One question about usb mass-storage lower filter driver
caro...@gmail.com
I got one problem on handling bulk transfer for mass-storage. I really
need a solution for this. Hope someone can answer my question. The
driver is under WDM.
For a certain IRP asking for bulk out transfer data is issued by upper
driver, the lower filter driver will send a return
STATUS_MORE_PROCESSING_REQUIRED to hold the IRP and build another bulk
transfer ,and complete the certain IRP.
So.. in the lower filter driver. It is like the following.
-----------------------------------------------------------------------
DispatchFromUppderDriver ( )
{
if (Irp type != the special irp type)
passIrp(pdx) ; // I only care a certain IRP.
....
Start_Bulk_Tansfer(pdx);
return STATUS_MORE_PROCESSING_REQUIRED;
}
Start_Bulk_Transfer( pdx )
{
....
IoSetCompletionRoutine ( .... , CompleteRoutine,..) ;
IoCallDriver(.., pdx->Hold_Irp) ;
}
CompleteRoutine(..)
{
SetIoCompleteRequest( Hold_Irp);
}
-----------------------------------------------------------------------
But, for some reason, I have to improve the response speed for the
certain Irp.
I just think that I can simply call the same Start_Bulk_Tansfer(pdx)
when the complete routine happen. And, in the meanwhile, lower filter
driver still response the irp with the data updated by previous
Start_Bulk_Tansfer(pdx)
So, in my imagnation, I can do something like the following..
-----------------------------------------------------------------------
AddDevice ()
{
pdx->data_exist = FALSE;
}
DispatchFromUppderDriver ( )
{
if (Irp type != the special irp type)
passIrp(pdx) ;
// I expect the data will be updated by Start_Bulk_Tansfer(pdx);
// The Irp will be complete by the lower filter driver with those
data.
if( pdx->data_exist)
{
//Copy the data to irp parameter and complete the irp.
return;
}
Start_Bulk_Tansfer(pdx); // Start_Bulk_Transfer will set complete
routine and do IoCallDriver( ) ;
return STATUS_MORE_PROCESSING_REQUIRED;
}
Start_Bulk_Transfer( pdx )
{
....
IoSetCompletionRoutine ( .... , CompleteRoutine,..) ;
IoCallDriver(.., pdx->Hold_Irp) ;
}
CompleteRoutine(..)
{
SetIoCompleteRequest( Hold_Irp);
Start_Bulk_Tansfer(pdx); <------ I call it again when the
complete routine happen.
}
-----------------------------------------------------------------------
But the true is that, ony first time Start_Bulk_Tansfer( ) and the
completeRoutine( ) actually happen. And, the 2nd Start_Bulk_Tansfer( )
won't get the complete routine. It looks like the completeRoutine has
been pending. So the certian Irp only can get the 1st time data and
the data won't be updated.
I also do a experimentation. I set a counter to ten, every time the
certain Irp arrived and been finish , the counter will decrease. When
it become zero, the certain Irp will not be complete immediately. The
lower filter driver will return STATUS_MORE_PROCESSING_REQUIRED; Then
the complete routine will happen right away. Just like the following..
if( pdx->data_exist)
{
if (pdx->count == 0)
return STATUS_MORE_PROCESSING_REQUIRED;
else
//Copy the data to irp parameter and complete the irp.
return;
}
I really don't know what mistakes I made. Could someone tell me the
reason of completeRoutine is pending ? or you have other suggestion?
PS : the certain Irp arrived in Dispatche_Level
Thanks,
by
Caro
caro...@gmail.com
> Dear all,
> I got one problem on handling bulk transfer for mass-storage. I really
> need a solution for this. Hope someone can answer my question. The
> driver is under WDM.
>
> For a certain IRP asking for bulk out transfer data is issued by upper
> STATUS_MORE_PROCESSING_REQUIRED to hold the IRP and build another bulk
> transfer ,and complete the certain IRP.
>
> data.
> if( pdx->data_exist)
> {
> //Copy the data to irp parameter and complete the irp.
> return;
> }
>
> Start_Bulk_Tansfer(pdx); // Start_Bulk_Transfer will set complete
> routine and do IoCallDriver( ) ;
> return STATUS_MORE_PROCESSING_REQUIRED;
>
> }
>
> Start_Bulk_Transfer( pdx )
> {
> ....
> IoSetCompletionRoutine ( .... , CompleteRoutine,..) ;
> IoCallDriver(.., pdx->Hold_Irp) ;
>
> }
>
> CompleteRoutine(..)
> {
>
> SetIoCompleteRequest( Hold_Irp);
>
> Start_Bulk_Tansfer(pdx); <------ I call it again when the
> complete routine happen.}
>
> -----------------------------------------------------------------------
> But the true is that, ony first time Start_Bulk_Tansfer( ) and the
> completeRoutine( ) actually happen. And, the 2nd Start_Bulk_Tansfer( )
> won't get the complete routine. It looks like the completeRoutine has
> been pending. So the certian Irp only can get the 1st time data and
> the data won't be updated.
>
> I also do a experimentation. I set a counter to ten, every time the
> certain Irp arrived and been finish , the counter will decrease. When
> the complete routine will happen right away. Just like the following..
> if( pdx->data_exist)
> {
> if (pdx->count == 0)
> return STATUS_MORE_PROCESSING_REQUIRED;
> else
> //Copy the data to irp parameter and complete the irp.
> return;
> }
>
> I really don't know what mistakes I made. Could someone tell me the
> reason of completeRoutine is pending ? or you have other suggestion?
>
> PS : the certain Irp arrived in Dispatche_Level
>
> Thanks,
> by
> Caro
Oh ~ someone suggest me to markpending on Irp from dispach(). But the
situation is the same. I check the book " Programming the Microsoft
Windoes Driver Model". It looks like only issulate how to split one
Irp to severals Irp. So I just wonder if this issue is related multi-
thread. Could someone know how to handle Irp from uppder driver and
send self Irp to lower driver at the same times ? I hope the Irp from
upper driver won't be pending.
Regards,
Caro
Alexander Grigoriev
If the device gets unplugged or fails, the request is completed immediately.
That will cause recursion in your CompleteRoutine and stack overflow.
<caro...@gmail.com> wrote in message
news:b2faa154-d135-488e...@i4g2000prm.googlegroups.com...
Doron Holan [MSFT]
STATUS_PENDING and mark the irp as pending first. run your driver under
Driver Verifier, it will catch these types of errors
d
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<caro...@gmail.com> wrote in message
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