Re: FW: Does windows detects UDF formatted hard disk?

NTFSD
1

Hi Tony,

Thanks for the information.

I checked in our Windows 2000 machine also. As you said, the UDFS file
system has two device objects for FILE_DEVICE_DISK_FILE_SYSTEM and
FILE_DEVICE_CD_ROM_FILE_SYSTEM. Hence it would mean that it should be given
the opportunity to mount on disk as well as CD/DVD devices, right?
As you said, the last registered file system will be called first. So how
can we change the order in which the registration happens?

As far as changing the load order is concerned, what I observed is that, a
file system recognizer is registered with a start type 1(system start) and
group “boot file system”. The fs_rec has device objects
like"UdfsDiskRecognizer" and “UdfsCdromRecognizer”. The actual UDFS file
system driver has a start type of 4(disabled), which will be called by the
recognizer. So in this case how can we make the “UdfsDiskRecognizer” to be
called first to recognize the volume?

Also NTFS does not have a recognizer. Hence does it mean that NTFS is always
being called first to mount on a device?

Thanks,
Saritha.

-----Original Message-----
*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com]*On Behalf Of *Tony Mason
*Sent:* Tuesday, March 07, 2006 1:14 AM
*To:* Windows File Systems Devs Interest List
*Subject:* RE: [ntfsd] Does windows detects UDF formatted hard disk?

Each file system implementation is free to decide how it recognizes its
own file system type. The UDFS file system (at least on my XP box) has
registered for both CD and DISK mount events, so I would assume it can
recognize a UDFS formatted disk drive type. With a tool like objdir or
winobj or the debugger, you should be able to determine what the UDFS driver
has registered as well (the device objects with names have normally been
registered for mount events.)

The media type does matter ? Windows only supports mount on four media
types: FILE_DEVICE_DISK, FILE_DEVICE_TAPE, FILE_DEVICE_CD_ROM,
FILE_DEVICE_VIRTUAL_DISK ? with the latter being “lumped into” the same file
system type as the first one. File systems of type
FILE_DEVICE_DISK_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_DISK or FILE_DEVICE_VIRTUAL_DISK media. File systems of type
FILE_DEVICE_CD_ROM_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_CD_ROM, etc.

To achieve this, the file system must create a unique device object and
register that device object with the I/O Manager (IoRegisterFileSystem).
The I/O Manager then maintains a LIFO call table of file systems (last
registered, first called) that are invoked to check a media device and
determine if the volume in question has the right format.

One issue I’ve seen interfere with mounting in the past is that the I/O
Manager is very sensitive to errors returned by the mounting file system.
It expects STATUS_UNRECOGNIZED_VOLUME (see FatMountVolume in fsctrl.c for
FAT). Other errors can (and do) cause mounting problems. For example, we
had an FSD that was written to work with WORM media. If NTFS were asked to
mount the volume first and it attempted to read an unrecorded area on the
media it would get an I/O error (indicating that the sector had not yet been
recorded). NTFS would report this error to the I/O Manager and the I/O
Manager would abort the mount processing ? so our file system never was
given an opportunity to mount. Different media, or different load ordering
and the mount proceeded correctly. This was many years ago and at the time
I lobbied for changes to the I/O Manager to be a bit more liberal in its
decision to continue mount processing but was told that this wouldn’t happen
because it only affected a non-MS file system.

Bottom line: mount processing is an elaborate dance with multiple players,
each of whom must behave in a proscribed manner. A failure to do so may
lead to cases where a volume may not behave the way that you expect.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in Boston,
MA April 18-21, 2006 (note new date - MS scheduled plugfest the same week
again.)

*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com] *On Behalf Of *Saritha Vinod
*Sent:* Monday, March 06, 2006 7:16 AM
*To:* ntfsd redirect
*Subject:* [ntfsd] Does windows detects UDF formatted hard disk?

Hi all,

I am trying to format a hard disk partition using UDF file system. Since
windows 2000 does not have write support for UDF, I formatted using Linux
and was able to read and write to it. The UDF version used was 1.50. I
tried accessing that partition again in Windows. But windows failed to
recognize it and showed that it is not formatted. Can anybody please tell me
the reason for this? Is it that windows will not recognize UDF on hard disk,
since it tries to mount UDF only for CD/DVD devices?

Is the media type in anyway related to this behaviour?

Thanks in advance.

Saritha.

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a blank
email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag argument: ‘’

To unsubscribe send a blank email to xxxxx@lists.osr.com

The information contained in this electronic message and any attachments
to this message are intended for the exclusive use of the addressee(s)and
may contain confidential or privileged information. If you are not the
intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

2

If the FS Recognizer’s UDFS objects are in use, the UDFS file system has
not been loaded - FS Recognizer is a “stand in” driver that is used to
defer loading of the regular file system until it is needed. To
determine more would require a bit of work with the debugger (e.g.,
check and see if the recognizer is being called to mount the volume.)
If its not being called, then the next “trick” would be to force the
loading of UDFS (which would then cause registration, which would then
mean it gets called prior to NTFS.) Seriously, this is something that
you should be able to figure out in about 10-15 minutes with a kernel
debugger attached (I’ve had to do this before.) Look at the fs
recognizer’s device object, set a break point in its fs control function
and watch to see if it gets called with the UDFS recognizer object. If
it doesn’t then do the same thing to NTFS and watch its return code -
that’s going to be the key to the whole thing.

I’m not sure how the service control manager handles disabled drivers
anymore. If you can’t start it through the SCM, you’ll need to call
ZwLoadDriver directly to accomplish this.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in
Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest the
same week again.)

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com http:

Looking forward to seeing you at the next OSR File Systems class in
Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest the
same week again.)



From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Saritha Vinod
Sent: Tuesday, March 07, 2006 1:23 AM
To: ntfsd redirect
Subject: Re: FW: [ntfsd] Does windows detects UDF formatted hard disk?

Hi Tony,

Thanks for the information.

I checked in our Windows 2000 machine also. As you said, the UDFS file
system has two device objects for FILE_DEVICE_DISK_FILE_SYSTEM and
FILE_DEVICE_CD_ROM_FILE_SYSTEM. Hence it would mean that it should be
given the opportunity to mount on disk as well as CD/DVD devices, right?

As you said, the last registered file system will be called first. So
how can we change the order in which the registration happens?

As far as changing the load order is concerned, what I observed is that,
a file system recognizer is registered with a start type 1(system start)
and group “boot file system”. The fs_rec has device objects
like"UdfsDiskRecognizer" and “UdfsCdromRecognizer”. The actual UDFS file
system driver has a start type of 4(disabled), which will be called by
the recognizer. So in this case how can we make the “UdfsDiskRecognizer”
to be called first to recognize the volume?

Also NTFS does not have a recognizer. Hence does it mean that NTFS is
always being called first to mount on a device?

Thanks,

Saritha.

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com]On Behalf Of Tony Mason
Sent: Tuesday, March 07, 2006 1:14 AM
To: Windows File Systems Devs Interest List
Subject: RE: [ntfsd] Does windows detects UDF formatted hard
disk?

Each file system implementation is free to decide how it
recognizes its own file system type. The UDFS file system (at least on
my XP box) has registered for both CD and DISK mount events, so I would
assume it can recognize a UDFS formatted disk drive type. With a tool
like objdir or winobj or the debugger, you should be able to determine
what the UDFS driver has registered as well (the device objects with
names have normally been registered for mount events.)

The media type does matter - Windows only supports mount on four
media types: FILE_DEVICE_DISK, FILE_DEVICE_TAPE, FILE_DEVICE_CD_ROM,
FILE_DEVICE_VIRTUAL_DISK - with the latter being “lumped into” the same
file system type as the first one. File systems of type
FILE_DEVICE_DISK_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_DISK or FILE_DEVICE_VIRTUAL_DISK media. File systems of
type FILE_DEVICE_CD_ROM_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_CD_ROM, etc.

To achieve this, the file system must create a unique device
object and register that device object with the I/O Manager
(IoRegisterFileSystem). The I/O Manager then maintains a LIFO call
table of file systems (last registered, first called) that are invoked
to check a media device and determine if the volume in question has the
right format.

One issue I’ve seen interfere with mounting in the past is that
the I/O Manager is very sensitive to errors returned by the mounting
file system. It expects STATUS_UNRECOGNIZED_VOLUME (see FatMountVolume
in fsctrl.c for FAT). Other errors can (and do) cause mounting
problems. For example, we had an FSD that was written to work with WORM
media. If NTFS were asked to mount the volume first and it attempted
to read an unrecorded area on the media it would get an I/O error
(indicating that the sector had not yet been recorded). NTFS would
report this error to the I/O Manager and the I/O Manager would abort the
mount processing - so our file system never was given an opportunity to
mount. Different media, or different load ordering and the mount
proceeded correctly. This was many years ago and at the time I lobbied
for changes to the I/O Manager to be a bit more liberal in its decision
to continue mount processing but was told that this wouldn’t happen
because it only affected a non-MS file system.

Bottom line: mount processing is an elaborate dance with
multiple players, each of whom must behave in a proscribed manner. A
failure to do so may lead to cases where a volume may not behave the way
that you expect.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com http:</http:>

Looking forward to seeing you at the next OSR File Systems class
in Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest
the same week again.)



From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Saritha Vinod
Sent: Monday, March 06, 2006 7:16 AM
To: ntfsd redirect
Subject: [ntfsd] Does windows detects UDF formatted hard disk?

Hi all,

I am trying to format a hard disk partition using UDF file
system. Since windows 2000 does not have write support for UDF, I
formatted using Linux and was able to read and write to it. The UDF
version used was 1.50. I tried accessing that partition again in
Windows. But windows failed to recognize it and showed that it is not
formatted. Can anybody please tell me the reason for this? Is it that
windows will not recognize UDF on hard disk, since it tries to mount UDF
only for CD/DVD devices?

Is the media type in anyway related to this behaviour?

Thanks in advance.

Saritha.

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a
blank email to xxxxx@lists.osr.com

—
Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag
argument: ‘’
To unsubscribe send a blank email to
xxxxx@lists.osr.com

The information contained in this electronic message and any
attachments to this message are intended for the exclusive use of the
addressee(s)and may contain confidential or privileged information. If
you are not the intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a
blank email to xxxxx@lists.osr.com</http:>

3

>I’m not sure how the service control manager handles disabled drivers

anymore. If you can’t start it through the SCM, you’ll need to call
ZwLoadDriver directly to accomplish this.

ZwLoadDriver always ignored the Disabled start type since NT4.

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

4

Hence why I said “if you can’t start it through the SCM, you’ll need to
call ZwLoadDriver to accomplish this.” Since the “sc” utility can be
used to start a driver (trivially) it’s clearly a good choice to try
first.

If you are disagreeing with my statement, it isn’t clear. If you are
merely agreeing, that’s not clear either. Or do you know of a utility
that directly invokes ZwLoadDriver?

Regards,

Tony

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

Looking forward to seeing you at the next OSR File Systems class in
Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest the
same week again.)

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Maxim S. Shatskih
Sent: Tuesday, March 07, 2006 8:11 PM
To: ntfsd redirect
Subject: Re: FW: [ntfsd] Does windows detects UDF formatted hard disk?

I’m not sure how the service control manager handles disabled drivers
anymore. If you can’t start it through the SCM, you’ll need to call
ZwLoadDriver directly to accomplish this.

ZwLoadDriver always ignored the Disabled start type since NT4.

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

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

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

5

>If you are disagreeing with my statement, it isn’t clear.

No, I’m providing the additional info to your statement.

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

6

Hi Tony,

I will check it with a debugger and get back to you.

Also, does NTFS have a recognizer or is it being directly loaded? Does that
mean that NTFS will be the first one to be given the opportunity to mount?

Thanks,
Saritha.

-----Original Message-----
*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com]*On Behalf Of *Tony Mason
*Sent:* Tuesday, March 07, 2006 10:48 PM
*To:* Windows File Systems Devs Interest List
*Subject:* RE: FW: [ntfsd] Does windows detects UDF formatted hard disk?

If the FS Recognizer’s UDFS objects are in use, the UDFS file system has
not been loaded ? FS Recognizer is a “stand in” driver that is used to defer
loading of the regular file system until it is needed. To determine more
would require a bit of work with the debugger (e.g., check and see if the
recognizer is being called to mount the volume.) If its not being called,
then the next “trick” would be to force the loading of UDFS (which would
then cause registration, which would then mean it gets called prior to
NTFS.) Seriously, this is something that you should be able to figure out
in about 10-15 minutes with a kernel debugger attached (I’ve had to do this
before.) Look at the fs recognizer’s device object, set a break point in
its fs control function and watch to see if it gets called with the UDFS
recognizer object. If it doesn’t then do the same thing to NTFS and watch
its return code ? that’s going to be the key to the whole thing.

I’m not sure how the service control manager handles disabled drivers
anymore. If you can’t start it through the SCM, you’ll need to call
ZwLoadDriver directly to accomplish this.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in Boston,
MA April 18-21, 2006 (note new date - MS scheduled plugfest the same week
again.)

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in Boston,
MA April **18-21, 2006 (note new date - MS scheduled plugfest the same
week again.)

*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com] *On Behalf Of *Saritha Vinod
*Sent:* Tuesday, March 07, 2006 1:23 AM
*To:* ntfsd redirect
*Subject:* Re: FW: [ntfsd] Does windows detects UDF formatted hard disk?

Hi Tony,

Thanks for the information.

I checked in our Windows 2000 machine also. As you said, the UDFS file
system has two device objects for FILE_DEVICE_DISK_FILE_SYSTEM and
FILE_DEVICE_CD_ROM_FILE_SYSTEM. Hence it would mean that it should be given
the opportunity to mount on disk as well as CD/DVD devices, right?

As you said, the last registered file system will be called first. So how
can we change the order in which the registration happens?

As far as changing the load order is concerned, what I observed is that, a
file system recognizer is registered with a start type 1(system start) and
group “boot file system”. The fs_rec has device objects
like"UdfsDiskRecognizer" and “UdfsCdromRecognizer”. The actual UDFS file
system driver has a start type of 4(disabled), which will be called by the
recognizer. So in this case how can we make the “UdfsDiskRecognizer” to be
called first to recognize the volume?

Also NTFS does not have a recognizer. Hence does it mean that NTFS is
always being called first to mount on a device?

Thanks,

Saritha.

-----Original Message-----
*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com]*On Behalf Of *Tony Mason
*Sent:* Tuesday, March 07, 2006 1:14 AM
*To:* Windows File Systems Devs Interest List
*Subject:* RE: [ntfsd] Does windows detects UDF formatted hard disk?

Each file system implementation is free to decide how it recognizes its
own file system type. The UDFS file system (at least on my XP box) has
registered for both CD and DISK mount events, so I would assume it can
recognize a UDFS formatted disk drive type. With a tool like objdir or
winobj or the debugger, you should be able to determine what the UDFS driver
has registered as well (the device objects with names have normally been
registered for mount events.)

The media type does matter ? Windows only supports mount on four media
types: FILE_DEVICE_DISK, FILE_DEVICE_TAPE, FILE_DEVICE_CD_ROM,
FILE_DEVICE_VIRTUAL_DISK ? with the latter being “lumped into” the same file
system type as the first one. File systems of type
FILE_DEVICE_DISK_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_DISK or FILE_DEVICE_VIRTUAL_DISK media. File systems of type
FILE_DEVICE_CD_ROM_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_CD_ROM, etc.

To achieve this, the file system must create a unique device object and
register that device object with the I/O Manager (IoRegisterFileSystem).
The I/O Manager then maintains a LIFO call table of file systems (last
registered, first called) that are invoked to check a media device and
determine if the volume in question has the right format.

One issue I’ve seen interfere with mounting in the past is that the I/O
Manager is very sensitive to errors returned by the mounting file system.
It expects STATUS_UNRECOGNIZED_VOLUME (see FatMountVolume in fsctrl.c for
FAT). Other errors can (and do) cause mounting problems. For example, we
had an FSD that was written to work with WORM media. If NTFS were asked to
mount the volume first and it attempted to read an unrecorded area on the
media it would get an I/O error (indicating that the sector had not yet been
recorded). NTFS would report this error to the I/O Manager and the I/O
Manager would abort the mount processing ? so our file system never was
given an opportunity to mount. Different media, or different load ordering
and the mount proceeded correctly. This was many years ago and at the time
I lobbied for changes to the I/O Manager to be a bit more liberal in its
decision to continue mount processing but was told that this wouldn’t happen
because it only affected a non-MS file system.

Bottom line: mount processing is an elaborate dance with multiple players,
each of whom must behave in a proscribed manner. A failure to do so may
lead to cases where a volume may not behave the way that you expect.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in
Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest the
same week again.)

*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com] *On Behalf Of *Saritha Vinod
*Sent:* Monday, March 06, 2006 7:16 AM
*To:* ntfsd redirect
*Subject:* [ntfsd] Does windows detects UDF formatted hard disk?

Hi all,

I am trying to format a hard disk partition using UDF file system. Since
windows 2000 does not have write support for UDF, I formatted using Linux
and was able to read and write to it. The UDF version used was 1.50. I
tried accessing that partition again in Windows. But windows failed to
recognize it and showed that it is not formatted. Can anybody please tell me
the reason for this? Is it that windows will not recognize UDF on hard disk,
since it tries to mount UDF only for CD/DVD devices?

Is the media type in anyway related to this behaviour?

Thanks in advance.

Saritha.

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a blank
email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag argument: ‘’

To unsubscribe send a blank email to xxxxx@lists.osr.com

The information contained in this electronic message and any attachments
to this message are intended for the exclusive use of the addressee(s)and
may contain confidential or privileged information. If you are not the
intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a blank
email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag argument: ‘’

To unsubscribe send a blank email to xxxxx@lists.osr.com

The information contained in this electronic message and any attachments
to this message are intended for the exclusive use of the addressee(s)and
may contain confidential or privileged information. If you are not the
intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

7

What file systems are loaded depends upon what file systems are needed.
The point of using the recognizer is that it means you don’t load file
systems until you really need them. But if NTFS is your boot file
system then it will be loaded. If you booted off FAT then IT would be
loaded. The first time that something accesses a CD-ROM (oh, like
autoplay in Explorer) then CDFS or UDFS will load, etc.

So, there is no definitive answer here - the loading process is dynamic
and based upon the “needs” of your system.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in
Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest the
same week again.)

From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Saritha Vinod
Sent: Tuesday, March 07, 2006 10:42 PM
To: ntfsd redirect
Subject: Re: [ntfsd] Does windows detects UDF formatted hard disk?

Hi Tony,

I will check it with a debugger and get back to you.

Also, does NTFS have a recognizer or is it being directly loaded? Does
that mean that NTFS will be the first one to be given the opportunity to
mount?

Thanks,

Saritha.

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com]On Behalf Of Tony Mason
Sent: Tuesday, March 07, 2006 10:48 PM
To: Windows File Systems Devs Interest List

Subject: RE: FW: [ntfsd] Does windows detects UDF formatted hard
disk?

If the FS Recognizer’s UDFS objects are in use, the UDFS file
system has not been loaded - FS Recognizer is a “stand in” driver that
is used to defer loading of the regular file system until it is needed.
To determine more would require a bit of work with the debugger ( e.g.,
check and see if the recognizer is being called to mount the volume.)
If its not being called, then the next “trick” would be to force the
loading of UDFS (which would then cause registration, which would then
mean it gets called prior to NTFS.) Seriously, this is something that
you should be able to figure out in about 10-15 minutes with a kernel
debugger attached (I’ve had to do this before.) Look at the fs
recognizer’s device object, set a break point in its fs control function
and watch to see if it gets called with the UDFS recognizer object. If
it doesn’t then do the same thing to NTFS and watch its return code -
that’s going to be the key to the whole thing.

I’m not sure how the service control manager handles disabled
drivers anymore. If you can’t start it through the SCM, you’ll need to
call ZwLoadDriver directly to accomplish this.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com http:</http:>

Looking forward to seeing you at the next OSR File Systems class
in Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest
the same week again.)

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com http:</http:>

Looking forward to seeing you at the next OSR File Systems class
in Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest
the same week again.)

From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Saritha Vinod
Sent: Tuesday, March 07, 2006 1:23 AM
To: ntfsd redirect
Subject: Re: FW: [ntfsd] Does windows detects UDF formatted hard
disk?

Hi Tony,

Thanks for the information.

I checked in our Windows 2000 machine also. As you said, the
UDFS file system has two device objects for FILE_DEVICE_DISK_FILE_SYSTEM
and FILE_DEVICE_CD_ROM_FILE_SYSTEM. Hence it would mean that it should
be given the opportunity to mount on disk as well as CD/DVD devices,
right?

As you said, the last registered file system will be called
first. So how can we change the order in which the registration happens?

As far as changing the load order is concerned, what I observed
is that, a file system recognizer is registered with a start type
1(system start) and group “boot file system”. The fs_rec has device
objects like"UdfsDiskRecognizer" and “UdfsCdromRecognizer”. The actual
UDFS file system driver has a start type of 4(disabled), which will be
called by the recognizer. So in this case how can we make the
“UdfsDiskRecognizer” to be called first to recognize the volume?

Also NTFS does not have a recognizer. Hence does it mean that
NTFS is always being called first to mount on a device?

Thanks,

Saritha.

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Tony Mason
Sent: Tuesday, March 07, 2006 1:14 AM
To: Windows File Systems Devs Interest List
Subject: RE: [ntfsd] Does windows detects UDF formatted
hard disk?

Each file system implementation is free to decide how it
recognizes its own file system type. The UDFS file system (at least on
my XP box) has registered for both CD and DISK mount events, so I would
assume it can recognize a UDFS formatted disk drive type. With a tool
like objdir or winobj or the debugger, you should be able to determine
what the UDFS driver has registered as well (the device objects with
names have normally been registered for mount events.)

The media type does matter - Windows only supports mount
on four media types: FILE_DEVICE_DISK, FILE_DEVICE_TAPE,
FILE_DEVICE_CD_ROM, FILE_DEVICE_VIRTUAL_DISK - with the latter being
“lumped into” the same file system type as the first one. File systems
of type FILE_DEVICE_DISK_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_DISK or FILE_DEVICE_VIRTUAL_DISK media. File systems of
type FILE_DEVICE_CD_ROM_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_CD_ROM, etc.

To achieve this, the file system must create a unique
device object and register that device object with the I/O Manager
(IoRegisterFileSystem). The I/O Manager then maintains a LIFO call
table of file systems (last registered, first called) that are invoked
to check a media device and determine if the volume in question has the
right format.

One issue I’ve seen interfere with mounting in the past
is that the I/O Manager is very sensitive to errors returned by the
mounting file system. It expects STATUS_UNRECOGNIZED_VOLUME (see
FatMountVolume in fsctrl.c for FAT). Other errors can (and do) cause
mounting problems. For example, we had an FSD that was written to work
with WORM media. If NTFS were asked to mount the volume first and it
attempted to read an unrecorded area on the media it would get an I/O
error (indicating that the sector had not yet been recorded). NTFS
would report this error to the I/O Manager and the I/O Manager would
abort the mount processing - so our file system never was given an
opportunity to mount. Different media, or different load ordering and
the mount proceeded correctly. This was many years ago and at the time
I lobbied for changes to the I/O Manager to be a bit more liberal in its
decision to continue mount processing but was told that this wouldn’t
happen because it only affected a non-MS file system.

Bottom line: mount processing is an elaborate dance with
multiple players, each of whom must behave in a proscribed manner. A
failure to do so may lead to cases where a volume may not behave the way
that you expect.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com http:</http:>

Looking forward to seeing you at the next OSR File
Systems class in Boston, MA April 18-21, 2006 (note new date - MS
scheduled plugfest the same week again.)

From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Saritha Vinod
Sent: Monday, March 06, 2006 7:16 AM
To: ntfsd redirect
Subject: [ntfsd] Does windows detects UDF formatted hard
disk?

Hi all,

I am trying to format a hard disk partition using UDF
file system. Since windows 2000 does not have write support for UDF, I
formatted using Linux and was able to read and write to it. The UDF
version used was 1.50. I tried accessing that partition again in
Windows. But windows failed to recognize it and showed that it is not
formatted. Can anybody please tell me the reason for this? Is it that
windows will not recognize UDF on hard disk, since it tries to mount UDF
only for CD/DVD devices?

Is the media type in anyway related to this behaviour?

Thanks in advance.

Saritha.

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a
blank email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown
lmsubst tag argument: ‘’
To unsubscribe send a blank email to
xxxxx@lists.osr.com

The information contained in this electronic message and
any attachments to this message are intended for the exclusive use of
the addressee(s)and may contain confidential or privileged information.
If you are not the intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a
blank email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag
argument: ‘’

To unsubscribe send a blank email to
xxxxx@lists.osr.com

The information contained in this electronic message and any
attachments to this message are intended for the exclusive use of the
addressee(s)and may contain confidential or privileged information. If
you are not the intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a
blank email to xxxxx@lists.osr.com

8

Thanks Tony for the clarification.

Regards,

Saritha.

-----Original Message-----
*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com]*On Behalf Of *Tony Mason
*Sent:* Wednesday, March 08, 2006 10:22 AM
*To:* Windows File Systems Devs Interest List
*Subject:* RE: [ntfsd] Does windows detects UDF formatted hard disk?

What file systems are loaded depends upon what file systems are needed.
The point of using the recognizer is that it means you don’t load file
systems until you really need them. But if NTFS is your boot file system
then it will be loaded. If you booted off FAT then IT would be loaded. The
first time that something accesses a CD-ROM (oh, like autoplay in Explorer)
then CDFS or UDFS will load, etc.

So, there is no definitive answer here ? the loading process is dynamic
and based upon the “needs” of your system.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in Boston,
MA April 18-21, 2006 (note new date - MS scheduled plugfest the same week
again.)

*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com] *On Behalf Of *Saritha Vinod
*Sent:* Tuesday, March 07, 2006 10:42 PM
*To:* ntfsd redirect
*Subject:* Re: [ntfsd] Does windows detects UDF formatted hard disk?

Hi Tony,

I will check it with a debugger and get back to you.

Also, does NTFS have a recognizer or is it being directly loaded? Does
that mean that NTFS will be the first one to be given the opportunity to
mount?

Thanks,

Saritha.

-----Original Message-----
*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com]*On Behalf Of *Tony Mason
*Sent:* Tuesday, March 07, 2006 10:48 PM
*To:* Windows File Systems Devs Interest List

*Subject:* RE: FW: [ntfsd] Does windows detects UDF formatted hard disk?

If the FS Recognizer’s UDFS objects are in use, the UDFS file system has
not been loaded ? FS Recognizer is a “stand in” driver that is used to defer
loading of the regular file system until it is needed. To determine more
would require a bit of work with the debugger ( e.g., check and see if the
recognizer is being called to mount the volume.) If its not being called,
then the next “trick” would be to force the loading of UDFS (which would
then cause registration, which would then mean it gets called prior to
NTFS.) Seriously, this is something that you should be able to figure out
in about 10-15 minutes with a kernel debugger attached (I’ve had to do this
before.) Look at the fs recognizer’s device object, set a break point in
its fs control function and watch to see if it gets called with the UDFS
recognizer object. If it doesn’t then do the same thing to NTFS and watch
its return code ? that’s going to be the key to the whole thing.

I’m not sure how the service control manager handles disabled drivers
anymore. If you can’t start it through the SCM, you’ll need to call
ZwLoadDriver directly to accomplish this.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in Boston,
MA April 18-21, 2006 (note new date - MS scheduled plugfest the same week
again.)

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in Boston,
MA April 18-21, 2006 (note new date - MS scheduled plugfest the same week
again.)

*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com] *On Behalf Of *Saritha Vinod
*Sent:* Tuesday, March 07, 2006 1:23 AM
*To:* ntfsd redirect
*Subject:* Re: FW: [ntfsd] Does windows detects UDF formatted hard disk?

Hi Tony,

Thanks for the information.

I checked in our Windows 2000 machine also. As you said, the UDFS file
system has two device objects for FILE_DEVICE_DISK_FILE_SYSTEM and
FILE_DEVICE_CD_ROM_FILE_SYSTEM. Hence it would mean that it should be given
the opportunity to mount on disk as well as CD/DVD devices, right?

As you said, the last registered file system will be called first. So how
can we change the order in which the registration happens?

As far as changing the load order is concerned, what I observed is that, a
file system recognizer is registered with a start type 1(system start) and
group “boot file system”. The fs_rec has device objects
like"UdfsDiskRecognizer" and “UdfsCdromRecognizer”. The actual UDFS file
system driver has a start type of 4(disabled), which will be called by the
recognizer. So in this case how can we make the “UdfsDiskRecognizer” to be
called first to recognize the volume?

Also NTFS does not have a recognizer. Hence does it mean that NTFS is
always being called first to mount on a device?

Thanks,

Saritha.

-----Original Message-----
*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com]* On Behalf Of *Tony Mason
*Sent:* Tuesday, March 07, 2006 1:14 AM
*To:* Windows File Systems Devs Interest List
*Subject:* RE: [ntfsd] Does windows detects UDF formatted hard disk?

Each file system implementation is free to decide how it recognizes its
own file system type. The UDFS file system (at least on my XP box) has
registered for both CD and DISK mount events, so I would assume it can
recognize a UDFS formatted disk drive type. With a tool like objdir or
winobj or the debugger, you should be able to determine what the UDFS driver
has registered as well (the device objects with names have normally been
registered for mount events.)

The media type does matter ? Windows only supports mount on four media
types: FILE_DEVICE_DISK, FILE_DEVICE_TAPE, FILE_DEVICE_CD_ROM,
FILE_DEVICE_VIRTUAL_DISK ? with the latter being “lumped into” the same file
system type as the first one. File systems of type
FILE_DEVICE_DISK_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_DISK or FILE_DEVICE_VIRTUAL_DISK media. File systems of type
FILE_DEVICE_CD_ROM_FILE_SYSTEM are given the opportunity to mount
FILE_DEVICE_CD_ROM, etc.

To achieve this, the file system must create a unique device object and
register that device object with the I/O Manager (IoRegisterFileSystem).
The I/O Manager then maintains a LIFO call table of file systems (last
registered, first called) that are invoked to check a media device and
determine if the volume in question has the right format.

One issue I’ve seen interfere with mounting in the past is that the I/O
Manager is very sensitive to errors returned by the mounting file system.
It expects STATUS_UNRECOGNIZED_VOLUME (see FatMountVolume in fsctrl.c for
FAT). Other errors can (and do) cause mounting problems. For example, we
had an FSD that was written to work with WORM media. If NTFS were asked to
mount the volume first and it attempted to read an unrecorded area on the
media it would get an I/O error (indicating that the sector had not yet been
recorded). NTFS would report this error to the I/O Manager and the I/O
Manager would abort the mount processing ? so our file system never was
given an opportunity to mount. Different media, or different load ordering
and the mount proceeded correctly. This was many years ago and at the time
I lobbied for changes to the I/O Manager to be a bit more liberal in its
decision to continue mount processing but was told that this wouldn’t happen
because it only affected a non-MS file system.

Bottom line: mount processing is an elaborate dance with multiple players,
each of whom must behave in a proscribed manner. A failure to do so may
lead to cases where a volume may not behave the way that you expect.

Regards,

Tony

Tony Mason

Consulting Partner

OSR Open Systems Resources, Inc.

http://www.osr.com

Looking forward to seeing you at the next OSR File Systems class in
Boston, MA April 18-21, 2006 (note new date - MS scheduled plugfest the
same week again.)

*From:* xxxxx@lists.osr.com [mailto:
xxxxx@lists.osr.com] *On Behalf Of *Saritha Vinod
*Sent:* Monday, March 06, 2006 7:16 AM
*To:* ntfsd redirect
*Subject:* [ntfsd] Does windows detects UDF formatted hard disk?

Hi all,

I am trying to format a hard disk partition using UDF file system. Since
windows 2000 does not have write support for UDF, I formatted using Linux
and was able to read and write to it. The UDF version used was 1.50. I
tried accessing that partition again in Windows. But windows failed to
recognize it and showed that it is not formatted. Can anybody please tell me
the reason for this? Is it that windows will not recognize UDF on hard disk,
since it tries to mount UDF only for CD/DVD devices?

Is the media type in anyway related to this behaviour?

Thanks in advance.

Saritha.

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a blank
email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag argument: ‘’

To unsubscribe send a blank email to xxxxx@lists.osr.com

The information contained in this electronic message and any attachments
to this message are intended for the exclusive use of the addressee(s)and
may contain confidential or privileged information. If you are not the
intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a blank
email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag argument: ‘’

To unsubscribe send a blank email to xxxxx@lists.osr.com

The information contained in this electronic message and any attachments
to this message are intended for the exclusive use of the addressee(s)and
may contain confidential or privileged information. If you are not the
intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in

— Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17 You are currently subscribed
to ntfsd as: unknown lmsubst tag argument: ‘’ To unsubscribe send a blank
email to xxxxx@lists.osr.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: unknown lmsubst tag argument: ‘’

To unsubscribe send a blank email to xxxxx@lists.osr.com

The information contained in this electronic message and any attachments
to this message are intended for the exclusive use of the addressee(s)and
may contain confidential or privileged information. If you are not the
intended recipient, please notify the sender or
xxxxx@tataelxsi.co.in