Christof Schmitt wrote:
James, i try to understand what the introduction of the vports means for zfcp, since this driver also supports NPIV. The documentation for the fc transport class describes a driver that would fully control the adapter and the creation of virtual address. Since you mentioned Xen, i assume that this could be a dom0.
All true. But, there is the notion that there is a driver that thinks it's controlling the adapter, but it's actually talking to a virtual thing, that traps the driver's FLOGI's and turns it into FDISCs...
With zfcp, the hardware FCP adapter does NPIV and only hands out the virtual address to individual Linux instances. zfcp gets the assigned virtual address for the Linux instance. This address is used for allocating the scsi_host structure. Basically, the whole system uses NPIV, but each Linux only uses one assigned virtual WWPN.
Yes - I understand. For all intents and purposes, that virtual address is treated as an adapter.
My current understanding is that the vports introduced in the fc transport class do not affect the Linux systems that only use one virtual address. To map this to Xen, the dom0 would use the vports to show all virtual address, and each domU would use the assigned virtual address without showing the vport in sysfs. Is this correct? Christof
Agreed. It should mean nothing to the zfcp driver. Nothing changes in the driver if it will always be a single address. Although - if your hardware-to-driver interface had the ability to instantiate a new address, you could augment your driver to support the vport calls. That's a choice for you though. -- james PS: One thing I didn't call out in the vport patches was the expectation that the vport-supporting driver had to set the PPN attribute appropriately. And... did you see that T11 is trying to change what the PPN is set to - the fabric port_name not the physical N_Port port_name. - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
