/* * DOS memory emulation * * Copyright 1995 Alexandre Julliard * Copyright 1996 Marcus Meissner * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA */ #include <signal.h> #include <stdarg.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include "windef.h" #include "winbase.h" #include "excpt.h" #include "winternl.h" #include "wine/winbase16.h" #include "kernel16_private.h" #include "dosexe.h" #include "wine/debug.h" WINE_DEFAULT_DEBUG_CHANNEL(dosmem); WINE_DECLARE_DEBUG_CHANNEL(selector); WORD DOSMEM_0000H; /* segment at 0:0 */ WORD DOSMEM_BiosDataSeg; /* BIOS data segment at 0x40:0 */ WORD DOSMEM_BiosSysSeg; /* BIOS ROM segment at 0xf000:0 */ WORD DOSVM_psp = 0; WORD int16_sel = 0; WORD relay_code_sel = 0; WORD relay_data_sel = 0; /* DOS memory highest address (including HMA) */ #define DOSMEM_SIZE 0x110000 #define DOSMEM_64KB 0x10000 /* * Memory Control Block (MCB) definition * FIXME: implement Allocation Strategy */ #define MCB_DUMP(mc) \ TRACE ("MCB_DUMP base=%p type=%02xh psp=%04xh size=%04xh\n", mc, mc->type, mc->psp , mc->size ) #define MCB_NEXT(mc) \ (MCB*) ((mc->type==MCB_TYPE_LAST) ? NULL : (char*)(mc) + ((mc->size + 1) << 4) ) /* FIXME: should we check more? */ #define MCB_VALID(mc) \ ((mc->type==MCB_TYPE_NORMAL) || (mc->type==MCB_TYPE_LAST)) #define MCB_TYPE_NORMAL 0x4d #define MCB_TYPE_LAST 0x5a #define MCB_PSP_DOS 0x0060 #define MCB_PSP_FREE 0 #include "pshpack1.h" typedef struct { BYTE type; WORD psp; /* segment of owner psp */ WORD size; /* in paragraphs */ BYTE pad[3]; BYTE name[8]; } MCB; #include "poppack.h" /* #define __DOSMEM_DEBUG__ */ #define VM_STUB(x) (0x90CF00CD|(x<<8)) /* INT x; IRET; NOP */ #define VM_STUB_SEGMENT 0xf000 /* BIOS segment */ /* FIXME: this should be moved to the LOL */ static MCB* DOSMEM_root_block; /* when looking at DOS and real mode memory, we activate in three different * modes, depending the situation. * 1/ By default (protected mode), the first MB of memory (actually 0x110000, * when you also look at the HMA part) is always reserved, whatever you do. * We allocated some PM selectors to this memory, even if this area is not * committed at startup * 2/ if a program tries to use the memory through the selectors, we actually * commit this memory, made of: BIOS segment, but also some system * information, usually low in memory that we map for the circumstance also * in the BIOS segment, so that we keep the low memory protected (for NULL * pointer deref catching for example). In this case, we're still in PM * mode, accessing part of the "physical" real mode memory. In fact, we don't * map all the first meg, we keep 64k uncommitted to still catch NULL * pointers dereference * 3/ if the process enters the real mode, then we (also) commit the full first * MB of memory (and also initialize the DOS structures in it). */ /* DOS memory base (linear in process address space) */ static char *DOSMEM_dosmem; static char *DOSMEM_sysmem; /* number of bytes protected from _dosmem. 0 when DOS memory is initialized, * 64k otherwise to trap NULL pointers deref */ static DWORD DOSMEM_protect; static LONG WINAPI dosmem_handler(EXCEPTION_POINTERS* except); static void *vectored_handler; /*********************************************************************** * DOSMEM_FillIsrTable * * Fill the interrupt table with fake BIOS calls to BIOSSEG (0xf000). * * NOTES: * Linux normally only traps INTs performed from or destined to BIOSSEG * for us to handle, if the int_revectored table is empty. Filling the * interrupt table with calls to INT stubs in BIOSSEG allows DOS programs * to hook interrupts, as well as use their familiar retf tricks to call * them, AND let Wine handle any unhooked interrupts transparently. */ static void DOSMEM_FillIsrTable(void) { SEGPTR *isr = (SEGPTR*)DOSMEM_sysmem; int x; for (x=0; x<256; x++) isr[x]=MAKESEGPTR(VM_STUB_SEGMENT,x*4); } static void DOSMEM_MakeIsrStubs(void) { DWORD *stub = (DWORD*)(DOSMEM_dosmem + (VM_STUB_SEGMENT << 4)); int x; for (x=0; x<256; x++) stub[x]=VM_STUB(x); } BIOSDATA* DOSVM_BiosData(void) { return (BIOSDATA *)(DOSMEM_sysmem + 0x400); } /********************************************************************** * DOSMEM_GetTicksSinceMidnight * * Return number of clock ticks since midnight. */ static DWORD DOSMEM_GetTicksSinceMidnight(void) { SYSTEMTIME time; /* This should give us the (approximately) correct * 18.206 clock ticks per second since midnight. */ GetLocalTime( &time ); return (((time.wHour * 3600 + time.wMinute * 60 + time.wSecond) * 18206) / 1000) + (time.wMilliseconds * 1000 / 54927); } /*********************************************************************** * DOSMEM_FillBiosSegments * * Fill the BIOS data segment with dummy values. */ static void DOSMEM_FillBiosSegments(void) { BYTE *pBiosSys = (BYTE*)DOSMEM_dosmem + 0xf0000; BYTE *pBiosROMTable = pBiosSys+0xe6f5; BIOSDATA *pBiosData = DOSVM_BiosData(); static const char bios_date[] = "13/01/99"; /* Clear all unused values */ memset( pBiosData, 0, sizeof(*pBiosData) ); /* FIXME: should check the number of configured drives and ports */ pBiosData->Com1Addr = 0x3f8; pBiosData->Com2Addr = 0x2f8; pBiosData->Lpt1Addr = 0x378; pBiosData->Lpt2Addr = 0x278; pBiosData->InstalledHardware = 0x5463; pBiosData->MemSize = 640; pBiosData->NextKbdCharPtr = 0x1e; pBiosData->FirstKbdCharPtr = 0x1e; pBiosData->VideoMode = 3; pBiosData->VideoColumns = 80; pBiosData->VideoPageSize = 80 * 25 * 2; pBiosData->VideoPageStartAddr = 0xb800; pBiosData->VideoCtrlAddr = 0x3d4; pBiosData->Ticks = DOSMEM_GetTicksSinceMidnight(); pBiosData->NbHardDisks = 2; pBiosData->KbdBufferStart = 0x1e; pBiosData->KbdBufferEnd = 0x3e; pBiosData->RowsOnScreenMinus1 = 24; pBiosData->BytesPerChar = 0x10; pBiosData->ModeOptions = 0x64; pBiosData->FeatureBitsSwitches = 0xf9; pBiosData->VGASettings = 0x51; pBiosData->DisplayCombination = 0x08; pBiosData->DiskDataRate = 0; /* fill ROM configuration table (values from Award) */ *(pBiosROMTable+0x0) = 0x08; /* number of bytes following LO */ *(pBiosROMTable+0x1) = 0x00; /* number of bytes following HI */ *(pBiosROMTable+0x2) = 0xfc; /* model */ *(pBiosROMTable+0x3) = 0x01; /* submodel */ *(pBiosROMTable+0x4) = 0x00; /* BIOS revision */ *(pBiosROMTable+0x5) = 0x74; /* feature byte 1 */ *(pBiosROMTable+0x6) = 0x00; /* feature byte 2 */ *(pBiosROMTable+0x7) = 0x00; /* feature byte 3 */ *(pBiosROMTable+0x8) = 0x00; /* feature byte 4 */ *(pBiosROMTable+0x9) = 0x00; /* feature byte 5 */ /* BIOS date string */ memcpy(pBiosSys+0xfff5, bios_date, sizeof bios_date); /* BIOS ID */ *(pBiosSys+0xfffe) = 0xfc; /* Reboot vector (f000:fff0 or ffff:0000) */ *(DWORD*)(pBiosSys + 0xfff0) = VM_STUB(0x19); } /*********************************************************************** * BiosTick * * Increment the BIOS tick counter. Called by timer signal handler. */ static void CALLBACK BiosTick( LPVOID arg, DWORD low, DWORD high ) { BIOSDATA *pBiosData = arg; pBiosData->Ticks++; } /*********************************************************************** * timer_thread */ static DWORD CALLBACK timer_thread( void *arg ) { LARGE_INTEGER when; HANDLE timer; if (!(timer = CreateWaitableTimerA( NULL, FALSE, NULL ))) return 0; when.u.LowPart = when.u.HighPart = 0; SetWaitableTimer( timer, &when, 55 /* actually 54.925 */, BiosTick, arg, FALSE ); for (;;) SleepEx( INFINITE, TRUE ); } /*********************************************************************** * DOSVM_start_bios_timer * * Start the BIOS ticks timer when the app accesses selector 0x40. */ void DOSVM_start_bios_timer(void) { static LONG running; if (!InterlockedExchange( &running, 1 )) CloseHandle( CreateThread( NULL, 0, timer_thread, DOSVM_BiosData(), 0, NULL )); } /*********************************************************************** * DOSMEM_Collapse * * Helper function for internal use only. * Attach all following free blocks to this one, even if this one is not free. */ static void DOSMEM_Collapse( MCB* mcb ) { MCB* next = MCB_NEXT( mcb ); while (next && next->psp == MCB_PSP_FREE) { mcb->size = mcb->size + next->size + 1; mcb->type = next->type; /* make sure keeping MCB_TYPE_LAST */ next = MCB_NEXT( next ); } } /*********************************************************************** * DOSMEM_InitSegments */ static void DOSMEM_InitSegments(void) { LPSTR ptr; int i; static const char relay[]= { 0xca, 0x04, 0x00, /* 16-bit far return and pop 4 bytes (relay void* arg) */ 0xcd, 0x31, /* int 31 */ }; /* * PM / offset N*5: Interrupt N in 16-bit protected mode. */ int16_sel = GLOBAL_Alloc( GMEM_FIXED, 5 * 256, 0, LDT_FLAGS_CODE ); ptr = GlobalLock16( int16_sel ); for(i=0; i<256; i++) { /* * Each 16-bit interrupt handler is 5 bytes: * 0xCD,<i> = int <i> (interrupt) * 0xCA,0x02,0x00 = ret 2 (16-bit far return and pop 2 bytes / eflags) */ ptr[i * 5 + 0] = 0xCD; ptr[i * 5 + 1] = i; ptr[i * 5 + 2] = 0xCA; ptr[i * 5 + 3] = 0x02; ptr[i * 5 + 4] = 0x00; } GlobalUnlock16( int16_sel ); /* * PM / offset 0: Stub where __wine_call_from_16_regs returns. * PM / offset 3: Stub which swaps back to 32-bit application code/stack. */ relay_code_sel = GLOBAL_Alloc( GMEM_FIXED, sizeof(relay), 0, LDT_FLAGS_CODE ); ptr = GlobalLock16( relay_code_sel ); memcpy( ptr, relay, sizeof(relay) ); GlobalUnlock16( relay_code_sel ); /* * Space for 16-bit stack used by relay code. */ relay_data_sel = GlobalAlloc16( GMEM_FIXED | GMEM_ZEROINIT, DOSVM_RELAY_DATA_SIZE ); } /****************************************************************** * DOSMEM_InitDosMemory */ BOOL DOSMEM_InitDosMemory(void) { static BOOL done; static HANDLE hRunOnce; DWORD old_prot; if (done) return TRUE; /* FIXME: this isn't 100% thread safe, as we won't catch accesses while initializing */ if (hRunOnce == 0) { HANDLE hEvent = CreateEventW( NULL, TRUE, FALSE, NULL ); if (InterlockedCompareExchangePointer( &hRunOnce, hEvent, 0 ) == 0) { BOOL ret; DWORD reserve; /* ok, we're the winning thread */ if (!(ret = VirtualProtect( DOSMEM_dosmem + DOSMEM_protect, DOSMEM_SIZE - DOSMEM_protect, PAGE_READWRITE, &old_prot ))) ERR("Cannot load access low 1Mb, DOS subsystem unavailable\n"); RemoveVectoredExceptionHandler( vectored_handler ); /* * Reserve either: * - lowest 64k for NULL pointer catching (Win16) * - lowest 1k for interrupt handlers and * another 0.5k for BIOS, DOS and intra-application * areas (DOS) */ if (DOSMEM_dosmem != DOSMEM_sysmem) reserve = 0x10000; /* 64k */ else reserve = 0x600; /* 1.5k */ /* * Set DOS memory base and initialize conventional memory. */ DOSMEM_FillBiosSegments(); DOSMEM_FillIsrTable(); /* align root block to paragraph */ DOSMEM_root_block = (MCB*)(DOSMEM_dosmem + reserve); DOSMEM_root_block->type = MCB_TYPE_LAST; DOSMEM_root_block->psp = MCB_PSP_FREE; DOSMEM_root_block->size = (DOSMEM_dosmem + 0x9fffc - ((char*)DOSMEM_root_block)) >> 4; TRACE("DOS conventional memory initialized, %d bytes free.\n", DOSMEM_Available()); DOSMEM_InitSegments(); SetEvent( hRunOnce ); done = TRUE; return ret; } /* someone beat us here... */ CloseHandle( hEvent ); } /* and wait for the winner to have finished */ WaitForSingleObject( hRunOnce, INFINITE ); return TRUE; } /****************************************************************** * dosmem_handler * * Handler to catch access to our 1MB address space reserved for real memory */ static LONG WINAPI dosmem_handler(EXCEPTION_POINTERS* except) { if (except->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION) { char *addr = (char *)except->ExceptionRecord->ExceptionInformation[1]; if (addr >= DOSMEM_dosmem + DOSMEM_protect && addr < DOSMEM_dosmem + DOSMEM_SIZE) { if (DOSMEM_InitDosMemory()) return EXCEPTION_CONTINUE_EXECUTION; } } return EXCEPTION_CONTINUE_SEARCH; } /*********************************************************************** * DOSMEM_Init * * Create the dos memory segments, and store them into the KERNEL * exported values. */ BOOL DOSMEM_Init(void) { void *addr = (void *)1; SIZE_T size = DOSMEM_SIZE - 1; if (NtAllocateVirtualMemory( GetCurrentProcess(), &addr, 0, &size, MEM_RESERVE | MEM_COMMIT, PAGE_NOACCESS )) { ERR( "Cannot allocate DOS memory\n" ); ExitProcess(1); } if (addr <= (void *)DOSMEM_64KB) { DOSMEM_dosmem = 0; DOSMEM_protect = DOSMEM_64KB; DOSMEM_sysmem = (char *)0xf0000; /* store sysmem in high addresses for now */ } else { WARN( "First megabyte not available for DOS address space.\n" ); DOSMEM_dosmem = addr; DOSMEM_protect = 0; DOSMEM_sysmem = DOSMEM_dosmem; } vectored_handler = AddVectoredExceptionHandler(FALSE, dosmem_handler); DOSMEM_0000H = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem, DOSMEM_64KB, 0, LDT_FLAGS_DATA ); DOSMEM_BiosDataSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem + 0x400, 0x100, 0, LDT_FLAGS_DATA ); DOSMEM_BiosSysSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_dosmem + 0xf0000, DOSMEM_64KB, 0, LDT_FLAGS_DATA ); return TRUE; } /*********************************************************************** * DOSMEM_MapLinearToDos * * Linear address to the DOS address space. */ UINT DOSMEM_MapLinearToDos(LPVOID ptr) { if (((char*)ptr >= DOSMEM_dosmem) && ((char*)ptr < DOSMEM_dosmem + DOSMEM_SIZE)) return (char *)ptr - DOSMEM_dosmem; return (UINT)ptr; } /*********************************************************************** * DOSMEM_MapDosToLinear * * DOS linear address to the linear address space. */ LPVOID DOSMEM_MapDosToLinear(UINT ptr) { if (ptr < DOSMEM_SIZE) return DOSMEM_dosmem + ptr; return (LPVOID)ptr; } /*********************************************************************** * DOSMEM_MapRealToLinear * * Real mode DOS address into a linear pointer */ LPVOID DOSMEM_MapRealToLinear(DWORD x) { LPVOID lin; lin = DOSMEM_dosmem + HIWORD(x) * 16 + LOWORD(x); TRACE_(selector)("(0x%08x) returns %p.\n", x, lin ); return lin; } /*********************************************************************** * DOSMEM_AllocBlock * * Carve a chunk of the DOS memory block (without selector). */ LPVOID DOSMEM_AllocBlock(UINT size, UINT16* pseg) { MCB *curr; MCB *next = NULL; WORD psp; DOSMEM_InitDosMemory(); curr = DOSMEM_root_block; if (!(psp = DOSVM_psp)) psp = MCB_PSP_DOS; if (pseg) *pseg = 0; TRACE( "(%04xh)\n", size ); /* round up to paragraph */ size = (size + 15) >> 4; #ifdef __DOSMEM_DEBUG__ DOSMEM_Available(); /* checks the whole MCB list */ #endif /* loop over all MCB and search the next large enough MCB */ while (curr) { if (!MCB_VALID (curr)) { ERR( "MCB List Corrupt\n" ); MCB_DUMP( curr ); return NULL; } if (curr->psp == MCB_PSP_FREE) { DOSMEM_Collapse( curr ); /* is it large enough (one paragraph for the MCB)? */ if (curr->size >= size) { if (curr->size > size) { /* split curr */ next = (MCB *) ((char*) curr + ((size+1) << 4)); next->psp = MCB_PSP_FREE; next->size = curr->size - (size+1); next->type = curr->type; curr->type = MCB_TYPE_NORMAL; curr->size = size; } /* curr is the found block */ curr->psp = psp; if( pseg ) *pseg = (((char*)curr) + 16 - DOSMEM_dosmem) >> 4; return (LPVOID) ((char*)curr + 16); } } curr = MCB_NEXT(curr); } return NULL; } /*********************************************************************** * DOSMEM_FreeBlock */ BOOL DOSMEM_FreeBlock(void* ptr) { MCB* mcb = (MCB*) ((char*)ptr - 16); TRACE( "(%p)\n", ptr ); #ifdef __DOSMEM_DEBUG__ DOSMEM_Available(); #endif if (!MCB_VALID (mcb)) { ERR( "MCB invalid\n" ); MCB_DUMP( mcb ); return FALSE; } mcb->psp = MCB_PSP_FREE; DOSMEM_Collapse( mcb ); return TRUE; } /*********************************************************************** * DOSMEM_ResizeBlock * * Resize DOS memory block in place. Returns block size or -1 on error. * * If exact is TRUE, returned value is either old or requested block * size. If exact is FALSE, block is expanded even if there is not * enough space for full requested block size. * * TODO: return also biggest block size */ UINT DOSMEM_ResizeBlock(void *ptr, UINT size, BOOL exact) { MCB* mcb = (MCB*) ((char*)ptr - 16); MCB* next; TRACE( "(%p,%04xh,%s)\n", ptr, size, exact ? "TRUE" : "FALSE" ); /* round up to paragraph */ size = (size + 15) >> 4; #ifdef __DOSMEM_DEBUG__ DOSMEM_Available(); #endif if (!MCB_VALID (mcb)) { ERR( "MCB invalid\n" ); MCB_DUMP( mcb ); return -1; } /* resize needed? */ if (mcb->size == size) return size << 4; /* collapse free blocks */ DOSMEM_Collapse( mcb ); /* shrink mcb ? */ if (mcb->size > size) { next = (MCB *) ((char*)mcb + ((size+1) << 4)); next->type = mcb->type; next->psp = MCB_PSP_FREE; next->size = mcb->size - (size+1); mcb->type = MCB_TYPE_NORMAL; mcb->size = size; return size << 4; } if (!exact) { return mcb->size << 4; } return -1; } /*********************************************************************** * DOSMEM_Available */ UINT DOSMEM_Available(void) { UINT available = 0; UINT total = 0; MCB *curr = DOSMEM_root_block; /* loop over all MCB and search the largest free MCB */ while (curr) { #ifdef __DOSMEM_DEBUG__ MCB_DUMP( curr ); #endif if (!MCB_VALID (curr)) { ERR( "MCB List Corrupt\n" ); MCB_DUMP( curr ); return 0; } if (curr->psp == MCB_PSP_FREE && curr->size > available ) available = curr->size; total += curr->size + 1; curr = MCB_NEXT( curr ); } TRACE( " %04xh of %04xh paragraphs available\n", available, total ); return available << 4; } /****************************************************************** * DOSMEM_MapDosLayout * * Initialize the first MB of memory to look like a real DOS setup */ BOOL DOSMEM_MapDosLayout(void) { static BOOL already_mapped; DWORD old_prot; if (!already_mapped) { if (DOSMEM_dosmem || !VirtualProtect( NULL, DOSMEM_SIZE, PAGE_EXECUTE_READWRITE, &old_prot )) { ERR( "Need full access to the first megabyte for DOS mode\n" ); ExitProcess(1); } /* copy the BIOS and ISR area down */ memcpy( DOSMEM_dosmem, DOSMEM_sysmem, 0x400 + 0x100 ); DOSMEM_sysmem = DOSMEM_dosmem; SetSelectorBase( DOSMEM_0000H, 0 ); SetSelectorBase( DOSMEM_BiosDataSeg, 0x400 ); /* we may now need the actual interrupt stubs, and since we've just moved the * interrupt vector table away, we can fill the area with stubs instead... */ DOSMEM_MakeIsrStubs(); already_mapped = TRUE; } return TRUE; }