Kernel/arch/armv7/mm_virt.c

   1 /*
   2  * Acess2
   3  *
   4  * ARM7 Virtual Memory Manager
   5  * - arch/arm7/mm_virt.c
   6  */
   7 #define DEBUG   0
   8 #include <acess.h>
   9 #include <mm_virt.h>
  10 #include <hal_proc.h>
  11
  12 #define TRACE_MAPS      0
  13
  14 #define AP_KRW_ONLY     1       // Kernel page
  15 #define AP_KRO_ONLY     5       // Kernel RO page
  16 #define AP_RW_BOTH      3       // Standard RW
  17 #define AP_RO_BOTH      7       // COW Page
  18 #define AP_RO_USER      2       // User RO Page
  19 #define PADDR_MASK_LVL1 0xFFFFFC00
  20
  21 // === IMPORTS ===
  22 extern Uint32   kernel_table0[];
  23
  24 // === TYPES ===
  25 typedef struct
  26 {
  27         tPAddr  PhysAddr;
  28         Uint8   Size;
  29         Uint8   Domain;
  30         BOOL    bExecutable;
  31         BOOL    bGlobal;
  32         BOOL    bShared;
  33          int    AP;
  34 } tMM_PageInfo;
  35
  36 //#define FRACTAL(table1, addr) ((table1)[ (0xFF8/4*1024) + ((addr)>>20)])
  37 #define FRACTAL(table1, addr)   ((table1)[ (0xFF8/4*1024) + ((addr)>>22)])
  38 #define USRFRACTAL(addr)        (*((Uint32*)(0x7FDFF000) + ((addr)>>22)))
  39 #define TLBIALL()       __asm__ __volatile__ ("mcr p15, 0, %0, c8, c7, 0" : : "r" (0))
  40 #define TLBIMVA(addr)   __asm__ __volatile__ ("mcr p15, 0, %0, c8, c7, 1" : : "r" (addr))
  41
  42 // === PROTOTYPES ===
  43 void    MM_int_GetTables(tVAddr VAddr, Uint32 **Table0, Uint32 **Table1);
  44  int    MM_int_AllocateCoarse(tVAddr VAddr, int Domain);
  45  int    MM_int_SetPageInfo(tVAddr VAddr, tMM_PageInfo *pi);
  46  int    MM_int_GetPageInfo(tVAddr VAddr, tMM_PageInfo *pi);
  47 tVAddr  MM_NewUserStack(void);
  48 tPAddr  MM_AllocateZero(tVAddr VAddr);
  49 tPAddr  MM_AllocateRootTable(void);
  50 void    MM_int_CloneTable(Uint32 *DestEnt, int Table);
  51 tPAddr  MM_Clone(void);
  52 tVAddr  MM_NewKStack(int bGlobal);
  53 void    MM_int_DumpTableEnt(tVAddr Start, size_t Len, tMM_PageInfo *Info);
  54 //void  MM_DumpTables(tVAddr Start, tVAddr End);
  55 void    MM_PageFault(Uint32 PC, Uint32 Addr, Uint32 DFSR, int bPrefetch);
  56
  57 // === GLOBALS ===
  58 tPAddr  giMM_ZeroPage;
  59
  60 // === CODE ===
  61 int MM_InitialiseVirtual(void)
  62 {
  63         return 0;
  64 }
  65
  66 void MM_int_GetTables(tVAddr VAddr, Uint32 **Table0, Uint32 **Table1)
  67 {
  68         if(VAddr & 0x80000000) {
  69                 *Table0 = (void*)&kernel_table0;        // Level 0
  70                 *Table1 = (void*)MM_TABLE1KERN; // Level 1
  71         }
  72         else {
  73                 *Table0 = (void*)MM_TABLE0USER;
  74                 *Table1 = (void*)MM_TABLE1USER;
  75         }
  76 }
  77
  78 int MM_int_AllocateCoarse(tVAddr VAddr, int Domain)
  79 {
  80         Uint32  *table0, *table1;
  81         Uint32  *desc;
  82         tPAddr  paddr;
  83
  84         ENTER("xVAddr iDomain", VAddr, Domain);
  85
  86         MM_int_GetTables(VAddr, &table0, &table1);
  87
  88         VAddr &= ~(0x400000-1); // 4MiB per "block", 1 Page
  89
  90         desc = &table0[ VAddr>>20];
  91         LOG("desc = %p", desc);
  92
  93         // table0: 4 bytes = 1 MiB
  94
  95         LOG("desc[0] = %x", desc[0]);
  96         LOG("desc[1] = %x", desc[1]);
  97         LOG("desc[2] = %x", desc[2]);
  98         LOG("desc[3] = %x", desc[3]);
  99
 100         if( (desc[0] & 3) != 0 || (desc[1] & 3) != 0
 101          || (desc[2] & 3) != 0 || (desc[3] & 3) != 0 )
 102         {
 103                 // Error?
 104                 LEAVE('i', 1);
 105                 return 1;
 106         }
 107
 108         paddr = MM_AllocPhys();
 109         if( !paddr )
 110         {
 111                 // Error
 112                 LEAVE('i', 2);
 113                 return 2;
 114         }
 115
 116         *desc = paddr | (Domain << 5) | 1;
 117         desc[1] = desc[0] + 0x400;
 118         desc[2] = desc[0] + 0x800;
 119         desc[3] = desc[0] + 0xC00;
 120
 121         if( VAddr < 0x80000000 ) {
 122                 USRFRACTAL(VAddr) = paddr | 0x13;
 123         }
 124         else {
 125                 FRACTAL(table1, VAddr) = paddr | 0x13;
 126         }
 127
 128         // TLBIALL
 129         TLBIALL();
 130
 131         LEAVE('i', 0);
 132         return 0;
 133 }
 134
 135 int MM_int_SetPageInfo(tVAddr VAddr, tMM_PageInfo *pi)
 136 {
 137         Uint32  *table0, *table1;
 138         Uint32  *desc;
 139
 140         ENTER("pVAddr ppi", VAddr, pi);
 141
 142         MM_int_GetTables(VAddr, &table0, &table1);
 143
 144         desc = &table0[ VAddr >> 20 ];
 145         LOG("desc = %p", desc);
 146
 147         switch(pi->Size)
 148         {
 149         case 12:        // Small Page
 150         case 16:        // Large Page
 151                 LOG("Page");
 152                 if( (*desc & 3) == 0 ) {
 153                         MM_int_AllocateCoarse( VAddr, pi->Domain );
 154                 }
 155                 desc = &table1[ VAddr >> 12 ];
 156                 LOG("desc (2) = %p", desc);
 157                 if( pi->Size == 12 )
 158                 {
 159                         // Small page
 160                         // - Error if overwriting a large page
 161                         if( (*desc & 3) == 1 )  LEAVE_RET('i', 1);
 162                         if( pi->PhysAddr == 0 ) {
 163                                 *desc = 0;
 164                                 LEAVE('i', 0);
 165                                 return 0;
 166                         }
 167
 168                         *desc = (pi->PhysAddr & 0xFFFFF000) | 2;
 169                         if(!pi->bExecutable)    *desc |= 1;     // XN
 170                         if(!pi->bGlobal)        *desc |= 1 << 11;       // nG
 171                         if( pi->bShared)        *desc |= 1 << 10;       // S
 172                         *desc |= (pi->AP & 3) << 4;     // AP
 173                         *desc |= ((pi->AP >> 2) & 1) << 9;      // APX
 174                         TLBIMVA(VAddr & 0xFFFFF000);
 175                         LEAVE('i', 0);
 176                         return 0;
 177                 }
 178                 else
 179                 {
 180                         // Large page
 181                         Log_Warning("MMVirt", "TODO: Implement large pages in MM_int_SetPageInfo");
 182                 }
 183                 break;
 184         case 20:        // Section or unmapped
 185                 Log_Warning("MMVirt", "TODO: Implement sections in MM_int_SetPageInfo");
 186                 break;
 187         case 24:        // Supersection
 188                 // Error if not aligned
 189                 if( VAddr & 0xFFFFFF ) {
 190                         LEAVE('i', 1);
 191                         return 1;
 192                 }
 193                 if( (*desc & 3) == 0 || ((*desc & 3) == 2 && (*desc & (1 << 18)))  )
 194                 {
 195                         if( pi->PhysAddr == 0 ) {
 196                                 *desc = 0;
 197                         }
 198                         else {
 199                                 // Apply
 200                                 *desc = pi->PhysAddr & 0xFF000000;
 201 //                              *desc |= ((pi->PhysAddr >> 32) & 0xF) << 20;
 202 //                              *desc |= ((pi->PhysAddr >> 36) & 0x7) << 5;
 203                                 *desc |= 2 | (1 << 18);
 204                         }
 205                         // TODO: Apply to all entries
 206                         Log_Warning("MMVirt", "TODO: Apply changes to all entries of supersections");
 207                         LEAVE('i', 0);
 208                         return 0;
 209                 }
 210                 // TODO: What here?
 211                 Log_Warning("MMVirt", "TODO: 24-bit not on supersection?");
 212                 LEAVE('i', 1);
 213                 return 1;
 214         }
 215
 216         LEAVE('i', 1);
 217         return 1;
 218 }
 219
 220 int MM_int_GetPageInfo(tVAddr VAddr, tMM_PageInfo *pi)
 221 {
 222         Uint32  *table0, *table1;
 223         Uint32  desc;
 224
 225 //      LogF("MM_int_GetPageInfo: VAddr=%p, pi=%p\n", VAddr, pi);
 226
 227         MM_int_GetTables(VAddr, &table0, &table1);
 228
 229         desc = table0[ VAddr >> 20 ];
 230
 231 //      if( VAddr > 0x90000000)
 232 //              LOG("table0 desc(%p) = %x", &table0[ VAddr >> 20 ], desc);
 233
 234         pi->bExecutable = 1;
 235         pi->bGlobal = 0;
 236         pi->bShared = 0;
 237         pi->AP = 0;
 238
 239         switch( (desc & 3) )
 240         {
 241         // 0: Unmapped
 242         case 0:
 243                 pi->PhysAddr = 0;
 244                 pi->Size = 20;
 245                 pi->Domain = 0;
 246                 return 1;
 247
 248         // 1: Coarse page table
 249         case 1:
 250                 // Domain from top level table
 251                 pi->Domain = (desc >> 5) & 7;
 252                 // Get next level
 253                 desc = table1[ VAddr >> 12 ];
 254 //              LOG("table1 desc(%p) = %x", &table1[ VAddr >> 12 ], desc);
 255                 switch( desc & 3 )
 256                 {
 257                 // 0: Unmapped
 258                 case 0:
 259                         pi->Size = 12;
 260                         return 1;
 261                 // 1: Large Page (64KiB)
 262                 case 1:
 263                         pi->Size = 16;
 264                         pi->PhysAddr = desc & 0xFFFF0000;
 265                         pi->AP = ((desc >> 4) & 3) | (((desc >> 9) & 1) << 2);
 266                         pi->bExecutable = !(desc & 0x8000);
 267                         pi->bShared = (desc >> 10) & 1;
 268                         return 0;
 269                 // 2/3: Small page
 270                 case 2:
 271                 case 3:
 272                         pi->Size = 12;
 273                         pi->PhysAddr = desc & 0xFFFFF000;
 274                         pi->bExecutable = !(desc & 1);
 275                         pi->bGlobal = !(desc >> 11);
 276                         pi->bShared = (desc >> 10) & 1;
 277                         pi->AP = ((desc >> 4) & 3) | (((desc >> 9) & 1) << 2);
 278                         return 0;
 279                 }
 280                 return 1;
 281
 282         // 2: Section (or Supersection)
 283         case 2:
 284                 if( desc & (1 << 18) ) {
 285                         // Supersection
 286                         pi->PhysAddr = desc & 0xFF000000;
 287                         pi->PhysAddr |= (Uint64)((desc >> 20) & 0xF) << 32;
 288                         pi->PhysAddr |= (Uint64)((desc >> 5) & 0x7) << 36;
 289                         pi->Size = 24;
 290                         pi->Domain = 0; // Supersections default to zero
 291                         pi->AP = ((desc >> 10) & 3) | (((desc >> 15) & 1) << 2);
 292                         return 0;
 293                 }
 294
 295                 // Section
 296                 pi->PhysAddr = desc & 0xFFF80000;
 297                 pi->Size = 20;
 298                 pi->Domain = (desc >> 5) & 7;
 299                 pi->AP = ((desc >> 10) & 3) | (((desc >> 15) & 1) << 2);
 300                 return 0;
 301
 302         // 3: Reserved (invalid)
 303         case 3:
 304                 pi->PhysAddr = 0;
 305                 pi->Size = 20;
 306                 pi->Domain = 0;
 307                 return 2;
 308         }
 309         return 2;
 310 }
 311
 312 // --- Exports ---
 313 tPAddr MM_GetPhysAddr(tVAddr VAddr)
 314 {
 315         tMM_PageInfo    pi;
 316         if( MM_int_GetPageInfo(VAddr, &pi) )
 317                 return 0;
 318         return pi.PhysAddr | (VAddr & ((1 << pi.Size)-1));
 319 }
 320
 321 Uint MM_GetFlags(tVAddr VAddr)
 322 {
 323         tMM_PageInfo    pi;
 324          int    ret;
 325
 326         if( MM_int_GetPageInfo(VAddr, &pi) )
 327                 return 0;
 328
 329         ret = 0;
 330
 331         switch(pi.AP)
 332         {
 333         case 0:
 334                 break;
 335         case AP_KRW_ONLY:
 336                 ret |= MM_PFLAG_KERNEL;
 337                 break;
 338         case AP_KRO_ONLY:
 339                 ret |= MM_PFLAG_KERNEL|MM_PFLAG_RO;
 340                 break;
 341         case AP_RW_BOTH:
 342                 break;
 343         case AP_RO_BOTH:
 344                 ret |= MM_PFLAG_COW;
 345                 break;
 346         case AP_RO_USER:
 347                 ret |= MM_PFLAG_RO;
 348                 break;
 349         }
 350
 351         if( pi.bExecutable )    ret |= MM_PFLAG_EXEC;
 352         return ret;
 353 }
 354
 355 void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
 356 {
 357         tMM_PageInfo    pi;
 358         Uint    curFlags;
 359
 360         if( MM_int_GetPageInfo(VAddr, &pi) )
 361                 return ;
 362
 363         curFlags = MM_GetFlags(VAddr);
 364         if( (curFlags & Mask) == Flags )
 365                 return ;
 366         curFlags &= ~Mask;
 367         curFlags |= Flags;
 368
 369         if( curFlags & MM_PFLAG_COW )
 370                 pi.AP = AP_RO_BOTH;
 371         else
 372         {
 373                 switch(curFlags & (MM_PFLAG_KERNEL|MM_PFLAG_RO) )
 374                 {
 375                 case 0:
 376                         pi.AP = AP_RW_BOTH;     break;
 377                 case MM_PFLAG_KERNEL:
 378                         pi.AP = AP_KRW_ONLY;    break;
 379                 case MM_PFLAG_RO:
 380                         pi.AP = AP_RO_USER;     break;
 381                 case MM_PFLAG_KERNEL|MM_PFLAG_RO:
 382                         pi.AP = AP_KRO_ONLY;    break;
 383                 }
 384         }
 385
 386         pi.bExecutable = !!(curFlags & MM_PFLAG_EXEC);
 387
 388         MM_int_SetPageInfo(VAddr, &pi);
 389 }
 390
 391 int MM_Map(tVAddr VAddr, tPAddr PAddr)
 392 {
 393         tMM_PageInfo    pi = {0};
 394         #if TRACE_MAPS
 395         Log("MM_Map %P=>%p", PAddr, VAddr);
 396         #endif
 397
 398         pi.PhysAddr = PAddr;
 399         pi.Size = 12;
 400         if(VAddr < USER_STACK_TOP)
 401                 pi.AP = AP_RW_BOTH;
 402         else
 403                 pi.AP = AP_KRW_ONLY;    // Kernel Read/Write
 404         pi.bExecutable = 1;
 405         if( MM_int_SetPageInfo(VAddr, &pi) ) {
 406                 MM_DerefPhys(pi.PhysAddr);
 407                 return 0;
 408         }
 409         return pi.PhysAddr;
 410 }
 411
 412 tPAddr MM_Allocate(tVAddr VAddr)
 413 {
 414         tMM_PageInfo    pi = {0};
 415
 416         ENTER("pVAddr", VAddr);
 417
 418         pi.PhysAddr = MM_AllocPhys();
 419         if( pi.PhysAddr == 0 )  LEAVE_RET('i', 0);
 420         pi.Size = 12;
 421         if(VAddr < USER_STACK_TOP)
 422                 pi.AP = AP_RW_BOTH;
 423         else
 424                 pi.AP = AP_KRW_ONLY;
 425         pi.bExecutable = 0;
 426         if( MM_int_SetPageInfo(VAddr, &pi) ) {
 427                 MM_DerefPhys(pi.PhysAddr);
 428                 LEAVE('i', 0);
 429                 return 0;
 430         }
 431         LEAVE('x', pi.PhysAddr);
 432         return pi.PhysAddr;
 433 }
 434
 435 tPAddr MM_AllocateZero(tVAddr VAddr)
 436 {
 437         if( !giMM_ZeroPage ) {
 438                 giMM_ZeroPage = MM_Allocate(VAddr);
 439                 MM_RefPhys(giMM_ZeroPage);
 440                 memset((void*)VAddr, 0, PAGE_SIZE);
 441         }
 442         else {
 443                 MM_RefPhys(giMM_ZeroPage);
 444                 MM_Map(VAddr, giMM_ZeroPage);
 445         }
 446         MM_SetFlags(VAddr, MM_PFLAG_COW, MM_PFLAG_COW);
 447         return giMM_ZeroPage;
 448 }
 449
 450 void MM_Deallocate(tVAddr VAddr)
 451 {
 452         tMM_PageInfo    pi;
 453
 454         if( MM_int_GetPageInfo(VAddr, &pi) )    return ;
 455
 456         if( pi.PhysAddr == 0 )  return;
 457         MM_DerefPhys(pi.PhysAddr);
 458
 459         pi.PhysAddr = 0;
 460         pi.AP = 0;
 461         pi.bExecutable = 0;
 462         MM_int_SetPageInfo(VAddr, &pi);
 463 }
 464
 465 tPAddr MM_AllocateRootTable(void)
 466 {
 467         tPAddr  ret;
 468
 469         ret = MM_AllocPhysRange(2, -1);
 470         if( ret & 0x1000 ) {
 471                 MM_DerefPhys(ret);
 472                 MM_DerefPhys(ret+0x1000);
 473                 ret = MM_AllocPhysRange(3, -1);
 474                 if( ret & 0x1000 ) {
 475                         MM_DerefPhys(ret);
 476                         ret += 0x1000;
 477 //                      Log("MM_AllocateRootTable: Second try not aligned, %P", ret);
 478                 }
 479                 else {
 480                         MM_DerefPhys(ret + 0x2000);
 481 //                      Log("MM_AllocateRootTable: Second try aligned, %P", ret);
 482                 }
 483         }
 484 //      else
 485 //              Log("MM_AllocateRootTable: Got it in one, %P", ret);
 486         return ret;
 487 }
 488
 489 void MM_int_CloneTable(Uint32 *DestEnt, int Table)
 490 {
 491         tPAddr  table;
 492         Uint32  *tmp_map;
 493         Uint32  *cur = (void*)MM_TABLE1USER;
 494 //      Uint32  *cur = &FRACTAL(MM_TABLE1USER,0);
 495          int    i;
 496
 497         table = MM_AllocPhys();
 498         if(!table)      return ;
 499
 500         cur += 256*Table;
 501
 502         tmp_map = (void*)MM_MapTemp(table);
 503
 504         for( i = 0; i < 1024; i ++ )
 505         {
 506 //              Log_Debug("MMVirt", "cur[%i] (%p) = %x", Table*256+i, &cur[Table*256+i], cur[Table*256+i]);
 507                 switch(cur[i] & 3)
 508                 {
 509                 case 0: tmp_map[i] = 0; break;
 510                 case 1:
 511                         tmp_map[i] = 0;
 512                         Log_Error("MMVirt", "TODO: Support large pages in MM_int_CloneTable (%p)", (Table*256+i)*0x1000);
 513                         // Large page?
 514                         break;
 515                 case 2:
 516                 case 3:
 517                         // Small page
 518                         // - If full RW
 519 //                      Debug("%p cur[%i] & 0x230 = 0x%x", Table*256*0x1000, i, cur[i] & 0x230);
 520                         if( (cur[i] & 0x230) == 0x010 )
 521                         {
 522                                 void    *dst, *src;
 523                                 tPAddr  newpage;
 524                                 newpage = MM_AllocPhys();
 525                                 src = (void*)( (Table*256+i)*0x1000 );
 526                                 dst = (void*)MM_MapTemp(newpage);
 527 //                              Debug("Taking a copy of kernel page %p (%P)", src, cur[i] & ~0xFFF);
 528                                 memcpy(dst, src, PAGE_SIZE);
 529                                 MM_FreeTemp( (tVAddr)dst );
 530                                 tmp_map[i] = newpage | (cur[i] & 0xFFF);
 531                         }
 532                         else
 533                         {
 534                                 if( (cur[i] & 0x230) == 0x030 )
 535                                         cur[i] |= 0x200;        // Set to full RO (Full RO=COW, User RO = RO)
 536                                 tmp_map[i] = cur[i];
 537                                 MM_RefPhys( tmp_map[i] & ~0xFFF );
 538                         }
 539                         break;
 540                 }
 541         }
 542         MM_FreeTemp( (tVAddr) tmp_map );
 543
 544         DestEnt[0] = table + 0*0x400 + 1;
 545         DestEnt[1] = table + 1*0x400 + 1;
 546         DestEnt[2] = table + 2*0x400 + 1;
 547         DestEnt[3] = table + 3*0x400 + 1;
 548 }
 549
 550 tPAddr MM_Clone(void)
 551 {
 552         tPAddr  ret;
 553         Uint32  *new_lvl1_1, *new_lvl1_2, *cur;
 554         Uint32  *tmp_map;
 555          int    i;
 556
 557 //      MM_DumpTables(0, KERNEL_BASE);
 558
 559         ret = MM_AllocateRootTable();
 560
 561         cur = (void*)MM_TABLE0USER;
 562         new_lvl1_1 = (void*)MM_MapTemp(ret);
 563         new_lvl1_2 = (void*)MM_MapTemp(ret+0x1000);
 564         tmp_map = new_lvl1_1;
 565         for( i = 0; i < 0x800-4; i ++ )
 566         {
 567                 // HACK! Ignore the original identity mapping
 568                 if( i == 0 && Threads_GetTID() == 0 ) {
 569                         tmp_map[0] = 0;
 570                         continue;
 571                 }
 572                 if( i == 0x400 )
 573                         tmp_map = &new_lvl1_2[-0x400];
 574                 switch( cur[i] & 3 )
 575                 {
 576                 case 0: tmp_map[i] = 0; break;
 577                 case 1:
 578                         MM_int_CloneTable(&tmp_map[i], i);
 579                         i += 3; // Tables are alocated in blocks of 4
 580                         break;
 581                 case 2:
 582                 case 3:
 583                         Log_Error("MMVirt", "TODO: Support Sections/Supersections in MM_Clone (i=%i)", i);
 584                         tmp_map[i] = 0;
 585                         break;
 586                 }
 587         }
 588
 589         // Allocate Fractal table
 590         {
 591                  int    j, num;
 592                 tPAddr  tmp = MM_AllocPhys();
 593                 Uint32  *table = (void*)MM_MapTemp(tmp);
 594                 Uint32  sp;
 595                 register Uint32 __SP asm("sp");
 596
 597                 // Map table to last 4MiB of user space
 598                 new_lvl1_2[0x3FC] = tmp + 0*0x400 + 1;
 599                 new_lvl1_2[0x3FD] = tmp + 1*0x400 + 1;
 600                 new_lvl1_2[0x3FE] = tmp + 2*0x400 + 1;
 601                 new_lvl1_2[0x3FF] = tmp + 3*0x400 + 1;
 602
 603                 tmp_map = new_lvl1_1;
 604                 for( j = 0; j < 512; j ++ )
 605                 {
 606                         if( j == 256 )
 607                                 tmp_map = &new_lvl1_2[-0x400];
 608                         if( (tmp_map[j*4] & 3) == 1 )
 609                         {
 610                                 table[j] = tmp_map[j*4] & PADDR_MASK_LVL1;// 0xFFFFFC00;
 611                                 table[j] |= 0x813;      // nG, Kernel Only, Small page, XN
 612                         }
 613                         else
 614                                 table[j] = 0;
 615                 }
 616                 // Fractal
 617                 table[j++] = (ret + 0x0000) | 0x813;
 618                 table[j++] = (ret + 0x1000) | 0x813;
 619                 // Nuke the rest
 620                 for(      ; j < 1024; j ++ )
 621                         table[j] = 0;
 622
 623                 // Get kernel stack bottom
 624                 sp = __SP & ~(MM_KSTACK_SIZE-1);
 625                 j = (sp / 0x1000) % 1024;
 626                 num = MM_KSTACK_SIZE/0x1000;
 627
 628                 Log("num = %i, sp = %p, j = %i", num, sp, j);
 629
 630                 // Copy stack pages
 631                 for(; num--; j ++, sp += 0x1000)
 632                 {
 633                         tVAddr  page;
 634                         void    *tmp_page;
 635
 636                         page = MM_AllocPhys();
 637                         Log("page = %P", page);
 638                         table[j] = page | 0x813;
 639
 640                         tmp_page = (void*)MM_MapTemp(page);
 641                         memcpy(tmp_page, (void*)sp, 0x1000);
 642                         MM_FreeTemp( (tVAddr) tmp_page );
 643                 }
 644
 645                 MM_FreeTemp( (tVAddr)table );
 646         }
 647
 648         MM_FreeTemp( (tVAddr)new_lvl1_1 );
 649         MM_FreeTemp( (tVAddr)new_lvl1_2 );
 650
 651         return ret;
 652 }
 653
 654 void MM_ClearUser(void)
 655 {
 656          int    i, j;
 657         const int       user_table_count = USER_STACK_TOP / (256*0x1000);
 658         Uint32  *cur = (void*)MM_TABLE0USER;
 659         Uint32  *tab;
 660
 661 //      MM_DumpTables(0, 0x80000000);
 662
 663         Log("user_table_count = %i (as opposed to %i)", user_table_count, 0x800-4);
 664
 665         for( i = 0; i < user_table_count; i ++ )
 666         {
 667                 switch( cur[i] & 3 )
 668                 {
 669                 case 0: break;  // Already unmapped
 670                 case 1: // Sub pages
 671                         tab = (void*)(MM_TABLE1USER + i*256*sizeof(Uint32));
 672                         for( j = 0; j < 1024; j ++ )
 673                         {
 674                                 switch( tab[j] & 3 )
 675                                 {
 676                                 case 0: break;  // Unmapped
 677                                 case 1:
 678                                         Log_Error("MMVirt", "TODO: Support large pages in MM_ClearUser");
 679                                         break;
 680                                 case 2:
 681                                 case 3:
 682                                         MM_DerefPhys( tab[j] & ~(PAGE_SIZE-1) );
 683                                         break;
 684                                 }
 685                         }
 686                         MM_DerefPhys( cur[i] & ~(PAGE_SIZE-1) );
 687                         cur[i+0] = 0;
 688                         cur[i+1] = 0;
 689                         cur[i+2] = 0;
 690                         i += 3;
 691                         break;
 692                 case 2:
 693                 case 3:
 694                         Log_Error("MMVirt", "TODO: Implement sections/supersections in MM_ClearUser");
 695                         break;
 696                 }
 697                 cur[i] = 0;
 698         }
 699
 700         // Final block of 4 tables are KStack
 701         i = 0x800 - 4;
 702
 703         // Clear out unused stacks
 704         {
 705                 register Uint32 __SP asm("sp");
 706                  int    cur_stack_base = ((__SP & ~(MM_KSTACK_SIZE-1)) / PAGE_SIZE) % 1024;
 707
 708                 tab = (void*)(MM_TABLE1USER + i*256*sizeof(Uint32));
 709
 710                 // First 512 is the Table1 mapping + 2 for Table0 mapping
 711                 for( j = 512+2; j < 1024; j ++ )
 712                 {
 713                         // Skip current stack
 714                         if( j == cur_stack_base ) {
 715                                 j += (MM_KSTACK_SIZE / PAGE_SIZE) - 1;
 716                                 continue ;
 717                         }
 718                         if( !(tab[j] & 3) )     continue;
 719                         ASSERT( (tab[j] & 3) == 2 );
 720                         MM_DerefPhys( tab[j] & ~(PAGE_SIZE) );
 721                         tab[j] = 0;
 722                 }
 723         }
 724
 725
 726         MM_DumpTables(0, 0x80000000);
 727 //      Log_KernelPanic("MMVirt", "TODO: Implement MM_ClearUser");
 728 }
 729
 730 tVAddr MM_MapTemp(tPAddr PAddr)
 731 {
 732         tVAddr  ret;
 733         tMM_PageInfo    pi;
 734
 735         for( ret = MM_TMPMAP_BASE; ret < MM_TMPMAP_END - PAGE_SIZE; ret += PAGE_SIZE )
 736         {
 737                 if( MM_int_GetPageInfo(ret, &pi) == 0 )
 738                         continue;
 739
 740                 Log("MapTemp %P at %p by %p", PAddr, ret, __builtin_return_address(0));
 741                 MM_RefPhys(PAddr);      // Counter the MM_Deallocate in FreeTemp
 742                 MM_Map(ret, PAddr);
 743
 744                 return ret;
 745         }
 746         Log_Warning("MMVirt", "MM_MapTemp: All slots taken");
 747         return 0;
 748 }
 749
 750 void MM_FreeTemp(tVAddr VAddr)
 751 {
 752         if( VAddr < MM_TMPMAP_BASE || VAddr >= MM_TMPMAP_END ) {
 753                 Log_Warning("MMVirt", "MM_FreeTemp: Passed an addr not from MM_MapTemp (%p)", VAddr);
 754                 return ;
 755         }
 756
 757         MM_Deallocate(VAddr);
 758 }
 759
 760 tVAddr MM_MapHWPages(tPAddr PAddr, Uint NPages)
 761 {
 762         tVAddr  ret;
 763          int    i;
 764         tMM_PageInfo    pi;
 765
 766         ENTER("xPAddr iNPages", PAddr, NPages);
 767
 768         // Scan for a location
 769         for( ret = MM_HWMAP_BASE; ret < MM_HWMAP_END - NPages * PAGE_SIZE; ret += PAGE_SIZE )
 770         {
 771 //              LOG("checking %p", ret);
 772                 // Check if there is `NPages` free pages
 773                 for( i = 0; i < NPages; i ++ )
 774                 {
 775                         if( MM_int_GetPageInfo(ret + i*PAGE_SIZE, &pi) == 0 )
 776                                 break;
 777                 }
 778                 // Nope, jump to after the used page found and try again
 779 //              LOG("i = %i, ==? %i", i, NPages);
 780                 if( i != NPages ) {
 781                         ret += i * PAGE_SIZE;
 782                         continue ;
 783                 }
 784
 785                 // Map the pages
 786                 for( i = 0; i < NPages; i ++ )
 787                         MM_Map(ret+i*PAGE_SIZE, PAddr+i*PAGE_SIZE);
 788                 // and return
 789                 LEAVE('p', ret);
 790                 return ret;
 791         }
 792         Log_Warning("MMVirt", "MM_MapHWPages: No space for a %i page block", NPages);
 793         LEAVE('p', 0);
 794         return 0;
 795 }
 796
 797 tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PAddr)
 798 {
 799         tPAddr  phys;
 800         tVAddr  ret;
 801
 802         phys = MM_AllocPhysRange(Pages, MaxBits);
 803         if(!phys) {
 804                 Log_Warning("MMVirt", "No space left for a %i page block (MM_AllocDMA)", Pages);
 805                 return 0;
 806         }
 807
 808         ret = MM_MapHWPages(phys, Pages);
 809         *PAddr = phys;
 810
 811         return ret;
 812 }
 813
 814 void MM_UnmapHWPages(tVAddr Vaddr, Uint Number)
 815 {
 816         Log_Error("MMVirt", "TODO: Implement MM_UnmapHWPages");
 817 }
 818
 819 tVAddr MM_NewKStack(int bShared)
 820 {
 821         tVAddr  min_addr, max_addr;
 822         tVAddr  addr, ofs;
 823
 824         if( bShared ) {
 825                 min_addr = MM_GLOBALSTACKS;
 826                 max_addr = MM_GLOBALSTACKS_END;
 827         }
 828         else {
 829                 min_addr = MM_KSTACK_BASE;
 830                 max_addr = MM_KSTACK_END;
 831         }
 832
 833         // Locate a free slot
 834         for( addr = min_addr; addr < max_addr; addr += MM_KSTACK_SIZE )
 835         {
 836                 tMM_PageInfo    pi;
 837                 if( MM_int_GetPageInfo(addr+MM_KSTACK_SIZE-PAGE_SIZE, &pi) )    break;
 838         }
 839
 840         // Check for an error
 841         if(addr >= max_addr) {
 842                 return 0;
 843         }
 844
 845         // 1 guard page
 846         for( ofs = PAGE_SIZE; ofs < MM_KSTACK_SIZE; ofs += PAGE_SIZE )
 847         {
 848                 if( MM_Allocate(addr + ofs) == 0 )
 849                 {
 850                         while(ofs)
 851                         {
 852                                 ofs -= PAGE_SIZE;
 853                                 MM_Deallocate(addr + ofs);
 854                         }
 855                         Log_Warning("MMVirt", "MM_NewKStack: Unable to allocate");
 856                         return 0;
 857                 }
 858         }
 859         return addr + ofs;
 860 }
 861
 862 tVAddr MM_NewUserStack(void)
 863 {
 864         tVAddr  addr, ofs;
 865
 866         addr = USER_STACK_TOP - USER_STACK_SIZE;
 867         if( MM_GetPhysAddr(addr + PAGE_SIZE) ) {
 868                 Log_Error("MMVirt", "Unable to create initial user stack, addr %p taken",
 869                         addr + PAGE_SIZE
 870                         );
 871                 return 0;
 872         }
 873
 874         // 1 guard page
 875         for( ofs = PAGE_SIZE; ofs < USER_STACK_SIZE; ofs += PAGE_SIZE )
 876         {
 877                 tPAddr  rv;
 878                 if(ofs >= USER_STACK_SIZE - USER_STACK_COMM)
 879                         rv = MM_Allocate(addr + ofs);
 880                 else
 881                         rv = MM_AllocateZero(addr + ofs);
 882                 if(rv == 0)
 883                 {
 884                         while(ofs)
 885                         {
 886                                 ofs -= PAGE_SIZE;
 887                                 MM_Deallocate(addr + ofs);
 888                         }
 889                         Log_Warning("MMVirt", "MM_NewUserStack: Unable to allocate");
 890                         return 0;
 891                 }
 892                 MM_SetFlags(addr+ofs, 0, MM_PFLAG_KERNEL);
 893         }
 894 //      Log("Return %p", addr + ofs);
 895 //      MM_DumpTables(0, 0x80000000);
 896         return addr + ofs;
 897 }
 898
 899 void MM_int_DumpTableEnt(tVAddr Start, size_t Len, tMM_PageInfo *Info)
 900 {
 901         if( giMM_ZeroPage && Info->PhysAddr == giMM_ZeroPage )
 902         {
 903                 Debug("%p => %8s - 0x%7x %i %x",
 904                         Start, "ZERO", Len,
 905                         Info->Domain, Info->AP
 906                         );
 907         }
 908         else
 909         {
 910                 Debug("%p => %8x - 0x%7x %i %x",
 911                         Start, Info->PhysAddr-Len, Len,
 912                         Info->Domain, Info->AP
 913                         );
 914         }
 915 }
 916
 917 void MM_DumpTables(tVAddr Start, tVAddr End)
 918 {
 919         tVAddr  range_start = 0, addr;
 920         tMM_PageInfo    pi, pi_old;
 921          int    i = 0, inRange=0;
 922
 923         pi_old.Size = 0;
 924
 925         Debug("Page Table Dump:");
 926         range_start = Start;
 927         for( addr = Start; i == 0 || (addr && addr < End); i = 1 )
 928         {
 929                  int    rv;
 930 //              Log("addr = %p", addr);
 931                 rv = MM_int_GetPageInfo(addr, &pi);
 932                 if( rv
 933                  || pi.Size != pi_old.Size
 934                  || pi.Domain != pi_old.Domain
 935                  || pi.AP != pi_old.AP
 936                  || pi_old.PhysAddr != pi.PhysAddr )
 937                 {
 938                         if(inRange) {
 939                                 MM_int_DumpTableEnt(range_start, addr - range_start, &pi_old);
 940                         }
 941                         addr &= ~((1 << pi.Size)-1);
 942                         range_start = addr;
 943                 }
 944
 945                 pi_old = pi;
 946                 // Handle the zero page
 947                 if( !giMM_ZeroPage || pi_old.Size != 12 || pi_old.PhysAddr != giMM_ZeroPage )
 948                         pi_old.PhysAddr += 1 << pi_old.Size;
 949                 addr += 1 << pi_old.Size;
 950                 inRange = (rv == 0);
 951         }
 952         if(inRange)
 953                 MM_int_DumpTableEnt(range_start, addr - range_start, &pi);
 954         Debug("Done");
 955 }
 956
 957 // NOTE: Runs in abort context, not much differe, just a smaller stack
 958 void MM_PageFault(Uint32 PC, Uint32 Addr, Uint32 DFSR, int bPrefetch)
 959 {
 960          int    rv;
 961         tMM_PageInfo    pi;
 962
 963         rv = MM_int_GetPageInfo(Addr, &pi);
 964
 965         // Check for COW
 966         if( rv == 0 &&  pi.AP == AP_RO_BOTH )
 967         {
 968                 pi.AP = AP_RW_BOTH;
 969                 if( MM_GetRefCount(pi.PhysAddr) > 1 )
 970                 {
 971                         // Duplicate the page
 972                         tPAddr  newpage;
 973                         void    *dst, *src;
 974
 975                         newpage = MM_AllocPhys();
 976                         if(!newpage) {
 977                                 Log_Error("MMVirt", "Unable to allocate new page for COW");
 978                                 for(;;);
 979                         }
 980                         dst = (void*)MM_MapTemp(newpage);
 981                         src = (void*)(Addr & ~(PAGE_SIZE-1));
 982                         memcpy( dst, src, PAGE_SIZE );
 983                         MM_FreeTemp( (tVAddr)dst );
 984
 985                         Log_Notice("MMVirt", "COW %p caused by %p, %P duped to %P", Addr, PC,
 986                                 pi.PhysAddr, newpage);
 987
 988                         MM_DerefPhys(pi.PhysAddr);
 989                         pi.PhysAddr = newpage;
 990                 }
 991                 else {
 992                         Log_Notice("MMVirt", "COW %p caused by %p, took last reference to %P", Addr, PC, pi.PhysAddr);
 993                 }
 994                 // Unset COW
 995                 pi.AP = AP_RW_BOTH;
 996                 MM_int_SetPageInfo(Addr, &pi);
 997                 return ;
 998         }
 999
1000
1001         Log_Error("MMVirt", "Code at %p accessed %p (DFSR = 0x%x)%s", PC, Addr, DFSR,
1002                 (bPrefetch ? " - Prefetch" : "")
1003                 );
1004         for(;;);
1005 }
1006