FltReadFile in Post Directory Control

NTFSD
1

Hi,

I have a requirement to read file in post directory control. But documentation say FltReadFile must be running at IRQL PASSIVE_LEVEL. So it is not advisable to use this call in post. Please suggest me alternative way of doing the same.

Regards

Aishwary Bhashkar
R Systems International Ltd.

2

Read the file from a workitem queued from your PostDirCtrl.

wrote in message news:xxxxx@ntfsd…
> Hi,
>
> I have a requirement to read file in post directory control. But
documentation say FltReadFile must be running at IRQL PASSIVE_LEVEL. So it
is not advisable to use this call in post. Please suggest me alternative
way of doing the same.
>
> Regards
>
> Aishwary Bhashkar
> R Systems International Ltd.
>
>

3

Thanks I guess this should Work.

Regards

Aishwary Bhashkar
R Systems International Ltd.

4

Hi,

I have the problem with effciency of the this code. It returns after a long time even making it CriticalWorkQueue

Regards

Aishwary Bhashkar
R Systems International Ltd.

5

even if you call FltDoCompletionProcessingWhenSafe from
post-IRP_MJ_DIRECTORY_CONTROL callback? Sometimes I use it in
post-IRP_MJ_WRITE operation and it doesnt seem to be slow – but internally,
FltDoCompletionProcessingWhenSafe uses work items… why do you call
FltReadFile? is it really needed?

-pk

wrote in message news:xxxxx@ntfsd…
> Hi,
>
> I have the problem with effciency of the this code. It returns after a
> long time even making it CriticalWorkQueue
>
> Regards
>
> Aishwary Bhashkar
> R Systems International Ltd.
>

6

Ok I will try it doing this way. Well Actualy I have to put this to make my filter compatible with CA anti-virus. It seems that they are doing some I/O operations on service and we are also doing the same. Now it happens that when we make I/O operations from service having antivirus installed. It gets into deadlock. So we are putting I/O operations on filter so that to avoid deadlock.

Thanks & Regards

Aishwary Bhashkar
R Systems International Ltd.

7

There is one more problem I am getting in postdirctrl, I am getting IoGetTopLevelIrp() is not NULL, though FileSpy shows its NULL. So how to use workitem queued in this case.

Thanks & Regards

Aishwary Bhashkar
R systems International Ltd.