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
189 && gaPageTable[Addr>>12] & PF_PRESENT
190 && gaPageTable[Addr>>12] & PF_COW )
193 if(MM_GetRefCount( gaPageTable[Addr>>12] & ~0xFFF ) == 1)
195 gaPageTable[Addr>>12] &= ~PF_COW;
196 gaPageTable[Addr>>12] |= PF_PRESENT|PF_WRITE;
200 //Log("MM_PageFault: COW - MM_DuplicatePage(0x%x)", Addr);
201 paddr = MM_DuplicatePage( Addr );
202 MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF );
203 gaPageTable[Addr>>12] &= PF_USER;
204 gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE;
207 INVLPG( Addr & ~0xFFF );
212 // If it was a user, tell the thread handler
214 Warning("%s %s %s memory%s",
215 (ErrorCode&4?"User":"Kernel"),
216 (ErrorCode&2?"write to":"read from"),
217 (ErrorCode&1?"bad/locked":"non-present"),
218 (ErrorCode&16?" (Instruction Fetch)":"")
220 Warning("User Pagefault: Instruction at %04x:%08x accessed %p", Regs->cs, Regs->eip, Addr);
221 __asm__ __volatile__ ("sti"); // Restart IRQs
223 Error_Backtrace(Regs->eip, Regs->ebp);
225 Threads_SegFault(Addr);
231 // -- Check Error Code --
233 Warning("Reserved Bits Trashed!");
236 Warning("%s %s %s memory%s",
237 (ErrorCode&4?"User":"Kernel"),
238 (ErrorCode&2?"write to":"read from"),
239 (ErrorCode&1?"bad/locked":"non-present"),
240 (ErrorCode&16?" (Instruction Fetch)":"")
244 Log("Code at %p accessed %p", Regs->eip, Addr);
245 // Print Stack Backtrace
246 Error_Backtrace(Regs->eip, Regs->ebp);
248 Log("gaPageDir[0x%x] = 0x%x", Addr>>22, gaPageDir[Addr>>22]);
249 if( gaPageDir[Addr>>22] & PF_PRESENT )
250 Log("gaPageTable[0x%x] = 0x%x", Addr>>12, gaPageTable[Addr>>12]);
252 //MM_DumpTables(0, -1);
255 Log("EAX %08x ECX %08x EDX %08x EBX %08x", Regs->eax, Regs->ecx, Regs->edx, Regs->ebx);
256 Log("ESP %08x EBP %08x ESI %08x EDI %08x", Regs->esp, Regs->ebp, Regs->esi, Regs->edi);
257 //Log("SS:ESP %04x:%08x", Regs->ss, Regs->esp);
258 Log("CS:EIP %04x:%08x", Regs->cs, Regs->eip);
259 Log("DS %04x ES %04x FS %04x GS %04x", Regs->ds, Regs->es, Regs->fs, Regs->gs);
262 __ASM__ ("mov %%dr0, %0":"=r"(dr0):);
263 __ASM__ ("mov %%dr1, %0":"=r"(dr1):);
264 Log("DR0 %08x DR1 %08x", dr0, dr1);
267 Panic("Page Fault at 0x%x (Accessed 0x%x)", Regs->eip, Addr);
271 * \fn void MM_DumpTables(tVAddr Start, tVAddr End)
272 * \brief Dumps the layout of the page tables
274 void MM_DumpTables(tVAddr Start, tVAddr End)
276 tVAddr rangeStart = 0;
280 const tPAddr MASK = ~0xF78;
282 Start >>= 12; End >>= 12;
285 Log("Directory Entries:");
286 for(page = Start >> 10;
287 page < (End >> 10)+1;
292 Log(" 0x%08x-0x%08x :: 0x%08x",
293 page<<22, ((page+1)<<22)-1,
294 gaPageDir[page]&~0xFFF
300 Log("Table Entries:");
301 for(page = Start, curPos = Start<<12;
303 curPos += 0x1000, page++)
305 if( !(gaPageDir[curPos>>22] & PF_PRESENT)
306 || !(gaPageTable[page] & PF_PRESENT)
307 || (gaPageTable[page] & MASK) != expected)
310 Log(" 0x%08x => 0x%08x - 0x%08x (%s%s%s%s%s)",
312 gaPageTable[rangeStart>>12] & ~0xFFF,
314 (expected & PF_NOPAGE ? "P" : "-"),
315 (expected & PF_COW ? "C" : "-"),
316 (expected & PF_GLOBAL ? "G" : "-"),
317 (expected & PF_USER ? "U" : "-"),
318 (expected & PF_WRITE ? "W" : "-"),
319 gaPageTable[page] & MASK, expected
323 if( !(gaPageDir[curPos>>22] & PF_PRESENT) ) continue;
324 if( !(gaPageTable[curPos>>12] & PF_PRESENT) ) continue;
326 expected = (gaPageTable[page] & MASK);
329 if(expected) expected += 0x1000;
333 Log("0x%08x => 0x%08x - 0x%08x (%s%s%s%s)",
335 gaPageTable[rangeStart>>12] & ~0xFFF,
337 (expected & PF_NOPAGE ? "p" : "-"),
338 (expected & PF_COW ? "C" : "-"),
339 (expected & PF_USER ? "U" : "-"),
340 (expected & PF_WRITE ? "W" : "-")
347 * \fn tPAddr MM_Allocate(tVAddr VAddr)
349 tPAddr MM_Allocate(tVAddr VAddr)
352 //ENTER("xVAddr", VAddr);
353 //__asm__ __volatile__ ("xchg %bx,%bx");
354 // Check if the directory is mapped
355 if( gaPageDir[ VAddr >> 22 ] == 0 )
357 // Allocate directory
358 paddr = MM_AllocPhys();
359 //LOG("paddr = 0x%llx (new table)", paddr);
361 Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
366 gaPageDir[ VAddr >> 22 ] = paddr | 3;
368 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
370 INVLPG( &gaPageDir[ VAddr >> 22 ] );
371 //LOG("Clearing new table");
372 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
374 // Check if the page is already allocated
375 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
376 Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
377 //LEAVE('X', gaPageTable[ VAddr >> 12 ] & ~0xFFF);
378 return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
382 paddr = MM_AllocPhys();
383 //LOG("paddr = 0x%llx", paddr);
385 Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)",
386 VAddr, __builtin_return_address(0));
391 gaPageTable[ VAddr >> 12 ] = paddr | 3;
393 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
394 // Invalidate Cache for address
395 INVLPG( VAddr & ~0xFFF );
402 * \fn void MM_Deallocate(tVAddr VAddr)
404 void MM_Deallocate(tVAddr VAddr)
406 if( gaPageDir[ VAddr >> 22 ] == 0 ) {
407 Warning("MM_Deallocate - Directory not mapped");
411 if(gaPageTable[ VAddr >> 12 ] == 0) {
412 Warning("MM_Deallocate - Page is not allocated");
417 MM_DerefPhys( gaPageTable[ VAddr >> 12 ] & ~0xFFF );
419 gaPageTable[ VAddr >> 12 ] = 0;
423 * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
424 * \brief Checks if the passed address is accesable
426 tPAddr MM_GetPhysAddr(tVAddr Addr)
428 if( !(gaPageDir[Addr >> 22] & 1) )
430 if( !(gaPageTable[Addr >> 12] & 1) )
432 return (gaPageTable[Addr >> 12] & ~0xFFF) | (Addr & 0xFFF);
436 * \fn void MM_SetCR3(Uint CR3)
437 * \brief Sets the current process space
439 void MM_SetCR3(Uint CR3)
441 __asm__ __volatile__ ("mov %0, %%cr3"::"r"(CR3));
445 * \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
446 * \brief Map a physical page to a virtual one
448 int MM_Map(tVAddr VAddr, tPAddr PAddr)
450 //ENTER("xVAddr xPAddr", VAddr, PAddr);
452 if( PAddr & 0xFFF || VAddr & 0xFFF ) {
453 Warning("MM_Map - Physical or Virtual Addresses are not aligned");
459 PAddr &= ~0xFFF; VAddr &= ~0xFFF;
461 // Check if the directory is mapped
462 if( gaPageDir[ VAddr >> 22 ] == 0 )
464 gaPageDir[ VAddr >> 22 ] = MM_AllocPhys() | 3;
467 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
469 INVLPG( &gaPageTable[ (VAddr >> 12) & ~0x3FF ] );
470 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
472 // Check if the page is already allocated
473 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
474 Warning("MM_Map - Allocating to used address");
480 gaPageTable[ VAddr >> 12 ] = PAddr | 3;
482 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
484 //LOG("gaPageTable[ 0x%x ] = (Uint)%p = 0x%x",
485 // VAddr >> 12, &gaPageTable[ VAddr >> 12 ], gaPageTable[ VAddr >> 12 ]);
490 //LOG("INVLPG( 0x%x )", VAddr);
498 * \fn tVAddr MM_ClearUser()
499 * \brief Clear user's address space
501 tVAddr MM_ClearUser(void)
506 for( i = 0; i < (MM_USER_MAX>>22); i ++ )
508 // Check if directory is not allocated
509 if( !(gaPageDir[i] & PF_PRESENT) ) {
515 for( j = 0; j < 1024; j ++ )
517 if( gaPageTable[i*1024+j] & 1 )
518 MM_DerefPhys( gaPageTable[i*1024+j] & ~0xFFF );
519 gaPageTable[i*1024+j] = 0;
522 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
524 INVLPG( &gaPageTable[i*1024] );
532 * \fn tPAddr MM_Clone(void)
533 * \brief Clone the current address space
535 tPAddr MM_Clone(void)
540 tVAddr kStackBase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
543 Mutex_Acquire( &glTempFractal );
545 // Create Directory Table
546 *gpTmpCR3 = MM_AllocPhys() | 3;
548 //LOG("Allocated Directory (%x)", *gpTmpCR3);
549 memsetd( gaTmpDir, 0, 1024 );
551 if( Threads_GetPID() != 0 )
554 for( i = 0; i < 768; i ++)
556 // Check if table is allocated
557 if( !(gaPageDir[i] & PF_PRESENT) ) {
563 // Allocate new table
564 gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
565 INVLPG( &gaTmpTable[page] );
567 for( j = 0; j < 1024; j ++, page++ )
569 if( !(gaPageTable[page] & PF_PRESENT) ) {
570 gaTmpTable[page] = 0;
575 MM_RefPhys( gaPageTable[page] & ~0xFFF );
577 if(gaPageTable[page] & PF_WRITE) {
578 gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
579 gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
580 INVLPG( page << 12 );
583 gaTmpTable[page] = gaPageTable[page];
588 // Map in kernel tables (and make fractal mapping)
589 for( i = 768; i < 1024; i ++ )
592 if( i == (PAGE_TABLE_ADDR >> 22) ) {
593 gaTmpDir[ PAGE_TABLE_ADDR >> 22 ] = *gpTmpCR3;
597 if( gaPageDir[i] == 0 ) {
602 //LOG("gaPageDir[%x/4] = 0x%x", i*4, gaPageDir[i]);
603 MM_RefPhys( gaPageDir[i] & ~0xFFF );
604 gaTmpDir[i] = gaPageDir[i];
607 // Allocate kernel stack
608 for(i = KERNEL_STACKS >> 22;
609 i < KERNEL_STACKS_END >> 22;
612 // Check if directory is allocated
613 if( (gaPageDir[i] & 1) == 0 ) {
618 // We don't care about other kernel stacks, just the current one
619 if( i != kStackBase >> 22 ) {
620 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
626 gaTmpDir[i] = MM_AllocPhys() | 3;
627 INVLPG( &gaTmpTable[i*1024] );
628 for( j = 0; j < 1024; j ++ )
630 // Is the page allocated? If not, skip
631 if( !(gaPageTable[i*1024+j] & 1) ) {
632 gaTmpTable[i*1024+j] = 0;
636 // We don't care about other kernel stacks
637 if( ((i*1024+j)*4096 & ~(KERNEL_STACK_SIZE-1)) != kStackBase ) {
638 gaTmpTable[i*1024+j] = 0;
643 gaTmpTable[i*1024+j] = MM_AllocPhys() | 3;
645 MM_RefPhys( gaTmpTable[i*1024+j] & ~0xFFF );
647 tmp = (void *) MM_MapTemp( gaTmpTable[i*1024+j] & ~0xFFF );
648 memcpy( tmp, (void *)( (i*1024+j)*0x1000 ), 0x1000 );
649 MM_FreeTemp( (Uint)tmp );
653 ret = *gpTmpCR3 & ~0xFFF;
654 Mutex_Release( &glTempFractal );
661 * \fn tVAddr MM_NewKStack(void)
662 * \brief Create a new kernel stack
664 tVAddr MM_NewKStack(void)
668 for(base = KERNEL_STACKS; base < KERNEL_STACKS_END; base += KERNEL_STACK_SIZE)
670 // Check if space is free
671 if(MM_GetPhysAddr(base) != 0) continue;
673 //for(i = KERNEL_STACK_SIZE; i -= 0x1000 ; )
674 for(i = 0; i < KERNEL_STACK_SIZE; i += 0x1000 )
676 if( MM_Allocate(base+i) == 0 )
678 // On error, print a warning and return error
679 Warning("MM_NewKStack - Out of memory");
681 //for( i += 0x1000 ; i < KERNEL_STACK_SIZE; i += 0x1000 )
682 // MM_Deallocate(base+i);
687 Log("MM_NewKStack - Allocated %p", base + KERNEL_STACK_SIZE);
688 return base+KERNEL_STACK_SIZE;
691 Warning("MM_NewKStack - No address space left");
696 * \fn tVAddr MM_NewWorkerStack()
697 * \brief Creates a new worker stack
699 tVAddr MM_NewWorkerStack()
706 tPAddr pages[WORKER_STACK_SIZE>>12];
708 // Get the old ESP and EBP
709 __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
710 __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
712 // TODO: Thread safety
713 // Find a free worker stack address
714 for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
717 if( gWorkerStacks[base/32] == -1 ) {
718 base += 31; base &= ~31;
719 base --; // Counteracted by the base++
723 if( gWorkerStacks[base/32] & (1 << base) ) {
728 if(base >= NUM_WORKER_STACKS) {
729 Warning("Uh-oh! Out of worker stacks");
734 gWorkerStacks[base/32] |= (1 << base);
735 // Make life easier for later calls
736 giLastUsedWorker = base;
738 base = WORKER_STACKS + base * WORKER_STACK_SIZE;
739 //Log(" MM_NewWorkerStack: base = 0x%x", base);
741 // Acquire the lock for the temp fractal mappings
742 Mutex_Acquire(&glTempFractal);
744 // Set the temp fractals to TID0's address space
745 *gpTmpCR3 = ((Uint)gaInitPageDir - KERNEL_BASE) | 3;
746 //Log(" MM_NewWorkerStack: *gpTmpCR3 = 0x%x", *gpTmpCR3);
750 // Check if the directory is mapped (we are assuming that the stacks
751 // will fit neatly in a directory)
752 //Log(" MM_NewWorkerStack: gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
753 if(gaTmpDir[ base >> 22 ] == 0) {
754 gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
755 INVLPG( &gaTmpTable[ (base>>12) & ~0x3FF ] );
759 for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
760 //for( addr = WORKER_STACK_SIZE; addr; addr -= 0x1000 )
762 pages[ addr >> 12 ] = MM_AllocPhys();
763 gaTmpTable[ (base + addr) >> 12 ] = pages[addr>>12] | 3;
766 // Release the temp mapping lock
767 Mutex_Release(&glTempFractal);
769 // Copy the old stack
770 oldstack = (esp + KERNEL_STACK_SIZE-1) & ~(KERNEL_STACK_SIZE-1);
771 esp = oldstack - esp; // ESP as an offset in the stack
773 // Make `base` be the top of the stack
774 base += WORKER_STACK_SIZE;
776 i = (WORKER_STACK_SIZE>>12) - 1;
777 // Copy the contents of the old stack to the new one, altering the addresses
778 // `addr` is refering to bytes from the stack base (mem downwards)
779 for(addr = 0; addr < esp; addr += 0x1000)
781 Uint *stack = (Uint*)( oldstack-(addr+0x1000) );
782 tmpPage = (void*)MM_MapTemp( pages[i] );
784 for(j = 0; j < 1024; j++)
786 // Possible Stack address?
787 if(oldstack-esp < stack[j] && stack[j] < oldstack)
788 tmpPage[j] = base - (oldstack - stack[j]);
789 else // Seems not, best leave it alone
790 tmpPage[j] = stack[j];
792 MM_FreeTemp((tVAddr)tmpPage);
796 //Log("MM_NewWorkerStack: RETURN 0x%x", base);
801 * \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
802 * \brief Sets the flags on a page
804 void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
807 if( !(gaPageDir[VAddr >> 22] & 1) ) return ;
808 if( !(gaPageTable[VAddr >> 12] & 1) ) return ;
810 ent = &gaPageTable[VAddr >> 12];
813 if( Mask & MM_PFLAG_RO )
815 if( Flags & MM_PFLAG_RO ) {
819 gaPageDir[VAddr >> 22] |= PF_WRITE;
825 if( Mask & MM_PFLAG_KERNEL )
827 if( Flags & MM_PFLAG_KERNEL ) {
831 gaPageDir[VAddr >> 22] |= PF_USER;
837 if( Mask & MM_PFLAG_COW )
839 if( Flags & MM_PFLAG_COW ) {
849 //Log("MM_SetFlags: *ent = 0x%08x, gaPageDir[%i] = 0x%08x",
850 // *ent, VAddr >> 22, gaPageDir[VAddr >> 22]);
854 * \brief Get the flags on a page
856 Uint MM_GetFlags(tVAddr VAddr)
862 if( !(gaPageDir[VAddr >> 22] & 1) ) return 0;
863 if( !(gaPageTable[VAddr >> 12] & 1) ) return 0;
865 ent = &gaPageTable[VAddr >> 12];
868 if( !(*ent & PF_WRITE) ) ret |= MM_PFLAG_RO;
870 if( !(*ent & PF_USER) ) ret |= MM_PFLAG_KERNEL;
872 if( *ent & PF_COW ) ret |= MM_PFLAG_COW;
878 * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
879 * \brief Duplicates a virtual page to a physical one
881 tPAddr MM_DuplicatePage(tVAddr VAddr)
887 //ENTER("xVAddr", VAddr);
890 if( !(gaPageDir [VAddr >> 22] & PF_PRESENT) ) return 0;
891 if( !(gaPageTable[VAddr >> 12] & PF_PRESENT) ) return 0;
897 ret = MM_AllocPhys();
899 // Write-lock the page (to keep data constistent), saving its R/W state
900 wasRO = (gaPageTable[VAddr >> 12] & PF_WRITE ? 0 : 1);
901 gaPageTable[VAddr >> 12] &= ~PF_WRITE;
905 temp = MM_MapTemp(ret);
906 memcpy( (void*)temp, (void*)VAddr, 0x1000 );
909 // Restore Writeable status
910 if(!wasRO) gaPageTable[VAddr >> 12] |= PF_WRITE;
918 * \fn Uint MM_MapTemp(tPAddr PAddr)
919 * \brief Create a temporary memory mapping
920 * \todo Show Luigi Barone (C Lecturer) and see what he thinks
922 tVAddr MM_MapTemp(tPAddr PAddr)
926 //ENTER("XPAddr", PAddr);
930 //LOG("glTempMappings = %i", glTempMappings);
934 Mutex_Acquire( &glTempMappings );
936 for( i = 0; i < NUM_TEMP_PAGES; i ++ )
938 // Check if page used
939 if(gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] & 1) continue;
941 gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] = PAddr | 3;
942 INVLPG( TEMP_MAP_ADDR + (i << 12) );
943 //LEAVE('p', TEMP_MAP_ADDR + (i << 12));
944 Mutex_Release( &glTempMappings );
945 return TEMP_MAP_ADDR + (i << 12);
947 Mutex_Release( &glTempMappings );
948 Threads_Yield(); // TODO: Use a sleep queue here instead
953 * \fn void MM_FreeTemp(tVAddr PAddr)
954 * \brief Free's a temp mapping
956 void MM_FreeTemp(tVAddr VAddr)
959 //ENTER("xVAddr", VAddr);
961 if(i >= (TEMP_MAP_ADDR >> 12))
962 gaPageTable[ i ] = 0;
968 * \fn tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
969 * \brief Allocates a contigous number of pages
971 tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
978 for( i = 0; i < NUM_HW_PAGES; i ++ )
980 // Check if addr used
981 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i ] & 1 )
984 // Check possible region
985 for( j = 0; j < Number && i + j < NUM_HW_PAGES; j ++ )
987 // If there is an allocated page in the region we are testing, break
988 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] & 1 ) break;
994 for( j = 0; j < Number; j++ ) {
995 MM_RefPhys( PAddr + (j<<12) );
996 gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] = (PAddr + (j<<12)) | 3;
998 return HW_MAP_ADDR + (i<<12);
1001 // If we don't find any, return NULL
1006 * \fn tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
1007 * \brief Allocates DMA physical memory
1008 * \param Pages Number of pages required
1009 * \param MaxBits Maximum number of bits the physical address can have
1010 * \param PhysAddr Pointer to the location to place the physical address allocated
1011 * \return Virtual address allocate
1013 tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
1015 tPAddr maxCheck = (1 << MaxBits);
1019 ENTER("iPages iMaxBits pPhysAddr", Pages, MaxBits, PhysAddr);
1022 if(MaxBits < 12 || !PhysAddr) {
1028 if(MaxBits >= PHYS_BITS) maxCheck = -1;
1031 if(Pages == 1 && MaxBits >= PHYS_BITS)
1033 phys = MM_AllocPhys();
1035 ret = MM_MapHWPages(phys, 1);
1046 phys = MM_AllocPhysRange(Pages, MaxBits);
1047 // - Was it allocated?
1053 // Allocated successfully, now map
1054 ret = MM_MapHWPages(phys, Pages);
1056 // If it didn't map, free then return 0
1057 for(;Pages--;phys+=0x1000)
1069 * \fn void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1070 * \brief Unmap a hardware page
1072 void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1076 //Log_Debug("VirtMem", "MM_UnmapHWPages: (VAddr=0x%08x, Number=%i)", VAddr, Number);
1079 if(VAddr < HW_MAP_ADDR || VAddr+Number*0x1000 > HW_MAP_MAX) return;
1083 Mutex_Acquire( &glTempMappings ); // Temp and HW share a directory, so they share a lock
1085 for( j = 0; j < Number; j++ )
1087 MM_DerefPhys( gaPageTable[ i + j ] & ~0xFFF );
1088 gaPageTable[ i + j ] = 0;
1091 Mutex_Release( &glTempMappings );
1095 EXPORT(MM_GetPhysAddr);
1098 EXPORT(MM_MapHWPages);
1099 EXPORT(MM_AllocDMA);
1100 EXPORT(MM_UnmapHWPages);