WDM needs for a filter driver

NTFSD
1

Hello,

I’ve been told to make our NT file system filter driver WDM compliant. Is it
enough that I simply pass down all the WDM irp’s? I sure hope so :slight_smile:

ps. It does *not* need to run on 95 or 98.

tia,
Marc

2

By their very nature, file system filter drivers are not WDM compliant.
There are no WDM compliance tests, WHQL will not certify a file system
filter driver to be WDM compliant, etc. Besides, if you don’t want
portability to Windows 98 or ME what would be the POINT of a WDM filter
driver?

This sounds like a marketing/management level request from someone who knows
the buzzword but doesn’t understand that it is a meaningless request.

Regards,

Tony

Tony Mason
Consulting Partner
OSR Open Systems Resources, Inc.
http://www.osr.com http:

-----Original Message-----
From: Marc Sherman [mailto:xxxxx@bionetrix.com]
Sent: Friday, June 23, 2000 11:12 AM
To: File Systems Developers
Subject: [ntfsd] WDM needs for a filter driver

Hello,

I’ve been told to make our NT file system filter driver WDM compliant. Is it
enough that I simply pass down all the WDM irp’s? I sure hope so :slight_smile:

ps. It does not need to run on 95 or 98.

tia,
Marc</http:>

3

More specifically, do I need to handle the new irp’s for pnp, power, and
wmi? Do fs filter drivers get signed by Microsoft for Win2000? If so, do I
need to handle theses irp’s to get signed? If I don’t handle the power
irp’s, will I prevent the machine form going into hibernate mode?

sorry for the run on questions,
Marc

-----Original Message-----
From: Tony Mason [mailto:xxxxx@osr.com]
Sent: Friday, June 23, 2000 11:15 AM
To: File Systems Developers
Subject: [ntfsd] RE: WDM needs for a filter driver

By their very nature, file system filter drivers are not WDM
compliant.
There are no WDM compliance tests, WHQL will not certify a file system
filter driver to be WDM compliant, etc. Besides, if you don’t want
portability to Windows 98 or ME what would be the POINT of a
WDM filter
driver?

This sounds like a marketing/management level request from
someone who knows
the buzzword but doesn’t understand that it is a meaningless request.

Regards,

Tony

Tony Mason
Consulting Partner
OSR Open Systems Resources, Inc.
http://www.osr.com http:
>
>
> -----Original Message-----
> From: Marc Sherman [mailto:xxxxx@bionetrix.com]
> Sent: Friday, June 23, 2000 11:12 AM
> To: File Systems Developers
> Subject: [ntfsd] WDM needs for a filter driver
>
>
>
> Hello,
>
> I’ve been told to make our NT file system filter driver WDM
> compliant. Is it
> enough that I simply pass down all the WDM irp’s? I sure hope so :slight_smile:
>
> ps. It does not need to run on 95 or 98.
>
> tia,
> Marc
>
>
> —
> You are currently subscribed to ntfsd as: xxxxx@bionetrix.com
> To unsubscribe send a blank email to $subst(‘Email.Unsub’)
></http:>

4

Marc,

If you find a file system that you are filtering that handles power IRPs (or
IRP_MJ_SYSTEM_CONTROL) then yes, you must handle them. IRP_MJ_PNP must be
handled because the file system use them. But “handling” these IRPs is
nothing more than a few dozen lines of code. Right now, though, the file
systems don’t support power management so you don’t need to either.

As for certification, Microsoft is working towards certifying file system
filter drivers but they do not do so at the present time. They have a test
suite that will form the basis of that certification process, though, and
you’d be wise to make sure you run that and the driver verifier as precursor
steps towards certification (and, more importantly, to ensuring there are no
bugs in your filter.)

Regards,

Tony

Tony Mason
Consulting Partner
OSR Open Systems Resources, Inc.
http://www.osr.com http:

-----Original Message-----
From: Marc Sherman [mailto:xxxxx@bionetrix.com]
Sent: Friday, June 23, 2000 11:34 AM
To: File Systems Developers
Subject: [ntfsd] RE: WDM needs for a filter driver

More specifically, do I need to handle the new irp’s for pnp, power, and
wmi? Do fs filter drivers get signed by Microsoft for Win2000? If so, do I
need to handle theses irp’s to get signed? If I don’t handle the power
irp’s, will I prevent the machine form going into hibernate mode?

sorry for the run on questions,
Marc

> -----Original Message-----
> From: Tony Mason [mailto:xxxxx@osr.com mailto:xxxxx]
> Sent: Friday, June 23, 2000 11:15 AM
> To: File Systems Developers
> Subject: [ntfsd] RE: WDM needs for a filter driver
>
>
> By their very nature, file system filter drivers are not WDM
> compliant.
> There are no WDM compliance tests, WHQL will not certify a file system
> filter driver to be WDM compliant, etc. Besides, if you don’t want
> portability to Windows 98 or ME what would be the POINT of a
> WDM filter
> driver?
>
> This sounds like a marketing/management level request from
> someone who knows
> the buzzword but doesn’t understand that it is a meaningless request.
>
> Regards,
>
> Tony
>
> Tony Mason
> Consulting Partner
> OSR Open Systems Resources, Inc.
> http://www.osr.com http: < http://www.osr.com
http: >
>
>
> -----Original Message-----
> From: Marc Sherman [mailto:xxxxx@bionetrix.com
mailto:xxxxx]
> Sent: Friday, June 23, 2000 11:12 AM
> To: File Systems Developers
> Subject: [ntfsd] WDM needs for a filter driver
>
>
>
> Hello,
>
> I’ve been told to make our NT file system filter driver WDM
> compliant. Is it
> enough that I simply pass down all the WDM irp’s? I sure hope so :slight_smile:
>
> ps. It does not need to run on 95 or 98.
>
> tia,
> Marc
>
>
> —
> You are currently subscribed to ntfsd as: xxxxx@bionetrix.com
> To unsubscribe send a blank email to $subst(‘Email.Unsub’)
></mailto:xxxxx></http:></http:></mailto:xxxxx></http:>

5

Tony,

Thanks for your help :slight_smile:

Marc

-----Original Message-----
From: Tony Mason [mailto:xxxxx@osr.com]
Sent: Friday, June 23, 2000 11:38 AM
To: File Systems Developers
Subject: [ntfsd] RE: WDM needs for a filter driver

Marc,

If you find a file system that you are filtering that handles
power IRPs (or
IRP_MJ_SYSTEM_CONTROL) then yes, you must handle them.
IRP_MJ_PNP must be
handled because the file system use them. But “handling”
these IRPs is
nothing more than a few dozen lines of code. Right now,
though, the file
systems don’t support power management so you don’t need to either.

As for certification, Microsoft is working towards certifying
file system
filter drivers but they do not do so at the present time.
They have a test
suite that will form the basis of that certification process,
though, and
you’d be wise to make sure you run that and the driver
verifier as precursor
steps towards certification (and, more importantly, to
ensuring there are no
bugs in your filter.)

Regards,

Tony

Tony Mason
Consulting Partner
OSR Open Systems Resources, Inc.
http://www.osr.com http:
>
>
> -----Original Message-----
> From: Marc Sherman [mailto:xxxxx@bionetrix.com]
> Sent: Friday, June 23, 2000 11:34 AM
> To: File Systems Developers
> Subject: [ntfsd] RE: WDM needs for a filter driver
>
>
>
> More specifically, do I need to handle the new irp’s for pnp,
> power, and
> wmi? Do fs filter drivers get signed by Microsoft for
> Win2000? If so, do I
> need to handle theses irp’s to get signed? If I don’t handle the power
> irp’s, will I prevent the machine form going into hibernate mode?
>
> sorry for the run on questions,
> Marc
>
> > -----Original Message-----
> > From: Tony Mason [mailto:xxxxx@osr.com mailto:xxxxx]
> > Sent: Friday, June 23, 2000 11:15 AM
> > To: File Systems Developers
> > Subject: [ntfsd] RE: WDM needs for a filter driver
> >
> >
> > By their very nature, file system filter drivers are not WDM
> > compliant.
> > There are no WDM compliance tests, WHQL will not certify a
> file system
> > filter driver to be WDM compliant, etc. Besides, if you don’t want
> > portability to Windows 98 or ME what would be the POINT of a
> > WDM filter
> > driver?
> >
> > This sounds like a marketing/management level request from
> > someone who knows
> > the buzzword but doesn’t understand that it is a
> meaningless request.
> >
> > Regards,
> >
> > Tony
> >
> > Tony Mason
> > Consulting Partner
> > OSR Open Systems Resources, Inc.
> > http://www.osr.com http: < http://www.osr.com
> http: >
> >
> >
> > -----Original Message-----
> > From: Marc Sherman [mailto:xxxxx@bionetrix.com
> mailto:xxxxx]
> > Sent: Friday, June 23, 2000 11:12 AM
> > To: File Systems Developers
> > Subject: [ntfsd] WDM needs for a filter driver
> >
> >
> >
> > Hello,
> >
> > I’ve been told to make our NT file system filter driver WDM
> > compliant. Is it
> > enough that I simply pass down all the WDM irp’s? I sure
> hope so :slight_smile:
> >
> > ps. It does not need to run on 95 or 98.
> >
> > tia,
> > Marc
> >
> >
> > —
> > You are currently subscribed to ntfsd as: xxxxx@bionetrix.com
> > To unsubscribe send a blank email to
> $subst(‘Email.Unsub’)
> >
>
>
> —
> You are currently subscribed to ntfsd as: xxxxx@bionetrix.com
> To unsubscribe send a blank email to $subst(‘Email.Unsub’)
></mailto:xxxxx></http:></http:></mailto:xxxxx></http:>