[Simh] Disk sizing

[Mark Pizzolato]

On Monday, February 6, 2017 at 4:55 PM, Mark Pizzolato wrote:
> On Monday, February 6, 2017 at 12:39 PM, Johnny Billquist wrote:
> > On 2017-02-06 19:38, Mark Pizzolato wrote:
> > > Rather than that, please just give the latest github code a spin to
> > > see if the
> > > ODS1 volumes you have at your fingertips are correctly recognized
> > > when they are attached to a RP or RQ device.
> >
> > What can I expect to see? I mean, my images are already the correct
> > size anyway, so the sizing should not result in any difference than today...
> > I'll try it when I get a little time. Maybe this weekend. I guess it's
> > time I updated my version of simh anyway. :-)
> 
> While processing the ATTACH command, if it detects a particular file system it
> announces what it has found and if auto sizing is enabled and the disk size is
> smaller than the file system size, then the disk size is expanded to allow
> access to the full useful extent of the disk container by the simulated system.
> If auto sizing is disabled, then a message explaining that data access errors
> are likely with the current size of the disk.
> 
> > > Bringing this functionality to other disk types is a project for
> > > another day and might not provide much value since most, if not all,
> > > of them had their last track written with BAD144 data.
> >
> > Well, in the case of ODS, the code should work fine on any kind of
> > disk, so there is really no reason to limit it to some controllers.
> 
> It is not a about a specifically limiting the functionality.  The code is built into
> the sim_disk functionality which currently is only used by the RQ and RP
> devices.
> 
> The project for another day is to either make the existing file system checking
> flexible enough to work for both the sim_disk using code and the legacy
> sim_fio code, OR to convert the RL and HK devices to use sim_disk.

Another day has come and the RL and HK devices now have the file system 
validation support for auto sizing also.

- Mark