This sounds a lot like the kind of processing that hotplug should do?
David
Alan Altmark
<[EMAIL PROTECTED] To: [EMAIL PROTECTED]
s.ibm.com> cc:
Sent by: Linux Subject: Re: Linux390 + VM + Tape 3490
on 390 Port
<[EMAIL PROTECTED]
ARIST.EDU>
13/06/2003
14:38
Please respond
to Linux on 390
Port
On Thursday, 06/12/2003 at 05:50 MST, Jim Sibley/San Jose/[EMAIL PROTECTED] wrote:
> I think we might be confusing several issues
I think everyone has a good understanding of the issues, Jim. A
requirment to unload/reload the device driver is a non-starter and voids
all of the dynamic device support. To add a tape you must take all other
tapes out of service. That isn't a good strategy. Do you agree with
that?
The point with shared tapes, whether it is a logical or physical sharing,
is that there is *something* under program and/or user control to say
"This is mine until I say it is not". That function is the thing that
must issue the assign/unassign. (I beg everyone not to call it "attach"
or "detach"... those words imply a change in the host device
configuration...assign/unassign do not change the configuration.)
I think that Mr. Boyes is on the right track. This is a function that any
platform that wants to maintain a static device configuration, but allow a
device to go into "away" state will want. There is no need for a special
mainframe-specific paradigm that is somehow imbedded in the driver. As
David said, define a new "reserve/release" ioctl() that will do this and
let the apps (e.g. mt) deal with it.
Alan Altmark
Sr. Software Engineer
IBM z/VM Development
