X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86%2Fmm_virt.c;h=2fec186bc10e0d9e8ecd5c41d06a2c6d32f06525;hb=e349c65dfdc7bb37c83bcf8eb34f26fe7efc7869;hp=6fa491b8c4762ecc33f6fc27dedb7589bd1ead36;hpb=05e8ae6b8fd960b2d9d3dafb34263fe7bd1cb90b;p=tpg%2Facess2.git diff --git a/Kernel/arch/x86/mm_virt.c b/Kernel/arch/x86/mm_virt.c index 6fa491b8..2fec186b 100644 --- a/Kernel/arch/x86/mm_virt.c +++ b/Kernel/arch/x86/mm_virt.c @@ -9,6 +9,7 @@ * 0xFE - Unused * 0xFF - System Calls / Kernel's User Code */ +#define DEBUG 1 #include #include #include @@ -28,8 +29,6 @@ #define TEMP_MAP_ADDR 0xFEFF0000 // Allows 16 "temp" pages #define NUM_TEMP_PAGES 16 -#define USE_COW 1 - #define PF_PRESENT 0x1 #define PF_WRITE 0x2 #define PF_USER 0x4 @@ -99,7 +98,7 @@ void MM_InstallVirtual() */ void MM_PageFault(Uint Addr, Uint ErrorCode, tRegs *Regs) { - ENTER("xAddr bErrorCode", Addr, ErrorCode); + //ENTER("xAddr bErrorCode", Addr, ErrorCode); // -- Check for COW -- if( gaPageDir [Addr>>22] & PF_PRESENT @@ -107,12 +106,21 @@ void MM_PageFault(Uint Addr, Uint ErrorCode, tRegs *Regs) && gaPageTable[Addr>>12] & PF_COW ) { tPAddr paddr; - paddr = MM_DuplicatePage( Addr ); - MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF ); - gaPageTable[Addr>>12] &= PF_USER; - gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE; + if(MM_GetRefCount( gaPageTable[Addr>>12] & ~0xFFF ) == 1) + { + gaPageTable[Addr>>12] &= ~PF_COW; + gaPageTable[Addr>>12] |= PF_PRESENT|PF_WRITE; + } + else + { + paddr = MM_DuplicatePage( Addr ); + MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF ); + gaPageTable[Addr>>12] &= PF_USER; + gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE; + } + //LOG("Duplicated page at %p to 0x%x", Addr&~0xFFF, gaPageTable[Addr>>12]); INVLPG( Addr & ~0xFFF ); - LEAVE('-'); + //LEAVE('-') return; } @@ -136,7 +144,6 @@ void MM_PageFault(Uint Addr, Uint ErrorCode, tRegs *Regs) MM_DumpTables(0, -1); Panic("Page Fault at 0x%x\n", Regs->eip); - LEAVE('-'); } /** @@ -152,6 +159,22 @@ void MM_DumpTables(tVAddr Start, tVAddr End) const tPAddr MASK = ~0xF98; Start >>= 12; End >>= 12; + + Log("Directory Entries:"); + for(page = Start >> 10; + page < (End >> 10)+1; + page ++) + { + if(gaPageDir[page]) + { + Log(" 0x%08x-0x%08x :: 0x%08x", + page<<22, ((page+1)<<22)-1, + gaPageDir[page]&~0xFFF + ); + } + } + + Log("Table Entries:"); for(page = Start, curPos = Start<<12; page < End; curPos += 0x1000, page++) @@ -161,7 +184,7 @@ void MM_DumpTables(tVAddr Start, tVAddr End) || (gaPageTable[page] & MASK) != expected) { if(expected) { - Log("0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)", + Log(" 0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)", rangeStart, curPos - 1, gaPageTable[rangeStart>>12] & ~0xFFF, (expected & ~0xFFF) - 1, @@ -200,11 +223,18 @@ void MM_DumpTables(tVAddr Start, tVAddr End) */ tPAddr MM_Allocate(Uint VAddr) { + tPAddr paddr; // Check if the directory is mapped if( gaPageDir[ VAddr >> 22 ] == 0 ) { // Allocate directory - gaPageDir[ VAddr >> 22 ] = MM_AllocPhys() | 3; + paddr = MM_AllocPhys(); + if( paddr == 0 ) { + Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0)); + return 0; + } + // Map + gaPageDir[ VAddr >> 22 ] = paddr | 3; // Mark as user if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER; @@ -213,18 +243,25 @@ tPAddr MM_Allocate(Uint VAddr) } // Check if the page is already allocated else if( gaPageTable[ VAddr >> 12 ] != 0 ) { - Warning("MM_Allocate - Allocating to used address"); + Warning("MM_Allocate - Allocating to used address (%p)", VAddr); return gaPageTable[ VAddr >> 12 ] & ~0xFFF; } // Allocate - gaPageTable[ VAddr >> 12 ] = MM_AllocPhys() | 3; + paddr = MM_AllocPhys(); + if( paddr == 0 ) { + Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)", + VAddr, __builtin_return_address(0)); + return 0; + } + // Map + gaPageTable[ VAddr >> 12 ] = paddr | 3; // Mark as user if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER; // Invalidate Cache for address INVLPG( VAddr & ~0xFFF ); - return gaPageTable[ VAddr >> 12 ] & ~0xFFF; + return paddr; } /** @@ -362,7 +399,8 @@ Uint MM_ClearUser() Uint MM_Clone() { Uint i, j; - Uint kStackBase = gCurrentThread->KernelStack - KERNEL_STACK_SIZE; + Uint page = 0; + Uint kStackBase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE; void *tmp; //ENTER(""); @@ -379,34 +417,31 @@ Uint MM_Clone() // Check if table is allocated if( !(gaPageDir[i] & PF_PRESENT) ) { gaTmpDir[i] = 0; + page += 1024; continue; } // Allocate new table gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7); - INVLPG( &gaTmpTable[i*1024] ); + INVLPG( &gaTmpTable[page] ); // Fill - for( j = 0; j < 1024; j ++ ) + for( j = 0; j < 1024; j ++, page++ ) { - if( !(gaPageTable[i*1024+j] & PF_PRESENT) ) { - gaTmpTable[i*1024+j] = 0; + if( !(gaPageTable[page] & PF_PRESENT) ) { + gaTmpTable[page] = 0; continue; } - #if USE_COW // Refrence old page - MM_RefPhys( gaPageTable[i*1024+j] & ~0xFFF ); + MM_RefPhys( gaPageTable[page] & ~0xFFF ); // Add to new table - if(gaPageTable[i*1024+j] & PF_WRITE) { - gaTmpTable[i*1024+j] = (gaPageTable[i*1024+j] & ~PF_WRITE) | PF_COW; - gaPageTable[i*1024+j] = (gaPageTable[i*1024+j] & ~PF_WRITE) | PF_COW; + if(gaPageTable[page] & PF_WRITE) { + gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW; + gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW; + INVLPG( page << 12 ); } else - gaTmpTable[i*1024+j] = gaPageTable[i*1024+j]; - LOG("gaTmpTable[0x%x] = 0x%x", i*1024+j, gaTmpTable[i*1024+j]); - #else - gaTmpTable[i*1024+j] = MM_DuplicatePage( (i*1024+j)<<12 ) | (gaPageTable[i*1024+j]&7); - #endif + gaTmpTable[page] = gaPageTable[page]; } } @@ -607,7 +642,7 @@ Uint MM_MapTemp(tPAddr PAddr) return TEMP_MAP_ADDR + (i << 12); } RELEASE( &gilTempMappings ); - Proc_Yield(); + Threads_Yield(); } }