IoCallDriver

NTDEV
1

Hi All,

I have a requirement such that my driver needs to calls its own DispatchRead function ( to avoid code duplication ), I have tried using IoCallDriver(…) with my driver allocating IRP and my driver’s device object and it works fine.

I want to know whether this is OK ( is this generally used in pratice)?
Do you see any other problem which might come up later.

Thanks in advance.
Anand

Try Juno Platinum for Free! Then, only $9.95/month!
Unlimited Internet Access with 250MB of Email Storage.
Visit http://www.juno.com/value to sign up today!

2

This is OK to do, but that wastes an irp stack location (and memory) by
doing so. Also, you should document the code well, this is not a really
common practice so the next person who must fix your code will not
really see what is going on. If you want code reuse, you can have
DispatchRead call a worker function which your other function calls as
well.

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of xxxxx@juno.com
Sent: Thursday, July 21, 2005 1:40 AM
To: Windows System Software Devs Interest List
Subject: [ntdev] IoCallDriver

Hi All,

I have a requirement such that my driver needs to calls its own
DispatchRead function ( to avoid code duplication ), I have tried using
IoCallDriver(…) with my driver allocating IRP and my driver’s device
object and it works fine.

I want to know whether this is OK ( is this generally used in pratice)?
Do you see any other problem which might come up later.

Thanks in advance.
Anand

Try Juno Platinum for Free! Then, only $9.95/month!
Unlimited Internet Access with 250MB of Email Storage.
Visit http://www.juno.com/value to sign up today!

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

You are currently subscribed to ntdev as: xxxxx@windows.microsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com

3

Look at FASTFAT IFS kit code. It uses FatFsdXxx dispatch routines,
immediately (after IRP context creation) calling FatCommonXxx ones which do the
real work.

Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com

----- Original Message -----
From:
To: “Windows System Software Devs Interest List”
Sent: Thursday, July 21, 2005 12:40 PM
Subject: [ntdev] IoCallDriver

>
> Hi All,
>
> I have a requirement such that my driver needs to calls its own
DispatchRead function ( to avoid code duplication ), I have tried using
IoCallDriver(…) with my driver allocating IRP and my driver’s device object
and it works fine.
>
> I want to know whether this is OK ( is this generally used in pratice)?
> Do you see any other problem which might come up later.
>
> Thanks in advance.
> Anand
>
> ___________________________________________________________________
> Try Juno Platinum for Free! Then, only $9.95/month!
> Unlimited Internet Access with 250MB of Email Storage.
> Visit http://www.juno.com/value to sign up today!
>
>
> —
> Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256
>
> You are currently subscribed to ntdev as: xxxxx@storagecraft.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com