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/*
* 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 "config.h"
#include "wine/port.h"
#include <signal.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#ifdef HAVE_SYS_MMAN_H
# include <sys/mman.h>
#endif
#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 */
/* 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_InitDosMemory
*/
BOOL DOSMEM_InitDosMemory(void)
{
static BOOL done;
static HANDLE hRunOnce;
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, NULL )))
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());
DOSVM_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, WINE_LDT_FLAGS_DATA );
DOSMEM_BiosDataSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_sysmem + 0x400,
0x100, 0, WINE_LDT_FLAGS_DATA );
DOSMEM_BiosSysSeg = GLOBAL_CreateBlock( GMEM_FIXED, DOSMEM_dosmem + 0xf0000,
DOSMEM_64KB, 0, WINE_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;
if (!already_mapped)
{
if (DOSMEM_dosmem || !VirtualProtect( NULL, DOSMEM_SIZE, PAGE_EXECUTE_READWRITE, NULL ))
{
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;
}