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
59 #define PF_PAGED 0x400
61 #define INVLPG(addr) __asm__ __volatile__ ("invlpg (%0)"::"r"(addr))
64 typedef Uint64 tTabEnt;
66 typedef Uint32 tTabEnt;
70 extern void _UsertextEnd, _UsertextBase;
71 extern Uint32 gaInitPageDir[1024];
72 extern Uint32 gaInitPageTable[1024];
73 extern void Threads_SegFault(tVAddr Addr);
74 extern void Error_Backtrace(Uint eip, Uint ebp);
77 void MM_PreinitVirtual();
78 void MM_InstallVirtual();
79 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
80 void MM_DumpTables(tVAddr Start, tVAddr End);
81 tPAddr MM_DuplicatePage(tVAddr VAddr);
84 #define gaPageTable ((tTabEnt*)PAGE_TABLE_ADDR)
85 #define gaPageDir ((tTabEnt*)PAGE_DIR_ADDR)
86 #define gaTmpTable ((tTabEnt*)TMP_TABLE_ADDR)
87 #define gaTmpDir ((tTabEnt*)TMP_DIR_ADDR)
88 #define gpPageCR3 ((tTabEnt*)PAGE_CR3_ADDR)
89 #define gpTmpCR3 ((tTabEnt*)TMP_CR3_ADDR)
91 #define gaPAE_PageTable ((tTabEnt*)PAE_PAGE_TABLE_ADDR)
92 #define gaPAE_PageDir ((tTabEnt*)PAE_PAGE_DIR_ADDR)
93 #define gaPAE_MainPDPT ((tTabEnt*)PAE_PAGE_PDPT_ADDR)
94 #define gaPAE_TmpTable ((tTabEnt*)PAE_TMP_DIR_ADDR)
95 #define gaPAE_TmpDir ((tTabEnt*)PAE_TMP_DIR_ADDR)
96 #define gaPAE_TmpPDPT ((tTabEnt*)PAE_TMP_PDPT_ADDR)
98 int gilTempMappings = 0;
99 int gilTempFractal = 0;
100 Uint32 gWorkerStacks[(NUM_WORKER_STACKS+31)/32];
101 int giLastUsedWorker = 0;
105 * \fn void MM_PreinitVirtual()
106 * \brief Maps the fractal mappings
108 void MM_PreinitVirtual()
111 gaInitPageDir[ ((PAGE_TABLE_ADDR >> TAB)-3*512+3)*2 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
113 gaInitPageDir[ PAGE_TABLE_ADDR >> 22 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
115 INVLPG( PAGE_TABLE_ADDR );
119 * \fn void MM_InstallVirtual()
120 * \brief Sets up the constant page mappings
122 void MM_InstallVirtual()
127 // --- Pre-Allocate kernel tables
128 for( i = KERNEL_BASE >> TAB; i < 1024*4; i ++ )
130 if( gaPAE_PageDir[ i ] ) continue;
132 // Skip stack tables, they are process unique
133 if( i > KERNEL_STACKS >> TAB && i < KERNEL_STACKS_END >> TAB) {
134 gaPAE_PageDir[ i ] = 0;
138 gaPAE_PageDir[ i ] = MM_AllocPhys() | 3;
139 INVLPG( &gaPAE_PageTable[i*512] );
140 memset( &gaPAE_PageTable[i*512], 0, 0x1000 );
143 // --- Pre-Allocate kernel tables
144 for( i = KERNEL_BASE>>22; i < 1024; i ++ )
146 if( gaPageDir[ i ] ) continue;
147 // Skip stack tables, they are process unique
148 if( i > KERNEL_STACKS >> 22 && i < KERNEL_STACKS_END >> 22) {
153 gaPageDir[ i ] = MM_AllocPhys() | 3;
154 INVLPG( &gaPageTable[i*1024] );
155 memset( &gaPageTable[i*1024], 0, 0x1000 );
159 // Unset kernel on the User Text pages
160 for( i = ((tVAddr)&_UsertextEnd-(tVAddr)&_UsertextBase+0xFFF)/4096; i--; ) {
161 Log("MM_SetFlags( 0x%08x, 0, MM_PFLAG_KERNEL)", (tVAddr)&_UsertextBase + i*4096);
162 MM_SetFlags( (tVAddr)&_UsertextBase + i*4096, 0, MM_PFLAG_KERNEL );
167 * \brief Cleans up the SMP required mappings
169 void MM_FinishVirtualInit()
174 gaInitPageDir[ 0 ] = 0;
179 * \fn void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
180 * \brief Called on a page fault
182 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
184 //ENTER("xAddr bErrorCode", Addr, ErrorCode);
186 // -- Check for COW --
187 if( gaPageDir [Addr>>22] & PF_PRESENT
188 && 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 );
211 // If it was a user, tell the thread handler
213 Warning("%s %s %s memory%s",
214 (ErrorCode&4?"User":"Kernel"),
215 (ErrorCode&2?"write to":"read from"),
216 (ErrorCode&1?"bad/locked":"non-present"),
217 (ErrorCode&16?" (Instruction Fetch)":"")
219 Warning("User Pagefault: Instruction at %04x:%08x accessed %p", Regs->cs, Regs->eip, Addr);
220 __asm__ __volatile__ ("sti"); // Restart IRQs
221 Threads_SegFault(Addr);
227 // -- Check Error Code --
229 Warning("Reserved Bits Trashed!");
232 Warning("%s %s %s memory%s",
233 (ErrorCode&4?"User":"Kernel"),
234 (ErrorCode&2?"write to":"read from"),
235 (ErrorCode&1?"bad/locked":"non-present"),
236 (ErrorCode&16?" (Instruction Fetch)":"")
240 Log("Code at %p accessed %p", Regs->eip, Addr);
241 // Print Stack Backtrace
242 Error_Backtrace(Regs->eip, Regs->ebp);
244 Log("gaPageDir[0x%x] = 0x%x", Addr>>22, gaPageDir[Addr>>22]);
245 if( gaPageDir[Addr>>22] & PF_PRESENT )
246 Log("gaPageTable[0x%x] = 0x%x", Addr>>12, gaPageTable[Addr>>12]);
248 //MM_DumpTables(0, -1);
250 Panic("Page Fault at 0x%x (Accessed 0x%x)", Regs->eip, Addr);
254 * \fn void MM_DumpTables(tVAddr Start, tVAddr End)
255 * \brief Dumps the layout of the page tables
257 void MM_DumpTables(tVAddr Start, tVAddr End)
259 tVAddr rangeStart = 0;
263 const tPAddr MASK = ~0xF98;
265 Start >>= 12; End >>= 12;
268 Log("Directory Entries:");
269 for(page = Start >> 10;
270 page < (End >> 10)+1;
275 Log(" 0x%08x-0x%08x :: 0x%08x",
276 page<<22, ((page+1)<<22)-1,
277 gaPageDir[page]&~0xFFF
283 Log("Table Entries:");
284 for(page = Start, curPos = Start<<12;
286 curPos += 0x1000, page++)
288 if( !(gaPageDir[curPos>>22] & PF_PRESENT)
289 || !(gaPageTable[page] & PF_PRESENT)
290 || (gaPageTable[page] & MASK) != expected)
293 Log(" 0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
294 rangeStart, curPos - 1,
295 gaPageTable[rangeStart>>12] & ~0xFFF,
296 (expected & ~0xFFF) - 1,
297 (expected & PF_PAGED ? "p" : "-"),
298 (expected & PF_COW ? "C" : "-"),
299 (expected & PF_USER ? "U" : "-"),
300 (expected & PF_WRITE ? "W" : "-")
304 if( !(gaPageDir[curPos>>22] & PF_PRESENT) ) continue;
305 if( !(gaPageTable[curPos>>12] & PF_PRESENT) ) continue;
307 expected = (gaPageTable[page] & MASK);
310 if(expected) expected += 0x1000;
314 Log("0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
315 rangeStart, curPos - 1,
316 gaPageTable[rangeStart>>12] & ~0xFFF,
317 (expected & ~0xFFF) - 1,
318 (expected & PF_PAGED ? "p" : "-"),
319 (expected & PF_COW ? "C" : "-"),
320 (expected & PF_USER ? "U" : "-"),
321 (expected & PF_WRITE ? "W" : "-")
328 * \fn tPAddr MM_Allocate(tVAddr VAddr)
330 tPAddr MM_Allocate(tVAddr VAddr)
333 //ENTER("xVAddr", VAddr);
334 //__asm__ __volatile__ ("xchg %bx,%bx");
335 // Check if the directory is mapped
336 if( gaPageDir[ VAddr >> 22 ] == 0 )
338 // Allocate directory
339 paddr = MM_AllocPhys();
340 //LOG("paddr = 0x%llx (new table)", paddr);
342 Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
347 gaPageDir[ VAddr >> 22 ] = paddr | 3;
349 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
351 INVLPG( &gaPageDir[ VAddr >> 22 ] );
352 //LOG("Clearing new table");
353 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
355 // Check if the page is already allocated
356 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
357 Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
358 //LEAVE('X', gaPageTable[ VAddr >> 12 ] & ~0xFFF);
359 return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
363 paddr = MM_AllocPhys();
364 //LOG("paddr = 0x%llx", paddr);
366 Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)",
367 VAddr, __builtin_return_address(0));
372 gaPageTable[ VAddr >> 12 ] = paddr | 3;
374 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
375 // Invalidate Cache for address
376 INVLPG( VAddr & ~0xFFF );
383 * \fn void MM_Deallocate(tVAddr VAddr)
385 void MM_Deallocate(tVAddr VAddr)
387 if( gaPageDir[ VAddr >> 22 ] == 0 ) {
388 Warning("MM_Deallocate - Directory not mapped");
392 if(gaPageTable[ VAddr >> 12 ] == 0) {
393 Warning("MM_Deallocate - Page is not allocated");
398 MM_DerefPhys( gaPageTable[ VAddr >> 12 ] & ~0xFFF );
400 gaPageTable[ VAddr >> 12 ] = 0;
404 * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
405 * \brief Checks if the passed address is accesable
407 tPAddr MM_GetPhysAddr(tVAddr Addr)
409 if( !(gaPageDir[Addr >> 22] & 1) )
411 if( !(gaPageTable[Addr >> 12] & 1) )
413 return (gaPageTable[Addr >> 12] & ~0xFFF) | (Addr & 0xFFF);
418 * \fn int MM_IsUser(tVAddr VAddr)
419 * \brief Checks if a page is user accessable
421 int MM_IsUser(tVAddr VAddr)
423 if( !(gaPageDir[VAddr >> 22] & 1) )
425 if( !(gaPageTable[VAddr >> 12] & 1) )
427 if( !(gaPageTable[VAddr >> 12] & PF_USER) )
433 * \fn void MM_SetCR3(Uint CR3)
434 * \brief Sets the current process space
436 void MM_SetCR3(Uint CR3)
438 __asm__ __volatile__ ("mov %0, %%cr3"::"r"(CR3));
442 * \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
443 * \brief Map a physical page to a virtual one
445 int MM_Map(tVAddr VAddr, tPAddr PAddr)
447 //ENTER("xVAddr xPAddr", VAddr, PAddr);
449 if( PAddr & 0xFFF || VAddr & 0xFFF ) {
450 Warning("MM_Map - Physical or Virtual Addresses are not aligned");
456 PAddr &= ~0xFFF; VAddr &= ~0xFFF;
458 // Check if the directory is mapped
459 if( gaPageDir[ VAddr >> 22 ] == 0 )
461 gaPageDir[ VAddr >> 22 ] = MM_AllocPhys() | 3;
464 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
466 INVLPG( &gaPageTable[ (VAddr >> 12) & ~0x3FF ] );
467 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
469 // Check if the page is already allocated
470 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
471 Warning("MM_Map - Allocating to used address");
477 gaPageTable[ VAddr >> 12 ] = PAddr | 3;
479 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
481 //LOG("gaPageTable[ 0x%x ] = (Uint)%p = 0x%x",
482 // VAddr >> 12, &gaPageTable[ VAddr >> 12 ], gaPageTable[ VAddr >> 12 ]);
487 //LOG("INVLPG( 0x%x )", VAddr);
495 * \fn tVAddr MM_ClearUser()
496 * \brief Clear user's address space
498 tVAddr MM_ClearUser()
503 for( i = 0; i < (MM_USER_MAX>>22); i ++ )
505 // Check if directory is not allocated
506 if( !(gaPageDir[i] & PF_PRESENT) ) {
512 for( j = 0; j < 1024; j ++ )
514 if( gaPageTable[i*1024+j] & 1 )
515 MM_DerefPhys( gaPageTable[i*1024+j] & ~0xFFF );
516 gaPageTable[i*1024+j] = 0;
519 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
521 INVLPG( &gaPageTable[i*1024] );
529 * \fn tPAddr MM_Clone()
530 * \brief Clone the current address space
537 tVAddr kStackBase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
540 LOCK( &gilTempFractal );
542 // Create Directory Table
543 *gpTmpCR3 = MM_AllocPhys() | 3;
545 //LOG("Allocated Directory (%x)", *gpTmpCR3);
546 memsetd( gaTmpDir, 0, 1024 );
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];
582 // Map in kernel tables (and make fractal mapping)
583 for( i = 768; i < 1024; i ++ )
586 if( i == (PAGE_TABLE_ADDR >> 22) ) {
587 gaTmpDir[ PAGE_TABLE_ADDR >> 22 ] = *gpTmpCR3;
591 if( gaPageDir[i] == 0 ) {
596 //LOG("gaPageDir[%x/4] = 0x%x", i*4, gaPageDir[i]);
597 MM_RefPhys( gaPageDir[i] & ~0xFFF );
598 gaTmpDir[i] = gaPageDir[i];
601 // Allocate kernel stack
602 for(i = KERNEL_STACKS >> 22;
603 i < KERNEL_STACKS_END >> 22;
606 // Check if directory is allocated
607 if( (gaPageDir[i] & 1) == 0 ) {
612 // We don't care about other kernel stacks, just the current one
613 if( i != kStackBase >> 22 ) {
614 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
620 gaTmpDir[i] = MM_AllocPhys() | 3;
621 INVLPG( &gaTmpTable[i*1024] );
622 for( j = 0; j < 1024; j ++ )
624 // Is the page allocated? If not, skip
625 if( !(gaPageTable[i*1024+j] & 1) ) {
626 gaTmpTable[i*1024+j] = 0;
630 // We don't care about other kernel stacks
631 if( ((i*1024+j)*4096 & ~(KERNEL_STACK_SIZE-1)) != kStackBase ) {
632 gaTmpTable[i*1024+j] = 0;
637 gaTmpTable[i*1024+j] = MM_AllocPhys() | 3;
639 MM_RefPhys( gaTmpTable[i*1024+j] & ~0xFFF );
641 tmp = (void *) MM_MapTemp( gaTmpTable[i*1024+j] & ~0xFFF );
642 memcpy( tmp, (void *)( (i*1024+j)*0x1000 ), 0x1000 );
643 MM_FreeTemp( (Uint)tmp );
647 ret = *gpTmpCR3 & ~0xFFF;
648 RELEASE( &gilTempFractal );
655 * \fn tVAddr MM_NewKStack()
656 * \brief Create a new kernel stack
658 tVAddr MM_NewKStack()
660 tVAddr base = KERNEL_STACKS;
662 for(;base<KERNEL_STACKS_END;base+=KERNEL_STACK_SIZE)
664 if(MM_GetPhysAddr(base) != 0) continue;
665 for(i=0;i<KERNEL_STACK_SIZE;i+=0x1000) {
668 return base+KERNEL_STACK_SIZE;
670 Warning("MM_NewKStack - No address space left\n");
675 * \fn tVAddr MM_NewWorkerStack()
676 * \brief Creates a new worker stack
678 tVAddr MM_NewWorkerStack()
685 tPAddr pages[WORKER_STACK_SIZE>>12];
687 // Get the old ESP and EBP
688 __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
689 __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
691 // Find a free worker stack address
692 for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
695 if( gWorkerStacks[base/32] == -1 ) {
696 base += 31; base &= ~31;
697 base --; // Counteracted by the base++
701 if( gWorkerStacks[base/32] & (1 << base) ) {
706 if(base >= NUM_WORKER_STACKS) {
707 Warning("Uh-oh! Out of worker stacks");
712 gWorkerStacks[base/32] |= (1 << base);
713 // Make life easier for later calls
714 giLastUsedWorker = base;
716 base = WORKER_STACKS + base * WORKER_STACK_SIZE;
717 //Log(" MM_NewWorkerStack: base = 0x%x", base);
719 // Acquire the lock for the temp fractal mappings
720 LOCK(&gilTempFractal);
722 // Set the temp fractals to TID0's address space
723 *gpTmpCR3 = ((Uint)gaInitPageDir - KERNEL_BASE) | 3;
724 //Log(" MM_NewWorkerStack: *gpTmpCR3 = 0x%x", *gpTmpCR3);
728 // Check if the directory is mapped (we are assuming that the stacks
729 // will fit neatly in a directory)
730 //Log(" MM_NewWorkerStack: gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
731 if(gaTmpDir[ base >> 22 ] == 0) {
732 gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
733 INVLPG( &gaTmpTable[ (base>>12) & ~0x3FF ] );
737 for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
739 pages[ addr >> 12 ] = MM_AllocPhys();
740 gaTmpTable[ (base + addr) >> 12 ] = pages[addr>>12] | 3;
743 // Release the temp mapping lock
744 RELEASE(&gilTempFractal);
746 // Copy the old stack
747 oldstack = (esp + KERNEL_STACK_SIZE-1) & ~(KERNEL_STACK_SIZE-1);
748 esp = oldstack - esp; // ESP as an offset in the stack
750 // Make `base` be the top of the stack
751 base += WORKER_STACK_SIZE;
753 i = (WORKER_STACK_SIZE>>12) - 1;
754 // Copy the contents of the old stack to the new one, altering the addresses
755 // `addr` is refering to bytes from the stack base (mem downwards)
756 for(addr = 0; addr < esp; addr += 0x1000)
758 Uint *stack = (Uint*)( oldstack-(addr+0x1000) );
759 tmpPage = (void*)MM_MapTemp( pages[i] );
761 for(j = 0; j < 1024; j++)
763 // Possible Stack address?
764 if(oldstack-esp < stack[j] && stack[j] < oldstack)
765 tmpPage[j] = base - (oldstack - stack[j]);
766 else // Seems not, best leave it alone
767 tmpPage[j] = stack[j];
769 MM_FreeTemp((tVAddr)tmpPage);
773 //Log("MM_NewWorkerStack: RETURN 0x%x", base);
778 * \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
779 * \brief Sets the flags on a page
781 void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
784 if( !(gaPageDir[VAddr >> 22] & 1) ) return ;
785 if( !(gaPageTable[VAddr >> 12] & 1) ) return ;
787 ent = &gaPageTable[VAddr >> 12];
790 if( Mask & MM_PFLAG_RO )
792 if( Flags & MM_PFLAG_RO ) {
796 gaPageDir[VAddr >> 22] |= PF_WRITE;
802 if( Mask & MM_PFLAG_KERNEL )
804 if( Flags & MM_PFLAG_KERNEL ) {
808 gaPageDir[VAddr >> 22] |= PF_USER;
814 if( Mask & MM_PFLAG_COW )
816 if( Flags & MM_PFLAG_COW ) {
826 //Log("MM_SetFlags: *ent = 0x%08x, gaPageDir[%i] = 0x%08x",
827 // *ent, VAddr >> 22, gaPageDir[VAddr >> 22]);
831 * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
832 * \brief Duplicates a virtual page to a physical one
834 tPAddr MM_DuplicatePage(tVAddr VAddr)
840 //ENTER("xVAddr", VAddr);
843 if( !(gaPageDir [VAddr >> 22] & PF_PRESENT) ) return 0;
844 if( !(gaPageTable[VAddr >> 12] & PF_PRESENT) ) return 0;
850 ret = MM_AllocPhys();
852 // Write-lock the page (to keep data constistent), saving its R/W state
853 wasRO = (gaPageTable[VAddr >> 12] & PF_WRITE ? 0 : 1);
854 gaPageTable[VAddr >> 12] &= ~PF_WRITE;
858 temp = MM_MapTemp(ret);
859 memcpy( (void*)temp, (void*)VAddr, 0x1000 );
862 // Restore Writeable status
863 if(!wasRO) gaPageTable[VAddr >> 12] |= PF_WRITE;
871 * \fn Uint MM_MapTemp(tPAddr PAddr)
872 * \brief Create a temporary memory mapping
873 * \todo Show Luigi Barone (C Lecturer) and see what he thinks
875 tVAddr MM_MapTemp(tPAddr PAddr)
879 //ENTER("XPAddr", PAddr);
883 //LOG("gilTempMappings = %i", gilTempMappings);
887 LOCK( &gilTempMappings );
889 for( i = 0; i < NUM_TEMP_PAGES; i ++ )
891 // Check if page used
892 if(gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] & 1) continue;
894 gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] = PAddr | 3;
895 INVLPG( TEMP_MAP_ADDR + (i << 12) );
896 //LEAVE('p', TEMP_MAP_ADDR + (i << 12));
897 RELEASE( &gilTempMappings );
898 return TEMP_MAP_ADDR + (i << 12);
900 RELEASE( &gilTempMappings );
906 * \fn void MM_FreeTemp(tVAddr PAddr)
907 * \brief Free's a temp mapping
909 void MM_FreeTemp(tVAddr VAddr)
912 //ENTER("xVAddr", VAddr);
914 if(i >= (TEMP_MAP_ADDR >> 12))
915 gaPageTable[ i ] = 0;
921 * \fn tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
922 * \brief Allocates a contigous number of pages
924 tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
931 for( i = 0; i < NUM_HW_PAGES; i ++ )
933 // Check if addr used
934 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i ] & 1 )
937 // Check possible region
938 for( j = 0; j < Number && i + j < NUM_HW_PAGES; j ++ )
940 // If there is an allocated page in the region we are testing, break
941 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] & 1 ) break;
947 for( j = 0; j < Number; j++ ) {
948 MM_RefPhys( PAddr + (j<<12) );
949 gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] = (PAddr + (j<<12)) | 3;
951 return HW_MAP_ADDR + (i<<12);
954 // If we don't find any, return NULL
959 * \fn tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
960 * \brief Allocates DMA physical memory
961 * \param Pages Number of pages required
962 * \param MaxBits Maximum number of bits the physical address can have
963 * \param PhysAddr Pointer to the location to place the physical address allocated
964 * \return Virtual address allocate
966 tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
968 tPAddr maxCheck = (1 << MaxBits);
972 ENTER("iPages iMaxBits pPhysAddr", Pages, MaxBits, PhysAddr);
975 if(MaxBits < 12 || !PhysAddr) {
981 if(MaxBits >= PHYS_BITS) maxCheck = -1;
984 if(Pages == 1 && MaxBits >= PHYS_BITS)
986 phys = MM_AllocPhys();
988 ret = MM_MapHWPages(phys, 1);
999 phys = MM_AllocPhysRange(Pages, MaxBits);
1000 // - Was it allocated?
1006 // Allocated successfully, now map
1007 ret = MM_MapHWPages(phys, Pages);
1009 // If it didn't map, free then return 0
1010 for(;Pages--;phys+=0x1000)
1022 * \fn void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1023 * \brief Unmap a hardware page
1025 void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1029 //Log_Debug("VirtMem", "MM_UnmapHWPages: (VAddr=0x%08x, Number=%i)", VAddr, Number);
1032 if(VAddr < HW_MAP_ADDR || VAddr+Number*0x1000 > HW_MAP_MAX) return;
1036 LOCK( &gilTempMappings ); // Temp and HW share a directory, so they share a lock
1039 for( j = 0; j < Number; j++ )
1041 MM_DerefPhys( gaPageTable[ i + j ] & ~0xFFF );
1042 gaPageTable[ i + j ] = 0;
1045 RELEASE( &gilTempMappings );
1049 EXPORT(MM_GetPhysAddr);
1052 EXPORT(MM_MapHWPages);
1053 EXPORT(MM_AllocDMA);
1054 EXPORT(MM_UnmapHWPages);