When does IOCTL_VOLUME_ONLINE is sent

Hi,
I am currently investigating the IOCTL_VOLUME_ONLINE. I need to
understand the timing of this IOCTL in regard to I/Os to the volume.
The timing is extermely important for my volume upper filter driver
implementation.
According to the docs, read and write aren't allowed until this IOCTL
completes successfully. However, several checks on a win2k3 box showed
that the first IRP read can be sent even before this IOCTL happens. For
my driver, I don't really care about reads. However, I need a guarantee
that no writes can occur until this IOCTL completes and I cannot find
it. Does anyone here more info about this issue?

Thanks,
Eran.

BTW
Obviously, my filter can compelete any writes that reach before the
IOCTL with an error, however I am afraid doing so will break something.

Maxim
Wed Jan 03 16:25:08 CST 2007

I would not meddle with this feature. Setting the volume offline can easily
cause the "Lost Delayed Write Data" message, especially on $BitMap file.

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

<eran.borovik@gmail.com> wrote in message
news:1167729924.750434.321440@k21g2000cwa.googlegroups.com...
> Hi,
> I am currently investigating the IOCTL_VOLUME_ONLINE. I need to
> understand the timing of this IOCTL in regard to I/Os to the volume.
> The timing is extermely important for my volume upper filter driver
> implementation.
> According to the docs, read and write aren't allowed until this IOCTL
> completes successfully. However, several checks on a win2k3 box showed
> that the first IRP read can be sent even before this IOCTL happens. For
> my driver, I don't really care about reads. However, I need a guarantee
> that no writes can occur until this IOCTL completes and I cannot find
> it. Does anyone here more info about this issue?
>
> Thanks,
> Eran.
>
> BTW
> Obviously, my filter can compelete any writes that reach before the
> IOCTL with an error, however I am afraid doing so will break something.
>

Thomas
Wed Jan 03 21:54:14 CST 2007

Maxim S. Shatskih wrote:
> I would not meddle with this feature. Setting the volume offline can easily
> cause the "Lost Delayed Write Data" message, especially on $BitMap file.

As I understand the question, the OP asks if he can safely complete
write-IRPs with an error in his filter driver before IOCTL_VOLUME_ONLINE
completes successfully.
Not setting offline of a volume.

--
Thomas
http://www.netmeister.org/news/learn2quote.html

eran
Thu Jan 04 03:05:47 CST 2007


Thomas J. Gritzan wrote:
> Maxim S. Shatskih wrote:
> > I would not meddle with this feature. Setting the volume offline can easily
> > cause the "Lost Delayed Write Data" message, especially on $BitMap file.
>
> As I understand the question, the OP asks if he can safely complete
> write-IRPs with an error in his filter driver before IOCTL_VOLUME_ONLINE
> completes successfully.
> Not setting offline of a volume.
>
> --
> Thomas
> http://www.netmeister.org/news/learn2quote.html

You understood me correctly. So, does anyone have an answer for this
one?

Thanks,
Eran.