Re: struct class question

[James Bottomley <James.Bottomley@SteelEye.com>]

On Wed, 2005-06-29 at 19:03 -0400, Luben Tuikov wrote:
> > exist at all if we can't do anything with it, I suppose that depends on
> > whether it's necessary to the tree representation or not (a bit like
> > channels in SCSI.  They have meaning, but no sysfs representation on
> > their own).
> 
> Very good analogy.  In this respect I think we should represent
> phys, ports, and expanders just as the discover process sees them,
> in the same way, as you pointed out, channels are represented
> even though the do not quite exist (but are an abstraction).

Right, the question really is can we do anything with it, so targets
have properties (as do devices) but currently we have no channel
properties.

All SCSI devices have "ports" as defined by SAM; however, we don't show
them (well, except FC rports) because we don't use them for anything.

As far at least as SAS expanders go, I believe they do have properties
(the routing table etc.) which the driver can query, so they might be
worth adding a device for.

> Is this
> 
> /sys/class/scsi_host/host1
> 
> Or is it (e.g.),
> 
> /sys/devices/pci0000:00/0000:00:1f.2/host1

The latter (that's the devices tree under /sys/devices).

James