I have created a device in kernel space and the access it in user space using CreateFile
I am able to send ioctl to the driver and they are executed properly. The don't know how to trace what happens after WdfRequestComplete
and upon return I end with error 1 (invalid function). Before this is flagged as dup please note there is a difference with this in that I write my driver ioctl and in that I am using synch io not asynch.
In user space:
fd = CreateFile(dev_path,
(FILE_GENERIC_READ | FILE_GENERIC_WRITE),
(FILE_SHARE_READ | FILE_SHARE_WRITE),
NULL, OPEN_EXISTING, 0, NULL);
// ... error checking code here
DeviceIoControl(fd, // device handler
VIRTQC_CMD_MMAP, // command to send
&inputBuffer,
inputBufferLength,
&outputBuffer,
outputBufferLength,
&returnLength,
(LPOVERLAPPED)NULL); // overlapped structure not needed using sync io
and in Kernel space
status = WdfRequestRetrieveInputBuffer(Request, InputBufferLength, &inputBuffer, NULL);
if (!NT_SUCCESS(status))
{
WdfRequestComplete(Request, STATUS_INVALID_PARAMETER);
return;
}
inputVirtArg = (VirtioQCArg*)inputBuffer;
status = WdfRequestRetrieveOutputBuffer(Request, OutputBufferLength, &outputBuffer, NULL);
if (!NT_SUCCESS(status))
{
WdfRequestComplete(Request, STATUS_INVALID_PARAMETER);
return;
}
outputVirtArg = (VirtioQCArg*)outputBuffer;
switch (IoControlCode)
{
case VIRTQC_CMD_MMAP:
if (PsGetCurrentThread() == irp->Tail.Overlay.Thread)
{
status = CreateAndMapMemory(device, &(inputVirtArg), &(outputVirtArg));
outputVirtArg->flag = (!NT_SUCCESS(status)) ? 0 : 1;
}
else
status = STATUS_UNSUCCESSFUL;
break;
default:
status = STATUS_INVALID_DEVICE_REQUEST;
break;
}
WdfRequestComplete(Request, status);
Update 1:
I have tried WdfRequestCompleteWithInformation(Request, status, OutputBufferLength);
but same result.
Also, I notice that the address of inputBuffer and outputBuffer are the same.
Update 2: I tried doing
temp = ExAllocatePoolWithTag(
NonPagedPool,
PAGE_SIZE,
MEMORY_TAG
);
// other code to
RtlCopyMemory((VirtioQCArg*)outputBuffer, temp, OutputBufferLength);
still get error 1
I had defined my ioctl cmds as enums in my linux driver (which works fine) and when implementing the driver in windows I used the same enum definition.
enum
{
// Module & Execution control (driver API)
VIRTIQC_SET = 200,
VIRTIQC_UNSET,
// more cmds.....
}
In windows defining control codes take a bit more. As explained here the CTL_CODE macro should be used to define new IOCTL control codes.
#define IOCTL_Device_Function CTL_CODE(DeviceType, Function, Method, Access)
In my case I ended up with defining this:
#define VIRTQC_MAP CTL_CODE(FILE_DEVICE_NETWORK, 0xC8, METHOD_IN_DIRECT, FILE_READ_DATA | FILE_WRITE_DATA)
#define VIRTQC_UNMAP CTL_CODE(FILE_DEVICE_NETWORK, 0xC9, METHOD_OUT_DIRECT, FILE_READ_DATA)
I know the function code less than 0x800 are reserved for MS but the device on my host requires this codes so I'm just providing what is being asked.