Additional subcommands for xm:

xm npiv-add <domid> [-p <virtual port WWN>] [-n <virtual node WWN>] \
		<physical port WWN[, physical port WWN...]>

Add a config entry of the virtual port WWN and associated virtual node WWN
to the domain specified by domid, along with candidate physical ports where the 
virtual port could be created on. If virtual port/node WWN are not specified, 
they will be generated.

xm npiv-mod <domid> -p <virtual port WWN> -n <virtal node WWN> \
	<physical port WWN[, physical port WWN...]>

Modify the config entry of the virtual node WWN and the physical port WWN list
with the specified virtual port WWN.

xm npiv-rm <domid> -p <virtual port WWN>

Remove the config entry of the virtual port WWN from the domain 
specified by domid.

xm npiv-enable <domid> -p <virtual port WWN>

Create the specified virtual port on the first available physical port, the
virtual port WWN will be marked as 'enabled' after that no matter if the
creation fails or not.

xm npiv-disable <domid> -p <virtual port WWN>

Delete the specified virtual port and associated storage devices from
the domain. The virtual port WWN will be marked as 'disabled' after that if
matter if the deletion fails or not.

xm npiv-list <domid>

List all the virtual port WWN set on the domain along with:
	virtual node WWN
	WWN list of candidate physical ports
	storage over the virtual port, if any