2 * AcessOS Microkernel Version
10 * 0xFF - System Calls / Kernel's User Code
20 #include <semaphore.h>
22 #include "include/vmem_layout.h"
28 #define PF_PRESENT 0x1
31 #define PF_GLOBAL 0x80
33 #define PF_NOPAGE 0x400
35 #define INVLPG(addr) __asm__ __volatile__ ("invlpg (%0)"::"r"(addr))
37 #define GET_TEMP_MAPPING(cr3) do { \
39 __AtomicTestSetLoop( (Uint *)gpTmpCR3, cr3 | 3 ); \
41 #define REL_TEMP_MAPPING() do { \
46 typedef Uint32 tTabEnt;
49 extern tPage _UsertextEnd;
50 extern tPage _UsertextBase;
51 extern tPage gKernelEnd; // defined as page aligned
52 extern Uint32 gaInitPageDir[1024];
53 extern Uint32 gaInitPageTable[1024];
54 extern void Threads_SegFault(tVAddr Addr);
57 void MM_PreinitVirtual(void);
58 void MM_InstallVirtual(void);
59 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
60 void MM_DumpTables_Print(tVAddr Start, Uint32 Orig, size_t Size, void *Node);
61 //void MM_DumpTables(tVAddr Start, tVAddr End);
62 //void MM_ClearUser(void);
63 tPAddr MM_DuplicatePage(tVAddr VAddr);
66 #define gaPageTable ((tTabEnt*)PAGE_TABLE_ADDR)
67 #define gaPageDir ((tTabEnt*)PAGE_DIR_ADDR)
68 #define gaTmpTable ((tTabEnt*)TMP_TABLE_ADDR)
69 #define gaTmpDir ((tTabEnt*)TMP_DIR_ADDR)
70 #define gpPageCR3 ((tTabEnt*)PAGE_CR3_ADDR)
71 #define gpTmpCR3 ((tTabEnt*)TMP_CR3_ADDR)
73 #define gaPAE_PageTable ((tTabEnt*)PAE_PAGE_TABLE_ADDR)
74 #define gaPAE_PageDir ((tTabEnt*)PAE_PAGE_DIR_ADDR)
75 #define gaPAE_MainPDPT ((tTabEnt*)PAE_PAGE_PDPT_ADDR)
76 #define gaPAE_TmpTable ((tTabEnt*)PAE_TMP_DIR_ADDR)
77 #define gaPAE_TmpDir ((tTabEnt*)PAE_TMP_DIR_ADDR)
78 #define gaPAE_TmpPDPT ((tTabEnt*)PAE_TMP_PDPT_ADDR)
80 tMutex glTempMappings;
81 tSemaphore gTempMappingsSem;
83 Uint32 gWorkerStacks[(NUM_WORKER_STACKS+31)/32];
84 int giLastUsedWorker = 0;
91 } *gaMappedRegions; // sizeof = 24 bytes
93 tShortSpinlock glMM_ZeroPage;
98 * \fn void MM_PreinitVirtual(void)
99 * \brief Maps the fractal mappings
101 void MM_PreinitVirtual(void)
103 gaInitPageDir[ PAGE_TABLE_ADDR >> 22 ] = ((tTabEnt)&gaInitPageDir - KERNEL_BASE) | 3;
104 INVLPG( PAGE_TABLE_ADDR );
106 Semaphore_Init(&gTempMappingsSem, NUM_TEMP_PAGES, NUM_TEMP_PAGES, "MMVirt", "Temp Mappings");
110 * \fn void MM_InstallVirtual(void)
111 * \brief Sets up the constant page mappings
113 void MM_InstallVirtual(void)
115 // Don't bother referencing, as it'a in the kernel area
116 //MM_RefPhys( gaInitPageDir[ PAGE_TABLE_ADDR >> 22 ] );
117 // --- Pre-Allocate kernel tables
118 for( int i = KERNEL_BASE>>22; i < 1024; i ++ )
120 if( gaPageDir[ i ] ) {
121 // MM_RefPhys( gaPageDir[ i ] & ~0xFFF );
124 // Skip stack tables, they are process unique
125 if( i > MM_KERNEL_STACKS >> 22 && i < MM_KERNEL_STACKS_END >> 22) {
130 gaPageDir[ i ] = MM_AllocPhys() | 3;
131 INVLPG( &gaPageTable[i*1024] );
132 memset( &gaPageTable[i*1024], 0, 0x1000 );
135 // Unset kernel on the User Text pages
136 ASSERT( ((tVAddr)&_UsertextBase & (PAGE_SIZE-1)) == 0 );
137 //ASSERT( ((tVAddr)&_UsertextEnd & (PAGE_SIZE-1)) == 0 );
138 for( tPage *page = &_UsertextBase; page < &_UsertextEnd; page ++ )
140 MM_SetFlags( page, 0, MM_PFLAG_KERNEL );
143 // Unmap the area between end of kernel image and the heap
144 // DISABLED: Assumptions in main.c
146 for( tPage *page = &gKernelEnd; page < (tPage*)(KERNEL_BASE+4*1024*1024); page ++ )
148 gaPageTable[ (tVAddr)page / PAGE_SIZE ] = 0;
149 //MM_Deallocate(page);
157 * \brief Cleans up the SMP required mappings
159 void MM_FinishVirtualInit(void)
161 gaInitPageDir[ 0 ] = 0;
165 * \fn void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
166 * \brief Called on a page fault
168 void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
170 //ENTER("xAddr bErrorCode", Addr, ErrorCode);
172 // -- Check for COW --
173 if( gaPageDir [Addr>>22] & PF_PRESENT && gaPageTable[Addr>>12] & PF_PRESENT
174 && gaPageTable[Addr>>12] & PF_COW )
177 __asm__ __volatile__ ("sti");
178 if(MM_GetRefCount( gaPageTable[Addr>>12] & ~0xFFF ) == 1)
180 gaPageTable[Addr>>12] &= ~PF_COW;
181 gaPageTable[Addr>>12] |= PF_PRESENT|PF_WRITE;
185 //Log("MM_PageFault: COW - MM_DuplicatePage(0x%x)", Addr);
186 paddr = MM_DuplicatePage( Addr );
187 MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF );
188 gaPageTable[Addr>>12] &= PF_USER;
189 gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE;
192 // Log_Debug("MMVirt", "COW for %p (%P)", Addr, gaPageTable[Addr>>12]);
194 INVLPG( Addr & ~0xFFF );
198 // Disable instruction tracing
199 __ASM__("pushf; andw $0xFEFF, 0(%esp); popf");
200 Proc_GetCurThread()->bInstrTrace = 0;
202 // If it was a user, tell the thread handler
204 __asm__ __volatile__ ("sti");
205 Log_Warning("MMVirt", "User %s %s memory%s",
206 (ErrorCode&2?"write to":"read from"),
207 (ErrorCode&1?"bad/locked":"non-present"),
208 (ErrorCode&16?" (Instruction Fetch)":"")
210 Log_Warning("MMVirt", "Instruction %04x:%08x accessed %p", Regs->cs, Regs->eip, Addr);
211 __ASM__("sti"); // Restart IRQs
213 Error_Backtrace(Regs->eip, Regs->ebp);
215 Threads_SegFault(Addr);
221 // -- Check Error Code --
223 Warning("Reserved Bits Trashed!");
226 Warning("Kernel %s %s memory%s",
227 (ErrorCode&2?"write to":"read from"),
228 (ErrorCode&1?"bad/locked":"non-present"),
229 (ErrorCode&16?" (Instruction Fetch)":"")
233 Log("CPU %i - Code at %p accessed %p", GetCPUNum(), Regs->eip, Addr);
234 // Print Stack Backtrace
235 Error_Backtrace(Regs->eip, Regs->ebp);
238 Log("gaPageDir[0x%x] = 0x%x", Addr>>22, gaPageDir[Addr>>22]);
239 if( gaPageDir[Addr>>22] & PF_PRESENT )
240 Log("gaPageTable[0x%x] = 0x%x", Addr>>12, gaPageTable[Addr>>12]);
242 //MM_DumpTables(0, -1);
245 Log("EAX %08x ECX %08x EDX %08x EBX %08x", Regs->eax, Regs->ecx, Regs->edx, Regs->ebx);
246 Log("ESP %08x EBP %08x ESI %08x EDI %08x", Regs->esp, Regs->ebp, Regs->esi, Regs->edi);
247 //Log("SS:ESP %04x:%08x", Regs->ss, Regs->esp);
248 Log("CS:EIP %04x:%08x", Regs->cs, Regs->eip);
249 Log("DS %04x ES %04x FS %04x GS %04x", Regs->ds, Regs->es, Regs->fs, Regs->gs);
252 __ASM__ ("mov %%dr0, %0":"=r"(dr0):);
253 __ASM__ ("mov %%dr1, %0":"=r"(dr1):);
254 Log("DR0 %08x DR1 %08x", dr0, dr1);
257 Panic("Page Fault at 0x%x (Accessed 0x%x)", Regs->eip, Addr);
260 void MM_DumpTables_Print(tVAddr Start, Uint32 Orig, size_t Size, void *Node)
262 if( (Orig & ~(PAGE_SIZE-1)) == giMM_ZeroPage )
264 Log( "0x%08x => ZERO + 0x%08x (%s%s%s%s%s) %p",
267 (Orig & PF_NOPAGE ? "P" : "-"),
268 (Orig & PF_COW ? "C" : "-"),
269 (Orig & PF_GLOBAL ? "G" : "-"),
270 (Orig & PF_USER ? "U" : "-"),
271 (Orig & PF_WRITE ? "W" : "-"),
277 Log(" 0x%08x => 0x%08x + 0x%08x (%s%s%s%s%s) %p",
281 (Orig & PF_NOPAGE ? "P" : "-"),
282 (Orig & PF_COW ? "C" : "-"),
283 (Orig & PF_GLOBAL ? "G" : "-"),
284 (Orig & PF_USER ? "U" : "-"),
285 (Orig & PF_WRITE ? "W" : "-"),
292 * \fn void MM_DumpTables(tVAddr Start, tVAddr End)
293 * \brief Dumps the layout of the page tables
295 void MM_DumpTables(tVAddr Start, tVAddr End)
297 tVAddr rangeStart = 0;
299 void *expected_node = NULL, *tmpnode = NULL;
302 const tPAddr MASK = ~0xF78;
304 Start >>= 12; End >>= 12;
307 Log("Directory Entries:");
308 for(page = Start >> 10;
309 page < (End >> 10)+1;
314 Log(" 0x%08x-0x%08x :: 0x%08x",
315 page<<22, ((page+1)<<22)-1,
316 gaPageDir[page]&~0xFFF
322 Log("Table Entries:");
323 for(page = Start, curPos = Start<<12;
325 curPos += 0x1000, page++)
327 if( !(gaPageDir[curPos>>22] & PF_PRESENT)
328 || !(gaPageTable[page] & PF_PRESENT)
329 || (gaPageTable[page] & MASK) != expected
330 || (tmpnode=NULL,MM_GetPageNode(expected, &tmpnode), tmpnode != expected_node))
333 tPAddr orig = gaPageTable[rangeStart>>12];
334 MM_DumpTables_Print(rangeStart, orig, curPos - rangeStart, expected_node);
337 if( !(gaPageDir[curPos>>22] & PF_PRESENT) ) continue;
338 if( !(gaPageTable[curPos>>12] & PF_PRESENT) ) continue;
340 expected = (gaPageTable[page] & MASK);
341 MM_GetPageNode(expected, &expected_node);
344 if(expected && (expected & ~(PAGE_SIZE-1)) != giMM_ZeroPage)
349 tPAddr orig = gaPageTable[rangeStart>>12];
350 MM_DumpTables_Print(rangeStart, orig, curPos - rangeStart, expected_node);
356 * \fn tPAddr MM_Allocate(tVAddr VAddr)
358 tPAddr MM_Allocate(volatile void * VAddr)
360 tPAddr paddr = MM_AllocPhys();
361 if( MM_Map(VAddr, paddr) )
366 // Error of some form, either an overwrite or OOM
369 // Check for overwrite
370 paddr = MM_GetPhysAddr(VAddr);
372 Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
377 Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
381 void MM_AllocateZero(volatile void *VAddr)
383 if( MM_GetPhysAddr(VAddr) ) {
384 Warning("MM_AllocateZero - Attempted overwrite at %p", VAddr);
389 SHORTLOCK(&glMM_ZeroPage);
390 // Check again within the lock (just in case we lost the race)
391 if( giMM_ZeroPage == 0 )
393 giMM_ZeroPage = MM_Allocate(VAddr);
394 // - Reference a second time to prevent it from being freed
395 MM_RefPhys(giMM_ZeroPage);
396 memset((void*)VAddr, 0, PAGE_SIZE);
398 SHORTREL(&glMM_ZeroPage);
402 MM_Map(VAddr, giMM_ZeroPage);
403 MM_RefPhys(giMM_ZeroPage);
405 MM_SetFlags(VAddr, MM_PFLAG_COW, MM_PFLAG_COW);
409 * \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
410 * \brief Map a physical page to a virtual one
412 int MM_Map(volatile void *VAddr, tPAddr PAddr)
414 Uint pagenum = (tVAddr)VAddr >> 12;
417 Debug("MM_Map(%p, %P)", VAddr, PAddr);
421 if( (PAddr & 0xFFF) || ((tVAddr)VAddr & 0xFFF) ) {
422 Log_Warning("MM_Virt", "MM_Map - Physical or Virtual Addresses are not aligned (%P and %p) - %p",
423 PAddr, VAddr, __builtin_return_address(0));
428 bool is_user = ((tVAddr)VAddr < MM_USER_MAX);
430 // Check if the directory is mapped
431 if( gaPageDir[ pagenum >> 10 ] == 0 )
433 tPAddr tmp = MM_AllocPhys();
436 gaPageDir[ pagenum >> 10 ] = tmp | 3 | (is_user ? PF_USER : 0);
438 INVLPG( &gaPageTable[ pagenum & ~0x3FF ] );
439 memsetd( &gaPageTable[ pagenum & ~0x3FF ], 0, 1024 );
441 // Check if the page is already allocated
442 else if( gaPageTable[ pagenum ] != 0 ) {
443 Warning("MM_Map - Allocating to used address");
449 gaPageTable[ pagenum ] = PAddr | 3 | (is_user ? PF_USER : 0);
459 void MM_Deallocate(volatile void *VAddr)
461 Uint pagenum = (tVAddr)VAddr >> 12;
462 if( gaPageDir[pagenum>>10] == 0 ) {
463 Warning("MM_Deallocate - Directory not mapped");
467 if(gaPageTable[pagenum] == 0) {
468 Warning("MM_Deallocate - Page is not allocated");
472 // Dereference and clear page
473 tPAddr paddr = gaPageTable[pagenum] & ~0xFFF;
474 gaPageTable[pagenum] = 0;
475 MM_DerefPhys( paddr );
479 * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
480 * \brief Checks if the passed address is accesable
482 tPAddr MM_GetPhysAddr(volatile const void *Addr)
484 tVAddr addr = (tVAddr)Addr;
485 if( !(gaPageDir[addr >> 22] & 1) )
487 if( !(gaPageTable[addr >> 12] & 1) )
489 return (gaPageTable[addr >> 12] & ~0xFFF) | (addr & 0xFFF);
493 * \fn void MM_SetCR3(Uint CR3)
494 * \brief Sets the current process space
496 void MM_SetCR3(Uint CR3)
498 __ASM__("mov %0, %%cr3"::"r"(CR3));
502 * \brief Clear user's address space
504 void MM_ClearUser(void)
508 for( i = 0; i < (MM_USER_MAX>>22); i ++ )
510 // Check if directory is not allocated
511 if( !(gaPageDir[i] & PF_PRESENT) ) {
517 for( j = 0; j < 1024; j ++ )
519 if( gaPageTable[i*1024+j] & 1 )
520 MM_DerefPhys( gaPageTable[i*1024+j] & ~0xFFF );
521 gaPageTable[i*1024+j] = 0;
524 // Deallocate directory
525 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
527 INVLPG( &gaPageTable[i*1024] );
533 * \brief Deallocate an address space
535 void MM_ClearSpace(Uint32 CR3)
539 if(CR3 == (*gpPageCR3 & ~0xFFF)) {
540 Log_Error("MMVirt", "Can't clear current address space");
544 if( MM_GetRefCount(CR3) > 1 ) {
546 Log_Log("MMVirt", "CR3 %P is still referenced, not cleaning (but dereferenced)", CR3);
550 Log_Debug("MMVirt", "Clearing out address space 0x%x from 0x%x", CR3, *gpPageCR3);
552 GET_TEMP_MAPPING(CR3);
555 for( i = 0; i < 1024; i ++ )
557 Uint32 *table = &gaTmpTable[i*1024];
558 if( !(gaTmpDir[i] & PF_PRESENT) )
563 if( i < 768 || (i > MM_KERNEL_STACKS >> 22 && i < MM_KERNEL_STACKS_END >> 22) )
565 for( j = 0; j < 1024; j ++ )
567 if( !(table[j] & 1) )
569 MM_DerefPhys( table[j] & ~0xFFF );
573 if( i != (PAGE_TABLE_ADDR >> 22) )
575 MM_DerefPhys( gaTmpDir[i] & ~0xFFF );
586 * \fn tPAddr MM_Clone(void)
587 * \brief Clone the current address space
589 tPAddr MM_Clone(int bNoUserCopy)
594 tVAddr kStackBase = Proc_GetCurThread()->KernelStack - MM_KERNEL_STACK_SIZE;
596 // Create Directory Table
597 ret = MM_AllocPhys();
603 GET_TEMP_MAPPING( ret );
605 memsetd( gaTmpDir, 0, 1024 );
607 if( Threads_GetPID() != 0 && !bNoUserCopy )
610 for( i = 0; i < 768; i ++)
612 // Check if table is allocated
613 if( !(gaPageDir[i] & PF_PRESENT) ) {
619 // Allocate new table
620 gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
621 INVLPG( &gaTmpTable[page] );
623 for( j = 0; j < 1024; j ++, page++ )
625 if( !(gaPageTable[page] & PF_PRESENT) ) {
626 gaTmpTable[page] = 0;
631 MM_RefPhys( gaPageTable[page] & ~0xFFF );
633 if(gaPageTable[page] & PF_WRITE) {
634 gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
635 gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
636 INVLPG( page << 12 );
639 gaTmpTable[page] = gaPageTable[page];
644 // Map in kernel tables (and make fractal mapping)
645 for( i = 768; i < 1024; i ++ )
648 if( i == (PAGE_TABLE_ADDR >> 22) ) {
649 gaTmpDir[ PAGE_TABLE_ADDR >> 22 ] = *gpTmpCR3;
652 if( i == (TMP_TABLE_ADDR >> 22) ) {
653 gaTmpDir[ TMP_TABLE_ADDR >> 22 ] = 0;
657 if( gaPageDir[i] == 0 ) {
662 //LOG("gaPageDir[%x/4] = 0x%x", i*4, gaPageDir[i]);
663 MM_RefPhys( gaPageDir[i] & ~0xFFF );
664 gaTmpDir[i] = gaPageDir[i];
667 // Allocate kernel stack
668 for(i = MM_KERNEL_STACKS >> 22; i < MM_KERNEL_STACKS_END >> 22; i ++ )
670 // Check if directory is allocated
671 if( (gaPageDir[i] & 1) == 0 ) {
676 // We don't care about other kernel stacks, just the current one
677 if( i != kStackBase >> 22 ) {
678 MM_DerefPhys( gaPageDir[i] & ~0xFFF );
684 gaTmpDir[i] = MM_AllocPhys() | 3;
685 INVLPG( &gaTmpTable[i*1024] );
686 for( j = 0; j < 1024; j ++ )
688 // Is the page allocated? If not, skip
689 if( !(gaPageTable[i*1024+j] & 1) ) {
690 gaTmpTable[i*1024+j] = 0;
694 // We don't care about other kernel stacks
695 if( ((i*1024+j)*4096 & ~(MM_KERNEL_STACK_SIZE-1)) != kStackBase ) {
696 gaTmpTable[i*1024+j] = 0;
701 gaTmpTable[i*1024+j] = MM_AllocPhys() | 3;
703 void *tmp = MM_MapTemp( gaTmpTable[i*1024+j] & ~0xFFF );
704 memcpy( tmp, (void *)( (i*1024+j)*PAGE_SIZE ), PAGE_SIZE );
716 * \fn tVAddr MM_NewKStack(void)
717 * \brief Create a new kernel stack
719 tVAddr MM_NewKStack(void)
721 for(tVAddr base = MM_KERNEL_STACKS; base < MM_KERNEL_STACKS_END; base += MM_KERNEL_STACK_SIZE)
723 tPage *pageptr = (void*)base;
724 // Check if space is free
725 if(MM_GetPhysAddr(pageptr) != 0)
728 for(Uint i = 0; i < MM_KERNEL_STACK_SIZE/PAGE_SIZE; i ++ )
730 if( MM_Allocate(pageptr + i) == 0 )
732 // On error, print a warning and return error
733 Warning("MM_NewKStack - Out of memory");
735 //for( i += 0x1000 ; i < MM_KERNEL_STACK_SIZE; i += 0x1000 )
736 // MM_Deallocate(base+i);
741 // Log("MM_NewKStack - Allocated %p", base + MM_KERNEL_STACK_SIZE);
742 return base+MM_KERNEL_STACK_SIZE;
745 Log_Warning("MMVirt", "MM_NewKStack - No address space left");
750 * \fn tVAddr MM_NewWorkerStack()
751 * \brief Creates a new worker stack
753 tVAddr MM_NewWorkerStack(Uint *StackContents, size_t ContentsSize)
758 LOG("(StackContents=%p,ContentsSize=%i)", StackContents, ContentsSize);
759 // TODO: Thread safety
760 // Find a free worker stack address
761 for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
764 if( gWorkerStacks[base/32] == -1 ) {
765 base += 31; base &= ~31;
766 base --; // Counteracted by the base++
770 if( gWorkerStacks[base/32] & (1 << base) ) {
775 if(base >= NUM_WORKER_STACKS) {
776 Log_Error("MMVirt", "Uh-oh! Out of worker stacks");
779 LOG("base=0x%x", base);
782 gWorkerStacks[base/32] |= (1 << base);
783 // Make life easier for later calls
784 giLastUsedWorker = base;
786 base = WORKER_STACKS + base * WORKER_STACK_SIZE;
787 //Log(" MM_NewWorkerStack: base = 0x%x", base);
788 LOG("base=%p (top)", base);
790 // Set the temp fractals to TID0's address space
791 GET_TEMP_MAPPING( ((Uint)gaInitPageDir - KERNEL_BASE) );
794 // Check if the directory is mapped (we are assuming that the stacks
795 // will fit neatly in a directory)
796 LOG("gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
797 if(gaTmpDir[ base >> 22 ] == 0) {
798 gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
799 INVLPG( &gaTmpTable[ (base>>12) & ~0x3FF ] );
803 for( Uint addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
805 page = MM_AllocPhys();
806 gaTmpTable[ (base + addr) >> 12 ] = page | 3;
810 // Release temporary fractal
813 // NOTE: Max of 1 page
814 // `page` is the last allocated page from the previious for loop
815 LOG("Mapping first page");
816 char *tmpPage = MM_MapTemp( page );
817 LOG("tmpPage=%p", tmpPage);
818 memcpy( tmpPage + (0x1000 - ContentsSize), StackContents, ContentsSize);
819 MM_FreeTemp( tmpPage );
821 //Log("MM_NewWorkerStack: RETURN 0x%x", base);
822 LOG("return %p", base+WORKER_STACK_SIZE);
823 return base + WORKER_STACK_SIZE;
827 * \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
828 * \brief Sets the flags on a page
830 void MM_SetFlags(volatile void *VAddr, Uint Flags, Uint Mask)
832 Uint pagenum = (tVAddr)VAddr >> 12;
833 if( !(gaPageDir[pagenum >> 10] & 1) ) return ;
834 if( !(gaPageTable[pagenum] & 1) ) return ;
836 tTabEnt *ent = &gaPageTable[pagenum];
839 if( Mask & MM_PFLAG_RO )
841 if( Flags & MM_PFLAG_RO ) {
845 gaPageDir[pagenum >> 10] |= PF_WRITE;
851 if( Mask & MM_PFLAG_KERNEL )
853 if( Flags & MM_PFLAG_KERNEL ) {
857 gaPageDir[pagenum >> 10] |= PF_USER;
863 if( Mask & MM_PFLAG_COW )
865 if( Flags & MM_PFLAG_COW ) {
875 //Log("MM_SetFlags: *ent = 0x%08x, gaPageDir[%i] = 0x%08x",
876 // *ent, VAddr >> 22, gaPageDir[VAddr >> 22]);
880 * \brief Get the flags on a page
882 Uint MM_GetFlags(volatile const void *VAddr)
884 Uint pagenum = (tVAddr)VAddr >> 12;
887 if( !(gaPageDir[pagenum >> 10] & 1) ) return 0;
888 if( !(gaPageTable[pagenum] & 1) ) return 0;
890 tTabEnt *ent = &gaPageTable[pagenum];
894 if( !(*ent & PF_WRITE) ) ret |= MM_PFLAG_RO;
896 if( !(*ent & PF_USER) ) ret |= MM_PFLAG_KERNEL;
898 if( *ent & PF_COW ) ret |= MM_PFLAG_COW;
904 * \brief Check if the provided buffer is valid
905 * \return Boolean valid
907 int MM_IsValidBuffer(tVAddr Addr, size_t Size)
912 Size += Addr & (PAGE_SIZE-1);
913 Addr &= ~(PAGE_SIZE-1);
918 // Debug("Addr = %p, Size = 0x%x, dir = %i, tab = %i", Addr, Size, dir, tab);
920 if( !(gaPageDir[dir] & 1) ) return 0;
921 if( !(gaPageTable[tab] & 1) ) return 0;
923 bIsUser = !!(gaPageTable[tab] & PF_USER);
925 while( Size >= PAGE_SIZE )
927 if( (tab & 1023) == 0 )
930 if( !(gaPageDir[dir] & 1) ) return 0;
933 if( !(gaPageTable[tab] & 1) ) return 0;
934 if( bIsUser && !(gaPageTable[tab] & PF_USER) ) return 0;
943 * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
944 * \brief Duplicates a virtual page to a physical one
946 tPAddr MM_DuplicatePage(tVAddr VAddr)
952 //ENTER("xVAddr", VAddr);
955 if( !(gaPageDir [VAddr >> 22] & PF_PRESENT) ) return 0;
956 if( !(gaPageTable[VAddr >> 12] & PF_PRESENT) ) return 0;
962 ret = MM_AllocPhys();
967 // Write-lock the page (to keep data constistent), saving its R/W state
968 wasRO = (gaPageTable[VAddr >> 12] & PF_WRITE ? 0 : 1);
969 gaPageTable[VAddr >> 12] &= ~PF_WRITE;
973 temp = MM_MapTemp(ret);
974 memcpy( temp, (void*)VAddr, 0x1000 );
977 // Restore Writeable status
978 if(!wasRO) gaPageTable[VAddr >> 12] |= PF_WRITE;
986 * \fn Uint MM_MapTemp(tPAddr PAddr)
987 * \brief Create a temporary memory mapping
988 * \todo Show Luigi Barone (C Lecturer) and see what he thinks
990 void *MM_MapTemp(tPAddr PAddr)
992 ENTER("PPAddr", PAddr);
996 if( Semaphore_Wait(&gTempMappingsSem, 1) != 1 )
998 LOG("Semaphore good");
999 Mutex_Acquire( &glTempMappings );
1000 for( int i = 0; i < NUM_TEMP_PAGES; i ++ )
1002 Uint32 *pte = &gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ];
1003 LOG("%i: %x", i, *pte);
1004 // Check if page used
1005 if(*pte & 1) continue;
1008 INVLPG( TEMP_MAP_ADDR + (i << 12) );
1009 LEAVE('p', TEMP_MAP_ADDR + (i << 12));
1010 Mutex_Release( &glTempMappings );
1011 return (void*)( TEMP_MAP_ADDR + (i << 12) );
1013 Mutex_Release( &glTempMappings );
1014 Log_KernelPanic("MMVirt", "Semaphore suplied a mapping, but none are avaliable");
1019 * \fn void MM_FreeTemp(tVAddr PAddr)
1020 * \brief Free's a temp mapping
1022 void MM_FreeTemp(void *VAddr)
1024 int i = (tVAddr)VAddr >> 12;
1025 //ENTER("xVAddr", VAddr);
1027 if(i >= (TEMP_MAP_ADDR >> 12)) {
1028 gaPageTable[ i ] = 0;
1029 Semaphore_Signal(&gTempMappingsSem, 1);
1036 * \fn tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
1037 * \brief Allocates a contigous number of pages
1039 void *MM_MapHWPages(tPAddr PAddr, Uint Number)
1045 if( PAddr < 1024*1024 && (1024*1024-PAddr) >= Number * PAGE_SIZE )
1047 return (void*)(KERNEL_BASE + PAddr);
1051 for( int i = 0; i < NUM_HW_PAGES; i ++ )
1053 // Check if addr used
1054 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i ] & 1 )
1057 // Check possible region
1058 for( j = 0; j < Number && i + j < NUM_HW_PAGES; j ++ )
1060 // If there is an allocated page in the region we are testing, break
1061 if( gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] & 1 ) break;
1067 for( j = 0; j < Number; j++ ) {
1068 MM_RefPhys( PAddr + (j<<12) );
1069 gaPageTable[ (HW_MAP_ADDR >> 12) + i + j ] = (PAddr + (j<<12)) | 3;
1071 return (void*)(HW_MAP_ADDR + (i<<12));
1074 // If we don't find any, return NULL
1079 * \fn tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
1080 * \brief Allocates DMA physical memory
1081 * \param Pages Number of pages required
1082 * \param MaxBits Maximum number of bits the physical address can have
1083 * \param PhysAddr Pointer to the location to place the physical address allocated
1084 * \return Virtual address allocate
1086 void *MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
1091 ENTER("iPages iMaxBits pPhysAddr", Pages, MaxBits, PhysAddr);
1094 MaxBits = PHYS_BITS;
1103 if(Pages == 1 && MaxBits >= PHYS_BITS)
1105 phys = MM_AllocPhys();
1111 ret = MM_MapHWPages(phys, 1);
1122 phys = MM_AllocPhysRange(Pages, MaxBits);
1123 // - Was it allocated?
1129 // Allocated successfully, now map
1130 ret = MM_MapHWPages(phys, Pages);
1131 // - MapHWPages references the memory, so release references
1132 for( int i = 0; i < Pages; i ++ )
1133 MM_DerefPhys(phys + i*PAGE_SIZE);
1146 * \fn void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
1147 * \brief Unmap a hardware page
1149 void MM_UnmapHWPages(volatile void *Base, Uint Number)
1151 tVAddr VAddr = (tVAddr)Base;
1152 //Log_Debug("VirtMem", "MM_UnmapHWPages: (VAddr=0x%08x, Number=%i)", VAddr, Number);
1155 if( KERNEL_BASE <= VAddr && VAddr < KERNEL_BASE + 1024*1024 )
1158 Uint pagenum = VAddr >> 12;
1161 if(VAddr < HW_MAP_ADDR || VAddr+Number*0x1000 > HW_MAP_MAX) return;
1164 Mutex_Acquire( &glTempMappings ); // Temp and HW share a directory, so they share a lock
1166 for( Uint i = 0; i < Number; i ++ )
1168 MM_DerefPhys( gaPageTable[ pagenum + i ] & ~0xFFF );
1169 gaPageTable[ pagenum + i ] = 0;
1170 INVLPG( (tVAddr)(pagenum + i) << 12 );
1173 Mutex_Release( &glTempMappings );