2 * AcessOS Microkernel Version
10 * 0xFF - System Calls / Kernel's User Code
25 #define KERNEL_STACKS 0xF0000000
26 #define KERNEL_STACK_SIZE 0x00008000
27 #define KERNEL_STACKS_END 0xFC000000
28 #define WORKER_STACKS 0x00100000 // Thread0 Only!
29 #define WORKER_STACK_SIZE KERNEL_STACK_SIZE
30 #define WORKER_STACKS_END 0xB0000000
31 #define NUM_WORKER_STACKS ((WORKER_STACKS_END-WORKER_STACKS)/WORKER_STACK_SIZE)
33 #define PAE_PAGE_TABLE_ADDR 0xFC000000 // 16 MiB
34 #define PAE_PAGE_DIR_ADDR 0xFCFC0000 // 16 KiB
35 #define PAE_PAGE_PDPT_ADDR 0xFCFC3F00 // 32 bytes
36 #define PAE_TMP_PDPT_ADDR 0xFCFC3F20 // 32 bytes
37 #define PAE_TMP_DIR_ADDR 0xFCFE0000 // 16 KiB
38 #define PAE_TMP_TABLE_ADDR 0xFD000000 // 16 MiB
40 #define PAGE_TABLE_ADDR 0xFC000000
41 #define PAGE_DIR_ADDR 0xFC3F0000
42 #define PAGE_CR3_ADDR 0xFC3F0FC0
43 #define TMP_CR3_ADDR 0xFC3F0FC4 // Part of core instead of temp
44 #define TMP_DIR_ADDR 0xFC3F1000 // Same
45 #define TMP_TABLE_ADDR 0xFC400000
47 #define HW_MAP_ADDR 0xFE000000
48 #define HW_MAP_MAX 0xFFEF0000
49 #define NUM_HW_PAGES ((HW_MAP_MAX-HW_MAP_ADDR)/0x1000)
50 #define TEMP_MAP_ADDR 0xFFEF0000 // Allows 16 "temp" pages
51 #define NUM_TEMP_PAGES 16
52 #define LAST_BLOCK_ADDR 0xFFFF0000 // Free space for kernel provided user code/ *(-1) protection
54 #define PF_PRESENT 0x1
58 #define PF_PAGED 0x400
60 #define INVLPG(addr) __asm__ __volatile__ ("invlpg (%0)"::"r"(addr))
63 typedef Uint64 tTabEnt;
65 typedef Uint32 tTabEnt;
69 extern void _UsertextEnd, _UsertextBase;
70 extern Uint32 gaInitPageDir[1024];
71 extern Uint32 gaInitPageTable[1024];
72 extern void Threads_SegFault(tVAddr Addr);
73 extern void Error_Backtrace(Uint eip, Uint ebp);
76 void MM_PreinitVirtual();
77 void MM_InstallVirtual();
78 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
79 void MM_DumpTables(tVAddr Start, tVAddr End);
80 tPAddr MM_DuplicatePage(tVAddr VAddr);
83 #define gaPageTable ((tTabEnt*)PAGE_TABLE_ADDR)
84 #define gaPageDir ((tTabEnt*)PAGE_DIR_ADDR)
85 #define gaTmpTable ((tTabEnt*)TMP_TABLE_ADDR)
86 #define gaTmpDir ((tTabEnt*)TMP_DIR_ADDR)
87 #define gpPageCR3 ((tTabEnt*)PAGE_CR3_ADDR)
88 #define gpTmpCR3 ((tTabEnt*)TMP_CR3_ADDR)
90 #define gaPAE_PageTable ((tTabEnt*)PAE_PAGE_TABLE_ADDR)
91 #define gaPAE_PageDir ((tTabEnt*)PAE_PAGE_DIR_ADDR)
92 #define gaPAE_MainPDPT ((tTabEnt*)PAE_PAGE_PDPT_ADDR)
93 #define gaPAE_TmpTable ((tTabEnt*)PAE_TMP_DIR_ADDR)
94 #define gaPAE_TmpDir ((tTabEnt*)PAE_TMP_DIR_ADDR)
95 #define gaPAE_TmpPDPT ((tTabEnt*)PAE_TMP_PDPT_ADDR)
97 int gilTempMappings = 0;
98 int gilTempFractal = 0;
99 Uint32 gWorkerStacks[(NUM_WORKER_STACKS+31)/32];
100 int giLastUsedWorker = 0;
104 * \fn void MM_PreinitVirtual()
105 * \brief Maps the fractal mappings
107 void MM_PreinitVirtual()
110 gaInitPageDir[ ((PAGE_TABLE_ADDR >> TAB)-3*512+3)*2 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
112 gaInitPageDir[ PAGE_TABLE_ADDR >> 22 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
114 INVLPG( PAGE_TABLE_ADDR );
118 * \fn void MM_InstallVirtual()
119 * \brief Sets up the constant page mappings
121 void MM_InstallVirtual()
126 // --- Pre-Allocate kernel tables
127 for( i = KERNEL_BASE >> TAB; i < 1024*4; i ++ )
129 if( gaPAE_PageDir[ i ] ) continue;
131 // Skip stack tables, they are process unique
132 if( i > KERNEL_STACKS >> TAB && i < KERNEL_STACKS_END >> TAB) {
133 gaPAE_PageDir[ i ] = 0;
137 gaPAE_PageDir[ i ] = MM_AllocPhys() | 3;
138 INVLPG( &gaPAE_PageTable[i*512] );
139 memset( &gaPAE_PageTable[i*512], 0, 0x1000 );
142 // --- Pre-Allocate kernel tables
143 for( i = KERNEL_BASE>>22; i < 1024; i ++ )
145 if( gaPageDir[ i ] ) continue;
146 // Skip stack tables, they are process unique
147 if( i > KERNEL_STACKS >> 22 && i < KERNEL_STACKS_END >> 22) {
152 gaPageDir[ i ] = MM_AllocPhys() | 3;
153 INVLPG( &gaPageTable[i*1024] );
154 memset( &gaPageTable[i*1024], 0, 0x1000 );
158 // Unset kernel on the User Text pages
159 for( i = ((tVAddr)&_UsertextEnd-(tVAddr)&_UsertextBase+0xFFF)/4096; i--; ) {
160 Log("MM_SetFlags( 0x%08x, 0, MM_PFLAG_KERNEL)", (tVAddr)&_UsertextBase + i*4096);
161 MM_SetFlags( (tVAddr)&_UsertextBase + i*4096, 0, MM_PFLAG_KERNEL );
166 * \brief Cleans up the SMP required mappings
168 void MM_FinishVirtualInit()
173 gaInitPageDir[ 0 ] = 0;
178 * \fn void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
179 * \brief Called on a page fault
181 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
183 //ENTER("xAddr bErrorCode", Addr, ErrorCode);
185 // -- Check for COW --
186 if( gaPageDir [Addr>>22] & PF_PRESENT
187 && gaPageTable[Addr>>12] & PF_PRESENT
188 && gaPageTable[Addr>>12] & PF_COW )
191 if(MM_GetRefCount( gaPageTable[Addr>>12] & ~0xFFF ) == 1)
193 gaPageTable[Addr>>12] &= ~PF_COW;
194 gaPageTable[Addr>>12] |= PF_PRESENT|PF_WRITE;
198 //Log("MM_PageFault: COW - MM_DuplicatePage(0x%x)", Addr);
199 paddr = MM_DuplicatePage( Addr );
200 MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF );
201 gaPageTable[Addr>>12] &= PF_USER;
202 gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE;
205 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
220 Threads_SegFault(Addr);
226 // -- Check Error Code --
228 Warning("Reserved Bits Trashed!");
231 Warning("%s %s %s memory%s",
232 (ErrorCode&4?"User":"Kernel"),
233 (ErrorCode&2?"write to":"read from"),
234 (ErrorCode&1?"bad/locked":"non-present"),
235 (ErrorCode&16?" (Instruction Fetch)":"")
239 Log("Code at %p accessed %p", Regs->eip, Addr);
240 // Print Stack Backtrace
241 Error_Backtrace(Regs->eip, Regs->ebp);
243 Log("gaPageDir[0x%x] = 0x%x", Addr>>22, gaPageDir[Addr>>22]);
244 if( gaPageDir[Addr>>22] & PF_PRESENT )
245 Log("gaPageTable[0x%x] = 0x%x", Addr>>12, gaPageTable[Addr>>12]);
247 //MM_DumpTables(0, -1);
249 Panic("Page Fault at 0x%x (Accessed 0x%x)", Regs->eip, Addr);
253 * \fn void MM_DumpTables(tVAddr Start, tVAddr End)
254 * \brief Dumps the layout of the page tables
256 void MM_DumpTables(tVAddr Start, tVAddr End)
258 tVAddr rangeStart = 0;
262 const tPAddr MASK = ~0xF98;
264 Start >>= 12; End >>= 12;
267 Log("Directory Entries:");
268 for(page = Start >> 10;
269 page < (End >> 10)+1;
274 Log(" 0x%08x-0x%08x :: 0x%08x",
275 page<<22, ((page+1)<<22)-1,
276 gaPageDir[page]&~0xFFF
282 Log("Table Entries:");
283 for(page = Start, curPos = Start<<12;
285 curPos += 0x1000, page++)
287 if( !(gaPageDir[curPos>>22] & PF_PRESENT)
288 || !(gaPageTable[page] & PF_PRESENT)
289 || (gaPageTable[page] & MASK) != expected)
292 Log(" 0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
293 rangeStart, curPos - 1,
294 gaPageTable[rangeStart>>12] & ~0xFFF,
295 (expected & ~0xFFF) - 1,
296 (expected & PF_PAGED ? "p" : "-"),
297 (expected & PF_COW ? "C" : "-"),
298 (expected & PF_USER ? "U" : "-"),
299 (expected & PF_WRITE ? "W" : "-")
303 if( !(gaPageDir[curPos>>22] & PF_PRESENT) ) continue;
304 if( !(gaPageTable[curPos>>12] & PF_PRESENT) ) continue;
306 expected = (gaPageTable[page] & MASK);
309 if(expected) expected += 0x1000;
313 Log("0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
314 rangeStart, curPos - 1,
315 gaPageTable[rangeStart>>12] & ~0xFFF,
316 (expected & ~0xFFF) - 1,
317 (expected & PF_PAGED ? "p" : "-"),
318 (expected & PF_COW ? "C" : "-"),
319 (expected & PF_USER ? "U" : "-"),
320 (expected & PF_WRITE ? "W" : "-")
327 * \fn tPAddr MM_Allocate(tVAddr VAddr)
329 tPAddr MM_Allocate(tVAddr VAddr)
332 //ENTER("xVAddr", VAddr);
333 //__asm__ __volatile__ ("xchg %bx,%bx");
334 // Check if the directory is mapped
335 if( gaPageDir[ VAddr >> 22 ] == 0 )
337 // Allocate directory
338 paddr = MM_AllocPhys();
339 //LOG("paddr = 0x%llx (new table)", paddr);
341 Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
346 gaPageDir[ VAddr >> 22 ] = paddr | 3;
348 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
350 INVLPG( &gaPageDir[ VAddr >> 22 ] );
351 //LOG("Clearing new table");
352 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
354 // Check if the page is already allocated
355 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
356 Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
357 //LEAVE('X', gaPageTable[ VAddr >> 12 ] & ~0xFFF);
358 return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
362 paddr = MM_AllocPhys();
363 //LOG("paddr = 0x%llx", paddr);
365 Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)",
366 VAddr, __builtin_return_address(0));
371 gaPageTable[ VAddr >> 12 ] = paddr | 3;
373 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
374 // Invalidate Cache for address
375 INVLPG( VAddr & ~0xFFF );
382 * \fn void MM_Deallocate(tVAddr VAddr)
384 void MM_Deallocate(tVAddr VAddr)
386 if( gaPageDir[ VAddr >> 22 ] == 0 ) {
387 Warning("MM_Deallocate - Directory not mapped");
391 if(gaPageTable[ VAddr >> 12 ] == 0) {
392 Warning("MM_Deallocate - Page is not allocated");
397 MM_DerefPhys( gaPageTable[ VAddr >> 12 ] & ~0xFFF );
399 gaPageTable[ VAddr >> 12 ] = 0;
403 * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
404 * \brief Checks if the passed address is accesable
406 tPAddr MM_GetPhysAddr(tVAddr Addr)
408 if( !(gaPageDir[Addr >> 22] & 1) )
410 if( !(gaPageTable[Addr >> 12] & 1) )
412 return (gaPageTable[Addr >> 12] & ~0xFFF) | (Addr & 0xFFF);
417 * \fn int MM_IsUser(tVAddr VAddr)
418 * \brief Checks if a page is user accessable
420 int MM_IsUser(tVAddr VAddr)
422 if( !(gaPageDir[VAddr >> 22] & 1) )
424 if( !(gaPageTable[VAddr >> 12] & 1) )
426 if( !(gaPageTable[VAddr >> 12] & PF_USER) )
432 * \fn void MM_SetCR3(tPAddr CR3)
433 * \brief Sets the current process space
435 void MM_SetCR3(tPAddr CR3)
437 __asm__ __volatile__ ("mov %0, %%cr3"::"r"(CR3));
441 * \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
442 * \brief Map a physical page to a virtual one
444 int MM_Map(tVAddr VAddr, tPAddr PAddr)
446 //ENTER("xVAddr xPAddr", VAddr, PAddr);
448 if( PAddr & 0xFFF || VAddr & 0xFFF ) {
449 Warning("MM_Map - Physical or Virtual Addresses are not aligned");
455 PAddr &= ~0xFFF; VAddr &= ~0xFFF;
457 // Check if the directory is mapped
458 if( gaPageDir[ VAddr >> 22 ] == 0 )
460 gaPageDir[ VAddr >> 22 ] = MM_AllocPhys() | 3;
463 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
465 INVLPG( &gaPageTable[ (VAddr >> 12) & ~0x3FF ] );
466 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
468 // Check if the page is already allocated
469 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
470 Warning("MM_Map - Allocating to used address");
476 gaPageTable[ VAddr >> 12 ] = PAddr | 3;
478 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
480 //LOG("gaPageTable[ 0x%x ] = (Uint)%p = 0x%x",
481 // VAddr >> 12, &gaPageTable[ VAddr >> 12 ], gaPageTable[ VAddr >> 12 ]);
486 //LOG("INVLPG( 0x%x )", VAddr);
494 * \fn tVAddr MM_ClearUser()
495 * \brief Clear user's address space
497 tVAddr MM_ClearUser()
502 for( i = 0; i < (MM_USER_MAX>>22); i ++ )
504 // Check if directory is not allocated
505 if( !(gaPageDir[i] & PF_PRESENT) ) {
511 for( j = 0; j < 1024; j ++ )
513 if( gaPageTable[i*1024+j] & 1 )
514 MM_DerefPhys( gaPageTable[i*1024+j] & ~0xFFF );
515 gaPageTable[i*1024+j] = 0;
518 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
520 INVLPG( &gaPageTable[i*1024] );
528 * \fn tPAddr MM_Clone()
529 * \brief Clone the current address space
536 tVAddr kStackBase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
539 LOCK( &gilTempFractal );
541 // Create Directory Table
542 *gpTmpCR3 = MM_AllocPhys() | 3;
544 //LOG("Allocated Directory (%x)", *gpTmpCR3);
545 memsetd( gaTmpDir, 0, 1024 );
548 for( i = 0; i < 768; i ++)
550 // Check if table is allocated
551 if( !(gaPageDir[i] & PF_PRESENT) ) {
557 // Allocate new table
558 gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
559 INVLPG( &gaTmpTable[page] );
561 for( j = 0; j < 1024; j ++, page++ )
563 if( !(gaPageTable[page] & PF_PRESENT) ) {
564 gaTmpTable[page] = 0;
569 MM_RefPhys( gaPageTable[page] & ~0xFFF );
571 if(gaPageTable[page] & PF_WRITE) {
572 gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
573 gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
574 INVLPG( page << 12 );
577 gaTmpTable[page] = gaPageTable[page];
581 // Map in kernel tables (and make fractal mapping)
582 for( i = 768; i < 1024; i ++ )
585 if( i == (PAGE_TABLE_ADDR >> 22) ) {
586 gaTmpDir[ PAGE_TABLE_ADDR >> 22 ] = *gpTmpCR3;
590 if( gaPageDir[i] == 0 ) {
595 //LOG("gaPageDir[%x/4] = 0x%x", i*4, gaPageDir[i]);
596 MM_RefPhys( gaPageDir[i] & ~0xFFF );
597 gaTmpDir[i] = gaPageDir[i];
600 // Allocate kernel stack
601 for(i = KERNEL_STACKS >> 22;
602 i < KERNEL_STACKS_END >> 22;
605 // Check if directory is allocated
606 if( (gaPageDir[i] & 1) == 0 ) {
611 // We don't care about other kernel stacks, just the current one
612 if( i != kStackBase >> 22 ) {
613 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
619 gaTmpDir[i] = MM_AllocPhys() | 3;
620 INVLPG( &gaTmpTable[i*1024] );
621 for( j = 0; j < 1024; j ++ )
623 // Is the page allocated? If not, skip
624 if( !(gaPageTable[i*1024+j] & 1) ) {
625 gaTmpTable[i*1024+j] = 0;
629 // We don't care about other kernel stacks
630 if( ((i*1024+j)*4096 & ~(KERNEL_STACK_SIZE-1)) != kStackBase ) {
631 gaTmpTable[i*1024+j] = 0;
636 gaTmpTable[i*1024+j] = MM_AllocPhys() | 3;
638 MM_RefPhys( gaTmpTable[i*1024+j] & ~0xFFF );
640 tmp = (void *) MM_MapTemp( gaTmpTable[i*1024+j] & ~0xFFF );
641 memcpy( tmp, (void *)( (i*1024+j)*0x1000 ), 0x1000 );
642 MM_FreeTemp( (Uint)tmp );
646 ret = *gpTmpCR3 & ~0xFFF;
647 RELEASE( &gilTempFractal );
654 * \fn tVAddr MM_NewKStack()
655 * \brief Create a new kernel stack
657 tVAddr MM_NewKStack()
659 tVAddr base = KERNEL_STACKS;
661 for(;base<KERNEL_STACKS_END;base+=KERNEL_STACK_SIZE)
663 if(MM_GetPhysAddr(base) != 0) continue;
664 for(i=0;i<KERNEL_STACK_SIZE;i+=0x1000) {
667 return base+KERNEL_STACK_SIZE;
669 Warning("MM_NewKStack - No address space left\n");
674 * \fn tVAddr MM_NewWorkerStack()
675 * \brief Creates a new worker stack
677 tVAddr MM_NewWorkerStack()
684 tPAddr pages[WORKER_STACK_SIZE>>12];
686 // Get the old ESP and EBP
687 __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
688 __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
690 // Find a free worker stack address
691 for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
694 if( gWorkerStacks[base/32] == -1 ) {
695 base += 31; base &= ~31;
696 base --; // Counteracted by the base++
700 if( gWorkerStacks[base/32] & (1 << base) ) {
705 if(base >= NUM_WORKER_STACKS) {
706 Warning("Uh-oh! Out of worker stacks");
711 gWorkerStacks[base/32] |= (1 << base);
712 // Make life easier for later calls
713 giLastUsedWorker = base;
715 base = WORKER_STACKS + base * WORKER_STACK_SIZE;
716 //Log(" MM_NewWorkerStack: base = 0x%x", base);
718 // Acquire the lock for the temp fractal mappings
719 LOCK(&gilTempFractal);
721 // Set the temp fractals to TID0's address space
722 *gpTmpCR3 = ((Uint)gaInitPageDir - KERNEL_BASE) | 3;
723 //Log(" MM_NewWorkerStack: *gpTmpCR3 = 0x%x", *gpTmpCR3);
727 // Check if the directory is mapped (we are assuming that the stacks
728 // will fit neatly in a directory)
729 //Log(" MM_NewWorkerStack: gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
730 if(gaTmpDir[ base >> 22 ] == 0) {
731 gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
732 INVLPG( &gaTmpTable[ (base>>12) & ~0x3FF ] );
736 for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
738 pages[ addr >> 12 ] = MM_AllocPhys();
739 gaTmpTable[ (base + addr) >> 12 ] = pages[addr>>12] | 3;
742 // Release the temp mapping lock
743 RELEASE(&gilTempFractal);
745 // Copy the old stack
746 oldstack = (esp + KERNEL_STACK_SIZE-1) & ~(KERNEL_STACK_SIZE-1);
747 esp = oldstack - esp; // ESP as an offset in the stack
749 // Make `base` be the top of the stack
750 base += WORKER_STACK_SIZE;
752 i = (WORKER_STACK_SIZE>>12) - 1;
753 // Copy the contents of the old stack to the new one, altering the addresses
754 // `addr` is refering to bytes from the stack base (mem downwards)
755 for(addr = 0; addr < esp; addr += 0x1000)
757 Uint *stack = (Uint*)( oldstack-(addr+0x1000) );
758 tmpPage = (void*)MM_MapTemp( pages[i] );
760 for(j = 0; j < 1024; j++)
762 // Possible Stack address?
763 if(oldstack-esp < stack[j] && stack[j] < oldstack)
764 tmpPage[j] = base - (oldstack - stack[j]);
765 else // Seems not, best leave it alone
766 tmpPage[j] = stack[j];
768 MM_FreeTemp((tVAddr)tmpPage);
772 //Log("MM_NewWorkerStack: RETURN 0x%x", base);
777 * \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
778 * \brief Sets the flags on a page
780 void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
783 if( !(gaPageDir[VAddr >> 22] & 1) ) return ;
784 if( !(gaPageTable[VAddr >> 12] & 1) ) return ;
786 ent = &gaPageTable[VAddr >> 12];
789 if( Mask & MM_PFLAG_RO )
791 if( Flags & MM_PFLAG_RO ) {
795 gaPageDir[VAddr >> 22] |= PF_WRITE;
801 if( Mask & MM_PFLAG_KERNEL )
803 if( Flags & MM_PFLAG_KERNEL ) {
807 gaPageDir[VAddr >> 22] |= PF_USER;
813 if( Mask & MM_PFLAG_COW )
815 if( Flags & MM_PFLAG_COW ) {
825 //Log("MM_SetFlags: *ent = 0x%08x, gaPageDir[%i] = 0x%08x",
826 // *ent, VAddr >> 22, gaPageDir[VAddr >> 22]);
830 * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
831 * \brief Duplicates a virtual page to a physical one
833 tPAddr MM_DuplicatePage(tVAddr VAddr)
839 //ENTER("xVAddr", VAddr);
842 if( !(gaPageDir [VAddr >> 22] & PF_PRESENT) ) return 0;
843 if( !(gaPageTable[VAddr >> 12] & PF_PRESENT) ) return 0;
849 ret = MM_AllocPhys();
851 // Write-lock the page (to keep data constistent), saving its R/W state
852 wasRO = (gaPageTable[VAddr >> 12] & PF_WRITE ? 0 : 1);
853 gaPageTable[VAddr >> 12] &= ~PF_WRITE;
857 temp = MM_MapTemp(ret);
858 memcpy( (void*)temp, (void*)VAddr, 0x1000 );
861 // Restore Writeable status
862 if(!wasRO) gaPageTable[VAddr >> 12] |= PF_WRITE;
870 * \fn Uint MM_MapTemp(tPAddr PAddr)
871 * \brief Create a temporary memory mapping
872 * \todo Show Luigi Barone (C Lecturer) and see what he thinks
874 tVAddr MM_MapTemp(tPAddr PAddr)
878 //ENTER("XPAddr", PAddr);
882 //LOG("gilTempMappings = %i", gilTempMappings);
886 LOCK( &gilTempMappings );
888 for( i = 0; i < NUM_TEMP_PAGES; i ++ )
890 // Check if page used
891 if(gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] & 1) continue;
893 gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] = PAddr | 3;
894 INVLPG( TEMP_MAP_ADDR + (i << 12) );
895 //LEAVE('p', TEMP_MAP_ADDR + (i << 12));
896 RELEASE( &gilTempMappings );
897 return TEMP_MAP_ADDR + (i << 12);
899 RELEASE( &gilTempMappings );
905 * \fn void MM_FreeTemp(tVAddr PAddr)
906 * \brief Free's a temp mapping
908 void MM_FreeTemp(tVAddr VAddr)
911 //ENTER("xVAddr", VAddr);
913 if(i >= (TEMP_MAP_ADDR >> 12))
914 gaPageTable[ i ] = 0;
920 * \fn tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
921 * \brief Allocates a contigous number of pages
923 tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
930 for( i = 0; i < NUM_HW_PAGES; i ++ )
932 // Check if addr used
933 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i ] & 1 )
936 // Check possible region
937 for( j = 0; j < Number && i + j < NUM_HW_PAGES; j ++ )
939 // If there is an allocated page in the region we are testing, break
940 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] & 1 ) break;
946 for( j = 0; j < Number; j++ ) {
947 MM_RefPhys( PAddr + (j<<12) );
948 gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] = (PAddr + (j<<12)) | 3;
950 return HW_MAP_ADDR + (i<<12);
953 // If we don't find any, return NULL
958 * \fn tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
959 * \brief Allocates DMA physical memory
960 * \param Pages Number of pages required
961 * \param MaxBits Maximum number of bits the physical address can have
962 * \param PhysAddr Pointer to the location to place the physical address allocated
963 * \return Virtual address allocate
965 tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
967 tPAddr maxCheck = (1 << MaxBits);
971 ENTER("iPages iMaxBits pPhysAddr", Pages, MaxBits, PhysAddr);
974 if(MaxBits < 12 || !PhysAddr) {
980 if(MaxBits >= PHYS_BITS) maxCheck = -1;
983 if(Pages == 1 && MaxBits >= PHYS_BITS)
985 phys = MM_AllocPhys();
987 ret = MM_MapHWPages(phys, 1);
998 phys = MM_AllocPhysRange(Pages, MaxBits);
999 // - Was it allocated?
1005 // Allocated successfully, now map
1006 ret = MM_MapHWPages(phys, Pages);
1008 // If it didn't map, free then return 0
1009 for(;Pages--;phys+=0x1000)
1021 * \fn void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1022 * \brief Unmap a hardware page
1024 void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1028 //Log_Debug("VirtMem", "MM_UnmapHWPages: (VAddr=0x%08x, Number=%i)", VAddr, Number);
1031 if(VAddr < HW_MAP_ADDR || VAddr+Number*0x1000 > HW_MAP_MAX) return;
1035 LOCK( &gilTempMappings ); // Temp and HW share a directory, so they share a lock
1038 for( j = 0; j < Number; j++ )
1040 MM_DerefPhys( gaPageTable[ i + j ] & ~0xFFF );
1041 gaPageTable[ i + j ] = 0;
1044 RELEASE( &gilTempMappings );
1048 EXPORT(MM_GetPhysAddr);
1051 EXPORT(MM_MapHWPages);
1052 EXPORT(MM_AllocDMA);
1053 EXPORT(MM_UnmapHWPages);