[PATCH v3 3/3] nvme_fc: Avoid duplicate associations between same port pairs

[Christoph Hellwig]

On Mon, Sep 18, 2017 at 09:28:35AM -0700, James Smart wrote:
> The desire for FC is to have the same dynamic discovery that it has for
> SCSI. Thus the udev events that kick off scanning. The events are posted
> when connectivity is first detected as well as conditions where the
> discovery server content may have changed (new subsystems added for
> example).  Since those events are ignorant of what's already connected, it
> make no sense to create additional controllers/devices if there's already a
> controller connected.
> 
> The alternative is to drive all connections manually which makes a very
> difficult to manage system for an administrator, especially on "cable-pull"
> scenarios. There is no need for this with FC.

The add a connect options that checks for duplicates instead of making
it the only options.  And please make it a global check for all
fabrics transports.