2 * AcessOS Microkernel Version
10 * 0xFF - System Calls / Kernel's User Code
22 #define KERNEL_STACKS 0xF0000000
23 #define KERNEL_STACK_SIZE 0x00008000
24 #define KERNEL_STACKS_END 0xFC000000
25 #define WORKER_STACKS 0x00100000 // Thread0 Only!
26 #define WORKER_STACK_SIZE KERNEL_STACK_SIZE
27 #define WORKER_STACKS_END 0xB0000000
28 #define NUM_WORKER_STACKS ((WORKER_STACKS_END-WORKER_STACKS)/WORKER_STACK_SIZE)
30 #define PAE_PAGE_TABLE_ADDR 0xFC000000 // 16 MiB
31 #define PAE_PAGE_DIR_ADDR 0xFCFC0000 // 16 KiB
32 #define PAE_PAGE_PDPT_ADDR 0xFCFC3F00 // 32 bytes
33 #define PAE_TMP_PDPT_ADDR 0xFCFC3F20 // 32 bytes
34 #define PAE_TMP_DIR_ADDR 0xFCFE0000 // 16 KiB
35 #define PAE_TMP_TABLE_ADDR 0xFD000000 // 16 MiB
37 #define PAGE_TABLE_ADDR 0xFC000000
38 #define PAGE_DIR_ADDR 0xFC3F0000
39 #define PAGE_CR3_ADDR 0xFC3F0FC0
40 #define TMP_CR3_ADDR 0xFC3F0FC4 // Part of core instead of temp
41 #define TMP_DIR_ADDR 0xFC3F1000 // Same
42 #define TMP_TABLE_ADDR 0xFC400000
44 #define HW_MAP_ADDR 0xFE000000
45 #define HW_MAP_MAX 0xFFEF0000
46 #define NUM_HW_PAGES ((HW_MAP_MAX-HW_MAP_ADDR)/0x1000)
47 #define TEMP_MAP_ADDR 0xFFEF0000 // Allows 16 "temp" pages
48 #define NUM_TEMP_PAGES 16
49 #define LAST_BLOCK_ADDR 0xFFFF0000 // Free space for kernel provided user code/ *(-1) protection
51 #define PF_PRESENT 0x1
54 #define PF_GLOBAL 0x80
56 #define PF_NOPAGE 0x400
58 #define INVLPG(addr) __asm__ __volatile__ ("invlpg (%0)"::"r"(addr))
60 typedef Uint32 tTabEnt;
63 extern char _UsertextEnd[], _UsertextBase[];
64 extern Uint32 gaInitPageDir[1024];
65 extern Uint32 gaInitPageTable[1024];
66 extern void Threads_SegFault(tVAddr Addr);
67 extern void Error_Backtrace(Uint eip, Uint ebp);
70 void MM_PreinitVirtual(void);
71 void MM_InstallVirtual(void);
72 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
73 //void MM_DumpTables(tVAddr Start, tVAddr End);
74 //void MM_ClearUser(void);
75 tPAddr MM_DuplicatePage(tVAddr VAddr);
78 #define gaPageTable ((tTabEnt*)PAGE_TABLE_ADDR)
79 #define gaPageDir ((tTabEnt*)PAGE_DIR_ADDR)
80 #define gaTmpTable ((tTabEnt*)TMP_TABLE_ADDR)
81 #define gaTmpDir ((tTabEnt*)TMP_DIR_ADDR)
82 #define gpPageCR3 ((tTabEnt*)PAGE_CR3_ADDR)
83 #define gpTmpCR3 ((tTabEnt*)TMP_CR3_ADDR)
85 #define gaPAE_PageTable ((tTabEnt*)PAE_PAGE_TABLE_ADDR)
86 #define gaPAE_PageDir ((tTabEnt*)PAE_PAGE_DIR_ADDR)
87 #define gaPAE_MainPDPT ((tTabEnt*)PAE_PAGE_PDPT_ADDR)
88 #define gaPAE_TmpTable ((tTabEnt*)PAE_TMP_DIR_ADDR)
89 #define gaPAE_TmpDir ((tTabEnt*)PAE_TMP_DIR_ADDR)
90 #define gaPAE_TmpPDPT ((tTabEnt*)PAE_TMP_PDPT_ADDR)
92 tMutex glTempMappings;
94 Uint32 gWorkerStacks[(NUM_WORKER_STACKS+31)/32];
95 int giLastUsedWorker = 0;
102 } *gaMappedRegions; // sizeof = 24 bytes
106 * \fn void MM_PreinitVirtual(void)
107 * \brief Maps the fractal mappings
109 void MM_PreinitVirtual(void)
111 gaInitPageDir[ PAGE_TABLE_ADDR >> 22 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
112 INVLPG( PAGE_TABLE_ADDR );
116 * \fn void MM_InstallVirtual(void)
117 * \brief Sets up the constant page mappings
119 void MM_InstallVirtual(void)
123 // --- Pre-Allocate kernel tables
124 for( i = KERNEL_BASE>>22; i < 1024; i ++ )
126 if( gaPageDir[ i ] ) continue;
127 // Skip stack tables, they are process unique
128 if( i > KERNEL_STACKS >> 22 && i < KERNEL_STACKS_END >> 22) {
133 gaPageDir[ i ] = MM_AllocPhys() | 3;
134 INVLPG( &gaPageTable[i*1024] );
135 memset( &gaPageTable[i*1024], 0, 0x1000 );
138 // Unset kernel on the User Text pages
139 for( i = ((tVAddr)&_UsertextEnd-(tVAddr)&_UsertextBase+0xFFF)/4096; i--; ) {
140 MM_SetFlags( (tVAddr)&_UsertextBase + i*4096, 0, MM_PFLAG_KERNEL );
145 * \brief Cleans up the SMP required mappings
147 void MM_FinishVirtualInit(void)
149 gaInitPageDir[ 0 ] = 0;
153 * \fn void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
154 * \brief Called on a page fault
156 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
158 //ENTER("xAddr bErrorCode", Addr, ErrorCode);
160 // -- Check for COW --
161 if( gaPageDir [Addr>>22] & PF_PRESENT && gaPageTable[Addr>>12] & PF_PRESENT
162 && gaPageTable[Addr>>12] & PF_COW )
165 if(MM_GetRefCount( gaPageTable[Addr>>12] & ~0xFFF ) == 1)
167 gaPageTable[Addr>>12] &= ~PF_COW;
168 gaPageTable[Addr>>12] |= PF_PRESENT|PF_WRITE;
172 //Log("MM_PageFault: COW - MM_DuplicatePage(0x%x)", Addr);
173 paddr = MM_DuplicatePage( Addr );
174 MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF );
175 gaPageTable[Addr>>12] &= PF_USER;
176 gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE;
179 // Log_Debug("MMVirt", "COW for %p (%P)", Addr, gaPageTable[Addr>>12]);
181 INVLPG( Addr & ~0xFFF );
185 __asm__ __volatile__ ("pushf; andw $0xFEFF, 0(%esp); popf");
186 Proc_GetCurThread()->bInstrTrace = 0;
188 // If it was a user, tell the thread handler
190 Log_Warning("MMVirt", "User %s %s memory%s",
191 (ErrorCode&2?"write to":"read from"),
192 (ErrorCode&1?"bad/locked":"non-present"),
193 (ErrorCode&16?" (Instruction Fetch)":"")
195 Log_Warning("MMVirt", "Instruction %04x:%08x accessed %p", Regs->cs, Regs->eip, Addr);
196 __asm__ __volatile__ ("sti"); // Restart IRQs
198 Error_Backtrace(Regs->eip, Regs->ebp);
200 Threads_SegFault(Addr);
206 // -- Check Error Code --
208 Warning("Reserved Bits Trashed!");
211 Warning("Kernel %s %s memory%s",
212 (ErrorCode&2?"write to":"read from"),
213 (ErrorCode&1?"bad/locked":"non-present"),
214 (ErrorCode&16?" (Instruction Fetch)":"")
218 Log("Code at %p accessed %p", Regs->eip, Addr);
219 // Print Stack Backtrace
220 Error_Backtrace(Regs->eip, Regs->ebp);
222 Log("gaPageDir[0x%x] = 0x%x", Addr>>22, gaPageDir[Addr>>22]);
223 if( gaPageDir[Addr>>22] & PF_PRESENT )
224 Log("gaPageTable[0x%x] = 0x%x", Addr>>12, gaPageTable[Addr>>12]);
226 //MM_DumpTables(0, -1);
229 Log("EAX %08x ECX %08x EDX %08x EBX %08x", Regs->eax, Regs->ecx, Regs->edx, Regs->ebx);
230 Log("ESP %08x EBP %08x ESI %08x EDI %08x", Regs->esp, Regs->ebp, Regs->esi, Regs->edi);
231 //Log("SS:ESP %04x:%08x", Regs->ss, Regs->esp);
232 Log("CS:EIP %04x:%08x", Regs->cs, Regs->eip);
233 Log("DS %04x ES %04x FS %04x GS %04x", Regs->ds, Regs->es, Regs->fs, Regs->gs);
236 __ASM__ ("mov %%dr0, %0":"=r"(dr0):);
237 __ASM__ ("mov %%dr1, %0":"=r"(dr1):);
238 Log("DR0 %08x DR1 %08x", dr0, dr1);
241 Panic("Page Fault at 0x%x (Accessed 0x%x)", Regs->eip, Addr);
245 * \fn void MM_DumpTables(tVAddr Start, tVAddr End)
246 * \brief Dumps the layout of the page tables
248 void MM_DumpTables(tVAddr Start, tVAddr End)
250 tVAddr rangeStart = 0;
252 void *expected_node = NULL, *tmpnode = NULL;
255 const tPAddr MASK = ~0xF78;
257 Start >>= 12; End >>= 12;
260 Log("Directory Entries:");
261 for(page = Start >> 10;
262 page < (End >> 10)+1;
267 Log(" 0x%08x-0x%08x :: 0x%08x",
268 page<<22, ((page+1)<<22)-1,
269 gaPageDir[page]&~0xFFF
275 Log("Table Entries:");
276 for(page = Start, curPos = Start<<12;
278 curPos += 0x1000, page++)
280 if( !(gaPageDir[curPos>>22] & PF_PRESENT)
281 || !(gaPageTable[page] & PF_PRESENT)
282 || (gaPageTable[page] & MASK) != expected
283 || (tmpnode=NULL,MM_GetPageNode(expected, &tmpnode), tmpnode != expected_node))
286 tPAddr orig = gaPageTable[rangeStart>>12];
287 Log(" 0x%08x => 0x%08x - 0x%08x (%s%s%s%s%s) %p",
291 (orig & PF_NOPAGE ? "P" : "-"),
292 (orig & PF_COW ? "C" : "-"),
293 (orig & PF_GLOBAL ? "G" : "-"),
294 (orig & PF_USER ? "U" : "-"),
295 (orig & PF_WRITE ? "W" : "-"),
300 if( !(gaPageDir[curPos>>22] & PF_PRESENT) ) continue;
301 if( !(gaPageTable[curPos>>12] & PF_PRESENT) ) continue;
303 expected = (gaPageTable[page] & MASK);
304 MM_GetPageNode(expected, &expected_node);
307 if(expected) expected += 0x1000;
311 tPAddr orig = gaPageTable[rangeStart>>12];
312 Log("0x%08x => 0x%08x - 0x%08x (%s%s%s%s%s) %p",
316 (orig & PF_NOPAGE ? "p" : "-"),
317 (orig & PF_COW ? "C" : "-"),
318 (orig & PF_GLOBAL ? "G" : "-"),
319 (orig & PF_USER ? "U" : "-"),
320 (orig & 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();
341 Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
345 // Map and mark as user (if needed)
346 gaPageDir[ VAddr >> 22 ] = paddr | 3;
347 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
349 INVLPG( &gaPageDir[ VAddr >> 22 ] );
350 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
352 // Check if the page is already allocated
353 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
354 Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
355 //LEAVE('X', gaPageTable[ VAddr >> 12 ] & ~0xFFF);
356 return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
360 paddr = MM_AllocPhys();
361 //LOG("paddr = 0x%llx", paddr);
363 Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)",
364 VAddr, __builtin_return_address(0));
369 gaPageTable[ VAddr >> 12 ] = paddr | 3;
371 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
372 // Invalidate Cache for address
373 INVLPG( VAddr & ~0xFFF );
380 * \fn void MM_Deallocate(tVAddr VAddr)
382 void MM_Deallocate(tVAddr VAddr)
384 if( gaPageDir[ VAddr >> 22 ] == 0 ) {
385 Warning("MM_Deallocate - Directory not mapped");
389 if(gaPageTable[ VAddr >> 12 ] == 0) {
390 Warning("MM_Deallocate - Page is not allocated");
395 MM_DerefPhys( gaPageTable[ VAddr >> 12 ] & ~0xFFF );
397 gaPageTable[ VAddr >> 12 ] = 0;
401 * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
402 * \brief Checks if the passed address is accesable
404 tPAddr MM_GetPhysAddr(tVAddr Addr)
406 if( !(gaPageDir[Addr >> 22] & 1) )
408 if( !(gaPageTable[Addr >> 12] & 1) )
410 return (gaPageTable[Addr >> 12] & ~0xFFF) | (Addr & 0xFFF);
414 * \fn void MM_SetCR3(Uint CR3)
415 * \brief Sets the current process space
417 void MM_SetCR3(Uint CR3)
419 __asm__ __volatile__ ("mov %0, %%cr3"::"r"(CR3));
423 * \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
424 * \brief Map a physical page to a virtual one
426 int MM_Map(tVAddr VAddr, tPAddr PAddr)
428 //ENTER("xVAddr xPAddr", VAddr, PAddr);
430 if( PAddr & 0xFFF || VAddr & 0xFFF ) {
431 Warning("MM_Map - Physical or Virtual Addresses are not aligned");
437 PAddr &= ~0xFFF; VAddr &= ~0xFFF;
439 // Check if the directory is mapped
440 if( gaPageDir[ VAddr >> 22 ] == 0 )
442 tPAddr tmp = MM_AllocPhys();
445 gaPageDir[ VAddr >> 22 ] = tmp | 3;
448 if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
450 INVLPG( &gaPageTable[ (VAddr >> 12) & ~0x3FF ] );
451 memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
453 // Check if the page is already allocated
454 else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
455 Warning("MM_Map - Allocating to used address");
461 gaPageTable[ VAddr >> 12 ] = PAddr | 3;
463 if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
465 //LOG("gaPageTable[ 0x%x ] = (Uint)%p = 0x%x",
466 // VAddr >> 12, &gaPageTable[ VAddr >> 12 ], gaPageTable[ VAddr >> 12 ]);
471 //LOG("INVLPG( 0x%x )", VAddr);
479 * \brief Clear user's address space
481 void MM_ClearUser(void)
485 for( i = 0; i < (MM_USER_MAX>>22); i ++ )
487 // Check if directory is not allocated
488 if( !(gaPageDir[i] & PF_PRESENT) ) {
494 for( j = 0; j < 1024; j ++ )
496 if( gaPageTable[i*1024+j] & 1 )
497 MM_DerefPhys( gaPageTable[i*1024+j] & ~0xFFF );
498 gaPageTable[i*1024+j] = 0;
501 // Deallocate directory
502 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
504 INVLPG( &gaPageTable[i*1024] );
510 * \fn tPAddr MM_Clone(void)
511 * \brief Clone the current address space
513 tPAddr MM_Clone(void)
518 tVAddr kStackBase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
521 Mutex_Acquire( &glTempFractal );
523 // Create Directory Table
524 *gpTmpCR3 = MM_AllocPhys() | 3;
525 if( *gpTmpCR3 == 3 ) {
530 //LOG("Allocated Directory (%x)", *gpTmpCR3);
531 memsetd( gaTmpDir, 0, 1024 );
533 if( Threads_GetPID() != 0 )
536 for( i = 0; i < 768; i ++)
538 // Check if table is allocated
539 if( !(gaPageDir[i] & PF_PRESENT) ) {
545 // Allocate new table
546 gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
547 INVLPG( &gaTmpTable[page] );
549 for( j = 0; j < 1024; j ++, page++ )
551 if( !(gaPageTable[page] & PF_PRESENT) ) {
552 gaTmpTable[page] = 0;
557 MM_RefPhys( gaPageTable[page] & ~0xFFF );
559 if(gaPageTable[page] & PF_WRITE) {
560 gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
561 gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
562 INVLPG( page << 12 );
565 gaTmpTable[page] = gaPageTable[page];
570 // Map in kernel tables (and make fractal mapping)
571 for( i = 768; i < 1024; i ++ )
574 if( i == (PAGE_TABLE_ADDR >> 22) ) {
575 gaTmpDir[ PAGE_TABLE_ADDR >> 22 ] = *gpTmpCR3;
579 if( gaPageDir[i] == 0 ) {
584 //LOG("gaPageDir[%x/4] = 0x%x", i*4, gaPageDir[i]);
585 MM_RefPhys( gaPageDir[i] & ~0xFFF );
586 gaTmpDir[i] = gaPageDir[i];
589 // Allocate kernel stack
590 for(i = KERNEL_STACKS >> 22;
591 i < KERNEL_STACKS_END >> 22;
594 // Check if directory is allocated
595 if( (gaPageDir[i] & 1) == 0 ) {
600 // We don't care about other kernel stacks, just the current one
601 if( i != kStackBase >> 22 ) {
602 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
608 gaTmpDir[i] = MM_AllocPhys() | 3;
609 INVLPG( &gaTmpTable[i*1024] );
610 for( j = 0; j < 1024; j ++ )
612 // Is the page allocated? If not, skip
613 if( !(gaPageTable[i*1024+j] & 1) ) {
614 gaTmpTable[i*1024+j] = 0;
618 // We don't care about other kernel stacks
619 if( ((i*1024+j)*4096 & ~(KERNEL_STACK_SIZE-1)) != kStackBase ) {
620 gaTmpTable[i*1024+j] = 0;
625 gaTmpTable[i*1024+j] = MM_AllocPhys() | 3;
627 MM_RefPhys( gaTmpTable[i*1024+j] & ~0xFFF );
629 tmp = (void *) MM_MapTemp( gaTmpTable[i*1024+j] & ~0xFFF );
630 memcpy( tmp, (void *)( (i*1024+j)*0x1000 ), 0x1000 );
631 MM_FreeTemp( (Uint)tmp );
635 ret = *gpTmpCR3 & ~0xFFF;
636 Mutex_Release( &glTempFractal );
643 * \fn tVAddr MM_NewKStack(void)
644 * \brief Create a new kernel stack
646 tVAddr MM_NewKStack(void)
650 for(base = KERNEL_STACKS; base < KERNEL_STACKS_END; base += KERNEL_STACK_SIZE)
652 // Check if space is free
653 if(MM_GetPhysAddr(base) != 0) continue;
655 //for(i = KERNEL_STACK_SIZE; i -= 0x1000 ; )
656 for(i = 0; i < KERNEL_STACK_SIZE; i += 0x1000 )
658 if( MM_Allocate(base+i) == 0 )
660 // On error, print a warning and return error
661 Warning("MM_NewKStack - Out of memory");
663 //for( i += 0x1000 ; i < KERNEL_STACK_SIZE; i += 0x1000 )
664 // MM_Deallocate(base+i);
669 Log("MM_NewKStack - Allocated %p", base + KERNEL_STACK_SIZE);
670 return base+KERNEL_STACK_SIZE;
673 Warning("MM_NewKStack - No address space left");
678 * \fn tVAddr MM_NewWorkerStack()
679 * \brief Creates a new worker stack
681 tVAddr MM_NewWorkerStack(Uint *StackContents, size_t ContentsSize)
687 // TODO: Thread safety
688 // Find a free worker stack address
689 for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
692 if( gWorkerStacks[base/32] == -1 ) {
693 base += 31; base &= ~31;
694 base --; // Counteracted by the base++
698 if( gWorkerStacks[base/32] & (1 << base) ) {
703 if(base >= NUM_WORKER_STACKS) {
704 Warning("Uh-oh! Out of worker stacks");
709 gWorkerStacks[base/32] |= (1 << base);
710 // Make life easier for later calls
711 giLastUsedWorker = base;
713 base = WORKER_STACKS + base * WORKER_STACK_SIZE;
714 //Log(" MM_NewWorkerStack: base = 0x%x", base);
716 // Acquire the lock for the temp fractal mappings
717 Mutex_Acquire(&glTempFractal);
719 // Set the temp fractals to TID0's address space
720 *gpTmpCR3 = ((Uint)gaInitPageDir - KERNEL_BASE) | 3;
721 //Log(" MM_NewWorkerStack: *gpTmpCR3 = 0x%x", *gpTmpCR3);
725 // Check if the directory is mapped (we are assuming that the stacks
726 // will fit neatly in a directory)
727 //Log(" MM_NewWorkerStack: gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
728 if(gaTmpDir[ base >> 22 ] == 0) {
729 gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
730 INVLPG( &gaTmpTable[ (base>>12) & ~0x3FF ] );
734 for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
736 page = MM_AllocPhys();
737 gaTmpTable[ (base + addr) >> 12 ] = page | 3;
740 // Release the temp mapping lock
741 Mutex_Release(&glTempFractal);
743 // NOTE: Max of 1 page
744 // `page` is the last allocated page from the previious for loop
745 tmpPage = MM_MapTemp( page );
746 memcpy( (void*)( tmpPage + (0x1000 - ContentsSize) ), StackContents, ContentsSize);
747 MM_FreeTemp(tmpPage);
749 //Log("MM_NewWorkerStack: RETURN 0x%x", base);
750 return base + WORKER_STACK_SIZE;
754 * \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
755 * \brief Sets the flags on a page
757 void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
760 if( !(gaPageDir[VAddr >> 22] & 1) ) return ;
761 if( !(gaPageTable[VAddr >> 12] & 1) ) return ;
763 ent = &gaPageTable[VAddr >> 12];
766 if( Mask & MM_PFLAG_RO )
768 if( Flags & MM_PFLAG_RO ) {
772 gaPageDir[VAddr >> 22] |= PF_WRITE;
778 if( Mask & MM_PFLAG_KERNEL )
780 if( Flags & MM_PFLAG_KERNEL ) {
784 gaPageDir[VAddr >> 22] |= PF_USER;
790 if( Mask & MM_PFLAG_COW )
792 if( Flags & MM_PFLAG_COW ) {
802 //Log("MM_SetFlags: *ent = 0x%08x, gaPageDir[%i] = 0x%08x",
803 // *ent, VAddr >> 22, gaPageDir[VAddr >> 22]);
807 * \brief Get the flags on a page
809 Uint MM_GetFlags(tVAddr VAddr)
815 if( !(gaPageDir[VAddr >> 22] & 1) ) return 0;
816 if( !(gaPageTable[VAddr >> 12] & 1) ) return 0;
818 ent = &gaPageTable[VAddr >> 12];
821 if( !(*ent & PF_WRITE) ) ret |= MM_PFLAG_RO;
823 if( !(*ent & PF_USER) ) ret |= MM_PFLAG_KERNEL;
825 if( *ent & PF_COW ) ret |= MM_PFLAG_COW;
831 * \brief Check if the provided buffer is valid
832 * \return Boolean valid
834 int MM_IsValidBuffer(tVAddr Addr, size_t Size)
839 Size += Addr & (PAGE_SIZE-1);
840 Addr &= ~(PAGE_SIZE-1);
845 // Debug("Addr = %p, Size = 0x%x, dir = %i, tab = %i", Addr, Size, dir, tab);
847 if( !(gaPageDir[dir] & 1) ) return 0;
848 if( !(gaPageTable[tab] & 1) ) return 0;
850 bIsUser = !!(gaPageTable[tab] & PF_USER);
852 while( Size >= PAGE_SIZE )
854 if( (tab & 1023) == 0 )
857 if( !(gaPageDir[dir] & 1) ) return 0;
860 if( !(gaPageTable[tab] & 1) ) return 0;
861 if( bIsUser && !(gaPageTable[tab] & PF_USER) ) return 0;
870 * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
871 * \brief Duplicates a virtual page to a physical one
873 tPAddr MM_DuplicatePage(tVAddr VAddr)
879 //ENTER("xVAddr", VAddr);
882 if( !(gaPageDir [VAddr >> 22] & PF_PRESENT) ) return 0;
883 if( !(gaPageTable[VAddr >> 12] & PF_PRESENT) ) return 0;
889 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();
1034 ret = MM_MapHWPages(phys, 1);
1045 phys = MM_AllocPhysRange(Pages, MaxBits);
1046 // - Was it allocated?
1052 // Allocated successfully, now map
1053 ret = MM_MapHWPages(phys, Pages);
1055 // If it didn't map, free then return 0
1056 for(;Pages--;phys+=0x1000)
1068 * \fn void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1069 * \brief Unmap a hardware page
1071 void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1075 //Log_Debug("VirtMem", "MM_UnmapHWPages: (VAddr=0x%08x, Number=%i)", VAddr, Number);
1078 if(VAddr < HW_MAP_ADDR || VAddr+Number*0x1000 > HW_MAP_MAX) return;
1082 Mutex_Acquire( &glTempMappings ); // Temp and HW share a directory, so they share a lock
1084 for( j = 0; j < Number; j++ )
1086 MM_DerefPhys( gaPageTable[ i + j ] & ~0xFFF );
1087 gaPageTable[ i + j ] = 0;
1090 Mutex_Release( &glTempMappings );