Device Type 0x53

pratima_kudale · November 1, 2006, 7:22am

Do any one knows that 0x53 stands for which device type?

Thanks,
Pratima

OSR_Community_User · November 1, 2006, 7:31am

From ntifs.h:

#define VOLSNAPCONTROLTYPE ((ULONG) ‘S’)

There are a lot of device types defined in this way, so you may convert hex
number to character and search for it.

Andrey Gunko
soft Xpansion Ukraine Ltd.
Programmer
Powered by eKnow-how
Artjoma St. 118B … 83048 Donetsk … Tel/Fax: +38 062 3818874 …
Internet: [www.soft-xpansion.com]

pratima_kudale · November 1, 2006, 7:59am

Thanks for quick reply.

Actually, I am developing virtual disk drive and getting following 2 Ioctls:

IoCtl code = 0x00530018
Device = 0x53, Function = 0x6, Access = FILE_ANY_ACCESS, Method = METHOD_BUFFERED
IoCtl code = 0x00530050
Device = 0x53, Function = 0x14, Access = FILE_ANY_ACCESS, Method = METHOD_BUFFERED

Right now I don’t have ntifs.h, do you know these IoCtl definitions?

Thanks a lot,
Pratima

OSR_Community_User · November 1, 2006, 8:38am

What OS version do you have?
In ntifs.h (winddk 3790 2003 Server) there only one definition
#define IOCTL_VOLSNAP_FLUSH_AND_HOLD_WRITES
CTL_CODE(VOLSNAPCONTROLTYPE, 0, METHOD_BUFFERED, FILE_READ_ACCESS |
FILE_WRITE_ACCESS)

And this is the only thing I found about it in documentation (may be it
would help you):

" Volume Snapshot Service
A volume snapshot is a point-in-time copy of that volume. The snapshot is
typically used by a backup application so that it may backup files in a
consistent manner, even though the files may be changing during the backup.
Windows XP includes a framework for orchestrating the timing for a snapshot,
as well as a storage filter driver, not a file system filter driver, that
uses a copy-on-write technique in order to create a snapshot.

One important new snapshot-related I/O Control (IOCTL) that affects file
systems is IOCTL_VOLSNAP_FLUSH_AND_HOLD_WRITES. This is actually intended
for interpretation by file systems, even though it is an IOCTL. This is
because all file systems should pass the IOCTL down to a lower-level driver
that is waiting to process the IOCTL after the file system. The choice of an
IOCTL instead of an FSCTL ensures that even legacy file system drivers will
pass the IOCTL down.

This IOCTL is sent by the Volume Snapshot Service. When a file system such
as NTFS receives the IOCTL, it should flush the volume and hold all file
resources to make sure that nothing more gets dirty. When the IRP completes
or is canceled, the file system then releases the resources and returns."

Andrey Gunko
soft Xpansion Ukraine Ltd.
Programmer
Powered by eKnow-how
Artjoma St. 118B … 83048 Donetsk … Tel/Fax: +38 062 3818874 …
Internet: [www.soft-xpansion.com]