Hi all -
New to this forum so please forgive the newbee questions.. :-))
Looking for information on direct access/control for storage devices (ide, scsi, CD-Rom and DVD).

Is there a way to gain access for reads/write w/o having ring 0 access? Where can I find good info on this topic?

thanks in advace for replys.
regards
Dave
Posted on 2002-04-22 23:31:12 by dlburlin
Me also ... for my new operating system ;)

On windows NT/2k/XP no way (yet). You should do at least a Kernel Mode Driver or a WDM to support Plug and Play...

On Win9x a VxD (see Iczelion's great VxD tutorials) will get you legitimate Ring0 acces. Here i have seen direct writes to port to be kind of working but its hackish and unrecomended as it will bring havoc to other drivers and to the system...but it can be done.

There is a WinIO library on systeminternals site for doing such things without writing the drivers and another one using Callgates if i remember corectly *do a search on Gogle on above terms, but i guess they are commercial ...

check this links
http://www.geocities.com/SiliconValley/Peaks/8600/device.html
http://www.stanford.edu/~csapuntz/blackmagic.html
http://www.beyondlogic.org/
http://www.nondot.org/sabre/os/articles
Posted on 2002-04-23 00:12:05 by BogdanOntanu
Unless you're writing a driver (and here I mean an actual driver for
a device, not just driver as in "way to gain ring0"), the only "direct
access" you should do to storage devices would be via CreateFile
on NT systems, with the "\\.\PHYSICALDRIVEx" or "\\.\?:" special
filenames. There's just too much that can go wrong, and too little
reason to do it.

Oh yeah, there's also the ASPI stuff if you want to do CD ripping.
Posted on 2002-04-23 09:38:55 by f0dder
BogdanOntanu,
Thanks for you input AND links. I think they've provided me exactly what Im looking for.
Regards
Dave
:alright:

f0dder
Thank you as well. I do understand what your saying, and am painfully aware of the havoc that can be caused by indiscriminate direct I/O access. However, I'll need complete control of cd/dvd drives if I am to accomplish my goal. Thanks for you words of caution.
regards
Dave
:)
Posted on 2002-04-23 22:36:05 by dlburlin