE-1)) {
 669                         Log_Warning("Heap", " - Size is malaligned (&0x%x)", ~(MIN_SIZE-1));
 670                         break ;
 671                 }
 672                 if(head->Magic != MAGIC_FREE && head->Magic != MAGIC_USED) {
 673                         Log_Warning("Heap", "HALTED - Head Magic is Bad");
 674                         break;
 675                 }
 676
 677                 // Check footer
 678                 if(foot->Magic != MAGIC_FOOT) {
 679                         Log_Warning("Heap", "HALTED - Foot Magic is Bad");
 680                         break;
 681                 }
 682                 if(head != foot->Head) {
 683                         Log_Warning("Heap", "HALTED - Footer backlink is invalid");
 684                         break;
 685                 }
 686
 687                 if(head == badHead)     break;
 688
 689                 foot = Heap_PrevFoot(head);
 690                 head = foot->Head;
 691                 Log_Debug("Heap", "head=%p", head);
 692         }
 693
 694         Panic("Heap_Dump - Heap is corrupted, kernel panic!");
 695 }
 696
 697 void Heap_Stats(void)
 698 {
 699          int    nBlocks = 0;
 700          int    nFree = 0;
 701          int    totalBytes = 0;
 702          int    freeBytes = 0;
 703          int    maxAlloc=0, minAlloc=-1;
 704          int    avgAlloc, frag, overhead;
 705
 706         for( tHeapHead *head = gHeapStart; head < gHeapEnd; head = Heap_NextHead(head) )
 707         {
 708                 nBlocks ++;
 709                 totalBytes += head->Size;
 710                 if( head->Magic == MAGIC_FREE )
 711                 {
 712                         nFree ++;
 713                         freeBytes += head->Size;
 714                 }
 715                 else if( head->Magic == MAGIC_USED) {
 716                         if(maxAlloc < head->Size)       maxAlloc = head->Size;
 717                         if(minAlloc == -1 || minAlloc > head->Size)
 718                                 minAlloc = head->Size;
 719                 }
 720                 else {
 721                         Log_Warning("Heap", "Magic on %p invalid, skipping remainder of heap", head);
 722                         break;
 723                 }
 724
 725                 // Print the block info?
 726                 #if 1
 727                 if( head->Magic == MAGIC_FREE )
 728                         Log_Debug("Heap", "%p (%P) - 0x%x free",
 729                                 head->Data, MM_GetPhysAddr(&head->Data), head->Size);
 730                 else
 731                         Log_Debug("Heap", "%p (%P) - 0x%x (%i) Owned by %s:%i (%lli ms old)",
 732                                 head->Data, MM_GetPhysAddr(&head->Data), head->Size,
 733                                 head->ValidSize, head->File, head->Line,
 734                                 now() - head->AllocateTime
 735                                 );
 736                 #endif
 737         }
 738
 739         Log_Log("Heap", "%i blocks (0x%x bytes)", nBlocks, totalBytes);
 740         Log_Log("Heap", "%i free blocks (0x%x bytes)", nFree, freeBytes);
 741         if(nBlocks != 0)
 742                 frag = (nFree-1)*10000/nBlocks;
 743         else
 744                 frag = 0;
 745         Log_Log("Heap", "%i.%02i%% Heap Fragmentation", frag/100, frag%100);
 746         if(nBlocks <= nFree)
 747                 avgAlloc = 0;
 748         else
 749                 avgAlloc = (totalBytes-freeBytes)/(nBlocks-nFree);
 750         if(avgAlloc != 0)
 751                 overhead = (sizeof(tHeapFoot)+sizeof(tHeapHead))*10000/avgAlloc;
 752         else
 753                 overhead = 0;
 754         Log_Log("Heap", "Average allocation: %i bytes, Average Overhead: %i.%02i%%",
 755                 avgAlloc, overhead/100, overhead%100
 756                 );
 757         Log_Log("Heap", "Smallest Block: %i bytes, Largest: %i bytes",
 758                 minAlloc, maxAlloc);
 759
 760         // Scan and get distribution
 761         #if 1
 762         if(nBlocks > 0)
 763         {
 764                 struct {
 765                         Uint    Size;
 766                         Uint    Count;
 767                 }       sizeCounts[nBlocks];
 768                  int    i;
 769
 770                 memset(sizeCounts, 0, nBlocks*sizeof(sizeCounts[0]));
 771
 772                 for(tHeapHead *head = gHeapStart; head < gHeapEnd; head = (void*)( (tVAddr)head + head->Size ) )
 773                 {
 774                         for( i = 0; i < nBlocks; i ++ ) {
 775                                 if( sizeCounts[i].Size == 0 )
 776                                         break;
 777                                 if( sizeCounts[i].Size == head->Size )
 778                                         break;
 779                         }
 780                         // Should never reach this part (in a non-concurrent case)
 781                         if( i == nBlocks )      continue;
 782                         sizeCounts[i].Size = head->Size;
 783                         sizeCounts[i].Count ++;
 784                         #if 0
 785                         Log("Heap_Stats: %i %p - 0x%x bytes (%s) (%i)", nBlocks, head,
 786                                 head->Size, (head->Magic==MAGIC_FREE?"FREE":"used"), i
 787                                 );
 788                         Log("Heap_Stats: sizeCounts[%i] = {Size:0x%x, Count: %i}", i,
 789                                 sizeCounts[i].Size, sizeCounts[i].Count);
 790                         #endif
 791                 }
 792
 793                 for( i = 0; i < nBlocks && sizeCounts[i].Count; i ++ )
 794                 {
 795                         Log("Heap_Stats: 0x%x - %i blocks",
 796                                 sizeCounts[i].Size, sizeCounts[i].Count
 797                                 );
 798                 }
 799         }
 800         #endif
 801 }
 802
 803 // === EXPORTS ===
 804 EXPORT(Heap_Allocate);
 805 EXPORT(Heap_AllocateZero);
 806 EXPORT(Heap_Reallocate);
 807 EXPORT(Heap_Deallocate);
 808 EXPORT(Heap_IsHeapAddr);