Re[4]: driver load order

Hello Alex,

no, looooong after that :). i was pointing out that it is possible to
open a device even if it is not mounted (i.e. it has no media … of
course, there is also the posibility that my understanding of the word
mounted is wrong ; does it imply the presence of media in the drive ?).


Best regards,
Alex mailto:xxxxx@bitdefender.com

Friday, June 24, 2005, 12:19:32 PM, you wrote:

> I have been able to open symbolic links to volumes that had no
> media ( floppy, cd-rom ), using “\\.a:”. ( any letter, of
> course) The device would open, but it would of course fail
> some operations.
The most interesting part of the question is “when”?
In DriverEntry of a BOOT_START (filter) driver?
(my guess the answer is “no”).

Regards,
Alex

----- Original Message -----
From: “Alex Carp”
> To: “Windows File Systems Devs Interest List”
> Sent: Friday, June 24, 2005 5:06 AM
> Subject: Re[2]: [ntfsd] driver load order

>> Hello Ladislav,
>>
>> I have been able to open symbolic links to volumes that had no
>> media ( floppy, cd-rom ), using "\\.
>>
>>
>> –
>> Best regards,
>> Alex mailto:xxxxx@bitdefender.com
>>
>> Friday, June 24, 2005, 11:48:10 AM, you wrote:
>>
>>>> When this is done it causes the volume you are accessing (probably the
>>>> boot volume) to mount prematurely. When this occurs the volume is not
>>>> setup with the proper state.
>>
>>> Let me ask one more question - Could I try to open the symbolic link
>>> first to make sure that the volume is mounted and then, If I am able to
>>> open the link, can I expect that the volume has been already properly
>>> mounted ?
>>
>>> L.
>>
>>
>>> —
>>> Questions? First check the IFS FAQ at
>>> https://www.osronline.com/article.cfm?id=17
>>
>>> You are currently subscribed to ntfsd as: xxxxx@bitdefender.com
>>> To unsubscribe send a blank email to
>>> xxxxx@lists.osr.com
>>
>>
>>
>>
>>
>> –
>> This message was scanned for spam and viruses by BitDefender.
>> For more information please visit http://www.bitdefender.com/
>>
>>
>> —
>> Questions? First check the IFS FAQ at
>> https://www.osronline.com/article.cfm?id=17
>>
>> You are currently subscribed to ntfsd as: xxxxx@bellsouth.net
>> 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: xxxxx@bitdefender.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com


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> no, looooong after that :).
That was the original question “can I open c:\mysettings.txt at boot?”,
that’s why I asked for a clarification.
If it were possible, it would have been possible to open the file BEFORE the
boot
[and with power off] also:-)

Regards,
Alex

----- Original Message -----
From: “Alex Carp”
To: “Windows File Systems Devs Interest List”
Sent: Friday, June 24, 2005 5:35 AM
Subject: Re[4]: [ntfsd] driver load order

> Hello Alex,
>
> no, looooong after that :). i was pointing out that it is possible to
> open a device even if it is not mounted (i.e. it has no media … of
> course, there is also the posibility that my understanding of the word
> mounted is wrong ; does it imply the presence of media in the drive ?).
>
>
> –
> Best regards,
> Alex mailto:xxxxx@bitdefender.com
>
> Friday, June 24, 2005, 12:19:32 PM, you wrote:
>
>>> I have been able to open symbolic links to volumes that had no
>>> media ( floppy, cd-rom ), using “\\.a:”. ( any letter, of
>>> course) The device would open, but it would of course fail
>>> some operations.
>> The most interesting part of the question is “when”?
>> In DriverEntry of a BOOT_START (filter) driver?
>> (my guess the answer is “no”).
>
>> Regards,
>> Alex
>
>
>> ----- Original Message -----
>> From: “Alex Carp”
>> To: “Windows File Systems Devs Interest List”
>> Sent: Friday, June 24, 2005 5:06 AM
>> Subject: Re[2]: [ntfsd] driver load order
>
>
>>> Hello Ladislav,
>>>
>>> I have been able to open symbolic links to volumes that had no
>>> media ( floppy, cd-rom ), using "\\.
>>>
>>>
>>> –
>>> Best regards,
>>> Alex mailto:xxxxx@bitdefender.com
>>>
>>> Friday, June 24, 2005, 11:48:10 AM, you wrote:
>>>
>>>>> When this is done it causes the volume you are accessing (probably the
>>>>> boot volume) to mount prematurely. When this occurs the volume is not
>>>>> setup with the proper state.
>>>
>>>> Let me ask one more question - Could I try to open the symbolic link
>>>> first to make sure that the volume is mounted and then, If I am able to
>>>> open the link, can I expect that the volume has been already properly
>>>> mounted ?
>>>
>>>> L.
>>>
>>>
>>>> —
>>>> Questions? First check the IFS FAQ at
>>>> https://www.osronline.com/article.cfm?id=17
>>>
>>>> You are currently subscribed to ntfsd as: xxxxx@bitdefender.com
>>>> To unsubscribe send a blank email to
>>>> xxxxx@lists.osr.com
>>>
>>>
>>>
>>>
>>>
>>> –
>>> This message was scanned for spam and viruses by BitDefender.
>>> For more information please visit http://www.bitdefender.com/
>>>
>>>
>>> —
>>> Questions? First check the IFS FAQ at
>>> https://www.osronline.com/article.cfm?id=17
>>>
>>> You are currently subscribed to ntfsd as: xxxxx@bellsouth.net
>>> 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: xxxxx@bitdefender.com
>> To unsubscribe send a blank email to xxxxx@lists.osr.com
>
>
>
>
>
> –
> This message was scanned for spam and viruses by BitDefender.
> For more information please visit http://www.bitdefender.com/
>
>
> —
> Questions? First check the IFS FAQ at
> https://www.osronline.com/article.cfm?id=17
>
> You are currently subscribed to ntfsd as: xxxxx@bellsouth.net
> To unsubscribe send a blank email to xxxxx@lists.osr.com
>

Thank you for the answer

Roman,

You should never open a file from the driver entry routine of any boot
loaded driver in any of the “filter” groups. Doing this causes strange
problems which are very hard to track down.

When this is done it causes the volume you are accessing (probably the
boot volume) to mount prematurely. When this occurs the volume is not
setup with the proper state.

I have debugged these types of issues in the past and they are hard to
track down.

Neal Christiansen
Microsoft File System Filter Group Lead
This posting is provided “AS IS” with no warranties, and confers no
Rights

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Roman Kudinov
Sent: Tuesday, June 21, 2005 10:32 AM
To: Windows File Systems Devs Interest List
Subject: [ntfsd] driver load order

Hi,

Does anybody know if it’s possible to access files from within a
DriverEntry
routine of a storage filter driver which boot order is
SERVICE_BOOT_START? I
need to access at least the system volume

Also IFS Kit says (in “What Happens to File Systems During System Boot”
article):
“Then all drivers in the “filter” load order group are loaded. Note that
the
“filter” group includes storage filter drivers as well as file system
filter
drivers, and it includes third-party as well as built-in filter
drivers.”

Does it mean that filesystem filter drivers may be loaded in the first
order
and storage filter drivers after?

Thank you,
Roman


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

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

Open of the device with DesiredAccess == FILE_READ_ATTRIBUTES will not
trigger the mount.

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

----- Original Message -----
From: “Alex Carp”
To: “Windows File Systems Devs Interest List”
Sent: Friday, June 24, 2005 1:35 PM
Subject: Re[4]: [ntfsd] driver load order

> Hello Alex,
>
> no, looooong after that :). i was pointing out that it is possible to
> open a device even if it is not mounted (i.e. it has no media … of
> course, there is also the posibility that my understanding of the word
> mounted is wrong ; does it imply the presence of media in the drive ?).
>
>
> –
> Best regards,
> Alex mailto:xxxxx@bitdefender.com
>
> Friday, June 24, 2005, 12:19:32 PM, you wrote:
>
> >> I have been able to open symbolic links to volumes that had no
> >> media ( floppy, cd-rom ), using “\\.a:”. ( any letter, of
> >> course) The device would open, but it would of course fail
> >> some operations.
> > The most interesting part of the question is “when”?
> > In DriverEntry of a BOOT_START (filter) driver?
> > (my guess the answer is “no”).
>
> > Regards,
> > Alex
>
>
> > ----- Original Message -----
> > From: “Alex Carp”
> > To: “Windows File Systems Devs Interest List”
> > Sent: Friday, June 24, 2005 5:06 AM
> > Subject: Re[2]: [ntfsd] driver load order
>
>
> >> Hello Ladislav,
> >>
> >> I have been able to open symbolic links to volumes that had no
> >> media ( floppy, cd-rom ), using "\\.
> >>
> >>
> >> –
> >> Best regards,
> >> Alex mailto:xxxxx@bitdefender.com
> >>
> >> Friday, June 24, 2005, 11:48:10 AM, you wrote:
> >>
> >>>> When this is done it causes the volume you are accessing (probably the
> >>>> boot volume) to mount prematurely. When this occurs the volume is not
> >>>> setup with the proper state.
> >>
> >>> Let me ask one more question - Could I try to open the symbolic link
> >>> first to make sure that the volume is mounted and then, If I am able to
> >>> open the link, can I expect that the volume has been already properly
> >>> mounted ?
> >>
> >>> L.
> >>
> >>
> >>> —
> >>> Questions? First check the IFS FAQ at
> >>> https://www.osronline.com/article.cfm?id=17
> >>
> >>> You are currently subscribed to ntfsd as: xxxxx@bitdefender.com
> >>> To unsubscribe send a blank email to
> >>> xxxxx@lists.osr.com
> >>
> >>
> >>
> >>
> >>
> >> –
> >> This message was scanned for spam and viruses by BitDefender.
> >> For more information please visit http://www.bitdefender.com/
> >>
> >>
> >> —
> >> Questions? First check the IFS FAQ at
> >> https://www.osronline.com/article.cfm?id=17
> >>
> >> You are currently subscribed to ntfsd as: xxxxx@bellsouth.net
> >> 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: xxxxx@bitdefender.com
> > To unsubscribe send a blank email to xxxxx@lists.osr.com
>
>
>
>
>
> –
> This message was scanned for spam and viruses by BitDefender.
> For more information please visit http://www.bitdefender.com/
>
>
> —
> Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17
>
> You are currently subscribed to ntfsd as: xxxxx@storagecraft.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com

Hello Neal,

What about AddDevice routine? Can I open a file from it?

Thank you,
Roman Kudinov

“Neal Christiansen” ???/??? ?
??? ???: news:xxxxx@ntfsd…
Roman,

You should never open a file from the driver entry routine of any boot
loaded driver in any of the “filter” groups. Doing this causes strange
problems which are very hard to track down.

When this is done it causes the volume you are accessing (probably the
boot volume) to mount prematurely. When this occurs the volume is not
setup with the proper state.

I have debugged these types of issues in the past and they are hard to
track down.

Neal Christiansen
Microsoft File System Filter Group Lead
This posting is provided “AS IS” with no warranties, and confers no
Rights

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Roman Kudinov
Sent: Tuesday, June 21, 2005 10:32 AM
To: Windows File Systems Devs Interest List
Subject: [ntfsd] driver load order

Hi,

Does anybody know if it’s possible to access files from within a
DriverEntry
routine of a storage filter driver which boot order is
SERVICE_BOOT_START? I
need to access at least the system volume

Also IFS Kit says (in “What Happens to File Systems During System Boot”
article):
“Then all drivers in the “filter” load order group are loaded. Note that
the
“filter” group includes storage filter drivers as well as file system
filter
drivers, and it includes third-party as well as built-in filter
drivers.”

Does it mean that filesystem filter drivers may be loaded in the first
order
and storage filter drivers after?

Thank you,
Roman


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

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

> What about AddDevice routine? Can I open a file from it?

Well, it depends on WHEN the routine is called. If it is too early,
you can meet the same conditions like Neal described in his mail.
The question is not “Can I open a file in this or that routine”,
but “can I open a file at boot time”.

L.

No. This would be a PNP call which means the volume probably hasn’t
been mounted yet.

You shouldn’t open a file on a volume until the volume is mounted. If
you have written a proper file system filter you will know when the
volume mounts and then you can do your open anytime after that.

Remember that you can not open a file while processing a mount request.
The IOManager will hold off create operations until the mount completes
and it does not know it has completed until it sees the mount operation
return.

You should do your own open on the first open you see after mount.

Neal Christiansen
Microsoft File System Filter Group Lead
This posting is provided “AS IS” with no warranties, and confers no
Rights

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Roman Kudinov
Sent: Monday, June 27, 2005 12:58 AM
To: Windows File Systems Devs Interest List
Subject: Re:[ntfsd] driver load order

Hello Neal,

What about AddDevice routine? Can I open a file from it?

Thank you,
Roman Kudinov

“Neal Christiansen” ???/??? ?
??? ???: news:xxxxx@ntfsd…
Roman,

You should never open a file from the driver entry routine of any boot
loaded driver in any of the “filter” groups. Doing this causes strange
problems which are very hard to track down.

When this is done it causes the volume you are accessing (probably the
boot volume) to mount prematurely. When this occurs the volume is not
setup with the proper state.

I have debugged these types of issues in the past and they are hard to
track down.

Neal Christiansen
Microsoft File System Filter Group Lead
This posting is provided “AS IS” with no warranties, and confers no
Rights

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Roman Kudinov
Sent: Tuesday, June 21, 2005 10:32 AM
To: Windows File Systems Devs Interest List
Subject: [ntfsd] driver load order

Hi,

Does anybody know if it’s possible to access files from within a
DriverEntry
routine of a storage filter driver which boot order is
SERVICE_BOOT_START? I
need to access at least the system volume

Also IFS Kit says (in “What Happens to File Systems During System Boot”
article):
“Then all drivers in the “filter” load order group are loaded. Note that
the
“filter” group includes storage filter drivers as well as file system
filter
drivers, and it includes third-party as well as built-in filter
drivers.”

Does it mean that filesystem filter drivers may be loaded in the first
order
and storage filter drivers after?

Thank you,
Roman


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

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