2 * AcessOS Microkernel Version
10 * 0xFF - System Calls / Kernel's User Code
26 #define KERNEL_STACKS 0xF0000000
27 #define KERNEL_STACK_SIZE 0x00008000
28 #define KERNEL_STACKS_END 0xFC000000
29 #define WORKER_STACKS 0x00100000 // Thread0 Only!
30 #define WORKER_STACK_SIZE KERNEL_STACK_SIZE
31 #define WORKER_STACKS_END 0xB0000000
32 #define NUM_WORKER_STACKS ((WORKER_STACKS_END-WORKER_STACKS)/WORKER_STACK_SIZE)
34 #define PAE_PAGE_TABLE_ADDR 0xFC000000 // 16 MiB
35 #define PAE_PAGE_DIR_ADDR 0xFCFC0000 // 16 KiB
36 #define PAE_PAGE_PDPT_ADDR 0xFCFC3F00 // 32 bytes
37 #define PAE_TMP_PDPT_ADDR 0xFCFC3F20 // 32 bytes
38 #define PAE_TMP_DIR_ADDR 0xFCFE0000 // 16 KiB
39 #define PAE_TMP_TABLE_ADDR 0xFD000000 // 16 MiB
41 #define PAGE_TABLE_ADDR 0xFC000000
42 #define PAGE_DIR_ADDR 0xFC3F0000
43 #define PAGE_CR3_ADDR 0xFC3F0FC0
44 #define TMP_CR3_ADDR 0xFC3F0FC4 // Part of core instead of temp
45 #define TMP_DIR_ADDR 0xFC3F1000 // Same
46 #define TMP_TABLE_ADDR 0xFC400000
48 #define HW_MAP_ADDR 0xFE000000
49 #define HW_MAP_MAX 0xFFEF0000
50 #define NUM_HW_PAGES ((HW_MAP_MAX-HW_MAP_ADDR)/0x1000)
51 #define TEMP_MAP_ADDR 0xFFEF0000 // Allows 16 "temp" pages
52 #define NUM_TEMP_PAGES 16
53 #define LAST_BLOCK_ADDR 0xFFFF0000 // Free space for kernel provided user code/ *(-1) protection
55 #define PF_PRESENT 0x1
58 #define PF_GLOBAL 0x80
60 #define PF_NOPAGE 0x400
62 #define INVLPG(addr) __asm__ __volatile__ ("invlpg (%0)"::"r"(addr))
65 typedef Uint64 tTabEnt;
67 typedef Uint32 tTabEnt;
71 extern void _UsertextEnd, _UsertextBase;
72 extern Uint32 gaInitPageDir[1024];
73 extern Uint32 gaInitPageTable[1024];
74 extern void Threads_SegFault(tVAddr Addr);
75 extern void Error_Backtrace(Uint eip, Uint ebp);
78 void MM_PreinitVirtual(void);
79 void MM_InstallVirtual(void);
80 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
81 void MM_DumpTables(tVAddr Start, tVAddr End);
82 tVAddr MM_ClearUser(void);
83 tPAddr MM_DuplicatePage(tVAddr VAddr);
86 #define gaPageTable ((tTabEnt*)PAGE_TABLE_ADDR)
87 #define gaPageDir ((tTabEnt*)PAGE_DIR_ADDR)
88 #define gaTmpTable ((tTabEnt*)TMP_TABLE_ADDR)
89 #define gaTmpDir ((tTabEnt*)TMP_DIR_ADDR)
90 #define gpPageCR3 ((tTabEnt*)PAGE_CR3_ADDR)
91 #define gpTmpCR3 ((tTabEnt*)TMP_CR3_ADDR)
93 #define gaPAE_PageTable ((tTabEnt*)PAE_PAGE_TABLE_ADDR)
94 #define gaPAE_PageDir ((tTabEnt*)PAE_PAGE_DIR_ADDR)
95 #define gaPAE_MainPDPT ((tTabEnt*)PAE_PAGE_PDPT_ADDR)
96 #define gaPAE_TmpTable ((tTabEnt*)PAE_TMP_DIR_ADDR)
97 #define gaPAE_TmpDir ((tTabEnt*)PAE_TMP_DIR_ADDR)
98 #define gaPAE_TmpPDPT ((tTabEnt*)PAE_TMP_PDPT_ADDR)
100 tMutex glTempMappings;
101 tMutex glTempFractal;
102 Uint32 gWorkerStacks[(NUM_WORKER_STACKS+31)/32];
103 int giLastUsedWorker = 0;
107 * \fn void MM_PreinitVirtual(void)
108 * \brief Maps the fractal mappings
110 void MM_PreinitVirtual(void)
113 gaInitPageDir[ ((PAGE_TABLE_ADDR >> TAB)-3*512+3)*2 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
115 gaInitPageDir[ PAGE_TABLE_ADDR >> 22 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
117 INVLPG( PAGE_TABLE_ADDR );
121 * \fn void MM_InstallVirtual(void)
122 * \brief Sets up the constant page mappings
124 void MM_InstallVirtual(void)
129 // --- Pre-Allocate kernel tables
130 for( i = KERNEL_BASE >> TAB; i < 1024*4; i ++ )
132 if( gaPAE_PageDir[ i ] ) continue;
134 // Skip stack tables, they are process unique
135 if( i > KERNEL_STACKS >> TAB && i < KERNEL_STACKS_END >> TAB) {
136 gaPAE_PageDir[ i ] = 0;
140 gaPAE_PageDir[ i ] = MM_AllocPhys() | 3;
141 INVLPG( &gaPAE_PageTable[i*512] );
142 memset( &gaPAE_PageTable[i*512], 0, 0x1000 );
145 // --- Pre-Allocate kernel tables
146 for( i = KERNEL_BASE>>22; i < 1024; i ++ )
148 if( gaPageDir[ i ] ) continue;
149 // Skip stack tables, they are process unique
150 if( i > KERNEL_STACKS >> 22 && i < KERNEL_STACKS_END >> 22) {
155 gaPageDir[ i ] = MM_AllocPhys() | 3;
156 INVLPG( &gaPageTable[i*1024] );
157 memset( &gaPageTable[i*1024], 0, 0x1000 );
161 // Unset kernel on the User Text pages
162 for( i = ((tVAddr)&_UsertextEnd-(tVAddr)&_UsertextBase+0xFFF)/4096; i--; ) {
163 MM_SetFlags( (tVAddr)&_UsertextBase + i*4096, 0, MM_PFLAG_KERNEL );
168 * \brief Cleans up the SMP required mappings
170 void MM_FinishVirtualInit(void)
175 gaInitPageDir[ 0 ] = 0;
180 * \fn void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
181 * \brief Called on a page fault
183 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
185 //ENTER("xAddr bErrorCode", Addr, ErrorCode);
187 // -- Check for COW --
188 if( gaPageDir [Addr>>22] & PF_PRESENT && gaPageTable[Addr>>12] & PF_PRESENT
189 && gaPageTable[Addr>>12] & PF_COW )
192 if(MM_GetRefCount( gaPageTable[Addr>>12] & ~0xFFF ) == 1)
194 gaPageTable[Addr>>12] &= ~PF_COW;
195 gaPageTable[Addr>>12] |= PF_PRESENT|PF_WRITE;
199 //Log("MM_PageFault: COW - MM_DuplicatePage(0x%x)", Addr);
200 paddr = MM_DuplicatePage( Addr );
201 MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF );
202 gaPageTable[Addr>>12] &= PF_USER;
203 gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE;
206 INVLPG( Addr & ~0xFFF );
210 // If it was a user, tell the thread handler
212 Warning("%s %s %s memory%s",
213 (ErrorCode&4?"User":"Kernel"),
214 (ErrorCode&2?"write to":"read from"),
215 (ErrorCode&1?"bad/locked":"non-present"),
216 (ErrorCode&16?" (Instruction Fetch)":"")
218 Warning("User Pagefault: Instruction at %04x:%08x accessed %p", Regs->cs, Regs->eip, Addr);
219 __asm__ __volatile__ ("sti"); // Restart IRQs
221 Error_Backtrace(Regs->eip, Regs->ebp);
223 Threads_SegFault(Addr);
229 // -- Check Error Code --
231 Warning("Reserved Bits Trashed!");
234 Warning("%s %s %s memory%s",
235 (ErrorCode&4?"User":"Kernel"),
236 (ErrorCode&2?"write to":"read from"),
237 (ErrorCode&1?"bad/locked":"non-present"),
238 (ErrorCode&16?" (Instruction Fetch)":"")
242 Log("Code at %p accessed %p", Regs->eip, Addr);
243 // Print Stack Backtrace
244 Error_Backtrace(Regs->eip, Regs->ebp);
246 Log("gaPageDir[0x%x] = 0x%x", Addr>>22, gaPageDir[Addr>>22]);
247 if( gaPageDir[Addr>>22] & PF_PRESENT )
248 Log("gaPageTable[0x%x] = 0x%x", Addr>>12, gaPageTable[Addr>>12]);
250 //MM_DumpTables(0, -1);
253 Log("EAX %08x ECX %08x EDX %08x EBX %08x", Regs->eax, Regs->ecx, Regs->edx, Regs->ebx);
254 Log("ESP %08x EBP %08x ESI %08x EDI %08x", Regs->esp, Regs->ebp, Regs->esi, Regs->edi);
255 //Log("SS:ESP %04x:%08x", Regs->ss, Regs->esp);
256 Log("CS:EIP %04x:%08x", Regs->cs, Regs->eip);
257 Log("DS %04x ES %04x FS %04x GS %04x", Regs->ds, Regs->es, Regs->fs, Regs->gs);
260 __ASM__ ("mov %%dr0, %0":"=r"(dr0):);
261 __ASM__ ("mov %%dr1, %0":"=r"(dr1):);
262 Log("DR0 %08x DR1 %08x", dr0, dr1);
265 Panic("Page Fault at 0x%x (Accessed 0x%x)", Regs->eip, Addr);
269 * \fn void MM_DumpTables(tVAddr Start, tVAddr End)
270 * \brief Dumps the layout of the page tables
272 void MM_DumpTables(tVAddr Start, tVAddr End)
274 tVAddr rangeStart = 0;
278 const tPAddr MASK = ~0xF78;
280 Start >>= 12; End >>= 12;
283 Log("Directory Entries:");
284 for(page = Start >> 10;
285 page < (End >> 10)+1;
290 Log(" 0x%08x-0x%08x :: 0x%08x",
291 page<<22, ((page+1)<<22)-1,
292 gaPageDir[page]&~0xFFF
298 Log("Table Entries:");
299 for(page = Start, curPos = Start<<12;
301 curPos += 0x1000, page++)
303 if( !(gaPageDir[curPos>>22] & PF_PRESENT)
304 || !(gaPageTable[page] & PF_PRESENT)
305 || (gaPageTable[page] & MASK) != expected)
308 Log(" 0x%08x => 0x%08x - 0x%08x (%s%s%s%s%s)",
310 gaPageTable[rangeStart>>12] & ~0xFFF,
312 (expected & PF_NOPAGE ? "P" : "-"),
313 (expected & PF_COW ? "C" : "-"),
314 (expected & PF_GLOBAL ? "G" : "-"),
315 (expected & PF_USER ? "U" : "-"),
316 (expected & PF_WRITE ? "W" : "-"),
317 gaPageTable[page] & MASK, expected
321 if( !(gaPageDir[curPos>>22] & PF_PRESENT) ) continue;
322 if( !(gaPageTable[curPos>>12] & PF_PRESENT) ) continue;
324 expected = (gaPageTable[page] & MASK);
327 if(expected) expected += 0x1000;
331 Log("0x%08x => 0x%08x - 0x%08x (%s%s%s%s)",
333 gaPageTable[rangeStart>>12] & ~0xFFF,
335 (expected & PF_NOPAGE ? "p" : "-"),
336 (expected & PF_COW ? "C" : "-"),
337 (expected & PF_USER ? "U" : "-"),
338 (expected & PF_WRITE ? "W" : "-")
345 * \fn tPAddr MM_Allocate(tVAddr VAddr)
347 tPAddr MM_Allocate(tVAddr VAddr)
350 //ENTER("xVAddr", VAddr);
351 //__asm__ __volatile__ ("xchg %bx,%bx");
352 // Check if the directory is mapped
353 if( gaPageDir[ VAddr >> 22 ] == 0 )
355 // Allocate directory
356 paddr = MM_AllocPhys();
358 Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
362 // Map and mark as user (if needed)
363 gaPageDir[ VAddr >> 22 ] = paddr | 3;
364 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
366 INVLPG( &gaPageDir[ VAddr >> 22 ] );
367 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
369 // Check if the page is already allocated
370 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
371 Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
372 //LEAVE('X', gaPageTable[ VAddr >> 12 ] & ~0xFFF);
373 return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
377 paddr = MM_AllocPhys();
378 //LOG("paddr = 0x%llx", paddr);
380 Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)",
381 VAddr, __builtin_return_address(0));
386 gaPageTable[ VAddr >> 12 ] = paddr | 3;
388 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
389 // Invalidate Cache for address
390 INVLPG( VAddr & ~0xFFF );
397 * \fn void MM_Deallocate(tVAddr VAddr)
399 void MM_Deallocate(tVAddr VAddr)
401 if( gaPageDir[ VAddr >> 22 ] == 0 ) {
402 Warning("MM_Deallocate - Directory not mapped");
406 if(gaPageTable[ VAddr >> 12 ] == 0) {
407 Warning("MM_Deallocate - Page is not allocated");
412 MM_DerefPhys( gaPageTable[ VAddr >> 12 ] & ~0xFFF );
414 gaPageTable[ VAddr >> 12 ] = 0;
418 * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
419 * \brief Checks if the passed address is accesable
421 tPAddr MM_GetPhysAddr(tVAddr Addr)
423 if( !(gaPageDir[Addr >> 22] & 1) )
425 if( !(gaPageTable[Addr >> 12] & 1) )
427 return (gaPageTable[Addr >> 12] & ~0xFFF) | (Addr & 0xFFF);
431 * \fn void MM_SetCR3(Uint CR3)
432 * \brief Sets the current process space
434 void MM_SetCR3(Uint CR3)
436 __asm__ __volatile__ ("mov %0, %%cr3"::"r"(CR3));
440 * \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
441 * \brief Map a physical page to a virtual one
443 int MM_Map(tVAddr VAddr, tPAddr PAddr)
445 //ENTER("xVAddr xPAddr", VAddr, PAddr);
447 if( PAddr & 0xFFF || VAddr & 0xFFF ) {
448 Warning("MM_Map - Physical or Virtual Addresses are not aligned");
454 PAddr &= ~0xFFF; VAddr &= ~0xFFF;
456 // Check if the directory is mapped
457 if( gaPageDir[ VAddr >> 22 ] == 0 )
459 gaPageDir[ VAddr >> 22 ] = MM_AllocPhys() | 3;
462 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
464 INVLPG( &gaPageTable[ (VAddr >> 12) & ~0x3FF ] );
465 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
467 // Check if the page is already allocated
468 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
469 Warning("MM_Map - Allocating to used address");
475 gaPageTable[ VAddr >> 12 ] = PAddr | 3;
477 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
479 //LOG("gaPageTable[ 0x%x ] = (Uint)%p = 0x%x",
480 // VAddr >> 12, &gaPageTable[ VAddr >> 12 ], gaPageTable[ VAddr >> 12 ]);
485 //LOG("INVLPG( 0x%x )", VAddr);
493 * \fn tVAddr MM_ClearUser()
494 * \brief Clear user's address space
496 tVAddr MM_ClearUser(void)
500 for( i = 0; i < (MM_USER_MAX>>22); i ++ )
502 // Check if directory is not allocated
503 if( !(gaPageDir[i] & PF_PRESENT) ) {
509 for( j = 0; j < 1024; j ++ )
511 if( gaPageTable[i*1024+j] & 1 )
512 MM_DerefPhys( gaPageTable[i*1024+j] & ~0xFFF );
513 gaPageTable[i*1024+j] = 0;
516 // Deallocate directory
517 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
519 INVLPG( &gaPageTable[i*1024] );
527 * \fn tPAddr MM_Clone(void)
528 * \brief Clone the current address space
530 tPAddr MM_Clone(void)
535 tVAddr kStackBase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
538 Mutex_Acquire( &glTempFractal );
540 // Create Directory Table
541 *gpTmpCR3 = MM_AllocPhys() | 3;
543 //LOG("Allocated Directory (%x)", *gpTmpCR3);
544 memsetd( gaTmpDir, 0, 1024 );
546 if( Threads_GetPID() != 0 )
549 for( i = 0; i < 768; i ++)
551 // Check if table is allocated
552 if( !(gaPageDir[i] & PF_PRESENT) ) {
558 // Allocate new table
559 gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
560 INVLPG( &gaTmpTable[page] );
562 for( j = 0; j < 1024; j ++, page++ )
564 if( !(gaPageTable[page] & PF_PRESENT) ) {
565 gaTmpTable[page] = 0;
570 MM_RefPhys( gaPageTable[page] & ~0xFFF );
572 if(gaPageTable[page] & PF_WRITE) {
573 gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
574 gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
575 INVLPG( page << 12 );
578 gaTmpTable[page] = gaPageTable[page];
583 // Map in kernel tables (and make fractal mapping)
584 for( i = 768; i < 1024; i ++ )
587 if( i == (PAGE_TABLE_ADDR >> 22) ) {
588 gaTmpDir[ PAGE_TABLE_ADDR >> 22 ] = *gpTmpCR3;
592 if( gaPageDir[i] == 0 ) {
597 //LOG("gaPageDir[%x/4] = 0x%x", i*4, gaPageDir[i]);
598 MM_RefPhys( gaPageDir[i] & ~0xFFF );
599 gaTmpDir[i] = gaPageDir[i];
602 // Allocate kernel stack
603 for(i = KERNEL_STACKS >> 22;
604 i < KERNEL_STACKS_END >> 22;
607 // Check if directory is allocated
608 if( (gaPageDir[i] & 1) == 0 ) {
613 // We don't care about other kernel stacks, just the current one
614 if( i != kStackBase >> 22 ) {
615 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
621 gaTmpDir[i] = MM_AllocPhys() | 3;
622 INVLPG( &gaTmpTable[i*1024] );
623 for( j = 0; j < 1024; j ++ )
625 // Is the page allocated? If not, skip
626 if( !(gaPageTable[i*1024+j] & 1) ) {
627 gaTmpTable[i*1024+j] = 0;
631 // We don't care about other kernel stacks
632 if( ((i*1024+j)*4096 & ~(KERNEL_STACK_SIZE-1)) != kStackBase ) {
633 gaTmpTable[i*1024+j] = 0;
638 gaTmpTable[i*1024+j] = MM_AllocPhys() | 3;
640 MM_RefPhys( gaTmpTable[i*1024+j] & ~0xFFF );
642 tmp = (void *) MM_MapTemp( gaTmpTable[i*1024+j] & ~0xFFF );
643 memcpy( tmp, (void *)( (i*1024+j)*0x1000 ), 0x1000 );
644 MM_FreeTemp( (Uint)tmp );
648 ret = *gpTmpCR3 & ~0xFFF;
649 Mutex_Release( &glTempFractal );
656 * \fn tVAddr MM_NewKStack(void)
657 * \brief Create a new kernel stack
659 tVAddr MM_NewKStack(void)
663 for(base = KERNEL_STACKS; base < KERNEL_STACKS_END; base += KERNEL_STACK_SIZE)
665 // Check if space is free
666 if(MM_GetPhysAddr(base) != 0) continue;
668 //for(i = KERNEL_STACK_SIZE; i -= 0x1000 ; )
669 for(i = 0; i < KERNEL_STACK_SIZE; i += 0x1000 )
671 if( MM_Allocate(base+i) == 0 )
673 // On error, print a warning and return error
674 Warning("MM_NewKStack - Out of memory");
676 //for( i += 0x1000 ; i < KERNEL_STACK_SIZE; i += 0x1000 )
677 // MM_Deallocate(base+i);
682 Log("MM_NewKStack - Allocated %p", base + KERNEL_STACK_SIZE);
683 return base+KERNEL_STACK_SIZE;
686 Warning("MM_NewKStack - No address space left");
691 * \fn tVAddr MM_NewWorkerStack()
692 * \brief Creates a new worker stack
694 tVAddr MM_NewWorkerStack()
701 tPAddr pages[WORKER_STACK_SIZE>>12];
703 // Get the old ESP and EBP
704 __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
705 __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
707 // TODO: Thread safety
708 // Find a free worker stack address
709 for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
712 if( gWorkerStacks[base/32] == -1 ) {
713 base += 31; base &= ~31;
714 base --; // Counteracted by the base++
718 if( gWorkerStacks[base/32] & (1 << base) ) {
723 if(base >= NUM_WORKER_STACKS) {
724 Warning("Uh-oh! Out of worker stacks");
729 gWorkerStacks[base/32] |= (1 << base);
730 // Make life easier for later calls
731 giLastUsedWorker = base;
733 base = WORKER_STACKS + base * WORKER_STACK_SIZE;
734 //Log(" MM_NewWorkerStack: base = 0x%x", base);
736 // Acquire the lock for the temp fractal mappings
737 Mutex_Acquire(&glTempFractal);
739 // Set the temp fractals to TID0's address space
740 *gpTmpCR3 = ((Uint)gaInitPageDir - KERNEL_BASE) | 3;
741 //Log(" MM_NewWorkerStack: *gpTmpCR3 = 0x%x", *gpTmpCR3);
745 // Check if the directory is mapped (we are assuming that the stacks
746 // will fit neatly in a directory)
747 //Log(" MM_NewWorkerStack: gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
748 if(gaTmpDir[ base >> 22 ] == 0) {
749 gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
750 INVLPG( &gaTmpTable[ (base>>12) & ~0x3FF ] );
754 for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
755 //for( addr = WORKER_STACK_SIZE; addr; addr -= 0x1000 )
757 pages[ addr >> 12 ] = MM_AllocPhys();
758 gaTmpTable[ (base + addr) >> 12 ] = pages[addr>>12] | 3;
761 // Release the temp mapping lock
762 Mutex_Release(&glTempFractal);
764 // Copy the old stack
765 oldstack = (esp + KERNEL_STACK_SIZE-1) & ~(KERNEL_STACK_SIZE-1);
766 esp = oldstack - esp; // ESP as an offset in the stack
768 // Make `base` be the top of the stack
769 base += WORKER_STACK_SIZE;
771 i = (WORKER_STACK_SIZE>>12) - 1;
772 // Copy the contents of the old stack to the new one, altering the addresses
773 // `addr` is refering to bytes from the stack base (mem downwards)
774 for(addr = 0; addr < esp; addr += 0x1000)
776 Uint *stack = (Uint*)( oldstack-(addr+0x1000) );
777 tmpPage = (void*)MM_MapTemp( pages[i] );
779 for(j = 0; j < 1024; j++)
781 // Possible Stack address?
782 if(oldstack-esp < stack[j] && stack[j] < oldstack)
783 tmpPage[j] = base - (oldstack - stack[j]);
784 else // Seems not, best leave it alone
785 tmpPage[j] = stack[j];
787 MM_FreeTemp((tVAddr)tmpPage);
791 //Log("MM_NewWorkerStack: RETURN 0x%x", base);
796 * \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
797 * \brief Sets the flags on a page
799 void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
802 if( !(gaPageDir[VAddr >> 22] & 1) ) return ;
803 if( !(gaPageTable[VAddr >> 12] & 1) ) return ;
805 ent = &gaPageTable[VAddr >> 12];
808 if( Mask & MM_PFLAG_RO )
810 if( Flags & MM_PFLAG_RO ) {
814 gaPageDir[VAddr >> 22] |= PF_WRITE;
820 if( Mask & MM_PFLAG_KERNEL )
822 if( Flags & MM_PFLAG_KERNEL ) {
826 gaPageDir[VAddr >> 22] |= PF_USER;
832 if( Mask & MM_PFLAG_COW )
834 if( Flags & MM_PFLAG_COW ) {
844 //Log("MM_SetFlags: *ent = 0x%08x, gaPageDir[%i] = 0x%08x",
845 // *ent, VAddr >> 22, gaPageDir[VAddr >> 22]);
849 * \brief Get the flags on a page
851 Uint MM_GetFlags(tVAddr VAddr)
857 if( !(gaPageDir[VAddr >> 22] & 1) ) return 0;
858 if( !(gaPageTable[VAddr >> 12] & 1) ) return 0;
860 ent = &gaPageTable[VAddr >> 12];
863 if( !(*ent & PF_WRITE) ) ret |= MM_PFLAG_RO;
865 if( !(*ent & PF_USER) ) ret |= MM_PFLAG_KERNEL;
867 if( *ent & PF_COW ) ret |= MM_PFLAG_COW;
873 * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
874 * \brief Duplicates a virtual page to a physical one
876 tPAddr MM_DuplicatePage(tVAddr VAddr)
882 //ENTER("xVAddr", VAddr);
885 if( !(gaPageDir [VAddr >> 22] & PF_PRESENT) ) return 0;
886 if( !(gaPageTable[VAddr >> 12] & PF_PRESENT) ) return 0;
892 ret = MM_AllocPhys();
894 // Write-lock the page (to keep data constistent), saving its R/W state
895 wasRO = (gaPageTable[VAddr >> 12] & PF_WRITE ? 0 : 1);
896 gaPageTable[VAddr >> 12] &= ~PF_WRITE;
900 temp = MM_MapTemp(ret);
901 memcpy( (void*)temp, (void*)VAddr, 0x1000 );
904 // Restore Writeable status
905 if(!wasRO) gaPageTable[VAddr >> 12] |= PF_WRITE;
913 * \fn Uint MM_MapTemp(tPAddr PAddr)
914 * \brief Create a temporary memory mapping
915 * \todo Show Luigi Barone (C Lecturer) and see what he thinks
917 tVAddr MM_MapTemp(tPAddr PAddr)
921 //ENTER("XPAddr", PAddr);
925 //LOG("glTempMappings = %i", glTempMappings);
929 Mutex_Acquire( &glTempMappings );
931 for( i = 0; i < NUM_TEMP_PAGES; i ++ )
933 // Check if page used
934 if(gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] & 1) continue;
936 gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] = PAddr | 3;
937 INVLPG( TEMP_MAP_ADDR + (i << 12) );
938 //LEAVE('p', TEMP_MAP_ADDR + (i << 12));
939 Mutex_Release( &glTempMappings );
940 return TEMP_MAP_ADDR + (i << 12);
942 Mutex_Release( &glTempMappings );
943 Threads_Yield(); // TODO: Use a sleep queue here instead
948 * \fn void MM_FreeTemp(tVAddr PAddr)
949 * \brief Free's a temp mapping
951 void MM_FreeTemp(tVAddr VAddr)
954 //ENTER("xVAddr", VAddr);
956 if(i >= (TEMP_MAP_ADDR >> 12))
957 gaPageTable[ i ] = 0;
963 * \fn tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
964 * \brief Allocates a contigous number of pages
966 tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
973 for( i = 0; i < NUM_HW_PAGES; i ++ )
975 // Check if addr used
976 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i ] & 1 )
979 // Check possible region
980 for( j = 0; j < Number && i + j < NUM_HW_PAGES; j ++ )
982 // If there is an allocated page in the region we are testing, break
983 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] & 1 ) break;
989 for( j = 0; j < Number; j++ ) {
990 MM_RefPhys( PAddr + (j<<12) );
991 gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] = (PAddr + (j<<12)) | 3;
993 return HW_MAP_ADDR + (i<<12);
996 // If we don't find any, return NULL
1001 * \fn tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
1002 * \brief Allocates DMA physical memory
1003 * \param Pages Number of pages required
1004 * \param MaxBits Maximum number of bits the physical address can have
1005 * \param PhysAddr Pointer to the location to place the physical address allocated
1006 * \return Virtual address allocate
1008 tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
1010 tPAddr maxCheck = (1 << MaxBits);
1014 ENTER("iPages iMaxBits pPhysAddr", Pages, MaxBits, PhysAddr);
1017 if(MaxBits < 12 || !PhysAddr) {
1023 if(MaxBits >= PHYS_BITS) maxCheck = -1;
1026 if(Pages == 1 && MaxBits >= PHYS_BITS)
1028 phys = MM_AllocPhys();
1030 ret = MM_MapHWPages(phys, 1);
1041 phys = MM_AllocPhysRange(Pages, MaxBits);
1042 // - Was it allocated?
1048 // Allocated successfully, now map
1049 ret = MM_MapHWPages(phys, Pages);
1051 // If it didn't map, free then return 0
1052 for(;Pages--;phys+=0x1000)
1064 * \fn void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1065 * \brief Unmap a hardware page
1067 void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1071 //Log_Debug("VirtMem", "MM_UnmapHWPages: (VAddr=0x%08x, Number=%i)", VAddr, Number);
1074 if(VAddr < HW_MAP_ADDR || VAddr+Number*0x1000 > HW_MAP_MAX) return;
1078 Mutex_Acquire( &glTempMappings ); // Temp and HW share a directory, so they share a lock
1080 for( j = 0; j < Number; j++ )
1082 MM_DerefPhys( gaPageTable[ i + j ] & ~0xFFF );
1083 gaPageTable[ i + j ] = 0;
1086 Mutex_Release( &glTempMappings );
1090 EXPORT(MM_GetPhysAddr);
1093 EXPORT(MM_MapHWPages);
1094 EXPORT(MM_AllocDMA);
1095 EXPORT(MM_UnmapHWPages);