Kernel Mode Driver Framework >> Assembly (PNP) >> File
WdfDeviceIoDirect(PIO)
參考資訊：
1. Source Code
WdfDeviceIoDirect的概念就是直接Mapping User Buffer，然後Driver使用該Mapped的MDL(Memory Description List)操作，相較於WdfDeviceIoBuffered，因為不須I/O Manager更新回User Buffer，因此，效率會比較好，而如果Driver會操作到DMA(Direct Memory Access)記憶體的話，不適用此方式，雖然司徒目前還沒有寫過DMA相關的Windows Driver，不過依據Microsoft的說明文件來看，使用DMA的話，必須使用另一個API(MmGetMdlVirtualAddress)去取得DMA實體記憶體位址，反之，如果不是DMA的操作，就是PIO(Programmed I/O)方式。
記憶體指標：
| Event | Buffer | Length |
|---|---|---|
| EvtIoRead | Step 1. WdfRequestRetrieveOutputWdmMdl() Step 2. MmGetSystemAddressForMdlSafe() |
傳入的第三個參數 |
| EvtIoWrite | Step 1. WdfRequestRetrieveInputWdmMdl() Step 2. MmGetSystemAddressForMdlSafe() |
傳入的第三個參數 |
main.asm
.386p
.model flat, stdcall
option casemap:none
include c:\masm32\Macros\Strings.mac
include c:\masm32\include\w2k\ntdef.inc
include c:\masm32\include\w2k\ntstatus.inc
include c:\masm32\include\w2k\ntddk.inc
include c:\masm32\include\w2k\ntoskrnl.inc
include c:\masm32\include\w2k\ntddkbd.inc
include c:\masm32\include\wxp\wdm.inc
include c:\masm32\include\wdf\umdf\1.9\wudfddi_types.inc
include c:\masm32\include\wdf\kmdf\1.9\wdf.inc
include c:\masm32\include\wdf\kmdf\1.9\wdftypes.inc
include c:\masm32\include\wdf\kmdf\1.9\wdfglobals.inc
include c:\masm32\include\wdf\kmdf\1.9\wdffuncenum.inc
include c:\masm32\include\wdf\kmdf\1.9\wdfobject.inc
include c:\masm32\include\wdf\kmdf\1.9\wdfdevice.inc
include c:\masm32\include\wdf\kmdf\1.9\wdfdriver.inc
include c:\masm32\include\wdf\kmdf\1.9\wdfrequest.inc
include c:\masm32\include\wdf\kmdf\1.9\wdfio.inc
include c:\masm32\include\wdf\kmdf\1.9\wdfmemory.inc
includelib c:\masm32\lib\wxp\i386\BufferOverflowK.lib
includelib c:\masm32\lib\wxp\i386\ntoskrnl.lib
includelib c:\masm32\lib\wxp\i386\hal.lib
includelib c:\masm32\lib\wxp\i386\wmilib.lib
includelib c:\masm32\lib\wxp\i386\sehupd.lib
includelib c:\masm32\lib\wdf\kmdf\i386\1.9\wdfldr.lib
includelib c:\masm32\lib\wdf\kmdf\i386\1.9\wdfdriverentry.lib
public DriverEntry
.const
DEV_NAME word "\","D","e","v","i","c","e","\","M","y","D","r","i","v","e","r",0
SYM_NAME word "\","D","o","s","D","e","v","i","c","e","s","\","M","y","D","r","i","v","e","r",0
.data
szBuffer byte 255 dup(0)
.code
IrpFileCreate proc Device:WDFDEVICE, Request:WDFREQUEST, FileObject:WDFFILEOBJECT
invoke DbgPrint, $CTA0("IrpFieCreate")
invoke WdfRequestComplete, Request, STATUS_SUCCESS
ret
IrpFileCreate endp
IrpFileClose proc FileObject:WDFFILEOBJECT
invoke DbgPrint, $CTA0("IrpFieClose")
ret
IrpFileClose endp
IrpRead proc Queue:WDFQUEUE, Request:WDFREQUEST, _Length:DWORD
local mdl:PMDL
local len:DWORD
invoke DbgPrint, $CTA0("IrpRead")
invoke strlen, offset szBuffer
inc eax
mov len, eax
invoke WdfRequestRetrieveOutputWdmMdl, Request, addr mdl
MmGetSystemAddressForMdlSafe mdl, LowPagePriority
invoke memcpy, eax, offset szBuffer, len
invoke WdfRequestCompleteWithInformation, Request, STATUS_SUCCESS, len
ret
IrpRead endp
IrpWrite proc Queue:WDFQUEUE, Request:WDFREQUEST, _Length:DWORD
local mdl:PMDL
invoke DbgPrint, $CTA0("IrpWrite")
invoke WdfRequestRetrieveInputWdmMdl, Request, addr mdl
MmGetSystemAddressForMdlSafe mdl, LowPagePriority
invoke memcpy, offset szBuffer, eax, _Length
invoke DbgPrint, $CTA0("Buffer: %s, Length:%d"), offset szBuffer, _Length
invoke WdfRequestCompleteWithInformation, Request, STATUS_SUCCESS, _Length
ret
IrpWrite endp
AddDevice proc Driver:WDFDRIVER, pDeviceInit:PWDFDEVICE_INIT
local device:WDFDEVICE
local suDevName:UNICODE_STRING
local szSymName:UNICODE_STRING
local file_cfg:WDF_FILEOBJECT_CONFIG
local ioqueue_cfg:WDF_IO_QUEUE_CONFIG
invoke RtlInitUnicodeString, addr suDevName, offset DEV_NAME
invoke RtlInitUnicodeString, addr szSymName, offset SYM_NAME
invoke WdfDeviceInitAssignName, pDeviceInit, addr suDevName
invoke WdfDeviceInitSetIoType, pDeviceInit, WdfDeviceIoDirect
invoke WDF_FILEOBJECT_CONFIG_INIT, addr file_cfg, offset IrpFileCreate, offset IrpFileClose, NULL
invoke WdfDeviceInitSetFileObjectConfig, pDeviceInit, addr file_cfg, WDF_NO_OBJECT_ATTRIBUTES
invoke WdfDeviceCreate, addr pDeviceInit, WDF_NO_OBJECT_ATTRIBUTES, addr device
invoke WdfDeviceCreateSymbolicLink, device, addr szSymName
invoke WDF_IO_QUEUE_CONFIG_INIT_DEFAULT_QUEUE, addr ioqueue_cfg, WdfIoQueueDispatchSequential
lea eax, ioqueue_cfg
mov (WDF_IO_QUEUE_CONFIG ptr [eax]).EvtIoRead, offset IrpRead
mov (WDF_IO_QUEUE_CONFIG ptr [eax]).EvtIoWrite, offset IrpWrite
invoke WdfIoQueueCreate, device, addr ioqueue_cfg, WDF_NO_OBJECT_ATTRIBUTES, WDF_NO_HANDLE
ret
AddDevice endp
DriverEntry proc pOurDriver:PDRIVER_OBJECT, pOurRegistry:PUNICODE_STRING
local config:WDF_DRIVER_CONFIG
invoke WDF_DRIVER_CONFIG_INIT, addr config, AddDevice
invoke WdfDriverCreate, pOurDriver, pOurRegistry, WDF_NO_OBJECT_ATTRIBUTES, addr config, WDF_NO_HANDLE
ret
DriverEntry endp
end DriverEntry
.end
IrpWrite()複製User Application的資料到szBuffer
IrpRead()回填資料給User Application
app.asm
.386p
.model flat, stdcall
option casemap:none
include c:\masm32\include\windows.inc
include c:\masm32\include\masm32.inc
include c:\masm32\include\user32.inc
include c:\masm32\include\msvcrt.inc
include c:\masm32\include\kernel32.inc
includelib c:\masm32\lib\user32.lib
includelib c:\masm32\lib\masm32.lib
includelib c:\masm32\lib\msvcrt.lib
includelib c:\masm32\lib\kernel32.lib
.const
DEV_NAME db "\\.\MyDriver",0
MSG_ERR db "failed to open mydriver",10,13,0
MSG_SEND db "I am error",0
MSG_WR db "WR: %s, %d",10,13,0
MSG_RD db "RD: %s, %d",10,13,0
.data?
hFile dd ?
dwRet dd ?
szBuffer db 255 dup(?)
.code
start:
invoke CreateFile, offset DEV_NAME, GENERIC_READ or GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0
.if eax == INVALID_HANDLE_VALUE
invoke crt_printf, offset MSG_ERR
invoke ExitProcess, -1
.endif
mov hFile, eax
invoke StrLen, offset MSG_SEND
inc eax
mov dwRet, eax
invoke crt_printf, offset MSG_WR, offset MSG_SEND, eax
invoke WriteFile, hFile, offset MSG_SEND, dwRet, offset dwRet, 0
invoke crt_memset, offset szBuffer, 0, 255
invoke ReadFile, hFile, offset szBuffer, 255, offset dwRet, 0
invoke crt_printf, offset MSG_RD, offset szBuffer, dwRet
invoke CloseHandle, hFile
invoke ExitProcess, 0
end start
結果
